diff options
Diffstat (limited to 'gold/arm.cc')
| -rw-r--r-- | gold/arm.cc | 431 |
1 files changed, 424 insertions, 7 deletions
diff --git a/gold/arm.cc b/gold/arm.cc index d974b1b..6348470 100644 --- a/gold/arm.cc +++ b/gold/arm.cc @@ -81,6 +81,9 @@ template<bool big_endian> class Arm_relobj; template<bool big_endian> +class Arm_relocate_functions; + +template<bool big_endian> class Target_arm; // For convenience. @@ -1847,11 +1850,12 @@ class Target_arm : public Sized_target<32, big_endian> 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), 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_() + 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_() { } // Whether we can use BLX. @@ -2301,6 +2305,16 @@ class Target_arm : public Sized_target<32, big_endian> 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, @@ -2312,6 +2326,11 @@ class Target_arm : public Sized_target<32, big_endian> 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. Output_data_got<32, big_endian>* got_section(Symbol_table*, Layout*); @@ -2328,6 +2347,15 @@ class Target_arm : public Sized_target<32, big_endian> 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 @@ -2340,6 +2368,10 @@ class Target_arm : public Sized_target<32, big_endian> 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. @@ -2454,7 +2486,11 @@ class Target_arm : public Sized_target<32, big_endian> // The types of GOT entries needed for this platform. enum Got_type { - GOT_TYPE_STANDARD = 0 // GOT entry for a regular symbol + 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; @@ -2481,6 +2517,10 @@ class Target_arm : public Sized_target<32, big_endian> 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. @@ -6673,6 +6713,79 @@ Target_arm<big_endian>::make_plt_entry(Symbol_table* symtab, Layout* layout, 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); + Reloc_section* rel_dyn = this->rel_dyn_section(layout); + Output_data_got<32, big_endian>* got = this->got_section(symtab, layout); + unsigned int got_offset = got->add_constant(0); + rel_dyn->add_local(object, 0, elfcpp::R_ARM_TLS_DTPMOD32, got, + got_offset); + 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> @@ -6929,6 +7042,97 @@ Target_arm<big_endian>::Scan::local(Symbol_table* symtab, 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. + 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()); + 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); + else + 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 + // 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. + 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()); + got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET, + target->rel_dyn_section(layout), + elfcpp::R_ARM_TLS_TPOFF32); + } + 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; @@ -7185,6 +7389,84 @@ Target_arm<big_endian>::Scan::global(Symbol_table* symtab, 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. + Output_data_got<32, big_endian>* got + = target->got_section(symtab, layout); + 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 + // 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. + Output_data_got<32, big_endian>* got + = target->got_section(symtab, layout); + got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET, + target->rel_dyn_section(layout), + elfcpp::R_ARM_TLS_TPOFF32); + } + 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; @@ -7436,7 +7718,7 @@ Target_arm<big_endian>::Relocate::relocate( const Symbol_value<32>* psymval, unsigned char* view, Arm_address address, - section_size_type /* view_size */ ) + section_size_type view_size) { typedef Arm_relocate_functions<big_endian> Arm_relocate_functions; @@ -7584,6 +7866,10 @@ Target_arm<big_endian>::Relocate::relocate( switch(reloc_property->relative_address_base()) { 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; @@ -7887,6 +8173,18 @@ Target_arm<big_endian>::Relocate::relocate( relative_address_base); 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 + reloc_status = + this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval, + view, address, view_size); + break; + default: gold_unreachable(); } @@ -7916,6 +8214,125 @@ Target_arm<big_endian>::Relocate::relocate( return true; } +// Perform a TLS relocation. + +template<bool big_endian> +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, + section_size_type /*view_size*/ ) +{ + typedef Arm_relocate_functions<big_endian> ArmRelocFuncs; + Output_segment* tls_segment = relinfo->layout->tls_segment(); + + const Sized_relobj<32, big_endian>* object = relinfo->object; + + elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0); + + 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) + { + // Relocate the field with the offset of the pair of GOT + // entries. + Relocate_functions<32, big_endian>::rel32(view, got_offset); + return ArmRelocFuncs::STATUS_OKAY; + } + } + break; + + 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()); + Relocate_functions<32, big_endian>::rel32(view, got_offset); + return ArmRelocFuncs::STATUS_OKAY; + } + break; + + case elfcpp::R_ARM_TLS_LDO32: // Alternate local-dynamic + Relocate_functions<32, big_endian>::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(); + Relocate_functions<32, big_endian>::rel32(view, got_offset); + return ArmRelocFuncs::STATUS_OKAY; + } + break; + + 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); + value = tls_segment->memsz() - value; + Relocate_functions<32, false>::rel32(view, value); + } + return ArmRelocFuncs::STATUS_OKAY; + + default: + gold_unreachable(); + } + + gold_error_at_location(relinfo, relnum, rel.get_r_offset(), + _("unsupported reloc %u"), + r_type); + return ArmRelocFuncs::STATUS_BAD_RELOC; +} + // Relocate section data. template<bool big_endian> |