Source/JavaScriptCore/dfg/DFGPhantomCanonicalizationPhase.h

/*
 * Copyright (C) 2014 Apple Inc. All rights reserved.
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#ifndef DFGPhantomCanonicalizationPhase_h
#define DFGPhantomCanonicalizationPhase_h

#if ENABLE(DFG_JIT)

namespace JSC { namespace DFG {

class Graph;

// Replaces all pre-existing Phantoms with Checks or removes them if the Check is unnecessary. If
// the Phantom was necessary (it uses a node that is relevant to OSR) then the Phantom is hoisted
// to just below the node.
//
// This phase is only valid in SSA, because it's only in SSA that Phantoms are ignored for the
// purpose of liveness-at-some-point and are only used for absolute liveness.
//
// This phase makes a lot of things easier, like CFG simplification: you don't have to insert any
// phantoms when jettisoning a CFG edge.

bool performPhantomCanonicalization(Graph&);

} } // namespace JSC::DFG

#endif // ENABLE(DFG_JIT)

#endif // DFGPhantomCanonicalizationPhase_h