From 2e30d253b71680ea2f09203ad412f0eb7d3f7ff3 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Mon, 1 Oct 2007 21:30:59 +0000 Subject: [PATCH] From Craig Silverstein: x86_64 support. --- gold/Makefile.am | 4 +- gold/Makefile.in | 5 +- gold/po/POTFILES.in | 1 + gold/po/gold.pot | 88 +-- gold/x86_64.cc | 1619 +++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 1670 insertions(+), 47 deletions(-) create mode 100644 gold/x86_64.cc diff --git a/gold/Makefile.am b/gold/Makefile.am index e4764757f73..bb5d3f6cc57 100644 --- a/gold/Makefile.am +++ b/gold/Makefile.am @@ -79,10 +79,10 @@ YFILES = \ EXTRA_DIST = yyscript.c yyscript.h TARGETSOURCES = \ - i386.cc + i386.cc x86_64.cc ALL_TARGETOBJS = \ - i386.$(OBJEXT) + i386.$(OBJEXT) x86_64.$(OBJEXT) libgold_a_SOURCES = $(CCFILES) $(HFILES) $(YFILES) diff --git a/gold/Makefile.in b/gold/Makefile.in index 3ca6b8cd581..5db510ed161 100644 --- a/gold/Makefile.in +++ b/gold/Makefile.in @@ -325,10 +325,10 @@ YFILES = \ EXTRA_DIST = yyscript.c yyscript.h TARGETSOURCES = \ - i386.cc + i386.cc x86_64.cc ALL_TARGETOBJS = \ - i386.$(OBJEXT) + i386.$(OBJEXT) x86_64.$(OBJEXT) libgold_a_SOURCES = $(CCFILES) $(HFILES) $(YFILES) sources_var = main.cc @@ -465,6 +465,7 @@ distclean-compile: @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/symtab.Po@am__quote@ @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/target-select.Po@am__quote@ @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/workqueue.Po@am__quote@ +@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/x86_64.Po@am__quote@ @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/yyscript.Po@am__quote@ .c.o: diff --git a/gold/po/POTFILES.in b/gold/po/POTFILES.in index c41e6173d1a..8c529d570f2 100644 --- a/gold/po/POTFILES.in +++ b/gold/po/POTFILES.in @@ -48,3 +48,4 @@ target-select.cc target-select.h workqueue.cc workqueue.h +x86_64.cc diff --git a/gold/po/gold.pot b/gold/po/gold.pot index e2caf15596c..208c6b35b5c 100644 --- a/gold/po/gold.pot +++ b/gold/po/gold.pot @@ -8,7 +8,7 @@ msgid "" msgstr "" "Project-Id-Version: PACKAGE VERSION\n" "Report-Msgid-Bugs-To: \n" -"POT-Creation-Date: 2007-09-25 22:42-0700\n" +"POT-Creation-Date: 2007-10-01 14:30-0700\n" "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n" "Last-Translator: FULL NAME \n" "Language-Team: LANGUAGE \n" @@ -171,7 +171,7 @@ msgstr "" msgid "%s: %s: size of dynamic symbols is not multiple of symbol size\n" msgstr "" -#: dynobj.cc:1266 +#: dynobj.cc:1302 #, c-format msgid "%s: symbol %s has undefined version %s\n" msgstr "" @@ -265,22 +265,23 @@ msgid "pthread_cond_signal failed" msgstr "" #. FIXME: This needs to specify the location somehow. -#: i386.cc:130 +#: i386.cc:130 x86_64.cc:137 #, c-format msgid "%s: missing expected TLS relocation\n" msgstr "" -#: i386.cc:751 i386.cc:912 i386.cc:1174 +#: i386.cc:751 i386.cc:912 i386.cc:1174 x86_64.cc:733 x86_64.cc:886 +#: x86_64.cc:1169 #, c-format msgid "%s: %s: unexpected reloc %u in object file\n" msgstr "" -#: i386.cc:788 i386.cc:808 +#: i386.cc:788 i386.cc:808 x86_64.cc:767 x86_64.cc:788 #, c-format msgid "%s: %s: unsupported reloc %u against local symbol\n" msgstr "" -#: i386.cc:948 i386.cc:969 +#: i386.cc:948 i386.cc:969 x86_64.cc:920 x86_64.cc:942 #, c-format msgid "%s: %s: unsupported reloc %u against global symbol %s\n" msgstr "" @@ -290,32 +291,33 @@ msgstr "" msgid "%s: %s: unsupported RELA reloc section\n" msgstr "" -#: i386.cc:1082 +#: i386.cc:1082 x86_64.cc:1055 #, c-format msgid "%s: %s: missing expected TLS relocation\n" msgstr "" -#: i386.cc:1206 i386.cc:1283 i386.cc:1294 +#: i386.cc:1206 i386.cc:1283 i386.cc:1294 x86_64.cc:1203 x86_64.cc:1281 +#: x86_64.cc:1290 #, c-format msgid "%s: %s: unsupported reloc %u\n" msgstr "" -#: i386.cc:1233 +#: i386.cc:1233 x86_64.cc:1231 #, c-format msgid "%s: %s: TLS reloc but no TLS segment\n" msgstr "" -#: i386.cc:1268 +#: i386.cc:1268 x86_64.cc:1266 #, c-format msgid "%s: %s: unsupported reloc type %u\n" msgstr "" -#: i386.cc:1477 +#: i386.cc:1477 x86_64.cc:1478 #, c-format msgid "%s: %s: TLS relocation out of range\n" msgstr "" -#: i386.cc:1495 +#: i386.cc:1495 x86_64.cc:1496 #, c-format msgid "%s: %s: TLS relocation against invalid instruction\n" msgstr "" @@ -386,62 +388,62 @@ msgstr "" msgid "%s: %s: local symbol %u section name out of range: %u >= %u\n" msgstr "" -#: object.cc:857 +#: object.cc:860 #, c-format msgid "%s: %s: unsupported ELF file type %d\n" msgstr "" -#: object.cc:876 object.cc:929 object.cc:964 +#: object.cc:879 object.cc:932 object.cc:967 #, c-format msgid "%s: %s: ELF file too short\n" msgstr "" -#: object.cc:885 +#: object.cc:888 #, c-format msgid "%s: %s: invalid ELF version 0\n" msgstr "" -#: object.cc:888 +#: object.cc:891 #, c-format msgid "%s: %s: unsupported ELF version %d\n" msgstr "" -#: object.cc:896 +#: object.cc:899 #, c-format msgid "%s: %s: invalid ELF class 0\n" msgstr "" -#: object.cc:903 +#: object.cc:906 #, c-format msgid "%s: %s: unsupported ELF class %d\n" msgstr "" -#: object.cc:911 +#: object.cc:914 #, c-format msgid "%s: %s: invalid ELF data encoding\n" msgstr "" -#: object.cc:918 +#: object.cc:921 #, c-format msgid "%s: %s: unsupported ELF data encoding %d\n" msgstr "" -#: object.cc:941 +#: object.cc:944 #, c-format msgid "%s: %s: not configured to support 32-bit big-endian object\n" msgstr "" -#: object.cc:954 +#: object.cc:957 #, c-format msgid "%s: %s: not configured to support 32-bit little-endian object\n" msgstr "" -#: object.cc:976 +#: object.cc:979 #, c-format msgid "%s: %s: not configured to support 64-bit big-endian object\n" msgstr "" -#: object.cc:989 +#: object.cc:992 #, c-format msgid "%s: %s: not configured to support 64-bit little-endian object\n" msgstr "" @@ -597,37 +599,37 @@ msgstr "" msgid "%s: -%c: %s\n" msgstr "" -#: output.cc:922 +#: output.cc:1011 #, c-format msgid "%s: %s: invalid alignment %lu for section \"%s\"\n" msgstr "" -#: output.cc:1571 +#: output.cc:1660 #, c-format msgid "%s: %s: open: %s\n" msgstr "" -#: output.cc:1580 +#: output.cc:1669 #, c-format msgid "%s: %s: lseek: %s\n" msgstr "" -#: output.cc:1587 +#: output.cc:1676 #, c-format msgid "%s: %s: write: %s\n" msgstr "" -#: output.cc:1597 +#: output.cc:1686 #, c-format msgid "%s: %s: mmap: %s\n" msgstr "" -#: output.cc:1611 +#: output.cc:1700 #, c-format msgid "%s: %s: munmap: %s\n" msgstr "" -#: output.cc:1619 +#: output.cc:1708 #, c-format msgid "%s: %s: close: %s\n" msgstr "" @@ -678,42 +680,37 @@ msgstr "" msgid "%s: %s: unsupported