1 // Copyright 2014 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_COMPILER_MOVE_OPTIMIZER_ 6 #define V8_COMPILER_MOVE_OPTIMIZER_ 7 8 #include "src/compiler/instruction.h" 9 #include "src/globals.h" 10 #include "src/zone/zone-containers.h" 11 12 namespace v8 { 13 namespace internal { 14 namespace compiler { 15 16 class V8_EXPORT_PRIVATE MoveOptimizer final { 17 public: 18 MoveOptimizer(Zone* local_zone, InstructionSequence* code); 19 void Run(); 20 21 private: 22 typedef ZoneVector<MoveOperands*> MoveOpVector; 23 typedef ZoneVector<Instruction*> Instructions; 24 25 InstructionSequence* code() const { return code_; } 26 Zone* local_zone() const { return local_zone_; } 27 Zone* code_zone() const { return code()->zone(); } 28 MoveOpVector& local_vector() { return local_vector_; } 29 30 // Consolidate moves into the first gap. 31 void CompressGaps(Instruction* instr); 32 33 // Attempt to push down to the last instruction those moves that can. 34 void CompressBlock(InstructionBlock* block); 35 36 // Consolidate moves into the first gap. 37 void CompressMoves(ParallelMove* left, MoveOpVector* right); 38 39 // Push down those moves in the gap of from that do not change the 40 // semantics of the from instruction, nor the semantics of the moves 41 // that remain behind. 42 void MigrateMoves(Instruction* to, Instruction* from); 43 44 void RemoveClobberedDestinations(Instruction* instruction); 45 46 const Instruction* LastInstruction(const InstructionBlock* block) const; 47 48 // Consolidate common moves appearing accross all predecessors of a block. 49 void OptimizeMerge(InstructionBlock* block); 50 void FinalizeMoves(Instruction* instr); 51 52 Zone* const local_zone_; 53 InstructionSequence* const code_; 54 MoveOpVector local_vector_; 55 56 // Reusable buffers for storing operand sets. We need at most two sets 57 // at any given time, so we create two buffers. 58 ZoneVector<InstructionOperand> operand_buffer1; 59 ZoneVector<InstructionOperand> operand_buffer2; 60 61 DISALLOW_COPY_AND_ASSIGN(MoveOptimizer); 62 }; 63 64 } // namespace compiler 65 } // namespace internal 66 } // namespace v8 67 68 #endif // V8_COMPILER_MOVE_OPTIMIZER_ 69