regrename.c: Add general comment describing the pass.

	* regrename.c: Add general comment describing the pass.
	(struct du_head): Remove 'length' field.
	(get_element, merge_sort_comparison, merge, sort_du_head): Remove.
	(regrename_optimize): Do not sort chains.  Rework comments, add others.
	Force renaming to the preferred class (if any) in the first pass and do
	not consider registers that belong to it in the second pass.
	(create_new_chain): Do not set 'length' field.
	(scan_rtx_reg): Likewise.

From-SVN: r168404

gcc/ChangeLog

+2011-01-02  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* regrename.c: Add general comment describing the pass.
+	(struct du_head): Remove 'length' field.
+	(get_element, merge_sort_comparison, merge, sort_du_head): Remove.
+	(regrename_optimize): Do not sort chains.  Rework comments, add others.
+	Force renaming to the preferred class (if any) in the first pass and do
+	not consider registers that belong to it in the second pass.
+	(create_new_chain): Do not set 'length' field.
+	(scan_rtx_reg): Likewise.
+
 2011-01-02  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/47140
@@ -6,9 +17,8 @@
 	to bit_value_binop.
 
 	PR rtl-optimization/47028
-	* cfgexpand.c (gimple_expand_cfg): Insert entry edge
-	insertions after parm_birth_insn instead of at the beginning
-	of first bb.
+	* cfgexpand.c (gimple_expand_cfg): Insert entry edge insertions after
+	parm_birth_insn instead of at the beginning of first bb.
 
 2011-01-02  Mingjie Xing  <mingjie.xing@gmail.com>
 
@@ -18,14 +28,13 @@
 
 2011-01-01  Jan Hubicka  <jh@suse.cz>
 
-	* tree-loop-distribution.c (tree_loop_distribution): Do not
-	use freed memory.
+	* tree-loop-distribution.c (tree_loop_distribution): Do not use freed
+	memory.
 
 2011-01-01  Kai Tietz  <kai.tietz@onevision.com>
 
 	PR target/38662
-	* tree.c (type_hash_eq): Call
-	language hook for METHOD_TYPEs, too.
+	* tree.c (type_hash_eq): Call language hook for METHOD_TYPEs, too.
 
 
 Copyright (C) 2011 Free Software Foundation, Inc.