Support typed arrays in IsMoreGeneralElementsKindTransition.

R=verwaest@chromium.org
BUG=357054
LOG=Y

Review URL: https://codereview.chromium.org/220403004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20410 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/elements-kind.cc

@@ -172,8 +172,27 @@ ElementsKind GetNextMoreGeneralFastElementsKind(ElementsKind elements_kind,
 }
 
 
+static bool IsTypedArrayElementsKind(ElementsKind elements_kind) {
+  return IsFixedTypedArrayElementsKind(elements_kind) ||
+      IsExternalArrayElementsKind(elements_kind);
+}
+
+
 bool IsMoreGeneralElementsKindTransition(ElementsKind from_kind,
                                          ElementsKind to_kind) {
+  if (IsTypedArrayElementsKind(from_kind) ||
+      IsTypedArrayElementsKind(to_kind)) {
+    switch (from_kind) {
+#define FIXED_TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
+      case TYPE##_ELEMENTS:                                   \
+        return to_kind == EXTERNAL_##TYPE##_ELEMENTS;
+
+      TYPED_ARRAYS(FIXED_TYPED_ARRAY_CASE);
+#undef FIXED_TYPED_ARRAY_CASE
+      default:
+        return false;
+    }
+  }
   switch (from_kind) {
     case FAST_SMI_ELEMENTS:
       return to_kind != FAST_SMI_ELEMENTS;

test/mjsunit/regress/regress-357054.js

+// Copyright 2014 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.
+
+[].__defineSetter__(0, function() { });
+function f(a,i,v) { a[i] = v; }
+a = [0,0,0];
+f(a,0,5);
+a = new Float32Array(5);
+f(a,2,5.5);