]> git.ipfire.org Git - thirdparty/binutils-gdb.git/blobdiff - gold/output.cc
PR 11866
[thirdparty/binutils-gdb.git] / gold / output.cc
index 8aca916be0bea6a202effc92f0e8b591b787a8db..506edf7afe3156355a0b526fc34b44ba2af1cdb1 100644 (file)
@@ -1,6 +1,6 @@
 // output.cc -- manage the output file for gold
 
-// Copyright 2006, 2007 Free Software Foundation, Inc.
+// Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
 // Written by Ian Lance Taylor <iant@google.com>.
 
 // This file is part of gold.
 #include "gold.h"
 
 #include <cstdlib>
+#include <cstring>
 #include <cerrno>
 #include <fcntl.h>
 #include <unistd.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <algorithm>
-#include "libiberty.h"   // for unlink_if_ordinary()
+#include "libiberty.h"
 
 #include "parameters.h"
 #include "object.h"
 #include "symtab.h"
 #include "reloc.h"
 #include "merge.h"
+#include "descriptors.h"
 #include "output.h"
 
 // Some BSD systems still use MAP_ANON instead of MAP_ANONYMOUS
 # define MAP_ANONYMOUS  MAP_ANON
 #endif
 
+#ifndef HAVE_POSIX_FALLOCATE
+// A dummy, non general, version of posix_fallocate.  Here we just set
+// the file size and hope that there is enough disk space.  FIXME: We
+// could allocate disk space by walking block by block and writing a
+// zero byte into each block.
+static int
+posix_fallocate(int o, off_t offset, off_t len)
+{
+  return ftruncate(o, offset + len);
+}
+#endif // !defined(HAVE_POSIX_FALLOCATE)
+
 namespace gold
 {
 
@@ -61,7 +75,8 @@ Output_data::~Output_data()
 uint64_t
 Output_data::default_alignment()
 {
-  return Output_data::default_alignment_for_size(parameters->get_size());
+  return Output_data::default_alignment_for_size(
+      parameters->target().get_size());
 }
 
 // Return the default alignment for a size--32 or 64.
@@ -85,34 +100,45 @@ Output_section_headers::Output_section_headers(
     const Layout::Segment_list* segment_list,
     const Layout::Section_list* section_list,
     const Layout::Section_list* unattached_section_list,
-    const Stringpool* secnamepool)
+    const Stringpool* secnamepool,
+    const Output_section* shstrtab_section)
   : layout_(layout),
     segment_list_(segment_list),
     section_list_(section_list),
     unattached_section_list_(unattached_section_list),
-    secnamepool_(secnamepool)
+    secnamepool_(secnamepool),
+    shstrtab_section_(shstrtab_section)
+{
+}
+
+// Compute the current data size.
+
+off_t
+Output_section_headers::do_size() const
 {
   // Count all the sections.  Start with 1 for the null section.
   off_t count = 1;
-  if (!parameters->output_is_object())
+  if (!parameters->options().relocatable())
     {
-      for (Layout::Segment_list::const_iterator p = segment_list->begin();
-          p != segment_list->end();
+      for (Layout::Segment_list::const_iterator p =
+            this->segment_list_->begin();
+          p != this->segment_list_->end();
           ++p)
        if ((*p)->type() == elfcpp::PT_LOAD)
          count += (*p)->output_section_count();
     }
   else
     {
-      for (Layout::Section_list::const_iterator p = section_list->begin();
-          p != section_list->end();
+      for (Layout::Section_list::const_iterator p =
+            this->section_list_->begin();
+          p != this->section_list_->end();
           ++p)
        if (((*p)->flags() & elfcpp::SHF_ALLOC) != 0)
          ++count;
     }
-  count += unattached_section_list->size();
+  count += this->unattached_section_list_->size();
 
-  const int size = parameters->get_size();
+  const int size = parameters->target().get_size();
   int shdr_size;
   if (size == 32)
     shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
@@ -121,7 +147,7 @@ Output_section_headers::Output_section_headers(
   else
     gold_unreachable();
 
-  this->set_data_size(count * shdr_size);
+  return count * shdr_size;
 }
 
 // Write out the section headers.
@@ -129,46 +155,31 @@ Output_section_headers::Output_section_headers(
 void
 Output_section_headers::do_write(Output_file* of)
 {
-  if (parameters->get_size() == 32)
+  switch (parameters->size_and_endianness())
     {
-      if (parameters->is_big_endian())
-       {
-#ifdef HAVE_TARGET_32_BIG
-         this->do_sized_write<32, true>(of);
-#else
-         gold_unreachable();
-#endif
-       }
-      else
-       {
 #ifdef HAVE_TARGET_32_LITTLE
-         this->do_sized_write<32, false>(of);
-#else
-         gold_unreachable();
+    case Parameters::TARGET_32_LITTLE:
+      this->do_sized_write<32, false>(of);
+      break;
 #endif
-       }
-    }
-  else if (parameters->get_size() == 64)
-    {
-      if (parameters->is_big_endian())
-       {
-#ifdef HAVE_TARGET_64_BIG
-         this->do_sized_write<64, true>(of);
-#else
-         gold_unreachable();
+#ifdef HAVE_TARGET_32_BIG
+    case Parameters::TARGET_32_BIG:
+      this->do_sized_write<32, true>(of);
+      break;
 #endif
-       }
-      else
-       {
 #ifdef HAVE_TARGET_64_LITTLE
-         this->do_sized_write<64, false>(of);
-#else
-         gold_unreachable();
+    case Parameters::TARGET_64_LITTLE:
+      this->do_sized_write<64, false>(of);
+      break;
 #endif
-       }
+#ifdef HAVE_TARGET_64_BIG
+    case Parameters::TARGET_64_BIG:
+      this->do_sized_write<64, true>(of);
+      break;
+#endif
+    default:
+      gold_unreachable();
     }
-  else
-    gold_unreachable();
 }
 
 template<int size, bool big_endian>
@@ -188,9 +199,23 @@ Output_section_headers::do_sized_write(Output_file* of)
     oshdr.put_sh_flags(0);
     oshdr.put_sh_addr(0);
     oshdr.put_sh_offset(0);
-    oshdr.put_sh_size(0);
-    oshdr.put_sh_link(0);
-    oshdr.put_sh_info(0);
+
+    size_t section_count = (this->data_size()
+                           / elfcpp::Elf_sizes<size>::shdr_size);
+    if (section_count < elfcpp::SHN_LORESERVE)
+      oshdr.put_sh_size(0);
+    else
+      oshdr.put_sh_size(section_count);
+
+    unsigned int shstrndx = this->shstrtab_section_->out_shndx();
+    if (shstrndx < elfcpp::SHN_LORESERVE)
+      oshdr.put_sh_link(0);
+    else
+      oshdr.put_sh_link(shstrndx);
+
+    size_t segment_count = this->segment_list_->size();
+    oshdr.put_sh_info(segment_count >= elfcpp::PN_XNUM ? segment_count : 0);
+
     oshdr.put_sh_addralign(0);
     oshdr.put_sh_entsize(0);
   }
@@ -198,7 +223,7 @@ Output_section_headers::do_sized_write(Output_file* of)
   v += shdr_size;
 
   unsigned int shndx = 1;
-  if (!parameters->output_is_object())
+  if (!parameters->options().relocatable())
     {
       for (Layout::Segment_list::const_iterator p =
             this->segment_list_->begin();
@@ -237,7 +262,7 @@ Output_section_headers::do_sized_write(Output_file* of)
       // For a relocatable link, we did unallocated group sections
       // above, since they have to come first.
       if ((*p)->type() == elfcpp::SHT_GROUP
-         && parameters->output_is_object())
+         && parameters->options().relocatable())
        continue;
       gold_assert(shndx == (*p)->out_shndx());
       elfcpp::Shdr_write<size, big_endian> oshdr(v);
@@ -255,61 +280,36 @@ Output_segment_headers::Output_segment_headers(
     const Layout::Segment_list& segment_list)
   : segment_list_(segment_list)
 {
-  const int size = parameters->get_size();
-  int phdr_size;
-  if (size == 32)
-    phdr_size = elfcpp::Elf_sizes<32>::phdr_size;
-  else if (size == 64)
-    phdr_size = elfcpp::Elf_sizes<64>::phdr_size;
-  else
-    gold_unreachable();
-
-  this->set_data_size(segment_list.size() * phdr_size);
 }
 
 void
 Output_segment_headers::do_write(Output_file* of)
 {
-  if (parameters->get_size() == 32)
+  switch (parameters->size_and_endianness())
     {
-      if (parameters->is_big_endian())
-       {
-#ifdef HAVE_TARGET_32_BIG
-         this->do_sized_write<32, true>(of);
-#else
-         gold_unreachable();
-#endif
-       }
-      else
-       {
 #ifdef HAVE_TARGET_32_LITTLE
-       this->do_sized_write<32, false>(of);
-#else
-       gold_unreachable();
+    case Parameters::TARGET_32_LITTLE:
+      this->do_sized_write<32, false>(of);
+      break;
 #endif
-       }
-    }
-  else if (parameters->get_size() == 64)
-    {
-      if (parameters->is_big_endian())
-       {
-#ifdef HAVE_TARGET_64_BIG
-         this->do_sized_write<64, true>(of);
-#else
-         gold_unreachable();
+#ifdef HAVE_TARGET_32_BIG
+    case Parameters::TARGET_32_BIG:
+      this->do_sized_write<32, true>(of);
+      break;
 #endif
-       }
-      else
-       {
 #ifdef HAVE_TARGET_64_LITTLE
-         this->do_sized_write<64, false>(of);
-#else
-         gold_unreachable();
+    case Parameters::TARGET_64_LITTLE:
+      this->do_sized_write<64, false>(of);
+      break;
 #endif
-       }
+#ifdef HAVE_TARGET_64_BIG
+    case Parameters::TARGET_64_BIG:
+      this->do_sized_write<64, true>(of);
+      break;
+#endif
+    default:
+      gold_unreachable();
     }
-  else
-    gold_unreachable();
 }
 
 template<int size, bool big_endian>
@@ -336,6 +336,21 @@ Output_segment_headers::do_sized_write(Output_file* of)
   of->write_output_view(this->offset(), all_phdrs_size, view);
 }
 
+off_t
+Output_segment_headers::do_size() const
+{
+  const int size = parameters->target().get_size();
+  int phdr_size;
+  if (size == 32)
+    phdr_size = elfcpp::Elf_sizes<32>::phdr_size;
+  else if (size == 64)
+    phdr_size = elfcpp::Elf_sizes<64>::phdr_size;
+  else
+    gold_unreachable();
+
+  return this->segment_list_.size() * phdr_size;
+}
+
 // Output_file_header methods.
 
 Output_file_header::Output_file_header(const Target* target,
@@ -349,16 +364,7 @@ Output_file_header::Output_file_header(const Target* target,
     shstrtab_(NULL),
     entry_(entry)
 {
-  const int size = parameters->get_size();
-  int ehdr_size;
-  if (size == 32)
-    ehdr_size = elfcpp::Elf_sizes<32>::ehdr_size;
-  else if (size == 64)
-    ehdr_size = elfcpp::Elf_sizes<64>::ehdr_size;
-  else
-    gold_unreachable();
-
-  this->set_data_size(ehdr_size);
+  this->set_data_size(this->do_size());
 }
 
 // Set the section table information for a file header.
@@ -378,46 +384,31 @@ Output_file_header::do_write(Output_file* of)
 {
   gold_assert(this->offset() == 0);
 
-  if (parameters->get_size() == 32)
+  switch (parameters->size_and_endianness())
     {
-      if (parameters->is_big_endian())
-       {
-#ifdef HAVE_TARGET_32_BIG
-         this->do_sized_write<32, true>(of);
-#else
-         gold_unreachable();
-#endif
-       }
-      else
-       {
 #ifdef HAVE_TARGET_32_LITTLE
-         this->do_sized_write<32, false>(of);
-#else
-         gold_unreachable();
+    case Parameters::TARGET_32_LITTLE:
+      this->do_sized_write<32, false>(of);
+      break;
 #endif
-       }
-    }
-  else if (parameters->get_size() == 64)
-    {
-      if (parameters->is_big_endian())
-       {
-#ifdef HAVE_TARGET_64_BIG
-         this->do_sized_write<64, true>(of);
-#else
-         gold_unreachable();
+#ifdef HAVE_TARGET_32_BIG
+    case Parameters::TARGET_32_BIG:
+      this->do_sized_write<32, true>(of);
+      break;
 #endif
-       }
-      else
-       {
 #ifdef HAVE_TARGET_64_LITTLE
-         this->do_sized_write<64, false>(of);
-#else
-         gold_unreachable();
+    case Parameters::TARGET_64_LITTLE:
+      this->do_sized_write<64, false>(of);
+      break;
 #endif
-       }
+#ifdef HAVE_TARGET_64_BIG
+    case Parameters::TARGET_64_BIG:
+      this->do_sized_write<64, true>(of);
+      break;
+#endif
+    default:
+      gold_unreachable();
     }
-  else
-    gold_unreachable();
 }
 
 // Write out the file header with appropriate size and endianess.
@@ -448,13 +439,12 @@ Output_file_header::do_sized_write(Output_file* of)
                              ? elfcpp::ELFDATA2MSB
                              : elfcpp::ELFDATA2LSB);
   e_ident[elfcpp::EI_VERSION] = elfcpp::EV_CURRENT;
-  // FIXME: Some targets may need to set EI_OSABI and EI_ABIVERSION.
   oehdr.put_e_ident(e_ident);
 
   elfcpp::ET e_type;
-  if (parameters->output_is_object())
+  if (parameters->options().relocatable())
     e_type = elfcpp::ET_REL;
-  else if (parameters->output_is_shared())
+  else if (parameters->options().output_is_position_independent())
     e_type = elfcpp::ET_DYN;
   else
     e_type = elfcpp::ET_EXEC;
@@ -471,10 +461,7 @@ Output_file_header::do_sized_write(Output_file* of)
     oehdr.put_e_phoff(this->segment_header_->offset());
 
   oehdr.put_e_shoff(this->section_header_->offset());
-
-  // FIXME: The target needs to set the flags.
-  oehdr.put_e_flags(0);
-
+  oehdr.put_e_flags(this->target_->processor_specific_flags());
   oehdr.put_e_ehsize(elfcpp::Elf_sizes<size>::ehdr_size);
 
   if (this->segment_header_ == NULL)
@@ -485,14 +472,32 @@ Output_file_header::do_sized_write(Output_file* of)
   else
     {
       oehdr.put_e_phentsize(elfcpp::Elf_sizes<size>::phdr_size);
-      oehdr.put_e_phnum(this->segment_header_->data_size()
-                       / elfcpp::Elf_sizes<size>::phdr_size);
+      size_t phnum = (this->segment_header_->data_size()
+                     / elfcpp::Elf_sizes<size>::phdr_size);
+      if (phnum > elfcpp::PN_XNUM)
+       phnum = elfcpp::PN_XNUM;
+      oehdr.put_e_phnum(phnum);
     }
 
   oehdr.put_e_shentsize(elfcpp::Elf_sizes<size>::shdr_size);
-  oehdr.put_e_shnum(this->section_header_->data_size()
-                    / elfcpp::Elf_sizes<size>::shdr_size);
-  oehdr.put_e_shstrndx(this->shstrtab_->out_shndx());
+  size_t section_count = (this->section_header_->data_size()
+                         / elfcpp::Elf_sizes<size>::shdr_size);
+
+  if (section_count < elfcpp::SHN_LORESERVE)
+    oehdr.put_e_shnum(this->section_header_->data_size()
+                     / elfcpp::Elf_sizes<size>::shdr_size);
+  else
+    oehdr.put_e_shnum(0);
+
+  unsigned int shstrndx = this->shstrtab_->out_shndx();
+  if (shstrndx < elfcpp::SHN_LORESERVE)
+    oehdr.put_e_shstrndx(this->shstrtab_->out_shndx());
+  else
+    oehdr.put_e_shstrndx(elfcpp::SHN_XINDEX);
+
+  // Let the target adjust the ELF header, e.g., to set EI_OSABI in
+  // the e_ident field.
+  parameters->target().adjust_elf_header(view, ehdr_size);
 
   of->write_output_view(0, ehdr_size, view);
 }
@@ -505,7 +510,8 @@ typename elfcpp::Elf_types<size>::Elf_Addr
 Output_file_header::entry()
 {
   const bool should_issue_warning = (this->entry_ != NULL
-                                    && parameters->output_is_executable());
+                                    && !parameters->options().relocatable()
+                                     && !parameters->options().shared());
 
   // FIXME: Need to support target specific entry symbol.
   const char* entry = this->entry_;
@@ -540,6 +546,20 @@ Output_file_header::entry()
   return v;
 }
 
+// Compute the current data size.
+
+off_t
+Output_file_header::do_size() const
+{
+  const int size = parameters->target().get_size();
+  if (size == 32)
+    return elfcpp::Elf_sizes<32>::ehdr_size;
+  else if (size == 64)
+    return elfcpp::Elf_sizes<64>::ehdr_size;
+  else
+    gold_unreachable();
+}
+
 // Output_data_const methods.
 
 void
@@ -577,6 +597,18 @@ Output_section_data::do_out_shndx() const
   return this->output_section_->out_shndx();
 }
 
+// Set the alignment, which means we may need to update the alignment
+// of the output section.
+
+void
+Output_section_data::set_addralign(uint64_t addralign)
+{
+  this->addralign_ = addralign;
+  if (this->output_section_ != NULL
+      && this->output_section_->addralign() < addralign)
+    this->output_section_->set_addralign(addralign);
+}
+
 // Output_data_strtab methods.
 
