https://bugs.webkit.org/show_bug.cgi?id=118835

Reviewed by Oliver Hunt.

This separates AbstractState into two things:

- InPlaceAbstractState, which can tell you the abstract state of anything you
  might care about, and uses the old AbstractState's algorithms and data
  structures for doing so.

- AbstractInterpreter<AbstractStateType>, which can execute a DFG::Node* with
  respect to an AbstractStateType. Currently we always use
  AbstractStateType = InPlaceAbstractState. But we could drop in an other
  class that supports basic primitives like forNode() and variables().

This is important because:

- We want to hoist things out of loops.

- We don't know what things rely on what type checks.

- We only want to hoist type checks out of loops if they aren't clobbered.

- We may want to still hoist things that depended on those type checks, if it's
  safe to do those things based on the CFA state at the tail of the loop
  pre-header.

- We don't want things to rely on their type checks by way of a token, because
  that's just weird.

So, we want to be able to have a special form of the CFA that can
incrementally update a basic block's state-at-tail, and we want to be able to
do this for multiple blocks simultaneously. This requires *not* storing the
per-node state in the nodes themselves, but instead using the at-tail HashMap
directly.

Hence we need to have a way of making the abstract interpreter (i.e.
AbstractState::execute) polymorphic with respect to state representation. Put
another way, we need to separate the way that abstract state is represented
from the way DFG IR is abstractly interpreted.

* JavaScriptCore.xcodeproj/project.pbxproj:
* dfg/DFGAbstractInterpreter.h: Added.
(DFG):
(AbstractInterpreter):
(JSC::DFG::AbstractInterpreter::forNode):
(JSC::DFG::AbstractInterpreter::variables):
(JSC::DFG::AbstractInterpreter::needsTypeCheck):
(JSC::DFG::AbstractInterpreter::filterEdgeByUse):
(JSC::DFG::AbstractInterpreter::filter):
(JSC::DFG::AbstractInterpreter::filterArrayModes):
(JSC::DFG::AbstractInterpreter::filterByValue):
(JSC::DFG::AbstractInterpreter::trySetConstant):
(JSC::DFG::AbstractInterpreter::filterByType):
* dfg/DFGAbstractInterpreterInlines.h: Added.
(DFG):
(JSC::DFG::::AbstractInterpreter):
(JSC::DFG::::~AbstractInterpreter):
(JSC::DFG::::booleanResult):
(JSC::DFG::::startExecuting):
(JSC::DFG::::executeEdges):
(JSC::DFG::::verifyEdge):
(JSC::DFG::::verifyEdges):
(JSC::DFG::::executeEffects):
(JSC::DFG::::execute):
(JSC::DFG::::clobberWorld):
(JSC::DFG::::clobberCapturedVars):
(JSC::DFG::::clobberStructures):
(JSC::DFG::::dump):
(JSC::DFG::::filter):
(JSC::DFG::::filterArrayModes):
(JSC::DFG::::filterByValue):
* dfg/DFGAbstractState.cpp: Removed.
* dfg/DFGAbstractState.h: Removed.
* dfg/DFGArgumentsSimplificationPhase.cpp:
* dfg/DFGCFAPhase.cpp:
(JSC::DFG::CFAPhase::CFAPhase):
(JSC::DFG::CFAPhase::performBlockCFA):
(CFAPhase):
* dfg/DFGCFGSimplificationPhase.cpp:
* dfg/DFGConstantFoldingPhase.cpp:
(JSC::DFG::ConstantFoldingPhase::ConstantFoldingPhase):
(JSC::DFG::ConstantFoldingPhase::foldConstants):
(ConstantFoldingPhase):
* dfg/DFGInPlaceAbstractState.cpp: Added.
(DFG):
(JSC::DFG::InPlaceAbstractState::InPlaceAbstractState):
(JSC::DFG::InPlaceAbstractState::~InPlaceAbstractState):
(JSC::DFG::InPlaceAbstractState::beginBasicBlock):
(JSC::DFG::setLiveValues):
(JSC::DFG::InPlaceAbstractState::initialize):
(JSC::DFG::InPlaceAbstractState::endBasicBlock):
(JSC::DFG::InPlaceAbstractState::reset):
(JSC::DFG::InPlaceAbstractState::mergeStateAtTail):
(JSC::DFG::InPlaceAbstractState::merge):
(JSC::DFG::InPlaceAbstractState::mergeToSuccessors):
(JSC::DFG::InPlaceAbstractState::mergeVariableBetweenBlocks):
* dfg/DFGInPlaceAbstractState.h: Added.
(DFG):
(InPlaceAbstractState):
(JSC::DFG::InPlaceAbstractState::forNode):
(JSC::DFG::InPlaceAbstractState::variables):
(JSC::DFG::InPlaceAbstractState::block):
(JSC::DFG::InPlaceAbstractState::didClobber):
(JSC::DFG::InPlaceAbstractState::isValid):
(JSC::DFG::InPlaceAbstractState::setDidClobber):
(JSC::DFG::InPlaceAbstractState::setIsValid):
(JSC::DFG::InPlaceAbstractState::setBranchDirection):
(JSC::DFG::InPlaceAbstractState::setFoundConstants):
(JSC::DFG::InPlaceAbstractState::haveStructures):
(JSC::DFG::InPlaceAbstractState::setHaveStructures):
* dfg/DFGMergeMode.h: Added.
(DFG):
* dfg/DFGSpeculativeJIT.cpp:
(JSC::DFG::SpeculativeJIT::SpeculativeJIT):
(JSC::DFG::SpeculativeJIT::backwardTypeCheck):
(JSC::DFG::SpeculativeJIT::compileCurrentBlock):
(JSC::DFG::SpeculativeJIT::compileToStringOnCell):
(JSC::DFG::SpeculativeJIT::speculateStringIdentAndLoadStorage):
(JSC::DFG::SpeculativeJIT::speculateStringObject):
(JSC::DFG::SpeculativeJIT::speculateStringOrStringObject):
* dfg/DFGSpeculativeJIT.h:
(JSC::DFG::SpeculativeJIT::needsTypeCheck):
(SpeculativeJIT):
* dfg/DFGSpeculativeJIT32_64.cpp:
(JSC::DFG::SpeculativeJIT::fillSpeculateIntInternal):
(JSC::DFG::SpeculativeJIT::fillSpeculateDouble):
(JSC::DFG::SpeculativeJIT::fillSpeculateCell):
(JSC::DFG::SpeculativeJIT::fillSpeculateBoolean):
* dfg/DFGSpeculativeJIT64.cpp:
(JSC::DFG::SpeculativeJIT::fillSpeculateIntInternal):
(JSC::DFG::SpeculativeJIT::fillSpeculateDouble):
(JSC::DFG::SpeculativeJIT::fillSpeculateCell):
(JSC::DFG::SpeculativeJIT::fillSpeculateBoolean):
* ftl/FTLLowerDFGToLLVM.cpp:
(FTL):
(JSC::FTL::LowerDFGToLLVM::LowerDFGToLLVM):
(JSC::FTL::LowerDFGToLLVM::compileNode):
(JSC::FTL::LowerDFGToLLVM::appendTypeCheck):
(JSC::FTL::LowerDFGToLLVM::speculate):
(JSC::FTL::LowerDFGToLLVM::speculateNumber):
(JSC::FTL::LowerDFGToLLVM::speculateRealNumber):
(LowerDFGToLLVM):

Conflicts:
	Source/JavaScriptCore/JavaScriptCore.xcodeproj/project.pbxproj

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@153282 268f45cc-cd09-0410-ab3c-d52691b4dbfc