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DFG should not reparse code that was just parsed
https://bugs.webkit.org/show_bug.cgi?id=71977

Reviewed by Geoff Garen.

The instruction stream of a code block is now kept around until
the next GC. When doing either an optimizing compilation of an
executable, or inlining of an executable, we now try to find the
already preexisting bytecode. If we find it, we don't have to parse.
If we don't find it, we parse as before. Inlining takes the extra
step of caching code blocks, so if the same executable gets inlined
multiple times into the same caller, then we parse it at most once
even if prior to inlining that executable did not have any code
blocks with an instruction stream.

Also fixed a silly bug where the strict mode for various operations
was being determined by looking at the machine code block rather
than the inlinee.

To enable the delete-on-next-GC policy, I introduced the notion
of an ultra weak finalizer, which anyone can register during
tracing. This is thread-safe (for parallel GC) and
stop-the-world-safe (so calls to free() are postponed until the
world is resumed). This required reusing some facilities previously
created for WeakReferenceHarvester, so I created a common utility
class. I also retweaked the handling of WeakReferenceHarvesters,
since they should be executed during stop-the-world since in the
future we may want to allow them to call drain().

2% win on SunSpider. 2% win on V8, when run in my harness. Neutral
elsewhere.

* JavaScriptCore.xcodeproj/project.pbxproj:
* bytecode/CodeBlock.cpp:
(JSC::CodeBlock::CodeBlock):
(JSC::CodeBlock::visitAggregate):
(JSC::CodeBlock::copyPostParseDataFrom):
(JSC::CodeBlock::copyPostParseDataFromAlternative):
(JSC::CodeBlock::finalizeUnconditionally):
* bytecode/CodeBlock.h:
(JSC::CodeBlock::canProduceCopyWithBytecode):
(JSC::CodeBlock::discardBytecodeLater):
(JSC::CodeBlock::handleBytecodeDiscardingOpportunity):
(JSC::GlobalCodeBlock::GlobalCodeBlock):
(JSC::ProgramCodeBlock::ProgramCodeBlock):
(JSC::EvalCodeBlock::EvalCodeBlock):
(JSC::FunctionCodeBlock::FunctionCodeBlock):
(JSC::BytecodeDestructionBlocker::BytecodeDestructionBlocker):
(JSC::BytecodeDestructionBlocker::~BytecodeDestructionBlocker):
* dfg/DFGAssemblyHelpers.h:
(JSC::DFG::AssemblyHelpers::strictModeFor):
* dfg/DFGByteCodeCache.h: Added.
(JSC::DFG::CodeBlockKey::CodeBlockKey):
(JSC::DFG::CodeBlockKey::operator==):
(JSC::DFG::CodeBlockKey::hash):
(JSC::DFG::CodeBlockKey::executable):
(JSC::DFG::CodeBlockKey::kind):
(JSC::DFG::CodeBlockKey::isHashTableDeletedValue):
(JSC::DFG::CodeBlockKeyHash::hash):
(JSC::DFG::CodeBlockKeyHash::equal):
(JSC::DFG::ByteCodeCache::ByteCodeCache):
(JSC::DFG::ByteCodeCache::~ByteCodeCache):
(JSC::DFG::ByteCodeCache::get):
* dfg/DFGByteCodeParser.cpp:
(JSC::DFG::ByteCodeParser::handleInlining):
* dfg/DFGJITCodeGenerator32_64.cpp:
(JSC::DFG::JITCodeGenerator::cachedPutById):
* dfg/DFGJITCodeGenerator64.cpp:
(JSC::DFG::JITCodeGenerator::cachedPutById):
* dfg/DFGSpeculativeJIT64.cpp:
(JSC::DFG::SpeculativeJIT::compile):
* heap/Heap.cpp:
(JSC::Heap::finalizeUnconditionally):
(JSC::Heap::markRoots):
(JSC::Heap::collect):
* heap/Heap.h:
* heap/ListableHandler.h: Added.
(JSC::ListableHandler::ListableHandler):
(JSC::ListableHandler::~ListableHandler):
(JSC::ListableHandler::List::List):
(JSC::ListableHandler::List::addNotThreadSafe):
(JSC::ListableHandler::List::addThreadSafe):
(JSC::ListableHandler::List::hasNext):
(JSC::ListableHandler::List::removeNext):
* heap/MarkStack.cpp:
(JSC::MarkStackThreadSharedData::MarkStackThreadSharedData):
(JSC::SlotVisitor::harvestWeakReferences):
(JSC::SlotVisitor::finalizeUnconditionally):
* heap/MarkStack.h:
(JSC::MarkStack::addWeakReferenceHarvester):
(JSC::MarkStack::addUnconditionalFinalizer):
* heap/SlotVisitor.h:
* heap/UnconditionalFinalizer.h: Added.
(JSC::UnconditionalFinalizer::~UnconditionalFinalizer):
* heap/WeakReferenceHarvester.h:
(JSC::WeakReferenceHarvester::WeakReferenceHarvester):
(JSC::WeakReferenceHarvester::~WeakReferenceHarvester):
* runtime/Executable.cpp:
(JSC::EvalExecutable::compileInternal):
(JSC::ProgramExecutable::compileInternal):
(JSC::FunctionExecutable::baselineCodeBlockFor):
(JSC::FunctionExecutable::codeBlockWithBytecodeFor):
(JSC::FunctionExecutable::produceCodeBlockFor):
(JSC::FunctionExecutable::compileForCallInternal):
(JSC::FunctionExecutable::compileForConstructInternal):
* runtime/Executable.h:
(JSC::FunctionExecutable::profiledCodeBlockFor):



