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Add JSSpecialApiObjectType to fast path

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HTMLCollection and NodeList have InstanceType
JS_SPECIAL_API_OBJECT_TYPE, and therefore always run the slow case
of GetAlignedPropertyFromInternalField. This slows down the performance
of indexedPropertyGetter for both types, which are very commonly used
in websites.

Bug: 
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I36bd2cd7d9bbc19149e15174f6868b8a1f1658c8
Reviewed-on: https://chromium-review.googlesource.com/726529
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Adithya Srinivasan <adithyas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48760}
This commit is contained in:
Adithya Srinivasan 2017-10-18 14:57:27 -04:00 committed by Commit Bot
parent 789298d8ac
commit f65251be3c
2 changed files with 6 additions and 2 deletions
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7
include/v8.h
View File

@ -9116,6 +9116,7 @@ class Internals {
static const int kFirstNonstringType = 0x80;
static const int kOddballType = 0x83;
static const int kForeignType = 0x87;
static const int kJSSpecialApiObjectType = 0xbb;
static const int kJSApiObjectType = 0xbf;
static const int kJSObjectType = 0xc0;
@ -9723,7 +9724,8 @@ Local<Value> Object::GetInternalField(int index) {
// know where to find the internal fields and can return the value directly.
auto instance_type = I::GetInstanceType(obj);
if (instance_type == I::kJSObjectType ||
instance_type == I::kJSApiObjectType) {
instance_type == I::kJSApiObjectType ||
instance_type == I::kJSSpecialApiObjectType) {
int offset = I::kJSObjectHeaderSize + (internal::kApiPointerSize * index);
O* value = I::ReadField<O*>(obj, offset);
O** result = HandleScope::CreateHandle(reinterpret_cast<HO*>(obj), value);
@ -9743,7 +9745,8 @@ void* Object::GetAlignedPointerFromInternalField(int index) {
// know where to find the internal fields and can return the value directly.
auto instance_type = I::GetInstanceType(obj);
if (V8_LIKELY(instance_type == I::kJSObjectType ||
instance_type == I::kJSApiObjectType)) {
instance_type == I::kJSApiObjectType ||
instance_type == I::kJSSpecialApiObjectType)) {
int offset = I::kJSObjectHeaderSize + (internal::kApiPointerSize * index);
return I::ReadField<void*>(obj, offset);
}

1
src/objects.h
View File

@ -837,6 +837,7 @@ enum InstanceType : uint8_t {
STATIC_ASSERT(JS_OBJECT_TYPE == Internals::kJSObjectType);
STATIC_ASSERT(JS_API_OBJECT_TYPE == Internals::kJSApiObjectType);
STATIC_ASSERT(JS_SPECIAL_API_OBJECT_TYPE == Internals::kJSSpecialApiObjectType);
STATIC_ASSERT(FIRST_NONSTRING_TYPE == Internals::kFirstNonstringType);
STATIC_ASSERT(ODDBALL_TYPE == Internals::kOddballType);
STATIC_ASSERT(FOREIGN_TYPE == Internals::kForeignType);