[Bug target/81504] [7/8 Regression] gcc-7 regression: vec_st in loop misoptimized

[wschmidt at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81504

--- Comment #10 from Bill Schmidt <wschmidt at gcc dot gnu.org> ---
Author: wschmidt
Date: Thu Aug 31 20:28:17 2017
New Revision: 251575

URL: https://gcc.gnu.org/viewcvs?rev=251575&root=gcc&view=rev
Log:
2017-08-31  Bill Schmidt  <wschm...@linux.vnet.ibm.com>

        Backport from mainline
        2017-08-25  Bill Schmidt  <wschm...@linux.vnet.ibm.com>

        PR target/81504
        * config/rs6000/rs6000.c (find_alignment_op): Add reference
        parameter and_insn and return it.
        (recombine_lvx_pattern): Insert a copy to ensure availability of
        the base register of the copied masking operation at the point of
        the instruction replacement.
        (recombine_stvx_pattern): Likewise.


Modified:
    branches/gcc-7-branch/gcc/ChangeLog
    branches/gcc-7-branch/gcc/config/rs6000/rs6000.c