symbol binding %d for symbol %s\n" msgstr "" -#: symtab.cc:476 symtab.cc:573 -#, c-format -msgid "%s: %s: mixing 32-bit and 64-bit ELF objects\n" -msgstr "" - -#: symtab.cc:493 +#: symtab.cc:518 #, c-format msgid "%s: %s: bad global symbol name offset %u at %lu\n" msgstr "" -#: symtab.cc:580 +#: symtab.cc:597 #, c-format msgid "%s: %s: too few symbol versions\n" msgstr "" -#: symtab.cc:600 +#: symtab.cc:617 #, c-format msgid "%s: %s: bad symbol name offset %u at %lu\n" msgstr "" -#: symtab.cc:653 +#: symtab.cc:670 #, c-format msgid "%s: %s: versym for symbol %zu out of range: %u\n" msgstr "" -#: symtab.cc:661 +#: symtab.cc:678 #, c-format msgid "%s: %s: versym for symbol %zu has no name: %u\n" msgstr "" -#: symtab.cc:1200 symtab.cc:1373 +#: symtab.cc:1248 symtab.cc:1445 #, c-format msgid "%s: %s: unsupported symbol section 0x%x\n" msgstr "" -#: symtab.cc:1570 +#: symtab.cc:1665 #, c-format msgid "%s: %s: warning: %s\n" msgstr "" @@ -727,3 +724,8 @@ msgstr "" #, c-format msgid "%s: %s: undefined reference to '%s'\n" msgstr "" + +#: x86_64.cc:965 +#, c-format +msgid "%s: %s: unsupported REL reloc section\n" +msgstr "" diff --git a/gold/x86_64.cc b/gold/x86_64.cc new file mode 100644 index 00000000000..e2ad4bb8e7c --- /dev/null +++ b/gold/x86_64.cc @@ -0,0 +1,1619 @@ +// x86_64.cc -- x86_64 target support for gold. + +// Copyright 2006, 2007, Free Software Foundation, Inc. +// Written by Ian Lance Taylor . + +// This file is part of gold. + +// This program is free software; you can redistribute it and/or +// modify it under the terms of the GNU Library General Public License +// as published by the Free Software Foundation; either version 2, or +// (at your option) any later version. + +// In addition to the permissions in the GNU Library General Public +// License, the Free Software Foundation gives you unlimited +// permission to link the compiled version of this file into +// combinations with other programs, and to distribute those +// combinations without any restriction coming from the use of this +// file. (The Library Public License restrictions do apply in other +// respects; for example, they cover modification of the file, and +/// distribution when not linked into a combined executable.) + +// This program is distributed in the hope that it will be useful, but +// WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Library General Public License for more details. + +// You should have received a copy of the GNU Library General Public +// License along with this program; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA +// 02110-1301, USA. + +#include "gold.h" + +#include + +#include "elfcpp.h" +#include "parameters.h" +#include "reloc.h" +#include "x86_64.h" +#include "object.h" +#include "symtab.h" +#include "layout.h" +#include "output.h" +#include "target.h" +#include "target-reloc.h" +#include "target-select.h" + +namespace +{ + +using namespace gold; + +class Output_data_plt_x86_64; + +// The x86_64 target class. +// See the ABI at http://www.x86-64.org/documentation/abi.pdf + +class Target_x86_64 : public Sized_target<64, false> +{ + public: + // In the x86_64 ABI, it says "The AMD64 ABI architectures uses only + // Elf64_Rela relocation entries with explicit addends." + typedef Output_data_reloc Reloc_section; + + Target_x86_64() + : Sized_target<64, false>(&x86_64_info), + got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL), + copy_relocs_(NULL), dynbss_(NULL) + { } + + // Scan the relocations to look for symbol adjustments. + void + scan_relocs(const General_options& options, + Symbol_table* symtab, + Layout* layout, + Sized_relobj<64, false>* object, + unsigned int data_shndx, + unsigned int sh_type, + const unsigned char* prelocs, + size_t reloc_count, + size_t local_symbol_count, + const unsigned char* plocal_symbols, + Symbol** global_symbols); + + // Finalize the sections. + void + do_finalize_sections(Layout*); + + // Relocate a section. + void + relocate_section(const Relocate_info<64, false>*, + unsigned int sh_type, + const unsigned char* prelocs, + size_t reloc_count, + unsigned char* view, + elfcpp::Elf_types<64>::Elf_Addr view_address, + off_t view_size); + + // Return a string used to fill a code section with nops. + std::string + do_code_fill(off_t length); + + private: + // The class which scans relocations. + struct Scan + { + inline void + local(const General_options& options, Symbol_table* symtab, + Layout* layout, Target_x86_64* target, + Sized_relobj<64, false>* object, + unsigned int data_shndx, + const elfcpp::Rela<64, false>& reloc, unsigned int r_type, + const elfcpp::Sym<64, false>& lsym); + + inline void + global(const General_options& options, Symbol_table* symtab, + Layout* layout, Target_x86_64* target, + Sized_relobj<64, false>* object, + unsigned int data_shndx, + const elfcpp::Rela<64, false>& reloc, unsigned int r_type, + Symbol* gsym); + }; + + // The class which implements relocation. + class Relocate + { + public: + Relocate() + : skip_call_tls_get_addr_(false) + { } + + ~Relocate() + { + if (this->skip_call_tls_get_addr_) + { + // FIXME: This needs to specify the location somehow. + fprintf(stderr, _("%s: missing expected TLS relocation\n"), + program_name); + gold_exit(false); + } + } + + // Do a relocation. Return false if the caller should not issue + // any warnings about this relocation. + inline bool + relocate(const Relocate_info<64, false>*, Target_x86_64*, size_t relnum, + const elfcpp::Rela<64, false>&, + unsigned int r_type, const Sized_symbol<64>*, + const Symbol_value<64>*, + unsigned char*, elfcpp::Elf_types<64>::Elf_Addr, + off_t); + + private: + // Do a TLS relocation. + inline void + relocate_tls(const Relocate_info<64, false>*, size_t relnum, + const elfcpp::Rela<64, false>&, + unsigned int r_type, const Sized_symbol<64>*, + const Symbol_value<64>*, + unsigned char*, elfcpp::Elf_types<64>::Elf_Addr, off_t); + + // Do a TLS Initial-Exec to Local-Exec transition. + static inline void + tls_ie_to_le(const Relocate_info<64, false>*, size_t relnum, + Output_segment* tls_segment, + const elfcpp::Rela<64, false>&, unsigned int r_type, + elfcpp::Elf_types<64>::Elf_Addr value, + unsigned char* view, + off_t view_size); + + // Do a TLS Global-Dynamic to Local-Exec transition. + inline void + tls_gd_to_le(const Relocate_info<64, false>*, size_t relnum, + Output_segment* tls_segment, + const elfcpp::Rela<64, false>&, unsigned int r_type, + elfcpp::Elf_types<64>::Elf_Addr