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_OBJECTS_H_ 6 #define V8_OBJECTS_H_ 7 8 #include "src/allocation.h" 9 #include "src/assert-scope.h" 10 #include "src/builtins.h" 11 #include "src/elements-kind.h" 12 #include "src/field-index.h" 13 #include "src/flags.h" 14 #include "src/list.h" 15 #include "src/property-details.h" 16 #include "src/smart-pointers.h" 17 #include "src/unicode-inl.h" 18 #if V8_TARGET_ARCH_ARM64 19 #include "src/arm64/constants-arm64.h" 20 #elif V8_TARGET_ARCH_ARM 21 #include "src/arm/constants-arm.h" 22 #elif V8_TARGET_ARCH_MIPS 23 #include "src/mips/constants-mips.h" 24 #endif 25 #include "src/v8checks.h" 26 #include "src/zone.h" 27 28 29 // 30 // Most object types in the V8 JavaScript are described in this file. 31 // 32 // Inheritance hierarchy: 33 // - Object 34 // - Smi (immediate small integer) 35 // - HeapObject (superclass for everything allocated in the heap) 36 // - JSReceiver (suitable for property access) 37 // - JSObject 38 // - JSArray 39 // - JSArrayBuffer 40 // - JSArrayBufferView 41 // - JSTypedArray 42 // - JSDataView 43 // - JSSet 44 // - JSMap 45 // - JSSetIterator 46 // - JSMapIterator 47 // - JSWeakCollection 48 // - JSWeakMap 49 // - JSWeakSet 50 // - JSRegExp 51 // - JSFunction 52 // - JSGeneratorObject 53 // - JSModule 54 // - GlobalObject 55 // - JSGlobalObject 56 // - JSBuiltinsObject 57 // - JSGlobalProxy 58 // - JSValue 59 // - JSDate 60 // - JSMessageObject 61 // - JSProxy 62 // - JSFunctionProxy 63 // - FixedArrayBase 64 // - ByteArray 65 // - FixedArray 66 // - DescriptorArray 67 // - HashTable 68 // - Dictionary 69 // - StringTable 70 // - CompilationCacheTable 71 // - CodeCacheHashTable 72 // - MapCache 73 // - OrderedHashTable 74 // - OrderedHashSet 75 // - OrderedHashMap 76 // - Context 77 // - JSFunctionResultCache 78 // - ScopeInfo 79 // - TransitionArray 80 // - FixedDoubleArray 81 // - ExternalArray 82 // - ExternalUint8ClampedArray 83 // - ExternalInt8Array 84 // - ExternalUint8Array 85 // - ExternalInt16Array 86 // - ExternalUint16Array 87 // - ExternalInt32Array 88 // - ExternalUint32Array 89 // - ExternalFloat32Array 90 // - Name 91 // - String 92 // - SeqString 93 // - SeqOneByteString 94 // - SeqTwoByteString 95 // - SlicedString 96 // - ConsString 97 // - ExternalString 98 // - ExternalAsciiString 99 // - ExternalTwoByteString 100 // - InternalizedString 101 // - SeqInternalizedString 102 // - SeqOneByteInternalizedString 103 // - SeqTwoByteInternalizedString 104 // - ConsInternalizedString 105 // - ExternalInternalizedString 106 // - ExternalAsciiInternalizedString 107 // - ExternalTwoByteInternalizedString 108 // - Symbol 109 // - HeapNumber 110 // - Cell 111 // - PropertyCell 112 // - Code 113 // - Map 114 // - Oddball 115 // - Foreign 116 // - SharedFunctionInfo 117 // - Struct 118 // - Box 119 // - DeclaredAccessorDescriptor 120 // - AccessorInfo 121 // - DeclaredAccessorInfo 122 // - ExecutableAccessorInfo 123 // - AccessorPair 124 // - AccessCheckInfo 125 // - InterceptorInfo 126 // - CallHandlerInfo 127 // - TemplateInfo 128 // - FunctionTemplateInfo 129 // - ObjectTemplateInfo 130 // - Script 131 // - SignatureInfo 132 // - TypeSwitchInfo 133 // - DebugInfo 134 // - BreakPointInfo 135 // - CodeCache 136 // 137 // Formats of Object*: 138 // Smi: [31 bit signed int] 0 139 // HeapObject: [32 bit direct pointer] (4 byte aligned) | 01 140 141 namespace v8 { 142 namespace internal { 143 144 enum KeyedAccessStoreMode { 145 STANDARD_STORE, 146 STORE_TRANSITION_SMI_TO_OBJECT, 147 STORE_TRANSITION_SMI_TO_DOUBLE, 148 STORE_TRANSITION_DOUBLE_TO_OBJECT, 149 STORE_TRANSITION_HOLEY_SMI_TO_OBJECT, 150 STORE_TRANSITION_HOLEY_SMI_TO_DOUBLE, 151 STORE_TRANSITION_HOLEY_DOUBLE_TO_OBJECT, 152 STORE_AND_GROW_NO_TRANSITION, 153 STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT, 154 STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE, 155 STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT, 156 STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_OBJECT, 157 STORE_AND_GROW_TRANSITION_HOLEY_SMI_TO_DOUBLE, 158 STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT, 159 STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS, 160 STORE_NO_TRANSITION_HANDLE_COW 161 }; 162 163 164 enum ContextualMode { 165 NOT_CONTEXTUAL, 166 CONTEXTUAL 167 }; 168 169 170 static const int kGrowICDelta = STORE_AND_GROW_NO_TRANSITION - 171 STANDARD_STORE; 172 STATIC_ASSERT(STANDARD_STORE == 0); 173 STATIC_ASSERT(kGrowICDelta == 174 STORE_AND_GROW_TRANSITION_SMI_TO_OBJECT - 175 STORE_TRANSITION_SMI_TO_OBJECT); 176 STATIC_ASSERT(kGrowICDelta == 177 STORE_AND_GROW_TRANSITION_SMI_TO_DOUBLE - 178 STORE_TRANSITION_SMI_TO_DOUBLE); 179 STATIC_ASSERT(kGrowICDelta == 180 STORE_AND_GROW_TRANSITION_DOUBLE_TO_OBJECT - 181 STORE_TRANSITION_DOUBLE_TO_OBJECT); 182 183 184 static inline KeyedAccessStoreMode GetGrowStoreMode( 185 KeyedAccessStoreMode store_mode) { 186 if (store_mode < STORE_AND_GROW_NO_TRANSITION) { 187 store_mode = static_cast<KeyedAccessStoreMode>( 188 static_cast<int>(store_mode) + kGrowICDelta); 189 } 190 return store_mode; 191 } 192 193 194 static inline bool IsTransitionStoreMode(KeyedAccessStoreMode store_mode) { 195 return store_mode > STANDARD_STORE && 196 store_mode <= STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT && 197 store_mode != STORE_AND_GROW_NO_TRANSITION; 198 } 199 200 201 static inline KeyedAccessStoreMode GetNonTransitioningStoreMode( 202 KeyedAccessStoreMode store_mode) { 203 if (store_mode >= STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS) { 204 return store_mode; 205 } 206 if (store_mode >= STORE_AND_GROW_NO_TRANSITION) { 207 return STORE_AND_GROW_NO_TRANSITION; 208 } 209 return STANDARD_STORE; 210 } 211 212 213 static inline bool IsGrowStoreMode(KeyedAccessStoreMode store_mode) { 214 return store_mode >= STORE_AND_GROW_NO_TRANSITION && 215 store_mode <= STORE_AND_GROW_TRANSITION_HOLEY_DOUBLE_TO_OBJECT; 216 } 217 218 219 // Setter that skips the write barrier if mode is SKIP_WRITE_BARRIER. 220 enum WriteBarrierMode { SKIP_WRITE_BARRIER, UPDATE_WRITE_BARRIER }; 221 222 223 // Indicates whether a value can be loaded as a constant. 224 enum StoreMode { 225 ALLOW_AS_CONSTANT, 226 FORCE_FIELD 227 }; 228 229 230 // PropertyNormalizationMode is used to specify whether to keep 231 // inobject properties when normalizing properties of a JSObject. 232 enum PropertyNormalizationMode { 233 CLEAR_INOBJECT_PROPERTIES, 234 KEEP_INOBJECT_PROPERTIES 235 }; 236 237 238 // NormalizedMapSharingMode is used to specify whether a map may be shared 239 // by different objects with normalized properties. 240 enum NormalizedMapSharingMode { 241 UNIQUE_NORMALIZED_MAP, 242 SHARED_NORMALIZED_MAP 243 }; 244 245 246 // Indicates whether transitions can be added to a source map or not. 247 enum TransitionFlag { 248 INSERT_TRANSITION, 249 OMIT_TRANSITION 250 }; 251 252 253 enum DebugExtraICState { 254 DEBUG_BREAK, 255 DEBUG_PREPARE_STEP_IN 256 }; 257 258 259 // Indicates whether the transition is simple: the target map of the transition 260 // either extends the current map with a new property, or it modifies the 261 // property that was added last to the current map. 262 enum SimpleTransitionFlag { 263 SIMPLE_TRANSITION, 264 FULL_TRANSITION 265 }; 266 267 268 // Indicates whether we are only interested in the descriptors of a particular 269 // map, or in all descriptors in the descriptor array. 270 enum DescriptorFlag { 271 ALL_DESCRIPTORS, 272 OWN_DESCRIPTORS 273 }; 274 275 // The GC maintains a bit of information, the MarkingParity, which toggles 276 // from odd to even and back every time marking is completed. Incremental 277 // marking can visit an object twice during a marking phase, so algorithms that 278 // that piggy-back on marking can use the parity to ensure that they only 279 // perform an operation on an object once per marking phase: they record the 280 // MarkingParity when they visit an object, and only re-visit the object when it 281 // is marked again and the MarkingParity changes. 282 enum MarkingParity { 283 NO_MARKING_PARITY, 284 ODD_MARKING_PARITY, 285 EVEN_MARKING_PARITY 286 }; 287 288 // ICs store extra state in a Code object. The default extra state is 289 // kNoExtraICState. 290 typedef int ExtraICState; 291 static const ExtraICState kNoExtraICState = 0; 292 293 // Instance size sentinel for objects of variable size. 294 const int kVariableSizeSentinel = 0; 295 296 const int kStubMajorKeyBits = 7; 297 const int kStubMinorKeyBits = kBitsPerInt - kSmiTagSize - kStubMajorKeyBits; 298 299 // All Maps have a field instance_type containing a InstanceType. 300 // It describes the type of the instances. 301 // 302 // As an example, a JavaScript object is a heap object and its map 303 // instance_type is JS_OBJECT_TYPE. 304 // 305 // The names of the string instance types are intended to systematically 306 // mirror their encoding in the instance_type field of the map. The default 307 // encoding is considered TWO_BYTE. It is not mentioned in the name. ASCII 308 // encoding is mentioned explicitly in the name. Likewise, the default 309 // representation is considered sequential. It is not mentioned in the 310 // name. The other representations (e.g. CONS, EXTERNAL) are explicitly 311 // mentioned. Finally, the string is either a STRING_TYPE (if it is a normal 312 // string) or a INTERNALIZED_STRING_TYPE (if it is a internalized string). 313 // 314 // NOTE: The following things are some that depend on the string types having 315 // instance_types that are less than those of all other types: 316 // HeapObject::Size, HeapObject::IterateBody, the typeof operator, and 317 // Object::IsString. 318 // 319 // NOTE: Everything following JS_VALUE_TYPE is considered a 320 // JSObject for GC purposes. The first four entries here have typeof 321 // 'object', whereas JS_FUNCTION_TYPE has typeof 'function'. 322 #define INSTANCE_TYPE_LIST(V) \ 323 V(STRING_TYPE) \ 324 V(ASCII_STRING_TYPE) \ 325 V(CONS_STRING_TYPE) \ 326 V(CONS_ASCII_STRING_TYPE) \ 327 V(SLICED_STRING_TYPE) \ 328 V(SLICED_ASCII_STRING_TYPE) \ 329 V(EXTERNAL_STRING_TYPE) \ 330 V(EXTERNAL_ASCII_STRING_TYPE) \ 331 V(EXTERNAL_STRING_WITH_ONE_BYTE_DATA_TYPE) \ 332 V(SHORT_EXTERNAL_STRING_TYPE) \ 333 V(SHORT_EXTERNAL_ASCII_STRING_TYPE) \ 334 V(SHORT_EXTERNAL_STRING_WITH_ONE_BYTE_DATA_TYPE) \ 335 \ 336 V(INTERNALIZED_STRING_TYPE) \ 337 V(ASCII_INTERNALIZED_STRING_TYPE) \ 338 V(EXTERNAL_INTERNALIZED_STRING_TYPE) \ 339 V(EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE) \ 340 V(EXTERNAL_INTERNALIZED_STRING_WITH_ONE_BYTE_DATA_TYPE) \ 341 V(SHORT_EXTERNAL_INTERNALIZED_STRING_TYPE) \ 342 V(SHORT_EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE) \ 343 V(SHORT_EXTERNAL_INTERNALIZED_STRING_WITH_ONE_BYTE_DATA_TYPE) \ 344 \ 345 V(SYMBOL_TYPE) \ 346 \ 347 V(MAP_TYPE) \ 348 V(CODE_TYPE) \ 349 V(ODDBALL_TYPE) \ 350 V(CELL_TYPE) \ 351 V(PROPERTY_CELL_TYPE) \ 352 \ 353 V(HEAP_NUMBER_TYPE) \ 354 V(FOREIGN_TYPE) \ 355 V(BYTE_ARRAY_TYPE) \ 356 V(FREE_SPACE_TYPE) \ 357 /* Note: the order of these external array */ \ 358 /* types is relied upon in */ \ 359 /* Object::IsExternalArray(). */ \ 360 V(EXTERNAL_INT8_ARRAY_TYPE) \ 361 V(EXTERNAL_UINT8_ARRAY_TYPE) \ 362 V(EXTERNAL_INT16_ARRAY_TYPE) \ 363 V(EXTERNAL_UINT16_ARRAY_TYPE) \ 364 V(EXTERNAL_INT32_ARRAY_TYPE) \ 365 V(EXTERNAL_UINT32_ARRAY_TYPE) \ 366 V(EXTERNAL_FLOAT32_ARRAY_TYPE) \ 367 V(EXTERNAL_FLOAT64_ARRAY_TYPE) \ 368 V(EXTERNAL_UINT8_CLAMPED_ARRAY_TYPE) \ 369 \ 370 V(FIXED_INT8_ARRAY_TYPE) \ 371 V(FIXED_UINT8_ARRAY_TYPE) \ 372 V(FIXED_INT16_ARRAY_TYPE) \ 373 V(FIXED_UINT16_ARRAY_TYPE) \ 374 V(FIXED_INT32_ARRAY_TYPE) \ 375 V(FIXED_UINT32_ARRAY_TYPE) \ 376 V(FIXED_FLOAT32_ARRAY_TYPE) \ 377 V(FIXED_FLOAT64_ARRAY_TYPE) \ 378 V(FIXED_UINT8_CLAMPED_ARRAY_TYPE) \ 379 \ 380 V(FILLER_TYPE) \ 381 \ 382 V(DECLARED_ACCESSOR_DESCRIPTOR_TYPE) \ 383 V(DECLARED_ACCESSOR_INFO_TYPE) \ 384 V(EXECUTABLE_ACCESSOR_INFO_TYPE) \ 385 V(ACCESSOR_PAIR_TYPE) \ 386 V(ACCESS_CHECK_INFO_TYPE) \ 387 V(INTERCEPTOR_INFO_TYPE) \ 388 V(CALL_HANDLER_INFO_TYPE) \ 389 V(FUNCTION_TEMPLATE_INFO_TYPE) \ 390 V(OBJECT_TEMPLATE_INFO_TYPE) \ 391 V(SIGNATURE_INFO_TYPE) \ 392 V(TYPE_SWITCH_INFO_TYPE) \ 393 V(ALLOCATION_MEMENTO_TYPE) \ 394 V(ALLOCATION_SITE_TYPE) \ 395 V(SCRIPT_TYPE) \ 396 V(CODE_CACHE_TYPE) \ 397 V(POLYMORPHIC_CODE_CACHE_TYPE) \ 398 V(TYPE_FEEDBACK_INFO_TYPE) \ 399 V(ALIASED_ARGUMENTS_ENTRY_TYPE) \ 400 V(BOX_TYPE) \ 401 \ 402 V(FIXED_ARRAY_TYPE) \ 403 V(FIXED_DOUBLE_ARRAY_TYPE) \ 404 V(CONSTANT_POOL_ARRAY_TYPE) \ 405 V(SHARED_FUNCTION_INFO_TYPE) \ 406 \ 407 V(JS_MESSAGE_OBJECT_TYPE) \ 408 \ 409 V(JS_VALUE_TYPE) \ 410 V(JS_DATE_TYPE) \ 411 V(JS_OBJECT_TYPE) \ 412 V(JS_CONTEXT_EXTENSION_OBJECT_TYPE) \ 413 V(JS_GENERATOR_OBJECT_TYPE) \ 414 V(JS_MODULE_TYPE) \ 415 V(JS_GLOBAL_OBJECT_TYPE) \ 416 V(JS_BUILTINS_OBJECT_TYPE) \ 417 V(JS_GLOBAL_PROXY_TYPE) \ 418 V(JS_ARRAY_TYPE) \ 419 V(JS_ARRAY_BUFFER_TYPE) \ 420 V(JS_TYPED_ARRAY_TYPE) \ 421 V(JS_DATA_VIEW_TYPE) \ 422 V(JS_PROXY_TYPE) \ 423 V(JS_SET_TYPE) \ 424 V(JS_MAP_TYPE) \ 425 V(JS_SET_ITERATOR_TYPE) \ 426 V(JS_MAP_ITERATOR_TYPE) \ 427 V(JS_WEAK_MAP_TYPE) \ 428 V(JS_WEAK_SET_TYPE) \ 429 V(JS_REGEXP_TYPE) \ 430 \ 431 V(JS_FUNCTION_TYPE) \ 432 V(JS_FUNCTION_PROXY_TYPE) \ 433 V(DEBUG_INFO_TYPE) \ 434 V(BREAK_POINT_INFO_TYPE) 435 436 437 // Since string types are not consecutive, this macro is used to 438 // iterate over them. 439 #define STRING_TYPE_LIST(V) \ 440 V(STRING_TYPE, \ 441 kVariableSizeSentinel, \ 442 string, \ 443 String) \ 444 V(ASCII_STRING_TYPE, \ 445 kVariableSizeSentinel, \ 446 ascii_string, \ 447 AsciiString) \ 448 V(CONS_STRING_TYPE, \ 449 ConsString::kSize, \ 450 cons_string, \ 451 ConsString) \ 452 V(CONS_ASCII_STRING_TYPE, \ 453 ConsString::kSize, \ 454 cons_ascii_string, \ 455 ConsAsciiString) \ 456 V(SLICED_STRING_TYPE, \ 457 SlicedString::kSize, \ 458 sliced_string, \ 459 SlicedString) \ 460 V(SLICED_ASCII_STRING_TYPE, \ 461 SlicedString::kSize, \ 462 sliced_ascii_string, \ 463 SlicedAsciiString) \ 464 V(EXTERNAL_STRING_TYPE, \ 465 ExternalTwoByteString::kSize, \ 466 external_string, \ 467 ExternalString) \ 468 V(EXTERNAL_ASCII_STRING_TYPE, \ 469 ExternalAsciiString::kSize, \ 470 external_ascii_string, \ 471 ExternalAsciiString) \ 472 V(EXTERNAL_STRING_WITH_ONE_BYTE_DATA_TYPE, \ 473 ExternalTwoByteString::kSize, \ 474 external_string_with_one_byte_data, \ 475 ExternalStringWithOneByteData) \ 476 V(SHORT_EXTERNAL_STRING_TYPE, \ 477 ExternalTwoByteString::kShortSize, \ 478 short_external_string, \ 479 ShortExternalString) \ 480 V(SHORT_EXTERNAL_ASCII_STRING_TYPE, \ 481 ExternalAsciiString::kShortSize, \ 482 short_external_ascii_string, \ 483 ShortExternalAsciiString) \ 484 V(SHORT_EXTERNAL_STRING_WITH_ONE_BYTE_DATA_TYPE, \ 485 ExternalTwoByteString::kShortSize, \ 486 short_external_string_with_one_byte_data, \ 487 ShortExternalStringWithOneByteData) \ 488 \ 489 V(INTERNALIZED_STRING_TYPE, \ 490 kVariableSizeSentinel, \ 491 internalized_string, \ 492 InternalizedString) \ 493 V(ASCII_INTERNALIZED_STRING_TYPE, \ 494 kVariableSizeSentinel, \ 495 ascii_internalized_string, \ 496 AsciiInternalizedString) \ 497 V(EXTERNAL_INTERNALIZED_STRING_TYPE, \ 498 ExternalTwoByteString::kSize, \ 499 external_internalized_string, \ 500 ExternalInternalizedString) \ 501 V(EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE, \ 502 ExternalAsciiString::kSize, \ 503 external_ascii_internalized_string, \ 504 ExternalAsciiInternalizedString) \ 505 V(EXTERNAL_INTERNALIZED_STRING_WITH_ONE_BYTE_DATA_TYPE, \ 506 ExternalTwoByteString::kSize, \ 507 external_internalized_string_with_one_byte_data, \ 508 ExternalInternalizedStringWithOneByteData) \ 509 V(SHORT_EXTERNAL_INTERNALIZED_STRING_TYPE, \ 510 ExternalTwoByteString::kShortSize, \ 511 short_external_internalized_string, \ 512 ShortExternalInternalizedString) \ 513 V(SHORT_EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE, \ 514 ExternalAsciiString::kShortSize, \ 515 short_external_ascii_internalized_string, \ 516 ShortExternalAsciiInternalizedString) \ 517 V(SHORT_EXTERNAL_INTERNALIZED_STRING_WITH_ONE_BYTE_DATA_TYPE, \ 518 ExternalTwoByteString::kShortSize, \ 519 short_external_internalized_string_with_one_byte_data, \ 520 ShortExternalInternalizedStringWithOneByteData) \ 521 522 // A struct is a simple object a set of object-valued fields. Including an 523 // object type in this causes the compiler to generate most of the boilerplate 524 // code for the class including allocation and garbage collection routines, 525 // casts and predicates. All you need to define is the class, methods and 526 // object verification routines. Easy, no? 527 // 528 // Note that for subtle reasons related to the ordering or numerical values of 529 // type tags, elements in this list have to be added to the INSTANCE_TYPE_LIST 530 // manually. 531 #define STRUCT_LIST(V) \ 532 V(BOX, Box, box) \ 533 V(DECLARED_ACCESSOR_DESCRIPTOR, \ 534 DeclaredAccessorDescriptor, \ 535 declared_accessor_descriptor) \ 536 V(DECLARED_ACCESSOR_INFO, DeclaredAccessorInfo, declared_accessor_info) \ 537 V(EXECUTABLE_ACCESSOR_INFO, ExecutableAccessorInfo, executable_accessor_info)\ 538 V(ACCESSOR_PAIR, AccessorPair, accessor_pair) \ 539 V(ACCESS_CHECK_INFO, AccessCheckInfo, access_check_info) \ 540 V(INTERCEPTOR_INFO, InterceptorInfo, interceptor_info) \ 541 V(CALL_HANDLER_INFO, CallHandlerInfo, call_handler_info) \ 542 V(FUNCTION_TEMPLATE_INFO, FunctionTemplateInfo, function_template_info) \ 543 V(OBJECT_TEMPLATE_INFO, ObjectTemplateInfo, object_template_info) \ 544 V(SIGNATURE_INFO, SignatureInfo, signature_info) \ 545 V(TYPE_SWITCH_INFO, TypeSwitchInfo, type_switch_info) \ 546 V(SCRIPT, Script, script) \ 547 V(ALLOCATION_SITE, AllocationSite, allocation_site) \ 548 V(ALLOCATION_MEMENTO, AllocationMemento, allocation_memento) \ 549 V(CODE_CACHE, CodeCache, code_cache) \ 550 V(POLYMORPHIC_CODE_CACHE, PolymorphicCodeCache, polymorphic_code_cache) \ 551 V(TYPE_FEEDBACK_INFO, TypeFeedbackInfo, type_feedback_info) \ 552 V(ALIASED_ARGUMENTS_ENTRY, AliasedArgumentsEntry, aliased_arguments_entry) \ 553 V(DEBUG_INFO, DebugInfo, debug_info) \ 554 V(BREAK_POINT_INFO, BreakPointInfo, break_point_info) 555 556 // We use the full 8 bits of the instance_type field to encode heap object 557 // instance types. The high-order bit (bit 7) is set if the object is not a 558 // string, and cleared if it is a string. 