dfg/DFGTierUpCheckInjectionPhase.cpp

   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 "DFGTierUpCheckInjectionPhase.h"
  28
  29 #if ENABLE(DFG_JIT)
  30
  31 #include "DFGGraph.h"
  32 #include "DFGInsertionSet.h"
  33 #include "DFGPhase.h"
  34 #include "FTLCapabilities.h"
  35 #include "JSCInlines.h"
  36
  37 namespace JSC { namespace DFG {
  38
  39 class TierUpCheckInjectionPhase : public Phase {
  40 public:
  41     TierUpCheckInjectionPhase(Graph& graph)
  42         : Phase(graph, "tier-up check injection")
  43     {
  44     }
  45
  46     bool run()
  47     {
  48         RELEASE_ASSERT(m_graph.m_plan.mode == DFGMode);
  49
  50         if (!Options::useFTLJIT())
  51             return false;
  52
  53         if (m_graph.m_profiledBlock->m_didFailFTLCompilation)
  54             return false;
  55
  56 #if ENABLE(FTL_JIT)
  57         FTL::CapabilityLevel level = FTL::canCompile(m_graph);
  58         if (level == FTL::CannotCompile)
  59             return false;
  60
  61         if (!Options::enableOSREntryToFTL())
  62             level = FTL::CanCompile;
  63
  64         InsertionSet insertionSet(m_graph);
  65         for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) {
  66             BasicBlock* block = m_graph.block(blockIndex);
  67             if (!block)
  68                 continue;
  69
  70             for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) {
  71                 Node* node = block->at(nodeIndex);
  72                 if (node->op() != LoopHint)
  73                     continue;
  74
  75                 // We only put OSR checks for the first LoopHint in the block. Note that
  76                 // more than one LoopHint could happen in cases where we did a lot of CFG
  77                 // simplification in the bytecode parser, but it should be very rare.
  78
  79                 NodeOrigin origin = node->origin;
  80
  81                 if (level != FTL::CanCompileAndOSREnter || origin.semantic.inlineCallFrame) {
  82                     insertionSet.insertNode(
  83                         nodeIndex + 1, SpecNone, CheckTierUpInLoop, origin);
  84                     break;
  85                 }
  86
  87                 bool isAtTop = true;
  88                 for (unsigned subNodeIndex = nodeIndex; subNodeIndex--;) {
  89                     if (!block->at(subNodeIndex)->isSemanticallySkippable()) {
  90                         isAtTop = false;
  91                         break;
  92                     }
  93                 }
  94
  95                 if (!isAtTop) {
  96                     insertionSet.insertNode(
  97                         nodeIndex + 1, SpecNone, CheckTierUpInLoop, origin);
  98                     break;
  99                 }
 100
 101                 insertionSet.insertNode(
 102                     nodeIndex + 1, SpecNone, CheckTierUpAndOSREnter, origin);
 103                 break;
 104             }
 105
 106             if (block->last()->op() == Return) {
 107                 insertionSet.insertNode(
 108                     block->size() - 1, SpecNone, CheckTierUpAtReturn, block->last()->origin);
 109             }
 110
 111             insertionSet.execute(block);
 112         }
 113
 114         m_graph.m_plan.willTryToTierUp = true;
 115         return true;
 116 #else // ENABLE(FTL_JIT)
 117         RELEASE_ASSERT_NOT_REACHED();
 118         return false;
 119 #endif // ENABLE(FTL_JIT)
 120     }
 121 };
 122
 123 bool performTierUpCheckInjection(Graph& graph)
 124 {
 125     SamplingRegion samplingRegion("DFG Tier-up Check Injection");
 126     return runPhase<TierUpCheckInjectionPhase>(graph);
 127 }
 128
 129 } } // namespace JSC::DFG
 130
 131 #endif // ENABLE(DFG_JIT)
 132
 133