Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1 | // Copyright 2012 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #ifndef V8_ELEMENTS_KIND_H_ |
| 6 | #define V8_ELEMENTS_KIND_H_ |
| 7 | |
| 8 | #include "src/checks.h" |
| 9 | |
| 10 | namespace v8 { |
| 11 | namespace internal { |
| 12 | |
| 13 | enum ElementsKind { |
| 14 | // The "fast" kind for elements that only contain SMI values. Must be first |
| 15 | // to make it possible to efficiently check maps for this kind. |
| 16 | FAST_SMI_ELEMENTS, |
| 17 | FAST_HOLEY_SMI_ELEMENTS, |
| 18 | |
| 19 | // The "fast" kind for tagged values. Must be second to make it possible to |
| 20 | // efficiently check maps for this and the FAST_SMI_ONLY_ELEMENTS kind |
| 21 | // together at once. |
| 22 | FAST_ELEMENTS, |
| 23 | FAST_HOLEY_ELEMENTS, |
| 24 | |
| 25 | // The "fast" kind for unwrapped, non-tagged double values. |
| 26 | FAST_DOUBLE_ELEMENTS, |
| 27 | FAST_HOLEY_DOUBLE_ELEMENTS, |
| 28 | |
| 29 | // The "slow" kind. |
| 30 | DICTIONARY_ELEMENTS, |
| 31 | SLOPPY_ARGUMENTS_ELEMENTS, |
| 32 | // The "fast" kind for external arrays |
| 33 | EXTERNAL_INT8_ELEMENTS, |
| 34 | EXTERNAL_UINT8_ELEMENTS, |
| 35 | EXTERNAL_INT16_ELEMENTS, |
| 36 | EXTERNAL_UINT16_ELEMENTS, |
| 37 | EXTERNAL_INT32_ELEMENTS, |
| 38 | EXTERNAL_UINT32_ELEMENTS, |
| 39 | EXTERNAL_FLOAT32_ELEMENTS, |
| 40 | EXTERNAL_FLOAT64_ELEMENTS, |
| 41 | EXTERNAL_UINT8_CLAMPED_ELEMENTS, |
| 42 | |
| 43 | // Fixed typed arrays |
| 44 | UINT8_ELEMENTS, |
| 45 | INT8_ELEMENTS, |
| 46 | UINT16_ELEMENTS, |
| 47 | INT16_ELEMENTS, |
| 48 | UINT32_ELEMENTS, |
| 49 | INT32_ELEMENTS, |
| 50 | FLOAT32_ELEMENTS, |
| 51 | FLOAT64_ELEMENTS, |
| 52 | UINT8_CLAMPED_ELEMENTS, |
| 53 | |
| 54 | // Derived constants from ElementsKind |
| 55 | FIRST_ELEMENTS_KIND = FAST_SMI_ELEMENTS, |
| 56 | LAST_ELEMENTS_KIND = UINT8_CLAMPED_ELEMENTS, |
| 57 | FIRST_FAST_ELEMENTS_KIND = FAST_SMI_ELEMENTS, |
| 58 | LAST_FAST_ELEMENTS_KIND = FAST_HOLEY_DOUBLE_ELEMENTS, |
| 59 | FIRST_EXTERNAL_ARRAY_ELEMENTS_KIND = EXTERNAL_INT8_ELEMENTS, |
| 60 | LAST_EXTERNAL_ARRAY_ELEMENTS_KIND = EXTERNAL_UINT8_CLAMPED_ELEMENTS, |
| 61 | FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND = UINT8_ELEMENTS, |
| 62 | LAST_FIXED_TYPED_ARRAY_ELEMENTS_KIND = UINT8_CLAMPED_ELEMENTS, |
| 63 | TERMINAL_FAST_ELEMENTS_KIND = FAST_HOLEY_ELEMENTS |
| 64 | }; |
| 65 | |
| 66 | const int kElementsKindCount = LAST_ELEMENTS_KIND - FIRST_ELEMENTS_KIND + 1; |
| 67 | const int kFastElementsKindCount = LAST_FAST_ELEMENTS_KIND - |
| 68 | FIRST_FAST_ELEMENTS_KIND + 1; |
| 69 | |
| 70 | // The number to add to a packed elements kind to reach a holey elements kind |
| 71 | const int kFastElementsKindPackedToHoley = |
| 72 | FAST_HOLEY_SMI_ELEMENTS - FAST_SMI_ELEMENTS; |
| 73 | |
| 74 | int ElementsKindToShiftSize(ElementsKind elements_kind); |
| 75 | int GetDefaultHeaderSizeForElementsKind(ElementsKind elements_kind); |
| 76 | const char* ElementsKindToString(ElementsKind kind); |
| 77 | |
| 78 | inline ElementsKind GetInitialFastElementsKind() { return FAST_SMI_ELEMENTS; } |