559 const uint32_t kIsNotStringMask = 0x80; 560 const uint32_t kStringTag = 0x0; 561 const uint32_t kNotStringTag = 0x80; 562 563 // Bit 6 indicates that the object is an internalized string (if set) or not. 564 // Bit 7 has to be clear as well. 565 const uint32_t kIsNotInternalizedMask = 0x40; 566 const uint32_t kNotInternalizedTag = 0x40; 567 const uint32_t kInternalizedTag = 0x0; 568 569 // If bit 7 is clear then bit 2 indicates whether the string consists of 570 // two-byte characters or one-byte characters. 571 const uint32_t kStringEncodingMask = 0x4; 572 const uint32_t kTwoByteStringTag = 0x0; 573 const uint32_t kOneByteStringTag = 0x4; 574 575 // If bit 7 is clear, the low-order 2 bits indicate the representation 576 // of the string. 577 const uint32_t kStringRepresentationMask = 0x03; 578 enum StringRepresentationTag { 579 kSeqStringTag = 0x0, 580 kConsStringTag = 0x1, 581 kExternalStringTag = 0x2, 582 kSlicedStringTag = 0x3 583 }; 584 const uint32_t kIsIndirectStringMask = 0x1; 585 const uint32_t kIsIndirectStringTag = 0x1; 586 STATIC_ASSERT((kSeqStringTag & kIsIndirectStringMask) == 0); // NOLINT 587 STATIC_ASSERT((kExternalStringTag & kIsIndirectStringMask) == 0); // NOLINT 588 STATIC_ASSERT((kConsStringTag & 589 kIsIndirectStringMask) == kIsIndirectStringTag); // NOLINT 590 STATIC_ASSERT((kSlicedStringTag & 591 kIsIndirectStringMask) == kIsIndirectStringTag); // NOLINT 592 593 // Use this mask to distinguish between cons and slice only after making 594 // sure that the string is one of the two (an indirect string). 595 const uint32_t kSlicedNotConsMask = kSlicedStringTag & ~kConsStringTag; 596 STATIC_ASSERT(IS_POWER_OF_TWO(kSlicedNotConsMask)); 597 598 // If bit 7 is clear, then bit 3 indicates whether this two-byte 599 // string actually contains one byte data. 600 const uint32_t kOneByteDataHintMask = 0x08; 601 const uint32_t kOneByteDataHintTag = 0x08; 602 603 // If bit 7 is clear and string representation indicates an external string, 604 // then bit 4 indicates whether the data pointer is cached. 605 const uint32_t kShortExternalStringMask = 0x10; 606 const uint32_t kShortExternalStringTag = 0x10; 607 608 609 // A ConsString with an empty string as the right side is a candidate 610 // for being shortcut by the garbage collector unless it is internalized. 611 // It's not common to have non-flat internalized strings, so we do not 612 // shortcut them thereby avoiding turning internalized strings into strings. 613 // See heap.cc and mark-compact.cc. 614 const uint32_t kShortcutTypeMask = 615 kIsNotStringMask | 616 kIsNotInternalizedMask | 617 kStringRepresentationMask; 618 const uint32_t kShortcutTypeTag = kConsStringTag | kNotInternalizedTag; 619 620 621 enum InstanceType { 622 // String types. 623 INTERNALIZED_STRING_TYPE = kTwoByteStringTag | kSeqStringTag 624 | kInternalizedTag, 625 ASCII_INTERNALIZED_STRING_TYPE = kOneByteStringTag | kSeqStringTag 626 | kInternalizedTag, 627 EXTERNAL_INTERNALIZED_STRING_TYPE = kTwoByteStringTag | kExternalStringTag 628 | kInternalizedTag, 629 EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE = kOneByteStringTag 630 | kExternalStringTag | kInternalizedTag, 631 EXTERNAL_INTERNALIZED_STRING_WITH_ONE_BYTE_DATA_TYPE = 632 EXTERNAL_INTERNALIZED_STRING_TYPE | kOneByteDataHintTag 633 | kInternalizedTag, 634 SHORT_EXTERNAL_INTERNALIZED_STRING_TYPE = 635 EXTERNAL_INTERNALIZED_STRING_TYPE | kShortExternalStringTag 636 | kInternalizedTag, 637 SHORT_EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE = 638 EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE | kShortExternalStringTag 639 | kInternalizedTag, 640 SHORT_EXTERNAL_INTERNALIZED_STRING_WITH_ONE_BYTE_DATA_TYPE = 641 EXTERNAL_INTERNALIZED_STRING_WITH_ONE_BYTE_DATA_TYPE 642 | kShortExternalStringTag | kInternalizedTag, 643 644 STRING_TYPE = INTERNALIZED_STRING_TYPE | kNotInternalizedTag, 645 ASCII_STRING_TYPE = ASCII_INTERNALIZED_STRING_TYPE | kNotInternalizedTag, 646 CONS_STRING_TYPE = kTwoByteStringTag | kConsStringTag | kNotInternalizedTag, 647 CONS_ASCII_STRING_TYPE = 648 kOneByteStringTag | kConsStringTag | kNotInternalizedTag, 649 650 SLICED_STRING_TYPE = 651 kTwoByteStringTag | kSlicedStringTag | kNotInternalizedTag, 652 SLICED_ASCII_STRING_TYPE = 653 kOneByteStringTag | kSlicedStringTag | kNotInternalizedTag, 654 EXTERNAL_STRING_TYPE = 655 EXTERNAL_INTERNALIZED_STRING_TYPE | kNotInternalizedTag, 656 EXTERNAL_ASCII_STRING_TYPE = 657 EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE | kNotInternalizedTag, 658 EXTERNAL_STRING_WITH_ONE_BYTE_DATA_TYPE = 659 EXTERNAL_INTERNALIZED_STRING_WITH_ONE_BYTE_DATA_TYPE 660 | kNotInternalizedTag, 661 SHORT_EXTERNAL_STRING_TYPE = 662 SHORT_EXTERNAL_INTERNALIZED_STRING_TYPE | kNotInternalizedTag, 663 SHORT_EXTERNAL_ASCII_STRING_TYPE = 664 SHORT_EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE | kNotInternalizedTag, 665 SHORT_EXTERNAL_STRING_WITH_ONE_BYTE_DATA_TYPE = 666 SHORT_EXTERNAL_INTERNALIZED_STRING_WITH_ONE_BYTE_DATA_TYPE 667 | kNotInternalizedTag, 668 669 // Non-string names 670 SYMBOL_TYPE = kNotStringTag, // FIRST_NONSTRING_TYPE, LAST_NAME_TYPE 671 672 // Objects allocated in their own spaces (never in new space). 673 MAP_TYPE, 674 CODE_TYPE, 675 ODDBALL_TYPE, 676 CELL_TYPE, 677 PROPERTY_CELL_TYPE, 678 679 // "Data", objects that cannot contain non-map-word pointers to heap 680 // objects. 681 HEAP_NUMBER_TYPE, 682 FOREIGN_TYPE, 683 BYTE_ARRAY_TYPE, 684 FREE_SPACE_TYPE, 685 686 EXTERNAL_INT8_ARRAY_TYPE, // FIRST_EXTERNAL_ARRAY_TYPE 687 EXTERNAL_UINT8_ARRAY_TYPE, 688 EXTERNAL_INT16_ARRAY_TYPE, 689 EXTERNAL_UINT16_ARRAY_TYPE, 690 EXTERNAL_INT32_ARRAY_TYPE, 691 EXTERNAL_UINT32_ARRAY_TYPE, 692 EXTERNAL_FLOAT32_ARRAY_TYPE, 693 EXTERNAL_FLOAT64_ARRAY_TYPE, 694 EXTERNAL_UINT8_CLAMPED_ARRAY_TYPE, // LAST_EXTERNAL_ARRAY_TYPE 695 696 FIXED_INT8_ARRAY_TYPE, // FIRST_FIXED_TYPED_ARRAY_TYPE 697 FIXED_UINT8_ARRAY_TYPE, 698 FIXED_INT16_ARRAY_TYPE, 699 FIXED_UINT16_ARRAY_TYPE, 700 FIXED_INT32_ARRAY_TYPE, 701 FIXED_UINT32_ARRAY_TYPE, 702 FIXED_FLOAT32_ARRAY_TYPE, 703 FIXED_FLOAT64_ARRAY_TYPE, 704 FIXED_UINT8_CLAMPED_ARRAY_TYPE, // LAST_FIXED_TYPED_ARRAY_TYPE 705 706 FIXED_DOUBLE_ARRAY_TYPE, 707 FILLER_TYPE, // LAST_DATA_TYPE 708 709 // Structs. 710 DECLARED_ACCESSOR_DESCRIPTOR_TYPE, 711 DECLARED_ACCESSOR_INFO_TYPE, 712 EXECUTABLE_ACCESSOR_INFO_TYPE, 713 ACCESSOR_PAIR_TYPE, 714 ACCESS_CHECK_INFO_TYPE, 715 INTERCEPTOR_INFO_TYPE, 716 CALL_HANDLER_INFO_TYPE, 717 FUNCTION_TEMPLATE_INFO_TYPE, 718 OBJECT_TEMPLATE_INFO_TYPE, 719 SIGNATURE_INFO_TYPE, 720 TYPE_SWITCH_INFO_TYPE, 721 ALLOCATION_SITE_TYPE, 722 ALLOCATION_MEMENTO_TYPE, 723 SCRIPT_TYPE, 724 CODE_CACHE_TYPE, 725 POLYMORPHIC_CODE_CACHE_TYPE, 726 TYPE_FEEDBACK_INFO_TYPE, 727 ALIASED_ARGUMENTS_ENTRY_TYPE, 728 BOX_TYPE, 729 DEBUG_INFO_TYPE, 730 BREAK_POINT_INFO_TYPE, 731 732 FIXED_ARRAY_TYPE, 733 CONSTANT_POOL_ARRAY_TYPE, 734 SHARED_FUNCTION_INFO_TYPE, 735 736 // All the following types are subtypes of JSReceiver, which corresponds to 737 // objects in the JS sense. The first and the last type in this range are 738 // the two forms of function. This organization enables using the same 739 // compares for checking the JS_RECEIVER/SPEC_OBJECT range and the 740 // NONCALLABLE_JS_OBJECT range. 741 JS_FUNCTION_PROXY_TYPE, // FIRST_JS_RECEIVER_TYPE, FIRST_JS_PROXY_TYPE 742 JS_PROXY_TYPE, // LAST_JS_PROXY_TYPE 743 744 JS_VALUE_TYPE, // FIRST_JS_OBJECT_TYPE 745 JS_MESSAGE_OBJECT_TYPE, 746 JS_DATE_TYPE, 747 JS_OBJECT_TYPE, 748 JS_CONTEXT_EXTENSION_OBJECT_TYPE, 749 JS_GENERATOR_OBJECT_TYPE, 750 JS_MODULE_TYPE, 751 JS_GLOBAL_OBJECT_TYPE, 752 JS_BUILTINS_OBJECT_TYPE, 753 JS_GLOBAL_PROXY_TYPE, 754 JS_ARRAY_TYPE, 755 JS_ARRAY_BUFFER_TYPE, 756 JS_TYPED_ARRAY_TYPE, 757 JS_DATA_VIEW_TYPE, 758 JS_SET_TYPE, 759 JS_MAP_TYPE, 760 JS_SET_ITERATOR_TYPE, 761 JS_MAP_ITERATOR_TYPE, 762 JS_WEAK_MAP_TYPE, 763 JS_WEAK_SET_TYPE, 764 765 JS_REGEXP_TYPE, 766 767 JS_FUNCTION_TYPE, // LAST_JS_OBJECT_TYPE, LAST_JS_RECEIVER_TYPE 768 769 // Pseudo-types 770 FIRST_TYPE = 0x0, 771 LAST_TYPE = JS_FUNCTION_TYPE, 772 FIRST_NAME_TYPE = FIRST_TYPE, 773 LAST_NAME_TYPE = SYMBOL_TYPE, 774 FIRST_UNIQUE_NAME_TYPE = INTERNALIZED_STRING_TYPE, 775 LAST_UNIQUE_NAME_TYPE = SYMBOL_TYPE, 776 FIRST_NONSTRING_TYPE = SYMBOL_TYPE, 777 // Boundaries for testing for an external array. 778 FIRST_EXTERNAL_ARRAY_TYPE = EXTERNAL_INT8_ARRAY_TYPE, 779 LAST_EXTERNAL_ARRAY_TYPE = EXTERNAL_UINT8_CLAMPED_ARRAY_TYPE, 780 // Boundaries for testing for a fixed typed array. 781 FIRST_FIXED_TYPED_ARRAY_TYPE = FIXED_INT8_ARRAY_TYPE, 782 LAST_FIXED_TYPED_ARRAY_TYPE = FIXED_UINT8_CLAMPED_ARRAY_TYPE, 783 // Boundary for promotion to old data space/old pointer space. 784 LAST_DATA_TYPE = FILLER_TYPE, 785 // Boundary for objects represented as JSReceiver (i.e. JSObject or JSProxy). 786 // Note that there is no range for JSObject or JSProxy, since their subtypes 787 // are not continuous in this enum! The enum ranges instead reflect the 788 // external class names, where proxies are treated as either ordinary objects, 789 // or functions. 790 FIRST_JS_RECEIVER_TYPE = JS_FUNCTION_PROXY_TYPE, 791 LAST_JS_RECEIVER_TYPE = LAST_TYPE, 792 // Boundaries for testing the types represented as JSObject 793 FIRST_JS_OBJECT_TYPE = JS_VALUE_TYPE, 794 LAST_JS_OBJECT_TYPE = LAST_TYPE, 795 // Boundaries for testing the types represented as JSProxy 796 FIRST_JS_PROXY_TYPE = JS_FUNCTION_PROXY_TYPE, 797 LAST_JS_PROXY_TYPE = JS_PROXY_TYPE, 798 // Boundaries for testing whether the type is a JavaScript object. 799 FIRST_SPEC_OBJECT_TYPE = FIRST_JS_RECEIVER_TYPE, 800 LAST_SPEC_OBJECT_TYPE = LAST_JS_RECEIVER_TYPE, 801 // Boundaries for testing the types for which typeof is "object". 802 FIRST_NONCALLABLE_SPEC_OBJECT_TYPE = JS_PROXY_TYPE, 803 LAST_NONCALLABLE_SPEC_OBJECT_TYPE = JS_REGEXP_TYPE, 804 // Note that the types for which typeof is "function" are not continuous. 805 // Define this so that we can put assertions on discrete checks. 806 NUM_OF_CALLABLE_SPEC_OBJECT_TYPES = 2 807 }; 808 809 const int kExternalArrayTypeCount = 810 LAST_EXTERNAL_ARRAY_TYPE - FIRST_EXTERNAL_ARRAY_TYPE + 1; 811 812 STATIC_ASSERT(JS_OBJECT_TYPE == Internals::kJSObjectType); 813 STATIC_ASSERT(FIRST_NONSTRING_TYPE == Internals::kFirstNonstringType); 814 STATIC_ASSERT(ODDBALL_TYPE == Internals::kOddballType); 815 STATIC_ASSERT(FOREIGN_TYPE == Internals::kForeignType); 816 817 818 #define FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(V) \ 819 V(FAST_ELEMENTS_SUB_TYPE) \ 820 V(DICTIONARY_ELEMENTS_SUB_TYPE) \ 821 V(FAST_PROPERTIES_SUB_TYPE) \ 822 V(DICTIONARY_PROPERTIES_SUB_TYPE) \ 823 V(MAP_CODE_CACHE_SUB_TYPE) \ 824 V(SCOPE_INFO_SUB_TYPE) \ 825 V(STRING_TABLE_SUB_TYPE) \ 826 V(DESCRIPTOR_ARRAY_SUB_TYPE) \ 827 V(TRANSITION_ARRAY_SUB_TYPE) 828 829 enum FixedArraySubInstanceType { 830 #define DEFINE_FIXED_ARRAY_SUB_INSTANCE_TYPE(name) name, 831 FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(DEFINE_FIXED_ARRAY_SUB_INSTANCE_TYPE) 832 #undef DEFINE_FIXED_ARRAY_SUB_INSTANCE_TYPE 833 LAST_FIXED_ARRAY_SUB_TYPE = TRANSITION_ARRAY_SUB_TYPE 834 }; 835 836 837 enum CompareResult { 838 LESS = -1, 839 EQUAL = 0, 840 GREATER = 1, 841 842 NOT_EQUAL = GREATER 843 }; 844 845 846 #define DECL_BOOLEAN_ACCESSORS(name) \ 847 inline bool name(); \ 848 inline void set_##name(bool value); \ 849 850 851 #define DECL_ACCESSORS(name, type) \ 852 inline type* name(); \ 853 inline void set_##name(type* value, \ 854 WriteBarrierMode mode = UPDATE_WRITE_BARRIER); \ 855 856 class AccessorPair; 857 class AllocationSite; 858 class AllocationSiteCreationContext; 859 class AllocationSiteUsageContext; 860 class DictionaryElementsAccessor; 861 class ElementsAccessor; 862 class FixedArrayBase; 863 class GlobalObject; 864 class ObjectVisitor; 865 class LookupIterator; 866 class StringStream; 867 // We cannot just say "class HeapType;" if it is created from a template... =8-? 868 template<class> class TypeImpl; 869 struct HeapTypeConfig; 870 typedef TypeImpl<HeapTypeConfig> HeapType; 871 872 873 // A template-ized version of the IsXXX functions. 874 template <class C> inline bool Is(Object* obj); 875 876 #ifdef VERIFY_HEAP 877 #define DECLARE_VERIFIER(Name) void Name##Verify(); 878 #else 879 #define DECLARE_VERIFIER(Name) 880 #endif 881 882 #ifdef OBJECT_PRINT 883 #define DECLARE_PRINTER(Name) void Name##Print(FILE* out = stdout); 884 #else 885 #define DECLARE_PRINTER(Name) 886 #endif 887 888 889 #define OBJECT_TYPE_LIST(V) \ 890 V(Smi) \ 891 V(HeapObject) \ 892 V(Number) \ 893 894 #define HEAP_OBJECT_TYPE_LIST(V) \ 895 V(HeapNumber) \ 896 V(Name) \ 897 V(UniqueName) \ 898 V(String) \ 899 V(SeqString) \ 900 V(ExternalString) \ 901 V(ConsString) \ 902 V(SlicedString) \ 903 V(ExternalTwoByteString) \ 904 V(ExternalAsciiString) \ 905 V(SeqTwoByteString) \ 906 V(SeqOneByteString) \ 907 V(InternalizedString) \ 908 V(Symbol) \ 909 \ 910 V(ExternalArray) \ 911 V(ExternalInt8Array) \ 912 V(ExternalUint8Array) \ 913 V(ExternalInt16Array) \ 914 V(ExternalUint16Array) \ 915 V(ExternalInt32Array) \ 916 V(ExternalUint32Array) \ 917 V(ExternalFloat32Array) \ 918 V(ExternalFloat64Array) \ 919 V(ExternalUint8ClampedArray) \ 920 V(FixedTypedArrayBase) \ 921 V(FixedUint8Array) \ 922 V(FixedInt8Array) \ 923 V(FixedUint16Array) \ 924 V(FixedInt16Array) \ 925 V(FixedUint32Array) \ 926 V(FixedInt32Array) \ 927 V(FixedFloat32Array) \ 928 V(FixedFloat64Array) \ 929 V(FixedUint8ClampedArray) \ 930 V(ByteArray) \ 931 V(FreeSpace) \ 932 V(JSReceiver) \ 933 V(JSObject) \ 934 V(JSContextExtensionObject) \ 935 V(JSGeneratorObject) \ 936 V(JSModule) \ 937 V(Map) \ 938 V(DescriptorArray) \ 939 V(TransitionArray) \ 940 V(DeoptimizationInputData) \ 941 V(DeoptimizationOutputData) \ 942 V(DependentCode) \ 943 V(FixedArray) \ 944 V(FixedDoubleArray) \ 945 V(ConstantPoolArray) \ 946 V(Context) \ 947 V(NativeContext) \ 948 V(ScopeInfo) \ 949 V(JSFunction) \ 950 V(Code) \ 951 V(Oddball) \ 952 V(SharedFunctionInfo) \ 953 V(JSValue) \ 954 V(JSDate) \ 955 V(JSMessageObject) \ 956 V(StringWrapper) \ 957 V(Foreign) \ 958 V(Boolean) \ 959 V(JSArray) \ 960 V(JSArrayBuffer) \ 961 V(JSArrayBufferView) \ 962 V(JSTypedArray) \ 963 V(JSDataView) \ 964 V(JSProxy) \ 965 V(JSFunctionProxy) \ 966 V(JSSet) \ 967 V(JSMap) \ 968 V(JSSetIterator) \ 969 V(JSMapIterator) \ 970 V(JSWeakCollection) \ 971 V(JSWeakMap) \ 972 V(JSWeakSet) \ 973 V(JSRegExp) \ 974 V(HashTable) \ 975 V(Dictionary) \ 976 V(StringTable) \ 977 V(JSFunctionResultCache) \ 978 V(NormalizedMapCache) \ 979 V(CompilationCacheTable) \ 980 V(CodeCacheHashTable) \ 981 V(PolymorphicCodeCacheHashTable) \ 982 V(MapCache) \ 983 V(Primitive) \ 984 V(GlobalObject) \ 985 V(JSGlobalObject) \ 986 V(JSBuiltinsObject) \ 987 V(JSGlobalProxy) \ 988 V(UndetectableObject) \ 989 V(AccessCheckNeeded) \ 990 V(Cell) \ 991 V(PropertyCell) \ 992 V(ObjectHashTable) \ 993 V(WeakHashTable) \ 994 V(OrderedHashTable) 995 996 997 #define ERROR_MESSAGES_LIST(V) \ 998 V(kNoReason, "no reason") \ 999 \ 1000 V(k32BitValueInRegisterIsNotZeroExtended, \ 1001 "32 bit value in register is not zero-extended") \ 1002 V(kAlignmentMarkerExpected, "Alignment marker expected") \ 1003 V(kAllocationIsNotDoubleAligned, "Allocation is not double aligned") \ 1004 V(kAPICallReturnedInvalidObject, "API call returned invalid object") \ 1005 V(kArgumentsObjectValueInATestContext, \ 1006 "Arguments object value in a test context") \ 1007 V(kArrayBoilerplateCreationFailed, "Array boilerplate creation failed") \ 1008 V(kArrayIndexConstantValueTooBig, "Array index constant value too big") \ 1009 V(kAssignmentToArguments, "Assignment to arguments") \ 1010 V(kAssignmentToLetVariableBeforeInitialization, \ 1011 "Assignment to let variable before initialization") \ 1012 V(kAssignmentToLOOKUPVariable, "Assignment to LOOKUP variable") \ 1013 V(kAssignmentToParameterFunctionUsesArgumentsObject, \ 1014 "Assignment to parameter, function uses arguments object") \ 1015 V(kAssignmentToParameterInArgumentsObject, \ 1016 "Assignment to parameter in arguments object") \ 1017 V(kAttemptToUseUndefinedCache, "Attempt to use undefined cache") \ 1018 V(kBadValueContextForArgumentsObjectValue, \ 1019 "Bad value context for arguments object value") \ 1020 V(kBadValueContextForArgumentsValue, \ 1021 "Bad value context for arguments value") \ 1022 V(kBailedOutDueToDependencyChange, "Bailed out due to dependency change") \ 1023 V(kBailoutWasNotPrepared, "Bailout was not prepared") \ 1024 V(kBinaryStubGenerateFloatingPointCode, \ 1025 "BinaryStub_GenerateFloatingPointCode") \ 1026 V(kBothRegistersWereSmisInSelectNonSmi, \ 1027 "Both registers were smis in SelectNonSmi") \ 1028 V(kCallToAJavaScriptRuntimeFunction, \ 1029 "Call to a JavaScript runtime function") \ 1030 V(kCannotTranslatePositionInChangedArea, \ 1031 "Cannot translate position in changed area") \ 1032 V(kCodeGenerationFailed, "Code generation failed") \ 1033 V(kCodeObjectNotProperlyPatched, "Code object not properly patched") \ 1034 V(kCompoundAssignmentToLookupSlot, "Compound assignment to lookup slot") \ 1035 V(kContextAllocatedArguments, "Context-allocated arguments") \ 1036 V(kCopyBuffersOverlap, "Copy buffers overlap") \ 1037 V(kCouldNotGenerateZero, "Could not generate +0.0") \ 1038 V(kCouldNotGenerateNegativeZero, "Could not generate -0.0") \ 1039 V(kDebuggerHasBreakPoints, "Debugger has break points") \ 1040 V(kDebuggerStatement, "DebuggerStatement") \ 1041 V(kDeclarationInCatchContext, "Declaration in catch context") \ 1042 V(kDeclarationInWithContext, "Declaration in with context") \ 1043 V(kDefaultNaNModeNotSet, "Default NaN mode not set") \ 1044 V(kDeleteWithGlobalVariable, "Delete with global variable") \ 1045 V(kDeleteWithNonGlobalVariable, "Delete with non-global variable") \ 1046 V(kDestinationOfCopyNotAligned, "Destination of copy not aligned") \ 1047 V(kDontDeleteCellsCannotContainTheHole, \ 1048 "DontDelete cells can't contain the hole") \ 1049 V(kDoPushArgumentNotImplementedForDoubleType, \ 1050 "DoPushArgument not implemented for double type") \ 1051 