bytecode/ArrayProfile.cpp

   1 /*
   2  * Copyright (C) 2012, 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 "ArrayProfile.h"
  28
  29 #include "CodeBlock.h"
  30 #include "JSCInlines.h"
  31 #include <wtf/CommaPrinter.h>
  32 #include <wtf/StringExtras.h>
  33 #include <wtf/StringPrintStream.h>
  34
  35 namespace JSC {
  36
  37 void dumpArrayModes(PrintStream& out, ArrayModes arrayModes)
  38 {
  39     if (!arrayModes) {
  40         out.print("<empty>");
  41         return;
  42     }
  43
  44     if (arrayModes == ALL_ARRAY_MODES) {
  45         out.print("TOP");
  46         return;
  47     }
  48
  49     CommaPrinter comma("|");
  50     if (arrayModes & asArrayModes(NonArray))
  51         out.print(comma, "NonArray");
  52     if (arrayModes & asArrayModes(NonArrayWithInt32))
  53         out.print(comma, "NonArrayWithInt32");
  54     if (arrayModes & asArrayModes(NonArrayWithDouble))
  55         out.print(comma, "NonArrayWithDouble");
  56     if (arrayModes & asArrayModes(NonArrayWithContiguous))
  57         out.print(comma, "NonArrayWithContiguous");
  58     if (arrayModes & asArrayModes(NonArrayWithArrayStorage))
  59         out.print(comma, "NonArrayWithArrayStorage");
  60     if (arrayModes & asArrayModes(NonArrayWithSlowPutArrayStorage))
  61         out.print(comma, "NonArrayWithSlowPutArrayStorage");
  62     if (arrayModes & asArrayModes(ArrayClass))
  63         out.print(comma, "ArrayClass");
  64     if (arrayModes & asArrayModes(ArrayWithUndecided))
  65         out.print(comma, "ArrayWithUndecided");
  66     if (arrayModes & asArrayModes(ArrayWithInt32))
  67         out.print(comma, "ArrayWithInt32");
  68     if (arrayModes & asArrayModes(ArrayWithDouble))
  69         out.print(comma, "ArrayWithDouble");
  70     if (arrayModes & asArrayModes(ArrayWithContiguous))
  71         out.print(comma, "ArrayWithContiguous");
  72     if (arrayModes & asArrayModes(ArrayWithArrayStorage))
  73         out.print(comma, "ArrayWithArrayStorage");
  74     if (arrayModes & asArrayModes(ArrayWithSlowPutArrayStorage))
  75         out.print(comma, "ArrayWithSlowPutArrayStorage");
  76 }
  77
  78 void ArrayProfile::computeUpdatedPrediction(const ConcurrentJITLocker&, CodeBlock* codeBlock)
  79 {
  80     if (!m_lastSeenStructureID)
  81         return;
  82
  83     Structure* lastSeenStructure = codeBlock->heap()->structureIDTable().get(m_lastSeenStructureID);
  84     m_observedArrayModes |= arrayModeFromStructure(lastSeenStructure);
  85
  86     if (!m_didPerformFirstRunPruning
  87         && hasTwoOrMoreBitsSet(m_observedArrayModes)) {
  88         m_observedArrayModes = arrayModeFromStructure(lastSeenStructure);
  89         m_didPerformFirstRunPruning = true;
  90     }
  91
  92     m_mayInterceptIndexedAccesses |=
  93         lastSeenStructure->typeInfo().interceptsGetOwnPropertySlotByIndexEvenWhenLengthIsNotZero();
  94     JSGlobalObject* globalObject = codeBlock->globalObject();
  95     if (!globalObject->isOriginalArrayStructure(lastSeenStructure)
  96         && !globalObject->isOriginalTypedArrayStructure(lastSeenStructure))
  97         m_usesOriginalArrayStructures = false;
  98     m_lastSeenStructureID = 0;
  99 }
 100
 101 CString ArrayProfile::briefDescription(const ConcurrentJITLocker& locker, CodeBlock* codeBlock)
 102 {
 103     computeUpdatedPrediction(locker, codeBlock);
 104     return briefDescriptionWithoutUpdating(locker);
 105 }
 106
 107 CString ArrayProfile::briefDescriptionWithoutUpdating(const ConcurrentJITLocker&)
 108 {
 109     StringPrintStream out;
 110
 111     bool hasPrinted = false;
 112
 113     if (m_observedArrayModes) {
 114         if (hasPrinted)
 115             out.print(", ");
 116         out.print(ArrayModesDump(m_observedArrayModes));
 117         hasPrinted = true;
 118     }
 119
 120     if (m_mayStoreToHole) {
 121         if (hasPrinted)
 122             out.print(", ");
 123         out.print("Hole");
 124         hasPrinted = true;
 125     }
 126
 127     if (m_outOfBounds) {
 128         if (hasPrinted)
 129             out.print(", ");
 130         out.print("OutOfBounds");
 131         hasPrinted = true;
 132     }
 133
 134     if (m_mayInterceptIndexedAccesses) {
 135         if (hasPrinted)
 136             out.print(", ");
 137         out.print("Intercept");
 138         hasPrinted = true;
 139     }
 140
 141     if (m_usesOriginalArrayStructures) {
 142         if (hasPrinted)
 143             out.print(", ");
 144         out.print("Original");
 145         hasPrinted = true;
 146     }
 147
 148     UNUSED_PARAM(hasPrinted);
 149
 150     return out.toCString();
 151 }
 152
 153 } // namespace JSC
 154