 // Set the final data size.
@@ -606,32 +638,40 @@ Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
     unsigned int type,
     Output_data* od,
     Address address,
-    bool is_relative)
+    bool is_relative,
+    bool is_symbolless)
   : address_(address), local_sym_index_(GSYM_CODE), type_(type),
-    is_relative_(is_relative), shndx_(INVALID_CODE)
+    is_relative_(is_relative), is_symbolless_(is_symbolless),
+    is_section_symbol_(false), shndx_(INVALID_CODE)
 {
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
   this->u1_.gsym = gsym;
   this->u2_.od = od;
-  if (dynamic && !is_relative)
-    gsym->set_needs_dynsym_entry();
+  if (dynamic)
+    this->set_needs_dynsym_index();
 }
 
 template<bool dynamic, int size, bool big_endian>
 Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
     Symbol* gsym,
     unsigned int type,
-    Relobj* relobj,
+    Sized_relobj<size, big_endian>* relobj,
     unsigned int shndx,
     Address address,
-    bool is_relative)
+    bool is_relative,
+    bool is_symbolless)
   : address_(address), local_sym_index_(GSYM_CODE), type_(type),
-    is_relative_(is_relative), shndx_(shndx)
+    is_relative_(is_relative), is_symbolless_(is_symbolless),
+    is_section_symbol_(false), shndx_(shndx)
 {
   gold_assert(shndx != INVALID_CODE);
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
   this->u1_.gsym = gsym;
   this->u2_.relobj = relobj;
-  if (dynamic && !is_relative)
-    gsym->set_needs_dynsym_entry();
+  if (dynamic)
+    this->set_needs_dynsym_index();
 }
 
 // A reloc against a local symbol.
@@ -643,16 +683,21 @@ Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
     unsigned int type,
     Output_data* od,
     Address address,
-    bool is_relative)
+    bool is_relative,
+    bool is_symbolless,
+    bool is_section_symbol)
   : address_(address), local_sym_index_(local_sym_index), type_(type),
-    is_relative_(is_relative), shndx_(INVALID_CODE)
+    is_relative_(is_relative), is_symbolless_(is_symbolless),
+    is_section_symbol_(is_section_symbol), shndx_(INVALID_CODE)
 {
   gold_assert(local_sym_index != GSYM_CODE
               && local_sym_index != INVALID_CODE);
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
   this->u1_.relobj = relobj;
   this->u2_.od = od;
-  if (dynamic && !is_relative)
-    relobj->set_needs_output_dynsym_entry(local_sym_index);
+  if (dynamic)
+    this->set_needs_dynsym_index();
 }
 
 template<bool dynamic, int size, bool big_endian>
@@ -662,17 +707,22 @@ Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
     unsigned int type,
     unsigned int shndx,
     Address address,
-    bool is_relative)
+    bool is_relative,
+    bool is_symbolless,
+    bool is_section_symbol)
   : address_(address), local_sym_index_(local_sym_index), type_(type),
-    is_relative_(is_relative), shndx_(shndx)
+    is_relative_(is_relative), is_symbolless_(is_symbolless),
+    is_section_symbol_(is_section_symbol), shndx_(shndx)
 {
   gold_assert(local_sym_index != GSYM_CODE
               && local_sym_index != INVALID_CODE);
   gold_assert(shndx != INVALID_CODE);
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
   this->u1_.relobj = relobj;
   this->u2_.relobj = relobj;
-  if (dynamic && !is_relative)
-    relobj->set_needs_output_dynsym_entry(local_sym_index);
+  if (dynamic)
+    this->set_needs_dynsym_index();
 }
 
 // A reloc against the STT_SECTION symbol of an output section.
@@ -684,29 +734,150 @@ Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
     Output_data* od,
     Address address)
   : address_(address), local_sym_index_(SECTION_CODE), type_(type),
-    is_relative_(false), shndx_(INVALID_CODE)
+    is_relative_(false), is_symbolless_(false),
+    is_section_symbol_(true), shndx_(INVALID_CODE)
 {
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
   this->u1_.os = os;
   this->u2_.od = od;
   if (dynamic)
-    os->set_needs_dynsym_index();
+    this->set_needs_dynsym_index();
+  else
+    os->set_needs_symtab_index();
 }
 
 template<bool dynamic, int size, bool big_endian>
 Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
     Output_section* os,
     unsigned int type,
-    Relobj* relobj,
+    Sized_relobj<size, big_endian>* relobj,
     unsigned int shndx,
     Address address)
   : address_(address), local_sym_index_(SECTION_CODE), type_(type),
-    is_relative_(false), shndx_(shndx)
+    is_relative_(false), is_symbolless_(false),
+    is_section_symbol_(true), shndx_(shndx)
 {
   gold_assert(shndx != INVALID_CODE);
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
   this->u1_.os = os;
   this->u2_.relobj = relobj;
   if (dynamic)
-    os->set_needs_dynsym_index();
+    this->set_needs_dynsym_index();
+  else
+    os->set_needs_symtab_index();
+}
+
+// An absolute relocation.
+
+template<bool dynamic, int size, bool big_endian>
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
+    unsigned int type,
+    Output_data* od,
+    Address address)
+  : address_(address), local_sym_index_(0), type_(type),
+    is_relative_(false), is_symbolless_(false),
+    is_section_symbol_(false), shndx_(INVALID_CODE)
+{
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
+  this->u1_.relobj = NULL;
+  this->u2_.od = od;
+}
+
+template<bool dynamic, int size, bool big_endian>
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
+    unsigned int type,
+    Sized_relobj<size, big_endian>* relobj,
+    unsigned int shndx,
+    Address address)
+  : address_(address), local_sym_index_(0), type_(type),
+    is_relative_(false), is_symbolless_(false),
+    is_section_symbol_(false), shndx_(shndx)
+{
+  gold_assert(shndx != INVALID_CODE);
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
+  this->u1_.relobj = NULL;
+  this->u2_.relobj = relobj;
+}
+
+// A target specific relocation.
+
+template<bool dynamic, int size, bool big_endian>
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
+    unsigned int type,
+    void* arg,
+    Output_data* od,
+    Address address)
+  : address_(address), local_sym_index_(TARGET_CODE), type_(type),
+    is_relative_(false), is_symbolless_(false),
+    is_section_symbol_(false), shndx_(INVALID_CODE)
+{
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
+  this->u1_.arg = arg;
+  this->u2_.od = od;
+}
+
+template<bool dynamic, int size, bool big_endian>
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
+    unsigned int type,
+    void* arg,
+    Sized_relobj<size, big_endian>* relobj,
+    unsigned int shndx,
+    Address address)
+  : address_(address), local_sym_index_(TARGET_CODE), type_(type),
+    is_relative_(false), is_symbolless_(false),
+    is_section_symbol_(false), shndx_(shndx)
+{
+  gold_assert(shndx != INVALID_CODE);
+  // this->type_ is a bitfield; make sure TYPE fits.
+  gold_assert(this->type_ == type);
+  this->u1_.arg = arg;
+  this->u2_.relobj = relobj;
+}
+
+// Record that we need a dynamic symbol index for this relocation.
+
+template<bool dynamic, int size, bool big_endian>
+void
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::
+set_needs_dynsym_index()
+{
+  if (this->is_symbolless_)
+    return;
+  switch (this->local_sym_index_)
+    {
+    case INVALID_CODE:
+      gold_unreachable();
+
+    case GSYM_CODE:
+      this->u1_.gsym->set_needs_dynsym_entry();
+      break;
+
+    case SECTION_CODE:
+      this->u1_.os->set_needs_dynsym_index();
+      break;
+
+    case TARGET_CODE:
+      // The target must take care of this if necessary.
+      break;
+
+    case 0:
+      break;
+
+    default:
+      {
+        const unsigned int lsi = this->local_sym_index_;
+        if (!this->is_section_symbol_)
+          this->u1_.relobj->set_needs_output_dynsym_entry(lsi);
+        else
+          this->u1_.relobj->output_section(lsi)->set_needs_dynsym_index();
+      }
+      break;
+    }
 }
 
 // Get the symbol index of a relocation.
@@ -717,6 +888,8 @@ Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::get_symbol_index()
   const
 {
   unsigned int index;
+  if (this->is_symbolless_)
+    return 0;
   switch (this->local_sym_index_)
     {
     case INVALID_CODE:
@@ -738,51 +911,105 @@ Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::get_symbol_index()
        index = this->u1_.os->symtab_index();
       break;
 
+    case TARGET_CODE:
+      index = parameters->target().reloc_symbol_index(this->u1_.arg,
+                                                     this->type_);
+      break;
+
     case 0:
       // Relocations without symbols use a symbol index of 0.
       index = 0;
       break;
 
     default:
-      if (dynamic)
-        index = this->u1_.relobj->dynsym_index(this->local_sym_index_);
-      else
-       index = this->u1_.relobj->symtab_index(this->local_sym_index_);
+      {
+        const unsigned int lsi = this->local_sym_index_;
+        if (!this->is_section_symbol_)
+          {
+            if (dynamic)
+              index = this->u1_.relobj->dynsym_index(lsi);
+            else
+              index = this->u1_.relobj->symtab_index(lsi);
+          }
+        else
+          {
+            Output_section* os = this->u1_.relobj->output_section(lsi);
+            gold_assert(os != NULL);
+            if (dynamic)
+              index = os->dynsym_index();
+            else
+              index = os->symtab_index();
+          }
+      }
       break;
     }
   gold_assert(index != -1U);
   return index;
 }
 
-// Write out the offset and info fields of a Rel or Rela relocation
-// entry.
+// For a local section symbol, get the address of the offset ADDEND
+// within the input section.
 
 template<bool dynamic, int size, bool big_endian>
-template<typename Write_rel>
-void
-Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::write_rel(
-    Write_rel* wr) const
+typename elfcpp::Elf_types<size>::Elf_Addr
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::
+  local_section_offset(Addend addend) const
+{
+  gold_assert(this->local_sym_index_ != GSYM_CODE
+              && this->local_sym_index_ != SECTION_CODE
+             && this->local_sym_index_ != TARGET_CODE
+              && this->local_sym_index_ != INVALID_CODE
+             && this->local_sym_index_ != 0
+              && this->is_section_symbol_);
+  const unsigned int lsi = this->local_sym_index_;
+  Output_section* os = this->u1_.relobj->output_section(lsi);
+  gold_assert(os != NULL);
+  Address offset = this->u1_.relobj->get_output_section_offset(lsi);
+  if (offset != invalid_address)
+    return offset + addend;
+  // This is a merge section.
+  offset = os->output_address(this->u1_.relobj, lsi, addend);
+  gold_assert(offset != invalid_address);
+  return offset;
+}
+
+// Get the output address of a relocation.
+
+template<bool dynamic, int size, bool big_endian>
+typename elfcpp::Elf_types<size>::Elf_Addr
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::get_address() const
 {
   Address address = this->address_;
   if (this->shndx_ != INVALID_CODE)
     {
-      section_offset_type off;
-      Output_section* os = this->u2_.relobj->output_section(this->shndx_,
-                                                           &off);
+      Output_section* os = this->u2_.relobj->output_section(this->shndx_);
       gold_assert(os != NULL);
-      if (off != -1)
+      Address off = this->u2_.relobj->get_output_section_offset(this->shndx_);
+      if (off != invalid_address)
        address += os->address() + off;
       else
        {
          address = os->output_address(this->u2_.relobj, this->shndx_,
                                       address);
-         gold_assert(address != -1U);
+         gold_assert(address != invalid_address);
        }
     }
   else if (this->u2_.od != NULL)
     address += this->u2_.od->address();
-  wr->put_r_offset(address);
-  unsigned int sym_index = this->is_relative_ ? 0 : this->get_symbol_index();
+  return address;
+}
+
+// Write out the offset and info fields of a Rel or Rela relocation
+// entry.
+
+template<bool dynamic, int size, bool big_endian>
+template<typename Write_rel>
+void
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::write_rel(
+    Write_rel* wr) const
+{
+  wr->put_r_offset(this->get_address());
+  unsigned int sym_index = this->get_symbol_index();
   wr->put_r_info(elfcpp::elf_r_info<size>(sym_index, this->type_));
 }
 
@@ -801,32 +1028,93 @@ Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::write(
 
 template<bool dynamic, int size, bool big_endian>
 typename elfcpp::Elf_types<size>::Elf_Addr
-Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::symbol_value() const
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::symbol_value(
+    Addend addend) const
 {
   if (this->local_sym_index_ == GSYM_CODE)
     {
       const Sized_symbol<size>* sym;
       sym = static_cast<const Sized_symbol<size>*>(this->u1_.gsym);
-      return sym->value();
+      return sym->value() + addend;
     }
   gold_assert(this->local_sym_index_ != SECTION_CODE
-              && this->local_sym_index_ != INVALID_CODE);
-  const Sized_relobj<size, big_endian>* relobj = this->u1_.relobj;
-  return relobj->local_symbol_value(this->local_sym_index_);
+             && this->local_sym_index_ != TARGET_CODE
+              && this->local_sym_index_ != INVALID_CODE
+             && this->local_sym_index_ != 0
+              && !this->is_section_symbol_);
+  const unsigned int lsi = this->local_sym_index_;
+  const Symbol_value<size>* symval = this->u1_.relobj->local_symbol(lsi);
+  return symval->value(this->u1_.relobj, addend);
 }
 
-// Write out a Rela relocation.
+// Reloc comparison.  This function sorts the dynamic relocs for the
+// benefit of the dynamic linker.  First we sort all relative relocs
+// to the front.  Among relative relocs, we sort by output address.
+// Among non-relative relocs, we sort by symbol index, then by output
+// address.
 
 template<bool dynamic, int size, bool big_endian>
-void
-Output_reloc<elfcpp::SHT_RELA, dynamic, size, big_endian>::write(
-    unsigned char* pov) const
+int
+Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::
+  compare(const Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>& r2)
+    const
 {
-  elfcpp::Rela_write<size, big_endian> orel(pov);
-  this->rel_.write_rel(&orel);
+  if (this->is_relative_)
+    {
+      if (!r2.is_relative_)
+       return -1;
+      // Otherwise sort by reloc address below.
+    }
+  else if (r2.is_relative_)
+    return 1;
+  else
+    {
+      unsigned int sym1 = this->get_symbol_index();
+      unsigned int sym2 = r2.get_symbol_index();
+      if (sym1 < sym2)
+       return -1;
+      else if (sym1 > sym2)
+       return 1;
+      // Otherwise sort by reloc address.
+    }
+
+  section_offset_type addr1 = this->get_address();
+  section_offset_type addr2 = r2.get_address();
+  if (addr1 < addr2)
+    return -1;
+  else if (addr1 > addr2)
+    return 1;
+
+  // Final tie breaker, in order to generate the same output on any
+  // host: reloc type.
+  unsigned int type1 = this->type_;
+  unsigned int type2 = r2.type_;
+  if (type1 < type2)
+    return -1;
+  else if (type1 > type2)
+    return 1;
+
+  // These relocs appear to be exactly the same.
+  return 0;
+}
+
+// Write out a Rela relocation.
+
+template<bool dynamic, int size, bool big_endian>
+void
+Output_reloc<elfcpp::SHT_RELA, dynamic, size, big_endian>::write(
+    unsigned char* pov) const
+{
+  elfcpp::Rela_write<size, big_endian> orel(pov);
+  this->rel_.write_rel(&orel);
   Addend addend = this->addend_;
-  if (rel_.is_relative())
-    addend += rel_.symbol_value();
+  if (this->rel_.is_target_specific())
+    addend = parameters->target().reloc_addend(this->rel_.target_arg(),
+                                              this->rel_.type(), addend);
+  else if (this->rel_.is_symbolless())
+    addend = this->rel_.symbol_value(addend);
+  else if (this->rel_.is_local_section_symbol())
+    addend = this->rel_.local_section_offset(addend);
   orel.put_r_addend(addend);
 }
 
@@ -862,6 +1150,13 @@ Output_data_reloc_base<sh_type, dynamic, size, big_endian>::do_write(
   const off_t oview_size = this->data_size();
   unsigned char* const oview = of->get_output_view(off, oview_size);
 
+  if (this->sort_relocs())
+    {
+      gold_assert(dynamic);
+      std::sort(this->relocs_.begin(), this->relocs_.end(),
+               Sort_relocs_comparison());
+    }
+
   unsigned char* pov = oview;
   for (typename Relocs::const_iterator p = this->relocs_.begin();
        p != this->relocs_.end();
@@ -895,16 +1190,13 @@ template<int size, bool big_endian>
 Output_data_group<size, big_endian>::Output_data_group(
     Sized_relobj<size, big_endian>* relobj,
     section_size_type entry_count,
-    const elfcpp::Elf_Word* contents)
-  : Output_section_data(entry_count * 4, 4),
-    relobj_(relobj)
+    elfcpp::Elf_Word flags,
+    std::vector<unsigned int>* input_shndxes)
+  : Output_section_data(entry_count * 4, 4, false),
+    relobj_(relobj),
+    flags_(flags)
 {
-  this->flags_ = elfcpp::Swap<32, big_endian>::readval(contents);
-  for (section_size_type i = 1; i < entry_count; ++i)
-    {
-      unsigned int shndx = elfcpp::Swap<32, big_endian>::readval(contents + i);
-      this->input_sections_.push_back(shndx);
-    }
+  this->input_shndxes_.swap(*input_shndxes);
 }
 
 // Write out the section group, which means translating the section
@@ -924,12 +1216,11 @@ Output_data_group<size, big_endian>::do_write(Output_file* of)
   ++contents;
 
   for (std::vector<unsigned int>::const_iterator p =
-        this->input_sections_.begin();
-       p != this->input_sections_.end();
+        this->input_shndxes_.begin();
+       p != this->input_shndxes_.end();
        ++p, ++contents)
     {
-      section_offset_type dummy;
-      Output_section* os = this->relobj_->output_section(*p, &dummy);
+      Output_section* os = this->relobj_->output_section(*p);
 
       unsigned int output_shndx;
       if (os != NULL)
@@ -950,7 +1241,7 @@ Output_data_group<size, big_endian>::do_write(Output_file* of)
   of->write_output_view(off, oview_size, oview);
 