V(kEliminatedBoundsCheckFailed, "Eliminated bounds check failed") \ 1052 V(kEmitLoadRegisterUnsupportedDoubleImmediate, \ 1053 "EmitLoadRegister: Unsupported double immediate") \ 1054 V(kEval, "eval") \ 1055 V(kExpected0AsASmiSentinel, "Expected 0 as a Smi sentinel") \ 1056 V(kExpectedAlignmentMarker, "Expected alignment marker") \ 1057 V(kExpectedAllocationSite, "Expected allocation site") \ 1058 V(kExpectedFunctionObject, "Expected function object in register") \ 1059 V(kExpectedHeapNumber, "Expected HeapNumber") \ 1060 V(kExpectedNativeContext, "Expected native context") \ 1061 V(kExpectedNonIdenticalObjects, "Expected non-identical objects") \ 1062 V(kExpectedNonNullContext, "Expected non-null context") \ 1063 V(kExpectedPositiveZero, "Expected +0.0") \ 1064 V(kExpectedAllocationSiteInCell, \ 1065 "Expected AllocationSite in property cell") \ 1066 V(kExpectedFixedArrayInFeedbackVector, \ 1067 "Expected fixed array in feedback vector") \ 1068 V(kExpectedFixedArrayInRegisterA2, \ 1069 "Expected fixed array in register a2") \ 1070 V(kExpectedFixedArrayInRegisterEbx, \ 1071 "Expected fixed array in register ebx") \ 1072 V(kExpectedFixedArrayInRegisterR2, \ 1073 "Expected fixed array in register r2") \ 1074 V(kExpectedFixedArrayInRegisterRbx, \ 1075 "Expected fixed array in register rbx") \ 1076 V(kExpectedNewSpaceObject, "Expected new space object") \ 1077 V(kExpectedSmiOrHeapNumber, "Expected smi or HeapNumber") \ 1078 V(kExpectedUndefinedOrCell, \ 1079 "Expected undefined or cell in register") \ 1080 V(kExpectingAlignmentForCopyBytes, \ 1081 "Expecting alignment for CopyBytes") \ 1082 V(kExportDeclaration, "Export declaration") \ 1083 V(kExternalStringExpectedButNotFound, \ 1084 "External string expected, but not found") \ 1085 V(kFailedBailedOutLastTime, "Failed/bailed out last time") \ 1086 V(kForInStatementIsNotFastCase, "ForInStatement is not fast case") \ 1087 V(kForInStatementOptimizationIsDisabled, \ 1088 "ForInStatement optimization is disabled") \ 1089 V(kForInStatementWithNonLocalEachVariable, \ 1090 "ForInStatement with non-local each variable") \ 1091 V(kForOfStatement, "ForOfStatement") \ 1092 V(kFrameIsExpectedToBeAligned, "Frame is expected to be aligned") \ 1093 V(kFunctionCallsEval, "Function calls eval") \ 1094 V(kFunctionIsAGenerator, "Function is a generator") \ 1095 V(kFunctionWithIllegalRedeclaration, "Function with illegal redeclaration") \ 1096 V(kGeneratedCodeIsTooLarge, "Generated code is too large") \ 1097 V(kGeneratorFailedToResume, "Generator failed to resume") \ 1098 V(kGenerator, "Generator") \ 1099 V(kGlobalFunctionsMustHaveInitialMap, \ 1100 "Global functions must have initial map") \ 1101 V(kHeapNumberMapRegisterClobbered, "HeapNumberMap register clobbered") \ 1102 V(kHydrogenFilter, "Optimization disabled by filter") \ 1103 V(kImportDeclaration, "Import declaration") \ 1104 V(kImproperObjectOnPrototypeChainForStore, \ 1105 "Improper object on prototype chain for store") \ 1106 V(kIndexIsNegative, "Index is negative") \ 1107 V(kIndexIsTooLarge, "Index is too large") \ 1108 V(kInlinedRuntimeFunctionClassOf, "Inlined runtime function: ClassOf") \ 1109 V(kInlinedRuntimeFunctionFastAsciiArrayJoin, \ 1110 "Inlined runtime function: FastAsciiArrayJoin") \ 1111 V(kInlinedRuntimeFunctionGeneratorNext, \ 1112 "Inlined runtime function: GeneratorNext") \ 1113 V(kInlinedRuntimeFunctionGeneratorThrow, \ 1114 "Inlined runtime function: GeneratorThrow") \ 1115 V(kInlinedRuntimeFunctionGetFromCache, \ 1116 "Inlined runtime function: GetFromCache") \ 1117 V(kInlinedRuntimeFunctionIsNonNegativeSmi, \ 1118 "Inlined runtime function: IsNonNegativeSmi") \ 1119 V(kInlinedRuntimeFunctionIsStringWrapperSafeForDefaultValueOf, \ 1120 "Inlined runtime function: IsStringWrapperSafeForDefaultValueOf") \ 1121 V(kInliningBailedOut, "Inlining bailed out") \ 1122 V(kInputGPRIsExpectedToHaveUpper32Cleared, \ 1123 "Input GPR is expected to have upper32 cleared") \ 1124 V(kInputStringTooLong, "Input string too long") \ 1125 V(kInstanceofStubUnexpectedCallSiteCacheCheck, \ 1126 "InstanceofStub unexpected call site cache (check)") \ 1127 V(kInstanceofStubUnexpectedCallSiteCacheCmp1, \ 1128 "InstanceofStub unexpected call site cache (cmp 1)") \ 1129 V(kInstanceofStubUnexpectedCallSiteCacheCmp2, \ 1130 "InstanceofStub unexpected call site cache (cmp 2)") \ 1131 V(kInstanceofStubUnexpectedCallSiteCacheMov, \ 1132 "InstanceofStub unexpected call site cache (mov)") \ 1133 V(kInteger32ToSmiFieldWritingToNonSmiLocation, \ 1134 "Integer32ToSmiField writing to non-smi location") \ 1135 V(kInvalidCaptureReferenced, "Invalid capture referenced") \ 1136 V(kInvalidElementsKindForInternalArrayOrInternalPackedArray, \ 1137 "Invalid ElementsKind for InternalArray or InternalPackedArray") \ 1138 V(kInvalidFullCodegenState, "invalid full-codegen state") \ 1139 V(kInvalidHandleScopeLevel, "Invalid HandleScope level") \ 1140 V(kInvalidLeftHandSideInAssignment, "Invalid left-hand side in assignment") \ 1141 V(kInvalidLhsInCompoundAssignment, "Invalid lhs in compound assignment") \ 1142 V(kInvalidLhsInCountOperation, "Invalid lhs in count operation") \ 1143 V(kInvalidMinLength, "Invalid min_length") \ 1144 V(kJSGlobalObjectNativeContextShouldBeANativeContext, \ 1145 "JSGlobalObject::native_context should be a native context") \ 1146 V(kJSGlobalProxyContextShouldNotBeNull, \ 1147 "JSGlobalProxy::context() should not be null") \ 1148 V(kJSObjectWithFastElementsMapHasSlowElements, \ 1149 "JSObject with fast elements map has slow elements") \ 1150 V(kLetBindingReInitialization, "Let binding re-initialization") \ 1151 V(kLhsHasBeenClobbered, "lhs has been clobbered") \ 1152 V(kLiveBytesCountOverflowChunkSize, "Live Bytes Count overflow chunk size") \ 1153 V(kLiveEditFrameDroppingIsNotSupportedOnARM64, \ 1154 "LiveEdit frame dropping is not supported on arm64") \ 1155 V(kLiveEditFrameDroppingIsNotSupportedOnArm, \ 1156 "LiveEdit frame dropping is not supported on arm") \ 1157 V(kLiveEditFrameDroppingIsNotSupportedOnMips, \ 1158 "LiveEdit frame dropping is not supported on mips") \ 1159 V(kLiveEdit, "LiveEdit") \ 1160 V(kLookupVariableInCountOperation, \ 1161 "Lookup variable in count operation") \ 1162 V(kMapBecameDeprecated, "Map became deprecated") \ 1163 V(kMapBecameUnstable, "Map became unstable") \ 1164 V(kMapIsNoLongerInEax, "Map is no longer in eax") \ 1165 V(kModuleDeclaration, "Module declaration") \ 1166 V(kModuleLiteral, "Module literal") \ 1167 V(kModulePath, "Module path") \ 1168 V(kModuleStatement, "Module statement") \ 1169 V(kModuleVariable, "Module variable") \ 1170 V(kModuleUrl, "Module url") \ 1171 V(kNativeFunctionLiteral, "Native function literal") \ 1172 V(kNeedSmiLiteral, "Need a Smi literal here") \ 1173 V(kNoCasesLeft, "No cases left") \ 1174 V(kNoEmptyArraysHereInEmitFastAsciiArrayJoin, \ 1175 "No empty arrays here in EmitFastAsciiArrayJoin") \ 1176 V(kNonInitializerAssignmentToConst, \ 1177 "Non-initializer assignment to const") \ 1178 V(kNonSmiIndex, "Non-smi index") \ 1179 V(kNonSmiKeyInArrayLiteral, "Non-smi key in array literal") \ 1180 V(kNonSmiValue, "Non-smi value") \ 1181 V(kNonObject, "Non-object value") \ 1182 V(kNotEnoughVirtualRegistersForValues, \ 1183 "Not enough virtual registers for values") \ 1184 V(kNotEnoughSpillSlotsForOsr, \ 1185 "Not enough spill slots for OSR") \ 1186 V(kNotEnoughVirtualRegistersRegalloc, \ 1187 "Not enough virtual registers (regalloc)") \ 1188 V(kObjectFoundInSmiOnlyArray, "Object found in smi-only array") \ 1189 V(kObjectLiteralWithComplexProperty, \ 1190 "Object literal with complex property") \ 1191 V(kOddballInStringTableIsNotUndefinedOrTheHole, \ 1192 "Oddball in string table is not undefined or the hole") \ 1193 V(kOffsetOutOfRange, "Offset out of range") \ 1194 V(kOperandIsASmiAndNotAName, "Operand is a smi and not a name") \ 1195 V(kOperandIsASmiAndNotAString, "Operand is a smi and not a string") \ 1196 V(kOperandIsASmi, "Operand is a smi") \ 1197 V(kOperandIsNotAName, "Operand is not a name") \ 1198 V(kOperandIsNotANumber, "Operand is not a number") \ 1199 V(kOperandIsNotASmi, "Operand is not a smi") \ 1200 V(kOperandIsNotAString, "Operand is not a string") \ 1201 V(kOperandIsNotSmi, "Operand is not smi") \ 1202 V(kOperandNotANumber, "Operand not a number") \ 1203 V(kObjectTagged, "The object is tagged") \ 1204 V(kObjectNotTagged, "The object is not tagged") \ 1205 V(kOptimizationDisabled, "Optimization is disabled") \ 1206 V(kOptimizedTooManyTimes, "Optimized too many times") \ 1207 V(kOutOfVirtualRegistersWhileTryingToAllocateTempRegister, \ 1208 "Out of virtual registers while trying to allocate temp register") \ 1209 V(kParseScopeError, "Parse/scope error") \ 1210 V(kPossibleDirectCallToEval, "Possible direct call to eval") \ 1211 V(kPreconditionsWereNotMet, "Preconditions were not met") \ 1212 V(kPropertyAllocationCountFailed, "Property allocation count failed") \ 1213 V(kReceivedInvalidReturnAddress, "Received invalid return address") \ 1214 V(kReferenceToAVariableWhichRequiresDynamicLookup, \ 1215 "Reference to a variable which requires dynamic lookup") \ 1216 V(kReferenceToGlobalLexicalVariable, \ 1217 "Reference to global lexical variable") \ 1218 V(kReferenceToUninitializedVariable, "Reference to uninitialized variable") \ 1219 V(kRegisterDidNotMatchExpectedRoot, "Register did not match expected root") \ 1220 V(kRegisterWasClobbered, "Register was clobbered") \ 1221 V(kRememberedSetPointerInNewSpace, "Remembered set pointer is in new space") \ 1222 V(kReturnAddressNotFoundInFrame, "Return address not found in frame") \ 1223 V(kRhsHasBeenClobbered, "Rhs has been clobbered") \ 1224 V(kScopedBlock, "ScopedBlock") \ 1225 V(kSmiAdditionOverflow, "Smi addition overflow") \ 1226 V(kSmiSubtractionOverflow, "Smi subtraction overflow") \ 1227 V(kStackAccessBelowStackPointer, "Stack access below stack pointer") \ 1228 V(kStackFrameTypesMustMatch, "Stack frame types must match") \ 1229 V(kSwitchStatementMixedOrNonLiteralSwitchLabels, \ 1230 "SwitchStatement: mixed or non-literal switch labels") \ 1231 V(kSwitchStatementTooManyClauses, "SwitchStatement: too many clauses") \ 1232 V(kTheCurrentStackPointerIsBelowCsp, \ 1233 "The current stack pointer is below csp") \ 1234 V(kTheInstructionShouldBeALui, "The instruction should be a lui") \ 1235 V(kTheInstructionShouldBeAnOri, "The instruction should be an ori") \ 1236 V(kTheInstructionToPatchShouldBeALoadFromPc, \ 1237 "The instruction to patch should be a load from pc") \ 1238 V(kTheInstructionToPatchShouldBeALoadFromPp, \ 1239 "The instruction to patch should be a load from pp") \ 1240 V(kTheInstructionToPatchShouldBeAnLdrLiteral, \ 1241 "The instruction to patch should be a ldr literal") \ 1242 V(kTheInstructionToPatchShouldBeALui, \ 1243 "The instruction to patch should be a lui") \ 1244 V(kTheInstructionToPatchShouldBeAnOri, \ 1245 "The instruction to patch should be an ori") \ 1246 V(kTheSourceAndDestinationAreTheSame, \ 1247 "The source and destination are the same") \ 1248 V(kTheStackPointerIsNotAligned, "The stack pointer is not aligned.") \ 1249 V(kTheStackWasCorruptedByMacroAssemblerCall, \ 1250 "The stack was corrupted by MacroAssembler::Call()") \ 1251 V(kTooManyParametersLocals, "Too many parameters/locals") \ 1252 V(kTooManyParameters, "Too many parameters") \ 1253 V(kTooManySpillSlotsNeededForOSR, "Too many spill slots needed for OSR") \ 1254 V(kToOperand32UnsupportedImmediate, "ToOperand32 unsupported immediate.") \ 1255 V(kToOperandIsDoubleRegisterUnimplemented, \ 1256 "ToOperand IsDoubleRegister unimplemented") \ 1257 V(kToOperandUnsupportedDoubleImmediate, \ 1258 "ToOperand Unsupported double immediate") \ 1259 V(kTryCatchStatement, "TryCatchStatement") \ 1260 V(kTryFinallyStatement, "TryFinallyStatement") \ 1261 V(kUnableToEncodeValueAsSmi, "Unable to encode value as smi") \ 1262 V(kUnalignedAllocationInNewSpace, "Unaligned allocation in new space") \ 1263 V(kUnalignedCellInWriteBarrier, "Unaligned cell in write barrier") \ 1264 V(kUndefinedValueNotLoaded, "Undefined value not loaded") \ 1265 V(kUndoAllocationOfNonAllocatedMemory, \ 1266 "Undo allocation of non allocated memory") \ 1267 V(kUnexpectedAllocationTop, "Unexpected allocation top") \ 1268 V(kUnexpectedColorFound, "Unexpected color bit pattern found") \ 1269 V(kUnexpectedElementsKindInArrayConstructor, \ 1270 "Unexpected ElementsKind in array constructor") \ 1271 V(kUnexpectedFallthroughFromCharCodeAtSlowCase, \ 1272 "Unexpected fallthrough from CharCodeAt slow case") \ 1273 V(kUnexpectedFallthroughFromCharFromCodeSlowCase, \ 1274 "Unexpected fallthrough from CharFromCode slow case") \ 1275 V(kUnexpectedFallThroughFromStringComparison, \ 1276 "Unexpected fall-through from string comparison") \ 1277 V(kUnexpectedFallThroughInBinaryStubGenerateFloatingPointCode, \ 1278 "Unexpected fall-through in BinaryStub_GenerateFloatingPointCode") \ 1279 V(kUnexpectedFallthroughToCharCodeAtSlowCase, \ 1280 "Unexpected fallthrough to CharCodeAt slow case") \ 1281 V(kUnexpectedFallthroughToCharFromCodeSlowCase, \ 1282 "Unexpected fallthrough to CharFromCode slow case") \ 1283 V(kUnexpectedFPUStackDepthAfterInstruction, \ 1284 "Unexpected FPU stack depth after instruction") \ 1285 V(kUnexpectedInitialMapForArrayFunction1, \ 1286 "Unexpected initial map for Array function (1)") \ 1287 V(kUnexpectedInitialMapForArrayFunction2, \ 1288 "Unexpected initial map for Array function (2)") \ 1289 V(kUnexpectedInitialMapForArrayFunction, \ 1290 "Unexpected initial map for Array function") \ 1291 V(kUnexpectedInitialMapForInternalArrayFunction, \ 1292 "Unexpected initial map for InternalArray function") \ 1293 V(kUnexpectedLevelAfterReturnFromApiCall, \ 1294 "Unexpected level after return from api call") \ 1295 V(kUnexpectedNegativeValue, "Unexpected negative value") \ 1296 V(kUnexpectedNumberOfPreAllocatedPropertyFields, \ 1297 "Unexpected number of pre-allocated property fields") \ 1298 V(kUnexpectedFPCRMode, "Unexpected FPCR mode.") \ 1299 V(kUnexpectedSmi, "Unexpected smi value") \ 1300 V(kUnexpectedStringFunction, "Unexpected String function") \ 1301 V(kUnexpectedStringType, "Unexpected string type") \ 1302 V(kUnexpectedStringWrapperInstanceSize, \ 1303 "Unexpected string wrapper instance size") \ 1304 V(kUnexpectedTypeForRegExpDataFixedArrayExpected, \ 1305 "Unexpected type for RegExp data, FixedArray expected") \ 1306 V(kUnexpectedValue, "Unexpected value") \ 1307 V(kUnexpectedUnusedPropertiesOfStringWrapper, \ 1308 "Unexpected unused properties of string wrapper") \ 1309 V(kUnimplemented, "unimplemented") \ 1310 V(kUninitializedKSmiConstantRegister, "Uninitialized kSmiConstantRegister") \ 1311 V(kUnknown, "Unknown") \ 1312 V(kUnsupportedConstCompoundAssignment, \ 1313 "Unsupported const compound assignment") \ 1314 V(kUnsupportedCountOperationWithConst, \ 1315 "Unsupported count operation with const") \ 1316 V(kUnsupportedDoubleImmediate, "Unsupported double immediate") \ 1317 V(kUnsupportedLetCompoundAssignment, "Unsupported let compound assignment") \ 1318 V(kUnsupportedLookupSlotInDeclaration, \ 1319 "Unsupported lookup slot in declaration") \ 1320 V(kUnsupportedNonPrimitiveCompare, "Unsupported non-primitive compare") \ 1321 V(kUnsupportedPhiUseOfArguments, "Unsupported phi use of arguments") \ 1322 V(kUnsupportedPhiUseOfConstVariable, \ 1323 "Unsupported phi use of const variable") \ 1324 V(kUnsupportedTaggedImmediate, "Unsupported tagged immediate") \ 1325 V(kVariableResolvedToWithContext, "Variable resolved to with context") \ 1326 V(kWeShouldNotHaveAnEmptyLexicalContext, \ 1327 "We should not have an empty lexical context") \ 1328 V(kWithStatement, "WithStatement") \ 1329 V(kWrongAddressOrValuePassedToRecordWrite, \ 1330 "Wrong address or value passed to RecordWrite") \ 1331 V(kYield, "Yield") 1332 1333 1334 #define ERROR_MESSAGES_CONSTANTS(C, T) C, 1335 enum BailoutReason { 1336 ERROR_MESSAGES_LIST(ERROR_MESSAGES_CONSTANTS) 1337 kLastErrorMessage 1338 }; 1339 #undef ERROR_MESSAGES_CONSTANTS 1340 1341 1342 const char* GetBailoutReason(BailoutReason reason); 1343 1344 1345 // Object is the abstract superclass for all classes in the 1346 // object hierarchy. 1347 // Object does not use any virtual functions to avoid the 1348 // allocation of the C++ vtable. 1349 // Since both Smi and HeapObject are subclasses of Object no 1350 // data members can be present in Object. 1351 class Object { 1352 public: 1353 // Type testing. 1354 bool IsObject() { return true; } 1355 1356 #define IS_TYPE_FUNCTION_DECL(type_) inline bool Is##type_(); 1357 OBJECT_TYPE_LIST(IS_TYPE_FUNCTION_DECL) 1358 HEAP_OBJECT_TYPE_LIST(IS_TYPE_FUNCTION_DECL) 1359 #undef IS_TYPE_FUNCTION_DECL 1360 1361 inline bool IsFixedArrayBase(); 1362 inline bool IsExternal(); 1363 inline bool IsAccessorInfo(); 1364 1365 inline bool IsStruct(); 1366 #define DECLARE_STRUCT_PREDICATE(NAME, Name, name) inline bool Is##Name(); 1367 STRUCT_LIST(DECLARE_STRUCT_PREDICATE) 1368 #undef DECLARE_STRUCT_PREDICATE 1369 1370 INLINE(bool IsSpecObject()); 1371 INLINE(bool IsSpecFunction()); 1372 INLINE(bool IsTemplateInfo()); 1373 bool IsCallable(); 1374 1375 // Oddball testing. 1376 INLINE(bool IsUndefined()); 1377 INLINE(bool IsNull()); 1378 INLINE(bool IsTheHole()); 1379 INLINE(bool IsException()); 1380 INLINE(bool IsUninitialized()); 1381 INLINE(bool IsTrue()); 1382 INLINE(bool IsFalse()); 1383 inline bool IsArgumentsMarker(); 1384 1385 // Filler objects (fillers and free space objects). 1386 inline bool IsFiller(); 1387 1388 // Extract the number. 1389 inline double Number(); 1390 inline bool IsNaN(); 1391 bool ToInt32(int32_t* value); 1392 bool ToUint32(uint32_t* value); 1393 1394 // Indicates whether OptimalRepresentation can do its work, or whether it 1395 // always has to return Representation::Tagged(). 