value, + unsigned char* view, + off_t view_size); + + // Check the range for a TLS relocation. + static inline void + check_range(const Relocate_info<64, false>*, size_t relnum, + const elfcpp::Rela<64, false>&, off_t, off_t); + + // Check the validity of a TLS relocation. This is like assert. + static inline void + check_tls(const Relocate_info<64, false>*, size_t relnum, + const elfcpp::Rela<64, false>&, bool); + + // This is set if we should skip the next reloc, which should be a + // PLT32 reloc against ___tls_get_addr. + bool skip_call_tls_get_addr_; + }; + + // Adjust TLS relocation type based on the options and whether this + // is a local symbol. + static unsigned int + optimize_tls_reloc(bool is_final, int r_type); + + // Get the GOT section, creating it if necessary. + Output_data_got<64, false>* + got_section(Symbol_table*, Layout*); + + // Create a PLT entry for a global symbol. + void + make_plt_entry(Symbol_table*, Layout*, Symbol*); + + // Get the PLT section. + Output_data_plt_x86_64* + 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*); + + // Copy a relocation against a global symbol. + void + copy_reloc(const General_options*, Symbol_table*, Layout*, + Sized_relobj<64, false>*, unsigned int, + Symbol*, const elfcpp::Rela<64, false>&); + + // Information about this specific target which we pass to the + // general Target structure. + static const Target::Target_info x86_64_info; + + // The GOT section. + Output_data_got<64, false>* got_; + // The PLT section. + Output_data_plt_x86_64* 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<64, false>* copy_relocs_; + // Space for variables copied with a COPY reloc. + Output_data_space* dynbss_; +}; + +const Target::Target_info Target_x86_64::x86_64_info = +{ + 64, // size + false, // is_big_endian + elfcpp::EM_X86_64, // machine_code + false, // has_make_symbol + false, // has_resolve + true, // has_code_fill + "/lib/ld64.so.1", // program interpreter + 0x400000, // text_segment_address + 0x1000, // abi_pagesize + 0x1000 // common_pagesize +}; + +// Get the GOT section, creating it if necessary. + +Output_data_got<64, false>* +Target_x86_64::got_section(Symbol_table* symtab, Layout* layout) +{ + if (this->got_ == NULL) + { + gold_assert(symtab != NULL && layout != NULL); + + this->got_ = new Output_data_got<64, false>(); + + layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, + elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE, + this->got_); + + // 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. + // TODO(csilvers): do we really need an alignment of 8? + this->got_plt_ = new Output_data_space(8); + layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, + elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE, + this->got_plt_); + + // The first three entries are reserved. + this->got_plt_->set_space_size(3 * 8); + + // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT. + symtab->define_in_output_data(this, "_GLOBAL_OFFSET_TABLE_", NULL, + 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. + +Target_x86_64::Reloc_section* +Target_x86_64::rel_dyn_section(Layout* layout) +{ + if (this->rel_dyn_ == NULL) + { + gold_assert(layout != NULL); + this->rel_dyn_ = new Reloc_section(); + layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA, + elfcpp::SHF_ALLOC, this->rel_dyn_); + } + return this->rel_dyn_; +} + +// A class to handle the PLT data. + +class Output_data_plt_x86_64 : public Output_section_data +{ + public: + typedef Output_data_reloc Reloc_section; + + Output_data_plt_x86_64(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); + + private: + // The size of an entry in the PLT. + static const int plt_entry_size = 16; + + // The first entry in the PLT. + // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same + // procedure linkage table for both programs and shared objects." + static unsigned char first_plt_entry[plt_entry_size]; + + // Other entries in the PLT for an executable. + static unsigned char plt_entry[plt_entry_size]; + + // Set the final size. + void + do_set_address(uint64_t, off_t) + { this->set_data_size((this->count_ + 1) * plt_entry_size); } + + // 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. + +Output_data_plt_x86_64::Output_data_plt_x86_64(Layout* layout, + Output_data_space* got_plt) + // TODO(csilvers): do we really need an alignment of 8? + : Output_section_data(8), got_plt_(got_plt), count_(0) +{ + this->rel_ = new Reloc_section(); + layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA, + elfcpp::SHF_ALLOC, this->rel_); +} + +void +Output_data_plt_x86_64::do_adjust_output_section(Output_section* os) +{ + // UnixWare sets the entsize of .plt to 4, and so does the old GNU + // linker, and so do we. + os->set_entsize(4); +} + +// Add an entry to the PLT. + +void +Output_data_plt_x86_64::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_ + 1) * plt_entry_size); + + ++this->count_; + + off_t got_offset = this->got_plt_->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_space_size(got_offset + 8); + + // Every PLT entry needs a reloc. + gsym->set_needs_dynsym_entry(); + this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_, + got_offset, 0); + + // 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. +} + +// The first entry in the PLT for an executable. + +unsigned char Output_data_plt_x86_64::first_plt_entry[plt_entry_size] = +{ + // From AMD64 ABI Draft 0.98, page 76 + 0xff, 0x35, // pushq contents of memory address + 0, 0, 0, 0, // replaced with address of .got + 4 + 0xff, 0x25, // jmp indirect + 0, 0, 0, 0, // replaced with address of .got + 8 + 0x90, 0x90, 0x90, 0x90 // noop (x4) +}; + +// Subsequent entries in the PLT for an executable. + +unsigned char Output_data_plt_x86_64::plt_entry[plt_entry_size] = +{ + // From AMD64 ABI Draft 0.98, page 76 + 0xff, 0x25, // jmpq indirect + 0, 0, 0, 0, // replaced with address of symbol in .got + 0x68, // pushq immediate + 0, 0, 0, 0, // replaced with offset into relocation table + 0xe9, // jmpq relative + 0, 0, 0, 0 // replaced with offset to start of .plt +}; + +// Write out the PLT. This uses the hand-coded instructions above, +// and adjusts them as needed. This is specified by the AMD64 ABI. + +void +Output_data_plt_x86_64::do_write(Output_file* of) +{ + const off_t offset = this->offset(); + const off_t oview_size = 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 off_t got_size = this->got_plt_->data_size(); + unsigned