Attachment 238689 Details for Bug 136330 – so much fix

[patch] so much fix

blah.patch (text/plain), 269.19 KB, created by Filip Pizlo on 2014-09-25 17:47:51 PDT

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Creator: Filip Pizlo

Created: 2014-09-25 17:47:51 PDT

Size: 269.19 KB

patch

obsolete

>Index: Source/JavaScriptCore/ChangeLog
>===================================================================
>--- Source/JavaScriptCore/ChangeLog	(revision 173973)
>+++ Source/JavaScriptCore/ChangeLog	(working copy)
>@@ -1,3 +1,292 @@
>+2014-09-25  Filip Pizlo  <fpizlo@apple.com>
>+
>+        FTL should sink object allocations
>+        https://bugs.webkit.org/show_bug.cgi?id=136330
>+
>+        Reviewed by Oliver Hunt.
>+        
>+        This adds a comprehensive infrastructure for sinking object allocations in DFG SSA form. The
>+        ultimate goal of sinking is to sink an allocation "past the points of its death" - i.e. to
>+        eliminate it completely. The way sinking reasons about the CFG means that it resembles a
>+        partial escape analysis: we create paths through a function where some allocation(s) don't
>+        have to be done at all even if there are other paths along which those allocations still have
>+        to happen. But it also produces other side benefits. Even if an allocation isn't eliminated
>+        along any path, the act of sinking reduces the number of barriers that have to execute.
>+        
>+        Because this was a fairly ambituous SSA analysis and transformation, I added a bunch of C++11
>+        sugar to the DFG's internal APIs to allow for easier iteration over blocks, nodes, and
>+        successors; and to add more functor goodness to allow for more lambdas.
>+        
>+        This is just the beginning. The bug has a bunch of other bugs that depend on it. So far this
>+        is a spectacular speed-up on microbenchmarks but it's still too limited to affect big
>+        benchmarks. I think it's best to land it in its current form and then to worry about the big
>+        benchmarks in subsequent work (see bug 137126).
>+
>+        * CMakeLists.txt:
>+        * JavaScriptCore.vcxproj/JavaScriptCore.vcxproj:
>+        * JavaScriptCore.xcodeproj/project.pbxproj:
>+        * bytecode/StructureSet.h:
>+        (JSC::StructureSet::iterator::iterator):
>+        (JSC::StructureSet::iterator::operator*):
>+        (JSC::StructureSet::iterator::operator++):
>+        (JSC::StructureSet::iterator::operator==):
>+        (JSC::StructureSet::iterator::operator!=):
>+        (JSC::StructureSet::begin):
>+        (JSC::StructureSet::end):
>+        * dfg/DFGAbstractInterpreter.h:
>+        (JSC::DFG::AbstractInterpreter::phiChildren):
>+        * dfg/DFGAbstractInterpreterInlines.h:
>+        (JSC::DFG::AbstractInterpreter<AbstractStateType>::AbstractInterpreter):
>+        (JSC::DFG::AbstractInterpreter<AbstractStateType>::startExecuting):
>+        (JSC::DFG::AbstractInterpreter<AbstractStateType>::executeEffects):
>+        (JSC::DFG::AbstractInterpreter<AbstractStateType>::execute):
>+        * dfg/DFGAvailability.h:
>+        (JSC::DFG::Availability::shouldUseNode):
>+        (JSC::DFG::Availability::isFlushUseful):
>+        (JSC::DFG::Availability::isDead):
>+        (JSC::DFG::Availability::operator!=):
>+        * dfg/DFGAvailabilityMap.cpp: Added.
>+        (JSC::DFG::AvailabilityMap::prune):
>+        (JSC::DFG::AvailabilityMap::clear):
>+        (JSC::DFG::AvailabilityMap::dump):
>+        (JSC::DFG::AvailabilityMap::operator==):
>+        (JSC::DFG::AvailabilityMap::merge):
>+        * dfg/DFGAvailabilityMap.h: Added.
>+        (JSC::DFG::AvailabilityMap::forEachAvailability):
>+        * dfg/DFGBasicBlock.cpp:
>+        (JSC::DFG::BasicBlock::SSAData::SSAData):
>+        * dfg/DFGBasicBlock.h:
>+        (JSC::DFG::BasicBlock::begin):
>+        (JSC::DFG::BasicBlock::end):
>+        (JSC::DFG::BasicBlock::SuccessorsIterable::SuccessorsIterable):
>+        (JSC::DFG::BasicBlock::SuccessorsIterable::iterator::iterator):
>+        (JSC::DFG::BasicBlock::SuccessorsIterable::iterator::operator*):
>+        (JSC::DFG::BasicBlock::SuccessorsIterable::iterator::operator++):
>+        (JSC::DFG::BasicBlock::SuccessorsIterable::iterator::operator==):
>+        (JSC::DFG::BasicBlock::SuccessorsIterable::iterator::operator!=):
>+        (JSC::DFG::BasicBlock::SuccessorsIterable::begin):
>+        (JSC::DFG::BasicBlock::SuccessorsIterable::end):
>+        (JSC::DFG::BasicBlock::successors):
>+        * dfg/DFGClobberize.h:
>+        (JSC::DFG::clobberize):
>+        * dfg/DFGConstantFoldingPhase.cpp:
>+        (JSC::DFG::ConstantFoldingPhase::foldConstants):
>+        * dfg/DFGDoesGC.cpp:
>+        (JSC::DFG::doesGC):
>+        * dfg/DFGFixupPhase.cpp:
>+        (JSC::DFG::FixupPhase::fixupNode):
>+        * dfg/DFGFlushedAt.cpp:
>+        (JSC::DFG::FlushedAt::dump):
>+        * dfg/DFGFlushedAt.h:
>+        (JSC::DFG::FlushedAt::FlushedAt):
>+        * dfg/DFGGraph.cpp:
>+        (JSC::DFG::Graph::dump):
>+        (JSC::DFG::Graph::dumpBlockHeader):
>+        (JSC::DFG::Graph::mergeRelevantToOSR):
>+        (JSC::DFG::Graph::invalidateCFG):
>+        * dfg/DFGGraph.h:
>+        (JSC::DFG::Graph::NaturalBlockIterable::NaturalBlockIterable):
>+        (JSC::DFG::Graph::NaturalBlockIterable::iterator::iterator):
>+        (JSC::DFG::Graph::NaturalBlockIterable::iterator::operator*):
>+        (JSC::DFG::Graph::NaturalBlockIterable::iterator::operator++):
>+        (JSC::DFG::Graph::NaturalBlockIterable::iterator::operator==):
>+        (JSC::DFG::Graph::NaturalBlockIterable::iterator::operator!=):
>+        (JSC::DFG::Graph::NaturalBlockIterable::iterator::findNext):
>+        (JSC::DFG::Graph::NaturalBlockIterable::begin):
>+        (JSC::DFG::Graph::NaturalBlockIterable::end):
>+        (JSC::DFG::Graph::blocksInNaturalOrder):
>+        (JSC::DFG::Graph::doToChildrenWithNode):
>+        (JSC::DFG::Graph::doToChildren):
>+        * dfg/DFGHeapLocation.cpp:
>+        (WTF::printInternal):
>+        * dfg/DFGHeapLocation.h:
>+        * dfg/DFGInsertOSRHintsForUpdate.cpp: Added.
>+        (JSC::DFG::insertOSRHintsForUpdate):
>+        * dfg/DFGInsertOSRHintsForUpdate.h: Added.
>+        * dfg/DFGInsertionSet.h:
>+        (JSC::DFG::InsertionSet::graph):
>+        * dfg/DFGMayExit.cpp:
>+        (JSC::DFG::mayExit):
>+        * dfg/DFGNode.h:
>+        (JSC::DFG::Node::convertToPutByOffsetHint):
>+        (JSC::DFG::Node::convertToPutStructureHint):
>+        (JSC::DFG::Node::convertToPhantomNewObject):
>+        (JSC::DFG::Node::isCellConstant):
>+        (JSC::DFG::Node::castConstant):
>+        (JSC::DFG::Node::hasIdentifier):
>+        (JSC::DFG::Node::hasStorageAccessData):
>+        (JSC::DFG::Node::hasObjectMaterializationData):
>+        (JSC::DFG::Node::objectMaterializationData):
>+        (JSC::DFG::Node::isPhantomObjectAllocation):
>+        * dfg/DFGNodeType.h:
>+        * dfg/DFGOSRAvailabilityAnalysisPhase.cpp:
>+        (JSC::DFG::OSRAvailabilityAnalysisPhase::run):
>+        (JSC::DFG::LocalOSRAvailabilityCalculator::endBlock):
>+        (JSC::DFG::LocalOSRAvailabilityCalculator::executeNode):
>+        * dfg/DFGOSRAvailabilityAnalysisPhase.h:
>+        * dfg/DFGObjectAllocationSinkingPhase.cpp: Added.
>+        (JSC::DFG::ObjectAllocationSinkingPhase::ObjectAllocationSinkingPhase):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::run):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::performSinking):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::determineMaterializationPoints):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::placeMaterializationPoints):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::lowerNonReadingOperationsOnPhantomAllocations):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::promoteSunkenFields):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::resolve):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::handleNode):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::createMaterialize):
>+        (JSC::DFG::ObjectAllocationSinkingPhase::populateMaterialize):
>+        (JSC::DFG::performObjectAllocationSinking):
>+        * dfg/DFGObjectAllocationSinkingPhase.h: Added.
>+        * dfg/DFGObjectMaterializationData.cpp: Added.
>+        (JSC::DFG::PhantomPropertyValue::dump):
>+        (JSC::DFG::ObjectMaterializationData::dump):
>+        (JSC::DFG::ObjectMaterializationData::oneWaySimilarityScore):
>+        (JSC::DFG::ObjectMaterializationData::similarityScore):
>+        * dfg/DFGObjectMaterializationData.h: Added.
>+        (JSC::DFG::PhantomPropertyValue::PhantomPropertyValue):
>+        (JSC::DFG::PhantomPropertyValue::operator==):
>+        * dfg/DFGPhantomCanonicalizationPhase.cpp:
>+        (JSC::DFG::PhantomCanonicalizationPhase::run):
>+        * dfg/DFGPhantomRemovalPhase.cpp:
>+        (JSC::DFG::PhantomRemovalPhase::run):
>+        * dfg/DFGPhiChildren.cpp: Added.
>+        (JSC::DFG::PhiChildren::PhiChildren):
>+        (JSC::DFG::PhiChildren::~PhiChildren):
>+        (JSC::DFG::PhiChildren::upsilonsOf):
>+        * dfg/DFGPhiChildren.h: Added.
>+        (JSC::DFG::PhiChildren::forAllIncomingValues):
>+        (JSC::DFG::PhiChildren::forAllTransitiveIncomingValues):
>+        * dfg/DFGPlan.cpp:
>+        (JSC::DFG::Plan::compileInThreadImpl):
>+        * dfg/DFGPrePostNumbering.cpp: Added.
>+        (JSC::DFG::PrePostNumbering::PrePostNumbering):
>+        (JSC::DFG::PrePostNumbering::~PrePostNumbering):
>+        (JSC::DFG::PrePostNumbering::compute):
>+        (WTF::printInternal):
>+        * dfg/DFGPrePostNumbering.h: Added.
>+        (JSC::DFG::PrePostNumbering::preNumber):
>+        (JSC::DFG::PrePostNumbering::postNumber):
>+        (JSC::DFG::PrePostNumbering::isStrictAncestorOf):
>+        (JSC::DFG::PrePostNumbering::isAncestorOf):
>+        (JSC::DFG::PrePostNumbering::isStrictDescendantOf):
>+        (JSC::DFG::PrePostNumbering::isDescendantOf):
>+        (JSC::DFG::PrePostNumbering::edgeKind):
>+        * dfg/DFGPredictionPropagationPhase.cpp:
>+        (JSC::DFG::PredictionPropagationPhase::propagate):
>+        * dfg/DFGPromoteHeapAccess.h: Added.
>+        (JSC::DFG::promoteHeapAccess):
>+        * dfg/DFGPromotedHeapLocation.cpp: Added.
>+        (JSC::DFG::PromotedLocationDescriptor::dump):
>+        (JSC::DFG::PromotedHeapLocation::createHint):
>+        (JSC::DFG::PromotedHeapLocation::dump):
>+        (WTF::printInternal):
>+        * dfg/DFGPromotedHeapLocation.h: Added.
>+        (JSC::DFG::PromotedLocationDescriptor::PromotedLocationDescriptor):
>+        (JSC::DFG::PromotedLocationDescriptor::operator!):
>+        (JSC::DFG::PromotedLocationDescriptor::kind):
>+        (JSC::DFG::PromotedLocationDescriptor::info):
>+        (JSC::DFG::PromotedLocationDescriptor::hash):
>+        (JSC::DFG::PromotedLocationDescriptor::operator==):
>+        (JSC::DFG::PromotedLocationDescriptor::operator!=):
>+        (JSC::DFG::PromotedLocationDescriptor::isHashTableDeletedValue):
>+        (JSC::DFG::PromotedHeapLocation::PromotedHeapLocation):
>+        (JSC::DFG::PromotedHeapLocation::operator!):
>+        (JSC::DFG::PromotedHeapLocation::kind):
>+        (JSC::DFG::PromotedHeapLocation::base):
>+        (JSC::DFG::PromotedHeapLocation::info):
>+        (JSC::DFG::PromotedHeapLocation::descriptor):
>+        (JSC::DFG::PromotedHeapLocation::hash):
>+        (JSC::DFG::PromotedHeapLocation::operator==):
>+        (JSC::DFG::PromotedHeapLocation::isHashTableDeletedValue):
>+        (JSC::DFG::PromotedHeapLocationHash::hash):
>+        (JSC::DFG::PromotedHeapLocationHash::equal):
>+        * dfg/DFGSSACalculator.cpp:
>+        (JSC::DFG::SSACalculator::reset):
>+        * dfg/DFGSSACalculator.h:
>+        * dfg/DFGSafeToExecute.h:
>+        (JSC::DFG::safeToExecute):
>+        * dfg/DFGSpeculativeJIT.cpp:
>+        (JSC::DFG::SpeculativeJIT::compileCurrentBlock):
>+        * dfg/DFGSpeculativeJIT32_64.cpp:
>+        (JSC::DFG::SpeculativeJIT::compile):
>+        * dfg/DFGSpeculativeJIT64.cpp:
>+        (JSC::DFG::SpeculativeJIT::compile):
>+        * dfg/DFGStructureRegistrationPhase.cpp:
>+        (JSC::DFG::StructureRegistrationPhase::run):
>+        * dfg/DFGValidate.cpp:
>+        (JSC::DFG::Validate::validate):
>+        * ftl/FTLCapabilities.cpp:
>+        (JSC::FTL::canCompile):
>+        * ftl/FTLExitPropertyValue.cpp: Added.
>+        (JSC::FTL::ExitPropertyValue::dump):
>+        * ftl/FTLExitPropertyValue.h: Added.
>+        (JSC::FTL::ExitPropertyValue::ExitPropertyValue):
>+        (JSC::FTL::ExitPropertyValue::operator!):
>+        (JSC::FTL::ExitPropertyValue::location):
>+        (JSC::FTL::ExitPropertyValue::value):
>+        * ftl/FTLExitTimeObjectMaterialization.cpp: Added.
>+        (JSC::FTL::ExitTimeObjectMaterialization::ExitTimeObjectMaterialization):
>+        (JSC::FTL::ExitTimeObjectMaterialization::~ExitTimeObjectMaterialization):
>+        (JSC::FTL::ExitTimeObjectMaterialization::add):
>+        (JSC::FTL::ExitTimeObjectMaterialization::get):
>+        (JSC::FTL::ExitTimeObjectMaterialization::dump):
>+        * ftl/FTLExitTimeObjectMaterialization.h: Added.
>+        (JSC::FTL::ExitTimeObjectMaterialization::type):
>+        (JSC::FTL::ExitTimeObjectMaterialization::properties):
>+        * ftl/FTLExitValue.cpp:
>+        (JSC::FTL::ExitValue::materializeNewObject):
>+        (JSC::FTL::ExitValue::dumpInContext):
>+        * ftl/FTLExitValue.h:
>+        (JSC::FTL::ExitValue::isObjectMaterialization):
>+        (JSC::FTL::ExitValue::objectMaterialization):
>+        (JSC::FTL::ExitValue::withVirtualRegister):
>+        (JSC::FTL::ExitValue::valueFormat):
>+        * ftl/FTLLowerDFGToLLVM.cpp:
>+        (JSC::FTL::LowerDFGToLLVM::compileNode):
>+        (JSC::FTL::LowerDFGToLLVM::compileCheckStructure):
>+        (JSC::FTL::LowerDFGToLLVM::compileArrayifyToStructure):
>+        (JSC::FTL::LowerDFGToLLVM::compilePutStructure):
>+        (JSC::FTL::LowerDFGToLLVM::compileNewObject):
>+        (JSC::FTL::LowerDFGToLLVM::compileMultiGetByOffset):
>+        (JSC::FTL::LowerDFGToLLVM::compileMultiPutByOffset):
>+        (JSC::FTL::LowerDFGToLLVM::compileInvalidationPoint):
>+        (JSC::FTL::LowerDFGToLLVM::compileCheckStructureImmediate):
>+        (JSC::FTL::LowerDFGToLLVM::compileMaterializeNewObject):
>+        (JSC::FTL::LowerDFGToLLVM::checkStructure):
>+        (JSC::FTL::LowerDFGToLLVM::allocateCell):
>+        (JSC::FTL::LowerDFGToLLVM::storeStructure):
>+        (JSC::FTL::LowerDFGToLLVM::allocateObject):
>+        (JSC::FTL::LowerDFGToLLVM::speculateStringObjectForStructureID):
>+        (JSC::FTL::LowerDFGToLLVM::appendOSRExit):
>+        (JSC::FTL::LowerDFGToLLVM::buildExitArguments):
>+        (JSC::FTL::LowerDFGToLLVM::exitValueForAvailability):
>+        (JSC::FTL::LowerDFGToLLVM::exitValueForNode):
>+        (JSC::FTL::LowerDFGToLLVM::weakStructureID):
>+        (JSC::FTL::LowerDFGToLLVM::weakStructure):
>+        (JSC::FTL::LowerDFGToLLVM::availabilityMap):
>+        (JSC::FTL::LowerDFGToLLVM::availability): Deleted.
>+        * ftl/FTLOSRExit.h:
>+        * ftl/FTLOSRExitCompiler.cpp:
>+        (JSC::FTL::compileRecovery):
>+        (JSC::FTL::compileStub):
>+        * ftl/FTLOperations.cpp: Added.
>+        (JSC::FTL::operationNewObjectWithButterfly):
>+        (JSC::FTL::operationMaterializeObjectInOSR):
>+        * ftl/FTLOperations.h: Added.
>+        * ftl/FTLSwitchCase.h:
>+        (JSC::FTL::SwitchCase::SwitchCase):
>+        * runtime/JSObject.h:
>+        (JSC::JSObject::finishCreation):
>+        (JSC::JSFinalObject::JSFinalObject):
>+        (JSC::JSFinalObject::create):
>+        * runtime/Structure.cpp:
>+        (JSC::Structure::canUseForAllocationsOf):
>+        * runtime/Structure.h:
>+        * tests/stress/obviously-elidable-new-object-then-exit.js: Added.
>+        (sumOfArithSeries):
>+        (foo):
>+
> 2014-09-25  Csaba OsztrogonÃ¡c  <ossy@webkit.org>
> 
>         Remove WinCE port from trunk
>Index: Source/JavaScriptCore/CMakeLists.txt
>===================================================================
>--- Source/JavaScriptCore/CMakeLists.txt	(revision 173938)
>+++ Source/JavaScriptCore/CMakeLists.txt	(working copy)
>@@ -122,6 +122,7 @@ set(JavaScriptCore_SOURCES
>     dfg/DFGArrayMode.cpp
>     dfg/DFGAtTailAbstractState.cpp
>     dfg/DFGAvailability.cpp
>+    dfg/DFGAvailabilityMap.cpp
>     dfg/DFGBackwardsPropagationPhase.cpp
>     dfg/DFGBasicBlock.cpp
>     dfg/DFGBinarySwitch.cpp
>@@ -164,6 +165,7 @@ set(JavaScriptCore_SOURCES
>     dfg/DFGGraphSafepoint.cpp
>     dfg/DFGHeapLocation.cpp
>     dfg/DFGInPlaceAbstractState.cpp
>+    dfg/DFGInsertOSRHintsForUpdate.cpp
>     dfg/DFGIntegerCheckCombiningPhase.cpp
>     dfg/DFGInvalidationPointInjectionPhase.cpp
>     dfg/DFGJITCode.cpp
>@@ -192,13 +194,18 @@ set(JavaScriptCore_SOURCES
>     dfg/DFGOSRExitCompilerCommon.cpp
>     dfg/DFGOSRExitJumpPlaceholder.cpp
>     dfg/DFGOSRExitPreparation.cpp
>+    dfg/DFGObjectAllocationSinkingPhase.cpp
>+    dfg/DFGObjectMaterializationData.cpp
>     dfg/DFGOperations.cpp
>     dfg/DFGPhantomCanonicalizationPhase.cpp
>     dfg/DFGPhantomRemovalPhase.cpp
>     dfg/DFGPhase.cpp
>+    dfg/DFGPhiChildren.cpp
>     dfg/DFGPlan.cpp
>+    dfg/DFGPrePostNumbering.cpp
>     dfg/DFGPredictionInjectionPhase.cpp
>     dfg/DFGPredictionPropagationPhase.cpp
>+    dfg/DFGPromotedHeapLocation.cpp
>     dfg/DFGPureValue.cpp
>     dfg/DFGResurrectionForValidationPhase.cpp
>     dfg/DFGSSACalculator.cpp
>@@ -774,7 +781,9 @@ if (ENABLE_FTL_JIT)
>         ftl/FTLDataSection.cpp
>         ftl/FTLExitArgument.cpp
>         ftl/FTLExitArgumentForOperand.cpp
>+        ftl/FTLExitPropertyValue.cpp
>         ftl/FTLExitThunkGenerator.cpp
>+        ftl/FTLExitTimeObjectMaterialization.cpp
>         ftl/FTLExitValue.cpp
>         ftl/FTLFail.cpp
>         ftl/FTLForOSREntryJITCode.cpp
>@@ -789,6 +798,7 @@ if (ENABLE_FTL_JIT)
>         ftl/FTLOSREntry.cpp
>         ftl/FTLOSRExitCompiler.cpp
>         ftl/FTLOSRExit.cpp
>+        ftl/FTLOperations.cpp
>         ftl/FTLOutput.cpp
>         ftl/FTLRecoveryOpcode.cpp
>         ftl/FTLRegisterAtOffset.cpp
>Index: Source/JavaScriptCore/JavaScriptCore.vcxproj/JavaScriptCore.vcxproj
>===================================================================
>--- Source/JavaScriptCore/JavaScriptCore.vcxproj/JavaScriptCore.vcxproj	(revision 173938)
>+++ Source/JavaScriptCore/JavaScriptCore.vcxproj/JavaScriptCore.vcxproj	(working copy)
>@@ -1,4 +1,4 @@
>-ï»¿<?xml version="1.0" encoding="utf-8"?>
>+<?xml version="1.0" encoding="utf-8"?>
> <Project DefaultTargets="Build" ToolsVersion="12.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
>   <ItemGroup Label="ProjectConfigurations">
>     <ProjectConfiguration Include="DebugSuffix|Win32">
>@@ -368,6 +368,7 @@
>     <ClCompile Include="..\dfg\DFGArrayMode.cpp" />
>     <ClCompile Include="..\dfg\DFGAtTailAbstractState.cpp" />
>     <ClCompile Include="..\dfg\DFGAvailability.cpp" />
>+    <ClCompile Include="..\dfg\DFGAvailabilityMap.cpp" />
>     <ClCompile Include="..\dfg\DFGBackwardsPropagationPhase.cpp" />
>     <ClCompile Include="..\dfg\DFGBasicBlock.cpp" />
>     <ClCompile Include="..\dfg\DFGBinarySwitch.cpp" />
>@@ -410,6 +411,7 @@
>     <ClCompile Include="..\dfg\DFGGraphSafepoint.cpp" />
>     <ClCompile Include="..\dfg\DFGHeapLocation.cpp" />
>     <ClCompile Include="..\dfg\DFGInPlaceAbstractState.cpp" />
>+    <ClCompile Include="..\dfg\DFGInsertOSRHintsForUpdate.cpp" />
>     <ClCompile Include="..\dfg\DFGIntegerCheckCombiningPhase.cpp" />
>     <ClCompile Include="..\dfg\DFGInvalidationPointInjectionPhase.cpp" />
>     <ClCompile Include="..\dfg\DFGJITCode.cpp" />
>@@ -439,12 +441,17 @@
>     <ClCompile Include="..\dfg\DFGOSRExitCompilerCommon.cpp" />
>     <ClCompile Include="..\dfg\DFGOSRExitJumpPlaceholder.cpp" />
>     <ClCompile Include="..\dfg\DFGOSRExitPreparation.cpp" />
>+    <ClCompile Include="..\dfg\DFGObjectAllocationSinkingPhase.cpp" />
>+    <ClCompile Include="..\dfg\DFGObjectMaterializationData.cpp" />
>     <ClCompile Include="..\dfg\DFGPhantomCanonicalizationPhase.cpp" />
>     <ClCompile Include="..\dfg\DFGPhantomRemovalPhase.cpp" />
>     <ClCompile Include="..\dfg\DFGPhase.cpp" />
>+    <ClCompile Include="..\dfg\DFGPhiChildren.cpp" />
>     <ClCompile Include="..\dfg\DFGPlan.cpp" />
>+    <ClCompile Include="..\dfg\DFGPrePostNumbering.cpp" />
>     <ClCompile Include="..\dfg\DFGPredictionInjectionPhase.cpp" />
>     <ClCompile Include="..\dfg\DFGPredictionPropagationPhase.cpp" />
>+    <ClCompile Include="..\dfg\DFGPromotedHeapLocation.cpp" />
>     <ClCompile Include="..\dfg\DFGPureValue.cpp" />
>     <ClCompile Include="..\dfg\DFGResurrectionForValidationPhase.cpp" />
>     <ClCompile Include="..\dfg\DFGSafepoint.cpp" />
>@@ -493,7 +500,9 @@
>     <ClCompile Include="..\ftl\FTLDWARFRegister.cpp" />
>     <ClCompile Include="..\ftl\FTLExitArgument.cpp" />
>     <ClCompile Include="..\ftl\FTLExitArgumentForOperand.cpp" />
>+    <ClCompile Include="..\ftl\FTLExitPropertyValue.cpp" />
>     <ClCompile Include="..\ftl\FTLExitThunkGenerator.cpp" />
>+    <ClCompile Include="..\ftl\FTLExitTimeObjectMaterialization.cpp" />
>     <ClCompile Include="..\ftl\FTLExitValue.cpp" />
>     <ClCompile Include="..\ftl\FTLFail.cpp" />
>     <ClCompile Include="..\ftl\FTLForOSREntryJITCode.cpp" />
>@@ -508,6 +517,7 @@
>     <ClCompile Include="..\ftl\FTLOSREntry.cpp" />
>     <ClCompile Include="..\ftl\FTLOSRExit.cpp" />
>     <ClCompile Include="..\ftl\FTLOSRExitCompiler.cpp" />
>+    <ClCompile Include="..\ftl\FTLOperations.cpp" />
>     <ClCompile Include="..\ftl\FTLOutput.cpp" />
>     <ClCompile Include="..\ftl\FTLRecoveryOpcode.cpp" />
>     <ClCompile Include="..\ftl\FTLRegisterAtOffset.cpp" />
>@@ -993,6 +1003,7 @@
>     <ClInclude Include="..\dfg\DFGArrayMode.h" />
>     <ClInclude Include="..\dfg\DFGAtTailAbstractState.h" />
>     <ClInclude Include="..\dfg\DFGAvailability.h" />
>+    <ClInclude Include="..\dfg\DFGAvailabilityMap.h" />
>     <ClInclude Include="..\dfg\DFGBackwardsPropagationPhase.h" />
>     <ClInclude Include="..\dfg\DFGBasicBlock.h" />
>     <ClInclude Include="..\dfg\DFGBasicBlockInlines.h" />
>@@ -1049,6 +1060,7 @@
>     <ClInclude Include="..\dfg\DFGGraphSafepoint.h" />
>     <ClInclude Include="..\dfg\DFGHeapLocation.h" />
>     <ClInclude Include="..\dfg\DFGInPlaceAbstractState.h" />
>+    <ClInclude Include="..\dfg\DFGInsertOSRHintsForUpdate.h" />
>     <ClInclude Include="..\dfg\DFGInsertionSet.h" />
>     <ClInclude Include="..\dfg\DFGIntegerCheckCombiningPhase.h" />
>     <ClInclude Include="..\dfg\DFGInvalidationPointInjectionPhase.h" />
>@@ -1073,6 +1085,8 @@
>     <ClInclude Include="..\dfg\DFGNodeFlags.h" />
>     <ClInclude Include="..\dfg\DFGNodeOrigin.h" />
>     <ClInclude Include="..\dfg\DFGNodeType.h" />
>+    <ClInclude Include="..\dfg\DFGObjectAllocationSinkingPhase.h" />
>+    <ClInclude Include="..\dfg\DFGObjectMaterializationData.h" />
>     <ClInclude Include="..\dfg\DFGOperations.h" />
>     <ClInclude Include="..\dfg\DFGOSRAvailabilityAnalysisPhase.h" />
>     <ClInclude Include="..\dfg\DFGOSREntry.h" />
>@@ -1087,9 +1101,13 @@
>     <ClInclude Include="..\dfg\DFGPhantomCanonicalizationPhase.h" />
>     <ClInclude Include="..\dfg\DFGPhantomRemovalPhase.h" />
>     <ClInclude Include="..\dfg\DFGPhase.h" />
>+    <ClInclude Include="..\dfg\DFGPhiChildren.h" />
>     <ClInclude Include="..\dfg\DFGPlan.h" />
>+    <ClInclude Include="..\dfg\DFGPrePostNumbering.h" />
>     <ClInclude Include="..\dfg\DFGPredictionInjectionPhase.h" />
>     <ClInclude Include="..\dfg\DFGPredictionPropagationPhase.h" />
>+    <ClInclude Include="..\dfg\DFGPromoteHeapAccess.h" />
>+    <ClInclude Include="..\dfg\DFGPromotedHeapLocation.h" />
>     <ClInclude Include="..\dfg\DFGPureValue.h" />
>     <ClInclude Include="..\dfg\DFGRegisterBank.h" />
>     <ClInclude Include="..\dfg\DFGRegisterSet.h" />
>@@ -1150,7 +1168,9 @@
>     <ClInclude Include="..\ftl\FTLExitArgument.h" />
>     <ClInclude Include="..\ftl\FTLExitArgumentForOperand.h" />
>     <ClInclude Include="..\ftl\FTLExitArgumentList.h" />
>+    <ClInclude Include="..\ftl\FTLExitPropertyValue.h" />
>     <ClInclude Include="..\ftl\FTLExitThunkGenerator.h" />
