// arm.cc -- arm target support for gold.
-// Copyright 2009 Free Software Foundation, Inc.
+// Copyright 2009, 2010 Free Software Foundation, Inc.
// Written by Doug Kwan <dougkwan@google.com> based on the i386 code
// by Ian Lance Taylor <iant@google.com>.
// This file also contains borrowed and adapted code from
#include <limits>
#include <cstdio>
#include <string>
+#include <algorithm>
+#include <map>
+#include <utility>
+#include <set>
#include "elfcpp.h"
#include "parameters.h"
#include "tls.h"
#include "defstd.h"
#include "gc.h"
+#include "attributes.h"
+#include "arm-reloc-property.h"
namespace
{
template<bool big_endian>
class Output_data_plt_arm;
+template<bool big_endian>
+class Stub_table;
+
+template<bool big_endian>
+class Arm_input_section;
+
+class Arm_exidx_cantunwind;
+
+class Arm_exidx_merged_section;
+
+class Arm_exidx_fixup;
+
+template<bool big_endian>
+class Arm_output_section;
+
+class Arm_exidx_input_section;
+
+template<bool big_endian>
+class Arm_relobj;
+
+template<bool big_endian>
+class Arm_relocate_functions;
+
+template<bool big_endian>
+class Arm_output_data_got;
+
template<bool big_endian>
class Target_arm;
const int32_t THM2_MAX_FWD_BRANCH_OFFSET = (((1 << 24) - 2) + 4);
const int32_t THM2_MAX_BWD_BRANCH_OFFSET = (-(1 << 24) + 4);
+// Thread Control Block size.
+const size_t ARM_TCB_SIZE = 8;
+
// The arm target class.
//
// This is a very simple port of gold for ARM-EABI. It is intended for
-// supporting Android only for the time being. Only these relocation types
-// are supported.
-//
-// R_ARM_NONE
-// R_ARM_ABS32
-// R_ARM_ABS32_NOI
-// R_ARM_ABS16
-// R_ARM_ABS12
-// R_ARM_ABS8
-// R_ARM_THM_ABS5
-// R_ARM_BASE_ABS
-// R_ARM_REL32
-// R_ARM_THM_CALL
-// R_ARM_COPY
-// R_ARM_GLOB_DAT
-// R_ARM_BASE_PREL
-// R_ARM_JUMP_SLOT
-// R_ARM_RELATIVE
-// R_ARM_GOTOFF32
-// R_ARM_GOT_BREL
-// R_ARM_GOT_PREL
-// R_ARM_PLT32
-// R_ARM_CALL
-// R_ARM_JUMP24
-// R_ARM_TARGET1
-// R_ARM_PREL31
-// R_ARM_ABS8
-// R_ARM_MOVW_ABS_NC
-// R_ARM_MOVT_ABS
-// R_ARM_THM_MOVW_ABS_NC
-// R_ARM_THM_MOVT_ABS
-// R_ARM_MOVW_PREL_NC
-// R_ARM_MOVT_PREL
-// R_ARM_THM_MOVW_PREL_NC
-// R_ARM_THM_MOVT_PREL
+// supporting Android only for the time being.
//
// TODOs:
-// - Generate various branch stubs.
-// - Support interworking.
-// - Define section symbols __exidx_start and __exidx_stop.
-// - Support more relocation types as needed.
+// - Implement all static relocation types documented in arm-reloc.def.
// - Make PLTs more flexible for different architecture features like
// Thumb-2 and BE8.
// There are probably a lot more.
+// Ideally we would like to avoid using global variables but this is used
+// very in many places and sometimes in loops. If we use a function
+// returning a static instance of Arm_reloc_property_table, it will very
+// slow in an threaded environment since the static instance needs to be
+// locked. The pointer is below initialized in the
+// Target::do_select_as_default_target() hook so that we do not spend time
+// building the table if we are not linking ARM objects.
+//
+// An alternative is to to process the information in arm-reloc.def in
+// compilation time and generate a representation of it in PODs only. That
+// way we can avoid initialization when the linker starts.
+
+Arm_reloc_property_table *arm_reloc_property_table = NULL;
+
// Instruction template class. This class is similar to the insn_sequence
// struct in bfd/elf32-arm.c.
enum Type
{
THUMB16_TYPE = 1,
+ // THUMB16_SPECIAL_TYPE is used by sub-classes of Stub for instruction
+ // templates with class-specific semantics. Currently this is used
+ // only by the Cortex_a8_stub class for handling condition codes in
+ // conditional branches.
+ THUMB16_SPECIAL_TYPE,
THUMB32_TYPE,
ARM_TYPE,
DATA_TYPE
};
- // Factory methods to create instrunction templates in different formats.
+ // Factory methods to create instruction templates in different formats.
static const Insn_template
thumb16_insn(uint32_t data)
{ return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 0); }
- // A bit of a hack. A Thumb conditional branch, in which the proper
- // condition is inserted when we build the stub.
+ // A Thumb conditional branch, in which the proper condition is inserted
+ // when we build the stub.
static const Insn_template
thumb16_bcond_insn(uint32_t data)
- { return Insn_template(data, THUMB16_TYPE, elfcpp::R_ARM_NONE, 1); }
+ { return Insn_template(data, THUMB16_SPECIAL_TYPE, elfcpp::R_ARM_NONE, 1); }
static const Insn_template
thumb32_insn(uint32_t data)
reloc_addend() const
{ return this->reloc_addend_; }
- // Return size of instrunction template in bytes.
+ // Return size of instruction template in bytes.
size_t
size() const;
- // Return byte-alignment of instrunction template.
+ // Return byte-alignment of instruction template.
unsigned
alignment() const;
DEF_STUB(a8_veneer_b_cond) \
DEF_STUB(a8_veneer_b) \
DEF_STUB(a8_veneer_bl) \
- DEF_STUB(a8_veneer_blx)
+ DEF_STUB(a8_veneer_blx) \
+ DEF_STUB(v4_veneer_bx)
// Stub types.
arm_stub_cortex_a8_last = arm_stub_a8_veneer_blx,
// Last stub type.
- arm_stub_type_last = arm_stub_a8_veneer_blx
+ arm_stub_type_last = arm_stub_v4_veneer_bx
} Stub_type;
#undef DEF_STUB
write(unsigned char* view, section_size_type view_size, bool big_endian)
{ this->do_write(view, view_size, big_endian); }
+ // Return the instruction for THUMB16_SPECIAL_TYPE instruction template
+ // for the i-th instruction.
+ uint16_t
+ thumb16_special(size_t i)
+ { return this->do_thumb16_special(i); }
+
protected:
// This must be defined in the child class.
virtual Arm_address
do_reloc_target(size_t) = 0;
- // This must be defined in the child class.
+ // This may be overridden in the child class.
virtual void
- do_write(unsigned char*, section_size_type, bool) = 0;
+ do_write(unsigned char* view, section_size_type view_size, bool big_endian)
+ {
+ if (big_endian)
+ this->do_fixed_endian_write<true>(view, view_size);
+ else
+ this->do_fixed_endian_write<false>(view, view_size);
+ }
+ // This must be overridden if a child class uses the THUMB16_SPECIAL_TYPE
+ // instruction template.
+ virtual uint16_t
+ do_thumb16_special(size_t)
+ { gold_unreachable(); }
+
private:
+ // A template to implement do_write.
+ template<bool big_endian>
+ void inline
+ do_fixed_endian_write(unsigned char*, section_size_type);
+
// Its template.
const Stub_template* stub_template_;
// Offset within the section of containing this stub.
unsigned int r_sym_;
// If r_sym_ is invalid index. This points to a global symbol.
// Otherwise, this points a relobj. We used the unsized and target
- // independent Symbol and Relobj classes instead of Arm_symbol and
+ // independent Symbol and Relobj classes instead of Sized_symbol<32> and
// Arm_relobj. This is done to avoid making the stub class a template
- // as most of the stub machinery is endianity-neutral. However, it
+ // as most of the stub machinery is endianness-neutral. However, it
// may require a bit of casting done by users of this class.
union
{
friend class Stub_factory;
- private:
// Return the relocation target address of the i-th relocation in the
// stub.
Arm_address
return this->destination_address_;
}
- // A template to implement do_write below.
- template<bool big_endian>
- void inline
- do_fixed_endian_write(unsigned char*, section_size_type);
+ private:
+ // Address of destination.
+ Arm_address destination_address_;
+};
- // Write a stub.
- void
- do_write(unsigned char* view, section_size_type view_size, bool big_endian);
+// Cortex-A8 stub class. We need a Cortex-A8 stub to redirect any 32-bit
+// THUMB branch that meets the following conditions:
+//
+// 1. The branch straddles across a page boundary. i.e. lower 12-bit of
+// branch address is 0xffe.
+// 2. The branch target address is in the same page as the first word of the
+// branch.
+// 3. The branch follows a 32-bit instruction which is not a branch.
+//
+// To do the fix up, we need to store the address of the branch instruction
+// and its target at least. We also need to store the original branch
+// instruction bits for the condition code in a conditional branch. The
+// condition code is used in a special instruction template. We also want
+// to identify input sections needing Cortex-A8 workaround quickly. We store
+// extra information about object and section index of the code section
+// containing a branch being fixed up. The information is used to mark
+// the code section when we finalize the Cortex-A8 stubs.
+//
- // Address of destination.
+class Cortex_a8_stub : public Stub
+{
+ public:
+ ~Cortex_a8_stub()
+ { }
+
+ // Return the object of the code section containing the branch being fixed
+ // up.
+ Relobj*
+ relobj() const
+ { return this->relobj_; }
+
+ // Return the section index of the code section containing the branch being
+ // fixed up.
+ unsigned int
+ shndx() const
+ { return this->shndx_; }
+
+ // Return the source address of stub. This is the address of the original
+ // branch instruction. LSB is 1 always set to indicate that it is a THUMB
+ // instruction.
+ Arm_address
+ source_address() const
+ { return this->source_address_; }
+
+ // Return the destination address of the stub. This is the branch taken
+ // address of the original branch instruction. LSB is 1 if it is a THUMB
+ // instruction address.
+ Arm_address
+ destination_address() const
+ { return this->destination_address_; }
+
+ // Return the instruction being fixed up.
+ uint32_t
+ original_insn() const
+ { return this->original_insn_; }
+
+ protected:
+ // Cortex_a8_stubs are created via a stub factory. So these are protected.
+ Cortex_a8_stub(const Stub_template* stub_template, Relobj* relobj,
+ unsigned int shndx, Arm_address source_address,
+ Arm_address destination_address, uint32_t original_insn)
+ : Stub(stub_template), relobj_(relobj), shndx_(shndx),
+ source_address_(source_address | 1U),
+ destination_address_(destination_address),
+ original_insn_(original_insn)
+ { }
+
+ friend class Stub_factory;
+
+ // Return the relocation target address of the i-th relocation in the
+ // stub.
+ Arm_address
+ do_reloc_target(size_t i)
+ {
+ if (this->stub_template()->type() == arm_stub_a8_veneer_b_cond)
+ {
+ // The conditional branch veneer has two relocations.
+ gold_assert(i < 2);
+ return i == 0 ? this->source_address_ + 4 : this->destination_address_;
+ }
+ else
+ {
+ // All other Cortex-A8 stubs have only one relocation.
+ gold_assert(i == 0);
+ return this->destination_address_;
+ }
+ }
+
+ // Return an instruction for the THUMB16_SPECIAL_TYPE instruction template.
+ uint16_t
+ do_thumb16_special(size_t);
+
+ private:
+ // Object of the code section containing the branch being fixed up.
+ Relobj* relobj_;
+ // Section index of the code section containing the branch begin fixed up.
+ unsigned int shndx_;
+ // Source address of original branch.
+ Arm_address source_address_;
+ // Destination address of the original branch.
Arm_address destination_address_;
+ // Original branch instruction. This is needed for copying the condition
+ // code from a condition branch to its stub.
+ uint32_t original_insn_;
+};
+
+// ARMv4 BX Rx branch relocation stub class.
+class Arm_v4bx_stub : public Stub
+{
+ public:
+ ~Arm_v4bx_stub()
+ { }
+
+ // Return the associated register.
+ uint32_t
+ reg() const
+ { return this->reg_; }
+
+ protected:
+ // Arm V4BX stubs are created via a stub factory. So these are protected.
+ Arm_v4bx_stub(const Stub_template* stub_template, const uint32_t reg)
+ : Stub(stub_template), reg_(reg)
+ { }
+
+ friend class Stub_factory;
+
+ // Return the relocation target address of the i-th relocation in the
+ // stub.
+ Arm_address
+ do_reloc_target(size_t)
+ { gold_unreachable(); }
+
+ // This may be overridden in the child class.
+ virtual void
+ do_write(unsigned char* view, section_size_type view_size, bool big_endian)
+ {
+ if (big_endian)
+ this->do_fixed_endian_v4bx_write<true>(view, view_size);
+ else
+ this->do_fixed_endian_v4bx_write<false>(view, view_size);
+ }
+
+ private:
+ // A template to implement do_write.
+ template<bool big_endian>
+ void inline
+ do_fixed_endian_v4bx_write(unsigned char* view, section_size_type)
+ {
+ const Insn_template* insns = this->stub_template()->insns();
+ elfcpp::Swap<32, big_endian>::writeval(view,
+ (insns[0].data()
+ + (this->reg_ << 16)));
+ view += insns[0].size();
+ elfcpp::Swap<32, big_endian>::writeval(view,
+ (insns[1].data() + this->reg_));
+ view += insns[1].size();
+ elfcpp::Swap<32, big_endian>::writeval(view,
+ (insns[2].data() + this->reg_));
+ }
+
+ // A register index (r0-r14), which is associated with the stub.
+ uint32_t reg_;
};
// Stub factory class.
return new Reloc_stub(this->stub_templates_[stub_type]);
}
+ // Make a Cortex-A8 stub.
+ Cortex_a8_stub*
+ make_cortex_a8_stub(Stub_type stub_type, Relobj* relobj, unsigned int shndx,
+ Arm_address source, Arm_address destination,
+ uint32_t original_insn) const
+ {
+ gold_assert(stub_type >= arm_stub_cortex_a8_first
+ && stub_type <= arm_stub_cortex_a8_last);
+ return new Cortex_a8_stub(this->stub_templates_[stub_type], relobj, shndx,
+ source, destination, original_insn);
+ }
+
+ // Make an ARM V4BX relocation stub.
+ // This method creates a stub from the arm_stub_v4_veneer_bx template only.
+ Arm_v4bx_stub*
+ make_arm_v4bx_stub(uint32_t reg) const
+ {
+ gold_assert(reg < 0xf);
+ return new Arm_v4bx_stub(this->stub_templates_[arm_stub_v4_veneer_bx],
+ reg);
+ }
+
private:
// Constructor and destructor are protected since we only return a single
// instance created in Stub_factory::get_instance().
const Stub_template* stub_templates_[arm_stub_type_last+1];
};
-// Utilities for manipulating integers of up to 32-bits
+// A class to hold stubs for the ARM target.
-namespace utils
+template<bool big_endian>
+class Stub_table : public Output_data
{
- // Sign extend an n-bit unsigned integer stored in an uint32_t into
- // an int32_t. NO_BITS must be between 1 to 32.
- template<int no_bits>
- static inline int32_t
- sign_extend(uint32_t bits)
+ public:
+ Stub_table(Arm_input_section<big_endian>* owner)
+ : Output_data(), owner_(owner), reloc_stubs_(), reloc_stubs_size_(0),
+ reloc_stubs_addralign_(1), cortex_a8_stubs_(), arm_v4bx_stubs_(0xf),
+ prev_data_size_(0), prev_addralign_(1)
+ { }
+
+ ~Stub_table()
+ { }
+
+ // Owner of this stub table.
+ Arm_input_section<big_endian>*
+ owner() const
+ { return this->owner_; }
+
+ // Whether this stub table is empty.
+ bool
+ empty() const
{
- gold_assert(no_bits >= 0 && no_bits <= 32);
- if (no_bits == 32)
- return static_cast<int32_t>(bits);
- uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits);
- bits &= mask;
- uint32_t top_bit = 1U << (no_bits - 1);
- int32_t as_signed = static_cast<int32_t>(bits);
- return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed;
+ return (this->reloc_stubs_.empty()
+ && this->cortex_a8_stubs_.empty()
+ && this->arm_v4bx_stubs_.empty());
}
- // Detects overflow of an NO_BITS integer stored in a uint32_t.
- template<int no_bits>
- static inline bool
- has_overflow(uint32_t bits)
+ // Return the current data size.
+ off_t
+ current_data_size() const
+ { return this->current_data_size_for_child(); }
+
+ // Add a STUB with using KEY. Caller is reponsible for avoid adding
+ // if already a STUB with the same key has been added.
+ void
+ add_reloc_stub(Reloc_stub* stub, const Reloc_stub::Key& key)
{
- gold_assert(no_bits >= 0 && no_bits <= 32);
- if (no_bits == 32)
- return false;
- int32_t max = (1 << (no_bits - 1)) - 1;
- int32_t min = -(1 << (no_bits - 1));
- int32_t as_signed = static_cast<int32_t>(bits);
- return as_signed > max || as_signed < min;
+ const Stub_template* stub_template = stub->stub_template();
+ gold_assert(stub_template->type() == key.stub_type());
+ this->reloc_stubs_[key] = stub;
+
+ // Assign stub offset early. We can do this because we never remove
+ // reloc stubs and they are in the beginning of the stub table.
+ uint64_t align = stub_template->alignment();
+ this->reloc_stubs_size_ = align_address(this->reloc_stubs_size_, align);
+ stub->set_offset(this->reloc_stubs_size_);
+ this->reloc_stubs_size_ += stub_template->size();
+ this->reloc_stubs_addralign_ =
+ std::max(this->reloc_stubs_addralign_, align);
}
- // Detects overflow of an NO_BITS integer stored in a uint32_t when it
- // fits in the given number of bits as either a signed or unsigned value.
- // For example, has_signed_unsigned_overflow<8> would check
- // -128 <= bits <= 255
- template<int no_bits>
- static inline bool
- has_signed_unsigned_overflow(uint32_t bits)
+ // Add a Cortex-A8 STUB that fixes up a THUMB branch at ADDRESS.
+ // Caller is reponsible for avoid adding if already a STUB with the same
+ // address has been added.
+ void
+ add_cortex_a8_stub(Arm_address address, Cortex_a8_stub* stub)
{
- gold_assert(no_bits >= 2 && no_bits <= 32);
- if (no_bits == 32)
- return false;
- int32_t max = static_cast<int32_t>((1U << no_bits) - 1);
- int32_t min = -(1 << (no_bits - 1));
- int32_t as_signed = static_cast<int32_t>(bits);
- return as_signed > max || as_signed < min;
+ std::pair<Arm_address, Cortex_a8_stub*> value(address, stub);
+ this->cortex_a8_stubs_.insert(value);
}
- // Select bits from A and B using bits in MASK. For each n in [0..31],
- // the n-th bit in the result is chosen from the n-th bits of A and B.
- // A zero selects A and a one selects B.
- static inline uint32_t
- bit_select(uint32_t a, uint32_t b, uint32_t mask)
- { return (a & ~mask) | (b & mask); }
-};
-
-template<bool big_endian>
-class Target_arm : public Sized_target<32, big_endian>
-{
- public:
- typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
- Reloc_section;
-
- Target_arm()
- : Sized_target<32, big_endian>(&arm_info),
- got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
- copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL),
- may_use_blx_(true), should_force_pic_veneer_(false)
- { }
-
- // Whether we can use BLX.
- bool
- may_use_blx() const
- { return this->may_use_blx_; }
-
- // Set use-BLX flag.
+ // Add an ARM V4BX relocation stub. A register index will be retrieved
+ // from the stub.
void
- set_may_use_blx(bool value)
- { this->may_use_blx_ = value; }
-
- // Whether we force PCI branch veneers.
- bool
- should_force_pic_veneer() const
- { return this->should_force_pic_veneer_; }
+ add_arm_v4bx_stub(Arm_v4bx_stub* stub)
+ {
+ gold_assert(stub != NULL && this->arm_v4bx_stubs_[stub->reg()] == NULL);
+ this->arm_v4bx_stubs_[stub->reg()] = stub;
+ }
- // Set PIC veneer flag.
+ // Remove all Cortex-A8 stubs.
void
- set_should_force_pic_veneer(bool value)
- { this->should_force_pic_veneer_ = value; }
-
- // Whether we use THUMB-2 instructions.
- bool
- using_thumb2() const
+ remove_all_cortex_a8_stubs();
+
+ // Look up a relocation stub using KEY. Return NULL if there is none.
+ Reloc_stub*
+ find_reloc_stub(const Reloc_stub::Key& key) const
{
- // FIXME: This should not hard-coded.
- return false;
+ typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.find(key);
+ return (p != this->reloc_stubs_.end()) ? p->second : NULL;
}
- // Whether we use THUMB/THUMB-2 instructions only.
- bool
- using_thumb_only() const
+ // Look up an arm v4bx relocation stub using the register index.
+ // Return NULL if there is none.
+ Arm_v4bx_stub*
+ find_arm_v4bx_stub(const uint32_t reg) const
{
- // FIXME: This should not hard-coded.
- return false;
+ gold_assert(reg < 0xf);
+ return this->arm_v4bx_stubs_[reg];
}
- // Process the relocations to determine unreferenced sections for
- // garbage collection.
+ // Relocate stubs in this stub table.
void
- gc_process_relocs(const General_options& options,
- Symbol_table* symtab,
- Layout* layout,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- unsigned int sh_type,
- const unsigned char* prelocs,
- size_t reloc_count,
- Output_section* output_section,
- bool needs_special_offset_handling,
- size_t local_symbol_count,
- const unsigned char* plocal_symbols);
+ relocate_stubs(const Relocate_info<32, big_endian>*,
+ Target_arm<big_endian>*, Output_section*,
+ unsigned char*, Arm_address, section_size_type);
- // Scan the relocations to look for symbol adjustments.
- void
- scan_relocs(const General_options& options,
- Symbol_table* symtab,
- Layout* layout,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- unsigned int sh_type,
- const unsigned char* prelocs,
- size_t reloc_count,
- Output_section* output_section,
- bool needs_special_offset_handling,
- size_t local_symbol_count,
- const unsigned char* plocal_symbols);
+ // Update data size and alignment at the end of a relaxation pass. Return
+ // true if either data size or alignment is different from that of the
+ // previous relaxation pass.
+ bool
+ update_data_size_and_addralign();
- // Finalize the sections.
+ // Finalize stubs. Set the offsets of all stubs and mark input sections
+ // needing the Cortex-A8 workaround.
+ void
+ finalize_stubs();
+
+ // Apply Cortex-A8 workaround to an address range.
void
- do_finalize_sections(Layout*);
+ apply_cortex_a8_workaround_to_address_range(Target_arm<big_endian>*,
+ unsigned char*, Arm_address,
+ section_size_type);
- // Return the value to use for a dynamic symbol which requires special
- // treatment.
+ protected:
+ // Write out section contents.
+ void
+ do_write(Output_file*);
+
+ // Return the required alignment.
uint64_t
- do_dynsym_value(const Symbol*) const;
+ do_addralign() const
+ { return this->prev_addralign_; }
- // Relocate a section.
+ // Reset address and file offset.
void
- relocate_section(const Relocate_info<32, big_endian>*,
- unsigned int sh_type,
- const unsigned char* prelocs,
- size_t reloc_count,
- Output_section* output_section,
- bool needs_special_offset_handling,
- unsigned char* view,
- elfcpp::Elf_types<32>::Elf_Addr view_address,
- section_size_type view_size,
- const Reloc_symbol_changes*);
+ do_reset_address_and_file_offset()
+ { this->set_current_data_size_for_child(this->prev_data_size_); }
- // Scan the relocs during a relocatable link.
+ // Set final data size.
void
- scan_relocatable_relocs(const General_options& options,
- Symbol_table* symtab,
- Layout* layout,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- unsigned int sh_type,
- const unsigned char* prelocs,
- size_t reloc_count,
- Output_section* output_section,
- bool needs_special_offset_handling,
- size_t local_symbol_count,
- const unsigned char* plocal_symbols,
- Relocatable_relocs*);
-
- // Relocate a section during a relocatable link.
+ set_final_data_size()
+ { this->set_data_size(this->current_data_size()); }
+
+ private:
+ // Relocate one stub.
void
- relocate_for_relocatable(const Relocate_info<32, big_endian>*,
- unsigned int sh_type,
- const unsigned char* prelocs,
- size_t reloc_count,
- Output_section* output_section,
- off_t offset_in_output_section,
- const Relocatable_relocs*,
- unsigned char* view,
- elfcpp::Elf_types<32>::Elf_Addr view_address,
- section_size_type view_size,
- unsigned char* reloc_view,
- section_size_type reloc_view_size);
+ relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
+ Target_arm<big_endian>*, Output_section*,
+ unsigned char*, Arm_address, section_size_type);
+
+ // Unordered map of relocation stubs.
+ typedef
+ Unordered_map<Reloc_stub::Key, Reloc_stub*, Reloc_stub::Key::hash,
+ Reloc_stub::Key::equal_to>
+ Reloc_stub_map;
+
+ // List of Cortex-A8 stubs ordered by addresses of branches being
+ // fixed up in output.
+ typedef std::map<Arm_address, Cortex_a8_stub*> Cortex_a8_stub_list;
+ // List of Arm V4BX relocation stubs ordered by associated registers.
+ typedef std::vector<Arm_v4bx_stub*> Arm_v4bx_stub_list;
+
+ // Owner of this stub table.
+ Arm_input_section<big_endian>* owner_;
+ // The relocation stubs.
+ Reloc_stub_map reloc_stubs_;
+ // Size of reloc stubs.
+ off_t reloc_stubs_size_;
+ // Maximum address alignment of reloc stubs.
+ uint64_t reloc_stubs_addralign_;
+ // The cortex_a8_stubs.
+ Cortex_a8_stub_list cortex_a8_stubs_;
+ // The Arm V4BX relocation stubs.
+ Arm_v4bx_stub_list arm_v4bx_stubs_;
+ // data size of this in the previous pass.
+ off_t prev_data_size_;
+ // address alignment of this in the previous pass.
+ uint64_t prev_addralign_;
+};
- // Return whether SYM is defined by the ABI.
- bool
- do_is_defined_by_abi(Symbol* sym) const
- { return strcmp(sym->name(), "__tls_get_addr") == 0; }
+// Arm_exidx_cantunwind class. This represents an EXIDX_CANTUNWIND entry
+// we add to the end of an EXIDX input section that goes into the output.
- // Return the size of the GOT section.
- section_size_type
- got_size()
- {
- gold_assert(this->got_ != NULL);
- return this->got_->data_size();
- }
+class Arm_exidx_cantunwind : public Output_section_data
+{
+ public:
+ Arm_exidx_cantunwind(Relobj* relobj, unsigned int shndx)
+ : Output_section_data(8, 4, true), relobj_(relobj), shndx_(shndx)
+ { }
- // Map platform-specific reloc types
- static unsigned int
- get_real_reloc_type (unsigned int r_type);
+ // Return the object containing the section pointed by this.
+ Relobj*
+ relobj() const
+ { return this->relobj_; }
- // Get the default ARM target.
- static const Target_arm<big_endian>&
- default_target()
+ // Return the section index of the section pointed by this.
+ unsigned int
+ shndx() const
+ { return this->shndx_; }
+
+ protected:
+ void
+ do_write(Output_file* of)
{
- gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
- && parameters->target().is_big_endian() == big_endian);
- return static_cast<const Target_arm<big_endian>&>(parameters->target());
+ if (parameters->target().is_big_endian())
+ this->do_fixed_endian_write<true>(of);
+ else
+ this->do_fixed_endian_write<false>(of);
}
private:
- // The class which scans relocations.
- class Scan
- {
- public:
- Scan()
- : issued_non_pic_error_(false)
- { }
-
- inline void
- local(const General_options& options, Symbol_table* symtab,
- Layout* layout, Target_arm* target,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- Output_section* output_section,
- const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
- const elfcpp::Sym<32, big_endian>& lsym);
+ // Implement do_write for a given endianness.
+ template<bool big_endian>
+ void inline
+ do_fixed_endian_write(Output_file*);
+
+ // The object containing the section pointed by this.
+ Relobj* relobj_;
+ // The section index of the section pointed by this.
+ unsigned int shndx_;
+};
- inline void
- global(const General_options& options, Symbol_table* symtab,
- Layout* layout, Target_arm* target,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- Output_section* output_section,
- const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
- Symbol* gsym);
+// During EXIDX coverage fix-up, we compact an EXIDX section. The
+// Offset map is used to map input section offset within the EXIDX section
+// to the output offset from the start of this EXIDX section.
- private:
- static void
- unsupported_reloc_local(Sized_relobj<32, big_endian>*,
- unsigned int r_type);
+typedef std::map<section_offset_type, section_offset_type>
+ Arm_exidx_section_offset_map;
- static void
- unsupported_reloc_global(Sized_relobj<32, big_endian>*,
- unsigned int r_type, Symbol*);
+// Arm_exidx_merged_section class. This represents an EXIDX input section
+// with some of its entries merged.
- void
- check_non_pic(Relobj*, unsigned int r_type);
+class Arm_exidx_merged_section : public Output_relaxed_input_section
+{
+ public:
+ // Constructor for Arm_exidx_merged_section.
+ // EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
+ // SECTION_OFFSET_MAP points to a section offset map describing how
+ // parts of the input section are mapped to output. DELETED_BYTES is
+ // the number of bytes deleted from the EXIDX input section.
+ Arm_exidx_merged_section(
+ const Arm_exidx_input_section& exidx_input_section,
+ const Arm_exidx_section_offset_map& section_offset_map,
+ uint32_t deleted_bytes);
+
+ // Return the original EXIDX input section.
+ const Arm_exidx_input_section&
+ exidx_input_section() const
+ { return this->exidx_input_section_; }
+
+ // Return the section offset map.
+ const Arm_exidx_section_offset_map&
+ section_offset_map() const
+ { return this->section_offset_map_; }
- // Almost identical to Symbol::needs_plt_entry except that it also
- // handles STT_ARM_TFUNC.
- static bool
- symbol_needs_plt_entry(const Symbol* sym)
- {
- // An undefined symbol from an executable does not need a PLT entry.
- if (sym->is_undefined() && !parameters->options().shared())
- return false;
+ protected:
+ // Write merged section into file OF.
+ void
+ do_write(Output_file* of);
- return (!parameters->doing_static_link()
- && (sym->type() == elfcpp::STT_FUNC
- || sym->type() == elfcpp::STT_ARM_TFUNC)
- && (sym->is_from_dynobj()
- || sym->is_undefined()
- || sym->is_preemptible()));
- }
+ bool
+ do_output_offset(const Relobj*, unsigned int, section_offset_type,
+ section_offset_type*) const;
- // Whether we have issued an error about a non-PIC compilation.
- bool issued_non_pic_error_;
- };
+ private:
+ // Original EXIDX input section.
+ const Arm_exidx_input_section& exidx_input_section_;
+ // Section offset map.
+ const Arm_exidx_section_offset_map& section_offset_map_;
+};
- // The class which implements relocation.
- class Relocate
- {
- public:
- Relocate()
- { }
+// A class to wrap an ordinary input section containing executable code.
- ~Relocate()
- { }
+template<bool big_endian>
+class Arm_input_section : public Output_relaxed_input_section
+{
+ public:
+ Arm_input_section(Relobj* relobj, unsigned int shndx)
+ : Output_relaxed_input_section(relobj, shndx, 1),
+ original_addralign_(1), original_size_(0), stub_table_(NULL)
+ { }
- // Return whether the static relocation needs to be applied.
- inline bool
- should_apply_static_reloc(const Sized_symbol<32>* gsym,
- int ref_flags,
- bool is_32bit,
- Output_section* output_section);
+ ~Arm_input_section()
+ { }
- // Do a relocation. Return false if the caller should not issue
- // any warnings about this relocation.
- inline bool
- relocate(const Relocate_info<32, big_endian>*, Target_arm*,
- Output_section*, size_t relnum,
- const elfcpp::Rel<32, big_endian>&,
- unsigned int r_type, const Sized_symbol<32>*,
- const Symbol_value<32>*,
- unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
- section_size_type);
+ // Initialize.
+ void
+ init();
+
+ // Whether this is a stub table owner.
+ bool
+ is_stub_table_owner() const
+ { return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
- // Return whether we want to pass flag NON_PIC_REF for this
- // reloc.
- static inline bool
- reloc_is_non_pic (unsigned int r_type)
- {
- switch (r_type)
- {
- case elfcpp::R_ARM_REL32:
- case elfcpp::R_ARM_THM_CALL:
- case elfcpp::R_ARM_CALL:
- case elfcpp::R_ARM_JUMP24:
- case elfcpp::R_ARM_PREL31:
- case elfcpp::R_ARM_THM_ABS5:
- case elfcpp::R_ARM_ABS8:
- case elfcpp::R_ARM_ABS12:
- case elfcpp::R_ARM_ABS16:
- case elfcpp::R_ARM_BASE_ABS:
- return true;
- default:
- return false;
- }
- }
- };
+ // Return the stub table.
+ Stub_table<big_endian>*
+ stub_table() const
+ { return this->stub_table_; }
- // A class which returns the size required for a relocation type,
- // used while scanning relocs during a relocatable link.
- class Relocatable_size_for_reloc
- {
- public:
- unsigned int
- get_size_for_reloc(unsigned int, Relobj*);
- };
+ // Set the stub_table.
+ void
+ set_stub_table(Stub_table<big_endian>* stub_table)
+ { this->stub_table_ = stub_table; }
- // Get the GOT section, creating it if necessary.
- Output_data_got<32, big_endian>*
- got_section(Symbol_table*, Layout*);
+ // Downcast a base pointer to an Arm_input_section pointer. This is
+ // not type-safe but we only use Arm_input_section not the base class.
+ static Arm_input_section<big_endian>*
+ as_arm_input_section(Output_relaxed_input_section* poris)
+ { return static_cast<Arm_input_section<big_endian>*>(poris); }
- // Get the GOT PLT section.
- Output_data_space*
- got_plt_section() const
- {
- gold_assert(this->got_plt_ != NULL);
- return this->got_plt_;
- }
+ // Return the original size of the section.
+ uint32_t
+ original_size() const
+ { return this->original_size_; }
- // Create a PLT entry for a global symbol.
+ protected:
+ // Write data to output file.
void
- make_plt_entry(Symbol_table*, Layout*, Symbol*);
+ do_write(Output_file*);
- // Get the PLT section.
- const Output_data_plt_arm<big_endian>*
- plt_section() const
+ // Return required alignment of this.
+ uint64_t
+ do_addralign() const
{
- gold_assert(this->plt_ != NULL);
- return this->plt_;
+ if (this->is_stub_table_owner())
+ return std::max(this->stub_table_->addralign(),
+ static_cast<uint64_t>(this->original_addralign_));
+ else
+ return this->original_addralign_;
}
- // Get the dynamic reloc section, creating it if necessary.
- Reloc_section*
- rel_dyn_section(Layout*);
+ // Finalize data size.
+ void
+ set_final_data_size();
- // Return true if the symbol may need a COPY relocation.
- // References from an executable object to non-function symbols
- // defined in a dynamic object may need a COPY relocation.
+ // Reset address and file offset.
+ void
+ do_reset_address_and_file_offset();
+
+ // Output offset.
bool
- may_need_copy_reloc(Symbol* gsym)
+ do_output_offset(const Relobj* object, unsigned int shndx,
+ section_offset_type offset,
+ section_offset_type* poutput) const
{
- return (gsym->type() != elfcpp::STT_ARM_TFUNC
- && gsym->may_need_copy_reloc());
+ if ((object == this->relobj())
+ && (shndx == this->shndx())
+ && (offset >= 0)
+ && (offset <=
+ convert_types<section_offset_type, uint32_t>(this->original_size_)))
+ {
+ *poutput = offset;
+ return true;
+ }
+ else
+ return false;
}
- // Add a potential copy relocation.
+ private:
+ // Copying is not allowed.
+ Arm_input_section(const Arm_input_section&);
+ Arm_input_section& operator=(const Arm_input_section&);
+
+ // Address alignment of the original input section.
+ uint32_t original_addralign_;
+ // Section size of the original input section.
+ uint32_t original_size_;
+ // Stub table.
+ Stub_table<big_endian>* stub_table_;
+};
+
+// Arm_exidx_fixup class. This is used to define a number of methods
+// and keep states for fixing up EXIDX coverage.
+
+class Arm_exidx_fixup
+{
+ public:
+ Arm_exidx_fixup(Output_section* exidx_output_section,
+ bool merge_exidx_entries = true)
+ : exidx_output_section_(exidx_output_section), last_unwind_type_(UT_NONE),
+ last_inlined_entry_(0), last_input_section_(NULL),
+ section_offset_map_(NULL), first_output_text_section_(NULL),
+ merge_exidx_entries_(merge_exidx_entries)
+ { }
+
+ ~Arm_exidx_fixup()
+ { delete this->section_offset_map_; }
+
+ // Process an EXIDX section for entry merging. Return number of bytes to
+ // be deleted in output. If parts of the input EXIDX section are merged
+ // a heap allocated Arm_exidx_section_offset_map is store in the located
+ // PSECTION_OFFSET_MAP. The caller owns the map and is reponsible for
+ // releasing it.
+ template<bool big_endian>
+ uint32_t
+ process_exidx_section(const Arm_exidx_input_section* exidx_input_section,
+ Arm_exidx_section_offset_map** psection_offset_map);
+
+ // Append an EXIDX_CANTUNWIND entry pointing at the end of the last
+ // input section, if there is not one already.
void
- copy_reloc(Symbol_table* symtab, Layout* layout,
- Sized_relobj<32, big_endian>* object,
- unsigned int shndx, Output_section* output_section,
- Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
- {
- this->copy_relocs_.copy_reloc(symtab, layout,
- symtab->get_sized_symbol<32>(sym),
- object, shndx, output_section, reloc,
- this->rel_dyn_section(layout));
- }
+ add_exidx_cantunwind_as_needed();
- // Information about this specific target which we pass to the
- // general Target structure.
- static const Target::Target_info arm_info;
+ // Return the output section for the text section which is linked to the
+ // first exidx input in output.
+ Output_section*
+ first_output_text_section() const
+ { return this->first_output_text_section_; }
- // The types of GOT entries needed for this platform.
- enum Got_type
+ private:
+ // Copying is not allowed.
+ Arm_exidx_fixup(const Arm_exidx_fixup&);
+ Arm_exidx_fixup& operator=(const Arm_exidx_fixup&);
+
+ // Type of EXIDX unwind entry.
+ enum Unwind_type
{
- GOT_TYPE_STANDARD = 0 // GOT entry for a regular symbol
+ // No type.
+ UT_NONE,
+ // EXIDX_CANTUNWIND.
+ UT_EXIDX_CANTUNWIND,
+ // Inlined entry.
+ UT_INLINED_ENTRY,
+ // Normal entry.
+ UT_NORMAL_ENTRY,
};
- // The GOT section.
- Output_data_got<32, big_endian>* got_;
- // The PLT section.
- Output_data_plt_arm<big_endian>* plt_;
- // The GOT PLT section.
- Output_data_space* got_plt_;
- // The dynamic reloc section.
- Reloc_section* rel_dyn_;
- // Relocs saved to avoid a COPY reloc.
- Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
- // Space for variables copied with a COPY reloc.
- Output_data_space* dynbss_;
- // Whether we can use BLX.
- bool may_use_blx_;
- // Whether we force PIC branch veneers.
- bool should_force_pic_veneer_;
+ // Process an EXIDX entry. We only care about the second word of the
+ // entry. Return true if the entry can be deleted.
+ bool
+ process_exidx_entry(uint32_t second_word);
+
+ // Update the current section offset map during EXIDX section fix-up.
+ // If there is no map, create one. INPUT_OFFSET is the offset of a
+ // reference point, DELETED_BYTES is the number of deleted by in the
+ // section so far. If DELETE_ENTRY is true, the reference point and
+ // all offsets after the previous reference point are discarded.
+ void
+ update_offset_map(section_offset_type input_offset,
+ section_size_type deleted_bytes, bool delete_entry);
+
+ // EXIDX output section.
+ Output_section* exidx_output_section_;
+ // Unwind type of the last EXIDX entry processed.
+ Unwind_type last_unwind_type_;
+ // Last seen inlined EXIDX entry.
+ uint32_t last_inlined_entry_;
+ // Last processed EXIDX input section.
+ const Arm_exidx_input_section* last_input_section_;
+ // Section offset map created in process_exidx_section.
+ Arm_exidx_section_offset_map* section_offset_map_;
+ // Output section for the text section which is linked to the first exidx
+ // input in output.
+ Output_section* first_output_text_section_;
+
+ bool merge_exidx_entries_;
};
+// Arm output section class. This is defined mainly to add a number of
+// stub generation methods.
+
template<bool big_endian>
-const Target::Target_info Target_arm<big_endian>::arm_info =
+class Arm_output_section : public Output_section
{
- 32, // size
- big_endian, // is_big_endian
- elfcpp::EM_ARM, // machine_code
- false, // has_make_symbol
- false, // has_resolve
- false, // has_code_fill
- true, // is_default_stack_executable
- '\0', // wrap_char
- "/usr/lib/libc.so.1", // dynamic_linker
- 0x8000, // default_text_segment_address
- 0x1000, // abi_pagesize (overridable by -z max-page-size)
- 0x1000, // common_pagesize (overridable by -z common-page-size)
- elfcpp::SHN_UNDEF, // small_common_shndx
- elfcpp::SHN_UNDEF, // large_common_shndx
- 0, // small_common_section_flags
- 0 // large_common_section_flags
+ public:
+ typedef std::vector<std::pair<Relobj*, unsigned int> > Text_section_list;
+
+ Arm_output_section(const char* name, elfcpp::Elf_Word type,
+ elfcpp::Elf_Xword flags)
+ : Output_section(name, type, flags)
+ {
+ if (type == elfcpp::SHT_ARM_EXIDX)
+ this->set_always_keeps_input_sections();
+ }
+
+ ~Arm_output_section()
+ { }
+
+ // Group input sections for stub generation.
+ void
+ group_sections(section_size_type, bool, Target_arm<big_endian>*);
+
+ // Downcast a base pointer to an Arm_output_section pointer. This is
+ // not type-safe but we only use Arm_output_section not the base class.
+ static Arm_output_section<big_endian>*
+ as_arm_output_section(Output_section* os)
+ { return static_cast<Arm_output_section<big_endian>*>(os); }
+
+ // Append all input text sections in this into LIST.
+ void
+ append_text_sections_to_list(Text_section_list* list);
+
+ // Fix EXIDX coverage of this EXIDX output section. SORTED_TEXT_SECTION
+ // is a list of text input sections sorted in ascending order of their
+ // output addresses.
+ void
+ fix_exidx_coverage(Layout* layout,
+ const Text_section_list& sorted_text_section,
+ Symbol_table* symtab,
+ bool merge_exidx_entries);
+
+ // Link an EXIDX section into its corresponding text section.
+ void
+ set_exidx_section_link();
+
+ private:
+ // For convenience.
+ typedef Output_section::Input_section Input_section;
+ typedef Output_section::Input_section_list Input_section_list;
+
+ // Create a stub group.
+ void create_stub_group(Input_section_list::const_iterator,
+ Input_section_list::const_iterator,
+ Input_section_list::const_iterator,
+ Target_arm<big_endian>*,
+ std::vector<Output_relaxed_input_section*>*);
};
-// Arm relocate functions class
-//
+// Arm_exidx_input_section class. This represents an EXIDX input section.
-template<bool big_endian>
-class Arm_relocate_functions : public Relocate_functions<32, big_endian>
+class Arm_exidx_input_section
{
public:
- typedef enum
- {
- STATUS_OKAY, // No error during relocation.
- STATUS_OVERFLOW, // Relocation oveflow.
- STATUS_BAD_RELOC // Relocation cannot be applied.
- } Status;
+ static const section_offset_type invalid_offset =
+ static_cast<section_offset_type>(-1);
+
+ Arm_exidx_input_section(Relobj* relobj, unsigned int shndx,
+ unsigned int link, uint32_t size, uint32_t addralign)
+ : relobj_(relobj), shndx_(shndx), link_(link), size_(size),
+ addralign_(addralign), has_errors_(false)
+ { }
+
+ ~Arm_exidx_input_section()
+ { }
+
+ // Accessors: This is a read-only class.
+
+ // Return the object containing this EXIDX input section.
+ Relobj*
+ relobj() const
+ { return this->relobj_; }
+
+ // Return the section index of this EXIDX input section.
+ unsigned int
+ shndx() const
+ { return this->shndx_; }
+
+ // Return the section index of linked text section in the same object.
+ unsigned int
+ link() const
+ { return this->link_; }
+
+ // Return size of the EXIDX input section.
+ uint32_t
+ size() const
+ { return this->size_; }
+
+ // Reutnr address alignment of EXIDX input section.
+ uint32_t
+ addralign() const
+ { return this->addralign_; }
+
+ // Whether there are any errors in the EXIDX input section.
+ bool
+ has_errors() const
+ { return this->has_errors_; }
+
+ // Set has-errors flag.
+ void
+ set_has_errors()
+ { this->has_errors_ = true; }
private:
- typedef Relocate_functions<32, big_endian> Base;
- typedef Arm_relocate_functions<big_endian> This;
+ // Object containing this.
+ Relobj* relobj_;
+ // Section index of this.
+ unsigned int shndx_;
+ // text section linked to this in the same object.
+ unsigned int link_;
+ // Size of this. For ARM 32-bit is sufficient.
+ uint32_t size_;
+ // Address alignment of this. For ARM 32-bit is sufficient.
+ uint32_t addralign_;
+ // Whether this has any errors.
+ bool has_errors_;
+};
- // Get an symbol value of *PSYMVAL with an ADDEND. This is a wrapper
- // to Symbol_value::value(). If HAS_THUMB_BIT is true, that LSB is used
- // to distinguish ARM and THUMB functions and it is treated specially.
- static inline Symbol_value<32>::Value
- arm_symbol_value (const Sized_relobj<32, big_endian> *object,
- const Symbol_value<32>* psymval,
- Symbol_value<32>::Value addend,
- bool has_thumb_bit)
- {
- typedef Symbol_value<32>::Value Valtype;
+// Arm_relobj class.
- if (has_thumb_bit)
- {
- Valtype raw = psymval->value(object, 0);
- Valtype thumb_bit = raw & 1;
- return ((raw & ~((Valtype) 1)) + addend) | thumb_bit;
- }
- else
- return psymval->value(object, addend);
- }
+template<bool big_endian>
+class Arm_relobj : public Sized_relobj<32, big_endian>
+{
+ public:
+ static const Arm_address invalid_address = static_cast<Arm_address>(-1);
- // Encoding of imm16 argument for movt and movw ARM instructions
- // from ARM ARM:
- //
- // imm16 := imm4 | imm12
- //
- // f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0
- // +-------+---------------+-------+-------+-----------------------+
- // | | |imm4 | |imm12 |
- // +-------+---------------+-------+-------+-----------------------+
+ Arm_relobj(const std::string& name, Input_file* input_file, off_t offset,
+ const typename elfcpp::Ehdr<32, big_endian>& ehdr)
+ : Sized_relobj<32, big_endian>(name, input_file, offset, ehdr),
+ stub_tables_(), local_symbol_is_thumb_function_(),
+ attributes_section_data_(NULL), mapping_symbols_info_(),
+ section_has_cortex_a8_workaround_(NULL), exidx_section_map_(),
+ output_local_symbol_count_needs_update_(false),
+ merge_flags_and_attributes_(true)
+ { }
- // Extract the relocation addend from VAL based on the ARM
- // instruction encoding described above.
- static inline typename elfcpp::Swap<32, big_endian>::Valtype
- extract_arm_movw_movt_addend(
- typename elfcpp::Swap<32, big_endian>::Valtype val)
+ ~Arm_relobj()
+ { delete this->attributes_section_data_; }
+
+ // Return the stub table of the SHNDX-th section if there is one.
+ Stub_table<big_endian>*
+ stub_table(unsigned int shndx) const
{
- // According to the Elf ABI for ARM Architecture the immediate
- // field is sign-extended to form the addend.
- return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff));
+ gold_assert(shndx < this->stub_tables_.size());
+ return this->stub_tables_[shndx];
}
- // Insert X into VAL based on the ARM instruction encoding described
- // above.
- static inline typename elfcpp::Swap<32, big_endian>::Valtype
- insert_val_arm_movw_movt(
- typename elfcpp::Swap<32, big_endian>::Valtype val,
- typename elfcpp::Swap<32, big_endian>::Valtype x)
+ // Set STUB_TABLE to be the stub_table of the SHNDX-th section.
+ void
+ set_stub_table(unsigned int shndx, Stub_table<big_endian>* stub_table)
{
- val &= 0xfff0f000;
- val |= x & 0x0fff;
- val |= (x & 0xf000) << 4;
- return val;
+ gold_assert(shndx < this->stub_tables_.size());
+ this->stub_tables_[shndx] = stub_table;
}
- // Encoding of imm16 argument for movt and movw Thumb2 instructions
- // from ARM ARM:
- //
- // imm16 := imm4 | i | imm3 | imm8
- //
- // f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0
- // +---------+-+-----------+-------++-+-----+-------+---------------+
- // | |i| |imm4 || |imm3 | |imm8 |
- // +---------+-+-----------+-------++-+-----+-------+---------------+
-
- // Extract the relocation addend from VAL based on the Thumb2
- // instruction encoding described above.
- static inline typename elfcpp::Swap<32, big_endian>::Valtype
- extract_thumb_movw_movt_addend(
- typename elfcpp::Swap<32, big_endian>::Valtype val)
+ // Whether a local symbol is a THUMB function. R_SYM is the symbol table
+ // index. This is only valid after do_count_local_symbol is called.
+ bool
+ local_symbol_is_thumb_function(unsigned int r_sym) const
{
- // According to the Elf ABI for ARM Architecture the immediate
- // field is sign-extended to form the addend.
- return utils::sign_extend<16>(((val >> 4) & 0xf000)
- | ((val >> 15) & 0x0800)
- | ((val >> 4) & 0x0700)
- | (val & 0x00ff));
+ gold_assert(r_sym < this->local_symbol_is_thumb_function_.size());
+ return this->local_symbol_is_thumb_function_[r_sym];
}
+
+ // Scan all relocation sections for stub generation.
+ void
+ scan_sections_for_stubs(Target_arm<big_endian>*, const Symbol_table*,
+ const Layout*);
- // Insert X into VAL based on the Thumb2 instruction encoding
- // described above.
- static inline typename elfcpp::Swap<32, big_endian>::Valtype
- insert_val_thumb_movw_movt(
- typename elfcpp::Swap<32, big_endian>::Valtype val,
- typename elfcpp::Swap<32, big_endian>::Valtype x)
+ // Convert regular input section with index SHNDX to a relaxed section.
+ void
+ convert_input_section_to_relaxed_section(unsigned shndx)
{
- val &= 0xfbf08f00;
- val |= (x & 0xf000) << 4;
- val |= (x & 0x0800) << 15;
- val |= (x & 0x0700) << 4;
- val |= (x & 0x00ff);
- return val;
+ // The stubs have relocations and we need to process them after writing
+ // out the stubs. So relocation now must follow section write.
+ this->set_section_offset(shndx, -1ULL);
+ this->set_relocs_must_follow_section_writes();
}
- // FIXME: This probably only works for Android on ARM v5te. We should
- // following GNU ld for the general case.
- template<unsigned r_type>
- static inline typename This::Status
- arm_branch_common(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address,
- bool has_thumb_bit)
+ // Downcast a base pointer to an Arm_relobj pointer. This is
+ // not type-safe but we only use Arm_relobj not the base class.
+ static Arm_relobj<big_endian>*
+ as_arm_relobj(Relobj* relobj)
+ { return static_cast<Arm_relobj<big_endian>*>(relobj); }
+
+ // Processor-specific flags in ELF file header. This is valid only after
+ // reading symbols.
+ elfcpp::Elf_Word
+ processor_specific_flags() const
+ { return this->processor_specific_flags_; }
+
+ // Attribute section data This is the contents of the .ARM.attribute section
+ // if there is one.
+ const Attributes_section_data*
+ attributes_section_data() const
+ { return this->attributes_section_data_; }
+
+ // Mapping symbol location.
+ typedef std::pair<unsigned int, Arm_address> Mapping_symbol_position;
+
+ // Functor for STL container.
+ struct Mapping_symbol_position_less
{
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
-
- bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
- && ((val & 0x0f000000UL) == 0x0a000000UL);
- bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
- bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
- && ((val & 0x0f000000UL) == 0x0b000000UL);
- bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
- bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
-
- if (r_type == elfcpp::R_ARM_CALL)
- {
- if (!insn_is_uncond_bl && !insn_is_blx)
- return This::STATUS_BAD_RELOC;
- }
- else if (r_type == elfcpp::R_ARM_JUMP24)
- {
- if (!insn_is_b && !insn_is_cond_bl)
- return This::STATUS_BAD_RELOC;
- }
- else if (r_type == elfcpp::R_ARM_PLT32)
- {
- if (!insn_is_any_branch)
- return This::STATUS_BAD_RELOC;
- }
- else
- gold_unreachable();
-
- Valtype addend = utils::sign_extend<26>(val << 2);
- Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
- - address);
-
- // If target has thumb bit set, we need to either turn the BL
- // into a BLX (for ARMv5 or above) or generate a stub.
- if (x & 1)
- {
- // Turn BL to BLX.
- if (insn_is_uncond_bl)
- val = (val & 0xffffff) | 0xfa000000 | ((x & 2) << 23);
- else
- return This::STATUS_BAD_RELOC;
- }
- else
- gold_assert(!insn_is_blx);
+ bool
+ operator()(const Mapping_symbol_position& p1,
+ const Mapping_symbol_position& p2) const
+ {
+ return (p1.first < p2.first
+ || (p1.first == p2.first && p1.second < p2.second));
+ }
+ };
+
+ // We only care about the first character of a mapping symbol, so
+ // we only store that instead of the whole symbol name.
+ typedef std::map<Mapping_symbol_position, char,
+ Mapping_symbol_position_less> Mapping_symbols_info;
- val = utils::bit_select(val, (x >> 2), 0xffffffUL);
- elfcpp::Swap<32, big_endian>::writeval(wv, val);
- return (utils::has_overflow<26>(x)
- ? This::STATUS_OVERFLOW : This::STATUS_OKAY);
+ // Whether a section contains any Cortex-A8 workaround.
+ bool
+ section_has_cortex_a8_workaround(unsigned int shndx) const
+ {
+ return (this->section_has_cortex_a8_workaround_ != NULL
+ && (*this->section_has_cortex_a8_workaround_)[shndx]);
}
-
- public:
-
- // R_ARM_ABS8: S + A
- static inline typename This::Status
- abs8(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval)
+
+ // Mark a section that has Cortex-A8 workaround.
+ void
+ mark_section_for_cortex_a8_workaround(unsigned int shndx)
{
- typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
- Reltype addend = utils::sign_extend<8>(val);
- Reltype x = This::arm_symbol_value(object, psymval, addend, false);
- val = utils::bit_select(val, x, 0xffU);
- elfcpp::Swap<8, big_endian>::writeval(wv, val);
- return (utils::has_signed_unsigned_overflow<8>(x)
- ? This::STATUS_OVERFLOW
- : This::STATUS_OKAY);
+ if (this->section_has_cortex_a8_workaround_ == NULL)
+ this->section_has_cortex_a8_workaround_ =
+ new std::vector<bool>(this->shnum(), false);
+ (*this->section_has_cortex_a8_workaround_)[shndx] = true;
}
- // R_ARM_THM_ABS5: S + A
- static inline typename This::Status
- thm_abs5(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval)
+ // Return the EXIDX section of an text section with index SHNDX or NULL
+ // if the text section has no associated EXIDX section.
+ const Arm_exidx_input_section*
+ exidx_input_section_by_link(unsigned int shndx) const
{
- typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
- Reltype addend = (val & 0x7e0U) >> 6;
- Reltype x = This::arm_symbol_value(object, psymval, addend, false);
- val = utils::bit_select(val, x << 6, 0x7e0U);
- elfcpp::Swap<16, big_endian>::writeval(wv, val);
- return (utils::has_overflow<5>(x)
- ? This::STATUS_OVERFLOW
- : This::STATUS_OKAY);
+ Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
+ return ((p != this->exidx_section_map_.end()
+ && p->second->link() == shndx)
+ ? p->second
+ : NULL);
}
- // R_ARM_ABS12: S + A
- static inline typename This::Status
- abs12(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval)
+ // Return the EXIDX section with index SHNDX or NULL if there is none.
+ const Arm_exidx_input_section*
+ exidx_input_section_by_shndx(unsigned shndx) const
{
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
- Reltype addend = val & 0x0fffU;
- Reltype x = This::arm_symbol_value(object, psymval, addend, false);
- val = utils::bit_select(val, x, 0x0fffU);
- elfcpp::Swap<32, big_endian>::writeval(wv, val);
- return (utils::has_overflow<12>(x)
- ? This::STATUS_OVERFLOW
- : This::STATUS_OKAY);
+ Exidx_section_map::const_iterator p = this->exidx_section_map_.find(shndx);
+ return ((p != this->exidx_section_map_.end()
+ && p->second->shndx() == shndx)
+ ? p->second
+ : NULL);
}
- // R_ARM_ABS16: S + A
- static inline typename This::Status
- abs16(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval)
+ // Whether output local symbol count needs updating.
+ bool
+ output_local_symbol_count_needs_update() const
+ { return this->output_local_symbol_count_needs_update_; }
+
+ // Set output_local_symbol_count_needs_update flag to be true.
+ void
+ set_output_local_symbol_count_needs_update()
+ { this->output_local_symbol_count_needs_update_ = true; }
+
+ // Update output local symbol count at the end of relaxation.
+ void
+ update_output_local_symbol_count();
+
+ // Whether we want to merge processor-specific flags and attributes.
+ bool
+ merge_flags_and_attributes() const
+ { return this->merge_flags_and_attributes_; }
+
+ // Export list of EXIDX section indices.
