[Bug middle-end/55492] __atomic_load doesn't match ACQUIRE memory model

[yvan.roux at linaro dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55492



--- Comment #8 from Yvan Roux <yvan.roux at linaro dot org> 2012-12-14 10:14:15 
UTC ---

Hi Richard,



Thanks for having applied and cleaned my patch.



Regarding this cleanup, if we want to be consistant I think we have to remove

the memory model test in expand_atomic_store (see the peace of patch below) as

the atomic_store valid memory model variants are RELAXED, SEQ_CST, and RELEASE

and that expand_mem_thread_fence doesn't emit any barrier in the RELEASE model

case.



Thanks,

Yvan



@@ -7537,8 +7537,7 @@ expand_atomic_store (rtx mem, rtx val, enum memmodel

model, bool use_release)

     }



   /* Otherwise assume stores are atomic, and emit the proper barriers.  */

-  if (model == MEMMODEL_SEQ_CST || model == MEMMODEL_RELEASE)

-    expand_mem_thread_fence (model);

+  expand_mem_thread_fence (model);



   emit_move_insn (mem, val);