>+    <ClInclude Include="..\ftl\FTLExitTimeObjectMaterialization.h" />
>     <ClInclude Include="..\ftl\FTLExitValue.h" />
>     <ClInclude Include="..\ftl\FTLFail.h" />
>     <ClInclude Include="..\ftl\FTLFormattedValue.h" />
>@@ -1170,6 +1190,7 @@
>     <ClInclude Include="..\ftl\FTLOSRExit.h" />
>     <ClInclude Include="..\ftl\FTLOSRExitCompilationInfo.h" />
>     <ClInclude Include="..\ftl\FTLOSRExitCompiler.h" />
>+    <ClInclude Include="..\ftl\FTLOperations.h" />
>     <ClInclude Include="..\ftl\FTLOutput.h" />
>     <ClInclude Include="..\ftl\FTLRecoveryOpcode.h" />
>     <ClInclude Include="..\ftl\FTLRegisterAtOffset.h" />
>Index: Source/JavaScriptCore/JavaScriptCore.xcodeproj/project.pbxproj
>===================================================================
>--- Source/JavaScriptCore/JavaScriptCore.xcodeproj/project.pbxproj	(revision 173938)
>+++ Source/JavaScriptCore/JavaScriptCore.xcodeproj/project.pbxproj	(working copy)
>@@ -209,6 +209,24 @@
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>+		0F2B9CE619D0BA7D00B1D1B5 /* DFGObjectAllocationSinkingPhase.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 0F2B9CDA19D0BA7D00B1D1B5 /* DFGObjectAllocationSinkingPhase.cpp */; };
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>+		0F2B9CE819D0BA7D00B1D1B5 /* DFGObjectMaterializationData.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 0F2B9CDC19D0BA7D00B1D1B5 /* DFGObjectMaterializationData.cpp */; };
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>+		0F2B9CF419D0BAC100B1D1B5 /* FTLExitPropertyValue.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 0F2B9CEE19D0BAC100B1D1B5 /* FTLExitPropertyValue.cpp */; };
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>+		0F2B9CF819D0BAC100B1D1B5 /* FTLOperations.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 0F2B9CF219D0BAC100B1D1B5 /* FTLOperations.cpp */; };
>+		0F2B9CF919D0BAC100B1D1B5 /* FTLOperations.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F2B9CF319D0BAC100B1D1B5 /* FTLOperations.h */; settings = {ATTRIBUTES = (Private, ); }; };
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>@@ -272,6 +290,8 @@
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>+		0F3E01AA19D353A500F61B7F /* DFGPrePostNumbering.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 0F3E01A819D353A500F61B7F /* DFGPrePostNumbering.cpp */; };
>+		0F3E01AB19D353A500F61B7F /* DFGPrePostNumbering.h in Headers */ = {isa = PBXBuildFile; fileRef = 0F3E01A919D353A500F61B7F /* DFGPrePostNumbering.h */; settings = {ATTRIBUTES = (Private, ); }; };
> 		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, ); }; };
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>@@ -443,6 +463,7 @@
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> 		0FA7A8EC18B413C80052371D /* Reg.h in Headers */ = {isa = PBXBuildFile; fileRef = 0FA7A8EA18B413C80052371D /* Reg.h */; settings = {ATTRIBUTES = (Private, ); }; };
> 		0FA7A8EE18CE4FD80052371D /* ScratchRegisterAllocator.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 0FA7A8ED18CE4FD80052371D /* ScratchRegisterAllocator.cpp */; };
>+		0FAA3E0919D0C2CB00FAC9E2 /* DFGPromoteHeapAccess.h in Headers */ = {isa = PBXBuildFile; fileRef = 0FAA3E0819D0C2CB00FAC9E2 /* DFGPromoteHeapAccess.h */; settings = {ATTRIBUTES = (Private, ); }; };
> 		0FAF7EFD165BA91B000C8455 /* JITDisassembler.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 0FAF7EFA165BA919000C8455 /* JITDisassembler.cpp */; };
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>@@ -1831,6 +1852,24 @@
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>@@ -1892,6 +1931,8 @@
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> 		0F426A461460CBAB00131F8F /* VirtualRegister.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = VirtualRegister.h; sourceTree = "<group>"; };
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>@@ -2062,6 +2103,7 @@
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> 		0FA7A8EA18B413C80052371D /* Reg.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = Reg.h; sourceTree = "<group>"; };
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>@@ -3471,8 +3513,12 @@
> 				0F235BBF17178E1C00690C7F /* FTLExitArgumentForOperand.cpp */,
> 				0F235BC017178E1C00690C7F /* FTLExitArgumentForOperand.h */,
> 				0F235BC117178E1C00690C7F /* FTLExitArgumentList.h */,
>+				0F2B9CEE19D0BAC100B1D1B5 /* FTLExitPropertyValue.cpp */,
>+				0F2B9CEF19D0BAC100B1D1B5 /* FTLExitPropertyValue.h */,
> 				0F235BC217178E1C00690C7F /* FTLExitThunkGenerator.cpp */,
> 				0F235BC317178E1C00690C7F /* FTLExitThunkGenerator.h */,
>+				0F2B9CF019D0BAC100B1D1B5 /* FTLExitTimeObjectMaterialization.cpp */,
>+				0F2B9CF119D0BAC100B1D1B5 /* FTLExitTimeObjectMaterialization.h */,
> 				0F235BC417178E1C00690C7F /* FTLExitValue.cpp */,
> 				0F235BC517178E1C00690C7F /* FTLExitValue.h */,
> 				A7F2996917A0BB670010417A /* FTLFail.cpp */,
>@@ -3499,6 +3545,8 @@
> 				0FEA0A04170513DB00BB722C /* FTLLowerDFGToLLVM.cpp */,
> 				0FEA0A05170513DB00BB722C /* FTLLowerDFGToLLVM.h */,
> 				A7D89D0117A0B90400773AD8 /* FTLLoweredNodeValue.h */,
>+				0F2B9CF219D0BAC100B1D1B5 /* FTLOperations.cpp */,
>+				0F2B9CF319D0BAC100B1D1B5 /* FTLOperations.h */,
> 				0FD8A31717D51F2200CA2C40 /* FTLOSREntry.cpp */,
> 				0FD8A31817D51F2200CA2C40 /* FTLOSREntry.h */,
> 				0F235BC617178E1C00690C7F /* FTLOSRExit.cpp */,
>@@ -4528,6 +4576,8 @@
> 				A7D9A29017A0BC7400EE2618 /* DFGAtTailAbstractState.h */,
> 				0F666EC21835672B00D017F1 /* DFGAvailability.cpp */,
> 				0F666EC31835672B00D017F1 /* DFGAvailability.h */,
>+				0F2B9CD619D0BA7D00B1D1B5 /* DFGAvailabilityMap.cpp */,
>+				0F2B9CD719D0BA7D00B1D1B5 /* DFGAvailabilityMap.h */,
> 				0F714CA116EA92ED00F3EBEB /* DFGBackwardsPropagationPhase.cpp */,
> 				0F714CA216EA92ED00F3EBEB /* DFGBackwardsPropagationPhase.h */,
> 				A7D89CE317A0B8CC00773AD8 /* DFGBasicBlock.cpp */,
>@@ -4626,6 +4676,8 @@
> 				A704D90017A0BAA8006BA554 /* DFGInPlaceAbstractState.cpp */,
> 				A704D90117A0BAA8006BA554 /* DFGInPlaceAbstractState.h */,
> 				0F2BDC1F151E803800CD8910 /* DFGInsertionSet.h */,
>+				0F2B9CD819D0BA7D00B1D1B5 /* DFGInsertOSRHintsForUpdate.cpp */,
>+				0F2B9CD919D0BA7D00B1D1B5 /* DFGInsertOSRHintsForUpdate.h */,
> 				0F300B7918AB1B1400A6D72E /* DFGIntegerCheckCombiningPhase.cpp */,
> 				0F300B7A18AB1B1400A6D72E /* DFGIntegerCheckCombiningPhase.h */,
> 				0FC97F3718202119002C9B26 /* DFGInvalidationPointInjectionPhase.cpp */,
>@@ -4666,6 +4718,10 @@
> 				0FA581B8150E952A00B9A2D9 /* DFGNodeFlags.h */,
> 				0F300B7718AB051100A6D72E /* DFGNodeOrigin.h */,
> 				0FA581B9150E952A00B9A2D9 /* DFGNodeType.h */,
>+				0F2B9CDA19D0BA7D00B1D1B5 /* DFGObjectAllocationSinkingPhase.cpp */,
>+				0F2B9CDB19D0BA7D00B1D1B5 /* DFGObjectAllocationSinkingPhase.h */,
>+				0F2B9CDC19D0BA7D00B1D1B5 /* DFGObjectMaterializationData.cpp */,
>+				0F2B9CDD19D0BA7D00B1D1B5 /* DFGObjectMaterializationData.h */,
> 				86EC9DBF1328DF82002B2AD7 /* DFGOperations.cpp */,
> 				86EC9DC01328DF82002B2AD7 /* DFGOperations.h */,
> 				A7D89CEE17A0B8CC00773AD8 /* DFGOSRAvailabilityAnalysisPhase.cpp */,
>@@ -4695,12 +4751,19 @@
> 				0FBFDD03196C92BF007A5BFA /* DFGPhantomRemovalPhase.h */,
> 				0FFFC94F14EF909500C72532 /* DFGPhase.cpp */,
> 				0FFFC95014EF909500C72532 /* DFGPhase.h */,
>+				0F2B9CDE19D0BA7D00B1D1B5 /* DFGPhiChildren.cpp */,
>+				0F2B9CDF19D0BA7D00B1D1B5 /* DFGPhiChildren.h */,
> 				A78A9772179738B8009DF744 /* DFGPlan.cpp */,
> 				A78A9773179738B8009DF744 /* DFGPlan.h */,
> 				0FBE0F6D16C1DB010082C5E8 /* DFGPredictionInjectionPhase.cpp */,
> 				0FBE0F6E16C1DB010082C5E8 /* DFGPredictionInjectionPhase.h */,
> 				0FFFC95114EF909500C72532 /* DFGPredictionPropagationPhase.cpp */,
> 				0FFFC95214EF909500C72532 /* DFGPredictionPropagationPhase.h */,
>+				0F3E01A819D353A500F61B7F /* DFGPrePostNumbering.cpp */,
>+				0F3E01A919D353A500F61B7F /* DFGPrePostNumbering.h */,
>+				0F2B9CE019D0BA7D00B1D1B5 /* DFGPromotedHeapLocation.cpp */,
>+				0F2B9CE119D0BA7D00B1D1B5 /* DFGPromotedHeapLocation.h */,
>+				0FAA3E0819D0C2CB00FAC9E2 /* DFGPromoteHeapAccess.h */,
> 				0FB1765E196B8F9E0091052A /* DFGPureValue.cpp */,
> 				0FB1765F196B8F9E0091052A /* DFGPureValue.h */,
> 				86EC9DC11328DF82002B2AD7 /* DFGRegisterBank.h */,
>@@ -5281,6 +5344,7 @@
> 				A5D2E665195E174000A518E7 /* JSContextRefInternal.h in Headers */,
> 				A7D801A51880D66E0026C39B /* BuiltinExecutables.h in Headers */,
> 				A75EE9B218AAB7E200AAD043 /* BuiltinNames.h in Headers */,
>+				0F2B9CF719D0BAC100B1D1B5 /* FTLExitTimeObjectMaterialization.h in Headers */,
> 				0FB7F39715ED8E4600F167B2 /* Butterfly.h in Headers */,
> 				0FB7F39815ED8E4600F167B2 /* ButterflyInlines.h in Headers */,
> 				C2FCAE1117A9C24E0034C735 /* BytecodeBasicBlock.h in Headers */,
>@@ -5339,6 +5403,7 @@
> 				2A68295B1875F80500B6C3E2 /* CopyWriteBarrier.h in Headers */,
> 				5DE6E5B30E1728EC00180407 /* create_hash_table in Headers */,
> 				0F426A4B1460CD6E00131F8F /* DataFormat.h in Headers */,
>+				0F2B9CE519D0BA7D00B1D1B5 /* DFGInsertOSRHintsForUpdate.h in Headers */,
> 				0F2B66DF17B6B5AB00A7AE3F /* DataView.h in Headers */,
> 				BCD2034A0E17135E002C7E82 /* DateConstructor.h in Headers */,
> 				41359CF30FDD89AD00206180 /* DateConversion.h in Headers */,
>@@ -5426,10 +5491,12 @@
> 				A78A9779179738B8009DF744 /* DFGJITFinalizer.h in Headers */,
> 				0FC97F4018202119002C9B26 /* DFGJumpReplacement.h in Headers */,
> 				A73A535B1799CD5D00170C19 /* DFGLazyJSValue.h in Headers */,
>+				0F2B9CE919D0BA7D00B1D1B5 /* DFGObjectMaterializationData.h in Headers */,
> 				A7D9A29817A0BC7400EE2618 /* DFGLICMPhase.h in Headers */,
> 				A7D89CFC17A0B8CC00773AD8 /* DFGLivenessAnalysisPhase.h in Headers */,
> 				0FF0F19B16B729FA005DF95B /* DFGLongLivedState.h in Headers */,
> 				A767B5B617A0B9650063D940 /* DFGLoopPreHeaderCreationPhase.h in Headers */,
>+				0F2B9CED19D0BA7D00B1D1B5 /* DFGPromotedHeapLocation.h in Headers */,
> 				A704D90717A0BAA8006BA554 /* DFGMergeMode.h in Headers */,
> 				0FB17663196B8F9E0091052A /* DFGPureValue.h in Headers */,
> 				0F2BDC451522801B00CD8910 /* DFGMinifiedGraph.h in Headers */,
>@@ -5486,6 +5553,7 @@
> 				0F2BDC471522802500CD8910 /* DFGValueRecoveryOverride.h in Headers */,
> 				0F2BDC481522802900CD8910 /* DFGValueSource.h in Headers */,
> 				0F620174143FCD330068B77C /* DFGVariableAccessData.h in Headers */,
>+				0FAA3E0919D0C2CB00FAC9E2 /* DFGPromoteHeapAccess.h in Headers */,
> 				0FDDBFB61666EEDA00C55FEF /* DFGVariableAccessDataDump.h in Headers */,
> 				0F2BDC491522809600CD8910 /* DFGVariableEvent.h in Headers */,
> 				0F2BDC4B1522809D00CD8910 /* DFGVariableEventStream.h in Headers */,
>@@ -5623,6 +5691,7 @@
> 				0F24E55617F0B71C00ABB217 /* InlineCallFrameSet.h in Headers */,
> 				99E45A2718A1B2590026D88F /* InputCursor.h in Headers */,
> 				A593CF7F1840362C00BFCE27 /* InspectorAgentBase.h in Headers */,
>+				0F3E01AB19D353A500F61B7F /* DFGPrePostNumbering.h in Headers */,
> 				A593CF87184038CA00BFCE27 /* InspectorAgentRegistry.h in Headers */,
> 				A593CF7D1840360300BFCE27 /* InspectorBackendDispatcher.h in Headers */,
> 				A5FD0082189B191A00633231 /* InspectorConsoleAgent.h in Headers */,
>@@ -5647,6 +5716,7 @@
> 				1429D77C0ED20D7300B89619 /* Interpreter.h in Headers */,
> 				860BD801148EA6F200112B2F /* Intrinsic.h in Headers */,
> 				BC18C4130E16F5CD00B34460 /* JavaScript.h in Headers */,
>+				0F2B9CF519D0BAC100B1D1B5 /* FTLExitPropertyValue.h in Headers */,
> 				A503FA1A188E0FB000110F14 /* JavaScriptCallFrame.h in Headers */,
> 				BC18C4140E16F5CD00B34460 /* JavaScriptCore.h in Headers */,
> 				BC18C4150E16F5CD00B34460 /* JavaScriptCorePrefix.h in Headers */,
>@@ -5690,6 +5760,7 @@
> 				657CF45919BF6662004ACBF2 /* JSCallee.h in Headers */,
> 				BC18C4190E16F5CD00B34460 /* JSCallbackConstructor.h in Headers */,
> 				BC18C41A0E16F5CD00B34460 /* JSCallbackFunction.h in Headers */,
>+				0F2B9CF919D0BAC100B1D1B5 /* FTLOperations.h in Headers */,
> 				BC18C41B0E16F5CD00B34460 /* JSCallbackObject.h in Headers */,
> 				BC18C41C0E16F5CD00B34460 /* JSCallbackObjectFunctions.h in Headers */,
> 				A7D801A91880D6A80026C39B /* JSCBuiltins.h in Headers */,
>@@ -5790,6 +5861,7 @@
> 				BC18C42D0E16F5CD00B34460 /* JSEnvironmentRecord.h in Headers */,
> 				86E3C615167BABD7006D760A /* JSVirtualMachine.h in Headers */,
> 				86E3C61D167BABEE006D760A /* JSVirtualMachineInternal.h in Headers */,
>+				0F2B9CE719D0BA7D00B1D1B5 /* DFGObjectAllocationSinkingPhase.h in Headers */,
> 				A7CA3AE817DA41AE006538AF /* JSWeakMap.h in Headers */,
> 				A7482E93116A7CAD003B0712 /* JSWeakObjectMapRefInternal.h in Headers */,
> 				A7482B9311671147003B0712 /* JSWeakObjectMapRefPrivate.h in Headers */,
>@@ -5904,6 +5976,7 @@
> 				0F13912A16771C36009CCB07 /* ProfilerBytecodeSequence.h in Headers */,
> 				0FF729BA166AD360000F5BA3 /* ProfilerCompilation.h in Headers */,
> 				0FF729BB166AD360000F5BA3 /* ProfilerCompilationKind.h in Headers */,
>+				0F2B9CE319D0BA7D00B1D1B5 /* DFGAvailabilityMap.h in Headers */,
> 				0FF729BC166AD360000F5BA3 /* ProfilerCompiledBytecode.h in Headers */,
> 				0FF729BD166AD360000F5BA3 /* ProfilerDatabase.h in Headers */,
> 				2A05ABD61961DF2400341750 /* JSPropertyNameEnumerator.h in Headers */,
>@@ -6011,6 +6084,7 @@
> 				0FD2C92416D01EE900C7803F /* StructureInlines.h in Headers */,
> 				C2FE18A416BAEC4000AF3061 /* StructureRareData.h in Headers */,
> 				C20BA92D16BB1C1500B3AEA2 /* StructureRareDataInlines.h in Headers */,
>+				0F2B9CEB19D0BA7D00B1D1B5 /* DFGPhiChildren.h in Headers */,
> 				0F9332A514CA7DDD0085F3C6 /* StructureSet.h in Headers */,
> 				0F766D3915AE4A1F008F363E /* StructureStubClearingWatchpoint.h in Headers */,
> 				BCCF0D080EF0AAB900413C8F /* StructureStubInfo.h in Headers */,
>@@ -6579,6 +6653,7 @@
> 				1429D8DD0ED2205B00B89619 /* CallFrame.cpp in Sources */,
> 				0F0B83B014BCF71600885B4F /* CallLinkInfo.cpp in Sources */,
> 				0F93329D14CA7DC30085F3C6 /* CallLinkStatus.cpp in Sources */,
>+				0F2B9CE419D0BA7D00B1D1B5 /* DFGInsertOSRHintsForUpdate.cpp in Sources */,
> 				0F73D7AE165A142D00ACAB71 /* ClosureCallStubRoutine.cpp in Sources */,
> 				969A07960ED1D3AE00F1F681 /* CodeBlock.cpp in Sources */,
> 				0F8F94401667633000D61971 /* CodeBlockHash.cpp in Sources */,
>@@ -6623,12 +6698,14 @@
> 				A7D9A29417A0BC7400EE2618 /* DFGAtTailAbstractState.cpp in Sources */,
> 				0F666EC61835672B00D017F1 /* DFGAvailability.cpp in Sources */,
> 				0F714CA416EA92F000F3EBEB /* DFGBackwardsPropagationPhase.cpp in Sources */,
>+				0F2B9CEC19D0BA7D00B1D1B5 /* DFGPromotedHeapLocation.cpp in Sources */,
> 				A7D89CF217A0B8CC00773AD8 /* DFGBasicBlock.cpp in Sources */,
> 				A70B083217A0B79B00DAF14B /* DFGBinarySwitch.cpp in Sources */,
> 				2A88067819107D5500CB0BBB /* DFGFunctionWhitelist.cpp in Sources */,
> 				A7D89CF317A0B8CC00773AD8 /* DFGBlockInsertionSet.cpp in Sources */,
> 				86EC9DC41328DF82002B2AD7 /* DFGByteCodeParser.cpp in Sources */,
> 				0FD82E2114172CE300179C94 /* DFGCapabilities.cpp in Sources */,
>+				0F2B9CE619D0BA7D00B1D1B5 /* DFGObjectAllocationSinkingPhase.cpp in Sources */,
> 				0FFFC95714EF90A000C72532 /* DFGCFAPhase.cpp in Sources */,
> 				0F3B3A271544C995003ED0FF /* DFGCFGSimplificationPhase.cpp in Sources */,
> 				A77A423F17A0BBFD00A8DB81 /* DFGClobberize.cpp in Sources */,
>@@ -6651,6 +6728,8 @@
> 				0FCA9113195E66A000426438 /* VariableWatchpointSet.cpp in Sources */,
> 				0FD81AD2154FB4EE00983E72 /* DFGDominators.cpp in Sources */,
> 				0FD3C82614115D4000FD81CB /* DFGDriver.cpp in Sources */,
>+				0F2B9CE219D0BA7D00B1D1B5 /* DFGAvailabilityMap.cpp in Sources */,
>+				0F2B9CE819D0BA7D00B1D1B5 /* DFGObjectMaterializationData.cpp in Sources */,
> 				0FF0F19E16B72A0B005DF95B /* DFGEdge.cpp in Sources */,
> 				0FBC0AE71496C7C400D4FBDD /* DFGExitProfile.cpp in Sources */,
> 				0F0123321944EA1B00843A0C /* DFGValueStrength.cpp in Sources */,
>@@ -6767,6 +6846,7 @@
> 				0FC3CCFF19ADA410006AC72A /* DFGBlockWorklist.cpp in Sources */,
> 				0FEA0A0D170513DB00BB722C /* FTLJITCode.cpp in Sources */,
> 				A78A9780179738D5009DF744 /* FTLJITFinalizer.cpp in Sources */,
>+				0F2B9CF419D0BAC100B1D1B5 /* FTLExitPropertyValue.cpp in Sources */,
> 				0F6B1CB5185FC9E900845D97 /* FTLJSCall.cpp in Sources */,
> 				0F8F2B95172E04A0007DBDA5 /* FTLLink.cpp in Sources */,
> 				0FCEFADF180738C000472CE4 /* FTLLocation.cpp in Sources */,
>@@ -6818,6 +6898,7 @@
> 				0F24E55517F0B71C00ABB217 /* InlineCallFrameSet.cpp in Sources */,
> 				A5CEEE14187F3BAD00E55C99 /* InspectorAgent.cpp in Sources */,
> 				A593CF86184038CA00BFCE27 /* InspectorAgentRegistry.cpp in Sources */,
>+				0F2B9CF619D0BAC100B1D1B5 /* FTLExitTimeObjectMaterialization.cpp in Sources */,
> 				A593CF7C1840360300BFCE27 /* InspectorBackendDispatcher.cpp in Sources */,
> 				2AF7382C18BBBF92008A5A37 /* StructureIDTable.cpp in Sources */,
> 				A5FD0081189B191A00633231 /* InspectorConsoleAgent.cpp in Sources */,
>@@ -6997,6 +7078,7 @@
> 				0F9FC8C314E1B5FE00D52AE0 /* PolymorphicPutByIdList.cpp in Sources */,
> 				0F98206016BFE38100240D02 /* PreciseJumpTargets.cpp in Sources */,
> 				95742F650DD11F5A000917FB /* Profile.cpp in Sources */,
>+				0F2B9CF819D0BAC100B1D1B5 /* FTLOperations.cpp in Sources */,
> 				95CD45760E1C4FDD0085358E /* ProfileGenerator.cpp in Sources */,
> 				95AB83560DA43C3000BC83F3 /* ProfileNode.cpp in Sources */,
> 				0FF729AD166AD35C000F5BA3 /* ProfilerBytecode.cpp in Sources */,
>@@ -7019,6 +7101,7 @@
> 				65FB5117184EEE7000C12B70 /* ProtoCallFrame.cpp in Sources */,
> 				1474C33C16AA2D9B0062F01D /* PrototypeMap.cpp in Sources */,
> 				0F9332A314CA7DD70085F3C6 /* PutByIdStatus.cpp in Sources */,
>+				0F3E01AA19D353A500F61B7F /* DFGPrePostNumbering.cpp in Sources */,
> 				0FF60AC316740F8800029779 /* ReduceWhitespace.cpp in Sources */,
> 				0FA7A8EB18B413C80052371D /* Reg.cpp in Sources */,
> 				14280841107EC0930013E7B2 /* RegExp.cpp in Sources */,
>@@ -7088,6 +7171,7 @@
> 				0FF42745158EBE91004CB9FF /* udis86_syn-att.c in Sources */,
> 				0FF42746158EBE91004CB9FF /* udis86_syn-intel.c in Sources */,
> 				0FF42747158EBE91004CB9FF /* udis86_syn.c in Sources */,
>+				0F2B9CEA19D0BA7D00B1D1B5 /* DFGPhiChildren.cpp in Sources */,
> 				0FF42732158EBD58004CB9FF /* UDis86Disassembler.cpp in Sources */,
> 				A76F279415F13C9600517D67 /* UnlinkedCodeBlock.cpp in Sources */,
> 				B59F89391891F29F00D5CCDC /* UnlinkedInstructionStream.cpp in Sources */,
>Index: Source/JavaScriptCore/bytecode/StructureSet.h
>===================================================================
>--- Source/JavaScriptCore/bytecode/StructureSet.h	(revision 173938)
>+++ Source/JavaScriptCore/bytecode/StructureSet.h	(working copy)
>@@ -166,6 +166,37 @@ public:
>         return structureList()->list()[structureList()->m_length - 1];
>     }
>     
>+    class iterator {
>+    public:
>+        iterator()
>+            : m_set(nullptr)
>+            , m_index(0)
>+        {
>+        }
>+        
>+        iterator(const StructureSet* set, size_t index)
>+            : m_set(set)
>+            , m_index(index)
>+        {
>+        }
>+        
>+        Structure* operator*() const { return m_set->at(m_index); }
>+        iterator& operator++()
>+        {
>+            m_index++;
>+            return *this;
>+        }
>+        bool operator==(const iterator& other) const { return m_index == other.m_index; }
>+        bool operator!=(const iterator& other) const { return !(*this == other); }
>+        
>+    private:
>+        const StructureSet* m_set;
>+        size_t m_index;
>+    };
>+    
>+    iterator begin() const { return iterator(this, 0); }
>+    iterator end() const { return iterator(this, size()); }
>+    
>     bool operator==(const StructureSet& other) const;
>     
>     SpeculatedType speculationFromStructures() const;
>Index: Source/JavaScriptCore/dfg/DFGAbstractInterpreter.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGAbstractInterpreter.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGAbstractInterpreter.h	(working copy)
>@@ -32,6 +32,7 @@
> #include "DFGBranchDirection.h"
> #include "DFGGraph.h"
> #include "DFGNode.h"
>+#include "DFGPhiChildren.h"
> 
> namespace JSC { namespace DFG {
> 
>@@ -80,18 +81,15 @@ public:
>     //
>     // This is guaranteed to be equivalent to doing:
>     //
>-    // if (state.startExecuting(index)) {
>-    //     state.executeEdges(index);
>-    //     result = state.executeEffects(index);
>-    // } else
>-    //     result = true;
>+    // state.startExecuting()
>+    // state.executeEdges(index);
>+    // result = state.executeEffects(index);
>     bool execute(unsigned indexInBlock);
>     bool execute(Node*);
>     
>-    // Indicate the start of execution of the node. It resets any state in the node
>+    // Indicate the start of execution of a node. It resets any state in the node
>     // that is progressively built up by executeEdges() and executeEffects().
>-    bool startExecuting(Node*);
>-    bool startExecuting(unsigned indexInBlock);
>+    void startExecuting();
>     
>     // Abstractly execute the edges of the given node. This runs filterEdgeByUse()
>     // on all edges of the node. You can skip this step, if you have already used
>@@ -146,6 +144,8 @@ public:
>     FiltrationResult filter(AbstractValue&, SpeculatedType);
>     FiltrationResult filterByValue(AbstractValue&, FrozenValue);
>     
>+    PhiChildren* phiChildren() { return m_phiChildren.get(); }
>+    
> private:
>     void clobberWorld(const CodeOrigin&, unsigned indexInBlock);
>     void clobberCapturedVars(const CodeOrigin&);
>@@ -195,6 +195,7 @@ private:
>     CodeBlock* m_codeBlock;
>     Graph& m_graph;
>     AbstractStateType& m_state;
>+    std::unique_ptr<PhiChildren> m_phiChildren;
> };
> 
> } } // namespace JSC::DFG
>Index: Source/JavaScriptCore/dfg/DFGAbstractInterpreterInlines.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGAbstractInterpreterInlines.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGAbstractInterpreterInlines.h	(working copy)
>@@ -43,6 +43,8 @@ AbstractInterpreter<AbstractStateType>::
>     , m_graph(graph)
>     , m_state(state)
> {
>+    if (m_graph.m_form == SSA)
>+        m_phiChildren = std::make_unique<PhiChildren>(m_graph);
> }
> 
> template<typename AbstractStateType>
>@@ -81,20 +83,12 @@ AbstractInterpreter<AbstractStateType>::
> }
> 
> template<typename AbstractStateType>
>-bool AbstractInterpreter<AbstractStateType>::startExecuting(Node* node)
>+void AbstractInterpreter<AbstractStateType>::startExecuting()
> {
>     ASSERT(m_state.block());
>     ASSERT(m_state.isValid());
>     
>     m_state.setDidClobber(false);
>-    
>-    return node->shouldGenerate();
>-}
>-
>-template<typename AbstractStateType>
>-bool AbstractInterpreter<AbstractStateType>::startExecuting(unsigned indexInBlock)
>-{
>-    return startExecuting(m_state.block()->at(indexInBlock));
> }
> 
> template<typename AbstractStateType>
>@@ -1260,6 +1254,29 @@ bool AbstractInterpreter<AbstractStateTy
>         forNode(node).set(m_graph, node->structure());
>         break;
>         
>+    case PhantomNewObject:
>+    case BottomValue:
>+        m_state.setDidClobber(true); // Prevent constant folding.
>+        // This claims to return bottom.
>+        break;
>+        
>+    case PutByOffsetHint:
>+    case PutStructureHint:
>+        break;
>+        
>+    case MaterializeNewObject: {
>+        StructureSet set;
>+        
>+        m_phiChildren->forAllTransitiveIncomingValues(
>+            m_graph.varArgChild(node, 0).node(),
>+            [&] (Node* incoming) {
>+                set.add(incoming->castConstant<Structure*>());
>+            });
>+        
>+        forNode(node).set(m_graph, set);
>+        break;
>+    }
>+        
>     case CreateActivation:
>         forNode(node).set(
>             m_graph, m_codeBlock->globalObjectFor(node->origin.semantic)->activationStructure());
>@@ -1459,7 +1476,6 @@ bool AbstractInterpreter<AbstractStateTy
>         break;
>         
>     case CheckStructure: {
>-        // FIXME: We should be able to propagate the structure sets of constants (i.e. prototypes).
>         AbstractValue& value = forNode(node->child1());
>         ASSERT(!(value.m_type & ~SpecCell)); // Edge filtering should have already ensured this.
