[Bug tree-optimization/92351] [10 Regression] Wrong code with -O3 -match=skylake since r277569

[avieira at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92351

--- Comment #3 from avieira at gcc dot gnu.org ---
Author: avieira
Date: Fri Nov  8 13:52:56 2019
New Revision: 277974

URL: https://gcc.gnu.org/viewcvs?rev=277974&root=gcc&view=rev
Log:
[vect] PR 92351: When peeling for alignment make alignment of epilogues unknown

gcc/ChangeLog:
2019-11-08  Andre Vieira  <andre.simoesdiasvie...@arm.com>

        PR tree-optimization/92351
        * tree-vect-data-refs.c (vect_compute_data_ref_alignment): When we are
        peeling the main loop for alignment, make sure to set the misalignment
        of the epilogue's data references to DR_MISALIGNMENT_UNKNOWN.

gcc/testsuite/ChangeLog:
2019-11-08  Andre Vieira  <andre.simoesdiasvie...@arm.com>

        PR tree-optimization/92351
        * gcc.dg/vect/vect-peel-2.c: Disable epilogue vectorization and
        split the source of this test to...
        * gcc.dg/vect/vect-peel-2-src.c: ... This.
        * gcc.dg/vect/vect-peel-2-epilogues.c: New test.

Added:
    trunk/gcc/testsuite/gcc.dg/vect/vect-peel-2-epilogues.c
    trunk/gcc/testsuite/gcc.dg/vect/vect-peel-2-src.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/vect/vect-peel-2.c
    trunk/gcc/tree-vect-data-refs.c