Reland of "Remove ExternalArray, derived types, and element kinds"

src/runtime/runtime-typedarray.cc

 // 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.
 
 #include "src/v8.h"
 
 #include "src/arguments.h"
 #include "src/messages.h"
 #include "src/runtime/runtime.h"
 #include "src/runtime/runtime-utils.h"
@@ skipping 141 matching lines @@
   array_buffer->set_is_external(true);
   Runtime::NeuterArrayBuffer(array_buffer);
   isolate->heap()->UnregisterArrayBuffer(
       isolate->heap()->InNewSpace(*array_buffer), backing_store);
   isolate->array_buffer_allocator()->Free(backing_store, byte_length);
   return isolate->heap()->undefined_value();
 }
 
 
 void Runtime::ArrayIdToTypeAndSize(int arrayId, ExternalArrayType* array_type,
-                                   ElementsKind* external_elements_kind,
                                    ElementsKind* fixed_elements_kind,
                                    size_t* element_size) {
   switch (arrayId) {
 #define ARRAY_ID_CASE(Type, type, TYPE, ctype, size)      \
   case ARRAY_ID_##TYPE:                                   \
     *array_type = kExternal##Type##Array;                 \
-    *external_elements_kind = EXTERNAL_##TYPE##_ELEMENTS; \
     *fixed_elements_kind = TYPE##_ELEMENTS;               \
     *element_size = size;                                 \
     break;
 
     TYPED_ARRAYS(ARRAY_ID_CASE)
 #undef ARRAY_ID_CASE
 
     default:
       UNREACHABLE();
   }
 }
 
 
 RUNTIME_FUNCTION(Runtime_TypedArrayInitialize) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 6);
   CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, holder, 0);
   CONVERT_SMI_ARG_CHECKED(arrayId, 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, maybe_buffer, 2);
   CONVERT_NUMBER_ARG_HANDLE_CHECKED(byte_offset_object, 3);
   CONVERT_NUMBER_ARG_HANDLE_CHECKED(byte_length_object, 4);
   CONVERT_BOOLEAN_ARG_CHECKED(initialize, 5);
 
   RUNTIME_ASSERT(arrayId >= Runtime::ARRAY_ID_FIRST &&
                  arrayId <= Runtime::ARRAY_ID_LAST);
 
   ExternalArrayType array_type = kExternalInt8Array;  // Bogus initialization.
   size_t element_size = 1;                            // Bogus initialization.
-  ElementsKind external_elements_kind =
-      EXTERNAL_INT8_ELEMENTS;                        // Bogus initialization.
   ElementsKind fixed_elements_kind = INT8_ELEMENTS;  // Bogus initialization.
-  Runtime::ArrayIdToTypeAndSize(arrayId, &array_type, &external_elements_kind,
-                                &fixed_elements_kind, &element_size);
+  Runtime::ArrayIdToTypeAndSize(arrayId, &array_type, &fixed_elements_kind,
+                                &element_size);
   RUNTIME_ASSERT(holder->map()->elements_kind() == fixed_elements_kind);
 
   size_t byte_offset = 0;
   size_t byte_length = 0;
   RUNTIME_ASSERT(TryNumberToSize(isolate, *byte_offset_object, &byte_offset));
   RUNTIME_ASSERT(TryNumberToSize(isolate, *byte_length_object, &byte_length));
 
   if (maybe_buffer->IsJSArrayBuffer()) {
     Handle<JSArrayBuffer> buffer = Handle<JSArrayBuffer>::cast(maybe_buffer);
     size_t array_buffer_byte_length =
@@ skipping 21 matching lines @@
   }
   Handle<Object> length_obj = isolate->factory()->NewNumberFromSize(length);
   holder->set_length(*length_obj);
   holder->set_byte_offset(*byte_offset_object);
   holder->set_byte_length(*byte_length_object);
 
   if (!maybe_buffer->IsNull()) {
     Handle<JSArrayBuffer> buffer = Handle<JSArrayBuffer>::cast(maybe_buffer);
     holder->set_buffer(*buffer);
 
