[Bug target/59054] Powerpc -O0 -mcpu=power7 generates sub-optimal code to load 0

[meissner at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59054

--- Comment #3 from Michael Meissner <meissner at gcc dot gnu.org> ---
Author: meissner
Date: Tue Nov 12 20:55:58 2013
New Revision: 204718

URL: http://gcc.gnu.org/viewcvs?rev=204718&root=gcc&view=rev
Log:
2013-11-12  Michael Meissner  <meiss...@linux.vnet.ibm.com>

    PR target/59054
    * config/rs6000/rs6000.md (movdi_internal32): Eliminate
    constraints that would allow DImode into the traditional Altivec
    registers, but cause undesirable code generation when loading 0 as
    a constant.
    (movdi_internal64): Likewise.
    (cmp<mode>_fpr): Do not use %x for CR register output.
    (extendsfdf2_fpr): Fix constraints when -mallow-upper-df and
    -mallow-upper-sf debug switches are used.

[gcc/testsuite]
2013-11-12  Michael Meissner  <meiss...@linux.vnet.ibm.com>

    PR target/59054
    * gcc.target/powerpc/pr59054.c: New test.


Added:
    trunk/gcc/testsuite/gcc.target/powerpc/pr59054.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/rs6000/rs6000.md
    trunk/gcc/testsuite/ChangeLog