> 
>@@ -1478,6 +1494,50 @@ bool AbstractInterpreter<AbstractStateTy
>         break;
>     }
>         
>+    case CheckStructureImmediate: {
>+        // FIXME: This currently can only reason about one structure at a time.
>+        // https://bugs.webkit.org/show_bug.cgi?id=136988
>+        
>+        AbstractValue& value = forNode(node->child1());
>+        StructureSet& set = node->structureSet();
>+        
>+        if (value.value()) {
>+            if (Structure* structure = jsDynamicCast<Structure*>(value.value())) {
>+                if (set.contains(structure)) {
>+                    m_state.setFoundConstants(true);
>+                    break;
>+                }
>+            }
>+            m_state.setIsValid(false);
>+            break;
>+        }
>+        
>+        if (m_phiChildren) {
>+            bool allGood = true;
>+            m_phiChildren->forAllTransitiveIncomingValues(
>+                node,
>+                [&] (Node* incoming) {
>+                    if (Structure* structure = incoming->dynamicCastConstant<Structure*>()) {
>+                        if (set.contains(structure))
>+                            return;
>+                    }
>+                    allGood = false;
>+                });
>+            if (allGood) {
>+                m_state.setFoundConstants(true);
>+                break;
>+            }
>+        }
>+            
>+        if (Structure* structure = set.onlyStructure()) {
>+            filterByValue(node->child1(), *m_graph.freeze(structure));
>+            break;
>+        }
>+        
>+        // Aw shucks, we can't do anything!
>+        break;
>+    }
>+        
>     case PutStructure:
>         if (!forNode(node->child1()).m_structure.isClear()) {
>             if (forNode(node->child1()).m_structure.onlyStructure() == node->transition()->next)
>@@ -1957,15 +2017,13 @@ bool AbstractInterpreter<AbstractStateTy
> 
>     case CheckTierUpAndOSREnter:
>     case LoopHint:
>-        // We pretend that it can exit because it may want to get all state.
>+    case ZombieHint:
>         break;
> 
>-    case ZombieHint:
>     case Unreachable:
>     case LastNodeType:
>     case ArithIMul:
>     case FiatInt52:
>-    case BottomValue:
>         DFG_CRASH(m_graph, node, "Unexpected node type");
>         break;
>     }
>@@ -1983,9 +2041,8 @@ template<typename AbstractStateType>
> bool AbstractInterpreter<AbstractStateType>::execute(unsigned indexInBlock)
> {
>     Node* node = m_state.block()->at(indexInBlock);
>-    if (!startExecuting(node))
>-        return true;
>     
>+    startExecuting();
>     executeEdges(node);
>     return executeEffects(indexInBlock, node);
> }
>@@ -1993,9 +2050,7 @@ bool AbstractInterpreter<AbstractStateTy
> template<typename AbstractStateType>
> bool AbstractInterpreter<AbstractStateType>::execute(Node* node)
> {
>-    if (!startExecuting(node))
>-        return true;
>-    
>+    startExecuting();
>     executeEdges(node);
>     return executeEffects(UINT_MAX, node);
> }
>Index: Source/JavaScriptCore/dfg/DFGAvailability.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGAvailability.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGAvailability.h	(working copy)
>@@ -85,6 +85,7 @@ public:
>     bool nodeIsUnavailable() const { return m_node == unavailableMarker(); }
>     
>     bool hasNode() const { return !nodeIsUndecided() && !nodeIsUnavailable(); }
>+    bool shouldUseNode() const { return !isFlushUseful() && hasNode(); }
>     
>     Node* node() const
>     {
>@@ -94,6 +95,12 @@ public:
>     }
>     
>     FlushedAt flushedAt() const { return m_flushedAt; }
>+    bool isFlushUseful() const
>+    {
>+        return flushedAt().format() != DeadFlush && flushedAt().format() != ConflictingFlush;
>+    }
>+    
>+    bool isDead() const { return !isFlushUseful() && !hasNode(); }
>     
>     bool operator!() const { return nodeIsUnavailable() && flushedAt().format() == ConflictingFlush; }
> 
>@@ -103,6 +110,11 @@ public:
>             && m_flushedAt == other.m_flushedAt;
>     }
>     
>+    bool operator!=(const Availability& other) const
>+    {
>+        return !(*this == other);
>+    }
>+    
>     Availability merge(const Availability& other) const
>     {
>         return Availability(
>Index: Source/JavaScriptCore/dfg/DFGAvailabilityMap.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGAvailabilityMap.cpp	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGAvailabilityMap.cpp	(working copy)
>@@ -0,0 +1,96 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "DFGAvailabilityMap.h"
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "OperandsInlines.h"
>+#include <wtf/ListDump.h>
>+
>+namespace JSC { namespace DFG {
>+
>+void AvailabilityMap::prune()
>+{
>+    if (m_heap.isEmpty())
>+        return;
>+    
>+    HashSet<Node*> possibleNodes;
>+    
>+    for (unsigned i = m_locals.size(); i--;) {
>+        if (m_locals[i].hasNode())
>+            possibleNodes.add(m_locals[i].node());
>+    }
>+
>+    int oldPossibleNodesSize;
>+    do {
>+        oldPossibleNodesSize = possibleNodes.size();
>+        for (auto pair : m_heap) {
>+            if (pair.value.hasNode() && possibleNodes.contains(pair.key.base()))
>+                possibleNodes.add(pair.value.node());
>+        }
>+    } while (oldPossibleNodesSize != possibleNodes.size());
>+    
>+    HashMap<PromotedHeapLocation, Availability> newHeap;
>+    for (auto pair : m_heap) {
>+        if (possibleNodes.contains(pair.key.base()))
>+            newHeap.add(pair.key, pair.value);
>+    }
>+    m_heap = newHeap;
>+}
>+
>+void AvailabilityMap::clear()
>+{
>+    m_locals.fill(Availability());
>+    m_heap.clear();
>+}
>+
>+void AvailabilityMap::dump(PrintStream& out) const
>+{
>+    out.print("{locals = ", m_locals, "; heap = ", mapDump(m_heap), "}");
>+}
>+
>+bool AvailabilityMap::operator==(const AvailabilityMap& other) const
>+{
>+    return m_locals == other.m_locals
>+        && m_heap == other.m_heap;
>+}
>+
>+void AvailabilityMap::merge(const AvailabilityMap& other)
>+{
>+    for (unsigned i = other.m_locals.size(); i--;)
>+        m_locals[i] = other.m_locals[i].merge(m_locals[i]);
>+    
>+    for (auto pair : other.m_heap) {
>+        auto result = m_heap.add(pair.key, Availability());
>+        result.iterator->value = pair.value.merge(result.iterator->value);
>+    }
>+}
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>Index: Source/JavaScriptCore/dfg/DFGAvailabilityMap.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGAvailabilityMap.h	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGAvailabilityMap.h	(working copy)
>@@ -0,0 +1,64 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef DFGAvailabilityMap_h
>+#define DFGAvailabilityMap_h
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGAvailability.h"
>+#include "DFGPromotedHeapLocation.h"
>+
>+namespace JSC { namespace DFG {
>+
>+struct AvailabilityMap {
>+    void prune();
>+    void clear();
>+    
>+    void dump(PrintStream& out) const;
>+    
>+    bool operator==(const AvailabilityMap& other) const;
>+    
>+    void merge(const AvailabilityMap& other);
>+    
>+    template<typename Functor>
>+    void forEachAvailability(const Functor& functor)
>+    {
>+        for (unsigned i = m_locals.size(); i--;)
>+            functor(m_locals[i]);
>+        for (auto pair : m_heap)
>+            functor(pair.value);
>+    }
>+    
>+    Operands<Availability> m_locals;
>+    HashMap<PromotedHeapLocation, Availability> m_heap;
>+};
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>+#endif // DFGAvailabilityMap_h
>+
>Index: Source/JavaScriptCore/dfg/DFGBasicBlock.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGBasicBlock.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGBasicBlock.cpp	(working copy)
>@@ -118,9 +118,9 @@ void BasicBlock::dump(PrintStream& out) 
> }
> 
> BasicBlock::SSAData::SSAData(BasicBlock* block)
>-    : availabilityAtHead(OperandsLike, block->variablesAtHead)
>-    , availabilityAtTail(OperandsLike, block->variablesAtHead)
> {
>+    availabilityAtHead.m_locals = Operands<Availability>(OperandsLike, block->variablesAtHead);
>+    availabilityAtTail.m_locals = Operands<Availability>(OperandsLike, block->variablesAtHead);
> }
> 
> BasicBlock::SSAData::~SSAData() { }
>Index: Source/JavaScriptCore/dfg/DFGBasicBlock.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGBasicBlock.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGBasicBlock.h	(working copy)
>@@ -30,6 +30,7 @@
> 
> #include "DFGAbstractValue.h"
> #include "DFGAvailability.h"
>+#include "DFGAvailabilityMap.h"
> #include "DFGBranchDirection.h"
> #include "DFGFlushedAt.h"
> #include "DFGNode.h"
>@@ -46,6 +47,7 @@ class Graph;
> class InsertionSet;
> 
> typedef Vector<BasicBlock*, 2> PredecessorList;
>+typedef Vector<Node*, 8> BlockNodeList;
> 
> struct BasicBlock : RefCounted<BasicBlock> {
>     BasicBlock(
>@@ -85,6 +87,9 @@ struct BasicBlock : RefCounted<BasicBloc
>     bool isInPhis(Node* node) const;
>     bool isInBlock(Node* myNode) const;
>     
>+    BlockNodeList::iterator begin() { return m_nodes.begin(); }
>+    BlockNodeList::iterator end() { return m_nodes.end(); }
>+    
>     unsigned numSuccessors() { return last()->numSuccessors(); }
>     
>     BasicBlock*& successor(unsigned index)
>@@ -96,6 +101,76 @@ struct BasicBlock : RefCounted<BasicBloc
>         return last()->successorForCondition(condition);
>     }
>     
>+    class SuccessorsIterable {
>+    public:
>+        SuccessorsIterable()
>+            : m_block(nullptr)
>+        {
>+        }
>+        
>+        SuccessorsIterable(BasicBlock* block)
>+            : m_block(block)
>+        {
>+        }
>+        
>+        class iterator {
>+        public:
>+            iterator()
>+                : m_block(nullptr)
>+                , m_index(UINT_MAX)
>+            {
>+            }
>+            
>+            iterator(BasicBlock* block, unsigned index)
>+                : m_block(block)
>+                , m_index(index)
>+            {
>+            }
>+            
>+            BasicBlock* operator*()
>+            {
>+                return m_block->successor(m_index);
>+            }
>+            
>+            iterator& operator++()
>+            {
>+                m_index++;
>+                return *this;
>+            }
>+            
>+            bool operator==(const iterator& other) const
>+            {
>+                return m_index == other.m_index;
>+            }
>+            
>+            bool operator!=(const iterator& other) const
>+            {
>+                return !(*this == other);
>+            }
>+        private:
>+            BasicBlock* m_block;
>+            unsigned m_index;
>+        };
>+        
>+        iterator begin()
>+        {
>+            return iterator(m_block, 0);
>+        }
>+        
>+        iterator end()
>+        {
>+            return iterator(m_block, m_block->numSuccessors());
>+        }
>+        
>+    private:
>+        BasicBlock* m_block;
>+    };
>+    
>+    SuccessorsIterable successors()
>+    {
>+        return SuccessorsIterable(this);
>+    }
>+    
>     void removePredecessor(BasicBlock* block);
>     void replacePredecessor(BasicBlock* from, BasicBlock* to);
> 
>@@ -169,8 +244,9 @@ struct BasicBlock : RefCounted<BasicBloc
>     unsigned innerMostLoopIndices[numberOfInnerMostLoopIndices];
> 
>     struct SSAData {
>-        Operands<Availability> availabilityAtHead;
>-        Operands<Availability> availabilityAtTail;
>+        AvailabilityMap availabilityAtHead;
>+        AvailabilityMap availabilityAtTail;
>+        
>         HashSet<Node*> liveAtHead;
>         HashSet<Node*> liveAtTail;
>         HashMap<Node*, AbstractValue> valuesAtHead;
>@@ -183,7 +259,7 @@ struct BasicBlock : RefCounted<BasicBloc
>     
> private:
>     friend class InsertionSet;
>-    Vector<Node*, 8> m_nodes;
>+    BlockNodeList m_nodes;
> };
> 
> typedef Vector<BasicBlock*, 5> BlockList;
>Index: Source/JavaScriptCore/dfg/DFGClobberize.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGClobberize.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGClobberize.h	(working copy)
>@@ -109,6 +109,7 @@ void clobberize(Graph& graph, Node* node
>     case HardPhantom:
>     case Check:
>     case ExtractOSREntryLocal:
>+    case CheckStructureImmediate:
>         return;
>         
>     case BitAnd:
>@@ -273,6 +274,8 @@ void clobberize(Graph& graph, Node* node
>     case ProfileDidCall:
>     case StoreBarrier:
>     case StoreBarrierWithNullCheck:
>+    case PutByOffsetHint:
>+    case PutStructureHint:
>         write(SideState);
>         return;
>         
>@@ -787,17 +790,15 @@ void clobberize(Graph& graph, Node* node
>     case NewObject:
>     case NewRegexp:
>     case NewStringObject:
>-        read(HeapObjectCount);
>-        write(HeapObjectCount);
>-        return;
>-        
>+    case PhantomNewObject:
>+    case MaterializeNewObject:
>     case NewFunctionNoCheck:
>     case NewFunction:
>     case NewFunctionExpression:
>         read(HeapObjectCount);
>         write(HeapObjectCount);
>         return;
>-
>+        
>     case RegExpExec:
>     case RegExpTest:
>         read(RegExpState);
>Index: Source/JavaScriptCore/dfg/DFGConstantFoldingPhase.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGConstantFoldingPhase.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGConstantFoldingPhase.cpp	(working copy)
>@@ -124,6 +124,42 @@ private:
>                 break;
>             }
>                 
>+            case CheckStructureImmediate: {
>+                AbstractValue& value = m_state.forNode(node->child1());
>+                StructureSet& set = node->structureSet();
>+                
>+                if (value.value()) {
>+                    if (Structure* structure = jsDynamicCast<Structure*>(value.value())) {
>+                        if (set.contains(structure)) {
>+                            m_interpreter.execute(indexInBlock);
>+                            node->convertToPhantom();
>+                            eliminated = true;
>+                            break;
>+                        }
>+                    }
>+                }
>+                
>+                if (PhiChildren* phiChildren = m_interpreter.phiChildren()) {
>+                    bool allGood = true;
>+                    phiChildren->forAllTransitiveIncomingValues(
>+                        node,
>+                        [&] (Node* incoming) {
>+                            if (Structure* structure = incoming->dynamicCastConstant<Structure*>()) {
>+                                if (set.contains(structure))
>+                                    return;
>+                            }
>+                            allGood = false;
>+                        });
>+                    if (allGood) {
>+                        m_interpreter.execute(indexInBlock);
>+                        node->convertToPhantom();
>+                        eliminated = true;
>+                        break;
>+                    }
>+                }
>+                break;
>+            }
>+                
>             case CheckArray:
>             case Arrayify: {
>                 if (!node->arrayMode().alreadyChecked(m_graph, node, m_state.forNode(node->child1())))
>Index: Source/JavaScriptCore/dfg/DFGDoesGC.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGDoesGC.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGDoesGC.cpp	(working copy)
>@@ -199,6 +199,10 @@ bool doesGC(Graph& graph, Node* node)
>     case BooleanToNumber:
>     case CheckBadCell:
>     case BottomValue:
>+    case PhantomNewObject:
>+    case PutByOffsetHint:
>+    case CheckStructureImmediate:
>+    case PutStructureHint:
>         return false;
> 
>     case CreateActivation:
>@@ -225,6 +229,7 @@ bool doesGC(Graph& graph, Node* node)
>     case GetGenericPropertyEnumerator:
>     case GetEnumeratorPname:
>     case ToIndexString:
>+    case MaterializeNewObject:
>         return true;
>         
>     case MultiPutByOffset:
>Index: Source/JavaScriptCore/dfg/DFGFixupPhase.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGFixupPhase.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGFixupPhase.cpp	(working copy)
>@@ -1013,6 +1013,11 @@ private:
>         case Int52Constant:
>         case Identity: // This should have been cleaned up.
>         case BooleanToNumber:
>+        case PhantomNewObject:
>+        case PutByOffsetHint:
>+        case CheckStructureImmediate:
>+        case PutStructureHint:
>+        case MaterializeNewObject:
>             // These are just nodes that we don't currently expect to see during fixup.
>             // If we ever wanted to insert them prior to fixup, then we just have to create
>             // fixup rules for them.
>Index: Source/JavaScriptCore/dfg/DFGFlushedAt.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGFlushedAt.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGFlushedAt.cpp	(working copy)
>@@ -36,8 +36,10 @@ void FlushedAt::dump(PrintStream& out) c
> {
>     if (m_format == DeadFlush || m_format == ConflictingFlush)
>         out.print(m_format);
>-    else
>+    else if (m_virtualRegister.isValid())
>         out.print("r", m_virtualRegister, ":", m_format);
>+    else
>+        out.print(m_format);
> }
> 
> void FlushedAt::dumpInContext(PrintStream& out, DumpContext*) const
>Index: Source/JavaScriptCore/dfg/DFGFlushedAt.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGFlushedAt.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGFlushedAt.h	(working copy)
>@@ -52,8 +52,6 @@ public:
>     {
>         if (format == DeadFlush)
>             ASSERT(!virtualRegister.isValid());
>-        else
>-            ASSERT(virtualRegister.isValid());
>     }
>     
>     bool operator!() const { return m_format == DeadFlush; }
>Index: Source/JavaScriptCore/dfg/DFGGraph.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGGraph.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGGraph.cpp	(working copy)
>@@ -323,6 +323,8 @@ void Graph::dump(PrintStream& out, const
>         out.print(comma, inContext(JSValue(node->typedArray()), context));
>     if (node->hasStoragePointer())
>         out.print(comma, RawPointer(node->storagePointer()));
>+    if (node->hasObjectMaterializationData())
>+        out.print(comma, node->objectMaterializationData());
>     if (node->isConstant())
>         out.print(comma, pointerDumpInContext(node->constant(), context));
>     if (node->isJump())
>@@ -368,12 +370,21 @@ void Graph::dumpBlockHeader(PrintStream&
>     for (size_t i = 0; i < block->predecessors.size(); ++i)
>         out.print(" ", *block->predecessors[i]);
>     out.print("\n");
>+    out.print(prefix, "  Successors:");
>+    for (BasicBlock* successor : block->successors()) {
>+        out.print(" ", *successor);
>+        if (m_prePostNumbering.isValid())
>+            out.print(" (", m_prePostNumbering.edgeKind(block, successor), ")");
>+    }
>+    out.print("\n");
>     if (m_dominators.isValid()) {
>         out.print(prefix, "  Dominated by: ", m_dominators.dominatorsOf(block), "\n");
>         out.print(prefix, "  Dominates: ", m_dominators.blocksDominatedBy(block), "\n");
>         out.print(prefix, "  Dominance Frontier: ", m_dominators.dominanceFrontierOf(block), "\n");
>         out.print(prefix, "  Iterated Dominance Frontier: ", m_dominators.iteratedDominanceFrontierOf(BlockList(1, block)), "\n");
>     }
>+    if (m_prePostNumbering.isValid())
>+        out.print(prefix, "  Pre/Post Numbering: ", m_prePostNumbering.preNumber(block), "/", m_prePostNumbering.postNumber(block), "\n");
>     if (m_naturalLoops.isValid()) {
>         if (const NaturalLoop* loop = m_naturalLoops.headerOf(block)) {
>             out.print(prefix, "  Loop header, contains:");
>@@ -562,6 +573,27 @@ void Graph::resetReachability()
>     determineReachability();
> }
> 
>+void Graph::mergeRelevantToOSR()
>+{
>+    for (BasicBlock* block : blocksInNaturalOrder()) {
>+        for (Node* node : *block) {
>+            switch (node->op()) {
>+            case MovHint:
>+                node->child1()->mergeFlags(NodeRelevantToOSR);
>+                break;
>+                
>+            case PutStructureHint:
>+            case PutByOffsetHint:
>+                node->child2()->mergeFlags(NodeRelevantToOSR);
>+                break;
>+                
>+            default:
>+                break;
>+            }
>+        }
>+    }
>+}
>+
> namespace {
> 
> class RefCountCalculator {
>@@ -707,6 +739,7 @@ void Graph::invalidateCFG()
> {
>     m_dominators.invalidate();
>     m_naturalLoops.invalidate();
>+    m_prePostNumbering.invalidate();
> }
> 
> void Graph::substituteGetLocal(BasicBlock& block, unsigned startIndexInBlock, VariableAccessData* variableAccessData, Node* newGetLocal)
>Index: Source/JavaScriptCore/dfg/DFGGraph.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGGraph.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGGraph.h	(working copy)
>@@ -39,6 +39,7 @@
> #include "DFGNode.h"
> #include "DFGNodeAllocator.h"
> #include "DFGPlan.h"
>+#include "DFGPrePostNumbering.h"
> #include "DFGScannable.h"
> #include "JSStack.h"
> #include "MethodOfGettingAValueProfile.h"
>@@ -55,6 +56,47 @@ class ExecState;
> 
> namespace DFG {
> 
>+#define DFG_NODE_DO_TO_CHILDREN(graph, node, thingToDo) do {            \
>+        Node* _node = (node);                                           \
>+        if (_node->flags() & NodeHasVarArgs) {                          \
>+            for (unsigned _childIdx = _node->firstChild();              \
>+                _childIdx < _node->firstChild() + _node->numChildren(); \
>+                _childIdx++) {                                          \
>+                if (!!(graph).m_varArgChildren[_childIdx])              \
>+                    thingToDo(_node, (graph).m_varArgChildren[_childIdx]); \
>+            }                                                           \
>+        } else {                                                        \
>+            if (!_node->child1()) {                                     \
>+                ASSERT(                                                 \
>+                    !_node->child2()                                    \
>+                    && !_node->child3());                               \
>+                break;                                                  \
>+            }                                                           \
>+            thingToDo(_node, _node->child1());                          \
>+                                                                        \
>+            if (!_node->child2()) {                                     \
>+                ASSERT(!_node->child3());                               \
>+                break;                                                  \
>+            }                                                           \
>+            thingToDo(_node, _node->child2());                          \
>+                                                                        \
>+            if (!_node->child3())                                       \
>+                break;                                                  \
>+            thingToDo(_node, _node->child3());                          \
>+        }                                                               \
>+    } while (false)
>+
>+#define DFG_ASSERT(graph, node, assertion) do {                         \
>+        if (!!(assertion))                                              \
>+            break;                                                      \
>+        (graph).handleAssertionFailure(                                 \
>+            (node), __FILE__, __LINE__, WTF_PRETTY_FUNCTION, #assertion); \
>+    } while (false)
>+
>+#define DFG_CRASH(graph, node, reason)                                  \
>+    (graph).handleAssertionFailure(                                     \
>+        (node), __FILE__, __LINE__, WTF_PRETTY_FUNCTION, (reason));
>+
> struct InlineVariableData {
>     InlineCallFrame* inlineCallFrame;
>     unsigned argumentPositionStart;
>@@ -565,6 +607,8 @@ public:
>     void determineReachability();
>     void resetReachability();
>     
>+    void mergeRelevantToOSR();
>+    
>     void computeRefCounts();
>     
>     unsigned varArgNumChildren(Node* node)
>@@ -676,6 +720,100 @@ public:
>     BlockList blocksInPreOrder();
>     BlockList blocksInPostOrder();
>     
>+    class NaturalBlockIterable {
>+    public:
>+        NaturalBlockIterable()
>+            : m_graph(nullptr)
>+        {
>+        }
>+        
>+        NaturalBlockIterable(Graph& graph)
>+            : m_graph(&graph)
>+        {
>+        }
>+        
>+        class iterator {
>+        public:
>+            iterator()
>+                : m_graph(nullptr)
>+                , m_index(0)
>+            {
>+            }
>+            
>+            iterator(Graph& graph, BlockIndex index)
>+                : m_graph(&graph)
>+                , m_index(findNext(index))
>+            {
>+            }
>+            
>+            BasicBlock *operator*()
>+            {
>+                return m_graph->block(m_index);
>+            }
>+            
>+            iterator& operator++()
>+            {
>+                m_index = findNext(m_index + 1);
>+                return *this;
>+            }
>+            
>+            bool operator==(const iterator& other) const
>+            {
>+                return m_index == other.m_index;
>+            }
>+            
>+            bool operator!=(const iterator& other) const
>+            {
>+                return !(*this == other);
>+            }
>+            
>+        private:
>+            BlockIndex findNext(BlockIndex index)
>+            {
>+                while (index < m_graph->numBlocks() && !m_graph->block(index))
>+                    index++;
>+                return index;
>+            }
>+            
>+            Graph* m_graph;
>+            BlockIndex m_index;
>+        };
>+        
>+        iterator begin()
>+        {
>+            return iterator(*m_graph, 0);
>+        }
>+        
>+        iterator end()
>+        {
>+            return iterator(*m_graph, m_graph->numBlocks());
>+        }
>+        
>+    private:
>+        Graph* m_graph;
>+    };
>+    
>+    NaturalBlockIterable blocksInNaturalOrder()
>+    {
>+        return NaturalBlockIterable(*this);
>+    }
>+    
>+    template<typename ChildFunctor>
>+    void doToChildrenWithNode(Node* node, const ChildFunctor& functor)
>+    {
>+        DFG_NODE_DO_TO_CHILDREN(*this, node, functor);
>+    }
>+    
>+    template<typename ChildFunctor>
>+    void doToChildren(Node* node, const ChildFunctor& functor)
>+    {
>+        doToChildrenWithNode(
>+            node,
>+            [&functor] (Node*, Edge& edge) {
>+                functor(edge);
>+            });
>+    }
>+    
>     Profiler::Compilation* compilation() { return m_plan.compilation.get(); }
>     
>     DesiredIdentifiers& identifiers() { return m_plan.identifiers; }
>@@ -736,12 +874,14 @@ public:
>     Bag<SwitchData> m_switchData;
>     Bag<MultiGetByOffsetData> m_multiGetByOffsetData;
>     Bag<MultiPutByOffsetData> m_multiPutByOffsetData;
>+    Bag<ObjectMaterializationData> m_objectMaterializationData;
>     Vector<InlineVariableData, 4> m_inlineVariableData;
>     HashMap<CodeBlock*, std::unique_ptr<FullBytecodeLiveness>> m_bytecodeLiveness;
>     bool m_hasArguments;
>     HashSet<ExecutableBase*> m_executablesWhoseArgumentsEscaped;
>     BitVector m_lazyVars;
>     Dominators m_dominators;
>+    PrePostNumbering m_prePostNumbering;
>     NaturalLoops m_naturalLoops;
>     unsigned m_localVars;
>     unsigned m_nextMachineLocal;
>@@ -786,47 +926,6 @@ private:
>     }
> };
> 
>-#define DFG_NODE_DO_TO_CHILDREN(graph, node, thingToDo) do {            \
>-        Node* _node = (node);                                           \
>-        if (_node->flags() & NodeHasVarArgs) {                          \
>-            for (unsigned _childIdx = _node->firstChild();              \
>-                _childIdx < _node->firstChild() + _node->numChildren(); \
>-                _childIdx++) {                                          \
>-                if (!!(graph).m_varArgChildren[_childIdx])              \
>-                    thingToDo(_node, (graph).m_varArgChildren[_childIdx]); \
>-            }                                                           \
>-        } else {                                                        \
>-            if (!_node->child1()) {                                     \
>-                ASSERT(                                                 \
>-                    !_node->child2()                                    \
>-                    && !_node->child3());                               \
>-                break;                                                  \
>-            }                                                           \
>-            thingToDo(_node, _node->child1());                          \
>-                                                                        \
>-            if (!_node->child2()) {                                     \
>-                ASSERT(!_node->child3());                               \
>-                break;                                                  \
>-            }                                                           \
>-            thingToDo(_node, _node->child2());                          \
>-                                                                        \
>-            if (!_node->child3())                                       \
>-                break;                                                  \
>-            thingToDo(_node, _node->child3());                          \
>-        }                                                               \
>-    } while (false)
>-
>-#define DFG_ASSERT(graph, node, assertion) do {                         \
>-        if (!!(assertion))                                              \
>-            break;                                                      \
>-        (graph).handleAssertionFailure(                                 \
>-            (node), __FILE__, __LINE__, WTF_PRETTY_FUNCTION, #assertion); \
>-    } while (false)
>-
>-#define DFG_CRASH(graph, node, reason)                                  \
>-    (graph).handleAssertionFailure(                                     \
>-        (node), __FILE__, __LINE__, WTF_PRETTY_FUNCTION, (reason));
>-
> } } // namespace JSC::DFG
> 
> #endif
>Index: Source/JavaScriptCore/dfg/DFGHeapLocation.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGHeapLocation.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGHeapLocation.cpp	(working copy)
>@@ -147,6 +147,10 @@ void printInternal(PrintStream& out, Loc
>     case AllocationProfileWatchpointLoc:
>         out.print("AllocationProfileWatchpointLoc");
>         return;
>+        
>+    case StructureLoc:
>+        out.print("StructureLoc");
>+        return;
>     }
>     
>     RELEASE_ASSERT_NOT_REACHED();
>Index: Source/JavaScriptCore/dfg/DFGHeapLocation.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGHeapLocation.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGHeapLocation.h	(working copy)
>@@ -55,6 +55,7 @@ enum LocationKind {
>     MyArgumentsLengthLoc,
>     NamedPropertyLoc,
>     SetterLoc,
>+    StructureLoc,
>     TypeOfLoc,
>     TypedArrayByteOffsetLoc,
>     VarInjectionWatchpointLoc,
>Index: Source/JavaScriptCore/dfg/DFGInsertOSRHintsForUpdate.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGInsertOSRHintsForUpdate.cpp	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGInsertOSRHintsForUpdate.cpp	(working copy)
>@@ -0,0 +1,60 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "DFGInsertOSRHintsForUpdate.h"
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "JSCInlines.h"
>+
>+namespace JSC { namespace DFG {
>+
>+void insertOSRHintsForUpdate(
>+    InsertionSet& insertionSet, unsigned nodeIndex, NodeOrigin origin,
>+    AvailabilityMap& availability, Node* originalNode, Node* newNode)
>+{
>+    for (unsigned i = availability.m_locals.size(); i--;) {
>+        int operand = availability.m_locals.operandForIndex(i);
>+        
>+        if (availability.m_locals[i].hasNode() && availability.m_locals[i].node() == originalNode) {
>+            insertionSet.insertNode(
>+                nodeIndex, SpecNone, MovHint, origin, OpInfo(operand),
>+                newNode->defaultEdge());
>+        }
>+    }
>+    
>+    for (auto pair : availability.m_heap) {
>+        if (pair.value.hasNode() && pair.value.node() == originalNode) {
>+            insertionSet.insert(
>+                nodeIndex, pair.key.createHint(insertionSet.graph(), origin, newNode));
>+        }
>+    }
>+}
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>Index: Source/JavaScriptCore/dfg/DFGInsertOSRHintsForUpdate.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGInsertOSRHintsForUpdate.h	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGInsertOSRHintsForUpdate.h	(working copy)
>@@ -0,0 +1,45 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef DFGInsertOSRHintsForUpdate_h
>+#define DFGInsertOSRHintsForUpdate_h
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGAvailabilityMap.h"
>+#include "DFGInsertionSet.h"
>+
>+namespace JSC { namespace DFG {
>+
>+void insertOSRHintsForUpdate(
>+    InsertionSet&, unsigned nodeIndex, NodeOrigin, AvailabilityMap&,
>+    Node* originalNode, Node* newNode);
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>+#endif // DFGInsertOSRHintsForUpdate_h
>+
>Index: Source/JavaScriptCore/dfg/DFGInsertionSet.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGInsertionSet.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGInsertionSet.h	(working copy)
>@@ -43,6 +43,8 @@ public:
>     {
>     }
>     
>+    Graph& graph() { return m_graph; }
>+    
>     Node* insert(const Insertion& insertion)
>     {
>         ASSERT(!m_insertions.size() || m_insertions.last().index() <= insertion.index());
>Index: Source/JavaScriptCore/dfg/DFGMayExit.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGMayExit.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGMayExit.cpp	(working copy)
>@@ -75,6 +75,10 @@ bool mayExit(Graph& graph, Node* node)
>     case Phi:
>     case Upsilon:
>     case ZombieHint:
>+    case BottomValue:
>+    case PutStructureHint:
>+    case PutByOffsetHint:
>+    case PhantomNewObject:
>         break;
>         
>     default:
>Index: Source/JavaScriptCore/dfg/DFGNode.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGNode.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGNode.h	(working copy)
>@@ -38,6 +38,7 @@
> #include "DFGNodeFlags.h"
> #include "DFGNodeOrigin.h"
> #include "DFGNodeType.h"
>+#include "DFGObjectMaterializationData.h"
> #include "DFGTransition.h"
> #include "DFGUseKind.h"
> #include "DFGVariableAccessData.h"
>@@ -500,6 +501,35 @@ struct Node {
>         m_flags &= ~NodeClobbersWorld;
>     }
>     
>+    void convertToPutByOffsetHint()
>+    {
>+        ASSERT(m_op == PutByOffset);
>+        m_opInfo = storageAccessData().identifierNumber;
>+        m_op = PutByOffsetHint;
>+        child1() = child2();
>+        child2() = child3();
>+        child3() = Edge();
>+    }
>+    
>+    void convertToPutStructureHint(Node* structure)
>+    {
>+        ASSERT(m_op == PutStructure);
>+        ASSERT(structure->castConstant<Structure*>() == transition()->next);
>+        m_op = PutStructureHint;
>+        m_opInfo = 0;
>+        child2() = Edge(structure, KnownCellUse);
>+    }
>+    
>+    void convertToPhantomNewObject()
>+    {
>+        ASSERT(m_op == NewObject || m_op == MaterializeNewObject);
>+        m_op = PhantomNewObject;
>+        m_flags &= ~NodeHasVarArgs;
>+        m_opInfo = 0;
>+        m_opInfo2 = 0;
>+        children = AdjacencyList();
>+    }
>+    
>     void convertToPhantomLocal()
>     {
>         ASSERT(m_op == Phantom && (child1()->op() == Phi || child1()->op() == SetLocal || child1()->op() == SetArgument));
>@@ -580,7 +610,7 @@ struct Node {
>      
>     bool isCellConstant()
>     {
>-        return isConstant() && constant()->value().isCell();
>+        return isConstant() && constant()->value() && constant()->value().isCell();
>     }
>      
>     JSCell* asCell()
>@@ -595,6 +625,14 @@ struct Node {
>             return nullptr;
>         return jsDynamicCast<T>(asCell());
>     }
>+    
>+    template<typename T>
>+    T castConstant()
>+    {
>+        T result = dynamicCastConstant<T>();
>+        RELEASE_ASSERT(result);
>+        return result;
>+    }
>      
>     bool containsMovHint()
>     {
>@@ -704,6 +742,7 @@ struct Node {
>         case PutById:
>         case PutByIdFlush:
>         case PutByIdDirect:
>+        case PutByOffsetHint:
>             return true;
>         default:
>             return false;
>@@ -1155,7 +1194,14 @@ struct Node {
>     
>     bool hasStorageAccessData()
>     {
>-        return op() == GetByOffset || op() == GetGetterSetterByOffset || op() == PutByOffset;
>+        switch (op()) {
>+        case GetByOffset:
>+        case PutByOffset:
>+        case GetGetterSetterByOffset:
>+            return true;
>+        default:
>+            return false;
>+        }
>     }
>     
>     StorageAccessData& storageAccessData()
>@@ -1184,6 +1230,26 @@ struct Node {
>         return *reinterpret_cast<MultiPutByOffsetData*>(m_opInfo);
>     }
>     
>+    bool hasObjectMaterializationData()
>+    {
>+        return op() == MaterializeNewObject;
>+    }
>+    
>+    ObjectMaterializationData& objectMaterializationData()
>+    {
>+        return *reinterpret_cast<ObjectMaterializationData*>(m_opInfo);
>+    }
>+    
>+    bool isPhantomObjectAllocation()
>+    {
>+        switch (op()) {
>+        case PhantomNewObject:
>+            return true;
>+        default:
>+            return false;
>+        }
>+    }
>+    
>     bool hasFunctionDeclIndex()
>     {
>         return op() == NewFunction
>Index: Source/JavaScriptCore/dfg/DFGNodeType.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGNodeType.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGNodeType.h	(working copy)
>@@ -228,6 +228,13 @@ namespace JSC { namespace DFG {
>     macro(NewTypedArray, NodeResultJS | NodeClobbersWorld | NodeMustGenerate) \
>     macro(NewRegexp, NodeResultJS) \
>     \
>+    /* Support for allocation sinking. */\
>+    macro(PhantomNewObject, NodeResultJS) \
>+    macro(PutByOffsetHint, NodeMustGenerate) \
>+    macro(CheckStructureImmediate, NodeMustGenerate) \
>+    macro(PutStructureHint, NodeMustGenerate) \
>+    macro(MaterializeNewObject, NodeResultJS | NodeHasVarArgs) \
>+    \
>     /* Nodes for misc operations. */\
>     macro(Breakpoint, NodeMustGenerate) \
>     macro(ProfileWillCall, NodeMustGenerate) \
>Index: Source/JavaScriptCore/dfg/DFGOSRAvailabilityAnalysisPhase.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGOSRAvailabilityAnalysisPhase.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGOSRAvailabilityAnalysisPhase.cpp	(working copy)
>@@ -32,6 +32,7 @@
> #include "DFGGraph.h"
> #include "DFGInsertionSet.h"
> #include "DFGPhase.h"
>+#include "DFGPromoteHeapAccess.h"
> #include "JSCInlines.h"
> 
> namespace JSC { namespace DFG {
>@@ -51,25 +52,18 @@ public:
>             BasicBlock* block = m_graph.block(blockIndex);
>             if (!block)
>                 continue;
>-            block->ssa->availabilityAtHead.fill(Availability());
>-            block->ssa->availabilityAtTail.fill(Availability());
>+            block->ssa->availabilityAtHead.clear();
>+            block->ssa->availabilityAtTail.clear();
>         }
>         
>         BasicBlock* root = m_graph.block(0);
>-        for (unsigned argument = root->ssa->availabilityAtHead.numberOfArguments(); argument--;) {
>-            root->ssa->availabilityAtHead.argument(argument) =
>+        root->ssa->availabilityAtHead.m_locals.fill(Availability::unavailable());
>+        for (unsigned argument = root->ssa->availabilityAtHead.m_locals.numberOfArguments(); argument--;) {
>+            root->ssa->availabilityAtHead.m_locals.argument(argument) =
>                 Availability::unavailable().withFlush(
>                     FlushedAt(FlushedJSValue, virtualRegisterForArgument(argument)));
>         }
> 
>-        if (m_graph.m_plan.mode == FTLForOSREntryMode) {
>-            for (unsigned local = m_graph.m_profiledBlock->m_numCalleeRegisters; local--;)
>-                root->ssa->availabilityAtHead.local(local) = Availability::unavailable();
>-        } else {
>-            for (unsigned local = root->ssa->availabilityAtHead.numberOfLocals(); local--;)
>-                root->ssa->availabilityAtHead.local(local) = Availability::unavailable();
>-        }
>-        
>         // This could be made more efficient by processing blocks in reverse postorder.
