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Diffstat (limited to 'gold/i386.cc')
| -rw-r--r-- | gold/i386.cc | 2610 |
1 files changed, 0 insertions, 2610 deletions
diff --git a/gold/i386.cc b/gold/i386.cc deleted file mode 100644 index 54f123333b7..00000000000 --- a/gold/i386.cc +++ /dev/null @@ -1,2610 +0,0 @@ -// i386.cc -- i386 target support for gold. - -// Copyright 2006, 2007, 2008 Free Software Foundation, Inc. -// Written by Ian Lance Taylor <iant@google.com>. - -// 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 General Public License as published by -// the Free Software Foundation; either version 3 of the License, or -// (at your option) any later version. - -// 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 General Public License for more details. - -// You should have received a copy of the GNU 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 <cstring> - -#include "elfcpp.h" -#include "parameters.h" -#include "reloc.h" -#include "i386.h" -#include "object.h" -#include "symtab.h" -#include "layout.h" -#include "output.h" -#include "copy-relocs.h" -#include "target.h" -#include "target-reloc.h" -#include "target-select.h" -#include "tls.h" - -namespace -{ - -using namespace gold; - -class Output_data_plt_i386; - -// The i386 target class. -// TLS info comes from -// http://people.redhat.com/drepper/tls.pdf -// http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt - -class Target_i386 : public Sized_target<32, false> -{ - public: - typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section; - - Target_i386() - : Sized_target<32, false>(&i386_info), - got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL), - copy_relocs_(elfcpp::R_386_COPY), dynbss_(NULL), - got_mod_index_offset_(-1U), tls_base_symbol_defined_(false) - { } - - // Scan the relocations to look for symbol adjustments. - void - scan_relocs(const General_options& options, - Symbol_table* symtab, - Layout* layout, - Sized_relobj<32, false>* object, - unsigned int data_shndx, - unsigned int sh_type, - const unsigned char* prelocs, - size_t reloc_count, - Output_section* output_section, - bool needs_special_offset_handling, - size_t local_symbol_count, - const unsigned char* plocal_symbols); - - // Finalize the sections. - void - do_finalize_sections(Layout*); - - // Return the value to use for a dynamic which requires special - // treatment. - uint64_t - do_dynsym_value(const Symbol*) const; - - // Relocate a section. - void - relocate_section(const Relocate_info<32, false>*, - unsigned int sh_type, - const unsigned char* prelocs, - size_t reloc_count, - Output_section* output_section, - bool needs_special_offset_handling, - unsigned char* view, - elfcpp::Elf_types<32>::Elf_Addr view_address, - section_size_type view_size); - - // Scan the relocs during a relocatable link. - void - scan_relocatable_relocs(const General_options& options, - Symbol_table* symtab, - Layout* layout, - Sized_relobj<32, false>* object, - unsigned int data_shndx, - unsigned int sh_type, - const unsigned char* prelocs, - size_t reloc_count, - Output_section* output_section, - bool needs_special_offset_handling, - size_t local_symbol_count, - const unsigned char* plocal_symbols, - Relocatable_relocs*); - - // Relocate a section during a relocatable link. - void - relocate_for_relocatable(const Relocate_info<32, false>*, - unsigned int sh_type, - const unsigned char* prelocs, - size_t reloc_count, - Output_section* output_section, - off_t offset_in_output_section, - const Relocatable_relocs*, - unsigned char* view, - elfcpp::Elf_types<32>::Elf_Addr view_address, - section_size_type view_size, - unsigned char* reloc_view, - section_size_type reloc_view_size); - - // Return a string used to fill a code section with nops. - std::string - do_code_fill(section_size_type length) const; - - // Return whether SYM is defined by the ABI. - bool - do_is_defined_by_abi(Symbol* sym) const - { return strcmp(sym->name(), "___tls_get_addr") == 0; } - - // Return the size of the GOT section. - section_size_type - got_size() - { - gold_assert(this->got_ != NULL); - return this->got_->data_size(); - } - - private: - // The class which scans relocations. - struct Scan - { - inline void - local(const General_options& options, Symbol_table* symtab, - Layout* layout, Target_i386* target, - Sized_relobj<32, false>* object, - unsigned int data_shndx, - Output_section* output_section, - const elfcpp::Rel<32, false>& reloc, unsigned int r_type, - const elfcpp::Sym<32, false>& lsym); - - inline void - global(const General_options& options, Symbol_table* symtab, - Layout* layout, Target_i386* target, - Sized_relobj<32, false>* object, - unsigned int data_shndx, - Output_section* output_section, - const elfcpp::Rel<32, false>& reloc, unsigned int r_type, - Symbol* gsym); - - static void - unsupported_reloc_local(Sized_relobj<32, false>*, unsigned int r_type); - - static void - unsupported_reloc_global(Sized_relobj<32, false>*, unsigned int r_type, - Symbol*); - }; - - // The class which implements relocation. - class Relocate - { - public: - Relocate() - : skip_call_tls_get_addr_(false), - local_dynamic_type_(LOCAL_DYNAMIC_NONE) - { } - - ~Relocate() - { - if (this->skip_call_tls_get_addr_) - { - // FIXME: This needs to specify the location somehow. - gold_error(_("missing expected TLS relocation")); - } - } - - // Return whether the static relocation needs to be applied. - inline bool - should_apply_static_reloc(const Sized_symbol<32>* gsym, - int ref_flags, - bool is_32bit); - - // Do a relocation. Return false if the caller should not issue - // any warnings about this relocation. - inline bool - relocate(const Relocate_info<32, false>*, Target_i386*, size_t relnum, - const elfcpp::Rel<32, false>&, - unsigned int r_type, const Sized_symbol<32>*, - const Symbol_value<32>*, - unsigned char*, elfcpp::Elf_types<32>::Elf_Addr, - section_size_type); - - private: - // Do a TLS relocation. - inline void - relocate_tls(const Relocate_info<32, false>*, Target_i386* target, - size_t relnum, const elfcpp::Rel<32, false>&, - unsigned int r_type, const Sized_symbol<32>*, - const Symbol_value<32>*, - unsigned char*, elfcpp::Elf_types<32>::Elf_Addr, - section_size_type); - - // Do a TLS General-Dynamic to Initial-Exec transition. - inline void - tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum, - Output_segment* tls_segment, - const elfcpp::Rel<32, false>&, unsigned int r_type, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size); - - // Do a TLS General-Dynamic to Local-Exec transition. - inline void - tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum, - Output_segment* tls_segment, - const elfcpp::Rel<32, false>&, unsigned int r_type, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size); - - // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec - // transition. - inline void - tls_desc_gd_to_ie(const Relocate_info<32, false>*, size_t relnum, - Output_segment* tls_segment, - const elfcpp::Rel<32, false>&, unsigned int r_type, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size); - - // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec - // transition. - inline void - tls_desc_gd_to_le(const Relocate_info<32, false>*, size_t relnum, - Output_segment* tls_segment, - const elfcpp::Rel<32, false>&, unsigned int r_type, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size); - - // Do a TLS Local-Dynamic to Local-Exec transition. - inline void - tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum, - Output_segment* tls_segment, - const elfcpp::Rel<32, false>&, unsigned int r_type, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size); - - // Do a TLS Initial-Exec to Local-Exec transition. - static inline void - tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum, - Output_segment* tls_segment, - const elfcpp::Rel<32, false>&, unsigned int r_type, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size); - - // We need to keep track of which type of local dynamic relocation - // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly. - enum Local_dynamic_type - { - LOCAL_DYNAMIC_NONE, - LOCAL_DYNAMIC_SUN, - LOCAL_DYNAMIC_GNU - }; - - // 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_; - // The type of local dynamic relocation we have seen in the section - // being relocated, if any. - Local_dynamic_type local_dynamic_type_; - }; - - // A class which returns the size required for a relocation type, - // used while scanning relocs during a relocatable link. - class Relocatable_size_for_reloc - { - public: - unsigned int - get_size_for_reloc(unsigned int, Relobj*); - }; - - // Adjust TLS relocation type based on the options and whether this - // is a local symbol. - static tls::Tls_optimization - optimize_tls_reloc(bool is_final, int r_type); - - // Get the GOT section, creating it if necessary. - Output_data_got<32, false>* - got_section(Symbol_table*, Layout*); - - // Get the GOT PLT section. - Output_data_space* - got_plt_section() const - { - gold_assert(this->got_plt_ != NULL); - return this->got_plt_; - } - - // Create a PLT entry for a global symbol. - void - make_plt_entry(Symbol_table*, Layout*, Symbol*); - - // Define the _TLS_MODULE_BASE_ symbol at the end of 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, false>* object); - - // Get the PLT section. - const Output_data_plt_i386* - 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*); - - // Return true if the symbol may need a COPY relocation. - // References from an executable object to non-function symbols - // defined in a dynamic object may need a COPY relocation. - bool - may_need_copy_reloc(Symbol* gsym) - { - return (!parameters->options().shared() - && gsym->is_from_dynobj() - && gsym->type() != elfcpp::STT_FUNC); - } - - // Add a potential copy relocation. - void - copy_reloc(Symbol_table* symtab, Layout* layout, - Sized_relobj<32, false>* object, - unsigned int shndx, Output_section* output_section, - Symbol* sym, const elfcpp::Rel<32, false>& reloc) - { - this->copy_relocs_.copy_reloc(symtab, layout, - symtab->get_sized_symbol<32>(sym), - object, shndx, output_section, reloc, - this->rel_dyn_section(layout)); - } - - // Information about this specific target which we pass to the - // general Target structure. - static const Target::Target_info i386_info; - - // The types of GOT entries needed for this platform. - enum Got_type - { - GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol - GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset - GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset - GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair - GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair - }; - - // The GOT section. - Output_data_got<32, false>* got_; - // The PLT section. - Output_data_plt_i386* plt_; - // The GOT PLT section. - Output_data_space* got_plt_; - // The dynamic reloc section. - Reloc_section* rel_dyn_; - // Relocs saved to avoid a COPY reloc. - Copy_relocs<elfcpp::SHT_REL, 32, false> 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_; -}; - -const Target::Target_info Target_i386::i386_info = -{ - 32, // size - false, // is_big_endian - elfcpp::EM_386, // machine_code - false, // has_make_symbol - false, // has_resolve - true, // has_code_fill - true, // is_default_stack_executable - '\0', // wrap_char - "/usr/lib/libc.so.1", // dynamic_linker - 0x08048000, // default_text_segment_address - 0x1000, // abi_pagesize (overridable by -z max-page-size) - 0x1000 // common_pagesize (overridable by -z common-page-size) -}; - -// Get the GOT section, creating it if necessary. - -Output_data_got<32, false>* -Target_i386::got_section(Symbol_table* symtab, Layout* layout) -{ - if (this->got_ == NULL) - { - gold_assert(symtab != NULL && layout != NULL); - - this->got_ = new Output_data_got<32, false>(); - - Output_section* os; - os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, - (elfcpp::SHF_ALLOC - | elfcpp::SHF_WRITE), - this->got_); - os->set_is_relro(); - - // The old GNU linker creates a .got.plt section. We just - // create another set of data in the .got section. Note that we - // always create a PLT if we create a GOT, although the PLT - // might be empty. - this->got_plt_ = new Output_data_space(4, "** GOT PLT"); - os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, - (elfcpp::SHF_ALLOC - | elfcpp::SHF_WRITE), - this->got_plt_); - os->set_is_relro(); - - // The first three entries are reserved. - this->got_plt_->set_current_data_size(3 * 4); - - // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT. - symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL, - 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_i386::Reloc_section* -Target_i386::rel_dyn_section(Layout* layout) -{ - if (this->rel_dyn_ == NULL) - { - gold_assert(layout != NULL); - this->rel_dyn_ = new Reloc_section(parameters->options().combreloc()); - layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL, - elfcpp::SHF_ALLOC, this->rel_dyn_); - } - return this->rel_dyn_; -} - -// A class to handle the PLT data. - -class Output_data_plt_i386 : public Output_section_data -{ - public: - typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section; - - Output_data_plt_i386(Layout*, Output_data_space*); - - // Add an entry to the PLT. - void - add_entry(Symbol* gsym); - - // Return the .rel.plt section data. - const Reloc_section* - rel_plt() const - { return this->rel_; } - - protected: - void - do_adjust_output_section(Output_section* os); - - // Write to a map file. - void - do_print_to_mapfile(Mapfile* mapfile) const - { mapfile->print_output_data(this, _("** PLT")); } - - private: - // The size of an entry in the PLT. - static const int plt_entry_size = 16; - - // The first entry in the PLT for an executable. - static unsigned char exec_first_plt_entry[plt_entry_size]; - - // The first entry in the PLT for a shared object. - static unsigned char dyn_first_plt_entry[plt_entry_size]; - - // Other entries in the PLT for an executable. - static unsigned char exec_plt_entry[plt_entry_size]; - - // Other entries in the PLT for a shared object. - static unsigned char dyn_plt_entry[plt_entry_size]; - - // Set the final size. - void - set_final_data_size() - { 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_i386::Output_data_plt_i386(Layout* layout, - Output_data_space* got_plt) - : Output_section_data(4), got_plt_(got_plt), count_(0) -{ - this->rel_ = new Reloc_section(false); - layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL, - elfcpp::SHF_ALLOC, this->rel_); -} - -void -Output_data_plt_i386::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_i386::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_; - - section_offset_type got_offset = this->got_plt_->current_data_size(); - - // Every PLT entry needs a GOT entry which points back to the PLT - // entry (this will be changed by the dynamic linker, normally - // lazily when the function is called). - this->got_plt_->set_current_data_size(got_offset + 4); - - // Every PLT entry needs a reloc. - gsym->set_needs_dynsym_entry(); - this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_, - got_offset); - - // Note that we don't need to save the symbol. The contents of the - // PLT are independent of which symbols are used. The symbols only - // appear in the relocations. -} - -// The first entry in the PLT for an executable. - -unsigned char Output_data_plt_i386::exec_first_plt_entry[plt_entry_size] = -{ - 0xff, 0x35, // pushl 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 - 0, 0, 0, 0 // unused -}; - -// The first entry in the PLT for a shared object. - -unsigned char Output_data_plt_i386::dyn_first_plt_entry[plt_entry_size] = -{ - 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx) - 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx) - 0, 0, 0, 0 // unused -}; - -// Subsequent entries in the PLT for an executable. - -unsigned char Output_data_plt_i386::exec_plt_entry[plt_entry_size] = -{ - 0xff, 0x25, // jmp indirect - 0, 0, 0, 0, // replaced with address of symbol in .got - 0x68, // pushl immediate - 0, 0, 0, 0, // replaced with offset into relocation table - 0xe9, // jmp relative - 0, 0, 