1 // Copyright 2011 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 #ifndef V8_ARM_LITHIUM_GAP_RESOLVER_ARM_H_ 29 #define V8_ARM_LITHIUM_GAP_RESOLVER_ARM_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 44 explicit LGapResolver(LCodeGen* owner); 45 46 // Resolve a set of parallel moves, emitting assembler instructions. 47 void Resolve(LParallelMove* parallel_move); 48 49 private: 50 // Build the initial list of moves. 51 void BuildInitialMoveList(LParallelMove* parallel_move); 52 53 // Perform the move at the moves_ index in question (possibly requiring 54 // other moves to satisfy dependencies). 55 void PerformMove(int index); 56 57 // If a cycle is found in the series of moves, save the blocking value to 58 // a scratch register. The cycle must be found by hitting the root of the 59 // depth-first search. 60 void BreakCycle(int index); 61 62 // After a cycle has been resolved, restore the value from the scratch 63 // register to its proper destination. 64 void RestoreValue(); 65 66 // Emit a move and remove it from the move graph. 67 void EmitMove(int index); 68 69 // Verify the move list before performing moves. 70 void Verify(); 71 72 LCodeGen* cgen_; 73 74 // List of moves not yet resolved. 75 ZoneList<LMoveOperands> moves_; 76 77 int root_index_; 78 bool in_cycle_; 79 LOperand* saved_destination_; 80 }; 81 82 } } // namespace v8::internal 83 84 #endif // V8_ARM_LITHIUM_GAP_RESOLVER_ARM_H_ 85