+ void
+ get_exidx_shndx_list(std::vector<unsigned int>* list) const
{
- typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
- Reltype addend = utils::sign_extend<16>(val);
- Reltype x = This::arm_symbol_value(object, psymval, addend, false);
- val = utils::bit_select(val, x, 0xffffU);
- elfcpp::Swap<16, big_endian>::writeval(wv, val);
- return (utils::has_signed_unsigned_overflow<16>(x)
- ? This::STATUS_OVERFLOW
- : This::STATUS_OKAY);
+ list->clear();
+ for (Exidx_section_map::const_iterator p = this->exidx_section_map_.begin();
+ p != this->exidx_section_map_.end();
+ ++p)
+ {
+ if (p->second->shndx() == p->first)
+ list->push_back(p->first);
+ }
+ // Sort list to make result independent of implementation of map.
+ std::sort(list->begin(), list->end());
}
- // R_ARM_ABS32: (S + A) | T
- static inline typename This::Status
- abs32(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- bool has_thumb_bit)
+ protected:
+ // Post constructor setup.
+ void
+ do_setup()
{
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
- Valtype x = This::arm_symbol_value(object, psymval, addend, has_thumb_bit);
- elfcpp::Swap<32, big_endian>::writeval(wv, x);
- return This::STATUS_OKAY;
+ // Call parent's setup method.
+ Sized_relobj<32, big_endian>::do_setup();
+
+ // Initialize look-up tables.
+ Stub_table_list empty_stub_table_list(this->shnum(), NULL);
+ this->stub_tables_.swap(empty_stub_table_list);
}
- // R_ARM_REL32: (S + A) | T - P
- static inline typename This::Status
- rel32(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address,
- bool has_thumb_bit)
- {
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
- Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
- - address);
- elfcpp::Swap<32, big_endian>::writeval(wv, x);
- return This::STATUS_OKAY;
- }
+ // Count the local symbols.
+ void
+ do_count_local_symbols(Stringpool_template<char>*,
+ Stringpool_template<char>*);
- // R_ARM_THM_CALL: (S + A) | T - P
- static inline typename This::Status
- thm_call(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address,
- bool has_thumb_bit)
- {
- // A thumb call consists of two instructions.
- typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype hi = elfcpp::Swap<16, big_endian>::readval(wv);
- Valtype lo = elfcpp::Swap<16, big_endian>::readval(wv + 1);
- // Must be a BL instruction. lo == 11111xxxxxxxxxxx.
- gold_assert((lo & 0xf800) == 0xf800);
- Reltype addend = utils::sign_extend<23>(((hi & 0x7ff) << 12)
- | ((lo & 0x7ff) << 1));
- Reltype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
- - address);
-
- // If target has no thumb bit set, we need to either turn the BL
- // into a BLX (for ARMv5 or above) or generate a stub.
- if ((x & 1) == 0)
- {
- // This only works for ARMv5 and above with interworking enabled.
- lo &= 0xefff;
- }
- hi = utils::bit_select(hi, (x >> 12), 0x7ffU);
- lo = utils::bit_select(lo, (x >> 1), 0x7ffU);
- elfcpp::Swap<16, big_endian>::writeval(wv, hi);
- elfcpp::Swap<16, big_endian>::writeval(wv + 1, lo);
- return (utils::has_overflow<23>(x)
- ? This::STATUS_OVERFLOW
- : This::STATUS_OKAY);
- }
+ void
+ do_relocate_sections(const Symbol_table* symtab, const Layout* layout,
+ const unsigned char* pshdrs,
+ typename Sized_relobj<32, big_endian>::Views* pivews);
- // R_ARM_BASE_PREL: B(S) + A - P
- static inline typename This::Status
- base_prel(unsigned char* view,
- elfcpp::Elf_types<32>::Elf_Addr origin,
- elfcpp::Elf_types<32>::Elf_Addr address)
- {
- Base::rel32(view, origin - address);
- return STATUS_OKAY;
- }
+ // Read the symbol information.
+ void
+ do_read_symbols(Read_symbols_data* sd);
- // R_ARM_BASE_ABS: B(S) + A
- static inline typename This::Status
- base_abs(unsigned char* view,
- elfcpp::Elf_types<32>::Elf_Addr origin)
- {
- Base::rel32(view, origin);
- return STATUS_OKAY;
- }
+ // Process relocs for garbage collection.
+ void
+ do_gc_process_relocs(Symbol_table*, Layout*, Read_relocs_data*);
- // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
- static inline typename This::Status
- got_brel(unsigned char* view,
- typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
- {
- Base::rel32(view, got_offset);
- return This::STATUS_OKAY;
- }
+ private:
- // R_ARM_GOT_PREL: GOT(S) + A – P
- static inline typename This::Status
- got_prel(unsigned char* view,
- typename elfcpp::Swap<32, big_endian>::Valtype got_offset,
- elfcpp::Elf_types<32>::Elf_Addr address)
- {
- Base::rel32(view, got_offset - address);
- return This::STATUS_OKAY;
- }
+ // Whether a section needs to be scanned for relocation stubs.
+ bool
+ section_needs_reloc_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
+ const Relobj::Output_sections&,
+ const Symbol_table *, const unsigned char*);
- // R_ARM_PLT32: (S + A) | T - P
- static inline typename This::Status
- plt32(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address,
- bool has_thumb_bit)
- {
- return arm_branch_common<elfcpp::R_ARM_PLT32>(view, object, psymval,
- address, has_thumb_bit);
- }
+ // Whether a section is a scannable text section.
+ bool
+ section_is_scannable(const elfcpp::Shdr<32, big_endian>&, unsigned int,
+ const Output_section*, const Symbol_table *);
- // R_ARM_CALL: (S + A) | T - P
- static inline typename This::Status
- call(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address,
- bool has_thumb_bit)
- {
- return arm_branch_common<elfcpp::R_ARM_CALL>(view, object, psymval,
- address, has_thumb_bit);
- }
+ // Whether a section needs to be scanned for the Cortex-A8 erratum.
+ bool
+ section_needs_cortex_a8_stub_scanning(const elfcpp::Shdr<32, big_endian>&,
+ unsigned int, Output_section*,
+ const Symbol_table *);
- // R_ARM_JUMP24: (S + A) | T - P
- static inline typename This::Status
- jump24(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address,
- bool has_thumb_bit)
- {
- return arm_branch_common<elfcpp::R_ARM_JUMP24>(view, object, psymval,
- address, has_thumb_bit);
- }
+ // Scan a section for the Cortex-A8 erratum.
+ void
+ scan_section_for_cortex_a8_erratum(const elfcpp::Shdr<32, big_endian>&,
+ unsigned int, Output_section*,
+ Target_arm<big_endian>*);
+
+ // Find the linked text section of an EXIDX section by looking at the
+ // first reloction of the EXIDX section. PSHDR points to the section
+ // headers of a relocation section and PSYMS points to the local symbols.
+ // PSHNDX points to a location storing the text section index if found.
+ // Return whether we can find the linked section.
+ bool
+ find_linked_text_section(const unsigned char* pshdr,
+ const unsigned char* psyms, unsigned int* pshndx);
- // R_ARM_PREL: (S + A) | T - P
- static inline typename This::Status
- prel31(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address,
- bool has_thumb_bit)
- {
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
- Valtype addend = utils::sign_extend<31>(val);
- Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
- - address);
- val = utils::bit_select(val, x, 0x7fffffffU);
- elfcpp::Swap<32, big_endian>::writeval(wv, val);
- return (utils::has_overflow<31>(x) ?
- This::STATUS_OVERFLOW : This::STATUS_OKAY);
- }
+ //
+ // Make a new Arm_exidx_input_section object for EXIDX section with
+ // index SHNDX and section header SHDR. TEXT_SHNDX is the section
+ // index of the linked text section.
+ void
+ make_exidx_input_section(unsigned int shndx,
+ const elfcpp::Shdr<32, big_endian>& shdr,
+ unsigned int text_shndx,
+ const elfcpp::Shdr<32, big_endian>& text_shdr);
- // R_ARM_MOVW_ABS_NC: (S + A) | T
- static inline typename This::Status
- movw_abs_nc(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- bool has_thumb_bit)
- {
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
- Valtype addend = This::extract_arm_movw_movt_addend(val);
- Valtype x = This::arm_symbol_value(object, psymval, addend, has_thumb_bit);
- val = This::insert_val_arm_movw_movt(val, x);
- elfcpp::Swap<32, big_endian>::writeval(wv, val);
- return This::STATUS_OKAY;
- }
+ // Return the output address of either a plain input section or a
+ // relaxed input section. SHNDX is the section index.
+ Arm_address
+ simple_input_section_output_address(unsigned int, Output_section*);
+
+ typedef std::vector<Stub_table<big_endian>*> Stub_table_list;
+ typedef Unordered_map<unsigned int, const Arm_exidx_input_section*>
+ Exidx_section_map;
+
+ // List of stub tables.
+ Stub_table_list stub_tables_;
+ // Bit vector to tell if a local symbol is a thumb function or not.
+ // This is only valid after do_count_local_symbol is called.
+ std::vector<bool> local_symbol_is_thumb_function_;
+ // processor-specific flags in ELF file header.
+ elfcpp::Elf_Word processor_specific_flags_;
+ // Object attributes if there is an .ARM.attributes section or NULL.
+ Attributes_section_data* attributes_section_data_;
+ // Mapping symbols information.
+ Mapping_symbols_info mapping_symbols_info_;
+ // Bitmap to indicate sections with Cortex-A8 workaround or NULL.
+ std::vector<bool>* section_has_cortex_a8_workaround_;
+ // Map a text section to its associated .ARM.exidx section, if there is one.
+ Exidx_section_map exidx_section_map_;
+ // Whether output local symbol count needs updating.
+ bool output_local_symbol_count_needs_update_;
+ // Whether we merge processor flags and attributes of this object to
+ // output.
+ bool merge_flags_and_attributes_;
+};
- // R_ARM_MOVT_ABS: S + A
- static inline typename This::Status
- movt_abs(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval)
- {
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
- Valtype addend = This::extract_arm_movw_movt_addend(val);
- Valtype x = This::arm_symbol_value(object, psymval, addend, 0) >> 16;
- val = This::insert_val_arm_movw_movt(val, x);
- elfcpp::Swap<32, big_endian>::writeval(wv, val);
- return This::STATUS_OKAY;
- }
+// Arm_dynobj class.
- // R_ARM_THM_MOVW_ABS_NC: S + A | T
- static inline typename This::Status
- thm_movw_abs_nc(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- bool has_thumb_bit)
- {
- typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16)
- | elfcpp::Swap<16, big_endian>::readval(wv + 1));
- Reltype addend = extract_thumb_movw_movt_addend(val);
- Reltype x = This::arm_symbol_value(object, psymval, addend, has_thumb_bit);
- val = This::insert_val_thumb_movw_movt(val, x);
- elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
- elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
- return This::STATUS_OKAY;
- }
+template<bool big_endian>
+class Arm_dynobj : public Sized_dynobj<32, big_endian>
+{
+ public:
+ Arm_dynobj(const std::string& name, Input_file* input_file, off_t offset,
+ const elfcpp::Ehdr<32, big_endian>& ehdr)
+ : Sized_dynobj<32, big_endian>(name, input_file, offset, ehdr),
+ processor_specific_flags_(0), attributes_section_data_(NULL)
+ { }
+
+ ~Arm_dynobj()
+ { delete this->attributes_section_data_; }
+
+ // Downcast a base pointer to an Arm_relobj pointer. This is
+ // not type-safe but we only use Arm_relobj not the base class.
+ static Arm_dynobj<big_endian>*
+ as_arm_dynobj(Dynobj* dynobj)
+ { return static_cast<Arm_dynobj<big_endian>*>(dynobj); }
+
+ // Processor-specific flags in ELF file header. This is valid only after
+ // reading symbols.
+ elfcpp::Elf_Word
+ processor_specific_flags() const
+ { return this->processor_specific_flags_; }
+
+ // Attributes section data.
+ const Attributes_section_data*
+ attributes_section_data() const
+ { return this->attributes_section_data_; }
- // R_ARM_THM_MOVT_ABS: S + A
- static inline typename This::Status
- thm_movt_abs(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval)
- {
- typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Reltype val = ((elfcpp::Swap<16, big_endian>::readval(wv) << 16)
- | elfcpp::Swap<16, big_endian>::readval(wv + 1));
- Reltype addend = This::extract_thumb_movw_movt_addend(val);
- Reltype x = This::arm_symbol_value(object, psymval, addend, 0) >> 16;
- val = This::insert_val_thumb_movw_movt(val, x);
- elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
- elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
- return This::STATUS_OKAY;
- }
+ protected:
+ // Read the symbol information.
+ void
+ do_read_symbols(Read_symbols_data* sd);
- // R_ARM_MOVW_PREL_NC: (S + A) | T - P
- static inline typename This::Status
- movw_prel_nc(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address,
- bool has_thumb_bit)
- {
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
- Valtype addend = This::extract_arm_movw_movt_addend(val);
- Valtype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
- - address);
- val = This::insert_val_arm_movw_movt(val, x);
- elfcpp::Swap<32, big_endian>::writeval(wv, val);
- return This::STATUS_OKAY;
- }
+ private:
+ // processor-specific flags in ELF file header.
+ elfcpp::Elf_Word processor_specific_flags_;
+ // Object attributes if there is an .ARM.attributes section or NULL.
+ Attributes_section_data* attributes_section_data_;
+};
- // R_ARM_MOVT_PREL: S + A - P
- static inline typename This::Status
- movt_prel(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address)
- {
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
- Valtype addend = This::extract_arm_movw_movt_addend(val);
- Valtype x = (This::arm_symbol_value(object, psymval, addend, 0)
- - address) >> 16;
- val = This::insert_val_arm_movw_movt(val, x);
- elfcpp::Swap<32, big_endian>::writeval(wv, val);
- return This::STATUS_OKAY;
- }
+// Functor to read reloc addends during stub generation.
- // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
- static inline typename This::Status
- thm_movw_prel_nc(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address,
- bool has_thumb_bit)
- {
- typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
- | elfcpp::Swap<16, big_endian>::readval(wv + 1);
- Reltype addend = This::extract_thumb_movw_movt_addend(val);
- Reltype x = (This::arm_symbol_value(object, psymval, addend, has_thumb_bit)
- - address);
- val = This::insert_val_thumb_movw_movt(val, x);
- elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
- elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
- return This::STATUS_OKAY;
- }
+template<int sh_type, bool big_endian>
+struct Stub_addend_reader
+{
+ // Return the addend for a relocation of a particular type. Depending
+ // on whether this is a REL or RELA relocation, read the addend from a
+ // view or from a Reloc object.
+ elfcpp::Elf_types<32>::Elf_Swxword
+ operator()(
+ unsigned int /* r_type */,
+ const unsigned char* /* view */,
+ const typename Reloc_types<sh_type,
+ 32, big_endian>::Reloc& /* reloc */) const;
+};
- // R_ARM_THM_MOVT_PREL: S + A - P
- static inline typename This::Status
- thm_movt_prel(unsigned char *view,
- const Sized_relobj<32, big_endian>* object,
- const Symbol_value<32>* psymval,
- elfcpp::Elf_types<32>::Elf_Addr address)
- {
- typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
- typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
- Valtype* wv = reinterpret_cast<Valtype*>(view);
- Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
- | elfcpp::Swap<16, big_endian>::readval(wv + 1);
- Reltype addend = This::extract_thumb_movw_movt_addend(val);
- Reltype x = (This::arm_symbol_value(object, psymval, addend, 0)
- - address) >> 16;
- val = This::insert_val_thumb_movw_movt(val, x);
- elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
- elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
- return This::STATUS_OKAY;
- }
+// Specialized Stub_addend_reader for SHT_REL type relocation sections.
+
+template<bool big_endian>
+struct Stub_addend_reader<elfcpp::SHT_REL, big_endian>
+{
+ elfcpp::Elf_types<32>::Elf_Swxword
+ operator()(
+ unsigned int,
+ const unsigned char*,
+ const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const;
};
-// Get the GOT section, creating it if necessary.
+// Specialized Stub_addend_reader for RELA type relocation sections.
+// We currently do not handle RELA type relocation sections but it is trivial
+// to implement the addend reader. This is provided for completeness and to
+// make it easier to add support for RELA relocation sections in the future.
template<bool big_endian>
-Output_data_got<32, big_endian>*
-Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
+struct Stub_addend_reader<elfcpp::SHT_RELA, big_endian>
{
- if (this->got_ == NULL)
- {
- gold_assert(symtab != NULL && layout != NULL);
+ elfcpp::Elf_types<32>::Elf_Swxword
+ operator()(
+ unsigned int,
+ const unsigned char*,
+ const typename Reloc_types<elfcpp::SHT_RELA, 32,
+ big_endian>::Reloc& reloc) const
+ { return reloc.get_r_addend(); }
+};
- this->got_ = new Output_data_got<32, big_endian>();
+// Cortex_a8_reloc class. We keep record of relocation that may need
+// the Cortex-A8 erratum workaround.
- Output_section* os;
- os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
- (elfcpp::SHF_ALLOC
- | elfcpp::SHF_WRITE),
- this->got_);
- os->set_is_relro();
+class Cortex_a8_reloc
+{
+ public:
+ Cortex_a8_reloc(Reloc_stub* reloc_stub, unsigned r_type,
+ Arm_address destination)
+ : reloc_stub_(reloc_stub), r_type_(r_type), destination_(destination)
+ { }
- // The old GNU linker creates a .got.plt section. We just
- // create another set of data in the .got section. Note that we
- // always create a PLT if we create a GOT, although the PLT
- // might be empty.
- this->got_plt_ = new Output_data_space(4, "** GOT PLT");
- os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
- (elfcpp::SHF_ALLOC
- | elfcpp::SHF_WRITE),
- this->got_plt_);
- os->set_is_relro();
+ ~Cortex_a8_reloc()
+ { }
- // The first three entries are reserved.
- this->got_plt_->set_current_data_size(3 * 4);
+ // Accessors: This is a read-only class.
+
+ // Return the relocation stub associated with this relocation if there is
+ // one.
+ const Reloc_stub*
+ reloc_stub() const
+ { return this->reloc_stub_; }
+
+ // Return the relocation type.
+ unsigned int
+ r_type() const
+ { return this->r_type_; }
- // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
- symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
- this->got_plt_,
- 0, 0, elfcpp::STT_OBJECT,
- elfcpp::STB_LOCAL,
- elfcpp::STV_HIDDEN, 0,
- false, false);
- }
- return this->got_;
-}
+ // Return the destination address of the relocation. LSB stores the THUMB
+ // bit.
+ Arm_address
+ destination() const
+ { return this->destination_; }
-// Get the dynamic reloc section, creating it if necessary.
+ private:
+ // Associated relocation stub if there is one, or NULL.
+ const Reloc_stub* reloc_stub_;
+ // Relocation type.
+ unsigned int r_type_;
+ // Destination address of this relocation. LSB is used to distinguish
+ // ARM/THUMB mode.
+ Arm_address destination_;
+};
+
+// Arm_output_data_got class. We derive this from Output_data_got to add
+// extra methods to handle TLS relocations in a static link.
template<bool big_endian>
-typename Target_arm<big_endian>::Reloc_section*
-Target_arm<big_endian>::rel_dyn_section(Layout* layout)
+class Arm_output_data_got : public Output_data_got<32, big_endian>
{
- if (this->rel_dyn_ == NULL)
- {
- gold_assert(layout != NULL);
- this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
- layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
- elfcpp::SHF_ALLOC, this->rel_dyn_);
- }
- return this->rel_dyn_;
-}
+ public:
+ Arm_output_data_got(Symbol_table* symtab, Layout* layout)
+ : Output_data_got<32, big_endian>(), symbol_table_(symtab), layout_(layout)
+ { }
-// Insn_template methods.
+ // Add a static entry for the GOT entry at OFFSET. GSYM is a global
+ // symbol and R_TYPE is the code of a dynamic relocation that needs to be
+ // applied in a static link.
+ void
+ add_static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
+ { this->static_relocs_.push_back(Static_reloc(got_offset, r_type, gsym)); }
-// Return byte size of an instruction template.
+ // Add a static reloc for the GOT entry at OFFSET. RELOBJ is an object
+ // defining a local symbol with INDEX. R_TYPE is the code of a dynamic
+ // relocation that needs to be applied in a static link.
+ void
+ add_static_reloc(unsigned int got_offset, unsigned int r_type,
+ Sized_relobj<32, big_endian>* relobj, unsigned int index)
+ {
+ this->static_relocs_.push_back(Static_reloc(got_offset, r_type, relobj,
+ index));
+ }
-size_t
-Insn_template::size() const
-{
- switch (this->type())
- {
- case THUMB16_TYPE:
- return 2;
- case ARM_TYPE:
- case THUMB32_TYPE:
- case DATA_TYPE:
- return 4;
- default:
- gold_unreachable();
- }
-}
-
-// Return alignment of an instruction template.
+ // Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
+ // The first one is initialized to be 1, which is the module index for
+ // the main executable and the second one 0. A reloc of the type
+ // R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
+ // be applied by gold. GSYM is a global symbol.
+ void
+ add_tls_gd32_with_static_reloc(unsigned int got_type, Symbol* gsym);
-unsigned
-Insn_template::alignment() const
-{
- switch (this->type())
- {
- case THUMB16_TYPE:
- case THUMB32_TYPE:
- return 2;
- case ARM_TYPE:
- case DATA_TYPE:
- return 4;
- default:
- gold_unreachable();
- }
-}
+ // Same as the above but for a local symbol in OBJECT with INDEX.
+ void
+ add_tls_gd32_with_static_reloc(unsigned int got_type,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int index);
-// Stub_template methods.
+ protected:
+ // Write out the GOT table.
+ void
+ do_write(Output_file*);
-Stub_template::Stub_template(
- Stub_type type, const Insn_template* insns,
- size_t insn_count)
- : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
- entry_in_thumb_mode_(false), relocs_()
-{
- off_t offset = 0;
+ private:
+ // This class represent dynamic relocations that need to be applied by
+ // gold because we are using TLS relocations in a static link.
+ class Static_reloc
+ {
+ public:
+ Static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
+ : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(true)
+ { this->u_.global.symbol = gsym; }
- // Compute byte size and alignment of stub template.
- for (size_t i = 0; i < insn_count; i++)
+ Static_reloc(unsigned int got_offset, unsigned int r_type,
+ Sized_relobj<32, big_endian>* relobj, unsigned int index)
+ : got_offset_(got_offset), r_type_(r_type), symbol_is_global_(false)
{
- unsigned insn_alignment = insns[i].alignment();
- size_t insn_size = insns[i].size();
- gold_assert((offset & (insn_alignment - 1)) == 0);
- this->alignment_ = std::max(this->alignment_, insn_alignment);
- switch (insns[i].type())
- {
- case Insn_template::THUMB16_TYPE:
- if (i == 0)
- this->entry_in_thumb_mode_ = true;
- break;
-
- case Insn_template::THUMB32_TYPE:
- if (insns[i].r_type() != elfcpp::R_ARM_NONE)
- this->relocs_.push_back(Reloc(i, offset));
- if (i == 0)
- this->entry_in_thumb_mode_ = true;
- break;
-
- case Insn_template::ARM_TYPE:
- // Handle cases where the target is encoded within the
- // instruction.
- if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
- this->relocs_.push_back(Reloc(i, offset));
- break;
-
- case Insn_template::DATA_TYPE:
- // Entry point cannot be data.
- gold_assert(i != 0);
- this->relocs_.push_back(Reloc(i, offset));
- break;
-
- default:
- gold_unreachable();
- }
- offset += insn_size;
+ this->u_.local.relobj = relobj;
+ this->u_.local.index = index;
}
- this->size_ = offset;
-}
-// Reloc_stub::Key methods.
+ // Return the GOT offset.
+ unsigned int
+ got_offset() const
+ { return this->got_offset_; }
-// Dump a Key as a string for debugging.
+ // Relocation type.
+ unsigned int
+ r_type() const
+ { return this->r_type_; }
-std::string
-Reloc_stub::Key::name() const
-{
- if (this->r_sym_ == invalid_index)
- {
- // Global symbol key name
- // <stub-type>:<symbol name>:<addend>.
- const std::string sym_name = this->u_.symbol->name();
- // We need to print two hex number and two colons. So just add 100 bytes
- // to the symbol name size.
- size_t len = sym_name.size() + 100;
- char* buffer = new char[len];
- int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
- sym_name.c_str(), this->addend_);
- gold_assert(c > 0 && c < static_cast<int>(len));
- delete[] buffer;
- return std::string(buffer);
- }
- else
+ // Whether the symbol is global or not.
+ bool
+ symbol_is_global() const
+ { return this->symbol_is_global_; }
+
+ // For a relocation against a global symbol, the global symbol.
+ Symbol*
+ symbol() const
{
- // local symbol key name
- // <stub-type>:<object>:<r_sym>:<addend>.
- const size_t len = 200;
- char buffer[len];
- int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
- this->u_.relobj, this->r_sym_, this->addend_);
- gold_assert(c > 0 && c < static_cast<int>(len));
- return std::string(buffer);
+ gold_assert(this->symbol_is_global_);
+ return this->u_.global.symbol;
}
-}
-
-// Reloc_stub methods.
-
-// Determine the type of stub needed, if any, for a relocation of R_TYPE at
-// LOCATION to DESTINATION.
-// This code is based on the arm_type_of_stub function in
-// bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
-// class simple.
-
-Stub_type
-Reloc_stub::stub_type_for_reloc(
- unsigned int r_type,
- Arm_address location,
- Arm_address destination,
- bool target_is_thumb)
-{
- Stub_type stub_type = arm_stub_none;
- // This is a bit ugly but we want to avoid using a templated class for
- // big and little endianities.
- bool may_use_blx;
- bool should_force_pic_veneer;
- bool thumb2;
- bool thumb_only;
- if (parameters->target().is_big_endian())
+ // For a relocation against a local symbol, the defining object.
+ Sized_relobj<32, big_endian>*
+ relobj() const
{
- const Target_arm<true>& big_endian_target =
- Target_arm<true>::default_target();
- may_use_blx = big_endian_target.may_use_blx();
- should_force_pic_veneer = big_endian_target.should_force_pic_veneer();
- thumb2 = big_endian_target.using_thumb2();
- thumb_only = big_endian_target.using_thumb_only();
+ gold_assert(!this->symbol_is_global_);
+ return this->u_.local.relobj;
}
- else
+
+ // For a relocation against a local symbol, the local symbol index.
+ unsigned int
+ index() const
{
- const Target_arm<false>& little_endian_target =
- Target_arm<false>::default_target();
- may_use_blx = little_endian_target.may_use_blx();
- should_force_pic_veneer = little_endian_target.should_force_pic_veneer();
- thumb2 = little_endian_target.using_thumb2();
- thumb_only = little_endian_target.using_thumb_only();
+ gold_assert(!this->symbol_is_global_);
+ return this->u_.local.index;
}
- int64_t branch_offset = (int64_t)destination - location;
-
- if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
+ private:
+ // GOT offset of the entry to which this relocation is applied.
+ unsigned int got_offset_;
+ // Type of relocation.
+ unsigned int r_type_;
+ // Whether this relocation is against a global symbol.
+ bool symbol_is_global_;
+ // A global or local symbol.
+ union
{
- // Handle cases where:
- // - this call goes too far (different Thumb/Thumb2 max
- // distance)
- // - it's a Thumb->Arm call and blx is not available, or it's a
- // Thumb->Arm branch (not bl). A stub is needed in this case.
- if ((!thumb2
- && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
- || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
- || (thumb2
- && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
- || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
- || ((!target_is_thumb)
- && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
- || (r_type == elfcpp::R_ARM_THM_JUMP24))))
- {
- if (target_is_thumb)
- {
- // Thumb to thumb.
- if (!thumb_only)
- {
- stub_type = (parameters->options().shared() | should_force_pic_veneer)
- // PIC stubs.
- ? ((may_use_blx
- && (r_type == elfcpp::R_ARM_THM_CALL))
- // V5T and above. Stub starts with ARM code, so
- // we must be able to switch mode before
- // reaching it, which is only possible for 'bl'
- // (ie R_ARM_THM_CALL relocation).
- ? arm_stub_long_branch_any_thumb_pic
- // On V4T, use Thumb code only.
- : arm_stub_long_branch_v4t_thumb_thumb_pic)
+ struct
+ {
+ // For a global symbol, the symbol itself.
+ Symbol* symbol;
+ } global;
+ struct
+ {
+ // For a local symbol, the object defining object.
+ Sized_relobj<32, big_endian>* relobj;
+ // For a local symbol, the symbol index.
+ unsigned int index;
+ } local;
+ } u_;
+ };
- // non-PIC stubs.
- : ((may_use_blx
- && (r_type == elfcpp::R_ARM_THM_CALL))
- ? arm_stub_long_branch_any_any // V5T and above.
- : arm_stub_long_branch_v4t_thumb_thumb); // V4T.
- }
- else
- {
- stub_type = (parameters->options().shared() | should_force_pic_veneer)
- ? arm_stub_long_branch_thumb_only_pic // PIC stub.
- : arm_stub_long_branch_thumb_only; // non-PIC stub.
- }
- }
- else
- {
- // Thumb to arm.
-
- // FIXME: We should check that the input section is from an
- // object that has interwork enabled.
+ // Symbol table of the output object.
+ Symbol_table* symbol_table_;
+ // Layout of the output object.
+ Layout* layout_;
+ // Static relocs to be applied to the GOT.
+ std::vector<Static_reloc> static_relocs_;
+};
- stub_type = (parameters->options().shared()
- || should_force_pic_veneer)
- // PIC stubs.
- ? ((may_use_blx
- && (r_type == elfcpp::R_ARM_THM_CALL))
- ? arm_stub_long_branch_any_arm_pic // V5T and above.
- : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
+// The ARM target has many relocation types with odd-sizes or incontigious
+// bits. The default handling of relocatable relocation cannot process these
+// relocations. So we have to extend the default code.
- // non-PIC stubs.
- : ((may_use_blx
- && (r_type == elfcpp::R_ARM_THM_CALL))
- ? arm_stub_long_branch_any_any // V5T and above.
- : arm_stub_long_branch_v4t_thumb_arm); // V4T.
+template<bool big_endian, int sh_type, typename Classify_reloc>
+class Arm_scan_relocatable_relocs :
+ public Default_scan_relocatable_relocs<sh_type, Classify_reloc>
+{
+ public:
+ // Return the strategy to use for a local symbol which is a section
+ // symbol, given the relocation type.
+ inline Relocatable_relocs::Reloc_strategy
+ local_section_strategy(unsigned int r_type, Relobj*)
+ {
+ if (sh_type == elfcpp::SHT_RELA)
+ return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
+ else
+ {
+ if (r_type == elfcpp::R_ARM_TARGET1
+ || r_type == elfcpp::R_ARM_TARGET2)
+ {
+ const Target_arm<big_endian>* arm_target =
+ Target_arm<big_endian>::default_target();
+ r_type = arm_target->get_real_reloc_type(r_type);
+ }
- // Handle v4t short branches.
- if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
- && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
- && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
- stub_type = arm_stub_short_branch_v4t_thumb_arm;
- }
- }
- }
- else if (r_type == elfcpp::R_ARM_CALL
- || r_type == elfcpp::R_ARM_JUMP24
- || r_type == elfcpp::R_ARM_PLT32)
- {
- if (target_is_thumb)
- {
- // Arm to thumb.
+ switch(r_type)
+ {
+ // Relocations that write nothing. These exclude R_ARM_TARGET1
+ // and R_ARM_TARGET2.
+ case elfcpp::R_ARM_NONE:
+ case elfcpp::R_ARM_V4BX:
+ case elfcpp::R_ARM_TLS_GOTDESC:
+ case elfcpp::R_ARM_TLS_CALL:
+ case elfcpp::R_ARM_TLS_DESCSEQ:
+ case elfcpp::R_ARM_THM_TLS_CALL:
+ case elfcpp::R_ARM_GOTRELAX:
+ case elfcpp::R_ARM_GNU_VTENTRY:
+ case elfcpp::R_ARM_GNU_VTINHERIT:
+ case elfcpp::R_ARM_THM_TLS_DESCSEQ16:
+ case elfcpp::R_ARM_THM_TLS_DESCSEQ32:
+ return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
+ // These should have been converted to something else above.
+ case elfcpp::R_ARM_TARGET1:
+ case elfcpp::R_ARM_TARGET2:
+ gold_unreachable();
+ // Relocations that write full 32 bits.
+ case elfcpp::R_ARM_ABS32:
+ case elfcpp::R_ARM_REL32:
+ case elfcpp::R_ARM_SBREL32:
+ case elfcpp::R_ARM_GOTOFF32:
+ case elfcpp::R_ARM_BASE_PREL:
+ case elfcpp::R_ARM_GOT_BREL:
+ case elfcpp::R_ARM_BASE_ABS:
+ case elfcpp::R_ARM_ABS32_NOI:
+ case elfcpp::R_ARM_REL32_NOI:
+ case elfcpp::R_ARM_PLT32_ABS:
+ case elfcpp::R_ARM_GOT_ABS:
+ case elfcpp::R_ARM_GOT_PREL:
+ case elfcpp::R_ARM_TLS_GD32:
+ case elfcpp::R_ARM_TLS_LDM32:
+ case elfcpp::R_ARM_TLS_LDO32:
+ case elfcpp::R_ARM_TLS_IE32:
+ case elfcpp::R_ARM_TLS_LE32:
+ return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4;
+ default:
+ // For all other static relocations, return RELOC_SPECIAL.
+ return Relocatable_relocs::RELOC_SPECIAL;
+ }
+ }
+ }
+};
- // FIXME: We should check that the input section is from an
- // object that has interwork enabled.
+// Utilities for manipulating integers of up to 32-bits
- // We have an extra 2-bytes reach because of
- // the mode change (bit 24 (H) of BLX encoding).
- if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
- || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
- || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
- || (r_type == elfcpp::R_ARM_JUMP24)
- || (r_type == elfcpp::R_ARM_PLT32))
- {
+namespace utils
+{
+ // Sign extend an n-bit unsigned integer stored in an uint32_t into
+ // an int32_t. NO_BITS must be between 1 to 32.
+ template<int no_bits>
+ static inline int32_t
+ sign_extend(uint32_t bits)
+ {
+ gold_assert(no_bits >= 0 && no_bits <= 32);
+ if (no_bits == 32)
+ return static_cast<int32_t>(bits);
+ uint32_t mask = (~((uint32_t) 0)) >> (32 - no_bits);
+ bits &= mask;
+ uint32_t top_bit = 1U << (no_bits - 1);
+ int32_t as_signed = static_cast<int32_t>(bits);
+ return (bits & top_bit) ? as_signed + (-top_bit * 2) : as_signed;
+ }
+
+ // Detects overflow of an NO_BITS integer stored in a uint32_t.
+ template<int no_bits>
+ static inline bool
+ has_overflow(uint32_t bits)
+ {
+ gold_assert(no_bits >= 0 && no_bits <= 32);
+ if (no_bits == 32)
+ return false;
+ int32_t max = (1 << (no_bits - 1)) - 1;
+ int32_t min = -(1 << (no_bits - 1));
+ int32_t as_signed = static_cast<int32_t>(bits);
+ return as_signed > max || as_signed < min;
+ }
+
+ // Detects overflow of an NO_BITS integer stored in a uint32_t when it
+ // fits in the given number of bits as either a signed or unsigned value.
+ // For example, has_signed_unsigned_overflow<8> would check
+ // -128 <= bits <= 255
+ template<int no_bits>
+ static inline bool
+ has_signed_unsigned_overflow(uint32_t bits)
+ {
+ gold_assert(no_bits >= 2 && no_bits <= 32);
+ if (no_bits == 32)
+ return false;
+ int32_t max = static_cast<int32_t>((1U << no_bits) - 1);
+ int32_t min = -(1 << (no_bits - 1));
+ int32_t as_signed = static_cast<int32_t>(bits);
+ return as_signed > max || as_signed < min;
+ }
+
+ // Select bits from A and B using bits in MASK. For each n in [0..31],
+ // the n-th bit in the result is chosen from the n-th bits of A and B.
+ // A zero selects A and a one selects B.
+ static inline uint32_t
+ bit_select(uint32_t a, uint32_t b, uint32_t mask)
+ { return (a & ~mask) | (b & mask); }
+};
+
+template<bool big_endian>
+class Target_arm : public Sized_target<32, big_endian>
+{
+ public:
+ typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
+ Reloc_section;
+
+ // When were are relocating a stub, we pass this as the relocation number.
+ static const size_t fake_relnum_for_stubs = static_cast<size_t>(-1);
+
+ Target_arm()
+ : Sized_target<32, big_endian>(&arm_info),
+ got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
+ copy_relocs_(elfcpp::R_ARM_COPY), dynbss_(NULL),
+ got_mod_index_offset_(-1U), tls_base_symbol_defined_(false),
+ stub_tables_(), stub_factory_(Stub_factory::get_instance()),
+ may_use_blx_(false), should_force_pic_veneer_(false),
+ arm_input_section_map_(), attributes_section_data_(NULL),
+ fix_cortex_a8_(false), cortex_a8_relocs_info_()
+ { }
+
+ // Virtual function which is set to return true by a target if
+ // it can use relocation types to determine if a function's
+ // pointer is taken.
+ virtual bool
+ can_check_for_function_pointers() const
+ { return true; }
+
+ // Whether a section called SECTION_NAME may have function pointers to
+ // sections not eligible for safe ICF folding.
+ virtual bool
+ section_may_have_icf_unsafe_pointers(const char* section_name) const
+ {
+ return (!is_prefix_of(".ARM.exidx", section_name)
+ && !is_prefix_of(".ARM.extab", section_name)
+ && Target::section_may_have_icf_unsafe_pointers(section_name));
+ }
+
+ // Whether we can use BLX.
+ bool
+ may_use_blx() const
+ { return this->may_use_blx_; }
+
+ // Set use-BLX flag.
+ void
+ set_may_use_blx(bool value)
+ { this->may_use_blx_ = value; }
+
+ // Whether we force PCI branch veneers.
+ bool
+ should_force_pic_veneer() const
+ { return this->should_force_pic_veneer_; }
+
+ // Set PIC veneer flag.
+ void
+ set_should_force_pic_veneer(bool value)
+ { this->should_force_pic_veneer_ = value; }
+
+ // Whether we use THUMB-2 instructions.
+ bool
+ using_thumb2() const
+ {
+ Object_attribute* attr =
+ this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
+ int arch = attr->int_value();
+ return arch == elfcpp::TAG_CPU_ARCH_V6T2 || arch >= elfcpp::TAG_CPU_ARCH_V7;
+ }
+
+ // Whether we use THUMB/THUMB-2 instructions only.
+ bool
+ using_thumb_only() const
+ {
+ Object_attribute* attr =
+ this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
+
+ if (attr->int_value() == elfcpp::TAG_CPU_ARCH_V6_M
+ || attr->int_value() == elfcpp::TAG_CPU_ARCH_V6S_M)
+ return true;
+ if (attr->int_value() != elfcpp::TAG_CPU_ARCH_V7
+ && attr->int_value() != elfcpp::TAG_CPU_ARCH_V7E_M)
+ return false;
+ attr = this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
+ return attr->int_value() == 'M';
+ }
+
+ // Whether we have an NOP instruction. If not, use mov r0, r0 instead.
+ bool
+ may_use_arm_nop() const
+ {
+ Object_attribute* attr =
+ this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
+ int arch = attr->int_value();
+ return (arch == elfcpp::TAG_CPU_ARCH_V6T2
+ || arch == elfcpp::TAG_CPU_ARCH_V6K
+ || arch == elfcpp::TAG_CPU_ARCH_V7
+ || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
+ }
+
+ // Whether we have THUMB-2 NOP.W instruction.
+ bool
+ may_use_thumb2_nop() const
+ {
+ Object_attribute* attr =
+ this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
+ int arch = attr->int_value();
+ return (arch == elfcpp::TAG_CPU_ARCH_V6T2
+ || arch == elfcpp::TAG_CPU_ARCH_V7
+ || arch == elfcpp::TAG_CPU_ARCH_V7E_M);
+ }
+
+ // Process the relocations to determine unreferenced sections for
+ // garbage collection.
+ void
+ gc_process_relocs(Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ size_t local_symbol_count,
+ const unsigned char* plocal_symbols);
+
+ // Scan the relocations to look for symbol adjustments.
+ void
+ scan_relocs(Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ size_t local_symbol_count,
+ const unsigned char* plocal_symbols);
+
+ // Finalize the sections.
+ void
+ do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
+
+ // Return the value to use for a dynamic symbol which requires special
+ // treatment.
+ uint64_t
+ do_dynsym_value(const Symbol*) const;
+
+ // Relocate a section.
+ void
+ relocate_section(const Relocate_info<32, big_endian>*,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ unsigned char* view,
+ Arm_address view_address,
+ section_size_type view_size,
+ const Reloc_symbol_changes*);
+
+ // Scan the relocs during a relocatable link.
+ void
+ scan_relocatable_relocs(Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ size_t local_symbol_count,
+ const unsigned char* plocal_symbols,
+ Relocatable_relocs*);
+
+ // Relocate a section during a relocatable link.
+ void
+ relocate_for_relocatable(const Relocate_info<32, big_endian>*,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ off_t offset_in_output_section,
+ const Relocatable_relocs*,
+ unsigned char* view,
+ Arm_address view_address,
+ section_size_type view_size,
+ unsigned char* reloc_view,
+ section_size_type reloc_view_size);
+
+ // Perform target-specific processing in a relocatable link. This is
+ // only used if we use the relocation strategy RELOC_SPECIAL.
+ void
+ relocate_special_relocatable(const Relocate_info<32, big_endian>* relinfo,
+ unsigned int sh_type,
+ const unsigned char* preloc_in,
+ size_t relnum,
+ Output_section* output_section,
+ off_t offset_in_output_section,
+ unsigned char* view,
+ typename elfcpp::Elf_types<32>::Elf_Addr
+ view_address,
+ section_size_type view_size,
+ unsigned char* preloc_out);
+
+ // Return whether SYM is defined by the ABI.
+ bool
+ do_is_defined_by_abi(Symbol* sym) const
+ { return strcmp(sym->name(), "__tls_get_addr") == 0; }
+
+ // Return whether there is a GOT section.
+ bool
+ has_got_section() const
+ { return this->got_ != NULL; }
+
+ // Return the size of the GOT section.
+ section_size_type
+ got_size()
+ {
+ gold_assert(this->got_ != NULL);
+ return this->got_->data_size();
+ }
+
+ // Map platform-specific reloc types
+ static unsigned int
+ get_real_reloc_type (unsigned int r_type);
+
+ //
+ // Methods to support stub-generations.
+ //
+
+ // Return the stub factory
+ const Stub_factory&
+ stub_factory() const
+ { return this->stub_factory_; }
+
+ // Make a new Arm_input_section object.
+ Arm_input_section<big_endian>*
+ new_arm_input_section(Relobj*, unsigned int);
+
+ // Find the Arm_input_section object corresponding to the SHNDX-th input
+ // section of RELOBJ.
+ Arm_input_section<big_endian>*
+ find_arm_input_section(Relobj* relobj, unsigned int shndx) const;
+
+ // Make a new Stub_table
+ Stub_table<big_endian>*
+ new_stub_table(Arm_input_section<big_endian>*);
+
+ // Scan a section for stub generation.
+ void
+ scan_section_for_stubs(const Relocate_info<32, big_endian>*, unsigned int,
+ const unsigned char*, size_t, Output_section*,
+ bool, const unsigned char*, Arm_address,
+ section_size_type);
+
+ // Relocate a stub.
+ void
+ relocate_stub(Stub*, const Relocate_info<32, big_endian>*,
+ Output_section*, unsigned char*, Arm_address,
+ section_size_type);
+
+ // Get the default ARM target.
+ static Target_arm<big_endian>*
+ default_target()
+ {
+ gold_assert(parameters->target().machine_code() == elfcpp::EM_ARM
+ && parameters->target().is_big_endian() == big_endian);
+ return static_cast<Target_arm<big_endian>*>(
+ parameters->sized_target<32, big_endian>());
+ }
+
+ // Whether NAME belongs to a mapping symbol.
+ static bool
+ is_mapping_symbol_name(const char* name)
+ {
+ return (name
+ && name[0] == '$'
+ && (name[1] == 'a' || name[1] == 't' || name[1] == 'd')
+ && (name[2] == '\0' || name[2] == '.'));
+ }
+
+ // Whether we work around the Cortex-A8 erratum.
+ bool
+ fix_cortex_a8() const
+ { return this->fix_cortex_a8_; }
+
+ // Whether we merge exidx entries in debuginfo.
+ bool
+ merge_exidx_entries() const
+ { return parameters->options().merge_exidx_entries(); }
+
+ // Whether we fix R_ARM_V4BX relocation.
+ // 0 - do not fix
+ // 1 - replace with MOV instruction (armv4 target)
+ // 2 - make interworking veneer (>= armv4t targets only)
+ General_options::Fix_v4bx
+ fix_v4bx() const
+ { return parameters->options().fix_v4bx(); }
+
+ // Scan a span of THUMB code section for Cortex-A8 erratum.
+ void
+ scan_span_for_cortex_a8_erratum(Arm_relobj<big_endian>*, unsigned int,
+ section_size_type, section_size_type,
+ const unsigned char*, Arm_address);
+
+ // Apply Cortex-A8 workaround to a branch.
+ void
+ apply_cortex_a8_workaround(const Cortex_a8_stub*, Arm_address,
+ unsigned char*, Arm_address);
+
+ protected:
+ // Make an ELF object.
+ Object*
+ do_make_elf_object(const std::string&, Input_file*, off_t,
+ const elfcpp::Ehdr<32, big_endian>& ehdr);
+
+ Object*
+ do_make_elf_object(const std::string&, Input_file*, off_t,
+ const elfcpp::Ehdr<32, !big_endian>&)
+ { gold_unreachable(); }
+
+ Object*
+ do_make_elf_object(const std::string&, Input_file*, off_t,
+ const elfcpp::Ehdr<64, false>&)
+ { gold_unreachable(); }
+
+ Object*
+ do_make_elf_object(const std::string&, Input_file*, off_t,
+ const elfcpp::Ehdr<64, true>&)
+ { gold_unreachable(); }
+
+ // Make an output section.
+ Output_section*
+ do_make_output_section(const char* name, elfcpp::Elf_Word type,
+ elfcpp::Elf_Xword flags)
+ { return new Arm_output_section<big_endian>(name, type, flags); }
+
+ void
+ do_adjust_elf_header(unsigned char* view, int len) const;
+
+ // We only need to generate stubs, and hence perform relaxation if we are
+ // not doing relocatable linking.
+ bool
+ do_may_relax() const
+ { return !parameters->options().relocatable(); }
+
+ bool
+ do_relax(int, const Input_objects*, Symbol_table*, Layout*);
+
+ // Determine whether an object attribute tag takes an integer, a
+ // string or both.
+ int
+ do_attribute_arg_type(int tag) const;
+
+ // Reorder tags during output.
+ int
+ do_attributes_order(int num) const;
+
+ // This is called when the target is selected as the default.
+ void
+ do_select_as_default_target()
+ {
+ // No locking is required since there should only be one default target.
+ // We cannot have both the big-endian and little-endian ARM targets
+ // as the default.
+ gold_assert(arm_reloc_property_table == NULL);
+ arm_reloc_property_table = new Arm_reloc_property_table();
+ }
+
+ private:
+ // The class which scans relocations.
+ class Scan
+ {
+ public:
+ Scan()
+ : issued_non_pic_error_(false)
+ { }
+
+ inline void
+ local(Symbol_table* symtab, Layout* layout, Target_arm* target,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ Output_section* output_section,
+ const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
+ const elfcpp::Sym<32, big_endian>& lsym);
+
+ inline void
+ global(Symbol_table* symtab, Layout* layout, Target_arm* target,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ Output_section* output_section,
+ const elfcpp::Rel<32, big_endian>& reloc, unsigned int r_type,
+ Symbol* gsym);
+
+ inline bool
+ local_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
+ Sized_relobj<32, big_endian>* ,
+ unsigned int ,
+ Output_section* ,
+ const elfcpp::Rel<32, big_endian>& ,
+ unsigned int ,
+ const elfcpp::Sym<32, big_endian>&);
+
+ inline bool
+ global_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_arm* ,
+ Sized_relobj<32, big_endian>* ,
+ unsigned int ,
+ Output_section* ,
+ const elfcpp::Rel<32, big_endian>& ,
+ unsigned int , Symbol*);
+
+ private:
+ static void
+ unsupported_reloc_local(Sized_relobj<32, big_endian>*,
+ unsigned int r_type);
+
+ static void
+ unsupported_reloc_global(Sized_relobj<32, big_endian>*,
+ unsigned int r_type, Symbol*);
+
+ void
+ check_non_pic(Relobj*, unsigned int r_type);
+
+ // Almost identical to Symbol::needs_plt_entry except that it also
+ // handles STT_ARM_TFUNC.
+ static bool
+ symbol_needs_plt_entry(const Symbol* sym)
+ {
+ // An undefined symbol from an executable does not need a PLT entry.
+ if (sym->is_undefined() && !parameters->options().shared())
+ return false;
+
+ return (!parameters->doing_static_link()
+ && (sym->type() == elfcpp::STT_FUNC
+ || sym->type() == elfcpp::STT_ARM_TFUNC)
+ && (sym->is_from_dynobj()
+ || sym->is_undefined()
+ || sym->is_preemptible()));
+ }
+
+ inline bool
+ possible_function_pointer_reloc(unsigned int r_type);
+
+ // Whether we have issued an error about a non-PIC compilation.
+ bool issued_non_pic_error_;
+ };
+
+ // The class which implements relocation.
+ class Relocate
+ {
+ public:
+ Relocate()
+ { }
+
+ ~Relocate()
+ { }
+
+ // Return whether the static relocation needs to be applied.
+ inline bool
+ should_apply_static_reloc(const Sized_symbol<32>* gsym,
+ int ref_flags,
+ bool is_32bit,
+ Output_section* output_section);
+
+ // Do a relocation. Return false if the caller should not issue
+ // any warnings about this relocation.
+ inline bool
+ relocate(const Relocate_info<32, big_endian>*, Target_arm*,
+ Output_section*, size_t relnum,
+ const elfcpp::Rel<32, big_endian>&,
+ unsigned int r_type, const Sized_symbol<32>*,
+ const Symbol_value<32>*,
+ unsigned char*, Arm_address,
+ section_size_type);
+
+ // Return whether we want to pass flag NON_PIC_REF for this
+ // reloc. This means the relocation type accesses a symbol not via
+ // GOT or PLT.
+ static inline bool
+ reloc_is_non_pic (unsigned int r_type)
+ {
+ switch (r_type)
+ {
+ // These relocation types reference GOT or PLT entries explicitly.
+ case elfcpp::R_ARM_GOT_BREL:
+ case elfcpp::R_ARM_GOT_ABS:
+ case elfcpp::R_ARM_GOT_PREL:
+ case elfcpp::R_ARM_GOT_BREL12:
+ case elfcpp::R_ARM_PLT32_ABS:
+ case elfcpp::R_ARM_TLS_GD32:
+ case elfcpp::R_ARM_TLS_LDM32:
+ case elfcpp::R_ARM_TLS_IE32:
+ case elfcpp::R_ARM_TLS_IE12GP:
+
+ // These relocate types may use PLT entries.
+ case elfcpp::R_ARM_CALL:
+ case elfcpp::R_ARM_THM_CALL:
+ case elfcpp::R_ARM_JUMP24:
+ case elfcpp::R_ARM_THM_JUMP24:
+ case elfcpp::R_ARM_THM_JUMP19:
+ case elfcpp::R_ARM_PLT32:
+ case elfcpp::R_ARM_THM_XPC22:
+ case elfcpp::R_ARM_PREL31:
+ case elfcpp::R_ARM_SBREL31:
+ return false;
+
+ default:
+ return true;
+ }
+ }
+
+ private:
+ // Do a TLS relocation.
+ inline typename Arm_relocate_functions<big_endian>::Status
+ relocate_tls(const Relocate_info<32, big_endian>*, Target_arm<big_endian>*,
+ size_t, const elfcpp::Rel<32, big_endian>&, unsigned int,
+ const Sized_symbol<32>*, const Symbol_value<32>*,
+ unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
+ section_size_type);
+
+ };
+
+ // A class which returns the size required for a relocation type,
+ // used while scanning relocs during a relocatable link.
+ class Relocatable_size_for_reloc
+ {
+ public:
+ unsigned int
+ get_size_for_reloc(unsigned int, Relobj*);
+ };
+
+ // Adjust TLS relocation type based on the options and whether this
+ // is a local symbol.
+ static tls::Tls_optimization
+ optimize_tls_reloc(bool is_final, int r_type);
+
+ // Get the GOT section, creating it if necessary.
+ Arm_output_data_got<big_endian>*
+ got_section(Symbol_table*, Layout*);
+
+ // Get the GOT PLT section.
+ Output_data_space*
+ got_plt_section() const
+ {
+ gold_assert(this->got_plt_ != NULL);
+ return this->got_plt_;
+ }
+
+ // Create a PLT entry for a global symbol.
+ void
+ make_plt_entry(Symbol_table*, Layout*, Symbol*);
+
+ // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
+ void
+ define_tls_base_symbol(Symbol_table*, Layout*);
+
+ // Create a GOT entry for the TLS module index.
+ unsigned int
+ got_mod_index_entry(Symbol_table* symtab, Layout* layout,
+ Sized_relobj<32, big_endian>* object);
+
+ // Get the PLT section.
+ const Output_data_plt_arm<big_endian>*
+ plt_section() const
+ {
+ gold_assert(this->plt_ != NULL);
+ return this->plt_;
+ }
+
+ // Get the dynamic reloc section, creating it if necessary.
+ Reloc_section*
+ rel_dyn_section(Layout*);
+
+ // Get the section to use for TLS_DESC relocations.
+ Reloc_section*
+ rel_tls_desc_section(Layout*) const;
+
+ // Return true if the symbol may need a COPY relocation.
+ // References from an executable object to non-function symbols
+ // defined in a dynamic object may need a COPY relocation.
+ bool
+ may_need_copy_reloc(Symbol* gsym)
+ {
+ return (gsym->type() != elfcpp::STT_ARM_TFUNC
+ && gsym->may_need_copy_reloc());
+ }
+
+ // Add a potential copy relocation.
+ void
+ copy_reloc(Symbol_table* symtab, Layout* layout,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int shndx, Output_section* output_section,
+ Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
+ {
+ this->copy_relocs_.copy_reloc(symtab, layout,
+ symtab->get_sized_symbol<32>(sym),
+ object, shndx, output_section, reloc,
+ this->rel_dyn_section(layout));
+ }
+
+ // Whether two EABI versions are compatible.
+ static bool
+ are_eabi_versions_compatible(elfcpp::Elf_Word v1, elfcpp::Elf_Word v2);
+
+ // Merge processor-specific flags from input object and those in the ELF
+ // header of the output.
+ void
+ merge_processor_specific_flags(const std::string&, elfcpp::Elf_Word);
+
+ // Get the secondary compatible architecture.
+ static int
+ get_secondary_compatible_arch(const Attributes_section_data*);
+
+ // Set the secondary compatible architecture.
+ static void
+ set_secondary_compatible_arch(Attributes_section_data*, int);
+
+ static int
+ tag_cpu_arch_combine(const char*, int, int*, int, int);
+
+ // Helper to print AEABI enum tag value.
+ static std::string
+ aeabi_enum_name(unsigned int);
+
+ // Return string value for TAG_CPU_name.
+ static std::string
+ tag_cpu_name_value(unsigned int);
+
+ // Merge object attributes from input object and those in the output.
+ void
+ merge_object_attributes(const char*, const Attributes_section_data*);
+
+ // Helper to get an AEABI object attribute
+ Object_attribute*
+ get_aeabi_object_attribute(int tag) const
+ {
+ Attributes_section_data* pasd = this->attributes_section_data_;
+ gold_assert(pasd != NULL);
+ Object_attribute* attr =
+ pasd->get_attribute(Object_attribute::OBJ_ATTR_PROC, tag);
+ gold_assert(attr != NULL);
+ return attr;
+ }
+
+ //
+ // Methods to support stub-generations.
+ //
+
+ // Group input sections for stub generation.
+ void
+ group_sections(Layout*, section_size_type, bool);
+
+ // Scan a relocation for stub generation.
+ void
+ scan_reloc_for_stub(const Relocate_info<32, big_endian>*, unsigned int,
+ const Sized_symbol<32>*, unsigned int,
+ const Symbol_value<32>*,
+ elfcpp::Elf_types<32>::Elf_Swxword, Arm_address);
+
+ // Scan a relocation section for stub.
+ template<int sh_type>
+ void
+ scan_reloc_section_for_stubs(
+ const Relocate_info<32, big_endian>* relinfo,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ const unsigned char* view,
+ elfcpp::Elf_types<32>::Elf_Addr view_address,
+ section_size_type);
+
+ // Fix .ARM.exidx section coverage.
+ void
+ fix_exidx_coverage(Layout*, const Input_objects*,
+ Arm_output_section<big_endian>*, Symbol_table*);
+
+ // Functors for STL set.
+ struct output_section_address_less_than
+ {
+ bool
+ operator()(const Output_section* s1, const Output_section* s2) const
+ { return s1->address() < s2->address(); }
+ };
+
+ // Information about this specific target which we pass to the
+ // general Target structure.
+ static const Target::Target_info arm_info;
+
+ // The types of GOT entries needed for this platform.
+ enum Got_type
+ {
+ GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
+ GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
+ GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
+ GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
+ GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
+ };
+
+ typedef typename std::vector<Stub_table<big_endian>*> Stub_table_list;
+
+ // Map input section to Arm_input_section.
+ typedef Unordered_map<Section_id,
+ Arm_input_section<big_endian>*,
+ Section_id_hash>
+ Arm_input_section_map;
+
+ // Map output addresses to relocs for Cortex-A8 erratum.
+ typedef Unordered_map<Arm_address, const Cortex_a8_reloc*>
+ Cortex_a8_relocs_info;
+
+ // The GOT section.
+ Arm_output_data_got<big_endian>* got_;
+ // The PLT section.
+ Output_data_plt_arm<big_endian>* plt_;
+ // The GOT PLT section.
