Changeset 295036 in webkit for trunk/Source/JavaScriptCore/heap/Strong.h

Timestamp:

May 30, 2022, 4:41:10 PM (3 years ago)

Author:

[email protected]

Message:

[JSC] Make Strong::set cheap
​https://bugs.webkit.org/show_bug.cgi?id=241090

Reviewed by Mark Lam.

HandleSet::writeBarrier is frequently called because it is called every time we set a value in Strong<>.
This patch optimizes it,

1. We should make it inline function since it has a super fast path major use can be covered. And this function is small.
2. We should not always remove a node from the list first. We should insert / remove it only when necessary.
3. Remove m_immediateList since it is not necessary.
4. Make HandleNode as a derived class of BasicRawSentinelNode to make implementation simpler.

This change improves promise benchmarks score since promise uses microtasks which hold values via Strong<>.

ToT
Time(doxbee-async-bluebird): 42.8 ms.
Time(doxbee-async-es2017-babel): 36.4 ms.
Time(doxbee-async-es2017-native): 28.3 ms.
Time(doxbee-promises-bluebird): 514.2 ms.
Time(doxbee-promises-es2015-native): 44.8 ms.
Time(fibonacci-async-es2017-babel): 380.5 ms.
Time(fibonacci-async-es2017-native): 218.2 ms.
Time(parallel-async-bluebird): 648.8 ms.
Time(parallel-async-es2017-babel): 116.9 ms.
Time(parallel-async-es2017-native): 115.6 ms.
Time(parallel-promises-bluebird): 638 ms.
Time(parallel-promises-es2015-native): 82 ms.

Patched
Time(doxbee-async-bluebird): 38 ms.
Time(doxbee-async-es2017-babel): 27 ms.
Time(doxbee-async-es2017-native): 19.5 ms.
Time(doxbee-promises-bluebird): 508.3 ms.
Time(doxbee-promises-es2015-native): 33.3 ms.
Time(fibonacci-async-es2017-babel): 349.1 ms.
Time(fibonacci-async-es2017-native): 151 ms.
Time(parallel-async-bluebird): 639.6 ms.
Time(parallel-async-es2017-babel): 100.9 ms.
Time(parallel-async-es2017-native): 101.9 ms.
Time(parallel-promises-bluebird): 614 ms.
Time(parallel-promises-es2015-native): 70.9 ms.

• Source/JavaScriptCore/heap/HandleSet.cpp:

(JSC::HandleSet::writeBarrier): Deleted.

• Source/JavaScriptCore/heap/HandleSet.h:

(JSC::HandleSet::heapFor):
(JSC::HandleSet::allocate):
(JSC::HandleSet::deallocate):
(JSC::HandleSet::writeBarrier):
(JSC::HandleSet::toHandle): Deleted.
(JSC::HandleSet::toNode): Deleted.
(JSC::HandleNode::HandleNode): Deleted.
(JSC::HandleNode::setPrev): Deleted.
(JSC::HandleNode::prev): Deleted.
(JSC::HandleNode::setNext): Deleted.
(JSC::HandleNode::next): Deleted.

• Source/JavaScriptCore/heap/Strong.h:

(JSC::Strong::set):

Canonical link: ​https://commits.webkit.org/251131@main

File:

• trunk/Source/JavaScriptCore/heap/Strong.h (modified) (1 diff)

trunk/Source/JavaScriptCore/heap/Strong.h

@@ -142 +142 @@
         ASSERT(slot());
         JSValue value = HandleTypes<T>::toJSValue(externalType);
-        HandleSet::heapFor(slot())->writeBarrier(slot(), value);
+        HandleSet::heapFor(slot())->template writeBarrier<std::is_base_of_v<JSCell, T>>(slot(), value);
         *slot() = value;
     }