https://bugs.webkit.org/show_bug.cgi?id=69291

Reviewed by Oliver Hunt.
        
Nodes now have two notion of predictions: the heap prediction, which is
what came directly from value profiling, and the propagator's predictions,
which arise out of abstract interpretation. Every node has a propagator
prediction, but not every node has a heap prediction; and there is no
guarantee that a node that has both will keep them consistent as the
propagator may have additional information available to it.
        
This is performance neutral.

* dfg/DFGGraph.cpp:
(JSC::DFG::Graph::dump):
* dfg/DFGGraph.h:
* dfg/DFGJITCompiler.h:
(JSC::DFG::JITCompiler::getPrediction):
* dfg/DFGNode.h:
(JSC::DFG::Node::Node):
(JSC::DFG::Node::hasHeapPrediction):
(JSC::DFG::Node::getHeapPrediction):
(JSC::DFG::Node::predictHeap):
(JSC::DFG::Node::prediction):
(JSC::DFG::Node::predict):
* dfg/DFGPropagator.cpp:
(JSC::DFG::Propagator::Propagator):
(JSC::DFG::Propagator::setPrediction):
(JSC::DFG::Propagator::mergePrediction):
(JSC::DFG::Propagator::propagateNodePredictions):
(JSC::DFG::Propagator::fixupNode):
(JSC::DFG::Propagator::isPredictedNumerical):
(JSC::DFG::Propagator::logicalNotIsPure):
(JSC::DFG::Propagator::setReplacement):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@96562 268f45cc-cd09-0410-ab3c-d52691b4dbfc