diff options
Diffstat (limited to 'gold')
| -rw-r--r-- | gold/x86_64.cc | 307 |
1 files changed, 172 insertions, 135 deletions
diff --git a/gold/x86_64.cc b/gold/x86_64.cc index 48b185b..d6bf019 100644 --- a/gold/x86_64.cc +++ b/gold/x86_64.cc @@ -57,7 +57,7 @@ class Output_data_plt_x86_64; // http://www.x86-64.org/documentation/abi.pdf // TLS info comes from // http://people.redhat.com/drepper/tls.pdf -// http://ia32-abi.googlegroups.com/web/RFC-TLSDESC-x86.txt?gda=kWQJPEQAAACEfYQFX0dubPQ2NuO4whhjkR4HAp8tBMb_I0iuUeQslmG1qiJ7UbTIup-M2XPURDRiZJyPR4BqKR2agJ-5jfT5Ley2_-oiOJ4zLNAGCw24Bg +// http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt class Target_x86_64 : public Sized_target<64, false> { @@ -68,7 +68,7 @@ class Target_x86_64 : public Sized_target<64, false> Target_x86_64() : Sized_target<64, false>(&x86_64_info), - got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL), + got_(NULL), plt_(NULL), got_plt_(NULL), rela_dyn_(NULL), copy_relocs_(NULL), dynbss_(NULL) { } @@ -224,7 +224,7 @@ class Target_x86_64 : public Sized_target<64, false> // Get the dynamic reloc section, creating it if necessary. Reloc_section* - rel_dyn_section(Layout*); + rela_dyn_section(Layout*); // Copy a relocation against a global symbol. void @@ -243,7 +243,7 @@ class Target_x86_64 : public Sized_target<64, false> // The GOT PLT section. Output_data_space* got_plt_; // The dynamic reloc section. - Reloc_section* rel_dyn_; + Reloc_section* rela_dyn_; // Relocs saved to avoid a COPY reloc. Copy_relocs<64, false>* copy_relocs_; // Space for variables copied with a COPY reloc. @@ -307,16 +307,16 @@ Target_x86_64::got_section(Symbol_table* symtab, Layout* layout) // Get the dynamic reloc section, creating it if necessary. Target_x86_64::Reloc_section* -Target_x86_64::rel_dyn_section(Layout* layout) +Target_x86_64::rela_dyn_section(Layout* layout) { - if (this->rel_dyn_ == NULL) + if (this->rela_dyn_ == NULL) { gold_assert(layout != NULL); - this->rel_dyn_ = new Reloc_section(); + this->rela_dyn_ = new Reloc_section(); layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA, - elfcpp::SHF_ALLOC, this->rel_dyn_); + elfcpp::SHF_ALLOC, this->rela_dyn_); } - return this->rel_dyn_; + return this->rela_dyn_; } // A class to handle the PLT data. @@ -624,8 +624,8 @@ Target_x86_64::copy_reloc(const General_options* options, // 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, 0); + Reloc_section* rela_dyn = this->rela_dyn_section(layout); + rela_dyn->add_global(ssym, elfcpp::R_X86_64_COPY, dynbss, offset, 0); } } @@ -661,6 +661,14 @@ Target_x86_64::optimize_tls_reloc(bool is_final, int r_type) // executable, we can switch to Local-Exec. return elfcpp::R_X86_64_TPOFF32; + case elfcpp::R_X86_64_DTPOFF32: + // Another Local-Dynamic reloc. + return elfcpp::R_X86_64_TPOFF32; + + case elfcpp::R_X86_64_DTPOFF64: + // Another Local-Dynamic reloc. + return elfcpp::R_X86_64_TPOFF64; + case elfcpp::R_X86_64_GOTTPOFF: // These are Initial-Exec relocs which get the thread offset // from the GOT. If we know that we are linking against the @@ -688,8 +696,8 @@ Target_x86_64::Scan::local(const General_options&, Layout* layout, Target_x86_64* target, Sized_relobj<64, false>* object, - unsigned int, - const elfcpp::Rela<64, false>&, + unsigned int data_shndx, + const elfcpp::Rela<64, false>& reloc, unsigned int r_type, const elfcpp::Sym<64, false>&) { @@ -724,6 +732,28 @@ Target_x86_64::Scan::local(const General_options&, target->got_section(symtab, layout); break; + case elfcpp::R_X86_64_GOT64: + case elfcpp::R_X86_64_GOT32: + case elfcpp::R_X86_64_GOTPCREL64: + case elfcpp::R_X86_64_GOTPCREL: + { + // The symbol requires a GOT entry. + Output_data_got<64, false>* got = target->got_section(symtab, layout); + unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info()); + if (got->add_local(object, r_sym)) + { + // If we are generating a shared object, we need to add a + // dynamic RELATIVE relocation for this