diff mbox

RFA: Compare Elimination Pass: Fix use of dataflow info

Message ID m3obxt9kvh.fsf@redhat.com
State New
Headers show

Commit Message

Nick Clifton Oct. 7, 2011, 10:06 a.m. UTC 
Hi Richard, Hi Paulo,

  Following Paulo's suggestion, here is a patch to remove the calls to
  df_analyze from the compare-elimination pass, and to use
  df_get_live_[in/out].  I can confirm that with this patch applied PR
  49801 is fixed.

  OK to apply ?  For mainline and the 4.6 branch ?

Cheers
  Nick

gcc/ChangeLog
2011-10-07  Nick Clifton  <nickc@redhat.com>

	PR middle-end/49801
	* compare-elim.c (find_comparisons_in_bb): Use df_get_live_in and
	df_get_live_out instead of accessing the bitmaps directly.
	(execute_compare_elim_after_reload): Remove calls to df_set_flags,
	df_live_add_problem and df_analyze.

Comments

Paolo Bonzini Oct. 7, 2011, 10:29 a.m. UTC | #1 
On 10/07/2011 12:06 PM, Nick Clifton wrote:
> -  df_analyze ();
> -
>     gcc_checking_assert (all_compares == NULL);
>

Ok except that this particular df_analyze should stay.  If it doesn't 
fix the bug, please try the parts of rth's patch that add the gate and 
the TODO_df_finish flag.

Paolo
diff mbox

Patch

Index: gcc/compare-elim.c
===================================================================
--- gcc/compare-elim.c	(revision 179647)
+++ gcc/compare-elim.c	(working copy)
@@ -356,7 +356,7 @@ 
 
       /* Look to see if the flags register is live outgoing here, and
 	 incoming to any successor not part of the extended basic block.  */
-      if (bitmap_bit_p (&DF_LIVE_BB_INFO (bb)->out, targetm.flags_regnum))
+      if (bitmap_bit_p (df_get_live_out (bb), targetm.flags_regnum))
 	{
 	  edge e;
 	  edge_iterator ei;
@@ -364,7 +364,7 @@ 
 	  FOR_EACH_EDGE (e, ei, bb->succs)
 	    {
 	      basic_block dest = e->dest;
-	      if (bitmap_bit_p (&DF_LIVE_BB_INFO (dest)->in,
+	      if (bitmap_bit_p (df_get_live_in (bb),
 				targetm.flags_regnum)
 		  && !single_pred_p (dest))
 		{
@@ -580,10 +580,6 @@ 
 static unsigned int
 execute_compare_elim_after_reload (void)
 {
-  df_set_flags (DF_DEFER_INSN_RESCAN);
-  df_live_add_problem ();
-  df_analyze ();
-
   gcc_checking_assert (all_compares == NULL);
 
   /* Locate all comparisons and their uses, and eliminate duplicates.  */
@@ -602,8 +598,6 @@ 
 
       VEC_free (comparison_struct_p, heap, all_compares);
       all_compares = NULL;
-
-      df_analyze ();
     }
 
   return 0;