method check prototype chain
https://bugs.webkit.org/show_bug.cgi?id=89058

Source/JavaScriptCore: 

Reviewed by Gavin Barraclough.
        
This adds the ability to set watchpoints on Structures, and then does
the most modest thing we can do with this ability: the DFG now sets
watchpoints on structure transitions in the prototype chain of method
checks.
        
This appears to be a >1% speed-up on V8.

* bytecode/PutByIdStatus.cpp:
(JSC::PutByIdStatus::computeFromLLInt):
(JSC::PutByIdStatus::computeFor):
* bytecode/StructureSet.h:
(JSC::StructureSet::containsOnly):
(StructureSet):
* bytecode/Watchpoint.cpp:
(JSC::WatchpointSet::WatchpointSet):
(JSC::InlineWatchpointSet::add):
(JSC):
(JSC::InlineWatchpointSet::inflateSlow):
(JSC::InlineWatchpointSet::freeFat):
* bytecode/Watchpoint.h:
(WatchpointSet):
(JSC):
(InlineWatchpointSet):
(JSC::InlineWatchpointSet::InlineWatchpointSet):
(JSC::InlineWatchpointSet::~InlineWatchpointSet):
(JSC::InlineWatchpointSet::hasBeenInvalidated):
(JSC::InlineWatchpointSet::isStillValid):
(JSC::InlineWatchpointSet::startWatching):
(JSC::InlineWatchpointSet::notifyWrite):
(JSC::InlineWatchpointSet::isFat):
(JSC::InlineWatchpointSet::fat):
(JSC::InlineWatchpointSet::inflate):
* dfg/DFGAbstractState.cpp:
(JSC::DFG::AbstractState::execute):
* dfg/DFGByteCodeParser.cpp:
(JSC::DFG::ByteCodeParser::addStructureTransitionCheck):
(ByteCodeParser):
(JSC::DFG::ByteCodeParser::parseBlock):
* dfg/DFGCSEPhase.cpp:
(JSC::DFG::CSEPhase::structureTransitionWatchpointElimination):
(CSEPhase):
(JSC::DFG::CSEPhase::performNodeCSE):
* dfg/DFGCommon.h:
* dfg/DFGGraph.cpp:
(JSC::DFG::Graph::dump):
* dfg/DFGGraph.h:
(JSC::DFG::Graph::isCellConstant):
* dfg/DFGJITCompiler.h:
(JSC::DFG::JITCompiler::addWeakReferences):
(JITCompiler):
* dfg/DFGNode.h:
(JSC::DFG::Node::hasStructure):
(Node):
(JSC::DFG::Node::structure):
* dfg/DFGNodeType.h:
(DFG):
* dfg/DFGPredictionPropagationPhase.cpp:
(JSC::DFG::PredictionPropagationPhase::propagate):
* dfg/DFGRepatch.cpp:
(JSC::DFG::emitPutTransitionStub):
* dfg/DFGSpeculativeJIT64.cpp:
(JSC::DFG::SpeculativeJIT::compile):
* jit/JITStubs.cpp:
(JSC::JITThunks::tryCachePutByID):
* llint/LLIntSlowPaths.cpp:
(JSC::LLInt::LLINT_SLOW_PATH_DECL):
* runtime/Structure.cpp:
(JSC::Structure::Structure):
* runtime/Structure.h:
(JSC::Structure::transitionWatchpointSetHasBeenInvalidated):
(Structure):
(JSC::Structure::transitionWatchpointSetIsStillValid):
(JSC::Structure::addTransitionWatchpoint):
(JSC::Structure::notifyTransitionFromThisStructure):
(JSC::JSCell::setStructure):
* runtime/SymbolTable.cpp:
(JSC::SymbolTableEntry::attemptToWatch):

LayoutTests: 

Rubber stamped by Gavin Barraclough.

* fast/js/dfg-call-method-hit-watchpoint-expected.txt: Added.
* fast/js/dfg-call-method-hit-watchpoint.html: Added.
* fast/js/script-tests/dfg-call-method-hit-watchpoint.js: Added.
(Thingy):
(Thingy.prototype.foo):
(callFoo):
(.Thingy.prototype.foo):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@120499 268f45cc-cd09-0410-ab3c-d52691b4dbfc