+ Output_data_space* got_plt_;
+ // The dynamic reloc section.
+ Reloc_section* rel_dyn_;
+ // Relocs saved to avoid a COPY reloc.
+ Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
+ // Space for variables copied with a COPY reloc.
+ Output_data_space* dynbss_;
+ // Offset of the GOT entry for the TLS module index.
+ unsigned int got_mod_index_offset_;
+ // True if the _TLS_MODULE_BASE_ symbol has been defined.
+ bool tls_base_symbol_defined_;
+ // Vector of Stub_tables created.
+ Stub_table_list stub_tables_;
+ // Stub factory.
+ const Stub_factory &stub_factory_;
+ // Whether we can use BLX.
+ bool may_use_blx_;
+ // Whether we force PIC branch veneers.
+ bool should_force_pic_veneer_;
+ // Map for locating Arm_input_sections.
+ Arm_input_section_map arm_input_section_map_;
+ // Attributes section data in output.
+ Attributes_section_data* attributes_section_data_;
+ // Whether we want to fix code for Cortex-A8 erratum.
+ bool fix_cortex_a8_;
+ // Map addresses to relocs for Cortex-A8 erratum.
+ Cortex_a8_relocs_info cortex_a8_relocs_info_;
+};
+
+template<bool big_endian>
+const Target::Target_info Target_arm<big_endian>::arm_info =
+{
+ 32, // size
+ big_endian, // is_big_endian
+ elfcpp::EM_ARM, // machine_code
+ false, // has_make_symbol
+ false, // has_resolve
+ false, // has_code_fill
+ true, // is_default_stack_executable
+ '\0', // wrap_char
+ "/usr/lib/libc.so.1", // dynamic_linker
+ 0x8000, // default_text_segment_address
+ 0x1000, // abi_pagesize (overridable by -z max-page-size)
+ 0x1000, // common_pagesize (overridable by -z common-page-size)
+ elfcpp::SHN_UNDEF, // small_common_shndx
+ elfcpp::SHN_UNDEF, // large_common_shndx
+ 0, // small_common_section_flags
+ 0, // large_common_section_flags
+ ".ARM.attributes", // attributes_section
+ "aeabi" // attributes_vendor
+};
+
+// Arm relocate functions class
+//
+
+template<bool big_endian>
+class Arm_relocate_functions : public Relocate_functions<32, big_endian>
+{
+ public:
+ typedef enum
+ {
+ STATUS_OKAY, // No error during relocation.
+ STATUS_OVERFLOW, // Relocation oveflow.
+ STATUS_BAD_RELOC // Relocation cannot be applied.
+ } Status;
+
+ private:
+ typedef Relocate_functions<32, big_endian> Base;
+ typedef Arm_relocate_functions<big_endian> This;
+
+ // Encoding of imm16 argument for movt and movw ARM instructions
+ // from ARM ARM:
+ //
+ // imm16 := imm4 | imm12
+ //
+ // f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0
+ // +-------+---------------+-------+-------+-----------------------+
+ // | | |imm4 | |imm12 |
+ // +-------+---------------+-------+-------+-----------------------+
+
+ // Extract the relocation addend from VAL based on the ARM
+ // instruction encoding described above.
+ static inline typename elfcpp::Swap<32, big_endian>::Valtype
+ extract_arm_movw_movt_addend(
+ typename elfcpp::Swap<32, big_endian>::Valtype val)
+ {
+ // According to the Elf ABI for ARM Architecture the immediate
+ // field is sign-extended to form the addend.
+ return utils::sign_extend<16>(((val >> 4) & 0xf000) | (val & 0xfff));
+ }
+
+ // Insert X into VAL based on the ARM instruction encoding described
+ // above.
+ static inline typename elfcpp::Swap<32, big_endian>::Valtype
+ insert_val_arm_movw_movt(
+ typename elfcpp::Swap<32, big_endian>::Valtype val,
+ typename elfcpp::Swap<32, big_endian>::Valtype x)
+ {
+ val &= 0xfff0f000;
+ val |= x & 0x0fff;
+ val |= (x & 0xf000) << 4;
+ return val;
+ }
+
+ // Encoding of imm16 argument for movt and movw Thumb2 instructions
+ // from ARM ARM:
+ //
+ // imm16 := imm4 | i | imm3 | imm8
+ //
+ // f e d c b a 9 8 7 6 5 4 3 2 1 0 f e d c b a 9 8 7 6 5 4 3 2 1 0
+ // +---------+-+-----------+-------++-+-----+-------+---------------+
+ // | |i| |imm4 || |imm3 | |imm8 |
+ // +---------+-+-----------+-------++-+-----+-------+---------------+
+
+ // Extract the relocation addend from VAL based on the Thumb2
+ // instruction encoding described above.
+ static inline typename elfcpp::Swap<32, big_endian>::Valtype
+ extract_thumb_movw_movt_addend(
+ typename elfcpp::Swap<32, big_endian>::Valtype val)
+ {
+ // According to the Elf ABI for ARM Architecture the immediate
+ // field is sign-extended to form the addend.
+ return utils::sign_extend<16>(((val >> 4) & 0xf000)
+ | ((val >> 15) & 0x0800)
+ | ((val >> 4) & 0x0700)
+ | (val & 0x00ff));
+ }
+
+ // Insert X into VAL based on the Thumb2 instruction encoding
+ // described above.
+ static inline typename elfcpp::Swap<32, big_endian>::Valtype
+ insert_val_thumb_movw_movt(
+ typename elfcpp::Swap<32, big_endian>::Valtype val,
+ typename elfcpp::Swap<32, big_endian>::Valtype x)
+ {
+ val &= 0xfbf08f00;
+ val |= (x & 0xf000) << 4;
+ val |= (x & 0x0800) << 15;
+ val |= (x & 0x0700) << 4;
+ val |= (x & 0x00ff);
+ return val;
+ }
+
+ // Calculate the smallest constant Kn for the specified residual.
+ // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
+ static uint32_t
+ calc_grp_kn(typename elfcpp::Swap<32, big_endian>::Valtype residual)
+ {
+ int32_t msb;
+
+ if (residual == 0)
+ return 0;
+ // Determine the most significant bit in the residual and
+ // align the resulting value to a 2-bit boundary.
+ for (msb = 30; (msb >= 0) && !(residual & (3 << msb)); msb -= 2)
+ ;
+ // The desired shift is now (msb - 6), or zero, whichever
+ // is the greater.
+ return (((msb - 6) < 0) ? 0 : (msb - 6));
+ }
+
+ // Calculate the final residual for the specified group index.
+ // If the passed group index is less than zero, the method will return
+ // the value of the specified residual without any change.
+ // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
+ static typename elfcpp::Swap<32, big_endian>::Valtype
+ calc_grp_residual(typename elfcpp::Swap<32, big_endian>::Valtype residual,
+ const int group)
+ {
+ for (int n = 0; n <= group; n++)
+ {
+ // Calculate which part of the value to mask.
+ uint32_t shift = calc_grp_kn(residual);
+ // Calculate the residual for the next time around.
+ residual &= ~(residual & (0xff << shift));
+ }
+
+ return residual;
+ }
+
+ // Calculate the value of Gn for the specified group index.
+ // We return it in the form of an encoded constant-and-rotation.
+ // (see (AAELF 4.6.1.4 Static ARM relocations, Group Relocations, p.32)
+ static typename elfcpp::Swap<32, big_endian>::Valtype
+ calc_grp_gn(typename elfcpp::Swap<32, big_endian>::Valtype residual,
+ const int group)
+ {
+ typename elfcpp::Swap<32, big_endian>::Valtype gn = 0;
+ uint32_t shift = 0;
+
+ for (int n = 0; n <= group; n++)
+ {
+ // Calculate which part of the value to mask.
+ shift = calc_grp_kn(residual);
+ // Calculate Gn in 32-bit as well as encoded constant-and-rotation form.
+ gn = residual & (0xff << shift);
+ // Calculate the residual for the next time around.
+ residual &= ~gn;
+ }
+ // Return Gn in the form of an encoded constant-and-rotation.
+ return ((gn >> shift) | ((gn <= 0xff ? 0 : (32 - shift) / 2) << 8));
+ }
+
+ public:
+ // Handle ARM long branches.
+ static typename This::Status
+ arm_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
+ unsigned char *, const Sized_symbol<32>*,
+ const Arm_relobj<big_endian>*, unsigned int,
+ const Symbol_value<32>*, Arm_address, Arm_address, bool);
+
+ // Handle THUMB long branches.
+ static typename This::Status
+ thumb_branch_common(unsigned int, const Relocate_info<32, big_endian>*,
+ unsigned char *, const Sized_symbol<32>*,
+ const Arm_relobj<big_endian>*, unsigned int,
+ const Symbol_value<32>*, Arm_address, Arm_address, bool);
+
+
+ // Return the branch offset of a 32-bit THUMB branch.
+ static inline int32_t
+ thumb32_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
+ {
+ // We use the Thumb-2 encoding (backwards compatible with Thumb-1)
+ // involving the J1 and J2 bits.
+ uint32_t s = (upper_insn & (1U << 10)) >> 10;
+ uint32_t upper = upper_insn & 0x3ffU;
+ uint32_t lower = lower_insn & 0x7ffU;
+ uint32_t j1 = (lower_insn & (1U << 13)) >> 13;
+ uint32_t j2 = (lower_insn & (1U << 11)) >> 11;
+ uint32_t i1 = j1 ^ s ? 0 : 1;
+ uint32_t i2 = j2 ^ s ? 0 : 1;
+
+ return utils::sign_extend<25>((s << 24) | (i1 << 23) | (i2 << 22)
+ | (upper << 12) | (lower << 1));
+ }
+
+ // Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
+ // UPPER_INSN is the original upper instruction of the branch. Caller is
+ // responsible for overflow checking and BLX offset adjustment.
+ static inline uint16_t
+ thumb32_branch_upper(uint16_t upper_insn, int32_t offset)
+ {
+ uint32_t s = offset < 0 ? 1 : 0;
+ uint32_t bits = static_cast<uint32_t>(offset);
+ return (upper_insn & ~0x7ffU) | ((bits >> 12) & 0x3ffU) | (s << 10);
+ }
+
+ // Insert OFFSET to a 32-bit THUMB branch and return the lower instruction.
+ // LOWER_INSN is the original lower instruction of the branch. Caller is
+ // responsible for overflow checking and BLX offset adjustment.
+ static inline uint16_t
+ thumb32_branch_lower(uint16_t lower_insn, int32_t offset)
+ {
+ uint32_t s = offset < 0 ? 1 : 0;
+ uint32_t bits = static_cast<uint32_t>(offset);
+ return ((lower_insn & ~0x2fffU)
+ | ((((bits >> 23) & 1) ^ !s) << 13)
+ | ((((bits >> 22) & 1) ^ !s) << 11)
+ | ((bits >> 1) & 0x7ffU));
+ }
+
+ // Return the branch offset of a 32-bit THUMB conditional branch.
+ static inline int32_t
+ thumb32_cond_branch_offset(uint16_t upper_insn, uint16_t lower_insn)
+ {
+ uint32_t s = (upper_insn & 0x0400U) >> 10;
+ uint32_t j1 = (lower_insn & 0x2000U) >> 13;
+ uint32_t j2 = (lower_insn & 0x0800U) >> 11;
+ uint32_t lower = (lower_insn & 0x07ffU);
+ uint32_t upper = (s << 8) | (j2 << 7) | (j1 << 6) | (upper_insn & 0x003fU);
+
+ return utils::sign_extend<21>((upper << 12) | (lower << 1));
+ }
+
+ // Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
+ // instruction. UPPER_INSN is the original upper instruction of the branch.
+ // Caller is responsible for overflow checking.
+ static inline uint16_t
+ thumb32_cond_branch_upper(uint16_t upper_insn, int32_t offset)
+ {
+ uint32_t s = offset < 0 ? 1 : 0;
+ uint32_t bits = static_cast<uint32_t>(offset);
+ return (upper_insn & 0xfbc0U) | (s << 10) | ((bits & 0x0003f000U) >> 12);
+ }
+
+ // Insert OFFSET to a 32-bit THUMB conditional branch and return the lower
+ // instruction. LOWER_INSN is the original lower instruction of the branch.
+ // Caller is reponsible for overflow checking.
+ static inline uint16_t
+ thumb32_cond_branch_lower(uint16_t lower_insn, int32_t offset)
+ {
+ uint32_t bits = static_cast<uint32_t>(offset);
+ uint32_t j2 = (bits & 0x00080000U) >> 19;
+ uint32_t j1 = (bits & 0x00040000U) >> 18;
+ uint32_t lo = (bits & 0x00000ffeU) >> 1;
+
+ return (lower_insn & 0xd000U) | (j1 << 13) | (j2 << 11) | lo;
+ }
+
+ // R_ARM_ABS8: S + A
+ static inline typename This::Status
+ abs8(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval)
+ {
+ typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
+ Reltype addend = utils::sign_extend<8>(val);
+ Reltype x = psymval->value(object, addend);
+ val = utils::bit_select(val, x, 0xffU);
+ elfcpp::Swap<8, big_endian>::writeval(wv, val);
+
+ // R_ARM_ABS8 permits signed or unsigned results.
+ int signed_x = static_cast<int32_t>(x);
+ return ((signed_x < -128 || signed_x > 255)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_THM_ABS5: S + A
+ static inline typename This::Status
+ thm_abs5(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
+ Reltype addend = (val & 0x7e0U) >> 6;
+ Reltype x = psymval->value(object, addend);
+ val = utils::bit_select(val, x << 6, 0x7e0U);
+ elfcpp::Swap<16, big_endian>::writeval(wv, val);
+
+ // R_ARM_ABS16 permits signed or unsigned results.
+ int signed_x = static_cast<int32_t>(x);
+ return ((signed_x < -32768 || signed_x > 65535)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_ABS12: S + A
+ static inline typename This::Status
+ abs12(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval)
+ {
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
+ Reltype addend = val & 0x0fffU;
+ Reltype x = psymval->value(object, addend);
+ val = utils::bit_select(val, x, 0x0fffU);
+ elfcpp::Swap<32, big_endian>::writeval(wv, val);
+ return (utils::has_overflow<12>(x)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_ABS16: S + A
+ static inline typename This::Status
+ abs16(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
+ Reltype addend = utils::sign_extend<16>(val);
+ Reltype x = psymval->value(object, addend);
+ val = utils::bit_select(val, x, 0xffffU);
+ elfcpp::Swap<16, big_endian>::writeval(wv, val);
+ return (utils::has_signed_unsigned_overflow<16>(x)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_ABS32: (S + A) | T
+ static inline typename This::Status
+ abs32(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address thumb_bit)
+ {
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
+ Valtype x = psymval->value(object, addend) | thumb_bit;
+ elfcpp::Swap<32, big_endian>::writeval(wv, x);
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_REL32: (S + A) | T - P
+ static inline typename This::Status
+ rel32(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address address,
+ Arm_address thumb_bit)
+ {
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype addend = elfcpp::Swap<32, big_endian>::readval(wv);
+ Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
+ elfcpp::Swap<32, big_endian>::writeval(wv, x);
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_THM_JUMP24: (S + A) | T - P
+ static typename This::Status
+ thm_jump19(unsigned char *view, const Arm_relobj<big_endian>* object,
+ const Symbol_value<32>* psymval, Arm_address address,
+ Arm_address thumb_bit);
+
+ // R_ARM_THM_JUMP6: S + A – P
+ static inline typename This::Status
+ thm_jump6(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address address)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
+ // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
+ Reltype addend = (((val & 0x0200) >> 3) | ((val & 0x00f8) >> 2));
+ Reltype x = (psymval->value(object, addend) - address);
+ val = (val & 0xfd07) | ((x & 0x0040) << 3) | ((val & 0x003e) << 2);
+ elfcpp::Swap<16, big_endian>::writeval(wv, val);
+ // CZB does only forward jumps.
+ return ((x > 0x007e)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_THM_JUMP8: S + A – P
+ static inline typename This::Status
+ thm_jump8(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address address)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
+ Reltype addend = utils::sign_extend<8>((val & 0x00ff) << 1);
+ Reltype x = (psymval->value(object, addend) - address);
+ elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xff00) | ((x & 0x01fe) >> 1));
+ return (utils::has_overflow<8>(x)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_THM_JUMP11: S + A – P
+ static inline typename This::Status
+ thm_jump11(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address address)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
+ Reltype addend = utils::sign_extend<11>((val & 0x07ff) << 1);
+ Reltype x = (psymval->value(object, addend) - address);
+ elfcpp::Swap<16, big_endian>::writeval(wv, (val & 0xf800) | ((x & 0x0ffe) >> 1));
+ return (utils::has_overflow<11>(x)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_BASE_PREL: B(S) + A - P
+ static inline typename This::Status
+ base_prel(unsigned char* view,
+ Arm_address origin,
+ Arm_address address)
+ {
+ Base::rel32(view, origin - address);
+ return STATUS_OKAY;
+ }
+
+ // R_ARM_BASE_ABS: B(S) + A
+ static inline typename This::Status
+ base_abs(unsigned char* view,
+ Arm_address origin)
+ {
+ Base::rel32(view, origin);
+ return STATUS_OKAY;
+ }
+
+ // R_ARM_GOT_BREL: GOT(S) + A - GOT_ORG
+ static inline typename This::Status
+ got_brel(unsigned char* view,
+ typename elfcpp::Swap<32, big_endian>::Valtype got_offset)
+ {
+ Base::rel32(view, got_offset);
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_GOT_PREL: GOT(S) + A - P
+ static inline typename This::Status
+ got_prel(unsigned char *view,
+ Arm_address got_entry,
+ Arm_address address)
+ {
+ Base::rel32(view, got_entry - address);
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_PREL: (S + A) | T - P
+ static inline typename This::Status
+ prel31(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address address,
+ Arm_address thumb_bit)
+ {
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
+ Valtype addend = utils::sign_extend<31>(val);
+ Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
+ val = utils::bit_select(val, x, 0x7fffffffU);
+ elfcpp::Swap<32, big_endian>::writeval(wv, val);
+ return (utils::has_overflow<31>(x) ?
+ This::STATUS_OVERFLOW : This::STATUS_OKAY);
+ }
+
+ // R_ARM_MOVW_ABS_NC: (S + A) | T (relative address base is )
+ // R_ARM_MOVW_PREL_NC: (S + A) | T - P
+ // R_ARM_MOVW_BREL_NC: ((S + A) | T) - B(S)
+ // R_ARM_MOVW_BREL: ((S + A) | T) - B(S)
+ static inline typename This::Status
+ movw(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address relative_address_base,
+ Arm_address thumb_bit,
+ bool check_overflow)
+ {
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
+ Valtype addend = This::extract_arm_movw_movt_addend(val);
+ Valtype x = ((psymval->value(object, addend) | thumb_bit)
+ - relative_address_base);
+ val = This::insert_val_arm_movw_movt(val, x);
+ elfcpp::Swap<32, big_endian>::writeval(wv, val);
+ return ((check_overflow && utils::has_overflow<16>(x))
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_MOVT_ABS: S + A (relative address base is 0)
+ // R_ARM_MOVT_PREL: S + A - P
+ // R_ARM_MOVT_BREL: S + A - B(S)
+ static inline typename This::Status
+ movt(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address relative_address_base)
+ {
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
+ Valtype addend = This::extract_arm_movw_movt_addend(val);
+ Valtype x = (psymval->value(object, addend) - relative_address_base) >> 16;
+ val = This::insert_val_arm_movw_movt(val, x);
+ elfcpp::Swap<32, big_endian>::writeval(wv, val);
+ // FIXME: IHI0044D says that we should check for overflow.
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_THM_MOVW_ABS_NC: S + A | T (relative_address_base is 0)
+ // R_ARM_THM_MOVW_PREL_NC: (S + A) | T - P
+ // R_ARM_THM_MOVW_BREL_NC: ((S + A) | T) - B(S)
+ // R_ARM_THM_MOVW_BREL: ((S + A) | T) - B(S)
+ static inline typename This::Status
+ thm_movw(unsigned char *view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address relative_address_base,
+ Arm_address thumb_bit,
+ bool check_overflow)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
+ | elfcpp::Swap<16, big_endian>::readval(wv + 1);
+ Reltype addend = This::extract_thumb_movw_movt_addend(val);
+ Reltype x =
+ (psymval->value(object, addend) | thumb_bit) - relative_address_base;
+ val = This::insert_val_thumb_movw_movt(val, x);
+ elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
+ elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
+ return ((check_overflow && utils::has_overflow<16>(x))
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_THM_MOVT_ABS: S + A (relative address base is 0)
+ // R_ARM_THM_MOVT_PREL: S + A - P
+ // R_ARM_THM_MOVT_BREL: S + A - B(S)
+ static inline typename This::Status
+ thm_movt(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address relative_address_base)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Reltype val = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
+ | elfcpp::Swap<16, big_endian>::readval(wv + 1);
+ Reltype addend = This::extract_thumb_movw_movt_addend(val);
+ Reltype x = (psymval->value(object, addend) - relative_address_base) >> 16;
+ val = This::insert_val_thumb_movw_movt(val, x);
+ elfcpp::Swap<16, big_endian>::writeval(wv, val >> 16);
+ elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_THM_ALU_PREL_11_0: ((S + A) | T) - Pa (Thumb32)
+ static inline typename This::Status
+ thm_alu11(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address address,
+ Arm_address thumb_bit)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
+ | elfcpp::Swap<16, big_endian>::readval(wv + 1);
+
+ // f e d c b|a|9|8 7 6 5|4|3 2 1 0||f|e d c|b a 9 8|7 6 5 4 3 2 1 0
+ // -----------------------------------------------------------------------
+ // ADD{S} 1 1 1 1 0|i|0|1 0 0 0|S|1 1 0 1||0|imm3 |Rd |imm8
+ // ADDW 1 1 1 1 0|i|1|0 0 0 0|0|1 1 0 1||0|imm3 |Rd |imm8
+ // ADR[+] 1 1 1 1 0|i|1|0 0 0 0|0|1 1 1 1||0|imm3 |Rd |imm8
+ // SUB{S} 1 1 1 1 0|i|0|1 1 0 1|S|1 1 0 1||0|imm3 |Rd |imm8
+ // SUBW 1 1 1 1 0|i|1|0 1 0 1|0|1 1 0 1||0|imm3 |Rd |imm8
+ // ADR[-] 1 1 1 1 0|i|1|0 1 0 1|0|1 1 1 1||0|imm3 |Rd |imm8
+
+ // Determine a sign for the addend.
+ const int sign = ((insn & 0xf8ef0000) == 0xf0ad0000
+ || (insn & 0xf8ef0000) == 0xf0af0000) ? -1 : 1;
+ // Thumb2 addend encoding:
+ // imm12 := i | imm3 | imm8
+ int32_t addend = (insn & 0xff)
+ | ((insn & 0x00007000) >> 4)
+ | ((insn & 0x04000000) >> 15);
+ // Apply a sign to the added.
+ addend *= sign;
+
+ int32_t x = (psymval->value(object, addend) | thumb_bit)
+ - (address & 0xfffffffc);
+ Reltype val = abs(x);
+ // Mask out the value and a distinct part of the ADD/SUB opcode
+ // (bits 7:5 of opword).
+ insn = (insn & 0xfb0f8f00)
+ | (val & 0xff)
+ | ((val & 0x700) << 4)
+ | ((val & 0x800) << 15);
+ // Set the opcode according to whether the value to go in the
+ // place is negative.
+ if (x < 0)
+ insn |= 0x00a00000;
+
+ elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
+ elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
+ return ((val > 0xfff) ?
+ This::STATUS_OVERFLOW : This::STATUS_OKAY);
+ }
+
+ // R_ARM_THM_PC8: S + A - Pa (Thumb)
+ static inline typename This::Status
+ thm_pc8(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address address)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype insn = elfcpp::Swap<16, big_endian>::readval(wv);
+ Reltype addend = ((insn & 0x00ff) << 2);
+ int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
+ Reltype val = abs(x);
+ insn = (insn & 0xff00) | ((val & 0x03fc) >> 2);
+
+ elfcpp::Swap<16, big_endian>::writeval(wv, insn);
+ return ((val > 0x03fc)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+ }
+
+ // R_ARM_THM_PC12: S + A - Pa (Thumb32)
+ static inline typename This::Status
+ thm_pc12(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address address)
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Reltype insn = (elfcpp::Swap<16, big_endian>::readval(wv) << 16)
+ | elfcpp::Swap<16, big_endian>::readval(wv + 1);
+ // Determine a sign for the addend (positive if the U bit is 1).
+ const int sign = (insn & 0x00800000) ? 1 : -1;
+ int32_t addend = (insn & 0xfff);
+ // Apply a sign to the added.
+ addend *= sign;
+
+ int32_t x = (psymval->value(object, addend) - (address & 0xfffffffc));
+ Reltype val = abs(x);
+ // Mask out and apply the value and the U bit.
+ insn = (insn & 0xff7ff000) | (val & 0xfff);
+ // Set the U bit according to whether the value to go in the
+ // place is positive.
+ if (x >= 0)
+ insn |= 0x00800000;
+
+ elfcpp::Swap<16, big_endian>::writeval(wv, insn >> 16);
+ elfcpp::Swap<16, big_endian>::writeval(wv + 1, insn & 0xffff);
+ return ((val > 0xfff) ?
+ This::STATUS_OVERFLOW : This::STATUS_OKAY);
+ }
+
+ // R_ARM_V4BX
+ static inline typename This::Status
+ v4bx(const Relocate_info<32, big_endian>* relinfo,
+ unsigned char *view,
+ const Arm_relobj<big_endian>* object,
+ const Arm_address address,
+ const bool is_interworking)
+ {
+
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
+
+ // Ensure that we have a BX instruction.
+ gold_assert((val & 0x0ffffff0) == 0x012fff10);
+ const uint32_t reg = (val & 0xf);
+ if (is_interworking && reg != 0xf)
+ {
+ Stub_table<big_endian>* stub_table =
+ object->stub_table(relinfo->data_shndx);
+ gold_assert(stub_table != NULL);
+
+ Arm_v4bx_stub* stub = stub_table->find_arm_v4bx_stub(reg);
+ gold_assert(stub != NULL);
+
+ int32_t veneer_address =
+ stub_table->address() + stub->offset() - 8 - address;
+ gold_assert((veneer_address <= ARM_MAX_FWD_BRANCH_OFFSET)
+ && (veneer_address >= ARM_MAX_BWD_BRANCH_OFFSET));
+ // Replace with a branch to veneer (B <addr>)
+ val = (val & 0xf0000000) | 0x0a000000
+ | ((veneer_address >> 2) & 0x00ffffff);
+ }
+ else
+ {
+ // Preserve Rm (lowest four bits) and the condition code
+ // (highest four bits). Other bits encode MOV PC,Rm.
+ val = (val & 0xf000000f) | 0x01a0f000;
+ }
+ elfcpp::Swap<32, big_endian>::writeval(wv, val);
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_ALU_PC_G0_NC: ((S + A) | T) - P
+ // R_ARM_ALU_PC_G0: ((S + A) | T) - P
+ // R_ARM_ALU_PC_G1_NC: ((S + A) | T) - P
+ // R_ARM_ALU_PC_G1: ((S + A) | T) - P
+ // R_ARM_ALU_PC_G2: ((S + A) | T) - P
+ // R_ARM_ALU_SB_G0_NC: ((S + A) | T) - B(S)
+ // R_ARM_ALU_SB_G0: ((S + A) | T) - B(S)
+ // R_ARM_ALU_SB_G1_NC: ((S + A) | T) - B(S)
+ // R_ARM_ALU_SB_G1: ((S + A) | T) - B(S)
+ // R_ARM_ALU_SB_G2: ((S + A) | T) - B(S)
+ static inline typename This::Status
+ arm_grp_alu(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ const int group,
+ Arm_address address,
+ Arm_address thumb_bit,
+ bool check_overflow)
+ {
+ gold_assert(group >= 0 && group < 3);
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
+
+ // ALU group relocations are allowed only for the ADD/SUB instructions.
+ // (0x00800000 - ADD, 0x00400000 - SUB)
+ const Valtype opcode = insn & 0x01e00000;
+ if (opcode != 0x00800000 && opcode != 0x00400000)
+ return This::STATUS_BAD_RELOC;
+
+ // Determine a sign for the addend.
+ const int sign = (opcode == 0x00800000) ? 1 : -1;
+ // shifter = rotate_imm * 2
+ const uint32_t shifter = (insn & 0xf00) >> 7;
+ // Initial addend value.
+ int32_t addend = insn & 0xff;
+ // Rotate addend right by shifter.
+ addend = (addend >> shifter) | (addend << (32 - shifter));
+ // Apply a sign to the added.
+ addend *= sign;
+
+ int32_t x = ((psymval->value(object, addend) | thumb_bit) - address);
+ Valtype gn = Arm_relocate_functions::calc_grp_gn(abs(x), group);
+ // Check for overflow if required
+ if (check_overflow
+ && (Arm_relocate_functions::calc_grp_residual(abs(x), group) != 0))
+ return This::STATUS_OVERFLOW;
+
+ // Mask out the value and the ADD/SUB part of the opcode; take care
+ // not to destroy the S bit.
+ insn &= 0xff1ff000;
+ // Set the opcode according to whether the value to go in the
+ // place is negative.
+ insn |= ((x < 0) ? 0x00400000 : 0x00800000);
+ // Encode the offset (encoded Gn).
+ insn |= gn;
+
+ elfcpp::Swap<32, big_endian>::writeval(wv, insn);
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_LDR_PC_G0: S + A - P
+ // R_ARM_LDR_PC_G1: S + A - P
+ // R_ARM_LDR_PC_G2: S + A - P
+ // R_ARM_LDR_SB_G0: S + A - B(S)
+ // R_ARM_LDR_SB_G1: S + A - B(S)
+ // R_ARM_LDR_SB_G2: S + A - B(S)
+ static inline typename This::Status
+ arm_grp_ldr(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ const int group,
+ Arm_address address)
+ {
+ gold_assert(group >= 0 && group < 3);
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
+
+ const int sign = (insn & 0x00800000) ? 1 : -1;
+ int32_t addend = (insn & 0xfff) * sign;
+ int32_t x = (psymval->value(object, addend) - address);
+ // Calculate the relevant G(n-1) value to obtain this stage residual.
+ Valtype residual =
+ Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
+ if (residual >= 0x1000)
+ return This::STATUS_OVERFLOW;
+
+ // Mask out the value and U bit.
+ insn &= 0xff7ff000;
+ // Set the U bit for non-negative values.
+ if (x >= 0)
+ insn |= 0x00800000;
+ insn |= residual;
+
+ elfcpp::Swap<32, big_endian>::writeval(wv, insn);
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_LDRS_PC_G0: S + A - P
+ // R_ARM_LDRS_PC_G1: S + A - P
+ // R_ARM_LDRS_PC_G2: S + A - P
+ // R_ARM_LDRS_SB_G0: S + A - B(S)
+ // R_ARM_LDRS_SB_G1: S + A - B(S)
+ // R_ARM_LDRS_SB_G2: S + A - B(S)
+ static inline typename This::Status
+ arm_grp_ldrs(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ const int group,
+ Arm_address address)
+ {
+ gold_assert(group >= 0 && group < 3);
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
+
+ const int sign = (insn & 0x00800000) ? 1 : -1;
+ int32_t addend = (((insn & 0xf00) >> 4) + (insn & 0xf)) * sign;
+ int32_t x = (psymval->value(object, addend) - address);
+ // Calculate the relevant G(n-1) value to obtain this stage residual.
+ Valtype residual =
+ Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
+ if (residual >= 0x100)
+ return This::STATUS_OVERFLOW;
+
+ // Mask out the value and U bit.
+ insn &= 0xff7ff0f0;
+ // Set the U bit for non-negative values.
+ if (x >= 0)
+ insn |= 0x00800000;
+ insn |= ((residual & 0xf0) << 4) | (residual & 0xf);
+
+ elfcpp::Swap<32, big_endian>::writeval(wv, insn);
+ return This::STATUS_OKAY;
+ }
+
+ // R_ARM_LDC_PC_G0: S + A - P
+ // R_ARM_LDC_PC_G1: S + A - P
+ // R_ARM_LDC_PC_G2: S + A - P
+ // R_ARM_LDC_SB_G0: S + A - B(S)
+ // R_ARM_LDC_SB_G1: S + A - B(S)
+ // R_ARM_LDC_SB_G2: S + A - B(S)
+ static inline typename This::Status
+ arm_grp_ldc(unsigned char* view,
+ const Sized_relobj<32, big_endian>* object,
+ const Symbol_value<32>* psymval,
+ const int group,
+ Arm_address address)
+ {
+ gold_assert(group >= 0 && group < 3);
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
+
+ const int sign = (insn & 0x00800000) ? 1 : -1;
+ int32_t addend = ((insn & 0xff) << 2) * sign;
+ int32_t x = (psymval->value(object, addend) - address);
+ // Calculate the relevant G(n-1) value to obtain this stage residual.
+ Valtype residual =
+ Arm_relocate_functions::calc_grp_residual(abs(x), group - 1);
+ if ((residual & 0x3) != 0 || residual >= 0x400)
+ return This::STATUS_OVERFLOW;
+
+ // Mask out the value and U bit.
+ insn &= 0xff7fff00;
+ // Set the U bit for non-negative values.
+ if (x >= 0)
+ insn |= 0x00800000;
+ insn |= (residual >> 2);
+
+ elfcpp::Swap<32, big_endian>::writeval(wv, insn);
+ return This::STATUS_OKAY;
+ }
+};
+
+// Relocate ARM long branches. This handles relocation types
+// R_ARM_CALL, R_ARM_JUMP24, R_ARM_PLT32 and R_ARM_XPC25.
+// If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
+// undefined and we do not use PLT in this relocation. In such a case,
+// the branch is converted into an NOP.
+
+template<bool big_endian>
+typename Arm_relocate_functions<big_endian>::Status
+Arm_relocate_functions<big_endian>::arm_branch_common(
+ unsigned int r_type,
+ const Relocate_info<32, big_endian>* relinfo,
+ unsigned char *view,
+ const Sized_symbol<32>* gsym,
+ const Arm_relobj<big_endian>* object,
+ unsigned int r_sym,
+ const Symbol_value<32>* psymval,
+ Arm_address address,
+ Arm_address thumb_bit,
+ bool is_weakly_undefined_without_plt)
+{
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
+
+ bool insn_is_b = (((val >> 28) & 0xf) <= 0xe)
+ && ((val & 0x0f000000UL) == 0x0a000000UL);
+ bool insn_is_uncond_bl = (val & 0xff000000UL) == 0xeb000000UL;
+ bool insn_is_cond_bl = (((val >> 28) & 0xf) < 0xe)
+ && ((val & 0x0f000000UL) == 0x0b000000UL);
+ bool insn_is_blx = (val & 0xfe000000UL) == 0xfa000000UL;
+ bool insn_is_any_branch = (val & 0x0e000000UL) == 0x0a000000UL;
+
+ // Check that the instruction is valid.
+ if (r_type == elfcpp::R_ARM_CALL)
+ {
+ if (!insn_is_uncond_bl && !insn_is_blx)
+ return This::STATUS_BAD_RELOC;
+ }
+ else if (r_type == elfcpp::R_ARM_JUMP24)
+ {
+ if (!insn_is_b && !insn_is_cond_bl)
+ return This::STATUS_BAD_RELOC;
+ }
+ else if (r_type == elfcpp::R_ARM_PLT32)
+ {
+ if (!insn_is_any_branch)
+ return This::STATUS_BAD_RELOC;
+ }
+ else if (r_type == elfcpp::R_ARM_XPC25)
+ {
+ // FIXME: AAELF document IH0044C does not say much about it other
+ // than it being obsolete.
+ if (!insn_is_any_branch)
+ return This::STATUS_BAD_RELOC;
+ }
+ else
+ gold_unreachable();
+
+ // A branch to an undefined weak symbol is turned into a jump to
+ // the next instruction unless a PLT entry will be created.
+ // Do the same for local undefined symbols.
+ // The jump to the next instruction is optimized as a NOP depending
+ // on the architecture.
+ const Target_arm<big_endian>* arm_target =
+ Target_arm<big_endian>::default_target();
+ if (is_weakly_undefined_without_plt)
+ {
+ gold_assert(!parameters->options().relocatable());
+ Valtype cond = val & 0xf0000000U;
+ if (arm_target->may_use_arm_nop())
+ val = cond | 0x0320f000;
+ else
+ val = cond | 0x01a00000; // Using pre-UAL nop: mov r0, r0.
+ elfcpp::Swap<32, big_endian>::writeval(wv, val);
+ return This::STATUS_OKAY;
+ }
+
+ Valtype addend = utils::sign_extend<26>(val << 2);
+ Valtype branch_target = psymval->value(object, addend);
+ int32_t branch_offset = branch_target - address;
+
+ // We need a stub if the branch offset is too large or if we need
+ // to switch mode.
+ bool may_use_blx = arm_target->may_use_blx();
+ Reloc_stub* stub = NULL;
+
+ if (!parameters->options().relocatable()
+ && (utils::has_overflow<26>(branch_offset)
+ || ((thumb_bit != 0)
+ && !(may_use_blx && r_type == elfcpp::R_ARM_CALL))))
+ {
+ Valtype unadjusted_branch_target = psymval->value(object, 0);
+
+ Stub_type stub_type =
+ Reloc_stub::stub_type_for_reloc(r_type, address,
+ unadjusted_branch_target,
+ (thumb_bit != 0));
+ if (stub_type != arm_stub_none)
+ {
+ Stub_table<big_endian>* stub_table =
+ object->stub_table(relinfo->data_shndx);
+ gold_assert(stub_table != NULL);
+
+ Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
+ stub = stub_table->find_reloc_stub(stub_key);
+ gold_assert(stub != NULL);
+ thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
+ branch_target = stub_table->address() + stub->offset() + addend;
+ branch_offset = branch_target - address;
+ gold_assert(!utils::has_overflow<26>(branch_offset));
+ }
+ }
+
+ // At this point, if we still need to switch mode, the instruction
+ // must either be a BLX or a BL that can be converted to a BLX.
+ if (thumb_bit != 0)
+ {
+ // Turn BL to BLX.
+ gold_assert(may_use_blx && r_type == elfcpp::R_ARM_CALL);
+ val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23);
+ }
+
+ val = utils::bit_select(val, (branch_offset >> 2), 0xffffffUL);
+ elfcpp::Swap<32, big_endian>::writeval(wv, val);
+ return (utils::has_overflow<26>(branch_offset)
+ ? This::STATUS_OVERFLOW : This::STATUS_OKAY);
+}
+
+// Relocate THUMB long branches. This handles relocation types
+// R_ARM_THM_CALL, R_ARM_THM_JUMP24 and R_ARM_THM_XPC22.
+// If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
+// undefined and we do not use PLT in this relocation. In such a case,
+// the branch is converted into an NOP.
+
+template<bool big_endian>
+typename Arm_relocate_functions<big_endian>::Status
+Arm_relocate_functions<big_endian>::thumb_branch_common(
+ unsigned int r_type,
+ const Relocate_info<32, big_endian>* relinfo,
+ unsigned char *view,
+ const Sized_symbol<32>* gsym,
+ const Arm_relobj<big_endian>* object,
+ unsigned int r_sym,
+ const Symbol_value<32>* psymval,
+ Arm_address address,
+ Arm_address thumb_bit,
+ bool is_weakly_undefined_without_plt)
+{
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
+ uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
+
+ // FIXME: These tests are too loose and do not take THUMB/THUMB-2 difference
+ // into account.
+ bool is_bl_insn = (lower_insn & 0x1000U) == 0x1000U;
+ bool is_blx_insn = (lower_insn & 0x1000U) == 0x0000U;
+
+ // Check that the instruction is valid.
+ if (r_type == elfcpp::R_ARM_THM_CALL)
+ {
+ if (!is_bl_insn && !is_blx_insn)
+ return This::STATUS_BAD_RELOC;
+ }
+ else if (r_type == elfcpp::R_ARM_THM_JUMP24)
+ {
+ // This cannot be a BLX.
+ if (!is_bl_insn)
+ return This::STATUS_BAD_RELOC;
+ }
+ else if (r_type == elfcpp::R_ARM_THM_XPC22)
+ {
+ // Check for Thumb to Thumb call.
+ if (!is_blx_insn)
+ return This::STATUS_BAD_RELOC;
+ if (thumb_bit != 0)
+ {
+ gold_warning(_("%s: Thumb BLX instruction targets "
+ "thumb function '%s'."),
+ object->name().c_str(),
+ (gsym ? gsym->name() : "(local)"));
+ // Convert BLX to BL.
+ lower_insn |= 0x1000U;
+ }
+ }
+ else
+ gold_unreachable();
+
+ // A branch to an undefined weak symbol is turned into a jump to
+ // the next instruction unless a PLT entry will be created.
+ // The jump to the next instruction is optimized as a NOP.W for
+ // Thumb-2 enabled architectures.
+ const Target_arm<big_endian>* arm_target =
+ Target_arm<big_endian>::default_target();
+ if (is_weakly_undefined_without_plt)
+ {
+ gold_assert(!parameters->options().relocatable());
+ if (arm_target->may_use_thumb2_nop())
+ {
+ elfcpp::Swap<16, big_endian>::writeval(wv, 0xf3af);
+ elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0x8000);
+ }
+ else
+ {
+ elfcpp::Swap<16, big_endian>::writeval(wv, 0xe000);
+ elfcpp::Swap<16, big_endian>::writeval(wv + 1, 0xbf00);
+ }
+ return This::STATUS_OKAY;
+ }
+
+ int32_t addend = This::thumb32_branch_offset(upper_insn, lower_insn);
+ Arm_address branch_target = psymval->value(object, addend);
+
+ // For BLX, bit 1 of target address comes from bit 1 of base address.
+ bool may_use_blx = arm_target->may_use_blx();
+ if (thumb_bit == 0 && may_use_blx)
+ branch_target = utils::bit_select(branch_target, address, 0x2);
+
+ int32_t branch_offset = branch_target - address;
+
+ // We need a stub if the branch offset is too large or if we need
+ // to switch mode.
+ bool thumb2 = arm_target->using_thumb2();
+ if (!parameters->options().relocatable()
+ && ((!thumb2 && utils::has_overflow<23>(branch_offset))
+ || (thumb2 && utils::has_overflow<25>(branch_offset))
+ || ((thumb_bit == 0)
+ && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
+ || r_type == elfcpp::R_ARM_THM_JUMP24))))
+ {
+ Arm_address unadjusted_branch_target = psymval->value(object, 0);
+
+ Stub_type stub_type =
+ Reloc_stub::stub_type_for_reloc(r_type, address,
+ unadjusted_branch_target,
+ (thumb_bit != 0));
+
+ if (stub_type != arm_stub_none)
+ {
+ Stub_table<big_endian>* stub_table =
+ object->stub_table(relinfo->data_shndx);
+ gold_assert(stub_table != NULL);
+
+ Reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
+ Reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
+ gold_assert(stub != NULL);
+ thumb_bit = stub->stub_template()->entry_in_thumb_mode() ? 1 : 0;
+ branch_target = stub_table->address() + stub->offset() + addend;
+ if (thumb_bit == 0 && may_use_blx)
+ branch_target = utils::bit_select(branch_target, address, 0x2);
+ branch_offset = branch_target - address;
+ }
+ }
+
+ // At this point, if we still need to switch mode, the instruction
+ // must either be a BLX or a BL that can be converted to a BLX.
+ if (thumb_bit == 0)
+ {
+ gold_assert(may_use_blx
+ && (r_type == elfcpp::R_ARM_THM_CALL
+ || r_type == elfcpp::R_ARM_THM_XPC22));
+ // Make sure this is a BLX.
+ lower_insn &= ~0x1000U;
+ }
+ else
+ {
+ // Make sure this is a BL.
+ lower_insn |= 0x1000U;
+ }
+
+ // For a BLX instruction, make sure that the relocation is rounded up
+ // to a word boundary. This follows the semantics of the instruction
+ // which specifies that bit 1 of the target address will come from bit
+ // 1 of the base address.
+ if ((lower_insn & 0x5000U) == 0x4000U)
+ gold_assert((branch_offset & 3) == 0);
+
+ // Put BRANCH_OFFSET back into the insn. Assumes two's complement.
+ // We use the Thumb-2 encoding, which is safe even if dealing with
+ // a Thumb-1 instruction by virtue of our overflow check above. */
+ upper_insn = This::thumb32_branch_upper(upper_insn, branch_offset);
+ lower_insn = This::thumb32_branch_lower(lower_insn, branch_offset);
+
+ elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
+ elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
+
+ gold_assert(!utils::has_overflow<25>(branch_offset));
+
+ return ((thumb2
+ ? utils::has_overflow<25>(branch_offset)
+ : utils::has_overflow<23>(branch_offset))
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+}
+
+// Relocate THUMB-2 long conditional branches.
+// If IS_WEAK_UNDEFINED_WITH_PLT is true. The target symbol is weakly
+// undefined and we do not use PLT in this relocation. In such a case,
+// the branch is converted into an NOP.
+
+template<bool big_endian>
+typename Arm_relocate_functions<big_endian>::Status
+Arm_relocate_functions<big_endian>::thm_jump19(
+ unsigned char *view,
+ const Arm_relobj<big_endian>* object,
+ const Symbol_value<32>* psymval,
+ Arm_address address,
+ Arm_address thumb_bit)
+{
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ uint32_t upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
+ uint32_t lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
+ int32_t addend = This::thumb32_cond_branch_offset(upper_insn, lower_insn);
+
+ Arm_address branch_target = psymval->value(object, addend);
+ int32_t branch_offset = branch_target - address;
+
+ // ??? Should handle interworking? GCC might someday try to
+ // use this for tail calls.
+ // FIXME: We do support thumb entry to PLT yet.
+ if (thumb_bit == 0)
+ {
+ gold_error(_("conditional branch to PLT in THUMB-2 not supported yet."));
+ return This::STATUS_BAD_RELOC;
+ }
+
+ // Put RELOCATION back into the insn.
+ upper_insn = This::thumb32_cond_branch_upper(upper_insn, branch_offset);
+ lower_insn = This::thumb32_cond_branch_lower(lower_insn, branch_offset);
+
+ // Put the relocated value back in the object file:
+ elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
+ elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
+
+ return (utils::has_overflow<21>(branch_offset)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
+}
+
+// Get the GOT section, creating it if necessary.
+
+template<bool big_endian>
+Arm_output_data_got<big_endian>*
+Target_arm<big_endian>::got_section(Symbol_table* symtab, Layout* layout)
+{
+ if (this->got_ == NULL)
+ {
+ gold_assert(symtab != NULL && layout != NULL);
+
+ this->got_ = new Arm_output_data_got<big_endian>(symtab, layout);
+
+ layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
+ (elfcpp::SHF_ALLOC
+ | elfcpp::SHF_WRITE),
+ this->got_, false, false, false, true);
+ // The old GNU linker creates a .got.plt section. We just
+ // create another set of data in the .got section. Note that we
+ // always create a PLT if we create a GOT, although the PLT
+ // might be empty.
+ this->got_plt_ = new Output_data_space(4, "** GOT PLT");
+ layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
+ (elfcpp::SHF_ALLOC
+ | elfcpp::SHF_WRITE),
+ this->got_plt_, false, false, false,
+ false);
+
+ // The first three entries are reserved.
+ this->got_plt_->set_current_data_size(3 * 4);
+
+ // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
+ symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
+ Symbol_table::PREDEFINED,
+ this->got_plt_,
+ 0, 0, elfcpp::STT_OBJECT,
+ elfcpp::STB_LOCAL,
+ elfcpp::STV_HIDDEN, 0,
+ false, false);
+ }
+ return this->got_;
+}
+
+// Get the dynamic reloc section, creating it if necessary.
+
+template<bool big_endian>
+typename Target_arm<big_endian>::Reloc_section*
+Target_arm<big_endian>::rel_dyn_section(Layout* layout)
+{
+ if (this->rel_dyn_ == NULL)
+ {
+ gold_assert(layout != NULL);
+ this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
+ layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
+ elfcpp::SHF_ALLOC, this->rel_dyn_, true,
+ false, false, false);
+ }
+ return this->rel_dyn_;
+}
+
+// Insn_template methods.
+
+// Return byte size of an instruction template.
+
+size_t
+Insn_template::size() const
+{
+ switch (this->type())
+ {
+ case THUMB16_TYPE:
+ case THUMB16_SPECIAL_TYPE:
+ return 2;
+ case ARM_TYPE:
+ case THUMB32_TYPE:
+ case DATA_TYPE:
+ return 4;
+ default:
+ gold_unreachable();
+ }
+}
+
+// Return alignment of an instruction template.
+
+unsigned
+Insn_template::alignment() const
+{
+ switch (this->type())
+ {
+ case THUMB16_TYPE:
+ case THUMB16_SPECIAL_TYPE:
+ case THUMB32_TYPE:
+ return 2;
+ case ARM_TYPE:
+ case DATA_TYPE:
+ return 4;
+ default:
+ gold_unreachable();
+ }
+}
+
+// Stub_template methods.
+
+Stub_template::Stub_template(
+ Stub_type type, const Insn_template* insns,
+ size_t insn_count)
+ : type_(type), insns_(insns), insn_count_(insn_count), alignment_(1),
+ entry_in_thumb_mode_(false), relocs_()
+{
+ off_t offset = 0;
+
+ // Compute byte size and alignment of stub template.
+ for (size_t i = 0; i < insn_count; i++)
+ {
+ unsigned insn_alignment = insns[i].alignment();
+ size_t insn_size = insns[i].size();
+ gold_assert((offset & (insn_alignment - 1)) == 0);
+ this->alignment_ = std::max(this->alignment_, insn_alignment);
+ switch (insns[i].type())
+ {
+ case Insn_template::THUMB16_TYPE:
+ case Insn_template::THUMB16_SPECIAL_TYPE:
+ if (i == 0)
+ this->entry_in_thumb_mode_ = true;
+ break;
+
+ case Insn_template::THUMB32_TYPE:
+ if (insns[i].r_type() != elfcpp::R_ARM_NONE)
+ this->relocs_.push_back(Reloc(i, offset));
+ if (i == 0)
+ this->entry_in_thumb_mode_ = true;
+ break;
+
+ case Insn_template::ARM_TYPE:
+ // Handle cases where the target is encoded within the
+ // instruction.
+ if (insns[i].r_type() == elfcpp::R_ARM_JUMP24)
+ this->relocs_.push_back(Reloc(i, offset));
+ break;
+
+ case Insn_template::DATA_TYPE:
+ // Entry point cannot be data.
+ gold_assert(i != 0);
+ this->relocs_.push_back(Reloc(i, offset));
+ break;
+
+ default:
+ gold_unreachable();
+ }
+ offset += insn_size;
+ }
+ this->size_ = offset;
+}
+
+// Stub methods.
+
+// Template to implement do_write for a specific target endianness.
+
+template<bool big_endian>
+void inline
+Stub::do_fixed_endian_write(unsigned char* view, section_size_type view_size)
+{
+ const Stub_template* stub_template = this->stub_template();
+ const Insn_template* insns = stub_template->insns();
+
+ // FIXME: We do not handle BE8 encoding yet.
+ unsigned char* pov = view;
+ for (size_t i = 0; i < stub_template->insn_count(); i++)
+ {
+ switch (insns[i].type())
+ {
+ case Insn_template::THUMB16_TYPE:
+ elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
+ break;
+ case Insn_template::THUMB16_SPECIAL_TYPE:
+ elfcpp::Swap<16, big_endian>::writeval(
+ pov,
+ this->thumb16_special(i));
+ break;
+ case Insn_template::THUMB32_TYPE:
+ {
+ uint32_t hi = (insns[i].data() >> 16) & 0xffff;
+ uint32_t lo = insns[i].data() & 0xffff;
+ elfcpp::Swap<16, big_endian>::writeval(pov, hi);
+ elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
+ }
+ break;
+ case Insn_template::ARM_TYPE:
+ case Insn_template::DATA_TYPE:
+ elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
+ break;
+ default:
+ gold_unreachable();
+ }
+ pov += insns[i].size();
+ }
+ gold_assert(static_cast<section_size_type>(pov - view) == view_size);
+}
+
+// Reloc_stub::Key methods.
+
+// Dump a Key as a string for debugging.
+
+std::string
+Reloc_stub::Key::name() const
+{
+ if (this->r_sym_ == invalid_index)
+ {
+ // Global symbol key name
+ // <stub-type>:<symbol name>:<addend>.
+ const std::string sym_name = this->u_.symbol->name();
+ // We need to print two hex number and two colons. So just add 100 bytes
+ // to the symbol name size.
+ size_t len = sym_name.size() + 100;
+ char* buffer = new char[len];
+ int c = snprintf(buffer, len, "%d:%s:%x", this->stub_type_,
+ sym_name.c_str(), this->addend_);
+ gold_assert(c > 0 && c < static_cast<int>(len));
+ delete[] buffer;
+ return std::string(buffer);
+ }
+ else
+ {
+ // local symbol key name
+ // <stub-type>:<object>:<r_sym>:<addend>.
+ const size_t len = 200;
+ char buffer[len];
+ int c = snprintf(buffer, len, "%d:%p:%u:%x", this->stub_type_,
+ this->u_.relobj, this->r_sym_, this->addend_);
+ gold_assert(c > 0 && c < static_cast<int>(len));
+ return std::string(buffer);
+ }
+}
+
+// Reloc_stub methods.
+
+// Determine the type of stub needed, if any, for a relocation of R_TYPE at
+// LOCATION to DESTINATION.
+// This code is based on the arm_type_of_stub function in
+// bfd/elf32-arm.c. We have changed the interface a liitle to keep the Stub
+// class simple.
+
+Stub_type
+Reloc_stub::stub_type_for_reloc(
+ unsigned int r_type,
+ Arm_address location,
+ Arm_address destination,
+ bool target_is_thumb)
+{
+ Stub_type stub_type = arm_stub_none;
+
+ // This is a bit ugly but we want to avoid using a templated class for
+ // big and little endianities.
+ bool may_use_blx;
+ bool should_force_pic_veneer;
+ bool thumb2;
+ bool thumb_only;
+ if (parameters->target().is_big_endian())
+ {
+ const Target_arm<true>* big_endian_target =
+ Target_arm<true>::default_target();
+ may_use_blx = big_endian_target->may_use_blx();
+ should_force_pic_veneer = big_endian_target->should_force_pic_veneer();
+ thumb2 = big_endian_target->using_thumb2();
+ thumb_only = big_endian_target->using_thumb_only();
+ }
+ else
+ {
+ const Target_arm<false>* little_endian_target =
+ Target_arm<false>::default_target();
+ may_use_blx = little_endian_target->may_use_blx();
+ should_force_pic_veneer = little_endian_target->should_force_pic_veneer();
+ thumb2 = little_endian_target->using_thumb2();
+ thumb_only = little_endian_target->using_thumb_only();
+ }
+
+ int64_t branch_offset;
+ if (r_type == elfcpp::R_ARM_THM_CALL || r_type == elfcpp::R_ARM_THM_JUMP24)
+ {
+ // For THUMB BLX instruction, bit 1 of target comes from bit 1 of the
+ // base address (instruction address + 4).
+ if ((r_type == elfcpp::R_ARM_THM_CALL) && may_use_blx && !target_is_thumb)
+ destination = utils::bit_select(destination, location, 0x2);
+ branch_offset = static_cast<int64_t>(destination) - location;
+
+ // Handle cases where:
+ // - this call goes too far (different Thumb/Thumb2 max
+ // distance)
+ // - it's a Thumb->Arm call and blx is not available, or it's a
+ // Thumb->Arm branch (not bl). A stub is needed in this case.
+ if ((!thumb2
+ && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET
+ || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET)))
+ || (thumb2
+ && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET
+ || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET)))
+ || ((!target_is_thumb)
+ && (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
+ || (r_type == elfcpp::R_ARM_THM_JUMP24))))
+ {
+ if (target_is_thumb)
+ {
+ // Thumb to thumb.
+ if (!thumb_only)
+ {
+ stub_type = (parameters->options().shared()
+ || should_force_pic_veneer)
+ // PIC stubs.
+ ? ((may_use_blx
+ && (r_type == elfcpp::R_ARM_THM_CALL))
+ // V5T and above. Stub starts with ARM code, so
+ // we must be able to switch mode before
+ // reaching it, which is only possible for 'bl'
+ // (ie R_ARM_THM_CALL relocation).
+ ? arm_stub_long_branch_any_thumb_pic
+ // On V4T, use Thumb code only.
+ : arm_stub_long_branch_v4t_thumb_thumb_pic)
+
+ // non-PIC stubs.
+ : ((may_use_blx
+ && (r_type == elfcpp::R_ARM_THM_CALL))
+ ? arm_stub_long_branch_any_any // V5T and above.
+ : arm_stub_long_branch_v4t_thumb_thumb); // V4T.
+ }
+ else
+ {
+ stub_type = (parameters->options().shared()
+ || should_force_pic_veneer)
+ ? arm_stub_long_branch_thumb_only_pic // PIC stub.
+ : arm_stub_long_branch_thumb_only; // non-PIC stub.
+ }
+ }
+ else
+ {
+ // Thumb to arm.
+
+ // FIXME: We should check that the input section is from an
+ // object that has interwork enabled.
+
+ stub_type = (parameters->options().shared()
+ || should_force_pic_veneer)
+ // PIC stubs.
+ ? ((may_use_blx
+ && (r_type == elfcpp::R_ARM_THM_CALL))
+ ? arm_stub_long_branch_any_arm_pic // V5T and above.
+ : arm_stub_long_branch_v4t_thumb_arm_pic) // V4T.
+
+ // non-PIC stubs.
+ : ((may_use_blx
+ && (r_type == elfcpp::R_ARM_THM_CALL))
+ ? arm_stub_long_branch_any_any // V5T and above.
+ : arm_stub_long_branch_v4t_thumb_arm); // V4T.
+
+ // Handle v4t short branches.
+ if ((stub_type == arm_stub_long_branch_v4t_thumb_arm)
+ && (branch_offset <= THM_MAX_FWD_BRANCH_OFFSET)
+ && (branch_offset >= THM_MAX_BWD_BRANCH_OFFSET))
+ stub_type = arm_stub_short_branch_v4t_thumb_arm;
+ }
+ }
+ }
+ else if (r_type == elfcpp::R_ARM_CALL
+ || r_type == elfcpp::R_ARM_JUMP24
+ || r_type == elfcpp::R_ARM_PLT32)
+ {
+ branch_offset = static_cast<int64_t>(destination) - location;
+ if (target_is_thumb)
+ {
+ // Arm to thumb.
