--- /dev/null
+// x86_64.cc -- x86_64 target support for gold.
+
+// Copyright 2006, 2007, 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 Library General Public License
+// as published by the Free Software Foundation; either version 2, or
+// (at your option) any later version.
+
+// In addition to the permissions in the GNU Library General Public
+// License, the Free Software Foundation gives you unlimited
+// permission to link the compiled version of this file into
+// combinations with other programs, and to distribute those
+// combinations without any restriction coming from the use of this
+// file. (The Library Public License restrictions do apply in other
+// respects; for example, they cover modification of the file, and
+/// distribution when not linked into a combined executable.)
+
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// Library General Public License for more details.
+
+// You should have received a copy of the GNU Library General Public
+// License along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
+// 02110-1301, USA.
+
+#include "gold.h"
+
+#include <cstring>
+
+#include "elfcpp.h"
+#include "parameters.h"
+#include "reloc.h"
+#include "x86_64.h"
+#include "object.h"
+#include "symtab.h"
+#include "layout.h"
+#include "output.h"
+#include "target.h"
+#include "target-reloc.h"
+#include "target-select.h"
+
+namespace
+{
+
+using namespace gold;
+
+class Output_data_plt_x86_64;
+
+// The x86_64 target class.
+// See the ABI at http://www.x86-64.org/documentation/abi.pdf
+
+class Target_x86_64 : public Sized_target<64, false>
+{
+ public:
+ // In the x86_64 ABI, it says "The AMD64 ABI architectures uses only
+ // Elf64_Rela relocation entries with explicit addends."
+ typedef Output_data_reloc<elfcpp::SHT_RELA, true, 64, false> Reloc_section;
+
+ Target_x86_64()
+ : Sized_target<64, false>(&x86_64_info),
+ got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
+ copy_relocs_(NULL), dynbss_(NULL)
+ { }
+
+ // Scan the relocations to look for symbol adjustments.
+ void
+ scan_relocs(const General_options& options,
+ Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<64, false>* object,
+ unsigned int data_shndx,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ size_t local_symbol_count,
+ const unsigned char* plocal_symbols,
+ Symbol** global_symbols);
+
+ // Finalize the sections.
+ void
+ do_finalize_sections(Layout*);
+
+ // Relocate a section.
+ void
+ relocate_section(const Relocate_info<64, false>*,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ unsigned char* view,
+ elfcpp::Elf_types<64>::Elf_Addr view_address,
+ off_t view_size);
+
+ // Return a string used to fill a code section with nops.
+ std::string
+ do_code_fill(off_t length);
+
+ private:
+ // The class which scans relocations.
+ struct Scan
+ {
+ inline void
+ local(const General_options& options, Symbol_table* symtab,
+ Layout* layout, Target_x86_64* target,
+ Sized_relobj<64, false>* object,
+ unsigned int data_shndx,
+ const elfcpp::Rela<64, false>& reloc, unsigned int r_type,
+ const elfcpp::Sym<64, false>& lsym);
+
+ inline void
+ global(const General_options& options, Symbol_table* symtab,
+ Layout* layout, Target_x86_64* target,
+ Sized_relobj<64, false>* object,
+ unsigned int data_shndx,
+ const elfcpp::Rela<64, false>& reloc, unsigned int r_type,
+ Symbol* gsym);
+ };
+
+ // The class which implements relocation.
+ class Relocate
+ {
+ public:
+ Relocate()
+ : skip_call_tls_get_addr_(false)
+ { }
+
+ ~Relocate()
+ {
+ if (this->skip_call_tls_get_addr_)
+ {
+ // FIXME: This needs to specify the location somehow.
+ fprintf(stderr, _("%s: missing expected TLS relocation\n"),
+ program_name);
+ gold_exit(false);
+ }
+ }
+
+ // Do a relocation. Return false if the caller should not issue
+ // any warnings about this relocation.
+ inline bool
+ relocate(const Relocate_info<64, false>*, Target_x86_64*, size_t relnum,
+ const elfcpp::Rela<64, false>&,
+ unsigned int r_type, const Sized_symbol<64>*,
+ const Symbol_value<64>*,
+ unsigned char*, elfcpp::Elf_types<64>::Elf_Addr,
+ off_t);
+
+ private:
+ // Do a TLS relocation.
+ inline void
+ relocate_tls(const Relocate_info<64, false>*, size_t relnum,
+ const elfcpp::Rela<64, false>&,
+ unsigned int r_type, const Sized_symbol<64>*,
+ const Symbol_value<64>*,
+ unsigned char*, elfcpp::Elf_types<64>::Elf_Addr, off_t);
+
+ // Do a TLS Initial-Exec to Local-Exec transition.
+ static inline void
+ tls_ie_to_le(const Relocate_info<64, false>*, size_t relnum,
+ Output_segment* tls_segment,
+ const elfcpp::Rela<64, false>&, unsigned int r_type,
+ elfcpp::Elf_types<64>::Elf_Addr value,
+ unsigned char* view,
+ off_t view_size);
+
+ // Do a TLS Global-Dynamic to Local-Exec transition.
+ inline void
+ tls_gd_to_le(const Relocate_info<64, false>*, size_t relnum,
+ Output_segment* tls_segment,
+ const elfcpp::Rela<64, false>&, unsigned int r_type,
+ elfcpp::Elf_types<64>::Elf_Addr value,
+ unsigned char* view,
+ off_t view_size);
+
+ // Check the range for a TLS relocation.
+ static inline void
+ check_range(const Relocate_info<64, false>*, size_t relnum,
+ const elfcpp::Rela<64, false>&, off_t, off_t);
+
+ // Check the validity of a TLS relocation. This is like assert.
+ static inline void
+ check_tls(const Relocate_info<64, false>*, size_t relnum,
+ const elfcpp::Rela<64, false>&, bool);
+
+ // This is set if we should skip the next reloc, which should be a
+ // PLT32 reloc against ___tls_get_addr.
+ bool skip_call_tls_get_addr_;
+ };
+
+ // Adjust TLS relocation type based on the options and whether this
+ // is a local symbol.
+ static unsigned int
+ optimize_tls_reloc(bool is_final, int r_type);
+
+ // Get the GOT section, creating it if necessary.
+ Output_data_got<64, false>*
+ got_section(Symbol_table*, Layout*);
+
+ // Create a PLT entry for a global symbol.
+ void
+ make_plt_entry(Symbol_table*, Layout*, Symbol*);
+
+ // Get the PLT section.
+ Output_data_plt_x86_64*
+ plt_section() const
+ {
+ gold_assert(this->plt_ != NULL);
+ return this->plt_;
+ }
+
+ // Get the dynamic reloc section, creating it if necessary.
+ Reloc_section*
+ rel_dyn_section(Layout*);
+
+ // Copy a relocation against a global symbol.