>         
>         LocalOSRAvailabilityCalculator calculator;
>@@ -87,6 +81,8 @@ public:
>                 for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex)
>                     calculator.executeNode(block->at(nodeIndex));
>                 
>+                calculator.m_availability.prune();
>+                
>                 if (calculator.m_availability == block->ssa->availabilityAtTail)
>                     continue;
>                 
>@@ -95,11 +91,7 @@ public:
>                 
>                 for (unsigned successorIndex = block->numSuccessors(); successorIndex--;) {
>                     BasicBlock* successor = block->successor(successorIndex);
>-                    for (unsigned i = calculator.m_availability.size(); i--;) {
>-                        successor->ssa->availabilityAtHead[i] =
>-                            calculator.m_availability[i].merge(
>-                                successor->ssa->availabilityAtHead[i]);
>-                    }
>+                    successor->ssa->availabilityAtHead.merge(calculator.m_availability);
>                 }
>             }
>         } while (changed);
>@@ -127,38 +119,50 @@ void LocalOSRAvailabilityCalculator::beg
>     m_availability = block->ssa->availabilityAtHead;
> }
> 
>+void LocalOSRAvailabilityCalculator::endBlock(BasicBlock* block)
>+{
>+    m_availability = block->ssa->availabilityAtTail;
>+}
>+
> void LocalOSRAvailabilityCalculator::executeNode(Node* node)
> {
>     switch (node->op()) {
>     case SetLocal: {
>         VariableAccessData* variable = node->variableAccessData();
>-        m_availability.operand(variable->local()) =
>+        m_availability.m_locals.operand(variable->local()) =
>             Availability(node->child1().node(), variable->flushedAt());
>         break;
>     }
> 
>     case GetArgument: {
>         VariableAccessData* variable = node->variableAccessData();
>-        m_availability.operand(variable->local()) =
>+        m_availability.m_locals.operand(variable->local()) =
>             Availability(node, variable->flushedAt());
>         break;
>     }
> 
>     case MovHint: {
>-        m_availability.operand(node->unlinkedLocal()) =
>+        m_availability.m_locals.operand(node->unlinkedLocal()) =
>             Availability(node->child1().node());
>         break;
>     }
> 
>     case ZombieHint: {
>-        m_availability.operand(node->unlinkedLocal()) =
>+        m_availability.m_locals.operand(node->unlinkedLocal()) =
>             Availability::unavailable();
>         break;
>     }
>-
>+        
>     default:
>         break;
>     }
>+    
>+    promoteHeapAccess(
>+        node,
>+        [&] (PromotedHeapLocation location, Edge value) {
>+            m_availability.m_heap.set(location, Availability(value.node()));
>+        },
>+        [&] (PromotedHeapLocation) { });
> }
> 
> } } // namespace JSC::DFG
>Index: Source/JavaScriptCore/dfg/DFGOSRAvailabilityAnalysisPhase.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGOSRAvailabilityAnalysisPhase.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGOSRAvailabilityAnalysisPhase.h	(working copy)
>@@ -37,7 +37,9 @@ class Graph;
> 
> // Computes BasicBlock::ssa->availabiltiyAtHead/Tail. This is a forward flow type inference
> // over MovHints and SetLocals. This analysis is run directly by the Plan for preparing for
>-// lowering to LLVM IR, but it can also be used as a utility.
>+// lowering to LLVM IR, but it can also be used as a utility. Note that if you run it before
>+// stack layout, all of the flush availability will omit the virtual register - but it will
>+// tell you the format.
> 
> bool performOSRAvailabilityAnalysis(Graph&);
> 
>@@ -49,9 +51,10 @@ public:
>     ~LocalOSRAvailabilityCalculator();
>     
>     void beginBlock(BasicBlock*);
>+    void endBlock(BasicBlock*); // Useful if you want to get data for the end of the block. You don't need to call this if you did beginBlock() and then executeNode() for every node.
>     void executeNode(Node*);
>     
>-    Operands<Availability> m_availability;
>+    AvailabilityMap m_availability;
> };
> 
> } } // namespace JSC::DFG
>Index: Source/JavaScriptCore/dfg/DFGObjectAllocationSinkingPhase.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGObjectAllocationSinkingPhase.cpp	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGObjectAllocationSinkingPhase.cpp	(working copy)
>@@ -0,0 +1,807 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "DFGObjectAllocationSinkingPhase.h"
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGAbstractHeap.h"
>+#include "DFGBlockMapInlines.h"
>+#include "DFGClobberize.h"
>+#include "DFGGraph.h"
>+#include "DFGInsertOSRHintsForUpdate.h"
>+#include "DFGInsertionSet.h"
>+#include "DFGLivenessAnalysisPhase.h"
>+#include "DFGOSRAvailabilityAnalysisPhase.h"
>+#include "DFGPhase.h"
>+#include "DFGPromoteHeapAccess.h"
>+#include "DFGSSACalculator.h"
>+#include "DFGValidate.h"
>+#include "JSCInlines.h"
>+
>+namespace JSC { namespace DFG {
>+
>+static bool verbose = false;
>+
>+class ObjectAllocationSinkingPhase : public Phase {
>+public:
>+    ObjectAllocationSinkingPhase(Graph& graph)
>+        : Phase(graph, "object allocation sinking")
>+        , m_ssaCalculator(graph)
>+        , m_insertionSet(graph)
>+    {
>+    }
>+    
>+    bool run()
>+    {
>+        ASSERT(m_graph.m_fixpointState == FixpointNotConverged);
>+        
>+        m_graph.m_dominators.computeIfNecessary(m_graph);
>+        
>+        // Logically we wish to consider every NewObject and sink it. However it's probably not
>+        // profitable to sink a NewObject that will always escape. So, first we do a very simple
>+        // forward flow analysis that determines the set of NewObject nodes that have any chance
>+        // of benefiting from object allocation sinking. Then we fixpoint the following rules:
>+        //
>+        // - For each NewObject, we turn the original NewObject into a PhantomNewObject and then
>+        //   we insert MaterializeNewObject just before those escaping sites that come before any
>+        //   other escaping sites - that is, there is no path between the allocation and those sites
>+        //   that would see any other escape. Note that Upsilons constitute escaping sites. Then we
>+        //   insert additional MaterializeNewObject nodes on Upsilons that feed into Phis that mix
>+        //   materializations and the original PhantomNewObject. We then turn each PutByOffset over a
>+        //   PhantomNewObject into a PutByOffsetHint.
>+        //
>+        // - We perform the same optimization for MaterializeNewObject. This allows us to cover
>+        //   cases where we had MaterializeNewObject flowing into a PutByOffsetHint.
>+        //
>+        // We could also add this rule:
>+        //
>+        // - If all of the Upsilons of a Phi have a MaterializeNewObject that isn't used by anyone
>+        //   else, then replace the Phi with the MaterializeNewObject.
>+        //
>+        //   FIXME: Implement this. Note that this totally doable but it requires some gnarly
>+        //   code, and to be effective the pruner needs to be aware of it. Currently any Upsilon
>+        //   is considered to be an escape even by the pruner, so it's unlikely that we'll see
>+        //   many cases of Phi over Materializations.
>+        //   https://bugs.webkit.org/show_bug.cgi?id=136927
>+        
>+        if (!performSinking())
>+            return false;
>+        
>+        while (performSinking()) { }
>+        
>+        if (verbose) {
>+            dataLog("Graph after sinking:\n");
>+            m_graph.dump();
>+        }
>+        
>+        return true;
>+    }
>+
>+private:
>+    bool performSinking()
>+    {
>+        m_graph.computeRefCounts();
>+        performLivenessAnalysis(m_graph);
>+        performOSRAvailabilityAnalysis(m_graph);
>+        
>+        CString graphBeforeSinking;
>+        if (Options::verboseValidationFailure() && Options::validateGraphAtEachPhase()) {
>+            StringPrintStream out;
>+            m_graph.dump(out);
>+            graphBeforeSinking = out.toCString();
>+        }
>+        
>+        if (verbose) {
>+            dataLog("Graph before sinking:\n");
>+            m_graph.dump();
>+        }
>+        
>+        determineMaterializationPoints();
>+        if (m_sinkCandidates.isEmpty())
>+            return false;
>+        
>+        // At this point we are committed to sinking the sinking candidates.
>+        placeMaterializationPoints();
>+        lowerNonReadingOperationsOnPhantomAllocations();
>+        promoteSunkenFields();
>+        
>+        if (Options::validateGraphAtEachPhase())
>+            validate(m_graph, DumpGraph, graphBeforeSinking);
>+        
>+        if (verbose)
>+            dataLog("Sinking iteration changed the graph.\n");
>+        return true;
>+    }
>+    
>+    void determineMaterializationPoints()
>+    {
>+        // The premise of this pass is that if there exists a point in the program where some
>+        // path from a phantom allocation site to that point causes materialization, then *all*
>+        // paths cause materialization. This should mean that there are never any redundant
>+        // materializations.
>+        
>+        m_sinkCandidates.clear();
>+        m_edgeToMaterializationPoint.clear();
>+        
>+        BlockMap<HashMap<Node*, bool>> materializedAtHead(m_graph);
>+        BlockMap<HashMap<Node*, bool>> materializedAtTail(m_graph);
>+        
>+        bool changed;
>+        do {
>+            if (verbose)
>+                dataLog("Doing iteration of materialization point placement.\n");
>+            changed = false;
>+            for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
>+                HashMap<Node*, bool> materialized = materializedAtHead[block];
>+                for (Node* node : *block) {
>+                    handleNode(
>+                        node,
>+                        [&] () {
>+                            materialized.add(node, false);
>+                        },
>+                        [&] (Node* escapee) {
>+                            auto iter = materialized.find(escapee);
>+                            if (iter != materialized.end())
>+                                iter->value = true;
>+                        });
>+                }
>+                
>+                if (verbose)
>+                    dataLog("    Materialized at tail of ", pointerDump(block), ": ", mapDump(materialized), "\n");
>+                
>+                if (materialized == materializedAtTail[block])
>+                    continue;
>+                
>+                materializedAtTail[block] = materialized;
>+                changed = true;
>+                
>+                // Only propagate things to our successors if they are alive in all successors.
>+                // So, we prune materialized-at-tail to only include things that are live.
>+                Vector<Node*> toRemove;
>+                for (auto pair : materialized) {
>+                    if (!block->ssa->liveAtTail.contains(pair.key))
>+                        toRemove.append(pair.key);
>+                }
>+                for (Node* key : toRemove)
>+                    materialized.remove(key);
>+                
>+                for (BasicBlock* successorBlock : block->successors()) {
>+                    for (auto pair : materialized) {
>+                        materializedAtHead[successorBlock].add(
>+                            pair.key, false).iterator->value |= pair.value;
>+                    }
>+                }
>+            }
>+        } while (changed);
>+        
>+        // Determine the sink candidates. Broadly, a sink candidate is a node that handleNode()
>+        // believes is sinkable, and one of the following is true:
>+        //
>+        // 1) There exists a basic block with only backward outgoing edges (or no outgoing edges)
>+        //    in which the node wasn't materialized. This is meant to catch effectively-infinite
>+        //    loops in which we don't need to have allocated the object.
>+        //
>+        // 2) There exists a basic block at the tail of which the node is not materialized and the
>+        //    node is dead.
>+        //
>+        // 3) The sum of execution counts of the materializations is less than the sum of
>+        //    execution counts of the original node.
>+        //
>+        // We currently implement only rule #2.
>+        // FIXME: Implement the two other rules.
>+        // https://bugs.webkit.org/show_bug.cgi?id=137073 (rule #1)
>+        // https://bugs.webkit.org/show_bug.cgi?id=137074 (rule #3)
>+        
>+        for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
>+            for (auto pair : materializedAtTail[block]) {
>+                if (pair.value)
>+                    continue; // It was materialized.
>+                
>+                if (block->ssa->liveAtTail.contains(pair.key))
>+                    continue; // It might still get materialized in all of the successors.
>+                
>+                // We know that it died in this block and it wasn't materialized. That means that
>+                // if we sink this allocation, then *this* will be a path along which we never
>+                // have to allocate. Profit!
>+                m_sinkCandidates.add(pair.key);
>+            }
>+        }
>+        
>+        if (m_sinkCandidates.isEmpty())
>+            return;
>+        
>+        // A materialization edge exists at any point where a node escapes but hasn't been
>+        // materialized yet.
>+        //
>+        // FIXME: This can create duplicate allocations when we really only needed to perform one.
>+        // For example:
>+        //
>+        //     var o = new Object();
>+        //     if (rare) {
>+        //         if (stuff)
>+        //             call(o); // o escapes here.
>+        //         return;
>+        //     }
>+        //     // o doesn't escape down here.
>+        //
>+        // In this example, we would place a materialization point at call(o) and then we would find
>+        // ourselves having to insert another one at the implicit else case of that if statement
>+        // ('cause we've broken critical edges). We would instead really like to just have one
>+        // materialization point right at the top of the then case of "if (rare)". To do this, we can
>+        // find the LCA of the various materializations in the dom tree.
>+        // https://bugs.webkit.org/show_bug.cgi?id=137124
>+        for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
>+            HashSet<Node*> materialized;
>+            for (auto pair : materializedAtHead[block]) {
>+                if (pair.value && m_sinkCandidates.contains(pair.key))
>+                    materialized.add(pair.key);
>+            }
>+            
>+            for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) {
>+                Node* node = block->at(nodeIndex);
>+                
>+                handleNode(
>+                    node,
>+                    [&] () { },
>+                    [&] (Node* escapee) {
>+                        if (!m_sinkCandidates.contains(escapee))
>+                            return;
>+                        
>+                        if (!materialized.add(escapee).isNewEntry)
>+                            return;
>+                        
>+                        Node* materialize = createMaterialize(escapee, node->origin);
>+                        if (verbose)
>+                            dataLog("Adding materialization point: ", node, "->", escapee, " = ", materialize, "\n");
>+                        m_edgeToMaterializationPoint.add(
>+                            std::make_pair(node, escapee), materialize);
>+                    });
>+            }
>+        }
>+    }
>+    
>+    void placeMaterializationPoints()
>+    {
>+        m_ssaCalculator.reset();
>+        
>+        HashMap<Node*, SSACalculator::Variable*> nodeToVariable;
>+        Vector<Node*> indexToNode;
>+        
>+        for (Node* node : m_sinkCandidates) {
>+            SSACalculator::Variable* variable = m_ssaCalculator.newVariable();
>+            nodeToVariable.add(node, variable);
>+            ASSERT(indexToNode.size() == variable->index());
>+            indexToNode.append(node);
>+        }
>+        
>+        for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
>+            for (Node* node : *block) {
>+                if (SSACalculator::Variable* variable = nodeToVariable.get(node))
>+                    m_ssaCalculator.newDef(variable, block, node);
>+                
>+                m_graph.doToChildren(
>+                    node,
>+                    [&] (Edge edge) {
>+                        Node* materialize =
>+                            m_edgeToMaterializationPoint.get(std::make_pair(node, edge.node()));
>+                        if (!materialize)
>+                            return;
>+                        
>+                        m_ssaCalculator.newDef(
>+                            nodeToVariable.get(edge.node()), block, materialize);
>+                    });
>+            }
>+        }
>+        
>+        m_ssaCalculator.computePhis(
>+            [&] (SSACalculator::Variable* variable, BasicBlock* block) -> Node* {
>+                Node* allocation = indexToNode[variable->index()];
>+                if (!block->ssa->liveAtHead.contains(allocation))
>+                    return nullptr;
>+                
>+                Node* phiNode = m_graph.addNode(allocation->prediction(), Phi, NodeOrigin());
>+                phiNode->mergeFlags(NodeResultJS);
>+                return phiNode;
>+            });
>+        
>+        // Place Phis in the right places. Replace all uses of any allocation with the appropriate
>+        // materialization. Create the appropriate Upsilon nodes.
>+        LocalOSRAvailabilityCalculator availabilityCalculator;
>+        for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
>+            HashMap<Node*, Node*> mapping;
>+            
>+            for (Node* candidate : block->ssa->liveAtHead) {
>+                SSACalculator::Variable* variable = nodeToVariable.get(candidate);
>+                if (!variable)
>+                    continue;
>+                
>+                SSACalculator::Def* def = m_ssaCalculator.reachingDefAtHead(block, variable);
>+                if (!def)
>+                    continue;
>+                
>+                mapping.set(indexToNode[variable->index()], def->value());
>+            }
>+            
>+            availabilityCalculator.beginBlock(block);
>+            for (SSACalculator::Def* phiDef : m_ssaCalculator.phisForBlock(block)) {
>+                m_insertionSet.insert(0, phiDef->value());
>+                
>+                Node* originalNode = indexToNode[phiDef->variable()->index()];
>+                insertOSRHintsForUpdate(
>+                    m_insertionSet, 0, NodeOrigin(), availabilityCalculator.m_availability,
>+                    originalNode, phiDef->value());
>+
>+                mapping.set(originalNode, phiDef->value());
>+            }
>+            
>+            for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) {
>+                Node* node = block->at(nodeIndex);
>+
>+                m_graph.doToChildren(
>+                    node,
>+                    [&] (Edge edge) {
>+                        Node* materialize = m_edgeToMaterializationPoint.get(
>+                            std::make_pair(node, edge.node()));
>+                        if (materialize) {
>+                            m_insertionSet.insert(nodeIndex, materialize);
>+                            insertOSRHintsForUpdate(
>+                                m_insertionSet, nodeIndex, node->origin,
>+                                availabilityCalculator.m_availability, edge.node(), materialize);
>+                            mapping.set(edge.node(), materialize);
>+                        }
>+                    });
>+
>+                availabilityCalculator.executeNode(node);
>+                
>+                m_graph.doToChildren(
>+                    node,
>+                    [&] (Edge& edge) {
>+                        if (Node* materialize = mapping.get(edge.node()))
>+                            edge.setNode(materialize);
>+                    });
>+            }
>+            
>+            size_t upsilonInsertionPoint = block->size() - 1;
>+            NodeOrigin upsilonOrigin = block->last()->origin;
>+            for (BasicBlock* successorBlock : block->successors()) {
>+                for (SSACalculator::Def* phiDef : m_ssaCalculator.phisForBlock(successorBlock)) {
>+                    Node* phiNode = phiDef->value();
>+                    SSACalculator::Variable* variable = phiDef->variable();
>+                    Node* allocation = indexToNode[variable->index()];
>+                    
>+                    Node* originalIncoming = mapping.get(allocation);
>+                    Node* incoming;
>+                    if (originalIncoming == allocation) {
>+                        // If we have a Phi that combines materializations with the original
>+                        // phantom object, then the path with the phantom object must materialize.
>+                        
>+                        incoming = createMaterialize(allocation, upsilonOrigin);
>+                        m_insertionSet.insert(upsilonInsertionPoint, incoming);
>+                        insertOSRHintsForUpdate(
>+                            m_insertionSet, upsilonInsertionPoint, upsilonOrigin,
>+                            availabilityCalculator.m_availability, originalIncoming, incoming);
>+                    } else
>+                        incoming = originalIncoming;
>+                    
>+                    Node* upsilon = m_insertionSet.insertNode(
>+                        upsilonInsertionPoint, SpecNone, Upsilon, upsilonOrigin,
>+                        OpInfo(phiNode), incoming->defaultEdge());
>+                    
>+                    if (originalIncoming == allocation) {
>+                        m_edgeToMaterializationPoint.add(
>+                            std::make_pair(upsilon, allocation), incoming);
>+                    }
>+                }
>+            }
>+            
>+            m_insertionSet.execute(block);
>+        }
>+        
>+        // At this point we have dummy materialization nodes along with edges to them. This means
>+        // that the part of the control flow graph that prefers to see actual object allocations
>+        // is completely fixed up, except for the materializations themselves.
>+    }
>+    
>+    void lowerNonReadingOperationsOnPhantomAllocations()
>+    {
>+        // Lower everything but reading operations on phantom allocations. We absolutely have to
>+        // lower all writes so as to reveal them to the SSA calculator. We cannot lower reads
>+        // because the whole point is that those go away completely.
>+        
>+        for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
>+            for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) {
>+                Node* node = block->at(nodeIndex);
>+                switch (node->op()) {
>+                case PutByOffset: {
>+                    if (m_sinkCandidates.contains(node->child2().node()))
>+                        node->convertToPutByOffsetHint();
>+                    break;
>+                }
>+                    
>+                case PutStructure: {
>+                    if (m_sinkCandidates.contains(node->child1().node())) {
>+                        Node* structure = m_insertionSet.insertConstant(
>+                            nodeIndex, node->origin, JSValue(node->transition()->next));
>+                        node->convertToPutStructureHint(structure);
>+                    }
>+                    break;
>+                }
>+                    
>+                case NewObject: {
>+                    if (m_sinkCandidates.contains(node)) {
>+                        Node* structure = m_insertionSet.insertConstant(
>+                            nodeIndex + 1, node->origin, JSValue(node->structure()));
>+                        m_insertionSet.insertNode(
>+                            nodeIndex + 1, SpecNone, PutStructureHint, node->origin,
>+                            Edge(node, KnownCellUse), Edge(structure, KnownCellUse));
>+                        node->convertToPhantomNewObject();
>+                    }
>+                    break;
>+                }
>+                    
>+                case MaterializeNewObject: {
>+                    if (m_sinkCandidates.contains(node)) {
>+                        m_insertionSet.insertNode(
>+                            nodeIndex + 1, SpecNone, PutStructureHint, node->origin,
>+                            Edge(node, KnownCellUse), m_graph.varArgChild(node, 0));
>+                        for (unsigned i = 0; i < node->objectMaterializationData().m_properties.size(); ++i) {
>+                            m_insertionSet.insertNode(
>+                                nodeIndex + 1, SpecNone, PutByOffsetHint, node->origin,
>+                                Edge(node, KnownCellUse), m_graph.varArgChild(node, i + 1));
>+                        }
>+                        node->convertToPhantomNewObject();
>+                    }
>+                    break;
>+                }
>+                    
>+                case StoreBarrier:
>+                case StoreBarrierWithNullCheck: {
>+                    if (m_sinkCandidates.contains(node->child1().node()))
>+                        node->convertToPhantom();
>+                    break;
>+                }
>+                    
>+                default:
>+                    break;
>+                }
>+                
>+                m_graph.doToChildren(
>+                    node,
>+                    [&] (Edge& edge) {
>+                        if (m_sinkCandidates.contains(edge.node()))
>+                            edge.setUseKind(KnownCellUse);
>+                    });
>+            }
>+            m_insertionSet.execute(block);
>+        }
>+    }
>+    
>+    void promoteSunkenFields()
>+    {
>+        // Henceforth when we encounter a materialization point, we will want to ask *who* it is
>+        // a materialization for. Invert the map to be able to answer such questions.
>+        m_materializationPointToEscapee.clear();
>+        for (auto pair : m_edgeToMaterializationPoint)
>+            m_materializationPointToEscapee.add(pair.value, pair.key.second);
>+        
>+        // Collect the set of heap locations that we will be operating over.
>+        HashSet<PromotedHeapLocation> locations;
>+        for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
>+            for (Node* node : *block) {
>+                promoteHeapAccess(
>+                    node,
>+                    [&] (PromotedHeapLocation location, Edge) {
>+                        locations.add(location);
>+                    },
>+                    [&] (PromotedHeapLocation location) {
>+                        locations.add(location);
>+                    });
>+            }
>+        }
>+        
>+        // Figure out which locations belong to which allocations.
