[Bug tree-optimization/98117] [8/9/10/11 Regression] wrong code with "-O3 -fno-tree-scev-cprop" since r8-1163-g7078979b291419f3

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98117

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:cdcbef3c3310a14f2994982b44cb1f8e14c77232

commit r11-5820-gcdcbef3c3310a14f2994982b44cb1f8e14c77232
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Dec 7 10:29:07 2020 +0100

    tree-optimization/98117 - fix range set by vectorization on niter IVs

    This avoids the degenerate case of a TYPE_MAX_VALUE latch iteration
    count value causing wrong range info for the vector IV.  There's
    still the case of VF == 1 where if we don't know whether we hit the
    above case we cannot emit a range.

    2020-12-07  Richard Biener  <rguenther@suse.de>

            PR tree-optimization/98117
            * tree-vect-loop-manip.c (vect_gen_vector_loop_niters):
            Properly handle degenerate niter when setting the vector
            loop IV range.

            * gcc.dg/torture/pr98117.c: New testcase.