Subject: gc ppc64le force AO load

From: Michel Normand <normand@linux.vnet.ibm.com>

Force AO_load() to map to AO_load_acquire() for powerpc.  The

AO_load_acquire() function includes isync instructions that

are critical for proper behavior on power system.

Signed-Off-By: Will Schmidt <will_schmidt at vnet.ibm.com>

Signed-off-by: Michel Normand <normand@linux.vnet.ibm.com>

diff -up libatomic_ops-7.4.4/src/atomic_ops/sysdeps/gcc/powerpc.h.gc_ppc64le_force_AO_load libatomic_ops-7.4.4/src/atomic_ops/sysdeps/gcc/powerpc.h

--- libatomic_ops-7.4.4/src/atomic_ops/sysdeps/gcc/powerpc.h.gc_ppc64le_force_AO_load	2016-05-24 15:01:55.000000000 -0500

+++ libatomic_ops-7.4.4/src/atomic_ops/sysdeps/gcc/powerpc.h	2016-06-17 10:27:10.503593018 -0500

@@ -29,6 +29,8 @@

 #include "../all_aligned_atomic_load_store.h"

+#define AO_load(addr) AO_load_acquire(addr)

+

 #include "../test_and_set_t_is_ao_t.h"

         /* There seems to be no byte equivalent of lwarx, so this       */

         /* may really be what we want, at least in the 32-bit case.     */