[turbofan] Disable LoadElimination completely for asm.js.

test/mjsunit/asm/load-elimination.js

Index: test/mjsunit/asm/load-elimination.js
diff --git a/test/mjsunit/asm/load-elimination.js b/test/mjsunit/asm/load-elimination.js
new file mode 100644
index 0000000000000000000000000000000000000000..cdc996222e6833b772b046f3ad0c13d35b6a0180
--- /dev/null
+++ b/test/mjsunit/asm/load-elimination.js
@@ -0,0 +1,26 @@
+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax
+
+var stdlib = this;
+var foreign = {};
+var heap = new ArrayBuffer(64 * 1024 * 1024);
+
+var foo = (function(stdlib, foreign, heap) {
+  "use asm";
+  var M16 = new Int16Array(heap);
+  var M32 = new Int32Array(heap);
+  function foo() {
+    M32[0] = 0x12341234;
+    var i = M32[0];
+    return M16[0];
+  }
+  return foo;
+})(stdlib, foreign, heap);
+
+assertEquals(0x1234, foo());
+assertEquals(0x1234, foo());
+%OptimizeFunctionOnNextCall(foo);
+assertEquals(0x1234, foo());