[Bug tree-optimization/28868] [4.3/4.4/4.5 Regression] Not eliminating the PHIs which have the same arguments

2009-03-31 Thread jsm28 at gcc dot gnu dot org 


--- Comment #17 from jsm28 at gcc dot gnu dot org  2009-03-31 19:41 ---
Closing 4.2 branch.


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jsm28 at gcc dot gnu dot org changed:

   What|Removed |Added

Summary|[4.2/4.3/4.4/4.5 Regression]|[4.3/4.4/4.5 Regression] Not
   |Not eliminating the PHIs|eliminating the PHIs which
   |which have the same |have the same arguments
   |arguments   |
   Target Milestone|4.2.5   |4.3.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28868

[Bug tree-optimization/28868] [4.3/4.4/4.5 Regression] Not eliminating the PHIs which have the same arguments

2009-04-04 Thread rguenth at gcc dot gnu dot org 


--- Comment #18 from rguenth at gcc dot gnu dot org  2009-04-04 17:57 
---
Patch posted:
http://gcc.gnu.org/ml/gcc-patches/2009-04/msg00311.html

it will replace redundant PHI nodes with a copy, so

:
  # c_1 = PHI 
  # d_2 = PHI 
  D.1599_10 = c_1 + d_2;

will become

:
  # c_1 = PHI 
  d_2 = c_1
  D.1599_10 = c_1 + d_2;

to not immediately trigger PR23821 (of course the next copyprop will
happily propagate c_1 into all uses of d_2).  It does replace single-uses
though, which does not increase register pressure.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28868

[Bug tree-optimization/28868] [4.3/4.4/4.5 Regression] Not eliminating the PHIs which have the same arguments

2009-04-06 Thread rguenth at gcc dot gnu dot org 


--- Comment #19 from rguenth at gcc dot gnu dot org  2009-04-06 14:55 
---
Subject: Bug 28868

Author: rguenth
Date: Mon Apr  6 14:55:31 2009
New Revision: 145607

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=145607
Log:
2009-04-06  Richard Guenther  

PR tree-optimization/28868
* tree-ssa-pre.c (inserted_phi_names): New bitmap to keep track
of which PHI results we inserted.
(insert_into_preds_of_block): Record inserted PHIs.
(eliminate): Eliminate redundant PHI nodes.
(init_pre): Init inserted_phi_names.

* gcc.dg/tree-ssa/ssa-fre-21.c: New testcase.
* gcc.dg/tree-ssa/ssa-sccvn-1.c: Adjust.
* gcc.dg/tree-ssa/ssa-sccvn-2.c: Likewise.
* gcc.dg/tree-ssa/ssa-sccvn-4.c: Likewise.

Added:
trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-23.c
Modified:
trunk/gcc/ChangeLog
trunk/gcc/testsuite/ChangeLog
trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-sccvn-1.c
trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-sccvn-2.c
trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-sccvn-4.c
trunk/gcc/tree-ssa-pre.c


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28868