[Bug tree-optimization/81555] [5/6/7/8 Regression] Wrong code at -O1

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81555

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Thu Jul 27 09:43:01 2017
New Revision: 250616

URL: https://gcc.gnu.org/viewcvs?rev=250616&root=gcc&view=rev
Log:
        PR tree-optimization/81555
        PR tree-optimization/81556
        * tree-ssa-reassoc.c (rewrite_expr_tree): Add NEXT_CHANGED argument,
        if true, force CHANGED for the recursive invocation.
        (reassociate_bb): Remember original length of ops array, pass
        len != orig_len as NEXT_CHANGED in rewrite_expr_tree call.

        * gcc.c-torture/execute/pr81555.c: New test.
        * gcc.c-torture/execute/pr81556.c: New test.

Added:
    branches/gcc-5-branch/gcc/testsuite/gcc.c-torture/execute/pr81555.c
    branches/gcc-5-branch/gcc/testsuite/gcc.c-torture/execute/pr81556.c
Modified:
    branches/gcc-5-branch/gcc/ChangeLog
    branches/gcc-5-branch/gcc/testsuite/ChangeLog
    branches/gcc-5-branch/gcc/tree-ssa-reassoc.c