| /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- |
| * vim: set ts=8 sts=4 et sw=4 tw=99: |
| * This Source Code Form is subject to the terms of the Mozilla Public |
| * License, v. 2.0. If a copy of the MPL was not distributed with this |
| * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| |
| #ifndef jit_UnreachableCodeElimination_h |
| #define jit_UnreachableCodeElimination_h |
| |
| #include "MIR.h" |
| #include "MIRGraph.h" |
| |
| namespace js { |
| namespace jit { |
| |
| class MIRGraph; |
| |
| class UnreachableCodeElimination |
| { |
| typedef Vector<MBasicBlock *, 16, SystemAllocPolicy> BlockList; |
| |
| MIRGenerator *mir_; |
| MIRGraph &graph_; |
| uint32_t marked_; |
| bool redundantPhis_; |
| bool rerunAliasAnalysis_; |
| |
| bool prunePointlessBranchesAndMarkReachableBlocks(); |
| void checkDependencyAndRemoveUsesFromUnmarkedBlocks(MDefinition *instr); |
| bool removeUnmarkedBlocksAndClearDominators(); |
| bool removeUnmarkedBlocksAndCleanup(); |
| |
| bool enqueue(MBasicBlock *block, BlockList &list); |
| MBasicBlock *optimizableSuccessor(MBasicBlock *block); |
| |
| public: |
| UnreachableCodeElimination(MIRGenerator *mir, MIRGraph &graph) |
| : mir_(mir), |
| graph_(graph), |
| marked_(0), |
| redundantPhis_(false), |
| rerunAliasAnalysis_(false) |
| {} |
| |
| // Walks the graph and discovers what is reachable. Removes everything else. |
| bool analyze(); |
| |
| // Removes any blocks that are not marked. Assumes that these blocks are not |
| // reachable. The parameter |marked| should be the number of blocks that |
| // are marked. |
| bool removeUnmarkedBlocks(size_t marked); |
| }; |
| |
| } /* namespace jit */ |
| } /* namespace js */ |
| |
| #endif /* jit_UnreachableCodeElimination_h */ |