+ void
+ copy_reloc(const General_options*, Symbol_table*, Layout*,
+ Sized_relobj<64, false>*, unsigned int,
+ Symbol*, const elfcpp::Rela<64, false>&);
+
+ // Information about this specific target which we pass to the
+ // general Target structure.
+ static const Target::Target_info x86_64_info;
+
+ // The GOT section.
+ Output_data_got<64, false>* got_;
+ // The PLT section.
+ Output_data_plt_x86_64* plt_;
+ // The GOT PLT section.
+ Output_data_space* got_plt_;
+ // The dynamic reloc section.
+ Reloc_section* rel_dyn_;
+ // Relocs saved to avoid a COPY reloc.
+ Copy_relocs<64, false>* copy_relocs_;
+ // Space for variables copied with a COPY reloc.
+ Output_data_space* dynbss_;
+};
+
+const Target::Target_info Target_x86_64::x86_64_info =
+{
+ 64, // size
+ false, // is_big_endian
+ elfcpp::EM_X86_64, // machine_code
+ false, // has_make_symbol
+ false, // has_resolve
+ true, // has_code_fill
+ "/lib/ld64.so.1", // program interpreter
+ 0x400000, // text_segment_address
+ 0x1000, // abi_pagesize
+ 0x1000 // common_pagesize
+};
+
+// Get the GOT section, creating it if necessary.
+
+Output_data_got<64, false>*
+Target_x86_64::got_section(Symbol_table* symtab, Layout* layout)
+{
+ if (this->got_ == NULL)
+ {
+ gold_assert(symtab != NULL && layout != NULL);
+
+ this->got_ = new Output_data_got<64, false>();
+
+ layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
+ elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
+ this->got_);
+
+ // The old GNU linker creates a .got.plt section. We just
+ // create another set of data in the .got section. Note that we
+ // always create a PLT if we create a GOT, although the PLT
+ // might be empty.
+ // TODO(csilvers): do we really need an alignment of 8?
+ this->got_plt_ = new Output_data_space(8);
+ layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
+ elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
+ this->got_plt_);
+
+ // The first three entries are reserved.
+ this->got_plt_->set_space_size(3 * 8);
+
+ // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
+ symtab->define_in_output_data(this, "_GLOBAL_OFFSET_TABLE_", NULL,
+ this->got_plt_,
+ 0, 0, elfcpp::STT_OBJECT,
+ elfcpp::STB_LOCAL,
+ elfcpp::STV_HIDDEN, 0,
+ false, false);
+ }
+
+ return this->got_;
+}
+
+// Get the dynamic reloc section, creating it if necessary.
+
+Target_x86_64::Reloc_section*
+Target_x86_64::rel_dyn_section(Layout* layout)
+{
+ if (this->rel_dyn_ == NULL)
+ {
+ gold_assert(layout != NULL);
+ this->rel_dyn_ = new Reloc_section();
+ layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
+ elfcpp::SHF_ALLOC, this->rel_dyn_);
+ }
+ return this->rel_dyn_;
+}
+
+// A class to handle the PLT data.
+
+class Output_data_plt_x86_64 : public Output_section_data
+{
+ public:
+ typedef Output_data_reloc<elfcpp::SHT_RELA, true, 64, false> Reloc_section;
+
+ Output_data_plt_x86_64(Layout*, Output_data_space*);
+
+ // Add an entry to the PLT.
+ void
+ add_entry(Symbol* gsym);
+
+ // Return the .rel.plt section data.
+ const Reloc_section*
+ rel_plt() const
+ { return this->rel_; }
+
+ protected:
+ void
+ do_adjust_output_section(Output_section* os);
+
+ private:
+ // The size of an entry in the PLT.
+ static const int plt_entry_size = 16;
+
+ // The first entry in the PLT.
+ // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
+ // procedure linkage table for both programs and shared objects."
+ static unsigned char first_plt_entry[plt_entry_size];
+
+ // Other entries in the PLT for an executable.
+ static unsigned char plt_entry[plt_entry_size];
+
+ // Set the final size.
+ void
+ do_set_address(uint64_t, off_t)
+ { this->set_data_size((this->count_ + 1) * plt_entry_size); }
+
+ // Write out the PLT data.
+ void
+ do_write(Output_file*);
+
+ // The reloc section.
+ Reloc_section* rel_;
+ // The .got.plt section.
+ Output_data_space* got_plt_;
+ // The number of PLT entries.
+ unsigned int count_;
+};
+
+// Create the PLT section. The ordinary .got section is an argument,
+// since we need to refer to the start. We also create our own .got
+// section just for PLT entries.
+
+Output_data_plt_x86_64::Output_data_plt_x86_64(Layout* layout,
+ Output_data_space* got_plt)
+ // TODO(csilvers): do we really need an alignment of 8?
+ : Output_section_data(8), got_plt_(got_plt), count_(0)
+{
+ this->rel_ = new Reloc_section();
+ layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
+ elfcpp::SHF_ALLOC, this->rel_);
+}
+
+void
+Output_data_plt_x86_64::do_adjust_output_section(Output_section* os)
+{
+ // UnixWare sets the entsize of .plt to 4, and so does the old GNU
+ // linker, and so do we.
+ os->set_entsize(4);
+}
+
+// Add an entry to the PLT.
+
+void
+Output_data_plt_x86_64::add_entry(Symbol* gsym)
+{
+ gold_assert(!gsym->has_plt_offset());
+
+ // Note that when setting the PLT offset we skip the initial
+ // reserved PLT entry.
+ gsym->set_plt_offset((this->count_ + 1) * plt_entry_size);
+
+ ++this->count_;
+
+ off_t got_offset = this->got_plt_->data_size();
+
+ // Every PLT entry needs a GOT entry which points back to the PLT
+ // entry (this will be changed by the dynamic linker, normally
+ // lazily when the function is called).
+ this->got_plt_->set_space_size(got_offset + 8);
+
+ // Every PLT entry needs a reloc.
+ gsym->set_needs_dynsym_entry();
+ this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_,
+ got_offset, 0);
+
+ // Note that we don't need to save the symbol. The contents of the
+ // PLT are independent of which symbols are used. The symbols only
+ // appear in the relocations.
+}
+
+// The first entry in the PLT for an executable.
+
+unsigned char Output_data_plt_x86_64::first_plt_entry[plt_entry_size] =
+{
+ // From AMD64 ABI Draft 0.98, page 76
+ 0xff, 0x35, // pushq contents of memory address
+ 0, 0, 0, 0, // replaced with address of .got + 4
+ 0xff, 0x25, // jmp indirect
+ 0, 0, 0, 0, // replaced with address of .got + 8
+ 0x90, 0x90, 0x90, 0x90 // noop (x4)
+};
+
+// Subsequent entries in the PLT for an executable.
