Source/JavaScriptCore/dfg/DFGStructureRegistrationPhase.h

/*
 * Copyright (C) 2014 Apple Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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#ifndef DFGStructureRegistrationPhase_h
#define DFGStructureRegistrationPhase_h

#if ENABLE(DFG_JIT)

namespace JSC { namespace DFG {

class Graph;

// Registers any structures we know about as weak references, and sets watchpoints on any
// such structures that we know of that are currently watchable. It's somewhat
// counterintuitive, but this ends up being the cleanest and most effective way of reducing
// structure checks on terminal structures:
//
// - We used to only set watchpoints on watchable structures if we knew that this would
//   remove a structure check. Experiments show that switching from that, to blindly
//   setting watchpoints on all watchable structures, was not a regression.
//
// - It makes abstract interpretation a whole lot easier. We just assume that watchable
//   structures are unclobberable without having to do any other logic.

bool performStructureRegistration(Graph&);

} } // namespace JSC::DFG

#endif // ENABLE(DFG_JIT)

#endif // DFGStructureRegistrationPhase_h