// arm.cc -- arm target support for gold.
-// Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+// Copyright 2009, 2010, 2011, 2012 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
}
};
-// Utilities for manipulating integers of up to 32-bits
-
-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>
{
{
// 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));
+ return Bits<16>::sign_extend32(((val >> 4) & 0xf000) | (val & 0xfff));
}
// Insert X into VAL based on the ARM instruction encoding described
{
// 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));
+ return Bits<16>::sign_extend32(((val >> 4) & 0xf000)
+ | ((val >> 15) & 0x0800)
+ | ((val >> 4) & 0x0700)
+ | (val & 0x00ff));
}
// Insert X into VAL based on the Thumb2 instruction encoding
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));
+ return Bits<25>::sign_extend32((s << 24) | (i1 << 23) | (i2 << 22)
+ | (upper << 12) | (lower << 1));
}
// Insert OFFSET to a 32-bit THUMB branch and return the upper instruction.
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));
+ return Bits<21>::sign_extend32((upper << 12) | (lower << 1));
}
// Insert OFFSET to a 32-bit THUMB conditional branch and return the upper
typedef typename elfcpp::Swap<8, big_endian>::Valtype Valtype;
Valtype* wv = reinterpret_cast<Valtype*>(view);
Valtype val = elfcpp::Swap<8, big_endian>::readval(wv);
- int32_t addend = utils::sign_extend<8>(val);
+ int32_t addend = Bits<8>::sign_extend32(val);
Arm_address x = psymval->value(object, addend);
- val = utils::bit_select(val, x, 0xffU);
+ val = Bits<32>::bit_select32(val, x, 0xffU);
elfcpp::Swap<8, big_endian>::writeval(wv, val);
// R_ARM_ABS8 permits signed or unsigned results.
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);
+ val = Bits<32>::bit_select32(val, x << 6, 0x7e0U);
elfcpp::Swap<16, big_endian>::writeval(wv, val);
// R_ARM_ABS16 permits signed or unsigned results.
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);
+ val = Bits<32>::bit_select32(val, x, 0x0fffU);
elfcpp::Swap<32, big_endian>::writeval(wv, val);
- return (utils::has_overflow<12>(x)
+ return (Bits<12>::has_overflow32(x)
? This::STATUS_OVERFLOW
: This::STATUS_OKAY);
}
typedef typename elfcpp::Swap_unaligned<16, big_endian>::Valtype Valtype;
typedef typename elfcpp::Swap<32, big_endian>::Valtype Reltype;
Valtype val = elfcpp::Swap_unaligned<16, big_endian>::readval(view);
- int32_t addend = utils::sign_extend<16>(val);
+ int32_t addend = Bits<16>::sign_extend32(val);
Arm_address x = psymval->value(object, addend);
- val = utils::bit_select(val, x, 0xffffU);
+ val = Bits<32>::bit_select32(val, x, 0xffffU);
elfcpp::Swap_unaligned<16, big_endian>::writeval(view, val);
// R_ARM_ABS16 permits signed or unsigned results.
typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
Valtype* wv = reinterpret_cast<Valtype*>(view);
Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
- int32_t addend = utils::sign_extend<8>((val & 0x00ff) << 1);
+ int32_t addend = Bits<8>::sign_extend32((val & 0x00ff) << 1);
int32_t x = (psymval->value(object, addend) - address);
elfcpp::Swap<16, big_endian>::writeval(wv, ((val & 0xff00)
| ((x & 0x01fe) >> 1)));
// We do a 9-bit overflow check because x is right-shifted by 1 bit.
- return (utils::has_overflow<9>(x)
+ return (Bits<9>::has_overflow32(x)
? This::STATUS_OVERFLOW
: This::STATUS_OKAY);
}
typedef typename elfcpp::Swap<16, big_endian>::Valtype Valtype;
Valtype* wv = reinterpret_cast<Valtype*>(view);
Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
- int32_t addend = utils::sign_extend<11>((val & 0x07ff) << 1);
+ int32_t addend = Bits<11>::sign_extend32((val & 0x07ff) << 1);
int32_t x = (psymval->value(object, addend) - address);
elfcpp::Swap<16, big_endian>::writeval(wv, ((val & 0xf800)
| ((x & 0x0ffe) >> 1)));
// We do a 12-bit overflow check because x is right-shifted by 1 bit.