>+        m_locationsForAllocation.clear();
>+        for (PromotedHeapLocation location : locations) {
>+            auto result = m_locationsForAllocation.add(location.base(), Vector<PromotedHeapLocation>());
>+            ASSERT(!result.iterator->value.contains(location));
>+            result.iterator->value.append(location);
>+        }
>+        
>+        // For each sunken thingy, make sure we create Bottom values for all of its fields.
>+        // Note that this has the hilarious slight inefficiency of creating redundant hints for
>+        // things that were previously materializations. This should only impact compile times and
>+        // not code quality, and it's necessary for soundness without some data structure hackage.
>+        // For example, a MaterializeNewObject that we choose to sink may have new fields added to
>+        // it conditionally. That would necessitate Bottoms.
>+        Node* bottom = nullptr;
>+        for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
>+            if (block == m_graph.block(0))
>+                bottom = m_insertionSet.insertNode(0, SpecNone, BottomValue, NodeOrigin());
>+            
>+            for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) {
>+                Node* node = block->at(nodeIndex);
>+                for (PromotedHeapLocation location : m_locationsForAllocation.get(node)) {
>+                    m_insertionSet.insert(
>+                        nodeIndex + 1, location.createHint(m_graph, node->origin, bottom));
>+                }
>+            }
>+            m_insertionSet.execute(block);
>+        }
>+
>+        m_ssaCalculator.reset();
>+
>+        // Collect the set of "variables" that we will be sinking.
>+        m_locationToVariable.clear();
>+        m_indexToLocation.clear();
>+        for (PromotedHeapLocation location : locations) {
>+            SSACalculator::Variable* variable = m_ssaCalculator.newVariable();
>+            m_locationToVariable.add(location, variable);
>+            ASSERT(m_indexToLocation.size() == variable->index());
>+            m_indexToLocation.append(location);
>+        }
>+        
>+        // Create Defs from the existing hints.
>+        for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
>+            for (Node* node : *block) {
>+                promoteHeapAccess(
>+                    node,
>+                    [&] (PromotedHeapLocation location, Edge value) {
>+                        SSACalculator::Variable* variable = m_locationToVariable.get(location);
>+                        m_ssaCalculator.newDef(variable, block, value.node());
>+                    },
>+                    [&] (PromotedHeapLocation) { });
>+            }
>+        }
>+        
>+        // OMG run the SSA calculator to create Phis!
>+        m_ssaCalculator.computePhis(
>+            [&] (SSACalculator::Variable* variable, BasicBlock* block) -> Node* {
>+                PromotedHeapLocation location = m_indexToLocation[variable->index()];
>+                if (!block->ssa->liveAtHead.contains(location.base()))
>+                    return nullptr;
>+                
>+                Node* phiNode = m_graph.addNode(SpecHeapTop, Phi, NodeOrigin());
>+                phiNode->mergeFlags(NodeResultJS);
>+                return phiNode;
>+            });
>+        
>+        // Place Phis in the right places, replace all uses of any load with the appropriate
>+        // value, and create the appropriate Upsilon nodes.
>+        m_graph.clearReplacements();
>+        for (BasicBlock* block : m_graph.blocksInPreOrder()) {
>+            // This mapping table is intended to be lazy. If something is omitted from the table,
>+            // it means that there haven't been any local stores to that promoted heap location.
>+            m_localMapping.clear();
>+            
>+            // Insert the Phi functions that we had previously created.
>+            for (SSACalculator::Def* phiDef : m_ssaCalculator.phisForBlock(block)) {
>+                PromotedHeapLocation location = m_indexToLocation[phiDef->variable()->index()];
>+                
>+                m_insertionSet.insert(
>+                    0, phiDef->value());
>+                m_insertionSet.insert(
>+                    0, location.createHint(m_graph, NodeOrigin(), phiDef->value()));
>+                m_localMapping.add(location, phiDef->value());
>+            }
>+            
>+            if (verbose)
>+                dataLog("Local mapping at ", pointerDump(block), ": ", mapDump(m_localMapping), "\n");
>+            
>+            // Process the block and replace all uses of loads with the promoted value.
>+            for (Node* node : *block) {
>+                m_graph.performSubstitution(node);
>+                
>+                if (Node* escapee = m_materializationPointToEscapee.get(node))
>+                    populateMaterialize(block, node, escapee);
>+                
>+                promoteHeapAccess(
>+                    node,
>+                    [&] (PromotedHeapLocation location, Edge value) {
>+                        m_localMapping.set(location, value.node());
>+                    },
>+                    [&] (PromotedHeapLocation location) {
>+                        node->replaceWith(resolve(block, location));
>+                    });
>+            }
>+            
>+            // Gotta drop some Upsilons.
>+            size_t upsilonInsertionPoint = block->size() - 1;
>+            NodeOrigin upsilonOrigin = block->last()->origin;
>+            for (BasicBlock* successorBlock : block->successors()) {
>+                for (SSACalculator::Def* phiDef : m_ssaCalculator.phisForBlock(successorBlock)) {
>+                    Node* phiNode = phiDef->value();
>+                    SSACalculator::Variable* variable = phiDef->variable();
>+                    PromotedHeapLocation location = m_indexToLocation[variable->index()];
>+                    Node* incoming = resolve(block, location);
>+                    
>+                    m_insertionSet.insertNode(
>+                        upsilonInsertionPoint, SpecNone, Upsilon, upsilonOrigin,
>+                        OpInfo(phiNode), incoming->defaultEdge());
>+                }
>+            }
>+            
>+            m_insertionSet.execute(block);
>+        }
>+    }
>+    
>+    Node* resolve(BasicBlock* block, PromotedHeapLocation location)
>+    {
>+        if (Node* result = m_localMapping.get(location))
>+            return result;
>+        
>+        // This implies that there is no local mapping. Find a non-local mapping.
>+        SSACalculator::Def* def = m_ssaCalculator.nonLocalReachingDef(
>+            block, m_locationToVariable.get(location));
>+        ASSERT(def);
>+        ASSERT(def->value());
>+        m_localMapping.add(location, def->value());
>+        return def->value();
>+    }
>+
>+    template<typename SinkCandidateFunctor, typename EscapeFunctor>
>+    void handleNode(
>+        Node* node,
>+        const SinkCandidateFunctor& sinkCandidate,
>+        const EscapeFunctor& escape)
>+    {
>+        switch (node->op()) {
>+        case NewObject:
>+        case MaterializeNewObject:
>+            sinkCandidate();
>+            break;
>+            
>+        case CheckStructure:
>+        case GetByOffset:
>+        case MultiGetByOffset:
>+        case PutStructure:
>+        case GetGetterSetterByOffset:
>+        case MovHint:
>+        case Phantom:
>+        case Check:
>+        case HardPhantom:
>+        case StoreBarrier:
>+        case StoreBarrierWithNullCheck:
>+        case PutByOffsetHint:
>+            break;
>+            
>+        case PutByOffset:
>+            escape(node->child3().node());
>+            break;
>+            
>+        case MultiPutByOffset:
>+            // FIXME: In the future we should be able to handle this. It's just a matter of
>+            // building the appropriate *Hint variant of this instruction, along with a
>+            // PhantomStructureSelect node - since this transforms the Structure in a conditional
>+            // way.
>+            // https://bugs.webkit.org/show_bug.cgi?id=136924
>+            escape(node->child1().node());
>+            escape(node->child2().node());
>+            break;
>+
>+        default:
>+            m_graph.doToChildren(
>+                node,
>+                [&escape] (Edge edge) {
>+                    escape(edge.node());
>+                });
>+            break;
>+        }
>+    }
>+    
>+    Node* createMaterialize(Node* escapee, const NodeOrigin whereOrigin)
>+    {
>+        switch (escapee->op()) {
>+        case NewObject:
>+        case MaterializeNewObject: {
>+            ObjectMaterializationData* data = m_graph.m_objectMaterializationData.add();
>+            
>+            Node* result = m_graph.addNode(
>+                escapee->prediction(), Node::VarArg, MaterializeNewObject,
>+                NodeOrigin(
>+                    escapee->origin.semantic,
>+                    whereOrigin.forExit),
>+                OpInfo(data), OpInfo(), 0, 0);
>+            return result;
>+        }
>+            
>+        default:
>+            DFG_CRASH(m_graph, escapee, "Bad escapee op");
>+            return nullptr;
>+        }
>+    }
>+    
>+    void populateMaterialize(BasicBlock* block, Node* node, Node* escapee)
>+    {
>+        switch (node->op()) {
>+        case MaterializeNewObject: {
>+            ObjectMaterializationData& data = node->objectMaterializationData();
>+            unsigned firstChild = m_graph.m_varArgChildren.size();
>+            
>+            Vector<PromotedHeapLocation> locations = m_locationsForAllocation.get(escapee);
>+            
>+            PromotedHeapLocation structure(StructurePLoc, escapee);
>+            ASSERT(locations.contains(structure));
>+            
>+            m_graph.m_varArgChildren.append(Edge(resolve(block, structure), KnownCellUse));
>+            
>+            for (unsigned i = 0; i < locations.size(); ++i) {
>+                switch (locations[i].kind()) {
>+                case StructurePLoc: {
>+                    ASSERT(locations[i] == structure);
>+                    break;
>+                }
>+                    
>+                case NamedPropertyPLoc: {
>+                    Node* value = resolve(block, locations[i]);
>+                    if (value->op() == BottomValue) {
>+                        // We can skip Bottoms entirely.
>+                        break;
>+                    }
>+                    
>+                    data.m_properties.append(PhantomPropertyValue(locations[i].info()));
>+                    m_graph.m_varArgChildren.append(value);
>+                    break;
>+                }
>+                    
>+                default:
>+                    DFG_CRASH(m_graph, node, "Bad location kind");
>+                }
>+            }
>+            
>+            node->children = AdjacencyList(
>+                AdjacencyList::Variable,
>+                firstChild, m_graph.m_varArgChildren.size() - firstChild);
>+            break;
>+        }
>+            
>+        default:
>+            DFG_CRASH(m_graph, node, "Bad materialize op");
>+            break;
>+        }
>+    }
>+    
>+    SSACalculator m_ssaCalculator;
>+    HashSet<Node*> m_sinkCandidates;
>+    HashMap<std::pair<Node*, Node*>, Node*> m_edgeToMaterializationPoint;
>+    HashMap<Node*, Node*> m_materializationPointToEscapee;
>+    HashMap<Node*, Vector<PromotedHeapLocation>> m_locationsForAllocation;
>+    HashMap<PromotedHeapLocation, SSACalculator::Variable*> m_locationToVariable;
>+    Vector<PromotedHeapLocation> m_indexToLocation;
>+    HashMap<PromotedHeapLocation, Node*> m_localMapping;
>+    InsertionSet m_insertionSet;
>+};
>+    
>+bool performObjectAllocationSinking(Graph& graph)
>+{
>+    SamplingRegion samplingRegion("DFG Object Allocation Sinking Phase");
>+    return runPhase<ObjectAllocationSinkingPhase>(graph);
>+}
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>Index: Source/JavaScriptCore/dfg/DFGObjectAllocationSinkingPhase.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGObjectAllocationSinkingPhase.h	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGObjectAllocationSinkingPhase.h	(working copy)
>@@ -0,0 +1,47 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef DFGObjectAllocationSinkingPhase_h
>+#define DFGObjectAllocationSinkingPhase_h
>+
>+#if ENABLE(DFG_JIT)
>+
>+namespace JSC { namespace DFG {
>+
>+class Graph;
>+
>+// Sinks object allocations down to their uses. This will sink the allocations over OSR exits, by
>+// replacing all stores to those objects with store hints so that OSR exit can materialize the
>+// object. This may sink allocations past returns, creating control flow paths along which the
>+// objects are not allocated at all. Replaces all uses of the objects' fields with SSA data flow.
>+
>+bool performObjectAllocationSinking(Graph&);
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>+#endif // DFGObjectAllocationSinkingPhase_h
>+
>Index: Source/JavaScriptCore/dfg/DFGObjectMaterializationData.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGObjectMaterializationData.cpp	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGObjectMaterializationData.cpp	(working copy)
>@@ -0,0 +1,63 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "DFGObjectMaterializationData.h"
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include <wtf/ListDump.h>
>+
>+namespace JSC { namespace DFG {
>+
>+void PhantomPropertyValue::dump(PrintStream& out) const
>+{
>+    out.print("id", m_identifierNumber);
>+}
>+
>+void ObjectMaterializationData::dump(PrintStream& out) const
>+{
>+    out.print("[", listDump(m_properties), "]");
>+}
>+
>+float ObjectMaterializationData::oneWaySimilarityScore(
>+    const ObjectMaterializationData& other) const
>+{
>+    unsigned numHits = 0;
>+    for (PhantomPropertyValue value : m_properties) {
>+        if (other.m_properties.contains(value))
>+            numHits++;
>+    }
>+    return static_cast<float>(numHits) / static_cast<float>(m_properties.size());
>+}
>+
>+float ObjectMaterializationData::similarityScore(const ObjectMaterializationData& other) const
>+{
>+    return std::min(oneWaySimilarityScore(other), other.oneWaySimilarityScore(*this));
>+}
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>Index: Source/JavaScriptCore/dfg/DFGObjectMaterializationData.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGObjectMaterializationData.h	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGObjectMaterializationData.h	(working copy)
>@@ -0,0 +1,77 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef DFGObjectMaterializationData_h
>+#define DFGObjectMaterializationData_h
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include <limits.h>
>+#include <wtf/MathExtras.h>
>+#include <wtf/PrintStream.h>
>+#include <wtf/Vector.h>
>+
>+namespace JSC { namespace DFG {
>+
>+struct PhantomPropertyValue {
>+    PhantomPropertyValue()
>+        : m_identifierNumber(UINT_MAX)
>+    {
>+    }
>+    
>+    PhantomPropertyValue(unsigned identifierNumber)
>+        : m_identifierNumber(identifierNumber)
>+    {
>+    }
>+    
>+    unsigned m_identifierNumber;
>+    
>+    bool operator==(const PhantomPropertyValue& other) const
>+    {
>+        return m_identifierNumber == other.m_identifierNumber;
>+    }
>+    
>+    void dump(PrintStream&) const;
>+};
>+
>+struct ObjectMaterializationData {
>+    // Determines the meaning of the passed nodes.
>+    Vector<PhantomPropertyValue> m_properties;
>+    
>+    void dump(PrintStream&) const;
>+    
>+    // The fraction of my properties that the other data has.
>+    float oneWaySimilarityScore(const ObjectMaterializationData&) const;
>+    
>+    // The minimum of the two possible one-way scores.
>+    float similarityScore(const ObjectMaterializationData&) const;
>+};
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>+#endif // DFGObjectMaterializationData_h
>+
>Index: Source/JavaScriptCore/dfg/DFGPhantomCanonicalizationPhase.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPhantomCanonicalizationPhase.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGPhantomCanonicalizationPhase.cpp	(working copy)
>@@ -52,18 +52,7 @@ public:
>         ASSERT(m_graph.m_form == SSA);
>         
>         m_graph.clearFlagsOnAllNodes(NodeNeedsPhantom | NodeNeedsHardPhantom | NodeRelevantToOSR);
>-        
>-        for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) {
>-            BasicBlock* block = m_graph.block(blockIndex);
>-            if (!block)
>-                continue;
>-            
>-            for (unsigned i = block->size(); i--;) {
>-                Node* node = block->at(i);
>-                if (node->op() == MovHint)
>-                    node->child1()->mergeFlags(NodeRelevantToOSR);
>-            }
>-        }
>+        m_graph.mergeRelevantToOSR();
>         
>         for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) {
>             BasicBlock* block = m_graph.block(blockIndex);
>Index: Source/JavaScriptCore/dfg/DFGPhantomRemovalPhase.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPhantomRemovalPhase.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGPhantomRemovalPhase.cpp	(working copy)
>@@ -74,17 +74,7 @@ public:
>             }
>         }
>         
>-        for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) {
>-            BasicBlock* block = m_graph.block(blockIndex);
>-            if (!block)
>-                continue;
>-            
>-            for (unsigned i = block->size(); i--;) {
>-                Node* node = block->at(i);
>-                if (node->op() == MovHint)
>-                    node->child1()->mergeFlags(NodeRelevantToOSR);
>-            }
>-        }
>+        m_graph.mergeRelevantToOSR();
>         
>         for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) {
>             BasicBlock* block = m_graph.block(blockIndex);
>Index: Source/JavaScriptCore/dfg/DFGPhiChildren.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPhiChildren.cpp	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGPhiChildren.cpp	(working copy)
>@@ -0,0 +1,64 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "DFGPhiChildren.h"
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGGraph.h"
>+
>+namespace JSC { namespace DFG {
>+
>+PhiChildren::PhiChildren()
>+{
>+}
>+
>+PhiChildren::PhiChildren(Graph& graph)
>+{
>+    for (BasicBlock* block : graph.blocksInNaturalOrder()) {
>+        for (Node* node : *block) {
>+            if (node->op() != Upsilon)
>+                continue;
>+            
>+            m_children.add(node->phi(), List()).iterator->value.append(node);
>+        }
>+    }
>+}
>+
>+PhiChildren::~PhiChildren()
>+{
>+}
>+
>+const PhiChildren::List& PhiChildren::upsilonsOf(Node* node) const
>+{
>+    ASSERT(node->op() == Phi);
>+    return m_children.find(node)->value;
>+}
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>Index: Source/JavaScriptCore/dfg/DFGPhiChildren.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPhiChildren.h	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGPhiChildren.h	(working copy)
>@@ -0,0 +1,92 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef DFGPhiChildren_h
>+#define DFGPhiChildren_h
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGNode.h"
>+#include <wtf/HashSet.h>
>+#include <wtf/Vector.h>
>+
>+namespace JSC { namespace DFG {
>+
>+class Graph;
>+
>+class PhiChildren {
>+public:
>+    typedef Vector<Node*, 3> List;
>+    
>+    PhiChildren();
>+    PhiChildren(Graph&);
>+    ~PhiChildren();
>+    
>+    // The list of Upsilons that point to the children of the Phi.
>+    const List& upsilonsOf(Node*) const;
>+    
>+    template<typename Functor>
>+    void forAllIncomingValues(Node* node, const Functor& functor)
>+    {
>+        for (Node* upsilon : upsilonsOf(node))
>+            functor(upsilon->child1().node());
>+    }
>+    
>+    // This walks the Phi graph.
>+    template<typename Functor>
>+    void forAllTransitiveIncomingValues(Node* node, const Functor& functor)
>+    {
>+        if (node->op() != Phi) {
>+            functor(node);
>+            return;
>+        }
>+        HashSet<Node*> seen;
>+        Vector<Node*> worklist;
>+        seen.add(node);
>+        worklist.append(node);
>+        while (!worklist.isEmpty()) {
>+            Node* currentNode = worklist.takeLast();
>+            forAllIncomingValues(
>+                currentNode,
>+                [&] (Node* incomingNode) {
>+                    if (incomingNode->op() == Phi) {
>+                        if (seen.add(incomingNode).isNewEntry)
>+                            worklist.append(incomingNode);
>+                    } else
>+                        functor(incomingNode);
>+                });
>+        }
>+    }
>+    
>+private:
>+    HashMap<Node*, List> m_children;
>+};
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>+#endif // DFGPhiChildren_h
>+
>Index: Source/JavaScriptCore/dfg/DFGPlan.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPlan.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGPlan.cpp	(working copy)
>@@ -49,6 +49,7 @@
> #include "DFGLoopPreHeaderCreationPhase.h"
> #include "DFGOSRAvailabilityAnalysisPhase.h"
> #include "DFGOSREntrypointCreationPhase.h"
>+#include "DFGObjectAllocationSinkingPhase.h"
> #include "DFGPhantomCanonicalizationPhase.h"
> #include "DFGPhantomRemovalPhase.h"
> #include "DFGPredictionInjectionPhase.h"
>@@ -277,6 +278,7 @@ Plan::CompilationPath Plan::compileInThr
>     if (validationEnabled()) {
>         dfg.m_dominators.computeIfNecessary(dfg);
>         dfg.m_naturalLoops.computeIfNecessary(dfg);
>+        dfg.m_prePostNumbering.computeIfNecessary(dfg);
>     }
> 
>     switch (mode) {
>@@ -325,11 +327,16 @@ Plan::CompilationPath Plan::compileInThr
>         performCFA(dfg);
>         performConstantFolding(dfg);
>         performPhantomCanonicalization(dfg); // Reduce the graph size a lot.
>-        if (performStrengthReduction(dfg)) {
>+        changed = false;
>+        changed |= performStrengthReduction(dfg);
>+        changed |= performCriticalEdgeBreaking(dfg);
>+        changed |= performObjectAllocationSinking(dfg);
>+        if (changed) {
>             // State-at-tail and state-at-head will be invalid if we did strength reduction since
>             // it might increase live ranges.
>             performLivenessAnalysis(dfg);
>             performCFA(dfg);
>+            performConstantFolding(dfg);
>         }
>         performLICM(dfg);
>         performPhantomCanonicalization(dfg);
>Index: Source/JavaScriptCore/dfg/DFGPrePostNumbering.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPrePostNumbering.cpp	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGPrePostNumbering.cpp	(working copy)
>@@ -0,0 +1,89 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "DFGPrePostNumbering.h"
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGBlockMapInlines.h"
>+#include "DFGBlockWorklist.h"
>+#include "DFGGraph.h"
>+
>+namespace JSC { namespace DFG {
>+
>+PrePostNumbering::PrePostNumbering() { }
>+PrePostNumbering::~PrePostNumbering() { }
>+
>+void PrePostNumbering::compute(Graph& graph)
>+{
>+    m_map = BlockMap<Numbering>(graph);
>+    
>+    PostOrderBlockWorklist worklist;
>+    worklist.push(graph.block(0));
>+    unsigned nextPreNumber = 0;
>+    unsigned nextPostNumber = 0;
>+    while (BlockWithOrder item = worklist.pop()) {
>+        switch (item.order) {
>+        case PreOrder:
>+            m_map[item.block].m_preNumber = nextPreNumber++;
>+            worklist.pushPost(item.block);
>+            for (BasicBlock* successor : item.block->successors())
>+                worklist.push(successor);
>+            break;
>+        case PostOrder:
>+            m_map[item.block].m_postNumber = nextPostNumber++;
>+            break;
>+        }
>+    }
>+}
>+
>+} } // namespace JSC::DFG
>+
>+namespace WTF {
>+
>+using namespace JSC::DFG;
>+
>+void printInternal(PrintStream& out, EdgeKind kind)
>+{
>+    switch (kind) {
>+    case ForwardEdge:
>+        out.print("ForwardEdge");
>+        return;
>+    case CrossEdge:
>+        out.print("CrossEdge");
>+        return;
>+    case BackEdge:
>+        out.print("BackEdge");
>+        return;
>+    }
>+    
>+    RELEASE_ASSERT_NOT_REACHED();
>+}
>+
>+} // namespace WTF
>+
>+#endif // ENABLE(DFG_JIT)
>+
>Index: Source/JavaScriptCore/dfg/DFGPrePostNumbering.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPrePostNumbering.h	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGPrePostNumbering.h	(working copy)
>@@ -0,0 +1,108 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef DFGPrePostNumbering_h
>+#define DFGPrePostNumbering_h
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGAnalysis.h"
>+#include "DFGBasicBlock.h"
>+#include "DFGBlockMap.h"
>+
>+namespace JSC { namespace DFG {
>+
>+enum EdgeKind {
>+    ForwardEdge,
>+    CrossEdge,
>+    BackEdge
>+};
>+
>+class PrePostNumbering : public Analysis<PrePostNumbering> {
>+public:
>+    PrePostNumbering();
>+    ~PrePostNumbering();
>+
>+    void compute(Graph&);
>+    
>+    unsigned preNumber(BasicBlock* block) const { return m_map[block].m_preNumber; }
>+    unsigned postNumber(BasicBlock* block) const { return m_map[block].m_postNumber; }
>+    
>+    // Is from a strict ancestor of to?
>+    bool isStrictAncestorOf(BasicBlock* from, BasicBlock* to) const
>+    {
>+        return preNumber(from) < preNumber(to)
>+            && postNumber(from) > postNumber(to);
>+    }
>+    
>+    bool isAncestorOf(BasicBlock* from, BasicBlock* to) const
>+    {
>+        return from == to || isStrictAncestorOf(from, to);
>+    }
>+    
>+    bool isStrictDescendantOf(BasicBlock* from, BasicBlock* to) const
>+    {
>+        return isStrictAncestorOf(to, from);
>+    }
>+    
>+    bool isDescendantOf(BasicBlock* from, BasicBlock* to) const
>+    {
>+        return isAncestorOf(to, from);
>+    }
>+    
>+    // This will give a bogus answer if there is actually no such edge. If you want to determine
>+    // if there is any such edge, you have to do it yourself.
>+    EdgeKind edgeKind(BasicBlock* from, BasicBlock* to) const
>+    {
>+        if (isStrictDescendantOf(to, from))
>+            return ForwardEdge;
>+        
>+        if (isAncestorOf(to, from))
>+            return BackEdge;
>+        
>+        return CrossEdge;
>+    }
>+    
>+private:
>+    struct Numbering {
>+        unsigned m_preNumber;
>+        unsigned m_postNumber;
>+    };
>+    
>+    BlockMap<Numbering> m_map;
>+};
>+
>+} } // namespace JSC::DFG
>+
>+namespace WTF {
>+
>+void printInternal(PrintStream&, JSC::DFG::EdgeKind);
>+
>+} // namespace WTF
>+
>+#endif // ENABLE(DFG_JIT)
>+
>+#endif // DFGPrePostNumbering_h
>+
>Index: Source/JavaScriptCore/dfg/DFGPredictionPropagationPhase.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPredictionPropagationPhase.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGPredictionPropagationPhase.cpp	(working copy)
>@@ -560,7 +560,12 @@ private:
>         case DoubleConstant:
>         case Int52Constant:
>         case Identity:
>-        case BooleanToNumber: {
>+        case BooleanToNumber:
>+        case PhantomNewObject:
>+        case PutByOffsetHint:
>+        case CheckStructureImmediate:
>+        case PutStructureHint:
>+        case MaterializeNewObject: {
>             // This node should never be visible at this stage of compilation. It is
>             // inserted by fixup(), which follows this phase.
>             RELEASE_ASSERT_NOT_REACHED();
>Index: Source/JavaScriptCore/dfg/DFGPromoteHeapAccess.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPromoteHeapAccess.h	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGPromoteHeapAccess.h	(working copy)
>@@ -0,0 +1,90 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef DFGPromoteHeapAccess_h
>+#define DFGPromoteHeapAccess_h
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGNode.h"
>+#include "DFGPromotedHeapLocation.h"
>+
>+namespace JSC { namespace DFG {
>+
>+// Note that the write functor is really the useful thing here. The read functor is only useful
>+// for the object allocation sinking phase.