   // We no longer need this information.
-  this->input_sections_.clear();
+  this->input_shndxes_.clear();
 }
 
 // Output_data_got::Got_entry methods.
@@ -985,7 +1276,11 @@ Output_data_got<size, big_endian>::Got_entry::write(unsigned char* pov) const
       break;
 
     default:
-      val = this->u_.object->local_symbol_value(this->local_sym_index_);
+      {
+        const unsigned int lsi = this->local_sym_index_;
+        const Symbol_value<size>* symval = this->u_.object->local_symbol(lsi);
+        val = symval->value(this->u_.object, 0);
+      }
       break;
     }
 
@@ -1000,14 +1295,16 @@ Output_data_got<size, big_endian>::Got_entry::write(unsigned char* pov) const
 
 template<int size, bool big_endian>
 bool
-Output_data_got<size, big_endian>::add_global(Symbol* gsym)
+Output_data_got<size, big_endian>::add_global(
+    Symbol* gsym,
+    unsigned int got_type)
 {
-  if (gsym->has_got_offset())
+  if (gsym->has_got_offset(got_type))
     return false;
 
   this->entries_.push_back(Got_entry(gsym));
   this->set_got_size();
-  gsym->set_got_offset(this->last_got_offset());
+  gsym->set_got_offset(got_type, this->last_got_offset());
   return true;
 }
 
@@ -1017,16 +1314,17 @@ template<int size, bool big_endian>
 void
 Output_data_got<size, big_endian>::add_global_with_rel(
     Symbol* gsym,
+    unsigned int got_type,
     Rel_dyn* rel_dyn,
     unsigned int r_type)
 {
-  if (gsym->has_got_offset())
+  if (gsym->has_got_offset(got_type))
     return;
 
   this->entries_.push_back(Got_entry());
   this->set_got_size();
   unsigned int got_offset = this->last_got_offset();
-  gsym->set_got_offset(got_offset);
+  gsym->set_got_offset(got_type, got_offset);
   rel_dyn->add_global(gsym, r_type, this, got_offset);
 }
 
@@ -1034,260 +1332,196 @@ template<int size, bool big_endian>
 void
 Output_data_got<size, big_endian>::add_global_with_rela(
     Symbol* gsym,
+    unsigned int got_type,
     Rela_dyn* rela_dyn,
     unsigned int r_type)
 {
-  if (gsym->has_got_offset())
+  if (gsym->has_got_offset(got_type))
     return;
 
   this->entries_.push_back(Got_entry());
   this->set_got_size();
   unsigned int got_offset = this->last_got_offset();
-  gsym->set_got_offset(got_offset);
+  gsym->set_got_offset(got_type, got_offset);
   rela_dyn->add_global(gsym, r_type, this, got_offset, 0);
 }
 
-// Add an entry for a local symbol to the GOT.  This returns true if
-// this is a new GOT entry, false if the symbol already has a GOT
-// entry.
-
-template<int size, bool big_endian>
-bool
-Output_data_got<size, big_endian>::add_local(
-    Sized_relobj<size, big_endian>* object,
-    unsigned int symndx)
-{
-  if (object->local_has_got_offset(symndx))
-    return false;
-
-  this->entries_.push_back(Got_entry(object, symndx));
-  this->set_got_size();
-  object->set_local_got_offset(symndx, this->last_got_offset());
-  return true;
-}
-
-// Add an entry for a local symbol to the GOT, and add a dynamic
-// relocation of type R_TYPE for the GOT entry.
+// Add a pair of entries for a global symbol to the GOT, and add
+// dynamic relocations of type R_TYPE_1 and R_TYPE_2, respectively.
+// If R_TYPE_2 == 0, add the second entry with no relocation.
 template<int size, bool big_endian>
 void
-Output_data_got<size, big_endian>::add_local_with_rel(
-    Sized_relobj<size, big_endian>* object,
-    unsigned int symndx,
+Output_data_got<size, big_endian>::add_global_pair_with_rel(
+    Symbol* gsym,
+    unsigned int got_type,
     Rel_dyn* rel_dyn,
-    unsigned int r_type)
+    unsigned int r_type_1,
+    unsigned int r_type_2)
 {
-  if (object->local_has_got_offset(symndx))
+  if (gsym->has_got_offset(got_type))
     return;
 
   this->entries_.push_back(Got_entry());
-  this->set_got_size();
   unsigned int got_offset = this->last_got_offset();
-  object->set_local_got_offset(symndx, got_offset);
-  rel_dyn->add_local(object, symndx, r_type, this, got_offset);
+  gsym->set_got_offset(got_type, got_offset);
+  rel_dyn->add_global(gsym, r_type_1, this, got_offset);
+
+  this->entries_.push_back(Got_entry());
+  if (r_type_2 != 0)
+    {
+      got_offset = this->last_got_offset();
+      rel_dyn->add_global(gsym, r_type_2, this, got_offset);
+    }
+
+  this->set_got_size();
 }
 
 template<int size, bool big_endian>
 void
-Output_data_got<size, big_endian>::add_local_with_rela(
-    Sized_relobj<size, big_endian>* object,
-    unsigned int symndx,
+Output_data_got<size, big_endian>::add_global_pair_with_rela(
+    Symbol* gsym,
+    unsigned int got_type,
     Rela_dyn* rela_dyn,
-    unsigned int r_type)
+    unsigned int r_type_1,
+    unsigned int r_type_2)
 {
-  if (object->local_has_got_offset(symndx))
+  if (gsym->has_got_offset(got_type))
     return;
 
   this->entries_.push_back(Got_entry());
-  this->set_got_size();
   unsigned int got_offset = this->last_got_offset();
-  object->set_local_got_offset(symndx, got_offset);
-  rela_dyn->add_local(object, symndx, r_type, this, got_offset, 0);
+  gsym->set_got_offset(got_type, got_offset);
+  rela_dyn->add_global(gsym, r_type_1, this, got_offset, 0);
+
+  this->entries_.push_back(Got_entry());
+  if (r_type_2 != 0)
+    {
+      got_offset = this->last_got_offset();
+      rela_dyn->add_global(gsym, r_type_2, this, got_offset, 0);
+    }
+
+  this->set_got_size();
 }
 
-// Add an entry (or a pair of entries) for a global TLS symbol to the GOT.
-// In a pair of entries, the first value in the pair will be used for the
-// module index, and the second value will be used for the dtv-relative
-// offset. This returns true if this is a new GOT entry, false if the symbol
-// already has a GOT entry.
+// Add an entry for a local symbol to the GOT.  This returns true if
+// this is a new GOT entry, false if the symbol already has a GOT
+// entry.
 
 template<int size, bool big_endian>
 bool
-Output_data_got<size, big_endian>::add_global_tls(Symbol* gsym, bool need_pair)
+Output_data_got<size, big_endian>::add_local(
+    Sized_relobj<size, big_endian>* object,
+    unsigned int symndx,
+    unsigned int got_type)
 {
-  if (gsym->has_tls_got_offset(need_pair))
+  if (object->local_has_got_offset(symndx, got_type))
     return false;
 
-  this->entries_.push_back(Got_entry(gsym));
-  gsym->set_tls_got_offset(this->last_got_offset(), need_pair);
-  if (need_pair)
-    this->entries_.push_back(Got_entry(gsym));
+  this->entries_.push_back(Got_entry(object, symndx));
   this->set_got_size();
+  object->set_local_got_offset(symndx, got_type, this->last_got_offset());
   return true;
 }
 
-// Add an entry for a global TLS symbol to the GOT, and add a dynamic
-// relocation of type R_TYPE.
+// Add an entry for a local symbol to the GOT, and add a dynamic
+// relocation of type R_TYPE for the GOT entry.
 template<int size, bool big_endian>
 void
-Output_data_got<size, big_endian>::add_global_tls_with_rel(
-    Symbol* gsym,
+Output_data_got<size, big_endian>::add_local_with_rel(
+    Sized_relobj<size, big_endian>* object,
+    unsigned int symndx,
+    unsigned int got_type,
     Rel_dyn* rel_dyn,
     unsigned int r_type)
 {
-  if (gsym->has_tls_got_offset(false))
+  if (object->local_has_got_offset(symndx, got_type))
     return;
 
   this->entries_.push_back(Got_entry());
   this->set_got_size();
   unsigned int got_offset = this->last_got_offset();
-  gsym->set_tls_got_offset(got_offset, false);
-  rel_dyn->add_global(gsym, r_type, this, got_offset);
+  object->set_local_got_offset(symndx, got_type, got_offset);
+  rel_dyn->add_local(object, symndx, r_type, this, got_offset);
 }
 
 template<int size, bool big_endian>
 void
-Output_data_got<size, big_endian>::add_global_tls_with_rela(
-    Symbol* gsym,
+Output_data_got<size, big_endian>::add_local_with_rela(
+    Sized_relobj<size, big_endian>* object,
+    unsigned int symndx,
+    unsigned int got_type,
     Rela_dyn* rela_dyn,
     unsigned int r_type)
 {
-  if (gsym->has_tls_got_offset(false))
-    return;
-
-  this->entries_.push_back(Got_entry());
-  this->set_got_size();
-  unsigned int got_offset = this->last_got_offset();
-  gsym->set_tls_got_offset(got_offset, false);
-  rela_dyn->add_global(gsym, r_type, this, got_offset, 0);
-}
-
-// Add a pair of entries for a global TLS symbol to the GOT, and add
-// dynamic relocations of type MOD_R_TYPE and DTV_R_TYPE, respectively.
-template<int size, bool big_endian>
-void
-Output_data_got<size, big_endian>::add_global_tls_with_rel(
-    Symbol* gsym,
-    Rel_dyn* rel_dyn,
-    unsigned int mod_r_type,
-    unsigned int dtv_r_type)
-{
-  if (gsym->has_tls_got_offset(true))
+  if (object->local_has_got_offset(symndx, got_type))
     return;
 
-  this->entries_.push_back(Got_entry());
-  unsigned int got_offset = this->last_got_offset();
-  gsym->set_tls_got_offset(got_offset, true);
-  rel_dyn->add_global(gsym, mod_r_type, this, got_offset);
-
   this->entries_.push_back(Got_entry());
   this->set_got_size();
-  got_offset = this->last_got_offset();
-  rel_dyn->add_global(gsym, dtv_r_type, this, got_offset);
-}
-
-template<int size, bool big_endian>
-void
-Output_data_got<size, big_endian>::add_global_tls_with_rela(
-    Symbol* gsym,
-    Rela_dyn* rela_dyn,
-    unsigned int mod_r_type,
-    unsigned int dtv_r_type)
-{
-  if (gsym->has_tls_got_offset(true))
-    return;
-
-  this->entries_.push_back(Got_entry());
   unsigned int got_offset = this->last_got_offset();
-  gsym->set_tls_got_offset(got_offset, true);
-  rela_dyn->add_global(gsym, mod_r_type, this, got_offset, 0);
-
-  this->entries_.push_back(Got_entry());
-  this->set_got_size();
-  got_offset = this->last_got_offset();
-  rela_dyn->add_global(gsym, dtv_r_type, this, got_offset, 0);
-}
-
-// Add an entry (or a pair of entries) for a local TLS symbol to the GOT.
-// In a pair of entries, the first value in the pair will be used for the
-// module index, and the second value will be used for the dtv-relative
-// offset. This returns true if this is a new GOT entry, false if the symbol
-// already has a GOT entry.
-
-template<int size, bool big_endian>
-bool
-Output_data_got<size, big_endian>::add_local_tls(
-    Sized_relobj<size, big_endian>* object,
-    unsigned int symndx,
-    bool need_pair)
-{
-  if (object->local_has_tls_got_offset(symndx, need_pair))
-    return false;
-
-  this->entries_.push_back(Got_entry(object, symndx));
-  object->set_local_tls_got_offset(symndx, this->last_got_offset(), need_pair);
-  if (need_pair)
-    this->entries_.push_back(Got_entry(object, symndx));
-  this->set_got_size();
-  return true;
+  object->set_local_got_offset(symndx, got_type, got_offset);
+  rela_dyn->add_local(object, symndx, r_type, this, got_offset, 0);
 }
 
-// Add an entry (or pair of entries) for a local TLS symbol to the GOT,
-// and add a dynamic relocation of type R_TYPE for the first GOT entry.
-// Because this is a local symbol, the first GOT entry can be relocated
-// relative to a section symbol, and the second GOT entry will have an
-// dtv-relative value that can be computed at link time.
+// Add a pair of entries for a local symbol to the GOT, and add
+// dynamic relocations of type R_TYPE_1 and R_TYPE_2, respectively.
+// If R_TYPE_2 == 0, add the second entry with no relocation.
 template<int size, bool big_endian>
 void
-Output_data_got<size, big_endian>::add_local_tls_with_rel(
+Output_data_got<size, big_endian>::add_local_pair_with_rel(
     Sized_relobj<size, big_endian>* object,
     unsigned int symndx,
     unsigned int shndx,
-    bool need_pair,
+    unsigned int got_type,
     Rel_dyn* rel_dyn,
-    unsigned int r_type)
+    unsigned int r_type_1,
+    unsigned int r_type_2)
 {
-  if (object->local_has_tls_got_offset(symndx, need_pair))
+  if (object->local_has_got_offset(symndx, got_type))
     return;
 
   this->entries_.push_back(Got_entry());
   unsigned int got_offset = this->last_got_offset();
-  object->set_local_tls_got_offset(symndx, got_offset, need_pair);
-  section_offset_type off;
-  Output_section* os = object->output_section(shndx, &off);
-  rel_dyn->add_output_section(os, r_type, this, got_offset);
+  object->set_local_got_offset(symndx, got_type, got_offset);
+  Output_section* os = object->output_section(shndx);
+  rel_dyn->add_output_section(os, r_type_1, this, got_offset);
 
-  // The second entry of the pair will be statically initialized
-  // with the TLS offset of the symbol.
-  if (need_pair)
-    this->entries_.push_back(Got_entry(object, symndx));
+  this->entries_.push_back(Got_entry(object, symndx));
+  if (r_type_2 != 0)
+    {
+      got_offset = this->last_got_offset();
+      rel_dyn->add_output_section(os, r_type_2, this, got_offset);
+    }
 
   this->set_got_size();
 }
 
 template<int size, bool big_endian>
 void
-Output_data_got<size, big_endian>::add_local_tls_with_rela(
+Output_data_got<size, big_endian>::add_local_pair_with_rela(
     Sized_relobj<size, big_endian>* object,
     unsigned int symndx,
     unsigned int shndx,
-    bool need_pair,
+    unsigned int got_type,
     Rela_dyn* rela_dyn,
-    unsigned int r_type)
+    unsigned int r_type_1,
+    unsigned int r_type_2)
 {
-  if (object->local_has_tls_got_offset(symndx, need_pair))
+  if (object->local_has_got_offset(symndx, got_type))
     return;
 
   this->entries_.push_back(Got_entry());
   unsigned int got_offset = this->last_got_offset();
-  object->set_local_tls_got_offset(symndx, got_offset, need_pair);
-  section_offset_type off;
-  Output_section* os = object->output_section(shndx, &off);
-  rela_dyn->add_output_section(os, r_type, this, got_offset, 0);
+  object->set_local_got_offset(symndx, got_type, got_offset);
+  Output_section* os = object->output_section(shndx);
+  rela_dyn->add_output_section(os, r_type_1, this, got_offset, 0);
 
-  // The second entry of the pair will be statically initialized
-  // with the TLS offset of the symbol.
-  if (need_pair)
-    this->entries_.push_back(Got_entry(object, symndx));
+  this->entries_.push_back(Got_entry(object, symndx));
+  if (r_type_2 != 0)
+    {
+      got_offset = this->last_got_offset();
+      rela_dyn->add_output_section(os, r_type_2, this, got_offset, 0);
+    }
 
   this->set_got_size();
 }
@@ -1329,22 +1563,19 @@ template<int size, bool big_endian>
 void
 Output_data_dynamic::Dynamic_entry::write(
     unsigned char* pov,
-    const Stringpool* pool
-    ACCEPT_SIZE_ENDIAN) const
+    const Stringpool* pool) const
 {
   typename elfcpp::Elf_types<size>::Elf_WXword val;
-  switch (this->classification_)
+  switch (this->offset_)
     {
     case DYNAMIC_NUMBER:
       val = this->u_.val;
       break;
 