Canonical link: https://commits.webkit.org/88460@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@99898 268f45cc-cd09-0410-ab3c-d52691b4dbfc
  • Loading branch information
pizlonator committed Nov 10, 2011
1 parent c406ab9 commit 0a2311087370a3439932dfdc2a0614f78274b983
@@ -1,3 +1,113 @@
2011-11-10 Filip Pizlo <fpizlo@apple.com>

DFG should not reparse code that was just parsed
https://bugs.webkit.org/show_bug.cgi?id=71977

Reviewed by Geoff Garen.

The instruction stream of a code block is now kept around until
the next GC. When doing either an optimizing compilation of an
executable, or inlining of an executable, we now try to find the
already preexisting bytecode. If we find it, we don't have to parse.
If we don't find it, we parse as before. Inlining takes the extra
step of caching code blocks, so if the same executable gets inlined
multiple times into the same caller, then we parse it at most once
even if prior to inlining that executable did not have any code
blocks with an instruction stream.

Also fixed a silly bug where the strict mode for various operations
was being determined by looking at the machine code block rather
than the inlinee.

To enable the delete-on-next-GC policy, I introduced the notion
of an ultra weak finalizer, which anyone can register during
tracing. This is thread-safe (for parallel GC) and
stop-the-world-safe (so calls to free() are postponed until the
world is resumed). This required reusing some facilities previously
created for WeakReferenceHarvester, so I created a common utility
class. I also retweaked the handling of WeakReferenceHarvesters,
since they should be executed during stop-the-world since in the
future we may want to allow them to call drain().

2% win on SunSpider. 2% win on V8, when run in my harness. Neutral
elsewhere.