- return (utils::has_overflow<12>(x)
+ return (Bits<12>::has_overflow32(x)
? This::STATUS_OVERFLOW
: This::STATUS_OKAY);
}
{
typedef typename elfcpp::Swap_unaligned<32, big_endian>::Valtype Valtype;
Valtype val = elfcpp::Swap_unaligned<32, big_endian>::readval(view);
- Valtype addend = utils::sign_extend<31>(val);
+ Valtype addend = Bits<31>::sign_extend32(val);
Valtype x = (psymval->value(object, addend) | thumb_bit) - address;
- val = utils::bit_select(val, x, 0x7fffffffU);
+ val = Bits<32>::bit_select32(val, x, 0x7fffffffU);
elfcpp::Swap_unaligned<32, big_endian>::writeval(view, val);
- return (utils::has_overflow<31>(x) ?
- This::STATUS_OVERFLOW : This::STATUS_OKAY);
+ return (Bits<31>::has_overflow32(x)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
}
// R_ARM_MOVW_ABS_NC: (S + A) | T (relative address base is )
- 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))
+ return ((check_overflow && Bits<16>::has_overflow32(x))
? This::STATUS_OVERFLOW
: This::STATUS_OKAY);
}
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))
+ return ((check_overflow && Bits<16>::has_overflow32(x))
? This::STATUS_OVERFLOW
: This::STATUS_OKAY);
}
return This::STATUS_OKAY;
}
- Valtype addend = utils::sign_extend<26>(val << 2);
+ Valtype addend = Bits<26>::sign_extend32(val << 2);
Valtype branch_target = psymval->value(object, addend);
int32_t branch_offset = branch_target - address;
Reloc_stub* stub = NULL;
if (!parameters->options().relocatable()
- && (utils::has_overflow<26>(branch_offset)
+ && (Bits<26>::has_overflow32(branch_offset)
|| ((thumb_bit != 0)
&& !(may_use_blx && r_type == elfcpp::R_ARM_CALL))))
{
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));
+ gold_assert(!Bits<26>::has_overflow32(branch_offset));
}
}
val = (val & 0xffffff) | 0xfa000000 | ((branch_offset & 2) << 23);
}
- val = utils::bit_select(val, (branch_offset >> 2), 0xffffffUL);
+ val = Bits<32>::bit_select32(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);
+ return (Bits<26>::has_overflow32(branch_offset)
+ ? This::STATUS_OVERFLOW
+ : This::STATUS_OKAY);
}
// Relocate THUMB long branches. This handles relocation types
// For BLX, bit 1 of target address comes from bit 1 of base address.
bool may_use_blx = arm_target->may_use_v5t_interworking();
if (thumb_bit == 0 && may_use_blx)
- branch_target = utils::bit_select(branch_target, address, 0x2);
+ branch_target = Bits<32>::bit_select32(branch_target, address, 0x2);
int32_t branch_offset = branch_target - address;
// 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))
+ && ((!thumb2 && Bits<23>::has_overflow32(branch_offset))
+ || (thumb2 && Bits<25>::has_overflow32(branch_offset))
|| ((thumb_bit == 0)
&& (((r_type == elfcpp::R_ARM_THM_CALL) && !may_use_blx)
|| r_type == elfcpp::R_ARM_THM_JUMP24))))
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_target = Bits<32>::bit_select32(branch_target, address, 0x2);
branch_offset = branch_target - address;
}
}
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));
+ gold_assert(!Bits<25>::has_overflow32(branch_offset));
return ((thumb2
- ? utils::has_overflow<25>(branch_offset)
- : utils::has_overflow<23>(branch_offset))
+ ? Bits<25>::has_overflow32(branch_offset)
+ : Bits<23>::has_overflow32(branch_offset))
? This::STATUS_OVERFLOW
: This::STATUS_OKAY);
}
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)
+ return (Bits<21>::has_overflow32(branch_offset)
? This::STATUS_OVERFLOW
: This::STATUS_OKAY);
}
// 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);
+ destination = Bits<32>::bit_select32(destination, location, 0x2);
branch_offset = static_cast<int64_t>(destination) - location;
// Handle cases where:
// 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))
+ if (Bits<31>::has_overflow32(offset))
gold_error(_("PREL31 overflow in EXIDX_CANTUNWIND entry"));
elfcpp::Swap_unaligned<32, big_endian>::writeval(oview,
prel31_offset & 0x7fffffffU);
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);
+ return Bits<26>::sign_extend32(val << 2);
}
case elfcpp::R_ARM_THM_CALL:
branch_offset = (branch_offset + 2) & ~3;
// Put BRANCH_OFFSET back into the insn.
- gold_assert(!utils::has_overflow<25>(branch_offset));
+ gold_assert(!Bits<25>::has_overflow32(branch_offset));
upper_insn = RelocFuncs::thumb32_branch_upper(upper_insn, branch_offset);
lower_insn = RelocFuncs::thumb32_branch_lower(lower_insn, branch_offset);
break;
// reloc.h -- relocate input files for gold -*- C++ -*-
-// Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+// Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012
+// Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
{ This::template pcrela<64>(view, object, psymval, addend, address); }
};
+// Integer manipulation functions used by various targets when
+// performing relocations.