-    case DYNAMIC_SECTION_ADDRESS:
-      val = this->u_.od->address();
-      break;
-
     case DYNAMIC_SECTION_SIZE:
       val = this->u_.od->data_size();
+      if (this->od2 != NULL)
+       val += this->od2->data_size();
       break;
 
     case DYNAMIC_SYMBOL:
@@ -1360,7 +1591,8 @@ Output_data_dynamic::Dynamic_entry::write(
       break;
 
     default:
-      gold_unreachable();
+      val = this->u_.od->address() + this->offset_;
+      break;
     }
 
   elfcpp::Dyn_write<size, big_endian> dw(pov);
@@ -1375,9 +1607,9 @@ Output_data_dynamic::Dynamic_entry::write(
 void
 Output_data_dynamic::do_adjust_output_section(Output_section* os)
 {
-  if (parameters->get_size() == 32)
+  if (parameters->target().get_size() == 32)
     os->set_entsize(elfcpp::Elf_sizes<32>::dyn_size);
-  else if (parameters->get_size() == 64)
+  else if (parameters->target().get_size() == 64)
     os->set_entsize(elfcpp::Elf_sizes<64>::dyn_size);
   else
     gold_unreachable();
@@ -1388,13 +1620,20 @@ Output_data_dynamic::do_adjust_output_section(Output_section* os)
 void
 Output_data_dynamic::set_final_data_size()
 {
-  // Add the terminating entry.
-  this->add_constant(elfcpp::DT_NULL, 0);
+  // Add the terminating entry if it hasn't been added.
+  // Because of relaxation, we can run this multiple times.
+  if (this->entries_.empty() || this->entries_.back().tag() != elfcpp::DT_NULL)
+    {
+      int extra = parameters->options().spare_dynamic_tags();
+      for (int i = 0; i < extra; ++i)
+       this->add_constant(elfcpp::DT_NULL, 0);
+      this->add_constant(elfcpp::DT_NULL, 0);
+    }
 
   int dyn_size;
-  if (parameters->get_size() == 32)
+  if (parameters->target().get_size() == 32)
     dyn_size = elfcpp::Elf_sizes<32>::dyn_size;
-  else if (parameters->get_size() == 64)
+  else if (parameters->target().get_size() == 64)
     dyn_size = elfcpp::Elf_sizes<64>::dyn_size;
   else
     gold_unreachable();
@@ -1406,46 +1645,31 @@ Output_data_dynamic::set_final_data_size()
 void
 Output_data_dynamic::do_write(Output_file* of)
 {
-  if (parameters->get_size() == 32)
+  switch (parameters->size_and_endianness())
     {
-      if (parameters->is_big_endian())
-       {
-#ifdef HAVE_TARGET_32_BIG
-         this->sized_write<32, true>(of);
-#else
-         gold_unreachable();
-#endif
-       }
-      else
-       {
 #ifdef HAVE_TARGET_32_LITTLE
-         this->sized_write<32, false>(of);
-#else
-         gold_unreachable();
+    case Parameters::TARGET_32_LITTLE:
+      this->sized_write<32, false>(of);
+      break;
 #endif
-       }
-    }
-  else if (parameters->get_size() == 64)
-    {
-      if (parameters->is_big_endian())
-       {
-#ifdef HAVE_TARGET_64_BIG
-         this->sized_write<64, true>(of);
-#else
-         gold_unreachable();
+#ifdef HAVE_TARGET_32_BIG
+    case Parameters::TARGET_32_BIG:
+      this->sized_write<32, true>(of);
+      break;
 #endif
-       }
-      else
-       {
 #ifdef HAVE_TARGET_64_LITTLE
-         this->sized_write<64, false>(of);
-#else
-         gold_unreachable();
+    case Parameters::TARGET_64_LITTLE:
+      this->sized_write<64, false>(of);
+      break;
 #endif
-       }
+#ifdef HAVE_TARGET_64_BIG
+    case Parameters::TARGET_64_BIG:
+      this->sized_write<64, true>(of);
+      break;
+#endif
+    default:
+      gold_unreachable();
     }
-  else
-    gold_unreachable();
 }
 
 template<int size, bool big_endian>
@@ -1463,8 +1687,7 @@ Output_data_dynamic::sized_write(Output_file* of)
        p != this->entries_.end();
        ++p)
     {
-      p->write SELECT_SIZE_ENDIAN_NAME(size, big_endian)(
-          pov, this->pool_ SELECT_SIZE_ENDIAN(size, big_endian));
+      p->write<size, big_endian>(pov, this->pool_);
       pov += dyn_size;
     }
 
@@ -1476,6 +1699,42 @@ Output_data_dynamic::sized_write(Output_file* of)
   this->entries_.clear();
 }
 
+// Class Output_symtab_xindex.
+
+void
+Output_symtab_xindex::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);
+
+  memset(oview, 0, oview_size);
+
+  if (parameters->target().is_big_endian())
+    this->endian_do_write<true>(oview);
+  else
+    this->endian_do_write<false>(oview);
+
+  of->write_output_view(offset, oview_size, oview);
+
+  // We no longer need the data.
+  this->entries_.clear();
+}
+
+template<bool big_endian>
+void
+Output_symtab_xindex::endian_do_write(unsigned char* const oview)
+{
+  for (Xindex_entries::const_iterator p = this->entries_.begin();
+       p != this->entries_.end();
+       ++p)
+    {
+      unsigned int symndx = p->first;
+      gold_assert(symndx * 4 < this->data_size());
+      elfcpp::Swap<32, big_endian>::writeval(oview + symndx * 4, p->second);
+    }
+}
+
 // Output_section::Input_section methods.
 
 // Return the data size.  For an input section we store the size here.
@@ -1490,6 +1749,42 @@ Output_section::Input_section::data_size() const
     return this->u2_.posd->data_size();
 }
 
+// Return the object for an input section.
+
+Relobj*
+Output_section::Input_section::relobj() const
+{
+  if (this->is_input_section())
+    return this->u2_.object;
+  else if (this->is_merge_section())
+    {
+      gold_assert(this->u2_.pomb->first_relobj() != NULL);
+      return this->u2_.pomb->first_relobj();
+    }
+  else if (this->is_relaxed_input_section())
+    return this->u2_.poris->relobj();
+  else
+    gold_unreachable();
+}
+
+// Return the input section index for an input section.
+
+unsigned int
+Output_section::Input_section::shndx() const
+{
+  if (this->is_input_section())
+    return this->shndx_;
+  else if (this->is_merge_section())
+    {
+      gold_assert(this->u2_.pomb->first_relobj() != NULL);
+      return this->u2_.pomb->first_shndx();
+    }
+  else if (this->is_relaxed_input_section())
+    return this->u2_.poris->shndx();
+  else
+    gold_unreachable();
+}
+
 // Set the address and file offset.
 
 void
@@ -1578,6 +1873,33 @@ Output_section::Input_section::write_to_buffer(unsigned char* buffer)
     this->u2_.posd->write_to_buffer(buffer);
 }
 
+// Print to a map file.
+
+void
+Output_section::Input_section::print_to_mapfile(Mapfile* mapfile) const
+{
+  switch (this->shndx_)
+    {
+    case OUTPUT_SECTION_CODE:
+    case MERGE_DATA_SECTION_CODE:
+    case MERGE_STRING_SECTION_CODE:
+      this->u2_.posd->print_to_mapfile(mapfile);
+      break;
+
+    case RELAXED_INPUT_SECTION_CODE:
+      {
+        Output_relaxed_input_section* relaxed_section =
+         this->relaxed_input_section();
+        mapfile->print_input_section(relaxed_section->relobj(),
+                                    relaxed_section->shndx());
+      }
+      break;
+    default:
+      mapfile->print_input_section(this->u2_.object, this->shndx_);
+      break;
+    }
+}
+
 // Output_section methods.
 
 // Construct an Output_section.  NAME will point into a Stringpool.
@@ -1611,7 +1933,26 @@ Output_section::Output_section(const char* name, elfcpp::Elf_Word type,
     found_in_sections_clause_(false),
     has_load_address_(false),
     info_uses_section_index_(false),
-    tls_offset_(0)
+    input_section_order_specified_(false),
+    may_sort_attached_input_sections_(false),
+    must_sort_attached_input_sections_(false),
+    attached_input_sections_are_sorted_(false),
+    is_relro_(false),
+    is_relro_local_(false),
+    is_last_relro_(false),
+    is_first_non_relro_(false),
+    is_small_section_(false),
+    is_large_section_(false),
+    is_interp_(false),
+    is_dynamic_linker_section_(false),
+    generate_code_fills_at_write_(false),
+    is_entsize_zero_(false),
+    section_offsets_need_adjustment_(false),
+    is_noload_(false),
+    always_keeps_input_sections_(false),
+    tls_offset_(0),
+    checkpoint_(NULL),
+    lookup_maps_(new Output_section_lookup_maps)
 {
   // An unallocated section has no address.  Forcing this means that
   // we don't need special treatment for symbols defined in debug
@@ -1622,6 +1963,7 @@ Output_section::Output_section(const char* name, elfcpp::Elf_Word type,
 
 Output_section::~Output_section()
 {
+  delete this->checkpoint_;
 }
 
 // Set the entry size.
@@ -1629,10 +1971,15 @@ Output_section::~Output_section()
 void
 Output_section::set_entsize(uint64_t v)
 {
-  if (this->entsize_ == 0)
+  if (this->is_entsize_zero_)
+    ;
+  else if (this->entsize_ == 0)
     this->entsize_ = v;
-  else
-    gold_assert(this->entsize_ == v);
+  else if (this->entsize_ != v)
+    {
+      this->entsize_ = 0;
+      this->is_entsize_zero_ = 1;
+    }
 }
 
 // Add the input section SHNDX, with header SHDR, named SECNAME, in
@@ -1649,7 +1996,8 @@ Output_section::set_entsize(uint64_t v)
 
 template<int size, bool big_endian>
 off_t
-Output_section::add_input_section(Sized_relobj<size, big_endian>* object,
+Output_section::add_input_section(Layout* layout,
+                                 Sized_relobj<size, big_endian>* object,
                                  unsigned int shndx,
                                  const char* secname,
                                  const elfcpp::Shdr<size, big_endian>& shdr,
@@ -1668,11 +2016,6 @@ Output_section::add_input_section(Sized_relobj<size, big_endian>* object,
     this->addralign_ = addralign;
 
   typename elfcpp::Elf_types<size>::Elf_WXword sh_flags = shdr.get_sh_flags();
-  this->flags_ |= (sh_flags
-                  & (elfcpp::SHF_WRITE
-                     | elfcpp::SHF_ALLOC
-                     | elfcpp::SHF_EXECINSTR));
-
   uint64_t entsize = shdr.get_sh_entsize();
 
   // .debug_str is a mergeable string section, but is not always so
@@ -1683,14 +2026,25 @@ Output_section::add_input_section(Sized_relobj<size, big_endian>* object,
       entsize = 1;
     }
 
+  this->update_flags_for_input_section(sh_flags);
+  this->set_entsize(entsize);
+
   // If this is a SHF_MERGE section, we pass all the input sections to
   // a Output_data_merge.  We don't try to handle relocations for such
-  // a section.
+  // a section.  We don't try to handle empty merge sections--they
+  // mess up the mappings, and are useless anyhow.
   if ((sh_flags & elfcpp::SHF_MERGE) != 0
-      && reloc_shndx == 0)
+      && reloc_shndx == 0
+      && shdr.get_sh_size() > 0)
     {
-      if (this->add_merge_input_section(object, shndx, sh_flags,
-                                       entsize, addralign))
+      // Keep information about merged input sections for rebuilding fast
+      // lookup maps if we have sections-script or we do relaxation.
+      bool keeps_input_sections = (this->always_keeps_input_sections_
+                                  || have_sections_script
+                                  || parameters->target().may_relax());
+
+      if (this->add_merge_input_section(object, shndx, sh_flags, entsize,
+                                       addralign, keeps_input_sections))
        {
          // Tell the relocation routines that they need to call the
          // output_offset method to determine the final address.
@@ -1702,10 +2056,24 @@ Output_section::add_input_section(Sized_relobj<size, big_endian>* object,
   off_t aligned_offset_in_section = align_address(offset_in_section,
                                                   addralign);
 
+  // Determine if we want to delay code-fill generation until the output
+  // section is written.  When the target is relaxing, we want to delay fill
+  // generating to avoid adjusting them during relaxation.
+  if (!this->generate_code_fills_at_write_
+      && !have_sections_script
+      && (sh_flags & elfcpp::SHF_EXECINSTR) != 0
+      && parameters->target().has_code_fill()
+      && parameters->target().may_relax())
+    {
+      gold_assert(this->fills_.empty());
+      this->generate_code_fills_at_write_ = true;
+    }
+
   if (aligned_offset_in_section > offset_in_section
+      && !this->generate_code_fills_at_write_
       && !have_sections_script
       && (sh_flags & elfcpp::SHF_EXECINSTR) != 0
-      && object->target()->has_code_fill())
+      && parameters->target().has_code_fill())
     {
       // We need to add some fill data.  Using fill_list_ when
       // possible is an optimization, since we will often have fill
@@ -1715,24 +2083,48 @@ Output_section::add_input_section(Sized_relobj<size, big_endian>* object,
         this->fills_.push_back(Fill(offset_in_section, fill_len));
       else
         {
-          // FIXME: When relaxing, the size needs to adjust to
-          // maintain a constant alignment.
-          std::string fill_data(object->target()->code_fill(fill_len));
+          std::string fill_data(parameters->target().code_fill(fill_len));
           Output_data_const* odc = new Output_data_const(fill_data, 1);
           this->input_sections_.push_back(Input_section(odc));
         }
     }
 
+  section_size_type input_section_size = shdr.get_sh_size();
+  section_size_type uncompressed_size;
+  if (object->section_is_compressed(shndx, &uncompressed_size))
+    input_section_size = uncompressed_size;
+
   this->set_current_data_size_for_child(aligned_offset_in_section
-                                       + shdr.get_sh_size());
+                                       + input_section_size);
 
   // We need to keep track of this section if we are already keeping
-  // track of sections, or if we are relaxing.  FIXME: Add test for
-  // relaxing.
-  if (have_sections_script || !this->input_sections_.empty())
-    this->input_sections_.push_back(Input_section(object, shndx,
-                                                 shdr.get_sh_size(),
-                                                 addralign));
+  // track of sections, or if we are relaxing.  Also, if this is a
+  // section which requires sorting, or which may require sorting in
+  // the future, we keep track of the sections.  If the
+  // --section-ordering-file option is used to specify the order of
+  // sections, we need to keep track of sections.
+  if (this->always_keeps_input_sections_
+      || have_sections_script
+      || !this->input_sections_.empty()
+      || this->may_sort_attached_input_sections()
+      || this->must_sort_attached_input_sections()
+      || parameters->options().user_set_Map()
+      || parameters->target().may_relax()
+      || parameters->options().section_ordering_file())
+    {
+      Input_section isecn(object, shndx, shdr.get_sh_size(), addralign);
+      if (parameters->options().section_ordering_file())
+        {
+          unsigned int section_order_index =
+            layout->find_section_order_index(std::string(secname));
+         if (section_order_index != 0)
+            {
+              isecn.set_section_order_index(section_order_index);
+              this->set_input_section_order_specified();
+            }
+        }
+      this->input_sections_.push_back(isecn);
+    }
 
   return aligned_offset_in_section;
 }
@@ -1755,17 +2147,40 @@ Output_section::add_output_section_data(Output_section_data* posd)
     }
 }
 
-// Add arbitrary data to an output section by Input_section.
+// Add a relaxed input section.
 
 void
-Output_section::add_output_section_data(Input_section* inp)
+Output_section::add_relaxed_input_section(Output_relaxed_input_section* poris)
 {
-  if (this->input_sections_.empty())
-    this->first_input_offset_ = this->current_data_size_for_child();
-
-  this->input_sections_.push_back(*inp);
-
-  uint64_t addralign = inp->addralign();
+  Input_section inp(poris);
+  this->add_output_section_data(&inp);
+  if (this->lookup_maps_->is_valid())
+    this->lookup_maps_->add_relaxed_input_section(poris->relobj(),
+                                                 poris->shndx(), poris);
+
+  // For a relaxed section, we use the current data size.  Linker scripts
+  // get all the input sections, including relaxed one from an output
+  // section and add them back to them same output section to compute the
+  // output section size.  If we do not account for sizes of relaxed input
+  // sections,  an output section would be incorrectly sized.
+  off_t offset_in_section = this->current_data_size_for_child();
+  off_t aligned_offset_in_section = align_address(offset_in_section,
+                                                 poris->addralign());
+  this->set_current_data_size_for_child(aligned_offset_in_section
+                                       + poris->current_data_size());
+}
+
+// Add arbitrary data to an output section by Input_section.
+
+void
+Output_section::add_output_section_data(Input_section* inp)
+{
+  if (this->input_sections_.empty())
+    this->first_input_offset_ = this->current_data_size_for_child();
+
+  this->input_sections_.push_back(*inp);
+
+  uint64_t addralign = inp->addralign();
   if (addralign > this->addralign_)
     this->addralign_ = addralign;
 
@@ -1787,7 +2202,8 @@ Output_section::add_output_merge_section(Output_section_data* posd,
 bool
 Output_section::add_merge_input_section(Relobj* object, unsigned int shndx,
                                        uint64_t flags, uint64_t entsize,
-                                       uint64_t addralign)
+                                       uint64_t addralign,
+                                       bool keeps_input_sections)
 {
   bool is_string = (flags & elfcpp::SHF_STRINGS) != 0;
 
@@ -1796,43 +2212,272 @@ Output_section::add_merge_input_section(Relobj* object, unsigned int shndx,
   if (is_string && addralign > entsize)
     return false;
 
