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27
28#ifndef V8_HYDROGEN_ESCAPE_ANALYSIS_H_
29#define V8_HYDROGEN_ESCAPE_ANALYSIS_H_
30
31#include "allocation.h"
32#include "hydrogen.h"
33
34namespace v8 {
35namespace internal {
36
37
38class HEscapeAnalysisPhase : public HPhase {
39 public:
40  explicit HEscapeAnalysisPhase(HGraph* graph)
41      : HPhase("H_Escape analysis", graph),
42        captured_(0, zone()),
43        number_of_objects_(0),
44        number_of_values_(0),
45        cumulative_values_(0),
46        block_states_(graph->blocks()->length(), zone()) { }
47
48  void Run();
49
50 private:
51  void CollectCapturedValues();
52  bool HasNoEscapingUses(HValue* value, int size);
53  void PerformScalarReplacement();
54  void AnalyzeDataFlow(HInstruction* instr);
55
56  HCapturedObject* NewState(HInstruction* prev);
57  HCapturedObject* NewStateForAllocation(HInstruction* prev);
58  HCapturedObject* NewStateForLoopHeader(HInstruction* prev, HCapturedObject*);
59  HCapturedObject* NewStateCopy(HInstruction* prev, HCapturedObject* state);
60
61  HPhi* NewPhiAndInsert(HBasicBlock* block, HValue* incoming_value, int index);
62
63  HValue* NewMapCheckAndInsert(HCapturedObject* state, HCheckMaps* mapcheck);
64
65  HCapturedObject* StateAt(HBasicBlock* block) {
66    return block_states_.at(block->block_id());
67  }
68
69  void SetStateAt(HBasicBlock* block, HCapturedObject* state) {
70    block_states_.Set(block->block_id(), state);
71  }
72
73  // List of allocations captured during collection phase.
74  ZoneList<HInstruction*> captured_;
75
76  // Number of captured objects on which scalar replacement was done.
77  int number_of_objects_;
78
79  // Number of scalar values tracked during scalar replacement phase.
80  int number_of_values_;
81  int cumulative_values_;
82
83  // Map of block IDs to the data-flow state at block entry during the
84  // scalar replacement phase.
85  ZoneList<HCapturedObject*> block_states_;
86};
87
88
89} }  // namespace v8::internal
90
91#endif  // V8_HYDROGEN_ESCAPE_ANALYSIS_H_
92