[PATCH, RTL-optimization]: Optimize need_atomic_barrier_p a bit

[Uros Bizjak]

Hello!

We can use MEMMODEL_BASE_MASK here to avoid a couple of similar cases.

2015-06-11  Uros Bizjak  <ubiz...@gmail.com>

    * emit-rtl.c (need_atomic_barrier_p): Mask model with
    MEMMODEL_BASE_MASK.  Remove MEMMODEL_SYNC_* cases.

Tested on x86_64-linux-gnu {,-m32}.

OK for mainline?

Uros.

Index: emit-rtl.c
===================================================================
--- emit-rtl.c  (revision 224363)
+++ emit-rtl.c  (working copy)
@@ -6315,20 +6315,17 @@ insn_location (const rtx_insn *insn)
 bool
 need_atomic_barrier_p (enum memmodel model, bool pre)
 {
-  switch (model & MEMMODEL_MASK)
+  switch (model & MEMMODEL_BASE_MASK)
     {
     case MEMMODEL_RELAXED:
     case MEMMODEL_CONSUME:
       return false;
     case MEMMODEL_RELEASE:
-    case MEMMODEL_SYNC_RELEASE:
       return pre;
     case MEMMODEL_ACQUIRE:
-    case MEMMODEL_SYNC_ACQUIRE:
       return !pre;
     case MEMMODEL_ACQ_REL:
     case MEMMODEL_SEQ_CST:
-    case MEMMODEL_SYNC_SEQ_CST:
       return true;
     default:
       gcc_unreachable ();