symbol. + if (parameters->output_is_shared()) + { + Reloc_section* rela_dyn = target->rela_dyn_section(layout); + rela_dyn->add_local(object, 0, elfcpp::R_X86_64_RELATIVE, + data_shndx, reloc.get_r_offset(), 0); + } + } + } + break; + case elfcpp::R_X86_64_COPY: case elfcpp::R_X86_64_GLOB_DAT: case elfcpp::R_X86_64_JUMP_SLOT: @@ -731,8 +761,6 @@ Target_x86_64::Scan::local(const General_options&, // These are outstanding tls relocs, which are unexpected when linking case elfcpp::R_X86_64_TPOFF64: 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); @@ -746,17 +774,24 @@ Target_x86_64::Scan::local(const General_options&, case elfcpp::R_X86_64_TPOFF32: // TODO(csilvers): correct? case elfcpp::R_X86_64_GOTPC32_TLSDESC: // TODO(csilvers): correct? case elfcpp::R_X86_64_TLSDESC_CALL: // TODO(csilvers): correct? + case elfcpp::R_X86_64_DTPOFF32: + case elfcpp::R_X86_64_DTPOFF64: { 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_TPOFF32: // Local-exec + case elfcpp::R_X86_64_TPOFF64: // 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_DTPOFF32: + case elfcpp::R_X86_64_DTPOFF64: + break; + case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec case elfcpp::R_X86_64_TLSGD: // General Dynamic case elfcpp::R_X86_64_TLSLD: // Local Dynamic @@ -770,11 +805,7 @@ Target_x86_64::Scan::local(const General_options&, } break; - case elfcpp::R_X86_64_GOT64: // TODO(csilvers): correct? - case elfcpp::R_X86_64_GOT32: - case elfcpp::R_X86_64_GOTPCREL64: // TODO(csilvers): correct? - case elfcpp::R_X86_64_GOTPCREL: - case elfcpp::R_X86_64_GOTPLT64: // TODO(csilvers): correct? + case elfcpp::R_X86_64_GOTPLT64: case elfcpp::R_X86_64_PLT32: case elfcpp::R_X86_64_SIZE32: // TODO(csilvers): correct? case elfcpp::R_X86_64_SIZE64: // TODO(csilvers): correct? @@ -861,9 +892,9 @@ Target_x86_64::Scan::global(const General_options& options, // 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(), 0); + Reloc_section* rela_dyn = target->rela_dyn_section(layout); + rela_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT, got, + gsym->got_offset(), 0); } } } @@ -892,8 +923,6 @@ Target_x86_64::Scan::global(const General_options& options, // These are outstanding tls relocs, which are unexpected when linking case elfcpp::R_X86_64_TPOFF64: 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); @@ -907,17 +936,24 @@ Target_x86_64::Scan::global(const General_options& options, case elfcpp::R_X86_64_TPOFF32: // TODO(csilvers): correct? case elfcpp::R_X86_64_GOTPC32_TLSDESC: // TODO(csilvers): correct? case elfcpp::R_X86_64_TLSDESC_CALL: // TODO(csilvers): correct? + case elfcpp::R_X86_64_DTPOFF32: + case elfcpp::R_X86_64_DTPOFF64: { 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_TPOFF32: // Local-exec + case elfcpp::R_X86_64_TPOFF64: // 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_DTPOFF32: + case elfcpp::R_X86_64_DTPOFF64: + break; + case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec case elfcpp::R_X86_64_TLSGD: // General Dynamic case elfcpp::R_X86_64_TLSLD: // Local Dynamic @@ -1000,9 +1036,9 @@ Target_x86_64::do_finalize_sections(Layout* layout) odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_RELA); } - if (this->rel_dyn_ != NULL) + if (this->rela_dyn_ != NULL) { - const Output_data* od = this->rel_dyn_; + const Output_data* od = this->rela_dyn_; odyn->add_section_address(elfcpp::DT_RELA, od); odyn->add_section_size(elfcpp::DT_RELASZ, od); odyn->add_constant(elfcpp::DT_RELAENT, @@ -1023,8 +1059,8 @@ Target_x86_64::do_finalize_sections(Layout* layout) return; if (this->copy_relocs_->any_to_emit()) { - Reloc_section* rel_dyn = this->rel_dyn_section(layout); - this->copy_relocs_->emit(rel_dyn); + Reloc_section* rela_dyn = this->rela_dyn_section(layout); + this->copy_relocs_->emit(rela_dyn); } delete this->copy_relocs_; this->copy_relocs_ = NULL; @@ -1036,7 +1072,7 @@ 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, + const elfcpp::Rela<64, false>& rela, unsigned