+
+ // FIXME: We should check that the input section is from an
+ // object that has interwork enabled.
+
+ // We have an extra 2-bytes reach because of
+ // the mode change (bit 24 (H) of BLX encoding).
+ if (branch_offset > (ARM_MAX_FWD_BRANCH_OFFSET + 2)
+ || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET)
+ || ((r_type == elfcpp::R_ARM_CALL) && !may_use_blx)
+ || (r_type == elfcpp::R_ARM_JUMP24)
+ || (r_type == elfcpp::R_ARM_PLT32))
+ {
stub_type = (parameters->options().shared()
|| should_force_pic_veneer)
// PIC stubs.
? arm_stub_long_branch_any_thumb_pic// V5T and above.
: arm_stub_long_branch_v4t_arm_thumb_pic) // V4T stub.
- // non-PIC stubs.
- : (may_use_blx
- ? arm_stub_long_branch_any_any // V5T and above.
- : arm_stub_long_branch_v4t_arm_thumb); // V4T.
- }
- }
- else
- {
- // Arm to arm.
- if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
- || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
- {
- stub_type = (parameters->options().shared()
- || should_force_pic_veneer)
- ? arm_stub_long_branch_any_arm_pic // PIC stubs.
- : arm_stub_long_branch_any_any; /// non-PIC.
- }
+ // non-PIC stubs.
+ : (may_use_blx
+ ? arm_stub_long_branch_any_any // V5T and above.
+ : arm_stub_long_branch_v4t_arm_thumb); // V4T.
+ }
+ }
+ else
+ {
+ // Arm to arm.
+ if (branch_offset > ARM_MAX_FWD_BRANCH_OFFSET
+ || (branch_offset < ARM_MAX_BWD_BRANCH_OFFSET))
+ {
+ stub_type = (parameters->options().shared()
+ || should_force_pic_veneer)
+ ? arm_stub_long_branch_any_arm_pic // PIC stubs.
+ : arm_stub_long_branch_any_any; /// non-PIC.
+ }
+ }
+ }
+
+ return stub_type;
+}
+
+// Cortex_a8_stub methods.
+
+// Return the instruction for a THUMB16_SPECIAL_TYPE instruction template.
+// I is the position of the instruction template in the stub template.
+
+uint16_t
+Cortex_a8_stub::do_thumb16_special(size_t i)
+{
+ // The only use of this is to copy condition code from a conditional
+ // branch being worked around to the corresponding conditional branch in
+ // to the stub.
+ gold_assert(this->stub_template()->type() == arm_stub_a8_veneer_b_cond
+ && i == 0);
+ uint16_t data = this->stub_template()->insns()[i].data();
+ gold_assert((data & 0xff00U) == 0xd000U);
+ data |= ((this->original_insn_ >> 22) & 0xf) << 8;
+ return data;
+}
+
+// Stub_factory methods.
+
+Stub_factory::Stub_factory()
+{
+ // The instruction template sequences are declared as static
+ // objects and initialized first time the constructor runs.
+
+ // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
+ // to reach the stub if necessary.
+ static const Insn_template elf32_arm_stub_long_branch_any_any[] =
+ {
+ Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
+ Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
+ // dcd R_ARM_ABS32(X)
+ };
+
+ // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
+ // available.
+ static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
+ {
+ Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
+ Insn_template::arm_insn(0xe12fff1c), // bx ip
+ Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
+ // dcd R_ARM_ABS32(X)
+ };
+
+ // Thumb -> Thumb long branch stub. Used on M-profile architectures.
+ static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
+ {
+ Insn_template::thumb16_insn(0xb401), // push {r0}
+ Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
+ Insn_template::thumb16_insn(0x4684), // mov ip, r0
+ Insn_template::thumb16_insn(0xbc01), // pop {r0}
+ Insn_template::thumb16_insn(0x4760), // bx ip
+ Insn_template::thumb16_insn(0xbf00), // nop
+ Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
+ // dcd R_ARM_ABS32(X)
+ };
+
+ // V4T Thumb -> Thumb long branch stub. Using the stack is not
+ // allowed.
+ static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
+ {
+ Insn_template::thumb16_insn(0x4778), // bx pc
+ Insn_template::thumb16_insn(0x46c0), // nop
+ Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
+ Insn_template::arm_insn(0xe12fff1c), // bx ip
+ Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
+ // dcd R_ARM_ABS32(X)
+ };
+
+ // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
+ // available.
+ static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
+ {
+ Insn_template::thumb16_insn(0x4778), // bx pc
+ Insn_template::thumb16_insn(0x46c0), // nop
+ Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
+ Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
+ // dcd R_ARM_ABS32(X)
+ };
+
+ // V4T Thumb -> ARM short branch stub. Shorter variant of the above
+ // one, when the destination is close enough.
+ static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
+ {
+ Insn_template::thumb16_insn(0x4778), // bx pc
+ Insn_template::thumb16_insn(0x46c0), // nop
+ Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
+ };
+
+ // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
+ // blx to reach the stub if necessary.
+ static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
+ {
+ Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
+ Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
+ Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
+ // dcd R_ARM_REL32(X-4)
+ };
+
+ // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
+ // blx to reach the stub if necessary. We can not add into pc;
+ // it is not guaranteed to mode switch (different in ARMv6 and
+ // ARMv7).
+ static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
+ {
+ Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
+ Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
+ Insn_template::arm_insn(0xe12fff1c), // bx ip
+ Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
+ // dcd R_ARM_REL32(X)
+ };
+
+ // V4T ARM -> ARM long branch stub, PIC.
+ static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
+ {
+ Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
+ Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
+ Insn_template::arm_insn(0xe12fff1c), // bx ip
+ Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
+ // dcd R_ARM_REL32(X)
+ };
+
+ // V4T Thumb -> ARM long branch stub, PIC.
+ static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
+ {
+ Insn_template::thumb16_insn(0x4778), // bx pc
+ Insn_template::thumb16_insn(0x46c0), // nop
+ Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
+ Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
+ Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
+ // dcd R_ARM_REL32(X)
+ };
+
+ // Thumb -> Thumb long branch stub, PIC. Used on M-profile
+ // architectures.
+ static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
+ {
+ Insn_template::thumb16_insn(0xb401), // push {r0}
+ Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
+ Insn_template::thumb16_insn(0x46fc), // mov ip, pc
+ Insn_template::thumb16_insn(0x4484), // add ip, r0
+ Insn_template::thumb16_insn(0xbc01), // pop {r0}
+ Insn_template::thumb16_insn(0x4760), // bx ip
+ Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
+ // dcd R_ARM_REL32(X)
+ };
+
+ // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
+ // allowed.
+ static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
+ {
+ Insn_template::thumb16_insn(0x4778), // bx pc
+ Insn_template::thumb16_insn(0x46c0), // nop
+ Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
+ Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
+ Insn_template::arm_insn(0xe12fff1c), // bx ip
+ Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
+ // dcd R_ARM_REL32(X)
+ };
+
+ // Cortex-A8 erratum-workaround stubs.
+
+ // Stub used for conditional branches (which may be beyond +/-1MB away,
+ // so we can't use a conditional branch to reach this stub).
+
+ // original code:
+ //
+ // b<cond> X
+ // after:
+ //
+ static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
+ {
+ Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
+ Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
+ Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
+ // b.w X
+ };
+
+ // Stub used for b.w and bl.w instructions.
+
+ static const Insn_template elf32_arm_stub_a8_veneer_b[] =
+ {
+ Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
+ };
+
+ static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
+ {
+ Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
+ };
+
+ // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
+ // instruction (which switches to ARM mode) to point to this stub. Jump to
+ // the real destination using an ARM-mode branch.
+ static const Insn_template elf32_arm_stub_a8_veneer_blx[] =
+ {
+ Insn_template::arm_rel_insn(0xea000000, -8) // b dest
+ };
+
+ // Stub used to provide an interworking for R_ARM_V4BX relocation
+ // (bx r[n] instruction).
+ static const Insn_template elf32_arm_stub_v4_veneer_bx[] =
+ {
+ Insn_template::arm_insn(0xe3100001), // tst r<n>, #1
+ Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n>
+ Insn_template::arm_insn(0xe12fff10) // bx r<n>
+ };
+
+ // Fill in the stub template look-up table. Stub templates are constructed
+ // per instance of Stub_factory for fast look-up without locking
+ // in a thread-enabled environment.
+
+ this->stub_templates_[arm_stub_none] =
+ new Stub_template(arm_stub_none, NULL, 0);
+
+#define DEF_STUB(x) \
+ do \
+ { \
+ size_t array_size \
+ = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
+ Stub_type type = arm_stub_##x; \
+ this->stub_templates_[type] = \
+ new Stub_template(type, elf32_arm_stub_##x, array_size); \
+ } \
+ while (0);
+
+ DEF_STUBS
+#undef DEF_STUB
+}
+
+// Stub_table methods.
+
+// Removel all Cortex-A8 stub.
+
+template<bool big_endian>
+void
+Stub_table<big_endian>::remove_all_cortex_a8_stubs()
+{
+ for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
+ p != this->cortex_a8_stubs_.end();
+ ++p)
+ delete p->second;
+ this->cortex_a8_stubs_.clear();
+}
+
+// Relocate one stub. This is a helper for Stub_table::relocate_stubs().
+
+template<bool big_endian>
+void
+Stub_table<big_endian>::relocate_stub(
+ Stub* stub,
+ const Relocate_info<32, big_endian>* relinfo,
+ Target_arm<big_endian>* arm_target,
+ Output_section* output_section,
+ unsigned char* view,
+ Arm_address address,
+ section_size_type view_size)
+{
+ const Stub_template* stub_template = stub->stub_template();
+ if (stub_template->reloc_count() != 0)
+ {
+ // Adjust view to cover the stub only.
+ section_size_type offset = stub->offset();
+ section_size_type stub_size = stub_template->size();
+ gold_assert(offset + stub_size <= view_size);
+
+ arm_target->relocate_stub(stub, relinfo, output_section, view + offset,
+ address + offset, stub_size);
+ }
+}
+
+// Relocate all stubs in this stub table.
+
+template<bool big_endian>
+void
+Stub_table<big_endian>::relocate_stubs(
+ const Relocate_info<32, big_endian>* relinfo,
+ Target_arm<big_endian>* arm_target,
+ Output_section* output_section,
+ unsigned char* view,
+ Arm_address address,
+ section_size_type view_size)
+{
+ // If we are passed a view bigger than the stub table's. we need to
+ // adjust the view.
+ gold_assert(address == this->address()
+ && (view_size
+ == static_cast<section_size_type>(this->data_size())));
+
+ // Relocate all relocation stubs.
+ for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
+ p != this->reloc_stubs_.end();
+ ++p)
+ this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
+ address, view_size);
+
+ // Relocate all Cortex-A8 stubs.
+ for (Cortex_a8_stub_list::iterator p = this->cortex_a8_stubs_.begin();
+ p != this->cortex_a8_stubs_.end();
+ ++p)
+ this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
+ address, view_size);
+
+ // Relocate all ARM V4BX stubs.
+ for (Arm_v4bx_stub_list::iterator p = this->arm_v4bx_stubs_.begin();
+ p != this->arm_v4bx_stubs_.end();
+ ++p)
+ {
+ if (*p != NULL)
+ this->relocate_stub(*p, relinfo, arm_target, output_section, view,
+ address, view_size);
+ }
+}
+
+// Write out the stubs to file.
+
+template<bool big_endian>
+void
+Stub_table<big_endian>::do_write(Output_file* of)
+{
+ off_t offset = this->offset();
+ const section_size_type oview_size =
+ convert_to_section_size_type(this->data_size());
+ unsigned char* const oview = of->get_output_view(offset, oview_size);
+
+ // Write relocation stubs.
+ for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
+ p != this->reloc_stubs_.end();
+ ++p)
+ {
+ Reloc_stub* stub = p->second;
+ Arm_address address = this->address() + stub->offset();
+ gold_assert(address
+ == align_address(address,
+ stub->stub_template()->alignment()));
+ stub->write(oview + stub->offset(), stub->stub_template()->size(),
+ big_endian);
+ }
+
+ // Write Cortex-A8 stubs.
+ for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
+ p != this->cortex_a8_stubs_.end();
+ ++p)
+ {
+ Cortex_a8_stub* stub = p->second;
+ Arm_address address = this->address() + stub->offset();
+ gold_assert(address
+ == align_address(address,
+ stub->stub_template()->alignment()));
+ stub->write(oview + stub->offset(), stub->stub_template()->size(),
+ big_endian);
+ }
+
+ // Write ARM V4BX relocation stubs.
+ for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
+ p != this->arm_v4bx_stubs_.end();
+ ++p)
+ {
+ if (*p == NULL)
+ continue;
+
+ Arm_address address = this->address() + (*p)->offset();
+ gold_assert(address
+ == align_address(address,
+ (*p)->stub_template()->alignment()));
+ (*p)->write(oview + (*p)->offset(), (*p)->stub_template()->size(),
+ big_endian);
+ }
+
+ of->write_output_view(this->offset(), oview_size, oview);
+}
+
+// Update the data size and address alignment of the stub table at the end
+// of a relaxation pass. Return true if either the data size or the
+// alignment changed in this relaxation pass.
+
+template<bool big_endian>
+bool
+Stub_table<big_endian>::update_data_size_and_addralign()
+{
+ // Go over all stubs in table to compute data size and address alignment.
+ off_t size = this->reloc_stubs_size_;
+ unsigned addralign = this->reloc_stubs_addralign_;
+
+ for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
+ p != this->cortex_a8_stubs_.end();
+ ++p)
+ {
+ const Stub_template* stub_template = p->second->stub_template();
+ addralign = std::max(addralign, stub_template->alignment());
+ size = (align_address(size, stub_template->alignment())
+ + stub_template->size());
+ }
+
+ for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
+ p != this->arm_v4bx_stubs_.end();
+ ++p)
+ {
+ if (*p == NULL)
+ continue;
+
+ const Stub_template* stub_template = (*p)->stub_template();
+ addralign = std::max(addralign, stub_template->alignment());
+ size = (align_address(size, stub_template->alignment())
+ + stub_template->size());
+ }
+
+ // Check if either data size or alignment changed in this pass.
+ // Update prev_data_size_ and prev_addralign_. These will be used
+ // as the current data size and address alignment for the next pass.
+ bool changed = size != this->prev_data_size_;
+ this->prev_data_size_ = size;
+
+ if (addralign != this->prev_addralign_)
+ changed = true;
+ this->prev_addralign_ = addralign;
+
+ return changed;
+}
+
+// Finalize the stubs. This sets the offsets of the stubs within the stub
+// table. It also marks all input sections needing Cortex-A8 workaround.
+
+template<bool big_endian>
+void
+Stub_table<big_endian>::finalize_stubs()
+{
+ off_t off = this->reloc_stubs_size_;
+ for (Cortex_a8_stub_list::const_iterator p = this->cortex_a8_stubs_.begin();
+ p != this->cortex_a8_stubs_.end();
+ ++p)
+ {
+ Cortex_a8_stub* stub = p->second;
+ const Stub_template* stub_template = stub->stub_template();
+ uint64_t stub_addralign = stub_template->alignment();
+ off = align_address(off, stub_addralign);
+ stub->set_offset(off);
+ off += stub_template->size();
+
+ // Mark input section so that we can determine later if a code section
+ // needs the Cortex-A8 workaround quickly.
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(stub->relobj());
+ arm_relobj->mark_section_for_cortex_a8_workaround(stub->shndx());
+ }
+
+ for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
+ p != this->arm_v4bx_stubs_.end();
+ ++p)
+ {
+ if (*p == NULL)
+ continue;
+
+ const Stub_template* stub_template = (*p)->stub_template();
+ uint64_t stub_addralign = stub_template->alignment();
+ off = align_address(off, stub_addralign);
+ (*p)->set_offset(off);
+ off += stub_template->size();
+ }
+
+ gold_assert(off <= this->prev_data_size_);
+}
+
+// Apply Cortex-A8 workaround to an address range between VIEW_ADDRESS
+// and VIEW_ADDRESS + VIEW_SIZE - 1. VIEW points to the mapped address
+// of the address range seen by the linker.
+
+template<bool big_endian>
+void
+Stub_table<big_endian>::apply_cortex_a8_workaround_to_address_range(
+ Target_arm<big_endian>* arm_target,
+ unsigned char* view,
+ Arm_address view_address,
+ section_size_type view_size)
+{
+ // Cortex-A8 stubs are sorted by addresses of branches being fixed up.
+ for (Cortex_a8_stub_list::const_iterator p =
+ this->cortex_a8_stubs_.lower_bound(view_address);
+ ((p != this->cortex_a8_stubs_.end())
+ && (p->first < (view_address + view_size)));
+ ++p)
+ {
+ // We do not store the THUMB bit in the LSB of either the branch address
+ // or the stub offset. There is no need to strip the LSB.
+ Arm_address branch_address = p->first;
+ const Cortex_a8_stub* stub = p->second;
+ Arm_address stub_address = this->address() + stub->offset();
+
+ // Offset of the branch instruction relative to this view.
+ section_size_type offset =
+ convert_to_section_size_type(branch_address - view_address);
+ gold_assert((offset + 4) <= view_size);
+
+ arm_target->apply_cortex_a8_workaround(stub, stub_address,
+ view + offset, branch_address);
+ }
+}
+
+// Arm_input_section methods.
+
+// Initialize an Arm_input_section.
+
+template<bool big_endian>
+void
+Arm_input_section<big_endian>::init()
+{
+ Relobj* relobj = this->relobj();
+ unsigned int shndx = this->shndx();
+
+ // Cache these to speed up size and alignment queries. It is too slow
+ // to call section_addraglin and section_size every time.
+ this->original_addralign_ =
+ convert_types<uint32_t, uint64_t>(relobj->section_addralign(shndx));
+ this->original_size_ =
+ convert_types<uint32_t, uint64_t>(relobj->section_size(shndx));
+
+ // We want to make this look like the original input section after
+ // output sections are finalized.
+ Output_section* os = relobj->output_section(shndx);
+ off_t offset = relobj->output_section_offset(shndx);
+ gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
+ this->set_address(os->address() + offset);
+ this->set_file_offset(os->offset() + offset);
+
+ this->set_current_data_size(this->original_size_);
+ this->finalize_data_size();
+}
+
+template<bool big_endian>
+void
+Arm_input_section<big_endian>::do_write(Output_file* of)
+{
+ // We have to write out the original section content.
+ section_size_type section_size;
+ const unsigned char* section_contents =
+ this->relobj()->section_contents(this->shndx(), §ion_size, false);
+ of->write(this->offset(), section_contents, section_size);
+
+ // If this owns a stub table and it is not empty, write it.
+ if (this->is_stub_table_owner() && !this->stub_table_->empty())
+ this->stub_table_->write(of);
+}
+
+// Finalize data size.
+
+template<bool big_endian>
+void
+Arm_input_section<big_endian>::set_final_data_size()
+{
+ off_t off = convert_types<off_t, uint64_t>(this->original_size_);
+
+ if (this->is_stub_table_owner())
+ {
+ this->stub_table_->finalize_data_size();
+ off = align_address(off, this->stub_table_->addralign());
+ off += this->stub_table_->data_size();
+ }
+ this->set_data_size(off);
+}
+
+// Reset address and file offset.
+
+template<bool big_endian>
+void
+Arm_input_section<big_endian>::do_reset_address_and_file_offset()
+{
+ // Size of the original input section contents.
+ off_t off = convert_types<off_t, uint64_t>(this->original_size_);
+
+ // If this is a stub table owner, account for the stub table size.
+ if (this->is_stub_table_owner())
+ {
+ Stub_table<big_endian>* stub_table = this->stub_table_;
+
+ // Reset the stub table's address and file offset. The
+ // current data size for child will be updated after that.
+ stub_table_->reset_address_and_file_offset();
+ off = align_address(off, stub_table_->addralign());
+ off += stub_table->current_data_size();
+ }
+
+ this->set_current_data_size(off);
+}
+
+// Arm_exidx_cantunwind methods.
+
+// Write this to Output file OF for a fixed endianness.
+
+template<bool big_endian>
+void
+Arm_exidx_cantunwind::do_fixed_endian_write(Output_file* of)
+{
+ off_t offset = this->offset();
+ const section_size_type oview_size = 8;
+ unsigned char* const oview = of->get_output_view(offset, oview_size);
+
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(oview);
+
+ Output_section* os = this->relobj_->output_section(this->shndx_);
+ gold_assert(os != NULL);
+
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(this->relobj_);
+ Arm_address output_offset =
+ arm_relobj->get_output_section_offset(this->shndx_);
+ Arm_address section_start;
+ if (output_offset != Arm_relobj<big_endian>::invalid_address)
+ section_start = os->address() + output_offset;
+ else
+ {
+ // Currently this only happens for a relaxed section.
+ const Output_relaxed_input_section* poris =
+ os->find_relaxed_input_section(this->relobj_, this->shndx_);
+ gold_assert(poris != NULL);
+ section_start = poris->address();
+ }
+
+ // We always append this to the end of an EXIDX section.
+ Arm_address output_address =
+ section_start + this->relobj_->section_size(this->shndx_);
+
+ // Write out the entry. The first word either points to the beginning
+ // or after the end of a text section. The second word is the special
+ // EXIDX_CANTUNWIND value.
+ uint32_t prel31_offset = output_address - this->address();
+ if (utils::has_overflow<31>(offset))
+ gold_error(_("PREL31 overflow in EXIDX_CANTUNWIND entry"));
+ elfcpp::Swap<32, big_endian>::writeval(wv, prel31_offset & 0x7fffffffU);
+ elfcpp::Swap<32, big_endian>::writeval(wv + 1, elfcpp::EXIDX_CANTUNWIND);
+
+ of->write_output_view(this->offset(), oview_size, oview);
+}
+
+// Arm_exidx_merged_section methods.
+
+// Constructor for Arm_exidx_merged_section.
+// EXIDX_INPUT_SECTION points to the unmodified EXIDX input section.
+// SECTION_OFFSET_MAP points to a section offset map describing how
+// parts of the input section are mapped to output. DELETED_BYTES is
+// the number of bytes deleted from the EXIDX input section.
+
+Arm_exidx_merged_section::Arm_exidx_merged_section(
+ const Arm_exidx_input_section& exidx_input_section,
+ const Arm_exidx_section_offset_map& section_offset_map,
+ uint32_t deleted_bytes)
+ : Output_relaxed_input_section(exidx_input_section.relobj(),
+ exidx_input_section.shndx(),
+ exidx_input_section.addralign()),
+ exidx_input_section_(exidx_input_section),
+ section_offset_map_(section_offset_map)
+{
+ // Fix size here so that we do not need to implement set_final_data_size.
+ this->set_data_size(exidx_input_section.size() - deleted_bytes);
+ this->fix_data_size();
+}
+
+// Given an input OBJECT, an input section index SHNDX within that
+// object, and an OFFSET relative to the start of that input
+// section, return whether or not the corresponding offset within
+// the output section is known. If this function returns true, it
+// sets *POUTPUT to the output offset. The value -1 indicates that
+// this input offset is being discarded.
+
+bool
+Arm_exidx_merged_section::do_output_offset(
+ const Relobj* relobj,
+ unsigned int shndx,
+ section_offset_type offset,
+ section_offset_type* poutput) const
+{
+ // We only handle offsets for the original EXIDX input section.
+ if (relobj != this->exidx_input_section_.relobj()
+ || shndx != this->exidx_input_section_.shndx())
+ return false;
+
+ section_offset_type section_size =
+ convert_types<section_offset_type>(this->exidx_input_section_.size());
+ if (offset < 0 || offset >= section_size)
+ // Input offset is out of valid range.
+ *poutput = -1;
+ else
+ {
+ // We need to look up the section offset map to determine the output
+ // offset. Find the reference point in map that is first offset
+ // bigger than or equal to this offset.
+ Arm_exidx_section_offset_map::const_iterator p =
+ this->section_offset_map_.lower_bound(offset);
+
+ // The section offset maps are build such that this should not happen if
+ // input offset is in the valid range.
+ gold_assert(p != this->section_offset_map_.end());
+
+ // We need to check if this is dropped.
+ section_offset_type ref = p->first;
+ section_offset_type mapped_ref = p->second;
+
+ if (mapped_ref != Arm_exidx_input_section::invalid_offset)
+ // Offset is present in output.
+ *poutput = mapped_ref + (offset - ref);
+ else
+ // Offset is discarded owing to EXIDX entry merging.
+ *poutput = -1;
+ }
+
+ return true;
+}
+
+// Write this to output file OF.
+
+void
+Arm_exidx_merged_section::do_write(Output_file* of)
+{
+ // If we retain or discard the whole EXIDX input section, we would
+ // not be here.
+ gold_assert(this->data_size() != this->exidx_input_section_.size()
+ && this->data_size() != 0);
+
+ off_t offset = this->offset();
+ const section_size_type oview_size = this->data_size();
+ unsigned char* const oview = of->get_output_view(offset, oview_size);
+
+ Output_section* os = this->relobj()->output_section(this->shndx());
+ gold_assert(os != NULL);
+
+ // Get contents of EXIDX input section.
+ section_size_type section_size;
+ const unsigned char* section_contents =
+ this->relobj()->section_contents(this->shndx(), §ion_size, false);
+ gold_assert(section_size == this->exidx_input_section_.size());
+
+ // Go over spans of input offsets and write only those that are not
+ // discarded.
+ section_offset_type in_start = 0;
+ section_offset_type out_start = 0;
+ for(Arm_exidx_section_offset_map::const_iterator p =
+ this->section_offset_map_.begin();
+ p != this->section_offset_map_.end();
+ ++p)
+ {
+ section_offset_type in_end = p->first;
+ gold_assert(in_end >= in_start);
+ section_offset_type out_end = p->second;
+ size_t in_chunk_size = convert_types<size_t>(in_end - in_start + 1);
+ if (out_end != -1)
+ {
+ size_t out_chunk_size =
+ convert_types<size_t>(out_end - out_start + 1);
+ gold_assert(out_chunk_size == in_chunk_size);
+ memcpy(oview + out_start, section_contents + in_start,
+ out_chunk_size);
+ out_start += out_chunk_size;
+ }
+ in_start += in_chunk_size;
+ }
+
+ gold_assert(convert_to_section_size_type(out_start) == oview_size);
+ of->write_output_view(this->offset(), oview_size, oview);
+}
+
+// Arm_exidx_fixup methods.
+
+// Append an EXIDX_CANTUNWIND in the current output section if the last entry
+// is not an EXIDX_CANTUNWIND entry already. The new EXIDX_CANTUNWIND entry
+// points to the end of the last seen EXIDX section.
+
+void
+Arm_exidx_fixup::add_exidx_cantunwind_as_needed()
+{
+ if (this->last_unwind_type_ != UT_EXIDX_CANTUNWIND
+ && this->last_input_section_ != NULL)
+ {
+ Relobj* relobj = this->last_input_section_->relobj();
+ unsigned int text_shndx = this->last_input_section_->link();
+ Arm_exidx_cantunwind* cantunwind =
+ new Arm_exidx_cantunwind(relobj, text_shndx);
+ this->exidx_output_section_->add_output_section_data(cantunwind);
+ this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
+ }
+}
+
+// Process an EXIDX section entry in input. Return whether this entry
+// can be deleted in the output. SECOND_WORD in the second word of the
+// EXIDX entry.
+
+bool
+Arm_exidx_fixup::process_exidx_entry(uint32_t second_word)
+{
+ bool delete_entry;
+ if (second_word == elfcpp::EXIDX_CANTUNWIND)
+ {
+ // Merge if previous entry is also an EXIDX_CANTUNWIND.
+ delete_entry = this->last_unwind_type_ == UT_EXIDX_CANTUNWIND;
+ this->last_unwind_type_ = UT_EXIDX_CANTUNWIND;
+ }
+ else if ((second_word & 0x80000000) != 0)
+ {
+ // Inlined unwinding data. Merge if equal to previous.
+ delete_entry = (merge_exidx_entries_
+ && this->last_unwind_type_ == UT_INLINED_ENTRY
+ && this->last_inlined_entry_ == second_word);
+ this->last_unwind_type_ = UT_INLINED_ENTRY;
+ this->last_inlined_entry_ = second_word;
+ }
+ else
+ {
+ // Normal table entry. In theory we could merge these too,
+ // but duplicate entries are likely to be much less common.
+ delete_entry = false;
+ this->last_unwind_type_ = UT_NORMAL_ENTRY;
+ }
+ return delete_entry;
+}
+
+// Update the current section offset map during EXIDX section fix-up.
+// If there is no map, create one. INPUT_OFFSET is the offset of a
+// reference point, DELETED_BYTES is the number of deleted by in the
+// section so far. If DELETE_ENTRY is true, the reference point and
+// all offsets after the previous reference point are discarded.
+
+void
+Arm_exidx_fixup::update_offset_map(
+ section_offset_type input_offset,
+ section_size_type deleted_bytes,
+ bool delete_entry)
+{
+ if (this->section_offset_map_ == NULL)
+ this->section_offset_map_ = new Arm_exidx_section_offset_map();
+ section_offset_type output_offset;
+ if (delete_entry)
+ output_offset = Arm_exidx_input_section::invalid_offset;
+ else
+ output_offset = input_offset - deleted_bytes;
+ (*this->section_offset_map_)[input_offset] = output_offset;
+}
+
+// Process EXIDX_INPUT_SECTION for EXIDX entry merging. Return the number of
+// bytes deleted. If some entries are merged, also store a pointer to a newly
+// created Arm_exidx_section_offset_map object in *PSECTION_OFFSET_MAP. The
+// caller owns the map and is responsible for releasing it after use.
+
+template<bool big_endian>
+uint32_t
+Arm_exidx_fixup::process_exidx_section(
+ const Arm_exidx_input_section* exidx_input_section,
+ Arm_exidx_section_offset_map** psection_offset_map)
+{
+ Relobj* relobj = exidx_input_section->relobj();
+ unsigned shndx = exidx_input_section->shndx();
+ section_size_type section_size;
+ const unsigned char* section_contents =
+ relobj->section_contents(shndx, §ion_size, false);
+
+ if ((section_size % 8) != 0)
+ {
+ // Something is wrong with this section. Better not touch it.
+ gold_error(_("uneven .ARM.exidx section size in %s section %u"),
+ relobj->name().c_str(), shndx);
+ this->last_input_section_ = exidx_input_section;
+ this->last_unwind_type_ = UT_NONE;
+ return 0;
+ }
+
+ uint32_t deleted_bytes = 0;
+ bool prev_delete_entry = false;
+ gold_assert(this->section_offset_map_ == NULL);
+
+ for (section_size_type i = 0; i < section_size; i += 8)
+ {
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ const Valtype* wv =
+ reinterpret_cast<const Valtype*>(section_contents + i + 4);
+ uint32_t second_word = elfcpp::Swap<32, big_endian>::readval(wv);
+
+ bool delete_entry = this->process_exidx_entry(second_word);
+
+ // Entry deletion causes changes in output offsets. We use a std::map
+ // to record these. And entry (x, y) means input offset x
+ // is mapped to output offset y. If y is invalid_offset, then x is
+ // dropped in the output. Because of the way std::map::lower_bound
+ // works, we record the last offset in a region w.r.t to keeping or
+ // dropping. If there is no entry (x0, y0) for an input offset x0,
+ // the output offset y0 of it is determined by the output offset y1 of
+ // the smallest input offset x1 > x0 that there is an (x1, y1) entry
+ // in the map. If y1 is not -1, then y0 = y1 + x0 - x1. Othewise, y1
+ // y0 is also -1.
+ if (delete_entry != prev_delete_entry && i != 0)
+ this->update_offset_map(i - 1, deleted_bytes, prev_delete_entry);
+
+ // Update total deleted bytes for this entry.
+ if (delete_entry)
+ deleted_bytes += 8;
+
+ prev_delete_entry = delete_entry;
+ }
+
+ // If section offset map is not NULL, make an entry for the end of
+ // section.
+ if (this->section_offset_map_ != NULL)
+ update_offset_map(section_size - 1, deleted_bytes, prev_delete_entry);
+
+ *psection_offset_map = this->section_offset_map_;
+ this->section_offset_map_ = NULL;
+ this->last_input_section_ = exidx_input_section;
+
+ // Set the first output text section so that we can link the EXIDX output
+ // section to it. Ignore any EXIDX input section that is completely merged.
+ if (this->first_output_text_section_ == NULL
+ && deleted_bytes != section_size)
+ {
+ unsigned int link = exidx_input_section->link();
+ Output_section* os = relobj->output_section(link);
+ gold_assert(os != NULL);
+ this->first_output_text_section_ = os;
+ }
+
+ return deleted_bytes;
+}
+
+// Arm_output_section methods.
+
+// Create a stub group for input sections from BEGIN to END. OWNER
+// points to the input section to be the owner a new stub table.
+
+template<bool big_endian>
+void
+Arm_output_section<big_endian>::create_stub_group(
+ Input_section_list::const_iterator begin,
+ Input_section_list::const_iterator end,
+ Input_section_list::const_iterator owner,
+ Target_arm<big_endian>* target,
+ std::vector<Output_relaxed_input_section*>* new_relaxed_sections)
+{
+ // We use a different kind of relaxed section in an EXIDX section.
+ // The static casting from Output_relaxed_input_section to
+ // Arm_input_section is invalid in an EXIDX section. We are okay
+ // because we should not be calling this for an EXIDX section.
+ gold_assert(this->type() != elfcpp::SHT_ARM_EXIDX);
+
+ // Currently we convert ordinary input sections into relaxed sections only
+ // at this point but we may want to support creating relaxed input section
+ // very early. So we check here to see if owner is already a relaxed
+ // section.
+
+ Arm_input_section<big_endian>* arm_input_section;
+ if (owner->is_relaxed_input_section())
+ {
+ arm_input_section =
+ Arm_input_section<big_endian>::as_arm_input_section(
+ owner->relaxed_input_section());
+ }
+ else
+ {
+ gold_assert(owner->is_input_section());
+ // Create a new relaxed input section.
+ arm_input_section =
+ target->new_arm_input_section(owner->relobj(), owner->shndx());
+ new_relaxed_sections->push_back(arm_input_section);
+ }
+
+ // Create a stub table.
+ Stub_table<big_endian>* stub_table =
+ target->new_stub_table(arm_input_section);
+
+ arm_input_section->set_stub_table(stub_table);
+
+ Input_section_list::const_iterator p = begin;
+ Input_section_list::const_iterator prev_p;
+
+ // Look for input sections or relaxed input sections in [begin ... end].
+ do
+ {
+ if (p->is_input_section() || p->is_relaxed_input_section())
+ {
+ // The stub table information for input sections live
+ // in their objects.
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
+ arm_relobj->set_stub_table(p->shndx(), stub_table);
+ }
+ prev_p = p++;
+ }
+ while (prev_p != end);
+}
+
+// Group input sections for stub generation. GROUP_SIZE is roughly the limit
+// of stub groups. We grow a stub group by adding input section until the
+// size is just below GROUP_SIZE. The last input section will be converted
+// into a stub table. If STUB_ALWAYS_AFTER_BRANCH is false, we also add
+// input section after the stub table, effectively double the group size.
+//
+// This is similar to the group_sections() function in elf32-arm.c but is
+// implemented differently.
+
+template<bool big_endian>
+void
+Arm_output_section<big_endian>::group_sections(
+ section_size_type group_size,
+ bool stubs_always_after_branch,
+ Target_arm<big_endian>* target)
+{
+ // We only care about sections containing code.
+ if ((this->flags() & elfcpp::SHF_EXECINSTR) == 0)
+ return;
+
+ // States for grouping.
+ typedef enum
+ {
+ // No group is being built.
+ NO_GROUP,
+ // A group is being built but the stub table is not found yet.
+ // We keep group a stub group until the size is just under GROUP_SIZE.
+ // The last input section in the group will be used as the stub table.
+ FINDING_STUB_SECTION,
+ // A group is being built and we have already found a stub table.
+ // We enter this state to grow a stub group by adding input section
+ // after the stub table. This effectively doubles the group size.
+ HAS_STUB_SECTION
+ } State;
+
+ // Any newly created relaxed sections are stored here.
+ std::vector<Output_relaxed_input_section*> new_relaxed_sections;
+
+ State state = NO_GROUP;
+ section_size_type off = 0;
+ section_size_type group_begin_offset = 0;
+ section_size_type group_end_offset = 0;
+ section_size_type stub_table_end_offset = 0;
+ Input_section_list::const_iterator group_begin =
+ this->input_sections().end();
+ Input_section_list::const_iterator stub_table =
+ this->input_sections().end();
+ Input_section_list::const_iterator group_end = this->input_sections().end();
+ for (Input_section_list::const_iterator p = this->input_sections().begin();
+ p != this->input_sections().end();
+ ++p)
+ {
+ section_size_type section_begin_offset =
+ align_address(off, p->addralign());
+ section_size_type section_end_offset =
+ section_begin_offset + p->data_size();
+
+ // Check to see if we should group the previously seens sections.
+ switch (state)
+ {
+ case NO_GROUP:
+ break;
+
+ case FINDING_STUB_SECTION:
+ // Adding this section makes the group larger than GROUP_SIZE.
+ if (section_end_offset - group_begin_offset >= group_size)
+ {
+ if (stubs_always_after_branch)
+ {
+ gold_assert(group_end != this->input_sections().end());
+ this->create_stub_group(group_begin, group_end, group_end,
+ target, &new_relaxed_sections);
+ state = NO_GROUP;
+ }
+ else
+ {
+ // But wait, there's more! Input sections up to
+ // stub_group_size bytes after the stub table can be
+ // handled by it too.
+ state = HAS_STUB_SECTION;
+ stub_table = group_end;
+ stub_table_end_offset = group_end_offset;
+ }
+ }
+ break;
+
+ case HAS_STUB_SECTION:
+ // Adding this section makes the post stub-section group larger
+ // than GROUP_SIZE.
+ if (section_end_offset - stub_table_end_offset >= group_size)
+ {
+ gold_assert(group_end != this->input_sections().end());
+ this->create_stub_group(group_begin, group_end, stub_table,
+ target, &new_relaxed_sections);
+ state = NO_GROUP;
+ }
+ break;
+
+ default:
+ gold_unreachable();
+ }
+
+ // If we see an input section and currently there is no group, start
+ // a new one. Skip any empty sections.
+ if ((p->is_input_section() || p->is_relaxed_input_section())
+ && (p->relobj()->section_size(p->shndx()) != 0))
+ {
+ if (state == NO_GROUP)
+ {
+ state = FINDING_STUB_SECTION;
+ group_begin = p;
+ group_begin_offset = section_begin_offset;
+ }
+
+ // Keep track of the last input section seen.
+ group_end = p;
+ group_end_offset = section_end_offset;
+ }
+
+ off = section_end_offset;
+ }
+
+ // Create a stub group for any ungrouped sections.
+ if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
+ {
+ gold_assert(group_end != this->input_sections().end());
+ this->create_stub_group(group_begin, group_end,
+ (state == FINDING_STUB_SECTION
+ ? group_end
+ : stub_table),
+ target, &new_relaxed_sections);
+ }
+
+ // Convert input section into relaxed input section in a batch.
+ if (!new_relaxed_sections.empty())
+ this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
+
+ // Update the section offsets
+ for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
+ {
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(
+ new_relaxed_sections[i]->relobj());
+ unsigned int shndx = new_relaxed_sections[i]->shndx();
+ // Tell Arm_relobj that this input section is converted.
+ arm_relobj->convert_input_section_to_relaxed_section(shndx);
+ }
+}
+
+// Append non empty text sections in this to LIST in ascending
+// order of their position in this.
+
+template<bool big_endian>
+void
+Arm_output_section<big_endian>::append_text_sections_to_list(
+ Text_section_list* list)
+{
+ gold_assert((this->flags() & elfcpp::SHF_ALLOC) != 0);
+
+ for (Input_section_list::const_iterator p = this->input_sections().begin();
+ p != this->input_sections().end();
+ ++p)
+ {
+ // We only care about plain or relaxed input sections. We also
+ // ignore any merged sections.
+ if ((p->is_input_section() || p->is_relaxed_input_section())
+ && p->data_size() != 0)
+ list->push_back(Text_section_list::value_type(p->relobj(),
+ p->shndx()));
+ }
+}
+
+template<bool big_endian>
+void
+Arm_output_section<big_endian>::fix_exidx_coverage(
+ Layout* layout,
+ const Text_section_list& sorted_text_sections,
+ Symbol_table* symtab,
+ bool merge_exidx_entries)
+{
+ // We should only do this for the EXIDX output section.
+ gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
+
+ // We don't want the relaxation loop to undo these changes, so we discard
+ // the current saved states and take another one after the fix-up.
+ this->discard_states();
+
+ // Remove all input sections.
+ uint64_t address = this->address();
+ typedef std::list<Output_section::Input_section> Input_section_list;
+ Input_section_list input_sections;
+ this->reset_address_and_file_offset();
+ this->get_input_sections(address, std::string(""), &input_sections);
+
+ if (!this->input_sections().empty())
+ gold_error(_("Found non-EXIDX input sections in EXIDX output section"));
+
+ // Go through all the known input sections and record them.
+ typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
+ typedef Unordered_map<Section_id, const Output_section::Input_section*,
+ Section_id_hash> Text_to_exidx_map;
+ Text_to_exidx_map text_to_exidx_map;
+ for (Input_section_list::const_iterator p = input_sections.begin();
+ p != input_sections.end();
+ ++p)
+ {
+ // This should never happen. At this point, we should only see
+ // plain EXIDX input sections.
+ gold_assert(!p->is_relaxed_input_section());
+ text_to_exidx_map[Section_id(p->relobj(), p->shndx())] = &(*p);
+ }
+
+ Arm_exidx_fixup exidx_fixup(this, merge_exidx_entries);
+
+ // Go over the sorted text sections.
+ typedef Unordered_set<Section_id, Section_id_hash> Section_id_set;
+ Section_id_set processed_input_sections;
+ for (Text_section_list::const_iterator p = sorted_text_sections.begin();
+ p != sorted_text_sections.end();
+ ++p)
+ {
+ Relobj* relobj = p->first;
+ unsigned int shndx = p->second;
+
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(relobj);
+ const Arm_exidx_input_section* exidx_input_section =
+ arm_relobj->exidx_input_section_by_link(shndx);
+
+ // If this text section has no EXIDX section or if the EXIDX section
+ // has errors, force an EXIDX_CANTUNWIND entry pointing to the end
+ // of the last seen EXIDX section.
+ if (exidx_input_section == NULL || exidx_input_section->has_errors())
+ {
+ exidx_fixup.add_exidx_cantunwind_as_needed();
+ continue;
+ }
+
+ Relobj* exidx_relobj = exidx_input_section->relobj();
+ unsigned int exidx_shndx = exidx_input_section->shndx();
+ Section_id sid(exidx_relobj, exidx_shndx);
+ Text_to_exidx_map::const_iterator iter = text_to_exidx_map.find(sid);
+ if (iter == text_to_exidx_map.end())
+ {
+ // This is odd. We have not seen this EXIDX input section before.
+ // We cannot do fix-up. If we saw a SECTIONS clause in a script,
+ // issue a warning instead. We assume the user knows what he
+ // or she is doing. Otherwise, this is an error.
+ if (layout->script_options()->saw_sections_clause())
+ gold_warning(_("unwinding may not work because EXIDX input section"
+ " %u of %s is not in EXIDX output section"),
+ exidx_shndx, exidx_relobj->name().c_str());
+ else
+ gold_error(_("unwinding may not work because EXIDX input section"
+ " %u of %s is not in EXIDX output section"),
+ exidx_shndx, exidx_relobj->name().c_str());
+
+ exidx_fixup.add_exidx_cantunwind_as_needed();
+ continue;
+ }
+
+ // Fix up coverage and append input section to output data list.
+ Arm_exidx_section_offset_map* section_offset_map = NULL;
+ uint32_t deleted_bytes =
+ exidx_fixup.process_exidx_section<big_endian>(exidx_input_section,
+ §ion_offset_map);
+
+ if (deleted_bytes == exidx_input_section->size())
+ {
+ // The whole EXIDX section got merged. Remove it from output.
+ gold_assert(section_offset_map == NULL);
+ exidx_relobj->set_output_section(exidx_shndx, NULL);
+
+ // All local symbols defined in this input section will be dropped.
+ // We need to adjust output local symbol count.
+ arm_relobj->set_output_local_symbol_count_needs_update();
+ }
+ else if (deleted_bytes > 0)
+ {
+ // Some entries are merged. We need to convert this EXIDX input
+ // section into a relaxed section.
+ gold_assert(section_offset_map != NULL);
+ Arm_exidx_merged_section* merged_section =
+ new Arm_exidx_merged_section(*exidx_input_section,
+ *section_offset_map, deleted_bytes);
+ this->add_relaxed_input_section(merged_section);
+ arm_relobj->convert_input_section_to_relaxed_section(exidx_shndx);
+
+ // All local symbols defined in discarded portions of this input
+ // section will be dropped. We need to adjust output local symbol
+ // count.
+ arm_relobj->set_output_local_symbol_count_needs_update();
+ }
+ else
+ {
+ // Just add back the EXIDX input section.
+ gold_assert(section_offset_map == NULL);
+ const Output_section::Input_section* pis = iter->second;
+ gold_assert(pis->is_input_section());
+ this->add_script_input_section(*pis);
+ }
+
+ processed_input_sections.insert(Section_id(exidx_relobj, exidx_shndx));
+ }
+
+ // Insert an EXIDX_CANTUNWIND entry at the end of output if necessary.
+ exidx_fixup.add_exidx_cantunwind_as_needed();
+
+ // Remove any known EXIDX input sections that are not processed.
+ for (Input_section_list::const_iterator p = input_sections.begin();
+ p != input_sections.end();
+ ++p)
+ {
+ if (processed_input_sections.find(Section_id(p->relobj(), p->shndx()))
+ == processed_input_sections.end())
+ {
+ // We discard a known EXIDX section because its linked
+ // text section has been folded by ICF. We also discard an
+ // EXIDX section with error, the output does not matter in this
+ // case. We do this to avoid triggering asserts.
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
+ const Arm_exidx_input_section* exidx_input_section =
+ arm_relobj->exidx_input_section_by_shndx(p->shndx());
+ gold_assert(exidx_input_section != NULL);
+ if (!exidx_input_section->has_errors())
+ {
+ unsigned int text_shndx = exidx_input_section->link();
+ gold_assert(symtab->is_section_folded(p->relobj(), text_shndx));
+ }
+
+ // Remove this from link. We also need to recount the
+ // local symbols.
+ p->relobj()->set_output_section(p->shndx(), NULL);
+ arm_relobj->set_output_local_symbol_count_needs_update();
+ }
+ }
+
+ // Link exidx output section to the first seen output section and
+ // set correct entry size.
+ this->set_link_section(exidx_fixup.first_output_text_section());
+ this->set_entsize(8);
+
+ // Make changes permanent.
+ this->save_states();
+ this->set_section_offsets_need_adjustment();
+}
+
+// Link EXIDX output sections to text output sections.
+
+template<bool big_endian>
+void
+Arm_output_section<big_endian>::set_exidx_section_link()
+{
+ gold_assert(this->type() == elfcpp::SHT_ARM_EXIDX);
+ if (!this->input_sections().empty())
+ {
+ Input_section_list::const_iterator p = this->input_sections().begin();
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(p->relobj());
+ unsigned exidx_shndx = p->shndx();
+ const Arm_exidx_input_section* exidx_input_section =
+ arm_relobj->exidx_input_section_by_shndx(exidx_shndx);
+ gold_assert(exidx_input_section != NULL);
+ unsigned int text_shndx = exidx_input_section->link();
+ Output_section* os = arm_relobj->output_section(text_shndx);
+ this->set_link_section(os);
+ }
+}
+
+// Arm_relobj methods.
+
+// Determine if an input section is scannable for stub processing. SHDR is
+// the header of the section and SHNDX is the section index. OS is the output
+// section for the input section and SYMTAB is the global symbol table used to
+// look up ICF information.
+
+template<bool big_endian>
+bool
+Arm_relobj<big_endian>::section_is_scannable(
+ const elfcpp::Shdr<32, big_endian>& shdr,
+ unsigned int shndx,
+ const Output_section* os,
+ const Symbol_table *symtab)
+{
+ // Skip any empty sections, unallocated sections or sections whose
+ // type are not SHT_PROGBITS.
+ if (shdr.get_sh_size() == 0
+ || (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
+ || shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
+ return false;
+
+ // Skip any discarded or ICF'ed sections.
+ if (os == NULL || symtab->is_section_folded(this, shndx))
+ return false;
+
+ // If this requires special offset handling, check to see if it is
+ // a relaxed section. If this is not, then it is a merged section that
+ // we cannot handle.
+ if (this->is_output_section_offset_invalid(shndx))
+ {
+ const Output_relaxed_input_section* poris =
+ os->find_relaxed_input_section(this, shndx);
+ if (poris == NULL)
+ return false;
+ }
+
+ return true;
+}
+
+// Determine if we want to scan the SHNDX-th section for relocation stubs.
+// This is a helper for Arm_relobj::scan_sections_for_stubs() below.
+
+template<bool big_endian>
+bool
+Arm_relobj<big_endian>::section_needs_reloc_stub_scanning(
+ const elfcpp::Shdr<32, big_endian>& shdr,
+ const Relobj::Output_sections& out_sections,
+ const Symbol_table *symtab,
+ const unsigned char* pshdrs)
+{
+ unsigned int sh_type = shdr.get_sh_type();
+ if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
+ return false;
+
+ // Ignore empty section.
+ off_t sh_size = shdr.get_sh_size();
+ if (sh_size == 0)
+ return false;
+
+ // Ignore reloc section with unexpected symbol table. The
+ // error will be reported in the final link.
+ if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
+ return false;
+
+ unsigned int reloc_size;
+ if (sh_type == elfcpp::SHT_REL)
+ reloc_size = elfcpp::Elf_sizes<32>::rel_size;
+ else
+ reloc_size = elfcpp::Elf_sizes<32>::rela_size;
+
+ // Ignore reloc section with unexpected entsize or uneven size.
+ // The error will be reported in the final link.
+ if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
+ return false;
+
+ // Ignore reloc section with bad info. This error will be
+ // reported in the final link.
+ unsigned int index = this->adjust_shndx(shdr.get_sh_info());
+ if (index >= this->shnum())
+ return false;
+
+ const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
+ const elfcpp::Shdr<32, big_endian> text_shdr(pshdrs + index * shdr_size);
+ return this->section_is_scannable(text_shdr, index,
+ out_sections[index], symtab);
+}
+
+// Return the output address of either a plain input section or a relaxed
+// input section. SHNDX is the section index. We define and use this
+// instead of calling Output_section::output_address because that is slow
+// for large output.
+
+template<bool big_endian>
+Arm_address
+Arm_relobj<big_endian>::simple_input_section_output_address(
+ unsigned int shndx,
+ Output_section* os)
+{
+ if (this->is_output_section_offset_invalid(shndx))
+ {
+ const Output_relaxed_input_section* poris =
+ os->find_relaxed_input_section(this, shndx);
+ // We do not handle merged sections here.
+ gold_assert(poris != NULL);
+ return poris->address();
+ }
+ else
+ return os->address() + this->get_output_section_offset(shndx);
+}
+
+// Determine if we want to scan the SHNDX-th section for non-relocation stubs.
+// This is a helper for Arm_relobj::scan_sections_for_stubs() below.
+
+template<bool big_endian>
+bool
+Arm_relobj<big_endian>::section_needs_cortex_a8_stub_scanning(
+ const elfcpp::Shdr<32, big_endian>& shdr,
+ unsigned int shndx,
+ Output_section* os,
+ const Symbol_table* symtab)
+{
+ if (!this->section_is_scannable(shdr, shndx, os, symtab))
+ return false;
+
+ // If the section does not cross any 4K-boundaries, it does not need to
+ // be scanned.
+ Arm_address address = this->simple_input_section_output_address(shndx, os);
+ if ((address & ~0xfffU) == ((address + shdr.get_sh_size() - 1) & ~0xfffU))
+ return false;
+
+ return true;
+}
+
+// Scan a section for Cortex-A8 workaround.
+
+template<bool big_endian>
+void
+Arm_relobj<big_endian>::scan_section_for_cortex_a8_erratum(
+ const elfcpp::Shdr<32, big_endian>& shdr,
+ unsigned int shndx,
+ Output_section* os,
+ Target_arm<big_endian>* arm_target)
+{
+ // Look for the first mapping symbol in this section. It should be
+ // at (shndx, 0).
+ Mapping_symbol_position section_start(shndx, 0);
+ typename Mapping_symbols_info::const_iterator p =
+ this->mapping_symbols_info_.lower_bound(section_start);
+
+ // There are no mapping symbols for this section. Treat it as a data-only
+ // section. Issue a warning if section is marked as containing
+ // instructions.
+ if (p == this->mapping_symbols_info_.end() || p->first.first != shndx)
+ {
+ if ((this->section_flags(shndx) & elfcpp::SHF_EXECINSTR) != 0)
+ gold_warning(_("cannot scan executable section %u of %s for Cortex-A8 "
+ "erratum because it has no mapping symbols."),
+ shndx, this->name().c_str());
+ return;
+ }
+
+ Arm_address output_address =
+ this->simple_input_section_output_address(shndx, os);
+
+ // Get the section contents.
+ section_size_type input_view_size = 0;
+ const unsigned char* input_view =
+ this->section_contents(shndx, &input_view_size, false);
+
+ // We need to go through the mapping symbols to determine what to
+ // scan. There are two reasons. First, we should look at THUMB code and
+ // THUMB code only. Second, we only want to look at the 4K-page boundary
+ // to speed up the scanning.
+
+ while (p != this->mapping_symbols_info_.end()
+ && p->first.first == shndx)
+ {
+ typename Mapping_symbols_info::const_iterator next =
+ this->mapping_symbols_info_.upper_bound(p->first);
+
+ // Only scan part of a section with THUMB code.
+ if (p->second == 't')
+ {
+ // Determine the end of this range.
+ section_size_type span_start =
+ convert_to_section_size_type(p->first.second);
+ section_size_type span_end;
+ if (next != this->mapping_symbols_info_.end()
+ && next->first.first == shndx)
+ span_end = convert_to_section_size_type(next->first.second);
+ else
+ span_end = convert_to_section_size_type(shdr.get_sh_size());
+
+ if (((span_start + output_address) & ~0xfffUL)
+ != ((span_end + output_address - 1) & ~0xfffUL))
+ {
+ arm_target->scan_span_for_cortex_a8_erratum(this, shndx,
+ span_start, span_end,
+ input_view,
+ output_address);
+ }
+ }
+
+ p = next;
+ }
+}
+
+// Scan relocations for stub generation.
+
+template<bool big_endian>
+void
+Arm_relobj<big_endian>::scan_sections_for_stubs(
+ Target_arm<big_endian>* arm_target,
+ const Symbol_table* symtab,
+ const Layout* layout)
+{
+ unsigned int shnum = this->shnum();
+ const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
+
+ // Read the section headers.
+ const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
+ shnum * shdr_size,
+ true, true);
+
+ // To speed up processing, we set up hash tables for fast lookup of
+ // input offsets to output addresses.
+ this->initialize_input_to_output_maps();
+
+ const Relobj::Output_sections& out_sections(this->output_sections());
+
+ Relocate_info<32, big_endian> relinfo;
+ relinfo.symtab = symtab;
+ relinfo.layout = layout;
+ relinfo.object = this;
+
+ // Do relocation stubs scanning.
+ const unsigned char* p = pshdrs + shdr_size;
+ for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
+ {
+ const elfcpp::Shdr<32, big_endian> shdr(p);
+ if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
+ pshdrs))
+ {
+ unsigned int index = this->adjust_shndx(shdr.get_sh_info());
+ Arm_address output_offset = this->get_output_section_offset(index);
+ Arm_address output_address;
+ if (output_offset != invalid_address)
+ output_address = out_sections[index]->address() + output_offset;
+ else
+ {
+ // Currently this only happens for a relaxed section.
+ const Output_relaxed_input_section* poris =
+ out_sections[index]->find_relaxed_input_section(this, index);
+ gold_assert(poris != NULL);
+ output_address = poris->address();
+ }
+
+ // Get the relocations.
+ const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
+ shdr.get_sh_size(),
+ true, false);
+
+ // Get the section contents. This does work for the case in which
+ // we modify the contents of an input section. We need to pass the
+ // output view under such circumstances.
+ section_size_type input_view_size = 0;
+ const unsigned char* input_view =
+ this->section_contents(index, &input_view_size, false);
+
+ relinfo.reloc_shndx = i;
+ relinfo.data_shndx = index;
+ unsigned int sh_type = shdr.get_sh_type();
+ unsigned int reloc_size;
+ if (sh_type == elfcpp::SHT_REL)
+ reloc_size = elfcpp::Elf_sizes<32>::rel_size;
+ else
+ reloc_size = elfcpp::Elf_sizes<32>::rela_size;
+
+ Output_section* os = out_sections[index];
+ arm_target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
+ shdr.get_sh_size() / reloc_size,
+ os,
+ output_offset == invalid_address,
+ input_view, output_address,
+ input_view_size);
+ }
+ }
+
+ // Do Cortex-A8 erratum stubs scanning. This has to be done for a section
+ // after its relocation section, if there is one, is processed for
+ // relocation stubs. Merging this loop with the one above would have been
+ // complicated since we would have had to make sure that relocation stub
+ // scanning is done first.
+ if (arm_target->fix_cortex_a8())
+ {
+ const unsigned char* p = pshdrs + shdr_size;
+ for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
+ {
+ const elfcpp::Shdr<32, big_endian> shdr(p);
+ if (this->section_needs_cortex_a8_stub_scanning(shdr, i,
+ out_sections[i],
+ symtab))
+ this->scan_section_for_cortex_a8_erratum(shdr, i, out_sections[i],
+ arm_target);
+ }
+ }
+
+ // After we've done the relocations, we release the hash tables,
+ // since we no longer need them.
