dfg/DFGPredictionPropagationPhase.h

   1 /*
   2  * Copyright (C) 2011 Apple Inc. All rights reserved.
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   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
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   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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  24  */
  25
  26 #ifndef DFGPredictionPropagationPhase_h
  27 #define DFGPredictionPropagationPhase_h
  28
  29 #include <wtf/Platform.h>
  30
  31 #if ENABLE(DFG_JIT)
  32
  33 #include "SpeculatedType.h"
  34
  35 namespace JSC { namespace DFG {
  36
  37 class Graph;
  38
  39 // Propagate predictions gathered at heap load sites by the value profiler, and
  40 // from slow path executions, to generate a prediction for each node in the graph.
  41 // This is a crucial phase of compilation, since before running this phase, we
  42 // have no idea what types any node (or most variables) could possibly have, unless
  43 // that node is either a heap load, a call, a GetLocal for an argument, or an
  44 // arithmetic op that had definitely taken slow path. Most nodes (even most
  45 // arithmetic nodes) do not qualify for any of these categories. But after running
  46 // this phase, we'll have full information for the expected type of each node.
  47
  48 bool performPredictionPropagation(Graph&);
  49
  50 // Helper used for FixupPhase for computing the predicted type of a ToPrimitive.
  51 SpeculatedType resultOfToPrimitive(SpeculatedType type);
  52
  53 } } // namespace JSC::DFG::Phase
  54
  55 #endif // ENABLE(DFG_JIT)
  56
  57 #endif // DFGPredictionPropagationPhase_h