2010-05-23 Doug Kwan <dougkwan@google.com>

* arm.cc (Arm_input_section::do_output_offset): Use convert_types
	instead of a cast.
	(Target_arm::apply_cortex_a8_workaround): Rewrite a conditional branch
	with a direct branch, not a conditional branch, to a stub.
	* merge.cc (Output_merge_base::record_input_section): New method
	defintion.
	(Output_merge_data::do_add_input_section): Record input section if
	keeps-input-sections flag is set.
	(Output_merge_string::do_add_input_section): Ditto.
	* merge.h (Output_merge_base::Output_merge_base): Initialize new data
	members KEEPS_INPUT_SECTIONS_, FIRST_RELOBJ_, FIRST_SHNDX_ and
	INPUT_SECTIONS_.
	(Output_merge_base::keeps_input_sections,
	Output_merge_base::set_keeps_input_sections,
	Output_merge_base::first_relobj, Output_merge_base::first_shndx): New
	method definitions.
	(Output_merge_base::Input_sections): New type declaration.
	(Output_merge_base::input_sections_begin,
	Output_merge_base::input_sections_end,
	Output_merge_base::do_set_keeps_input_sections): New method definitions.
	(Output_merge_base::bool keeps_input_sections_,
	Output_merge_base::first_relobj_, Output_merge_base::first_shndx_,
	Output_merge_base::input_sections_): New data members.
	(Output_merge_data::do_set_keeps_input_sections): New method
	defintion.
	(Output_merge_string::do_set_keeps_input_sections): Ditto.
	* output.cc (Output_section::Input_section::relobj): Move method
	defintion from class declaration to here and handle merge sections.
	(Output_section::Input_section::shndx): Ditto.
	(Output_section::Output_section): Remove initializations of removed
	data members and initialize new data member LOOKUP_MAPS_.
	(Output_section::add_input_section): Set keeps-input-sections flag
	for a newly created merge output section as appropriate.  Adjust code
	to use Output_section_lookup_maps class.
	(Output_section::add_relaxed_input_section): Adjst code for lookup
	maps code refactoring.
 	(Output_section::add_merge_input_section): Add a new parameter
	KEEPS_INPUT_SECTION.  Adjust code to use Output_section_lookup_maps
	class.  If adding input section to a newly created merge output
	section fails, remove the new merge section.
	(Output_section::convert_input_sections_in_list_to_relaxed_input_sections):
	Adjust code for use of the Output_section_lookup_maps class.
 	(Output_section::find_merge_section): Ditto.
	(Output_section::build_lookup_maps): New method defintion.
 	(Output_section::find_relaxed_input_section): Adjust code to use
	Output_section_lookup_maps class.
	(Output_section::get_input_sections): Export merge sections.  Adjust
	code to use Output_section_lookup_maps class.
	(Output_section:::add_script_input_section): Adjust code to use
	Output_section_lookup_maps class.  Update lookup maps for merge
	sections also.
	(Output_section::discard_states): Use Output_section_lookup_maps.
	(Output_section::restore_states): Same.
	* output.h (Merge_section_properties): Move class defintion out of
	Output_section.
	(Output_section_lookup_maps): New class.
	(Output_section::Input_section::is_merge_section): New method
	defintion.
	(Output_section::Input_section::relobj): Move defintion out of class
	defintion.  Declare method only.
	(Output_section::Input_section::shndx): Ditto.
	(Output_section::Input_section::output_merge_base): New method defintion.
     	(Output_section::Input_section::u2_.pomb): New union field.
	(Output_section::Merge_section_by_properties_map,
	Output_section::Output_section_data_by_input_section_map,
	Output_section::Ouptut_relaxed_input_section_by_input_section_map):
	Remove types.
   	(Output_section::add_merge_input_section): Add new parameter
	KEEPS_INPUT_SECTIONS.
	(Output_section::build_lookup_maps): New method declaration.
	(Output_section::merge_section_map_,
	Output_section::merge_section_by_properties_map_,
	Output_section::relaxed_input_section_map_,
	Output_section::is_relaxed_input_section_map_valid_): Remove data
	members.
	(Output_section::lookup_maps_): New data member.