char* const got_view = of->get_output_view(got_file_offset, + got_size); + + unsigned char* pov = oview; + + elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address(); + elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address(); + + memcpy(pov, first_plt_entry, plt_entry_size); + if (!parameters->output_is_shared()) + { + // We do a jmp relative to the PC at the end of this instruction. + elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 8 + - (plt_address + 6)); + elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 16 + - (plt_address + 12)); + } + pov += plt_entry_size; + + unsigned char* got_pov = got_view; + + memset(got_pov, 0, 24); + got_pov += 24; + + unsigned int plt_offset = plt_entry_size; + unsigned int got_offset = 24; + const unsigned int count = this->count_; + for (unsigned int plt_index = 0; + plt_index < count; + ++plt_index, + pov += plt_entry_size, + got_pov += 8, + plt_offset += plt_entry_size, + got_offset += 8) + { + // Set and adjust the PLT entry itself. + memcpy(pov, plt_entry, plt_entry_size); + if (parameters->output_is_shared()) + // FIXME(csilvers): what's the right thing to write here? + elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset); + else + elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, + (got_address + got_offset + - (plt_address + plt_offset + + 6))); + + elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index); + elfcpp::Swap<32, false>::writeval(pov + 12, + - (plt_offset + plt_entry_size)); + + // Set the entry in the GOT. + elfcpp::Swap<64, false>::writeval(got_pov, plt_address + plt_offset + 6); + } + + gold_assert(pov - oview == oview_size); + gold_assert(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. + +void +Target_x86_64::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_x86_64(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); +} + +// Handle a relocation against a non-function symbol defined in a +// dynamic object. The traditional way to handle this is to generate +// a COPY relocation to copy the variable at runtime from the shared +// object into the executable's data segment. However, this is +// undesirable in general, as if the size of the object changes in the +// dynamic object, the executable will no longer work correctly. If +// this relocation is in a writable section, then we can create a +// dynamic reloc and the dynamic linker will resolve it to the correct +// address at runtime. However, we do not want do that if the +// relocation is in a read-only section, as it would prevent the +// readonly segment from being shared. And if we have to eventually +// generate a COPY reloc, then any dynamic relocations will be +// useless. So this means that if this is a writable section, we need +// to save the relocation until we see whether we have to create a +// COPY relocation for this symbol for any other relocation. + +void +Target_x86_64::copy_reloc(const General_options* options, + Symbol_table* symtab, + Layout* layout, + Sized_relobj<64, false>* object, + unsigned int data_shndx, Symbol* gsym, + const elfcpp::Rela<64, false>& rel) +{ + Sized_symbol<64>* ssym; + ssym = symtab->get_sized_symbol SELECT_SIZE_NAME(64) (gsym + SELECT_SIZE(64)); + + if (!Copy_relocs<64, false>::need_copy_reloc(options, object, + data_shndx, ssym)) + { + // So far we do not need a COPY reloc. Save this relocation. + // If it turns out that we never need a COPY reloc for this + // symbol, then we will emit the relocation. + if (this->copy_relocs_ == NULL) + this->copy_relocs_ = new Copy_relocs<64, false>(); + this->copy_relocs_->save(ssym, object, data_shndx, rel); + } + else + { + // Allocate space for this symbol in the .bss section. + + elfcpp::Elf_types<64>::Elf_WXword symsize = ssym->symsize(); + + // There is no defined way to determine the required alignment + // of the symbol. We pick the alignment based on the size. We + // set an arbitrary maximum of 256. + unsigned int align; + for (align = 1; align < 512; align <<= 1) + if ((symsize & align) != 0) + break; + + if (this->dynbss_ == NULL) + { + this->dynbss_ = new Output_data_space(align); + layout->add_output_section_data(".bss", + elfcpp::SHT_NOBITS, + (elfcpp::SHF_ALLOC + | elfcpp::SHF_WRITE), + this->dynbss_); + } + + Output_data_space* dynbss = this->dynbss_; + + if (align > dynbss->addralign()) + dynbss->set_space_alignment(align); + + off_t dynbss_size = dynbss->data_size(); + dynbss_size = align_address(dynbss_size, align); + off_t offset = dynbss_size; + dynbss->set_space_size(dynbss_size + symsize); + + // Define the symbol in the .dynbss section. + symtab->define_in_output_data(this, ssym->name(), ssym->version(), + dynbss, offset, symsize, ssym->type(), + ssym->binding(), ssym->visibility(), + ssym->nonvis(), false, false); + + // Add the COPY reloc. + ssym->set_needs_dynsym_entry(); + Reloc_section* rel_dyn = this->rel_dyn_section(layout); + rel_dyn->add_global(ssym, elfcpp::R_X86_64_COPY, dynbss, offset, + rel.get_r_addend()); + } +} + + +// 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. + +unsigned int +Target_x86_64::optimize_tls_reloc(bool is_final, int r_type) +{ + return is_final ? r_type : 0; +#if 0 + // If we are generating a shared library, then we can't do anything + // in the linker. + if (parameters->output_is_shared()) + return r_type; + + switch (r_type) + { + case elfcpp::R_X86_64_TLSGD: + // These are Global-Dynamic which permits fully general TLS + // access. Since we know that we are generating an executable, + // we can convert this to Initial-Exec. If we also know that + // this is a local symbol, we can further switch to Local-Exec. + if (is_final) + return elfcpp::R_X86_64_TLS_LE_64; + return elfcpp::R_X86_64_TLS_IE_64; + + case elfcpp::R_X86_64_TLS_LDM: + // This is Local-Dynamic, which refers to a local symbol in the + // dynamic TLS block. Since we know that we generating an + // executable, we can switch to Local-Exec. + return elfcpp::R_X86_64_TLS_LE_64; + + case elfcpp::R_X86_64_TLS_LDO_64: + // Another type of Local-Dynamic relocation. + return elfcpp::R_X86_64_TLS_LE; + + case elfcpp::R_X86_64_TLS_IE: + case elfcpp::R_X86_64_TLS_GOTIE: + case elfcpp::R_X86_64_TLS_IE_64: + // These are Initial-Exec relocs which get the thread offset + // from the GOT. If we know that we are linking against the + // local symbol, we can switch to Local-Exec, which links the + // thread offset into the instruction. + if (is_final) + return