1396 enum ValueType { 1397 OPTIMAL_REPRESENTATION, 1398 FORCE_TAGGED 1399 }; 1400 1401 inline Representation OptimalRepresentation( 1402 ValueType type = OPTIMAL_REPRESENTATION) { 1403 if (!FLAG_track_fields) return Representation::Tagged(); 1404 if (type == FORCE_TAGGED) return Representation::Tagged(); 1405 if (IsSmi()) { 1406 return Representation::Smi(); 1407 } else if (FLAG_track_double_fields && IsHeapNumber()) { 1408 return Representation::Double(); 1409 } else if (FLAG_track_computed_fields && IsUninitialized()) { 1410 return Representation::None(); 1411 } else if (FLAG_track_heap_object_fields) { 1412 ASSERT(IsHeapObject()); 1413 return Representation::HeapObject(); 1414 } else { 1415 return Representation::Tagged(); 1416 } 1417 } 1418 1419 inline bool FitsRepresentation(Representation representation) { 1420 if (FLAG_track_fields && representation.IsNone()) { 1421 return false; 1422 } else if (FLAG_track_fields && representation.IsSmi()) { 1423 return IsSmi(); 1424 } else if (FLAG_track_double_fields && representation.IsDouble()) { 1425 return IsNumber(); 1426 } else if (FLAG_track_heap_object_fields && representation.IsHeapObject()) { 1427 return IsHeapObject(); 1428 } 1429 return true; 1430 } 1431 1432 Handle<HeapType> OptimalType(Isolate* isolate, Representation representation); 1433 1434 inline static Handle<Object> NewStorageFor(Isolate* isolate, 1435 Handle<Object> object, 1436 Representation representation); 1437 1438 // Returns true if the object is of the correct type to be used as a 1439 // implementation of a JSObject's elements. 1440 inline bool HasValidElements(); 1441 1442 inline bool HasSpecificClassOf(String* name); 1443 1444 bool BooleanValue(); // ECMA-262 9.2. 1445 1446 // Convert to a JSObject if needed. 1447 // native_context is used when creating wrapper object. 1448 static inline MaybeHandle<JSReceiver> ToObject(Isolate* isolate, 1449 Handle<Object> object); 1450 static MaybeHandle<JSReceiver> ToObject(Isolate* isolate, 1451 Handle<Object> object, 1452 Handle<Context> context); 1453 1454 // Converts this to a Smi if possible. 1455 static MUST_USE_RESULT inline MaybeHandle<Smi> ToSmi(Isolate* isolate, 1456 Handle<Object> object); 1457 1458 void Lookup(Handle<Name> name, LookupResult* result); 1459 1460 MUST_USE_RESULT static MaybeHandle<Object> GetProperty(LookupIterator* it); 1461 MUST_USE_RESULT static inline MaybeHandle<Object> GetPropertyOrElement( 1462 Handle<Object> object, 1463 Handle<Name> key); 1464 MUST_USE_RESULT static inline MaybeHandle<Object> GetProperty( 1465 Isolate* isolate, 1466 Handle<Object> object, 1467 const char* key); 1468 MUST_USE_RESULT static inline MaybeHandle<Object> GetProperty( 1469 Handle<Object> object, 1470 Handle<Name> key); 1471 1472 MUST_USE_RESULT static MaybeHandle<Object> GetPropertyWithAccessor( 1473 Handle<Object> receiver, 1474 Handle<Name> name, 1475 Handle<JSObject> holder, 1476 Handle<Object> structure); 1477 MUST_USE_RESULT static MaybeHandle<Object> SetPropertyWithCallback( 1478 Handle<Object> receiver, 1479 Handle<Name> name, 1480 Handle<Object> value, 1481 Handle<JSObject> holder, 1482 Handle<Object> structure, 1483 StrictMode strict_mode); 1484 1485 MUST_USE_RESULT static MaybeHandle<Object> GetPropertyWithDefinedGetter( 1486 Handle<Object> receiver, 1487 Handle<JSReceiver> getter); 1488 MUST_USE_RESULT static MaybeHandle<Object> SetPropertyWithDefinedSetter( 1489 Handle<Object> receiver, 1490 Handle<JSReceiver> setter, 1491 Handle<Object> value); 1492 1493 MUST_USE_RESULT static inline MaybeHandle<Object> GetElement( 1494 Isolate* isolate, 1495 Handle<Object> object, 1496 uint32_t index); 1497 1498 MUST_USE_RESULT static MaybeHandle<Object> GetElementWithReceiver( 1499 Isolate* isolate, 1500 Handle<Object> object, 1501 Handle<Object> receiver, 1502 uint32_t index); 1503 1504 // Return the object's prototype (might be Heap::null_value()). 1505 Object* GetPrototype(Isolate* isolate); 1506 static Handle<Object> GetPrototype(Isolate* isolate, Handle<Object> object); 1507 1508 // Returns the permanent hash code associated with this object. May return 1509 // undefined if not yet created. 1510 Object* GetHash(); 1511 1512 // Returns the permanent hash code associated with this object depending on 1513 // the actual object type. May create and store a hash code if needed and none 1514 // exists. 1515 static Handle<Smi> GetOrCreateHash(Isolate* isolate, Handle<Object> object); 1516 1517 // Checks whether this object has the same value as the given one. This 1518 // function is implemented according to ES5, section 9.12 and can be used 1519 // to implement the Harmony "egal" function. 1520 bool SameValue(Object* other); 1521 1522 // Checks whether this object has the same value as the given one. 1523 // +0 and -0 are treated equal. Everything else is the same as SameValue. 1524 // This function is implemented according to ES6, section 7.2.4 and is used 1525 // by ES6 Map and Set. 1526 bool SameValueZero(Object* other); 1527 1528 // Tries to convert an object to an array index. Returns true and sets 1529 // the output parameter if it succeeds. 1530 inline bool ToArrayIndex(uint32_t* index); 1531 1532 // Returns true if this is a JSValue containing a string and the index is 1533 // < the length of the string. Used to implement [] on strings. 1534 inline bool IsStringObjectWithCharacterAt(uint32_t index); 1535 1536 DECLARE_VERIFIER(Object) 1537 #ifdef VERIFY_HEAP 1538 // Verify a pointer is a valid object pointer. 1539 static void VerifyPointer(Object* p); 1540 #endif 1541 1542 inline void VerifyApiCallResultType(); 1543 1544 // Prints this object without details. 1545 void ShortPrint(FILE* out = stdout); 1546 1547 // Prints this object without details to a message accumulator. 1548 void ShortPrint(StringStream* accumulator); 1549 1550 // Casting: This cast is only needed to satisfy macros in objects-inl.h. 1551 static Object* cast(Object* value) { return value; } 1552 1553 // Layout description. 1554 static const int kHeaderSize = 0; // Object does not take up any space. 1555 1556 #ifdef OBJECT_PRINT 1557 // Prints this object with details. 1558 void Print(); 1559 void Print(FILE* out); 1560 void PrintLn(); 1561 void PrintLn(FILE* out); 1562 #endif 1563 1564 private: 1565 DISALLOW_IMPLICIT_CONSTRUCTORS(Object); 1566 }; 1567 1568 1569 // Smi represents integer Numbers that can be stored in 31 bits. 1570 // Smis are immediate which means they are NOT allocated in the heap. 1571 // The this pointer has the following format: [31 bit signed int] 0 1572 // For long smis it has the following format: 1573 // [32 bit signed int] [31 bits zero padding] 0 1574 // Smi stands for small integer. 1575 class Smi: public Object { 1576 public: 1577 // Returns the integer value. 1578 inline int value(); 1579 1580 // Convert a value to a Smi object. 1581 static inline Smi* FromInt(int value); 1582 1583 static inline Smi* FromIntptr(intptr_t value); 1584 1585 // Returns whether value can be represented in a Smi. 1586 static inline bool IsValid(intptr_t value); 1587 1588 // Casting. 1589 static inline Smi* cast(Object* object); 1590 1591 // Dispatched behavior. 1592 void SmiPrint(FILE* out = stdout); 1593 void SmiPrint(StringStream* accumulator); 1594 1595 DECLARE_VERIFIER(Smi) 1596 1597 static const int kMinValue = 1598 (static_cast<unsigned int>(-1)) << (kSmiValueSize - 1); 1599 static const int kMaxValue = -(kMinValue + 1); 1600 1601 private: 1602 DISALLOW_IMPLICIT_CONSTRUCTORS(Smi); 1603 }; 1604 1605 1606 // Heap objects typically have a map pointer in their first word. However, 1607 // during GC other data (e.g. mark bits, forwarding addresses) is sometimes 1608 // encoded in the first word. The class MapWord is an abstraction of the 1609 // value in a heap object's first word. 1610 class MapWord BASE_EMBEDDED { 1611 public: 1612 // Normal state: the map word contains a map pointer. 1613 1614 // Create a map word from a map pointer. 1615 static inline MapWord FromMap(Map* map); 1616 1617 // View this map word as a map pointer. 1618 inline Map* ToMap(); 1619 1620 1621 // Scavenge collection: the map word of live objects in the from space 1622 // contains a forwarding address (a heap object pointer in the to space). 1623 1624 // True if this map word is a forwarding address for a scavenge 1625 // collection. Only valid during a scavenge collection (specifically, 1626 // when all map words are heap object pointers, i.e. not during a full GC). 1627 inline bool IsForwardingAddress(); 1628 1629 // Create a map word from a forwarding address. 1630 static inline MapWord FromForwardingAddress(HeapObject* object); 1631 1632 // View this map word as a forwarding address. 1633 inline HeapObject* ToForwardingAddress(); 1634 1635 static inline MapWord FromRawValue(uintptr_t value) { 1636 return MapWord(value); 1637 } 1638 1639 inline uintptr_t ToRawValue() { 1640 return value_; 1641 } 1642 1643 private: 1644 // HeapObject calls the private constructor and directly reads the value. 1645 friend class HeapObject; 1646 1647 explicit MapWord(uintptr_t value) : value_(value) {} 1648 1649 uintptr_t value_; 1650 }; 1651 1652 1653 // HeapObject is the superclass for all classes describing heap allocated 1654 // objects. 1655 class HeapObject: public Object { 1656 public: 1657 // [map]: Contains a map which contains the object's reflective 1658 // information. 1659 inline Map* map(); 1660 inline void set_map(Map* value); 1661 // The no-write-barrier version. This is OK if the object is white and in 1662 // new space, or if the value is an immortal immutable object, like the maps 1663 // of primitive (non-JS) objects like strings, heap numbers etc. 1664 inline void set_map_no_write_barrier(Map* value); 1665 1666 // Get the map using acquire load. 1667 inline Map* synchronized_map(); 1668 inline MapWord synchronized_map_word(); 1669 1670 // Set the map using release store 1671 inline void synchronized_set_map(Map* value); 1672 inline void synchronized_set_map_no_write_barrier(Map* value); 1673 inline void synchronized_set_map_word(MapWord map_word); 1674 1675 // During garbage collection, the map word of a heap object does not 1676 // necessarily contain a map pointer. 1677 inline MapWord map_word(); 1678 inline void set_map_word(MapWord map_word); 1679 1680 // The Heap the object was allocated in. Used also to access Isolate. 1681 inline Heap* GetHeap(); 1682 1683 // Convenience method to get current isolate. 1684 inline Isolate* GetIsolate(); 1685 1686 // Converts an address to a HeapObject pointer. 1687 static inline HeapObject* FromAddress(Address address); 1688 1689 // Returns the address of this HeapObject. 1690 inline Address address(); 1691 1692 // Iterates over pointers contained in the object (including the Map) 1693 void Iterate(ObjectVisitor* v); 1694 1695 // Iterates over all pointers contained in the object except the 1696 // first map pointer. The object type is given in the first 1697 // parameter. This function does not access the map pointer in the 1698 // object, and so is safe to call while the map pointer is modified. 1699 void IterateBody(InstanceType type, int object_size, ObjectVisitor* v); 1700 1701 // Returns the heap object's size in bytes 1702 inline int Size(); 1703 1704 // Given a heap object's map pointer, returns the heap size in bytes 1705 // Useful when the map pointer field is used for other purposes. 1706 // GC internal. 1707 inline int SizeFromMap(Map* map); 1708 1709 // Returns the field at offset in obj, as a read/write Object* reference. 1710 // Does no checking, and is safe to use during GC, while maps are invalid. 1711 // Does not invoke write barrier, so should only be assigned to 1712 // during marking GC. 1713 static inline Object** RawField(HeapObject* obj, int offset); 1714 1715 // Adds the |code| object related to |name| to the code cache of this map. If 1716 // this map is a dictionary map that is shared, the map copied and installed 1717 // onto the object. 1718 static void UpdateMapCodeCache(Handle<HeapObject> object, 1719 Handle<Name> name, 1720 Handle<Code> code); 1721 1722 // Casting. 1723 static inline HeapObject* cast(Object* obj); 1724 1725 // Return the write barrier mode for this. Callers of this function 1726 // must be able to present a reference to an DisallowHeapAllocation 1727 // object as a sign that they are not going to use this function 1728 // from code that allocates and thus invalidates the returned write 1729 // barrier mode. 1730 inline WriteBarrierMode GetWriteBarrierMode( 1731 const DisallowHeapAllocation& promise); 1732 1733 // Dispatched behavior. 1734 void HeapObjectShortPrint(StringStream* accumulator); 1735 #ifdef OBJECT_PRINT 1736 void PrintHeader(FILE* out, const char* id); 1737 #endif 1738 DECLARE_PRINTER(HeapObject) 1739 DECLARE_VERIFIER(HeapObject) 1740 #ifdef VERIFY_HEAP 1741 inline void VerifyObjectField(int offset); 1742 inline void VerifySmiField(int offset); 1743 1744 // Verify a pointer is a valid HeapObject pointer that points to object 1745 // areas in the heap. 1746 static void VerifyHeapPointer(Object* p); 1747 #endif 1748 1749 // Layout description. 1750 // First field in a heap object is map. 1751 static const int kMapOffset = Object::kHeaderSize; 1752 static const int kHeaderSize = kMapOffset + kPointerSize; 1753 1754 STATIC_ASSERT(kMapOffset == Internals::kHeapObjectMapOffset); 1755 1756 protected: 1757 // helpers for calling an ObjectVisitor to iterate over pointers in the 1758 // half-open range [start, end) specified as integer offsets 1759 inline void IteratePointers(ObjectVisitor* v, int start, int end); 1760 // as above, for the single element at "offset" 1761 inline void IteratePointer(ObjectVisitor* v, int offset); 1762 // as above, for the next code link of a code object. 1763 inline void IterateNextCodeLink(ObjectVisitor* v, int offset); 1764 1765 private: 1766 DISALLOW_IMPLICIT_CONSTRUCTORS(HeapObject); 1767 }; 1768 1769 1770 // This class describes a body of an object of a fixed size 1771 // in which all pointer fields are located in the [start_offset, end_offset) 1772 // interval. 1773 template<int start_offset, int end_offset, int size> 1774 class FixedBodyDescriptor { 1775 public: 1776 static const int kStartOffset = start_offset; 1777 static const int kEndOffset = end_offset; 1778 static const int kSize = size; 1779 1780 static inline void IterateBody(HeapObject* obj, ObjectVisitor* v); 1781 1782 template<typename StaticVisitor> 1783 static inline void IterateBody(HeapObject* obj) { 1784 StaticVisitor::VisitPointers(HeapObject::RawField(obj, start_offset), 1785 HeapObject::RawField(obj, end_offset)); 1786 } 1787 }; 1788 1789 1790 // This class describes a body of an object of a variable size 1791 // in which all pointer fields are located in the [start_offset, object_size) 1792 // interval. 1793 template<int start_offset> 1794 class FlexibleBodyDescriptor { 1795 public: 1796 static const int kStartOffset = start_offset; 1797 1798 static inline void IterateBody(HeapObject* obj, 1799 int object_size, 1800 ObjectVisitor* v); 1801 1802 template<typename StaticVisitor> 1803 static inline void IterateBody(HeapObject* obj, int object_size) { 1804 StaticVisitor::VisitPointers(HeapObject::RawField(obj, start_offset), 1805 HeapObject::RawField(obj, object_size)); 1806 } 1807 }; 1808 1809 1810 // The HeapNumber class describes heap allocated numbers that cannot be 1811 // represented in a Smi (small integer) 1812 class HeapNumber: public HeapObject { 1813 public: 1814 // [value]: number value. 1815 inline double value(); 1816 inline void set_value(double value); 1817 1818 // Casting. 1819 static inline HeapNumber* cast(Object* obj); 1820 1821 // Dispatched behavior. 1822 bool HeapNumberBooleanValue(); 1823 1824 void HeapNumberPrint(FILE* out = stdout); 1825 void HeapNumberPrint(StringStream* accumulator); 1826 DECLARE_VERIFIER(HeapNumber) 1827 1828 inline int get_exponent(); 1829 inline int get_sign(); 1830 1831 // Layout description. 1832 static const int kValueOffset = HeapObject::kHeaderSize; 1833 // IEEE doubles are two 32 bit words. The first is just mantissa, the second 1834 // is a mixture of sign, exponent and mantissa. The offsets of two 32 bit 1835 // words within double numbers are endian dependent and they are set 1836 // accordingly. 1837 #if defined(V8_TARGET_LITTLE_ENDIAN) 1838 static const int kMantissaOffset = kValueOffset; 1839 static const int kExponentOffset = kValueOffset + 4; 1840 #elif defined(V8_TARGET_BIG_ENDIAN) 1841 static const int kMantissaOffset = kValueOffset + 4; 1842 static const int kExponentOffset = kValueOffset; 1843 #else 1844 #error Unknown byte ordering 1845 #endif 1846 1847 static const int kSize = kValueOffset + kDoubleSize; 1848 static const uint32_t kSignMask = 0x80000000u; 1849 static const uint32_t kExponentMask = 0x7ff00000u; 1850 static const uint32_t kMantissaMask = 0xfffffu; 1851 static const int kMantissaBits = 52; 1852 static const int kExponentBits = 11; 1853 static const int kExponentBias = 1023; 1854 static const int kExponentShift = 20; 1855 static const int kInfinityOrNanExponent = 1856 (kExponentMask >> kExponentShift) - kExponentBias; 1857 static const int kMantissaBitsInTopWord = 20; 1858 static const int kNonMantissaBitsInTopWord = 12; 1859 1860 private: 1861 DISALLOW_IMPLICIT_CONSTRUCTORS(HeapNumber); 1862 }; 1863 1864 1865 enum EnsureElementsMode { 1866 DONT_ALLOW_DOUBLE_ELEMENTS, 1867 ALLOW_COPIED_DOUBLE_ELEMENTS, 1868 ALLOW_CONVERTED_DOUBLE_ELEMENTS 1869 }; 1870 1871 1872 // Indicates whether a property should be set or (re)defined. Setting of a 1873 // property causes attributes to remain unchanged, writability to be checked 1874 // and callbacks to be called. Defining of a property causes attributes to 1875 // be updated and callbacks to be overridden. 1876 enum SetPropertyMode { 1877 SET_PROPERTY, 1878 DEFINE_PROPERTY 1879 }; 1880 1881 1882 // Indicator for one component of an AccessorPair. 1883 enum AccessorComponent { 1884 ACCESSOR_GETTER, 1885 ACCESSOR_SETTER 1886 }; 1887 1888 1889 // JSReceiver includes types on which properties can be defined, i.e., 1890 // JSObject and JSProxy. 1891 class JSReceiver: public HeapObject { 1892 public: 1893 enum DeleteMode { 1894 NORMAL_DELETION, 1895 STRICT_DELETION, 1896 FORCE_DELETION 1897 }; 1898 1899 // A non-keyed store is of the form a.x = foo or a["x"] = foo whereas 1900 // a keyed store is of the form a[expression] = foo. 1901 enum StoreFromKeyed { 1902 MAY_BE_STORE_FROM_KEYED, 1903 CERTAINLY_NOT_STORE_FROM_KEYED 1904 }; 1905 1906 // Internal properties (e.g. the hidden properties dictionary) might 1907 // be added even though the receiver is non-extensible. 