1/* 2 * Copyright (C) 2011 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#ifndef DFGDominators_h 27#define DFGDominators_h 28 29#if ENABLE(DFG_JIT) 30 31#include "DFGAnalysis.h" 32#include "DFGBasicBlock.h" 33#include "DFGCommon.h" 34#include <wtf/FastBitVector.h> 35 36namespace JSC { namespace DFG { 37 38class Graph; 39 40class Dominators : public Analysis<Dominators> { 41public: 42 Dominators(); 43 ~Dominators(); 44 45 void compute(Graph&); 46 47 bool dominates(BlockIndex from, BlockIndex to) const 48 { 49 ASSERT(isValid()); 50 return m_results[to].get(from); 51 } 52 53 bool dominates(BasicBlock* from, BasicBlock* to) const 54 { 55 return dominates(from->index, to->index); 56 } 57 58 void dump(Graph&, PrintStream&) const; 59 60private: 61 bool pruneDominators(Graph&, BlockIndex); 62 63 Vector<FastBitVector> m_results; // For each block, the bitvector of blocks that dominate it. 64 FastBitVector m_scratch; // A temporary bitvector with bit for each block. We recycle this to save new/deletes. 65}; 66 67} } // namespace JSC::DFG 68 69#endif // ENABLE(DFG_JIT) 70 71#endif // DFGDominators_h 72