-  Input_section_list::iterator p;
-  for (p = this->input_sections_.begin();
-       p != this->input_sections_.end();
-       ++p)
-    if (p->is_merge_section(is_string, entsize, addralign))
+  // We cannot restore merged input section states.
+  gold_assert(this->checkpoint_ == NULL);
+
+  // Look up merge sections by required properties.
+  // Currently, we only invalidate the lookup maps in script processing
+  // and relaxation.  We should not have done either when we reach here.
+  // So we assume that the lookup maps are valid to simply code.
+  gold_assert(this->lookup_maps_->is_valid());
+  Merge_section_properties msp(is_string, entsize, addralign);
+  Output_merge_base* pomb = this->lookup_maps_->find_merge_section(msp);
+  bool is_new = false;
+  if (pomb != NULL)
+    {
+      gold_assert(pomb->is_string() == is_string
+                 && pomb->entsize() == entsize
+                 && pomb->addralign() == addralign);
+    }
+  else
+    {
+      // Create a new Output_merge_data or Output_merge_string_data.
+      if (!is_string)
+       pomb = new Output_merge_data(entsize, addralign);
+      else
+       {
+         switch (entsize)
+           {
+           case 1:
+             pomb = new Output_merge_string<char>(addralign);
+             break;
+           case 2:
+             pomb = new Output_merge_string<uint16_t>(addralign);
+             break;
+           case 4:
+             pomb = new Output_merge_string<uint32_t>(addralign);
+             break;
+           default:
+             return false;
+           }
+       }
+      // If we need to do script processing or relaxation, we need to keep
+      // the original input sections to rebuild the fast lookup maps.
+      if (keeps_input_sections)
+       pomb->set_keeps_input_sections();
+      is_new = true;
+    }
+
+  if (pomb->add_input_section(object, shndx))
+    {
+      // Add new merge section to this output section and link merge
+      // section properties to new merge section in map.
+      if (is_new)
+       {
+         this->add_output_merge_section(pomb, is_string, entsize);
+         this->lookup_maps_->add_merge_section(msp, pomb);
+       }
+
+      // Add input section to new merge section and link input section to new
+      // merge section in map.
+      this->lookup_maps_->add_merge_input_section(object, shndx, pomb);
+      return true;
+    }
+  else
+    {
+      // If add_input_section failed, delete new merge section to avoid
+      // exporting empty merge sections in Output_section::get_input_section.
+      if (is_new)
+       delete pomb;
+      return false;
+    }
+}
+
+// Build a relaxation map to speed up relaxation of existing input sections.
+// Look up to the first LIMIT elements in INPUT_SECTIONS.
+
+void
+Output_section::build_relaxation_map(
+  const Input_section_list& input_sections,
+  size_t limit,
+  Relaxation_map* relaxation_map) const
+{
+  for (size_t i = 0; i < limit; ++i)
+    {
+      const Input_section& is(input_sections[i]);
+      if (is.is_input_section() || is.is_relaxed_input_section())
+       {
+         Section_id sid(is.relobj(), is.shndx());
+         (*relaxation_map)[sid] = i;
+       }
+    }
+}
+
+// Convert regular input sections in INPUT_SECTIONS into relaxed input
+// sections in RELAXED_SECTIONS.  MAP is a prebuilt map from section id
+// indices of INPUT_SECTIONS.
+
+void
+Output_section::convert_input_sections_in_list_to_relaxed_sections(
+  const std::vector<Output_relaxed_input_section*>& relaxed_sections,
+  const Relaxation_map& map,
+  Input_section_list* input_sections)
+{
+  for (size_t i = 0; i < relaxed_sections.size(); ++i)
+    {
+      Output_relaxed_input_section* poris = relaxed_sections[i];
+      Section_id sid(poris->relobj(), poris->shndx());
+      Relaxation_map::const_iterator p = map.find(sid);
+      gold_assert(p != map.end());
+      gold_assert((*input_sections)[p->second].is_input_section());
+      (*input_sections)[p->second] = Input_section(poris);
+    }
+}
+  
+// Convert regular input sections into relaxed input sections. RELAXED_SECTIONS
+// is a vector of pointers to Output_relaxed_input_section or its derived
+// classes.  The relaxed sections must correspond to existing input sections.
+
+void
+Output_section::convert_input_sections_to_relaxed_sections(
+  const std::vector<Output_relaxed_input_section*>& relaxed_sections)
+{
+  gold_assert(parameters->target().may_relax());
+
+  // We want to make sure that restore_states does not undo the effect of
+  // this.  If there is no checkpoint active, just search the current
+  // input section list and replace the sections there.  If there is
+  // a checkpoint, also replace the sections there.
+  
+  // By default, we look at the whole list.
+  size_t limit = this->input_sections_.size();
+
+  if (this->checkpoint_ != NULL)
+    {
+      // Replace input sections with relaxed input section in the saved
+      // copy of the input section list.
+      if (this->checkpoint_->input_sections_saved())
+       {
+         Relaxation_map map;
+         this->build_relaxation_map(
+                   *(this->checkpoint_->input_sections()),
+                   this->checkpoint_->input_sections()->size(),
+                   &map);
+         this->convert_input_sections_in_list_to_relaxed_sections(
+                   relaxed_sections,
+                   map,
+                   this->checkpoint_->input_sections());
+       }
+      else
+       {
+         // We have not copied the input section list yet.  Instead, just
+         // look at the portion that would be saved.
+         limit = this->checkpoint_->input_sections_size();
+       }
+    }
+
+  // Convert input sections in input_section_list.
+  Relaxation_map map;
+  this->build_relaxation_map(this->input_sections_, limit, &map);
+  this->convert_input_sections_in_list_to_relaxed_sections(
+           relaxed_sections,
+           map,
+           &this->input_sections_);
+
+  // Update fast look-up map.
+  if (this->lookup_maps_->is_valid())
+    for (size_t i = 0; i < relaxed_sections.size(); ++i)
       {
-        p->add_input_section(object, shndx);
-        return true;
+       Output_relaxed_input_section* poris = relaxed_sections[i];
+       this->lookup_maps_->add_relaxed_input_section(poris->relobj(),
+                                                     poris->shndx(), poris);
       }
+}
+
+// Update the output section flags based on input section flags.
 
-  // We handle the actual constant merging in Output_merge_data or
-  // Output_merge_string_data.
-  Output_section_data* posd;
-  if (!is_string)
-    posd = new Output_merge_data(entsize, addralign);
+void
+Output_section::update_flags_for_input_section(elfcpp::Elf_Xword flags)
+{
+  // If we created the section with SHF_ALLOC clear, we set the
+  // address.  If we are now setting the SHF_ALLOC flag, we need to
+  // undo that.
+  if ((this->flags_ & elfcpp::SHF_ALLOC) == 0
+      && (flags & elfcpp::SHF_ALLOC) != 0)
+    this->mark_address_invalid();
+
+  this->flags_ |= (flags
+                  & (elfcpp::SHF_WRITE
+                     | elfcpp::SHF_ALLOC
+                     | elfcpp::SHF_EXECINSTR));
+
+  if ((flags & elfcpp::SHF_MERGE) == 0)
+    this->flags_ &=~ elfcpp::SHF_MERGE;
+  else
+    {
+      if (this->current_data_size_for_child() == 0)
+       this->flags_ |= elfcpp::SHF_MERGE;
+    }
+
+  if ((flags & elfcpp::SHF_STRINGS) == 0)
+    this->flags_ &=~ elfcpp::SHF_STRINGS;
   else
     {
-      switch (entsize)
+      if (this->current_data_size_for_child() == 0)
+       this->flags_ |= elfcpp::SHF_STRINGS;
+    }
+}
+
+// Find the merge section into which an input section with index SHNDX in
+// OBJECT has been added.  Return NULL if none found.
+
+Output_section_data*
+Output_section::find_merge_section(const Relobj* object,
+                                  unsigned int shndx) const
+{
+  if (!this->lookup_maps_->is_valid())
+    this->build_lookup_maps();
+  return this->lookup_maps_->find_merge_section(object, shndx);
+}
+
+// Build the lookup maps for merge and relaxed sections.  This is needs
+// to be declared as a const methods so that it is callable with a const
+// Output_section pointer.  The method only updates states of the maps.
+
+void
+Output_section::build_lookup_maps() const
+{
+  this->lookup_maps_->clear();
+  for (Input_section_list::const_iterator p = this->input_sections_.begin();
+       p != this->input_sections_.end();
+       ++p)
+    {
+      if (p->is_merge_section())
+       {
+         Output_merge_base* pomb = p->output_merge_base();
+         Merge_section_properties msp(pomb->is_string(), pomb->entsize(),
+                                      pomb->addralign());
+         this->lookup_maps_->add_merge_section(msp, pomb);
+         for (Output_merge_base::Input_sections::const_iterator is =
+                pomb->input_sections_begin();
+              is != pomb->input_sections_end();
+              ++is) 
+           {
+             const Const_section_id& csid = *is;
+           this->lookup_maps_->add_merge_input_section(csid.first,
+                                                       csid.second, pomb);
+           }
+           
+       }
+      else if (p->is_relaxed_input_section())
        {
-        case 1:
-         posd = new Output_merge_string<char>(addralign);
-         break;
-        case 2:
-         posd = new Output_merge_string<uint16_t>(addralign);
-         break;
-        case 4:
-         posd = new Output_merge_string<uint32_t>(addralign);
-         break;
-        default:
-         return false;
+         Output_relaxed_input_section* poris = p->relaxed_input_section();
+         this->lookup_maps_->add_relaxed_input_section(poris->relobj(),
+                                                       poris->shndx(), poris);
        }
     }
+}
 
-  this->add_output_merge_section(posd, is_string, entsize);
-  posd->add_input_section(object, shndx);
+// Find an relaxed input section corresponding to an input section
+// in OBJECT with index SHNDX.
 
-  return true;
+const Output_relaxed_input_section*
+Output_section::find_relaxed_input_section(const Relobj* object,
+                                          unsigned int shndx) const
+{
+  if (!this->lookup_maps_->is_valid())
+    this->build_lookup_maps();
+  return this->lookup_maps_->find_relaxed_input_section(object, shndx);
 }
 
 // Given an address OFFSET relative to the start of input section
@@ -1845,8 +2490,20 @@ Output_section::is_input_address_mapped(const Relobj* object,
                                        unsigned int shndx,
                                        off_t offset) const
 {
-  gold_assert(object->is_section_specially_mapped(shndx));
+  // Look at the Output_section_data_maps first.
+  const Output_section_data* posd = this->find_merge_section(object, shndx);
+  if (posd == NULL)
+    posd = this->find_relaxed_input_section(object, shndx);
 
+  if (posd != NULL)
+    {
+      section_offset_type output_offset;
+      bool found = posd->output_offset(object, shndx, offset, &output_offset);
+      gold_assert(found);   
+      return output_offset != -1;
+    }
+
+  // Fall back to the slow look-up.
   for (Input_section_list::const_iterator p = this->input_sections_.begin();
        p != this->input_sections_.end();
        ++p)
@@ -1871,10 +2528,23 @@ section_offset_type
 Output_section::output_offset(const Relobj* object, unsigned int shndx,
                              section_offset_type offset) const
 {
-  gold_assert(object->is_section_specially_mapped(shndx));
-  // This can only be called meaningfully when layout is complete.
-  gold_assert(Output_data::is_layout_complete());
+  // This can only be called meaningfully when we know the data size
+  // of this.
+  gold_assert(this->is_data_size_valid());
+
+  // Look at the Output_section_data_maps first.
+  const Output_section_data* posd = this->find_merge_section(object, shndx);
+  if (posd == NULL) 
+    posd = this->find_relaxed_input_section(object, shndx);
+  if (posd != NULL)
+    {
+      section_offset_type output_offset;
+      bool found = posd->output_offset(object, shndx, offset, &output_offset);
+      gold_assert(found);   
+      return output_offset;
+    }
 
+  // Fall back to the slow look-up.
   for (Input_section_list::const_iterator p = this->input_sections_.begin();
        p != this->input_sections_.end();
        ++p)
@@ -1893,9 +2563,21 @@ uint64_t
 Output_section::output_address(const Relobj* object, unsigned int shndx,
                               off_t offset) const
 {
-  gold_assert(object->is_section_specially_mapped(shndx));
-
   uint64_t addr = this->address() + this->first_input_offset_;
+
+  // Look at the Output_section_data_maps first.
+  const Output_section_data* posd = this->find_merge_section(object, shndx);
+  if (posd == NULL) 
+    posd = this->find_relaxed_input_section(object, shndx);
+  if (posd != NULL && posd->is_address_valid())
+    {
+      section_offset_type output_offset;
+      bool found = posd->output_offset(object, shndx, offset, &output_offset);
+      gold_assert(found);
+      return posd->address() + output_offset;
+    }
+
+  // Fall back to the slow look-up.
   for (Input_section_list::const_iterator p = this->input_sections_.begin();
        p != this->input_sections_.end();
        ++p)
@@ -1905,7 +2587,7 @@ Output_section::output_address(const Relobj* object, unsigned int shndx,
       if (p->output_offset(object, shndx, offset, &output_offset))
        {
          if (output_offset == -1)
-           return -1U;
+           return -1ULL;
          return addr + output_offset;
        }
       addr += p->data_size();
@@ -1919,15 +2601,17 @@ Output_section::output_address(const Relobj* object, unsigned int shndx,
   gold_unreachable();
 }
 
-// Return the output address of the start of the merged section for
+// Find the output address of the start of the merged section for
 // input section SHNDX in object OBJECT.
 
-uint64_t
-Output_section::starting_output_address(const Relobj* object,
-                                       unsigned int shndx) const
+bool
+Output_section::find_starting_output_address(const Relobj* object,
+                                            unsigned int shndx,
+                                            uint64_t* paddr) const
 {
-  gold_assert(object->is_section_specially_mapped(shndx));
-
+  // FIXME: This becomes a bottle-neck if we have many relaxed sections.
+  // Looking up the merge section map does not always work as we sometimes
+  // find a merge section without its address set.
   uint64_t addr = this->address() + this->first_input_offset_;
   for (Input_section_list::const_iterator p = this->input_sections_.begin();
        p != this->input_sections_.end();
@@ -1940,11 +2624,16 @@ Output_section::starting_output_address(const Relobj* object,
       // Unfortunately we don't know for sure that input offset 0 is
       // mapped at all.
       if (p->is_merge_section_for(object, shndx))
-       return addr;
+       {
+         *paddr = addr;
+         return true;
+       }
 
       addr += p->data_size();
     }
-  gold_unreachable();
+
+  // We couldn't find a merge output section for this input section.
+  return false;
 }
 
 // Set the data size of an Output_section.  This is where we handle
@@ -1959,6 +2648,10 @@ Output_section::set_final_data_size()
       return;
     }
 
+  if (this->must_sort_attached_input_sections()
+      || this->input_section_order_specified())
+    this->sort_attached_input_sections();
+
   uint64_t address = this->address();
   off_t startoff = this->offset();
   off_t off = startoff + this->first_input_offset_;
@@ -1980,11 +2673,33 @@ Output_section::set_final_data_size()
 void
 Output_section::do_reset_address_and_file_offset()
 {
+  // An unallocated section has no address.  Forcing this means that
+  // we don't need special treatment for symbols defined in debug
+  // sections.  We do the same in the constructor.  This does not
+  // apply to NOLOAD sections though.
+  if (((this->flags_ & elfcpp::SHF_ALLOC) == 0) && !this->is_noload_)
+     this->set_address(0);
+
   for (Input_section_list::iterator p = this->input_sections_.begin();
        p != this->input_sections_.end();
        ++p)
     p->reset_address_and_file_offset();
 }
+  
+// Return true if address and file offset have the values after reset.
+
+bool
+Output_section::do_address_and_file_offset_have_reset_values() const
+{
+  if (this->is_offset_valid())
+    return false;
+
+  // An unallocated section has address 0 after its construction or a reset.
+  if ((this->flags_ & elfcpp::SHF_ALLOC) == 0)
+    return this->is_address_valid() && this->address() == 0;
+  else
+    return !this->is_address_valid();
+}
 
 // Set the TLS offset.  Called only for SHT_TLS sections.
 
@@ -1994,6 +2709,321 @@ Output_section::do_set_tls_offset(uint64_t tls_base)
   this->tls_offset_ = this->address() - tls_base;
 }
 