+ this->free_input_to_output_maps();
+}
+
+// Count the local symbols. The ARM backend needs to know if a symbol
+// is a THUMB function or not. For global symbols, it is easy because
+// the Symbol object keeps the ELF symbol type. For local symbol it is
+// harder because we cannot access this information. So we override the
+// do_count_local_symbol in parent and scan local symbols to mark
+// THUMB functions. This is not the most efficient way but I do not want to
+// slow down other ports by calling a per symbol targer hook inside
+// Sized_relobj<size, big_endian>::do_count_local_symbols.
+
+template<bool big_endian>
+void
+Arm_relobj<big_endian>::do_count_local_symbols(
+ Stringpool_template<char>* pool,
+ Stringpool_template<char>* dynpool)
+{
+ // We need to fix-up the values of any local symbols whose type are
+ // STT_ARM_TFUNC.
+
+ // Ask parent to count the local symbols.
+ Sized_relobj<32, big_endian>::do_count_local_symbols(pool, dynpool);
+ const unsigned int loccount = this->local_symbol_count();
+ if (loccount == 0)
+ return;
+
+ // Intialize the thumb function bit-vector.
+ std::vector<bool> empty_vector(loccount, false);
+ this->local_symbol_is_thumb_function_.swap(empty_vector);
+
+ // Read the symbol table section header.
+ const unsigned int symtab_shndx = this->symtab_shndx();
+ elfcpp::Shdr<32, big_endian>
+ symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
+ gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
+
+ // Read the local symbols.
+ const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
+ gold_assert(loccount == symtabshdr.get_sh_info());
+ off_t locsize = loccount * sym_size;
+ const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
+ locsize, true, true);
+
+ // For mapping symbol processing, we need to read the symbol names.
+ unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
+ if (strtab_shndx >= this->shnum())
+ {
+ this->error(_("invalid symbol table name index: %u"), strtab_shndx);
+ return;
+ }
+
+ elfcpp::Shdr<32, big_endian>
+ strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
+ if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
+ {
+ this->error(_("symbol table name section has wrong type: %u"),
+ static_cast<unsigned int>(strtabshdr.get_sh_type()));
+ return;
+ }
+ const char* pnames =
+ reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
+ strtabshdr.get_sh_size(),
+ false, false));
+
+ // Loop over the local symbols and mark any local symbols pointing
+ // to THUMB functions.
+
+ // Skip the first dummy symbol.
+ psyms += sym_size;
+ typename Sized_relobj<32, big_endian>::Local_values* plocal_values =
+ this->local_values();
+ for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
+ {
+ elfcpp::Sym<32, big_endian> sym(psyms);
+ elfcpp::STT st_type = sym.get_st_type();
+ Symbol_value<32>& lv((*plocal_values)[i]);
+ Arm_address input_value = lv.input_value();
+
+ // Check to see if this is a mapping symbol.
+ const char* sym_name = pnames + sym.get_st_name();
+ if (Target_arm<big_endian>::is_mapping_symbol_name(sym_name))
+ {
+ bool is_ordinary;
+ unsigned int input_shndx =
+ this->adjust_sym_shndx(i, sym.get_st_shndx(), &is_ordinary);
+ gold_assert(is_ordinary);
+
+ // Strip of LSB in case this is a THUMB symbol.
+ Mapping_symbol_position msp(input_shndx, input_value & ~1U);
+ this->mapping_symbols_info_[msp] = sym_name[1];
+ }
+
+ if (st_type == elfcpp::STT_ARM_TFUNC
+ || (st_type == elfcpp::STT_FUNC && ((input_value & 1) != 0)))
+ {
+ // This is a THUMB function. Mark this and canonicalize the
+ // symbol value by setting LSB.
+ this->local_symbol_is_thumb_function_[i] = true;
+ if ((input_value & 1) == 0)
+ lv.set_input_value(input_value | 1);
+ }
+ }
+}
+
+// Relocate sections.
+template<bool big_endian>
+void
+Arm_relobj<big_endian>::do_relocate_sections(
+ const Symbol_table* symtab,
+ const Layout* layout,
+ const unsigned char* pshdrs,
+ typename Sized_relobj<32, big_endian>::Views* pviews)
+{
+ // Call parent to relocate sections.
+ Sized_relobj<32, big_endian>::do_relocate_sections(symtab, layout, pshdrs,
+ pviews);
+
+ // We do not generate stubs if doing a relocatable link.
+ if (parameters->options().relocatable())
+ return;
+
+ // Relocate stub tables.
+ unsigned int shnum = this->shnum();
+
+ Target_arm<big_endian>* arm_target =
+ Target_arm<big_endian>::default_target();
+
+ Relocate_info<32, big_endian> relinfo;
+ relinfo.symtab = symtab;
+ relinfo.layout = layout;
+ relinfo.object = this;
+
+ for (unsigned int i = 1; i < shnum; ++i)
+ {
+ Arm_input_section<big_endian>* arm_input_section =
+ arm_target->find_arm_input_section(this, i);
+
+ if (arm_input_section != NULL
+ && arm_input_section->is_stub_table_owner()
+ && !arm_input_section->stub_table()->empty())
+ {
+ // We cannot discard a section if it owns a stub table.
+ Output_section* os = this->output_section(i);
+ gold_assert(os != NULL);
+
+ relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
+ relinfo.reloc_shdr = NULL;
+ relinfo.data_shndx = i;
+ relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size;
+
+ gold_assert((*pviews)[i].view != NULL);
+
+ // We are passed the output section view. Adjust it to cover the
+ // stub table only.
+ Stub_table<big_endian>* stub_table = arm_input_section->stub_table();
+ gold_assert((stub_table->address() >= (*pviews)[i].address)
+ && ((stub_table->address() + stub_table->data_size())
+ <= (*pviews)[i].address + (*pviews)[i].view_size));
+
+ off_t offset = stub_table->address() - (*pviews)[i].address;
+ unsigned char* view = (*pviews)[i].view + offset;
+ Arm_address address = stub_table->address();
+ section_size_type view_size = stub_table->data_size();
+
+ stub_table->relocate_stubs(&relinfo, arm_target, os, view, address,
+ view_size);
+ }
+
+ // Apply Cortex A8 workaround if applicable.
+ if (this->section_has_cortex_a8_workaround(i))
+ {
+ unsigned char* view = (*pviews)[i].view;
+ Arm_address view_address = (*pviews)[i].address;
+ section_size_type view_size = (*pviews)[i].view_size;
+ Stub_table<big_endian>* stub_table = this->stub_tables_[i];
+
+ // Adjust view to cover section.
+ Output_section* os = this->output_section(i);
+ gold_assert(os != NULL);
+ Arm_address section_address =
+ this->simple_input_section_output_address(i, os);
+ uint64_t section_size = this->section_size(i);
+
+ gold_assert(section_address >= view_address
+ && ((section_address + section_size)
+ <= (view_address + view_size)));
+
+ unsigned char* section_view = view + (section_address - view_address);
+
+ // Apply the Cortex-A8 workaround to the output address range
+ // corresponding to this input section.
+ stub_table->apply_cortex_a8_workaround_to_address_range(
+ arm_target,
+ section_view,
+ section_address,
+ section_size);
+ }
+ }
+}
+
+// Find the linked text section of an EXIDX section by looking the the first
+// relocation. 4.4.1 of the EHABI specifications says that an EXIDX section
+// must be linked to to its associated code section via the sh_link field of
+// its section header. However, some tools are broken and the link is not
+// always set. LD just drops such an EXIDX section silently, causing the
+// associated code not unwindabled. Here we try a little bit harder to
+// discover the linked code section.
+//
+// PSHDR points to the section header of a relocation section of an EXIDX
+// section. If we can find a linked text section, return true and
+// store the text section index in the location PSHNDX. Otherwise
+// return false.
+
+template<bool big_endian>
+bool
+Arm_relobj<big_endian>::find_linked_text_section(
+ const unsigned char* pshdr,
+ const unsigned char* psyms,
+ unsigned int* pshndx)
+{
+ elfcpp::Shdr<32, big_endian> shdr(pshdr);
+
+ // If there is no relocation, we cannot find the linked text section.
+ size_t reloc_size;
+ if (shdr.get_sh_type() == elfcpp::SHT_REL)
+ reloc_size = elfcpp::Elf_sizes<32>::rel_size;
+ else
+ reloc_size = elfcpp::Elf_sizes<32>::rela_size;
+ size_t reloc_count = shdr.get_sh_size() / reloc_size;
+
+ // Get the relocations.
+ const unsigned char* prelocs =
+ this->get_view(shdr.get_sh_offset(), shdr.get_sh_size(), true, false);
+
+ // Find the REL31 relocation for the first word of the first EXIDX entry.
+ for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
+ {
+ Arm_address r_offset;
+ typename elfcpp::Elf_types<32>::Elf_WXword r_info;
+ if (shdr.get_sh_type() == elfcpp::SHT_REL)
+ {
+ typename elfcpp::Rel<32, big_endian> reloc(prelocs);
+ r_info = reloc.get_r_info();
+ r_offset = reloc.get_r_offset();
+ }
+ else
+ {
+ typename elfcpp::Rela<32, big_endian> reloc(prelocs);
+ r_info = reloc.get_r_info();
+ r_offset = reloc.get_r_offset();
+ }
+
+ unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
+ if (r_type != elfcpp::R_ARM_PREL31 && r_type != elfcpp::R_ARM_SBREL31)
+ continue;
+
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
+ if (r_sym == 0
+ || r_sym >= this->local_symbol_count()
+ || r_offset != 0)
+ continue;
+
+ // This is the relocation for the first word of the first EXIDX entry.
+ // We expect to see a local section symbol.
+ const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
+ elfcpp::Sym<32, big_endian> sym(psyms + r_sym * sym_size);
+ if (sym.get_st_type() == elfcpp::STT_SECTION)
+ {
+ bool is_ordinary;
+ *pshndx =
+ this->adjust_sym_shndx(r_sym, sym.get_st_shndx(), &is_ordinary);
+ gold_assert(is_ordinary);
+ return true;
+ }
+ else
+ return false;
+ }
+
+ return false;
+}
+
+// Make an EXIDX input section object for an EXIDX section whose index is
+// SHNDX. SHDR is the section header of the EXIDX section and TEXT_SHNDX
+// is the section index of the linked text section.
+
+template<bool big_endian>
+void
+Arm_relobj<big_endian>::make_exidx_input_section(
+ unsigned int shndx,
+ const elfcpp::Shdr<32, big_endian>& shdr,
+ unsigned int text_shndx,
+ const elfcpp::Shdr<32, big_endian>& text_shdr)
+{
+ // Create an Arm_exidx_input_section object for this EXIDX section.
+ Arm_exidx_input_section* exidx_input_section =
+ new Arm_exidx_input_section(this, shndx, text_shndx, shdr.get_sh_size(),
+ shdr.get_sh_addralign());
+
+ gold_assert(this->exidx_section_map_[shndx] == NULL);
+ this->exidx_section_map_[shndx] = exidx_input_section;
+
+ if (text_shndx == elfcpp::SHN_UNDEF || text_shndx >= this->shnum())
+ {
+ gold_error(_("EXIDX section %s(%u) links to invalid section %u in %s"),
+ this->section_name(shndx).c_str(), shndx, text_shndx,
+ this->name().c_str());
+ exidx_input_section->set_has_errors();
+ }
+ else if (this->exidx_section_map_[text_shndx] != NULL)
+ {
+ unsigned other_exidx_shndx =
+ this->exidx_section_map_[text_shndx]->shndx();
+ gold_error(_("EXIDX sections %s(%u) and %s(%u) both link to text section"
+ "%s(%u) in %s"),
+ this->section_name(shndx).c_str(), shndx,
+ this->section_name(other_exidx_shndx).c_str(),
+ other_exidx_shndx, this->section_name(text_shndx).c_str(),
+ text_shndx, this->name().c_str());
+ exidx_input_section->set_has_errors();
+ }
+ else
+ this->exidx_section_map_[text_shndx] = exidx_input_section;
+
+ // Check section flags of text section.
+ if ((text_shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
+ {
+ gold_error(_("EXIDX section %s(%u) links to non-allocated section %s(%u) "
+ " in %s"),
+ this->section_name(shndx).c_str(), shndx,
+ this->section_name(text_shndx).c_str(), text_shndx,
+ this->name().c_str());
+ exidx_input_section->set_has_errors();
+ }
+ else if ((text_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) == 0)
+ // I would like to make this an error but currenlty ld just ignores
+ // this.
+ gold_warning(_("EXIDX section %s(%u) links to non-executable section "
+ "%s(%u) in %s"),
+ this->section_name(shndx).c_str(), shndx,
+ this->section_name(text_shndx).c_str(), text_shndx,
+ this->name().c_str());
+}
+
+// Read the symbol information.
+
+template<bool big_endian>
+void
+Arm_relobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
+{
+ // Call parent class to read symbol information.
+ Sized_relobj<32, big_endian>::do_read_symbols(sd);
+
+ // If this input file is a binary file, it has no processor
+ // specific flags and attributes section.
+ Input_file::Format format = this->input_file()->format();
+ if (format != Input_file::FORMAT_ELF)
+ {
+ gold_assert(format == Input_file::FORMAT_BINARY);
+ this->merge_flags_and_attributes_ = false;
+ return;
+ }
+
+ // Read processor-specific flags in ELF file header.
+ const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
+ elfcpp::Elf_sizes<32>::ehdr_size,
+ true, false);
+ elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
+ this->processor_specific_flags_ = ehdr.get_e_flags();
+
+ // Go over the section headers and look for .ARM.attributes and .ARM.exidx
+ // sections.
+ std::vector<unsigned int> deferred_exidx_sections;
+ const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
+ const unsigned char* pshdrs = sd->section_headers->data();
+ const unsigned char *ps = pshdrs + shdr_size;
+ bool must_merge_flags_and_attributes = false;
+ for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
+ {
+ elfcpp::Shdr<32, big_endian> shdr(ps);
+
+ // Sometimes an object has no contents except the section name string
+ // table and an empty symbol table with the undefined symbol. We
+ // don't want to merge processor-specific flags from such an object.
+ if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB)
+ {
+ // Symbol table is not empty.
+ const elfcpp::Elf_types<32>::Elf_WXword sym_size =
+ elfcpp::Elf_sizes<32>::sym_size;
+ if (shdr.get_sh_size() > sym_size)
+ must_merge_flags_and_attributes = true;
+ }
+ else if (shdr.get_sh_type() != elfcpp::SHT_STRTAB)
+ // If this is neither an empty symbol table nor a string table,
+ // be conservative.
+ must_merge_flags_and_attributes = true;
+
+ if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
+ {
+ gold_assert(this->attributes_section_data_ == NULL);
+ section_offset_type section_offset = shdr.get_sh_offset();
+ section_size_type section_size =
+ convert_to_section_size_type(shdr.get_sh_size());
+ File_view* view = this->get_lasting_view(section_offset,
+ section_size, true, false);
+ this->attributes_section_data_ =
+ new Attributes_section_data(view->data(), section_size);
+ }
+ else if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
+ {
+ unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
+ if (text_shndx == elfcpp::SHN_UNDEF)
+ deferred_exidx_sections.push_back(i);
+ else
+ {
+ elfcpp::Shdr<32, big_endian> text_shdr(pshdrs
+ + text_shndx * shdr_size);
+ this->make_exidx_input_section(i, shdr, text_shndx, text_shdr);
+ }
+ }
+ }
+
+ // This is rare.
+ if (!must_merge_flags_and_attributes)
+ {
+ gold_assert(deferred_exidx_sections.empty());
+ this->merge_flags_and_attributes_ = false;
+ return;
+ }
+
+ // Some tools are broken and they do not set the link of EXIDX sections.
+ // We look at the first relocation to figure out the linked sections.
+ if (!deferred_exidx_sections.empty())
+ {
+ // We need to go over the section headers again to find the mapping
+ // from sections being relocated to their relocation sections. This is
+ // a bit inefficient as we could do that in the loop above. However,
+ // we do not expect any deferred EXIDX sections normally. So we do not
+ // want to slow down the most common path.
+ typedef Unordered_map<unsigned int, unsigned int> Reloc_map;
+ Reloc_map reloc_map;
+ ps = pshdrs + shdr_size;
+ for (unsigned int i = 1; i < this->shnum(); ++i, ps += shdr_size)
+ {
+ elfcpp::Shdr<32, big_endian> shdr(ps);
+ elfcpp::Elf_Word sh_type = shdr.get_sh_type();
+ if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA)
+ {
+ unsigned int info_shndx = this->adjust_shndx(shdr.get_sh_info());
+ if (info_shndx >= this->shnum())
+ gold_error(_("relocation section %u has invalid info %u"),
+ i, info_shndx);
+ Reloc_map::value_type value(info_shndx, i);
+ std::pair<Reloc_map::iterator, bool> result =
+ reloc_map.insert(value);
+ if (!result.second)
+ gold_error(_("section %u has multiple relocation sections "
+ "%u and %u"),
+ info_shndx, i, reloc_map[info_shndx]);
+ }
+ }
+
+ // Read the symbol table section header.
+ const unsigned int symtab_shndx = this->symtab_shndx();
+ elfcpp::Shdr<32, big_endian>
+ symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
+ gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
+
+ // Read the local symbols.
+ const int sym_size =elfcpp::Elf_sizes<32>::sym_size;
+ const unsigned int loccount = this->local_symbol_count();
+ gold_assert(loccount == symtabshdr.get_sh_info());
+ off_t locsize = loccount * sym_size;
+ const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
+ locsize, true, true);
+
+ // Process the deferred EXIDX sections.
+ for(unsigned int i = 0; i < deferred_exidx_sections.size(); ++i)
+ {
+ unsigned int shndx = deferred_exidx_sections[i];
+ elfcpp::Shdr<32, big_endian> shdr(pshdrs + shndx * shdr_size);
+ unsigned int text_shndx = elfcpp::SHN_UNDEF;
+ Reloc_map::const_iterator it = reloc_map.find(shndx);
+ if (it != reloc_map.end())
+ find_linked_text_section(pshdrs + it->second * shdr_size,
+ psyms, &text_shndx);
+ elfcpp::Shdr<32, big_endian> text_shdr(pshdrs
+ + text_shndx * shdr_size);
+ this->make_exidx_input_section(shndx, shdr, text_shndx, text_shdr);
+ }
+ }
+}
+
+// Process relocations for garbage collection. The ARM target uses .ARM.exidx
+// sections for unwinding. These sections are referenced implicitly by
+// text sections linked in the section headers. If we ignore these implict
+// references, the .ARM.exidx sections and any .ARM.extab sections they use
+// will be garbage-collected incorrectly. Hence we override the same function
+// in the base class to handle these implicit references.
+
+template<bool big_endian>
+void
+Arm_relobj<big_endian>::do_gc_process_relocs(Symbol_table* symtab,
+ Layout* layout,
+ Read_relocs_data* rd)
+{
+ // First, call base class method to process relocations in this object.
+ Sized_relobj<32, big_endian>::do_gc_process_relocs(symtab, layout, rd);
+
+ // If --gc-sections is not specified, there is nothing more to do.
+ // This happens when --icf is used but --gc-sections is not.
+ if (!parameters->options().gc_sections())
+ return;
+
+ unsigned int shnum = this->shnum();
+ const unsigned int shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
+ const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
+ shnum * shdr_size,
+ true, true);
+
+ // Scan section headers for sections of type SHT_ARM_EXIDX. Add references
+ // to these from the linked text sections.
+ const unsigned char* ps = pshdrs + shdr_size;
+ for (unsigned int i = 1; i < shnum; ++i, ps += shdr_size)
+ {
+ elfcpp::Shdr<32, big_endian> shdr(ps);
+ if (shdr.get_sh_type() == elfcpp::SHT_ARM_EXIDX)
+ {
+ // Found an .ARM.exidx section, add it to the set of reachable
+ // sections from its linked text section.
+ unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_link());
+ symtab->gc()->add_reference(this, text_shndx, this, i);
+ }
+ }
+}
+
+// Update output local symbol count. Owing to EXIDX entry merging, some local
+// symbols will be removed in output. Adjust output local symbol count
+// accordingly. We can only changed the static output local symbol count. It
+// is too late to change the dynamic symbols.
+
+template<bool big_endian>
+void
+Arm_relobj<big_endian>::update_output_local_symbol_count()
+{
+ // Caller should check that this needs updating. We want caller checking
+ // because output_local_symbol_count_needs_update() is most likely inlined.
+ gold_assert(this->output_local_symbol_count_needs_update_);
+
+ gold_assert(this->symtab_shndx() != -1U);
+ if (this->symtab_shndx() == 0)
+ {
+ // This object has no symbols. Weird but legal.
+ return;
+ }
+
+ // Read the symbol table section header.
+ const unsigned int symtab_shndx = this->symtab_shndx();
+ elfcpp::Shdr<32, big_endian>
+ symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
+ gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
+
+ // Read the local symbols.
+ const int sym_size = elfcpp::Elf_sizes<32>::sym_size;
+ const unsigned int loccount = this->local_symbol_count();
+ gold_assert(loccount == symtabshdr.get_sh_info());
+ off_t locsize = loccount * sym_size;
+ const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
+ locsize, true, true);
+
+ // Loop over the local symbols.
+
+ typedef typename Sized_relobj<32, big_endian>::Output_sections
+ Output_sections;
+ const Output_sections& out_sections(this->output_sections());
+ unsigned int shnum = this->shnum();
+ unsigned int count = 0;
+ // Skip the first, dummy, symbol.
+ psyms += sym_size;
+ for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
+ {
+ elfcpp::Sym<32, big_endian> sym(psyms);
+
+ Symbol_value<32>& lv((*this->local_values())[i]);
+
+ // This local symbol was already discarded by do_count_local_symbols.
+ if (lv.is_output_symtab_index_set() && !lv.has_output_symtab_entry())
+ continue;
+
+ bool is_ordinary;
+ unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
+ &is_ordinary);
+
+ if (shndx < shnum)
+ {
+ Output_section* os = out_sections[shndx];
+
+ // This local symbol no longer has an output section. Discard it.
+ if (os == NULL)
+ {
+ lv.set_no_output_symtab_entry();
+ continue;
+ }
+
+ // Currently we only discard parts of EXIDX input sections.
+ // We explicitly check for a merged EXIDX input section to avoid
+ // calling Output_section_data::output_offset unless necessary.
+ if ((this->get_output_section_offset(shndx) == invalid_address)
+ && (this->exidx_input_section_by_shndx(shndx) != NULL))
+ {
+ section_offset_type output_offset =
+ os->output_offset(this, shndx, lv.input_value());
+ if (output_offset == -1)
+ {
+ // This symbol is defined in a part of an EXIDX input section
+ // that is discarded due to entry merging.
+ lv.set_no_output_symtab_entry();
+ continue;
+ }
+ }
+ }
+
+ ++count;
+ }
+
+ this->set_output_local_symbol_count(count);
+ this->output_local_symbol_count_needs_update_ = false;
+}
+
+// Arm_dynobj methods.
+
+// Read the symbol information.
+
+template<bool big_endian>
+void
+Arm_dynobj<big_endian>::do_read_symbols(Read_symbols_data* sd)
+{
+ // Call parent class to read symbol information.
+ Sized_dynobj<32, big_endian>::do_read_symbols(sd);
+
+ // Read processor-specific flags in ELF file header.
+ const unsigned char* pehdr = this->get_view(elfcpp::file_header_offset,
+ elfcpp::Elf_sizes<32>::ehdr_size,
+ true, false);
+ elfcpp::Ehdr<32, big_endian> ehdr(pehdr);
+ this->processor_specific_flags_ = ehdr.get_e_flags();
+
+ // Read the attributes section if there is one.
+ // We read from the end because gas seems to put it near the end of
+ // the section headers.
+ const size_t shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
+ const unsigned char *ps =
+ sd->section_headers->data() + shdr_size * (this->shnum() - 1);
+ for (unsigned int i = this->shnum(); i > 0; --i, ps -= shdr_size)
+ {
+ elfcpp::Shdr<32, big_endian> shdr(ps);
+ if (shdr.get_sh_type() == elfcpp::SHT_ARM_ATTRIBUTES)
+ {
+ section_offset_type section_offset = shdr.get_sh_offset();
+ section_size_type section_size =
+ convert_to_section_size_type(shdr.get_sh_size());
+ File_view* view = this->get_lasting_view(section_offset,
+ section_size, true, false);
+ this->attributes_section_data_ =
+ new Attributes_section_data(view->data(), section_size);
+ break;
+ }
+ }
+}
+
+// Stub_addend_reader methods.
+
+// Read the addend of a REL relocation of type R_TYPE at VIEW.
+
+template<bool big_endian>
+elfcpp::Elf_types<32>::Elf_Swxword
+Stub_addend_reader<elfcpp::SHT_REL, big_endian>::operator()(
+ unsigned int r_type,
+ const unsigned char* view,
+ const typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc&) const
+{
+ typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
+
+ switch (r_type)
+ {
+ case elfcpp::R_ARM_CALL:
+ case elfcpp::R_ARM_JUMP24:
+ case elfcpp::R_ARM_PLT32:
+ {
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ const Valtype* wv = reinterpret_cast<const Valtype*>(view);
+ Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
+ return utils::sign_extend<26>(val << 2);
+ }
+
+ case elfcpp::R_ARM_THM_CALL:
+ case elfcpp::R_ARM_THM_JUMP24:
+ case elfcpp::R_ARM_THM_XPC22:
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ const Valtype* wv = reinterpret_cast<const Valtype*>(view);
+ Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
+ Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
+ return RelocFuncs::thumb32_branch_offset(upper_insn, lower_insn);
+ }
+
+ case elfcpp::R_ARM_THM_JUMP19:
+ {
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ const Valtype* wv = reinterpret_cast<const Valtype*>(view);
+ Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
+ Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
+ return RelocFuncs::thumb32_cond_branch_offset(upper_insn, lower_insn);
+ }
+
+ default:
+ gold_unreachable();
+ }
+}
+
+// Arm_output_data_got methods.
+
+// Add a GOT pair for R_ARM_TLS_GD32. The creates a pair of GOT entries.
+// The first one is initialized to be 1, which is the module index for
+// the main executable and the second one 0. A reloc of the type
+// R_ARM_TLS_DTPOFF32 will be created for the second GOT entry and will
+// be applied by gold. GSYM is a global symbol.
+//
+template<bool big_endian>
+void
+Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
+ unsigned int got_type,
+ Symbol* gsym)
+{
+ if (gsym->has_got_offset(got_type))
+ return;
+
+ // We are doing a static link. Just mark it as belong to module 1,
+ // the executable.
+ unsigned int got_offset = this->add_constant(1);
+ gsym->set_got_offset(got_type, got_offset);
+ got_offset = this->add_constant(0);
+ this->static_relocs_.push_back(Static_reloc(got_offset,
+ elfcpp::R_ARM_TLS_DTPOFF32,
+ gsym));
+}
+
+// Same as the above but for a local symbol.
+
+template<bool big_endian>
+void
+Arm_output_data_got<big_endian>::add_tls_gd32_with_static_reloc(
+ unsigned int got_type,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int index)
+{
+ if (object->local_has_got_offset(index, got_type))
+ return;
+
+ // We are doing a static link. Just mark it as belong to module 1,
+ // the executable.
+ unsigned int got_offset = this->add_constant(1);
+ object->set_local_got_offset(index, got_type, got_offset);
+ got_offset = this->add_constant(0);
+ this->static_relocs_.push_back(Static_reloc(got_offset,
+ elfcpp::R_ARM_TLS_DTPOFF32,
+ object, index));
+}
+
+template<bool big_endian>
+void
+Arm_output_data_got<big_endian>::do_write(Output_file* of)
+{
+ // Call parent to write out GOT.
+ Output_data_got<32, big_endian>::do_write(of);
+
+ // We are done if there is no fix up.
+ if (this->static_relocs_.empty())
+ return;
+
+ gold_assert(parameters->doing_static_link());
+
+ const off_t offset = this->offset();
+ const section_size_type oview_size =
+ convert_to_section_size_type(this->data_size());
+ unsigned char* const oview = of->get_output_view(offset, oview_size);
+
+ Output_segment* tls_segment = this->layout_->tls_segment();
+ gold_assert(tls_segment != NULL);
+
+ // The thread pointer $tp points to the TCB, which is followed by the
+ // TLS. So we need to adjust $tp relative addressing by this amount.
+ Arm_address aligned_tcb_size =
+ align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
+
+ for (size_t i = 0; i < this->static_relocs_.size(); ++i)
+ {
+ Static_reloc& reloc(this->static_relocs_[i]);
+
+ Arm_address value;
+ if (!reloc.symbol_is_global())
+ {
+ Sized_relobj<32, big_endian>* object = reloc.relobj();
+ const Symbol_value<32>* psymval =
+ reloc.relobj()->local_symbol(reloc.index());
+
+ // We are doing static linking. Issue an error and skip this
+ // relocation if the symbol is undefined or in a discarded_section.
+ bool is_ordinary;
+ unsigned int shndx = psymval->input_shndx(&is_ordinary);
+ if ((shndx == elfcpp::SHN_UNDEF)
+ || (is_ordinary
+ && shndx != elfcpp::SHN_UNDEF
+ && !object->is_section_included(shndx)
+ && !this->symbol_table_->is_section_folded(object, shndx)))
+ {
+ gold_error(_("undefined or discarded local symbol %u from "
+ " object %s in GOT"),
+ reloc.index(), reloc.relobj()->name().c_str());
+ continue;
+ }
+
+ value = psymval->value(object, 0);
+ }
+ else
+ {
+ const Symbol* gsym = reloc.symbol();
+ gold_assert(gsym != NULL);
+ if (gsym->is_forwarder())
+ gsym = this->symbol_table_->resolve_forwards(gsym);
+
+ // We are doing static linking. Issue an error and skip this
+ // relocation if the symbol is undefined or in a discarded_section
+ // unless it is a weakly_undefined symbol.
+ if ((gsym->is_defined_in_discarded_section()
+ || gsym->is_undefined())
+ && !gsym->is_weak_undefined())
+ {
+ gold_error(_("undefined or discarded symbol %s in GOT"),
+ gsym->name());
+ continue;
+ }
+
+ if (!gsym->is_weak_undefined())
+ {
+ const Sized_symbol<32>* sym =
+ static_cast<const Sized_symbol<32>*>(gsym);
+ value = sym->value();
+ }
+ else
+ value = 0;
+ }
+
+ unsigned got_offset = reloc.got_offset();
+ gold_assert(got_offset < oview_size);
+
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
+ Valtype x;
+ switch (reloc.r_type())
+ {
+ case elfcpp::R_ARM_TLS_DTPOFF32:
+ x = value;
+ break;
+ case elfcpp::R_ARM_TLS_TPOFF32:
+ x = value + aligned_tcb_size;
+ break;
+ default:
+ gold_unreachable();
+ }
+ elfcpp::Swap<32, big_endian>::writeval(wv, x);
+ }
+
+ of->write_output_view(offset, oview_size, oview);
+}
+
+// A class to handle the PLT data.
+
+template<bool big_endian>
+class Output_data_plt_arm : public Output_section_data
+{
+ public:
+ typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
+ Reloc_section;
+
+ Output_data_plt_arm(Layout*, Output_data_space*);
+
+ // Add an entry to the PLT.
+ void
+ add_entry(Symbol* gsym);
+
+ // Return the .rel.plt section data.
+ const Reloc_section*
+ rel_plt() const
+ { return this->rel_; }
+
+ protected:
+ void
+ do_adjust_output_section(Output_section* os);
+
+ // Write to a map file.
+ void
+ do_print_to_mapfile(Mapfile* mapfile) const
+ { mapfile->print_output_data(this, _("** PLT")); }
+
+ private:
+ // Template for the first PLT entry.
+ static const uint32_t first_plt_entry[5];
+
+ // Template for subsequent PLT entries.
+ static const uint32_t plt_entry[3];
+
+ // Set the final size.
+ void
+ set_final_data_size()
+ {
+ this->set_data_size(sizeof(first_plt_entry)
+ + this->count_ * sizeof(plt_entry));
+ }
+
+ // Write out the PLT data.
+ void
+ do_write(Output_file*);
+
+ // The reloc section.
+ Reloc_section* rel_;
+ // The .got.plt section.
+ Output_data_space* got_plt_;
+ // The number of PLT entries.
+ unsigned int count_;
+};
+
+// Create the PLT section. The ordinary .got section is an argument,
+// since we need to refer to the start. We also create our own .got
+// section just for PLT entries.
+
+template<bool big_endian>
+Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
+ Output_data_space* got_plt)
+ : Output_section_data(4), got_plt_(got_plt), count_(0)
+{
+ this->rel_ = new Reloc_section(false);
+ layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
+ elfcpp::SHF_ALLOC, this->rel_, true, false,
+ false, false);
+}
+
+template<bool big_endian>
+void
+Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
+{
+ os->set_entsize(0);
+}
+
+// Add an entry to the PLT.
+
+template<bool big_endian>
+void
+Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
+{
+ gold_assert(!gsym->has_plt_offset());
+
+ // Note that when setting the PLT offset we skip the initial
+ // reserved PLT entry.
+ gsym->set_plt_offset((this->count_) * sizeof(plt_entry)
+ + sizeof(first_plt_entry));
+
+ ++this->count_;
+
+ section_offset_type got_offset = this->got_plt_->current_data_size();
+
+ // Every PLT entry needs a GOT entry which points back to the PLT
+ // entry (this will be changed by the dynamic linker, normally
+ // lazily when the function is called).
+ this->got_plt_->set_current_data_size(got_offset + 4);
+
+ // Every PLT entry needs a reloc.
+ gsym->set_needs_dynsym_entry();
+ this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
+ got_offset);
+
+ // Note that we don't need to save the symbol. The contents of the
+ // PLT are independent of which symbols are used. The symbols only
+ // appear in the relocations.
+}
+
+// ARM PLTs.
+// FIXME: This is not very flexible. Right now this has only been tested
+// on armv5te. If we are to support additional architecture features like
+// Thumb-2 or BE8, we need to make this more flexible like GNU ld.
+
+// The first entry in the PLT.
+template<bool big_endian>
+const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] =
+{
+ 0xe52de004, // str lr, [sp, #-4]!
+ 0xe59fe004, // ldr lr, [pc, #4]
+ 0xe08fe00e, // add lr, pc, lr
+ 0xe5bef008, // ldr pc, [lr, #8]!
+ 0x00000000, // &GOT[0] - .
+};
+
+// Subsequent entries in the PLT.
+
+template<bool big_endian>
+const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] =
+{
+ 0xe28fc600, // add ip, pc, #0xNN00000
+ 0xe28cca00, // add ip, ip, #0xNN000
+ 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
+};
+
+// Write out the PLT. This uses the hand-coded instructions above,
+// and adjusts them as needed. This is all specified by the arm ELF
+// Processor Supplement.
+
+template<bool big_endian>
+void
+Output_data_plt_arm<big_endian>::do_write(Output_file* of)
+{
+ const off_t offset = this->offset();
+ const section_size_type oview_size =
+ convert_to_section_size_type(this->data_size());
+ unsigned char* const oview = of->get_output_view(offset, oview_size);
+
+ const off_t got_file_offset = this->got_plt_->offset();
+ const section_size_type got_size =
+ convert_to_section_size_type(this->got_plt_->data_size());
+ unsigned char* const got_view = of->get_output_view(got_file_offset,
+ got_size);
+ unsigned char* pov = oview;
+
+ Arm_address plt_address = this->address();
+ Arm_address got_address = this->got_plt_->address();
+
+ // Write first PLT entry. All but the last word are constants.
+ const size_t num_first_plt_words = (sizeof(first_plt_entry)
+ / sizeof(plt_entry[0]));
+ for (size_t i = 0; i < num_first_plt_words - 1; i++)
+ elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
+ // Last word in first PLT entry is &GOT[0] - .
+ elfcpp::Swap<32, big_endian>::writeval(pov + 16,
+ got_address - (plt_address + 16));
+ pov += sizeof(first_plt_entry);
+
+ unsigned char* got_pov = got_view;
+
+ memset(got_pov, 0, 12);
+ got_pov += 12;
+
+ const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
+ unsigned int plt_offset = sizeof(first_plt_entry);
+ unsigned int plt_rel_offset = 0;
+ unsigned int got_offset = 12;
+ const unsigned int count = this->count_;
+ for (unsigned int i = 0;
+ i < count;
+ ++i,
+ pov += sizeof(plt_entry),
+ got_pov += 4,
+ plt_offset += sizeof(plt_entry),
+ plt_rel_offset += rel_size,
+ got_offset += 4)
+ {
+ // Set and adjust the PLT entry itself.
+ int32_t offset = ((got_address + got_offset)
+ - (plt_address + plt_offset + 8));
+
+ gold_assert(offset >= 0 && offset < 0x0fffffff);
+ uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
+ elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
+ uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
+ uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
+
+ // Set the entry in the GOT.
+ elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
+ }
+
+ gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
+ gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
+
+ of->write_output_view(offset, oview_size, oview);
+ of->write_output_view(got_file_offset, got_size, got_view);
+}
+
+// Create a PLT entry for a global symbol.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
+ Symbol* gsym)
+{
+ if (gsym->has_plt_offset())
+ return;
+
+ if (this->plt_ == NULL)
+ {
+ // Create the GOT sections first.
+ this->got_section(symtab, layout);
+
+ this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_);
+ layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
+ (elfcpp::SHF_ALLOC
+ | elfcpp::SHF_EXECINSTR),
+ this->plt_, false, false, false, false);
+ }
+ this->plt_->add_entry(gsym);
+}
+
+// Get the section to use for TLS_DESC relocations.
+
+template<bool big_endian>
+typename Target_arm<big_endian>::Reloc_section*
+Target_arm<big_endian>::rel_tls_desc_section(Layout* layout) const
+{
+ return this->plt_section()->rel_tls_desc(layout);
+}
+
+// Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::define_tls_base_symbol(
+ Symbol_table* symtab,
+ Layout* layout)
+{
+ if (this->tls_base_symbol_defined_)
+ return;
+
+ Output_segment* tls_segment = layout->tls_segment();
+ if (tls_segment != NULL)
+ {
+ bool is_exec = parameters->options().output_is_executable();
+ symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
+ Symbol_table::PREDEFINED,
+ tls_segment, 0, 0,
+ elfcpp::STT_TLS,
+ elfcpp::STB_LOCAL,
+ elfcpp::STV_HIDDEN, 0,
+ (is_exec
+ ? Symbol::SEGMENT_END
+ : Symbol::SEGMENT_START),
+ true);
+ }
+ this->tls_base_symbol_defined_ = true;
+}
+
+// Create a GOT entry for the TLS module index.
+
+template<bool big_endian>
+unsigned int
+Target_arm<big_endian>::got_mod_index_entry(
+ Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<32, big_endian>* object)
+{
+ if (this->got_mod_index_offset_ == -1U)
+ {
+ gold_assert(symtab != NULL && layout != NULL && object != NULL);
+ Arm_output_data_got<big_endian>* got = this->got_section(symtab, layout);
+ unsigned int got_offset;
+ if (!parameters->doing_static_link())
+ {
+ got_offset = got->add_constant(0);
+ Reloc_section* rel_dyn = this->rel_dyn_section(layout);
+ rel_dyn->add_local(object, 0, elfcpp::R_ARM_TLS_DTPMOD32, got,
+ got_offset);
+ }
+ else
+ {
+ // We are doing a static link. Just mark it as belong to module 1,
+ // the executable.
+ got_offset = got->add_constant(1);
+ }
+
+ got->add_constant(0);
+ this->got_mod_index_offset_ = got_offset;
+ }
+ return this->got_mod_index_offset_;
+}
+
+// Optimize the TLS relocation type based on what we know about the
+// symbol. IS_FINAL is true if the final address of this symbol is
+// known at link time.
+
+template<bool big_endian>
+tls::Tls_optimization
+Target_arm<big_endian>::optimize_tls_reloc(bool, int)
+{
+ // FIXME: Currently we do not do any TLS optimization.
+ return tls::TLSOPT_NONE;
+}
+
+// Report an unsupported relocation against a local symbol.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::Scan::unsupported_reloc_local(
+ Sized_relobj<32, big_endian>* object,
+ unsigned int r_type)
+{
+ gold_error(_("%s: unsupported reloc %u against local symbol"),
+ object->name().c_str(), r_type);
+}
+
+// We are about to emit a dynamic relocation of type R_TYPE. If the
+// dynamic linker does not support it, issue an error. The GNU linker
+// only issues a non-PIC error for an allocated read-only section.
+// Here we know the section is allocated, but we don't know that it is
+// read-only. But we check for all the relocation types which the
+// glibc dynamic linker supports, so it seems appropriate to issue an
+// error even if the section is not read-only.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
+ unsigned int r_type)
+{
+ switch (r_type)
+ {
+ // These are the relocation types supported by glibc for ARM.
+ case elfcpp::R_ARM_RELATIVE:
+ case elfcpp::R_ARM_COPY:
+ case elfcpp::R_ARM_GLOB_DAT:
+ case elfcpp::R_ARM_JUMP_SLOT:
+ case elfcpp::R_ARM_ABS32:
+ case elfcpp::R_ARM_ABS32_NOI:
+ case elfcpp::R_ARM_PC24:
+ // FIXME: The following 3 types are not supported by Android's dynamic
+ // linker.
+ case elfcpp::R_ARM_TLS_DTPMOD32:
+ case elfcpp::R_ARM_TLS_DTPOFF32:
+ case elfcpp::R_ARM_TLS_TPOFF32:
+ return;
+
+ default:
+ {
+ // This prevents us from issuing more than one error per reloc
+ // section. But we can still wind up issuing more than one
+ // error per object file.
+ if (this->issued_non_pic_error_)
+ return;
+ const Arm_reloc_property* reloc_property =
+ arm_reloc_property_table->get_reloc_property(r_type);
+ gold_assert(reloc_property != NULL);
+ object->error(_("requires unsupported dynamic reloc %s; "
+ "recompile with -fPIC"),
+ reloc_property->name().c_str());
+ this->issued_non_pic_error_ = true;
+ return;
+ }
+
+ case elfcpp::R_ARM_NONE:
+ gold_unreachable();
+ }
+}
+
+// Scan a relocation for a local symbol.
+// FIXME: This only handles a subset of relocation types used by Android
+// on ARM v5te devices.
+
+template<bool big_endian>
+inline void
+Target_arm<big_endian>::Scan::local(Symbol_table* symtab,
+ Layout* layout,
+ Target_arm* target,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ Output_section* output_section,
+ const elfcpp::Rel<32, big_endian>& reloc,
+ unsigned int r_type,
+ const elfcpp::Sym<32, big_endian>& lsym)
+{
+ r_type = get_real_reloc_type(r_type);
+ switch (r_type)
+ {
+ case elfcpp::R_ARM_NONE:
+ case elfcpp::R_ARM_V4BX:
+ case elfcpp::R_ARM_GNU_VTENTRY:
+ case elfcpp::R_ARM_GNU_VTINHERIT:
+ break;
+
+ case elfcpp::R_ARM_ABS32:
+ case elfcpp::R_ARM_ABS32_NOI:
+ // If building a shared library (or a position-independent
+ // executable), we need to create a dynamic relocation for
+ // this location. The relocation applied at link time will
+ // apply the link-time value, so we flag the location with
+ // an R_ARM_RELATIVE relocation so the dynamic loader can
+ // relocate it easily.
+ if (parameters->options().output_is_position_independent())
+ {
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
+ // If we are to add more other reloc types than R_ARM_ABS32,
+ // we need to add check_non_pic(object, r_type) here.
+ rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
+ output_section, data_shndx,
+ reloc.get_r_offset());
+ }
+ break;
+
+ case elfcpp::R_ARM_ABS16:
+ case elfcpp::R_ARM_ABS12:
+ case elfcpp::R_ARM_THM_ABS5:
+ case elfcpp::R_ARM_ABS8:
+ case elfcpp::R_ARM_BASE_ABS:
+ case elfcpp::R_ARM_MOVW_ABS_NC:
+ case elfcpp::R_ARM_MOVT_ABS:
+ case elfcpp::R_ARM_THM_MOVW_ABS_NC:
+ case elfcpp::R_ARM_THM_MOVT_ABS:
+ // If building a shared library (or a position-independent
+ // executable), we need to create a dynamic relocation for
+ // this location. Because the addend needs to remain in the
+ // data section, we need to be careful not to apply this
+ // relocation statically.
+ if (parameters->options().output_is_position_independent())
+ {
+ check_non_pic(object, r_type);
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
+ if (lsym.get_st_type() != elfcpp::STT_SECTION)
+ rel_dyn->add_local(object, r_sym, r_type, output_section,
+ data_shndx, reloc.get_r_offset());
+ else
+ {
+ gold_assert(lsym.get_st_value() == 0);
+ unsigned int shndx = lsym.get_st_shndx();
+ bool is_ordinary;
+ shndx = object->adjust_sym_shndx(r_sym, shndx,
+ &is_ordinary);
+ if (!is_ordinary)
+ object->error(_("section symbol %u has bad shndx %u"),
+ r_sym, shndx);
+ else
+ rel_dyn->add_local_section(object, shndx,
+ r_type, output_section,
+ data_shndx, reloc.get_r_offset());
+ }
+ }
+ break;
+
+ case elfcpp::R_ARM_PC24:
+ case elfcpp::R_ARM_REL32:
+ case elfcpp::R_ARM_LDR_PC_G0:
+ case elfcpp::R_ARM_SBREL32:
+ case elfcpp::R_ARM_THM_CALL:
+ case elfcpp::R_ARM_THM_PC8:
+ case elfcpp::R_ARM_BASE_PREL:
+ case elfcpp::R_ARM_PLT32:
+ case elfcpp::R_ARM_CALL:
+ case elfcpp::R_ARM_JUMP24:
+ case elfcpp::R_ARM_THM_JUMP24:
+ case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
+ case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
+ case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
+ case elfcpp::R_ARM_SBREL31:
+ case elfcpp::R_ARM_PREL31:
+ case elfcpp::R_ARM_MOVW_PREL_NC:
+ case elfcpp::R_ARM_MOVT_PREL:
+ case elfcpp::R_ARM_THM_MOVW_PREL_NC:
+ case elfcpp::R_ARM_THM_MOVT_PREL:
+ case elfcpp::R_ARM_THM_JUMP19:
+ case elfcpp::R_ARM_THM_JUMP6:
+ case elfcpp::R_ARM_THM_ALU_PREL_11_0:
+ case elfcpp::R_ARM_THM_PC12:
+ case elfcpp::R_ARM_REL32_NOI:
+ case elfcpp::R_ARM_ALU_PC_G0_NC:
+ case elfcpp::R_ARM_ALU_PC_G0:
+ case elfcpp::R_ARM_ALU_PC_G1_NC:
+ case elfcpp::R_ARM_ALU_PC_G1:
+ case elfcpp::R_ARM_ALU_PC_G2:
+ case elfcpp::R_ARM_LDR_PC_G1:
+ case elfcpp::R_ARM_LDR_PC_G2:
+ case elfcpp::R_ARM_LDRS_PC_G0:
+ case elfcpp::R_ARM_LDRS_PC_G1:
+ case elfcpp::R_ARM_LDRS_PC_G2:
+ case elfcpp::R_ARM_LDC_PC_G0:
+ case elfcpp::R_ARM_LDC_PC_G1:
+ case elfcpp::R_ARM_LDC_PC_G2:
+ case elfcpp::R_ARM_ALU_SB_G0_NC:
+ case elfcpp::R_ARM_ALU_SB_G0:
+ case elfcpp::R_ARM_ALU_SB_G1_NC:
+ case elfcpp::R_ARM_ALU_SB_G1:
+ case elfcpp::R_ARM_ALU_SB_G2:
+ case elfcpp::R_ARM_LDR_SB_G0:
+ case elfcpp::R_ARM_LDR_SB_G1:
+ case elfcpp::R_ARM_LDR_SB_G2:
+ case elfcpp::R_ARM_LDRS_SB_G0:
+ case elfcpp::R_ARM_LDRS_SB_G1:
+ case elfcpp::R_ARM_LDRS_SB_G2:
+ case elfcpp::R_ARM_LDC_SB_G0:
+ case elfcpp::R_ARM_LDC_SB_G1:
+ case elfcpp::R_ARM_LDC_SB_G2:
+ case elfcpp::R_ARM_MOVW_BREL_NC:
+ case elfcpp::R_ARM_MOVT_BREL:
+ case elfcpp::R_ARM_MOVW_BREL:
+ case elfcpp::R_ARM_THM_MOVW_BREL_NC:
+ case elfcpp::R_ARM_THM_MOVT_BREL:
+ case elfcpp::R_ARM_THM_MOVW_BREL:
+ case elfcpp::R_ARM_THM_JUMP11:
+ case elfcpp::R_ARM_THM_JUMP8:
+ // We don't need to do anything for a relative addressing relocation
+ // against a local symbol if it does not reference the GOT.
+ break;
+
+ case elfcpp::R_ARM_GOTOFF32:
+ case elfcpp::R_ARM_GOTOFF12:
+ // We need a GOT section:
+ target->got_section(symtab, layout);
+ break;
+
+ case elfcpp::R_ARM_GOT_BREL:
+ case elfcpp::R_ARM_GOT_PREL:
+ {
+ // The symbol requires a GOT entry.
+ Arm_output_data_got<big_endian>* got =
+ target->got_section(symtab, layout);
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
+ if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
+ {
+ // If we are generating a shared object, we need to add a
+ // dynamic RELATIVE relocation for this symbol's GOT entry.
+ if (parameters->options().output_is_position_independent())
+ {
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
+ rel_dyn->add_local_relative(
+ object, r_sym, elfcpp::R_ARM_RELATIVE, got,
+ object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
+ }
+ }
+ }
+ break;
+
+ case elfcpp::R_ARM_TARGET1:
+ case elfcpp::R_ARM_TARGET2:
+ // This should have been mapped to another type already.
+ // Fall through.
+ case elfcpp::R_ARM_COPY:
+ case elfcpp::R_ARM_GLOB_DAT:
+ case elfcpp::R_ARM_JUMP_SLOT:
+ case elfcpp::R_ARM_RELATIVE:
+ // These are relocations which should only be seen by the
+ // dynamic linker, and should never be seen here.
+ gold_error(_("%s: unexpected reloc %u in object file"),
+ object->name().c_str(), r_type);
+ break;
+
+
+ // These are initial TLS relocs, which are expected when
+ // linking.
+ case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
+ case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
+ case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
+ case elfcpp::R_ARM_TLS_IE32: // Initial-exec
+ case elfcpp::R_ARM_TLS_LE32: // Local-exec
+ {
+ bool output_is_shared = parameters->options().shared();
+ const tls::Tls_optimization optimized_type
+ = Target_arm<big_endian>::optimize_tls_reloc(!output_is_shared,
+ r_type);
+ switch (r_type)
+ {
+ case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
+ if (optimized_type == tls::TLSOPT_NONE)
+ {
+ // Create a pair of GOT entries for the module index and
+ // dtv-relative offset.
+ Arm_output_data_got<big_endian>* got
+ = target->got_section(symtab, layout);
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
+ unsigned int shndx = lsym.get_st_shndx();
+ bool is_ordinary;
+ shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
+ if (!is_ordinary)
+ {
+ object->error(_("local symbol %u has bad shndx %u"),
+ r_sym, shndx);
+ break;
+ }
+
+ if (!parameters->doing_static_link())
+ got->add_local_pair_with_rel(object, r_sym, shndx,
+ GOT_TYPE_TLS_PAIR,
+ target->rel_dyn_section(layout),
+ elfcpp::R_ARM_TLS_DTPMOD32, 0);
+ else
+ got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR,
+ object, r_sym);
+ }
+ else
+ // FIXME: TLS optimization not supported yet.
+ gold_unreachable();
+ break;
+
+ case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
+ if (optimized_type == tls::TLSOPT_NONE)
+ {
+ // Create a GOT entry for the module index.
+ target->got_mod_index_entry(symtab, layout, object);
+ }
+ else
+ // FIXME: TLS optimization not supported yet.
+ gold_unreachable();
+ break;
+
+ case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
+ break;
+
+ case elfcpp::R_ARM_TLS_IE32: // Initial-exec
+ layout->set_has_static_tls();
+ if (optimized_type == tls::TLSOPT_NONE)
+ {
+ // Create a GOT entry for the tp-relative offset.
+ Arm_output_data_got<big_endian>* got
+ = target->got_section(symtab, layout);
+ unsigned int r_sym =
+ elfcpp::elf_r_sym<32>(reloc.get_r_info());
+ if (!parameters->doing_static_link())
+ got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
+ target->rel_dyn_section(layout),
+ elfcpp::R_ARM_TLS_TPOFF32);
+ else if (!object->local_has_got_offset(r_sym,
+ GOT_TYPE_TLS_OFFSET))
+ {
+ got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
+ unsigned int got_offset =
+ object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
+ got->add_static_reloc(got_offset,
+ elfcpp::R_ARM_TLS_TPOFF32, object,
+ r_sym);
+ }
+ }
+ else
+ // FIXME: TLS optimization not supported yet.
+ gold_unreachable();
+ break;
+
+ case elfcpp::R_ARM_TLS_LE32: // Local-exec
+ layout->set_has_static_tls();
+ if (output_is_shared)
+ {
+ // We need to create a dynamic relocation.
+ gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ rel_dyn->add_local(object, r_sym, elfcpp::R_ARM_TLS_TPOFF32,
+ output_section, data_shndx,
+ reloc.get_r_offset());
+ }
+ break;
+
+ default:
+ gold_unreachable();
+ }
+ }
+ break;
+
+ default:
+ unsupported_reloc_local(object, r_type);
+ break;
+ }
+}
+
+// Report an unsupported relocation against a global symbol.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::Scan::unsupported_reloc_global(
+ Sized_relobj<32, big_endian>* object,
+ unsigned int r_type,
+ Symbol* gsym)
+{
+ gold_error(_("%s: unsupported reloc %u against global symbol %s"),
+ object->name().c_str(), r_type, gsym->demangled_name().c_str());
+}
+
+template<bool big_endian>
+inline bool
+Target_arm<big_endian>::Scan::possible_function_pointer_reloc(
+ unsigned int r_type)
+{
+ switch (r_type)
+ {
+ case elfcpp::R_ARM_PC24:
+ case elfcpp::R_ARM_THM_CALL:
+ case elfcpp::R_ARM_PLT32:
+ case elfcpp::R_ARM_CALL:
+ case elfcpp::R_ARM_JUMP24:
+ case elfcpp::R_ARM_THM_JUMP24:
+ case elfcpp::R_ARM_SBREL31:
+ case elfcpp::R_ARM_PREL31:
+ case elfcpp::R_ARM_THM_JUMP19:
+ case elfcpp::R_ARM_THM_JUMP6:
+ case elfcpp::R_ARM_THM_JUMP11:
+ case elfcpp::R_ARM_THM_JUMP8:
+ // All the relocations above are branches except SBREL31 and PREL31.
+ return false;
+
+ default:
+ // Be conservative and assume this is a function pointer.
+ return true;
+ }
+}
+
+template<bool big_endian>
+inline bool
+Target_arm<big_endian>::Scan::local_reloc_may_be_function_pointer(
+ Symbol_table*,
+ Layout*,
+ Target_arm<big_endian>* target,
+ Sized_relobj<32, big_endian>*,
+ unsigned int,
+ Output_section*,
+ const elfcpp::Rel<32, big_endian>&,
+ unsigned int r_type,
+ const elfcpp::Sym<32, big_endian>&)
+{
+ r_type = target->get_real_reloc_type(r_type);
+ return possible_function_pointer_reloc(r_type);
+}
+
+template<bool big_endian>
+inline bool
+Target_arm<big_endian>::Scan::global_reloc_may_be_function_pointer(
+ Symbol_table*,
+ Layout*,
+ Target_arm<big_endian>* target,
+ Sized_relobj<32, big_endian>*,
+ unsigned int,
+ Output_section*,
+ const elfcpp::Rel<32, big_endian>&,
+ unsigned int r_type,
+ Symbol* gsym)
+{
+ // GOT is not a function.
+ if (strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
+ return false;
+
+ r_type = target->get_real_reloc_type(r_type);
+ return possible_function_pointer_reloc(r_type);
+}
+
+// Scan a relocation for a global symbol.
+
+template<bool big_endian>
+inline void
+Target_arm<big_endian>::Scan::global(Symbol_table* symtab,
+ Layout* layout,
+ Target_arm* target,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ Output_section* output_section,
+ const elfcpp::Rel<32, big_endian>& reloc,
+ unsigned int r_type,
+ Symbol* gsym)
+{
+ // A reference to _GLOBAL_OFFSET_TABLE_ implies that we need a got
+ // section. We check here to avoid creating a dynamic reloc against
+ // _GLOBAL_OFFSET_TABLE_.
+ if (!target->has_got_section()
+ && strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
+ target->got_section(symtab, layout);
+
+ r_type = get_real_reloc_type(r_type);
+ switch (r_type)
+ {
+ case elfcpp::R_ARM_NONE:
+ case elfcpp::R_ARM_V4BX:
+ case elfcpp::R_ARM_GNU_VTENTRY:
+ case elfcpp::R_ARM_GNU_VTINHERIT:
+ break;
+
+ case elfcpp::R_ARM_ABS32:
+ case elfcpp::R_ARM_ABS16:
+ case elfcpp::R_ARM_ABS12:
+ case elfcpp::R_ARM_THM_ABS5:
+ case elfcpp::R_ARM_ABS8:
+ case elfcpp::R_ARM_BASE_ABS:
+ case elfcpp::R_ARM_MOVW_ABS_NC:
+ case elfcpp::R_ARM_MOVT_ABS:
+ case elfcpp::R_ARM_THM_MOVW_ABS_NC:
+ case elfcpp::R_ARM_THM_MOVT_ABS:
+ case elfcpp::R_ARM_ABS32_NOI:
+ // Absolute addressing relocations.
+ {
+ // Make a PLT entry if necessary.
+ if (this->symbol_needs_plt_entry(gsym))
+ {
+ target->make_plt_entry(symtab, layout, gsym);
+ // Since this is not a PC-relative relocation, we may be
+ // taking the address of a function. In that case we need to
+ // set the entry in the dynamic symbol table to the address of
+ // the PLT entry.
+ if (gsym->is_from_dynobj() && !parameters->options().shared())
+ gsym->set_needs_dynsym_value();
+ }
+ // Make a dynamic relocation if necessary.