1908 enum ExtensibilityCheck { 1909 PERFORM_EXTENSIBILITY_CHECK, 1910 OMIT_EXTENSIBILITY_CHECK 1911 }; 1912 1913 // Casting. 1914 static inline JSReceiver* cast(Object* obj); 1915 1916 // Implementation of [[Put]], ECMA-262 5th edition, section 8.12.5. 1917 MUST_USE_RESULT static MaybeHandle<Object> SetProperty( 1918 Handle<JSReceiver> object, 1919 Handle<Name> key, 1920 Handle<Object> value, 1921 PropertyAttributes attributes, 1922 StrictMode strict_mode, 1923 StoreFromKeyed store_mode = MAY_BE_STORE_FROM_KEYED); 1924 MUST_USE_RESULT static MaybeHandle<Object> SetElement( 1925 Handle<JSReceiver> object, 1926 uint32_t index, 1927 Handle<Object> value, 1928 PropertyAttributes attributes, 1929 StrictMode strict_mode); 1930 1931 // Implementation of [[HasProperty]], ECMA-262 5th edition, section 8.12.6. 1932 static inline bool HasProperty(Handle<JSReceiver> object, Handle<Name> name); 1933 static inline bool HasOwnProperty(Handle<JSReceiver>, Handle<Name> name); 1934 static inline bool HasElement(Handle<JSReceiver> object, uint32_t index); 1935 static inline bool HasOwnElement(Handle<JSReceiver> object, uint32_t index); 1936 1937 // Implementation of [[Delete]], ECMA-262 5th edition, section 8.12.7. 1938 MUST_USE_RESULT static MaybeHandle<Object> DeleteProperty( 1939 Handle<JSReceiver> object, 1940 Handle<Name> name, 1941 DeleteMode mode = NORMAL_DELETION); 1942 MUST_USE_RESULT static MaybeHandle<Object> DeleteElement( 1943 Handle<JSReceiver> object, 1944 uint32_t index, 1945 DeleteMode mode = NORMAL_DELETION); 1946 1947 // Tests for the fast common case for property enumeration. 1948 bool IsSimpleEnum(); 1949 1950 // Returns the class name ([[Class]] property in the specification). 1951 String* class_name(); 1952 1953 // Returns the constructor name (the name (possibly, inferred name) of the 1954 // function that was used to instantiate the object). 1955 String* constructor_name(); 1956 1957 static inline PropertyAttributes GetPropertyAttributes( 1958 Handle<JSReceiver> object, 1959 Handle<Name> name); 1960 static PropertyAttributes GetPropertyAttributes(LookupIterator* it); 1961 static PropertyAttributes GetOwnPropertyAttributes( 1962 Handle<JSReceiver> object, 1963 Handle<Name> name); 1964 1965 static inline PropertyAttributes GetElementAttribute( 1966 Handle<JSReceiver> object, 1967 uint32_t index); 1968 static inline PropertyAttributes GetOwnElementAttribute( 1969 Handle<JSReceiver> object, 1970 uint32_t index); 1971 1972 // Return the object's prototype (might be Heap::null_value()). 1973 inline Object* GetPrototype(); 1974 1975 // Return the constructor function (may be Heap::null_value()). 1976 inline Object* GetConstructor(); 1977 1978 // Retrieves a permanent object identity hash code. The undefined value might 1979 // be returned in case no hash was created yet. 1980 inline Object* GetIdentityHash(); 1981 1982 // Retrieves a permanent object identity hash code. May create and store a 1983 // hash code if needed and none exists. 1984 inline static Handle<Smi> GetOrCreateIdentityHash( 1985 Handle<JSReceiver> object); 1986 1987 // Lookup a property. If found, the result is valid and has 1988 // detailed information. 1989 void LookupOwn(Handle<Name> name, LookupResult* result, 1990 bool search_hidden_prototypes = false); 1991 void Lookup(Handle<Name> name, LookupResult* result); 1992 1993 enum KeyCollectionType { OWN_ONLY, INCLUDE_PROTOS }; 1994 1995 // Computes the enumerable keys for a JSObject. Used for implementing 1996 // "for (n in object) { }". 1997 MUST_USE_RESULT static MaybeHandle<FixedArray> GetKeys( 1998 Handle<JSReceiver> object, 1999 KeyCollectionType type); 2000 2001 private: 2002 MUST_USE_RESULT static MaybeHandle<Object> SetProperty( 2003 Handle<JSReceiver> receiver, 2004 LookupResult* result, 2005 Handle<Name> key, 2006 Handle<Object> value, 2007 PropertyAttributes attributes, 2008 StrictMode strict_mode, 2009 StoreFromKeyed store_from_keyed); 2010 2011 DISALLOW_IMPLICIT_CONSTRUCTORS(JSReceiver); 2012 }; 2013 2014 // Forward declaration for JSObject::GetOrCreateHiddenPropertiesHashTable. 2015 class ObjectHashTable; 2016 2017 // Forward declaration for JSObject::Copy. 2018 class AllocationSite; 2019 2020 2021 // The JSObject describes real heap allocated JavaScript objects with 2022 // properties. 2023 // Note that the map of JSObject changes during execution to enable inline 2024 // caching. 2025 class JSObject: public JSReceiver { 2026 public: 2027 // [properties]: Backing storage for properties. 2028 // properties is a FixedArray in the fast case and a Dictionary in the 2029 // slow case. 2030 DECL_ACCESSORS(properties, FixedArray) // Get and set fast properties. 2031 inline void initialize_properties(); 2032 inline bool HasFastProperties(); 2033 inline NameDictionary* property_dictionary(); // Gets slow properties. 2034 2035 // [elements]: The elements (properties with names that are integers). 2036 // 2037 // Elements can be in two general modes: fast and slow. Each mode 2038 // corrensponds to a set of object representations of elements that 2039 // have something in common. 2040 // 2041 // In the fast mode elements is a FixedArray and so each element can 2042 // be quickly accessed. This fact is used in the generated code. The 2043 // elements array can have one of three maps in this mode: 2044 // fixed_array_map, sloppy_arguments_elements_map or 2045 // fixed_cow_array_map (for copy-on-write arrays). In the latter case 2046 // the elements array may be shared by a few objects and so before 2047 // writing to any element the array must be copied. Use 2048 // EnsureWritableFastElements in this case. 2049 // 2050 // In the slow mode the elements is either a NumberDictionary, an 2051 // ExternalArray, or a FixedArray parameter map for a (sloppy) 2052 // arguments object. 2053 DECL_ACCESSORS(elements, FixedArrayBase) 2054 inline void initialize_elements(); 2055 static void ResetElements(Handle<JSObject> object); 2056 static inline void SetMapAndElements(Handle<JSObject> object, 2057 Handle<Map> map, 2058 Handle<FixedArrayBase> elements); 2059 inline ElementsKind GetElementsKind(); 2060 inline ElementsAccessor* GetElementsAccessor(); 2061 // Returns true if an object has elements of FAST_SMI_ELEMENTS ElementsKind. 2062 inline bool HasFastSmiElements(); 2063 // Returns true if an object has elements of FAST_ELEMENTS ElementsKind. 2064 inline bool HasFastObjectElements(); 2065 // Returns true if an object has elements of FAST_ELEMENTS or 2066 // FAST_SMI_ONLY_ELEMENTS. 2067 inline bool HasFastSmiOrObjectElements(); 2068 // Returns true if an object has any of the fast elements kinds. 2069 inline bool HasFastElements(); 2070 // Returns true if an object has elements of FAST_DOUBLE_ELEMENTS 2071 // ElementsKind. 2072 inline bool HasFastDoubleElements(); 2073 // Returns true if an object has elements of FAST_HOLEY_*_ELEMENTS 2074 // ElementsKind. 2075 inline bool HasFastHoleyElements(); 2076 inline bool HasSloppyArgumentsElements(); 2077 inline bool HasDictionaryElements(); 2078 2079 inline bool HasExternalUint8ClampedElements(); 2080 inline bool HasExternalArrayElements(); 2081 inline bool HasExternalInt8Elements(); 2082 inline bool HasExternalUint8Elements(); 2083 inline bool HasExternalInt16Elements(); 2084 inline bool HasExternalUint16Elements(); 2085 inline bool HasExternalInt32Elements(); 2086 inline bool HasExternalUint32Elements(); 2087 inline bool HasExternalFloat32Elements(); 2088 inline bool HasExternalFloat64Elements(); 2089 2090 inline bool HasFixedTypedArrayElements(); 2091 2092 inline bool HasFixedUint8ClampedElements(); 2093 inline bool HasFixedArrayElements(); 2094 inline bool HasFixedInt8Elements(); 2095 inline bool HasFixedUint8Elements(); 2096 inline bool HasFixedInt16Elements(); 2097 inline bool HasFixedUint16Elements(); 2098 inline bool HasFixedInt32Elements(); 2099 inline bool HasFixedUint32Elements(); 2100 inline bool HasFixedFloat32Elements(); 2101 inline bool HasFixedFloat64Elements(); 2102 2103 bool HasFastArgumentsElements(); 2104 bool HasDictionaryArgumentsElements(); 2105 inline SeededNumberDictionary* element_dictionary(); // Gets slow elements. 2106 2107 // Requires: HasFastElements(). 2108 static Handle<FixedArray> EnsureWritableFastElements( 2109 Handle<JSObject> object); 2110 2111 // Collects elements starting at index 0. 2112 // Undefined values are placed after non-undefined values. 2113 // Returns the number of non-undefined values. 2114 static Handle<Object> PrepareElementsForSort(Handle<JSObject> object, 2115 uint32_t limit); 2116 // As PrepareElementsForSort, but only on objects where elements is 2117 // a dictionary, and it will stay a dictionary. Collates undefined and 2118 // unexisting elements below limit from position zero of the elements. 2119 static Handle<Object> PrepareSlowElementsForSort(Handle<JSObject> object, 2120 uint32_t limit); 2121 2122 MUST_USE_RESULT static MaybeHandle<Object> SetPropertyWithInterceptor( 2123 Handle<JSObject> object, 2124 Handle<Name> name, 2125 Handle<Object> value, 2126 PropertyAttributes attributes, 2127 StrictMode strict_mode); 2128 2129 MUST_USE_RESULT static MaybeHandle<Object> SetPropertyForResult( 2130 Handle<JSObject> object, 2131 LookupResult* result, 2132 Handle<Name> name, 2133 Handle<Object> value, 2134 PropertyAttributes attributes, 2135 StrictMode strict_mode, 2136 StoreFromKeyed store_mode = MAY_BE_STORE_FROM_KEYED); 2137 2138 // SetLocalPropertyIgnoreAttributes converts callbacks to fields. We need to 2139 // grant an exemption to ExecutableAccessor callbacks in some cases. 2140 enum ExecutableAccessorInfoHandling { 2141 DEFAULT_HANDLING, 2142 DONT_FORCE_FIELD 2143 }; 2144 2145 MUST_USE_RESULT static MaybeHandle<Object> SetOwnPropertyIgnoreAttributes( 2146 Handle<JSObject> object, 2147 Handle<Name> key, 2148 Handle<Object> value, 2149 PropertyAttributes attributes, 2150 ValueType value_type = OPTIMAL_REPRESENTATION, 2151 StoreMode mode = ALLOW_AS_CONSTANT, 2152 ExtensibilityCheck extensibility_check = PERFORM_EXTENSIBILITY_CHECK, 2153 StoreFromKeyed store_mode = MAY_BE_STORE_FROM_KEYED, 2154 ExecutableAccessorInfoHandling handling = DEFAULT_HANDLING); 2155 2156 static inline Handle<String> ExpectedTransitionKey(Handle<Map> map); 2157 static inline Handle<Map> ExpectedTransitionTarget(Handle<Map> map); 2158 2159 // Try to follow an existing transition to a field with attributes NONE. The 2160 // return value indicates whether the transition was successful. 2161 static inline Handle<Map> FindTransitionToField(Handle<Map> map, 2162 Handle<Name> key); 2163 2164 // Extend the receiver with a single fast property appeared first in the 2165 // passed map. This also extends the property backing store if necessary. 2166 static void AllocateStorageForMap(Handle<JSObject> object, Handle<Map> map); 2167 2168 // Migrates the given object to a map whose field representations are the 2169 // lowest upper bound of all known representations for that field. 2170 static void MigrateInstance(Handle<JSObject> instance); 2171 2172 // Migrates the given object only if the target map is already available, 2173 // or returns false if such a map is not yet available. 2174 static bool TryMigrateInstance(Handle<JSObject> instance); 2175 2176 // Retrieve a value in a normalized object given a lookup result. 2177 // Handles the special representation of JS global objects. 2178 Object* GetNormalizedProperty(const LookupResult* result); 2179 static Handle<Object> GetNormalizedProperty(Handle<JSObject> object, 2180 const LookupResult* result); 2181 2182 // Sets the property value in a normalized object given a lookup result. 2183 // Handles the special representation of JS global objects. 2184 static void SetNormalizedProperty(Handle<JSObject> object, 2185 const LookupResult* result, 2186 Handle<Object> value); 2187 2188 // Sets the property value in a normalized object given (key, value, details). 2189 // Handles the special representation of JS global objects. 2190 static void SetNormalizedProperty(Handle<JSObject> object, 2191 Handle<Name> key, 2192 Handle<Object> value, 2193 PropertyDetails details); 2194 2195 static void OptimizeAsPrototype(Handle<JSObject> object); 2196 2197 // Retrieve interceptors. 2198 InterceptorInfo* GetNamedInterceptor(); 2199 InterceptorInfo* GetIndexedInterceptor(); 2200 2201 // Used from JSReceiver. 2202 static Maybe<PropertyAttributes> GetPropertyAttributesWithInterceptor( 2203 Handle<JSObject> holder, 2204 Handle<Object> receiver, 2205 Handle<Name> name); 2206 static PropertyAttributes GetPropertyAttributesWithFailedAccessCheck( 2207 LookupIterator* it); 2208 static PropertyAttributes GetElementAttributeWithReceiver( 2209 Handle<JSObject> object, 2210 Handle<JSReceiver> receiver, 2211 uint32_t index, 2212 bool check_prototype); 2213 2214 // Retrieves an AccessorPair property from the given object. Might return 2215 // undefined if the property doesn't exist or is of a different kind. 2216 MUST_USE_RESULT static MaybeHandle<Object> GetAccessor( 2217 Handle<JSObject> object, 2218 Handle<Name> name, 2219 AccessorComponent component); 2220 2221 // Defines an AccessorPair property on the given object. 2222 // TODO(mstarzinger): Rename to SetAccessor() and return empty handle on 2223 // exception instead of letting callers check for scheduled exception. 2224 static void DefineAccessor(Handle<JSObject> object, 2225 Handle<Name> name, 2226 Handle<Object> getter, 2227 Handle<Object> setter, 2228 PropertyAttributes attributes, 2229 v8::AccessControl access_control = v8::DEFAULT); 2230 2231 // Defines an AccessorInfo property on the given object. 2232 MUST_USE_RESULT static MaybeHandle<Object> SetAccessor( 2233 Handle<JSObject> object, 2234 Handle<AccessorInfo> info); 2235 2236 MUST_USE_RESULT static MaybeHandle<Object> GetPropertyWithInterceptor( 2237 Handle<JSObject> object, 2238 Handle<Object> receiver, 2239 Handle<Name> name); 2240 2241 // Returns true if this is an instance of an api function and has 2242 // been modified since it was created. May give false positives. 2243 bool IsDirty(); 2244 2245 // Accessors for hidden properties object. 2246 // 2247 // Hidden properties are not own properties of the object itself. 2248 // Instead they are stored in an auxiliary structure kept as an own 2249 // property with a special name Heap::hidden_string(). But if the 2250 // receiver is a JSGlobalProxy then the auxiliary object is a property 2251 // of its prototype, and if it's a detached proxy, then you can't have 2252 // hidden properties. 2253 2254 // Sets a hidden property on this object. Returns this object if successful, 2255 // undefined if called on a detached proxy. 2256 static Handle<Object> SetHiddenProperty(Handle<JSObject> object, 2257 Handle<Name> key, 2258 Handle<Object> value); 2259 // Gets the value of a hidden property with the given key. Returns the hole 2260 // if the property doesn't exist (or if called on a detached proxy), 2261 // otherwise returns the value set for the key. 2262 Object* GetHiddenProperty(Handle<Name> key); 2263 // Deletes a hidden property. Deleting a non-existing property is 2264 // considered successful. 2265 static void DeleteHiddenProperty(Handle<JSObject> object, 2266 Handle<Name> key); 2267 // Returns true if the object has a property with the hidden string as name. 2268 static bool HasHiddenProperties(Handle<JSObject> object); 2269 2270 static void SetIdentityHash(Handle<JSObject> object, Handle<Smi> hash); 2271 2272 static inline void ValidateElements(Handle<JSObject> object); 2273 2274 // Makes sure that this object can contain HeapObject as elements. 2275 static inline void EnsureCanContainHeapObjectElements(Handle<JSObject> obj); 2276 2277 // Makes sure that this object can contain the specified elements. 2278 static inline void EnsureCanContainElements( 2279 Handle<JSObject> object, 2280 Object** elements, 2281 uint32_t count, 2282 EnsureElementsMode mode); 2283 static inline void EnsureCanContainElements( 2284 Handle<JSObject> object, 2285 Handle<FixedArrayBase> elements, 2286 uint32_t length, 2287 EnsureElementsMode mode); 2288 static void EnsureCanContainElements( 2289 Handle<JSObject> object, 2290 Arguments* arguments, 2291 uint32_t first_arg, 2292 uint32_t arg_count, 2293 EnsureElementsMode mode); 2294 2295 // Would we convert a fast elements array to dictionary mode given 2296 // an access at key? 2297 bool WouldConvertToSlowElements(Handle<Object> key); 2298 // Do we want to keep the elements in fast case when increasing the 2299 // capacity? 2300 bool ShouldConvertToSlowElements(int new_capacity); 2301 // Returns true if the backing storage for the slow-case elements of 2302 // this object takes up nearly as much space as a fast-case backing 2303 // storage would. In that case the JSObject should have fast 2304 // elements. 2305 bool ShouldConvertToFastElements(); 2306 // Returns true if the elements of JSObject contains only values that can be 2307 // represented in a FixedDoubleArray and has at least one value that can only 2308 // be represented as a double and not a Smi. 2309 bool ShouldConvertToFastDoubleElements(bool* has_smi_only_elements); 2310 2311 // Computes the new capacity when expanding the elements of a JSObject. 2312 static int NewElementsCapacity(int old_capacity) { 2313 // (old_capacity + 50%) + 16 2314 return old_capacity + (old_capacity >> 1) + 16; 2315 } 2316 2317 // These methods do not perform access checks! 2318 MUST_USE_RESULT static MaybeHandle<AccessorPair> GetOwnPropertyAccessorPair( 2319 Handle<JSObject> object, 2320 Handle<Name> name); 2321 MUST_USE_RESULT static MaybeHandle<AccessorPair> GetOwnElementAccessorPair( 2322 Handle<JSObject> object, 2323 uint32_t index); 2324 2325 MUST_USE_RESULT static MaybeHandle<Object> SetFastElement( 2326 Handle<JSObject> object, 2327 uint32_t index, 2328 Handle<Object> value, 2329 StrictMode strict_mode, 2330 bool check_prototype); 2331 2332 MUST_USE_RESULT static MaybeHandle<Object> SetOwnElement( 2333 Handle<JSObject> object, 2334 uint32_t index, 2335 Handle<Object> value, 2336 StrictMode strict_mode); 2337 2338 // Empty handle is returned if the element cannot be set to the given value. 