+// In a few cases we need to sort the input sections attached to an
+// output section.  This is used to implement the type of constructor
+// priority ordering implemented by the GNU linker, in which the
+// priority becomes part of the section name and the sections are
+// sorted by name.  We only do this for an output section if we see an
+// attached input section matching ".ctor.*", ".dtor.*",
+// ".init_array.*" or ".fini_array.*".
+
+class Output_section::Input_section_sort_entry
+{
+ public:
+  Input_section_sort_entry()
+    : input_section_(), index_(-1U), section_has_name_(false),
+      section_name_()
+  { }
+
+  Input_section_sort_entry(const Input_section& input_section,
+                          unsigned int index,
+                          bool must_sort_attached_input_sections)
+    : input_section_(input_section), index_(index),
+      section_has_name_(input_section.is_input_section()
+                       || input_section.is_relaxed_input_section())
+  {
+    if (this->section_has_name_
+        && must_sort_attached_input_sections)
+      {
+       // This is only called single-threaded from Layout::finalize,
+       // so it is OK to lock.  Unfortunately we have no way to pass
+       // in a Task token.
+       const Task* dummy_task = reinterpret_cast<const Task*>(-1);
+       Object* obj = (input_section.is_input_section()
+                      ? input_section.relobj()
+                      : input_section.relaxed_input_section()->relobj());
+       Task_lock_obj<Object> tl(dummy_task, obj);
+
+       // This is a slow operation, which should be cached in
+       // Layout::layout if this becomes a speed problem.
+       this->section_name_ = obj->section_name(input_section.shndx());
+      }
+  }
+
+  // Return the Input_section.
+  const Input_section&
+  input_section() const
+  {
+    gold_assert(this->index_ != -1U);
+    return this->input_section_;
+  }
+
+  // The index of this entry in the original list.  This is used to
+  // make the sort stable.
+  unsigned int
+  index() const
+  {
+    gold_assert(this->index_ != -1U);
+    return this->index_;
+  }
+
+  // Whether there is a section name.
+  bool
+  section_has_name() const
+  { return this->section_has_name_; }
+
+  // The section name.
+  const std::string&
+  section_name() const
+  {
+    gold_assert(this->section_has_name_);
+    return this->section_name_;
+  }
+
+  // Return true if the section name has a priority.  This is assumed
+  // to be true if it has a dot after the initial dot.
+  bool
+  has_priority() const
+  {
+    gold_assert(this->section_has_name_);
+    return this->section_name_.find('.', 1) != std::string::npos;
+  }
+
+  // Return true if this an input file whose base name matches
+  // FILE_NAME.  The base name must have an extension of ".o", and
+  // must be exactly FILE_NAME.o or FILE_NAME, one character, ".o".
+  // This is to match crtbegin.o as well as crtbeginS.o without
+  // getting confused by other possibilities.  Overall matching the
+  // file name this way is a dreadful hack, but the GNU linker does it
+  // in order to better support gcc, and we need to be compatible.
+  bool
+  match_file_name(const char* match_file_name) const
+  {
+    const std::string& file_name(this->input_section_.relobj()->name());
+    const char* base_name = lbasename(file_name.c_str());
+    size_t match_len = strlen(match_file_name);
+    if (strncmp(base_name, match_file_name, match_len) != 0)
+      return false;
+    size_t base_len = strlen(base_name);
+    if (base_len != match_len + 2 && base_len != match_len + 3)
+      return false;
+    return memcmp(base_name + base_len - 2, ".o", 2) == 0;
+  }
+
+  // Returns 1 if THIS should appear before S in section order, -1 if S
+  // appears before THIS and 0 if they are not comparable.
+  int
+  compare_section_ordering(const Input_section_sort_entry& s) const
+  {
+    unsigned int this_secn_index = this->input_section_.section_order_index();
+    unsigned int s_secn_index = s.input_section().section_order_index();
+    if (this_secn_index > 0 && s_secn_index > 0)
+      {
+        if (this_secn_index < s_secn_index)
+          return 1;
+        else if (this_secn_index > s_secn_index)
+          return -1;
+      }
+    return 0;
+  }
+
+ private:
+  // The Input_section we are sorting.
+  Input_section input_section_;
+  // The index of this Input_section in the original list.
+  unsigned int index_;
+  // Whether this Input_section has a section name--it won't if this
+  // is some random Output_section_data.
+  bool section_has_name_;
+  // The section name if there is one.
+  std::string section_name_;
+};
+
+// Return true if S1 should come before S2 in the output section.
+
+bool
+Output_section::Input_section_sort_compare::operator()(
+    const Output_section::Input_section_sort_entry& s1,
+    const Output_section::Input_section_sort_entry& s2) const
+{
+  // crtbegin.o must come first.
+  bool s1_begin = s1.match_file_name("crtbegin");
+  bool s2_begin = s2.match_file_name("crtbegin");
+  if (s1_begin || s2_begin)
+    {
+      if (!s1_begin)
+       return false;
+      if (!s2_begin)
+       return true;
+      return s1.index() < s2.index();
+    }
+
+  // crtend.o must come last.
+  bool s1_end = s1.match_file_name("crtend");
+  bool s2_end = s2.match_file_name("crtend");
+  if (s1_end || s2_end)
+    {
+      if (!s1_end)
+       return true;
+      if (!s2_end)
+       return false;
+      return s1.index() < s2.index();
+    }
+
+  // We sort all the sections with no names to the end.
+  if (!s1.section_has_name() || !s2.section_has_name())
+    {
+      if (s1.section_has_name())
+       return true;
+      if (s2.section_has_name())
+       return false;
+      return s1.index() < s2.index();
+    }
+
+  // A section with a priority follows a section without a priority.
+  bool s1_has_priority = s1.has_priority();
+  bool s2_has_priority = s2.has_priority();
+  if (s1_has_priority && !s2_has_priority)
+    return false;
+  if (!s1_has_priority && s2_has_priority)
+    return true;
+
+  // Check if a section order exists for these sections through a section
+  // ordering file.  If sequence_num is 0, an order does not exist.
+  int sequence_num = s1.compare_section_ordering(s2);
+  if (sequence_num != 0)
+    return sequence_num == 1;
+
+  // Otherwise we sort by name.
+  int compare = s1.section_name().compare(s2.section_name());
+  if (compare != 0)
+    return compare < 0;
+
+  // Otherwise we keep the input order.
+  return s1.index() < s2.index();
+}
+
+// Return true if S1 should come before S2 in an .init_array or .fini_array
+// output section.
+
+bool
+Output_section::Input_section_sort_init_fini_compare::operator()(
+    const Output_section::Input_section_sort_entry& s1,
+    const Output_section::Input_section_sort_entry& s2) const
+{
+  // We sort all the sections with no names to the end.
+  if (!s1.section_has_name() || !s2.section_has_name())
+    {
+      if (s1.section_has_name())
+       return true;
+      if (s2.section_has_name())
+       return false;
+      return s1.index() < s2.index();
+    }
+
+  // A section without a priority follows a section with a priority.
+  // This is the reverse of .ctors and .dtors sections.
+  bool s1_has_priority = s1.has_priority();
+  bool s2_has_priority = s2.has_priority();
+  if (s1_has_priority && !s2_has_priority)
+    return true;
+  if (!s1_has_priority && s2_has_priority)
+    return false;
+
+  // Check if a section order exists for these sections through a section
+  // ordering file.  If sequence_num is 0, an order does not exist.
+  int sequence_num = s1.compare_section_ordering(s2);
+  if (sequence_num != 0)
+    return sequence_num == 1;
+
+  // Otherwise we sort by name.
+  int compare = s1.section_name().compare(s2.section_name());
+  if (compare != 0)
+    return compare < 0;
+
+  // Otherwise we keep the input order.
+  return s1.index() < s2.index();
+}
+
+// Return true if S1 should come before S2.  Sections that do not match
+// any pattern in the section ordering file are placed ahead of the sections
+// that match some pattern.
+
+bool
+Output_section::Input_section_sort_section_order_index_compare::operator()(
+    const Output_section::Input_section_sort_entry& s1,
+    const Output_section::Input_section_sort_entry& s2) const
+{
+  unsigned int s1_secn_index = s1.input_section().section_order_index();
+  unsigned int s2_secn_index = s2.input_section().section_order_index();
+
+  // Keep input order if section ordering cannot determine order.
+  if (s1_secn_index == s2_secn_index)
+    return s1.index() < s2.index();
+  
+  return s1_secn_index < s2_secn_index;
+}
+
+// Sort the input sections attached to an output section.
+
+void
+Output_section::sort_attached_input_sections()
+{
+  if (this->attached_input_sections_are_sorted_)
+    return;
+
+  if (this->checkpoint_ != NULL
+      && !this->checkpoint_->input_sections_saved())
+    this->checkpoint_->save_input_sections();
+
+  // The only thing we know about an input section is the object and
+  // the section index.  We need the section name.  Recomputing this
+  // is slow but this is an unusual case.  If this becomes a speed
+  // problem we can cache the names as required in Layout::layout.
+
+  // We start by building a larger vector holding a copy of each
+  // Input_section, plus its current index in the list and its name.
+  std::vector<Input_section_sort_entry> sort_list;
+
+  unsigned int i = 0;
+  for (Input_section_list::iterator p = this->input_sections_.begin();
+       p != this->input_sections_.end();
+       ++p, ++i)
+      sort_list.push_back(Input_section_sort_entry(*p, i,
+                            this->must_sort_attached_input_sections()));
+
+  // Sort the input sections.
+  if (this->must_sort_attached_input_sections())
+    {
+      if (this->type() == elfcpp::SHT_PREINIT_ARRAY
+          || this->type() == elfcpp::SHT_INIT_ARRAY
+          || this->type() == elfcpp::SHT_FINI_ARRAY)
+        std::sort(sort_list.begin(), sort_list.end(),
+                 Input_section_sort_init_fini_compare());
+      else
+        std::sort(sort_list.begin(), sort_list.end(),
+                 Input_section_sort_compare());
+    }
+  else
+    {
+      gold_assert(parameters->options().section_ordering_file());
+      std::sort(sort_list.begin(), sort_list.end(),
+               Input_section_sort_section_order_index_compare());
+    }
+
+  // Copy the sorted input sections back to our list.
+  this->input_sections_.clear();
+  for (std::vector<Input_section_sort_entry>::iterator p = sort_list.begin();
+       p != sort_list.end();
+       ++p)
+    this->input_sections_.push_back(p->input_section());
+  sort_list.clear();
+
+  // Remember that we sorted the input sections, since we might get
+  // called again.
+  this->attached_input_sections_are_sorted_ = true;
+}
+
 // Write the section header to *OSHDR.
 
 template<int size, bool big_endian>
@@ -2049,20 +3079,35 @@ Output_section::do_write(Output_file* of)
 {
   gold_assert(!this->requires_postprocessing());
 
+  // If the target performs relaxation, we delay filler generation until now.
+  gold_assert(!this->generate_code_fills_at_write_ || this->fills_.empty());
+
   off_t output_section_file_offset = this->offset();
   for (Fill_list::iterator p = this->fills_.begin();
        p != this->fills_.end();
        ++p)
     {
-      std::string fill_data(parameters->target()->code_fill(p->length()));
+      std::string fill_data(parameters->target().code_fill(p->length()));
       of->write(output_section_file_offset + p->section_offset(),
                fill_data.data(), fill_data.size());
     }
 
+  off_t off = this->offset() + this->first_input_offset_;
   for (Input_section_list::iterator p = this->input_sections_.begin();
        p != this->input_sections_.end();
        ++p)
-    p->write(of);
+    {
+      off_t aligned_off = align_address(off, p->addralign());
+      if (this->generate_code_fills_at_write_ && (off != aligned_off))
+       {
+         size_t fill_len = aligned_off - off;
+         std::string fill_data(parameters->target().code_fill(fill_len));
+         of->write(off, fill_data.data(), fill_data.size());
+       }
+
+      p->write(of);
+      off = aligned_off + p->data_size();
+    }
 }
 
 // If a section requires postprocessing, create the buffer to use.
@@ -2103,13 +3148,15 @@ Output_section::write_to_postprocessing_buffer()
 {
   gold_assert(this->requires_postprocessing());
 
-  Target* target = parameters->target();
+  // If the target performs relaxation, we delay filler generation until now.
+  gold_assert(!this->generate_code_fills_at_write_ || this->fills_.empty());
+
   unsigned char* buffer = this->postprocessing_buffer();
   for (Fill_list::iterator p = this->fills_.begin();
        p != this->fills_.end();
        ++p)
     {
-      std::string fill_data(target->code_fill(p->length()));
+      std::string fill_data(parameters->target().code_fill(p->length()));
       memcpy(buffer + p->section_offset(), fill_data.data(),
             fill_data.size());
     }
@@ -2119,9 +3166,16 @@ Output_section::write_to_postprocessing_buffer()
        p != this->input_sections_.end();
        ++p)
     {
-      off = align_address(off, p->addralign());
-      p->write_to_buffer(buffer + off);
-      off += p->data_size();
+      off_t aligned_off = align_address(off, p->addralign());
+      if (this->generate_code_fills_at_write_ && (off != aligned_off))
+       {
+         size_t fill_len = aligned_off - off;
+         std::string fill_data(parameters->target().code_fill(fill_len));
+         memcpy(buffer + off, fill_data.data(), fill_data.size());
+       }
+
+      p->write_to_buffer(buffer + aligned_off);
+      off = aligned_off + p->data_size();
     }
 }
 
@@ -2139,8 +3193,15 @@ uint64_t
 Output_section::get_input_sections(
     uint64_t address,
     const std::string& fill,
-    std::list<std::pair<Relobj*, unsigned int> >* input_sections)
+    std::list<Input_section>* input_sections)
 {
+  if (this->checkpoint_ != NULL
+      && !this->checkpoint_->input_sections_saved())
+    this->checkpoint_->save_input_sections();
+
+  // Invalidate fast look-up maps.
+  this->lookup_maps_->invalidate();
+
   uint64_t orig_address = address;
 
   address = align_address(address, this->addralign());
@@ -2150,8 +3211,10 @@ Output_section::get_input_sections(
        p != this->input_sections_.end();
        ++p)
     {
-      if (p->is_input_section())
-       input_sections->push_back(std::make_pair(p->relobj(), p->shndx()));
+      if (p->is_input_section()
+         || p->is_relaxed_input_section()
+         || p->is_merge_section())
+       input_sections->push_back(*p);
       else
        {
          uint64_t aligned_address = align_address(address, p->addralign());
@@ -2186,14 +3249,16 @@ Output_section::get_input_sections(
   return data_size;
 }
 
-// Add an input section from a script.
+// Add a script input section.  SIS is an Output_section::Input_section,
+// which can be either a plain input section or a special input section like
+// a relaxed input section.  For a special input section, its size must be
+// finalized.
 
 void
-Output_section::add_input_section_for_script(Relobj* object,
-                                            unsigned int shndx,
-                                            off_t data_size,
-                                            uint64_t addralign)
+Output_section::add_script_input_section(const Input_section& sis)
 {
+  uint64_t data_size = sis.data_size();
+  uint64_t addralign = sis.addralign();
   if (addralign > this->addralign_)
     this->addralign_ = addralign;
 
@@ -2204,8 +3269,129 @@ Output_section::add_input_section_for_script(Relobj* object,
   this->set_current_data_size_for_child(aligned_offset_in_section
                                        + data_size);
 
-  this->input_sections_.push_back(Input_section(object, shndx,
-                                               data_size, addralign));
+  this->input_sections_.push_back(sis);
+
+  // Update fast lookup maps if necessary. 
+  if (this->lookup_maps_->is_valid())
+    {
+      if (sis.is_merge_section())
+       {
+         Output_merge_base* pomb = sis.output_merge_base();
+         Merge_section_properties msp(pomb->is_string(), pomb->entsize(),
+                                      pomb->addralign());
+         this->lookup_maps_->add_merge_section(msp, pomb);
+         for (Output_merge_base::Input_sections::const_iterator p =
+                pomb->input_sections_begin();
+              p != pomb->input_sections_end();
+              ++p)
+           this->lookup_maps_->add_merge_input_section(p->first, p->second,
+                                                       pomb);
+       }
+      else if (sis.is_relaxed_input_section())
+       {
+         Output_relaxed_input_section* poris = sis.relaxed_input_section();
+         this->lookup_maps_->add_relaxed_input_section(poris->relobj(),
+                                                       poris->shndx(), poris);
+       }
+    }
+}
+
+// Save states for relaxation.
+
+void
+Output_section::save_states()
+{
+  gold_assert(this->checkpoint_ == NULL);
+  Checkpoint_output_section* checkpoint =
+    new Checkpoint_output_section(this->addralign_, this->flags_,
+                                 this->input_sections_,
+                                 this->first_input_offset_,
+                                 this->attached_input_sections_are_sorted_);
+  this->checkpoint_ = checkpoint;
+  gold_assert(this->fills_.empty());
+}
+
+void
+Output_section::discard_states()
+{
+  gold_assert(this->checkpoint_ != NULL);
+  delete this->checkpoint_;
+  this->checkpoint_ = NULL;
+  gold_assert(this->fills_.empty());
+
+  // Simply invalidate the fast lookup maps since we do not keep
+  // track of them.
+  this->lookup_maps_->invalidate();
+}
+
+void
+Output_section::restore_states()
+{
+  gold_assert(this->checkpoint_ != NULL);
+  Checkpoint_output_section* checkpoint = this->checkpoint_;
+
+  this->addralign_ = checkpoint->addralign();
+  this->flags_ = checkpoint->flags();
+  this->first_input_offset_ = checkpoint->first_input_offset();
+
+  if (!checkpoint->input_sections_saved())
+    {
+      // If we have not copied the input sections, just resize it.
+      size_t old_size = checkpoint->input_sections_size();
+      gold_assert(this->input_sections_.size() >= old_size);
+      this->input_sections_.resize(old_size);
+    }
+  else
+    {
+      // We need to copy the whole list.  This is not efficient for
+      // extremely large output with hundreads of thousands of input
+      // objects.  We may need to re-think how we should pass sections
+      // to scripts.
+      this->input_sections_ = *checkpoint->input_sections();
+    }
+
+  this->attached_input_sections_are_sorted_ =
+    checkpoint->attached_input_sections_are_sorted();
+
+  // Simply invalidate the fast lookup maps since we do not keep
+  // track of them.
+  this->lookup_maps_->invalidate();
+}
+
+// Update the section offsets of input sections in this.  This is required if
+// relaxation causes some input sections to change sizes.
+
+void
+Output_section::adjust_section_offsets()
+{
+  if (!this->section_offsets_need_adjustment_)
+    return;
+
+  off_t off = 0;
+  for (Input_section_list::iterator p = this->input_sections_.begin();
+       p != this->input_sections_.end();
+       ++p)
+    {
+      off = align_address(off, p->addralign());
+      if (p->is_input_section())
+       p->relobj()->set_section_offset(p->shndx(), off);
+      off += p->data_size();
+    }
+
+  this->section_offsets_need_adjustment_ = false;
+}
+
+// Print to the map file.
+
+void
+Output_section::do_print_to_mapfile(Mapfile* mapfile) const
+{
+  mapfile->print_output_section(this);
+
+  for (Input_section_list::const_iterator p = this->input_sections_.begin();
+       p != this->input_sections_.end();
+       ++p)
+    p->print_to_mapfile(mapfile);
 }
 
 // Print stats for merge sections to stderr.
@@ -2235,8 +3421,13 @@ Output_segment::Output_segment(elfcpp::Elf_Word type, elfcpp::Elf_Word flags)
     type_(type),
     flags_(flags),
     is_max_align_known_(false),
-    are_addresses_set_(false)
+    are_addresses_set_(false),
+    is_large_data_segment_(false)
 {
+  // The ELF ABI specifies that a PT_TLS segment always has PF_R as
+  // the flags.
+  if (type == elfcpp::PT_TLS)
+    this->flags_ = elfcpp::PF_R;
 }
 
 // Add an Output_section to an Output_segment.
@@ -2244,13 +3435,14 @@ Output_segment::Output_segment(elfcpp::Elf_Word type, elfcpp::Elf_Word flags)
 void
 Output_segment::add_output_section(Output_section* os,
                                   elfcpp::Elf_Word seg_flags,
-                                  bool front)
+                                  bool do_sort)
 {
   gold_assert((os->flags() & elfcpp::SHF_ALLOC) != 0);
   gold_assert(!this->is_max_align_known_);
+  gold_assert(os->is_large_data_section() == this->is_large_data_segment());
+  gold_assert(this->type() == elfcpp::PT_LOAD || !do_sort);
 
-  // Update the segment flags.
-  this->flags_ |= seg_flags;
+  this->update_flags_for_output_section(seg_flags);
 
   Output_segment::Output_data_list* pdl;
   if (os->type() == elfcpp::SHT_NOBITS)
@@ -2258,19 +3450,12 @@ Output_segment::add_output_section(Output_section* os,
   else
     pdl = &this->output_data_;
 
-  // So that PT_NOTE segments will work correctly, we need to ensure
-  // that all SHT_NOTE sections are adjacent.  This will normally
-  // happen automatically, because all the SHT_NOTE input sections
-  // will wind up in the same output section.  However, it is possible
-  // for multiple SHT_NOTE input sections to have different section
-  // flags, and thus be in different output sections, but for the
-  // different section flags to map into the same segment flags and
-  // thus the same output segment.
-
   // Note that while there may be many input sections in an output
   // section, there are normally only a few output sections in an
-  // output segment.  This loop is expected to be fast.
+  // output segment.  The loops below are expected to be fast.
 
