dfg/DFGInvalidationPointInjectionPhase.cpp

   1 /*
   2  * Copyright (C) 2013 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 "DFGInvalidationPointInjectionPhase.h"
  28
  29 #if ENABLE(DFG_JIT)
  30
  31 #include "DFGClobberize.h"
  32 #include "DFGGraph.h"
  33 #include "DFGInsertionSet.h"
  34 #include "DFGPhase.h"
  35 #include "JSCInlines.h"
  36
  37 namespace JSC { namespace DFG {
  38
  39 class InvalidationPointInjectionPhase : public Phase {
  40     static const bool verbose = false;
  41
  42 public:
  43     InvalidationPointInjectionPhase(Graph& graph)
  44         : Phase(graph, "invalidation point injection")
  45         , m_insertionSet(graph)
  46     {
  47     }
  48
  49     bool run()
  50     {
  51         ASSERT(m_graph.m_form != SSA);
  52
  53         BitVector blocksThatNeedInvalidationPoints;
  54
  55         for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) {
  56             BasicBlock* block = m_graph.block(blockIndex);
  57             if (!block)
  58                 continue;
  59
  60             for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex)
  61                 handle(nodeIndex, block->at(nodeIndex));
  62
  63             // Note: this assumes that control flow occurs at bytecode instruction boundaries.
  64             if (m_originThatHadFire.isSet()) {
  65                 for (unsigned i = block->numSuccessors(); i--;)
  66                     blocksThatNeedInvalidationPoints.set(block->successor(i)->index);
  67             }
  68
  69             m_insertionSet.execute(block);
  70         }
  71
  72         for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) {
  73             if (!blocksThatNeedInvalidationPoints.get(blockIndex))
  74                 continue;
  75
  76             BasicBlock* block = m_graph.block(blockIndex);
  77             insertInvalidationCheck(0, block->at(0));
  78             m_insertionSet.execute(block);
  79         }
  80
  81         return true;
  82     }
  83
  84 private:
  85     void handle(unsigned nodeIndex, Node* node)
  86     {
  87         if (m_originThatHadFire.isSet() && m_originThatHadFire != node->origin.forExit) {
  88             insertInvalidationCheck(nodeIndex, node);
  89             m_originThatHadFire = CodeOrigin();
  90         }
  91
  92         if (writesOverlap(m_graph, node, Watchpoint_fire))
  93             m_originThatHadFire = node->origin.forExit;
  94     }
  95
  96     void insertInvalidationCheck(unsigned nodeIndex, Node* node)
  97     {
  98         m_insertionSet.insertNode(nodeIndex, SpecNone, InvalidationPoint, node->origin);
  99     }
 100
 101     CodeOrigin m_originThatHadFire;
 102     InsertionSet m_insertionSet;
 103 };
 104
 105 bool performInvalidationPointInjection(Graph& graph)
 106 {
 107     SamplingRegion samplingRegion("DFG Invalidation Point Injection Phase");
 108     return runPhase<InvalidationPointInjectionPhase>(graph);
 109 }
 110
 111 } } // namespace JSC::DFG
 112
 113 #endif // ENABLE(DFG_JIT)
 114