[Bug tree-optimization/52548] missed PRE optimization when function call follows to-be hoisted variable

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52548

--- Comment #6 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-03-22 
13:15:04 UTC ---
Author: rguenth
Date: Thu Mar 22 13:14:54 2012
New Revision: 185691

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=185691
Log:
2012-03-22  Richard Guenther  <rguent...@suse.de>

    PR tree-optimization/52548
    * tree-ssa-pre.c (valid_in_sets): Remove handling of invalidation
    because of clobbers.
    (prune_clobbered_mems): New function.
    (compute_antic_aux): Use it to prune ANTIC_OUT.
    (compute_partial_antic_aux): Use it to prune PA_IN.
    (compute_avail): Only insert expressions into EXP_GEN that
    are not invalidated when translated up to the beginning of
    the block.

    * gcc.dg/tree-ssa/ssa-pre-29.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-pre-29.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-pre.c