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#include <wtf/Platform.h> 30 31#if ENABLE(DFG_JIT) 32 33#include "DFGCommon.h" 34#include <wtf/FastBitVector.h> 35 36namespace JSC { namespace DFG { 37 38class Graph; 39 40class Dominators { 41public: 42 Dominators(); 43 ~Dominators(); 44 45 void compute(Graph& graph); 46 void invalidate() 47 { 48 m_valid = false; 49 } 50 void computeIfNecessary(Graph& graph) 51 { 52 if (m_valid) 53 return; 54 compute(graph); 55 } 56 57 bool isValid() const { return m_valid; } 58 59 bool dominates(BlockIndex from, BlockIndex to) const 60 { 61 ASSERT(isValid()); 62 return m_results[to].get(from); 63 } 64 65private: 66 bool iterateForBlock(Graph& graph, BlockIndex); 67 68 Vector<FastBitVector> m_results; 69 FastBitVector m_scratch; 70 bool m_valid; 71}; 72 73} } // namespace JSC::DFG 74 75#endif // ENABLE(DFG_JIT) 76 77#endif // DFGDominators_h 78