0, 0 // replaced with offset to start of .plt -}; - -// Subsequent entries in the PLT for a shared object. - -unsigned char Output_data_plt_i386::dyn_plt_entry[plt_entry_size] = -{ - 0xff, 0xa3, // jmp *offset(%ebx) - 0, 0, 0, 0, // replaced with offset of symbol in .got - 0x68, // pushl immediate - 0, 0, 0, 0, // replaced with offset into relocation table - 0xe9, // jmp 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 all specified by the i386 ELF -// Processor Supplement. - -void -Output_data_plt_i386::do_write(Output_file* of) -{ - const off_t offset = this->offset(); - const section_size_type oview_size = - convert_to_section_size_type(this->data_size()); - unsigned char* const oview = of->get_output_view(offset, oview_size); - - const off_t got_file_offset = this->got_plt_->offset(); - const section_size_type got_size = - convert_to_section_size_type(this->got_plt_->data_size()); - unsigned char* const got_view = of->get_output_view(got_file_offset, - got_size); - - unsigned char* pov = oview; - - elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address(); - elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address(); - - if (parameters->options().shared()) - memcpy(pov, dyn_first_plt_entry, plt_entry_size); - else - { - memcpy(pov, exec_first_plt_entry, plt_entry_size); - elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4); - elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8); - } - pov += plt_entry_size; - - unsigned char* got_pov = got_view; - - memset(got_pov, 0, 12); - got_pov += 12; - - const int rel_size = elfcpp::Elf_sizes<32>::rel_size; - - unsigned int plt_offset = plt_entry_size; - unsigned int plt_rel_offset = 0; - unsigned int got_offset = 12; - const unsigned int count = this->count_; - for (unsigned int i = 0; - i < count; - ++i, - pov += plt_entry_size, - got_pov += 4, - plt_offset += plt_entry_size, - plt_rel_offset += rel_size, - got_offset += 4) - { - // Set and adjust the PLT entry itself. - - if (parameters->options().shared()) - { - memcpy(pov, dyn_plt_entry, plt_entry_size); - elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset); - } - else - { - memcpy(pov, exec_plt_entry, plt_entry_size); - elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, - (got_address - + got_offset)); - } - - elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset); - elfcpp::Swap<32, false>::writeval(pov + 12, - - (plt_offset + plt_entry_size)); - - // Set the entry in the GOT. - elfcpp::Swap<32, false>::writeval(got_pov, plt_address + plt_offset + 6); - } - - gold_assert(static_cast<section_size_type>(pov - oview) == oview_size); - gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size); - - of->write_output_view(offset, oview_size, oview); - of->write_output_view(got_file_offset, got_size, got_view); -} - -// Create a PLT entry for a global symbol. - -void -Target_i386::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_i386(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); -} - -// Define the _TLS_MODULE_BASE_ symbol at the end of the TLS segment. - -void -Target_i386::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) - { - symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL, - tls_segment, 0, 0, - elfcpp::STT_TLS, - elfcpp::STB_LOCAL, - elfcpp::STV_HIDDEN, 0, - Symbol::SEGMENT_END, true); - } - this->tls_base_symbol_defined_ = true; -} - -// Create a GOT entry for the TLS module index. - -unsigned int -Target_i386::got_mod_index_entry(Symbol_table* symtab, Layout* layout, - Sized_relobj<32, false>* 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, false>* got = this->got_section(symtab, layout); - unsigned int got_offset = got->add_constant(0); - rel_dyn->add_local(object, 0, elfcpp::R_386_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. - -tls::Tls_optimization -Target_i386::optimize_tls_reloc(bool is_final, int r_type) -{ - // If we are generating a shared library, then we can't do anything - // in the linker. - if (parameters->options().shared()) - return tls::TLSOPT_NONE; - - switch (r_type) - { - case elfcpp::R_386_TLS_GD: - case elfcpp::R_386_TLS_GOTDESC: - case elfcpp::R_386_TLS_DESC_CALL: - // These are General-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 tls::TLSOPT_TO_LE; - return tls::TLSOPT_TO_IE; - - case elfcpp::R_386_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 tls::TLSOPT_TO_LE; - - case elfcpp::R_386_TLS_LDO_32: - // Another type of Local-Dynamic relocation. - return tls::TLSOPT_TO_LE; - - case elfcpp::R_386_TLS_IE: - case elfcpp::R_386_TLS_GOTIE: - case elfcpp::R_386_TLS_IE_32: - // 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 tls::TLSOPT_TO_LE; - return tls::TLSOPT_NONE; - - case elfcpp::R_386_TLS_LE: - case elfcpp::R_386_TLS_LE_32: - // When we already have Local-Exec, there is nothing further we - // can do. - return tls::TLSOPT_NONE; - - default: - gold_unreachable(); - } -} - -// Report an unsupported relocation against a local symbol. - -void -Target_i386::Scan::unsupported_reloc_local(Sized_relobj<32, false>* object, - unsigned int r_type) -{ - gold_error(_("%s: unsupported reloc %u against local symbol"), - object->name().c_str(), r_type); -} - -// Scan a relocation for a local symbol. - -inline void -Target_i386::Scan::local(const General_options&, - Symbol_table* symtab, - Layout* layout, - Target_i386* target, - Sized_relobj<32, false>* object, - unsigned int data_shndx, - Output_section* output_section, - const elfcpp::Rel<32, false>& reloc, - unsigned int r_type, - const elfcpp::Sym<32, false>& lsym) -{ - switch (r_type) - { - case elfcpp::R_386_NONE: - case elfcpp::R_386_GNU_VTINHERIT: - case elfcpp::R_386_GNU_VTENTRY: - break; - - case elfcpp::R_386_32: - // If building a shared library (or a position-independent - // executable), we need to create a dynamic relocation for - // this location. The relocation applied at link time will - // apply the link-time value, so we flag the location with - // an R_386_RELATIVE relocation so the dynamic loader can - // relocate it easily. - if (parameters->options().output_is_position_independent()) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); - rel_dyn->add_local_relative(object, r_sym, elfcpp::R_386_RELATIVE, - output_section, data_shndx, - reloc.get_r_offset()); - } - break; - - case elfcpp::R_386_16: - case elfcpp::R_386_8: - // If building a shared library (or a position-independent - // executable), we need to create a dynamic relocation for - // this location. Because the addend needs to remain in the - // data section, we need to be careful not to apply this - // relocation statically. - if (parameters->options().output_is_position_independent()) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); - if (lsym.get_st_type() != elfcpp::STT_SECTION) - rel_dyn->add_local(object, r_sym, r_type, output_section, - data_shndx, reloc.get_r_offset()); - else - { - gold_assert(lsym.get_st_value() == 0); - unsigned int shndx = lsym.get_st_shndx(); - bool is_ordinary; - shndx = object->adjust_sym_shndx(r_sym, shndx, - &is_ordinary); - if (!is_ordinary) - object->error(_("section symbol %u has bad shndx %u"), - r_sym, shndx); - else - rel_dyn->add_local_section(object, shndx, - r_type, output_section, - data_shndx, reloc.get_r_offset()); - } - } - break; - - case elfcpp::R_386_PC32: - case elfcpp::R_386_PC16: - case elfcpp::R_386_PC8: - break; - - case elfcpp::R_386_PLT32: - // Since we know this is a local symbol, we can handle this as a - // PC32 reloc. - break; - - case elfcpp::R_386_GOTOFF: - case elfcpp::R_386_GOTPC: - // We need a GOT section. - target->got_section(symtab, layout); - break; - - case elfcpp::R_386_GOT32: - { - // The symbol requires a GOT entry. - Output_data_got<32, false>* got = target->got_section(symtab, layout); - unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); - if (got->add_local(object, r_sym, GOT_TYPE_STANDARD)) - { - // If we are generating a shared object, we need to add a - // dynamic RELATIVE relocation for this symbol's GOT entry. - if (parameters->options().output_is_position_independent()) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); - rel_dyn->add_local_relative( - object, r_sym, elfcpp::R_386_RELATIVE, got, - object->local_got_offset(r_sym, GOT_TYPE_STANDARD)); - } - } - } - break; - - // These are relocations which should only be seen by the - // dynamic linker, and should never be seen here. - case elfcpp::R_386_COPY: - case elfcpp::R_386_GLOB_DAT: - case elfcpp::R_386_JUMP_SLOT: - case elfcpp::R_386_RELATIVE: - case elfcpp::R_386_TLS_TPOFF: - case elfcpp::R_386_TLS_DTPMOD32: - case elfcpp::R_386_TLS_DTPOFF32: - case elfcpp::R_386_TLS_TPOFF32: - case elfcpp::R_386_TLS_DESC: - gold_error(_("%s: unexpected reloc %u in object file"), - object->name().c_str(), r_type); - break; - - // These are initial TLS relocs, which are expected when - // linking. - case elfcpp::R_386_TLS_GD: // Global-dynamic - case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url) - case elfcpp::R_386_TLS_DESC_CALL: - case elfcpp::R_386_TLS_LDM: // Local-dynamic - case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic - case elfcpp::R_386_TLS_IE: // Initial-exec - case elfcpp::R_386_TLS_IE_32: - case elfcpp::R_386_TLS_GOTIE: - case elfcpp::R_386_TLS_LE: // Local-exec - case elfcpp::R_386_TLS_LE_32: - { - bool output_is_shared = parameters->options().shared(); - const tls::Tls_optimization optimized_type - = Target_i386::optimize_tls_reloc(!output_is_shared, r_type); - switch (r_type) - { - case elfcpp::R_386_TLS_GD: // 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, false>* 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_386_TLS_DTPMOD32, 0); - } - else if (optimized_type != tls::TLSOPT_TO_LE) - unsupported_reloc_local(object, r_type); - break; - - case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva) - target->define_tls_base_symbol(symtab, layout); - if (optimized_type == tls::TLSOPT_NONE) - { - // Create a double GOT entry with an R_386_TLS_DESC reloc. - Output_data_got<32, false>* 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_DESC, - target->rel_dyn_section(layout), - elfcpp::R_386_TLS_DESC, 0); - } - else if (optimized_type != tls::TLSOPT_TO_LE) - unsupported_reloc_local(object, r_type); - break; - - case elfcpp::R_386_TLS_DESC_CALL: - break; - - case elfcpp::R_386_TLS_LDM: // 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 if (optimized_type != tls::TLSOPT_TO_LE) - unsupported_reloc_local(object, r_type); - break; - - case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic - break; - - case elfcpp::R_386_TLS_IE: // Initial-exec - case elfcpp::R_386_TLS_IE_32: - case elfcpp::R_386_TLS_GOTIE: - layout->set_has_static_tls(); - if (optimized_type == tls::TLSOPT_NONE) - { - // For the R_386_TLS_IE relocation, we need to create a - // dynamic relocation when building a shared library. - if (r_type == elfcpp::R_386_TLS_IE - && parameters->options().shared()) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int r_sym - = elfcpp::elf_r_sym<32>(reloc.get_r_info()); - rel_dyn->add_local_relative(object, r_sym, - elfcpp::R_386_RELATIVE, - output_section, data_shndx, - reloc.get_r_offset()); - } - // Create a GOT entry for the tp-relative offset. - Output_data_got<32, false>* got - = target->got_section(symtab, layout); - unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); - unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32 - ? elfcpp::R_386_TLS_TPOFF32 - : elfcpp::R_386_TLS_TPOFF); - unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32 - ? GOT_TYPE_TLS_OFFSET - : GOT_TYPE_TLS_NOFFSET); - got->add_local_with_rel(object, r_sym, got_type, - target->rel_dyn_section(layout), - dyn_r_type); - } - else if (optimized_type != tls::TLSOPT_TO_LE) - unsupported_reloc_local(object, r_type); - break; - - case elfcpp::R_386_TLS_LE: // Local-exec - case elfcpp::R_386_TLS_LE_32: - 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()); - unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32 - ? elfcpp::R_386_TLS_TPOFF32 - : elfcpp::R_386_TLS_TPOFF); - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - rel_dyn->add_local(object, r_sym, dyn_r_type, output_section, - data_shndx, reloc.get_r_offset()); - } - break; - - default: - gold_unreachable(); - } - } - break; - - case elfcpp::R_386_32PLT: - case elfcpp::R_386_TLS_GD_32: - case elfcpp::R_386_TLS_GD_PUSH: - case elfcpp::R_386_TLS_GD_CALL: - case elfcpp::R_386_TLS_GD_POP: - case elfcpp::R_386_TLS_LDM_32: - case elfcpp::R_386_TLS_LDM_PUSH: - case elfcpp::R_386_TLS_LDM_CALL: - case elfcpp::R_386_TLS_LDM_POP: - case elfcpp::R_386_USED_BY_INTEL_200: - default: - unsupported_reloc_local(object, r_type); - break; - } -} - -// Report an unsupported relocation against a global symbol. - -void -Target_i386::Scan::unsupported_reloc_global(Sized_relobj<32, false>* object, - unsigned int r_type, - Symbol* gsym) -{ - gold_error(_("%s: unsupported reloc %u against global symbol %s"), - object->name().c_str(), r_type, gsym->demangled_name().c_str()); -} - -// Scan a relocation for a global symbol. - -inline void -Target_i386::Scan::global(const General_options&, - Symbol_table* symtab, - Layout* layout, - Target_i386* target, - Sized_relobj<32, false>* object, - unsigned int data_shndx, - Output_section* output_section, - const elfcpp::Rel<32, false>& reloc, - unsigned int r_type, - Symbol* gsym) -{ - switch (r_type) - { - case elfcpp::R_386_NONE: - case elfcpp::R_386_GNU_VTINHERIT: - case elfcpp::R_386_GNU_VTENTRY: - break; - - case elfcpp::R_386_32: - case elfcpp::R_386_16: - case elfcpp::R_386_8: - { - // Make a PLT entry if necessary. - if (gsym->needs_plt_entry()) - { - target->make_plt_entry(symtab, layout, gsym); - // Since this is not a PC-relative relocation, we may be - // taking the address of a function. In that case we need to - // set the entry in the dynamic symbol table to the address of - // the PLT entry. - if (gsym->is_from_dynobj() && !parameters->options().shared()) - gsym->set_needs_dynsym_value(); - } - // Make a dynamic relocation if necessary. - if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF)) - { - if (target->may_need_copy_reloc(gsym)) - { - target->copy_reloc(symtab, layout, object, - data_shndx, output_section, gsym, reloc); - } - else if (r_type == elfcpp::R_386_32 - && gsym->can_use_relative_reloc(false)) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE, - output_section, object, - data_shndx, reloc.get_r_offset()); - } - else - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - rel_dyn->add_global(gsym, r_type, output_section, object, - data_shndx, reloc.get_r_offset()); - } - } - } - break; - - case elfcpp::R_386_PC32: - case elfcpp::R_386_PC16: - case elfcpp::R_386_PC8: - { - // Make a PLT entry if necessary. - if (gsym->needs_plt_entry()) - { - // These relocations are used for function calls only in - // non-PIC code. For a 32-bit relocation in a shared library, - // we'll need a text relocation anyway, so we can skip the - // PLT entry and let the dynamic linker bind the call directly - // to the target. For smaller relocations, we should use a - // PLT entry to ensure that the call can reach. - if (!parameters->options().shared() - || r_type != elfcpp::R_386_PC32) - target->make_plt_entry(symtab, layout, gsym); - } - // Make a dynamic relocation if necessary. - int flags = Symbol::NON_PIC_REF; - if (gsym->type() == elfcpp::STT_FUNC) - flags |= Symbol::FUNCTION_CALL; - if (gsym->needs_dynamic_reloc(flags)) - { - if (target->may_need_copy_reloc(gsym)) - { - target->copy_reloc(symtab, layout, object, - data_shndx, output_section, gsym, reloc); - } - else - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - rel_dyn->add_global(gsym, r_type, output_section, object, - data_shndx, reloc.get_r_offset()); - } - } - } - break; - - case elfcpp::R_386_GOT32: - { - // The symbol requires a GOT entry. - Output_data_got<32, false>* got = target->got_section(symtab, layout); - if (gsym->final_value_is_known()) - got->add_global(gsym, GOT_TYPE_STANDARD); - else - { - // If this symbol is not fully resolved, we need to add a - // GOT entry with a dynamic relocation. - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - if (gsym->is_from_dynobj() - || gsym->is_undefined() - || gsym->is_preemptible()) - got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, - rel_dyn, elfcpp::R_386_GLOB_DAT); - else - { - if (got->add_global(gsym, GOT_TYPE_STANDARD)) - rel_dyn->add_global_relative( - gsym, elfcpp::R_386_RELATIVE, got, - gsym->got_offset(GOT_TYPE_STANDARD)); - } - } - } - break; - - case elfcpp::R_386_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; - // If building a shared library, we can also skip the PLT entry - // if the symbol is defined in the output file and is protected - // or hidden. - if (gsym->is_defined() - && !gsym->is_from_dynobj() - && !gsym->is_preemptible()) - break; - target->make_plt_entry(symtab, layout, gsym); - break; - - case elfcpp::R_386_GOTOFF: - case elfcpp::R_386_GOTPC: - // We need a GOT section. - target->got_section(symtab, layout); - break; - - // These are relocations which should only be seen by the - // dynamic linker, and should never be seen here. - case elfcpp::R_386_COPY: - case elfcpp::R_386_GLOB_DAT: - case elfcpp::R_386_JUMP_SLOT: - case elfcpp::R_386_RELATIVE: - case elfcpp::R_386_TLS_TPOFF: - case elfcpp::R_386_TLS_DTPMOD32: - case elfcpp::R_386_TLS_DTPOFF32: - case elfcpp::R_386_TLS_TPOFF32: - case elfcpp::R_386_TLS_DESC: - gold_error(_("%s: unexpected reloc %u in object file"), - object->name().c_str(), r_type); - break; - - // These are initial tls relocs, which are expected when - // linking. - case elfcpp::R_386_TLS_GD: // Global-dynamic - case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url) - case elfcpp::R_386_TLS_DESC_CALL: - case elfcpp::R_386_TLS_LDM: // Local-dynamic - case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic - case elfcpp::R_386_TLS_IE: // Initial-exec - case elfcpp::R_386_TLS_IE_32: - case elfcpp::R_386_TLS_GOTIE: - case elfcpp::R_386_TLS_LE: // Local-exec - case elfcpp::R_386_TLS_LE_32: - { - const bool is_final = gsym->final_value_is_known(); - const tls::Tls_optimization optimized_type - = Target_i386::optimize_tls_reloc(is_final, r_type); - switch (r_type) - { - case elfcpp::R_386_TLS_GD: // 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, false>* got - = target->got_section(symtab, layout); - got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR, - target->rel_dyn_section(layout), - elfcpp::R_386_TLS_DTPMOD32, - elfcpp::R_386_TLS_DTPOFF32); - } - else if (optimized_type == tls::TLSOPT_TO_IE) - { - // Create a GOT entry for the tp-relative offset. - Output_data_got<32, false>* got - = target->got_section(symtab, layout); - got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET, - target->rel_dyn_section(layout), - elfcpp::R_386_TLS_TPOFF); - } - else if (optimized_type != tls::TLSOPT_TO_LE) - unsupported_reloc_global(object, r_type, gsym); - break; - - case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (~oliva url) - target->define_tls_base_symbol(symtab, layout); - if (optimized_type == tls::TLSOPT_NONE) - { - // Create a double GOT entry with an R_386_TLS_DESC reloc. - Output_data_got<32, false>* got - = target->got_section(symtab, layout); - got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, - target->rel_dyn_section(layout), - elfcpp::R_386_TLS_DESC, 0); - } - else if (optimized_type == tls::TLSOPT_TO_IE) - { - // Create a GOT entry for the tp-relative offset. - Output_data_got<32, false>* got - = target->got_section(symtab, layout); - got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET, - target->rel_dyn_section(layout), - elfcpp::R_386_TLS_TPOFF); - } - else if (optimized_type != tls::TLSOPT_TO_LE) - unsupported_reloc_global(object, r_type, gsym); - break; - - case elfcpp::R_386_TLS_DESC_CALL: - break; - - case elfcpp::R_386_TLS_LDM: // 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 if (optimized_type != tls::TLSOPT_TO_LE) - unsupported_reloc_global(object, r_type, gsym); - break; - - case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic - break; - - case elfcpp::R_386_TLS_IE: // Initial-exec - case elfcpp::R_386_TLS_IE_32: - case elfcpp::R_386_TLS_GOTIE: - layout->set_has_static_tls(); - if (optimized_type == tls::TLSOPT_NONE) - { - // For the R_386_TLS_IE relocation, we need to create a - // dynamic relocation when building a shared library. - if (r_type == elfcpp::R_386_TLS_IE - && parameters->options().shared()) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE, - output_section, object, - data_shndx, - reloc.get_r_offset()); - } - // Create a GOT entry for the tp-relative offset. - Output_data_got<32, false>* got - = target->got_section(symtab, layout); - unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32 - ? elfcpp::R_386_TLS_TPOFF32 - : elfcpp::R_386_TLS_TPOFF); - unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32 - ? GOT_TYPE_TLS_OFFSET - : GOT_TYPE_TLS_NOFFSET); - got->add_global_with_rel(gsym, got_type, - target->rel_dyn_section(layout), - dyn_r_type); - } - else if (optimized_type != tls::TLSOPT_TO_LE) - unsupported_reloc_global(object, r_type, gsym); - break; - - case elfcpp::R_386_TLS_LE: // Local-exec - case elfcpp::R_386_TLS_LE_32: - layout->set_has_static_tls(); - if (parameters->options().shared()) - { - // We need to create a dynamic relocation. - unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32 - ? elfcpp::R_386_TLS_TPOFF32 - : elfcpp::R_386_TLS_TPOFF); - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - rel_dyn->add_global(gsym, dyn_r_type, output_section, object, - data_shndx, reloc.get_r_offset()); - } - break; - - default: - gold_unreachable(); - } - } - break; - - case elfcpp::R_386_32PLT: - case elfcpp::R_386_TLS_GD_32: - case elfcpp::R_386_TLS_GD_PUSH: - case elfcpp::R_386_TLS_GD_CALL: - case elfcpp::R_386_TLS_GD_POP: - case elfcpp::R_386_TLS_LDM_32: - case elfcpp::R_386_TLS_LDM_PUSH: - case elfcpp::R_386_TLS_LDM_CALL: - case elfcpp::R_386_TLS_LDM_POP: - case elfcpp::R_386_USED_BY_INTEL_200: - default: - unsupported_reloc_global(object, r_type, gsym); - break; - } -} - -// Scan relocations for a section. - -void -Target_i386::scan_relocs(const General_options& options, - Symbol_table* symtab, - Layout* layout, - Sized_relobj<32, false>* object, - unsigned int data_shndx, - unsigned int sh_type, - const unsigned char* prelocs, - size_t reloc_count, - Output_section* output_section, - bool needs_special_offset_handling, - size_t local_symbol_count, - const unsigned char* plocal_symbols) -{ - if (sh_type == elfcpp::SHT_RELA) - { - gold_error(_("%s: unsupported RELA reloc section"), - object->name().c_str()); - return; - } - - gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL, - Target_i386::Scan>( - options, - symtab, - layout, - this, - object, - data_shndx, - prelocs, - reloc_count, - output_section, - needs_special_offset_handling, - local_symbol_count, - plocal_symbols); -} - -// Finalize the sections. - -void -Target_i386::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_REL); - } - - if (this->rel_dyn_ != NULL) - { - const Output_data* od = this->rel_dyn_; - odyn->add_section_address(elfcpp::DT_REL, od); - odyn->add_section_size(elfcpp::DT_RELSZ, od); - odyn->add_constant(elfcpp::DT_RELENT, - elfcpp::Elf_sizes<32>::rel_size); - } - - if (!parameters->options().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_.any_saved_relocs()) - this->copy_relocs_.emit(this->rel_dyn_section(layout)); -} - -// Return whether a direct absolute static relocation needs to be applied. -// In cases where Scan::local() or Scan::global() has created -// a dynamic relocation other than R_386_RELATIVE, the addend -// of the relocation is carried in the data, and we must not -// apply the static relocation. - -inline bool -Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol<32>* gsym, - int ref_flags, - bool is_32bit) -{ - // For local symbols, we will have created a non-RELATIVE dynamic - // relocation only if (a) the output is position independent, - // (b) the relocation is absolute (not pc- or segment-relative), and - // (c) the relocation is not 32 bits wide. - if (gsym == NULL) - return !