| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| /** |
| * @author Intel, Pavel A. Ozhdikhin |
| * |
| */ |
| |
| #ifndef _DEADCODEELIMINATOR_H_ |
| #define _DEADCODEELIMINATOR_H_ |
| |
| #include "Stl.h" |
| #include "optpass.h" |
| #include "LoopTree.h" |
| |
| namespace Jitrino { |
| |
| class IRManager; |
| class Inst; |
| class Opnd; |
| class ControlFlowGraph; |
| class Node; |
| class BitSet; |
| |
| ///the structure that holds info to fix infinite loops. |
| class InfiniteLoopsInfo { |
| public: |
| InfiniteLoopsInfo(MemoryManager& mm) : map(mm), hasLoops(false) {} |
| |
| ///loop header to dispatch node mapping |
| StlMap<Node*, Node*> map; |
| |
| ////caches if cfg has loops |
| bool hasLoops; |
| }; |
| |
| class DeadCodeEliminator { |
| public: |
| DeadCodeEliminator(IRManager& irm); |
| void eliminateDeadCode(bool keepEmptyNodes); |
| static void copyPropagate(Inst*); |
| static Opnd* copyPropagate(Opnd*); |
| bool eliminateUnreachableCode(); // returns true if any node is eliminated |
| void removeExtraPseudoThrow(); |
| |
| ///creates a mapping of loop-header to dispatch nodes that can be used later to fix infinite loops |
| static void createLoop2DispatchMapping(ControlFlowGraph& cfg, InfiniteLoopsInfo& info); |
| |
| ///looks for infinite loops in code and adds pseudothrow inst using dispatch node provided by 'info' |
| static void fixInfiniteLoops(IRManager& irm, const InfiniteLoopsInfo& info); |
| |
| private: |
| void sweepInst(Node* node, Inst* inst, BitSet& usefulInstSet, BitSet& usefulVarSet, U_8 *usedInstWidth, U_32 minInstId, U_32 maxInstId, bool canRemoveStvars); |
| void sweepInst1(Node* node, Inst* inst, BitSet& usefulInstSet, BitSet& usefulVarSet, |
| U_32 minInstId, U_32 maxInstId, bool canRemoveStvars); // if we're skipping instWidth |
| static Opnd* findDefiningTemp(Opnd* var); |
| void markEssentialPseudoThrows(LoopNode* loopNode, BitSet& essentialNodes); |
| |
| IRManager& irManager; |
| ControlFlowGraph& flowGraph; |
| Opnd* returnOpnd; |
| bool preserveCriticalEdges; |
| }; |
| |
| } //namespace Jitrino |
| |
| #endif // _DEADCODEELIMINATOR_H_ |