2339 MUST_USE_RESULT static MaybeHandle<Object> SetElement( 2340 Handle<JSObject> object, 2341 uint32_t index, 2342 Handle<Object> value, 2343 PropertyAttributes attributes, 2344 StrictMode strict_mode, 2345 bool check_prototype = true, 2346 SetPropertyMode set_mode = SET_PROPERTY); 2347 2348 // Returns the index'th element. 2349 // The undefined object if index is out of bounds. 2350 MUST_USE_RESULT static MaybeHandle<Object> GetElementWithInterceptor( 2351 Handle<JSObject> object, 2352 Handle<Object> receiver, 2353 uint32_t index); 2354 2355 enum SetFastElementsCapacitySmiMode { 2356 kAllowSmiElements, 2357 kForceSmiElements, 2358 kDontAllowSmiElements 2359 }; 2360 2361 // Replace the elements' backing store with fast elements of the given 2362 // capacity. Update the length for JSArrays. Returns the new backing 2363 // store. 2364 static Handle<FixedArray> SetFastElementsCapacityAndLength( 2365 Handle<JSObject> object, 2366 int capacity, 2367 int length, 2368 SetFastElementsCapacitySmiMode smi_mode); 2369 static void SetFastDoubleElementsCapacityAndLength( 2370 Handle<JSObject> object, 2371 int capacity, 2372 int length); 2373 2374 // Lookup interceptors are used for handling properties controlled by host 2375 // objects. 2376 inline bool HasNamedInterceptor(); 2377 inline bool HasIndexedInterceptor(); 2378 2379 // Computes the enumerable keys from interceptors. Used for debug mirrors and 2380 // by JSReceiver::GetKeys. 2381 MUST_USE_RESULT static MaybeHandle<JSObject> GetKeysForNamedInterceptor( 2382 Handle<JSObject> object, 2383 Handle<JSReceiver> receiver); 2384 MUST_USE_RESULT static MaybeHandle<JSObject> GetKeysForIndexedInterceptor( 2385 Handle<JSObject> object, 2386 Handle<JSReceiver> receiver); 2387 2388 // Support functions for v8 api (needed for correct interceptor behavior). 2389 static bool HasRealNamedProperty(Handle<JSObject> object, 2390 Handle<Name> key); 2391 static bool HasRealElementProperty(Handle<JSObject> object, uint32_t index); 2392 static bool HasRealNamedCallbackProperty(Handle<JSObject> object, 2393 Handle<Name> key); 2394 2395 // Get the header size for a JSObject. Used to compute the index of 2396 // internal fields as well as the number of internal fields. 2397 inline int GetHeaderSize(); 2398 2399 inline int GetInternalFieldCount(); 2400 inline int GetInternalFieldOffset(int index); 2401 inline Object* GetInternalField(int index); 2402 inline void SetInternalField(int index, Object* value); 2403 inline void SetInternalField(int index, Smi* value); 2404 2405 // The following lookup functions skip interceptors. 2406 void LookupOwnRealNamedProperty(Handle<Name> name, LookupResult* result); 2407 void LookupRealNamedProperty(Handle<Name> name, LookupResult* result); 2408 void LookupRealNamedPropertyInPrototypes(Handle<Name> name, 2409 LookupResult* result); 2410 2411 // Returns the number of properties on this object filtering out properties 2412 // with the specified attributes (ignoring interceptors). 2413 int NumberOfOwnProperties(PropertyAttributes filter = NONE); 2414 // Fill in details for properties into storage starting at the specified 2415 // index. 2416 void GetOwnPropertyNames( 2417 FixedArray* storage, int index, PropertyAttributes filter = NONE); 2418 2419 // Returns the number of properties on this object filtering out properties 2420 // with the specified attributes (ignoring interceptors). 2421 int NumberOfOwnElements(PropertyAttributes filter); 2422 // Returns the number of enumerable elements (ignoring interceptors). 2423 int NumberOfEnumElements(); 2424 // Returns the number of elements on this object filtering out elements 2425 // with the specified attributes (ignoring interceptors). 2426 int GetOwnElementKeys(FixedArray* storage, PropertyAttributes filter); 2427 // Count and fill in the enumerable elements into storage. 2428 // (storage->length() == NumberOfEnumElements()). 2429 // If storage is NULL, will count the elements without adding 2430 // them to any storage. 2431 // Returns the number of enumerable elements. 2432 int GetEnumElementKeys(FixedArray* storage); 2433 2434 // Returns a new map with all transitions dropped from the object's current 2435 // map and the ElementsKind set. 2436 static Handle<Map> GetElementsTransitionMap(Handle<JSObject> object, 2437 ElementsKind to_kind); 2438 static void TransitionElementsKind(Handle<JSObject> object, 2439 ElementsKind to_kind); 2440 2441 // TODO(mstarzinger): Both public because of ConvertAndSetOwnProperty(). 2442 static void MigrateToMap(Handle<JSObject> object, Handle<Map> new_map); 2443 static void GeneralizeFieldRepresentation(Handle<JSObject> object, 2444 int modify_index, 2445 Representation new_representation, 2446 Handle<HeapType> new_field_type, 2447 StoreMode store_mode); 2448 2449 // Convert the object to use the canonical dictionary 2450 // representation. If the object is expected to have additional properties 2451 // added this number can be indicated to have the backing store allocated to 2452 // an initial capacity for holding these properties. 2453 static void NormalizeProperties(Handle<JSObject> object, 2454 PropertyNormalizationMode mode, 2455 int expected_additional_properties); 2456 2457 // Convert and update the elements backing store to be a 2458 // SeededNumberDictionary dictionary. Returns the backing after conversion. 2459 static Handle<SeededNumberDictionary> NormalizeElements( 2460 Handle<JSObject> object); 2461 2462 // Transform slow named properties to fast variants. 2463 static void TransformToFastProperties(Handle<JSObject> object, 2464 int unused_property_fields); 2465 2466 // Access fast-case object properties at index. 2467 static Handle<Object> FastPropertyAt(Handle<JSObject> object, 2468 Representation representation, 2469 FieldIndex index); 2470 inline Object* RawFastPropertyAt(FieldIndex index); 2471 inline void FastPropertyAtPut(FieldIndex index, Object* value); 2472 void WriteToField(int descriptor, Object* value); 2473 2474 // Access to in object properties. 2475 inline int GetInObjectPropertyOffset(int index); 2476 inline Object* InObjectPropertyAt(int index); 2477 inline Object* InObjectPropertyAtPut(int index, 2478 Object* value, 2479 WriteBarrierMode mode 2480 = UPDATE_WRITE_BARRIER); 2481 2482 // Set the object's prototype (only JSReceiver and null are allowed values). 2483 MUST_USE_RESULT static MaybeHandle<Object> SetPrototype( 2484 Handle<JSObject> object, 2485 Handle<Object> value, 2486 bool skip_hidden_prototypes = false); 2487 2488 // Initializes the body after properties slot, properties slot is 2489 // initialized by set_properties. Fill the pre-allocated fields with 2490 // pre_allocated_value and the rest with filler_value. 2491 // Note: this call does not update write barrier, the caller is responsible 2492 // to ensure that |filler_value| can be collected without WB here. 2493 inline void InitializeBody(Map* map, 2494 Object* pre_allocated_value, 2495 Object* filler_value); 2496 2497 // Check whether this object references another object 2498 bool ReferencesObject(Object* obj); 2499 2500 // Disalow further properties to be added to the object. 2501 MUST_USE_RESULT static MaybeHandle<Object> PreventExtensions( 2502 Handle<JSObject> object); 2503 2504 // ES5 Object.freeze 2505 MUST_USE_RESULT static MaybeHandle<Object> Freeze(Handle<JSObject> object); 2506 2507 // Called the first time an object is observed with ES7 Object.observe. 2508 static void SetObserved(Handle<JSObject> object); 2509 2510 // Copy object. 2511 enum DeepCopyHints { 2512 kNoHints = 0, 2513 kObjectIsShallowArray = 1 2514 }; 2515 2516 static Handle<JSObject> Copy(Handle<JSObject> object); 2517 MUST_USE_RESULT static MaybeHandle<JSObject> DeepCopy( 2518 Handle<JSObject> object, 2519 AllocationSiteUsageContext* site_context, 2520 DeepCopyHints hints = kNoHints); 2521 MUST_USE_RESULT static MaybeHandle<JSObject> DeepWalk( 2522 Handle<JSObject> object, 2523 AllocationSiteCreationContext* site_context); 2524 2525 static Handle<Object> GetDataProperty(Handle<JSObject> object, 2526 Handle<Name> key); 2527 2528 // Casting. 2529 static inline JSObject* cast(Object* obj); 2530 2531 // Dispatched behavior. 2532 void JSObjectShortPrint(StringStream* accumulator); 2533 DECLARE_PRINTER(JSObject) 2534 DECLARE_VERIFIER(JSObject) 2535 #ifdef OBJECT_PRINT 2536 void PrintProperties(FILE* out = stdout); 2537 void PrintElements(FILE* out = stdout); 2538 void PrintTransitions(FILE* out = stdout); 2539 #endif 2540 2541 static void PrintElementsTransition( 2542 FILE* file, Handle<JSObject> object, 2543 ElementsKind from_kind, Handle<FixedArrayBase> from_elements, 2544 ElementsKind to_kind, Handle<FixedArrayBase> to_elements); 2545 2546 void PrintInstanceMigration(FILE* file, Map* original_map, Map* new_map); 2547 2548 #ifdef DEBUG 2549 // Structure for collecting spill information about JSObjects. 2550 class SpillInformation { 2551 public: 2552 void Clear(); 2553 void Print(); 2554 int number_of_objects_; 2555 int number_of_objects_with_fast_properties_; 2556 int number_of_objects_with_fast_elements_; 2557 int number_of_fast_used_fields_; 2558 int number_of_fast_unused_fields_; 2559 int number_of_slow_used_properties_; 2560 int number_of_slow_unused_properties_; 2561 int number_of_fast_used_elements_; 2562 int number_of_fast_unused_elements_; 2563 int number_of_slow_used_elements_; 2564 int number_of_slow_unused_elements_; 2565 }; 2566 2567 void IncrementSpillStatistics(SpillInformation* info); 2568 #endif 2569 2570 #ifdef VERIFY_HEAP 2571 // If a GC was caused while constructing this object, the elements pointer 2572 // may point to a one pointer filler map. The object won't be rooted, but 2573 // our heap verification code could stumble across it. 2574 bool ElementsAreSafeToExamine(); 2575 #endif 2576 2577 Object* SlowReverseLookup(Object* value); 2578 2579 // Maximal number of fast properties for the JSObject. Used to 2580 // restrict the number of map transitions to avoid an explosion in 2581 // the number of maps for objects used as dictionaries. 2582 inline bool TooManyFastProperties( 2583 StoreFromKeyed store_mode = MAY_BE_STORE_FROM_KEYED); 2584 2585 // Maximal number of elements (numbered 0 .. kMaxElementCount - 1). 2586 // Also maximal value of JSArray's length property. 2587 static const uint32_t kMaxElementCount = 0xffffffffu; 2588 2589 // Constants for heuristics controlling conversion of fast elements 2590 // to slow elements. 2591 2592 // Maximal gap that can be introduced by adding an element beyond 2593 // the current elements length. 2594 static const uint32_t kMaxGap = 1024; 2595 2596 // Maximal length of fast elements array that won't be checked for 2597 // being dense enough on expansion. 2598 static const int kMaxUncheckedFastElementsLength = 5000; 2599 2600 // Same as above but for old arrays. This limit is more strict. We 2601 // don't want to be wasteful with long lived objects. 2602 static const int kMaxUncheckedOldFastElementsLength = 500; 2603 2604 // Note that Page::kMaxRegularHeapObjectSize puts a limit on 2605 // permissible values (see the ASSERT in heap.cc). 2606 static const int kInitialMaxFastElementArray = 100000; 2607 2608 // This constant applies only to the initial map of "$Object" aka 2609 // "global.Object" and not to arbitrary other JSObject maps. 2610 static const int kInitialGlobalObjectUnusedPropertiesCount = 4; 2611 2612 static const int kFastPropertiesSoftLimit = 12; 2613 static const int kMaxFastProperties = 128; 2614 static const int kMaxInstanceSize = 255 * kPointerSize; 2615 // When extending the backing storage for property values, we increase 2616 // its size by more than the 1 entry necessary, so sequentially adding fields 2617 // to the same object requires fewer allocations and copies. 2618 static const int kFieldsAdded = 3; 2619 2620 // Layout description. 2621 static const int kPropertiesOffset = HeapObject::kHeaderSize; 2622 static const int kElementsOffset = kPropertiesOffset + kPointerSize; 2623 static const int kHeaderSize = kElementsOffset + kPointerSize; 2624 2625 STATIC_ASSERT(kHeaderSize == Internals::kJSObjectHeaderSize); 2626 2627 class BodyDescriptor : public FlexibleBodyDescriptor<kPropertiesOffset> { 2628 public: 2629 static inline int SizeOf(Map* map, HeapObject* object); 2630 }; 2631 2632 Context* GetCreationContext(); 2633 2634 // Enqueue change record for Object.observe. May cause GC. 2635 static void EnqueueChangeRecord(Handle<JSObject> object, 2636 const char* type, 2637 Handle<Name> name, 2638 Handle<Object> old_value); 2639 2640 private: 2641 friend class DictionaryElementsAccessor; 2642 friend class JSReceiver; 2643 friend class Object; 2644 2645 static void UpdateAllocationSite(Handle<JSObject> object, 2646 ElementsKind to_kind); 2647 2648 // Used from Object::GetProperty(). 2649 MUST_USE_RESULT static MaybeHandle<Object> GetPropertyWithFailedAccessCheck( 2650 LookupIterator* it); 2651 2652 MUST_USE_RESULT static MaybeHandle<Object> GetElementWithCallback( 2653 Handle<JSObject> object, 2654 Handle<Object> receiver, 2655 Handle<Object> structure, 2656 uint32_t index, 2657 Handle<Object> holder); 2658 2659 static PropertyAttributes GetElementAttributeWithInterceptor( 2660 Handle<JSObject> object, 2661 Handle<JSReceiver> receiver, 2662 uint32_t index, 2663 bool continue_search); 2664 static PropertyAttributes GetElementAttributeWithoutInterceptor( 2665 Handle<JSObject> object, 2666 Handle<JSReceiver> receiver, 2667 uint32_t index, 2668 bool continue_search); 2669 MUST_USE_RESULT static MaybeHandle<Object> SetElementWithCallback( 2670 Handle<JSObject> object, 2671 Handle<Object> structure, 2672 uint32_t index, 2673 Handle<Object> value, 2674 Handle<JSObject> holder, 2675 StrictMode strict_mode); 2676 MUST_USE_RESULT static MaybeHandle<Object> SetElementWithInterceptor( 2677 Handle<JSObject> object, 2678 uint32_t index, 2679 Handle<Object> value, 2680 PropertyAttributes attributes, 2681 StrictMode strict_mode, 2682 bool check_prototype, 2683 SetPropertyMode set_mode); 2684 MUST_USE_RESULT static MaybeHandle<Object> SetElementWithoutInterceptor( 2685 Handle<JSObject> object, 2686 uint32_t index, 2687 Handle<Object> value, 2688 PropertyAttributes attributes, 2689 StrictMode strict_mode, 2690 bool check_prototype, 2691 SetPropertyMode set_mode); 2692 MUST_USE_RESULT 2693 static MaybeHandle<Object> SetElementWithCallbackSetterInPrototypes( 2694 Handle<JSObject> object, 2695 uint32_t index, 2696 Handle<Object> value, 2697 bool* found, 2698 StrictMode strict_mode); 2699 MUST_USE_RESULT static MaybeHandle<Object> SetDictionaryElement( 2700 Handle<JSObject> object, 2701 uint32_t index, 2702 Handle<Object> value, 2703 PropertyAttributes attributes, 2704 StrictMode strict_mode, 2705 bool check_prototype, 2706 SetPropertyMode set_mode = SET_PROPERTY); 2707 MUST_USE_RESULT static MaybeHandle<Object> SetFastDoubleElement( 2708 Handle<JSObject> object, 2709 uint32_t index, 2710 Handle<Object> value, 2711 StrictMode strict_mode, 2712 bool check_prototype = true); 2713 2714 // Searches the prototype chain for property 'name'. If it is found and 2715 // has a setter, invoke it and set '*done' to true. If it is found and is 2716 // read-only, reject and set '*done' to true. Otherwise, set '*done' to 2717 // false. Can throw and return an empty handle with '*done==true'. 2718 MUST_USE_RESULT static MaybeHandle<Object> SetPropertyViaPrototypes( 2719 Handle<JSObject> object, 2720 Handle<Name> name, 2721 Handle<Object> value, 2722 PropertyAttributes attributes, 2723 StrictMode strict_mode, 2724 bool* done); 2725 MUST_USE_RESULT static MaybeHandle<Object> SetPropertyPostInterceptor( 2726 Handle<JSObject> object, 2727 Handle<Name> name, 2728 Handle<Object> value, 2729 PropertyAttributes attributes, 2730 StrictMode strict_mode); 2731 MUST_USE_RESULT static MaybeHandle<Object> SetPropertyUsingTransition( 2732 Handle<JSObject> object, 2733 LookupResult* lookup, 2734 Handle<Name> name, 2735 Handle<Object> value, 2736 PropertyAttributes attributes); 2737 MUST_USE_RESULT static MaybeHandle<Object> SetPropertyWithFailedAccessCheck( 2738 Handle<JSObject> object, 2739 LookupResult* result, 2740 Handle<Name> name, 2741 Handle<Object> value, 2742 bool check_prototype, 2743 StrictMode strict_mode); 2744 2745 // Add a property to an object. 2746 MUST_USE_RESULT static MaybeHandle<Object> AddProperty( 2747 Handle<JSObject> object, 2748 Handle<Name> name, 2749 Handle<Object> value, 2750 PropertyAttributes attributes, 2751 StrictMode strict_mode, 2752 StoreFromKeyed store_mode = MAY_BE_STORE_FROM_KEYED, 2753 ExtensibilityCheck extensibility_check = PERFORM_EXTENSIBILITY_CHECK, 2754 ValueType value_type = OPTIMAL_REPRESENTATION, 2755 StoreMode mode = ALLOW_AS_CONSTANT, 2756 TransitionFlag flag = INSERT_TRANSITION); 2757 2758 // Add a property to a fast-case object. 2759 static void AddFastProperty(Handle<JSObject> object, 2760 Handle<Name> name, 2761 Handle<Object> value, 2762 PropertyAttributes attributes, 2763 StoreFromKeyed store_mode, 2764 ValueType value_type, 2765 TransitionFlag flag); 2766 2767 static void MigrateToNewProperty(Handle<JSObject> object, 2768 Handle<Map> transition, 2769 Handle<Object> value); 2770 2771 // Add a property to a slow-case object. 2772 static void AddSlowProperty(Handle<JSObject> object, 2773 Handle<Name> name, 2774 Handle<Object> value, 2775 PropertyAttributes attributes); 2776 2777 MUST_USE_RESULT static MaybeHandle<Object> DeleteProperty( 2778 Handle<JSObject> object, 2779 Handle<Name> name, 2780 DeleteMode mode); 2781 static Handle<Object> DeletePropertyPostInterceptor(Handle<JSObject> object, 2782 Handle<Name> name, 2783 DeleteMode mode); 2784 MUST_USE_RESULT static MaybeHandle<Object> DeletePropertyWithInterceptor( 2785 Handle<JSObject> object, 2786 Handle<Name> name); 2787 2788 // Deletes the named property in a normalized object. 