+
+template<int bits>
+class Bits
+{
+ public:
+ // Sign extend an n-bit unsigned integer stored in a uint32_t into
+ // an int32_t. BITS must be between 0 and 32.
+ static inline int32_t
+ sign_extend32(uint32_t val)
+ {
+ gold_assert(bits >= 0 && bits <= 32);
+ if (bits == 32)
+ return static_cast<int32_t>(val);
+ uint32_t mask = (~static_cast<uint32_t>(0)) >> (32 - bits);
+ val &= mask;
+ uint32_t top_bit = 1U << (bits - 1);
+ int32_t as_signed = static_cast<int32_t>(val);
+ if ((val & top_bit) != 0)
+ as_signed -= static_cast<int32_t>(top_bit * 2);
+ return as_signed;
+ }
+
+ // Return true if VAL (stored in a uint32_t) has overflowed a signed
+ // value with BITS bits.
+ static inline bool
+ has_overflow32(uint32_t val)
+ {
+ gold_assert(bits >= 0 && bits <= 32);
+ if (bits == 32)
+ return false;
+ int32_t max = (1 << (bits - 1)) - 1;
+ int32_t min = -(1 << (bits - 1));
+ int32_t as_signed = static_cast<int32_t>(val);
+ return as_signed > max || as_signed < min;
+ }
+
+ // Return true if VAL (stored in a uint32_t) has overflowed both a
+ // signed and an unsigned value. E.g.,
+ // Bits<8>::has_signed_unsigned_overflow32 would check -128 <= VAL <
+ // 255.
+ static inline bool
+ has_signed_unsigned_overflow32(uint32_t val)
+ {
+ gold_assert(bits >= 0 && bits <= 32);
+ if (bits == 32)
+ return false;
+ int32_t max = static_cast<int32_t>((1U << bits) - 1);
+ int32_t min = -(1 << (bits - 1));
+ int32_t as_signed = static_cast<int32_t>(val);
+ 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_select32(uint32_t a, uint32_t b, uint32_t mask)
+ { return (a & ~mask) | (b & mask); }
+
+ // Sign extend an n-bit unsigned integer stored in a uint64_t into
+ // an int64_t. BITS must be between 0 and 64.
+ static inline int64_t
+ sign_extend(uint64_t val)
+ {
+ gold_assert(bits >= 0 && bits <= 64);
+ if (bits == 64)
+ return static_cast<int64_t>(val);
+ uint64_t mask = (~static_cast<uint64_t>(0)) >> (64 - bits);
+ val &= mask;
+ uint64_t top_bit = static_cast<uint64_t>(1) << (bits - 1);
+ int64_t as_signed = static_cast<int64_t>(val);
+ if ((val & top_bit) != 0)
+ as_signed -= static_cast<int64_t>(top_bit * 2);
+ return as_signed;
+ }
+
+ // Return true if VAL (stored in a uint64_t) has overflowed a signed
+ // value with BITS bits.
+ static inline bool
+ has_overflow(uint64_t val)
+ {
+ gold_assert(bits >= 0 && bits <= 64);
+ if (bits == 64)
+ return false;
+ int64_t max = (static_cast<int64_t>(1) << (bits - 1)) - 1;
+ int64_t min = -(static_cast<int64_t>(1) << (bits - 1));
+ int64_t as_signed = static_cast<int64_t>(val);
+ return as_signed > max || as_signed < min;
+ }
+
+ // Return true if VAL (stored in a uint64_t) has overflowed both a
+ // signed and an unsigned value. E.g.,
+ // Bits<8>::has_signed_unsigned_overflow would check -128 <= VAL <
+ // 255.
+ static inline bool
+ has_signed_unsigned_overflow64(uint64_t val)
+ {
+ gold_assert(bits >= 0 && bits <= 64);
+ if (bits == 64)
+ return false;
+ int64_t max = static_cast<int64_t>((static_cast<uint64_t>(1) << bits) - 1);
+ int64_t min = -(static_cast<int64_t>(1) << (bits - 1));
+ int64_t as_signed = static_cast<int64_t>(val);
+ 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 uint64_t
+ bit_select64(uint64_t a, uint64_t b, uint64_t mask)
+ { return (a & ~mask) | (b & mask); }
+};
+
// Track relocations while reading a section. This lets you ask for
// the relocation at a certain offset, and see how relocs occur
// between points of interest.