-    Handle<ExternalArray> elements = isolate->factory()->NewExternalArray(
-        static_cast<int>(length), array_type,
-        static_cast<uint8_t*>(buffer->backing_store()) + byte_offset);
-    Handle<Map> map =
-        JSObject::GetElementsTransitionMap(holder, external_elements_kind);
-    JSObject::SetMapAndElements(holder, map, elements);
-    DCHECK(IsExternalArrayElementsKind(holder->map()->elements_kind()));
+    Handle<FixedTypedArrayBase> elements =
+        isolate->factory()->NewFixedTypedArrayWithExternalPointer(
+            static_cast<int>(length), array_type,
+            static_cast<uint8_t*>(buffer->backing_store()) + byte_offset);
+    holder->set_elements(*elements);
   } else {
     Handle<JSArrayBuffer> buffer = isolate->factory()->NewJSArrayBuffer();
     Runtime::SetupArrayBuffer(isolate, buffer, true, NULL, byte_length,
                               SharedFlag::kNotShared);
     holder->set_buffer(*buffer);
     Handle<FixedTypedArrayBase> elements =
         isolate->factory()->NewFixedTypedArray(static_cast<int>(length),
                                                array_type, initialize);
     holder->set_elements(*elements);
   }
@@ skipping 12 matching lines @@
   CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, holder, 0);
   CONVERT_SMI_ARG_CHECKED(arrayId, 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, source, 2);
   CONVERT_NUMBER_ARG_HANDLE_CHECKED(length_obj, 3);
 
   RUNTIME_ASSERT(arrayId >= Runtime::ARRAY_ID_FIRST &&
                  arrayId <= Runtime::ARRAY_ID_LAST);
 
   ExternalArrayType array_type = kExternalInt8Array;  // Bogus initialization.
   size_t element_size = 1;                            // Bogus initialization.
-  ElementsKind external_elements_kind =
-      EXTERNAL_INT8_ELEMENTS;                        // Bogus intialization.
   ElementsKind fixed_elements_kind = INT8_ELEMENTS;  // Bogus initialization.
-  Runtime::ArrayIdToTypeAndSize(arrayId, &array_type, &external_elements_kind,
-                                &fixed_elements_kind, &element_size);
+  Runtime::ArrayIdToTypeAndSize(arrayId, &array_type, &fixed_elements_kind,
+                                &element_size);
 
   RUNTIME_ASSERT(holder->map()->elements_kind() == fixed_elements_kind);
 
   Handle<JSArrayBuffer> buffer = isolate->factory()->NewJSArrayBuffer();
   size_t length = 0;
   if (source->IsJSTypedArray() &&
       JSTypedArray::cast(*source)->type() == array_type) {
     length_obj = handle(JSTypedArray::cast(*source)->length(), isolate);
     length = JSTypedArray::cast(*source)->length_value();
   } else {
@@ skipping 35 matching lines @@
         isolate, NewRangeError(MessageTemplate::kInvalidArrayBufferLength));
   }
 
   holder->set_buffer(*buffer);
   holder->set_byte_offset(Smi::FromInt(0));
   Handle<Object> byte_length_obj(
       isolate->factory()->NewNumberFromSize(byte_length));
   holder->set_byte_length(*byte_length_obj);
   holder->set_length(*length_obj);
 
-  Handle<ExternalArray> elements = isolate->factory()->NewExternalArray(
-      static_cast<int>(length), array_type,
-      static_cast<uint8_t*>(buffer->backing_store()));
-  Handle<Map> map =
-      JSObject::GetElementsTransitionMap(holder, external_elements_kind);
-  JSObject::SetMapAndElements(holder, map, elements);
+  Handle<FixedTypedArrayBase> elements =
+      isolate->factory()->NewFixedTypedArrayWithExternalPointer(
+          static_cast<int>(length), array_type,
+          static_cast<uint8_t*>(buffer->backing_store()));
+  holder->set_elements(*elements);
 
   if (source->IsJSTypedArray()) {
     Handle<JSTypedArray> typed_array(JSTypedArray::cast(*source));
 
     if (typed_array->type() == holder->type()) {
       uint8_t* backing_store =
           static_cast<uint8_t*>(typed_array->GetBuffer()->backing_store());
       size_t source_byte_offset =
           NumberToSize(isolate, typed_array->byte_offset());
       memcpy(buffer->backing_store(), backing_store + source_byte_offset,
@@ skipping 390 matching lines @@
 DATA_VIEW_SETTER(Uint16, uint16_t)
 DATA_VIEW_SETTER(Int16, int16_t)
 DATA_VIEW_SETTER(Uint32, uint32_t)
 DATA_VIEW_SETTER(Int32, int32_t)
 DATA_VIEW_SETTER(Float32, float)
 DATA_VIEW_SETTER(Float64, double)
 
 #undef DATA_VIEW_SETTER
 }  // namespace internal
 }  // namespace v8