elfcpp::R_X86_64_TLS_LE_64; + return r_type; + + case elfcpp::R_X86_64_TLS_LE: + case elfcpp::R_X86_64_TLS_LE_64: + // When we already have Local-Exec, there is nothing further we + // can do. + return r_type; + + default: + gold_unreachable(); + } +#endif +} + +// Scan a relocation for a local symbol. + +inline void +Target_x86_64::Scan::local(const General_options&, + Symbol_table* symtab, + Layout* layout, + Target_x86_64* target, + Sized_relobj<64, false>* object, + unsigned int, + const elfcpp::Rela<64, false>&, + unsigned int r_type, + const elfcpp::Sym<64, false>&) +{ + switch (r_type) + { + case elfcpp::R_X86_64_NONE: + break; + + case elfcpp::R_X86_64_64: + case elfcpp::R_X86_64_32: + case elfcpp::R_X86_64_32S: + case elfcpp::R_X86_64_16: + case elfcpp::R_X86_64_8: + // FIXME: If we are generating a shared object we need to copy + // this relocation into the object. + gold_assert(!parameters->output_is_shared()); + break; + + case elfcpp::R_X86_64_PC64: + case elfcpp::R_X86_64_PC32: + case elfcpp::R_X86_64_PC16: + case elfcpp::R_X86_64_PC8: + break; + + case elfcpp::R_X86_64_GOTOFF64: + case elfcpp::R_X86_64_GOTPCREL: + // We need a GOT section. + target->got_section(symtab, layout); + break; + + case elfcpp::R_X86_64_COPY: + case elfcpp::R_X86_64_GLOB_DAT: + case elfcpp::R_X86_64_JUMP_SLOT: + case elfcpp::R_X86_64_RELATIVE: + case elfcpp::R_X86_64_TPOFF64: + case elfcpp::R_X86_64_TPOFF32: + case elfcpp::R_X86_64_DTPMOD64: + case elfcpp::R_X86_64_DTPOFF64: + case elfcpp::R_X86_64_DTPOFF32: + case elfcpp::R_X86_64_TLSDESC: + fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"), + program_name, object->name().c_str(), r_type); + gold_exit(false); + break; + +#if 0 + case elfcpp::R_X86_64_TLS_IE: + case elfcpp::R_X86_64_TLS_GOTIE: + case elfcpp::R_X86_64_TLS_LE: + case elfcpp::R_X86_64_TLS_GD: + case elfcpp::R_X86_64_TLS_LDM: + case elfcpp::R_X86_64_TLS_LDO_64: + case elfcpp::R_X86_64_TLS_IE_64: + case elfcpp::R_X86_64_TLS_LE_64: + { + bool output_is_shared = parameters->output_is_shared(); + r_type = Target_x86_64::optimize_tls_reloc(!output_is_shared, + r_type); + switch (r_type) + { + case elfcpp::R_X86_64_TLS_LE: + case elfcpp::R_X86_64_TLS_LE_64: + // FIXME: If generating a shared object, we need to copy + // this relocation into the object. + gold_assert(!output_is_shared); + break; + + case elfcpp::R_X86_64_TLS_IE: + case elfcpp::R_X86_64_TLS_GOTIE: + case elfcpp::R_X86_64_TLS_GD: + case elfcpp::R_X86_64_TLS_LDM: + case elfcpp::R_X86_64_TLS_LDO_64: + case elfcpp::R_X86_64_TLS_IE_64: + fprintf(stderr, + _("%s: %s: unsupported reloc %u against local symbol\n"), + program_name, object->name().c_str(), r_type); + break; + } + } + break; +#endif + +#if 0 + case elfcpp::R_X86_64_GOT32: + case elfcpp::R_X86_64_PLT32: + case elfcpp::R_X86_64_TLS_GD_64: + case elfcpp::R_X86_64_TLS_GD_PUSH: + case elfcpp::R_X86_64_TLS_GD_CALL: + case elfcpp::R_X86_64_TLS_GD_POP: + case elfcpp::R_X86_64_TLS_LDM_64: + case elfcpp::R_X86_64_TLS_LDM_PUSH: + case elfcpp::R_X86_64_TLS_LDM_CALL: + case elfcpp::R_X86_64_TLS_LDM_POP: +#endif + default: + fprintf(stderr, _("%s: %s: unsupported reloc %u against local symbol\n"), + program_name, object->name().c_str(), r_type); + break; + } +} + + +// Scan a relocation for a global symbol. + +inline void +Target_x86_64::Scan::global(const General_options& options, + Symbol_table* symtab, + Layout* layout, + Target_x86_64* target, + Sized_relobj<64, false>* object, + unsigned int data_shndx, + const elfcpp::Rela<64, false>& reloc, + unsigned int r_type, + Symbol* gsym) +{ + switch (r_type) + { + case elfcpp::R_X86_64_NONE: + break; + + case elfcpp::R_X86_64_64: + case elfcpp::R_X86_64_PC64: + case elfcpp::R_X86_64_32: + case elfcpp::R_X86_64_32S: + case elfcpp::R_X86_64_PC32: + case elfcpp::R_X86_64_16: + case elfcpp::R_X86_64_PC16: + case elfcpp::R_X86_64_8: + case elfcpp::R_X86_64_PC8: + // FIXME: If we are generating a shared object we may need to + // copy this relocation into the object. If this symbol is + // defined in a shared object, we may need to copy this + // relocation in order to avoid a COPY relocation. + gold_assert(!parameters->output_is_shared()); + + if (gsym->is_from_dynobj()) + { + // This symbol is defined in a dynamic object. If it is a + // function, we make a PLT entry. Otherwise we need to + // either generate a COPY reloc or copy this reloc. + if (gsym->type() == elfcpp::STT_FUNC) + target->make_plt_entry(symtab, layout, gsym); + else + target->copy_reloc(&options, symtab, layout, object, data_shndx, + gsym, reloc); + } + + break; + + case elfcpp::R_X86_64_GOT32: + { + // The symbol requires a GOT entry. + Output_data_got<64, false>* got = target->got_section(symtab, layout); + if (got->add_global(gsym)) + { + // If this symbol is not fully resolved, we need to add a + // dynamic relocation for it. + if (!gsym->final_value_is_known()) + { + Reloc_section* rel_dyn = target->rel_dyn_section(layout); + rel_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT, got, + gsym->got_offset(), reloc.get_r_addend()); + } + } + } + break; + + case elfcpp::R_X86_64_PLT32: + // If the symbol is fully resolved, this is just a PC32 reloc. + // Otherwise we need a PLT entry. + if (gsym->final_value_is_known()) + break; + target->make_plt_entry(symtab, layout, gsym); + break; + + case elfcpp::R_X86_64_GOTOFF64: + case elfcpp::R_X86_64_GOTPC32: + case elfcpp::R_X86_64_GOTPCREL: + // We need a GOT section. + target->got_section(symtab, layout); + break; + +#if 0 + case elfcpp::R_X86_64_COPY: + case elfcpp::R_X86_64_GLOB_DAT: + case elfcpp::R_X86_64_JUMP_SLOT: + case elfcpp::R_X86_64_RELATIVE: + case elfcpp::R_X86_64_TLS_TPOFF: + case elfcpp::R_X86_64_DTPMOD64: + case elfcpp::R_X86_64_DTPOFF64: + case elfcpp::R_X86_64_DTPOFF32: + case elfcpp::R_X86_64_TLS_TPOFF64: + case elfcpp::R_X86_64_TLS_DESC: + fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"), + program_name, object->name().c_str(), r_type); + gold_exit(false); + break; +#endif + +#if 0 + case elfcpp::R_X86_64_TLS_IE: + case elfcpp::R_X86_64_TLS_GOTIE: + case elfcpp::R_X86_64_TLS_LE: + case elfcpp::R_X86_64_TLS_GD: + case elfcpp::R_X86_64_TLS_LDM: + case elfcpp::R_X86_64_TLS_LDO_64: + case elfcpp::R_X86_64_TLS_IE_64: + case elfcpp::R_X86_64_TLS_LE_64: + { + const bool is_final = gsym->final_value_is_known(); + r_type = Target_x86_64::optimize_tls_reloc(is_final, r_type); + switch (r_type) + { + case elfcpp::R_X86_64_TLS_LE: + case elfcpp::R_X86_64_TLS_LE_64: + // FIXME: If generating a shared object, we need to copy + // this relocation into the object. + gold_assert(!parameters->output_is_shared()); + break; + + case elfcpp::R_X86_64_TLS_IE: + case elfcpp::R_X86_64_TLS_GOTIE: + case elfcpp::R_X86_64_TLS_GD: + case elfcpp::R_X86_64_TLS_LDM: + case elfcpp::R_X86_64_TLS_LDO_64: + case elfcpp::R_X86_64_TLS_IE_64: + fprintf(stderr, + _("%s: %s: unsupported reloc %u " + "against global symbol %s\n"), + program_name, object->name().c_str(), r_type, + gsym->name()); + break; + } + } + break; +#endif + +#if 0 + case elfcpp::R_X86_64_TLS_GD_64: + case elfcpp::R_X86_64_TLS_GD_PUSH: + case elfcpp::R_X86_64_TLS_GD_CALL: + case elfcpp::R_X86_64_TLS_GD_POP: + case elfcpp::R_X86_64_TLS_LDM_64: + case elfcpp::R_X86_64_TLS_LDM_PUSH: + case elfcpp::R_X86_64_TLS_LDM_CALL: + case elfcpp::R_X86_64_TLS_LDM_POP: +#endif + default: + fprintf(stderr, + _("%s: %s: unsupported reloc %u against global symbol %s\n"), + program_name, object->name().c_str(), r_type, gsym->name()); + break; + } +} + +// Scan relocations for a section. + +void +Target_x86_64::scan_relocs(const General_options& options, + Symbol_table* symtab, + Layout* layout, + Sized_relobj<64, false>* object, + unsigned int data_shndx, + unsigned int sh_type, + const unsigned char* prelocs, + size_t reloc_count, + size_t local_symbol_count, + const unsigned char* plocal_symbols, + Symbol** global_symbols) +{ + if (sh_type == elfcpp::SHT_REL) + { + fprintf(stderr, _("%s: %s: unsupported REL reloc section\n"), + program_name, object->name().c_str()); + gold_exit(false); + } + + gold::scan_relocs<64, false, Target_x86_64, elfcpp::SHT_RELA, + Target_x86_64::Scan>( + options, + symtab, + layout, + this, + object, + data_shndx, + prelocs, + reloc_count, + local_symbol_count, + plocal_symbols, + global_symbols); +} + +// Finalize the sections. + +void +Target_x86_64::do_finalize_sections(Layout* layout) +{ + // Fill in some more dynamic tags. + Output_data_dynamic* const odyn = layout->dynamic_data(); + if (odyn != NULL) + { + if (this->got_plt_ != NULL) + odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_); + + if (this->plt_ != NULL) + { + 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_RELA); + } + + if (this->rel_dyn_ != NULL) + { + const Output_data* od = this->rel_dyn_; + odyn->add_section_address(elfcpp::DT_RELA, od); + odyn->add_section_size(elfcpp::DT_RELSZ, od); + odyn->add_constant(elfcpp::DT_RELAENT, + elfcpp::Elf_sizes<64>::rel_size); + } + + if (!parameters->output_is_shared()) + { + // 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); + } + } + + // Emit any relocs we saved in an attempt to avoid generating COPY + // relocs. + if (this->copy_relocs_ == NULL) + return; + if (this->copy_relocs_->any_to_emit()) + { + Reloc_section* rel_dyn = this->rel_dyn_section(layout); + this->copy_relocs_->emit(rel_dyn); + } + delete this->copy_relocs_; + this->copy_relocs_ = NULL; +} + +// Perform a relocation. + +inline bool +Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, + Target_x86_64* target, + size_t relnum, + const elfcpp::Rela<64, false>& rel, + unsigned int r_type, + const Sized_symbol<64>* gsym, + const Symbol_value<64>* psymval, + unsigned char* view, + elfcpp::Elf_types<64>::Elf_Addr address, + off_t view_size) +{ + if (this->skip_call_tls_get_addr_) + { + if (r_type != elfcpp::R_X86_64_PLT32 + || gsym == NULL + || strcmp(gsym->name(), "___tls_get_addr") != 0) + { + fprintf(stderr, _("%s: %s: missing expected TLS relocation\n"), + program_name, + relinfo->location(relnum, rel.get_r_offset()).c_str()); + gold_exit(false); + } + + this->skip_call_tls_get_addr_ = false; + + return false; + } + + // Pick the value to use for symbols defined in shared objects. + Symbol_value<64> symval; + if (gsym != NULL && gsym->is_from_dynobj() && gsym->has_plt_offset()) + { + symval.set_output_value(target->plt_section()->address() + + gsym->plt_offset()); + psymval = &symval; + } + + const Sized_relobj<64, false>* object = relinfo->object; + const elfcpp::Elf_Xword addend = rel.get_r_addend(); + + switch (r_type) + { + case elfcpp::R_X86_64_NONE: + break; + + case elfcpp::R_X86_64_64: + Relocate_functions<64, false>::rela64(view, object, psymval, addend); + break; + + case elfcpp::R_X86_64_PC64: + Relocate_functions<64, false>::pcrela64(view, object, psymval, addend, + address); + break; + + case elfcpp::R_X86_64_32: + // FIXME: Needs error checking. + Relocate_functions<64, false>::rela32(view, object, psymval, addend); + break; + + case elfcpp::R_X86_64_32S: + // FIXME: Needs error checking. + Relocate_functions<64, false>::rela32(view, object, psymval, addend); + break; + + case elfcpp::R_X86_64_PC32: + Relocate_functions<64, false>::pcrela32(view, object, psymval, addend, + address); + break; + + case elfcpp::R_X86_64_16: + Relocate_functions<64, false>::rela16(view, object, psymval, addend); + break; + + case elfcpp::R_X86_64_PC16: + Relocate_functions<64, false>::pcrela16(view, object, psymval, addend, + address); + break; + + case elfcpp::R_X86_64_8: + Relocate_functions<64, false>::rela8(view, object, psymval, addend); + break; + + case elfcpp::R_X86_64_PC8: + Relocate_functions<64, false>::pcrela8(view, object, psymval, addend, + address); + break; + + case elfcpp::R_X86_64_PLT32: + gold_assert(gsym->has_plt_offset() + || gsym->final_value_is_known()); + Relocate_functions<64, false>::pcrela32(view, object, psymval, addend, + address); + break; + + case elfcpp::R_X86_64_GOT32: + // Local GOT offsets not yet supported. + gold_assert(gsym); + gold_assert(gsym->has_got_offset()); + Relocate_functions<64, false>::rela32(view, gsym->got_offset(), addend); + break; + + case elfcpp::R_X86_64_GOTOFF64: + { + elfcpp::Elf_types<64>::Elf_Addr value; + value = (psymval->value(object, 0) + - target->got_section(NULL, NULL)->address()); + Relocate_functions<64, false>::rela64(view, value, addend); + } + break; + + case elfcpp::R_X86_64_GOTPCREL: + { + gold_assert(gsym); + elfcpp::Elf_types<64>::Elf_Addr value; + // FIXME(csilvers): this is probably totally wrong for G + GOT + value = (target->got_section(NULL, NULL)->address() + + (gsym->has_got_offset() ? gsym->got_offset() : 0)); + Relocate_functions<64, false>::pcrela32(view, value, addend, address); + } + break; + + case elfcpp::R_X86_64_COPY: + case elfcpp::R_X86_64_GLOB_DAT: + case elfcpp::R_X86_64_JUMP_SLOT: + case elfcpp::R_X86_64_RELATIVE: + case elfcpp::R_X86_64_TPOFF64: + case