AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

ArrayUnshift builtin handlified.

Browse Source 
R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/206463002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20143 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
ishell@chromium.org 2014-03-21 08:12:16 +00:00
parent 586f64e1f3
commit 863b5d30cd
1 changed files with 20 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

45
src/builtins.cc
View File

@ -625,24 +625,24 @@ BUILTIN(ArrayShift) {
BUILTIN(ArrayUnshift) {
HandleScope scope(isolate);
Heap* heap = isolate->heap();
Object* receiver = *args.receiver();
FixedArrayBase* elms_obj;
MaybeObject* maybe_elms_obj =
EnsureJSArrayWithWritableFastElements(heap, receiver, NULL, 0);
if (maybe_elms_obj == NULL)
return CallJsBuiltin(isolate, "ArrayUnshift", args);
if (!maybe_elms_obj->To(&elms_obj)) return maybe_elms_obj;
if (!IsJSArrayFastElementMovingAllowed(heap, JSArray::cast(receiver))) {
Handle<Object> receiver = args.receiver();
Handle<Object> elms_or_null =
EnsureJSArrayWithWritableFastElementsWrapper(isolate, receiver, NULL, 0);
RETURN_IF_EMPTY_HANDLE(isolate, elms_or_null);
if ((*elms_or_null == NULL) ||
!IsJSArrayFastElementMovingAllowed(heap,
*Handle<JSArray>::cast(receiver))) {
return CallJsBuiltin(isolate, "ArrayUnshift", args);
}
JSArray* array = JSArray::cast(receiver);
Handle<FixedArrayBase> elms_obj = Handle<FixedArrayBase>::cast(elms_or_null);
Handle<JSArray> array = Handle<JSArray>::cast(receiver);
ASSERT(!array->map()->is_observed());
if (!array->HasFastSmiOrObjectElements()) {
return CallJsBuiltin(isolate, "ArrayUnshift", args);
}
FixedArray* elms = FixedArray::cast(elms_obj);
Handle<FixedArray> elms = Handle<FixedArray>::cast(elms_obj);
int len = Smi::cast(array->length())->value();
int to_add = args.length() - 1;
@ -651,31 +651,26 @@ BUILTIN(ArrayUnshift) {
// we should never hit this case.
ASSERT(to_add <= (Smi::kMaxValue - len));
MaybeObject* maybe_object =
array->EnsureCanContainElements(&args, 1, to_add,
DONT_ALLOW_DOUBLE_ELEMENTS);
if (maybe_object->IsFailure()) return maybe_object;
JSObject::EnsureCanContainElements(array, &args, 1, to_add,
DONT_ALLOW_DOUBLE_ELEMENTS);
if (new_length > elms->length()) {
// New backing storage is needed.
int capacity = new_length + (new_length >> 1) + 16;
FixedArray* new_elms;
MaybeObject* maybe_elms = heap->AllocateUninitializedFixedArray(capacity);
if (!maybe_elms->To(&new_elms)) return maybe_elms;
Handle<FixedArray> new_elms =
isolate->factory()->NewUninitializedFixedArray(capacity);
ElementsKind kind = array->GetElementsKind();
ElementsAccessor* accessor = array->GetElementsAccessor();
MaybeObject* maybe_failure = accessor->CopyElements(
NULL, 0, kind, new_elms, to_add,
ElementsAccessor::kCopyToEndAndInitializeToHole, elms);
ASSERT(!maybe_failure->IsFailure());
USE(maybe_failure);
accessor->CopyElements(
Handle<JSObject>::null(), 0, kind, new_elms, to_add,
ElementsAccessor::kCopyToEndAndInitializeToHole, elms);
elms = new_elms;
array->set_elements(elms);
array->set_elements(*elms);
} else {
DisallowHeapAllocation no_gc;
heap->MoveElements(elms, to_add, 0, len);
heap->MoveElements(*elms, to_add, 0, len);
}
// Add the provided values.