(parameters->options().output_is_position_independent() - && (ref_flags & Symbol::ABSOLUTE_REF) - && !is_32bit); - - // For global symbols, we use the same helper routines used in the - // scan pass. If we did not create a dynamic relocation, or if we - // created a RELATIVE dynamic relocation, we should apply the static - // relocation. - bool has_dyn = gsym->needs_dynamic_reloc(ref_flags); - bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF) - && gsym->can_use_relative_reloc(ref_flags - & Symbol::FUNCTION_CALL); - return !has_dyn || is_rel; -} - -// Perform a relocation. - -inline bool -Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo, - Target_i386* target, - size_t relnum, - const elfcpp::Rel<32, false>& rel, - unsigned int r_type, - const Sized_symbol<32>* gsym, - const Symbol_value<32>* psymval, - unsigned char* view, - elfcpp::Elf_types<32>::Elf_Addr address, - section_size_type view_size) -{ - if (this->skip_call_tls_get_addr_) - { - if (r_type != elfcpp::R_386_PLT32 - || gsym == NULL - || strcmp(gsym->name(), "___tls_get_addr") != 0) - gold_error_at_location(relinfo, relnum, rel.get_r_offset(), - _("missing expected TLS relocation")); - else - { - this->skip_call_tls_get_addr_ = false; - return false; - } - } - - // Pick the value to use for symbols defined in shared objects. - Symbol_value<32> symval; - if (gsym != NULL - && gsym->use_plt_offset(r_type == elfcpp::R_386_PC8 - || r_type == elfcpp::R_386_PC16 - || r_type == elfcpp::R_386_PC32)) - { - symval.set_output_value(target->plt_section()->address() - + gsym->plt_offset()); - psymval = &symval; - } - - const Sized_relobj<32, false>* object = relinfo->object; - - // Get the GOT offset if needed. - // The GOT pointer points to the end of the GOT section. - // We need to subtract the size of the GOT section to get - // the actual offset to use in the relocation. - bool have_got_offset = false; - unsigned int got_offset = 0; - switch (r_type) - { - case elfcpp::R_386_GOT32: - if (gsym != NULL) - { - gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD)); - got_offset = (gsym->got_offset(GOT_TYPE_STANDARD) - - target->got_size()); - } - else - { - unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info()); - gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD)); - got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD) - - target->got_size()); - } - have_got_offset = true; - break; - - default: - break; - } - - switch (r_type) - { - case elfcpp::R_386_NONE: - case elfcpp::R_386_GNU_VTINHERIT: - case elfcpp::R_386_GNU_VTENTRY: - break; - - case elfcpp::R_386_32: - if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true)) - Relocate_functions<32, false>::rel32(view, object, psymval); - break; - - case elfcpp::R_386_PC32: - { - int ref_flags = Symbol::NON_PIC_REF; - if (gsym != NULL && gsym->type() == elfcpp::STT_FUNC) - ref_flags |= Symbol::FUNCTION_CALL; - if (should_apply_static_reloc(gsym, ref_flags, true)) - Relocate_functions<32, false>::pcrel32(view, object, psymval, address); - } - break; - - case elfcpp::R_386_16: - if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false)) - Relocate_functions<32, false>::rel16(view, object, psymval); - break; - - case elfcpp::R_386_PC16: - { - int ref_flags = Symbol::NON_PIC_REF; - if (gsym != NULL && gsym->type() == elfcpp::STT_FUNC) - ref_flags |= Symbol::FUNCTION_CALL; - if (should_apply_static_reloc(gsym, ref_flags, false)) - Relocate_functions<32, false>::pcrel16(view, object, psymval, address); - } - break; - - case elfcpp::R_386_8: - if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false)) - Relocate_functions<32, false>::rel8(view, object, psymval); - break; - - case elfcpp::R_386_PC8: - { - int ref_flags = Symbol::NON_PIC_REF; - if (gsym != NULL && gsym->type() == elfcpp::STT_FUNC) - ref_flags |= Symbol::FUNCTION_CALL; - if (should_apply_static_reloc(gsym, ref_flags, false)) - Relocate_functions<32, false>::pcrel8(view, object, psymval, address); - } - break; - - case elfcpp::R_386_PLT32: - gold_assert(gsym == NULL - || gsym->has_plt_offset() - || gsym->final_value_is_known() - || (gsym->is_defined() - && !gsym->is_from_dynobj() - && !gsym->is_preemptible())); - Relocate_functions<32, false>::pcrel32(view, object, psymval, address); - break; - - case elfcpp::R_386_GOT32: - gold_assert(have_got_offset); - Relocate_functions<32, false>::rel32(view, got_offset); - break; - - case elfcpp::R_386_GOTOFF: - { - elfcpp::Elf_types<32>::Elf_Addr value; - value = (psymval->value(object, 0) - - target->got_plt_section()->address()); - Relocate_functions<32, false>::rel32(view, value); - } - break; - - case elfcpp::R_386_GOTPC: - { - elfcpp::Elf_types<32>::Elf_Addr value; - value = target->got_plt_section()->address(); - Relocate_functions<32, false>::pcrel32(view, value, address); - } - break; - - case elfcpp::R_386_COPY: - case elfcpp::R_386_GLOB_DAT: - case elfcpp::R_386_JUMP_SLOT: - case elfcpp::R_386_RELATIVE: - // These are outstanding tls relocs, which are unexpected when - // linking. - case elfcpp::R_386_TLS_TPOFF: - case elfcpp::R_386_TLS_DTPMOD32: - case elfcpp::R_386_TLS_DTPOFF32: - case elfcpp::R_386_TLS_TPOFF32: - case elfcpp::R_386_TLS_DESC: - gold_error_at_location(relinfo, relnum, rel.get_r_offset(), - _("unexpected reloc %u in object file"), - r_type); - break; - - // These are initial tls relocs, which are expected when - // linking. - case elfcpp::R_386_TLS_GD: // Global-dynamic - case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url) - case elfcpp::R_386_TLS_DESC_CALL: - case elfcpp::R_386_TLS_LDM: // Local-dynamic - case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic - case elfcpp::R_386_TLS_IE: // Initial-exec - case elfcpp::R_386_TLS_IE_32: - case elfcpp::R_386_TLS_GOTIE: - case elfcpp::R_386_TLS_LE: // Local-exec - case elfcpp::R_386_TLS_LE_32: - this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval, - view, address, view_size); - break; - - case elfcpp::R_386_32PLT: - case elfcpp::R_386_TLS_GD_32: - case elfcpp::R_386_TLS_GD_PUSH: - case elfcpp::R_386_TLS_GD_CALL: - case elfcpp::R_386_TLS_GD_POP: - case elfcpp::R_386_TLS_LDM_32: - case elfcpp::R_386_TLS_LDM_PUSH: - case elfcpp::R_386_TLS_LDM_CALL: - case elfcpp::R_386_TLS_LDM_POP: - case elfcpp::R_386_USED_BY_INTEL_200: - default: - gold_error_at_location(relinfo, relnum, rel.get_r_offset(), - _("unsupported reloc %u"), - r_type); - break; - } - - return true; -} - -// Perform a TLS relocation. - -inline void -Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo, - Target_i386* target, - size_t relnum, - const elfcpp::Rel<32, false>& 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) -{ - Output_segment* tls_segment = relinfo->layout->tls_segment(); - - const Sized_relobj<32, false>* object = relinfo->object; - - elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0); - - const bool is_final = - (gsym == NULL - ? !parameters->options().output_is_position_independent() - : gsym->final_value_is_known()); - const tls::Tls_optimization optimized_type - = Target_i386::optimize_tls_reloc(is_final, r_type); - switch (r_type) - { - case elfcpp::R_386_TLS_GD: // Global-dynamic - if (optimized_type == tls::TLSOPT_TO_LE) - { - gold_assert(tls_segment != NULL); - this->tls_gd_to_le(relinfo, relnum, tls_segment, - rel, r_type, value, view, - view_size); - break; - } - else - { - unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE - ? GOT_TYPE_TLS_NOFFSET - : 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_TO_IE) - { - gold_assert(tls_segment != NULL); - this->tls_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type, - got_offset, view, view_size); - break; - } - else if (optimized_type == tls::TLSOPT_NONE) - { - // Relocate the field with the offset of the pair of GOT - // entries. - Relocate_functions<32, false>::rel32(view, got_offset); - break; - } - } - gold_error_at_location(relinfo, relnum, rel.get_r_offset(), - _("unsupported reloc %u"), - r_type); - break; - - case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url) - case elfcpp::R_386_TLS_DESC_CALL: - this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU; - if (optimized_type == tls::TLSOPT_TO_LE) - { - gold_assert(tls_segment != NULL); - this->tls_desc_gd_to_le(relinfo, relnum, tls_segment, - rel, r_type, value, view, - view_size); - break; - } - else - { - unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE - ? GOT_TYPE_TLS_NOFFSET - : GOT_TYPE_TLS_DESC); - 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_TO_IE) - { - gold_assert(tls_segment != NULL); - this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type, - got_offset, view, view_size); - break; - } - else if (optimized_type == tls::TLSOPT_NONE) - { - if (r_type == elfcpp::R_386_TLS_GOTDESC) - { - // Relocate the field with the offset of the pair of GOT - // entries. - Relocate_functions<32, false>::rel32(view, got_offset); - } - break; - } - } - gold_error_at_location(relinfo, relnum, rel.get_r_offset(), - _("unsupported reloc %u"), - r_type); - break; - - case elfcpp::R_386_TLS_LDM: // Local-dynamic - if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN) - { - gold_error_at_location(relinfo, relnum, rel.get_r_offset(), - _("both SUN and GNU model " - "TLS relocations")); - break; - } - this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU; - if (optimized_type == tls::TLSOPT_TO_LE) - { - gold_assert(tls_segment != NULL); - this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type, - value, view, view_size); - break; - } - else 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, false>::rel32(view, got_offset); - break; - } - gold_error_at_location(relinfo, relnum, rel.get_r_offset(), - _("unsupported reloc %u"), - r_type); - break; - - case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic - // This reloc can appear in debugging sections, in which case we - // won't see the TLS_LDM reloc. The local_dynamic_type field - // tells us this. - if (optimized_type == tls::TLSOPT_TO_LE - && this->local_dynamic_type_ != LOCAL_DYNAMIC_NONE) - { - gold_assert(tls_segment != NULL); - value -= tls_segment->memsz(); - } - Relocate_functions<32, false>::rel32(view, value); - break; - - case elfcpp::R_386_TLS_IE: // Initial-exec - case elfcpp::R_386_TLS_GOTIE: - case elfcpp::R_386_TLS_IE_32: - if (optimized_type == tls::TLSOPT_TO_LE) - { - gold_assert(tls_segment != NULL); - Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment, - rel, r_type, value, view, - view_size); - break; - } - else 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 = (r_type == elfcpp::R_386_TLS_IE_32 - ? GOT_TYPE_TLS_OFFSET - : GOT_TYPE_TLS_NOFFSET); - 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); - } - // For the R_386_TLS_IE relocation, we need to apply the - // absolute address of the GOT entry. - if (r_type == elfcpp::R_386_TLS_IE) - got_offset += target->got_plt_section()->address(); - // All GOT offsets are relative to the end of the GOT. - got_offset -= target->got_size(); - Relocate_functions<32, false>::rel32(view, got_offset); - break; - } - gold_error_at_location(relinfo, relnum, rel.get_r_offset(), - _("unsupported reloc %u"), - r_type); - break; - - case elfcpp::R_386_TLS_LE: // 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(); - Relocate_functions<32, false>::rel32(view, value); - } - break; - - case elfcpp::R_386_TLS_LE_32: - // 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); - } - break; - } -} - -// Do a relocation in which we convert a TLS General-Dynamic to a -// Local-Exec. - -inline void -Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo, - size_t relnum, - Output_segment* tls_segment, - const elfcpp::Rel<32, false>& rel, - unsigned int, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type 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 - - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9); - - unsigned char op1 = view[-1]; - unsigned char op2 = view[-2]; - - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - op2 == 0x8d || op2 == 0x04); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8); - - int roff = 5; - - if (op2 == 0x04) - { - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - ((op1 & 0xc7) == 0x05 && op1 != (4 << 3))); - memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); - } - else - { - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - (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->memsz() - value; - Relocate_functions<32, false>::rel32(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; -} - -// Do a relocation in which we convert a TLS General-Dynamic to an -// Initial-Exec. - -inline void -Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo, - size_t relnum, - Output_segment*, - const elfcpp::Rel<32, false>& rel, - unsigned int, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size) -{ - // leal foo(,%ebx,1),%eax; call ___tls_get_addr - // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax - - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9); - - unsigned char op1 = view[-1]; - unsigned char op2 = view[-2]; - - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - op2 == 0x8d || op2 == 0x04); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8); - - int roff = 5; - - // FIXME: For now, support only the first (SIB) form. - tls::check_tls(relinfo, relnum, rel.get_r_offset(), op2 == 0x04); - - if (op2 == 0x04) - { - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - ((op1 & 0xc7) == 0x05 && op1 != (4 << 3))); - memcpy(view - 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12); - } - else - { - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - (op1 & 0xf8) == 0x80 && (op1 & 7) != 4); - if (rel.get_r_offset() + 9 < view_size - && view[9] == 0x90) - { - // FIXME: This is not the right instruction sequence. - // 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 - { - // FIXME: This is not the right instruction sequence. - // Use the five byte subl. - memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11); - } - } - - Relocate_functions<32, false>::rel32(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; -} - -// Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL -// General-Dynamic to a Local-Exec. - -inline void -Target_i386::Relocate::tls_desc_gd_to_le( - const Relocate_info<32, false>* relinfo, - size_t relnum, - Output_segment* tls_segment, - const elfcpp::Rel<32, false>& rel, - unsigned int r_type, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size) -{ - if (r_type == elfcpp::R_386_TLS_GOTDESC) - { - // leal foo@TLSDESC(%ebx), %eax - // ==> leal foo@NTPOFF, %eax - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - view[-2] == 0x8d && view[-1] == 0x83); - view[-1] = 0x05; - value -= tls_segment->memsz(); - Relocate_functions<32, false>::rel32(view, value); - } - else - { - // call *foo@TLSCALL(%eax) - // ==> nop; nop - gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL); - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - view[0] == 0xff && view[1] == 0x10); - view[0] = 0x66; - view[1] = 0x90; - } -} - -// Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL -// General-Dynamic to an Initial-Exec. - -inline void -Target_i386::Relocate::tls_desc_gd_to_ie( - const Relocate_info<32, false>* relinfo, - size_t relnum, - Output_segment*, - const elfcpp::Rel<32, false>& rel, - unsigned int r_type, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size) -{ - if (r_type == elfcpp::R_386_TLS_GOTDESC) - { - // leal foo@TLSDESC(%ebx), %eax - // ==> movl foo@GOTNTPOFF(%ebx), %eax - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - view[-2] == 0x8d && view[-1] == 0x83); - view[-2] = 0x8b; - Relocate_functions<32, false>::rel32(view, value); - } - else - { - // call *foo@TLSCALL(%eax) - // ==> nop; nop - gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL); - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2); - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - view[0] == 0xff && view[1] == 0x10); - view[0] = 0x66; - view[1] = 0x90; - } -} - -// Do a relocation in which we convert a TLS Local-Dynamic to a -// Local-Exec. - -inline void -Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo, - size_t relnum, - Output_segment*, - const elfcpp::Rel<32, false>& rel, - unsigned int, - elfcpp::Elf_types<32>::Elf_Addr, - unsigned