2009-09-17 Doug Kwan <dougkwan@google.com>

	* debug.h (DEBUG_RELAXATION): New constant.
	(DEBUG_ALL): Add DEBUG_RELAXATION.
	(debug_string_to_enum): Add relaxation debug option.
	* layout.cc
	(Layout::Relaxation_debug_check::check_output_data_for_reset_values,
	Layout::Relaxation_debug_check::read_sections,
	Layout::Relaxation_debug_check::read_sections): New method definitions.
	(Layout::Layout): Initialize data members
	record_output_section_data_from_scrips_,
	script_output_section_data_list_ and relaxation_debug_check_.
	(Layout::save_segments, Layout::restore_segments,
	Layout::clean_up_after_relaxation, Layout::prepare_for_relaxation,
	Layout::relaxation_loop_body): New method definitions.
	(Layout::finalize): Support relaxation.  Move section layout code to
	Layout::relaxation_loop_body.
	(Layout::set_asection_address_from_script): Move code for orphan
	section placement out.
	(Layout::place_orphan_sections_in_script): New method definition.
	* layout.h (Output_segment_headers, Output_file_header):
	New forward class declarations.
	(Layout::~Layout): Define.
	(Layout::new_output_section_data_from_script): New method definition.
	(Layout::place_orphan_sections_in_script): New method declaration.
	(Layout::Segment_states): New type declaration.
	(Layout::save_segments, Layout::restore_segments,
	Layout::clean_up_after_relaxation, Layout::prepare_for_relaxation,
	Layout::relaxation_loop_body): New method declarations.
	(Layout::Output_section_data_list): New type declaration.
	(Layout::Relaxation_debug_check): New class definition.
	(Layout::record_output_section_data_from_script_,
	Layout::script_output_section_data_list_, Layout::segment_states_,
	Layout::relaxation_debug_check_): New data members.
	* output.cc: (Output_section_headers::do_size): New method definition.
	(Output_section_headers::Output_section_headers): Move size
	computation to Output_section_headers::do_size.
	(Output_segment_headers::do_size): New method definition.
	(Output_file_header::Output_file_header): Move size computation to
	Output_file_header::do_size and call it.
	(Output_file_header::do_size): New method definition.
	(Output_data_group::Output_data_group): Adjust call to
	Output_section_data.
	(Output_data_dynamic::set_final_data_size): Add DT_NULL tag only once.
	(Output_symtab_xindex::do_write): Add array bound check.
 	(Output_section::Input_section::print_to_mapfile): Handle
	RELAXED_INPUT_SECTION_CODE.
	(Output_section::Output_section): Initialize data member checkpoint_.
	(Output_section::~Output_section): Delete checkpoint object pointed
	by checkpoint_.
	(Output_section::add_input_section): Always add an Input_section if
	relaxing.
	(Output_section::add_merge_input_section): Add assert.
	(Output_section::relax_input_section): New method definition.
	(Output_section::set_final_data_size): Set load address to zero for
	an unallocated section.
	(Output_section::do_address_and_file_offset_have_reset_values):
	New method definition.
	(Output_section::Input_section_sort_enty::Input_section_sort_enty):
	Handle relaxed input section.
	(Output_section::sort_attached_input_sections): Checkpoint input
	section list lazily.
	(Output_section::get_input_sections): Change type of input_sections to
	list of Simple_input_section pointers.  Checkpoint input section list
	lazily.  Also handle relaxed input sections.
	(Output_section::add_input_section_for_script): Take a reference to
	a Simple_input_section object instead of Relobj pointer and section
	index as parameter.  Handle relaxed input sections.
	(Output_section::save_states, Output_section::restore_states): New
	method definitions.
	* output.h (Output_data::Output_data): Initialize is_data_size_fixed_.
	(Output_data::is_data_size_fixed): New method definition.
	(Output_data::reset_addresss_and_file_offset): Do not reset data size
	if it is fixed.
	(Output_data::address_and_file_offset_have_reset_values): New method
	definition.
	(Output_data::do_address_and_file_offset_have_reset_values): New method
	definition.
	(Output_data::set_data_size): Check that data size is not fixed.
	(Output_data::fix_data_size): New method definition.
	(Output_data::is_data_size_fixed_): New data member.
	(Output_section_headers::set_final_data_size): New method definition.
	(Output_section_headers::do_size): New method declaration.
	(Output_segment_headers::set_final_data_size): New method definition.
	(Output_segment_headers::do_size): New method declaration.
	(Output_file_header::set_final_data_size)::New method definition.
	(Output_file_header::do_size)::New method declaration.
	(Output_section_data::Output_section_data): Add new parameter
	is_data_size_fixed and use it to fix data size.
	(Output_data_const::Output_data_const): Adjust call to base class
	constructor and fix data size.
	(Output_data_const_buffer::Output_data_const_buffer): Adjust call to
	base class constructor and fix data size.
	(Output_data_fixed_space::Output_data_fixed_space): Adjust call to
	base class constructor and fix data size.
	(Output_data_zero_fill::Output_data_zero_fill): Adjust call to base
	class constructor and fix data size.
	(Output_data_group::set_final_data_size): New method definition.
	(Output_data_dynamic::Dynamic_entry::tag): New method definition.
	(Output_symtab_xindex::Output_symtab_xindex): Adjust call to base
	class constructor and fix data size.
	(Output_relaxed_input_section): New class definition.
	(Output_section::Simple_input_section): New class definition.
	(Output_section::get_input_sections): Adjust parameter list.
	(Output_section::add_input_section_for_script): Same.
	(Output_section::save_states, Output_section::restore_states,
	Output_section::do_address_and_file_offset_have_reset_values,
	(Output_section::Input_section::Input_section): Handle
	RELAXED_INPUT_SECTION_CODE.  Add new overload for
	Output_relaxed_input_section.
	(Output_section::Input_section::is_input_section,
	Output_section::Input_section::set_output_section): Handle relaxed
	input section.
	(Output_section::Input_section::is_relaxed_input_section,
	Output_section::Input_section::output_section_data,
	Output_section::Input_section::relaxed_input_section): New method
	definitions.
	(Output_section::Input_section::RELAXED_INPUT_SECTION_CODE): New enum
	value.
	(Output_section::Input_section::u1_): Update comments.
	(Output_section::Input_section::u2_): Add new union member poris.
	(Output_section::Checkpoint_output_section): New classs definition.
	(Output_section::relax_input_section): New method declaration.
	(Output_section::checkpoint_): New data member.
	(Output_segment): Update comments.
	(Output_segment::Output_segment): Un-privatize copy constructor.
	(Output_segment::operator=): Un-privatize.
	* script-sections.cc (Output_section_element::Input_section_list):
	Change element type to Output_section::Simple_input_section.
	(Output_section_element_dot_assignment::set_section_addresses):
	Register output section data for relaxation clean up.
	(Output_data_exression::Output_data_expression): Adjust call to base
	constructor to fix data size.
	(Output_section_element_data::set_section_addresses): Register
	Output_data_expression object for relaxation clean up.
	(struct Input_section_info): Replace Relobj pointer and section index
	pair with Output_section::Simple_input_section and Convert struct to a
	class.
	(Input_section_sorter::operator()): Adjust access to
	Input_section_info data member to use accessors.
	(Output_section_element_input::set_section_addresses): Use layout
	parameter.  Adjust code to use Output_section::Simple_input_section
	and Input_secction_info classes.  Register filler for relaxation
	clean up.
	(Orphan_output_section::set_section_addresses): Replace Relobj pointer
	and section index pair with Output_section::Simple_input_section
	class.  Adjust code accordingly.
	(Phdrs_element::release_segment): New method definition.
	(Script_sections::attach_sections_using_phdrs_clause): Do not modify
	segment list.
	(Script_sections::release_segments): New method definition.
	* gold/script-sections.h (Script_sections::release_segments): New
	method declaration.
	* gold/target.h (Target::may_relax, Target::relax,
	Target::do_may_relax, Target::do_relax): New method definitions.