+  // So that PT_NOTE segments will work correctly, we need to ensure
+  // that all SHT_NOTE sections are adjacent.
   if (os->type() == elfcpp::SHT_NOTE && !pdl->empty())
     {
       Output_segment::Output_data_list::iterator p = pdl->end();
@@ -2279,7 +3464,6 @@ Output_segment::add_output_section(Output_section* os,
          --p;
          if ((*p)->is_section_type(elfcpp::SHT_NOTE))
            {
-             // We don't worry about the FRONT parameter.
              ++p;
              pdl->insert(p, os);
              return;
@@ -2293,57 +3477,251 @@ Output_segment::add_output_section(Output_section* os,
   // case: we group the SHF_TLS/SHT_NOBITS sections right after the
   // SHF_TLS/SHT_PROGBITS sections.  This lets us set up PT_TLS
   // correctly.  SHF_TLS sections get added to both a PT_LOAD segment
-  // and the PT_TLS segment -- we do this grouping only for the
-  // PT_LOAD segment.
+  // and the PT_TLS segment; we do this grouping only for the PT_LOAD
+  // segment.
   if (this->type_ != elfcpp::PT_TLS
-      && (os->flags() & elfcpp::SHF_TLS) != 0
-      && !this->output_data_.empty())
+      && (os->flags() & elfcpp::SHF_TLS) != 0)
     {
       pdl = &this->output_data_;
-      bool nobits = os->type() == elfcpp::SHT_NOBITS;
-      bool sawtls = false;
-      Output_segment::Output_data_list::iterator p = pdl->end();
-      do
+      if (!pdl->empty())
        {
-         --p;
-         bool insert;
-         if ((*p)->is_section_flag_set(elfcpp::SHF_TLS))
+         bool nobits = os->type() == elfcpp::SHT_NOBITS;
+         bool sawtls = false;
+         Output_segment::Output_data_list::iterator p = pdl->end();
+         gold_assert(p != pdl->begin());
+         do
            {
-             sawtls = true;
-             // Put a NOBITS section after the first TLS section.
-             // But a PROGBITS section after the first TLS/PROGBITS
-             // section.
-             insert = nobits || !(*p)->is_section_type(elfcpp::SHT_NOBITS);
+             --p;
+             bool insert;
+             if ((*p)->is_section_flag_set(elfcpp::SHF_TLS))
+               {
+                 sawtls = true;
+                 // Put a NOBITS section after the first TLS section.
+                 // Put a PROGBITS section after the first
+                 // TLS/PROGBITS section.
+                 insert = nobits || !(*p)->is_section_type(elfcpp::SHT_NOBITS);
+               }
+             else
+               {
+                 // If we've gone past the TLS sections, but we've
+                 // seen a TLS section, then we need to insert this
+                 // section now.
+                 insert = sawtls;
+               }
+
+             if (insert)
+               {
+                 ++p;
+                 pdl->insert(p, os);
+                 return;
+               }
            }
-         else
+         while (p != pdl->begin());
+       }
+
+      // There are no TLS sections yet; put this one at the requested
+      // location in the section list.
+    }
+
+  if (do_sort)
+    {
+      // For the PT_GNU_RELRO segment, we need to group relro
+      // sections, and we need to put them before any non-relro
+      // sections.  Any relro local sections go before relro non-local
+      // sections.  One section may be marked as the last relro
+      // section.
+      if (os->is_relro())
+       {
+         gold_assert(pdl == &this->output_data_);
+         Output_segment::Output_data_list::iterator p;
+         for (p = pdl->begin(); p != pdl->end(); ++p)
            {
-             // If we've gone past the TLS sections, but we've seen a
-             // TLS section, then we need to insert this section now.
-             insert = sawtls;
+             if (!(*p)->is_section())
+               break;
+
+             Output_section* pos = (*p)->output_section();
+             if (!pos->is_relro()
+                 || (os->is_relro_local() && !pos->is_relro_local())
+                 || (!os->is_last_relro() && pos->is_last_relro()))
+               break;
            }
 
-         if (insert)
+         pdl->insert(p, os);
+         return;
+       }
+
+      // One section may be marked as the first section which follows
+      // the relro sections.
+      if (os->is_first_non_relro())
+       {
+         gold_assert(pdl == &this->output_data_);
+         Output_segment::Output_data_list::iterator p;
+         for (p = pdl->begin(); p != pdl->end(); ++p)
+           {
+             if (!(*p)->is_section())
+               break;
+
+             Output_section* pos = (*p)->output_section();
+             if (!pos->is_relro())
+               break;
+           }
+
+         pdl->insert(p, os);
+         return;
+       }
+    }
+
+  // Small data sections go at the end of the list of data sections.
+  // If OS is not small, and there are small sections, we have to
+  // insert it before the first small section.
+  if (os->type() != elfcpp::SHT_NOBITS
+      && !os->is_small_section()
+      && !pdl->empty()
+      && pdl->back()->is_section()
+      && pdl->back()->output_section()->is_small_section())
+    {
+      for (Output_segment::Output_data_list::iterator p = pdl->begin();
+          p != pdl->end();
+          ++p)
+       {
+         if ((*p)->is_section()
+             && (*p)->output_section()->is_small_section())
            {
-             // We don't worry about the FRONT parameter.
-             ++p;
              pdl->insert(p, os);
              return;
            }
        }
-      while (p != pdl->begin());
+      gold_unreachable();
+    }
 
-      // There are no TLS sections yet; put this one at the requested
-      // location in the section list.
+  // A small BSS section goes at the start of the BSS sections, after
+  // other small BSS sections.
+  if (os->type() == elfcpp::SHT_NOBITS && os->is_small_section())
+    {
+      for (Output_segment::Output_data_list::iterator p = pdl->begin();
+          p != pdl->end();
+          ++p)
+       {
+         if (!(*p)->is_section()
+             || !(*p)->output_section()->is_small_section())
+           {
+             pdl->insert(p, os);
+             return;
+           }
+       }
     }
 
-  if (front)
-    pdl->push_front(os);
-  else
-    pdl->push_back(os);
+  // A large BSS section goes at the end of the BSS sections, which
+  // means that one that is not large must come before the first large
+  // one.
+  if (os->type() == elfcpp::SHT_NOBITS
+      && !os->is_large_section()
+      && !pdl->empty()
+      && pdl->back()->is_section()
+      && pdl->back()->output_section()->is_large_section())
+    {
+      for (Output_segment::Output_data_list::iterator p = pdl->begin();
+          p != pdl->end();
+          ++p)
+       {
+         if ((*p)->is_section()
+             && (*p)->output_section()->is_large_section())
+           {
+             pdl->insert(p, os);
+             return;
+           }
+       }
+      gold_unreachable();
+    }
+
+  // We do some further output section sorting in order to make the
+  // generated program run more efficiently.  We should only do this
+  // when not using a linker script, so it is controled by the DO_SORT
+  // parameter.
+  if (do_sort)
+    {
+      // FreeBSD requires the .interp section to be in the first page
+      // of the executable.  That is a more efficient location anyhow
+      // for any OS, since it means that the kernel will have the data
+      // handy after it reads the program headers.
+      if (os->is_interp() && !pdl->empty())
+       {
+         pdl->insert(pdl->begin(), os);
+         return;
+       }
+
+      // Put loadable non-writable notes immediately after the .interp
+      // sections, so that the PT_NOTE segment is on the first page of
+      // the executable.
+      if (os->type() == elfcpp::SHT_NOTE
+         && (os->flags() & elfcpp::SHF_WRITE) == 0
+         && !pdl->empty())
+       {
+         Output_segment::Output_data_list::iterator p = pdl->begin();
+         if ((*p)->is_section() && (*p)->output_section()->is_interp())
+           ++p;
+         pdl->insert(p, os);
+         return;
+       }
+
+      // If this section is used by the dynamic linker, and it is not
+      // writable, then put it first, after the .interp section and
+      // any loadable notes.  This makes it more likely that the
+      // dynamic linker will have to read less data from the disk.
+      if (os->is_dynamic_linker_section()
+         && !pdl->empty()
+         && (os->flags() & elfcpp::SHF_WRITE) == 0)
+       {
+         bool is_reloc = (os->type() == elfcpp::SHT_REL
+                          || os->type() == elfcpp::SHT_RELA);
+         Output_segment::Output_data_list::iterator p = pdl->begin();
+         while (p != pdl->end()
+                && (*p)->is_section()
+                && ((*p)->output_section()->is_dynamic_linker_section()
+                    || (*p)->output_section()->type() == elfcpp::SHT_NOTE))
+           {
+             // Put reloc sections after the other ones.  Putting the
+             // dynamic reloc sections first confuses BFD, notably
+             // objcopy and strip.
+             if (!is_reloc
+                 && ((*p)->output_section()->type() == elfcpp::SHT_REL
+                     || (*p)->output_section()->type() == elfcpp::SHT_RELA))
+               break;
+             ++p;
+           }
+         pdl->insert(p, os);
+         return;
+       }
+    }
+
+  // If there were no constraints on the output section, just add it
+  // to the end of the list.
+  pdl->push_back(os);
+}
+
+// Remove an Output_section from this segment.  It is an error if it
+// is not present.
+
+void
+Output_segment::remove_output_section(Output_section* os)
+{
+  // We only need this for SHT_PROGBITS.
+  gold_assert(os->type() == elfcpp::SHT_PROGBITS);
+  for (Output_data_list::iterator p = this->output_data_.begin();
+       p != this->output_data_.end();
+       ++p)
+   {
+     if (*p == os)
+       {
+         this->output_data_.erase(p);
+         return;
+       }
+   }
+  gold_unreachable();
 }
 
-// Add an Output_data (which is not an Output_section) to the start of
-// a segment.
+// Add an Output_data (which need not be an Output_section) to the
+// start of a segment.
 
 void
 Output_segment::add_initial_output_data(Output_data* od)
@@ -2352,6 +3730,16 @@ Output_segment::add_initial_output_data(Output_data* od)
   this->output_data_.push_front(od);
 }
 
+// Return whether the first data section is a relro section.
+
+bool
+Output_segment::is_first_section_relro() const
+{
+  return (!this->output_data_.empty()
+         && this->output_data_.front()->is_section()
+         && this->output_data_.front()->output_section()->is_relro());
+}
+
 // Return the maximum alignment of the Output_data in Output_segment.
 
 uint64_t
@@ -2421,11 +3809,58 @@ Output_segment::dynamic_reloc_count_list(const Output_data_list* pdl) const
 // *POFF and *PSHNDX.
 
 uint64_t
-Output_segment::set_section_addresses(bool reset, uint64_t addr, off_t* poff,
+Output_segment::set_section_addresses(const Layout* layout, bool reset,
+                                      uint64_t addr,
+                                     unsigned int increase_relro,
+                                     off_t* poff,
                                      unsigned int* pshndx)
 {
   gold_assert(this->type_ == elfcpp::PT_LOAD);
 
+  off_t orig_off = *poff;
+
+  // If we have relro sections, we need to pad forward now so that the
+  // relro sections plus INCREASE_RELRO end on a common page boundary.
+  if (parameters->options().relro()
+      && this->is_first_section_relro()
+      && (!this->are_addresses_set_ || reset))
+    {
+      uint64_t relro_size = 0;
+      off_t off = *poff;
+      for (Output_data_list::iterator p = this->output_data_.begin();
+          p != this->output_data_.end();
+          ++p)
+       {
+         if (!(*p)->is_section())
+           break;
+         Output_section* pos = (*p)->output_section();
+         if (!pos->is_relro())
+           break;
+         gold_assert(!(*p)->is_section_flag_set(elfcpp::SHF_TLS));
+         if ((*p)->is_address_valid())
+           relro_size += (*p)->data_size();
+         else
+           {
+             // FIXME: This could be faster.
+             (*p)->set_address_and_file_offset(addr + relro_size,
+                                               off + relro_size);
+             relro_size += (*p)->data_size();
+             (*p)->reset_address_and_file_offset();
+           }
+       }
+      relro_size += increase_relro;
+
+      uint64_t page_align = parameters->target().common_pagesize();
+
+      // Align to offset N such that (N + RELRO_SIZE) % PAGE_ALIGN == 0.
+      uint64_t desired_align = page_align - (relro_size % page_align);
+      if (desired_align < *poff % page_align)
+       *poff += page_align - *poff % page_align;
+      *poff += desired_align - *poff % page_align;
+      addr += *poff - orig_off;
+      orig_off = *poff;
+    }
+
   if (!reset && this->are_addresses_set_)
     {
       gold_assert(this->paddr_ == addr);
@@ -2438,17 +3873,30 @@ Output_segment::set_section_addresses(bool reset, uint64_t addr, off_t* poff,
       this->are_addresses_set_ = true;
     }
 
-  off_t orig_off = *poff;
+  bool in_tls = false;
+
   this->offset_ = orig_off;
 
-  addr = this->set_section_list_addresses(reset, &this->output_data_,
-                                         addr, poff, pshndx);
+  addr = this->set_section_list_addresses(layout, reset, &this->output_data_,
+                                         addr, poff, pshndx, &in_tls);
   this->filesz_ = *poff - orig_off;
 
   off_t off = *poff;
 
-  uint64_t ret = this->set_section_list_addresses(reset, &this->output_bss_,
-                                                 addr, poff, pshndx);
+  uint64_t ret = this->set_section_list_addresses(layout, reset,
+                                                  &this->output_bss_,
+                                                 addr, poff, pshndx,
+                                                  &in_tls);
+
+  // If the last section was a TLS section, align upward to the
+  // alignment of the TLS segment, so that the overall size of the TLS
+  // segment is aligned.
+  if (in_tls)
+    {
+      uint64_t segment_align = layout->tls_segment()->maximum_alignment();
+      *poff = align_address(*poff, segment_align);
+    }
+
   this->memsz_ = *poff - orig_off;
 
   // Ignore the file offset adjustments made by the BSS Output_data
@@ -2462,9 +3910,11 @@ Output_segment::set_section_addresses(bool reset, uint64_t addr, off_t* poff,
 // structures.
 
 uint64_t
-Output_segment::set_section_list_addresses(bool reset, Output_data_list* pdl,
+Output_segment::set_section_list_addresses(const Layout* layout, bool reset,
+                                           Output_data_list* pdl,
                                           uint64_t addr, off_t* poff,
-                                          unsigned int* pshndx)
+                                          unsigned int* pshndx,
+                                           bool* in_tls)
 {
   off_t startoff = *poff;
 
@@ -2480,24 +3930,81 @@ Output_segment::set_section_list_addresses(bool reset, Output_data_list* pdl,
       // already have an address.
       if (!(*p)->is_address_valid())
        {
-         off = align_address(off, (*p)->addralign());
+          uint64_t align = (*p)->addralign();
+
+          if ((*p)->is_section_flag_set(elfcpp::SHF_TLS))
+            {
+              // Give the first TLS section the alignment of the
+              // entire TLS segment.  Otherwise the TLS segment as a
+              // whole may be misaligned.
+              if (!*in_tls)
+                {
+                  Output_segment* tls_segment = layout->tls_segment();
+                  gold_assert(tls_segment != NULL);
+                  uint64_t segment_align = tls_segment->maximum_alignment();
+                  gold_assert(segment_align >= align);
+                  align = segment_align;
+
+                  *in_tls = true;
+                }
+            }
+          else
+            {
+              // If this is the first section after the TLS segment,
+              // align it to at least the alignment of the TLS
+              // segment, so that the size of the overall TLS segment
+              // is aligned.
+              if (*in_tls)
+                {
+                  uint64_t segment_align =
+                      layout->tls_segment()->maximum_alignment();
+                  if (segment_align > align)
+                    align = segment_align;
+
+                  *in_tls = false;
+                }
+            }
+
+         off = align_address(off, align);
          (*p)->set_address_and_file_offset(addr + (off - startoff), off);
        }
       else
        {
          // The script may have inserted a skip forward, but it
          // better not have moved backward.
-         gold_assert((*p)->address() >= addr + (off - startoff));
-         off += (*p)->address() - (addr + (off - startoff));
+         if ((*p)->address() >= addr + (off - startoff))
+           off += (*p)->address() - (addr + (off - startoff));
+         else
+           {
+             if (!layout->script_options()->saw_sections_clause())
+               gold_unreachable();
+             else
+               {
+                 Output_section* os = (*p)->output_section();
+
+                 // Cast to unsigned long long to avoid format warnings.
+                 unsigned long long previous_dot =
+                   static_cast<unsigned long long>(addr + (off - startoff));
+                 unsigned long long dot =
+                   static_cast<unsigned long long>((*p)->address());
+
+                 if (os == NULL)
+                   gold_error(_("dot moves backward in linker script "
+                                "from 0x%llx to 0x%llx"), previous_dot, dot);
+                 else
+                   gold_error(_("address of section '%s' moves backward "
+                                "from 0x%llx to 0x%llx"),
+                              os->name(), previous_dot, dot);
+               }
+           }
          (*p)->set_file_offset(off);
          (*p)->finalize_data_size();
        }
 
