src/hydrogen-escape-analysis.cc

// Copyright 2013 the V8 project authors. All rights reserved.
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#include "hydrogen-escape-analysis.h"

namespace v8 {
namespace internal {


void HEscapeAnalysisPhase::CollectIfNoEscapingUses(HInstruction* instr) {
  for (HUseIterator it(instr->uses()); !it.Done(); it.Advance()) {
    HValue* use = it.value();
    if (use->HasEscapingOperandAt(it.index())) {
      if (FLAG_trace_escape_analysis) {
        PrintF("#%d (%s) escapes through #%d (%s) @%d\n", instr->id(),
               instr->Mnemonic(), use->id(), use->Mnemonic(), it.index());
      }
      return;
    }
  }
  if (FLAG_trace_escape_analysis) {
    PrintF("#%d (%s) is being captured\n", instr->id(), instr->Mnemonic());
  }
  captured_.Add(instr, zone());
}


void HEscapeAnalysisPhase::CollectCapturedValues() {
  int block_count = graph()->blocks()->length();
  for (int i = 0; i < block_count; ++i) {
    HBasicBlock* block = graph()->blocks()->at(i);
    for (HInstructionIterator it(block); !it.Done(); it.Advance()) {
      HInstruction* instr = it.Current();
      if (instr->IsAllocate() || instr->IsAllocateObject()) {
        CollectIfNoEscapingUses(instr);
      }
    }
  }
}


} }  // namespace v8::internal