2789 static Handle<Object> DeleteNormalizedProperty(Handle<JSObject> object, 2790 Handle<Name> name, 2791 DeleteMode mode); 2792 2793 MUST_USE_RESULT static MaybeHandle<Object> DeleteElement( 2794 Handle<JSObject> object, 2795 uint32_t index, 2796 DeleteMode mode); 2797 MUST_USE_RESULT static MaybeHandle<Object> DeleteElementWithInterceptor( 2798 Handle<JSObject> object, 2799 uint32_t index); 2800 2801 bool ReferencesObjectFromElements(FixedArray* elements, 2802 ElementsKind kind, 2803 Object* object); 2804 2805 // Returns true if most of the elements backing storage is used. 2806 bool HasDenseElements(); 2807 2808 // Gets the current elements capacity and the number of used elements. 2809 void GetElementsCapacityAndUsage(int* capacity, int* used); 2810 2811 static bool CanSetCallback(Handle<JSObject> object, Handle<Name> name); 2812 static void SetElementCallback(Handle<JSObject> object, 2813 uint32_t index, 2814 Handle<Object> structure, 2815 PropertyAttributes attributes); 2816 static void SetPropertyCallback(Handle<JSObject> object, 2817 Handle<Name> name, 2818 Handle<Object> structure, 2819 PropertyAttributes attributes); 2820 static void DefineElementAccessor(Handle<JSObject> object, 2821 uint32_t index, 2822 Handle<Object> getter, 2823 Handle<Object> setter, 2824 PropertyAttributes attributes, 2825 v8::AccessControl access_control); 2826 static Handle<AccessorPair> CreateAccessorPairFor(Handle<JSObject> object, 2827 Handle<Name> name); 2828 static void DefinePropertyAccessor(Handle<JSObject> object, 2829 Handle<Name> name, 2830 Handle<Object> getter, 2831 Handle<Object> setter, 2832 PropertyAttributes attributes, 2833 v8::AccessControl access_control); 2834 2835 // Try to define a single accessor paying attention to map transitions. 2836 // Returns false if this was not possible and we have to use the slow case. 2837 static bool DefineFastAccessor(Handle<JSObject> object, 2838 Handle<Name> name, 2839 AccessorComponent component, 2840 Handle<Object> accessor, 2841 PropertyAttributes attributes); 2842 2843 2844 // Return the hash table backing store or the inline stored identity hash, 2845 // whatever is found. 2846 MUST_USE_RESULT Object* GetHiddenPropertiesHashTable(); 2847 2848 // Return the hash table backing store for hidden properties. If there is no 2849 // backing store, allocate one. 2850 static Handle<ObjectHashTable> GetOrCreateHiddenPropertiesHashtable( 2851 Handle<JSObject> object); 2852 2853 // Set the hidden property backing store to either a hash table or 2854 // the inline-stored identity hash. 2855 static Handle<Object> SetHiddenPropertiesHashTable( 2856 Handle<JSObject> object, 2857 Handle<Object> value); 2858 2859 MUST_USE_RESULT Object* GetIdentityHash(); 2860 2861 static Handle<Smi> GetOrCreateIdentityHash(Handle<JSObject> object); 2862 2863 DISALLOW_IMPLICIT_CONSTRUCTORS(JSObject); 2864 }; 2865 2866 2867 // Common superclass for FixedArrays that allow implementations to share 2868 // common accessors and some code paths. 2869 class FixedArrayBase: public HeapObject { 2870 public: 2871 // [length]: length of the array. 2872 inline int length(); 2873 inline void set_length(int value); 2874 2875 // Get and set the length using acquire loads and release stores. 2876 inline int synchronized_length(); 2877 inline void synchronized_set_length(int value); 2878 2879 inline static FixedArrayBase* cast(Object* object); 2880 2881 // Layout description. 2882 // Length is smi tagged when it is stored. 2883 static const int kLengthOffset = HeapObject::kHeaderSize; 2884 static const int kHeaderSize = kLengthOffset + kPointerSize; 2885 }; 2886 2887 2888 class FixedDoubleArray; 2889 class IncrementalMarking; 2890 2891 2892 // FixedArray describes fixed-sized arrays with element type Object*. 2893 class FixedArray: public FixedArrayBase { 2894 public: 2895 // Setter and getter for elements. 2896 inline Object* get(int index); 2897 static inline Handle<Object> get(Handle<FixedArray> array, int index); 2898 // Setter that uses write barrier. 2899 inline void set(int index, Object* value); 2900 inline bool is_the_hole(int index); 2901 2902 // Setter that doesn't need write barrier. 2903 inline void set(int index, Smi* value); 2904 // Setter with explicit barrier mode. 2905 inline void set(int index, Object* value, WriteBarrierMode mode); 2906 2907 // Setters for frequently used oddballs located in old space. 2908 inline void set_undefined(int index); 2909 inline void set_null(int index); 2910 inline void set_the_hole(int index); 2911 2912 inline Object** GetFirstElementAddress(); 2913 inline bool ContainsOnlySmisOrHoles(); 2914 2915 // Gives access to raw memory which stores the array's data. 2916 inline Object** data_start(); 2917 2918 inline void FillWithHoles(int from, int to); 2919 2920 // Shrink length and insert filler objects. 2921 void Shrink(int length); 2922 2923 // Copy operation. 2924 static Handle<FixedArray> CopySize(Handle<FixedArray> array, 2925 int new_length, 2926 PretenureFlag pretenure = NOT_TENURED); 2927 2928 // Add the elements of a JSArray to this FixedArray. 2929 MUST_USE_RESULT static MaybeHandle<FixedArray> AddKeysFromArrayLike( 2930 Handle<FixedArray> content, 2931 Handle<JSObject> array); 2932 2933 // Computes the union of keys and return the result. 2934 // Used for implementing "for (n in object) { }" 2935 MUST_USE_RESULT static MaybeHandle<FixedArray> UnionOfKeys( 2936 Handle<FixedArray> first, 2937 Handle<FixedArray> second); 2938 2939 // Copy a sub array from the receiver to dest. 2940 void CopyTo(int pos, FixedArray* dest, int dest_pos, int len); 2941 2942 // Garbage collection support. 2943 static int SizeFor(int length) { return kHeaderSize + length * kPointerSize; } 2944 2945 // Code Generation support. 2946 static int OffsetOfElementAt(int index) { return SizeFor(index); } 2947 2948 // Garbage collection support. 2949 Object** RawFieldOfElementAt(int index) { 2950 return HeapObject::RawField(this, OffsetOfElementAt(index)); 2951 } 2952 2953 // Casting. 2954 static inline FixedArray* cast(Object* obj); 2955 2956 // Maximal allowed size, in bytes, of a single FixedArray. 2957 // Prevents overflowing size computations, as well as extreme memory 2958 // consumption. 2959 static const int kMaxSize = 128 * MB * kPointerSize; 2960 // Maximally allowed length of a FixedArray. 2961 static const int kMaxLength = (kMaxSize - kHeaderSize) / kPointerSize; 2962 2963 // Dispatched behavior. 2964 DECLARE_PRINTER(FixedArray) 2965 DECLARE_VERIFIER(FixedArray) 2966 #ifdef DEBUG 2967 // Checks if two FixedArrays have identical contents. 2968 bool IsEqualTo(FixedArray* other); 2969 #endif 2970 2971 // Swap two elements in a pair of arrays. If this array and the 2972 // numbers array are the same object, the elements are only swapped 2973 // once. 2974 void SwapPairs(FixedArray* numbers, int i, int j); 2975 2976 // Sort prefix of this array and the numbers array as pairs wrt. the 2977 // numbers. If the numbers array and the this array are the same 2978 // object, the prefix of this array is sorted. 2979 void SortPairs(FixedArray* numbers, uint32_t len); 2980 2981 class BodyDescriptor : public FlexibleBodyDescriptor<kHeaderSize> { 2982 public: 2983 static inline int SizeOf(Map* map, HeapObject* object) { 2984 return SizeFor(reinterpret_cast<FixedArray*>(object)->length()); 2985 } 2986 }; 2987 2988 protected: 2989 // Set operation on FixedArray without using write barriers. Can 2990 // only be used for storing old space objects or smis. 2991 static inline void NoWriteBarrierSet(FixedArray* array, 2992 int index, 2993 Object* value); 2994 2995 // Set operation on FixedArray without incremental write barrier. Can 2996 // only be used if the object is guaranteed to be white (whiteness witness 2997 // is present). 2998 static inline void NoIncrementalWriteBarrierSet(FixedArray* array, 2999 int index, 3000 Object* value); 3001 3002 private: 3003 STATIC_ASSERT(kHeaderSize == Internals::kFixedArrayHeaderSize); 3004 3005 DISALLOW_IMPLICIT_CONSTRUCTORS(FixedArray); 3006 }; 3007 3008 3009 // FixedDoubleArray describes fixed-sized arrays with element type double. 3010 class FixedDoubleArray: public FixedArrayBase { 3011 public: 3012 // Setter and getter for elements. 3013 inline double get_scalar(int index); 3014 inline int64_t get_representation(int index); 3015 static inline Handle<Object> get(Handle<FixedDoubleArray> array, int index); 3016 inline void set(int index, double value); 3017 inline void set_the_hole(int index); 3018 3019 // Checking for the hole. 3020 inline bool is_the_hole(int index); 3021 3022 // Garbage collection support. 3023 inline static int SizeFor(int length) { 3024 return kHeaderSize + length * kDoubleSize; 3025 } 3026 3027 // Gives access to raw memory which stores the array's data. 3028 inline double* data_start(); 3029 3030 inline void FillWithHoles(int from, int to); 3031 3032 // Code Generation support. 3033 static int OffsetOfElementAt(int index) { return SizeFor(index); } 3034 3035 inline static bool is_the_hole_nan(double value); 3036 inline static double hole_nan_as_double(); 3037 inline static double canonical_not_the_hole_nan_as_double(); 3038 3039 // Casting. 3040 static inline FixedDoubleArray* cast(Object* obj); 3041 3042 // Maximal allowed size, in bytes, of a single FixedDoubleArray. 3043 // Prevents overflowing size computations, as well as extreme memory 3044 // consumption. 3045 static const int kMaxSize = 512 * MB; 3046 // Maximally allowed length of a FixedArray. 3047 static const int kMaxLength = (kMaxSize - kHeaderSize) / kDoubleSize; 3048 3049 // Dispatched behavior. 3050 DECLARE_PRINTER(FixedDoubleArray) 3051 DECLARE_VERIFIER(FixedDoubleArray) 3052 3053 private: 3054 DISALLOW_IMPLICIT_CONSTRUCTORS(FixedDoubleArray); 3055 }; 3056 3057 3058 // ConstantPoolArray describes a fixed-sized array containing constant pool 3059 // entries. 3060 // 3061 // A ConstantPoolArray can be structured in two different ways depending upon 3062 // whether it is extended or small. The is_extended_layout() method can be used 3063 // to discover which layout the constant pool has. 3064 // 3065 // The format of a small constant pool is: 3066 // [kSmallLayout1Offset] : Small section layout bitmap 1 3067 // [kSmallLayout2Offset] : Small section layout bitmap 2 3068 // [first_index(INT64, SMALL_SECTION)] : 64 bit entries 3069 // ... : ... 3070 // [first_index(CODE_PTR, SMALL_SECTION)] : code pointer entries 3071 // ... : ... 3072 // [first_index(HEAP_PTR, SMALL_SECTION)] : heap pointer entries 3073 // ... : ... 3074 // [first_index(INT32, SMALL_SECTION)] : 32 bit entries 3075 // ... : ... 3076 // 3077 // If the constant pool has an extended layout, the extended section constant 3078 // pool also contains an extended section, which has the following format at 3079 // location get_extended_section_header_offset(): 3080 // [kExtendedInt64CountOffset] : count of extended 64 bit entries 3081 // [kExtendedCodePtrCountOffset] : count of extended code pointers 3082 // [kExtendedHeapPtrCountOffset] : count of extended heap pointers 3083 // [kExtendedInt32CountOffset] : count of extended 32 bit entries 3084 // [first_index(INT64, EXTENDED_SECTION)] : 64 bit entries 3085 // ... : ... 3086 // [first_index(CODE_PTR, EXTENDED_SECTION)]: code pointer entries 3087 // ... : ... 3088 // [first_index(HEAP_PTR, EXTENDED_SECTION)]: heap pointer entries 3089 // ... : ... 3090 // [first_index(INT32, EXTENDED_SECTION)] : 32 bit entries 3091 // ... : ... 3092 // 3093 class ConstantPoolArray: public HeapObject { 3094 public: 3095 enum WeakObjectState { 3096 NO_WEAK_OBJECTS, 3097 WEAK_OBJECTS_IN_OPTIMIZED_CODE, 3098 WEAK_OBJECTS_IN_IC 3099 }; 3100 3101 enum Type { 3102 INT64 = 0, 3103 CODE_PTR, 3104 HEAP_PTR, 3105 INT32, 3106 // Number of types stored by the ConstantPoolArrays. 3107 NUMBER_OF_TYPES, 3108 FIRST_TYPE = INT64, 3109 LAST_TYPE = INT32 3110 }; 3111 3112 enum LayoutSection { 3113 SMALL_SECTION = 0, 3114 EXTENDED_SECTION 3115 }; 3116 3117 class NumberOfEntries BASE_EMBEDDED { 3118 public: 3119 inline NumberOfEntries(int int64_count, int code_ptr_count, 3120 int heap_ptr_count, int int32_count) { 3121 element_counts_[INT64] = int64_count; 3122 element_counts_[CODE_PTR] = code_ptr_count; 3123 element_counts_[HEAP_PTR] = heap_ptr_count; 3124 element_counts_[INT32] = int32_count; 3125 } 3126 3127 inline NumberOfEntries(ConstantPoolArray* array, LayoutSection section) { 3128 element_counts_[INT64] = array->number_of_entries(INT64, section); 3129 element_counts_[CODE_PTR] = array->number_of_entries(CODE_PTR, section); 3130 element_counts_[HEAP_PTR] = array->number_of_entries(HEAP_PTR, section); 3131 element_counts_[INT32] = array->number_of_entries(INT32, section); 3132 } 3133 3134 inline int count_of(Type type) const { 3135 ASSERT(type < NUMBER_OF_TYPES); 3136 return element_counts_[type]; 3137 } 3138 3139 inline int total_count() const { 3140 int count = 0; 3141 for (int i = 0; i < NUMBER_OF_TYPES; i++) { 3142 count += element_counts_[i]; 3143 } 3144 return count; 3145 } 3146 3147 inline int are_in_range(int min, int max) const { 3148 for (int i = FIRST_TYPE; i < NUMBER_OF_TYPES; i++) { 3149 if (element_counts_[i] < min || element_counts_[i] > max) { 3150 return false; 3151 } 3152 } 3153 return true; 3154 } 3155 3156 private: 3157 int element_counts_[NUMBER_OF_TYPES]; 3158 }; 3159 3160 class Iterator BASE_EMBEDDED { 3161 public: 3162 inline Iterator(ConstantPoolArray* array, Type type) 3163 : array_(array), type_(type), final_section_(array->final_section()) { 3164 current_section_ = SMALL_SECTION; 3165 next_index_ = array->first_index(type, SMALL_SECTION); 3166 update_section(); 3167 } 3168 3169 inline int next_index(); 3170 inline bool is_finished(); 3171 private: 3172 inline void update_section(); 3173 ConstantPoolArray* array_; 3174 const Type type_; 3175 const LayoutSection final_section_; 3176 3177 LayoutSection current_section_; 3178 int next_index_; 3179 }; 3180 3181 // Getters for the first index, the last index and the count of entries of 3182 // a given type for a given layout section. 3183 inline int first_index(Type type, LayoutSection layout_section); 3184 inline int last_index(Type type, LayoutSection layout_section); 3185 inline int number_of_entries(Type type, LayoutSection layout_section); 3186 3187 // Returns the type of the entry at the given index. 3188 inline Type get_type(int index); 3189 3190 // Setter and getter for pool elements. 3191 inline Address get_code_ptr_entry(int index); 3192 inline Object* get_heap_ptr_entry(int index); 3193 inline int64_t get_int64_entry(int index); 3194 inline int32_t get_int32_entry(int index); 3195 inline double get_int64_entry_as_double(int index); 3196 3197 inline void set(int index, Address value); 3198 inline void set(int index, Object* value); 3199 inline void set(int index, int64_t value); 3200 inline void set(int index, double value); 3201 inline void set(int index, int32_t value); 3202 3203 // Setter and getter for weak objects state 3204 inline void set_weak_object_state(WeakObjectState state); 3205 inline WeakObjectState get_weak_object_state(); 3206 3207 // Returns true if the constant pool has an extended layout, false if it has 3208 // only the small layout. 3209 inline bool is_extended_layout(); 3210 3211 // Returns the last LayoutSection in this constant pool array. 3212 inline LayoutSection final_section(); 3213 3214 // Set up initial state for a small layout constant pool array. 3215 inline void Init(const NumberOfEntries& small); 3216 3217 // Set up initial state for an extended layout constant pool array. 3218 inline void InitExtended(const NumberOfEntries& small, 3219 const NumberOfEntries& extended); 3220 3221 // Clears the pointer entries with GC safe values. 3222 void ClearPtrEntries(Isolate* isolate); 3223 3224 // returns the total number of entries in the constant pool array. 3225 inline int length(); 3226 3227 // Garbage collection support. 3228 inline int size(); 3229 3230 inline static int SizeFor(const NumberOfEntries& small) { 3231 int size = kFirstEntryOffset + 3232 (small.count_of(INT64) * kInt64Size) + 3233 (small.count_of(CODE_PTR) * kPointerSize) + 3234 (small.count_of(HEAP_PTR) * kPointerSize) + 3235 (small.count_of(INT32) * kInt32Size); 3236 return RoundUp(size, kPointerSize); 3237 } 3238 3239 inline static int SizeForExtended(const NumberOfEntries& small, 3240 const NumberOfEntries& extended) { 3241 int size = SizeFor(small); 3242 size = RoundUp(size, kInt64Size); // Align extended header to 64 bits. 3243 size += kExtendedFirstOffset + 3244 (extended.count_of(INT64) * kInt64Size) + 3245 (extended.count_of(CODE_PTR) * kPointerSize) + 3246 (extended.count_of(HEAP_PTR) * kPointerSize) + 3247 (extended.count_of(INT32) * kInt32Size); 3248 return RoundUp(size, kPointerSize); 3249 } 3250 3251 inline static int entry_size(Type type) { 3252 switch (type) { 3253 case INT32: 3254 return kInt32Size; 3255 case INT64: 3256 return kInt64Size; 3257 case CODE_PTR: 3258 case HEAP_PTR: 3259 return kPointerSize; 3260 default: 3261 UNREACHABLE(); 3262 return 0; 3263 } 3264 } 3265 3266 // Code Generation support. 3267 inline int OffsetOfElementAt(int index) { 3268 int offset; 3269 LayoutSection section; 3270 if (is_extended_layout() && index >= first_extended_section_index()) { 3271 section = EXTENDED_SECTION; 3272 offset = get_extended_section_header_offset() + kExtendedFirstOffset; 3273 } else { 3274 section = SMALL_SECTION; 3275 offset = kFirstEntryOffset; 3276 } 3277 3278 // Add offsets for the preceding type sections. 3279 ASSERT(index <= last_index(LAST_TYPE, section)); 3280 for (Type type = FIRST_TYPE; index > last_index(type, section); 3281 type = next_type(type)) { 3282 offset += entry_size(type) * number_of_entries(type, section); 3283 } 3284 3285 // Add offset for the index in it's type. 3286 Type type = get_type(index); 3287 offset += entry_size(type) * (index - first_index(type, section)); 3288 return offset; 3289 } 3290 3291 // Casting. 3292 static inline ConstantPoolArray* cast(Object* obj); 3293 3294 // Garbage collection support. 3295 Object** RawFieldOfElementAt(int index) { 3296 return HeapObject::RawField(this, OffsetOfElementAt(index)); 3297 } 3298 3299 // Small Layout description. 