[Bug tree-optimization/67800] [6 Regression] Missed vectorization opportunity on x86 (DOT_PROD_EXPR in non-reduction)

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67800

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Thu Dec  3 08:43:22 2015
New Revision: 231221

URL: https://gcc.gnu.org/viewcvs?rev=231221&root=gcc&view=rev
Log:
2015-12-03  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/67800
        PR tree-optimization/68333
        * tree-vect-patterns.c (vect_recog_dot_prod_pattern): Restore
        restriction to reduction contexts but allow SLP reductions as well.
        (vect_recog_sad_pattern): Likewise.
        (vect_recog_widen_sum_pattern): Likewise.

        * gcc.target/i386/vect-pr67800.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.target/i386/vect-pr67800.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-vect-patterns.c