+
+unsigned char Output_data_plt_x86_64::plt_entry[plt_entry_size] =
+{
+ // From AMD64 ABI Draft 0.98, page 76
+ 0xff, 0x25, // jmpq indirect
+ 0, 0, 0, 0, // replaced with address of symbol in .got
+ 0x68, // pushq immediate
+ 0, 0, 0, 0, // replaced with offset into relocation table
+ 0xe9, // jmpq relative
+ 0, 0, 0, 0 // replaced with offset to start of .plt
+};
+
+// Write out the PLT. This uses the hand-coded instructions above,
+// and adjusts them as needed. This is specified by the AMD64 ABI.
+
+void
+Output_data_plt_x86_64::do_write(Output_file* of)
+{
+ const off_t offset = this->offset();
+ const off_t oview_size = this->data_size();
+ unsigned char* const oview = of->get_output_view(offset, oview_size);
+
+ const off_t got_file_offset = this->got_plt_->offset();
+ const off_t got_size = this->got_plt_->data_size();
+ unsigned char* const got_view = of->get_output_view(got_file_offset,
+ got_size);
+
+ unsigned char* pov = oview;
+
+ elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
+ elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
+
+ memcpy(pov, first_plt_entry, plt_entry_size);
+ if (!parameters->output_is_shared())
+ {
+ // We do a jmp relative to the PC at the end of this instruction.
+ elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 8
+ - (plt_address + 6));
+ elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 16
+ - (plt_address + 12));
+ }
+ pov += plt_entry_size;
+
+ unsigned char* got_pov = got_view;
+
+ memset(got_pov, 0, 24);
+ got_pov += 24;
+
+ unsigned int plt_offset = plt_entry_size;
+ unsigned int got_offset = 24;
+ const unsigned int count = this->count_;
+ for (unsigned int plt_index = 0;
+ plt_index < count;
+ ++plt_index,
+ pov += plt_entry_size,
+ got_pov += 8,
+ plt_offset += plt_entry_size,
+ got_offset += 8)
+ {
+ // Set and adjust the PLT entry itself.
+ memcpy(pov, plt_entry, plt_entry_size);
+ if (parameters->output_is_shared())
+ // FIXME(csilvers): what's the right thing to write here?
+ elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
+ else
+ elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
+ (got_address + got_offset
+ - (plt_address + plt_offset
+ + 6)));
+
+ elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index);
+ elfcpp::Swap<32, false>::writeval(pov + 12,
+ - (plt_offset + plt_entry_size));
+
+ // Set the entry in the GOT.
+ elfcpp::Swap<64, false>::writeval(got_pov, plt_address + plt_offset + 6);
+ }
+
+ gold_assert(pov - oview == oview_size);
+ gold_assert(got_pov - got_view == got_size);
+
+ of->write_output_view(offset, oview_size, oview);
+ of->write_output_view(got_file_offset, got_size, got_view);
+}
+
+// Create a PLT entry for a global symbol.
+
+void
+Target_x86_64::make_plt_entry(Symbol_table* symtab, Layout* layout,
+ Symbol* gsym)
+{
+ if (gsym->has_plt_offset())
+ return;
+
+ if (this->plt_ == NULL)
+ {
+ // Create the GOT sections first.
+ this->got_section(symtab, layout);
+
+ this->plt_ = new Output_data_plt_x86_64(layout, this->got_plt_);
+ layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
+ (elfcpp::SHF_ALLOC
+ | elfcpp::SHF_EXECINSTR),
+ this->plt_);
+ }
+
+ this->plt_->add_entry(gsym);
+}
+
+// Handle a relocation against a non-function symbol defined in a
+// dynamic object. The traditional way to handle this is to generate
+// a COPY relocation to copy the variable at runtime from the shared
+// object into the executable's data segment. However, this is
+// undesirable in general, as if the size of the object changes in the
+// dynamic object, the executable will no longer work correctly. If
+// this relocation is in a writable section, then we can create a
+// dynamic reloc and the dynamic linker will resolve it to the correct
+// address at runtime. However, we do not want do that if the
+// relocation is in a read-only section, as it would prevent the
+// readonly segment from being shared. And if we have to eventually
+// generate a COPY reloc, then any dynamic relocations will be
+// useless. So this means that if this is a writable section, we need
+// to save the relocation until we see whether we have to create a
+// COPY relocation for this symbol for any other relocation.
+
+void
+Target_x86_64::copy_reloc(const General_options* options,
+ Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<64, false>* object,
+ unsigned int data_shndx, Symbol* gsym,
+ const elfcpp::Rela<64, false>& rel)
+{
+ Sized_symbol<64>* ssym;
+ ssym = symtab->get_sized_symbol SELECT_SIZE_NAME(64) (gsym
+ SELECT_SIZE(64));
+
+ if (!Copy_relocs<64, false>::need_copy_reloc(options, object,
+ data_shndx, ssym))
+ {
+ // So far we do not need a COPY reloc. Save this relocation.
+ // If it turns out that we never need a COPY reloc for this
+ // symbol, then we will emit the relocation.
+ if (this->copy_relocs_ == NULL)
+ this->copy_relocs_ = new Copy_relocs<64, false>();
+ this->copy_relocs_->save(ssym, object, data_shndx, rel);
+ }
+ else
+ {
+ // Allocate space for this symbol in the .bss section.
+
+ elfcpp::Elf_types<64>::Elf_WXword symsize = ssym->symsize();
+
+ // There is no defined way to determine the required alignment
+ // of the symbol. We pick the alignment based on the size. We
+ // set an arbitrary maximum of 256.
+ unsigned int align;
+ for (align = 1; align < 512; align <<= 1)
+ if ((symsize & align) != 0)
+ break;
+
+ if (this->dynbss_ == NULL)
+ {
+ this->dynbss_ = new Output_data_space(align);
+ layout->add_output_section_data(".bss",
+ elfcpp::SHT_NOBITS,
+ (elfcpp::SHF_ALLOC
+ | elfcpp::SHF_WRITE),
+ this->dynbss_);
+ }
+
+ Output_data_space* dynbss = this->dynbss_;
+
+ if (align > dynbss->addralign())
+ dynbss->set_space_alignment(align);
+
+ off_t dynbss_size = dynbss->data_size();
+ dynbss_size = align_address(dynbss_size, align);
+ off_t offset = dynbss_size;
+ dynbss->set_space_size(dynbss_size + symsize);
+
+ // Define the symbol in the .dynbss section.
+ symtab->define_in_output_data(this, ssym->name(), ssym->version(),
+ dynbss, offset, symsize, ssym->type(),
+ ssym->binding(), ssym->visibility(),
+ ssym->nonvis(), false, false);
+
+ // Add the COPY reloc.
