[Bug target/82618] Inefficient double-word subtration on x86_64

[uros at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82618

--- Comment #5 from uros at gcc dot gnu.org ---
Author: uros
Date: Thu Oct 19 17:35:39 2017
New Revision: 253905

URL: https://gcc.gnu.org/viewcvs?rev=253905&root=gcc&view=rev
Log:
        PR target/82618
        * config/i386/i386.md (sub to cmp): New peephole2 pattern.

testsuite/ChangeLog:

        PR target/82618
        * gcc.target/i386/pr82618.c: New test.


Added:
    trunk/gcc/testsuite/gcc.target/i386/pr82618.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/i386/i386.md
    trunk/gcc/testsuite/ChangeLog