Attachment #217771 for bug #124824

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2013-11-24  Filip Pizlo  <fpizlo@apple.com>

        Create a new SymbolTable every time code is loaded so that the watchpoints don't get reused
        https://bugs.webkit.org/show_bug.cgi?id=124824

        Reviewed by NOBODY (OOPS!).
        
        This helps with one shot closure inference as well as closure variable constant
        inference, since without this, if code was reloaded from the cache then we would
        think that the first run was actually an Nth run. This would cause us to think that
        the watchpoint(s) should all be invalidated.

        * bytecode/CodeBlock.cpp:
        (JSC::CodeBlock::CodeBlock):
        (JSC::CodeBlock::stronglyVisitStrongReferences):
        * bytecode/CodeBlock.h:
        (JSC::CodeBlock::symbolTable):
        * runtime/Executable.cpp:
        (JSC::FunctionExecutable::symbolTable):
        * runtime/Executable.h:
        * runtime/SymbolTable.cpp:
        (JSC::SymbolTable::clone):
        * runtime/SymbolTable.h:

2013-11-23  Filip Pizlo  <fpizlo@apple.com>

        Fix more fallout from failed attempts at div/mod DFG strength reductions

Lines 1481-1486 CodeBlock::CodeBlock(CopyParsedBlockTag, Source/JavaScriptCore/bytecode/CodeBlock.cpp_sec1
- Source/JavaScriptCore/bytecode/CodeBlock.cpp +8 lines
1481	#endif	1481	#endif
1482	{	1482	{
1483	ASSERT(m_heap->isDeferred());	1483	ASSERT(m_heap->isDeferred());
		1484
		1485	if (SymbolTable* symbolTable = other.symbolTable())
		1486	m_symbolTable.set(*m_vm, m_ownerExecutable.get(), symbolTable);
		1487
1484	setNumParameters(other.numParameters());	1488	setNumParameters(other.numParameters());
1485	optimizeAfterWarmUp();	1489	optimizeAfterWarmUp();
1486	jitAfterWarmUp();	1490	jitAfterWarmUp();
Lines 1527-1532 CodeBlock::CodeBlock(ScriptExecutable* o Source/JavaScriptCore/bytecode/CodeBlock.cpp_sec2
1527	{	1531	{
1528	ASSERT(m_heap->isDeferred());	1532	ASSERT(m_heap->isDeferred());
1529		1533
		1534	if (SymbolTable* symbolTable = unlinkedCodeBlock->symbolTable())
		1535	m_symbolTable.set(m_vm, m_ownerExecutable.get(), symbolTable->clone(m_vm));
		1536
1530	ASSERT(m_source);	1537	ASSERT(m_source);
1531	setNumParameters(unlinkedCodeBlock->numParameters());	1538	setNumParameters(unlinkedCodeBlock->numParameters());
1532		1539
Lines 2338-2343 void CodeBlock::stronglyVisitStrongRefer Source/JavaScriptCore/bytecode/CodeBlock.cpp_sec3
2338	{	2345	{
2339	visitor.append(&m_globalObject);	2346	visitor.append(&m_globalObject);
2340	visitor.append(&m_ownerExecutable);	2347	visitor.append(&m_ownerExecutable);
		2348	visitor.append(&m_symbolTable);
2341	visitor.append(&m_unlinkedCode);	2349	visitor.append(&m_unlinkedCode);
2342	if (m_rareData)	2350	if (m_rareData)
2343	m_rareData->m_evalCodeCache.visitAggregate(visitor);	2351	m_rareData->m_evalCodeCache.visitAggregate(visitor);



    StringJumpTable& stringSwitchJumpTable(int tableIndex) { RELEASE_ASSERT(m_rareData); return m_rareData->m_stringSwitchJumpTables[tableIndex]; }


    SymbolTable* symbolTable() const { return m_symbolTable.get(); }

    EvalCodeCache& evalCodeCache() { createRareDataIfNecessary(); return m_rareData->m_evalCodeCache; }


    VM* m_vm;

    RefCountedArray<Instruction> m_instructions;
    WriteBarrier<SymbolTable> m_symbolTable;
    VirtualRegister m_thisRegister;
    VirtualRegister m_argumentsRegister;
    VirtualRegister m_activationRegister;

