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lithium-gap-resolver-arm64.h
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27 
28 #ifndef V8_ARM64_LITHIUM_GAP_RESOLVER_ARM64_H_
29 #define V8_ARM64_LITHIUM_GAP_RESOLVER_ARM64_H_
30 
31 #include "v8.h"
32 
33 #include "lithium.h"
34 
35 namespace v8 {
36 namespace internal {
37 
38 class LCodeGen;
39 class LGapResolver;
40 
41 class 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  // Emit a move from one stack slot to another.
69  void EmitStackSlotMove(int index);
70 
71  // Verify the move list before performing moves.
72  void Verify();
73 
74  LCodeGen* cgen_;
75 
76  // List of moves not yet resolved.
77  ZoneList<LMoveOperands> moves_;
78 
79  int root_index_;
80  bool in_cycle_;
81  LOperand* saved_destination_;
82 
83  // We use the root register as a scratch in a few places. When that happens,
84  // this flag is set to indicate that it needs to be restored.
85  bool need_to_restore_root_;
86 };
87 
88 } } // namespace v8::internal
89 
90 #endif // V8_ARM64_LITHIUM_GAP_RESOLVER_ARM64_H_
#define BASE_EMBEDDED
Definition: allocation.h:68