char* view, - section_size_type view_size) -{ - // leal foo(%reg), %eax; call ___tls_get_addr - // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi - - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9); - - // FIXME: Does this test really always pass? - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - view[-2] == 0x8d && view[-1] == 0x83); - - tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8); - - memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11); - - // The next reloc should be a PLT32 reloc against __tls_get_addr. - // We can skip it. - this->skip_call_tls_get_addr_ = true; -} - -// Do a relocation in which we convert a TLS Initial-Exec to a -// Local-Exec. - -inline void -Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo, - size_t relnum, - Output_segment* tls_segment, - const elfcpp::Rel<32, false>& rel, - unsigned int r_type, - elfcpp::Elf_types<32>::Elf_Addr value, - unsigned char* view, - section_size_type view_size) -{ - // 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_386_TLS_IE) - { - // movl %gs:XX,%eax ==> movl $YY,%eax - // movl %gs:XX,%reg ==> movl $YY,%reg - // addl %gs:XX,%reg ==> addl $YY,%reg - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1); - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4); - - unsigned char op1 = view[-1]; - if (op1 == 0xa1) - { - // movl XX,%eax ==> movl $YY,%eax - view[-1] = 0xb8; - } - else - { - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); - - unsigned char op2 = view[-2]; - if (op2 == 0x8b) - { - // movl XX,%reg ==> movl $YY,%reg - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - (op1 & 0xc7) == 0x05); - view[-2] = 0xc7; - view[-1] = 0xc0 | ((op1 >> 3) & 7); - } - else if (op2 == 0x03) - { - // addl XX,%reg ==> addl $YY,%reg - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - (op1 & 0xc7) == 0x05); - view[-2] = 0x81; - view[-1] = 0xc0 | ((op1 >> 3) & 7); - } - else - tls::check_tls(relinfo, relnum, rel.get_r_offset(), 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 - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2); - tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4); - - unsigned char op1 = view[-1]; - unsigned char op2 = view[-2]; - tls::check_tls(relinfo, relnum, rel.get_r_offset(), - (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 - tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0); - } - - value = tls_segment->memsz() - value; - if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE) - value = - value; - - Relocate_functions<32, false>::rel32(view, value); -} - -// Relocate section data. - -void -Target_i386::relocate_section(const Relocate_info<32, false>* relinfo, - unsigned int sh_type, - const unsigned char* prelocs, - size_t reloc_count, - Output_section* output_section, - bool needs_special_offset_handling, - unsigned char* view, - elfcpp::Elf_types<32>::Elf_Addr address, - section_size_type view_size) -{ - gold_assert(sh_type == elfcpp::SHT_REL); - - gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL, - Target_i386::Relocate>( - relinfo, - this, - prelocs, - reloc_count, - output_section, - needs_special_offset_handling, - view, - address, - view_size); -} - -// Return the size of a relocation while scanning during a relocatable -// link. - -unsigned int -Target_i386::Relocatable_size_for_reloc::get_size_for_reloc( - unsigned int r_type, - Relobj* object) -{ - switch (r_type) - { - case elfcpp::R_386_NONE: - case elfcpp::R_386_GNU_VTINHERIT: - case elfcpp::R_386_GNU_VTENTRY: - case elfcpp::R_386_TLS_GD: // Global-dynamic - case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url) - case elfcpp::R_386_TLS_DESC_CALL: - case elfcpp::R_386_TLS_LDM: // Local-dynamic - case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic - case elfcpp::R_386_TLS_IE: // Initial-exec - case elfcpp::R_386_TLS_IE_32: - case elfcpp::R_386_TLS_GOTIE: - case elfcpp::R_386_TLS_LE: // Local-exec - case elfcpp::R_386_TLS_LE_32: - return 0; - - case elfcpp::R_386_32: - case elfcpp::R_386_PC32: - case elfcpp::R_386_GOT32: - case elfcpp::R_386_PLT32: - case elfcpp::R_386_GOTOFF: - case elfcpp::R_386_GOTPC: - return 4; - - case elfcpp::R_386_16: - case elfcpp::R_386_PC16: - return 2; - - case elfcpp::R_386_8: - case elfcpp::R_386_PC8: - return 1; - - // These are relocations which should only be seen by the - // dynamic linker, and should never be seen here. - case elfcpp::R_386_COPY: - case elfcpp::R_386_GLOB_DAT: - case elfcpp::R_386_JUMP_SLOT: - case elfcpp::R_386_RELATIVE: - case elfcpp::R_386_TLS_TPOFF: - case elfcpp::R_386_TLS_DTPMOD32: - case elfcpp::R_386_TLS_DTPOFF32: - case elfcpp::R_386_TLS_TPOFF32: - case elfcpp::R_386_TLS_DESC: - object->error(_("unexpected reloc %u in object file"), r_type); - return 0; - - case elfcpp::R_386_32PLT: - case elfcpp::R_386_TLS_GD_32: - case elfcpp::R_386_TLS_GD_PUSH: - case elfcpp::R_386_TLS_GD_CALL: - case elfcpp::R_386_TLS_GD_POP: - case elfcpp::R_386_TLS_LDM_32: - case elfcpp::R_386_TLS_LDM_PUSH: - case elfcpp::R_386_TLS_LDM_CALL: - case elfcpp::R_386_TLS_LDM_POP: - case elfcpp::R_386_USED_BY_INTEL_200: - default: - object->error(_("unsupported reloc %u in object file"), r_type); - return 0; - } -} - -// Scan the relocs during a relocatable link. - -void -Target_i386::scan_relocatable_relocs(const General_options& options, - Symbol_table* symtab, - Layout* layout, - Sized_relobj<32, false>* object, - unsigned int data_shndx, - unsigned int sh_type, - const unsigned char* prelocs, - size_t reloc_count, - Output_section* output_section, - bool needs_special_offset_handling, - size_t local_symbol_count, - const unsigned char* plocal_symbols, - Relocatable_relocs* rr) -{ - gold_assert(sh_type == elfcpp::SHT_REL); - - typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL, - Relocatable_size_for_reloc> Scan_relocatable_relocs; - - gold::scan_relocatable_relocs<32, false, elfcpp::SHT_REL, - Scan_relocatable_relocs>( - options, - symtab, - layout, - object, - data_shndx, - prelocs, - reloc_count, - output_section, - needs_special_offset_handling, - local_symbol_count, - plocal_symbols, - rr); -} - -// Relocate a section during a relocatable link. - -void -Target_i386::relocate_for_relocatable( - const Relocate_info<32, false>* relinfo, - unsigned int sh_type, - const unsigned char* prelocs, - size_t reloc_count, - Output_section* output_section, - off_t offset_in_output_section, - const Relocatable_relocs* rr, - unsigned char* view, - elfcpp::Elf_types<32>::Elf_Addr view_address, - section_size_type view_size, - unsigned char* reloc_view, - section_size_type reloc_view_size) -{ - gold_assert(sh_type == elfcpp::SHT_REL); - - gold::relocate_for_relocatable<32, false, elfcpp::SHT_REL>( - relinfo, - prelocs, - reloc_count, - output_section, - offset_in_output_section, - rr, - view, - view_address, - view_size, - reloc_view, - reloc_view_size); -} - -// Return the value to use for a dynamic which requires special -// treatment. This is how we support equality comparisons of function -// pointers across shared library boundaries, as described in the -// processor specific ABI supplement. - -uint64_t -Target_i386::do_dynsym_value(const Symbol* gsym) const -{ - gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset()); - return this->plt_section()->address() + gsym->plt_offset(); -} - -// Return a string used to fill a code section with nops to take up -// the specified length. - -std::string -Target_i386::do_code_fill(section_size_type length) const -{ - if (length >= 16) - { - // Build a jmp instruction to skip over the bytes. - unsigned char jmp[5]; - jmp[0] = 0xe9; - elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5); - return (std::string(reinterpret_cast<char*>(&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 i386 object files. - -class Target_selector_i386 : public Target_selector -{ -public: - Target_selector_i386() - : Target_selector(elfcpp::EM_386, 32, false, "elf32-i386") - { } - - Target* - do_instantiate_target() - { return new Target_i386(); } -}; - -Target_selector_i386 target_selector_i386; - -} // End anonymous namespace. |