[Atomics] code stubs for atomic operations

test/cctest/test-disasm-arm.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 985 matching lines @@
             "e16dc7ff       strd ip, [sp, #-127]!");
 
     COMPARE(pld(MemOperand(r1, 0)),
             "f5d1f000       pld [r1]");
     COMPARE(pld(MemOperand(r2, 128)),
             "f5d2f080       pld [r2, #+128]");
   }
 
   VERIFY_RUN();
 }
+
+
+TEST(Barrier) {
+  SET_UP();
+
+  if (CpuFeatures::IsSupported(ARMv7)) {
+    CpuFeatureScope scope(&assm, ARMv7);
+
+    COMPARE(dmb(OSHLD),
+            "f57ff051       dmb oshld");
+    COMPARE(dmb(OSHST),
+            "f57ff052       dmb oshst");
+    COMPARE(dmb(OSH),
+            "f57ff053       dmb osh");
+    COMPARE(dmb(NSHLD),
+            "f57ff055       dmb nshld");
+    COMPARE(dmb(NSHST),
+            "f57ff056       dmb nshst");
+    COMPARE(dmb(NSH),
+            "f57ff057       dmb nsh");
+    COMPARE(dmb(ISHLD),
+            "f57ff059       dmb ishld");
+    COMPARE(dmb(ISHST),
+            "f57ff05a       dmb ishst");
+    COMPARE(dmb(ISH),
+            "f57ff05b       dmb ish");
+    COMPARE(dmb(LD),
+            "f57ff05d       dmb ld");
+    COMPARE(dmb(ST),
+            "f57ff05e       dmb st");
+    COMPARE(dmb(SY),
+            "f57ff05f       dmb sy");
+
+    COMPARE(dsb(ISH),
+            "f57ff04b       dsb ish");
+
+    COMPARE(isb(ISH),
+            "f57ff06b       isb ish");
+  }
+
+  VERIFY_RUN();
+}