| 79 | |
| 80 | ElementsKind GetFastElementsKindFromSequenceIndex(int sequence_number); |
| 81 | int GetSequenceIndexFromFastElementsKind(ElementsKind elements_kind); |
| 82 | |
| 83 | ElementsKind GetNextTransitionElementsKind(ElementsKind elements_kind); |
| 84 | |
| 85 | inline bool IsDictionaryElementsKind(ElementsKind kind) { |
| 86 | return kind == DICTIONARY_ELEMENTS; |
| 87 | } |
| 88 | |
| 89 | |
| 90 | inline bool IsSloppyArgumentsElements(ElementsKind kind) { |
| 91 | return kind == SLOPPY_ARGUMENTS_ELEMENTS; |
| 92 | } |
| 93 | |
| 94 | |
| 95 | inline bool IsExternalArrayElementsKind(ElementsKind kind) { |
| 96 | return kind >= FIRST_EXTERNAL_ARRAY_ELEMENTS_KIND && |
| 97 | kind <= LAST_EXTERNAL_ARRAY_ELEMENTS_KIND; |
| 98 | } |
| 99 | |
| 100 | |
| 101 | inline bool IsTerminalElementsKind(ElementsKind kind) { |
| 102 | return kind == TERMINAL_FAST_ELEMENTS_KIND || |
| 103 | IsExternalArrayElementsKind(kind); |
| 104 | } |
| 105 | |
| 106 | |
| 107 | inline bool IsFixedTypedArrayElementsKind(ElementsKind kind) { |
| 108 | return kind >= FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND && |
| 109 | kind <= LAST_FIXED_TYPED_ARRAY_ELEMENTS_KIND; |
| 110 | } |
| 111 | |
| 112 | |
| 113 | inline bool IsFastElementsKind(ElementsKind kind) { |
| 114 | DCHECK(FIRST_FAST_ELEMENTS_KIND == 0); |
| 115 | return kind <= FAST_HOLEY_DOUBLE_ELEMENTS; |
| 116 | } |
| 117 | |
| 118 | |
| 119 | inline bool IsTransitionElementsKind(ElementsKind kind) { |
| 120 | return IsFastElementsKind(kind) || IsFixedTypedArrayElementsKind(kind); |
| 121 | } |
| 122 | |
| 123 | |
| 124 | inline bool IsFastDoubleElementsKind(ElementsKind kind) { |
| 125 | return kind == FAST_DOUBLE_ELEMENTS || |
| 126 | kind == FAST_HOLEY_DOUBLE_ELEMENTS; |
| 127 | } |
| 128 | |
| 129 | |
| 130 | inline bool IsExternalFloatOrDoubleElementsKind(ElementsKind kind) { |
| 131 | return kind == EXTERNAL_FLOAT64_ELEMENTS || |
| 132 | kind == EXTERNAL_FLOAT32_ELEMENTS; |
| 133 | } |
| 134 | |
| 135 | |
| 136 | inline bool IsFixedFloatElementsKind(ElementsKind kind) { |
| 137 | return kind == FLOAT32_ELEMENTS || kind == FLOAT64_ELEMENTS; |
| 138 | } |
| 139 | |
| 140 | |
| 141 | inline bool IsDoubleOrFloatElementsKind(ElementsKind kind) { |
| 142 | return IsFastDoubleElementsKind(kind) || |
| 143 | IsExternalFloatOrDoubleElementsKind(kind) || |
| 144 | IsFixedFloatElementsKind(kind); |
| 145 | } |
| 146 | |
| 147 | |
| 148 | inline bool IsFastSmiOrObjectElementsKind(ElementsKind kind) { |
| 149 | return kind == FAST_SMI_ELEMENTS || |
| 150 | kind == FAST_HOLEY_SMI_ELEMENTS || |
| 151 | kind == FAST_ELEMENTS || |
| 152 | kind == FAST_HOLEY_ELEMENTS; |
| 153 | } |
| 154 | |
| 155 | |
| 156 | inline bool IsFastSmiElementsKind(ElementsKind kind) { |
| 157 | return kind == FAST_SMI_ELEMENTS || |
| 158 | kind == FAST_HOLEY_SMI_ELEMENTS; |
| 159 | } |
| 160 | |
| 161 | |
| 162 | inline bool IsFastObjectElementsKind(ElementsKind kind) { |
| 163 | return kind == FAST_ELEMENTS || |
| 164 | kind == FAST_HOLEY_ELEMENTS; |
| 165 | } |
