From Craig Silverstein: x86_64 support.

5 files changed, 1670 insertions, 47 deletions

diff --git a/gold/Makefile.am b/gold/Makefile.am
index e476475..bb5d3f6 100644
--- a/gold/Makefile.am
+++ b/gold/Makefile.am
@@ -79,10 +79,10 @@ YFILES = \
 EXTRA_DIST = yyscript.c yyscript.h
 
 TARGETSOURCES = \
-	i386.cc
+	i386.cc x86_64.cc
 
 ALL_TARGETOBJS = \
-	i386.$(OBJEXT)
+	i386.$(OBJEXT) x86_64.$(OBJEXT)
 
 libgold_a_SOURCES = $(CCFILES) $(HFILES) $(YFILES)
 
diff --git a/gold/Makefile.in b/gold/Makefile.in
index 3ca6b8c..5db510e 100644
--- a/gold/Makefile.in
+++ b/gold/Makefile.in
@@ -325,10 +325,10 @@ YFILES = \
 
 EXTRA_DIST = yyscript.c yyscript.h
 TARGETSOURCES = \
-	i386.cc
+	i386.cc x86_64.cc
 
 ALL_TARGETOBJS = \
-	i386.$(OBJEXT)
+	i386.$(OBJEXT) x86_64.$(OBJEXT)
 
 libgold_a_SOURCES = $(CCFILES) $(HFILES) $(YFILES)
 sources_var = main.cc
@@ -465,6 +465,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/symtab.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/target-select.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/workqueue.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/x86_64.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/yyscript.Po@am__quote@
 
 .c.o:
diff --git a/gold/po/POTFILES.in b/gold/po/POTFILES.in
index c41e617..8c529d5 100644
--- a/gold/po/POTFILES.in
+++ b/gold/po/POTFILES.in
@@ -48,3 +48,4 @@ target-select.cc
 target-select.h
 workqueue.cc
 workqueue.h
+x86_64.cc
diff --git a/gold/po/gold.pot b/gold/po/gold.pot
index e2caf15..208c6b3 100644
--- a/gold/po/gold.pot
+++ b/gold/po/gold.pot
@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2007-09-25 22:42-0700\n"
+"POT-Creation-Date: 2007-10-01 14:30-0700\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -171,7 +171,7 @@ msgstr ""
 msgid "%s: %s: size of dynamic symbols is not multiple of symbol size\n"
 msgstr ""
 
-#: dynobj.cc:1266
+#: dynobj.cc:1302
 #, c-format
 msgid "%s: symbol %s has undefined version %s\n"
 msgstr ""
@@ -265,22 +265,23 @@ msgid "pthread_cond_signal failed"
 msgstr ""
 
 #. FIXME: This needs to specify the location somehow.
-#: i386.cc:130
+#: i386.cc:130 x86_64.cc:137
 #, c-format
 msgid "%s: missing expected TLS relocation\n"
 msgstr ""
 
-#: i386.cc:751 i386.cc:912 i386.cc:1174
+#: i386.cc:751 i386.cc:912 i386.cc:1174 x86_64.cc:733 x86_64.cc:886
+#: x86_64.cc:1169
 #, c-format
 msgid "%s: %s: unexpected reloc %u in object file\n"
 msgstr ""
 
-#: i386.cc:788 i386.cc:808
+#: i386.cc:788 i386.cc:808 x86_64.cc:767 x86_64.cc:788
 #, c-format
 msgid "%s: %s: unsupported reloc %u against local symbol\n"
 msgstr ""
 
-#: i386.cc:948 i386.cc:969
+#: i386.cc:948 i386.cc:969 x86_64.cc:920 x86_64.cc:942
 #, c-format
 msgid "%s: %s: unsupported reloc %u against global symbol %s\n"
 msgstr ""
@@ -290,32 +291,33 @@ msgstr ""
 msgid "%s: %s: unsupported RELA reloc section\n"
 msgstr ""
 
-#: i386.cc:1082
+#: i386.cc:1082 x86_64.cc:1055
 #, c-format
 msgid "%s: %s: missing expected TLS relocation\n"
 msgstr ""
 
-#: i386.cc:1206 i386.cc:1283 i386.cc:1294
+#: i386.cc:1206 i386.cc:1283 i386.cc:1294 x86_64.cc:1203 x86_64.cc:1281
+#: x86_64.cc:1290
 #, c-format
 msgid "%s: %s: unsupported reloc %u\n"
 msgstr ""
 
-#: i386.cc:1233
+#: i386.cc:1233 x86_64.cc:1231
 #, c-format
 msgid "%s: %s: TLS reloc but no TLS segment\n"
 msgstr ""
 
-#: i386.cc:1268
+#: i386.cc:1268 x86_64.cc:1266
 #, c-format
 msgid "%s: %s: unsupported reloc type %u\n"
 msgstr ""
 
-#: i386.cc:1477
+#: i386.cc:1477 x86_64.cc:1478
 #, c-format
 msgid "%s: %s: TLS relocation out of range\n"
 msgstr ""
 
-#: i386.cc:1495
+#: i386.cc:1495 x86_64.cc:1496
 #, c-format
 msgid "%s: %s: TLS relocation against invalid instruction\n"
 msgstr ""
@@ -386,62 +388,62 @@ msgstr ""
 msgid "%s: %s: local symbol %u section name out of range: %u >= %u\n"
 msgstr ""
 