>+template<typename WriteFunctor, typename ReadFunctor>
>+void promoteHeapAccess(Node* node, const WriteFunctor& write, const ReadFunctor& read)
>+{
>+    switch (node->op()) {
>+    case CheckStructure: {
>+        if (node->child1()->isPhantomObjectAllocation())
>+            read(PromotedHeapLocation(StructurePLoc, node->child1()));
>+        break;
>+    }
>+    
>+    case GetByOffset:
>+    case GetGetterSetterByOffset: {
>+        if (node->child2()->isPhantomObjectAllocation()) {
>+            unsigned identifierNumber = node->storageAccessData().identifierNumber;
>+            read(PromotedHeapLocation(NamedPropertyPLoc, node->child2(), identifierNumber));
>+        }
>+        break;
>+    }
>+
>+    case MultiGetByOffset: {
>+        if (node->child1()->isPhantomObjectAllocation()) {
>+            unsigned identifierNumber = node->multiGetByOffsetData().identifierNumber;
>+            read(PromotedHeapLocation(NamedPropertyPLoc, node->child1(), identifierNumber));
>+        }
>+        break;
>+    }
>+
>+    case PutStructureHint: {
>+        ASSERT(node->child1()->isPhantomObjectAllocation());
>+        write(PromotedHeapLocation(StructurePLoc, node->child1()), node->child2());
>+        break;
>+    }
>+
>+    case PutByOffsetHint: {
>+        ASSERT(node->child1()->isPhantomObjectAllocation());
>+        unsigned identifierNumber = node->identifierNumber();
>+        write(
>+            PromotedHeapLocation(NamedPropertyPLoc, node->child1(), identifierNumber),
>+            node->child2());
>+        break;
>+    }
>+
>+    default:
>+        break;
>+    }
>+}
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(DFG_JIT)
>+
>+#endif // DFGPromoteHeapAccess_h
>+
>Index: Source/JavaScriptCore/dfg/DFGPromotedHeapLocation.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPromotedHeapLocation.cpp	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGPromotedHeapLocation.cpp	(working copy)
>@@ -0,0 +1,95 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "DFGPromotedHeapLocation.h"
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGGraph.h"
>+#include "JSCInlines.h"
>+
>+namespace JSC { namespace DFG {
>+
>+void PromotedLocationDescriptor::dump(PrintStream& out) const
>+{
>+    out.print(m_kind, "(", m_info, ")");
>+}
>+
>+Node* PromotedHeapLocation::createHint(Graph& graph, NodeOrigin origin, Node* value)
>+{
>+    switch (kind()) {
>+    case StructurePLoc:
>+        return graph.addNode(
>+            SpecNone, PutStructureHint, origin,
>+            Edge(base(), KnownCellUse), Edge(value, KnownCellUse));
>+        
>+    case NamedPropertyPLoc:
>+        return graph.addNode(
>+            SpecNone, PutByOffsetHint, origin,
>+            OpInfo(info()), Edge(base(), KnownCellUse), Edge(value, UntypedUse));
>+        
>+    case InvalidPromotedLocationKind:
>+        return nullptr;
>+    }
>+    
>+    RELEASE_ASSERT_NOT_REACHED();
>+    return nullptr;
>+}
>+
>+void PromotedHeapLocation::dump(PrintStream& out) const
>+{
>+    out.print(kind(), "(", m_base, ", ", info(), ")");
>+}
>+
>+} } // namespace JSC::DFG
>+
>+namespace WTF {
>+
>+using namespace JSC::DFG;
>+
>+void printInternal(PrintStream& out, PromotedLocationKind kind)
>+{
>+    switch (kind) {
>+    case InvalidPromotedLocationKind:
>+        out.print("InvalidPromotedLocationKind");
>+        return;
>+        
>+    case StructurePLoc:
>+        out.print("StructurePLoc");
>+        return;
>+        
>+    case NamedPropertyPLoc:
>+        out.print("NamedPropertyPLoc");
>+        return;
>+    }
>+    
>+    RELEASE_ASSERT_NOT_REACHED();
>+}
>+
>+} // namespace WTF;
>+
>+#endif // ENABLE(DFG_JIT)
>+
>Index: Source/JavaScriptCore/dfg/DFGPromotedHeapLocation.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGPromotedHeapLocation.h	(revision 0)
>+++ Source/JavaScriptCore/dfg/DFGPromotedHeapLocation.h	(working copy)
>@@ -0,0 +1,172 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef DFGPromotedHeapLocation_h
>+#define DFGPromotedHeapLocation_h
>+
>+#if ENABLE(DFG_JIT)
>+
>+#include "DFGNode.h"
>+#include <wtf/PrintStream.h>
>+
>+namespace JSC { namespace DFG {
>+
>+enum PromotedLocationKind {
>+    InvalidPromotedLocationKind,
>+    
>+    StructurePLoc,
>+    NamedPropertyPLoc
>+};
>+
>+class PromotedLocationDescriptor {
>+public:
>+    PromotedLocationDescriptor(
>+        PromotedLocationKind kind = InvalidPromotedLocationKind, unsigned info = 0)
>+        : m_kind(kind)
>+        , m_info(info)
>+    {
>+    }
>+    
>+    bool operator!() const { return m_kind == InvalidPromotedLocationKind; }
>+    
>+    PromotedLocationKind kind() const { return m_kind; }
>+    unsigned info() const { return m_info; }
>+    
>+    unsigned hash() const
>+    {
>+        return m_kind + m_info;
>+    }
>+    
>+    bool operator==(const PromotedLocationDescriptor& other) const
>+    {
>+        return m_kind == other.m_kind
>+            && m_info == other.m_info;
>+    }
>+    
>+    bool operator!=(const PromotedLocationDescriptor& other) const
>+    {
>+        return !(*this == other);
>+    }
>+
>+    bool isHashTableDeletedValue() const
>+    {
>+        return m_kind == InvalidPromotedLocationKind && m_info;
>+    }
>+    
>+    void dump(PrintStream& out) const;
>+
>+private:
>+    PromotedLocationKind m_kind;
>+    unsigned m_info;
>+};
>+
>+class PromotedHeapLocation {
>+public:
>+    PromotedHeapLocation(
>+        PromotedLocationKind kind = InvalidPromotedLocationKind,
>+        Node* base = nullptr, unsigned info = 0)
>+        : m_base(base)
>+        , m_meta(kind, info)
>+    {
>+    }
>+    
>+    PromotedHeapLocation(
>+        PromotedLocationKind kind, Edge base, unsigned info = 0)
>+        : PromotedHeapLocation(kind, base.node(), info)
>+    {
>+    }
>+    
>+    PromotedHeapLocation(Node* base, PromotedLocationDescriptor meta)
>+        : m_base(base)
>+        , m_meta(meta)
>+    {
>+    }
>+    
>+    PromotedHeapLocation(WTF::HashTableDeletedValueType)
>+        : m_base(nullptr)
>+        , m_meta(InvalidPromotedLocationKind, 1)
>+    {
>+    }
>+    
>+    Node* createHint(Graph&, NodeOrigin, Node* value);
>+    
>+    bool operator!() const { return kind() == InvalidPromotedLocationKind; }
>+    
>+    PromotedLocationKind kind() const { return m_meta.kind(); }
>+    Node* base() const { return m_base; }
>+    unsigned info() const { return m_meta.info(); }
>+    PromotedLocationDescriptor descriptor() const { return m_meta; }
>+    
>+    unsigned hash() const
>+    {
>+        return m_meta.hash() + WTF::PtrHash<Node*>::hash(m_base);
>+    }
>+    
>+    bool operator==(const PromotedHeapLocation& other) const
>+    {
>+        return m_base == other.m_base
>+            && m_meta == other.m_meta;
>+    }
>+    
>+    bool isHashTableDeletedValue() const
>+    {
>+        return m_meta.isHashTableDeletedValue();
>+    }
>+    
>+    void dump(PrintStream& out) const;
>+    
>+private:
>+    Node* m_base;
>+    PromotedLocationDescriptor m_meta;
>+};
>+
>+struct PromotedHeapLocationHash {
>+    static unsigned hash(const PromotedHeapLocation& key) { return key.hash(); }
>+    static bool equal(const PromotedHeapLocation& a, const PromotedHeapLocation& b) { return a == b; }
>+    static const bool safeToCompareToEmptyOrDeleted = true;
>+};
>+
>+} } // namespace JSC::DFG
>+
>+namespace WTF {
>+
>+void printInternal(PrintStream&, JSC::DFG::PromotedLocationKind);
>+
>+template<typename T> struct DefaultHash;
>+template<> struct DefaultHash<JSC::DFG::PromotedHeapLocation> {
>+    typedef JSC::DFG::PromotedHeapLocationHash Hash;
>+};
>+
>+template<typename T> struct HashTraits;
>+template<> struct HashTraits<JSC::DFG::PromotedHeapLocation> : SimpleClassHashTraits<JSC::DFG::PromotedHeapLocation> {
>+    static const bool emptyValueIsZero = false;
>+};
>+
>+} // namespace WTF
>+
>+#endif // ENABLE(DFG_JIT)
>+
>+#endif // DFGPromotedHeapLocation_h
>+
>Index: Source/JavaScriptCore/dfg/DFGSSACalculator.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGSSACalculator.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGSSACalculator.cpp	(working copy)
>@@ -66,6 +66,17 @@ SSACalculator::~SSACalculator()
> {
> }
> 
>+void SSACalculator::reset()
>+{
>+    m_variables.clear();
>+    m_defs.clear();
>+    m_phis.clear();
>+    for (BlockIndex blockIndex = m_data.size(); blockIndex--;) {
>+        m_data[blockIndex].m_defs.clear();
>+        m_data[blockIndex].m_phis.clear();
>+    }
>+}
>+
> SSACalculator::Variable* SSACalculator::newVariable()
> {
>     return &m_variables.alloc(Variable(m_variables.size()));
>Index: Source/JavaScriptCore/dfg/DFGSSACalculator.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGSSACalculator.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGSSACalculator.h	(working copy)
>@@ -105,6 +105,8 @@ public:
>     SSACalculator(Graph&);
>     ~SSACalculator();
>     
>+    void reset();
>+    
>     class Variable {
>     public:
>         unsigned index() const { return m_index; }
>Index: Source/JavaScriptCore/dfg/DFGSafeToExecute.h
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGSafeToExecute.h	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGSafeToExecute.h	(working copy)
>@@ -270,6 +270,11 @@ bool safeToExecute(AbstractStateType& st
>     case GetGenericPropertyEnumerator:
>     case GetEnumeratorPname:
>     case ToIndexString:
>+    case PhantomNewObject:
>+    case PutByOffsetHint:
>+    case CheckStructureImmediate:
>+    case PutStructureHint:
>+    case MaterializeNewObject:
>         return true;
> 
>     case NativeCall:
>Index: Source/JavaScriptCore/dfg/DFGSpeculativeJIT32_64.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGSpeculativeJIT32_64.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGSpeculativeJIT32_64.cpp	(working copy)
>@@ -4912,6 +4912,11 @@ void SpeculativeJIT::compile(Node* node)
>     case NativeConstruct:
>     case CheckBadCell:
>     case BottomValue:
>+    case PhantomNewObject:
>+    case PutByOffsetHint:
>+    case CheckStructureImmediate:
>+    case PutStructureHint:
>+    case MaterializeNewObject:
>         RELEASE_ASSERT_NOT_REACHED();
>         break;
>     }
>Index: Source/JavaScriptCore/dfg/DFGSpeculativeJIT64.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGSpeculativeJIT64.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGSpeculativeJIT64.cpp	(working copy)
>@@ -4982,6 +4982,11 @@ void SpeculativeJIT::compile(Node* node)
>     case FiatInt52:
>     case CheckBadCell:
>     case BottomValue:
>+    case PhantomNewObject:
>+    case PutByOffsetHint:
>+    case CheckStructureImmediate:
>+    case PutStructureHint:
>+    case MaterializeNewObject:
>         DFG_CRASH(m_jit.graph(), node, "Unexpected node");
>         break;
>     }
>Index: Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp	(working copy)
>@@ -1415,7 +1415,7 @@ void SpeculativeJIT::compileCurrentBlock
>         else
>             m_canExit = mayExit(m_jit.graph(), m_currentNode);
>         
>-        bool shouldExecuteEffects = m_interpreter.startExecuting(m_currentNode);
>+        m_interpreter.startExecuting();
>         m_jit.setForNode(m_currentNode);
>         m_codeOriginForExitTarget = m_currentNode->origin.forExit;
>         m_codeOriginForExitProfile = m_currentNode->origin.semantic;
>@@ -1472,8 +1472,7 @@ void SpeculativeJIT::compileCurrentBlock
>         }
>         
>         // Make sure that the abstract state is rematerialized for the next node.
>-        if (shouldExecuteEffects)
>-            m_interpreter.executeEffects(m_indexInBlock);
>+        m_interpreter.executeEffects(m_indexInBlock);
>     }
>     
>     // Perform the most basic verification that children have been used correctly.
>Index: Source/JavaScriptCore/dfg/DFGStructureRegistrationPhase.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGStructureRegistrationPhase.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGStructureRegistrationPhase.cpp	(working copy)
>@@ -47,6 +47,7 @@ public:
>         // These are pretty dumb, but needed to placate subsequent assertions. We don't actually
>         // have to watch these because there is no way to transition away from it, but they are
>         // watchable and so we will assert if they aren't watched.
>+        registerStructure(m_graph.m_vm.structureStructure.get());
>         registerStructure(m_graph.m_vm.stringStructure.get());
>         registerStructure(m_graph.m_vm.getterSetterStructure.get());
>         
>Index: Source/JavaScriptCore/dfg/DFGValidate.cpp
>===================================================================
>--- Source/JavaScriptCore/dfg/DFGValidate.cpp	(revision 173938)
>+++ Source/JavaScriptCore/dfg/DFGValidate.cpp	(working copy)
>@@ -187,8 +187,6 @@ public:
>                 Node* node = block->node(i);
>                 if (m_graph.m_refCountState == ExactRefCount)
>                     V_EQUAL((node), m_myRefCounts.get(node), node->adjustedRefCount());
>-                else
>-                    V_EQUAL((node), node->refCount(), 1);
>             }
>             
>             for (size_t i = 0 ; i < block->size() - 1; ++i) {
>Index: Source/JavaScriptCore/ftl/FTLCapabilities.cpp
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLCapabilities.cpp	(revision 173938)
>+++ Source/JavaScriptCore/ftl/FTLCapabilities.cpp	(working copy)
>@@ -168,6 +168,11 @@ inline CapabilityLevel canCompile(Node* 
>     case GetEnumeratorPname:
>     case ToIndexString:
>     case BottomValue:
>+    case PhantomNewObject:
>+    case PutByOffsetHint:
>+    case CheckStructureImmediate:
>+    case PutStructureHint:
>+    case MaterializeNewObject:
>         // These are OK.
>         break;
>     case ProfiledCall:
>Index: Source/JavaScriptCore/ftl/FTLExitPropertyValue.cpp
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLExitPropertyValue.cpp	(revision 0)
>+++ Source/JavaScriptCore/ftl/FTLExitPropertyValue.cpp	(working copy)
>@@ -0,0 +1,41 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "FTLExitPropertyValue.h"
>+
>+#if ENABLE(FTL_JIT)
>+
>+namespace JSC { namespace FTL {
>+
>+void ExitPropertyValue::dump(PrintStream& out) const
>+{
>+    out.print(m_location, " => ", m_value);
>+}
>+
>+} } // namespace JSC::FTL
>+
>+#endif // ENABLE(FTL_JIT)
>+
>Index: Source/JavaScriptCore/ftl/FTLExitPropertyValue.h
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLExitPropertyValue.h	(revision 0)
>+++ Source/JavaScriptCore/ftl/FTLExitPropertyValue.h	(working copy)
>@@ -0,0 +1,66 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef FTLExitPropertyValue_h
>+#define FTLExitPropertyValue_h
>+
>+#if ENABLE(FTL_JIT)
>+
>+#include "DFGPromotedHeapLocation.h"
>+#include "FTLExitValue.h"
>+
>+namespace JSC { namespace FTL {
>+
>+class ExitPropertyValue {
>+public:
>+    ExitPropertyValue()
>+    {
>+    }
>+    
>+    ExitPropertyValue(DFG::PromotedLocationDescriptor location, const ExitValue& value)
>+        : m_location(location)
>+        , m_value(value)
>+    {
>+        ASSERT(!!location == !!value);
>+    }
>+    
>+    bool operator!() const { return !m_location; }
>+    
>+    DFG::PromotedLocationDescriptor location() const { return m_location; }
>+    const ExitValue& value() const { return m_value; }
>+    
>+    void dump(PrintStream& out) const;
>+
>+private:
>+    DFG::PromotedLocationDescriptor m_location;
>+    ExitValue m_value;
>+};
>+
>+} } // namespace JSC::FTL
>+
>+#endif // ENABLE(FTL_JIT)
>+
>+#endif // FTLExitPropertyValue_h
>+
>Index: Source/JavaScriptCore/ftl/FTLExitTimeObjectMaterialization.cpp
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLExitTimeObjectMaterialization.cpp	(revision 0)
>+++ Source/JavaScriptCore/ftl/FTLExitTimeObjectMaterialization.cpp	(working copy)
>@@ -0,0 +1,69 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "FTLExitTimeObjectMaterialization.h"
>+
>+#if ENABLE(FTL_JIT)
>+
>+#include "DFGGraph.h"
>+
>+namespace JSC { namespace FTL {
>+
>+using namespace JSC::DFG;
>+
>+ExitTimeObjectMaterialization::ExitTimeObjectMaterialization(NodeType type)
>+    : m_type(type)
>+{
>+}
>+
>+ExitTimeObjectMaterialization::~ExitTimeObjectMaterialization()
>+{
>+}
>+
>+void ExitTimeObjectMaterialization::add(
>+    PromotedLocationDescriptor location, const ExitValue& value)
>+{
>+    m_properties.append(ExitPropertyValue(location, value));
>+}
>+
>+ExitValue ExitTimeObjectMaterialization::get(PromotedLocationDescriptor location) const
>+{
>+    for (ExitPropertyValue value : m_properties) {
>+        if (value.location() == location)
>+            return value.value();
>+    }
>+    return ExitValue();
>+}
>+
>+void ExitTimeObjectMaterialization::dump(PrintStream& out) const
>+{
>+    out.print(RawPointer(this), ":", Graph::opName(m_type), "(", listDump(m_properties), ")");
>+}
>+
>+} } // namespace JSC::FTL
>+
>+#endif // ENABLE(FTL_JIT)
>+
>Index: Source/JavaScriptCore/ftl/FTLExitTimeObjectMaterialization.h
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLExitTimeObjectMaterialization.h	(revision 0)
>+++ Source/JavaScriptCore/ftl/FTLExitTimeObjectMaterialization.h	(working copy)
>@@ -0,0 +1,63 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef FTLExitTimeObjectMaterialization_h
>+#define FTLExitTimeObjectMaterialization_h
>+
>+#if ENABLE(FTL_JIT)
>+
>+#include "DFGNodeType.h"
>+#include "FTLExitPropertyValue.h"
>+#include "FTLExitValue.h"
>+#include <wtf/Noncopyable.h>
>+
>+namespace JSC { namespace FTL {
>+
>+class ExitTimeObjectMaterialization {
>+    WTF_MAKE_NONCOPYABLE(ExitTimeObjectMaterialization)
>+public:
>+    ExitTimeObjectMaterialization(DFG::NodeType);
>+    ~ExitTimeObjectMaterialization();
>+    
>+    void add(DFG::PromotedLocationDescriptor, const ExitValue&);
>+    
>+    DFG::NodeType type() const { return m_type; }
>+    
>+    ExitValue get(DFG::PromotedLocationDescriptor) const;
>+    const Vector<ExitPropertyValue>& properties() const { return m_properties; }
>+    
>+    void dump(PrintStream& out) const;
>+    
>+private:
>+    DFG::NodeType m_type;
>+    Vector<ExitPropertyValue> m_properties;
>+};
>+
>+} } // namespace JSC::FTL
>+
>+#endif // ENABLE(FTL_JIT)
>+
>+#endif // FTLExitTimeObjectMaterialization_h
>+
>Index: Source/JavaScriptCore/ftl/FTLExitValue.cpp
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLExitValue.cpp	(revision 173938)
>+++ Source/JavaScriptCore/ftl/FTLExitValue.cpp	(working copy)
>@@ -28,10 +28,19 @@
> 
> #if ENABLE(FTL_JIT)
> 
>+#include "FTLExitTimeObjectMaterialization.h"
> #include "JSCInlines.h"
> 
> namespace JSC { namespace FTL {
> 
>+ExitValue ExitValue::materializeNewObject(ExitTimeObjectMaterialization* data)
>+{
>+    ExitValue result;
>+    result.m_kind = ExitValueMaterializeNewObject;
>+    result.u.newObjectMaterializationData = data;
>+    return result;
>+}
>+
> void ExitValue::dumpInContext(PrintStream& out, DumpContext* context) const
> {
>     switch (kind()) {
>@@ -65,6 +74,9 @@ void ExitValue::dumpInContext(PrintStrea
>     case ExitValueRecovery:
>         out.print("Recovery(", recoveryOpcode(), ", arg", leftRecoveryArgument(), ", arg", rightRecoveryArgument(), ", ", recoveryFormat(), ")");
>         return;
>+    case ExitValueMaterializeNewObject:
>+        out.print("Materialize(", pointerDump(objectMaterialization()), ")");
>+        return;
>     }
>     
>     RELEASE_ASSERT_NOT_REACHED();
>Index: Source/JavaScriptCore/ftl/FTLExitValue.h
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLExitValue.h	(revision 173938)
>+++ Source/JavaScriptCore/ftl/FTLExitValue.h	(working copy)
>@@ -52,9 +52,12 @@ enum ExitValueKind {
>     ExitValueInJSStackAsInt52,
>     ExitValueInJSStackAsDouble,
>     ExitValueArgumentsObjectThatWasNotCreated,
>-    ExitValueRecovery
>+    ExitValueRecovery,
>+    ExitValueMaterializeNewObject
> };
> 
>+class ExitTimeObjectMaterialization;
>+
> class ExitValue {
> public:
>     ExitValue()
>@@ -137,6 +140,8 @@ public:
>         return result;
>     }
>     
>+    static ExitValue materializeNewObject(ExitTimeObjectMaterialization*);
>+    
>     ExitValueKind kind() const { return m_kind; }
>     
>     bool isDead() const { return kind() == ExitValueDead; }
>@@ -156,6 +161,7 @@ public:
>     bool isArgument() const { return kind() == ExitValueArgument; }
>     bool isArgumentsObjectThatWasNotCreated() const { return kind() == ExitValueArgumentsObjectThatWasNotCreated; }
>     bool isRecovery() const { return kind() == ExitValueRecovery; }
>+    bool isObjectMaterialization() const { return kind() == ExitValueMaterializeNewObject; }
>     
>     ExitArgument exitArgument() const
>     {
>@@ -199,7 +205,13 @@ public:
>         return VirtualRegister(u.virtualRegister);
>     }
>     
>-    ExitValue withVirtualRegister(VirtualRegister virtualRegister)
>+    ExitTimeObjectMaterialization* objectMaterialization() const
>+    {
>+        ASSERT(isObjectMaterialization());
>+        return u.newObjectMaterializationData;
>+    }
>+
>+    ExitValue withVirtualRegister(VirtualRegister virtualRegister) const
>     {
>         ASSERT(isInJSStackSomehow());
>         ExitValue result;
>@@ -207,7 +219,7 @@ public:
>         result.u.virtualRegister = virtualRegister.offset();
>         return result;
>     }
>-
>+    
>     // If it's in the JSStack somehow, this will tell you what format it's in, in a manner
>     // that is compatible with exitArgument().format(). If it's a constant or it's dead, it
>     // will claim to be a JSValue. If it's an argument then it will tell you the argument's
>@@ -223,6 +235,7 @@ public:
>         case ExitValueConstant:
>         case ExitValueInJSStack:
>         case ExitValueArgumentsObjectThatWasNotCreated:
>+        case ExitValueMaterializeNewObject:
>             return ValueFormatJSValue;
>             
>         case ExitValueArgument:
>@@ -260,6 +273,7 @@ private:
>             uint16_t opcode;
>             uint16_t format;
>         } recovery;
>+        ExitTimeObjectMaterialization* newObjectMaterializationData;
>     } u;
> };
> 
>Index: Source/JavaScriptCore/ftl/FTLLowerDFGToLLVM.cpp
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLLowerDFGToLLVM.cpp	(revision 173938)
>+++ Source/JavaScriptCore/ftl/FTLLowerDFGToLLVM.cpp	(working copy)
>@@ -38,6 +38,7 @@
> #include "FTLFormattedValue.h"
> #include "FTLInlineCacheSize.h"
> #include "FTLLoweredNodeValue.h"
>+#include "FTLOperations.h"
> #include "FTLOutput.h"
> #include "FTLThunks.h"
> #include "FTLWeightedTarget.h"
>@@ -341,7 +342,7 @@ private:
>         
>         m_availableRecoveries.resize(0);
>         
>-        bool shouldExecuteEffects = m_interpreter.startExecuting(m_node);
>+        m_interpreter.startExecuting();
>         
>         switch (m_node->op()) {
>         case Upsilon:
>@@ -725,6 +726,12 @@ private:
>         case ToIndexString:
>             compileToIndexString();
>             break;
>+        case CheckStructureImmediate:
>+            compileCheckStructureImmediate();
>+            break;
>+        case MaterializeNewObject:
>+            compileMaterializeNewObject();
>+            break;
> 
>         case PhantomLocal:
>         case SetArgument:
>@@ -735,6 +742,10 @@ private:
>         case AllocationProfileWatchpoint:
>         case MovHint:
>         case ZombieHint:
>+        case PhantomNewObject:
>+        case PutByOffsetHint:
>+        case PutStructureHint:
>+        case BottomValue:
>             break;
>         default:
>             DFG_CRASH(m_graph, m_node, "Unrecognized node in FTL backend");
>@@ -742,9 +753,7 @@ private:
>         }
>         
>         m_availabilityCalculator.executeNode(m_node);
>-        
>-        if (shouldExecuteEffects)
>-            m_interpreter.executeEffects(nodeIndex);
>+        m_interpreter.executeEffects(nodeIndex);
>         
>         return true;
>     }
>@@ -1704,30 +1713,7 @@ private:
>         
>         LValue structureID = m_out.load32(cell, m_heaps.JSCell_structureID);
>         
>-        if (m_node->structureSet().size() == 1) {
>-            speculate(
>-                exitKind, jsValueValue(cell), 0,
>-                m_out.notEqual(structureID, weakStructure(m_node->structureSet()[0])));
>-            return;
>-        }
>-        
>-        LBasicBlock continuation = FTL_NEW_BLOCK(m_out, ("CheckStructure continuation"));
>-        
>-        LBasicBlock lastNext = m_out.insertNewBlocksBefore(continuation);
>-        for (unsigned i = 0; i < m_node->structureSet().size() - 1; ++i) {
>-            LBasicBlock nextStructure = FTL_NEW_BLOCK(m_out, ("CheckStructure nextStructure"));
>-            m_out.branch(
>-                m_out.equal(structureID, weakStructure(m_node->structureSet()[i])),
>-                unsure(continuation), unsure(nextStructure));
>-            m_out.appendTo(nextStructure);
>-        }
>-        
>-        speculate(
>-            exitKind, jsValueValue(cell), 0,
>-            m_out.notEqual(structureID, weakStructure(m_node->structureSet().last())));
>-        
>-        m_out.jump(continuation);
>-        m_out.appendTo(continuation, lastNext);
>+        checkStructure(structureID, jsValueValue(cell), exitKind, m_node->structureSet());
>     }
>     
>     void compileCheckCell()
>@@ -1762,7 +1748,7 @@ private:
>         LValue structureID = m_out.load32(cell, m_heaps.JSCell_structureID);
>         
>         m_out.branch(
>-            m_out.notEqual(structureID, weakStructure(m_node->structure())),
>+            m_out.notEqual(structureID, weakStructureID(m_node->structure())),
>             rarely(unexpectedStructure), usually(continuation));
>         
>         LBasicBlock lastNext = m_out.appendTo(unexpectedStructure, continuation);
>@@ -1806,7 +1792,7 @@ private:
>         structureID = m_out.load32(cell, m_heaps.JSCell_structureID);
>         speculate(
>             BadIndexingType, jsValueValue(cell), 0,
>-            m_out.notEqual(structureID, weakStructure(m_node->structure())));
>+            m_out.notEqual(structureID, weakStructureID(m_node->structure())));
>         m_out.jump(continuation);
>         
>         m_out.appendTo(continuation, lastNext);
>@@ -1824,7 +1810,7 @@ private:
> 
>         LValue cell = lowCell(m_node->child1()); 
>         m_out.store32(
>-            weakStructure(newStructure),
>+            weakStructureID(newStructure),
>             cell, m_heaps.JSCell_structureID);
>     }
>     
>@@ -2649,28 +2635,7 @@ private:
>     
>     void compileNewObject()
>     {
>-        Structure* structure = m_node->structure();
>-        size_t allocationSize = JSFinalObject::allocationSize(structure->inlineCapacity());
>-        MarkedAllocator* allocator = &vm().heap.allocatorForObjectWithoutDestructor(allocationSize);
>-        
>-        LBasicBlock slowPath = FTL_NEW_BLOCK(m_out, ("NewObject slow path"));
>-        LBasicBlock continuation = FTL_NEW_BLOCK(m_out, ("NewObject continuation"));
>-        
>-        LBasicBlock lastNext = m_out.insertNewBlocksBefore(slowPath);
>-        
>-        ValueFromBlock fastResult = m_out.anchor(allocateObject(
>-            m_out.constIntPtr(allocator), structure, m_out.intPtrZero, slowPath));
>-        
>-        m_out.jump(continuation);
>-        
>-        m_out.appendTo(slowPath, continuation);
>-        
>-        ValueFromBlock slowResult = m_out.anchor(vmCall(
>-            m_out.operation(operationNewObject), m_callFrame, m_out.constIntPtr(structure)));
>-        m_out.jump(continuation);
>-        
>-        m_out.appendTo(continuation, lastNext);
>-        setJSValue(m_out.phi(m_out.intPtr, fastResult, slowResult));
>+        setJSValue(allocateObject(m_node->structure()));
>     }
>     
>     void compileNewArray()
>@@ -3290,7 +3255,7 @@ private:
>             GetByIdVariant variant = data.variants[i];
>             for (unsigned j = variant.structureSet().size(); j--;) {
>                 cases.append(SwitchCase(
>-                    weakStructure(variant.structureSet()[j]), blocks[i], Weight(1)));
>+                    weakStructureID(variant.structureSet()[j]), blocks[i], Weight(1)));
>             }
>         }
>         m_out.switchInstruction(
>@@ -3361,7 +3326,7 @@ private:
>             PutByIdVariant variant = data.variants[i];
>             for (unsigned j = variant.oldStructure().size(); j--;) {
>                 cases.append(
>-                    SwitchCase(weakStructure(variant.oldStructure()[j]), blocks[i], Weight(1)));
>+                    SwitchCase(weakStructureID(variant.oldStructure()[j]), blocks[i], Weight(1)));
>             }
>         }
>         m_out.switchInstruction(
>@@ -3370,7 +3335,7 @@ private:
>         LBasicBlock lastNext = m_out.m_nextBlock;
>         
>         for (unsigned i = data.variants.size(); i--;) {
>-            m_out.appendTo(blocks[i], i  + 1 < data.variants.size() ? blocks[i + 1] : exit);
>+            m_out.appendTo(blocks[i], i + 1 < data.variants.size() ? blocks[i + 1] : exit);
>             
>             PutByIdVariant variant = data.variants[i];
>             
>@@ -3393,7 +3358,7 @@ private:
>                 ASSERT(variant.oldStructureForTransition()->typeInfo().inlineTypeFlags() == variant.newStructure()->typeInfo().inlineTypeFlags());
>                 ASSERT(variant.oldStructureForTransition()->typeInfo().type() == variant.newStructure()->typeInfo().type());
>                 m_out.store32(
>-                    weakStructure(variant.newStructure()), base, m_heaps.JSCell_structureID);
>+                    weakStructureID(variant.newStructure()), base, m_heaps.JSCell_structureID);
>             }
>             
>             storeProperty(value, storage, data.identifierNumber, variant.offset());
>@@ -3953,12 +3918,13 @@ private:
>     void compileInvalidationPoint()
>     {
>         if (verboseCompilationEnabled())
>-            dataLog("    Invalidation point with availability: ", availability(), "\n");
>+            dataLog("    Invalidation point with availability: ", availabilityMap(), "\n");
>         
>         m_ftlState.jitCode->osrExit.append(OSRExit(
>             UncountableInvalidation, InvalidValueFormat, MethodOfGettingAValueProfile(),
>             m_codeOriginForExitTarget, m_codeOriginForExitProfile,
>-            availability().numberOfArguments(), availability().numberOfLocals()));
>+            availabilityMap().m_locals.numberOfArguments(),
>+            availabilityMap().m_locals.numberOfLocals()));
>         m_ftlState.finalizer->osrExit.append(OSRExitCompilationInfo());
>         
>         OSRExit& exit = m_ftlState.jitCode->osrExit.last();
>@@ -4360,6 +4326,120 @@ private:
>         LValue index = lowInt32(m_node->child1());
>         setJSValue(vmCall(m_out.operation(operationToIndexString), m_callFrame, index));
>     }
>+    
>+    void compileCheckStructureImmediate()
>+    {
>+        LValue structureID = lowCell(m_node->child1());
>+        checkStructure(structureID, noValue(), BadCache, m_node->structureSet());
>+    }
>+    
>+    void compileMaterializeNewObject()
>+    {
>+        ObjectMaterializationData& data = m_node->objectMaterializationData();
>+        
>+        // Lower the values first, to avoid creating values inside a control flow diamond.