1 files changed, 33 insertions, 0 deletions

diff --git a/gold/target.h b/gold/target.h
index c9b07a8..ac59fb2 100644
--- a/gold/target.h
+++ b/gold/target.h
@@ -36,6 +36,7 @@
 #include "elfcpp.h"
 #include "options.h"
 #include "parameters.h"
+#include "debug.h"
 
 namespace gold
 {
@@ -223,6 +224,28 @@ class Target
 		  off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr)
   { return this->do_make_elf_object(name, input_file, offset, ehdr); }
 
+  // Return true if target wants to perform relaxation.
+  bool
+  may_relax() const
+  {
+    // Run the dummy relaxation pass twice if relaxation debugging is enabled.
+    if (is_debugging_enabled(DEBUG_RELAXATION))
+      return true;
+
+     return this->do_may_relax();
+  }
+
+  // Perform a relaxation pass.  Return true if layout may be changed.
+  bool
+  relax(int pass)
+  {
+    // Run the dummy relaxation pass twice if relaxation debugging is enabled.
+    if (is_debugging_enabled(DEBUG_RELAXATION))
+      return pass < 2;
+
+    return this->do_relax(pass);
+  } 
+
  protected:
   // This struct holds the constant information for a child class.  We
   // use a struct to avoid the overhead of virtual function calls for
@@ -339,6 +362,16 @@ class Target
 		     off_t offset, const elfcpp::Ehdr<64, true>& ehdr);
 #endif
 
+  // Virtual function which may be overriden by the child class.
+  virtual bool
+  do_may_relax() const
+  { return parameters->options().relax(); }
+
+  // Virtual function which may be overriden by the child class.
+  virtual bool
+  do_relax(int)
+  { return false; }
+
  private:
   // The implementations of the four do_make_elf_object virtual functions are
   // almost identical except for their sizes and endianity.  We use a template.