[Bug tree-optimization/79920] Incorrect floating point results when compiling with -O3

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79920

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Wed Mar  8 08:50:01 2017
New Revision: 245968

URL: https://gcc.gnu.org/viewcvs?rev=245968&root=gcc&view=rev
Log:
2017-03-08  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/79920
        * tree-vect-slp.c (vect_create_mask_and_perm): Remove and inline
        with ncopies == 1 to ...
        (vect_transform_slp_perm_load): ... here.  Properly compute
        all element loads by iterating VF times over the group.  Do
        not handle ncopies (computed in a broken way) in
        vect_create_mask_and_perm.

        * gcc.dg/vect/pr79920.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/vect/pr79920.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-vect-slp.c