+ ssym->set_needs_dynsym_entry();
+ Reloc_section* rel_dyn = this->rel_dyn_section(layout);
+ rel_dyn->add_global(ssym, elfcpp::R_X86_64_COPY, dynbss, offset,
+ rel.get_r_addend());
+ }
+}
+
+
+// Optimize the TLS relocation type based on what we know about the
+// symbol. IS_FINAL is true if the final address of this symbol is
+// known at link time.
+
+unsigned int
+Target_x86_64::optimize_tls_reloc(bool is_final, int r_type)
+{
+ return is_final ? r_type : 0;
+#if 0
+ // If we are generating a shared library, then we can't do anything
+ // in the linker.
+ if (parameters->output_is_shared())
+ return r_type;
+
+ switch (r_type)
+ {
+ case elfcpp::R_X86_64_TLSGD:
+ // These are Global-Dynamic which permits fully general TLS
+ // access. Since we know that we are generating an executable,
+ // we can convert this to Initial-Exec. If we also know that
+ // this is a local symbol, we can further switch to Local-Exec.
+ if (is_final)
+ return elfcpp::R_X86_64_TLS_LE_64;
+ return elfcpp::R_X86_64_TLS_IE_64;
+
+ case elfcpp::R_X86_64_TLS_LDM:
+ // This is Local-Dynamic, which refers to a local symbol in the
+ // dynamic TLS block. Since we know that we generating an
+ // executable, we can switch to Local-Exec.
+ return elfcpp::R_X86_64_TLS_LE_64;
+
+ case elfcpp::R_X86_64_TLS_LDO_64:
+ // Another type of Local-Dynamic relocation.
+ return elfcpp::R_X86_64_TLS_LE;
+
+ case elfcpp::R_X86_64_TLS_IE:
+ case elfcpp::R_X86_64_TLS_GOTIE:
+ case elfcpp::R_X86_64_TLS_IE_64:
+ // These are Initial-Exec relocs which get the thread offset
+ // from the GOT. If we know that we are linking against the
+ // local symbol, we can switch to Local-Exec, which links the
+ // thread offset into the instruction.
+ if (is_final)
+ return elfcpp::R_X86_64_TLS_LE_64;
+ return r_type;
+
+ case elfcpp::R_X86_64_TLS_LE:
+ case elfcpp::R_X86_64_TLS_LE_64:
+ // When we already have Local-Exec, there is nothing further we
+ // can do.
+ return r_type;
+
+ default:
+ gold_unreachable();
+ }
+#endif
+}
+
+// Scan a relocation for a local symbol.
+
+inline void
+Target_x86_64::Scan::local(const General_options&,
+ Symbol_table* symtab,
+ Layout* layout,
+ Target_x86_64* target,
+ Sized_relobj<64, false>* object,
+ unsigned int,
+ const elfcpp::Rela<64, false>&,
+ unsigned int r_type,
+ const elfcpp::Sym<64, false>&)
+{
+ switch (r_type)
+ {
+ case elfcpp::R_X86_64_NONE:
+ break;
+
+ case elfcpp::R_X86_64_64:
+ case elfcpp::R_X86_64_32:
+ case elfcpp::R_X86_64_32S:
+ case elfcpp::R_X86_64_16:
+ case elfcpp::R_X86_64_8:
+ // FIXME: If we are generating a shared object we need to copy
+ // this relocation into the object.
+ gold_assert(!parameters->output_is_shared());
+ break;
+
+ case elfcpp::R_X86_64_PC64:
+ case elfcpp::R_X86_64_PC32:
+ case elfcpp::R_X86_64_PC16:
+ case elfcpp::R_X86_64_PC8:
+ break;
+
+ case elfcpp::R_X86_64_GOTOFF64:
+ case elfcpp::R_X86_64_GOTPCREL:
+ // We need a GOT section.
+ target->got_section(symtab, layout);
+ break;
+
+ case elfcpp::R_X86_64_COPY:
+ case elfcpp::R_X86_64_GLOB_DAT:
+ case elfcpp::R_X86_64_JUMP_SLOT:
+ case elfcpp::R_X86_64_RELATIVE:
+ case elfcpp::R_X86_64_TPOFF64:
+ case elfcpp::R_X86_64_TPOFF32:
+ case elfcpp::R_X86_64_DTPMOD64:
+ case elfcpp::R_X86_64_DTPOFF64:
+ case elfcpp::R_X86_64_DTPOFF32:
+ case elfcpp::R_X86_64_TLSDESC:
+ fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"),
+ program_name, object->name().c_str(), r_type);
+ gold_exit(false);
+ break;
+
+#if 0
+ case elfcpp::R_X86_64_TLS_IE:
+ case elfcpp::R_X86_64_TLS_GOTIE:
+ case elfcpp::R_X86_64_TLS_LE:
+ case elfcpp::R_X86_64_TLS_GD:
+ case elfcpp::R_X86_64_TLS_LDM:
+ case elfcpp::R_X86_64_TLS_LDO_64:
+ case elfcpp::R_X86_64_TLS_IE_64:
+ case elfcpp::R_X86_64_TLS_LE_64:
+ {
+ bool output_is_shared = parameters->output_is_shared();
+ r_type = Target_x86_64::optimize_tls_reloc(!output_is_shared,
+ r_type);
+ switch (r_type)
+ {
+ case elfcpp::R_X86_64_TLS_LE:
+ case elfcpp::R_X86_64_TLS_LE_64:
+ // FIXME: If generating a shared object, we need to copy
+ // this relocation into the object.
+ gold_assert(!output_is_shared);
+ break;
+
+ case elfcpp::R_X86_64_TLS_IE:
+ case elfcpp::R_X86_64_TLS_GOTIE:
+ case elfcpp::R_X86_64_TLS_GD:
+ case elfcpp::R_X86_64_TLS_LDM:
+ case elfcpp::R_X86_64_TLS_LDO_64:
+ case elfcpp::R_X86_64_TLS_IE_64:
+ fprintf(stderr,
+ _("%s: %s: unsupported reloc %u against local symbol\n"),
+ program_name, object->name().c_str(), r_type);
+ break;
+ }
+ }
+ break;
+#endif
+
+#if 0
+ case elfcpp::R_X86_64_GOT32:
+ case elfcpp::R_X86_64_PLT32:
+ case elfcpp::R_X86_64_TLS_GD_64:
+ case elfcpp::R_X86_64_TLS_GD_PUSH:
+ case elfcpp::R_X86_64_TLS_GD_CALL:
+ case elfcpp::R_X86_64_TLS_GD_POP:
+ case elfcpp::R_X86_64_TLS_LDM_64:
+ case elfcpp::R_X86_64_TLS_LDM_PUSH:
+ case elfcpp::R_X86_64_TLS_LDM_CALL:
+ case elfcpp::R_X86_64_TLS_LDM_POP:
+#endif
+ default:
+ fprintf(stderr, _("%s: %s: unsupported reloc %u against local symbol\n"),
+ program_name, object->name().c_str(), r_type);
+ break;
+ }
+}
+
+
+// Scan a relocation for a global symbol.
