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28 #ifndef V8_IA32_LITHIUM_GAP_RESOLVER_IA32_H_
29 #define V8_IA32_LITHIUM_GAP_RESOLVER_IA32_H_
41 class LGapResolver V8_FINAL BASE_EMBEDDED {
43 explicit LGapResolver(LCodeGen* owner);
45 // Resolve a set of parallel moves, emitting assembler instructions.
46 void Resolve(LParallelMove* parallel_move);
49 // Build the initial list of moves.
50 void BuildInitialMoveList(LParallelMove* parallel_move);
52 // Perform the move at the moves_ index in question (possibly requiring
53 // other moves to satisfy dependencies).
54 void PerformMove(int index);
56 // Emit any code necessary at the end of a gap move.
59 // Add or delete a move from the move graph without emitting any code.
60 // Used to build up the graph and remove trivial moves.
61 void AddMove(LMoveOperands move);
62 void RemoveMove(int index);
64 // Report the count of uses of operand as a source in a not-yet-performed
65 // move. Used to rebuild use counts.
66 int CountSourceUses(LOperand* operand);
68 // Emit a move and remove it from the move graph.
69 void EmitMove(int index);
71 // Execute a move by emitting a swap of two operands. The move from
72 // source to destination is removed from the move graph.
73 void EmitSwap(int index);
75 // Ensure that the given operand is not spilled.
76 void EnsureRestored(LOperand* operand);
78 // Return a register that can be used as a temp register, spilling
79 // something if necessary.
80 Register EnsureTempRegister();
82 // Return a known free register different from the given one (which could
83 // be no_reg---returning any free register), or no_reg if there is no such
85 Register GetFreeRegisterNot(Register reg);
87 // Verify that the state is the initial one, ready to resolve a single
91 // Verify the move list before performing moves.
96 // List of moves not yet resolved.
97 ZoneList<LMoveOperands> moves_;
99 // Source and destination use counts for the general purpose registers.
100 int source_uses_[Register::kMaxNumAllocatableRegisters];
101 int destination_uses_[Register::kMaxNumAllocatableRegisters];
103 // If we had to spill on demand, the currently spilled register's
105 int spilled_register_;
108 } } // namespace v8::internal
110 #endif // V8_IA32_LITHIUM_GAP_RESOLVER_IA32_H_