src/hydrogen-mark-deoptimize.cc

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#include "hydrogen-mark-deoptimize.h"

namespace v8 {
namespace internal {

void HMarkDeoptimizeOnUndefinedPhase::Run() {
  const ZoneList<HPhi*>* phi_list = graph()->phi_list();
  for (int i = 0; i < phi_list->length(); i++) {
    HPhi* phi = phi_list->at(i);
    if (phi->CheckFlag(HValue::kAllowUndefinedAsNaN)) {
      for (HUseIterator it(phi->uses()); !it.Done(); it.Advance()) {
        HValue* use_value = it.value();
        if (!use_value->CheckFlag(HValue::kAllowUndefinedAsNaN)) {
          ProcessPhi(phi);
          break;
        }
      }
    }
  }
}


void HMarkDeoptimizeOnUndefinedPhase::ProcessPhi(HPhi* phi) {
  ASSERT(phi->CheckFlag(HValue::kAllowUndefinedAsNaN));
  ASSERT(worklist_.is_empty());

  // Push the phi onto the worklist
  phi->ClearFlag(HValue::kAllowUndefinedAsNaN);
  worklist_.Add(phi, zone());

  // Process all phis that can reach this phi
  while (!worklist_.is_empty()) {
    phi = worklist_.RemoveLast();
    for (int i = phi->OperandCount() - 1; i >= 0; --i) {
      HValue* input = phi->OperandAt(i);
      if (input->IsPhi() && input->CheckFlag(HValue::kAllowUndefinedAsNaN)) {
        input->ClearFlag(HValue::kAllowUndefinedAsNaN);
        worklist_.Add(HPhi::cast(input), zone());
      }
    }
  }
}

} }  // namespace v8::internal