elfcpp::R_X86_64_TPOFF32: + case elfcpp::R_X86_64_DTPMOD64: + case elfcpp::R_X86_64_DTPOFF64: + case elfcpp::R_X86_64_DTPOFF32: + case elfcpp::R_X86_64_TLSDESC: + fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"), + program_name, + relinfo->location(relnum, rel.get_r_offset()).c_str(), + r_type); + gold_exit(false); + break; + +#if 0 + case elfcpp::R_X86_64_TLS_IE: + case elfcpp::R_X86_64_TLS_GOTIE: + case elfcpp::R_X86_64_TLS_LE: + case elfcpp::R_X86_64_TLS_GD: + case elfcpp::R_X86_64_TLS_LDM: + case elfcpp::R_X86_64_TLS_LDO_64: + case elfcpp::R_X86_64_TLS_IE_64: + case elfcpp::R_X86_64_TLS_LE_64: + this->relocate_tls(relinfo, relnum, rel, r_type, gsym, psymval, view, + address, view_size); + break; +#else + view_size++; // this is to make view_size used +#endif + +#if 0 + case elfcpp::R_X86_64_TLS_GD_64: + case elfcpp::R_X86_64_TLS_GD_PUSH: + case elfcpp::R_X86_64_TLS_GD_CALL: + case elfcpp::R_X86_64_TLS_GD_POP: + case elfcpp::R_X86_64_TLS_LDM_64: + case elfcpp::R_X86_64_TLS_LDM_PUSH: + case elfcpp::R_X86_64_TLS_LDM_CALL: + case elfcpp::R_X86_64_TLS_LDM_POP: +#endif + default: + fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), + program_name, + relinfo->location(relnum, rel.get_r_offset()).c_str(), + r_type); + // gold_exit(false); + break; + } + + return true; +} + +// Perform a TLS relocation. + +inline void +Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>*, // relinfo, + size_t , // relnum, + const elfcpp::Rela<64, false>& , // rel, + unsigned int , // r_type, + const Sized_symbol<64>* , // gsym, + const Symbol_value<64>* , // psymval, + unsigned char* , // view, + elfcpp::Elf_types<64>::Elf_Addr, + off_t)// view_size) +{ +#if 0 + Output_segment* tls_segment = relinfo->layout->tls_segment(); + if (tls_segment == NULL) + { + fprintf(stderr, _("%s: %s: TLS reloc but no TLS segment\n"), + program_name, + relinfo->location(relnum, rel.get_r_offset()).c_str()); + gold_exit(false); + } + + elfcpp::Elf_types<64>::Elf_Addr value = psymval->value(relinfo->object, 0); + + const bool is_final = (gsym == NULL + ? !parameters->output_is_shared() + : gsym->final_value_is_known()); + const unsigned int opt_r_type = + Target_x86_64::optimize_tls_reloc(is_final, r_type); + switch (r_type) + { + case elfcpp::R_X86_64_TLS_LE_64: + value = tls_segment->vaddr() + tls_segment->memsz() - value; + Relocate_functions<64, false>::rel64(view, value); + break; + + case elfcpp::R_X86_64_TLS_LE: + value = value - (tls_segment->vaddr() + tls_segment->memsz()); + Relocate_functions<64, false>::rel64(view, value); + break; + + case elfcpp::R_X86_64_TLS_IE: + case elfcpp::R_X86_64_TLS_GOTIE: + case elfcpp::R_X86_64_TLS_IE_64: + if (opt_r_type == elfcpp::R_X86_64_TLS_LE_64) + { + Target_x86_64::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment, + rel, r_type, value, view, + view_size); + break; + } + fprintf(stderr, _("%s: %s: unsupported reloc type %u\n"), + program_name, + relinfo->location(relnum, rel.get_r_offset()).c_str(), + r_type); + // gold_exit(false); + break; + + case elfcpp::R_X86_64_TLS_GD: + if (opt_r_type == elfcpp::R_X86_64_TLS_LE_64) + { + this->tls_gd_to_le(relinfo, relnum, tls_segment, + rel, r_type, value, view, + view_size); + break; + } + fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), + program_name, + relinfo->location(relnum, rel.get_r_offset()).c_str(), + r_type); + // gold_exit(false); + break; + + case elfcpp::R_X86_64_TLS_LDM: + case elfcpp::R_X86_64_TLS_LDO_64: + fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), + program_name, + relinfo->location(relnum, rel.get_r_offset()).c_str(), + r_type); + // gold_exit(false); + break; + } +#endif +} + +// Do a relocation in which we convert a TLS Initial-Exec to a +// Local-Exec. + +inline void +Target_x86_64::Relocate::tls_ie_to_le(const Relocate_info<64, false>* , // relinfo, + size_t , // relnum, + Output_segment* , // tls_segment, + const elfcpp::Rela<64, false>& , // rel, + unsigned int , // r_type, + elfcpp::Elf_types<64>::Elf_Addr , // value, + unsigned char* , // view, + off_t) // view_size) +{ +#if 0 + // We have to actually change the instructions, which means that we + // need to examine the opcodes to figure out which instruction we + // are looking at. + if (r_type == elfcpp::R_X86_64_TLS_IE) + { + // movl %gs:XX,%eax ==> movl $YY,%eax + // movl %gs:XX,%reg ==> movl $YY,%reg + // addl %gs:XX,%reg ==> addl $YY,%reg + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -1); + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 4); + + unsigned char op1 = view[-1]; + if (op1 == 0xa1) + { + // movl XX,%eax ==> movl $YY,%eax + view[-1] = 0xb8; + } + else + { + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, + view_size, -2); + + unsigned char op2 = view[-2]; + if (op2 == 0x8b) + { + // movl XX,%reg ==> movl $YY,%reg + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, + (op1 & 0xc7) == 0x05); + view[-2] = 0xc7; + view[-1] = 0xc0 | ((op1 >> 3) & 7); + } + else if (op2 == 0x03) + { + // addl XX,%reg ==> addl $YY,%reg + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, + (op1 & 0xc7) == 0x05); + view[-2] = 0x81; + view[-1] = 0xc0 | ((op1 >> 3) & 7); + } + else + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, 0); + } + } + else + { + // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2 + // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2 + // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2 + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -2); + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 4); + + unsigned char op1 = view[-1]; + unsigned char op2 = view[-2]; + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, + (op1 & 0xc0) == 0x80 && (op1 & 7) != 4); + if (op2 == 0x8b) + { + // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2 + view[-2] = 0xc7; + view[-1] = 0xc0 | ((op1 >> 3) & 7); + } + else if (op2 == 0x2b) + { + // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2 + view[-2] = 0x81; + view[-1] = 0xe8 | ((op1 >> 3) & 7); + } + else if (op2 == 0x03) + { + // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2 + view[-2] = 0x81; + view[-1] = 0xc0 | ((op1 >> 3) & 7); + } + else + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, 0); + } + + value = tls_segment->vaddr() + tls_segment->memsz() - value; + if (r_type == elfcpp::R_X86_64_TLS_IE || r_type == elfcpp::R_X86_64_TLS_GOTIE) + value = - value; + + Relocate_functions<64, false>::rel64(view, value); +#endif +} + +// Do a relocation in which