JavaScriptCore-1218.tar.gz

[apple/javascriptcore.git] / dfg / DFGPredictionPropagationPhase.h

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#ifndef DFGPredictionPropagationPhase_h
#define DFGPredictionPropagationPhase_h

#include <wtf/Platform.h>

#if ENABLE(DFG_JIT)

#include "SpeculatedType.h"

namespace JSC { namespace DFG {

class Graph;

// Propagate predictions gathered at heap load sites by the value profiler, and
// from slow path executions, to generate a prediction for each node in the graph.
// This is a crucial phase of compilation, since before running this phase, we
// have no idea what types any node (or most variables) could possibly have, unless
// that node is either a heap load, a call, a GetLocal for an argument, or an
// arithmetic op that had definitely taken slow path. Most nodes (even most
// arithmetic nodes) do not qualify for any of these categories. But after running
// this phase, we'll have full information for the expected type of each node.

bool performPredictionPropagation(Graph&);

// Helper used for FixupPhase for computing the predicted type of a ToPrimitive.
SpeculatedType resultOfToPrimitive(SpeculatedType type);

} } // namespace JSC::DFG::Phase

#endif // ENABLE(DFG_JIT)

#endif // DFGPredictionPropagationPhase_h