[dataflow] remove useless call from fwprop

Paolo Bonzini paolo.bonzini@lu.unisi.ch
Wed Mar 28 09:48:00 GMT 2007


This is one of the most expensive df_* calls, and it costs 1%
of compilation time.  No kidding.

The call is not necessary anymore.  fwprop can process the uses in
whatever order they are, until it reaches a fixed point.  It does
need the refs to be ordered, but computing use-def chains already
does that.

Ok?

Paolo

2007-03-28  Paolo Bonzini  <bonzini@gnu.org.

	* fwprop.c (fwprop_init): Don't call df_maybe_reorganize_use_refs.

Index: fwprop.c
===================================================================
--- fwprop.c    (revision 123155)
+++ fwprop.c    (working copy)
@@ -933,7 +933,6 @@ fwprop_init (void)
   df_set_flags (DF_EQ_NOTES);
   df_chain_add_problem (DF_UD_CHAIN);
   df_analyze ();
-  df_maybe_reorganize_use_refs (DF_REF_ORDER_BY_INSN_WITH_NOTES);
   df_set_flags (DF_DEFER_INSN_RESCAN);
 }
 



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