+ if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
+ {
+ if (gsym->may_need_copy_reloc())
+ {
+ target->copy_reloc(symtab, layout, object,
+ data_shndx, output_section, gsym, reloc);
+ }
+ else if ((r_type == elfcpp::R_ARM_ABS32
+ || r_type == elfcpp::R_ARM_ABS32_NOI)
+ && gsym->can_use_relative_reloc(false))
+ {
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
+ output_section, object,
+ data_shndx, reloc.get_r_offset());
+ }
+ else
+ {
+ check_non_pic(object, r_type);
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ rel_dyn->add_global(gsym, r_type, output_section, object,
+ data_shndx, reloc.get_r_offset());
+ }
+ }
+ }
+ break;
+
+ case elfcpp::R_ARM_GOTOFF32:
+ case elfcpp::R_ARM_GOTOFF12:
+ // We need a GOT section.
+ target->got_section(symtab, layout);
+ break;
+
+ case elfcpp::R_ARM_REL32:
+ case elfcpp::R_ARM_LDR_PC_G0:
+ case elfcpp::R_ARM_SBREL32:
+ case elfcpp::R_ARM_THM_PC8:
+ case elfcpp::R_ARM_BASE_PREL:
+ case elfcpp::R_ARM_LDR_SBREL_11_0_NC:
+ case elfcpp::R_ARM_ALU_SBREL_19_12_NC:
+ case elfcpp::R_ARM_ALU_SBREL_27_20_CK:
+ case elfcpp::R_ARM_MOVW_PREL_NC:
+ case elfcpp::R_ARM_MOVT_PREL:
+ case elfcpp::R_ARM_THM_MOVW_PREL_NC:
+ case elfcpp::R_ARM_THM_MOVT_PREL:
+ case elfcpp::R_ARM_THM_ALU_PREL_11_0:
+ case elfcpp::R_ARM_THM_PC12:
+ case elfcpp::R_ARM_REL32_NOI:
+ case elfcpp::R_ARM_ALU_PC_G0_NC:
+ case elfcpp::R_ARM_ALU_PC_G0:
+ case elfcpp::R_ARM_ALU_PC_G1_NC:
+ case elfcpp::R_ARM_ALU_PC_G1:
+ case elfcpp::R_ARM_ALU_PC_G2:
+ case elfcpp::R_ARM_LDR_PC_G1:
+ case elfcpp::R_ARM_LDR_PC_G2:
+ case elfcpp::R_ARM_LDRS_PC_G0:
+ case elfcpp::R_ARM_LDRS_PC_G1:
+ case elfcpp::R_ARM_LDRS_PC_G2:
+ case elfcpp::R_ARM_LDC_PC_G0:
+ case elfcpp::R_ARM_LDC_PC_G1:
+ case elfcpp::R_ARM_LDC_PC_G2:
+ case elfcpp::R_ARM_ALU_SB_G0_NC:
+ case elfcpp::R_ARM_ALU_SB_G0:
+ case elfcpp::R_ARM_ALU_SB_G1_NC:
+ case elfcpp::R_ARM_ALU_SB_G1:
+ case elfcpp::R_ARM_ALU_SB_G2:
+ case elfcpp::R_ARM_LDR_SB_G0:
+ case elfcpp::R_ARM_LDR_SB_G1:
+ case elfcpp::R_ARM_LDR_SB_G2:
+ case elfcpp::R_ARM_LDRS_SB_G0:
+ case elfcpp::R_ARM_LDRS_SB_G1:
+ case elfcpp::R_ARM_LDRS_SB_G2:
+ case elfcpp::R_ARM_LDC_SB_G0:
+ case elfcpp::R_ARM_LDC_SB_G1:
+ case elfcpp::R_ARM_LDC_SB_G2:
+ case elfcpp::R_ARM_MOVW_BREL_NC:
+ case elfcpp::R_ARM_MOVT_BREL:
+ case elfcpp::R_ARM_MOVW_BREL:
+ case elfcpp::R_ARM_THM_MOVW_BREL_NC:
+ case elfcpp::R_ARM_THM_MOVT_BREL:
+ case elfcpp::R_ARM_THM_MOVW_BREL:
+ // Relative addressing relocations.
+ {
+ // Make a dynamic relocation if necessary.
+ int flags = Symbol::NON_PIC_REF;
+ if (gsym->needs_dynamic_reloc(flags))
+ {
+ if (target->may_need_copy_reloc(gsym))
+ {
+ target->copy_reloc(symtab, layout, object,
+ data_shndx, output_section, gsym, reloc);
+ }
+ else
+ {
+ check_non_pic(object, r_type);
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ rel_dyn->add_global(gsym, r_type, output_section, object,
+ data_shndx, reloc.get_r_offset());
+ }
+ }
+ }
+ break;
+
+ case elfcpp::R_ARM_PC24:
+ case elfcpp::R_ARM_THM_CALL:
+ case elfcpp::R_ARM_PLT32:
+ case elfcpp::R_ARM_CALL:
+ case elfcpp::R_ARM_JUMP24:
+ case elfcpp::R_ARM_THM_JUMP24:
+ case elfcpp::R_ARM_SBREL31:
+ case elfcpp::R_ARM_PREL31:
+ case elfcpp::R_ARM_THM_JUMP19:
+ case elfcpp::R_ARM_THM_JUMP6:
+ case elfcpp::R_ARM_THM_JUMP11:
+ case elfcpp::R_ARM_THM_JUMP8:
+ // All the relocation above are branches except for the PREL31 ones.
+ // A PREL31 relocation can point to a personality function in a shared
+ // library. In that case we want to use a PLT because we want to
+ // call the personality routine and the dyanmic linkers we care about
+ // do not support dynamic PREL31 relocations. An REL31 relocation may
+ // point to a function whose unwinding behaviour is being described but
+ // we will not mistakenly generate a PLT for that because we should use
+ // a local section symbol.
+
+ // If the symbol is fully resolved, this is just a relative
+ // local reloc. Otherwise we need a PLT entry.
+ if (gsym->final_value_is_known())
+ break;
+ // If building a shared library, we can also skip the PLT entry
+ // if the symbol is defined in the output file and is protected
+ // or hidden.
+ if (gsym->is_defined()
+ && !gsym->is_from_dynobj()
+ && !gsym->is_preemptible())
+ break;
+ target->make_plt_entry(symtab, layout, gsym);
+ break;
+
+ case elfcpp::R_ARM_GOT_BREL:
+ case elfcpp::R_ARM_GOT_ABS:
+ case elfcpp::R_ARM_GOT_PREL:
+ {
+ // The symbol requires a GOT entry.
+ Arm_output_data_got<big_endian>* got =
+ target->got_section(symtab, layout);
+ if (gsym->final_value_is_known())
+ got->add_global(gsym, GOT_TYPE_STANDARD);
+ else
+ {
+ // If this symbol is not fully resolved, we need to add a
+ // GOT entry with a dynamic relocation.
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ if (gsym->is_from_dynobj()
+ || gsym->is_undefined()
+ || gsym->is_preemptible())
+ got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
+ rel_dyn, elfcpp::R_ARM_GLOB_DAT);
+ else
+ {
+ if (got->add_global(gsym, GOT_TYPE_STANDARD))
+ rel_dyn->add_global_relative(
+ gsym, elfcpp::R_ARM_RELATIVE, got,
+ gsym->got_offset(GOT_TYPE_STANDARD));
+ }
+ }
+ }
+ break;
+
+ case elfcpp::R_ARM_TARGET1:
+ case elfcpp::R_ARM_TARGET2:
+ // These should have been mapped to other types already.
+ // Fall through.
+ case elfcpp::R_ARM_COPY:
+ case elfcpp::R_ARM_GLOB_DAT:
+ case elfcpp::R_ARM_JUMP_SLOT:
+ case elfcpp::R_ARM_RELATIVE:
+ // These are relocations which should only be seen by the
+ // dynamic linker, and should never be seen here.
+ gold_error(_("%s: unexpected reloc %u in object file"),
+ object->name().c_str(), r_type);
+ break;
+
+ // These are initial tls relocs, which are expected when
+ // linking.
+ case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
+ case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
+ case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
+ case elfcpp::R_ARM_TLS_IE32: // Initial-exec
+ case elfcpp::R_ARM_TLS_LE32: // Local-exec
+ {
+ const bool is_final = gsym->final_value_is_known();
+ const tls::Tls_optimization optimized_type
+ = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
+ switch (r_type)
+ {
+ case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
+ if (optimized_type == tls::TLSOPT_NONE)
+ {
+ // Create a pair of GOT entries for the module index and
+ // dtv-relative offset.
+ Arm_output_data_got<big_endian>* got
+ = target->got_section(symtab, layout);
+ if (!parameters->doing_static_link())
+ got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
+ target->rel_dyn_section(layout),
+ elfcpp::R_ARM_TLS_DTPMOD32,
+ elfcpp::R_ARM_TLS_DTPOFF32);
+ else
+ got->add_tls_gd32_with_static_reloc(GOT_TYPE_TLS_PAIR, gsym);
+ }
+ else
+ // FIXME: TLS optimization not supported yet.
+ gold_unreachable();
+ break;
+
+ case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
+ if (optimized_type == tls::TLSOPT_NONE)
+ {
+ // Create a GOT entry for the module index.
+ target->got_mod_index_entry(symtab, layout, object);
+ }
+ else
+ // FIXME: TLS optimization not supported yet.
+ gold_unreachable();
+ break;
+
+ case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
+ break;
+
+ case elfcpp::R_ARM_TLS_IE32: // Initial-exec
+ layout->set_has_static_tls();
+ if (optimized_type == tls::TLSOPT_NONE)
+ {
+ // Create a GOT entry for the tp-relative offset.
+ Arm_output_data_got<big_endian>* got
+ = target->got_section(symtab, layout);
+ if (!parameters->doing_static_link())
+ got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
+ target->rel_dyn_section(layout),
+ elfcpp::R_ARM_TLS_TPOFF32);
+ else if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
+ {
+ got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
+ unsigned int got_offset =
+ gsym->got_offset(GOT_TYPE_TLS_OFFSET);
+ got->add_static_reloc(got_offset,
+ elfcpp::R_ARM_TLS_TPOFF32, gsym);
+ }
+ }
+ else
+ // FIXME: TLS optimization not supported yet.
+ gold_unreachable();
+ break;
+
+ case elfcpp::R_ARM_TLS_LE32: // Local-exec
+ layout->set_has_static_tls();
+ if (parameters->options().shared())
+ {
+ // We need to create a dynamic relocation.
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ rel_dyn->add_global(gsym, elfcpp::R_ARM_TLS_TPOFF32,
+ output_section, object,
+ data_shndx, reloc.get_r_offset());
+ }
+ break;
+
+ default:
+ gold_unreachable();
+ }
+ }
+ break;
+
+ default:
+ unsupported_reloc_global(object, r_type, gsym);
+ break;
+ }
+}
+
+// Process relocations for gc.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::gc_process_relocs(Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ unsigned int,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ size_t local_symbol_count,
+ const unsigned char* plocal_symbols)
+{
+ typedef Target_arm<big_endian> Arm;
+ typedef typename Target_arm<big_endian>::Scan Scan;
+
+ gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>(
+ symtab,
+ layout,
+ this,
+ object,
+ data_shndx,
+ prelocs,
+ reloc_count,
+ output_section,
+ needs_special_offset_handling,
+ local_symbol_count,
+ plocal_symbols);
+}
+
+// Scan relocations for a section.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::scan_relocs(Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ size_t local_symbol_count,
+ const unsigned char* plocal_symbols)
+{
+ typedef typename Target_arm<big_endian>::Scan Scan;
+ if (sh_type == elfcpp::SHT_RELA)
+ {
+ gold_error(_("%s: unsupported RELA reloc section"),
+ object->name().c_str());
+ return;
+ }
+
+ gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
+ symtab,
+ layout,
+ this,
+ object,
+ data_shndx,
+ prelocs,
+ reloc_count,
+ output_section,
+ needs_special_offset_handling,
+ local_symbol_count,
+ plocal_symbols);
+}
+
+// Finalize the sections.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::do_finalize_sections(
+ Layout* layout,
+ const Input_objects* input_objects,
+ Symbol_table* symtab)
+{
+ bool merged_any_attributes = false;
+ // Merge processor-specific flags.
+ for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
+ p != input_objects->relobj_end();
+ ++p)
+ {
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(*p);
+ if (arm_relobj->merge_flags_and_attributes())
+ {
+ this->merge_processor_specific_flags(
+ arm_relobj->name(),
+ arm_relobj->processor_specific_flags());
+ this->merge_object_attributes(arm_relobj->name().c_str(),
+ arm_relobj->attributes_section_data());
+ merged_any_attributes = true;
}
+ }
+
+ for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
+ p != input_objects->dynobj_end();
+ ++p)
+ {
+ Arm_dynobj<big_endian>* arm_dynobj =
+ Arm_dynobj<big_endian>::as_arm_dynobj(*p);
+ this->merge_processor_specific_flags(
+ arm_dynobj->name(),
+ arm_dynobj->processor_specific_flags());
+ this->merge_object_attributes(arm_dynobj->name().c_str(),
+ arm_dynobj->attributes_section_data());
+ merged_any_attributes = true;
}
- return stub_type;
-}
+ // Create an empty uninitialized attribute section if we still don't have it
+ // at this moment. This happens if there is no attributes sections in all
+ // inputs.
+ if (this->attributes_section_data_ == NULL)
+ this->attributes_section_data_ = new Attributes_section_data(NULL, 0);
+
+ // Check BLX use.
+ const Object_attribute* cpu_arch_attr =
+ this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch);
+ if (cpu_arch_attr->int_value() > elfcpp::TAG_CPU_ARCH_V4)
+ this->set_may_use_blx(true);
+
+ // Check if we need to use Cortex-A8 workaround.
+ if (parameters->options().user_set_fix_cortex_a8())
+ this->fix_cortex_a8_ = parameters->options().fix_cortex_a8();
+ else
+ {
+ // If neither --fix-cortex-a8 nor --no-fix-cortex-a8 is used, turn on
+ // Cortex-A8 erratum workaround for ARMv7-A or ARMv7 with unknown
+ // profile.
+ const Object_attribute* cpu_arch_profile_attr =
+ this->get_aeabi_object_attribute(elfcpp::Tag_CPU_arch_profile);
+ this->fix_cortex_a8_ =
+ (cpu_arch_attr->int_value() == elfcpp::TAG_CPU_ARCH_V7
+ && (cpu_arch_profile_attr->int_value() == 'A'
+ || cpu_arch_profile_attr->int_value() == 0));
+ }
+
+ // Check if we can use V4BX interworking.
+ // The V4BX interworking stub contains BX instruction,
+ // which is not specified for some profiles.
+ if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING
+ && !this->may_use_blx())
+ gold_error(_("unable to provide V4BX reloc interworking fix up; "
+ "the target profile does not support BX instruction"));
-// Template to implement do_write for a specific target endianity.
+ // Fill in some more dynamic tags.
+ const Reloc_section* rel_plt = (this->plt_ == NULL
+ ? NULL
+ : this->plt_->rel_plt());
+ layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
+ this->rel_dyn_, true, false);
-template<bool big_endian>
-void inline
-Reloc_stub::do_fixed_endian_write(unsigned char* view,
- section_size_type view_size)
-{
- const Stub_template* stub_template = this->stub_template();
- const Insn_template* insns = stub_template->insns();
+ // Emit any relocs we saved in an attempt to avoid generating COPY
+ // relocs.
+ if (this->copy_relocs_.any_saved_relocs())
+ this->copy_relocs_.emit(this->rel_dyn_section(layout));
- // FIXME: We do not handle BE8 encoding yet.
- unsigned char* pov = view;
- for (size_t i = 0; i < stub_template->insn_count(); i++)
+ // Handle the .ARM.exidx section.
+ Output_section* exidx_section = layout->find_output_section(".ARM.exidx");
+ if (exidx_section != NULL
+ && exidx_section->type() == elfcpp::SHT_ARM_EXIDX
+ && !parameters->options().relocatable())
{
- switch (insns[i].type())
+ // Create __exidx_start and __exdix_end symbols.
+ symtab->define_in_output_data("__exidx_start", NULL,
+ Symbol_table::PREDEFINED,
+ exidx_section, 0, 0, elfcpp::STT_OBJECT,
+ elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
+ false, true);
+ symtab->define_in_output_data("__exidx_end", NULL,
+ Symbol_table::PREDEFINED,
+ exidx_section, 0, 0, elfcpp::STT_OBJECT,
+ elfcpp::STB_GLOBAL, elfcpp::STV_HIDDEN, 0,
+ true, true);
+
+ // For the ARM target, we need to add a PT_ARM_EXIDX segment for
+ // the .ARM.exidx section.
+ if (!layout->script_options()->saw_phdrs_clause())
{
- case Insn_template::THUMB16_TYPE:
- // Non-zero reloc addends are only used in Cortex-A8 stubs.
- gold_assert(insns[i].reloc_addend() == 0);
- elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
- break;
- case Insn_template::THUMB32_TYPE:
- {
- uint32_t hi = (insns[i].data() >> 16) & 0xffff;
- uint32_t lo = insns[i].data() & 0xffff;
- elfcpp::Swap<16, big_endian>::writeval(pov, hi);
- elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
- }
- break;
- case Insn_template::ARM_TYPE:
- case Insn_template::DATA_TYPE:
- elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
- break;
- default:
- gold_unreachable();
+ gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0)
+ == NULL);
+ Output_segment* exidx_segment =
+ layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
+ exidx_segment->add_output_section(exidx_section, elfcpp::PF_R,
+ false);
}
- pov += insns[i].size();
}
- gold_assert(static_cast<section_size_type>(pov - view) == view_size);
-}
-// Write a reloc stub to VIEW with endianity specified by BIG_ENDIAN.
+ // Create an .ARM.attributes section if we have merged any attributes
+ // from inputs.
+ if (merged_any_attributes)
+ {
+ Output_attributes_section_data* attributes_section =
+ new Output_attributes_section_data(*this->attributes_section_data_);
+ layout->add_output_section_data(".ARM.attributes",
+ elfcpp::SHT_ARM_ATTRIBUTES, 0,
+ attributes_section, false, false, false,
+ false);
+ }
-void
-Reloc_stub::do_write(unsigned char* view, section_size_type view_size,
- bool big_endian)
+ // Fix up links in section EXIDX headers.
+ for (Layout::Section_list::const_iterator p = layout->section_list().begin();
+ p != layout->section_list().end();
+ ++p)
+ if ((*p)->type() == elfcpp::SHT_ARM_EXIDX)
+ {
+ Arm_output_section<big_endian>* os =
+ Arm_output_section<big_endian>::as_arm_output_section(*p);
+ os->set_exidx_section_link();
+ }
+}
+
+// Return whether a direct absolute static relocation needs to be applied.
+// In cases where Scan::local() or Scan::global() has created
+// a dynamic relocation other than R_ARM_RELATIVE, the addend
+// of the relocation is carried in the data, and we must not
+// apply the static relocation.
+
+template<bool big_endian>
+inline bool
+Target_arm<big_endian>::Relocate::should_apply_static_reloc(
+ const Sized_symbol<32>* gsym,
+ int ref_flags,
+ bool is_32bit,
+ Output_section* output_section)
{
- if (big_endian)
- this->do_fixed_endian_write<true>(view, view_size);
- else
- this->do_fixed_endian_write<false>(view, view_size);
+ // If the output section is not allocated, then we didn't call
+ // scan_relocs, we didn't create a dynamic reloc, and we must apply
+ // the reloc here.
+ if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
+ return true;
+
+ // For local symbols, we will have created a non-RELATIVE dynamic
+ // relocation only if (a) the output is position independent,
+ // (b) the relocation is absolute (not pc- or segment-relative), and
+ // (c) the relocation is not 32 bits wide.
+ if (gsym == NULL)
+ return !(parameters->options().output_is_position_independent()
+ && (ref_flags & Symbol::ABSOLUTE_REF)
+ && !is_32bit);
+
+ // For global symbols, we use the same helper routines used in the
+ // scan pass. If we did not create a dynamic relocation, or if we
+ // created a RELATIVE dynamic relocation, we should apply the static
+ // relocation.
+ bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
+ bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
+ && gsym->can_use_relative_reloc(ref_flags
+ & Symbol::FUNCTION_CALL);
+ return !has_dyn || is_rel;
}
-// Stub_factory methods.
+// Perform a relocation.
-Stub_factory::Stub_factory()
+template<bool big_endian>
+inline bool
+Target_arm<big_endian>::Relocate::relocate(
+ const Relocate_info<32, big_endian>* relinfo,
+ Target_arm* target,
+ Output_section *output_section,
+ size_t relnum,
+ const elfcpp::Rel<32, big_endian>& rel,
+ unsigned int r_type,
+ const Sized_symbol<32>* gsym,
+ const Symbol_value<32>* psymval,
+ unsigned char* view,
+ Arm_address address,
+ section_size_type view_size)
{
- // The instruction template sequences are declared as static
- // objects and initialized first time the constructor runs.
-
- // Arm/Thumb -> Arm/Thumb long branch stub. On V5T and above, use blx
- // to reach the stub if necessary.
- static const Insn_template elf32_arm_stub_long_branch_any_any[] =
- {
- Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
- Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
- // dcd R_ARM_ABS32(X)
- };
-
- // V4T Arm -> Thumb long branch stub. Used on V4T where blx is not
- // available.
- static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb[] =
- {
- Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
- Insn_template::arm_insn(0xe12fff1c), // bx ip
- Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
- // dcd R_ARM_ABS32(X)
- };
-
- // Thumb -> Thumb long branch stub. Used on M-profile architectures.
- static const Insn_template elf32_arm_stub_long_branch_thumb_only[] =
- {
- Insn_template::thumb16_insn(0xb401), // push {r0}
- Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
- Insn_template::thumb16_insn(0x4684), // mov ip, r0
- Insn_template::thumb16_insn(0xbc01), // pop {r0}
- Insn_template::thumb16_insn(0x4760), // bx ip
- Insn_template::thumb16_insn(0xbf00), // nop
- Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
- // dcd R_ARM_ABS32(X)
- };
-
- // V4T Thumb -> Thumb long branch stub. Using the stack is not
- // allowed.
- static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb[] =
- {
- Insn_template::thumb16_insn(0x4778), // bx pc
- Insn_template::thumb16_insn(0x46c0), // nop
- Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
- Insn_template::arm_insn(0xe12fff1c), // bx ip
- Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
- // dcd R_ARM_ABS32(X)
- };
-
- // V4T Thumb -> ARM long branch stub. Used on V4T where blx is not
- // available.
- static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm[] =
- {
- Insn_template::thumb16_insn(0x4778), // bx pc
- Insn_template::thumb16_insn(0x46c0), // nop
- Insn_template::arm_insn(0xe51ff004), // ldr pc, [pc, #-4]
- Insn_template::data_word(0, elfcpp::R_ARM_ABS32, 0),
- // dcd R_ARM_ABS32(X)
- };
-
- // V4T Thumb -> ARM short branch stub. Shorter variant of the above
- // one, when the destination is close enough.
- static const Insn_template elf32_arm_stub_short_branch_v4t_thumb_arm[] =
- {
- Insn_template::thumb16_insn(0x4778), // bx pc
- Insn_template::thumb16_insn(0x46c0), // nop
- Insn_template::arm_rel_insn(0xea000000, -8), // b (X-8)
- };
-
- // ARM/Thumb -> ARM long branch stub, PIC. On V5T and above, use
- // blx to reach the stub if necessary.
- static const Insn_template elf32_arm_stub_long_branch_any_arm_pic[] =
- {
- Insn_template::arm_insn(0xe59fc000), // ldr r12, [pc]
- Insn_template::arm_insn(0xe08ff00c), // add pc, pc, ip
- Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
- // dcd R_ARM_REL32(X-4)
- };
-
- // ARM/Thumb -> Thumb long branch stub, PIC. On V5T and above, use
- // blx to reach the stub if necessary. We can not add into pc;
- // it is not guaranteed to mode switch (different in ARMv6 and
- // ARMv7).
- static const Insn_template elf32_arm_stub_long_branch_any_thumb_pic[] =
- {
- Insn_template::arm_insn(0xe59fc004), // ldr r12, [pc, #4]
- Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
- Insn_template::arm_insn(0xe12fff1c), // bx ip
- Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
- // dcd R_ARM_REL32(X)
- };
-
- // V4T ARM -> ARM long branch stub, PIC.
- static const Insn_template elf32_arm_stub_long_branch_v4t_arm_thumb_pic[] =
- {
- Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
- Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
- Insn_template::arm_insn(0xe12fff1c), // bx ip
- Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
- // dcd R_ARM_REL32(X)
- };
-
- // V4T Thumb -> ARM long branch stub, PIC.
- static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_arm_pic[] =
+ typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
+
+ r_type = get_real_reloc_type(r_type);
+ const Arm_reloc_property* reloc_property =
+ arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
+ if (reloc_property == NULL)
{
- Insn_template::thumb16_insn(0x4778), // bx pc
- Insn_template::thumb16_insn(0x46c0), // nop
- Insn_template::arm_insn(0xe59fc000), // ldr ip, [pc, #0]
- Insn_template::arm_insn(0xe08cf00f), // add pc, ip, pc
- Insn_template::data_word(0, elfcpp::R_ARM_REL32, -4),
- // dcd R_ARM_REL32(X)
- };
-
- // Thumb -> Thumb long branch stub, PIC. Used on M-profile
- // architectures.
- static const Insn_template elf32_arm_stub_long_branch_thumb_only_pic[] =
+ std::string reloc_name =
+ arm_reloc_property_table->reloc_name_in_error_message(r_type);
+ gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
+ _("cannot relocate %s in object file"),
+ reloc_name.c_str());
+ return true;
+ }
+
+ const Arm_relobj<big_endian>* object =
+ Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
+
+ // If the final branch target of a relocation is THUMB instruction, this
+ // is 1. Otherwise it is 0.
+ Arm_address thumb_bit = 0;
+ Symbol_value<32> symval;
+ bool is_weakly_undefined_without_plt = false;
+ if (relnum != Target_arm<big_endian>::fake_relnum_for_stubs)
{
- Insn_template::thumb16_insn(0xb401), // push {r0}
- Insn_template::thumb16_insn(0x4802), // ldr r0, [pc, #8]
- Insn_template::thumb16_insn(0x46fc), // mov ip, pc
- Insn_template::thumb16_insn(0x4484), // add ip, r0
- Insn_template::thumb16_insn(0xbc01), // pop {r0}
- Insn_template::thumb16_insn(0x4760), // bx ip
- Insn_template::data_word(0, elfcpp::R_ARM_REL32, 4),
- // dcd R_ARM_REL32(X)
- };
-
- // V4T Thumb -> Thumb long branch stub, PIC. Using the stack is not
- // allowed.
- static const Insn_template elf32_arm_stub_long_branch_v4t_thumb_thumb_pic[] =
+ if (gsym != NULL)
+ {
+ // This is a global symbol. Determine if we use PLT and if the
+ // final target is THUMB.
+ if (gsym->use_plt_offset(reloc_is_non_pic(r_type)))
+ {
+ // This uses a PLT, change the symbol value.
+ symval.set_output_value(target->plt_section()->address()
+ + gsym->plt_offset());
+ psymval = &symval;
+ }
+ else if (gsym->is_weak_undefined())
+ {
+ // This is a weakly undefined symbol and we do not use PLT
+ // for this relocation. A branch targeting this symbol will
+ // be converted into an NOP.
+ is_weakly_undefined_without_plt = true;
+ }
+ else if (gsym->is_undefined() && reloc_property->uses_symbol())
+ {
+ // This relocation uses the symbol value but the symbol is
+ // undefined. Exit early and have the caller reporting an
+ // error.
+ return true;
+ }
+ else
+ {
+ // Set thumb bit if symbol:
+ // -Has type STT_ARM_TFUNC or
+ // -Has type STT_FUNC, is defined and with LSB in value set.
+ thumb_bit =
+ (((gsym->type() == elfcpp::STT_ARM_TFUNC)
+ || (gsym->type() == elfcpp::STT_FUNC
+ && !gsym->is_undefined()
+ && ((psymval->value(object, 0) & 1) != 0)))
+ ? 1
+ : 0);
+ }
+ }
+ else
+ {
+ // This is a local symbol. Determine if the final target is THUMB.
+ // We saved this information when all the local symbols were read.
+ elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info();
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
+ thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
+ }
+ }
+ else
{
- Insn_template::thumb16_insn(0x4778), // bx pc
- Insn_template::thumb16_insn(0x46c0), // nop
- Insn_template::arm_insn(0xe59fc004), // ldr ip, [pc, #4]
- Insn_template::arm_insn(0xe08fc00c), // add ip, pc, ip
- Insn_template::arm_insn(0xe12fff1c), // bx ip
- Insn_template::data_word(0, elfcpp::R_ARM_REL32, 0),
- // dcd R_ARM_REL32(X)
- };
-
- // Cortex-A8 erratum-workaround stubs.
-
- // Stub used for conditional branches (which may be beyond +/-1MB away,
- // so we can't use a conditional branch to reach this stub).
-
- // original code:
- //
- // b<cond> X
- // after:
- //
- static const Insn_template elf32_arm_stub_a8_veneer_b_cond[] =
+ // This is a fake relocation synthesized for a stub. It does not have
+ // a real symbol. We just look at the LSB of the symbol value to
+ // determine if the target is THUMB or not.
+ thumb_bit = ((psymval->value(object, 0) & 1) != 0);
+ }
+
+ // Strip LSB if this points to a THUMB target.
+ if (thumb_bit != 0
+ && reloc_property->uses_thumb_bit()
+ && ((psymval->value(object, 0) & 1) != 0))
{
- Insn_template::thumb16_bcond_insn(0xd001), // b<cond>.n true
- Insn_template::thumb32_b_insn(0xf000b800, -4), // b.w after
- Insn_template::thumb32_b_insn(0xf000b800, -4) // true:
- // b.w X
- };
-
- // Stub used for b.w and bl.w instructions.
-
- static const Insn_template elf32_arm_stub_a8_veneer_b[] =
+ Arm_address stripped_value =
+ psymval->value(object, 0) & ~static_cast<Arm_address>(1);
+ symval.set_output_value(stripped_value);
+ psymval = &symval;
+ }
+
+ // Get the GOT offset if needed.
+ // The GOT pointer points to the end of the GOT section.
+ // We need to subtract the size of the GOT section to get
+ // the actual offset to use in the relocation.
+ bool have_got_offset = false;
+ unsigned int got_offset = 0;
+ switch (r_type)
{
- Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
- };
-
- static const Insn_template elf32_arm_stub_a8_veneer_bl[] =
+ case elfcpp::R_ARM_GOT_BREL:
+ case elfcpp::R_ARM_GOT_PREL:
+ if (gsym != NULL)
+ {
+ gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
+ got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
+ - target->got_size());
+ }
+ else
+ {
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
+ gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
+ got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
+ - target->got_size());
+ }
+ have_got_offset = true;
+ break;
+
+ default:
+ break;
+ }
+
+ // To look up relocation stubs, we need to pass the symbol table index of
+ // a local symbol.
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
+
+ // Get the addressing origin of the output segment defining the
+ // symbol gsym if needed (AAELF 4.6.1.2 Relocation types).
+ Arm_address sym_origin = 0;
+ if (reloc_property->uses_symbol_base())
{
- Insn_template::thumb32_b_insn(0xf000b800, -4) // b.w dest
- };
-
- // Stub used for Thumb-2 blx.w instructions. We modified the original blx.w
- // instruction (which switches to ARM mode) to point to this stub. Jump to
- // the real destination using an ARM-mode branch.
- const Insn_template elf32_arm_stub_a8_veneer_blx[] =
+ if (r_type == elfcpp::R_ARM_BASE_ABS && gsym == NULL)
+ // R_ARM_BASE_ABS with the NULL symbol will give the
+ // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
+ // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
+ sym_origin = target->got_plt_section()->address();
+ else if (gsym == NULL)
+ sym_origin = 0;
+ else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
+ sym_origin = gsym->output_segment()->vaddr();
+ else if (gsym->source() == Symbol::IN_OUTPUT_DATA)
+ sym_origin = gsym->output_data()->address();
+
+ // TODO: Assumes the segment base to be zero for the global symbols
+ // till the proper support for the segment-base-relative addressing
+ // will be implemented. This is consistent with GNU ld.
+ }
+
+ // For relative addressing relocation, find out the relative address base.
+ Arm_address relative_address_base = 0;
+ switch(reloc_property->relative_address_base())
{
- Insn_template::arm_rel_insn(0xea000000, -8) // b dest
- };
+ case Arm_reloc_property::RAB_NONE:
+ // Relocations with relative address bases RAB_TLS and RAB_tp are
+ // handled by relocate_tls. So we do not need to do anything here.
+ case Arm_reloc_property::RAB_TLS:
+ case Arm_reloc_property::RAB_tp:
+ break;
+ case Arm_reloc_property::RAB_B_S:
+ relative_address_base = sym_origin;
+ break;
+ case Arm_reloc_property::RAB_GOT_ORG:
+ relative_address_base = target->got_plt_section()->address();
+ break;
+ case Arm_reloc_property::RAB_P:
+ relative_address_base = address;
+ break;
+ case Arm_reloc_property::RAB_Pa:
+ relative_address_base = address & 0xfffffffcU;
+ break;
+ default:
+ gold_unreachable();
+ }
+
+ typename Arm_relocate_functions::Status reloc_status =
+ Arm_relocate_functions::STATUS_OKAY;
+ bool check_overflow = reloc_property->checks_overflow();
+ switch (r_type)
+ {
+ case elfcpp::R_ARM_NONE:
+ break;
- // Fill in the stub template look-up table. Stub templates are constructed
- // per instance of Stub_factory for fast look-up without locking
- // in a thread-enabled environment.
+ case elfcpp::R_ARM_ABS8:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
+ output_section))
+ reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
+ break;
- this->stub_templates_[arm_stub_none] =
- new Stub_template(arm_stub_none, NULL, 0);
+ case elfcpp::R_ARM_ABS12:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
+ output_section))
+ reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
+ break;
-#define DEF_STUB(x) \
- do \
- { \
- size_t array_size \
- = sizeof(elf32_arm_stub_##x) / sizeof(elf32_arm_stub_##x[0]); \
- Stub_type type = arm_stub_##x; \
- this->stub_templates_[type] = \
- new Stub_template(type, elf32_arm_stub_##x, array_size); \
- } \
- while (0);
+ case elfcpp::R_ARM_ABS16:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
+ output_section))
+ reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
+ break;
- DEF_STUBS
-#undef DEF_STUB
-}
+ case elfcpp::R_ARM_ABS32:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
+ output_section))
+ reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
+ thumb_bit);
+ break;
-// A class to handle the PLT data.
+ case elfcpp::R_ARM_ABS32_NOI:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
+ output_section))
+ // No thumb bit for this relocation: (S + A)
+ reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
+ 0);
+ break;
-template<bool big_endian>
-class Output_data_plt_arm : public Output_section_data
-{
- public:
- typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
- Reloc_section;
+ case elfcpp::R_ARM_MOVW_ABS_NC:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
+ output_section))
+ reloc_status = Arm_relocate_functions::movw(view, object, psymval,
+ 0, thumb_bit,
+ check_overflow);
+ break;
- Output_data_plt_arm(Layout*, Output_data_space*);
+ case elfcpp::R_ARM_MOVT_ABS:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
+ output_section))
+ reloc_status = Arm_relocate_functions::movt(view, object, psymval, 0);
+ break;
- // Add an entry to the PLT.
- void
- add_entry(Symbol* gsym);
+ case elfcpp::R_ARM_THM_MOVW_ABS_NC:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
+ output_section))
+ reloc_status = Arm_relocate_functions::thm_movw(view, object, psymval,
+ 0, thumb_bit, false);
+ break;
+
+ case elfcpp::R_ARM_THM_MOVT_ABS:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
+ output_section))
+ reloc_status = Arm_relocate_functions::thm_movt(view, object,
+ psymval, 0);
+ break;
+
+ case elfcpp::R_ARM_MOVW_PREL_NC:
+ case elfcpp::R_ARM_MOVW_BREL_NC:
+ case elfcpp::R_ARM_MOVW_BREL:
+ reloc_status =
+ Arm_relocate_functions::movw(view, object, psymval,
+ relative_address_base, thumb_bit,
+ check_overflow);
+ break;
+
+ case elfcpp::R_ARM_MOVT_PREL:
+ case elfcpp::R_ARM_MOVT_BREL:
+ reloc_status =
+ Arm_relocate_functions::movt(view, object, psymval,
+ relative_address_base);
+ break;
+
+ case elfcpp::R_ARM_THM_MOVW_PREL_NC:
+ case elfcpp::R_ARM_THM_MOVW_BREL_NC:
+ case elfcpp::R_ARM_THM_MOVW_BREL:
+ reloc_status =
+ Arm_relocate_functions::thm_movw(view, object, psymval,
+ relative_address_base,
+ thumb_bit, check_overflow);
+ break;
+
+ case elfcpp::R_ARM_THM_MOVT_PREL:
+ case elfcpp::R_ARM_THM_MOVT_BREL:
+ reloc_status =
+ Arm_relocate_functions::thm_movt(view, object, psymval,
+ relative_address_base);
+ break;
+
+ case elfcpp::R_ARM_REL32:
+ reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
+ address, thumb_bit);
+ break;
+
+ case elfcpp::R_ARM_THM_ABS5:
+ if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
+ output_section))
+ reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
+ break;
+
+ // Thumb long branches.
+ case elfcpp::R_ARM_THM_CALL:
+ case elfcpp::R_ARM_THM_XPC22:
+ case elfcpp::R_ARM_THM_JUMP24:
+ reloc_status =
+ Arm_relocate_functions::thumb_branch_common(
+ r_type, relinfo, view, gsym, object, r_sym, psymval, address,
+ thumb_bit, is_weakly_undefined_without_plt);
+ break;
+
+ case elfcpp::R_ARM_GOTOFF32:
+ {
+ Arm_address got_origin;
+ got_origin = target->got_plt_section()->address();
+ reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
+ got_origin, thumb_bit);
+ }
+ break;
+
+ case elfcpp::R_ARM_BASE_PREL:
+ gold_assert(gsym != NULL);
+ reloc_status =
+ Arm_relocate_functions::base_prel(view, sym_origin, address);
+ break;
+
+ case elfcpp::R_ARM_BASE_ABS:
+ {
+ if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
+ output_section))
+ break;
+
+ reloc_status = Arm_relocate_functions::base_abs(view, sym_origin);
+ }
+ break;
+
+ case elfcpp::R_ARM_GOT_BREL:
+ gold_assert(have_got_offset);
+ reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
+ break;
+
+ case elfcpp::R_ARM_GOT_PREL:
+ gold_assert(have_got_offset);
+ // Get the address origin for GOT PLT, which is allocated right
+ // after the GOT section, to calculate an absolute address of
+ // the symbol GOT entry (got_origin + got_offset).
+ Arm_address got_origin;
+ got_origin = target->got_plt_section()->address();
+ reloc_status = Arm_relocate_functions::got_prel(view,
+ got_origin + got_offset,
+ address);
+ break;
+
+ case elfcpp::R_ARM_PLT32:
+ case elfcpp::R_ARM_CALL:
+ case elfcpp::R_ARM_JUMP24:
+ case elfcpp::R_ARM_XPC25:
+ gold_assert(gsym == NULL
+ || gsym->has_plt_offset()
+ || gsym->final_value_is_known()
+ || (gsym->is_defined()
+ && !gsym->is_from_dynobj()
+ && !gsym->is_preemptible()));
+ reloc_status =
+ Arm_relocate_functions::arm_branch_common(
+ r_type, relinfo, view, gsym, object, r_sym, psymval, address,
+ thumb_bit, is_weakly_undefined_without_plt);
+ break;
+
+ case elfcpp::R_ARM_THM_JUMP19:
+ reloc_status =
+ Arm_relocate_functions::thm_jump19(view, object, psymval, address,
+ thumb_bit);
+ break;
+
+ case elfcpp::R_ARM_THM_JUMP6:
+ reloc_status =
+ Arm_relocate_functions::thm_jump6(view, object, psymval, address);
+ break;
+
+ case elfcpp::R_ARM_THM_JUMP8:
+ reloc_status =
+ Arm_relocate_functions::thm_jump8(view, object, psymval, address);
+ break;
+
+ case elfcpp::R_ARM_THM_JUMP11:
+ reloc_status =
+ Arm_relocate_functions::thm_jump11(view, object, psymval, address);
+ break;
+
+ case elfcpp::R_ARM_PREL31:
+ reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
+ address, thumb_bit);
+ break;
+
+ case elfcpp::R_ARM_V4BX:
+ if (target->fix_v4bx() > General_options::FIX_V4BX_NONE)
+ {
+ const bool is_v4bx_interworking =
+ (target->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING);
+ reloc_status =
+ Arm_relocate_functions::v4bx(relinfo, view, object, address,
+ is_v4bx_interworking);
+ }
+ break;
- // Return the .rel.plt section data.
- const Reloc_section*
- rel_plt() const
- { return this->rel_; }
+ case elfcpp::R_ARM_THM_PC8:
+ reloc_status =
+ Arm_relocate_functions::thm_pc8(view, object, psymval, address);
+ break;
- protected:
- void
- do_adjust_output_section(Output_section* os);
+ case elfcpp::R_ARM_THM_PC12:
+ reloc_status =
+ Arm_relocate_functions::thm_pc12(view, object, psymval, address);
+ break;
- // Write to a map file.
- void
- do_print_to_mapfile(Mapfile* mapfile) const
- { mapfile->print_output_data(this, _("** PLT")); }
+ case elfcpp::R_ARM_THM_ALU_PREL_11_0:
+ reloc_status =
+ Arm_relocate_functions::thm_alu11(view, object, psymval, address,
+ thumb_bit);
+ break;
- private:
- // Template for the first PLT entry.
- static const uint32_t first_plt_entry[5];
+ case elfcpp::R_ARM_ALU_PC_G0_NC:
+ case elfcpp::R_ARM_ALU_PC_G0:
+ case elfcpp::R_ARM_ALU_PC_G1_NC:
+ case elfcpp::R_ARM_ALU_PC_G1:
+ case elfcpp::R_ARM_ALU_PC_G2:
+ case elfcpp::R_ARM_ALU_SB_G0_NC:
+ case elfcpp::R_ARM_ALU_SB_G0:
+ case elfcpp::R_ARM_ALU_SB_G1_NC:
+ case elfcpp::R_ARM_ALU_SB_G1:
+ case elfcpp::R_ARM_ALU_SB_G2:
+ reloc_status =
+ Arm_relocate_functions::arm_grp_alu(view, object, psymval,
+ reloc_property->group_index(),
+ relative_address_base,
+ thumb_bit, check_overflow);
+ break;
- // Template for subsequent PLT entries.
- static const uint32_t plt_entry[3];
+ case elfcpp::R_ARM_LDR_PC_G0:
+ case elfcpp::R_ARM_LDR_PC_G1:
+ case elfcpp::R_ARM_LDR_PC_G2:
+ case elfcpp::R_ARM_LDR_SB_G0:
+ case elfcpp::R_ARM_LDR_SB_G1:
+ case elfcpp::R_ARM_LDR_SB_G2:
+ reloc_status =
+ Arm_relocate_functions::arm_grp_ldr(view, object, psymval,
+ reloc_property->group_index(),
+ relative_address_base);
+ break;
- // Set the final size.
- void
- set_final_data_size()
- {
- this->set_data_size(sizeof(first_plt_entry)
- + this->count_ * sizeof(plt_entry));
- }
+ case elfcpp::R_ARM_LDRS_PC_G0:
+ case elfcpp::R_ARM_LDRS_PC_G1:
+ case elfcpp::R_ARM_LDRS_PC_G2:
+ case elfcpp::R_ARM_LDRS_SB_G0:
+ case elfcpp::R_ARM_LDRS_SB_G1:
+ case elfcpp::R_ARM_LDRS_SB_G2:
+ reloc_status =
+ Arm_relocate_functions::arm_grp_ldrs(view, object, psymval,
+ reloc_property->group_index(),
+ relative_address_base);
+ break;
- // Write out the PLT data.
- void
- do_write(Output_file*);
+ case elfcpp::R_ARM_LDC_PC_G0:
+ case elfcpp::R_ARM_LDC_PC_G1:
+ case elfcpp::R_ARM_LDC_PC_G2:
+ case elfcpp::R_ARM_LDC_SB_G0:
+ case elfcpp::R_ARM_LDC_SB_G1:
+ case elfcpp::R_ARM_LDC_SB_G2:
+ reloc_status =
+ Arm_relocate_functions::arm_grp_ldc(view, object, psymval,
+ reloc_property->group_index(),
+ relative_address_base);
+ break;
- // The reloc section.
- Reloc_section* rel_;
- // The .got.plt section.
- Output_data_space* got_plt_;
- // The number of PLT entries.
- unsigned int count_;
-};
+ // These are initial tls relocs, which are expected when
+ // linking.
+ case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
+ case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
+ case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
+ case elfcpp::R_ARM_TLS_IE32: // Initial-exec
+ case elfcpp::R_ARM_TLS_LE32: // Local-exec
+ reloc_status =
+ this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
+ view, address, view_size);
+ break;
-// Create the PLT section. The ordinary .got section is an argument,
-// since we need to refer to the start. We also create our own .got
-// section just for PLT entries.
+ default:
+ gold_unreachable();
+ }
-template<bool big_endian>
-Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
- Output_data_space* got_plt)
- : Output_section_data(4), got_plt_(got_plt), count_(0)
-{
- this->rel_ = new Reloc_section(false);
- layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
- elfcpp::SHF_ALLOC, this->rel_);
-}
+ // Report any errors.
+ switch (reloc_status)
+ {
+ case Arm_relocate_functions::STATUS_OKAY:
+ break;
+ case Arm_relocate_functions::STATUS_OVERFLOW:
+ gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
+ _("relocation overflow in %s"),
+ reloc_property->name().c_str());
+ break;
+ case Arm_relocate_functions::STATUS_BAD_RELOC:
+ gold_error_at_location(
+ relinfo,
+ relnum,
+ rel.get_r_offset(),
+ _("unexpected opcode while processing relocation %s"),
+ reloc_property->name().c_str());
+ break;
+ default:
+ gold_unreachable();
+ }
-template<bool big_endian>
-void
-Output_data_plt_arm<big_endian>::do_adjust_output_section(Output_section* os)
-{
- os->set_entsize(0);
+ return true;
}
-// Add an entry to the PLT.
+// Perform a TLS relocation.
template<bool big_endian>
-void
-Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
+inline typename Arm_relocate_functions<big_endian>::Status
+Target_arm<big_endian>::Relocate::relocate_tls(
+ const Relocate_info<32, big_endian>* relinfo,
+ Target_arm<big_endian>* target,
+ size_t relnum,
+ const elfcpp::Rel<32, big_endian>& rel,
+ unsigned int r_type,
+ const Sized_symbol<32>* gsym,
+ const Symbol_value<32>* psymval,
+ unsigned char* view,
+ elfcpp::Elf_types<32>::Elf_Addr address,
+ section_size_type /*view_size*/ )
{
- gold_assert(!gsym->has_plt_offset());
-
- // Note that when setting the PLT offset we skip the initial
- // reserved PLT entry.
- gsym->set_plt_offset((this->count_) * sizeof(plt_entry)
- + sizeof(first_plt_entry));
+ typedef Arm_relocate_functions<big_endian> ArmRelocFuncs;
+ typedef Relocate_functions<32, big_endian> RelocFuncs;
+ Output_segment* tls_segment = relinfo->layout->tls_segment();
- ++this->count_;
+ const Sized_relobj<32, big_endian>* object = relinfo->object;
- section_offset_type got_offset = this->got_plt_->current_data_size();
+ elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
- // Every PLT entry needs a GOT entry which points back to the PLT
- // entry (this will be changed by the dynamic linker, normally
- // lazily when the function is called).
- this->got_plt_->set_current_data_size(got_offset + 4);
+ const bool is_final = (gsym == NULL
+ ? !parameters->options().shared()
+ : gsym->final_value_is_known());
+ const tls::Tls_optimization optimized_type
+ = Target_arm<big_endian>::optimize_tls_reloc(is_final, r_type);
+ switch (r_type)
+ {
+ case elfcpp::R_ARM_TLS_GD32: // Global-dynamic
+ {
+ unsigned int got_type = GOT_TYPE_TLS_PAIR;
+ unsigned int got_offset;
+ if (gsym != NULL)
+ {
+ gold_assert(gsym->has_got_offset(got_type));
+ got_offset = gsym->got_offset(got_type) - target->got_size();
+ }
+ else
+ {
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
+ gold_assert(object->local_has_got_offset(r_sym, got_type));
+ got_offset = (object->local_got_offset(r_sym, got_type)
+ - target->got_size());
+ }
+ if (optimized_type == tls::TLSOPT_NONE)
+ {
+ Arm_address got_entry =
+ target->got_plt_section()->address() + got_offset;
+
+ // Relocate the field with the PC relative offset of the pair of
+ // GOT entries.
+ RelocFuncs::pcrel32(view, got_entry, address);
+ return ArmRelocFuncs::STATUS_OKAY;
+ }
+ }
+ break;
- // Every PLT entry needs a reloc.
- gsym->set_needs_dynsym_entry();
- this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
- got_offset);
+ case elfcpp::R_ARM_TLS_LDM32: // Local-dynamic
+ if (optimized_type == tls::TLSOPT_NONE)
+ {
+ // Relocate the field with the offset of the GOT entry for
+ // the module index.
+ unsigned int got_offset;
+ got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
+ - target->got_size());
+ Arm_address got_entry =
+ target->got_plt_section()->address() + got_offset;
+
+ // Relocate the field with the PC relative offset of the pair of
+ // GOT entries.
+ RelocFuncs::pcrel32(view, got_entry, address);
+ return ArmRelocFuncs::STATUS_OKAY;
+ }
+ break;
- // Note that we don't need to save the symbol. The contents of the
- // PLT are independent of which symbols are used. The symbols only
- // appear in the relocations.
-}
+ case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic
+ RelocFuncs::rel32(view, value);
+ return ArmRelocFuncs::STATUS_OKAY;
+
+ case elfcpp::R_ARM_TLS_IE32: // Initial-exec
+ if (optimized_type == tls::TLSOPT_NONE)
+ {
+ // Relocate the field with the offset of the GOT entry for
+ // the tp-relative offset of the symbol.
+ unsigned int got_type = GOT_TYPE_TLS_OFFSET;
+ unsigned int got_offset;
+ if (gsym != NULL)
+ {
+ gold_assert(gsym->has_got_offset(got_type));
+ got_offset = gsym->got_offset(got_type);
+ }
+ else
+ {
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
+ gold_assert(object->local_has_got_offset(r_sym, got_type));
+ got_offset = object->local_got_offset(r_sym, got_type);
+ }
+
+ // All GOT offsets are relative to the end of the GOT.
+ got_offset -= target->got_size();
+
+ Arm_address got_entry =
+ target->got_plt_section()->address() + got_offset;
+
+ // Relocate the field with the PC relative offset of the GOT entry.
+ RelocFuncs::pcrel32(view, got_entry, address);
+ return ArmRelocFuncs::STATUS_OKAY;
+ }
+ break;
-// ARM PLTs.
-// FIXME: This is not very flexible. Right now this has only been tested
-// on armv5te. If we are to support additional architecture features like
-// Thumb-2 or BE8, we need to make this more flexible like GNU ld.
+ case elfcpp::R_ARM_TLS_LE32: // Local-exec
+ // If we're creating a shared library, a dynamic relocation will
+ // have been created for this location, so do not apply it now.
+ if (!parameters->options().shared())
+ {
+ gold_assert(tls_segment != NULL);
-// The first entry in the PLT.
-template<bool big_endian>
-const uint32_t Output_data_plt_arm<big_endian>::first_plt_entry[5] =
-{
- 0xe52de004, // str lr, [sp, #-4]!
- 0xe59fe004, // ldr lr, [pc, #4]
- 0xe08fe00e, // add lr, pc, lr
- 0xe5bef008, // ldr pc, [lr, #8]!
- 0x00000000, // &GOT[0] - .
-};
+ // $tp points to the TCB, which is followed by the TLS, so we
+ // need to add TCB size to the offset.
+ Arm_address aligned_tcb_size =
+ align_address(ARM_TCB_SIZE, tls_segment->maximum_alignment());
+ RelocFuncs::rel32(view, value + aligned_tcb_size);
-// Subsequent entries in the PLT.
+ }
+ return ArmRelocFuncs::STATUS_OKAY;
+
+ default:
+ gold_unreachable();
+ }
-template<bool big_endian>
-const uint32_t Output_data_plt_arm<big_endian>::plt_entry[3] =
-{
- 0xe28fc600, // add ip, pc, #0xNN00000
- 0xe28cca00, // add ip, ip, #0xNN000
- 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
-};
+ gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
+ _("unsupported reloc %u"),
+ r_type);
+ return ArmRelocFuncs::STATUS_BAD_RELOC;
+}
-// Write out the PLT. This uses the hand-coded instructions above,
-// and adjusts them as needed. This is all specified by the arm ELF
-// Processor Supplement.
+// Relocate section data.
template<bool big_endian>
void
-Output_data_plt_arm<big_endian>::do_write(Output_file* of)
+Target_arm<big_endian>::relocate_section(
+ const Relocate_info<32, big_endian>* relinfo,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ unsigned char* view,
+ Arm_address address,
+ section_size_type view_size,
+ const Reloc_symbol_changes* reloc_symbol_changes)
{
- const off_t offset = this->offset();
- const section_size_type oview_size =
- convert_to_section_size_type(this->data_size());
- unsigned char* const oview = of->get_output_view(offset, oview_size);
+ typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
+ gold_assert(sh_type == elfcpp::SHT_REL);
- const off_t got_file_offset = this->got_plt_->offset();
- const section_size_type got_size =
- convert_to_section_size_type(this->got_plt_->data_size());
- unsigned char* const got_view = of->get_output_view(got_file_offset,
- got_size);
- unsigned char* pov = oview;
+ // See if we are relocating a relaxed input section. If so, the view
+ // covers the whole output section and we need to adjust accordingly.
+ if (needs_special_offset_handling)
+ {
+ const Output_relaxed_input_section* poris =
+ output_section->find_relaxed_input_section(relinfo->object,
+ relinfo->data_shndx);
+ if (poris != NULL)
+ {
+ Arm_address section_address = poris->address();
+ section_size_type section_size = poris->data_size();
- elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
- elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
+ gold_assert((section_address >= address)
+ && ((section_address + section_size)
+ <= (address + view_size)));
- // Write first PLT entry. All but the last word are constants.
- const size_t num_first_plt_words = (sizeof(first_plt_entry)
- / sizeof(plt_entry[0]));
- for (size_t i = 0; i < num_first_plt_words - 1; i++)
- elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
- // Last word in first PLT entry is &GOT[0] - .
- elfcpp::Swap<32, big_endian>::writeval(pov + 16,
- got_address - (plt_address + 16));
- pov += sizeof(first_plt_entry);
+ off_t offset = section_address - address;
+ view += offset;
+ address += offset;
+ view_size = section_size;
+ }
+ }
- unsigned char* got_pov = got_view;
+ gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
+ Arm_relocate>(
+ relinfo,
+ this,
+ prelocs,
+ reloc_count,
+ output_section,
+ needs_special_offset_handling,
+ view,
+ address,
+ view_size,
+ reloc_symbol_changes);
+}
- memset(got_pov, 0, 12);
- got_pov += 12;
+// Return the size of a relocation while scanning during a relocatable
+// link.
- const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
- unsigned int plt_offset = sizeof(first_plt_entry);
- unsigned int plt_rel_offset = 0;
- unsigned int got_offset = 12;
- const unsigned int count = this->count_;
- for (unsigned int i = 0;
- i < count;
- ++i,
- pov += sizeof(plt_entry),
- got_pov += 4,
- plt_offset += sizeof(plt_entry),
- plt_rel_offset += rel_size,
- got_offset += 4)
+template<bool big_endian>
+unsigned int
+Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
+ unsigned int r_type,
+ Relobj* object)
+{
+ r_type = get_real_reloc_type(r_type);
+ const Arm_reloc_property* arp =
+ arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
+ if (arp != NULL)
+ return arp->size();
+ else
{
- // Set and adjust the PLT entry itself.
- int32_t offset = ((got_address + got_offset)
- - (plt_address + plt_offset + 8));
+ std::string reloc_name =
+ arm_reloc_property_table->reloc_name_in_error_message(r_type);
+ gold_error(_("%s: unexpected %s in object file"),
+ object->name().c_str(), reloc_name.c_str());
+ return 0;
+ }
+}
- gold_assert(offset >= 0 && offset < 0x0fffffff);
- uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
- elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
- uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
- elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
- uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
- elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
+// Scan the relocs during a relocatable link.
- // Set the entry in the GOT.
- elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
- }
+template<bool big_endian>
+void
+Target_arm<big_endian>::scan_relocatable_relocs(
+ Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<32, big_endian>* object,
+ unsigned int data_shndx,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ size_t local_symbol_count,
+ const unsigned char* plocal_symbols,
+ Relocatable_relocs* rr)
+{
+ gold_assert(sh_type == elfcpp::SHT_REL);
- gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
- gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
+ typedef Arm_scan_relocatable_relocs<big_endian, elfcpp::SHT_REL,
+ Relocatable_size_for_reloc> Scan_relocatable_relocs;
- of->write_output_view(offset, oview_size, oview);
- of->write_output_view(got_file_offset, got_size, got_view);
+ gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
+ Scan_relocatable_relocs>(
+ symtab,
+ layout,
+ object,
+ data_shndx,
+ prelocs,
+ reloc_count,
+ output_section,
+ needs_special_offset_handling,
+ local_symbol_count,
+ plocal_symbols,
+ rr);
}
-// Create a PLT entry for a global symbol.
+// Relocate a section during a relocatable link.
template<bool big_endian>
void
-Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout,
- Symbol* gsym)
+Target_arm<big_endian>::relocate_for_relocatable(
+ const Relocate_info<32, big_endian>* relinfo,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ off_t offset_in_output_section,
+ const Relocatable_relocs* rr,
+ unsigned char* view,
+ Arm_address view_address,
+ section_size_type view_size,
+ unsigned char* reloc_view,
+ section_size_type reloc_view_size)
{
- if (gsym->has_plt_offset())
- return;
-
- if (this->plt_ == NULL)
- {
- // Create the GOT sections first.
