Changeset 255542 in webkit for trunk/Source/JavaScriptCore/bytecode/CodeBlock.cpp

Timestamp:

Jan 31, 2020, 10:18:18 PM (6 years ago)

Author:

[email protected]

Message:

[JSC] Hold StructureID instead of Structure* in PolyProtoAccessChain and DFG::CommonData
​https://bugs.webkit.org/show_bug.cgi?id=207086

Reviewed by Mark Lam.

PolyProtoAccessChain and DFG::CommonData are kept alive so long as associated AccessCase / DFG/FTL CodeBlock
is alive. They hold Vector<Structure*> / Vector<WriteBarrier<Structure*>>, but access frequency is low. And
We should hold Vector<StructureID> instead to cut 50% of the size.

• bytecode/AccessCase.cpp:

(JSC::AccessCase::commit):
(JSC::AccessCase::forEachDependentCell const):
(JSC::AccessCase::doesCalls const):
(JSC::AccessCase::visitWeak const):
(JSC::AccessCase::propagateTransitions const):
(JSC::AccessCase::generateWithGuard):

• bytecode/AccessCase.h:
• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::propagateTransitions):
(JSC::CodeBlock::determineLiveness):
(JSC::CodeBlock::stronglyVisitWeakReferences):

• bytecode/GetByStatus.cpp:

(JSC::GetByStatus::computeForStubInfoWithoutExitSiteFeedback):

• bytecode/InByIdStatus.cpp:

(JSC::InByIdStatus::computeFor):
(JSC::InByIdStatus::computeForStubInfo):
(JSC::InByIdStatus::computeForStubInfoWithoutExitSiteFeedback):

• bytecode/InByIdStatus.h:
• bytecode/InstanceOfStatus.cpp:

(JSC::InstanceOfStatus::computeFor):
(JSC::InstanceOfStatus::computeForStubInfo):

• bytecode/InstanceOfStatus.h:
• bytecode/PolyProtoAccessChain.cpp:

(JSC::PolyProtoAccessChain::create):
(JSC::PolyProtoAccessChain::needImpurePropertyWatchpoint const):
(JSC::PolyProtoAccessChain::dump const):

• bytecode/PolyProtoAccessChain.h:

(JSC::PolyProtoAccessChain::chain const):
(JSC::PolyProtoAccessChain::forEach const):
(JSC::PolyProtoAccessChain::slotBaseStructure const):
(JSC::PolyProtoAccessChain:: const): Deleted.

• bytecode/PolymorphicAccess.cpp:

(JSC::PolymorphicAccess::regenerate):

• bytecode/PutByIdStatus.cpp:

(JSC::PutByIdStatus::computeForStubInfo):

• bytecode/StructureStubInfo.cpp:

(JSC::StructureStubInfo::summary const):
(JSC::StructureStubInfo::summary):

• bytecode/StructureStubInfo.h:
• dfg/DFGCommonData.h:
• dfg/DFGDesiredWeakReferences.cpp:

(JSC::DFG::DesiredWeakReferences::reallyAdd):

• dfg/DFGPlan.cpp:

(JSC::DFG::Plan::finalizeWithoutNotifyingCallback):

• jit/Repatch.cpp:

(JSC::tryCacheGetBy):
(JSC::tryCachePutByID):
(JSC::tryCacheInByID):

File:

• trunk/Source/JavaScriptCore/bytecode/CodeBlock.cpp (modified) (3 diffs)

trunk/Source/JavaScriptCore/bytecode/CodeBlock.cpp

@@ -1134 +1134 @@
         dfgCommon->recordedStatuses.markIfCheap(visitor);
         
-        for (auto& weakReference : dfgCommon->weakStructureReferences)
-            weakReference->markIfCheap(visitor);
+        for (StructureID structureID : dfgCommon->weakStructureReferences)
+            vm.getStructure(structureID)->markIfCheap(visitor);
 
         for (auto& transition : dfgCommon->transitions) {
@@ -1194 +1194 @@
     }
     if (allAreLiveSoFar) {
-        for (unsigned i = 0; i < dfgCommon->weakStructureReferences.size(); ++i) {
-            if (!vm.heap.isMarked(dfgCommon->weakStructureReferences[i].get())) {
+        for (StructureID structureID : dfgCommon->weakStructureReferences) {
+            Structure* structure = vm.getStructure(structureID);
+            if (!vm.heap.isMarked(structure)) {
                 allAreLiveSoFar = false;
                 break;
@@ -1721 +1722 @@
         visitor.append(weakReference);
 
-    for (auto& weakStructureReference : dfgCommon->weakStructureReferences)
-        visitor.append(weakStructureReference);
+    for (StructureID structureID : dfgCommon->weakStructureReferences)
+        visitor.appendUnbarriered(visitor.vm().getStructure(structureID));
 
     dfgCommon->livenessHasBeenProved = true;