int r_type, const Sized_symbol<64>* gsym, const Symbol_value<64>* psymval, @@ -1048,11 +1084,11 @@ Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, { if (r_type != elfcpp::R_X86_64_PLT32 || gsym == NULL - || strcmp(gsym->name(), "___tls_get_addr") != 0) + || 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()); + relinfo->location(relnum, rela.get_r_offset()).c_str()); gold_exit(false); } @@ -1071,7 +1107,35 @@ Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, } const Sized_relobj<64, false>* object = relinfo->object; - const elfcpp::Elf_Xword addend = rel.get_r_addend(); + const elfcpp::Elf_Xword addend = rela.get_r_addend(); + + // Get the GOT offset if needed. + bool have_got_offset = false; + unsigned int got_offset = 0; + switch (r_type) + { + case elfcpp::R_X86_64_GOT32: + case elfcpp::R_X86_64_GOT64: + case elfcpp::R_X86_64_GOTPLT64: + case elfcpp::R_X86_64_GOTPCREL: + case elfcpp::R_X86_64_GOTPCREL64: + if (gsym != NULL) + { + gold_assert(gsym->has_got_offset()); + got_offset = gsym->got_offset(); + } + else + { + unsigned int r_sym = elfcpp::elf_r_sym<64>(rela.get_r_info()); + got_offset = object->local_got_offset(r_sym); + } + have_got_offset = true; + break; + + default: + break; + } + switch (r_type) { @@ -1135,10 +1199,8 @@ Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, 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); + gold_assert(have_got_offset); + Relocate_functions<64, false>::rela32(view, got_offset, addend); break; case elfcpp::R_X86_64_GOTPC32: @@ -1154,10 +1216,8 @@ Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, // The ABI doc says "Like GOT64, but indicates a PLT entry is needed." // Since we always add a PLT entry, this is equivalent. case elfcpp::R_X86_64_GOTPLT64: // TODO(csilvers): correct? - // Local GOT offsets not yet supported. - gold_assert(gsym); - gold_assert(gsym->has_got_offset()); - Relocate_functions<64, false>::rela64(view, gsym->got_offset(), addend); + gold_assert(have_got_offset); + Relocate_functions<64, false>::rela64(view, got_offset, addend); break; case elfcpp::R_X86_64_GOTPC64: @@ -1180,25 +1240,19 @@ Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, case elfcpp::R_X86_64_GOTPCREL: { - // Local GOT offsets not yet supported. - gold_assert(gsym); - gold_assert(gsym->has_got_offset()); - elfcpp::Elf_types<64>::Elf_Addr value; - value = (target->got_section(NULL, NULL)->address() - + gsym->got_offset()); - Relocate_functions<64, false>::pcrela32(view, value, addend, address); + gold_assert(have_got_offset); + elfcpp::Elf_types<64>::Elf_Addr value; + value = target->got_section(NULL, NULL)->address() + got_offset; + Relocate_functions<64, false>::pcrela32(view, value, addend, address); } break; case elfcpp::R_X86_64_GOTPCREL64: { - // Local GOT offsets not yet supported. - gold_assert(gsym); - gold_assert(gsym->has_got_offset()); - elfcpp::Elf_types<64>::Elf_Addr value; - value = (target->got_section(NULL, NULL)->address() - + gsym->got_offset()); - Relocate_functions<64, false>::pcrela64(view, value, addend, address); + gold_assert(have_got_offset); + elfcpp::Elf_types<64>::Elf_Addr value; + value = target->got_section(NULL, NULL)->address() + got_offset; + Relocate_functions<64, false>::pcrela64(view, value, addend, address); } break; @@ -1209,12 +1263,10 @@ Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, // These are outstanding tls relocs, which are unexpected when linking case elfcpp::R_X86_64_TPOFF64: 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(), + relinfo->location(relnum, rela.get_r_offset()).c_str(), r_type); gold_exit(false); break; @@ -1226,7 +1278,9 @@ Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, case elfcpp::R_X86_64_TPOFF32: // TODO(csilvers): correct? case elfcpp::R_X86_64_GOTPC32_TLSDESC: // TODO(csilvers): correct? case elfcpp::R_X86_64_TLSDESC_CALL: // TODO(csilvers): correct? - this->relocate_tls(relinfo, relnum, rel, r_type, gsym, psymval, view, + case