>+        
>+        Vector<LValue, 8> values;
>+        for (unsigned i = 0; i < data.m_properties.size(); ++i)
>+            values.append(lowJSValue(m_graph.varArgChild(m_node, 1 + i)));
>+        
>+        StructureSet set;
>+        m_interpreter.phiChildren()->forAllTransitiveIncomingValues(
>+            m_graph.varArgChild(m_node, 0).node(),
>+            [&] (Node* incoming) {
>+                set.add(incoming->castConstant<Structure*>());
>+            });
>+        
>+        Vector<LBasicBlock, 1> blocks(set.size());
>+        for (unsigned i = set.size(); i--;)
>+            blocks[i] = FTL_NEW_BLOCK(m_out, ("MaterializeNewObject case ", i));
>+        LBasicBlock dummyDefault = FTL_NEW_BLOCK(m_out, ("MaterializeNewObject default case"));
>+        LBasicBlock outerContinuation = FTL_NEW_BLOCK(m_out, ("MaterializeNewObject continuation"));
>+        
>+        Vector<SwitchCase, 1> cases(set.size());
>+        for (unsigned i = set.size(); i--;)
>+            cases[i] = SwitchCase(weakStructure(set[i]), blocks[i], Weight(1));
>+        m_out.switchInstruction(
>+            lowCell(m_graph.varArgChild(m_node, 0)), cases, dummyDefault, Weight(0));
>+        
>+        LBasicBlock outerLastNext = m_out.m_nextBlock;
>+        
>+        Vector<ValueFromBlock, 1> results;
>+        
>+        for (unsigned i = set.size(); i--;) {
>+            m_out.appendTo(blocks[i], i + 1 < set.size() ? blocks[i + 1] : dummyDefault);
>+            
>+            Structure* structure = set[i];
>+            
>+            LValue object;
>+            LValue butterfly;
>+            
>+            if (structure->outOfLineCapacity()) {
>+                size_t allocationSize = JSFinalObject::allocationSize(structure->inlineCapacity());
>+                MarkedAllocator* allocator = &vm().heap.allocatorForObjectWithoutDestructor(allocationSize);
>+                
>+                LBasicBlock slowPath = FTL_NEW_BLOCK(m_out, ("MaterializeNewObject complex object allocation slow path"));
>+                LBasicBlock continuation = FTL_NEW_BLOCK(m_out, ("MaterializeNewObject complex object allocation continuation"));
>+                
>+                LBasicBlock lastNext = m_out.insertNewBlocksBefore(slowPath);
>+                
>+                LValue endOfStorage = allocateBasicStorageAndGetEnd(
>+                    m_out.constIntPtr(structure->outOfLineCapacity() * sizeof(JSValue)),
>+                    slowPath);
>+                
>+                LValue fastButterflyValue = m_out.add(
>+                    m_out.constIntPtr(sizeof(IndexingHeader)), endOfStorage);
>+                
>+                LValue fastObjectValue = allocateObject(
>+                    m_out.constIntPtr(allocator), structure, fastButterflyValue, slowPath);
>+
>+                ValueFromBlock fastObject = m_out.anchor(fastObjectValue);
>+                ValueFromBlock fastButterfly = m_out.anchor(fastButterflyValue);
>+                m_out.jump(continuation);
>+                
>+                m_out.appendTo(slowPath, continuation);
>+                
>+                ValueFromBlock slowObject = m_out.anchor(vmCall(
>+                    m_out.operation(operationNewObjectWithButterfly),
>+                    m_callFrame, m_out.constIntPtr(structure)));
>+                ValueFromBlock slowButterfly = m_out.anchor(
>+                    m_out.loadPtr(slowObject.value(), m_heaps.JSObject_butterfly));
>+                
>+                m_out.jump(continuation);
>+                
>+                m_out.appendTo(continuation, lastNext);
>+                
>+                object = m_out.phi(m_out.intPtr, fastObject, slowObject);
>+                butterfly = m_out.phi(m_out.intPtr, fastButterfly, slowButterfly);
>+            } else {
>+                // In the easy case where we can do a one-shot allocation, we simply allocate the
>+                // object to directly have the desired structure.
>+                object = allocateObject(structure);
>+                butterfly = nullptr; // Don't have one, don't need one.
>+            }
>+            
>+            for (PropertyMapEntry entry : structure->getPropertiesConcurrently()) {
>+                for (unsigned i = data.m_properties.size(); i--;) {
>+                    PhantomPropertyValue value = data.m_properties[i];
>+                    if (m_graph.identifiers()[value.m_identifierNumber] != entry.key)
>+                        continue;
>+                    
>+                    LValue base = isInlineOffset(entry.offset) ? object : butterfly;
>+                    storeProperty(values[i], base, value.m_identifierNumber, entry.offset);
>+                    break;
>+                }
>+            }
>+            
>+            results.append(m_out.anchor(object));
>+            m_out.jump(outerContinuation);
>+        }
>+        
>+        m_out.appendTo(dummyDefault, outerContinuation);
>+        m_out.unreachable();
>+        
>+        m_out.appendTo(outerContinuation, outerLastNext);
>+        setJSValue(m_out.phi(m_out.intPtr, results));
>+    }
> 
> #if ENABLE(FTL_NATIVE_CALL_INLINING)
>     LValue getFunctionBySymbol(const CString symbol)
>@@ -4525,6 +4605,36 @@ private:
>         return m_out.booleanFalse;
>     }
>     
>+    void checkStructure(
>+        LValue structureID, const FormattedValue& formattedValue, ExitKind exitKind,
>+        const StructureSet& set)
>+    {
>+        if (set.size() == 1) {
>+            speculate(
>+                exitKind, formattedValue, 0,
>+                m_out.notEqual(structureID, weakStructureID(set[0])));
>+            return;
>+        }
>+        
>+        LBasicBlock continuation = FTL_NEW_BLOCK(m_out, ("checkStructure continuation"));
>+        
>+        LBasicBlock lastNext = m_out.insertNewBlocksBefore(continuation);
>+        for (unsigned i = 0; i < set.size() - 1; ++i) {
>+            LBasicBlock nextStructure = FTL_NEW_BLOCK(m_out, ("checkStructure nextStructure"));
>+            m_out.branch(
>+                m_out.equal(structureID, weakStructureID(set[i])),
>+                unsure(continuation), unsure(nextStructure));
>+            m_out.appendTo(nextStructure);
>+        }
>+        
>+        speculate(
>+            exitKind, formattedValue, 0,
>+            m_out.notEqual(structureID, weakStructureID(set.last())));
>+        
>+        m_out.jump(continuation);
>+        m_out.appendTo(continuation, lastNext);
>+    }
>+    
>     LValue numberOrNotCellToInt32(Edge edge, LValue value)
>     {
>         LBasicBlock intCase = FTL_NEW_BLOCK(m_out, ("ValueToInt32 int case"));
>@@ -4831,7 +4941,7 @@ private:
>         setBoolean(m_out.phi(m_out.boolean, fastResult, slowResult));
>     }
> 
>-    LValue allocateCell(LValue allocator, Structure* structure, LBasicBlock slowPath)
>+    LValue allocateCell(LValue allocator, LBasicBlock slowPath)
>     {
>         LBasicBlock success = FTL_NEW_BLOCK(m_out, ("object allocation success"));
>         
>@@ -4846,12 +4956,21 @@ private:
>             m_out.loadPtr(result, m_heaps.JSCell_freeListNext),
>             allocator, m_heaps.MarkedAllocator_freeListHead);
>         
>-        m_out.store32(m_out.constInt32(structure->id()), result, m_heaps.JSCell_structureID);
>-        
>+        return result;
>+    }
>+    
>+    void storeStructure(LValue object, Structure* structure)
>+    {
>+        m_out.store32(m_out.constInt32(structure->id()), object, m_heaps.JSCell_structureID);
>         m_out.store32(
>             m_out.constInt32(structure->objectInitializationBlob()),
>-            result, m_heaps.JSCell_usefulBytes);
>-        
>+            object, m_heaps.JSCell_usefulBytes);
>+    }
>+
>+    LValue allocateCell(LValue allocator, Structure* structure, LBasicBlock slowPath)
>+    {
>+        LValue result = allocateCell(allocator, slowPath);
>+        storeStructure(result, structure);
>         return result;
>     }
> 
>@@ -4898,6 +5017,31 @@ private:
>             m_out.loadPtr(m_out.absolute(&allocator.m_currentPayloadEnd)), newRemaining);
>     }
>     
>+    LValue allocateObject(Structure* structure)
>+    {
>+        size_t allocationSize = JSFinalObject::allocationSize(structure->inlineCapacity());
>+        MarkedAllocator* allocator = &vm().heap.allocatorForObjectWithoutDestructor(allocationSize);
>+        
>+        LBasicBlock slowPath = FTL_NEW_BLOCK(m_out, ("allocateObject slow path"));
>+        LBasicBlock continuation = FTL_NEW_BLOCK(m_out, ("allocateObject continuation"));
>+        
>+        LBasicBlock lastNext = m_out.insertNewBlocksBefore(slowPath);
>+        
>+        ValueFromBlock fastResult = m_out.anchor(allocateObject(
>+            m_out.constIntPtr(allocator), structure, m_out.intPtrZero, slowPath));
>+        
>+        m_out.jump(continuation);
>+        
>+        m_out.appendTo(slowPath, continuation);
>+        
>+        ValueFromBlock slowResult = m_out.anchor(vmCall(
>+            m_out.operation(operationNewObject), m_callFrame, m_out.constIntPtr(structure)));
>+        m_out.jump(continuation);
>+        
>+        m_out.appendTo(continuation, lastNext);
>+        return m_out.phi(m_out.intPtr, fastResult, slowResult);
>+    }
>+    
>     struct ArrayValues {
>         ArrayValues()
>             : array(0)
>@@ -6107,7 +6251,7 @@ private:
>         
>         speculate(
>             NotStringObject, noValue(), 0,
>-            m_out.notEqual(structureID, weakStructure(stringObjectStructure)));
>+            m_out.notEqual(structureID, weakStructureID(stringObjectStructure)));
>     }
>     
>     void speculateNonNullObject(Edge edge, LValue cell)
>@@ -6334,7 +6478,7 @@ private:
>         ExitKind kind, FormattedValue lowValue, Node* highValue, LValue failCondition)
>     {
>         if (verboseCompilationEnabled()) {
>-            dataLog("    OSR exit #", m_ftlState.jitCode->osrExit.size(), " with availability: ", availability(), "\n");
>+            dataLog("    OSR exit #", m_ftlState.jitCode->osrExit.size(), " with availability: ", availabilityMap(), "\n");
>             if (!m_availableRecoveries.isEmpty())
>                 dataLog("        Available recoveries: ", listDump(m_availableRecoveries), "\n");
>         }
>@@ -6344,7 +6488,8 @@ private:
>         m_ftlState.jitCode->osrExit.append(OSRExit(
>             kind, lowValue.format(), m_graph.methodOfGettingAValueProfileFor(highValue),
>             m_codeOriginForExitTarget, m_codeOriginForExitProfile,
>-            availability().numberOfArguments(), availability().numberOfLocals()));
>+            availabilityMap().m_locals.numberOfArguments(),
>+            availabilityMap().m_locals.numberOfLocals()));
>         m_ftlState.finalizer->osrExit.append(OSRExitCompilationInfo());
>         
>         OSRExit& exit = m_ftlState.jitCode->osrExit.last();
>@@ -6384,56 +6529,52 @@ private:
>         if (!!lowValue)
>             arguments.append(lowValue.value());
>         
>+        AvailabilityMap availabilityMap = this->availabilityMap();
>+        
>         for (unsigned i = 0; i < exit.m_values.size(); ++i) {
>             int operand = exit.m_values.operandForIndex(i);
>             bool isLive = m_graph.isLiveInBytecode(VirtualRegister(operand), codeOrigin);
>-            if (!isLive) {
>-                exit.m_values[i] = ExitValue::dead();
>-                continue;
>-            }
>-            
>-            Availability availability = this->availability()[i];
>-            FlushedAt flush = availability.flushedAt();
>-            switch (flush.format()) {
>-            case DeadFlush:
>-            case ConflictingFlush:
>-                if (availability.hasNode()) {
>-                    exit.m_values[i] = exitValueForNode(arguments, availability.node());
>-                    break;
>-                }
>-                
>-                if (Options::validateFTLOSRExitLiveness())
>-                    DFG_CRASH(m_graph, m_node, toCString("Expected r", operand, " to be available but it wasn't.").data());
>-                
>-                // This means that the DFG's DCE proved that the value is dead in bytecode
>-                // even though the bytecode liveness analysis thinks it's live. This is
>-                // acceptable since the DFG's DCE is by design more aggressive while still
>-                // being sound.
>-                exit.m_values[i] = ExitValue::dead();
>-                break;
>-
>-            case FlushedJSValue:
>-            case FlushedCell:
>-            case FlushedBoolean:
>-                exit.m_values[i] = ExitValue::inJSStack(flush.virtualRegister());
>-                break;
>-                
>-            case FlushedInt32:
>-                exit.m_values[i] = ExitValue::inJSStackAsInt32(flush.virtualRegister());
>-                break;
>-                
>-            case FlushedInt52:
>-                exit.m_values[i] = ExitValue::inJSStackAsInt52(flush.virtualRegister());
>-                break;
>+            if (!isLive)
>+                availabilityMap.m_locals[i] = Availability();
>+        }
>+        
>+        availabilityMap.prune();
>+        
>+        HashMap<Node*, ExitTimeObjectMaterialization*> map;
>+        availabilityMap.forEachAvailability(
>+            [&] (Availability availability) {
>+                if (!availability.shouldUseNode())
>+                    return;
>                 
>-            case FlushedDouble:
>-                exit.m_values[i] = ExitValue::inJSStackAsDouble(flush.virtualRegister());
>-                break;
>+                Node* node = availability.node();
>+                if (!node->isPhantomObjectAllocation())
>+                    return;
>                 
>-            case FlushedArguments:
>-                exit.m_values[i] = ExitValue::argumentsObjectThatWasNotCreated();
>-                break;
>+                auto result = map.add(node, nullptr);
>+                if (result.isNewEntry)
>+                    result.iterator->value = exit.m_materializations.add(node->op());
>+            });
>+        
>+        for (unsigned i = 0; i < exit.m_values.size(); ++i) {
>+            int operand = exit.m_values.operandForIndex(i);
>+            
>+            Availability availability = availabilityMap.m_locals[i];
>+            
>+            if (Options::validateFTLOSRExitLiveness()) {
>+                DFG_ASSERT(
>+                    m_graph, m_node,
>+                    !(availability.isDead() && m_graph.isLiveInBytecode(VirtualRegister(operand), codeOrigin)));
>             }
>+            
>+            exit.m_values[i] = exitValueForAvailability(arguments, map, availability);
>+        }
>+        
>+        for (auto heapPair : availabilityMap.m_heap) {
>+            Node* node = heapPair.key.base();
>+            ExitTimeObjectMaterialization* materialization = map.get(node);
>+            materialization->add(
>+                heapPair.key.descriptor(),
>+                exitValueForAvailability(arguments, map, heapPair.value));
>         }
>         
>         if (verboseCompilationEnabled())
>@@ -6449,13 +6590,57 @@ private:
>         m_out.call(m_out.stackmapIntrinsic(), arguments);
>     }
>     
>-    ExitValue exitValueForNode(ExitArgumentList& arguments, Node* node)
>+    ExitValue exitValueForAvailability(
>+        ExitArgumentList& arguments, const HashMap<Node*, ExitTimeObjectMaterialization*>& map,
>+        Availability availability)
>+    {
>+        FlushedAt flush = availability.flushedAt();
>+        switch (flush.format()) {
>+        case DeadFlush:
>+        case ConflictingFlush:
>+            if (availability.hasNode())
>+                return exitValueForNode(arguments, map, availability.node());
>+            
>+            // This means that the value is dead. It could be dead in bytecode or it could have
>+            // been killed by our DCE, which can sometimes kill things even if they were live in
>+            // bytecode.
>+            return ExitValue::dead();
>+
>+        case FlushedJSValue:
>+        case FlushedCell:
>+        case FlushedBoolean:
>+            return ExitValue::inJSStack(flush.virtualRegister());
>+                
>+        case FlushedInt32:
>+            return ExitValue::inJSStackAsInt32(flush.virtualRegister());
>+                
>+        case FlushedInt52:
>+            return ExitValue::inJSStackAsInt52(flush.virtualRegister());
>+                
>+        case FlushedDouble:
>+            return ExitValue::inJSStackAsDouble(flush.virtualRegister());
>+                
>+        case FlushedArguments:
>+            return ExitValue::argumentsObjectThatWasNotCreated();
>+        }
>+        
>+        DFG_CRASH(m_graph, m_node, "Invalid flush format");
>+    }
>+    
>+    ExitValue exitValueForNode(
>+        ExitArgumentList& arguments, const HashMap<Node*, ExitTimeObjectMaterialization*>& map,
>+        Node* node)
>     {
>         ASSERT(node->shouldGenerate());
>         ASSERT(node->hasResult());
> 
>         if (node) {
>             switch (node->op()) {
>+            case BottomValue:
>+                // This might arise in object materializations. I actually doubt that it would,
>+                // but it seems worthwhile to be conservative.
>+                return ExitValue::dead();
>+                
>             case JSConstant:
>             case Int52Constant:
>             case DoubleConstant:
>@@ -6464,6 +6649,9 @@ private:
>             case PhantomArguments:
>                 return ExitValue::argumentsObjectThatWasNotCreated();
>                 
>+            case PhantomNewObject:
>+                return ExitValue::materializeNewObject(map.get(node));
>+                
>             default:
>                 break;
>             }
>@@ -6647,12 +6835,17 @@ private:
>         return m_out.constIntPtr(pointer);
>     }
> 
>-    LValue weakStructure(Structure* structure)
>+    LValue weakStructureID(Structure* structure)
>     {
>         addWeakReference(structure);
>         return m_out.constInt32(structure->id());
>     }
>     
>+    LValue weakStructure(Structure* structure)
>+    {
>+        return weakPointer(structure);
>+    }
>+    
>     TypedPointer addressFor(LValue base, int operand, ptrdiff_t offset = 0)
>     {
>         return m_out.address(base, m_heaps.variables[operand], offset);
>@@ -6711,7 +6904,7 @@ private:
>         m_out.unreachable();
>     }
>     
>-    Operands<Availability>& availability() { return m_availabilityCalculator.m_availability; }
>+    AvailabilityMap& availabilityMap() { return m_availabilityCalculator.m_availability; }
>     
>     VM& vm() { return m_graph.m_vm; }
>     CodeBlock* codeBlock() { return m_graph.m_codeBlock; }
>Index: Source/JavaScriptCore/ftl/FTLOSRExit.h
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLOSRExit.h	(revision 173938)
>+++ Source/JavaScriptCore/ftl/FTLOSRExit.h	(working copy)
>@@ -1,5 +1,5 @@
> /*
>- * Copyright (C) 2013 Apple Inc. All rights reserved.
>+ * Copyright (C) 2013, 2014 Apple Inc. All rights reserved.
>  *
>  * Redistribution and use in source and binary forms, with or without
>  * modification, are permitted provided that the following conditions
>@@ -33,6 +33,7 @@
> #include "DFGOSRExitBase.h"
> #include "FTLAbbreviations.h"
> #include "FTLExitArgumentList.h"
>+#include "FTLExitTimeObjectMaterialization.h"
> #include "FTLExitValue.h"
> #include "FTLFormattedValue.h"
> #include "MethodOfGettingAValueProfile.h"
>@@ -160,6 +161,7 @@ struct OSRExit : public DFG::OSRExitBase
>     unsigned m_patchableCodeOffset;
>     
>     Operands<ExitValue> m_values;
>+    Bag<ExitTimeObjectMaterialization> m_materializations;
>     
>     uint32_t m_stackmapID;
>     
>Index: Source/JavaScriptCore/ftl/FTLOSRExitCompiler.cpp
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLOSRExitCompiler.cpp	(revision 173938)
>+++ Source/JavaScriptCore/ftl/FTLOSRExitCompiler.cpp	(working copy)
>@@ -33,6 +33,7 @@
> #include "FTLExitArgumentForOperand.h"
> #include "FTLJITCode.h"
> #include "FTLOSRExit.h"
>+#include "FTLOperations.h"
> #include "FTLState.h"
> #include "FTLSaveRestore.h"
> #include "LinkBuffer.h"
>@@ -46,6 +47,89 @@ namespace JSC { namespace FTL {
> 
> using namespace DFG;
> 
>+static void compileRecovery(
>+    CCallHelpers& jit, const ExitValue& value, StackMaps::Record* record, StackMaps& stackmaps,
>+    char* registerScratch,
>+    const HashMap<ExitTimeObjectMaterialization*, EncodedJSValue*>& materializationToPointer)
>+{
>+    switch (value.kind()) {
>+    case ExitValueDead:
>+        jit.move(MacroAssembler::TrustedImm64(JSValue::encode(jsUndefined())), GPRInfo::regT0);
>+        break;
>+            
>+    case ExitValueConstant:
>+        jit.move(MacroAssembler::TrustedImm64(JSValue::encode(value.constant())), GPRInfo::regT0);
>+        break;
>+            
>+    case ExitValueArgument:
>+        record->locations[value.exitArgument().argument()].restoreInto(
>+            jit, stackmaps, registerScratch, GPRInfo::regT0);
>+        break;
>+            
>+    case ExitValueInJSStack:
>+    case ExitValueInJSStackAsInt32:
>+    case ExitValueInJSStackAsInt52:
>+    case ExitValueInJSStackAsDouble:
>+        jit.load64(AssemblyHelpers::addressFor(value.virtualRegister()), GPRInfo::regT0);
>+        break;
>+            
>+    case ExitValueArgumentsObjectThatWasNotCreated:
>+        // We can't actually recover this yet, but we can make the stack look sane. This is
>+        // a prerequisite to running the actual arguments recovery.
>+        jit.move(MacroAssembler::TrustedImm64(JSValue::encode(JSValue())), GPRInfo::regT0);
>+        break;
>+            
>+    case ExitValueRecovery:
>+        record->locations[value.rightRecoveryArgument()].restoreInto(
>+            jit, stackmaps, registerScratch, GPRInfo::regT1);
>+        record->locations[value.leftRecoveryArgument()].restoreInto(
>+            jit, stackmaps, registerScratch, GPRInfo::regT0);
>+        switch (value.recoveryOpcode()) {
>+        case AddRecovery:
>+            switch (value.recoveryFormat()) {
>+            case ValueFormatInt32:
>+                jit.add32(GPRInfo::regT1, GPRInfo::regT0);
>+                break;
>+            case ValueFormatInt52:
>+                jit.add64(GPRInfo::regT1, GPRInfo::regT0);
>+                break;
>+            default:
>+                RELEASE_ASSERT_NOT_REACHED();
>+                break;
>+            }
>+            break;
>+        case SubRecovery:
>+            switch (value.recoveryFormat()) {
>+            case ValueFormatInt32:
>+                jit.sub32(GPRInfo::regT1, GPRInfo::regT0);
>+                break;
>+            case ValueFormatInt52:
>+                jit.sub64(GPRInfo::regT1, GPRInfo::regT0);
>+                break;
>+            default:
>+                RELEASE_ASSERT_NOT_REACHED();
>+                break;
>+            }
>+            break;
>+        default:
>+            RELEASE_ASSERT_NOT_REACHED();
>+            break;
>+        }
>+        break;
>+        
>+    case ExitValueMaterializeNewObject:
>+        jit.loadPtr(materializationToPointer.get(value.objectMaterialization()), GPRInfo::regT0);
>+        break;
>+            
>+    default:
>+        RELEASE_ASSERT_NOT_REACHED();
>+        break;
>+    }
>+        
>+    reboxAccordingToFormat(
>+        value.valueFormat(), jit, GPRInfo::regT0, GPRInfo::regT1, GPRInfo::regT2);
>+}
>+
> static void compileStub(
>     unsigned exitID, JITCode* jitCode, OSRExit& exit, VM* vm, CodeBlock* codeBlock)
> {
>@@ -64,13 +148,39 @@ static void compileStub(
> 
>     CCallHelpers jit(vm, codeBlock);
>     
>-    // We need scratch space to save all registers and to build up the JSStack.
>-    // Use a scratch buffer to transfer all values.
>-    ScratchBuffer* scratchBuffer = vm->scratchBufferForSize(sizeof(EncodedJSValue) * exit.m_values.size() + requiredScratchMemorySizeInBytes() + jitCode->unwindInfo.m_registers.size() * sizeof(uint64_t));
>+    // We need scratch space to save all registers, to build up the JS stack, to deal with unwind
>+    // fixup, pointers to all of the objects we materialize, and the elements inside those objects
>+    // that we materialize.
>+    
>+    // Figure out how much space we need for those object allocations.
>+    unsigned numMaterializations = 0;
>+    size_t maxMaterializationNumArguments = 0;
>+    for (ExitTimeObjectMaterialization* materialization : exit.m_materializations) {
>+        numMaterializations++;
>+        
>+        maxMaterializationNumArguments = std::max(
>+            maxMaterializationNumArguments,
>+            materialization->properties().size());
>+    }
>+    
>+    ScratchBuffer* scratchBuffer = vm->scratchBufferForSize(
>+        sizeof(EncodedJSValue) * (
>+            exit.m_values.size() + numMaterializations + maxMaterializationNumArguments) +
>+        requiredScratchMemorySizeInBytes() +
>+        jitCode->unwindInfo.m_registers.size() * sizeof(uint64_t));
>     EncodedJSValue* scratch = scratchBuffer ? static_cast<EncodedJSValue*>(scratchBuffer->dataBuffer()) : 0;
>-    char* registerScratch = bitwise_cast<char*>(scratch + exit.m_values.size());
>+    EncodedJSValue* materializationPointers = scratch + exit.m_values.size();
>+    EncodedJSValue* materializationArguments = materializationPointers + numMaterializations;
>+    char* registerScratch = bitwise_cast<char*>(materializationArguments + maxMaterializationNumArguments);
>     uint64_t* unwindScratch = bitwise_cast<uint64_t*>(registerScratch + requiredScratchMemorySizeInBytes());
>     
>+    HashMap<ExitTimeObjectMaterialization*, EncodedJSValue*> materializationToPointer;
>+    unsigned materializationCount = 0;
>+    for (ExitTimeObjectMaterialization* materialization : exit.m_materializations) {
>+        materializationToPointer.add(
>+            materialization, materializationPointers + materializationCount++);
>+    }
>+    
>     // Note that we come in here, the stack used to be as LLVM left it except that someone called pushToSave().
>     // We don't care about the value they saved. But, we do appreciate the fact that they did it, because we use
>     // that slot for saveAllRegisters().
>@@ -120,86 +230,69 @@ static void compileStub(
>         if (!!exit.m_valueProfile)
>             jit.store64(GPRInfo::regT0, exit.m_valueProfile.getSpecFailBucket(0));
>     }
>-
>-    // Save all state from wherever the exit data tells us it was, into the appropriate place in
>-    // the scratch buffer. This also does the reboxing.
>     
>-    for (unsigned index = exit.m_values.size(); index--;) {
>-        ExitValue value = exit.m_values[index];
>+    // Materialize all objects. Don't materialize an object until all of the objects it needs
>+    // have been materialized.
>+    HashSet<ExitTimeObjectMaterialization*> toMaterialize;
>+    for (ExitTimeObjectMaterialization* materialization : exit.m_materializations)
>+        toMaterialize.add(materialization);
>+    
>+    while (!toMaterialize.isEmpty()) {
>+        int previousToMaterializeSize = toMaterialize.size();
>         
>-        switch (value.kind()) {
>-        case ExitValueDead:
>-            jit.move(MacroAssembler::TrustedImm64(JSValue::encode(jsUndefined())), GPRInfo::regT0);
>-            break;
>-            
>-        case ExitValueConstant:
>-            jit.move(MacroAssembler::TrustedImm64(JSValue::encode(value.constant())), GPRInfo::regT0);
>-            break;
>-            
>-        case ExitValueArgument:
>-            record->locations[value.exitArgument().argument()].restoreInto(
>-                jit, jitCode->stackmaps, registerScratch, GPRInfo::regT0);
>-            break;
>-            
>-        case ExitValueInJSStack:
>-        case ExitValueInJSStackAsInt32:
>-        case ExitValueInJSStackAsInt52:
>-        case ExitValueInJSStackAsDouble:
>-            jit.load64(AssemblyHelpers::addressFor(value.virtualRegister()), GPRInfo::regT0);
>-            break;
>-            
>-        case ExitValueArgumentsObjectThatWasNotCreated:
>-            // We can't actually recover this yet, but we can make the stack look sane. This is
>-            // a prerequisite to running the actual arguments recovery.
>-            jit.move(MacroAssembler::TrustedImm64(JSValue::encode(JSValue())), GPRInfo::regT0);
>-            break;
>-            
>-        case ExitValueRecovery:
>-            record->locations[value.rightRecoveryArgument()].restoreInto(
>-                jit, jitCode->stackmaps, registerScratch, GPRInfo::regT1);
>-            record->locations[value.leftRecoveryArgument()].restoreInto(
>-                jit, jitCode->stackmaps, registerScratch, GPRInfo::regT0);
>-            switch (value.recoveryOpcode()) {
>-            case AddRecovery:
>-                switch (value.recoveryFormat()) {
>-                case ValueFormatInt32:
>-                    jit.add32(GPRInfo::regT1, GPRInfo::regT0);
>-                    break;
>-                case ValueFormatInt52:
>-                    jit.add64(GPRInfo::regT1, GPRInfo::regT0);
>-                    break;
>-                default:
>-                    RELEASE_ASSERT_NOT_REACHED();
>-                    break;
>-                }
>-                break;
>-            case SubRecovery:
>-                switch (value.recoveryFormat()) {
>-                case ValueFormatInt32:
>-                    jit.sub32(GPRInfo::regT1, GPRInfo::regT0);
>-                    break;
>-                case ValueFormatInt52:
>-                    jit.sub64(GPRInfo::regT1, GPRInfo::regT0);
>-                    break;
>-                default:
>-                    RELEASE_ASSERT_NOT_REACHED();
>+        Vector<ExitTimeObjectMaterialization*> worklist;
>+        worklist.appendRange(toMaterialize.begin(), toMaterialize.end());
>+        for (ExitTimeObjectMaterialization* materialization : worklist) {
>+            // Check if we can do anything about this right now.
>+            bool allGood = true;
>+            for (ExitPropertyValue value : materialization->properties()) {
>+                if (!value.value().isObjectMaterialization())
>+                    continue;
>+                if (toMaterialize.contains(value.value().objectMaterialization())) {
>+                    // Gotta skip this one, since one of its fields points to a materialization
>+                    // that hasn't been materialized.
>+                    allGood = false;
>                     break;
>                 }
>-                break;
>-            default:
>-                RELEASE_ASSERT_NOT_REACHED();
>-                break;
>             }
>-            break;
>+            if (!allGood)
>+                continue;
>             
>-        default:
>-            RELEASE_ASSERT_NOT_REACHED();
>-            break;
>+            // All systems go for materializing the object. First we recover the values of all of
>+            // its fields and then we call a function to actually allocate the beast.
>+            for (unsigned propertyIndex = materialization->properties().size(); propertyIndex--;) {
>+                const ExitValue& value = materialization->properties()[propertyIndex].value();
>+                compileRecovery(
>+                    jit, value, record, jitCode->stackmaps, registerScratch,
>+                    materializationToPointer);
>+                jit.storePtr(GPRInfo::regT0, materializationArguments + propertyIndex);
>+            }
>+            
>+            // This call assumes that we don't pass arguments on the stack.
>+            jit.setupArgumentsWithExecState(
>+                CCallHelpers::TrustedImmPtr(materialization),
>+                CCallHelpers::TrustedImmPtr(materializationArguments));
>+            jit.move(CCallHelpers::TrustedImmPtr(bitwise_cast<void*>(operationMaterializeObjectInOSR)), GPRInfo::nonArgGPR0);
>+            jit.call(GPRInfo::nonArgGPR0);
>+            jit.storePtr(GPRInfo::returnValueGPR, materializationToPointer.get(materialization));
>+            
>+            // Let everyone know that we're done.
>+            toMaterialize.remove(materialization);
>         }
>         
>-        reboxAccordingToFormat(
>-            value.valueFormat(), jit, GPRInfo::regT0, GPRInfo::regT1, GPRInfo::regT2);
>-        
>+        // We expect progress! This ensures that we crash rather than looping infinitely if there
>+        // is something broken about this fixpoint. Or, this could happen if we ever violate the
>+        // "materializations form a DAG" rule.
>+        RELEASE_ASSERT(toMaterialize.size() < previousToMaterializeSize);
>+    }
>+
>+    // Save all state from wherever the exit data tells us it was, into the appropriate place in
>+    // the scratch buffer. This also does the reboxing.