* JavaScriptCore.xcodeproj/project.pbxproj:
* bytecode/CodeBlock.cpp:
(JSC::CodeBlock::CodeBlock):
(JSC::CodeBlock::visitAggregate):
(JSC::CodeBlock::copyPostParseDataFrom):
(JSC::CodeBlock::copyPostParseDataFromAlternative):
(JSC::CodeBlock::finalizeUnconditionally):
* bytecode/CodeBlock.h:
(JSC::CodeBlock::canProduceCopyWithBytecode):
(JSC::CodeBlock::discardBytecodeLater):
(JSC::CodeBlock::handleBytecodeDiscardingOpportunity):
(JSC::GlobalCodeBlock::GlobalCodeBlock):
(JSC::ProgramCodeBlock::ProgramCodeBlock):
(JSC::EvalCodeBlock::EvalCodeBlock):
(JSC::FunctionCodeBlock::FunctionCodeBlock):
(JSC::BytecodeDestructionBlocker::BytecodeDestructionBlocker):
(JSC::BytecodeDestructionBlocker::~BytecodeDestructionBlocker):
* dfg/DFGAssemblyHelpers.h:
(JSC::DFG::AssemblyHelpers::strictModeFor):
* dfg/DFGByteCodeCache.h: Added.
(JSC::DFG::CodeBlockKey::CodeBlockKey):
(JSC::DFG::CodeBlockKey::operator==):
(JSC::DFG::CodeBlockKey::hash):
(JSC::DFG::CodeBlockKey::executable):
(JSC::DFG::CodeBlockKey::kind):
(JSC::DFG::CodeBlockKey::isHashTableDeletedValue):
(JSC::DFG::CodeBlockKeyHash::hash):
(JSC::DFG::CodeBlockKeyHash::equal):
(JSC::DFG::ByteCodeCache::ByteCodeCache):
(JSC::DFG::ByteCodeCache::~ByteCodeCache):
(JSC::DFG::ByteCodeCache::get):
* dfg/DFGByteCodeParser.cpp:
(JSC::DFG::ByteCodeParser::handleInlining):
* dfg/DFGJITCodeGenerator32_64.cpp:
(JSC::DFG::JITCodeGenerator::cachedPutById):
* dfg/DFGJITCodeGenerator64.cpp:
(JSC::DFG::JITCodeGenerator::cachedPutById):
* dfg/DFGSpeculativeJIT64.cpp:
(JSC::DFG::SpeculativeJIT::compile):
* heap/Heap.cpp:
(JSC::Heap::finalizeUnconditionally):
(JSC::Heap::markRoots):
(JSC::Heap::collect):
* heap/Heap.h:
* heap/ListableHandler.h: Added.
(JSC::ListableHandler::ListableHandler):
(JSC::ListableHandler::~ListableHandler):
(JSC::ListableHandler::List::List):
(JSC::ListableHandler::List::addNotThreadSafe):
(JSC::ListableHandler::List::addThreadSafe):
(JSC::ListableHandler::List::hasNext):
(JSC::ListableHandler::List::removeNext):
* heap/MarkStack.cpp:
(JSC::MarkStackThreadSharedData::MarkStackThreadSharedData):
(JSC::SlotVisitor::harvestWeakReferences):
(JSC::SlotVisitor::finalizeUnconditionally):
* heap/MarkStack.h:
(JSC::MarkStack::addWeakReferenceHarvester):
(JSC::MarkStack::addUnconditionalFinalizer):
* heap/SlotVisitor.h:
* heap/UnconditionalFinalizer.h: Added.
(JSC::UnconditionalFinalizer::~UnconditionalFinalizer):
* heap/WeakReferenceHarvester.h:
(JSC::WeakReferenceHarvester::WeakReferenceHarvester):
(JSC::WeakReferenceHarvester::~WeakReferenceHarvester):
* runtime/Executable.cpp:
(JSC::EvalExecutable::compileInternal):
(JSC::ProgramExecutable::compileInternal):
(JSC::FunctionExecutable::baselineCodeBlockFor):
(JSC::FunctionExecutable::codeBlockWithBytecodeFor):
(JSC::FunctionExecutable::produceCodeBlockFor):
(JSC::FunctionExecutable::compileForCallInternal):
(JSC::FunctionExecutable::compileForConstructInternal):
* runtime/Executable.h:
(JSC::FunctionExecutable::profiledCodeBlockFor):