+
+inline void
+Target_x86_64::Scan::global(const General_options& options,
+ Symbol_table* symtab,
+ Layout* layout,
+ Target_x86_64* target,
+ Sized_relobj<64, false>* object,
+ unsigned int data_shndx,
+ const elfcpp::Rela<64, false>& reloc,
+ unsigned int r_type,
+ Symbol* gsym)
+{
+ switch (r_type)
+ {
+ case elfcpp::R_X86_64_NONE:
+ break;
+
+ case elfcpp::R_X86_64_64:
+ case elfcpp::R_X86_64_PC64:
+ case elfcpp::R_X86_64_32:
+ case elfcpp::R_X86_64_32S:
+ case elfcpp::R_X86_64_PC32:
+ case elfcpp::R_X86_64_16:
+ case elfcpp::R_X86_64_PC16:
+ case elfcpp::R_X86_64_8:
+ case elfcpp::R_X86_64_PC8:
+ // FIXME: If we are generating a shared object we may need to
+ // copy this relocation into the object. If this symbol is
+ // defined in a shared object, we may need to copy this
+ // relocation in order to avoid a COPY relocation.
+ gold_assert(!parameters->output_is_shared());
+
+ if (gsym->is_from_dynobj())
+ {
+ // This symbol is defined in a dynamic object. If it is a
+ // function, we make a PLT entry. Otherwise we need to
+ // either generate a COPY reloc or copy this reloc.
+ if (gsym->type() == elfcpp::STT_FUNC)
+ target->make_plt_entry(symtab, layout, gsym);
+ else
+ target->copy_reloc(&options, symtab, layout, object, data_shndx,
+ gsym, reloc);
+ }
+
+ break;
+
+ case elfcpp::R_X86_64_GOT32:
+ {
+ // The symbol requires a GOT entry.
+ Output_data_got<64, false>* got = target->got_section(symtab, layout);
+ if (got->add_global(gsym))
+ {
+ // If this symbol is not fully resolved, we need to add a
+ // dynamic relocation for it.
+ if (!gsym->final_value_is_known())
+ {
+ Reloc_section* rel_dyn = target->rel_dyn_section(layout);
+ rel_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT, got,
+ gsym->got_offset(), reloc.get_r_addend());
+ }
+ }
+ }
+ break;
+
+ case elfcpp::R_X86_64_PLT32:
+ // If the symbol is fully resolved, this is just a PC32 reloc.
+ // Otherwise we need a PLT entry.
+ if (gsym->final_value_is_known())
+ break;
+ target->make_plt_entry(symtab, layout, gsym);
+ break;
+
+ case elfcpp::R_X86_64_GOTOFF64:
+ case elfcpp::R_X86_64_GOTPC32:
+ case elfcpp::R_X86_64_GOTPCREL:
+ // We need a GOT section.
+ target->got_section(symtab, layout);
+ break;
+
+#if 0
+ case elfcpp::R_X86_64_COPY:
+ case elfcpp::R_X86_64_GLOB_DAT:
+ case elfcpp::R_X86_64_JUMP_SLOT:
+ case elfcpp::R_X86_64_RELATIVE:
+ case elfcpp::R_X86_64_TLS_TPOFF:
+ case elfcpp::R_X86_64_DTPMOD64:
+ case elfcpp::R_X86_64_DTPOFF64:
+ case elfcpp::R_X86_64_DTPOFF32:
+ case elfcpp::R_X86_64_TLS_TPOFF64:
+ case elfcpp::R_X86_64_TLS_DESC:
+ fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"),
+ program_name, object->name().c_str(), r_type);
+ gold_exit(false);
+ break;
+#endif
+
+#if 0
+ case elfcpp::R_X86_64_TLS_IE:
+ case elfcpp::R_X86_64_TLS_GOTIE:
+ case elfcpp::R_X86_64_TLS_LE:
+ case elfcpp::R_X86_64_TLS_GD:
+ case elfcpp::R_X86_64_TLS_LDM:
+ case elfcpp::R_X86_64_TLS_LDO_64:
+ case elfcpp::R_X86_64_TLS_IE_64:
+ case elfcpp::R_X86_64_TLS_LE_64:
+ {
+ const bool is_final = gsym->final_value_is_known();
+ r_type = Target_x86_64::optimize_tls_reloc(is_final, r_type);
+ switch (r_type)
+ {
+ case elfcpp::R_X86_64_TLS_LE:
+ case elfcpp::R_X86_64_TLS_LE_64:
+ // FIXME: If generating a shared object, we need to copy
+ // this relocation into the object.
+ gold_assert(!parameters->output_is_shared());
+ break;
+
+ case elfcpp::R_X86_64_TLS_IE:
+ case elfcpp::R_X86_64_TLS_GOTIE:
+ case elfcpp::R_X86_64_TLS_GD:
+ case elfcpp::R_X86_64_TLS_LDM:
+ case elfcpp::R_X86_64_TLS_LDO_64:
+ case elfcpp::R_X86_64_TLS_IE_64:
+ fprintf(stderr,
+ _("%s: %s: unsupported reloc %u "
+ "against global symbol %s\n"),
+ program_name, object->name().c_str(), r_type,
+ gsym->name());
+ break;
+ }
+ }
+ break;
+#endif
+
+#if 0
+ case elfcpp::R_X86_64_TLS_GD_64:
+ case elfcpp::R_X86_64_TLS_GD_PUSH:
+ case elfcpp::R_X86_64_TLS_GD_CALL:
+ case elfcpp::R_X86_64_TLS_GD_POP:
+ case elfcpp::R_X86_64_TLS_LDM_64:
+ case elfcpp::R_X86_64_TLS_LDM_PUSH:
+ case elfcpp::R_X86_64_TLS_LDM_CALL:
+ case elfcpp::R_X86_64_TLS_LDM_POP:
+#endif
+ default:
+ fprintf(stderr,
+ _("%s: %s: unsupported reloc %u against global symbol %s\n"),
+ program_name, object->name().c_str(), r_type, gsym->name());
+ break;
+ }
+}
+
+// Scan relocations for a section.