Lines 533-538 void FunctionExecutable::visitChildren(J Source/JavaScriptCore/runtime/Executable.cpp_sec1
- Source/JavaScriptCore/runtime/Executable.cpp +5 lines
533	visitor.append(&thisObject->m_unlinkedExecutable);	533	visitor.append(&thisObject->m_unlinkedExecutable);
534	}	534	}
535		535
		536	SymbolTable* FunctionExecutable::symbolTable(CodeSpecializationKind kind)
		537	{
		538	return codeBlockFor(kind)->symbolTable();
		539	}
		540
536	void FunctionExecutable::clearCodeIfNotCompiling()	541	void FunctionExecutable::clearCodeIfNotCompiling()
537	{	542	{
538	if (isCompiling())	543	if (isCompiling())

Lines 639-645 public: Source/JavaScriptCore/runtime/Executable.h_sec1
- Source/JavaScriptCore/runtime/Executable.h -1 / +1 lines
639	JSString* nameValue() const { return m_unlinkedExecutable->nameValue(); }	639	JSString* nameValue() const { return m_unlinkedExecutable->nameValue(); }
640	size_t parameterCount() const { return m_unlinkedExecutable->parameterCount(); } // Excluding 'this'!	640	size_t parameterCount() const { return m_unlinkedExecutable->parameterCount(); } // Excluding 'this'!
641	String paramString() const;	641	String paramString() const;
642	SymbolTable* symbolTable(CodeSpecializationKind kind) const { return m_unlinkedExecutable->symbolTable(kind); }	642	SymbolTable* symbolTable(CodeSpecializationKind kind);
643		643
644	void clearCodeIfNotCompiling();	644	void clearCodeIfNotCompiling();
645	void clearUnlinkedCodeForRecompilationIfNotCompiling();	645	void clearUnlinkedCodeForRecompilationIfNotCompiling();




SymbolTable::~SymbolTable() { }

SymbolTable* SymbolTable::clone(VM& vm)
{
    SymbolTable* result = SymbolTable::create(vm);
    
    result->m_parameterCountIncludingThis = m_parameterCountIncludingThis;
    result->m_usesNonStrictEval = m_usesNonStrictEval;
    result->m_captureStart = m_captureStart;
    result->m_captureEnd = m_captureEnd;
    
    Map::iterator iter = m_map.begin();
    Map::iterator end = m_map.end();
    for (; iter != end; ++iter) {
        result->m_map.add(
            iter->key,
            SymbolTableEntry(iter->value.getIndex(), iter->value.getAttributes()));
    }
    
    if (m_slowArguments) {
        result->m_slowArguments = std::make_unique<SlowArgument[]>(parameterCount());
        for (unsigned i = parameterCount(); i--;)
            result->m_slowArguments[i] = m_slowArguments[i];
    }
    
    return result;
}

} // namespace JSC


Lines 465-470 public: Source/JavaScriptCore/runtime/SymbolTable.h_sec1
- Source/JavaScriptCore/runtime/SymbolTable.h +2 lines
465	// 0 if we don't capture any arguments; parameterCount() in length if we do.	465	// 0 if we don't capture any arguments; parameterCount() in length if we do.
466	const SlowArgument* slowArguments() { return m_slowArguments.get(); }	466	const SlowArgument* slowArguments() { return m_slowArguments.get(); }
467	void setSlowArguments(std::unique_ptr<SlowArgument[]> slowArguments) { m_slowArguments = std::move(slowArguments); }	467	void setSlowArguments(std::unique_ptr<SlowArgument[]> slowArguments) { m_slowArguments = std::move(slowArguments); }
		468
		469	SymbolTable* clone(VM&);
468		470
469	DECLARE_EXPORT_INFO;	471	DECLARE_EXPORT_INFO;
470		472

