[Bug tree-optimization/68529] scev failed for while(i--)

["amker at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68529

--- Comment #7 from amker at gcc dot gnu.org ---
Author: amker
Date: Tue Dec  1 05:22:16 2015
New Revision: 231097

URL: https://gcc.gnu.org/viewcvs?rev=231097&root=gcc&view=rev
Log:

        PR tree-optimization/68529
        * tree-ssa-loop-niter.c (number_of_iterations_ne): Add new param.
        Compute no-overflow information for control iv.
        (number_of_iterations_lt, number_of_iterations_le): Add new param.
        (number_of_iterations_cond): Pass new argument to above functions.

        PR tree-optimization/68529
        * gcc.dg/tree-ssa/pr68529-1.c: New test.
        * gcc.dg/tree-ssa/pr68529-2.c: New test.
        * gcc.dg/tree-ssa/pr68529-3.c: New test.


Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr68529-1.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr68529-2.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr68529-3.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-loop-niter.c