2011-11-10 Gavin Barraclough <barraclough@apple.com>

Add ARMv7 register info for the DFG JIT
@@ -54,6 +54,8 @@
0F426A481460CBB300131F8F /* ValueRecovery.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F426A451460CBAB00131F8F /* ValueRecovery.h */; settings = {ATTRIBUTES = (Private, ); }; };
0F426A491460CBB700131F8F /* VirtualRegister.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F426A461460CBAB00131F8F /* VirtualRegister.h */; settings = {ATTRIBUTES = (Private, ); }; };
0F426A4B1460CD6E00131F8F /* DataFormat.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F426A4A1460CD6B00131F8F /* DataFormat.h */; settings = {ATTRIBUTES = (Private, ); }; };
0F431738146BAC69007E3890 /* ListableHandler.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F431736146BAC65007E3890 /* ListableHandler.h */; settings = {ATTRIBUTES = (Private, ); }; };
0F5F08CF146C7633000472A9 /* UnconditionalFinalizer.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F5F08CE146C762F000472A9 /* UnconditionalFinalizer.h */; settings = {ATTRIBUTES = (Private, ); }; };
0F620174143FCD330068B77C /* DFGVariableAccessData.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F620172143FCD2F0068B77C /* DFGVariableAccessData.h */; settings = {ATTRIBUTES = (Private, ); }; };
0F620175143FCD370068B77C /* DFGOperands.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F620171143FCD2F0068B77C /* DFGOperands.h */; settings = {ATTRIBUTES = (Private, ); }; };
0F620176143FCD3B0068B77C /* DFGBasicBlock.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F620170143FCD2F0068B77C /* DFGBasicBlock.h */; settings = {ATTRIBUTES = (Private, ); }; };
@@ -829,6 +831,9 @@
0F426A451460CBAB00131F8F /* ValueRecovery.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ValueRecovery.h; sourceTree = "<group>"; };
0F426A461460CBAB00131F8F /* VirtualRegister.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = VirtualRegister.h; sourceTree = "<group>"; };
0F426A4A1460CD6B00131F8F /* DataFormat.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = DataFormat.h; sourceTree = "<group>"; };
0F431736146BAC65007E3890 /* ListableHandler.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ListableHandler.h; sourceTree = "<group>"; };
0F5F08CC146BE602000472A9 /* DFGByteCodeCache.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = DFGByteCodeCache.h; path = dfg/DFGByteCodeCache.h; sourceTree = "<group>"; };
0F5F08CE146C762F000472A9 /* UnconditionalFinalizer.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = UnconditionalFinalizer.h; sourceTree = "<group>"; };
0F62016D143FCD2F0068B77C /* DFGAbstractState.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = DFGAbstractState.cpp; path = dfg/DFGAbstractState.cpp; sourceTree = "<group>"; };
0F62016E143FCD2F0068B77C /* DFGAbstractState.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = DFGAbstractState.h; path = dfg/DFGAbstractState.h; sourceTree = "<group>"; };
0F62016F143FCD2F0068B77C /* DFGAbstractValue.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = DFGAbstractValue.h; path = dfg/DFGAbstractValue.h; sourceTree = "<group>"; };
@@ -1701,6 +1706,8 @@
142E312A134FF0A600AFADB5 /* heap */ = {
isa = PBXGroup;
children = (
0F5F08CE146C762F000472A9 /* UnconditionalFinalizer.h */,
0F431736146BAC65007E3890 /* ListableHandler.h */,
0FD82F281426CA5A00179C94 /* JettisonedCodeBlocks.cpp */,
0FD82F291426CA5A00179C94 /* JettisonedCodeBlocks.h */,
A70456AE1427FB030037DA68 /* AllocationSpace.cpp */,
@@ -2317,6 +2324,7 @@
86EC9DB31328DF44002B2AD7 /* dfg */ = {
isa = PBXGroup;
children = (
0F5F08CC146BE602000472A9 /* DFGByteCodeCache.h */,
0FC0979F146B28C700CF2442 /* DFGThunks.cpp */,
0FC097A0146B28C700CF2442 /* DFGThunks.h */,
0FC0979D146B271E00CF2442 /* DFGCorrectableJumpPoint.cpp */,
@@ -2943,6 +2951,8 @@
0FC0977114693AF500CF2442 /* DFGOSRExitCompiler.h in Headers */,
0FC0979C146A772500CF2442 /* DFGCorrectableJumpPoint.h in Headers */,
0FC097A2146B28CC00CF2442 /* DFGThunks.h in Headers */,
0F431738146BAC69007E3890 /* ListableHandler.h in Headers */,
0F5F08CF146C7633000472A9 /* UnconditionalFinalizer.h in Headers */,
);
runOnlyForDeploymentPostprocessing = 0;
};
@@ -1407,13 +1407,66 @@ void CodeBlock::dumpStatistics()
#endif
}

CodeBlock::CodeBlock(CopyParsedBlockTag, CodeBlock& other, SymbolTable* symTab)
: m_globalObject(other.m_globalObject)
, m_heap(other.m_heap)
, m_numCalleeRegisters(other.m_numCalleeRegisters)
, m_numVars(other.m_numVars)
, m_numCapturedVars(other.m_numCapturedVars)
, m_numParameters(other.m_numParameters)
, m_isConstructor(other.m_isConstructor)
, m_shouldDiscardBytecode(false)
, m_ownerExecutable(*other.m_globalData, other.m_ownerExecutable.get(), other.m_ownerExecutable.get())
, m_globalData(other.m_globalData)
, m_instructions(other.m_instructions)
, m_instructionCount(other.m_instructionCount)
, m_thisRegister(other.m_thisRegister)
, m_argumentsRegister(other.m_argumentsRegister)
, m_activationRegister(other.m_activationRegister)
, m_needsFullScopeChain(other.m_needsFullScopeChain)
, m_usesEval(other.m_usesEval)
, m_isNumericCompareFunction(other.m_isNumericCompareFunction)
, m_isStrictMode(other.m_isStrictMode)
, m_codeType(other.m_codeType)
, m_source(other.m_source)
, m_sourceOffset(other.m_sourceOffset)
, m_globalResolveInfos(other.m_globalResolveInfos)
, m_jumpTargets(other.m_jumpTargets)
, m_loopTargets(other.m_loopTargets)
, m_identifiers(other.m_identifiers)
, m_constantRegisters(other.m_constantRegisters)
, m_functionDecls(other.m_functionDecls)
, m_functionExprs(other.m_functionExprs)
, m_symbolTable(symTab)
, m_speculativeSuccessCounter(0)
, m_speculativeFailCounter(0)
, m_optimizationDelayCounter(0)
, m_reoptimizationRetryCounter(0)
{
optimizeAfterWarmUp();

