Changeset 226725 in webkit for trunk/Source/JavaScriptCore/bytecode/CodeBlock.h

Timestamp:

Jan 10, 2018, 11:41:12 AM (8 years ago)

Author:

[email protected]

Message:

Unreviewed, rolling out r226667 and r226673.
​https://bugs.webkit.org/show_bug.cgi?id=181488

This caused a flaky crash. (Requested by mlewis13 on #webkit).

Reverted changesets:

"CodeBlocks should be in IsoSubspaces"
​https://bugs.webkit.org/show_bug.cgi?id=180884
​https://trac.webkit.org/changeset/226667

"REGRESSION (r226667): CodeBlocks should be in IsoSubspaces"
​https://bugs.webkit.org/show_bug.cgi?id=180884
​https://trac.webkit.org/changeset/226673

File:

• trunk/Source/JavaScriptCore/bytecode/CodeBlock.h (modified) (11 diffs)

trunk/Source/JavaScriptCore/bytecode/CodeBlock.h

@@ -88 +88 @@
 class CodeBlockSet;
 class ExecState;
-class ExecutableToCodeBlockEdge;
 class JSModuleEnvironment;
 class LLIntOffsetsExtractor;
@@ -109 +108 @@
     friend class LLIntOffsetsExtractor;
 
+    struct UnconditionalFinalizer : public JSC::UnconditionalFinalizer {
+        UnconditionalFinalizer(CodeBlock& codeBlock)
+            : codeBlock(codeBlock)
+        { }
+        void finalizeUnconditionally() override;
+        CodeBlock& codeBlock;
+    };
+
+    struct WeakReferenceHarvester : public JSC::WeakReferenceHarvester {
+        WeakReferenceHarvester(CodeBlock& codeBlock)
+            : codeBlock(codeBlock)
+        { }
+        void visitWeakReferences(SlotVisitor&) override;
+        CodeBlock& codeBlock;
+    };
+
 public:
 
@@ -114 +129 @@
 
     static const unsigned StructureFlags = Base::StructureFlags | StructureIsImmortal;
-    static const bool needsDestruction = true;
-
-    template<typename>
-    static void subspaceFor(VM&) { }
 
     DECLARE_INFO;
@@ -127 +138 @@
     void finishCreation(VM&, CopyParsedBlockTag, CodeBlock& other);
     bool finishCreation(VM&, ScriptExecutable* ownerExecutable, UnlinkedCodeBlock*, JSScope*);
-    
-    void finishCreationCommon(VM&);
 
     WriteBarrier<JSGlobalObject> m_globalObject;
@@ -192 +201 @@
     static void visitChildren(JSCell*, SlotVisitor&);
     void visitChildren(SlotVisitor&);
-    void finalizeUnconditionally(VM&);
+    void visitWeakly(SlotVisitor&);
+    void clearVisitWeaklyHasBeenCalled();
 
     void dumpSource();
@@ -360 +370 @@
     ExecutableBase* ownerExecutable() const { return m_ownerExecutable.get(); }
     ScriptExecutable* ownerScriptExecutable() const { return jsCast<ScriptExecutable*>(m_ownerExecutable.get()); }
-    
-    ExecutableToCodeBlockEdge* ownerEdge() const { return m_ownerEdge.get(); }
 
     VM* vm() const { return m_poisonedVM.unpoisoned(); }
@@ -822 +830 @@
     mutable ConcurrentJSLock m_lock;
 
+    bool m_visitWeaklyHasBeenCalled;
+
     bool m_shouldAlwaysBeInlined; // Not a bitfield because the JIT wants to store to it.
 
@@ -909 +919 @@
 private:
     friend class CodeBlockSet;
-    friend class ExecutableToCodeBlockEdge;
 
     BytecodeLivenessAnalysis& livenessAnalysisSlow();
@@ -974 +983 @@
     };
     WriteBarrier<ExecutableBase> m_ownerExecutable;
-    WriteBarrier<ExecutableToCodeBlockEdge> m_ownerEdge;
     ConstExprPoisoned<CodeBlockPoison, VM*> m_poisonedVM;
 
@@ -1039 +1047 @@
 
     std::unique_ptr<RareData> m_rareData;
+
+    PoisonedUniquePtr<CodeBlockPoison, UnconditionalFinalizer> m_unconditionalFinalizer;
+    PoisonedUniquePtr<CodeBlockPoison, WeakReferenceHarvester> m_weakReferenceHarvester;
 };
 
@@ -1063 +1074 @@
 {
     return uncheckedR(reg.offset());
+}
+
+inline void CodeBlock::clearVisitWeaklyHasBeenCalled()
+{
+    m_visitWeaklyHasBeenCalled = false;
 }