-#: object.cc:857
+#: object.cc:860
 #, c-format
 msgid "%s: %s: unsupported ELF file type %d\n"
 msgstr ""
 
-#: object.cc:876 object.cc:929 object.cc:964
+#: object.cc:879 object.cc:932 object.cc:967
 #, c-format
 msgid "%s: %s: ELF file too short\n"
 msgstr ""
 
-#: object.cc:885
+#: object.cc:888
 #, c-format
 msgid "%s: %s: invalid ELF version 0\n"
 msgstr ""
 
-#: object.cc:888
+#: object.cc:891
 #, c-format
 msgid "%s: %s: unsupported ELF version %d\n"
 msgstr ""
 
-#: object.cc:896
+#: object.cc:899
 #, c-format
 msgid "%s: %s: invalid ELF class 0\n"
 msgstr ""
 
-#: object.cc:903
+#: object.cc:906
 #, c-format
 msgid "%s: %s: unsupported ELF class %d\n"
 msgstr ""
 
-#: object.cc:911
+#: object.cc:914
 #, c-format
 msgid "%s: %s: invalid ELF data encoding\n"
 msgstr ""
 
-#: object.cc:918
+#: object.cc:921
 #, c-format
 msgid "%s: %s: unsupported ELF data encoding %d\n"
 msgstr ""
 
-#: object.cc:941
+#: object.cc:944
 #, c-format
 msgid "%s: %s: not configured to support 32-bit big-endian object\n"
 msgstr ""
 
-#: object.cc:954
+#: object.cc:957
 #, c-format
 msgid "%s: %s: not configured to support 32-bit little-endian object\n"
 msgstr ""
 
-#: object.cc:976
+#: object.cc:979
 #, c-format
 msgid "%s: %s: not configured to support 64-bit big-endian object\n"
 msgstr ""
 
-#: object.cc:989
+#: object.cc:992
 #, c-format
 msgid "%s: %s: not configured to support 64-bit little-endian object\n"
 msgstr ""
@@ -597,37 +599,37 @@ msgstr ""
 msgid "%s: -%c: %s\n"
 msgstr ""
 
-#: output.cc:922
+#: output.cc:1011
 #, c-format
 msgid "%s: %s: invalid alignment %lu for section \"%s\"\n"
 msgstr ""
 
-#: output.cc:1571
+#: output.cc:1660
 #, c-format
 msgid "%s: %s: open: %s\n"
 msgstr ""
 
-#: output.cc:1580
+#: output.cc:1669
 #, c-format
 msgid "%s: %s: lseek: %s\n"
 msgstr ""
 
-#: output.cc:1587
+#: output.cc:1676
 #, c-format
 msgid "%s: %s: write: %s\n"
 msgstr ""
 
-#: output.cc:1597
+#: output.cc:1686
 #, c-format
 msgid "%s: %s: mmap: %s\n"
 msgstr ""
 
-#: output.cc:1611
+#: output.cc:1700
 #, c-format
 msgid "%s: %s: munmap: %s\n"
 msgstr ""
 
-#: output.cc:1619
+#: output.cc:1708
 #, c-format
 msgid "%s: %s: close: %s\n"
 msgstr ""
@@ -678,42 +680,37 @@ msgstr ""
 msgid "%s: %s: unsupported symbol binding %d for symbol %s\n"
 msgstr ""
 
-#: symtab.cc:476 symtab.cc:573
-#, c-format
-msgid "%s: %s: mixing 32-bit and 64-bit ELF objects\n"
-msgstr ""
-
-#: symtab.cc:493
+#: symtab.cc:518
 #, c-format
 msgid "%s: %s: bad global symbol name offset %u at %lu\n"
 msgstr ""
 
-#: symtab.cc:580
+#: symtab.cc:597
 #, c-format
 msgid "%s: %s: too few symbol versions\n"
 msgstr ""
 
-#: symtab.cc:600
+#: symtab.cc:617
 #, c-format
 msgid "%s: %s: bad symbol name offset %u at %lu\n"
 msgstr ""
 
-#: symtab.cc:653
+#: symtab.cc:670
 #, c-format
 msgid "%s: %s: versym for symbol %zu out of range: %u\n"
 msgstr ""
 
-#: symtab.cc:661
+#: symtab.cc:678
 #, c-format
 msgid "%s: %s: versym for symbol %zu has no name: %u\n"
 msgstr ""
 
-#: symtab.cc:1200 symtab.cc:1373
+#: symtab.cc:1248 symtab.cc:1445
 #, c-format
 msgid "%s: %s: unsupported symbol section 0x%x\n"
 msgstr ""
 
-#: symtab.cc:1570
+#: symtab.cc:1665
 #, c-format
 msgid "%s: %s: warning: %s\n"
 msgstr ""
@@ -727,3 +724,8 @@ msgstr ""
 #, c-format
 msgid "%s: %s: undefined reference to '%s'\n"
 msgstr ""
+
+#: x86_64.cc:965
+#, c-format
+msgid "%s: %s: unsupported REL reloc section\n"
+msgstr ""
diff --git a/gold/x86_64.cc b/gold/x86_64.cc
new file mode 100644
index 0000000..e2ad4bb
--- /dev/null
+++ b/gold/x86_64.cc
@@ -0,0 +1,1619 @@
+// x86_64.cc -- x86_64 target support for gold.
+
+// Copyright 2006, 2007, Free Software Foundation, Inc.
+// Written by Ian Lance Taylor <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.