+
+void
+Target_x86_64::scan_relocs(const General_options& options,
+ Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj<64, false>* object,
+ unsigned int data_shndx,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ size_t local_symbol_count,
+ const unsigned char* plocal_symbols,
+ Symbol** global_symbols)
+{
+ if (sh_type == elfcpp::SHT_REL)
+ {
+ fprintf(stderr, _("%s: %s: unsupported REL reloc section\n"),
+ program_name, object->name().c_str());
+ gold_exit(false);
+ }
+
+ gold::scan_relocs<64, false, Target_x86_64, elfcpp::SHT_RELA,
+ Target_x86_64::Scan>(
+ options,
+ symtab,
+ layout,
+ this,
+ object,
+ data_shndx,
+ prelocs,
+ reloc_count,
+ local_symbol_count,
+ plocal_symbols,
+ global_symbols);
+}
+
+// Finalize the sections.
+
+void
+Target_x86_64::do_finalize_sections(Layout* layout)
+{
+ // Fill in some more dynamic tags.
+ Output_data_dynamic* const odyn = layout->dynamic_data();
+ if (odyn != NULL)
+ {
+ if (this->got_plt_ != NULL)
+ odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
+
+ if (this->plt_ != NULL)
+ {
+ const Output_data* od = this->plt_->rel_plt();
+ odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
+ odyn->add_section_address(elfcpp::DT_JMPREL, od);
+ odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_RELA);
+ }
+
+ if (this->rel_dyn_ != NULL)
+ {
+ const Output_data* od = this->rel_dyn_;
+ odyn->add_section_address(elfcpp::DT_RELA, od);
+ odyn->add_section_size(elfcpp::DT_RELSZ, od);
+ odyn->add_constant(elfcpp::DT_RELAENT,
+ elfcpp::Elf_sizes<64>::rel_size);
+ }
+
+ if (!parameters->output_is_shared())
+ {
+ // The value of the DT_DEBUG tag is filled in by the dynamic
+ // linker at run time, and used by the debugger.
+ odyn->add_constant(elfcpp::DT_DEBUG, 0);
+ }
+ }
+
+ // Emit any relocs we saved in an attempt to avoid generating COPY
+ // relocs.
+ if (this->copy_relocs_ == NULL)
+ return;
+ if (this->copy_relocs_->any_to_emit())
+ {
+ Reloc_section* rel_dyn = this->rel_dyn_section(layout);
+ this->copy_relocs_->emit(rel_dyn);
+ }
+ delete this->copy_relocs_;
+ this->copy_relocs_ = NULL;
+}
+
+// Perform a relocation.
+
+inline bool
+Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo,
+ Target_x86_64* target,
+ size_t relnum,
+ const elfcpp::Rela<64, false>& rel,
+ unsigned int r_type,
+ const Sized_symbol<64>* gsym,
+ const Symbol_value<64>* psymval,
+ unsigned char* view,
+ elfcpp::Elf_types<64>::Elf_Addr address,
+ off_t view_size)
+{
+ if (this->skip_call_tls_get_addr_)
+ {
+ if (r_type != elfcpp::R_X86_64_PLT32
+ || gsym == NULL
+ || strcmp(gsym->name(), "___tls_get_addr") != 0)
+ {
+ fprintf(stderr, _("%s: %s: missing expected TLS relocation\n"),
+ program_name,
+ relinfo->location(relnum, rel.get_r_offset()).c_str());
+ gold_exit(false);
+ }
+
+ this->skip_call_tls_get_addr_ = false;
+
+ return false;
+ }
+
+ // Pick the value to use for symbols defined in shared objects.
+ Symbol_value<64> symval;
+ if (gsym != NULL && gsym->is_from_dynobj() && gsym->has_plt_offset())
+ {
+ symval.set_output_value(target->plt_section()->address()
+ + gsym->plt_offset());
+ psymval = &symval;
+ }
+
+ const Sized_relobj<64, false>* object = relinfo->object;
+ const elfcpp::Elf_Xword addend = rel.get_r_addend();
+
+ switch (r_type)
+ {
+ case elfcpp::R_X86_64_NONE:
+ break;
+
+ case elfcpp::R_X86_64_64:
+ Relocate_functions<64, false>::rela64(view, object, psymval, addend);
+ break;
+
+ case elfcpp::R_X86_64_PC64:
+ Relocate_functions<64, false>::pcrela64(view, object, psymval, addend,
+ address);
+ break;
+
+ case elfcpp::R_X86_64_32:
+ // FIXME: Needs error checking.
+ Relocate_functions<64, false>::rela32(view, object, psymval, addend);
+ break;
+
+ case elfcpp::R_X86_64_32S:
+ // FIXME: Needs error checking.
+ Relocate_functions<64, false>::rela32(view, object, psymval, addend);
+ break;
+
+ case elfcpp::R_X86_64_PC32:
+ Relocate_functions<64, false>::pcrela32(view, object, psymval, addend,
+ address);
+ break;
+
+ case elfcpp::R_X86_64_16:
+ Relocate_functions<64, false>::rela16(view, object, psymval, addend);
+ break;
+
+ case elfcpp::R_X86_64_PC16:
+ Relocate_functions<64, false>::pcrela16(view, object, psymval, addend,
+ address);
+ break;
+
+ case elfcpp::R_X86_64_8:
+ Relocate_functions<64, false>::rela8(view, object, psymval, addend);
+ break;
+
+ case elfcpp::R_X86_64_PC8:
+ Relocate_functions<64, false>::pcrela8(view, object, psymval, addend,
+ address);
+ break;
+
+ case elfcpp::R_X86_64_PLT32:
+ gold_assert(gsym->has_plt_offset()
+ || gsym->final_value_is_known());
+ Relocate_functions<64, false>::pcrela32(view, object, psymval, addend,
+ address);
+ break;
+
+ case elfcpp::R_X86_64_GOT32:
+ // Local GOT offsets not yet supported.