- this->got_section(symtab, layout);
+ gold_assert(sh_type == elfcpp::SHT_REL);
- this->plt_ = new Output_data_plt_arm<big_endian>(layout, this->got_plt_);
- layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
- (elfcpp::SHF_ALLOC
- | elfcpp::SHF_EXECINSTR),
- this->plt_);
- }
- this->plt_->add_entry(gsym);
+ gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>(
+ relinfo,
+ prelocs,
+ reloc_count,
+ output_section,
+ offset_in_output_section,
+ rr,
+ view,
+ view_address,
+ view_size,
+ reloc_view,
+ reloc_view_size);
}
-// Report an unsupported relocation against a local symbol.
+// Perform target-specific processing in a relocatable link. This is
+// only used if we use the relocation strategy RELOC_SPECIAL.
template<bool big_endian>
void
-Target_arm<big_endian>::Scan::unsupported_reloc_local(
- Sized_relobj<32, big_endian>* object,
- unsigned int r_type)
+Target_arm<big_endian>::relocate_special_relocatable(
+ const Relocate_info<32, big_endian>* relinfo,
+ unsigned int sh_type,
+ const unsigned char* preloc_in,
+ size_t relnum,
+ Output_section* output_section,
+ off_t offset_in_output_section,
+ unsigned char* view,
+ elfcpp::Elf_types<32>::Elf_Addr view_address,
+ section_size_type,
+ unsigned char* preloc_out)
{
- gold_error(_("%s: unsupported reloc %u against local symbol"),
- object->name().c_str(), r_type);
-}
+ // We can only handle REL type relocation sections.
+ gold_assert(sh_type == elfcpp::SHT_REL);
-// We are about to emit a dynamic relocation of type R_TYPE. If the
-// dynamic linker does not support it, issue an error. The GNU linker
-// only issues a non-PIC error for an allocated read-only section.
-// Here we know the section is allocated, but we don't know that it is
-// read-only. But we check for all the relocation types which the
-// glibc dynamic linker supports, so it seems appropriate to issue an
-// error even if the section is not read-only.
+ typedef typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc Reltype;
+ typedef typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc_write
+ Reltype_write;
+ const Arm_address invalid_address = static_cast<Arm_address>(0) - 1;
+
+ const Arm_relobj<big_endian>* object =
+ Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
+ const unsigned int local_count = object->local_symbol_count();
+
+ Reltype reloc(preloc_in);
+ Reltype_write reloc_write(preloc_out);
+
+ elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
+ const unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
+ const unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
+
+ const Arm_reloc_property* arp =
+ arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
+ gold_assert(arp != NULL);
+
+ // Get the new symbol index.
+ // We only use RELOC_SPECIAL strategy in local relocations.
+ gold_assert(r_sym < local_count);
+
+ // We are adjusting a section symbol. We need to find
+ // the symbol table index of the section symbol for
+ // the output section corresponding to input section
+ // in which this symbol is defined.
+ bool is_ordinary;
+ unsigned int shndx = object->local_symbol_input_shndx(r_sym, &is_ordinary);
+ gold_assert(is_ordinary);
+ Output_section* os = object->output_section(shndx);
+ gold_assert(os != NULL);
+ gold_assert(os->needs_symtab_index());
+ unsigned int new_symndx = os->symtab_index();
+
+ // Get the new offset--the location in the output section where
+ // this relocation should be applied.
+
+ Arm_address offset = reloc.get_r_offset();
+ Arm_address new_offset;
+ if (offset_in_output_section != invalid_address)
+ new_offset = offset + offset_in_output_section;
+ else
+ {
+ section_offset_type sot_offset =
+ convert_types<section_offset_type, Arm_address>(offset);
+ section_offset_type new_sot_offset =
+ output_section->output_offset(object, relinfo->data_shndx,
+ sot_offset);
+ gold_assert(new_sot_offset != -1);
+ new_offset = new_sot_offset;
+ }
-template<bool big_endian>
-void
-Target_arm<big_endian>::Scan::check_non_pic(Relobj* object,
- unsigned int r_type)
-{
- switch (r_type)
+ // In an object file, r_offset is an offset within the section.
+ // In an executable or dynamic object, generated by
+ // --emit-relocs, r_offset is an absolute address.
+ if (!parameters->options().relocatable())
{
- // These are the relocation types supported by glibc for ARM.
- case elfcpp::R_ARM_RELATIVE:
- case elfcpp::R_ARM_COPY:
- case elfcpp::R_ARM_GLOB_DAT:
- case elfcpp::R_ARM_JUMP_SLOT:
- case elfcpp::R_ARM_ABS32:
- case elfcpp::R_ARM_ABS32_NOI:
- case elfcpp::R_ARM_PC24:
- // FIXME: The following 3 types are not supported by Android's dynamic
- // linker.
- case elfcpp::R_ARM_TLS_DTPMOD32:
- case elfcpp::R_ARM_TLS_DTPOFF32:
- case elfcpp::R_ARM_TLS_TPOFF32:
- return;
+ new_offset += view_address;
+ if (offset_in_output_section != invalid_address)
+ new_offset -= offset_in_output_section;
+ }
- default:
- // This prevents us from issuing more than one error per reloc
- // section. But we can still wind up issuing more than one
- // error per object file.
- if (this->issued_non_pic_error_)
- return;
- object->error(_("requires unsupported dynamic reloc; "
- "recompile with -fPIC"));
- this->issued_non_pic_error_ = true;
- return;
+ reloc_write.put_r_offset(new_offset);
+ reloc_write.put_r_info(elfcpp::elf_r_info<32>(new_symndx, r_type));
- case elfcpp::R_ARM_NONE:
- gold_unreachable();
- }
-}
+ // Handle the reloc addend.
+ // The relocation uses a section symbol in the input file.
+ // We are adjusting it to use a section symbol in the output
+ // file. The input section symbol refers to some address in
+ // the input section. We need the relocation in the output
+ // file to refer to that same address. This adjustment to
+ // the addend is the same calculation we use for a simple
+ // absolute relocation for the input section symbol.
-// Scan a relocation for a local symbol.
-// FIXME: This only handles a subset of relocation types used by Android
-// on ARM v5te devices.
+ const Symbol_value<32>* psymval = object->local_symbol(r_sym);
-template<bool big_endian>
-inline void
-Target_arm<big_endian>::Scan::local(const General_options&,
- Symbol_table* symtab,
- Layout* layout,
- Target_arm* target,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- Output_section* output_section,
- const elfcpp::Rel<32, big_endian>& reloc,
- unsigned int r_type,
- const elfcpp::Sym<32, big_endian>&)
-{
- r_type = get_real_reloc_type(r_type);
+ // Handle THUMB bit.
+ Symbol_value<32> symval;
+ Arm_address thumb_bit =
+ object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
+ if (thumb_bit != 0
+ && arp->uses_thumb_bit()
+ && ((psymval->value(object, 0) & 1) != 0))
+ {
+ Arm_address stripped_value =
+ psymval->value(object, 0) & ~static_cast<Arm_address>(1);
+ symval.set_output_value(stripped_value);
+ psymval = &symval;
+ }
+
+ unsigned char* paddend = view + offset;
+ typename Arm_relocate_functions<big_endian>::Status reloc_status =
+ Arm_relocate_functions<big_endian>::STATUS_OKAY;
switch (r_type)
{
- case elfcpp::R_ARM_NONE:
+ case elfcpp::R_ARM_ABS8:
+ reloc_status = Arm_relocate_functions<big_endian>::abs8(paddend, object,
+ psymval);
break;
- case elfcpp::R_ARM_ABS32:
- case elfcpp::R_ARM_ABS32_NOI:
- // If building a shared library (or a position-independent
- // executable), we need to create a dynamic relocation for
- // this location. The relocation applied at link time will
- // apply the link-time value, so we flag the location with
- // an R_ARM_RELATIVE relocation so the dynamic loader can
- // relocate it easily.
- if (parameters->options().output_is_position_independent())
- {
- Reloc_section* rel_dyn = target->rel_dyn_section(layout);
- unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
- // If we are to add more other reloc types than R_ARM_ABS32,
- // we need to add check_non_pic(object, r_type) here.
- rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
- output_section, data_shndx,
- reloc.get_r_offset());
- }
+ case elfcpp::R_ARM_ABS12:
+ reloc_status = Arm_relocate_functions<big_endian>::abs12(paddend, object,
+ psymval);
+ break;
+
+ case elfcpp::R_ARM_ABS16:
+ reloc_status = Arm_relocate_functions<big_endian>::abs16(paddend, object,
+ psymval);
+ break;
+
+ case elfcpp::R_ARM_THM_ABS5:
+ reloc_status = Arm_relocate_functions<big_endian>::thm_abs5(paddend,
+ object,
+ psymval);
+ break;
+
+ case elfcpp::R_ARM_MOVW_ABS_NC:
+ case elfcpp::R_ARM_MOVW_PREL_NC:
+ case elfcpp::R_ARM_MOVW_BREL_NC:
+ case elfcpp::R_ARM_MOVW_BREL:
+ reloc_status = Arm_relocate_functions<big_endian>::movw(
+ paddend, object, psymval, 0, thumb_bit, arp->checks_overflow());
+ break;
+
+ case elfcpp::R_ARM_THM_MOVW_ABS_NC:
+ case elfcpp::R_ARM_THM_MOVW_PREL_NC:
+ case elfcpp::R_ARM_THM_MOVW_BREL_NC:
+ case elfcpp::R_ARM_THM_MOVW_BREL:
+ reloc_status = Arm_relocate_functions<big_endian>::thm_movw(
+ paddend, object, psymval, 0, thumb_bit, arp->checks_overflow());
break;
- case elfcpp::R_ARM_REL32:
case elfcpp::R_ARM_THM_CALL:
+ case elfcpp::R_ARM_THM_XPC22:
+ case elfcpp::R_ARM_THM_JUMP24:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::thumb_branch_common(
+ r_type, relinfo, paddend, NULL, object, 0, psymval, 0, thumb_bit,
+ false);
+ break;
+
+ case elfcpp::R_ARM_PLT32:
case elfcpp::R_ARM_CALL:
- case elfcpp::R_ARM_PREL31:
case elfcpp::R_ARM_JUMP24:
- case elfcpp::R_ARM_PLT32:
- case elfcpp::R_ARM_THM_ABS5:
- case elfcpp::R_ARM_ABS8:
- case elfcpp::R_ARM_ABS12:
- case elfcpp::R_ARM_ABS16:
- case elfcpp::R_ARM_BASE_ABS:
- case elfcpp::R_ARM_MOVW_ABS_NC:
+ case elfcpp::R_ARM_XPC25:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::arm_branch_common(
+ r_type, relinfo, paddend, NULL, object, 0, psymval, 0, thumb_bit,
+ false);
+ break;
+
+ case elfcpp::R_ARM_THM_JUMP19:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::thm_jump19(paddend, object,
+ psymval, 0, thumb_bit);
+ break;
+
+ case elfcpp::R_ARM_THM_JUMP6:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::thm_jump6(paddend, object, psymval,
+ 0);
+ break;
+
+ case elfcpp::R_ARM_THM_JUMP8:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::thm_jump8(paddend, object, psymval,
+ 0);
+ break;
+
+ case elfcpp::R_ARM_THM_JUMP11:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::thm_jump11(paddend, object, psymval,
+ 0);
+ break;
+
+ case elfcpp::R_ARM_PREL31:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::prel31(paddend, object, psymval, 0,
+ thumb_bit);
+ break;
+
+ case elfcpp::R_ARM_THM_PC8:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::thm_pc8(paddend, object, psymval,
+ 0);
+ break;
+
+ case elfcpp::R_ARM_THM_PC12:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::thm_pc12(paddend, object, psymval,
+ 0);
+ break;
+
+ case elfcpp::R_ARM_THM_ALU_PREL_11_0:
+ reloc_status =
+ Arm_relocate_functions<big_endian>::thm_alu11(paddend, object, psymval,
+ 0, thumb_bit);
+ break;
+
+ // These relocation truncate relocation results so we cannot handle them
+ // in a relocatable link.
case elfcpp::R_ARM_MOVT_ABS:
- case elfcpp::R_ARM_THM_MOVW_ABS_NC:
case elfcpp::R_ARM_THM_MOVT_ABS:
- case elfcpp::R_ARM_MOVW_PREL_NC:
case elfcpp::R_ARM_MOVT_PREL:
- case elfcpp::R_ARM_THM_MOVW_PREL_NC:
+ case elfcpp::R_ARM_MOVT_BREL:
case elfcpp::R_ARM_THM_MOVT_PREL:
+ case elfcpp::R_ARM_THM_MOVT_BREL:
+ case elfcpp::R_ARM_ALU_PC_G0_NC:
+ case elfcpp::R_ARM_ALU_PC_G0:
+ case elfcpp::R_ARM_ALU_PC_G1_NC:
+ case elfcpp::R_ARM_ALU_PC_G1:
+ case elfcpp::R_ARM_ALU_PC_G2:
+ case elfcpp::R_ARM_ALU_SB_G0_NC:
+ case elfcpp::R_ARM_ALU_SB_G0:
+ case elfcpp::R_ARM_ALU_SB_G1_NC:
+ case elfcpp::R_ARM_ALU_SB_G1:
+ case elfcpp::R_ARM_ALU_SB_G2:
+ case elfcpp::R_ARM_LDR_PC_G0:
+ case elfcpp::R_ARM_LDR_PC_G1:
+ case elfcpp::R_ARM_LDR_PC_G2:
+ case elfcpp::R_ARM_LDR_SB_G0:
+ case elfcpp::R_ARM_LDR_SB_G1:
+ case elfcpp::R_ARM_LDR_SB_G2:
+ case elfcpp::R_ARM_LDRS_PC_G0:
+ case elfcpp::R_ARM_LDRS_PC_G1:
+ case elfcpp::R_ARM_LDRS_PC_G2:
+ case elfcpp::R_ARM_LDRS_SB_G0:
+ case elfcpp::R_ARM_LDRS_SB_G1:
+ case elfcpp::R_ARM_LDRS_SB_G2:
+ case elfcpp::R_ARM_LDC_PC_G0:
+ case elfcpp::R_ARM_LDC_PC_G1:
+ case elfcpp::R_ARM_LDC_PC_G2:
+ case elfcpp::R_ARM_LDC_SB_G0:
+ case elfcpp::R_ARM_LDC_SB_G1:
+ case elfcpp::R_ARM_LDC_SB_G2:
+ gold_error(_("cannot handle %s in a relocatable link"),
+ arp->name().c_str());
break;
- case elfcpp::R_ARM_GOTOFF32:
- // We need a GOT section:
- target->got_section(symtab, layout);
- break;
+ default:
+ gold_unreachable();
+ }
- case elfcpp::R_ARM_BASE_PREL:
- // FIXME: What about this?
+ // Report any errors.
+ switch (reloc_status)
+ {
+ case Arm_relocate_functions<big_endian>::STATUS_OKAY:
break;
-
- case elfcpp::R_ARM_GOT_BREL:
- case elfcpp::R_ARM_GOT_PREL:
- {
- // The symbol requires a GOT entry.
- Output_data_got<32, big_endian>* got =
- target->got_section(symtab, layout);
- unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
- if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
- {
- // If we are generating a shared object, we need to add a
- // dynamic RELATIVE relocation for this symbol's GOT entry.
- if (parameters->options().output_is_position_independent())
- {
- Reloc_section* rel_dyn = target->rel_dyn_section(layout);
- unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
- rel_dyn->add_local_relative(
- object, r_sym, elfcpp::R_ARM_RELATIVE, got,
- object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
- }
- }
- }
+ case Arm_relocate_functions<big_endian>::STATUS_OVERFLOW:
+ gold_error_at_location(relinfo, relnum, reloc.get_r_offset(),
+ _("relocation overflow in %s"),
+ arp->name().c_str());
break;
+ case Arm_relocate_functions<big_endian>::STATUS_BAD_RELOC:
+ gold_error_at_location(relinfo, relnum, reloc.get_r_offset(),
+ _("unexpected opcode while processing relocation %s"),
+ arp->name().c_str());
+ break;
+ default:
+ gold_unreachable();
+ }
+}
+
+// Return the value to use for a dynamic symbol which requires special
+// treatment. This is how we support equality comparisons of function
+// pointers across shared library boundaries, as described in the
+// processor specific ABI supplement.
+
+template<bool big_endian>
+uint64_t
+Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
+{
+ gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
+ return this->plt_section()->address() + gsym->plt_offset();
+}
+// Map platform-specific relocs to real relocs
+//
+template<bool big_endian>
+unsigned int
+Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type)
+{
+ switch (r_type)
+ {
case elfcpp::R_ARM_TARGET1:
- // This should have been mapped to another type already.
- // Fall through.
- case elfcpp::R_ARM_COPY:
- case elfcpp::R_ARM_GLOB_DAT:
- case elfcpp::R_ARM_JUMP_SLOT:
- case elfcpp::R_ARM_RELATIVE:
- // These are relocations which should only be seen by the
- // dynamic linker, and should never be seen here.
- gold_error(_("%s: unexpected reloc %u in object file"),
- object->name().c_str(), r_type);
- break;
+ // This is either R_ARM_ABS32 or R_ARM_REL32;
+ return elfcpp::R_ARM_ABS32;
+
+ case elfcpp::R_ARM_TARGET2:
+ // This can be any reloc type but ususally is R_ARM_GOT_PREL
+ return elfcpp::R_ARM_GOT_PREL;
default:
- unsupported_reloc_local(object, r_type);
- break;
+ return r_type;
}
}
-// Report an unsupported relocation against a global symbol.
+// Whether if two EABI versions V1 and V2 are compatible.
+
+template<bool big_endian>
+bool
+Target_arm<big_endian>::are_eabi_versions_compatible(
+ elfcpp::Elf_Word v1,
+ elfcpp::Elf_Word v2)
+{
+ // v4 and v5 are the same spec before and after it was released,
+ // so allow mixing them.
+ if ((v1 == elfcpp::EF_ARM_EABI_UNKNOWN || v2 == elfcpp::EF_ARM_EABI_UNKNOWN)
+ || (v1 == elfcpp::EF_ARM_EABI_VER4 && v2 == elfcpp::EF_ARM_EABI_VER5)
+ || (v1 == elfcpp::EF_ARM_EABI_VER5 && v2 == elfcpp::EF_ARM_EABI_VER4))
+ return true;
+
+ return v1 == v2;
+}
+
+// Combine FLAGS from an input object called NAME and the processor-specific
+// flags in the ELF header of the output. Much of this is adapted from the
+// processor-specific flags merging code in elf32_arm_merge_private_bfd_data
+// in bfd/elf32-arm.c.
template<bool big_endian>
void
-Target_arm<big_endian>::Scan::unsupported_reloc_global(
- Sized_relobj<32, big_endian>* object,
- unsigned int r_type,
- Symbol* gsym)
+Target_arm<big_endian>::merge_processor_specific_flags(
+ const std::string& name,
+ elfcpp::Elf_Word flags)
{
- gold_error(_("%s: unsupported reloc %u against global symbol %s"),
- object->name().c_str(), r_type, gsym->demangled_name().c_str());
+ if (this->are_processor_specific_flags_set())
+ {
+ elfcpp::Elf_Word out_flags = this->processor_specific_flags();
+
+ // Nothing to merge if flags equal to those in output.
+ if (flags == out_flags)
+ return;
+
+ // Complain about various flag mismatches.
+ elfcpp::Elf_Word version1 = elfcpp::arm_eabi_version(flags);
+ elfcpp::Elf_Word version2 = elfcpp::arm_eabi_version(out_flags);
+ if (!this->are_eabi_versions_compatible(version1, version2)
+ && parameters->options().warn_mismatch())
+ gold_error(_("Source object %s has EABI version %d but output has "
+ "EABI version %d."),
+ name.c_str(),
+ (flags & elfcpp::EF_ARM_EABIMASK) >> 24,
+ (out_flags & elfcpp::EF_ARM_EABIMASK) >> 24);
+ }
+ else
+ {
+ // If the input is the default architecture and had the default
+ // flags then do not bother setting the flags for the output
+ // architecture, instead allow future merges to do this. If no
+ // future merges ever set these flags then they will retain their
+ // uninitialised values, which surprise surprise, correspond
+ // to the default values.
+ if (flags == 0)
+ return;
+
+ // This is the first time, just copy the flags.
+ // We only copy the EABI version for now.
+ this->set_processor_specific_flags(flags & elfcpp::EF_ARM_EABIMASK);
+ }
}
-// Scan a relocation for a global symbol.
-// FIXME: This only handles a subset of relocation types used by Android
-// on ARM v5te devices.
+// Adjust ELF file header.
+template<bool big_endian>
+void
+Target_arm<big_endian>::do_adjust_elf_header(
+ unsigned char* view,
+ int len) const
+{
+ gold_assert(len == elfcpp::Elf_sizes<32>::ehdr_size);
+
+ elfcpp::Ehdr<32, big_endian> ehdr(view);
+ unsigned char e_ident[elfcpp::EI_NIDENT];
+ memcpy(e_ident, ehdr.get_e_ident(), elfcpp::EI_NIDENT);
+
+ if (elfcpp::arm_eabi_version(this->processor_specific_flags())
+ == elfcpp::EF_ARM_EABI_UNKNOWN)
+ e_ident[elfcpp::EI_OSABI] = elfcpp::ELFOSABI_ARM;
+ else
+ e_ident[elfcpp::EI_OSABI] = 0;
+ e_ident[elfcpp::EI_ABIVERSION] = 0;
+
+ // FIXME: Do EF_ARM_BE8 adjustment.
+
+ elfcpp::Ehdr_write<32, big_endian> oehdr(view);
+ oehdr.put_e_ident(e_ident);
+}
+
+// do_make_elf_object to override the same function in the base class.
+// We need to use a target-specific sub-class of Sized_relobj<32, big_endian>
+// to store ARM specific information. Hence we need to have our own
+// ELF object creation.
template<bool big_endian>
-inline void
-Target_arm<big_endian>::Scan::global(const General_options&,
- Symbol_table* symtab,
- Layout* layout,
- Target_arm* target,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- Output_section* output_section,
- const elfcpp::Rel<32, big_endian>& reloc,
- unsigned int r_type,
- Symbol* gsym)
+Object*
+Target_arm<big_endian>::do_make_elf_object(
+ const std::string& name,
+ Input_file* input_file,
+ off_t offset, const elfcpp::Ehdr<32, big_endian>& ehdr)
{
- r_type = get_real_reloc_type(r_type);
- switch (r_type)
+ int et = ehdr.get_e_type();
+ if (et == elfcpp::ET_REL)
{
- case elfcpp::R_ARM_NONE:
- break;
+ Arm_relobj<big_endian>* obj =
+ new Arm_relobj<big_endian>(name, input_file, offset, ehdr);
+ obj->setup();
+ return obj;
+ }
+ else if (et == elfcpp::ET_DYN)
+ {
+ Sized_dynobj<32, big_endian>* obj =
+ new Arm_dynobj<big_endian>(name, input_file, offset, ehdr);
+ obj->setup();
+ return obj;
+ }
+ else
+ {
+ gold_error(_("%s: unsupported ELF file type %d"),
+ name.c_str(), et);
+ return NULL;
+ }
+}
- case elfcpp::R_ARM_ABS32:
- case elfcpp::R_ARM_ABS32_NOI:
- {
- // Make a dynamic relocation if necessary.
- if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
- {
- if (target->may_need_copy_reloc(gsym))
- {
- target->copy_reloc(symtab, layout, object,
- data_shndx, output_section, gsym, reloc);
- }
- else if (gsym->can_use_relative_reloc(false))
- {
- // If we are to add more other reloc types than R_ARM_ABS32,
- // we need to add check_non_pic(object, r_type) here.
- Reloc_section* rel_dyn = target->rel_dyn_section(layout);
- rel_dyn->add_global_relative(gsym, elfcpp::R_ARM_RELATIVE,
- output_section, object,
- data_shndx, reloc.get_r_offset());
- }
- else
- {
- // If we are to add more other reloc types than R_ARM_ABS32,
- // we need to add check_non_pic(object, r_type) here.
- Reloc_section* rel_dyn = target->rel_dyn_section(layout);
- rel_dyn->add_global(gsym, r_type, output_section, object,
- data_shndx, reloc.get_r_offset());
- }
- }
- }
- break;
+// Read the architecture from the Tag_also_compatible_with attribute, if any.
+// Returns -1 if no architecture could be read.
+// This is adapted from get_secondary_compatible_arch() in bfd/elf32-arm.c.
- case elfcpp::R_ARM_MOVW_ABS_NC:
- case elfcpp::R_ARM_MOVT_ABS:
- case elfcpp::R_ARM_THM_MOVW_ABS_NC:
- case elfcpp::R_ARM_THM_MOVT_ABS:
- case elfcpp::R_ARM_MOVW_PREL_NC:
- case elfcpp::R_ARM_MOVT_PREL:
- case elfcpp::R_ARM_THM_MOVW_PREL_NC:
- case elfcpp::R_ARM_THM_MOVT_PREL:
- break;
+template<bool big_endian>
+int
+Target_arm<big_endian>::get_secondary_compatible_arch(
+ const Attributes_section_data* pasd)
+{
+ const Object_attribute *known_attributes =
+ pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
+
+ // Note: the tag and its argument below are uleb128 values, though
+ // currently-defined values fit in one byte for each.
+ const std::string& sv =
+ known_attributes[elfcpp::Tag_also_compatible_with].string_value();
+ if (sv.size() == 2
+ && sv.data()[0] == elfcpp::Tag_CPU_arch
+ && (sv.data()[1] & 128) != 128)
+ return sv.data()[1];
+
+ // This tag is "safely ignorable", so don't complain if it looks funny.
+ return -1;
+}
- case elfcpp::R_ARM_THM_ABS5:
- case elfcpp::R_ARM_ABS8:
- case elfcpp::R_ARM_ABS12:
- case elfcpp::R_ARM_ABS16:
- case elfcpp::R_ARM_BASE_ABS:
- {
- // No dynamic relocs of this kinds.
- // Report the error in case of PIC.
- int flags = Symbol::NON_PIC_REF;
- if (gsym->type() == elfcpp::STT_FUNC
- || gsym->type() == elfcpp::STT_ARM_TFUNC)
- flags |= Symbol::FUNCTION_CALL;
- if (gsym->needs_dynamic_reloc(flags))
- check_non_pic(object, r_type);
- }
- break;
+// Set, or unset, the architecture of the Tag_also_compatible_with attribute.
+// The tag is removed if ARCH is -1.
+// This is adapted from set_secondary_compatible_arch() in bfd/elf32-arm.c.
- case elfcpp::R_ARM_REL32:
- case elfcpp::R_ARM_PREL31:
- {
- // Make a dynamic relocation if necessary.
- int flags = Symbol::NON_PIC_REF;
- if (gsym->needs_dynamic_reloc(flags))
- {
- if (target->may_need_copy_reloc(gsym))
- {
- target->copy_reloc(symtab, layout, object,
- data_shndx, output_section, gsym, reloc);
- }
- else
- {
- check_non_pic(object, r_type);
- Reloc_section* rel_dyn = target->rel_dyn_section(layout);
- rel_dyn->add_global(gsym, r_type, output_section, object,
- data_shndx, reloc.get_r_offset());
- }
- }
- }
- break;
+template<bool big_endian>
+void
+Target_arm<big_endian>::set_secondary_compatible_arch(
+ Attributes_section_data* pasd,
+ int arch)
+{
+ Object_attribute *known_attributes =
+ pasd->known_attributes(Object_attribute::OBJ_ATTR_PROC);
- case elfcpp::R_ARM_JUMP24:
- case elfcpp::R_ARM_THM_CALL:
- case elfcpp::R_ARM_CALL:
- {
- if (Target_arm<big_endian>::Scan::symbol_needs_plt_entry(gsym))
- target->make_plt_entry(symtab, layout, gsym);
- // Make a dynamic relocation if necessary.
- int flags = Symbol::NON_PIC_REF;
- if (gsym->type() == elfcpp::STT_FUNC
- || gsym->type() == elfcpp::STT_ARM_TFUNC)
- flags |= Symbol::FUNCTION_CALL;
- if (gsym->needs_dynamic_reloc(flags))
- {
- if (target->may_need_copy_reloc(gsym))
- {
- target->copy_reloc(symtab, layout, object,
- data_shndx, output_section, gsym,
- reloc);
- }
- else
- {
- check_non_pic(object, r_type);
- Reloc_section* rel_dyn = target->rel_dyn_section(layout);
- rel_dyn->add_global(gsym, r_type, output_section, object,
- data_shndx, reloc.get_r_offset());
- }
- }
- }
- break;
+ if (arch == -1)
+ {
+ known_attributes[elfcpp::Tag_also_compatible_with].set_string_value("");
+ return;
+ }
- case elfcpp::R_ARM_PLT32:
- // If the symbol is fully resolved, this is just a relative
- // local reloc. Otherwise we need a PLT entry.
- if (gsym->final_value_is_known())
- break;
- // If building a shared library, we can also skip the PLT entry
- // if the symbol is defined in the output file and is protected
- // or hidden.
- if (gsym->is_defined()
- && !gsym->is_from_dynobj()
- && !gsym->is_preemptible())
- break;
- target->make_plt_entry(symtab, layout, gsym);
- break;
+ // Note: the tag and its argument below are uleb128 values, though
+ // currently-defined values fit in one byte for each.
+ char sv[3];
+ sv[0] = elfcpp::Tag_CPU_arch;
+ gold_assert(arch != 0);
+ sv[1] = arch;
+ sv[2] = '\0';
- case elfcpp::R_ARM_GOTOFF32:
- // We need a GOT section.
- target->got_section(symtab, layout);
- break;
+ known_attributes[elfcpp::Tag_also_compatible_with].set_string_value(sv);
+}
- case elfcpp::R_ARM_BASE_PREL:
- // FIXME: What about this?
- break;
-
- case elfcpp::R_ARM_GOT_BREL:
- case elfcpp::R_ARM_GOT_PREL:
- {
- // The symbol requires a GOT entry.
- Output_data_got<32, big_endian>* got =
- target->got_section(symtab, layout);
- if (gsym->final_value_is_known())
- got->add_global(gsym, GOT_TYPE_STANDARD);
- else
- {
- // If this symbol is not fully resolved, we need to add a
- // GOT entry with a dynamic relocation.
- Reloc_section* rel_dyn = target->rel_dyn_section(layout);
- if (gsym->is_from_dynobj()
- || gsym->is_undefined()
- || gsym->is_preemptible())
- got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
- rel_dyn, elfcpp::R_ARM_GLOB_DAT);
- else
- {
- if (got->add_global(gsym, GOT_TYPE_STANDARD))
- rel_dyn->add_global_relative(
- gsym, elfcpp::R_ARM_RELATIVE, got,
- gsym->got_offset(GOT_TYPE_STANDARD));
- }
- }
- }
- break;
+// Combine two values for Tag_CPU_arch, taking secondary compatibility tags
+// into account.
+// This is adapted from tag_cpu_arch_combine() in bfd/elf32-arm.c.
- case elfcpp::R_ARM_TARGET1:
- // This should have been mapped to another type already.
- // Fall through.
- case elfcpp::R_ARM_COPY:
- case elfcpp::R_ARM_GLOB_DAT:
- case elfcpp::R_ARM_JUMP_SLOT:
- case elfcpp::R_ARM_RELATIVE:
- // These are relocations which should only be seen by the
- // dynamic linker, and should never be seen here.
- gold_error(_("%s: unexpected reloc %u in object file"),
- object->name().c_str(), r_type);
- break;
+template<bool big_endian>
+int
+Target_arm<big_endian>::tag_cpu_arch_combine(
+ const char* name,
+ int oldtag,
+ int* secondary_compat_out,
+ int newtag,
+ int secondary_compat)
+{
+#define T(X) elfcpp::TAG_CPU_ARCH_##X
+ static const int v6t2[] =
+ {
+ T(V6T2), // PRE_V4.
+ T(V6T2), // V4.
+ T(V6T2), // V4T.
+ T(V6T2), // V5T.
+ T(V6T2), // V5TE.
+ T(V6T2), // V5TEJ.
+ T(V6T2), // V6.
+ T(V7), // V6KZ.
+ T(V6T2) // V6T2.
+ };
+ static const int v6k[] =
+ {
+ T(V6K), // PRE_V4.
+ T(V6K), // V4.
+ T(V6K), // V4T.
+ T(V6K), // V5T.
+ T(V6K), // V5TE.
+ T(V6K), // V5TEJ.
+ T(V6K), // V6.
+ T(V6KZ), // V6KZ.
+ T(V7), // V6T2.
+ T(V6K) // V6K.
+ };
+ static const int v7[] =
+ {
+ T(V7), // PRE_V4.
+ T(V7), // V4.
+ T(V7), // V4T.
+ T(V7), // V5T.
+ T(V7), // V5TE.
+ T(V7), // V5TEJ.
+ T(V7), // V6.
+ T(V7), // V6KZ.
+ T(V7), // V6T2.
+ T(V7), // V6K.
+ T(V7) // V7.
+ };
+ static const int v6_m[] =
+ {
+ -1, // PRE_V4.
+ -1, // V4.
+ T(V6K), // V4T.
+ T(V6K), // V5T.
+ T(V6K), // V5TE.
+ T(V6K), // V5TEJ.
+ T(V6K), // V6.
+ T(V6KZ), // V6KZ.
+ T(V7), // V6T2.
+ T(V6K), // V6K.
+ T(V7), // V7.
+ T(V6_M) // V6_M.
+ };
+ static const int v6s_m[] =
+ {
+ -1, // PRE_V4.
+ -1, // V4.
+ T(V6K), // V4T.
+ T(V6K), // V5T.
+ T(V6K), // V5TE.
+ T(V6K), // V5TEJ.
+ T(V6K), // V6.
+ T(V6KZ), // V6KZ.
+ T(V7), // V6T2.
+ T(V6K), // V6K.
+ T(V7), // V7.
+ T(V6S_M), // V6_M.
+ T(V6S_M) // V6S_M.
+ };
+ static const int v7e_m[] =
+ {
+ -1, // PRE_V4.
+ -1, // V4.
+ T(V7E_M), // V4T.
+ T(V7E_M), // V5T.
+ T(V7E_M), // V5TE.
+ T(V7E_M), // V5TEJ.
+ T(V7E_M), // V6.
+ T(V7E_M), // V6KZ.
+ T(V7E_M), // V6T2.
+ T(V7E_M), // V6K.
+ T(V7E_M), // V7.
+ T(V7E_M), // V6_M.
+ T(V7E_M), // V6S_M.
+ T(V7E_M) // V7E_M.
+ };
+ static const int v4t_plus_v6_m[] =
+ {
+ -1, // PRE_V4.
+ -1, // V4.
+ T(V4T), // V4T.
+ T(V5T), // V5T.
+ T(V5TE), // V5TE.
+ T(V5TEJ), // V5TEJ.
+ T(V6), // V6.
+ T(V6KZ), // V6KZ.
+ T(V6T2), // V6T2.
+ T(V6K), // V6K.
+ T(V7), // V7.
+ T(V6_M), // V6_M.
+ T(V6S_M), // V6S_M.
+ T(V7E_M), // V7E_M.
+ T(V4T_PLUS_V6_M) // V4T plus V6_M.
+ };
+ static const int *comb[] =
+ {
+ v6t2,
+ v6k,
+ v7,
+ v6_m,
+ v6s_m,
+ v7e_m,
+ // Pseudo-architecture.
+ v4t_plus_v6_m
+ };
- default:
- unsupported_reloc_global(object, r_type, gsym);
- break;
+ // Check we've not got a higher architecture than we know about.
+
+ if (oldtag >= elfcpp::MAX_TAG_CPU_ARCH || newtag >= elfcpp::MAX_TAG_CPU_ARCH)
+ {
+ gold_error(_("%s: unknown CPU architecture"), name);
+ return -1;
+ }
+
+ // Override old tag if we have a Tag_also_compatible_with on the output.
+
+ if ((oldtag == T(V6_M) && *secondary_compat_out == T(V4T))
+ || (oldtag == T(V4T) && *secondary_compat_out == T(V6_M)))
+ oldtag = T(V4T_PLUS_V6_M);
+
+ // And override the new tag if we have a Tag_also_compatible_with on the
+ // input.
+
+ if ((newtag == T(V6_M) && secondary_compat == T(V4T))
+ || (newtag == T(V4T) && secondary_compat == T(V6_M)))
+ newtag = T(V4T_PLUS_V6_M);
+
+ // Architectures before V6KZ add features monotonically.
+ int tagh = std::max(oldtag, newtag);
+ if (tagh <= elfcpp::TAG_CPU_ARCH_V6KZ)
+ return tagh;
+
+ int tagl = std::min(oldtag, newtag);
+ int result = comb[tagh - T(V6T2)][tagl];
+
+ // Use Tag_CPU_arch == V4T and Tag_also_compatible_with (Tag_CPU_arch V6_M)
+ // as the canonical version.
+ if (result == T(V4T_PLUS_V6_M))
+ {
+ result = T(V4T);
+ *secondary_compat_out = T(V6_M);
+ }
+ else
+ *secondary_compat_out = -1;
+
+ if (result == -1)
+ {
+ gold_error(_("%s: conflicting CPU architectures %d/%d"),
+ name, oldtag, newtag);
+ return -1;
}
+
+ return result;
+#undef T
}
-// Process relocations for gc.
+// Helper to print AEABI enum tag value.
template<bool big_endian>
-void
-Target_arm<big_endian>::gc_process_relocs(const General_options& options,
- Symbol_table* symtab,
- Layout* layout,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- unsigned int,
- const unsigned char* prelocs,
- size_t reloc_count,
- Output_section* output_section,
- bool needs_special_offset_handling,
- size_t local_symbol_count,
- const unsigned char* plocal_symbols)
+std::string
+Target_arm<big_endian>::aeabi_enum_name(unsigned int value)
{
- typedef Target_arm<big_endian> Arm;
- typedef typename Target_arm<big_endian>::Scan Scan;
+ static const char *aeabi_enum_names[] =
+ { "", "variable-size", "32-bit", "" };
+ const size_t aeabi_enum_names_size =
+ sizeof(aeabi_enum_names) / sizeof(aeabi_enum_names[0]);
- gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan>(
- options,
- symtab,
- layout,
- this,
- object,
- data_shndx,
- prelocs,
- reloc_count,
- output_section,
- needs_special_offset_handling,
- local_symbol_count,
- plocal_symbols);
+ if (value < aeabi_enum_names_size)
+ return std::string(aeabi_enum_names[value]);
+ else
+ {
+ char buffer[100];
+ sprintf(buffer, "<unknown value %u>", value);
+ return std::string(buffer);
+ }
}
-// Scan relocations for a section.
+// Return the string value to store in TAG_CPU_name.
template<bool big_endian>
-void
-Target_arm<big_endian>::scan_relocs(const General_options& options,
- Symbol_table* symtab,
- Layout* layout,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- unsigned int sh_type,
- const unsigned char* prelocs,
- size_t reloc_count,
- Output_section* output_section,
- bool needs_special_offset_handling,
- size_t local_symbol_count,
- const unsigned char* plocal_symbols)
+std::string
+Target_arm<big_endian>::tag_cpu_name_value(unsigned int value)
{
- typedef typename Target_arm<big_endian>::Scan Scan;
- if (sh_type == elfcpp::SHT_RELA)
+ static const char *name_table[] = {
+ // These aren't real CPU names, but we can't guess
+ // that from the architecture version alone.
+ "Pre v4",
+ "ARM v4",
+ "ARM v4T",
+ "ARM v5T",
+ "ARM v5TE",
+ "ARM v5TEJ",
+ "ARM v6",
+ "ARM v6KZ",
+ "ARM v6T2",
+ "ARM v6K",
+ "ARM v7",
+ "ARM v6-M",
+ "ARM v6S-M",
+ "ARM v7E-M"
+ };
+ const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]);
+
+ if (value < name_table_size)
+ return std::string(name_table[value]);
+ else
{
- gold_error(_("%s: unsupported RELA reloc section"),
- object->name().c_str());
- return;
- }
-
- gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
- options,
- symtab,
- layout,
- this,
- object,
- data_shndx,
- prelocs,
- reloc_count,
- output_section,
- needs_special_offset_handling,
- local_symbol_count,
- plocal_symbols);
+ char buffer[100];
+ sprintf(buffer, "<unknown CPU value %u>", value);
+ return std::string(buffer);
+ }
}
-// Finalize the sections.
+// Merge object attributes from input file called NAME with those of the
+// output. The input object attributes are in the object pointed by PASD.
template<bool big_endian>
void
-Target_arm<big_endian>::do_finalize_sections(Layout* layout)
+Target_arm<big_endian>::merge_object_attributes(
+ const char* name,
+ const Attributes_section_data* pasd)
{
- // Fill in some more dynamic tags.
- Output_data_dynamic* const odyn = layout->dynamic_data();
- if (odyn != NULL)
+ // Return if there is no attributes section data.
+ if (pasd == NULL)
+ return;
+
+ // If output has no object attributes, just copy.
+ const int vendor = Object_attribute::OBJ_ATTR_PROC;
+ if (this->attributes_section_data_ == NULL)
{
- if (this->got_plt_ != NULL)
- odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
+ this->attributes_section_data_ = new Attributes_section_data(*pasd);
+ Object_attribute* out_attr =
+ this->attributes_section_data_->known_attributes(vendor);
- if (this->plt_ != NULL)
+ // We do not output objects with Tag_MPextension_use_legacy - we move
+ // the attribute's value to Tag_MPextension_use. */
+ if (out_attr[elfcpp::Tag_MPextension_use_legacy].int_value() != 0)
{
- const Output_data* od = this->plt_->rel_plt();
- odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
- odyn->add_section_address(elfcpp::DT_JMPREL, od);
- odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL);
- }
+ if (out_attr[elfcpp::Tag_MPextension_use].int_value() != 0
+ && out_attr[elfcpp::Tag_MPextension_use_legacy].int_value()
+ != out_attr[elfcpp::Tag_MPextension_use].int_value())
+ {
+ gold_error(_("%s has both the current and legacy "
+ "Tag_MPextension_use attributes"),
+ name);
+ }
- if (this->rel_dyn_ != NULL)
- {
- const Output_data* od = this->rel_dyn_;
- odyn->add_section_address(elfcpp::DT_REL, od);
- odyn->add_section_size(elfcpp::DT_RELSZ, od);
- odyn->add_constant(elfcpp::DT_RELENT,
- elfcpp::Elf_sizes<32>::rel_size);
+ out_attr[elfcpp::Tag_MPextension_use] =
+ out_attr[elfcpp::Tag_MPextension_use_legacy];
+ out_attr[elfcpp::Tag_MPextension_use_legacy].set_type(0);
+ out_attr[elfcpp::Tag_MPextension_use_legacy].set_int_value(0);
}
- if (!parameters->options().shared())
+ return;
+ }
+
+ const Object_attribute* in_attr = pasd->known_attributes(vendor);
+ Object_attribute* out_attr =
+ this->attributes_section_data_->known_attributes(vendor);
+
+ // This needs to happen before Tag_ABI_FP_number_model is merged. */
+ if (in_attr[elfcpp::Tag_ABI_VFP_args].int_value()
+ != out_attr[elfcpp::Tag_ABI_VFP_args].int_value())
+ {
+ // Ignore mismatches if the object doesn't use floating point. */
+ if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0)
+ out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value(
+ in_attr[elfcpp::Tag_ABI_VFP_args].int_value());
+ else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0
+ && parameters->options().warn_mismatch())
+ gold_error(_("%s uses VFP register arguments, output does not"),
+ name);
+ }
+
+ for (int i = 4; i < Vendor_object_attributes::NUM_KNOWN_ATTRIBUTES; ++i)
+ {
+ // Merge this attribute with existing attributes.
+ switch (i)
{
- // The value of the DT_DEBUG tag is filled in by the dynamic
- // linker at run time, and used by the debugger.
- odyn->add_constant(elfcpp::DT_DEBUG, 0);
+ case elfcpp::Tag_CPU_raw_name:
+ case elfcpp::Tag_CPU_name:
+ // These are merged after Tag_CPU_arch.
+ break;
+
+ case elfcpp::Tag_ABI_optimization_goals:
+ case elfcpp::Tag_ABI_FP_optimization_goals:
+ // Use the first value seen.
+ break;
+
+ case elfcpp::Tag_CPU_arch:
+ {
+ unsigned int saved_out_attr = out_attr->int_value();
+ // Merge Tag_CPU_arch and Tag_also_compatible_with.
+ int secondary_compat =
+ this->get_secondary_compatible_arch(pasd);
+ int secondary_compat_out =
+ this->get_secondary_compatible_arch(
+ this->attributes_section_data_);
+ out_attr[i].set_int_value(
+ tag_cpu_arch_combine(name, out_attr[i].int_value(),
+ &secondary_compat_out,
+ in_attr[i].int_value(),
+ secondary_compat));
+ this->set_secondary_compatible_arch(this->attributes_section_data_,
+ secondary_compat_out);
+
+ // Merge Tag_CPU_name and Tag_CPU_raw_name.
+ if (out_attr[i].int_value() == saved_out_attr)
+ ; // Leave the names alone.
+ else if (out_attr[i].int_value() == in_attr[i].int_value())
+ {
+ // The output architecture has been changed to match the
+ // input architecture. Use the input names.
+ out_attr[elfcpp::Tag_CPU_name].set_string_value(
+ in_attr[elfcpp::Tag_CPU_name].string_value());
+ out_attr[elfcpp::Tag_CPU_raw_name].set_string_value(
+ in_attr[elfcpp::Tag_CPU_raw_name].string_value());
+ }
+ else
+ {
+ out_attr[elfcpp::Tag_CPU_name].set_string_value("");
+ out_attr[elfcpp::Tag_CPU_raw_name].set_string_value("");
+ }
+
+ // If we still don't have a value for Tag_CPU_name,
+ // make one up now. Tag_CPU_raw_name remains blank.
+ if (out_attr[elfcpp::Tag_CPU_name].string_value() == "")
+ {
+ const std::string cpu_name =
+ this->tag_cpu_name_value(out_attr[i].int_value());
+ // FIXME: If we see an unknown CPU, this will be set
+ // to "<unknown CPU n>", where n is the attribute value.
+ // This is different from BFD, which leaves the name alone.
+ out_attr[elfcpp::Tag_CPU_name].set_string_value(cpu_name);
+ }
+ }
+ break;
+
+ case elfcpp::Tag_ARM_ISA_use:
+ case elfcpp::Tag_THUMB_ISA_use:
+ case elfcpp::Tag_WMMX_arch:
+ case elfcpp::Tag_Advanced_SIMD_arch:
+ // ??? Do Advanced_SIMD (NEON) and WMMX conflict?
+ case elfcpp::Tag_ABI_FP_rounding:
+ case elfcpp::Tag_ABI_FP_exceptions:
+ case elfcpp::Tag_ABI_FP_user_exceptions:
+ case elfcpp::Tag_ABI_FP_number_model:
+ case elfcpp::Tag_VFP_HP_extension:
+ case elfcpp::Tag_CPU_unaligned_access:
+ case elfcpp::Tag_T2EE_use:
+ case elfcpp::Tag_Virtualization_use:
+ case elfcpp::Tag_MPextension_use:
+ // Use the largest value specified.
+ if (in_attr[i].int_value() > out_attr[i].int_value())
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ break;
+
+ case elfcpp::Tag_ABI_align8_preserved:
+ case elfcpp::Tag_ABI_PCS_RO_data:
+ // Use the smallest value specified.
+ if (in_attr[i].int_value() < out_attr[i].int_value())
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ break;
+
+ case elfcpp::Tag_ABI_align8_needed:
+ if ((in_attr[i].int_value() > 0 || out_attr[i].int_value() > 0)
+ && (in_attr[elfcpp::Tag_ABI_align8_preserved].int_value() == 0
+ || (out_attr[elfcpp::Tag_ABI_align8_preserved].int_value()
+ == 0)))
+ {
+ // This error message should be enabled once all non-conformant
+ // binaries in the toolchain have had the attributes set
+ // properly.
+ // gold_error(_("output 8-byte data alignment conflicts with %s"),
+ // name);
+ }
+ // Fall through.
+ case elfcpp::Tag_ABI_FP_denormal:
+ case elfcpp::Tag_ABI_PCS_GOT_use:
+ {
+ // These tags have 0 = don't care, 1 = strong requirement,
+ // 2 = weak requirement.
+ static const int order_021[3] = {0, 2, 1};
+
+ // Use the "greatest" from the sequence 0, 2, 1, or the largest
+ // value if greater than 2 (for future-proofing).
+ if ((in_attr[i].int_value() > 2
+ && in_attr[i].int_value() > out_attr[i].int_value())
+ || (in_attr[i].int_value() <= 2
+ && out_attr[i].int_value() <= 2
+ && (order_021[in_attr[i].int_value()]
+ > order_021[out_attr[i].int_value()])))
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ }
+ break;
+
+ case elfcpp::Tag_CPU_arch_profile:
+ if (out_attr[i].int_value() != in_attr[i].int_value())
+ {
+ // 0 will merge with anything.
+ // 'A' and 'S' merge to 'A'.
+ // 'R' and 'S' merge to 'R'.
+ // 'M' and 'A|R|S' is an error.
+ if (out_attr[i].int_value() == 0
+ || (out_attr[i].int_value() == 'S'
+ && (in_attr[i].int_value() == 'A'
+ || in_attr[i].int_value() == 'R')))
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ else if (in_attr[i].int_value() == 0
+ || (in_attr[i].int_value() == 'S'
+ && (out_attr[i].int_value() == 'A'
+ || out_attr[i].int_value() == 'R')))
+ ; // Do nothing.
+ else if (parameters->options().warn_mismatch())
+ {
+ gold_error
+ (_("conflicting architecture profiles %c/%c"),
+ in_attr[i].int_value() ? in_attr[i].int_value() : '0',
+ out_attr[i].int_value() ? out_attr[i].int_value() : '0');
+ }
+ }
+ break;
+ case elfcpp::Tag_VFP_arch:
+ {
+ static const struct
+ {
+ int ver;
+ int regs;
+ } vfp_versions[7] =
+ {
+ {0, 0},
+ {1, 16},
+ {2, 16},
+ {3, 32},
+ {3, 16},
+ {4, 32},
+ {4, 16}
+ };
+
+ // Values greater than 6 aren't defined, so just pick the
+ // biggest.
+ if (in_attr[i].int_value() > 6
+ && in_attr[i].int_value() > out_attr[i].int_value())
+ {
+ *out_attr = *in_attr;
+ break;
+ }
+ // The output uses the superset of input features
+ // (ISA version) and registers.
+ int ver = std::max(vfp_versions[in_attr[i].int_value()].ver,
+ vfp_versions[out_attr[i].int_value()].ver);
+ int regs = std::max(vfp_versions[in_attr[i].int_value()].regs,
+ vfp_versions[out_attr[i].int_value()].regs);
+ // This assumes all possible supersets are also a valid
+ // options.
+ int newval;
+ for (newval = 6; newval > 0; newval--)
+ {
+ if (regs == vfp_versions[newval].regs
+ && ver == vfp_versions[newval].ver)
+ break;
+ }
+ out_attr[i].set_int_value(newval);
+ }
+ break;
+ case elfcpp::Tag_PCS_config:
+ if (out_attr[i].int_value() == 0)
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ else if (in_attr[i].int_value() != 0
+ && out_attr[i].int_value() != 0
+ && parameters->options().warn_mismatch())
+ {
+ // It's sometimes ok to mix different configs, so this is only
+ // a warning.
+ gold_warning(_("%s: conflicting platform configuration"), name);
+ }
+ break;
+ case elfcpp::Tag_ABI_PCS_R9_use:
+ if (in_attr[i].int_value() != out_attr[i].int_value()
+ && out_attr[i].int_value() != elfcpp::AEABI_R9_unused
+ && in_attr[i].int_value() != elfcpp::AEABI_R9_unused
+ && parameters->options().warn_mismatch())
+ {
+ gold_error(_("%s: conflicting use of R9"), name);
+ }
+ if (out_attr[i].int_value() == elfcpp::AEABI_R9_unused)
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ break;
+ case elfcpp::Tag_ABI_PCS_RW_data:
+ if (in_attr[i].int_value() == elfcpp::AEABI_PCS_RW_data_SBrel
+ && (in_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
+ != elfcpp::AEABI_R9_SB)
+ && (out_attr[elfcpp::Tag_ABI_PCS_R9_use].int_value()
+ != elfcpp::AEABI_R9_unused)
+ && parameters->options().warn_mismatch())
+ {
+ gold_error(_("%s: SB relative addressing conflicts with use "
+ "of R9"),
+ name);
+ }
+ // Use the smallest value specified.
+ if (in_attr[i].int_value() < out_attr[i].int_value())
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ break;
+ case elfcpp::Tag_ABI_PCS_wchar_t:
+ // FIXME: Make it possible to turn off this warning.
+ if (out_attr[i].int_value()
+ && in_attr[i].int_value()
+ && out_attr[i].int_value() != in_attr[i].int_value()
+ && parameters->options().warn_mismatch())
+ {
+ gold_warning(_("%s uses %u-byte wchar_t yet the output is to "
+ "use %u-byte wchar_t; use of wchar_t values "
+ "across objects may fail"),
+ name, in_attr[i].int_value(),
+ out_attr[i].int_value());
+ }
+ else if (in_attr[i].int_value() && !out_attr[i].int_value())
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ break;
+ case elfcpp::Tag_ABI_enum_size:
+ if (in_attr[i].int_value() != elfcpp::AEABI_enum_unused)
+ {
+ if (out_attr[i].int_value() == elfcpp::AEABI_enum_unused
+ || out_attr[i].int_value() == elfcpp::AEABI_enum_forced_wide)
+ {
+ // The existing object is compatible with anything.
+ // Use whatever requirements the new object has.
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ }
+ // FIXME: Make it possible to turn off this warning.
+ else if (in_attr[i].int_value() != elfcpp::AEABI_enum_forced_wide
+ && out_attr[i].int_value() != in_attr[i].int_value()
+ && parameters->options().warn_mismatch())
+ {
+ unsigned int in_value = in_attr[i].int_value();
+ unsigned int out_value = out_attr[i].int_value();
+ gold_warning(_("%s uses %s enums yet the output is to use "
+ "%s enums; use of enum values across objects "
+ "may fail"),
+ name,
+ this->aeabi_enum_name(in_value).c_str(),
+ this->aeabi_enum_name(out_value).c_str());
+ }
+ }
+ break;
+ case elfcpp::Tag_ABI_VFP_args:
+ // Aready done.
+ break;
+ case elfcpp::Tag_ABI_WMMX_args:
+ if (in_attr[i].int_value() != out_attr[i].int_value()
+ && parameters->options().warn_mismatch())
+ {
+ gold_error(_("%s uses iWMMXt register arguments, output does "
+ "not"),
+ name);
+ }
+ break;
+ case Object_attribute::Tag_compatibility:
+ // Merged in target-independent code.
+ break;
+ case elfcpp::Tag_ABI_HardFP_use:
+ // 1 (SP) and 2 (DP) conflict, so combine to 3 (SP & DP).
+ if ((in_attr[i].int_value() == 1 && out_attr[i].int_value() == 2)
+ || (in_attr[i].int_value() == 2 && out_attr[i].int_value() == 1))
+ out_attr[i].set_int_value(3);
+ else if (in_attr[i].int_value() > out_attr[i].int_value())
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ break;
+ case elfcpp::Tag_ABI_FP_16bit_format:
+ if (in_attr[i].int_value() != 0 && out_attr[i].int_value() != 0)
+ {
+ if (in_attr[i].int_value() != out_attr[i].int_value()
+ && parameters->options().warn_mismatch())
+ gold_error(_("fp16 format mismatch between %s and output"),
+ name);
+ }
+ if (in_attr[i].int_value() != 0)
+ out_attr[i].set_int_value(in_attr[i].int_value());
+ break;
+
+ case elfcpp::Tag_DIV_use:
+ // This tag is set to zero if we can use UDIV and SDIV in Thumb
+ // mode on a v7-M or v7-R CPU; to one if we can not use UDIV or
+ // SDIV at all; and to two if we can use UDIV or SDIV on a v7-A
+ // CPU. We will merge as follows: If the input attribute's value
+ // is one then the output attribute's value remains unchanged. If
+ // the input attribute's value is zero or two then if the output
+ // attribute's value is one the output value is set to the input
+ // value, otherwise the output value must be the same as the
+ // inputs. */
+ if (in_attr[i].int_value() != 1 && out_attr[i].int_value() != 1)
+ {
+ if (in_attr[i].int_value() != out_attr[i].int_value())
+ {
+ gold_error(_("DIV usage mismatch between %s and output"),
+ name);
+ }
+ }
+
+ if (in_attr[i].int_value() != 1)
+ out_attr[i].set_int_value(in_attr[i].int_value());
+
+ break;
+
+ case elfcpp::Tag_MPextension_use_legacy:
+ // We don't output objects with Tag_MPextension_use_legacy - we
+ // move the value to Tag_MPextension_use.
+ if (in_attr[i].int_value() != 0
+ && in_attr[elfcpp::Tag_MPextension_use].int_value() != 0)
+ {
+ if (in_attr[elfcpp::Tag_MPextension_use].int_value()
+ != in_attr[i].int_value())
+ {
+ gold_error(_("%s has has both the current and legacy "
+ "Tag_MPextension_use attributes"),
+ name);
+ }
+ }
+
+ if (in_attr[i].int_value()
+ > out_attr[elfcpp::Tag_MPextension_use].int_value())
+ out_attr[elfcpp::Tag_MPextension_use] = in_attr[i];
+
+ break;
+
+ case elfcpp::Tag_nodefaults:
+ // This tag is set if it exists, but the value is unused (and is
+ // typically zero). We don't actually need to do anything here -
+ // the merge happens automatically when the type flags are merged
+ // below.
+ break;
+ case elfcpp::Tag_also_compatible_with:
+ // Already done in Tag_CPU_arch.
+ break;
+ case elfcpp::Tag_conformance:
+ // Keep the attribute if it matches. Throw it away otherwise.
