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27
28#ifndef V8_MIPS_LITHIUM_GAP_RESOLVER_MIPS_H_
29#define V8_MIPS_LITHIUM_GAP_RESOLVER_MIPS_H_
30
31#include "v8.h"
32
33#include "lithium.h"
34
35namespace v8 {
36namespace internal {
37
38class LCodeGen;
39class LGapResolver;
40
41class LGapResolver BASE_EMBEDDED {
42 public:
43  explicit LGapResolver(LCodeGen* owner);
44
45  // Resolve a set of parallel moves, emitting assembler instructions.
46  void Resolve(LParallelMove* parallel_move);
47
48 private:
49  // Build the initial list of moves.
50  void BuildInitialMoveList(LParallelMove* parallel_move);
51
52  // Perform the move at the moves_ index in question (possibly requiring
53  // other moves to satisfy dependencies).
54  void PerformMove(int index);
55
56  // If a cycle is found in the series of moves, save the blocking value to
57  // a scratch register.  The cycle must be found by hitting the root of the
58  // depth-first search.
59  void BreakCycle(int index);
60
61  // After a cycle has been resolved, restore the value from the scratch
62  // register to its proper destination.
63  void RestoreValue();
64
65  // Emit a move and remove it from the move graph.
66  void EmitMove(int index);
67
68  // Verify the move list before performing moves.
69  void Verify();
70
71  LCodeGen* cgen_;
72
73  // List of moves not yet resolved.
74  ZoneList<LMoveOperands> moves_;
75
76  int root_index_;
77  bool in_cycle_;
78  LOperand* saved_destination_;
79};
80
81} }  // namespace v8::internal
82
83#endif  // V8_MIPS_LITHIUM_GAP_RESOLVER_MIPS_H_
84