[Bug tree-optimization/28868] [4.3/4.4/4.5 Regression] Not eliminating the PHIs which have the same arguments
--- Comment #17 from jsm28 at gcc dot gnu dot org 2009-03-31 19:41 --- Closing 4.2 branch. -- 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
--- 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. -- 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
--- 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 -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28868