>+    
>+    for (unsigned index = exit.m_values.size(); index--;) {
>+        compileRecovery(
>+            jit, exit.m_values[index], record, jitCode->stackmaps, registerScratch,
>+            materializationToPointer);
>         jit.store64(GPRInfo::regT0, scratch + index);
>     }
>     
>Index: Source/JavaScriptCore/ftl/FTLOperations.cpp
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLOperations.cpp	(revision 0)
>+++ Source/JavaScriptCore/ftl/FTLOperations.cpp	(working copy)
>@@ -0,0 +1,98 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#include "config.h"
>+#include "FTLOperations.h"
>+
>+#if ENABLE(FTL_JIT)
>+
>+#include "JSCInlines.h"
>+
>+namespace JSC { namespace FTL {
>+
>+using namespace JSC::DFG;
>+
>+extern "C" JSCell* JIT_OPERATION operationNewObjectWithButterfly(ExecState* exec, Structure* structure)
>+{
>+    VM& vm = exec->vm();
>+    NativeCallFrameTracer tracer(&vm, exec);
>+    
>+    Butterfly* butterfly = Butterfly::create(
>+        vm, nullptr, 0, structure->outOfLineCapacity(), false, IndexingHeader(), 0);
>+    
>+    return JSFinalObject::create(exec, structure, butterfly);
>+}
>+
>+extern "C" JSCell* JIT_OPERATION operationMaterializeObjectInOSR(
>+    ExecState* exec, ExitTimeObjectMaterialization* materialization, EncodedJSValue* values)
>+{
>+    VM& vm = exec->vm();
>+    CodeBlock* codeBlock = exec->codeBlock();
>+
>+    // We cannot GC. We've got pointers in evil places.
>+    DeferGCForAWhile deferGC(vm.heap);
>+    
>+    // In the future, we may have many different kinds of materializations. For now we just
>+    // materialize NewObject.
>+    RELEASE_ASSERT(materialization->type() == PhantomNewObject);
>+    
>+    // First figure out what the structure is.
>+    Structure* structure = nullptr;
>+    for (unsigned i = materialization->properties().size(); i--;) {
>+        const ExitPropertyValue& property = materialization->properties()[i];
>+        if (property.location() != PromotedLocationDescriptor(StructurePLoc))
>+            continue;
>+        
>+        structure = jsCast<Structure*>(JSValue::decode(values[i]));
>+    }
>+    RELEASE_ASSERT(structure);
>+    
>+    // Let's create that object!
>+    JSFinalObject* result = JSFinalObject::create(vm, structure);
>+    
>+    // Now figure out what the heck to populate the object with. Use getPropertiesConcurrently()
>+    // because that happens to be lower-level and more convenient. It doesn't change the
>+    // materialization of the property table. We want to have minimal visible effects on the
>+    // system. Also, don't mind that this is O(n^2). It doesn't matter. We only get here from OSR
>+    // exit.
>+    for (PropertyMapEntry entry : structure->getPropertiesConcurrently()) {
>+        for (unsigned i = materialization->properties().size(); i--;) {
>+            const ExitPropertyValue& property = materialization->properties()[i];
>+            if (property.location().kind() != NamedPropertyPLoc)
>+                continue;
>+            if (codeBlock->identifier(property.location().info()).impl() != entry.key)
>+                continue;
>+            
>+            result->putDirect(vm, entry.offset, JSValue::decode(values[i]));
>+        }
>+    }
>+    
>+    return result;
>+}
>+
>+} } // namespace JSC::FTL
>+
>+#endif // ENABLE(FTL_JIT)
>+
>Index: Source/JavaScriptCore/ftl/FTLOperations.h
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLOperations.h	(revision 0)
>+++ Source/JavaScriptCore/ftl/FTLOperations.h	(working copy)
>@@ -0,0 +1,50 @@
>+/*
>+ * Copyright (C) 2014 Apple Inc. All rights reserved.
>+ *
>+ * Redistribution and use in source and binary forms, with or without
>+ * modification, are permitted provided that the following conditions
>+ * are met:
>+ * 1. Redistributions of source code must retain the above copyright
>+ *    notice, this list of conditions and the following disclaimer.
>+ * 2. Redistributions in binary form must reproduce the above copyright
>+ *    notice, this list of conditions and the following disclaimer in the
>+ *    documentation and/or other materials provided with the distribution.
>+ *
>+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
>+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
>+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
>+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
>+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
>+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
>+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
>+ */
>+
>+#ifndef FTLOperations_h
>+#define FTLOperations_h
>+
>+#if ENABLE(FTL_JIT)
>+
>+#include "DFGOperations.h"
>+#include "FTLExitTimeObjectMaterialization.h"
>+
>+namespace JSC { namespace FTL {
>+
>+extern "C" {
>+
>+JSCell* JIT_OPERATION operationNewObjectWithButterfly(ExecState*, Structure*) WTF_INTERNAL;
>+
>+JSCell* JIT_OPERATION operationMaterializeObjectInOSR(
>+    ExecState*, ExitTimeObjectMaterialization*, EncodedJSValue*) WTF_INTERNAL;
>+
>+} // extern "C"
>+
>+} } // namespace JSC::DFG
>+
>+#endif // ENABLE(FTL_JIT)
>+
>+#endif // FTLOperations_h
>+
>Index: Source/JavaScriptCore/ftl/FTLSwitchCase.h
>===================================================================
>--- Source/JavaScriptCore/ftl/FTLSwitchCase.h	(revision 173938)
>+++ Source/JavaScriptCore/ftl/FTLSwitchCase.h	(working copy)
>@@ -35,6 +35,12 @@ namespace JSC { namespace FTL {
> 
> class SwitchCase {
> public:
>+    SwitchCase()
>+        : m_value(nullptr)
>+        , m_target(nullptr)
>+    {
>+    }
>+
>     SwitchCase(LValue value, LBasicBlock target, Weight weight)
>         : m_value(value)
>         , m_target(target)
>Index: Source/JavaScriptCore/runtime/JSObject.h
>===================================================================
>--- Source/JavaScriptCore/runtime/JSObject.h	(revision 173938)
>+++ Source/JavaScriptCore/runtime/JSObject.h	(working copy)
>@@ -724,8 +724,6 @@ protected:
>     {
>         Base::finishCreation(vm);
>         ASSERT(inherits(info()));
>-        ASSERT(!structure()->outOfLineCapacity());
>-        ASSERT(structure()->isEmpty());
>         ASSERT(prototype().isNull() || Heap::heap(this) == Heap::heap(prototype()));
>         ASSERT(structure()->isObject());
>         ASSERT(classInfo());
>@@ -1052,7 +1050,7 @@ public:
>         return (maxSize - allocationSize(0)) / sizeof(WriteBarrier<Unknown>);
>     }
> 
>-    static JSFinalObject* create(ExecState*, Structure*);
>+    static JSFinalObject* create(ExecState*, Structure*, Butterfly* = nullptr);
>     static JSFinalObject* create(VM&, Structure*);
>     static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype, unsigned inlineCapacity)
>     {
>@@ -1076,15 +1074,16 @@ protected:
> private:
>     friend class LLIntOffsetsExtractor;
> 
>-    explicit JSFinalObject(VM& vm, Structure* structure)
>-        : JSObject(vm, structure)
>+    explicit JSFinalObject(VM& vm, Structure* structure, Butterfly* butterfly = nullptr)
>+        : JSObject(vm, structure, butterfly)
>     {
>     }
> 
>     static const unsigned StructureFlags = JSObject::StructureFlags;
> };
> 
>-inline JSFinalObject* JSFinalObject::create(ExecState* exec, Structure* structure)
>+inline JSFinalObject* JSFinalObject::create(
>+    ExecState* exec, Structure* structure, Butterfly* butterfly)
> {
>     JSFinalObject* finalObject = new (
>         NotNull, 
>@@ -1092,7 +1091,7 @@ inline JSFinalObject* JSFinalObject::cre
>             *exec->heap(),
>             allocationSize(structure->inlineCapacity())
>         )
>-    ) JSFinalObject(exec->vm(), structure);
>+    ) JSFinalObject(exec->vm(), structure, butterfly);
>     finalObject->finishCreation(exec->vm());
>     return finalObject;
> }
>Index: Source/JavaScriptCore/runtime/Structure.cpp
>===================================================================
>--- Source/JavaScriptCore/runtime/Structure.cpp	(revision 173938)
>+++ Source/JavaScriptCore/runtime/Structure.cpp	(working copy)
>@@ -1105,6 +1105,13 @@ PassRefPtr<StructureShape> Structure::to
>     return baseShape.release();
> }
> 
>+bool Structure::canUseForAllocationsOf(Structure* other)
>+{
>+    return inlineCapacity() == other->inlineCapacity()
>+        && storedPrototype() == other->storedPrototype()
>+        && objectInitializationBlob() == other->objectInitializationBlob();
>+}
>+
> void Structure::dump(PrintStream& out) const
> {
>     out.print(RawPointer(this), ":[", classInfo()->className, ", {");
>Index: Source/JavaScriptCore/runtime/Structure.h
>===================================================================
>--- Source/JavaScriptCore/runtime/Structure.h	(revision 173938)
>+++ Source/JavaScriptCore/runtime/Structure.h	(working copy)
>@@ -433,6 +433,10 @@ public:
> 
>     PassRefPtr<StructureShape> toStructureShape(JSValue);
>     
>+    // Determines if the two structures match enough that this one could be used for allocations
>+    // of the other one.
>+    bool canUseForAllocationsOf(Structure*);
>+    
>     void dump(PrintStream&) const;
>     void dumpInContext(PrintStream&, DumpContext*) const;
>     void dumpBrief(PrintStream&, const CString&) const;
>Index: Source/JavaScriptCore/tests/stress/elidable-new-object-roflcopter-then-exit.js
>===================================================================
>--- Source/JavaScriptCore/tests/stress/elidable-new-object-roflcopter-then-exit.js	(revision 0)
>+++ Source/JavaScriptCore/tests/stress/elidable-new-object-roflcopter-then-exit.js	(working copy)
>@@ -0,0 +1,23 @@
>+function sumOfArithSeries(limit) {
>+    return limit * (limit + 1) / 2;
>+}
>+
>+var n = 10000000;
>+
>+var array = [42, "hello"];
>+
>+function foo() {
>+    var result = 0;
>+    var q;
>+    for (var i = 0; i < n; ++i) {
>+        var o = {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: i}}}}}}}}}}}}}}}}}}};
>+        var p = {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: i + 1}}}}}}}}}}}}}}}}}}};
>+        q = array[(i > n - 100) | 0] + 1;
>+        result += o.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f + p.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f;
>+    }
>+    return q + result;
>+}
>+
>+var result = foo();
>+if (result != "hello" + 1 + (sumOfArithSeries(n - 1) + sumOfArithSeries(n)))
>+    throw "Error: bad result: " + result;
>Index: Source/JavaScriptCore/tests/stress/obviously-elidable-new-object-then-exit.js
>===================================================================
>--- Source/JavaScriptCore/tests/stress/obviously-elidable-new-object-then-exit.js	(revision 0)
>+++ Source/JavaScriptCore/tests/stress/obviously-elidable-new-object-then-exit.js	(working copy)
>@@ -0,0 +1,23 @@
>+function sumOfArithSeries(limit) {
>+    return limit * (limit + 1) / 2;
>+}
>+
>+var n = 10000000;
>+
>+var array = [1, "hello"];
>+
>+function foo() {
>+    var result = 0;
>+    var q;
>+    for (var i = 0; i < n; ++i) {
>+        var o = {f: i};
>+        var p = {f: i + 1};
>+        q = array[(i >= n - 100) | 0] + 1;
>+        result += o.f + p.f;
>+    }
>+    return q + result;
>+}
>+
>+var result = foo();
>+if (result != "hello" + 1 + (sumOfArithSeries(n - 1) + sumOfArithSeries(n)))
>+    throw "Error: bad result: " + result;
>Index: Source/WTF/ChangeLog
>===================================================================
>--- Source/WTF/ChangeLog	(revision 173938)
>+++ Source/WTF/ChangeLog	(working copy)
>@@ -1,3 +1,17 @@
>+2014-09-24  Filip Pizlo  <fpizlo@apple.com>
>+
>+        FTL should sink object allocations
>+        https://bugs.webkit.org/show_bug.cgi?id=136330
>+
>+        Reviewed by Oliver Hunt.
>+        
>+        Make it possible to reset a Bag.
>+
>+        * wtf/Bag.h:
>+        (WTF::Bag::Bag):
>+        (WTF::Bag::~Bag):
>+        (WTF::Bag::clear):
>+
> 2014-09-24  Geoffrey Garen  <ggaren@apple.com>
> 
>         Do the bmalloc.
>Index: Source/WTF/wtf/Bag.h
>===================================================================
>--- Source/WTF/wtf/Bag.h	(revision 173938)
>+++ Source/WTF/wtf/Bag.h	(working copy)
>@@ -46,17 +46,23 @@ private:
>     
> public:
>     Bag()
>-        : m_head(0)
>+        : m_head(nullptr)
>     {
>     }
>     
>     ~Bag()
>     {
>+        clear();
>+    }
>+    
>+    void clear()
>+    {
>         while (m_head) {
>             Node* current = m_head;
>             m_head = current->m_next;
>             delete current;
>         }
>+        m_head = nullptr;
>     }
>     
>     template<typename... Args>
>Index: LayoutTests/ChangeLog
>===================================================================
>--- LayoutTests/ChangeLog	(revision 173973)
>+++ LayoutTests/ChangeLog	(working copy)
>@@ -1,3 +1,46 @@
>+2014-09-25  Filip Pizlo  <fpizlo@apple.com>
>+
>+        FTL should sink object allocations
>+        https://bugs.webkit.org/show_bug.cgi?id=136330
>+
>+        Reviewed by Oliver Hunt.
>+
>+        * js/math-denorm.html: Added.
>+        * js/regress/elidable-new-object-tree-expected.txt: Added.
>+        * js/regress/elidable-new-object-tree.html: Added.
>+        * js/regress/obvious-sink-pathology-expected.txt: Added.
>+        * js/regress/obvious-sink-pathology-taken-expected.txt: Added.
>+        * js/regress/obvious-sink-pathology-taken.html: Added.
>+        * js/regress/obvious-sink-pathology.html: Added.
>+        * js/regress/obviously-elidable-new-object-expected.txt: Added.
>+        * js/regress/obviously-elidable-new-object.html: Added.
>+        * js/regress/script-tests/elidable-new-object-tree.js: Added.
>+        (sumOfArithSeries):
>+        (foo):
>+        * js/regress/script-tests/obvious-sink-pathology-taken.js: Added.
>+        (sumOfArithSeries):
>+        (bar):
>+        (foo):
>+        * js/regress/script-tests/obvious-sink-pathology.js: Added.
>+        (sumOfArithSeries):
>+        (bar):
>+        (foo):
>+        * js/regress/script-tests/obviously-elidable-new-object.js: Added.
>+        (sumOfArithSeries):
>+        (foo):
>+        * js/regress/script-tests/sinkable-new-object-taken.js: Added.
>+        (sumOfArithSeries):
>+        (bar):
>+        (foo):
>+        * js/regress/script-tests/sinkable-new-object.js: Added.
>+        (sumOfArithSeries):
>+        (bar):
>+        (foo):
>+        * js/regress/sinkable-new-object-expected.txt: Added.
>+        * js/regress/sinkable-new-object-taken-expected.txt: Added.
>+        * js/regress/sinkable-new-object-taken.html: Added.
>+        * js/regress/sinkable-new-object.html: Added.
>+
> 2014-09-25  Javier Fernandez  <jfernandez@igalia.com>
> 
>         ASSERTION FAILED: columnCount in WebCore::CSSParser::parseGridTemplateAreasRow
>Index: LayoutTests/js/math-denorm.html
>===================================================================
>--- LayoutTests/js/math-denorm.html	(revision 0)
>+++ LayoutTests/js/math-denorm.html	(working copy)
>@@ -0,0 +1,10 @@
>+<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
>+<html>
>+<head>
>+<script src="resources/js-test-pre.js"></script>
>+</head>
>+<body>
>+<script src="script-tests/math-denorm.js"></script>
>+<script src="resources/js-test-post.js"></script>
>+</body>
>+</html>
>Index: LayoutTests/js/regress/elidable-new-object-roflcopter-expected.txt
>===================================================================
>--- LayoutTests/js/regress/elidable-new-object-roflcopter-expected.txt	(revision 0)
>+++ LayoutTests/js/regress/elidable-new-object-roflcopter-expected.txt	(working copy)
>@@ -0,0 +1,10 @@
>+JSRegress/elidable-new-object-roflcopter
>+
>+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
>+
>+
>+PASS no exception thrown
>+PASS successfullyParsed is true
>+
>+TEST COMPLETE
>+
>Index: LayoutTests/js/regress/elidable-new-object-roflcopter.html
>===================================================================
>--- LayoutTests/js/regress/elidable-new-object-roflcopter.html	(revision 0)
>+++ LayoutTests/js/regress/elidable-new-object-roflcopter.html	(working copy)
>@@ -0,0 +1,12 @@
>+<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
>+<html>
>+<head>
>+<script src="../../resources/js-test-pre.js"></script>
>+</head>
>+<body>
>+<script src="../../resources/regress-pre.js"></script>
>+<script src="script-tests/elidable-new-object-roflcopter.js"></script>
>+<script src="../../resources/regress-post.js"></script>
>+<script src="../../resources/js-test-post.js"></script>
>+</body>
>+</html>
>Index: LayoutTests/js/regress/elidable-new-object-tree-expected.txt
>===================================================================
>--- LayoutTests/js/regress/elidable-new-object-tree-expected.txt	(revision 0)
>+++ LayoutTests/js/regress/elidable-new-object-tree-expected.txt	(working copy)
>@@ -0,0 +1,10 @@
>+JSRegress/elidable-new-object-tree
>+
>+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
>+
>+
>+PASS no exception thrown
>+PASS successfullyParsed is true
>+
>+TEST COMPLETE
>+
>Index: LayoutTests/js/regress/elidable-new-object-tree.html
>===================================================================
>--- LayoutTests/js/regress/elidable-new-object-tree.html	(revision 0)
>+++ LayoutTests/js/regress/elidable-new-object-tree.html	(working copy)
>@@ -0,0 +1,12 @@
>+<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
>+<html>
>+<head>
>+<script src="../../resources/js-test-pre.js"></script>
>+</head>
>+<body>
>+<script src="../../resources/regress-pre.js"></script>
>+<script src="script-tests/elidable-new-object-tree.js"></script>
>+<script src="../../resources/regress-post.js"></script>
>+<script src="../../resources/js-test-post.js"></script>
>+</body>
>+</html>
>Index: LayoutTests/js/regress/obvious-sink-pathology-expected.txt
>===================================================================
>--- LayoutTests/js/regress/obvious-sink-pathology-expected.txt	(revision 0)
>+++ LayoutTests/js/regress/obvious-sink-pathology-expected.txt	(working copy)
>@@ -0,0 +1,10 @@
>+JSRegress/obvious-sink-pathology
>+
>+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
>+
>+
>+PASS no exception thrown
>+PASS successfullyParsed is true
>+
>+TEST COMPLETE
>+
>Index: LayoutTests/js/regress/obvious-sink-pathology-taken-expected.txt
>===================================================================
>--- LayoutTests/js/regress/obvious-sink-pathology-taken-expected.txt	(revision 0)
>+++ LayoutTests/js/regress/obvious-sink-pathology-taken-expected.txt	(working copy)
>@@ -0,0 +1,10 @@
>+JSRegress/obvious-sink-pathology-taken
>+
>+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
>+
>+
>+PASS no exception thrown
>+PASS successfullyParsed is true
>+
>+TEST COMPLETE
>+
>Index: LayoutTests/js/regress/obvious-sink-pathology-taken.html
>===================================================================
>--- LayoutTests/js/regress/obvious-sink-pathology-taken.html	(revision 0)
>+++ LayoutTests/js/regress/obvious-sink-pathology-taken.html	(working copy)
>@@ -0,0 +1,12 @@
>+<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
>+<html>
>+<head>
>+<script src="../../resources/js-test-pre.js"></script>
>+</head>
>+<body>
>+<script src="../../resources/regress-pre.js"></script>
>+<script src="script-tests/obvious-sink-pathology-taken.js"></script>
>+<script src="../../resources/regress-post.js"></script>
>+<script src="../../resources/js-test-post.js"></script>
>+</body>
>+</html>
>Index: LayoutTests/js/regress/obvious-sink-pathology.html
>===================================================================
>--- LayoutTests/js/regress/obvious-sink-pathology.html	(revision 0)
>+++ LayoutTests/js/regress/obvious-sink-pathology.html	(working copy)
>@@ -0,0 +1,12 @@
>+<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
>+<html>
>+<head>
>+<script src="../../resources/js-test-pre.js"></script>
>+</head>
>+<body>
>+<script src="../../resources/regress-pre.js"></script>
>+<script src="script-tests/obvious-sink-pathology.js"></script>
>+<script src="../../resources/regress-post.js"></script>
>+<script src="../../resources/js-test-post.js"></script>
>+</body>
>+</html>
>Index: LayoutTests/js/regress/obviously-elidable-new-object-expected.txt
>===================================================================
>--- LayoutTests/js/regress/obviously-elidable-new-object-expected.txt	(revision 0)
>+++ LayoutTests/js/regress/obviously-elidable-new-object-expected.txt	(working copy)
>@@ -0,0 +1,10 @@
>+JSRegress/obviously-elidable-new-object
>+
>+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
>+
>+
>+PASS no exception thrown
>+PASS successfullyParsed is true
>+
>+TEST COMPLETE
>+
>Index: LayoutTests/js/regress/obviously-elidable-new-object.html
>===================================================================
>--- LayoutTests/js/regress/obviously-elidable-new-object.html	(revision 0)
>+++ LayoutTests/js/regress/obviously-elidable-new-object.html	(working copy)
>@@ -0,0 +1,12 @@
>+<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
>+<html>
>+<head>
>+<script src="../../resources/js-test-pre.js"></script>
>+</head>
>+<body>
>+<script src="../../resources/regress-pre.js"></script>
>+<script src="script-tests/obviously-elidable-new-object.js"></script>
>+<script src="../../resources/regress-post.js"></script>
>+<script src="../../resources/js-test-post.js"></script>
>+</body>
>+</html>
>Index: LayoutTests/js/regress/sinkable-new-object-expected.txt
>===================================================================
>--- LayoutTests/js/regress/sinkable-new-object-expected.txt	(revision 0)
>+++ LayoutTests/js/regress/sinkable-new-object-expected.txt	(working copy)
>@@ -0,0 +1,10 @@
>+JSRegress/sinkable-new-object
>+
>+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
>+
>+
>+PASS no exception thrown
>+PASS successfullyParsed is true
>+
>+TEST COMPLETE
>+
>Index: LayoutTests/js/regress/sinkable-new-object-taken-expected.txt
>===================================================================
>--- LayoutTests/js/regress/sinkable-new-object-taken-expected.txt	(revision 0)
>+++ LayoutTests/js/regress/sinkable-new-object-taken-expected.txt	(working copy)
>@@ -0,0 +1,10 @@
>+JSRegress/sinkable-new-object-taken
>+
>+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
>+
>+
>+PASS no exception thrown
>+PASS successfullyParsed is true
>+
>+TEST COMPLETE
>+
>Index: LayoutTests/js/regress/sinkable-new-object-taken.html
>===================================================================
>--- LayoutTests/js/regress/sinkable-new-object-taken.html	(revision 0)
>+++ LayoutTests/js/regress/sinkable-new-object-taken.html	(working copy)
>@@ -0,0 +1,12 @@
>+<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
>+<html>
>+<head>
>+<script src="../../resources/js-test-pre.js"></script>
>+</head>
>+<body>
>+<script src="../../resources/regress-pre.js"></script>
>+<script src="script-tests/sinkable-new-object-taken.js"></script>
>+<script src="../../resources/regress-post.js"></script>
>+<script src="../../resources/js-test-post.js"></script>
>+</body>
>+</html>
>Index: LayoutTests/js/regress/sinkable-new-object.html
>===================================================================
>--- LayoutTests/js/regress/sinkable-new-object.html	(revision 0)
>+++ LayoutTests/js/regress/sinkable-new-object.html	(working copy)
>@@ -0,0 +1,12 @@
>+<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
>+<html>
>+<head>
>+<script src="../../resources/js-test-pre.js"></script>
>+</head>
>+<body>
>+<script src="../../resources/regress-pre.js"></script>
>+<script src="script-tests/sinkable-new-object.js"></script>
>+<script src="../../resources/regress-post.js"></script>
>+<script src="../../resources/js-test-post.js"></script>
>+</body>
>+</html>
>Index: LayoutTests/js/regress/script-tests/elidable-new-object-roflcopter.js
>===================================================================
>--- LayoutTests/js/regress/script-tests/elidable-new-object-roflcopter.js	(revision 0)
>+++ LayoutTests/js/regress/script-tests/elidable-new-object-roflcopter.js	(working copy)
>@@ -0,0 +1,19 @@
>+function sumOfArithSeries(limit) {
>+    return limit * (limit + 1) / 2;
>+}
>+
>+var n = 10000000;
>+
>+function foo() {
>+    var result = 0;
>+    for (var i = 0; i < n; ++i) {
>+        var o = {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: i}}}}}}}}}}}}}}}}}}};
>+        var p = {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: {f: i + 1}}}}}}}}}}}}}}}}}}};
>+        result += o.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f + p.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f.f;
>+    }
>+    return result;
>+}
>+
>+var result = foo();
>+if (result != sumOfArithSeries(n - 1) + sumOfArithSeries(n))
>+    throw "Error: bad result: " + result;
>Index: LayoutTests/js/regress/script-tests/elidable-new-object-tree.js
>===================================================================
>--- LayoutTests/js/regress/script-tests/elidable-new-object-tree.js	(revision 0)
>+++ LayoutTests/js/regress/script-tests/elidable-new-object-tree.js	(working copy)
>@@ -0,0 +1,19 @@
>+function sumOfArithSeries(limit) {
>+    return limit * (limit + 1) / 2;
>+}
>+
>+var n = 10000000;
>+
>+function foo() {
>+    var result = 0;
>+    for (var i = 0; i < n; ++i) {
>+        var o = {f: {f:i}};
>+        var p = {f: {f:i + 1}};
>+        result += o.f.f + p.f.f;
>+    }
>+    return result;
>+}
>+
>+var result = foo();
>+if (result != sumOfArithSeries(n - 1) + sumOfArithSeries(n))
>+    throw "Error: bad result: " + result;
>Index: LayoutTests/js/regress/script-tests/obvious-sink-pathology-taken.js
>===================================================================
>--- LayoutTests/js/regress/script-tests/obvious-sink-pathology-taken.js	(revision 0)
>+++ LayoutTests/js/regress/script-tests/obvious-sink-pathology-taken.js	(working copy)
>@@ -0,0 +1,26 @@
>+function sumOfArithSeries(limit) {
>+    return limit * (limit + 1) / 2;
>+}
>+
>+var n = 10000000;
>+
>+function bar() { }
>+
>+function foo() {
>+    var result = 0;
>+    for (var i = 0; i < n; ++i) {
>+        var o = {f: i};
>+        var p = {f: i + 1};
>+        if (!(i % 100))
>+            bar(o, p);
>+        result += o.f + p.f;
>+    }
>+    return result;
>+}
>+
>+noInline(bar);
>+noInline(foo);
>+
>+var result = foo();
>+if (result != sumOfArithSeries(n - 1) + sumOfArithSeries(n))
>+    throw "Error: bad result: " + result;
>Index: LayoutTests/js/regress/script-tests/obvious-sink-pathology.js
>===================================================================
>--- LayoutTests/js/regress/script-tests/obvious-sink-pathology.js	(revision 0)
>+++ LayoutTests/js/regress/script-tests/obvious-sink-pathology.js	(working copy)
>@@ -0,0 +1,26 @@
>+function sumOfArithSeries(limit) {
>+    return limit * (limit + 1) / 2;
>+}
>+
>+var n = 10000000;
>+
>+function bar() { }
>+
>+function foo(b) {
>+    var result = 0;
>+    for (var i = 0; i < n; ++i) {
>+        var o = {f: i};
>+        var p = {f: i + 1};
>+        if (b)
>+            bar(o, p);
>+        result += o.f + p.f;
>+    }
>+    return result;
>+}
>+
>+noInline(bar);
>+noInline(foo);
>+
>+var result = foo(false);
>+if (result != sumOfArithSeries(n - 1) + sumOfArithSeries(n))
>+    throw "Error: bad result: " + result;
>Index: LayoutTests/js/regress/script-tests/obviously-elidable-new-object.js
>===================================================================
>--- LayoutTests/js/regress/script-tests/obviously-elidable-new-object.js	(revision 0)
>+++ LayoutTests/js/regress/script-tests/obviously-elidable-new-object.js	(working copy)
>@@ -0,0 +1,19 @@
>+function sumOfArithSeries(limit) {
>+    return limit * (limit + 1) / 2;
>+}
>+
>+var n = 10000000;
>+
>+function foo() {
>+    var result = 0;
>+    for (var i = 0; i < n; ++i) {
>+        var o = {f: i};
>+        var p = {f: i + 1};
>+        result += o.f + p.f;
>+    }
>+    return result;
>+}
>+
>+var result = foo();
>+if (result != sumOfArithSeries(n - 1) + sumOfArithSeries(n))
>+    throw "Error: bad result: " + result;
>Index: LayoutTests/js/regress/script-tests/sinkable-new-object-taken.js
>===================================================================
>--- LayoutTests/js/regress/script-tests/sinkable-new-object-taken.js	(revision 0)
>+++ LayoutTests/js/regress/script-tests/sinkable-new-object-taken.js	(working copy)
>@@ -0,0 +1,26 @@
>+function sumOfArithSeries(limit) {
>+    return limit * (limit + 1) / 2;
>+}
>+
>+var n = 10000000;
>+
>+function bar() { }
>+
>+function foo() {
>+    var result = 0;
>+    for (var i = 0; i < n; ++i) {
>+        var o = {f: i};
>+        var p = {f: i + 1};
>+        result += o.f + p.f;
>+        if (!(i % 100))
>+            bar(o, p);
>+    }
>+    return result;
>+}
>+
>+noInline(bar);
>+noInline(foo);
>+
>+var result = foo();
>+if (result != sumOfArithSeries(n - 1) + sumOfArithSeries(n))
>+    throw "Error: bad result: " + result;
>Index: LayoutTests/js/regress/script-tests/sinkable-new-object.js
>===================================================================
>--- LayoutTests/js/regress/script-tests/sinkable-new-object.js	(revision 0)
>+++ LayoutTests/js/regress/script-tests/sinkable-new-object.js	(working copy)
>@@ -0,0 +1,28 @@
>+function sumOfArithSeries(limit) {
>+    return limit * (limit + 1) / 2;
>+}
>+
>+var n = 10000000;
>+
>+function bar() { }
>+
>+function foo(b) {
>+    var result = 0;
>+    for (var i = 0; i < n; ++i) {
>+        var o = {f: i};
>+        var p = {f: i + 1};
>+        if (b) {
>+            bar(o, p);
>+            return;
>+        }
>+        result += o.f + p.f;
>+    }
>+    return result;
>+}
>+
>+noInline(bar);
>+noInline(foo);
>+
>+var result = foo(false);
>+if (result != sumOfArithSeries(n - 1) + sumOfArithSeries(n))
>+    throw "Error: bad result: " + result;

Actions: View | Formatted Diff | Diff

Attachments on bug 136330: 238103 | 238151 | 238154 | 238219 | 238232 | 238317 | 238320 | 238334 | 238343 | 238415 | 238419 | 238425 | 238432 | 238441 | 238487 | 238493 | 238496 | 238508 | 238514 | 238516 | 238577 | 238607 | 238629 | 238668 | 238684 | 238688 | 238689 | 238692