we convert a TLS Global-Dynamic to a +// Local-Exec. + +inline void +Target_x86_64::Relocate::tls_gd_to_le(const Relocate_info<64, false>* , // relinfo, + size_t , // relnum, + Output_segment* , // tls_segment, + const elfcpp::Rela<64, false>& , // rel, + unsigned int, + elfcpp::Elf_types<64>::Elf_Addr , // value, + unsigned char* , // view, + off_t)// view_size) +{ +#if 0 + // leal foo(,%reg,1),%eax; call ___tls_get_addr + // ==> movl %gs,0,%eax; subl $foo@tpoff,%eax + // leal foo(%reg),%eax; call ___tls_get_addr + // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax + + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -2); + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 9); + + unsigned char op1 = view[-1]; + unsigned char op2 = view[-2]; + + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, + op2 == 0x8d || op2 == 0x04); + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, + view[4] == 0xe8); + + int roff = 5; + + if (op2 == 0x04) + { + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -3); + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, + view[-3] == 0x8d); + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, + ((op1 & 0xc7) == 0x05 + && op1 != (4 << 3))); + memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); + } + else + { + Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, + (op1 & 0xf8) == 0x80 && (op1 & 7) != 4); + if (rel.get_r_offset() + 9 < view_size && view[9] == 0x90) + { + // There is a trailing nop. Use the size byte subl. + memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); + roff = 6; + } + else + { + // Use the five byte subl. + memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11); + } + } + + value = tls_segment->vaddr() + tls_segment->memsz() - value; + Relocate_functions<64, false>::rel64(view + roff, value); + + // The next reloc should be a PLT32 reloc against __tls_get_addr. + // We can skip it. + this->skip_call_tls_get_addr_ = true; +#endif +} + +// Check the range for a TLS relocation. + +inline void +Target_x86_64::Relocate::check_range(const Relocate_info<64, false>* relinfo, + size_t relnum, + const elfcpp::Rela<64, false>& rel, + off_t view_size, off_t off) +{ + off_t offset = rel.get_r_offset() + off; + if (offset < 0 || offset > view_size) + { + fprintf(stderr, _("%s: %s: TLS relocation out of range\n"), + program_name, + relinfo->location(relnum, rel.get_r_offset()).c_str()); + gold_exit(false); + } +} + +// Check the validity of a TLS relocation. This is like assert. + +inline void +Target_x86_64::Relocate::check_tls(const Relocate_info<64, false>* relinfo, + size_t relnum, + const elfcpp::Rela<64, false>& rel, + bool valid) +{ + if (!valid) + { + fprintf(stderr, + _("%s: %s: TLS relocation against invalid instruction\n"), + program_name, + relinfo->location(relnum, rel.get_r_offset()).c_str()); + gold_exit(false); + } +} + +// Relocate section data. + +void +Target_x86_64::relocate_section(const Relocate_info<64, false>* relinfo, + unsigned int sh_type, + const unsigned char* prelocs, + size_t reloc_count, + unsigned char* view, + elfcpp::Elf_types<64>::Elf_Addr address, + off_t view_size) +{ + gold_assert(sh_type == elfcpp::SHT_RELA); + + gold::relocate_section<64, false, Target_x86_64, elfcpp::SHT_RELA, + Target_x86_64::Relocate>( + relinfo, + this, + prelocs, + reloc_count, + view, + address, + view_size); +} + +// Return a string used to fill a code section with nops to take up +// the specified length. + +std::string +Target_x86_64::do_code_fill(off_t length) +{ + if (length >= 16) + { + // Build a jmpq instruction to skip over the bytes. + unsigned char jmp[5]; + jmp[0] = 0xe9; + elfcpp::Swap_unaligned<64, false>::writeval(jmp + 1, length - 5); + return (std::string(reinterpret_cast(&jmp[0]), 5) + + std::string(length - 5, '\0')); + } + + // Nop sequences of various lengths. + const char nop1[1] = { 0x90 }; // nop + const char nop2[2] = { 0x66, 0x90 }; // xchg %ax %ax + const char nop3[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi + const char nop4[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi + const char nop5[5] = { 0x90, 0x8d, 0x74, 0x26, // nop + 0x00 }; // leal 0(%esi,1),%esi + const char nop6[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi + 0x00, 0x00 }; + const char nop7[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi + 0x00, 0x00, 0x00 }; + const char nop8[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop + 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi + const char nop9[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi + 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi + 0x00 }; + const char nop10[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi + 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi + 0x00, 0x00 }; + const char nop11[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi + 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi + 0x00, 0x00, 0x00 }; + const char nop12[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi + 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi + 0x00, 0x00, 0x00, 0x00 }; + const char nop13[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi + 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi + 0x27, 0x00, 0x00, 0x00, + 0x00 }; + const char nop14[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi + 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi + 0xbc, 0x27, 0x00, 0x00, + 0x00, 0x00 }; + const char nop15[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15 + 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,... + 0x90, 0x90, 0x90, 0x90, + 0x90, 0x90, 0x90 }; + + const char* nops[16] = { + NULL, + nop1, nop2, nop3, nop4, nop5, nop6, nop7, + nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15 + }; + + return std::string(nops[length], length); +} + +// The selector for x86_64 object files. + +class Target_selector_x86_64 : public Target_selector +{ +public: + Target_selector_x86_64() + : Target_selector(elfcpp::EM_X86_64, 64, false) + { } + + Target* + recognize(int machine, int osabi, int abiversion); + + private: + Target_x86_64* target_; +}; + +// Recognize an x86_64 object file when we already know that the machine +// number is EM_X86_64. + +Target* +Target_selector_x86_64::recognize(int, int, int) +{ + if (this->target_ == NULL) + this->target_ = new Target_x86_64(); + return this->target_; +} + +Target_selector_x86_64 target_selector_x86_64; + +} // End anonymous namespace. -- 2.30.2