-      // Unless this is a PT_TLS segment, we want to ignore the size
-      // of a SHF_TLS/SHT_NOBITS section.  Such a section does not
-      // affect the size of a PT_LOAD segment.
-      if (this->type_ == elfcpp::PT_TLS
-         || !(*p)->is_section_flag_set(elfcpp::SHF_TLS)
+      // We want to ignore the size of a SHF_TLS or SHT_NOBITS
+      // section.  Such a section does not affect the size of a
+      // PT_LOAD segment.
+      if (!(*p)->is_section_flag_set(elfcpp::SHF_TLS)
          || !(*p)->is_section_type(elfcpp::SHT_NOBITS))
        off += (*p)->data_size();
 
@@ -2513,10 +4020,10 @@ Output_segment::set_section_list_addresses(bool reset, Output_data_list* pdl,
 }
 
 // For a non-PT_LOAD segment, set the offset from the sections, if
-// any.
+// any.  Add INCREASE to the file size and the memory size.
 
 void
-Output_segment::set_offset()
+Output_segment::set_offset(unsigned int increase)
 {
   gold_assert(this->type_ != elfcpp::PT_LOAD);
 
@@ -2524,6 +4031,7 @@ Output_segment::set_offset()
 
   if (this->output_data_.empty() && this->output_bss_.empty())
     {
+      gold_assert(increase == 0);
       this->vaddr_ = 0;
       this->paddr_ = 0;
       this->are_addresses_set_ = true;
@@ -2534,11 +4042,14 @@ Output_segment::set_offset()
       return;
     }
 
-  const Output_data* first;
-  if (this->output_data_.empty())
-    first = this->output_bss_.front();
-  else
-    first = this->output_data_.front();
+  // Find the first and last section by address.  The sections may
+  // have been sorted for the PT_LOAD segment.
+  const Output_data* first = NULL;
+  const Output_data* last_data = NULL;
+  const Output_data* last_bss = NULL;
+  this->find_first_and_last_list(&this->output_data_, &first, &last_data);
+  this->find_first_and_last_list(&this->output_bss_, &first, &last_bss);
+
   this->vaddr_ = first->address();
   this->paddr_ = (first->has_load_address()
                  ? first->load_address()
@@ -2549,21 +4060,58 @@ Output_segment::set_offset()
   if (this->output_data_.empty())
     this->filesz_ = 0;
   else
-    {
-      const Output_data* last_data = this->output_data_.back();
-      this->filesz_ = (last_data->address()
-                      + last_data->data_size()
-                      - this->vaddr_);
-    }
+    this->filesz_ = (last_data->address()
+                    + last_data->data_size()
+                    - this->vaddr_);
 
-  const Output_data* last;
-  if (this->output_bss_.empty())
-    last = this->output_data_.back();
-  else
-    last = this->output_bss_.back();
+  const Output_data* last = last_bss != NULL ? last_bss : last_data;
   this->memsz_ = (last->address()
                  + last->data_size()
                  - this->vaddr_);
+
+  this->filesz_ += increase;
+  this->memsz_ += increase;
+
+  // If this is a TLS segment, align the memory size.  The code in
+  // set_section_list ensures that the section after the TLS segment
+  // is aligned to give us room.
+  if (this->type_ == elfcpp::PT_TLS)
+    {
+      uint64_t segment_align = this->maximum_alignment();
+      gold_assert(this->vaddr_ == align_address(this->vaddr_, segment_align));
+      this->memsz_ = align_address(this->memsz_, segment_align);
+    }
+}
+
+// Look through a list of Output_data objects and find the first and
+// last by address.
+
+void
+Output_segment::find_first_and_last_list(const Output_data_list* pdl,
+                                        const Output_data** pfirst,
+                                        const Output_data** plast) const
+{
+  const Output_data* first = *pfirst;
+  const Output_data* last = *plast;
+  for (Output_data_list::const_iterator p = pdl->begin(); p != pdl->end(); ++p)
+    {
+      if (first == NULL
+         || (*p)->address() < first->address()
+         || ((*p)->address() == first->address()
+             && (*p)->data_size() < first->data_size()))
+       {
+         first = *p;
+         *pfirst = first;
+       }
+      if (last == NULL
+         || (*p)->address() > last->address()
+         || ((*p)->address() == last->address()
+             && (*p)->data_size() > last->data_size()))
+       {
+         last = *p;
+         *plast = last;
+       }
+    }
 }
 
 // Set the TLS offsets of the sections in the PT_TLS segment.
@@ -2701,8 +4249,7 @@ unsigned char*
 Output_segment::write_section_headers(const Layout* layout,
                                      const Stringpool* secnamepool,
                                      unsigned char* v,
-                                     unsigned int *pshndx
-                                      ACCEPT_SIZE_ENDIAN) const
+                                     unsigned int *pshndx) const
 {
   // Every section that is attached to a segment must be attached to a
   // PT_LOAD segment, so we only write out section headers for PT_LOAD
@@ -2710,14 +4257,12 @@ Output_segment::write_section_headers(const Layout* layout,
   if (this->type_ != elfcpp::PT_LOAD)
     return v;
 
-  v = this->write_section_headers_list
-      SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
-         layout, secnamepool, &this->output_data_, v, pshndx
-          SELECT_SIZE_ENDIAN(size, big_endian));
-  v = this->write_section_headers_list
-      SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
-          layout, secnamepool, &this->output_bss_, v, pshndx
-          SELECT_SIZE_ENDIAN(size, big_endian));
+  v = this->write_section_headers_list<size, big_endian>(layout, secnamepool,
+                                                        &this->output_data_,
+                                                        v, pshndx);
+  v = this->write_section_headers_list<size, big_endian>(layout, secnamepool,
+                                                        &this->output_bss_,
+                                                        v, pshndx);
   return v;
 }
 
@@ -2727,8 +4272,7 @@ Output_segment::write_section_headers_list(const Layout* layout,
                                           const Stringpool* secnamepool,
                                           const Output_data_list* pdl,
                                           unsigned char* v,
-                                          unsigned int* pshndx
-                                           ACCEPT_SIZE_ENDIAN) const
+                                          unsigned int* pshndx) const
 {
   const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
   for (Output_data_list::const_iterator p = pdl->begin();
@@ -2748,6 +4292,29 @@ Output_segment::write_section_headers_list(const Layout* layout,
   return v;
 }
 
+// Print the output sections to the map file.
+
+void
+Output_segment::print_sections_to_mapfile(Mapfile* mapfile) const
+{
+  if (this->type() != elfcpp::PT_LOAD)
+    return;
+  this->print_section_list_to_mapfile(mapfile, &this->output_data_);
+  this->print_section_list_to_mapfile(mapfile, &this->output_bss_);
+}
+
+// Print an output section list to the map file.
+
+void
+Output_segment::print_section_list_to_mapfile(Mapfile* mapfile,
+                                             const Output_data_list* pdl) const
+{
+  for (Output_data_list::const_iterator p = pdl->begin();
+       p != pdl->end();
+       ++p)
+    (*p)->print_to_mapfile(mapfile);
+}
+
 // Output_file methods.
 
 Output_file::Output_file(const char* name)
@@ -2760,6 +4327,42 @@ Output_file::Output_file(const char* name)
 {
 }
 
+// Try to open an existing file.  Returns false if the file doesn't
+// exist, has a size of 0 or can't be mmapped.
+
+bool
+Output_file::open_for_modification()
+{
+  // The name "-" means "stdout".
+  if (strcmp(this->name_, "-") == 0)
+    return false;
+
+  // Don't bother opening files with a size of zero.
+  struct stat s;
+  if (::stat(this->name_, &s) != 0 || s.st_size == 0)
+    return false;
+
+  int o = open_descriptor(-1, this->name_, O_RDWR, 0);
+  if (o < 0)
+    gold_fatal(_("%s: open: %s"), this->name_, strerror(errno));
+  this->o_ = o;
+  this->file_size_ = s.st_size;
+
+  // If the file can't be mmapped, copying the content to an anonymous
+  // map will probably negate the performance benefits of incremental
+  // linking.  This could be helped by using views and loading only
+  // the necessary parts, but this is not supported as of now.
+  if (!this->map_no_anonymous())
+    {
+      release_descriptor(o, true);
+      this->o_ = -1;
+      this->file_size_ = 0;
+      return false;
+    }
+
+  return true;
+}
+
 // Open the output file.
 
 void
@@ -2788,11 +4391,26 @@ Output_file::open(off_t file_size)
       else
        {
          struct stat s;
-         if (::stat(this->name_, &s) == 0 && s.st_size != 0)
-           unlink_if_ordinary(this->name_);
+         if (::stat(this->name_, &s) == 0
+             && (S_ISREG (s.st_mode) || S_ISLNK (s.st_mode)))
+           {
+             if (s.st_size != 0)
+               ::unlink(this->name_);
+             else if (!parameters->options().relocatable())
+               {
+                 // If we don't unlink the existing file, add execute
+                 // permission where read permissions already exist
+                 // and where the umask permits.
+                 int mask = ::umask(0);
+                 ::umask(mask);
+                 s.st_mode |= (s.st_mode & 0444) >> 2;
+                 ::chmod(this->name_, s.st_mode & ~mask);
+               }
+           }
 
-         int mode = parameters->output_is_object() ? 0666 : 0777;
-         int o = ::open(this->name_, O_RDWR | O_CREAT | O_TRUNC, mode);
+         int mode = parameters->options().relocatable() ? 0666 : 0777;
+         int o = open_descriptor(-1, this->name_, O_RDWR | O_CREAT | O_TRUNC,
+                                 mode);
          if (o < 0)
            gold_fatal(_("%s: open: %s"), this->name_, strerror(errno));
          this->o_ = o;
@@ -2823,14 +4441,32 @@ Output_file::resize(off_t file_size)
     {
       this->unmap();
       this->file_size_ = file_size;
-      this->map();
+      if (!this->map_no_anonymous())
+       gold_fatal(_("%s: mmap: %s"), this->name_, strerror(errno));
     }
 }
 
-// Map the file into memory.
+// Map an anonymous block of memory which will later be written to the
+// file.  Return whether the map succeeded.
 
-void
-Output_file::map()
+bool
+Output_file::map_anonymous()
+{
+  void* base = ::mmap(NULL, this->file_size_, PROT_READ | PROT_WRITE,
+                     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+  if (base != MAP_FAILED)
+    {
+      this->map_is_anonymous_ = true;
+      this->base_ = static_cast<unsigned char*>(base);
+      return true;
+    }
+  return false;
+}
+
+// Map the file into memory.  Return whether the mapping succeeded.
+
+bool
+Output_file::map_no_anonymous()
 {
   const int o = this->o_;
 
@@ -2843,28 +4479,52 @@ Output_file::map()
       || ::fstat(o, &statbuf) != 0
       || !S_ISREG(statbuf.st_mode)
       || this->is_temporary_)
-    {
-      this->map_is_anonymous_ = true;
-      base = ::mmap(NULL, this->file_size_, PROT_READ | PROT_WRITE,
-                    MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
-    }
-  else
-    {
-      // Write out one byte to make the file the right size.
-      if (::lseek(o, this->file_size_ - 1, SEEK_SET) < 0)
-        gold_fatal(_("%s: lseek: %s"), this->name_, strerror(errno));
-      char b = 0;
-      if (::write(o, &b, 1) != 1)
-        gold_fatal(_("%s: write: %s"), this->name_, strerror(errno));
+    return false;
 
-      // Map the file into memory.
-      this->map_is_anonymous_ = false;
-      base = ::mmap(NULL, this->file_size_, PROT_READ | PROT_WRITE,
-                    MAP_SHARED, o, 0);
-    }
+  // Ensure that we have disk space available for the file.  If we
+  // don't do this, it is possible that we will call munmap, close,
+  // and exit with dirty buffers still in the cache with no assigned
+  // disk blocks.  If the disk is out of space at that point, the
+  // output file will wind up incomplete, but we will have already
+  // exited.  The alternative to fallocate would be to use fdatasync,
+  // but that would be a more significant performance hit.
+  if (::posix_fallocate(o, 0, this->file_size_) < 0)
+    gold_fatal(_("%s: %s"), this->name_, strerror(errno));
+
+  // Map the file into memory.
+  base = ::mmap(NULL, this->file_size_, PROT_READ | PROT_WRITE,
+               MAP_SHARED, o, 0);
+
+  // The mmap call might fail because of file system issues: the file
+  // system might not support mmap at all, or it might not support
+  // mmap with PROT_WRITE.
   if (base == MAP_FAILED)
-    gold_fatal(_("%s: mmap: %s"), this->name_, strerror(errno));
+    return false;
+
+  this->map_is_anonymous_ = false;
   this->base_ = static_cast<unsigned char*>(base);
+  return true;
+}
+
+// Map the file into memory.
+
+void
+Output_file::map()
+{
+  if (this->map_no_anonymous())
+    return;
+
+  // The mmap call might fail because of file system issues: the file
+  // system might not support mmap at all, or it might not support
+  // mmap with PROT_WRITE.  I'm not sure which errno values we will
+  // see in all cases, so if the mmap fails for any reason and we
+  // don't care about file contents, try for an anonymous map.
+  if (this->map_anonymous())
+    return;
+
+  gold_fatal(_("%s: mmap: failed to allocate %lu bytes for output file: %s"),
+             this->name_, static_cast<unsigned long>(this->file_size_),
+             strerror(errno));
 }
 
 // Unmap the file from memory.
@@ -2886,15 +4546,20 @@ Output_file::close()
   if (this->map_is_anonymous_ && !this->is_temporary_)
     {
       size_t bytes_to_write = this->file_size_;
+      size_t offset = 0;
       while (bytes_to_write > 0)
         {
-          ssize_t bytes_written = ::write(this->o_, this->base_, bytes_to_write);
+          ssize_t bytes_written = ::write(this->o_, this->base_ + offset,
+                                          bytes_to_write);
           if (bytes_written == 0)
             gold_error(_("%s: write: unexpected 0 return-value"), this->name_);
           else if (bytes_written < 0)
             gold_error(_("%s: write: %s"), this->name_, strerror(errno));
           else
-            bytes_to_write -= bytes_written;
+            {
+              bytes_to_write -= bytes_written;
+              offset += bytes_written;
+            }
         }
     }
   this->unmap();
@@ -2915,6 +4580,7 @@ Output_file::close()
 template
 off_t
 Output_section::add_input_section<32, false>(
+    Layout* layout,
     Sized_relobj<32, false>* object,
     unsigned int shndx,
     const char* secname,
@@ -2927,6 +4593,7 @@ Output_section::add_input_section<32, false>(
 template
 off_t
 Output_section::add_input_section<32, true>(
+    Layout* layout,
     Sized_relobj<32, true>* object,
     unsigned int shndx,
     const char* secname,
@@ -2939,6 +4606,7 @@ Output_section::add_input_section<32, true>(
 template
 off_t
 Output_section::add_input_section<64, false>(
+    Layout* layout,
     Sized_relobj<64, false>* object,
     unsigned int shndx,
     const char* secname,
@@ -2951,6 +4619,7 @@ Output_section::add_input_section<64, false>(
 template
 off_t
 Output_section::add_input_section<64, true>(
+    Layout* layout,
     Sized_relobj<64, true>* object,
     unsigned int shndx,
     const char* secname,
@@ -2959,6 +4628,86 @@ Output_section::add_input_section<64, true>(
     bool have_sections_script);
 #endif
 
+#ifdef HAVE_TARGET_32_LITTLE
+template
+class Output_reloc<elfcpp::SHT_REL, false, 32, false>;
+#endif
+
+#ifdef HAVE_TARGET_32_BIG
+template
+class Output_reloc<elfcpp::SHT_REL, false, 32, true>;
+#endif
+
+#ifdef HAVE_TARGET_64_LITTLE
+template
+class Output_reloc<elfcpp::SHT_REL, false, 64, false>;
+#endif
+
+#ifdef HAVE_TARGET_64_BIG
+template
+class Output_reloc<elfcpp::SHT_REL, false, 64, true>;
+#endif
+
+#ifdef HAVE_TARGET_32_LITTLE
+template
+class Output_reloc<elfcpp::SHT_REL, true, 32, false>;
+#endif
+
+#ifdef HAVE_TARGET_32_BIG
+template
+class Output_reloc<elfcpp::SHT_REL, true, 32, true>;
+#endif
+
+#ifdef HAVE_TARGET_64_LITTLE
+template
+class Output_reloc<elfcpp::SHT_REL, true, 64, false>;
+#endif
+
+#ifdef HAVE_TARGET_64_BIG
+template
+class Output_reloc<elfcpp::SHT_REL, true, 64, true>;
+#endif
+
+#ifdef HAVE_TARGET_32_LITTLE
+template
+class Output_reloc<elfcpp::SHT_RELA, false, 32, false>;
+#endif
+
+#ifdef HAVE_TARGET_32_BIG
+template
+class Output_reloc<elfcpp::SHT_RELA, false, 32, true>;
+#endif
+
+#ifdef HAVE_TARGET_64_LITTLE
+template
+class Output_reloc<elfcpp::SHT_RELA, false, 64, false>;
+#endif
+
+#ifdef HAVE_TARGET_64_BIG
+template
+class Output_reloc<elfcpp::SHT_RELA, false, 64, true>;
+#endif
+
+#ifdef HAVE_TARGET_32_LITTLE
+template
+class Output_reloc<elfcpp::SHT_RELA, true, 32, false>;
+#endif
+
+#ifdef HAVE_TARGET_32_BIG
+template
+class Output_reloc<elfcpp::SHT_RELA, true, 32, true>;
+#endif
+
+#ifdef HAVE_TARGET_64_LITTLE
+template
+class Output_reloc<elfcpp::SHT_RELA, true, 64, false>;
+#endif
+
+#ifdef HAVE_TARGET_64_BIG
+template
+class Output_reloc<elfcpp::SHT_RELA, true, 64, true>;
+#endif
+
 #ifdef HAVE_TARGET_32_LITTLE
 template
 class Output_data_reloc<elfcpp::SHT_REL, false, 32, false>;