Return to Bug 124824

Lines 722-728 public: Source/JavaScriptCore/bytecode/CodeBlock.h_sec1
- Source/JavaScriptCore/bytecode/CodeBlock.h -1 / +2 lines
722	StringJumpTable& stringSwitchJumpTable(int tableIndex) { RELEASE_ASSERT(m_rareData); return m_rareData->m_stringSwitchJumpTables[tableIndex]; }	722	StringJumpTable& stringSwitchJumpTable(int tableIndex) { RELEASE_ASSERT(m_rareData); return m_rareData->m_stringSwitchJumpTables[tableIndex]; }
723		723
724		724
725	SymbolTable* symbolTable() const { return m_unlinkedCode->symbolTable(); }	725	SymbolTable* symbolTable() const { return m_symbolTable.get(); }
726		726
727	EvalCodeCache& evalCodeCache() { createRareDataIfNecessary(); return m_rareData->m_evalCodeCache; }	727	EvalCodeCache& evalCodeCache() { createRareDataIfNecessary(); return m_rareData->m_evalCodeCache; }
728		728
Lines 1039-1044 private: Source/JavaScriptCore/bytecode/CodeBlock.h_sec2
1039	VM* m_vm;	1039	VM* m_vm;
1040		1040
1041	RefCountedArray<Instruction> m_instructions;	1041	RefCountedArray<Instruction> m_instructions;
		1042	WriteBarrier<SymbolTable> m_symbolTable;
1042	VirtualRegister m_thisRegister;	1043	VirtualRegister m_thisRegister;
1043	VirtualRegister m_argumentsRegister;	1044	VirtualRegister m_argumentsRegister;
1044	VirtualRegister m_activationRegister;	1045	VirtualRegister m_activationRegister;

Lines 109-113 SymbolTable::SymbolTable(VM& vm) Source/JavaScriptCore/runtime/SymbolTable.cpp_sec1
- Source/JavaScriptCore/runtime/SymbolTable.cpp +26 lines
109		109
110	SymbolTable::~SymbolTable() { }	110	SymbolTable::~SymbolTable() { }
111		111
		112	SymbolTable* SymbolTable::clone(VM& vm)
		113	{
		114	SymbolTable* result = SymbolTable::create(vm);
		115
		116	result->m_parameterCountIncludingThis = m_parameterCountIncludingThis;
		117	result->m_usesNonStrictEval = m_usesNonStrictEval;
		118	result->m_captureStart = m_captureStart;
		119	result->m_captureEnd = m_captureEnd;
		120
		121	Map::iterator iter = m_map.begin();
		122	Map::iterator end = m_map.end();
		123	for (; iter != end; ++iter) {
		124	result->m_map.add(
		125	iter->key,
		126	SymbolTableEntry(iter->value.getIndex(), iter->value.getAttributes()));
		127	}
		128
		129	if (m_slowArguments) {
		130	result->m_slowArguments = std::make_unique<SlowArgument[]>(parameterCount());
		131	for (unsigned i = parameterCount(); i--;)
		132	result->m_slowArguments[i] = m_slowArguments[i];
		133	}
		134
		135	return result;
		136	}
		137
112	} // namespace JSC	138	} // namespace JSC
113		139

Lines 1-3 Source/JavaScriptCore/ChangeLog_sec1
- Source/JavaScriptCore/ChangeLog +24 lines
		1	2013-11-24 Filip Pizlo <fpizlo@apple.com>
		2
		3	Create a new SymbolTable every time code is loaded so that the watchpoints don't get reused
		4	https://bugs.webkit.org/show_bug.cgi?id=124824
		5
		6	Reviewed by NOBODY (OOPS!).
		7
		8	This helps with one shot closure inference as well as closure variable constant
		9	inference, since without this, if code was reloaded from the cache then we would
		10	think that the first run was actually an Nth run. This would cause us to think that
		11	the watchpoint(s) should all be invalidated.
		12
		13	* bytecode/CodeBlock.cpp:
		14	(JSC::CodeBlock::CodeBlock):
		15	(JSC::CodeBlock::stronglyVisitStrongReferences):
		16	* bytecode/CodeBlock.h:
		17	(JSC::CodeBlock::symbolTable):
		18	* runtime/Executable.cpp:
		19	(JSC::FunctionExecutable::symbolTable):
		20	* runtime/Executable.h:
		21	* runtime/SymbolTable.cpp:
		22	(JSC::SymbolTable::clone):
		23	* runtime/SymbolTable.h:
		24
1	2013-11-23 Filip Pizlo <fpizlo@apple.com>	25	2013-11-23 Filip Pizlo <fpizlo@apple.com>
2		26
3	Fix more fallout from failed attempts at div/mod DFG strength reductions	27	Fix more fallout from failed attempts at div/mod DFG strength reductions