[Bug target/70574] [5 Regression] wrong code with -mavx2, read of partially initialised stack variable

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70574

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Thu Jul  7 12:34:07 2016
New Revision: 238091

URL: https://gcc.gnu.org/viewcvs?rev=238091&root=gcc&view=rev
Log:
        Backported from mainline
        2016-04-08  Jakub Jelinek  <jakub@redhat.com>

        PR rtl-optimization/70574
        * fwprop.c (forward_propagate_and_simplify): Don't add
        REG_EQUAL note if DF_REF_REG (use) is a paradoxical subreg.
        (try_fwprop_subst): Don't add REG_EQUAL note if there are any
        paradoxical subregs within *loc.

        * gcc.target/i386/avx2-pr70574.c: New test.

Added:
    branches/gcc-5-branch/gcc/testsuite/gcc.target/i386/avx2-pr70574.c
Modified:
    branches/gcc-5-branch/gcc/ChangeLog
    branches/gcc-5-branch/gcc/fwprop.c
    branches/gcc-5-branch/gcc/testsuite/ChangeLog