[Bug tree-optimization/85284] [7 Regression] Loop miscompilation starting with r238367

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85284

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Mon Apr  9 13:27:33 2018
New Revision: 259234

URL: https://gcc.gnu.org/viewcvs?rev=259234&root=gcc&view=rev
Log:
2018-04-09  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/85284
        * tree-ssa-loop-niter.c (number_of_iterations_exit_assumptions):
        Only use the niter constraining form of simple_iv when the exit
        is always executed.

        * gcc.dg/torture/pr85284.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/torture/pr85284.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-loop-niter.c