Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1 | // Copyright 2011 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #ifndef V8_CRANKSHAFT_X87_LITHIUM_GAP_RESOLVER_X87_H_ |
| 6 | #define V8_CRANKSHAFT_X87_LITHIUM_GAP_RESOLVER_X87_H_ |
| 7 | |
| 8 | #include "src/crankshaft/lithium.h" |
| 9 | |
| 10 | namespace v8 { |
| 11 | namespace internal { |
| 12 | |
| 13 | class LCodeGen; |
| 14 | class LGapResolver; |
| 15 | |
| 16 | class LGapResolver final BASE_EMBEDDED { |
| 17 | public: |
| 18 | explicit LGapResolver(LCodeGen* owner); |
| 19 | |
| 20 | // Resolve a set of parallel moves, emitting assembler instructions. |
| 21 | void Resolve(LParallelMove* parallel_move); |
| 22 | |
| 23 | private: |
| 24 | // Build the initial list of moves. |
| 25 | void BuildInitialMoveList(LParallelMove* parallel_move); |
| 26 | |
| 27 | // Perform the move at the moves_ index in question (possibly requiring |
| 28 | // other moves to satisfy dependencies). |
| 29 | void PerformMove(int index); |
| 30 | |
| 31 | // Emit any code necessary at the end of a gap move. |
| 32 | void Finish(); |
| 33 | |
| 34 | // Add or delete a move from the move graph without emitting any code. |
| 35 | // Used to build up the graph and remove trivial moves. |
| 36 | void AddMove(LMoveOperands move); |
| 37 | void RemoveMove(int index); |
| 38 | |
| 39 | // Report the count of uses of operand as a source in a not-yet-performed |
| 40 | // move. Used to rebuild use counts. |
| 41 | int CountSourceUses(LOperand* operand); |
| 42 | |
| 43 | // Emit a move and remove it from the move graph. |
| 44 | void EmitMove(int index); |
| 45 | |
| 46 | // Execute a move by emitting a swap of two operands. The move from |
| 47 | // source to destination is removed from the move graph. |
| 48 | void EmitSwap(int index); |
| 49 | |
| 50 | // Ensure that the given operand is not spilled. |
| 51 | void EnsureRestored(LOperand* operand); |
| 52 | |
| 53 | // Return a register that can be used as a temp register, spilling |
| 54 | // something if necessary. |
| 55 | Register EnsureTempRegister(); |
| 56 | |
| 57 | // Return a known free register different from the given one (which could |
| 58 | // be no_reg---returning any free register), or no_reg if there is no such |
| 59 | // register. |
| 60 | Register GetFreeRegisterNot(Register reg); |
| 61 | |
| 62 | // Verify that the state is the initial one, ready to resolve a single |
| 63 | // parallel move. |
| 64 | bool HasBeenReset(); |
| 65 | |
| 66 | // Verify the move list before performing moves. |
| 67 | void Verify(); |
| 68 | |
| 69 | LCodeGen* cgen_; |
| 70 | |
| 71 | // List of moves not yet resolved. |
| 72 | ZoneList<LMoveOperands> moves_; |
| 73 | |
| 74 | // Source and destination use counts for the general purpose registers. |
| 75 | int source_uses_[Register::kNumRegisters]; |
| 76 | int destination_uses_[DoubleRegister::kMaxNumRegisters]; |
| 77 | |
| 78 | // If we had to spill on demand, the currently spilled register's |
| 79 | // allocation index. |
| 80 | int spilled_register_; |
| 81 | }; |
| 82 | |
| 83 | } // namespace internal |
| 84 | } // namespace v8 |
| 85 | |
| 86 | #endif // V8_CRANKSHAFT_X87_LITHIUM_GAP_RESOLVER_X87_H_ |