elfcpp::R_X86_64_DTPOFF32: + case elfcpp::R_X86_64_DTPOFF64: + this->relocate_tls(relinfo, relnum, rela, r_type, gsym, psymval, view, address, view_size); break; @@ -1236,7 +1290,7 @@ Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo, default: fprintf(stderr, _("%s: %s: unsupported reloc %u\n"), program_name, - relinfo->location(relnum, rel.get_r_offset()).c_str(), + relinfo->location(relnum, rela.get_r_offset()).c_str(), r_type); gold_exit(false); break; @@ -1318,6 +1372,22 @@ Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>* relinfo, r_type); gold_exit(false); break; + + case elfcpp::R_X86_64_DTPOFF32: + if (opt_r_type == elfcpp::R_X86_64_TPOFF32) + value = value - (tls_segment->vaddr() + tls_segment->memsz()); + else + value = value - tls_segment->vaddr(); + Relocate_functions<64, false>::rel32(view, value); + break; + + case elfcpp::R_X86_64_DTPOFF64: + if (opt_r_type == elfcpp::R_X86_64_TPOFF64) + value = value - (tls_segment->vaddr() + tls_segment->memsz()); + else + value = value - tls_segment->vaddr(); + Relocate_functions<64, false>::rel64(view, value); + break; } } @@ -1335,50 +1405,47 @@ Target_x86_64::Relocate::tls_ie_to_le(const Relocate_info<64, false>* relinfo, unsigned char* view, off_t view_size) { - // We have to actually change the instructions, which means that we - // need to examine the opcodes to figure out which instruction we + // We need to examine the opcodes to figure out which instruction we // are looking at. - // 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); + // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg + // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg + + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -3); Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 4); - unsigned char op1 = view[-1]; - if (op1 == 0xa1) + unsigned char op1 = view[-3]; + unsigned char op2 = view[-2]; + unsigned char op3 = view[-1]; + unsigned char reg = op3 >> 3; + + if (op2 == 0x8b) + { + // movq + if (op1 == 0x4c) + view[-3] = 0x49; + view[-2] = 0xc7; + view[-1] = 0xc0 | reg; + } + else if (reg == 4) { - // movl XX,%eax ==> movl $YY,%eax - view[-1] = 0xb8; + // Special handling for %rsp. + if (op1 == 0x4c) + view[-3] = 0x49; + view[-2] = 0x81; + view[-1] = 0xc0 | reg; } 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); + // addq + if (op1 == 0x4c) + view[-3] = 0x4d; + view[-2] = 0x8d; + view[-1] = 0x80 | reg | (reg << 3); } value = value - (tls_segment->vaddr() + tls_segment->memsz()); - Relocate_functions<64, false>::rel32(view, value); + Relocate_functions<64, false>::rela32(view, value, 0); } // Do a relocation in which we convert a TLS Global-Dynamic to a @@ -1395,54 +1462,24 @@ Target_x86_64::Relocate::tls_gd_to_le(const Relocate_info<64, false>* relinfo, unsigned char* view, off_t view_size) { - // 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); + // .byte 0x66; leaq foo@tlsgd(%rip),%rdi; + // .word 0x6666; rex64; call __tls_get_addr + // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax - unsigned char op1 = view[-1]; - unsigned char op2 = view[-2]; + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -4); + Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 12); Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, - op2 == 0x8d || op2 == 0x04); + (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) + == 0)); Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, - view[4] == 0xe8); + (memcmp(view + 4, "\x66\x66\x48\xe8", 4) + == 0)); - int roff = 5; + memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0", 16); - 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 (static_cast<off_t>(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>::rel32(view + roff, value); + value = value - (tls_segment->vaddr() + tls_segment->memsz()); + Relocate_functions<64, false>::rela32(view + 8, value, 0); // The next reloc should be a PLT32 reloc against __tls_get_addr. // We can skip it. |