+ gold_assert(gsym);
+ gold_assert(gsym->has_got_offset());
+ Relocate_functions<64, false>::rela32(view, gsym->got_offset(), addend);
+ break;
+
+ case elfcpp::R_X86_64_GOTOFF64:
+ {
+ elfcpp::Elf_types<64>::Elf_Addr value;
+ value = (psymval->value(object, 0)
+ - target->got_section(NULL, NULL)->address());
+ Relocate_functions<64, false>::rela64(view, value, addend);
+ }
+ break;
+
+ case elfcpp::R_X86_64_GOTPCREL:
+ {
+ gold_assert(gsym);
+ elfcpp::Elf_types<64>::Elf_Addr value;
+ // FIXME(csilvers): this is probably totally wrong for G + GOT
+ value = (target->got_section(NULL, NULL)->address()
+ + (gsym->has_got_offset() ? gsym->got_offset() : 0));
+ Relocate_functions<64, false>::pcrela32(view, value, addend, address);
+ }
+ break;
+
+ case elfcpp::R_X86_64_COPY:
+ case elfcpp::R_X86_64_GLOB_DAT:
+ case elfcpp::R_X86_64_JUMP_SLOT:
+ case elfcpp::R_X86_64_RELATIVE:
+ case elfcpp::R_X86_64_TPOFF64:
+ case elfcpp::R_X86_64_TPOFF32:
+ case elfcpp::R_X86_64_DTPMOD64:
+ case elfcpp::R_X86_64_DTPOFF64:
+ case elfcpp::R_X86_64_DTPOFF32:
+ case elfcpp::R_X86_64_TLSDESC:
+ fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"),
+ program_name,
+ relinfo->location(relnum, rel.get_r_offset()).c_str(),
+ r_type);
+ gold_exit(false);
+ break;
+
+#if 0
+ case elfcpp::R_X86_64_TLS_IE:
+ case elfcpp::R_X86_64_TLS_GOTIE:
+ case elfcpp::R_X86_64_TLS_LE:
+ case elfcpp::R_X86_64_TLS_GD:
+ case elfcpp::R_X86_64_TLS_LDM:
+ case elfcpp::R_X86_64_TLS_LDO_64:
+ case elfcpp::R_X86_64_TLS_IE_64:
+ case elfcpp::R_X86_64_TLS_LE_64:
+ this->relocate_tls(relinfo, relnum, rel, r_type, gsym, psymval, view,
+ address, view_size);
+ break;
+#else
+ view_size++; // this is to make view_size used
+#endif
+
+#if 0
+ case elfcpp::R_X86_64_TLS_GD_64:
+ case elfcpp::R_X86_64_TLS_GD_PUSH:
+ case elfcpp::R_X86_64_TLS_GD_CALL:
+ case elfcpp::R_X86_64_TLS_GD_POP:
+ case elfcpp::R_X86_64_TLS_LDM_64:
+ case elfcpp::R_X86_64_TLS_LDM_PUSH:
+ case elfcpp::R_X86_64_TLS_LDM_CALL:
+ case elfcpp::R_X86_64_TLS_LDM_POP:
+#endif
+ default:
+ fprintf(stderr, _("%s: %s: unsupported reloc %u\n"),
+ program_name,
+ relinfo->location(relnum, rel.get_r_offset()).c_str(),
+ r_type);
+ // gold_exit(false);
+ break;
+ }
+
+ return true;
+}
+
+// Perform a TLS relocation.
+
+inline void
+Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>*, // relinfo,
+ size_t , // relnum,
+ const elfcpp::Rela<64, false>& , // rel,
+ unsigned int , // r_type,
+ const Sized_symbol<64>* , // gsym,
+ const Symbol_value<64>* , // psymval,
+ unsigned char* , // view,
+ elfcpp::Elf_types<64>::Elf_Addr,
+ off_t)// view_size)
+{
+#if 0
+ Output_segment* tls_segment = relinfo->layout->tls_segment();
+ if (tls_segment == NULL)
+ {
+ fprintf(stderr, _("%s: %s: TLS reloc but no TLS segment\n"),
+ program_name,
+ relinfo->location(relnum, rel.get_r_offset()).c_str());
+ gold_exit(false);
+ }
+
+ elfcpp::Elf_types<64>::Elf_Addr value = psymval->value(relinfo->object, 0);
+
+ const bool is_final = (gsym == NULL
+ ? !parameters->output_is_shared()
+ : gsym->final_value_is_known());
+ const unsigned int opt_r_type =
+ Target_x86_64::optimize_tls_reloc(is_final, r_type);
+ switch (r_type)
+ {
+ case elfcpp::R_X86_64_TLS_LE_64:
+ value = tls_segment->vaddr() + tls_segment->memsz() - value;
+ Relocate_functions<64, false>::rel64(view, value);
+ break;
+
+ case elfcpp::R_X86_64_TLS_LE:
+ value = value - (tls_segment->vaddr() + tls_segment->memsz());
+ Relocate_functions<64, false>::rel64(view, value);
+ break;
+
+ case elfcpp::R_X86_64_TLS_IE:
+ case elfcpp::R_X86_64_TLS_GOTIE:
+ case elfcpp::R_X86_64_TLS_IE_64:
+ if (opt_r_type == elfcpp::R_X86_64_TLS_LE_64)
+ {
+ Target_x86_64::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
+ rel, r_type, value, view,
+ view_size);
+ break;
+ }
+ fprintf(stderr, _("%s: %s: unsupported reloc type %u\n"),
+ program_name,
+ relinfo->location(relnum, rel.get_r_offset()).c_str(),
+ r_type);
+ // gold_exit(false);
+ break;
+
+ case elfcpp::R_X86_64_TLS_GD:
+ if (opt_r_type == elfcpp::R_X86_64_TLS_LE_64)
+ {
+ this->tls_gd_to_le(relinfo, relnum, tls_segment,
+ rel, r_type, value, view,
+ view_size);
+ break;
+ }
+ fprintf(stderr, _("%s: %s: unsupported reloc %u\n"),
+ program_name,
+ relinfo->location(relnum, rel.get_r_offset()).c_str(),
+ r_type);
+ // gold_exit(false);
+ break;
+
+ case elfcpp::R_X86_64_TLS_LDM:
+ case elfcpp::R_X86_64_TLS_LDO_64:
+ fprintf(stderr, _("%s: %s: unsupported reloc %u\n"),
+ program_name,
+ relinfo->location(relnum, rel.get_r_offset()).c_str(),
+ r_type);
+ // gold_exit(false);
+ break;
+ }
+#endif
+}
+
+// Do a relocation in which we convert a TLS Initial-Exec to a
+// Local-Exec.
+
+inline void
+Target_x86_64::Relocate::tls_ie_to_le(const Relocate_info<64, false>* , // relinfo,
+ size_t , // relnum,
+ Output_segment* , // tls_segment,
+ const elfcpp::Rela<64, false>& , // rel,
+ unsigned int , // r_type,
+ elfcpp::Elf_types<64>::Elf_Addr , // value,
+ unsigned char* , // view,
+ off_t) // view_size)
+{
+#if 0
+ // We have to actually change the instructions, which means that we
+ // need to examine the opcodes to figure out which instruction we
+ // are looking at.
