[Bug target/70821] x86_64: __atomic_fetch_add/sub() uses XADD rather than DECL in some cases

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70821

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Thu Apr 28 17:10:14 2016
New Revision: 235586

URL: https://gcc.gnu.org/viewcvs?rev=235586&root=gcc&view=rev
Log:
        PR target/70821
        * config/i386/sync.md (define_peephole2 *atomic_fetch_add_cmp<mode>):
        Add new peephole2 where the first insn is *mov<mode>_or instead of
        *mov<mode>_internal.

        * gcc.target/i386/pr70821.c: New test.

Added:
    trunk/gcc/testsuite/gcc.target/i386/pr70821.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/i386/sync.md
    trunk/gcc/testsuite/ChangeLog