1/* 2 * Copyright (C) 2013, 2014 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#include "config.h" 27#include "DFGSSALoweringPhase.h" 28 29#if ENABLE(DFG_JIT) 30 31#include "DFGBasicBlockInlines.h" 32#include "DFGGraph.h" 33#include "DFGInsertionSet.h" 34#include "DFGPhase.h" 35#include "JSCInlines.h" 36 37namespace JSC { namespace DFG { 38 39class SSALoweringPhase : public Phase { 40 static const bool verbose = false; 41 42public: 43 SSALoweringPhase(Graph& graph) 44 : Phase(graph, "SSA lowering") 45 , m_insertionSet(graph) 46 { 47 } 48 49 bool run() 50 { 51 RELEASE_ASSERT(m_graph.m_form == SSA); 52 53 for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) { 54 m_block = m_graph.block(blockIndex); 55 if (!m_block) 56 continue; 57 for (m_nodeIndex = 0; m_nodeIndex < m_block->size(); ++m_nodeIndex) { 58 m_node = m_block->at(m_nodeIndex); 59 handleNode(); 60 } 61 m_insertionSet.execute(m_block); 62 } 63 64 return true; 65 } 66 67private: 68 void handleNode() 69 { 70 switch (m_node->op()) { 71 case GetByVal: 72 lowerBoundsCheck(m_node->child1(), m_node->child2(), m_node->child3()); 73 break; 74 75 case PutByVal: 76 case PutByValDirect: { 77 Edge base = m_graph.varArgChild(m_node, 0); 78 Edge index = m_graph.varArgChild(m_node, 1); 79 Edge storage = m_graph.varArgChild(m_node, 3); 80 if (lowerBoundsCheck(base, index, storage)) 81 break; 82 83 if (m_node->arrayMode().typedArrayType() != NotTypedArray && m_node->arrayMode().isOutOfBounds()) { 84 Node* length = m_insertionSet.insertNode( 85 m_nodeIndex, SpecInt32, GetArrayLength, m_node->origin, 86 OpInfo(m_node->arrayMode().asWord()), base, storage); 87 88 m_graph.varArgChild(m_node, 4) = Edge(length, KnownInt32Use); 89 break; 90 } 91 break; 92 } 93 94 default: 95 break; 96 } 97 } 98 99 bool lowerBoundsCheck(Edge base, Edge index, Edge storage) 100 { 101 if (!m_node->arrayMode().permitsBoundsCheckLowering()) 102 return false; 103 104 if (!m_node->arrayMode().lengthNeedsStorage()) 105 storage = Edge(); 106 107 Node* length = m_insertionSet.insertNode( 108 m_nodeIndex, SpecInt32, GetArrayLength, m_node->origin, 109 OpInfo(m_node->arrayMode().asWord()), base, storage); 110 m_insertionSet.insertNode( 111 m_nodeIndex, SpecInt32, CheckInBounds, m_node->origin, 112 index, Edge(length, KnownInt32Use)); 113 return true; 114 } 115 116 InsertionSet m_insertionSet; 117 BasicBlock* m_block; 118 unsigned m_nodeIndex; 119 Node* m_node; 120}; 121 122bool performSSALowering(Graph& graph) 123{ 124 SamplingRegion samplingRegion("DFG SSA Lowering Phase"); 125 return runPhase<SSALoweringPhase>(graph); 126} 127 128} } // namespace JSC::DFG 129 130#endif // ENABLE(DFG_JIT) 131 132