gold/merge.h

@@ -216,7 +216,9 @@ class Output_merge_base : public Output_section_data
 {
  public:
   Output_merge_base(uint64_t entsize, uint64_t addralign)
-    : Output_section_data(addralign), merge_map_(), entsize_(entsize)
+    : Output_section_data(addralign), merge_map_(), entsize_(entsize),
+      keeps_input_sections_(false), first_relobj_(NULL), first_shndx_(-1),
+      input_sections_()
   { }
 
   // Return the entry size.
@@ -230,6 +232,52 @@ class Output_merge_base : public Output_section_data
   is_string()
   { return this->do_is_string(); }
 
+  // Whether this keeps input sections.
+  bool
+  keeps_input_sections() const
+  { return this->keeps_input_sections_; }
+
+  // Set the keeps-input-sections flag.  This is virtual so that sub-classes
+  // can perform additional checks.
+  void
+  set_keeps_input_sections()
+  { this->do_set_keeps_input_sections(); }
+
+  // Return the object of the first merged input section.  This used
+  // for script processing.  This is NULL if merge section is empty.
+  Relobj*
+  first_relobj() const
+  { return this->first_relobj_; }
+
+  // Return the section index of the first merged input section.  This
+  // is used for script processing.  This is valid only if merge section
+  // is not valid.
+  unsigned int
+  first_shndx() const
+  { 
+    gold_assert(this->first_relobj_ != NULL);
+    return this->first_shndx_;
+  }
+ 
+  // Set of merged input sections.
+  typedef Unordered_set<Section_id, Section_id_hash> Input_sections;
+
+  // Beginning of merged input sections.
+  Input_sections::const_iterator
+  input_sections_begin() const
+  {
+    gold_assert(this->keeps_input_sections_);
+    return this->input_sections_.begin();
+  }
+
+  // Beginning of merged input sections.
+  Input_sections::const_iterator
+  input_sections_end() const
+  {
+    gold_assert(this->keeps_input_sections_);
+    return this->input_sections_.end();
+  }
+ 
  protected:
   // Return the output offset for an input offset.
   bool
@@ -257,6 +305,15 @@ class Output_merge_base : public Output_section_data
   do_is_string()
   { return false; }
 
+  // This may be overridden by the child class.
+  virtual void
+  do_set_keeps_input_sections()
+  { this->keeps_input_sections_ = true; }
+
+  // Record the merged input section for script processing.
+  void
+  record_input_section(Relobj* relobj, unsigned int shndx);
+
  private:
   // A mapping from input object/section/offset to offset in output
   // section.
@@ -264,6 +321,15 @@ class Output_merge_base : public Output_section_data
   // The entry size.  For fixed-size constants, this is the size of
   // the constants.  For strings, this is the size of a character.
   uint64_t entsize_;
+  // Whether we keep input sections.
+  bool keeps_input_sections_;
+  // Object of the first merged input section.  We use this for script
+  // processing.
+  Relobj* first_relobj_;
+  // Section index of the first merged input section. 
+  unsigned int first_shndx_;
+  // Input sections.  We only keep them is keeps_input_sections_ is true.
+  Input_sections input_sections_;
 };
 
 // Handle SHF_MERGE sections with fixed-size constant data.
@@ -303,6 +369,14 @@ class Output_merge_data : public Output_merge_base
   void
   do_print_merge_stats(const char* section_name);
 
+  // Set keeps-input-sections flag.
+  void
+  do_set_keeps_input_sections()
+  {
+    gold_assert(this->input_count_ == 0);
+    Output_merge_base::do_set_keeps_input_sections();
+  }
+
  private:
   // We build a hash table of the fixed-size constants.  Each constant
   // is stored as a pointer into the section data we are accumulating.
@@ -440,6 +514,14 @@ class Output_merge_string : public Output_merge_base
   do_is_string()
   { return true; }
 
+  // Set keeps-input-sections flag.
+  void
+  do_set_keeps_input_sections()
+  {
+    gold_assert(this->input_count_ == 0);
+    Output_merge_base::do_set_keeps_input_sections();
+  }
+
  private:
   // The name of the string type, for stats.
   const char*