dfg/DFGStaticExecutionCountEstimationPhase.h

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  25
  26 #ifndef DFGStaticExecutionCountEstimationPhase_h
  27 #define DFGStaticExecutionCountEstimationPhase_h
  28
  29 #if ENABLE(DFG_JIT)
  30
  31 namespace JSC { namespace DFG {
  32
  33 class Graph;
  34
  35 // Estimate execution counts (branch execution counts, in particular) based on
  36 // presently available static information. This phase is important because
  37 // subsequent CFG transformations, such as OSR entrypoint creation, perturb our
  38 // ability to do accurate static estimations. Hence we lock in the estimates early.
  39 // Ideally, we would have dynamic information, but we don't right now, so this is as
  40 // good as it gets.
  41 //
  42 // It's worth noting that if we didn't have this phase, then the static estimation
  43 // would be perfomed by LLVM instead. It's worth trying to make this phase perform
  44 // the estimates using the same heuristics that LLVM would use.
  45
  46 bool performStaticExecutionCountEstimation(Graph&);
  47
  48 } } // namespace JSC::DFG
  49
  50 #endif // ENABLE(DFG_JIT)
  51
  52 #endif // DFGStaticExecutionCountEstimationPhase_h
  53