dfg/DFGPredictionPropagationPhase.h

   1 /*
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  25
  26 #ifndef DFGPredictionPropagationPhase_h
  27 #define DFGPredictionPropagationPhase_h
  28
  29 #if ENABLE(DFG_JIT)
  30
  31 #include "SpeculatedType.h"
  32
  33 namespace JSC { namespace DFG {
  34
  35 class Graph;
  36
  37 // Propagate predictions gathered at heap load sites by the value profiler, and
  38 // from slow path executions, to generate a prediction for each node in the graph.
  39 // This is a crucial phase of compilation, since before running this phase, we
  40 // have no idea what types any node (or most variables) could possibly have, unless
  41 // that node is either a heap load, a call, a GetLocal for an argument, or an
  42 // arithmetic op that had definitely taken slow path. Most nodes (even most
  43 // arithmetic nodes) do not qualify for any of these categories. But after running
  44 // this phase, we'll have full information for the expected type of each node.
  45
  46 bool performPredictionPropagation(Graph&);
  47
  48 // Helper used for FixupPhase for computing the predicted type of a ToPrimitive.
  49 SpeculatedType resultOfToPrimitive(SpeculatedType);
  50
  51 } } // namespace JSC::DFG::Phase
  52
  53 #endif // ENABLE(DFG_JIT)
  54
  55 #endif // DFGPredictionPropagationPhase_h