| 166 | |
| 167 | |
| 168 | inline bool IsFastHoleyElementsKind(ElementsKind kind) { |
| 169 | return kind == FAST_HOLEY_SMI_ELEMENTS || |
| 170 | kind == FAST_HOLEY_DOUBLE_ELEMENTS || |
| 171 | kind == FAST_HOLEY_ELEMENTS; |
| 172 | } |
| 173 | |
| 174 | |
| 175 | inline bool IsHoleyElementsKind(ElementsKind kind) { |
| 176 | return IsFastHoleyElementsKind(kind) || |
| 177 | kind == DICTIONARY_ELEMENTS; |
| 178 | } |
| 179 | |
| 180 | |
| 181 | inline bool IsFastPackedElementsKind(ElementsKind kind) { |
| 182 | return kind == FAST_SMI_ELEMENTS || |
| 183 | kind == FAST_DOUBLE_ELEMENTS || |
| 184 | kind == FAST_ELEMENTS; |
| 185 | } |
| 186 | |
| 187 | |
| 188 | inline ElementsKind GetPackedElementsKind(ElementsKind holey_kind) { |
| 189 | if (holey_kind == FAST_HOLEY_SMI_ELEMENTS) { |
| 190 | return FAST_SMI_ELEMENTS; |
| 191 | } |
| 192 | if (holey_kind == FAST_HOLEY_DOUBLE_ELEMENTS) { |
| 193 | return FAST_DOUBLE_ELEMENTS; |
| 194 | } |
| 195 | if (holey_kind == FAST_HOLEY_ELEMENTS) { |
| 196 | return FAST_ELEMENTS; |
| 197 | } |
| 198 | return holey_kind; |
| 199 | } |
| 200 | |
| 201 | |
| 202 | inline ElementsKind GetHoleyElementsKind(ElementsKind packed_kind) { |
| 203 | if (packed_kind == FAST_SMI_ELEMENTS) { |
| 204 | return FAST_HOLEY_SMI_ELEMENTS; |
| 205 | } |
| 206 | if (packed_kind == FAST_DOUBLE_ELEMENTS) { |
| 207 | return FAST_HOLEY_DOUBLE_ELEMENTS; |
| 208 | } |
| 209 | if (packed_kind == FAST_ELEMENTS) { |
| 210 | return FAST_HOLEY_ELEMENTS; |
| 211 | } |
| 212 | return packed_kind; |
| 213 | } |
| 214 | |
| 215 | |
| 216 | inline ElementsKind FastSmiToObjectElementsKind(ElementsKind from_kind) { |
| 217 | DCHECK(IsFastSmiElementsKind(from_kind)); |
| 218 | return (from_kind == FAST_SMI_ELEMENTS) |
| 219 | ? FAST_ELEMENTS |
| 220 | : FAST_HOLEY_ELEMENTS; |
| 221 | } |
| 222 | |
| 223 | |
| 224 | inline bool IsSimpleMapChangeTransition(ElementsKind from_kind, |
| 225 | ElementsKind to_kind) { |
| 226 | return (GetHoleyElementsKind(from_kind) == to_kind) || |
| 227 | (IsFastSmiElementsKind(from_kind) && |
| 228 | IsFastObjectElementsKind(to_kind)); |
| 229 | } |
| 230 | |
| 231 | |
| 232 | bool IsMoreGeneralElementsKindTransition(ElementsKind from_kind, |
| 233 | ElementsKind to_kind); |
| 234 | |
| 235 | |
| 236 | inline bool IsTransitionableFastElementsKind(ElementsKind from_kind) { |
| 237 | return IsFastElementsKind(from_kind) && |
| 238 | from_kind != TERMINAL_FAST_ELEMENTS_KIND; |
| 239 | } |
| 240 | |
| 241 | |
| 242 | ElementsKind GetNextMoreGeneralFastElementsKind(ElementsKind elements_kind, |
| 243 | bool allow_only_packed); |
| 244 | |
| 245 | |
| 246 | inline bool CanTransitionToMoreGeneralFastElementsKind( |
| 247 | ElementsKind elements_kind, |
| 248 | bool allow_only_packed) { |
| 249 | return IsFastElementsKind(elements_kind) && |
| 250 | (elements_kind != TERMINAL_FAST_ELEMENTS_KIND && |
| 251 | (!allow_only_packed || elements_kind != FAST_ELEMENTS)); |
| 252 | } |
| 253 | |
| 254 | |
| 255 | } } // namespace v8::internal |
| 256 | |
| 257 | #endif // V8_ELEMENTS_KIND_H_ |