[Bug target/69548] libatomic fails to build with -Os on powerpc64-linux

[amodra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69548

--- Comment #2 from Alan Modra <amodra at gcc dot gnu.org> ---
Author: amodra
Date: Tue Feb  2 01:29:17 2016
New Revision: 233065

URL: https://gcc.gnu.org/viewcvs?rev=233065&root=gcc&view=rev
Log:
[RS6000] lqarx and stqcx. registers

lqarx RT and stqcx. RS are valid only with even numbered gprs.  The
predicate to enforce this happens to allow a loophole, closed by this
patch.

        PR target/69548
gcc/
        * config/rs6000/predicates.md (quad_int_reg_operand): Don't
        allow subregs.
gcc/testsuite/
        * gcc.target/powerpc/pr69548.c: New test.


Added:
    trunk/gcc/testsuite/gcc.target/powerpc/pr69548.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/rs6000/predicates.md
    trunk/gcc/testsuite/ChangeLog