[Bug tree-optimization/53226] [4.8 Regression] Endless loop in forwprop

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53226

--- Comment #15 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-05-09 
12:19:41 UTC ---
Author: jakub
Date: Wed May  9 12:19:34 2012
New Revision: 187328

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=187328
Log:
    PR tree-optimization/53226
    * tree-ssa-forwprop.c (ssa_forward_propagate_and_combine): Remove
    prev and prev_initialized vars, gimple_set_plf (stmt, GF_PLF_1, false)
    before processing it and gimple_set_plf (stmt, GF_PLF_1, true) if it
    doesn't need to be revisited, look for earliest stmt with
    !gimple_plf (stmt, GF_PLF_1) if something changed.

    * gcc.c-torture/compile/pr53226.c: New test.

Added:
    trunk/gcc/testsuite/gcc.c-torture/compile/pr53226.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-forwprop.c