Revert of Remove ExternalArray, derived types, and element kinds

src/elements-kind.cc

Index: src/elements-kind.cc
diff --git a/src/elements-kind.cc b/src/elements-kind.cc
index 0d29c3047238cbcfe6b0df71b196441686fa3e48..07d2837bdc86ca747d1e4468887f6bfa6b049dfd 100644
--- a/src/elements-kind.cc
+++ b/src/elements-kind.cc
@@ -15,17 +15,26 @@
 
 int ElementsKindToShiftSize(ElementsKind elements_kind) {
   switch (elements_kind) {
+    case EXTERNAL_INT8_ELEMENTS:
+    case EXTERNAL_UINT8_CLAMPED_ELEMENTS:
+    case EXTERNAL_UINT8_ELEMENTS:
     case UINT8_ELEMENTS:
     case INT8_ELEMENTS:
     case UINT8_CLAMPED_ELEMENTS:
       return 0;
+    case EXTERNAL_INT16_ELEMENTS:
+    case EXTERNAL_UINT16_ELEMENTS:
     case UINT16_ELEMENTS:
     case INT16_ELEMENTS:
       return 1;
+    case EXTERNAL_INT32_ELEMENTS:
+    case EXTERNAL_UINT32_ELEMENTS:
+    case EXTERNAL_FLOAT32_ELEMENTS:
     case UINT32_ELEMENTS:
     case INT32_ELEMENTS:
     case FLOAT32_ELEMENTS:
       return 2;
+    case EXTERNAL_FLOAT64_ELEMENTS:
     case FAST_DOUBLE_ELEMENTS:
     case FAST_HOLEY_DOUBLE_ELEMENTS:
     case FLOAT64_ELEMENTS:
@@ -44,10 +53,16 @@
 }
 
 
+static bool IsTypedArrayElementsKind(ElementsKind elements_kind) {
+  return IsFixedTypedArrayElementsKind(elements_kind) ||
+         IsExternalArrayElementsKind(elements_kind);
+}
+
+
 int GetDefaultHeaderSizeForElementsKind(ElementsKind elements_kind) {
   STATIC_ASSERT(FixedArray::kHeaderSize == FixedDoubleArray::kHeaderSize);
 
-  if (IsFixedTypedArrayElementsKind(elements_kind)) {
+  if (IsTypedArrayElementsKind(elements_kind)) {
     return 0;
   } else {
     return FixedArray::kHeaderSize - kHeapObjectTag;
@@ -110,8 +125,17 @@
 
 
 ElementsKind GetNextTransitionElementsKind(ElementsKind kind) {
-  int index = GetSequenceIndexFromFastElementsKind(kind);
-  return GetFastElementsKindFromSequenceIndex(index + 1);
+  switch (kind) {
+#define FIXED_TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
+    case TYPE##_ELEMENTS: return EXTERNAL_##TYPE##_ELEMENTS;
+
+    TYPED_ARRAYS(FIXED_TYPED_ARRAY_CASE)
+#undef FIXED_TYPED_ARRAY_CASE
+    default: {
+      int index = GetSequenceIndexFromFastElementsKind(kind);
+      return GetFastElementsKindFromSequenceIndex(index + 1);
+    }
+  }
 }
 
 
@@ -122,9 +146,18 @@
 
 bool IsMoreGeneralElementsKindTransition(ElementsKind from_kind,
                                          ElementsKind to_kind) {
-  if (IsFixedTypedArrayElementsKind(from_kind) ||
-      IsFixedTypedArrayElementsKind(to_kind)) {
-    return false;
+  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;
+    }
   }
   if (IsFastElementsKind(from_kind) && IsFastTransitionTarget(to_kind)) {
     switch (from_kind) {