Group text sections with prefixes .text.unlikely,.text.hot and .text.startup

by default.


2012-12-18  Sriraman Tallam  <tmsriram@google.com>

	* layout.cc (Layout::is_section_name_prefix_grouped): New function.
	* layout.h (Layout::is_section_name_prefix_grouped): New function.
	* output.cc (Output_section::add_input_section): Check if section
	name contains special prefix.  Keep input sections to sort such
	sections.
	(Output_section::Input_section_sort_section_order_index_compare
	 ::operator()): Group sections according to prefixes.
	* (Output_section::sort_attached_input_sections): Add condition
	to Input_section_entry constructor call.
	* testsuite/Makefile.am (text_section_grouping): New test.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/text_section_grouping.cc: New file.
	* testsuite/text_section_grouping.sh: New file.

1 files changed, 14 insertions, 0 deletions

diff --git a/gold/layout.cc b/gold/layout.cc
index 60fabb8b819..62b4cadf9d3 100644
--- a/gold/layout.cc
+++ b/gold/layout.cc
@@ -2409,6 +2409,20 @@ Layout::relaxation_loop_body(
   return off;
 }
 
+// By default, gold groups input sections with certain prefixes.  This 
+// function returns true if this section name NAME contains such a prefix.
+
+bool
+Layout::is_section_name_prefix_grouped(const char *name)
+{
+  if (is_prefix_of(".text.unlikely", name)
+      || is_prefix_of(".text.startup", name)
+      || is_prefix_of(".text.hot", name))
+    return true;
+
+  return false;
+}
+
 // Search the list of patterns and find the postion of the given section
 // name in the output section.  If the section name matches a glob
 // pattern and a non-glob name, then the non-glob position takes