bytecode/DataFormat.h

   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 DataFormat_h
  27 #define DataFormat_h
  28
  29 #include <wtf/Assertions.h>
  30
  31 namespace JSC {
  32
  33 // === DataFormat ===
  34 //
  35 // This enum tracks the current representation in which a value is being held.
  36 // Values may be unboxed primitives (int32, double, or cell), or boxed as a JSValue.
  37 // For boxed values, we may know the type of boxing that has taken place.
  38 // (May also need bool, array, object, string types!)
  39 enum DataFormat {
  40     DataFormatNone = 0,
  41     DataFormatInt32 = 1,
  42     DataFormatInt52 = 2, // Int52's are left-shifted by 16 by default.
  43     DataFormatStrictInt52 = 3, // "Strict" Int52 means it's not shifted.
  44     DataFormatDouble = 4,
  45     DataFormatBoolean = 5,
  46     DataFormatCell = 6,
  47     DataFormatStorage = 7,
  48     DataFormatJS = 8,
  49     DataFormatJSInt32 = DataFormatJS | DataFormatInt32,
  50     DataFormatJSDouble = DataFormatJS | DataFormatDouble,
  51     DataFormatJSCell = DataFormatJS | DataFormatCell,
  52     DataFormatJSBoolean = DataFormatJS | DataFormatBoolean,
  53
  54     // Marker deliminating ordinary data formats and OSR-only data formats.
  55     DataFormatOSRMarker = 32,
  56
  57     // Special data formats used only for OSR.
  58     DataFormatDead = 33, // Implies jsUndefined().
  59     DataFormatArguments = 34 // Implies that the arguments object must be reified.
  60 };
  61
  62 inline const char* dataFormatToString(DataFormat dataFormat)
  63 {
  64     switch (dataFormat) {
  65     case DataFormatNone:
  66         return "None";
  67     case DataFormatInt32:
  68         return "Int32";
  69     case DataFormatInt52:
  70         return "Int52";
  71     case DataFormatStrictInt52:
  72         return "StrictInt52";
  73     case DataFormatDouble:
  74         return "Double";
  75     case DataFormatCell:
  76         return "Cell";
  77     case DataFormatBoolean:
  78         return "Boolean";
  79     case DataFormatStorage:
  80         return "Storage";
  81     case DataFormatJS:
  82         return "JS";
  83     case DataFormatJSInt32:
  84         return "JSInt32";
  85     case DataFormatJSDouble:
  86         return "JSDouble";
  87     case DataFormatJSCell:
  88         return "JSCell";
  89     case DataFormatJSBoolean:
  90         return "JSBoolean";
  91     case DataFormatDead:
  92         return "Dead";
  93     case DataFormatArguments:
  94         return "Arguments";
  95     default:
  96         RELEASE_ASSERT_NOT_REACHED();
  97         return "Unknown";
  98     }
  99 }
 100
 101 inline bool isJSFormat(DataFormat format, DataFormat expectedFormat)
 102 {
 103     ASSERT(expectedFormat & DataFormatJS);
 104     return (format | DataFormatJS) == expectedFormat;
 105 }
 106
 107 inline bool isJSInt32(DataFormat format)
 108 {
 109     return isJSFormat(format, DataFormatJSInt32);
 110 }
 111
 112 inline bool isJSDouble(DataFormat format)
 113 {
 114     return isJSFormat(format, DataFormatJSDouble);
 115 }
 116
 117 inline bool isJSCell(DataFormat format)
 118 {
 119     return isJSFormat(format, DataFormatJSCell);
 120 }
 121
 122 inline bool isJSBoolean(DataFormat format)
 123 {
 124     return isJSFormat(format, DataFormatJSBoolean);
 125 }
 126
 127 }
 128
 129 #endif // DataFormat_h