[Bug tree-optimization/63379] [4.8 Regression] Incorrect vectorization when enabling SSE and O3, initialises loop with wrong value

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63379

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Fri Oct 10 14:23:35 2014
New Revision: 216086

URL: https://gcc.gnu.org/viewcvs?rev=216086&root=gcc&view=rev
Log:
2014-10-10  Richard Biener  <rguenther@suse.de>

    PR tree-optimization/63379
    * tree-vect-slp.c (vect_get_constant_vectors): Do not compute
    a neutral operand for min/max when it is not a reduction chain.

    * gcc.dg/vect/pr63379.c: New testcase.

Added:
    branches/gcc-4_9-branch/gcc/testsuite/gcc.dg/vect/pr63379.c
Modified:
    branches/gcc-4_9-branch/gcc/ChangeLog
    branches/gcc-4_9-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_9-branch/gcc/tree-vect-slp.c