+ if (r_type == elfcpp::R_X86_64_TLS_IE)
+ {
+ // movl %gs:XX,%eax ==> movl $YY,%eax
+ // movl %gs:XX,%reg ==> movl $YY,%reg
+ // addl %gs:XX,%reg ==> addl $YY,%reg
+ Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -1);
+ Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 4);
+
+ unsigned char op1 = view[-1];
+ if (op1 == 0xa1)
+ {
+ // movl XX,%eax ==> movl $YY,%eax
+ view[-1] = 0xb8;
+ }
+ else
+ {
+ Target_x86_64::Relocate::check_range(relinfo, relnum, rel,
+ view_size, -2);
+
+ unsigned char op2 = view[-2];
+ if (op2 == 0x8b)
+ {
+ // movl XX,%reg ==> movl $YY,%reg
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel,
+ (op1 & 0xc7) == 0x05);
+ view[-2] = 0xc7;
+ view[-1] = 0xc0 | ((op1 >> 3) & 7);
+ }
+ else if (op2 == 0x03)
+ {
+ // addl XX,%reg ==> addl $YY,%reg
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel,
+ (op1 & 0xc7) == 0x05);
+ view[-2] = 0x81;
+ view[-1] = 0xc0 | ((op1 >> 3) & 7);
+ }
+ else
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, 0);
+ }
+ }
+ else
+ {
+ // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
+ // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
+ // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
+ Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -2);
+ Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 4);
+
+ unsigned char op1 = view[-1];
+ unsigned char op2 = view[-2];
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel,
+ (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
+ if (op2 == 0x8b)
+ {
+ // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
+ view[-2] = 0xc7;
+ view[-1] = 0xc0 | ((op1 >> 3) & 7);
+ }
+ else if (op2 == 0x2b)
+ {
+ // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
+ view[-2] = 0x81;
+ view[-1] = 0xe8 | ((op1 >> 3) & 7);
+ }
+ else if (op2 == 0x03)
+ {
+ // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
+ view[-2] = 0x81;
+ view[-1] = 0xc0 | ((op1 >> 3) & 7);
+ }
+ else
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel, 0);
+ }
+
+ value = tls_segment->vaddr() + tls_segment->memsz() - value;
+ if (r_type == elfcpp::R_X86_64_TLS_IE || r_type == elfcpp::R_X86_64_TLS_GOTIE)
+ value = - value;
+
+ Relocate_functions<64, false>::rel64(view, value);
+#endif
+}
+
+// Do a relocation in which we convert a TLS Global-Dynamic to a
+// Local-Exec.
+
+inline void
+Target_x86_64::Relocate::tls_gd_to_le(const Relocate_info<64, false>* , // relinfo,
+ size_t , // relnum,
+ Output_segment* , // tls_segment,
+ const elfcpp::Rela<64, false>& , // rel,
+ unsigned int,
+ elfcpp::Elf_types<64>::Elf_Addr , // value,
+ unsigned char* , // view,
+ off_t)// view_size)
+{
+#if 0
+ // leal foo(,%reg,1),%eax; call ___tls_get_addr
+ // ==> movl %gs,0,%eax; subl $foo@tpoff,%eax
+ // leal foo(%reg),%eax; call ___tls_get_addr
+ // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
+
+ Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -2);
+ Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, 9);
+
+ unsigned char op1 = view[-1];
+ unsigned char op2 = view[-2];
+
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel,
+ op2 == 0x8d || op2 == 0x04);
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel,
+ view[4] == 0xe8);
+
+ int roff = 5;
+
+ if (op2 == 0x04)
+ {
+ Target_x86_64::Relocate::check_range(relinfo, relnum, rel, view_size, -3);
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel,
+ view[-3] == 0x8d);
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel,
+ ((op1 & 0xc7) == 0x05
+ && op1 != (4 << 3)));
+ memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
+ }
+ else
+ {
+ Target_x86_64::Relocate::check_tls(relinfo, relnum, rel,
+ (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
+ if (rel.get_r_offset() + 9 < view_size && view[9] == 0x90)
+ {
+ // There is a trailing nop. Use the size byte subl.
+ memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
+ roff = 6;
+ }
+ else
+ {
+ // Use the five byte subl.
+ memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
+ }
+ }
+
+ value = tls_segment->vaddr() + tls_segment->memsz() - value;
+ Relocate_functions<64, false>::rel64(view + roff, value);
+
+ // The next reloc should be a PLT32 reloc against __tls_get_addr.
+ // We can skip it.
+ this->skip_call_tls_get_addr_ = true;
+#endif
+}
+
+// Check the range for a TLS relocation.
+
+inline void
+Target_x86_64::Relocate::check_range(const Relocate_info<64, false>* relinfo,
+ size_t relnum,
+ const elfcpp::Rela<64, false>& rel,
+ off_t view_size, off_t off)
+{
+ off_t offset = rel.get_r_offset() + off;
+ if (offset < 0 || offset > view_size)
+ {
+ fprintf(stderr, _("%s: %s: TLS relocation out of range\n"),
+ program_name,
+ relinfo->location(relnum, rel.get_r_offset()).c_str());
+ gold_exit(false);
+ }
+}
+
+// Check the validity of a TLS relocation. This is like assert.
+
+inline void
+Target_x86_64::Relocate::check_tls(const Relocate_info<64, false>* relinfo,
+ size_t relnum,
+ const elfcpp::Rela<64, false>& rel,
+ bool valid)
+{
+ if (!valid)
+ {
+ fprintf(stderr,
+ _("%s: %s: TLS relocation against invalid instruction\n"),
+ program_name,
+ relinfo->location(relnum, rel.get_r_offset()).c_str());
+ gold_exit(false);
+ }
+}
+
+// Relocate section data.
+
+void
+Target_x86_64::relocate_section(const Relocate_info<64, false>* relinfo,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ unsigned char* view,
+ elfcpp::Elf_types<64>::Elf_Addr address,
+ off_t view_size)
+{
+ gold_assert(sh_type == elfcpp::SHT_RELA);
+
+ gold::relocate_section<64, false, Target_x86_64, elfcpp::SHT_RELA,
+ Target_x86_64::Relocate>(
+ relinfo,
+ this,
+ prelocs,
+ reloc_count,
+ view,
+ address,
+ view_size);
+}
+
+// Return a string used to fill a code section with nops to take up
+// the specified length.
+
+std::string
+Target_x86_64::do_code_fill(off_t length)
+{
+ if (length >= 16)
+ {
+ // Build a jmpq instruction to skip over the bytes.
+ unsigned char jmp[5];
+ jmp[0] = 0xe9;
+ elfcpp::Swap_unaligned<64, false>::writeval(jmp + 1, length - 5);
+ return (std::string(reinterpret_cast<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 x86_64 object files.
+
+class Target_selector_x86_64 : public Target_selector
+{
+public:
+ Target_selector_x86_64()
+ : Target_selector(elfcpp::EM_X86_64, 64, false)
+ { }
+
+ Target*
+ recognize(int machine, int osabi, int abiversion);
+
+ private:
+ Target_x86_64* target_;
+};
+
+// Recognize an x86_64 object file when we already know that the machine
+// number is EM_X86_64.
+
+Target*
+Target_selector_x86_64::recognize(int, int, int)
+{
+ if (this->target_ == NULL)
+ this->target_ = new Target_x86_64();
+ return this->target_;
+}
+
+Target_selector_x86_64 target_selector_x86_64;
+
+} // End anonymous namespace.
projects / platform / upstream / binutils.git / commitdiff