if (other.m_rareData) {
createRareDataIfNecessary();

m_rareData->m_exceptionHandlers = other.m_rareData->m_exceptionHandlers;
m_rareData->m_regexps = other.m_rareData->m_regexps;
m_rareData->m_constantBuffers = other.m_rareData->m_constantBuffers;
m_rareData->m_immediateSwitchJumpTables = other.m_rareData->m_immediateSwitchJumpTables;
m_rareData->m_characterSwitchJumpTables = other.m_rareData->m_characterSwitchJumpTables;
m_rareData->m_stringSwitchJumpTables = other.m_rareData->m_stringSwitchJumpTables;
m_rareData->m_expressionInfo = other.m_rareData->m_expressionInfo;
m_rareData->m_lineInfo = other.m_rareData->m_lineInfo;
}
}

CodeBlock::CodeBlock(ScriptExecutable* ownerExecutable, CodeType codeType, JSGlobalObject *globalObject, PassRefPtr<SourceProvider> sourceProvider, unsigned sourceOffset, SymbolTable* symTab, bool isConstructor, PassOwnPtr<CodeBlock> alternative)
: m_globalObject(globalObject->globalData(), ownerExecutable, globalObject)
, m_heap(&m_globalObject->globalData().heap)
, m_numCalleeRegisters(0)
, m_numVars(0)
, m_numParameters(0)
, m_isConstructor(isConstructor)
, m_shouldDiscardBytecode(false)
, m_ownerExecutable(globalObject->globalData(), ownerExecutable, ownerExecutable)
, m_globalData(0)
, m_instructions(adoptRef(new Instructions))
@@ -1595,6 +1648,13 @@ void CodeBlock::visitAggregate(SlotVisitor& visitor)
for (unsigned profileIndex = 0; profileIndex < numberOfValueProfiles(); ++profileIndex)
valueProfile(profileIndex)->computeUpdatedPrediction();
#endif

#if ENABLE(JIT) && !ENABLE(OPCODE_SAMPLING)
// Kill off some bytecode. We can't do it here because we don't want to accidentally
// call into malloc while in stop-the-world GC mode.
if (hasInstructions() && m_shouldDiscardBytecode)
visitor.addUnconditionalFinalizer(this);
#endif
}

HandlerInfo* CodeBlock::handlerForBytecodeOffset(unsigned bytecodeOffset)
@@ -1821,7 +1881,7 @@ inline void replaceExistingEntries(Vector<T>& target, Vector<T>& source)
target[i] = source[i];
}

void CodeBlock::copyDataFrom(CodeBlock* alternative)
void CodeBlock::copyPostParseDataFrom(CodeBlock* alternative)
{
if (!alternative)
return;
@@ -1833,9 +1893,9 @@ void CodeBlock::copyDataFrom(CodeBlock* alternative)
replaceExistingEntries(m_rareData->m_constantBuffers, alternative->m_rareData->m_constantBuffers);
}

void CodeBlock::copyDataFromAlternative()
void CodeBlock::copyPostParseDataFromAlternative()
{
copyDataFrom(m_alternative.get());
copyPostParseDataFrom(m_alternative.get());
}

#if ENABLE(JIT)
@@ -1917,6 +1977,15 @@ void FunctionCodeBlock::jettison(JSGlobalData& globalData)
}
#endif

void CodeBlock::finalizeUnconditionally()
{
#if ENABLE(OPCODE_SAMPLING) || !ENABLE(JIT)
ASSERT_NOT_REACHED();
#endif
ASSERT(m_shouldDiscardBytecode);
discardBytecode();
}

#if ENABLE(VALUE_PROFILER)
bool CodeBlock::shouldOptimizeNow()
{

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