+ // No attribute means no claim to conform.
+ if (in_attr[i].string_value() != out_attr[i].string_value())
+ out_attr[i].set_string_value("");
+ break;
+
+ default:
+ {
+ const char* err_object = NULL;
+
+ // The "known_obj_attributes" table does contain some undefined
+ // attributes. Ensure that there are unused.
+ if (out_attr[i].int_value() != 0
+ || out_attr[i].string_value() != "")
+ err_object = "output";
+ else if (in_attr[i].int_value() != 0
+ || in_attr[i].string_value() != "")
+ err_object = name;
+
+ if (err_object != NULL
+ && parameters->options().warn_mismatch())
+ {
+ // Attribute numbers >=64 (mod 128) can be safely ignored.
+ if ((i & 127) < 64)
+ gold_error(_("%s: unknown mandatory EABI object attribute "
+ "%d"),
+ err_object, i);
+ else
+ gold_warning(_("%s: unknown EABI object attribute %d"),
+ err_object, i);
+ }
+
+ // Only pass on attributes that match in both inputs.
+ if (!in_attr[i].matches(out_attr[i]))
+ {
+ out_attr[i].set_int_value(0);
+ out_attr[i].set_string_value("");
+ }
+ }
}
+
+ // If out_attr was copied from in_attr then it won't have a type yet.
+ if (in_attr[i].type() && !out_attr[i].type())
+ out_attr[i].set_type(in_attr[i].type());
}
- // Emit any relocs we saved in an attempt to avoid generating COPY
- // relocs.
- if (this->copy_relocs_.any_saved_relocs())
- this->copy_relocs_.emit(this->rel_dyn_section(layout));
+ // Merge Tag_compatibility attributes and any common GNU ones.
+ this->attributes_section_data_->merge(name, pasd);
- // For the ARM target, we need to add a PT_ARM_EXIDX segment for
- // the .ARM.exidx section.
- if (!layout->script_options()->saw_phdrs_clause()
- && !parameters->options().relocatable())
+ // Check for any attributes not known on ARM.
+ typedef Vendor_object_attributes::Other_attributes Other_attributes;
+ const Other_attributes* in_other_attributes = pasd->other_attributes(vendor);
+ Other_attributes::const_iterator in_iter = in_other_attributes->begin();
+ Other_attributes* out_other_attributes =
+ this->attributes_section_data_->other_attributes(vendor);
+ Other_attributes::iterator out_iter = out_other_attributes->begin();
+
+ while (in_iter != in_other_attributes->end()
+ || out_iter != out_other_attributes->end())
{
- Output_section* exidx_section =
- layout->find_output_section(".ARM.exidx");
+ const char* err_object = NULL;
+ int err_tag = 0;
+
+ // The tags for each list are in numerical order.
+ // If the tags are equal, then merge.
+ if (out_iter != out_other_attributes->end()
+ && (in_iter == in_other_attributes->end()
+ || in_iter->first > out_iter->first))
+ {
+ // This attribute only exists in output. We can't merge, and we
+ // don't know what the tag means, so delete it.
+ err_object = "output";
+ err_tag = out_iter->first;
+ int saved_tag = out_iter->first;
+ delete out_iter->second;
+ out_other_attributes->erase(out_iter);
+ out_iter = out_other_attributes->upper_bound(saved_tag);
+ }
+ else if (in_iter != in_other_attributes->end()
+ && (out_iter != out_other_attributes->end()
+ || in_iter->first < out_iter->first))
+ {
+ // This attribute only exists in input. We can't merge, and we
+ // don't know what the tag means, so ignore it.
+ err_object = name;
+ err_tag = in_iter->first;
+ ++in_iter;
+ }
+ else // The tags are equal.
+ {
+ // As present, all attributes in the list are unknown, and
+ // therefore can't be merged meaningfully.
+ err_object = "output";
+ err_tag = out_iter->first;
+
+ // Only pass on attributes that match in both inputs.
+ if (!in_iter->second->matches(*(out_iter->second)))
+ {
+ // No match. Delete the attribute.
+ int saved_tag = out_iter->first;
+ delete out_iter->second;
+ out_other_attributes->erase(out_iter);
+ out_iter = out_other_attributes->upper_bound(saved_tag);
+ }
+ else
+ {
+ // Matched. Keep the attribute and move to the next.
+ ++out_iter;
+ ++in_iter;
+ }
+ }
- if (exidx_section != NULL
- && exidx_section->type() == elfcpp::SHT_ARM_EXIDX)
+ if (err_object && parameters->options().warn_mismatch())
{
- gold_assert(layout->find_output_segment(elfcpp::PT_ARM_EXIDX, 0, 0)
- == NULL);
- Output_segment* exidx_segment =
- layout->make_output_segment(elfcpp::PT_ARM_EXIDX, elfcpp::PF_R);
- exidx_segment->add_output_section(exidx_section, elfcpp::PF_R);
+ // Attribute numbers >=64 (mod 128) can be safely ignored. */
+ if ((err_tag & 127) < 64)
+ {
+ gold_error(_("%s: unknown mandatory EABI object attribute %d"),
+ err_object, err_tag);
+ }
+ else
+ {
+ gold_warning(_("%s: unknown EABI object attribute %d"),
+ err_object, err_tag);
+ }
}
}
}
-// Return whether a direct absolute static relocation needs to be applied.
-// In cases where Scan::local() or Scan::global() has created
-// a dynamic relocation other than R_ARM_RELATIVE, the addend
-// of the relocation is carried in the data, and we must not
-// apply the static relocation.
+// Stub-generation methods for Target_arm.
+
+// Make a new Arm_input_section object.
template<bool big_endian>
-inline bool
-Target_arm<big_endian>::Relocate::should_apply_static_reloc(
- const Sized_symbol<32>* gsym,
- int ref_flags,
- bool is_32bit,
- Output_section* output_section)
+Arm_input_section<big_endian>*
+Target_arm<big_endian>::new_arm_input_section(
+ Relobj* relobj,
+ unsigned int shndx)
{
- // If the output section is not allocated, then we didn't call
- // scan_relocs, we didn't create a dynamic reloc, and we must apply
- // the reloc here.
- if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
- return true;
+ Section_id sid(relobj, shndx);
- // For local symbols, we will have created a non-RELATIVE dynamic
- // relocation only if (a) the output is position independent,
- // (b) the relocation is absolute (not pc- or segment-relative), and
- // (c) the relocation is not 32 bits wide.
- if (gsym == NULL)
- return !(parameters->options().output_is_position_independent()
- && (ref_flags & Symbol::ABSOLUTE_REF)
- && !is_32bit);
+ Arm_input_section<big_endian>* arm_input_section =
+ new Arm_input_section<big_endian>(relobj, shndx);
+ arm_input_section->init();
+
+ // Register new Arm_input_section in map for look-up.
+ std::pair<typename Arm_input_section_map::iterator, bool> ins =
+ this->arm_input_section_map_.insert(std::make_pair(sid, arm_input_section));
+
+ // Make sure that it we have not created another Arm_input_section
+ // for this input section already.
+ gold_assert(ins.second);
+
+ return arm_input_section;
+}
+
+// Find the Arm_input_section object corresponding to the SHNDX-th input
+// section of RELOBJ.
+
+template<bool big_endian>
+Arm_input_section<big_endian>*
+Target_arm<big_endian>::find_arm_input_section(
+ Relobj* relobj,
+ unsigned int shndx) const
+{
+ Section_id sid(relobj, shndx);
+ typename Arm_input_section_map::const_iterator p =
+ this->arm_input_section_map_.find(sid);
+ return (p != this->arm_input_section_map_.end()) ? p->second : NULL;
+}
- // For global symbols, we use the same helper routines used in the
- // scan pass. If we did not create a dynamic relocation, or if we
- // created a RELATIVE dynamic relocation, we should apply the static
- // relocation.
- bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
- bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
- && gsym->can_use_relative_reloc(ref_flags
- & Symbol::FUNCTION_CALL);
- return !has_dyn || is_rel;
+// Make a new stub table.
+
+template<bool big_endian>
+Stub_table<big_endian>*
+Target_arm<big_endian>::new_stub_table(Arm_input_section<big_endian>* owner)
+{
+ Stub_table<big_endian>* stub_table =
+ new Stub_table<big_endian>(owner);
+ this->stub_tables_.push_back(stub_table);
+
+ stub_table->set_address(owner->address() + owner->data_size());
+ stub_table->set_file_offset(owner->offset() + owner->data_size());
+ stub_table->finalize_data_size();
+
+ return stub_table;
}
-// Perform a relocation.
+// Scan a relocation for stub generation.
template<bool big_endian>
-inline bool
-Target_arm<big_endian>::Relocate::relocate(
+void
+Target_arm<big_endian>::scan_reloc_for_stub(
const Relocate_info<32, big_endian>* relinfo,
- Target_arm* target,
- Output_section *output_section,
- size_t relnum,
- const elfcpp::Rel<32, big_endian>& rel,
unsigned int r_type,
const Sized_symbol<32>* gsym,
+ unsigned int r_sym,
const Symbol_value<32>* psymval,
- unsigned char* view,
- elfcpp::Elf_types<32>::Elf_Addr address,
- section_size_type /* view_size */ )
+ elfcpp::Elf_types<32>::Elf_Swxword addend,
+ Arm_address address)
{
- typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
-
- r_type = get_real_reloc_type(r_type);
+ typedef typename Target_arm<big_endian>::Relocate Relocate;
- // If this the symbol may be a Thumb function, set thumb bit to 1.
- bool has_thumb_bit = ((gsym != NULL)
- && (gsym->type() == elfcpp::STT_FUNC
- || gsym->type() == elfcpp::STT_ARM_TFUNC));
+ const Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
- // Pick the value to use for symbols defined in shared objects.
+ bool target_is_thumb;
Symbol_value<32> symval;
- if (gsym != NULL
- && gsym->use_plt_offset(reloc_is_non_pic(r_type)))
- {
- symval.set_output_value(target->plt_section()->address()
- + gsym->plt_offset());
- psymval = &symval;
- has_thumb_bit = 0;
- }
-
- const Sized_relobj<32, big_endian>* object = relinfo->object;
-
- // Get the GOT offset if needed.
- // The GOT pointer points to the end of the GOT section.
- // We need to subtract the size of the GOT section to get
- // the actual offset to use in the relocation.
- bool have_got_offset = false;
- unsigned int got_offset = 0;
- switch (r_type)
+ if (gsym != NULL)
{
- case elfcpp::R_ARM_GOT_BREL:
- case elfcpp::R_ARM_GOT_PREL:
- if (gsym != NULL)
+ // This is a global symbol. Determine if we use PLT and if the
+ // final target is THUMB.
+ if (gsym->use_plt_offset(Relocate::reloc_is_non_pic(r_type)))
{
- gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
- got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
- - target->got_size());
+ // This uses a PLT, change the symbol value.
+ symval.set_output_value(this->plt_section()->address()
+ + gsym->plt_offset());
+ psymval = &symval;
+ target_is_thumb = false;
}
+ else if (gsym->is_undefined())
+ // There is no need to generate a stub symbol is undefined.
+ return;
else
{
- unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
- gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
- got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
- - target->got_size());
+ target_is_thumb =
+ ((gsym->type() == elfcpp::STT_ARM_TFUNC)
+ || (gsym->type() == elfcpp::STT_FUNC
+ && !gsym->is_undefined()
+ && ((psymval->value(arm_relobj, 0) & 1) != 0)));
}
- have_got_offset = true;
- break;
-
- default:
- break;
}
-
- typename Arm_relocate_functions::Status reloc_status =
- Arm_relocate_functions::STATUS_OKAY;
- switch (r_type)
+ else
{
- case elfcpp::R_ARM_NONE:
- break;
-
- case elfcpp::R_ARM_ABS8:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
- output_section))
- reloc_status = Arm_relocate_functions::abs8(view, object, psymval);
- break;
-
- case elfcpp::R_ARM_ABS12:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
- output_section))
- reloc_status = Arm_relocate_functions::abs12(view, object, psymval);
- break;
-
- case elfcpp::R_ARM_ABS16:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
- output_section))
- reloc_status = Arm_relocate_functions::abs16(view, object, psymval);
- break;
-
- case elfcpp::R_ARM_ABS32:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
- output_section))
- reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
- has_thumb_bit);
- break;
-
- case elfcpp::R_ARM_ABS32_NOI:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
- output_section))
- // No thumb bit for this relocation: (S + A)
- reloc_status = Arm_relocate_functions::abs32(view, object, psymval,
- false);
- break;
+ // This is a local symbol. Determine if the final target is THUMB.
+ target_is_thumb = arm_relobj->local_symbol_is_thumb_function(r_sym);
+ }
- case elfcpp::R_ARM_MOVW_ABS_NC:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
- output_section))
- reloc_status = Arm_relocate_functions::movw_abs_nc(view, object,
- psymval,
- has_thumb_bit);
- else
- gold_error(_("relocation R_ARM_MOVW_ABS_NC cannot be used when making"
- "a shared object; recompile with -fPIC"));
- break;
+ // Strip LSB if this points to a THUMB target.
+ const Arm_reloc_property* reloc_property =
+ arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
+ gold_assert(reloc_property != NULL);
+ if (target_is_thumb
+ && reloc_property->uses_thumb_bit()
+ && ((psymval->value(arm_relobj, 0) & 1) != 0))
+ {
+ Arm_address stripped_value =
+ psymval->value(arm_relobj, 0) & ~static_cast<Arm_address>(1);
+ symval.set_output_value(stripped_value);
+ psymval = &symval;
+ }
- case elfcpp::R_ARM_MOVT_ABS:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
- output_section))
- reloc_status = Arm_relocate_functions::movt_abs(view, object, psymval);
- else
- gold_error(_("relocation R_ARM_MOVT_ABS cannot be used when making"
- "a shared object; recompile with -fPIC"));
- break;
+ // Get the symbol value.
+ Symbol_value<32>::Value value = psymval->value(arm_relobj, 0);
- case elfcpp::R_ARM_THM_MOVW_ABS_NC:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
- output_section))
- reloc_status = Arm_relocate_functions::thm_movw_abs_nc(view, object,
- psymval,
- has_thumb_bit);
- else
- gold_error(_("relocation R_ARM_THM_MOVW_ABS_NC cannot be used when"
- "making a shared object; recompile with -fPIC"));
+ // Owing to pipelining, the PC relative branches below actually skip
+ // two instructions when the branch offset is 0.
+ Arm_address destination;
+ switch (r_type)
+ {
+ case elfcpp::R_ARM_CALL:
+ case elfcpp::R_ARM_JUMP24:
+ case elfcpp::R_ARM_PLT32:
+ // ARM branches.
+ destination = value + addend + 8;
break;
-
- case elfcpp::R_ARM_THM_MOVT_ABS:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
- output_section))
- reloc_status = Arm_relocate_functions::thm_movt_abs(view, object,
- psymval);
- else
- gold_error(_("relocation R_ARM_THM_MOVT_ABS cannot be used when"
- "making a shared object; recompile with -fPIC"));
+ case elfcpp::R_ARM_THM_CALL:
+ case elfcpp::R_ARM_THM_XPC22:
+ case elfcpp::R_ARM_THM_JUMP24:
+ case elfcpp::R_ARM_THM_JUMP19:
+ // THUMB branches.
+ destination = value + addend + 4;
break;
+ default:
+ gold_unreachable();
+ }
- case elfcpp::R_ARM_MOVW_PREL_NC:
- reloc_status = Arm_relocate_functions::movw_prel_nc(view, object,
- psymval, address,
- has_thumb_bit);
- break;
+ Reloc_stub* stub = NULL;
+ Stub_type stub_type =
+ Reloc_stub::stub_type_for_reloc(r_type, address, destination,
+ target_is_thumb);
+ if (stub_type != arm_stub_none)
+ {
+ // Try looking up an existing stub from a stub table.
+ Stub_table<big_endian>* stub_table =
+ arm_relobj->stub_table(relinfo->data_shndx);
+ gold_assert(stub_table != NULL);
+
+ // Locate stub by destination.
+ Reloc_stub::Key stub_key(stub_type, gsym, arm_relobj, r_sym, addend);
+
+ // Create a stub if there is not one already
+ stub = stub_table->find_reloc_stub(stub_key);
+ if (stub == NULL)
+ {
+ // create a new stub and add it to stub table.
+ stub = this->stub_factory().make_reloc_stub(stub_type);
+ stub_table->add_reloc_stub(stub, stub_key);
+ }
- case elfcpp::R_ARM_MOVT_PREL:
- reloc_status = Arm_relocate_functions::movt_prel(view, object,
- psymval, address);
- break;
+ // Record the destination address.
+ stub->set_destination_address(destination
+ | (target_is_thumb ? 1 : 0));
+ }
- case elfcpp::R_ARM_THM_MOVW_PREL_NC:
- reloc_status = Arm_relocate_functions::thm_movw_prel_nc(view, object,
- psymval, address,
- has_thumb_bit);
- break;
+ // For Cortex-A8, we need to record a relocation at 4K page boundary.
+ if (this->fix_cortex_a8_
+ && (r_type == elfcpp::R_ARM_THM_JUMP24
+ || r_type == elfcpp::R_ARM_THM_JUMP19
+ || r_type == elfcpp::R_ARM_THM_CALL
+ || r_type == elfcpp::R_ARM_THM_XPC22)
+ && (address & 0xfffU) == 0xffeU)
+ {
+ // Found a candidate. Note we haven't checked the destination is
+ // within 4K here: if we do so (and don't create a record) we can't
+ // tell that a branch should have been relocated when scanning later.
+ this->cortex_a8_relocs_info_[address] =
+ new Cortex_a8_reloc(stub, r_type,
+ destination | (target_is_thumb ? 1 : 0));
+ }
+}
- case elfcpp::R_ARM_THM_MOVT_PREL:
- reloc_status = Arm_relocate_functions::thm_movt_prel(view, object,
- psymval, address);
- break;
-
- case elfcpp::R_ARM_REL32:
- reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
- address, has_thumb_bit);
- break;
+// This function scans a relocation sections for stub generation.
+// The template parameter Relocate must be a class type which provides
+// a single function, relocate(), which implements the machine
+// specific part of a relocation.
- case elfcpp::R_ARM_THM_ABS5:
- if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
- output_section))
- reloc_status = Arm_relocate_functions::thm_abs5(view, object, psymval);
- break;
+// BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
+// SHT_REL or SHT_RELA.
- case elfcpp::R_ARM_THM_CALL:
- reloc_status = Arm_relocate_functions::thm_call(view, object, psymval,
- address, has_thumb_bit);
- break;
+// PRELOCS points to the relocation data. RELOC_COUNT is the number
+// of relocs. OUTPUT_SECTION is the output section.
+// NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
+// mapped to output offsets.
- case elfcpp::R_ARM_GOTOFF32:
- {
- elfcpp::Elf_types<32>::Elf_Addr got_origin;
- got_origin = target->got_plt_section()->address();
- reloc_status = Arm_relocate_functions::rel32(view, object, psymval,
- got_origin, has_thumb_bit);
- }
- break;
+// VIEW is the section data, VIEW_ADDRESS is its memory address, and
+// VIEW_SIZE is the size. These refer to the input section, unless
+// NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
+// the output section.
- case elfcpp::R_ARM_BASE_PREL:
- {
- uint32_t origin;
- // Get the addressing origin of the output segment defining the
- // symbol gsym (AAELF 4.6.1.2 Relocation types)
- gold_assert(gsym != NULL);
- if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
- origin = gsym->output_segment()->vaddr();
- else if (gsym->source () == Symbol::IN_OUTPUT_DATA)
- origin = gsym->output_data()->address();
- else
- {
- gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
- _("cannot find origin of R_ARM_BASE_PREL"));
- return true;
- }
- reloc_status = Arm_relocate_functions::base_prel(view, origin, address);
- }
- break;
+template<bool big_endian>
+template<int sh_type>
+void inline
+Target_arm<big_endian>::scan_reloc_section_for_stubs(
+ const Relocate_info<32, big_endian>* relinfo,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ bool needs_special_offset_handling,
+ const unsigned char* view,
+ elfcpp::Elf_types<32>::Elf_Addr view_address,
+ section_size_type)
+{
+ typedef typename Reloc_types<sh_type, 32, big_endian>::Reloc Reltype;
+ const int reloc_size =
+ Reloc_types<sh_type, 32, big_endian>::reloc_size;
- case elfcpp::R_ARM_BASE_ABS:
- {
- if (!should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
- output_section))
- break;
+ Arm_relobj<big_endian>* arm_object =
+ Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
+ unsigned int local_count = arm_object->local_symbol_count();
- uint32_t origin;
- // Get the addressing origin of the output segment defining
- // the symbol gsym (AAELF 4.6.1.2 Relocation types).
- if (gsym == NULL)
- // R_ARM_BASE_ABS with the NULL symbol will give the
- // absolute address of the GOT origin (GOT_ORG) (see ARM IHI
- // 0044C (AAELF): 4.6.1.8 Proxy generating relocations).
- origin = target->got_plt_section()->address();
- else if (gsym->source() == Symbol::IN_OUTPUT_SEGMENT)
- origin = gsym->output_segment()->vaddr();
- else if (gsym->source () == Symbol::IN_OUTPUT_DATA)
- origin = gsym->output_data()->address();
- else
- {
- gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
- _("cannot find origin of R_ARM_BASE_ABS"));
- return true;
- }
+ Comdat_behavior comdat_behavior = CB_UNDETERMINED;
- reloc_status = Arm_relocate_functions::base_abs(view, origin);
- }
- break;
+ for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
+ {
+ Reltype reloc(prelocs);
- case elfcpp::R_ARM_GOT_BREL:
- gold_assert(have_got_offset);
- reloc_status = Arm_relocate_functions::got_brel(view, got_offset);
- break;
+ typename elfcpp::Elf_types<32>::Elf_WXword r_info = reloc.get_r_info();
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
+ unsigned int r_type = elfcpp::elf_r_type<32>(r_info);
- case elfcpp::R_ARM_GOT_PREL:
- gold_assert(have_got_offset);
- // Get the address origin for GOT PLT, which is allocated right
- // after the GOT section, to calculate an absolute address of
- // the symbol GOT entry (got_origin + got_offset).
- elfcpp::Elf_types<32>::Elf_Addr got_origin;
- got_origin = target->got_plt_section()->address();
- reloc_status = Arm_relocate_functions::got_prel(view,
- got_origin + got_offset,
- address);
- break;
+ r_type = this->get_real_reloc_type(r_type);
- case elfcpp::R_ARM_PLT32:
- gold_assert(gsym == NULL
- || gsym->has_plt_offset()
- || gsym->final_value_is_known()
- || (gsym->is_defined()
- && !gsym->is_from_dynobj()
- && !gsym->is_preemptible()));
- reloc_status = Arm_relocate_functions::plt32(view, object, psymval,
- address, has_thumb_bit);
- break;
+ // Only a few relocation types need stubs.
+ if ((r_type != elfcpp::R_ARM_CALL)
+ && (r_type != elfcpp::R_ARM_JUMP24)
+ && (r_type != elfcpp::R_ARM_PLT32)
+ && (r_type != elfcpp::R_ARM_THM_CALL)
+ && (r_type != elfcpp::R_ARM_THM_XPC22)
+ && (r_type != elfcpp::R_ARM_THM_JUMP24)
+ && (r_type != elfcpp::R_ARM_THM_JUMP19)
+ && (r_type != elfcpp::R_ARM_V4BX))
+ continue;
- case elfcpp::R_ARM_CALL:
- reloc_status = Arm_relocate_functions::call(view, object, psymval,
- address, has_thumb_bit);
- break;
+ section_offset_type offset =
+ convert_to_section_size_type(reloc.get_r_offset());
- case elfcpp::R_ARM_JUMP24:
- reloc_status = Arm_relocate_functions::jump24(view, object, psymval,
- address, has_thumb_bit);
- break;
+ if (needs_special_offset_handling)
+ {
+ offset = output_section->output_offset(relinfo->object,
+ relinfo->data_shndx,
+ offset);
+ if (offset == -1)
+ continue;
+ }
- case elfcpp::R_ARM_PREL31:
- reloc_status = Arm_relocate_functions::prel31(view, object, psymval,
- address, has_thumb_bit);
- break;
+ // Create a v4bx stub if --fix-v4bx-interworking is used.
+ if (r_type == elfcpp::R_ARM_V4BX)
+ {
+ if (this->fix_v4bx() == General_options::FIX_V4BX_INTERWORKING)
+ {
+ // Get the BX instruction.
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ const Valtype* wv =
+ reinterpret_cast<const Valtype*>(view + offset);
+ elfcpp::Elf_types<32>::Elf_Swxword insn =
+ elfcpp::Swap<32, big_endian>::readval(wv);
+ const uint32_t reg = (insn & 0xf);
+
+ if (reg < 0xf)
+ {
+ // Try looking up an existing stub from a stub table.
+ Stub_table<big_endian>* stub_table =
+ arm_object->stub_table(relinfo->data_shndx);
+ gold_assert(stub_table != NULL);
+
+ if (stub_table->find_arm_v4bx_stub(reg) == NULL)
+ {
+ // create a new stub and add it to stub table.
+ Arm_v4bx_stub* stub =
+ this->stub_factory().make_arm_v4bx_stub(reg);
+ gold_assert(stub != NULL);
+ stub_table->add_arm_v4bx_stub(stub);
+ }
+ }
+ }
+ continue;
+ }
- case elfcpp::R_ARM_TARGET1:
- // This should have been mapped to another type already.
- // Fall through.
- case elfcpp::R_ARM_COPY:
- case elfcpp::R_ARM_GLOB_DAT:
- case elfcpp::R_ARM_JUMP_SLOT:
- case elfcpp::R_ARM_RELATIVE:
- // These are relocations which should only be seen by the
- // dynamic linker, and should never be seen here.
- gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
- _("unexpected reloc %u in object file"),
- r_type);
- break;
+ // Get the addend.
+ Stub_addend_reader<sh_type, big_endian> stub_addend_reader;
+ elfcpp::Elf_types<32>::Elf_Swxword addend =
+ stub_addend_reader(r_type, view + offset, reloc);
- default:
- gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
- _("unsupported reloc %u"),
- r_type);
- break;
- }
+ const Sized_symbol<32>* sym;
- // Report any errors.
- switch (reloc_status)
- {
- case Arm_relocate_functions::STATUS_OKAY:
- break;
- case Arm_relocate_functions::STATUS_OVERFLOW:
- gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
- _("relocation overflow in relocation %u"),
- r_type);
- break;
- case Arm_relocate_functions::STATUS_BAD_RELOC:
- gold_error_at_location(
- relinfo,
- relnum,
- rel.get_r_offset(),
- _("unexpected opcode while processing relocation %u"),
- r_type);
- break;
- default:
- gold_unreachable();
- }
+ Symbol_value<32> symval;
+ const Symbol_value<32> *psymval;
+ if (r_sym < local_count)
+ {
+ sym = NULL;
+ psymval = arm_object->local_symbol(r_sym);
+
+ // If the local symbol belongs to a section we are discarding,
+ // and that section is a debug section, try to find the
+ // corresponding kept section and map this symbol to its
+ // counterpart in the kept section. The symbol must not
+ // correspond to a section we are folding.
+ bool is_ordinary;
+ unsigned int shndx = psymval->input_shndx(&is_ordinary);
+ if (is_ordinary
+ && shndx != elfcpp::SHN_UNDEF
+ && !arm_object->is_section_included(shndx)
+ && !(relinfo->symtab->is_section_folded(arm_object, shndx)))
+ {
+ if (comdat_behavior == CB_UNDETERMINED)
+ {
+ std::string name =
+ arm_object->section_name(relinfo->data_shndx);
+ comdat_behavior = get_comdat_behavior(name.c_str());
+ }
+ if (comdat_behavior == CB_PRETEND)
+ {
+ bool found;
+ typename elfcpp::Elf_types<32>::Elf_Addr value =
+ arm_object->map_to_kept_section(shndx, &found);
+ if (found)
+ symval.set_output_value(value + psymval->input_value());
+ else
+ symval.set_output_value(0);
+ }
+ else
+ {
+ symval.set_output_value(0);
+ }
+ symval.set_no_output_symtab_entry();
+ psymval = &symval;
+ }
+ }
+ else
+ {
+ const Symbol* gsym = arm_object->global_symbol(r_sym);
+ gold_assert(gsym != NULL);
+ if (gsym->is_forwarder())
+ gsym = relinfo->symtab->resolve_forwards(gsym);
+
+ sym = static_cast<const Sized_symbol<32>*>(gsym);
+ if (sym->has_symtab_index())
+ symval.set_output_symtab_index(sym->symtab_index());
+ else
+ symval.set_no_output_symtab_entry();
+
+ // We need to compute the would-be final value of this global
+ // symbol.
+ const Symbol_table* symtab = relinfo->symtab;
+ const Sized_symbol<32>* sized_symbol =
+ symtab->get_sized_symbol<32>(gsym);
+ Symbol_table::Compute_final_value_status status;
+ Arm_address value =
+ symtab->compute_final_value<32>(sized_symbol, &status);
+
+ // Skip this if the symbol has not output section.
+ if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
+ continue;
+
+ symval.set_output_value(value);
+ psymval = &symval;
+ }
- return true;
+ // If symbol is a section symbol, we don't know the actual type of
+ // destination. Give up.
+ if (psymval->is_section_symbol())
+ continue;
+
+ this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
+ addend, view_address + offset);
+ }
}
-// Relocate section data.
+// Scan an input section for stub generation.
template<bool big_endian>
void
-Target_arm<big_endian>::relocate_section(
+Target_arm<big_endian>::scan_section_for_stubs(
const Relocate_info<32, big_endian>* relinfo,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
- unsigned char* view,
- elfcpp::Elf_types<32>::Elf_Addr address,
- section_size_type view_size,
- const Reloc_symbol_changes* reloc_symbol_changes)
+ const unsigned char* view,
+ Arm_address view_address,
+ section_size_type view_size)
{
- typedef typename Target_arm<big_endian>::Relocate Arm_relocate;
- gold_assert(sh_type == elfcpp::SHT_REL);
+ if (sh_type == elfcpp::SHT_REL)
+ this->scan_reloc_section_for_stubs<elfcpp::SHT_REL>(
+ relinfo,
+ prelocs,
+ reloc_count,
+ output_section,
+ needs_special_offset_handling,
+ view,
+ view_address,
+ view_size);
+ else if (sh_type == elfcpp::SHT_RELA)
+ // We do not support RELA type relocations yet. This is provided for
+ // completeness.
+ this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
+ relinfo,
+ prelocs,
+ reloc_count,
+ output_section,
+ needs_special_offset_handling,
+ view,
+ view_address,
+ view_size);
+ else
+ gold_unreachable();
+}
- gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
- Arm_relocate>(
- relinfo,
- this,
- prelocs,
- reloc_count,
- output_section,
- needs_special_offset_handling,
- view,
- address,
- view_size,
- reloc_symbol_changes);
+// Group input sections for stub generation.
+//
+// We goup input sections in an output sections so that the total size,
+// including any padding space due to alignment is smaller than GROUP_SIZE
+// unless the only input section in group is bigger than GROUP_SIZE already.
+// Then an ARM stub table is created to follow the last input section
+// in group. For each group an ARM stub table is created an is placed
+// after the last group. If STUB_ALWATS_AFTER_BRANCH is false, we further
+// extend the group after the stub table.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::group_sections(
+ Layout* layout,
+ section_size_type group_size,
+ bool stubs_always_after_branch)
+{
+ // Group input sections and insert stub table
+ Layout::Section_list section_list;
+ layout->get_allocated_sections(§ion_list);
+ for (Layout::Section_list::const_iterator p = section_list.begin();
+ p != section_list.end();
+ ++p)
+ {
+ Arm_output_section<big_endian>* output_section =
+ Arm_output_section<big_endian>::as_arm_output_section(*p);
+ output_section->group_sections(group_size, stubs_always_after_branch,
+ this);
+ }
}
-// Return the size of a relocation while scanning during a relocatable
-// link.
+// Relaxation hook. This is where we do stub generation.
template<bool big_endian>
-unsigned int
-Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
- unsigned int r_type,
- Relobj* object)
+bool
+Target_arm<big_endian>::do_relax(
+ int pass,
+ const Input_objects* input_objects,
+ Symbol_table* symtab,
+ Layout* layout)
{
- r_type = get_real_reloc_type(r_type);
- switch (r_type)
+ // No need to generate stubs if this is a relocatable link.
+ gold_assert(!parameters->options().relocatable());
+
+ // If this is the first pass, we need to group input sections into
+ // stub groups.
+ bool done_exidx_fixup = false;
+ typedef typename Stub_table_list::iterator Stub_table_iterator;
+ if (pass == 1)
{
- case elfcpp::R_ARM_NONE:
- return 0;
+ // Determine the stub group size. The group size is the absolute
+ // value of the parameter --stub-group-size. If --stub-group-size
+ // is passed a negative value, we restict stubs to be always after
+ // the stubbed branches.
+ int32_t stub_group_size_param =
+ parameters->options().stub_group_size();
+ bool stubs_always_after_branch = stub_group_size_param < 0;
+ section_size_type stub_group_size = abs(stub_group_size_param);
+
+ if (stub_group_size == 1)
+ {
+ // Default value.
+ // Thumb branch range is +-4MB has to be used as the default
+ // maximum size (a given section can contain both ARM and Thumb
+ // code, so the worst case has to be taken into account). If we are
+ // fixing cortex-a8 errata, the branch range has to be even smaller,
+ // since wide conditional branch has a range of +-1MB only.
+ //
+ // This value is 48K less than that, which allows for 4096
+ // 12-byte stubs. If we exceed that, then we will fail to link.
+ // The user will have to relink with an explicit group size
+ // option.
+ stub_group_size = 4145152;
+ }
- case elfcpp::R_ARM_ABS8:
- return 1;
+ // The Cortex-A8 erratum fix depends on stubs not being in the same 4K
+ // page as the first half of a 32-bit branch straddling two 4K pages.
+ // This is a crude way of enforcing that. In addition, long conditional
+ // branches of THUMB-2 have a range of +-1M. If we are fixing cortex-A8
+ // erratum, limit the group size to (1M - 12k) to avoid unreachable
+ // cortex-A8 stubs from long conditional branches.
+ if (this->fix_cortex_a8_)
+ {
+ stubs_always_after_branch = true;
+ const section_size_type cortex_a8_group_size = 1024 * (1024 - 12);
+ stub_group_size = std::max(stub_group_size, cortex_a8_group_size);
+ }
- case elfcpp::R_ARM_ABS16:
- case elfcpp::R_ARM_THM_ABS5:
- return 2;
+ group_sections(layout, stub_group_size, stubs_always_after_branch);
+
+ // Also fix .ARM.exidx section coverage.
+ Arm_output_section<big_endian>* exidx_output_section = NULL;
+ for (Layout::Section_list::const_iterator p =
+ layout->section_list().begin();
+ p != layout->section_list().end();
+ ++p)
+ if ((*p)->type() == elfcpp::SHT_ARM_EXIDX)
+ {
+ if (exidx_output_section == NULL)
+ exidx_output_section =
+ Arm_output_section<big_endian>::as_arm_output_section(*p);
+ else
+ // We cannot handle this now.
+ gold_error(_("multiple SHT_ARM_EXIDX sections %s and %s in a "
+ "non-relocatable link"),
+ exidx_output_section->name(),
+ (*p)->name());
+ }
- case elfcpp::R_ARM_ABS32:
- case elfcpp::R_ARM_ABS32_NOI:
- case elfcpp::R_ARM_ABS12:
- case elfcpp::R_ARM_BASE_ABS:
- case elfcpp::R_ARM_REL32:
- case elfcpp::R_ARM_THM_CALL:
- case elfcpp::R_ARM_GOTOFF32:
- case elfcpp::R_ARM_BASE_PREL:
- case elfcpp::R_ARM_GOT_BREL:
- case elfcpp::R_ARM_GOT_PREL:
- case elfcpp::R_ARM_PLT32:
- case elfcpp::R_ARM_CALL:
- case elfcpp::R_ARM_JUMP24:
- case elfcpp::R_ARM_PREL31:
- case elfcpp::R_ARM_MOVW_ABS_NC:
- case elfcpp::R_ARM_MOVT_ABS:
- case elfcpp::R_ARM_THM_MOVW_ABS_NC:
- case elfcpp::R_ARM_THM_MOVT_ABS:
- case elfcpp::R_ARM_MOVW_PREL_NC:
- case elfcpp::R_ARM_MOVT_PREL:
- case elfcpp::R_ARM_THM_MOVW_PREL_NC:
- case elfcpp::R_ARM_THM_MOVT_PREL:
- return 4;
+ if (exidx_output_section != NULL)
+ {
+ this->fix_exidx_coverage(layout, input_objects, exidx_output_section,
+ symtab);
+ done_exidx_fixup = true;
+ }
+ }
+ else
+ {
+ // If this is not the first pass, addresses and file offsets have
+ // been reset at this point, set them here.
+ for (Stub_table_iterator sp = this->stub_tables_.begin();
+ sp != this->stub_tables_.end();
+ ++sp)
+ {
+ Arm_input_section<big_endian>* owner = (*sp)->owner();
+ off_t off = align_address(owner->original_size(),
+ (*sp)->addralign());
+ (*sp)->set_address_and_file_offset(owner->address() + off,
+ owner->offset() + off);
+ }
+ }
- case elfcpp::R_ARM_TARGET1:
- // This should have been mapped to another type already.
- // Fall through.
- case elfcpp::R_ARM_COPY:
- case elfcpp::R_ARM_GLOB_DAT:
- case elfcpp::R_ARM_JUMP_SLOT:
- case elfcpp::R_ARM_RELATIVE:
- // These are relocations which should only be seen by the
- // dynamic linker, and should never be seen here.
- gold_error(_("%s: unexpected reloc %u in object file"),
- object->name().c_str(), r_type);
- return 0;
+ // The Cortex-A8 stubs are sensitive to layout of code sections. At the
+ // beginning of each relaxation pass, just blow away all the stubs.
+ // Alternatively, we could selectively remove only the stubs and reloc
+ // information for code sections that have moved since the last pass.
+ // That would require more book-keeping.
+ if (this->fix_cortex_a8_)
+ {
+ // Clear all Cortex-A8 reloc information.
+ for (typename Cortex_a8_relocs_info::const_iterator p =
+ this->cortex_a8_relocs_info_.begin();
+ p != this->cortex_a8_relocs_info_.end();
+ ++p)
+ delete p->second;
+ this->cortex_a8_relocs_info_.clear();
+
+ // Remove all Cortex-A8 stubs.
+ for (Stub_table_iterator sp = this->stub_tables_.begin();
+ sp != this->stub_tables_.end();
+ ++sp)
+ (*sp)->remove_all_cortex_a8_stubs();
+ }
+
+ // Scan relocs for relocation stubs
+ for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
+ op != input_objects->relobj_end();
+ ++op)
+ {
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(*op);
+ arm_relobj->scan_sections_for_stubs(this, symtab, layout);
+ }
- default:
- object->error(_("unsupported reloc %u in object file"), r_type);
- return 0;
+ // Check all stub tables to see if any of them have their data sizes
+ // or addresses alignments changed. These are the only things that
+ // matter.
+ bool any_stub_table_changed = false;
+ Unordered_set<const Output_section*> sections_needing_adjustment;
+ for (Stub_table_iterator sp = this->stub_tables_.begin();
+ (sp != this->stub_tables_.end()) && !any_stub_table_changed;
+ ++sp)
+ {
+ if ((*sp)->update_data_size_and_addralign())
+ {
+ // Update data size of stub table owner.
+ Arm_input_section<big_endian>* owner = (*sp)->owner();
+ uint64_t address = owner->address();
+ off_t offset = owner->offset();
+ owner->reset_address_and_file_offset();
+ owner->set_address_and_file_offset(address, offset);
+
+ sections_needing_adjustment.insert(owner->output_section());
+ any_stub_table_changed = true;
+ }
}
-}
-// Scan the relocs during a relocatable link.
+ // Output_section_data::output_section() returns a const pointer but we
+ // need to update output sections, so we record all output sections needing
+ // update above and scan the sections here to find out what sections need
+ // to be updated.
+ for(Layout::Section_list::const_iterator p = layout->section_list().begin();
+ p != layout->section_list().end();
+ ++p)
+ {
+ if (sections_needing_adjustment.find(*p)
+ != sections_needing_adjustment.end())
+ (*p)->set_section_offsets_need_adjustment();
+ }
-template<bool big_endian>
-void
-Target_arm<big_endian>::scan_relocatable_relocs(
- const General_options& options,
- Symbol_table* symtab,
- Layout* layout,
- Sized_relobj<32, big_endian>* object,
- unsigned int data_shndx,
- unsigned int sh_type,
- const unsigned char* prelocs,
- size_t reloc_count,
- Output_section* output_section,
- bool needs_special_offset_handling,
- size_t local_symbol_count,
- const unsigned char* plocal_symbols,
- Relocatable_relocs* rr)
-{
- gold_assert(sh_type == elfcpp::SHT_REL);
+ // Stop relaxation if no EXIDX fix-up and no stub table change.
+ bool continue_relaxation = done_exidx_fixup || any_stub_table_changed;
- typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
- Relocatable_size_for_reloc> Scan_relocatable_relocs;
+ // Finalize the stubs in the last relaxation pass.
+ if (!continue_relaxation)
+ {
+ for (Stub_table_iterator sp = this->stub_tables_.begin();
+ (sp != this->stub_tables_.end()) && !any_stub_table_changed;
+ ++sp)
+ (*sp)->finalize_stubs();
+
+ // Update output local symbol counts of objects if necessary.
+ for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
+ op != input_objects->relobj_end();
+ ++op)
+ {
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(*op);
+
+ // Update output local symbol counts. We need to discard local
+ // symbols defined in parts of input sections that are discarded by
+ // relaxation.
+ if (arm_relobj->output_local_symbol_count_needs_update())
+ arm_relobj->update_output_local_symbol_count();
+ }
+ }
- gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
- Scan_relocatable_relocs>(
- options,
- symtab,
- layout,
- object,
- data_shndx,
- prelocs,
- reloc_count,
- output_section,
- needs_special_offset_handling,
- local_symbol_count,
- plocal_symbols,
- rr);
+ return continue_relaxation;
}
-// Relocate a section during a relocatable link.
+// Relocate a stub.
template<bool big_endian>
void
-Target_arm<big_endian>::relocate_for_relocatable(
+Target_arm<big_endian>::relocate_stub(
+ Stub* stub,
const Relocate_info<32, big_endian>* relinfo,
- unsigned int sh_type,
- const unsigned char* prelocs,
- size_t reloc_count,
Output_section* output_section,
- off_t offset_in_output_section,
- const Relocatable_relocs* rr,
unsigned char* view,
- elfcpp::Elf_types<32>::Elf_Addr view_address,
- section_size_type view_size,
- unsigned char* reloc_view,
- section_size_type reloc_view_size)
+ Arm_address address,
+ section_size_type view_size)
{
- gold_assert(sh_type == elfcpp::SHT_REL);
-
- gold::relocate_for_relocatable<32, big_endian, elfcpp::SHT_REL>(
- relinfo,
- prelocs,
- reloc_count,
- output_section,
- offset_in_output_section,
- rr,
- view,
- view_address,
- view_size,
- reloc_view,
- reloc_view_size);
+ Relocate relocate;
+ const Stub_template* stub_template = stub->stub_template();
+ for (size_t i = 0; i < stub_template->reloc_count(); i++)
+ {
+ size_t reloc_insn_index = stub_template->reloc_insn_index(i);
+ const Insn_template* insn = &stub_template->insns()[reloc_insn_index];
+
+ unsigned int r_type = insn->r_type();
+ section_size_type reloc_offset = stub_template->reloc_offset(i);
+ section_size_type reloc_size = insn->size();
+ gold_assert(reloc_offset + reloc_size <= view_size);
+
+ // This is the address of the stub destination.
+ Arm_address target = stub->reloc_target(i) + insn->reloc_addend();
+ Symbol_value<32> symval;
+ symval.set_output_value(target);
+
+ // Synthesize a fake reloc just in case. We don't have a symbol so
+ // we use 0.
+ unsigned char reloc_buffer[elfcpp::Elf_sizes<32>::rel_size];
+ memset(reloc_buffer, 0, sizeof(reloc_buffer));
+ elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer);
+ reloc_write.put_r_offset(reloc_offset);
+ reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type));
+ elfcpp::Rel<32, big_endian> rel(reloc_buffer);
+
+ relocate.relocate(relinfo, this, output_section,
+ this->fake_relnum_for_stubs, rel, r_type,
+ NULL, &symval, view + reloc_offset,
+ address + reloc_offset, reloc_size);
+ }
}
-// Return the value to use for a dynamic symbol which requires special
-// treatment. This is how we support equality comparisons of function
-// pointers across shared library boundaries, as described in the
-// processor specific ABI supplement.
+// Determine whether an object attribute tag takes an integer, a
+// string or both.
template<bool big_endian>
-uint64_t
-Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
+int
+Target_arm<big_endian>::do_attribute_arg_type(int tag) const
{
- gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
- return this->plt_section()->address() + gsym->plt_offset();
+ if (tag == Object_attribute::Tag_compatibility)
+ return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
+ | Object_attribute::ATTR_TYPE_FLAG_STR_VAL);
+ else if (tag == elfcpp::Tag_nodefaults)
+ return (Object_attribute::ATTR_TYPE_FLAG_INT_VAL
+ | Object_attribute::ATTR_TYPE_FLAG_NO_DEFAULT);
+ else if (tag == elfcpp::Tag_CPU_raw_name || tag == elfcpp::Tag_CPU_name)
+ return Object_attribute::ATTR_TYPE_FLAG_STR_VAL;
+ else if (tag < 32)
+ return Object_attribute::ATTR_TYPE_FLAG_INT_VAL;
+ else
+ return ((tag & 1) != 0
+ ? Object_attribute::ATTR_TYPE_FLAG_STR_VAL
+ : Object_attribute::ATTR_TYPE_FLAG_INT_VAL);
}
-// Map platform-specific relocs to real relocs
+// Reorder attributes.
//
+// The ABI defines that Tag_conformance should be emitted first, and that
+// Tag_nodefaults should be second (if either is defined). This sets those
+// two positions, and bumps up the position of all the remaining tags to
+// compensate.
+
template<bool big_endian>
-unsigned int
-Target_arm<big_endian>::get_real_reloc_type (unsigned int r_type)
+int
+Target_arm<big_endian>::do_attributes_order(int num) const
{
- switch (r_type)
+ // Reorder the known object attributes in output. We want to move
+ // Tag_conformance to position 4 and Tag_conformance to position 5
+ // and shift eveything between 4 .. Tag_conformance - 1 to make room.
+ if (num == 4)
+ return elfcpp::Tag_conformance;
+ if (num == 5)
+ return elfcpp::Tag_nodefaults;
+ if ((num - 2) < elfcpp::Tag_nodefaults)
+ return num - 2;
+ if ((num - 1) < elfcpp::Tag_conformance)
+ return num - 1;
+ return num;
+}
+
+// Scan a span of THUMB code for Cortex-A8 erratum.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::scan_span_for_cortex_a8_erratum(
+ Arm_relobj<big_endian>* arm_relobj,
+ unsigned int shndx,
+ section_size_type span_start,
+ section_size_type span_end,
+ const unsigned char* view,
+ Arm_address address)
+{
+ // Scan for 32-bit Thumb-2 branches which span two 4K regions, where:
+ //
+ // The opcode is BLX.W, BL.W, B.W, Bcc.W
+ // The branch target is in the same 4KB region as the
+ // first half of the branch.
+ // The instruction before the branch is a 32-bit
+ // length non-branch instruction.
+ section_size_type i = span_start;
+ bool last_was_32bit = false;
+ bool last_was_branch = false;
+ while (i < span_end)
{
- case elfcpp::R_ARM_TARGET1:
- // This is either R_ARM_ABS32 or R_ARM_REL32;
- return elfcpp::R_ARM_ABS32;
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ const Valtype* wv = reinterpret_cast<const Valtype*>(view + i);
+ uint32_t insn = elfcpp::Swap<16, big_endian>::readval(wv);
+ bool is_blx = false, is_b = false;
+ bool is_bl = false, is_bcc = false;
+
+ bool insn_32bit = (insn & 0xe000) == 0xe000 && (insn & 0x1800) != 0x0000;
+ if (insn_32bit)
+ {
+ // Load the rest of the insn (in manual-friendly order).
+ insn = (insn << 16) | elfcpp::Swap<16, big_endian>::readval(wv + 1);
+
+ // Encoding T4: B<c>.W.
+ is_b = (insn & 0xf800d000U) == 0xf0009000U;
+ // Encoding T1: BL<c>.W.
+ is_bl = (insn & 0xf800d000U) == 0xf000d000U;
+ // Encoding T2: BLX<c>.W.
+ is_blx = (insn & 0xf800d000U) == 0xf000c000U;
+ // Encoding T3: B<c>.W (not permitted in IT block).
+ is_bcc = ((insn & 0xf800d000U) == 0xf0008000U
+ && (insn & 0x07f00000U) != 0x03800000U);
+ }
- case elfcpp::R_ARM_TARGET2:
- // This can be any reloc type but ususally is R_ARM_GOT_PREL
- return elfcpp::R_ARM_GOT_PREL;
+ bool is_32bit_branch = is_b || is_bl || is_blx || is_bcc;
+
+ // If this instruction is a 32-bit THUMB branch that crosses a 4K
+ // page boundary and it follows 32-bit non-branch instruction,
+ // we need to work around.
+ if (is_32bit_branch
+ && ((address + i) & 0xfffU) == 0xffeU
+ && last_was_32bit
+ && !last_was_branch)
+ {
+ // Check to see if there is a relocation stub for this branch.
+ bool force_target_arm = false;
+ bool force_target_thumb = false;
+ const Cortex_a8_reloc* cortex_a8_reloc = NULL;
+ Cortex_a8_relocs_info::const_iterator p =
+ this->cortex_a8_relocs_info_.find(address + i);
+
+ if (p != this->cortex_a8_relocs_info_.end())
+ {
+ cortex_a8_reloc = p->second;
+ bool target_is_thumb = (cortex_a8_reloc->destination() & 1) != 0;
+
+ if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
+ && !target_is_thumb)
+ force_target_arm = true;
+ else if (cortex_a8_reloc->r_type() == elfcpp::R_ARM_THM_CALL
+ && target_is_thumb)
+ force_target_thumb = true;
+ }
- default:
- return r_type;
+ off_t offset;
+ Stub_type stub_type = arm_stub_none;
+
+ // Check if we have an offending branch instruction.
+ uint16_t upper_insn = (insn >> 16) & 0xffffU;
+ uint16_t lower_insn = insn & 0xffffU;
+ typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
+
+ if (cortex_a8_reloc != NULL
+ && cortex_a8_reloc->reloc_stub() != NULL)
+ // We've already made a stub for this instruction, e.g.
+ // it's a long branch or a Thumb->ARM stub. Assume that
+ // stub will suffice to work around the A8 erratum (see
+ // setting of always_after_branch above).
+ ;
+ else if (is_bcc)
+ {
+ offset = RelocFuncs::thumb32_cond_branch_offset(upper_insn,
+ lower_insn);
+ stub_type = arm_stub_a8_veneer_b_cond;
+ }
+ else if (is_b || is_bl || is_blx)
+ {
+ offset = RelocFuncs::thumb32_branch_offset(upper_insn,
+ lower_insn);
+ if (is_blx)
+ offset &= ~3;
+
+ stub_type = (is_blx
+ ? arm_stub_a8_veneer_blx
+ : (is_bl
+ ? arm_stub_a8_veneer_bl
+ : arm_stub_a8_veneer_b));
+ }
+
+ if (stub_type != arm_stub_none)
+ {
+ Arm_address pc_for_insn = address + i + 4;
+
+ // The original instruction is a BL, but the target is
+ // an ARM instruction. If we were not making a stub,
+ // the BL would have been converted to a BLX. Use the
+ // BLX stub instead in that case.
+ if (this->may_use_blx() && force_target_arm
+ && stub_type == arm_stub_a8_veneer_bl)
+ {
+ stub_type = arm_stub_a8_veneer_blx;
+ is_blx = true;
+ is_bl = false;
+ }
+ // Conversely, if the original instruction was
+ // BLX but the target is Thumb mode, use the BL stub.
+ else if (force_target_thumb
+ && stub_type == arm_stub_a8_veneer_blx)
+ {
+ stub_type = arm_stub_a8_veneer_bl;
+ is_blx = false;
+ is_bl = true;
+ }
+
+ if (is_blx)
+ pc_for_insn &= ~3;
+
+ // If we found a relocation, use the proper destination,
+ // not the offset in the (unrelocated) instruction.
+ // Note this is always done if we switched the stub type above.
+ if (cortex_a8_reloc != NULL)
+ offset = (off_t) (cortex_a8_reloc->destination() - pc_for_insn);
+
+ Arm_address target = (pc_for_insn + offset) | (is_blx ? 0 : 1);
+
+ // Add a new stub if destination address in in the same page.
+ if (((address + i) & ~0xfffU) == (target & ~0xfffU))
+ {
+ Cortex_a8_stub* stub =
+ this->stub_factory_.make_cortex_a8_stub(stub_type,
+ arm_relobj, shndx,
+ address + i,
+ target, insn);
+ Stub_table<big_endian>* stub_table =
+ arm_relobj->stub_table(shndx);
+ gold_assert(stub_table != NULL);
+ stub_table->add_cortex_a8_stub(address + i, stub);
+ }
+ }
+ }
+
+ i += insn_32bit ? 4 : 2;
+ last_was_32bit = insn_32bit;
+ last_was_branch = is_32bit_branch;
}
}
-// The selector for arm object files.
+// Apply the Cortex-A8 workaround.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::apply_cortex_a8_workaround(
+ const Cortex_a8_stub* stub,
+ Arm_address stub_address,
+ unsigned char* insn_view,
+ Arm_address insn_address)
+{
+ typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(insn_view);
+ Valtype upper_insn = elfcpp::Swap<16, big_endian>::readval(wv);
+ Valtype lower_insn = elfcpp::Swap<16, big_endian>::readval(wv + 1);
+ off_t branch_offset = stub_address - (insn_address + 4);
+
+ typedef struct Arm_relocate_functions<big_endian> RelocFuncs;
+ switch (stub->stub_template()->type())
+ {
+ case arm_stub_a8_veneer_b_cond:
+ // For a conditional branch, we re-write it to be a uncondition
+ // branch to the stub. We use the THUMB-2 encoding here.
+ upper_insn = 0xf000U;
+ lower_insn = 0xb800U;
+ // Fall through
+ case arm_stub_a8_veneer_b:
+ case arm_stub_a8_veneer_bl:
+ case arm_stub_a8_veneer_blx:
+ if ((lower_insn & 0x5000U) == 0x4000U)
+ // For a BLX instruction, make sure that the relocation is
+ // rounded up to a word boundary. This follows the semantics of
+ // the instruction which specifies that bit 1 of the target
+ // address will come from bit 1 of the base address.
+ branch_offset = (branch_offset + 2) & ~3;
+
+ // Put BRANCH_OFFSET back into the insn.
+ gold_assert(!utils::has_overflow<25>(branch_offset));
+ upper_insn = RelocFuncs::thumb32_branch_upper(upper_insn, branch_offset);
+ lower_insn = RelocFuncs::thumb32_branch_lower(lower_insn, branch_offset);
+ break;
+
+ default:
+ gold_unreachable();
+ }
+
+ // Put the relocated value back in the object file:
+ elfcpp::Swap<16, big_endian>::writeval(wv, upper_insn);
+ elfcpp::Swap<16, big_endian>::writeval(wv + 1, lower_insn);
+}
template<bool big_endian>
class Target_selector_arm : public Target_selector
{ return new Target_arm<big_endian>(); }
};
+// Fix .ARM.exidx section coverage.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::fix_exidx_coverage(
+ Layout* layout,
+ const Input_objects* input_objects,
+ Arm_output_section<big_endian>* exidx_section,
+ Symbol_table* symtab)
+{
+ // We need to look at all the input sections in output in ascending
+ // order of of output address. We do that by building a sorted list
+ // of output sections by addresses. Then we looks at the output sections
+ // in order. The input sections in an output section are already sorted
+ // by addresses within the output section.
+
+ typedef std::set<Output_section*, output_section_address_less_than>
+ Sorted_output_section_list;
+ Sorted_output_section_list sorted_output_sections;
+
+ // Find out all the output sections of input sections pointed by
+ // EXIDX input sections.
+ for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
+ p != input_objects->relobj_end();
+ ++p)
+ {
+ Arm_relobj<big_endian>* arm_relobj =
+ Arm_relobj<big_endian>::as_arm_relobj(*p);
+ std::vector<unsigned int> shndx_list;
+ arm_relobj->get_exidx_shndx_list(&shndx_list);
+ for (size_t i = 0; i < shndx_list.size(); ++i)
+ {
+ const Arm_exidx_input_section* exidx_input_section =
+ arm_relobj->exidx_input_section_by_shndx(shndx_list[i]);
+ gold_assert(exidx_input_section != NULL);
+ if (!exidx_input_section->has_errors())
+ {
+ unsigned int text_shndx = exidx_input_section->link();
+ Output_section *os = arm_relobj->output_section(text_shndx);
+ if (os != NULL && (os->flags() & elfcpp::SHF_ALLOC) != 0)
+ sorted_output_sections.insert(os);
+ }
+ }
+ }
+
+ // Go over the output sections in ascending order of output addresses.
+ typedef typename Arm_output_section<big_endian>::Text_section_list
+ Text_section_list;
+ Text_section_list sorted_text_sections;
+ for(typename Sorted_output_section_list::iterator p =
+ sorted_output_sections.begin();
+ p != sorted_output_sections.end();
+ ++p)
+ {
+ Arm_output_section<big_endian>* arm_output_section =
+ Arm_output_section<big_endian>::as_arm_output_section(*p);
+ arm_output_section->append_text_sections_to_list(&sorted_text_sections);
+ }
+
+ exidx_section->fix_exidx_coverage(layout, sorted_text_sections, symtab,
+ merge_exidx_entries());
+}
+
Target_selector_arm<false> target_selector_arm;
Target_selector_arm<true> target_selector_armbe;