[Bug target/70465] [5/6 Regression] Poor code for x87 asm

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70465

--- Comment #21 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Wed Feb 22 17:17:17 2017
New Revision: 245654

URL: https://gcc.gnu.org/viewcvs?rev=245654&root=gcc&view=rev
Log:
        PR target/70465
        * reg-stack.c (emit_swap_insn): Treat (float_extend:?F (mem:?F))
        and (const_double:?F) like (mem:?F) for the purpose of fxch %st(1)
        elimination by swapping fld*.

        * gcc.target/i386/pr70465-2.c: New test.

Added:
    trunk/gcc/testsuite/gcc.target/i386/pr70465-2.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/reg-stack.c
    trunk/gcc/testsuite/ChangeLog