3300 static const int kSmallLayout1Offset = HeapObject::kHeaderSize; 3301 static const int kSmallLayout2Offset = kSmallLayout1Offset + kInt32Size; 3302 static const int kHeaderSize = kSmallLayout2Offset + kInt32Size; 3303 static const int kFirstEntryOffset = ROUND_UP(kHeaderSize, kInt64Size); 3304 3305 static const int kSmallLayoutCountBits = 10; 3306 static const int kMaxSmallEntriesPerType = (1 << kSmallLayoutCountBits) - 1; 3307 3308 // Fields in kSmallLayout1Offset. 3309 class Int64CountField: public BitField<int, 1, kSmallLayoutCountBits> {}; 3310 class CodePtrCountField: public BitField<int, 11, kSmallLayoutCountBits> {}; 3311 class HeapPtrCountField: public BitField<int, 21, kSmallLayoutCountBits> {}; 3312 class IsExtendedField: public BitField<bool, 31, 1> {}; 3313 3314 // Fields in kSmallLayout2Offset. 3315 class Int32CountField: public BitField<int, 1, kSmallLayoutCountBits> {}; 3316 class TotalCountField: public BitField<int, 11, 12> {}; 3317 class WeakObjectStateField: public BitField<WeakObjectState, 23, 2> {}; 3318 3319 // Extended layout description, which starts at 3320 // get_extended_section_header_offset(). 3321 static const int kExtendedInt64CountOffset = 0; 3322 static const int kExtendedCodePtrCountOffset = 3323 kExtendedInt64CountOffset + kPointerSize; 3324 static const int kExtendedHeapPtrCountOffset = 3325 kExtendedCodePtrCountOffset + kPointerSize; 3326 static const int kExtendedInt32CountOffset = 3327 kExtendedHeapPtrCountOffset + kPointerSize; 3328 static const int kExtendedFirstOffset = 3329 kExtendedInt32CountOffset + kPointerSize; 3330 3331 // Dispatched behavior. 3332 void ConstantPoolIterateBody(ObjectVisitor* v); 3333 3334 DECLARE_PRINTER(ConstantPoolArray) 3335 DECLARE_VERIFIER(ConstantPoolArray) 3336 3337 private: 3338 inline int first_extended_section_index(); 3339 inline int get_extended_section_header_offset(); 3340 3341 inline static Type next_type(Type type) { 3342 ASSERT(type >= FIRST_TYPE && type < NUMBER_OF_TYPES); 3343 int type_int = static_cast<int>(type); 3344 return static_cast<Type>(++type_int); 3345 } 3346 3347 DISALLOW_IMPLICIT_CONSTRUCTORS(ConstantPoolArray); 3348 }; 3349 3350 3351 // DescriptorArrays are fixed arrays used to hold instance descriptors. 3352 // The format of the these objects is: 3353 // [0]: Number of descriptors 3354 // [1]: Either Smi(0) if uninitialized, or a pointer to small fixed array: 3355 // [0]: pointer to fixed array with enum cache 3356 // [1]: either Smi(0) or pointer to fixed array with indices 3357 // [2]: first key 3358 // [2 + number of descriptors * kDescriptorSize]: start of slack 3359 class DescriptorArray: public FixedArray { 3360 public: 3361 // Returns true for both shared empty_descriptor_array and for smis, which the 3362 // map uses to encode additional bit fields when the descriptor array is not 3363 // yet used. 3364 inline bool IsEmpty(); 3365 3366 // Returns the number of descriptors in the array. 3367 int number_of_descriptors() { 3368 ASSERT(length() >= kFirstIndex || IsEmpty()); 3369 int len = length(); 3370 return len == 0 ? 0 : Smi::cast(get(kDescriptorLengthIndex))->value(); 3371 } 3372 3373 int number_of_descriptors_storage() { 3374 int len = length(); 3375 return len == 0 ? 0 : (len - kFirstIndex) / kDescriptorSize; 3376 } 3377 3378 int NumberOfSlackDescriptors() { 3379 return number_of_descriptors_storage() - number_of_descriptors(); 3380 } 3381 3382 inline void SetNumberOfDescriptors(int number_of_descriptors); 3383 inline int number_of_entries() { return number_of_descriptors(); } 3384 3385 bool HasEnumCache() { 3386 return !IsEmpty() && !get(kEnumCacheIndex)->IsSmi(); 3387 } 3388 3389 void CopyEnumCacheFrom(DescriptorArray* array) { 3390 set(kEnumCacheIndex, array->get(kEnumCacheIndex)); 3391 } 3392 3393 FixedArray* GetEnumCache() { 3394 ASSERT(HasEnumCache()); 3395 FixedArray* bridge = FixedArray::cast(get(kEnumCacheIndex)); 3396 return FixedArray::cast(bridge->get(kEnumCacheBridgeCacheIndex)); 3397 } 3398 3399 bool HasEnumIndicesCache() { 3400 if (IsEmpty()) return false; 3401 Object* object = get(kEnumCacheIndex); 3402 if (object->IsSmi()) return false; 3403 FixedArray* bridge = FixedArray::cast(object); 3404 return !bridge->get(kEnumCacheBridgeIndicesCacheIndex)->IsSmi(); 3405 } 3406 3407 FixedArray* GetEnumIndicesCache() { 3408 ASSERT(HasEnumIndicesCache()); 3409 FixedArray* bridge = FixedArray::cast(get(kEnumCacheIndex)); 3410 return FixedArray::cast(bridge->get(kEnumCacheBridgeIndicesCacheIndex)); 3411 } 3412 3413 Object** GetEnumCacheSlot() { 3414 ASSERT(HasEnumCache()); 3415 return HeapObject::RawField(reinterpret_cast<HeapObject*>(this), 3416 kEnumCacheOffset); 3417 } 3418 3419 void ClearEnumCache(); 3420 3421 // Initialize or change the enum cache, 3422 // using the supplied storage for the small "bridge". 3423 void SetEnumCache(FixedArray* bridge_storage, 3424 FixedArray* new_cache, 3425 Object* new_index_cache); 3426 3427 // Accessors for fetching instance descriptor at descriptor number. 3428 inline Name* GetKey(int descriptor_number); 3429 inline Object** GetKeySlot(int descriptor_number); 3430 inline Object* GetValue(int descriptor_number); 3431 inline void SetValue(int descriptor_number, Object* value); 3432 inline Object** GetValueSlot(int descriptor_number); 3433 inline Object** GetDescriptorStartSlot(int descriptor_number); 3434 inline Object** GetDescriptorEndSlot(int descriptor_number); 3435 inline PropertyDetails GetDetails(int descriptor_number); 3436 inline PropertyType GetType(int descriptor_number); 3437 inline int GetFieldIndex(int descriptor_number); 3438 inline HeapType* GetFieldType(int descriptor_number); 3439 inline Object* GetConstant(int descriptor_number); 3440 inline Object* GetCallbacksObject(int descriptor_number); 3441 inline AccessorDescriptor* GetCallbacks(int descriptor_number); 3442 3443 inline Name* GetSortedKey(int descriptor_number); 3444 inline int GetSortedKeyIndex(int descriptor_number); 3445 inline void SetSortedKey(int pointer, int descriptor_number); 3446 inline void SetRepresentation(int descriptor_number, 3447 Representation representation); 3448 3449 // Accessor for complete descriptor. 3450 inline void Get(int descriptor_number, Descriptor* desc); 3451 inline void Set(int descriptor_number, Descriptor* desc); 3452 void Replace(int descriptor_number, Descriptor* descriptor); 3453 3454 // Append automatically sets the enumeration index. This should only be used 3455 // to add descriptors in bulk at the end, followed by sorting the descriptor 3456 // array. 3457 inline void Append(Descriptor* desc); 3458 3459 static Handle<DescriptorArray> CopyUpTo(Handle<DescriptorArray> desc, 3460 int enumeration_index, 3461 int slack = 0); 3462 3463 static Handle<DescriptorArray> CopyUpToAddAttributes( 3464 Handle<DescriptorArray> desc, 3465 int enumeration_index, 3466 PropertyAttributes attributes, 3467 int slack = 0); 3468 3469 // Sort the instance descriptors by the hash codes of their keys. 3470 void Sort(); 3471 3472 // Search the instance descriptors for given name. 3473 INLINE(int Search(Name* name, int number_of_own_descriptors)); 3474 3475 // As the above, but uses DescriptorLookupCache and updates it when 3476 // necessary. 3477 INLINE(int SearchWithCache(Name* name, Map* map)); 3478 3479 // Allocates a DescriptorArray, but returns the singleton 3480 // empty descriptor array object if number_of_descriptors is 0. 3481 static Handle<DescriptorArray> Allocate(Isolate* isolate, 3482 int number_of_descriptors, 3483 int slack = 0); 3484 3485 // Casting. 3486 static inline DescriptorArray* cast(Object* obj); 3487 3488 // Constant for denoting key was not found. 3489 static const int kNotFound = -1; 3490 3491 static const int kDescriptorLengthIndex = 0; 3492 static const int kEnumCacheIndex = 1; 3493 static const int kFirstIndex = 2; 3494 3495 // The length of the "bridge" to the enum cache. 3496 static const int kEnumCacheBridgeLength = 2; 3497 static const int kEnumCacheBridgeCacheIndex = 0; 3498 static const int kEnumCacheBridgeIndicesCacheIndex = 1; 3499 3500 // Layout description. 3501 static const int kDescriptorLengthOffset = FixedArray::kHeaderSize; 3502 static const int kEnumCacheOffset = kDescriptorLengthOffset + kPointerSize; 3503 static const int kFirstOffset = kEnumCacheOffset + kPointerSize; 3504 3505 // Layout description for the bridge array. 3506 static const int kEnumCacheBridgeCacheOffset = FixedArray::kHeaderSize; 3507 3508 // Layout of descriptor. 3509 static const int kDescriptorKey = 0; 3510 static const int kDescriptorDetails = 1; 3511 static const int kDescriptorValue = 2; 3512 static const int kDescriptorSize = 3; 3513 3514 #ifdef OBJECT_PRINT 3515 // Print all the descriptors. 3516 void PrintDescriptors(FILE* out = stdout); 3517 #endif 3518 3519 #ifdef DEBUG 3520 // Is the descriptor array sorted and without duplicates? 3521 bool IsSortedNoDuplicates(int valid_descriptors = -1); 3522 3523 // Is the descriptor array consistent with the back pointers in targets? 3524 bool IsConsistentWithBackPointers(Map* current_map); 3525 3526 // Are two DescriptorArrays equal? 3527 bool IsEqualTo(DescriptorArray* other); 3528 #endif 3529 3530 // Returns the fixed array length required to hold number_of_descriptors 3531 // descriptors. 3532 static int LengthFor(int number_of_descriptors) { 3533 return ToKeyIndex(number_of_descriptors); 3534 } 3535 3536 private: 3537 // WhitenessWitness is used to prove that a descriptor array is white 3538 // (unmarked), so incremental write barriers can be skipped because the 3539 // marking invariant cannot be broken and slots pointing into evacuation 3540 // candidates will be discovered when the object is scanned. A witness is 3541 // always stack-allocated right after creating an array. By allocating a 3542 // witness, incremental marking is globally disabled. The witness is then 3543 // passed along wherever needed to statically prove that the array is known to 3544 // be white. 3545 class WhitenessWitness { 3546 public: 3547 inline explicit WhitenessWitness(DescriptorArray* array); 3548 inline ~WhitenessWitness(); 3549 3550 private: 3551 IncrementalMarking* marking_; 3552 }; 3553 3554 // An entry in a DescriptorArray, represented as an (array, index) pair. 3555 class Entry { 3556 public: 3557 inline explicit Entry(DescriptorArray* descs, int index) : 3558 descs_(descs), index_(index) { } 3559 3560 inline PropertyType type() { return descs_->GetType(index_); } 3561 inline Object* GetCallbackObject() { return descs_->GetValue(index_); } 3562 3563 private: 3564 DescriptorArray* descs_; 3565 int index_; 3566 }; 3567 3568 // Conversion from descriptor number to array indices. 3569 static int ToKeyIndex(int descriptor_number) { 3570 return kFirstIndex + 3571 (descriptor_number * kDescriptorSize) + 3572 kDescriptorKey; 3573 } 3574 3575 static int ToDetailsIndex(int descriptor_number) { 3576 return kFirstIndex + 3577 (descriptor_number * kDescriptorSize) + 3578 kDescriptorDetails; 3579 } 3580 3581 static int ToValueIndex(int descriptor_number) { 3582 return kFirstIndex + 3583 (descriptor_number * kDescriptorSize) + 3584 kDescriptorValue; 3585 } 3586 3587 // Transfer a complete descriptor from the src descriptor array to this 3588 // descriptor array. 3589 void CopyFrom(int index, 3590 DescriptorArray* src, 3591 const WhitenessWitness&); 3592 3593 inline void Set(int descriptor_number, 3594 Descriptor* desc, 3595 const WhitenessWitness&); 3596 3597 inline void Append(Descriptor* desc, const WhitenessWitness&); 3598 3599 // Swap first and second descriptor. 3600 inline void SwapSortedKeys(int first, int second); 3601 3602 DISALLOW_IMPLICIT_CONSTRUCTORS(DescriptorArray); 3603 }; 3604 3605 3606 enum SearchMode { ALL_ENTRIES, VALID_ENTRIES }; 3607 3608 template<SearchMode search_mode, typename T> 3609 inline int LinearSearch(T* array, Name* name, int len, int valid_entries); 3610 3611 3612 template<SearchMode search_mode, typename T> 3613 inline int Search(T* array, Name* name, int valid_entries = 0); 3614 3615 3616 // HashTable is a subclass of FixedArray that implements a hash table 3617 // that uses open addressing and quadratic probing. 3618 // 3619 // In order for the quadratic probing to work, elements that have not 3620 // yet been used and elements that have been deleted are 3621 // distinguished. Probing continues when deleted elements are 3622 // encountered and stops when unused elements are encountered. 3623 // 3624 // - Elements with key == undefined have not been used yet. 3625 // - Elements with key == the_hole have been deleted. 3626 // 3627 // The hash table class is parameterized with a Shape and a Key. 3628 // Shape must be a class with the following interface: 3629 // class ExampleShape { 3630 // public: 3631 // // Tells whether key matches other. 3632 // static bool IsMatch(Key key, Object* other); 3633 // // Returns the hash value for key. 3634 // static uint32_t Hash(Key key); 3635 // // Returns the hash value for object. 3636 // static uint32_t HashForObject(Key key, Object* object); 3637 // // Convert key to an object. 3638 // static inline Handle<Object> AsHandle(Isolate* isolate, Key key); 3639 // // The prefix size indicates number of elements in the beginning 3640 // // of the backing storage. 3641 // static const int kPrefixSize = ..; 3642 // // The Element size indicates number of elements per entry. 3643 // static const int kEntrySize = ..; 3644 // }; 3645 // The prefix size indicates an amount of memory in the 3646 // beginning of the backing storage that can be used for non-element 3647 // information by subclasses. 3648 3649 template<typename Key> 3650 class BaseShape { 3651 public: 3652 static const bool UsesSeed = false; 3653 static uint32_t Hash(Key key) { return 0; } 3654 static uint32_t SeededHash(Key key, uint32_t seed) { 3655 ASSERT(UsesSeed); 3656 return Hash(key); 3657 } 3658 static uint32_t HashForObject(Key key, Object* object) { return 0; } 3659 static uint32_t SeededHashForObject(Key key, uint32_t seed, Object* object) { 3660 ASSERT(UsesSeed); 3661 return HashForObject(key, object); 3662 } 3663 }; 3664 3665 template<typename Derived, typename Shape, typename Key> 3666 class HashTable: public FixedArray { 3667 public: 3668 // Wrapper methods 3669 inline uint32_t Hash(Key key) { 3670 if (Shape::UsesSeed) { 3671 return Shape::SeededHash(key, GetHeap()->HashSeed()); 3672 } else { 3673 return Shape::Hash(key); 3674 } 3675 } 3676 3677 inline uint32_t HashForObject(Key key, Object* object) { 3678 if (Shape::UsesSeed) { 3679 return Shape::SeededHashForObject(key, GetHeap()->HashSeed(), object); 3680 } else { 3681 return Shape::HashForObject(key, object); 3682 } 3683 } 3684 3685 // Returns the number of elements in the hash table. 3686 int NumberOfElements() { 3687 return Smi::cast(get(kNumberOfElementsIndex))->value(); 3688 } 3689 3690 // Returns the number of deleted elements in the hash table. 3691 int NumberOfDeletedElements() { 3692 return Smi::cast(get(kNumberOfDeletedElementsIndex))->value(); 3693 } 3694 3695 // Returns the capacity of the hash table. 3696 int Capacity() { 3697 return Smi::cast(get(kCapacityIndex))->value(); 3698 } 3699 3700 // ElementAdded should be called whenever an element is added to a 3701 // hash table. 3702 void ElementAdded() { SetNumberOfElements(NumberOfElements() + 1); } 3703 3704 // ElementRemoved should be called whenever an element is removed from 3705 // a hash table. 3706 void ElementRemoved() { 3707 SetNumberOfElements(NumberOfElements() - 1); 3708 SetNumberOfDeletedElements(NumberOfDeletedElements() + 1); 3709 } 3710 void ElementsRemoved(int n) { 3711 SetNumberOfElements(NumberOfElements() - n); 3712 SetNumberOfDeletedElements(NumberOfDeletedElements() + n); 3713 } 3714 3715 // Returns a new HashTable object. 3716 MUST_USE_RESULT static Handle<Derived> New( 3717 Isolate* isolate, 3718 int at_least_space_for, 3719 MinimumCapacity capacity_option = USE_DEFAULT_MINIMUM_CAPACITY, 3720 PretenureFlag pretenure = NOT_TENURED); 3721 3722 // Computes the required capacity for a table holding the given 3723 // number of elements. May be more than HashTable::kMaxCapacity. 3724 static int ComputeCapacity(int at_least_space_for); 3725 3726 // Returns the key at entry. 3727 Object* KeyAt(int entry) { return get(EntryToIndex(entry)); } 3728 3729 // Tells whether k is a real key. The hole and undefined are not allowed 3730 // as keys and can be used to indicate missing or deleted elements. 3731 bool IsKey(Object* k) { 3732 return !k->IsTheHole() && !k->IsUndefined(); 3733 } 3734 3735 // Garbage collection support. 3736 void IteratePrefix(ObjectVisitor* visitor); 3737 void IterateElements(ObjectVisitor* visitor); 3738 3739 // Casting. 3740 static inline HashTable* cast(Object* obj); 3741 3742 // Compute the probe offset (quadratic probing). 3743 INLINE(static uint32_t GetProbeOffset(uint32_t n)) { 3744 return (n + n * n) >> 1; 3745 } 3746 3747 static const int kNumberOfElementsIndex = 0; 3748 static const int kNumberOfDeletedElementsIndex = 1; 3749 static const int kCapacityIndex = 2; 3750 static const int kPrefixStartIndex = 3; 3751 static const int kElementsStartIndex = 3752 kPrefixStartIndex + Shape::kPrefixSize; 3753 static const int kEntrySize = Shape::kEntrySize; 3754 static const int kElementsStartOffset = 3755 kHeaderSize + kElementsStartIndex * kPointerSize; 3756 static const int kCapacityOffset = 3757 kHeaderSize + kCapacityIndex * kPointerSize; 3758 3759 // Constant used for denoting a absent entry. 3760 static const int kNotFound = -1; 3761 3762 // Maximal capacity of HashTable. Based on maximal length of underlying 3763 // FixedArray. Staying below kMaxCapacity also ensures that EntryToIndex 3764 // cannot overflow. 3765 static const int kMaxCapacity = 3766 (FixedArray::kMaxLength - kElementsStartOffset) / kEntrySize; 3767 3768 // Find entry for key otherwise return kNotFound. 3769 inline int FindEntry(Key key); 3770 int FindEntry(Isolate* isolate, Key key); 3771 3772 // Rehashes the table in-place. 3773 void Rehash(Key key); 3774 3775 protected: 3776 friend class ObjectHashTable; 3777 3778 // Find the entry at which to insert element with the given key that 3779 // has the given hash value. 3780 uint32_t FindInsertionEntry(uint32_t hash); 3781 3782 // Returns the index for an entry (of the key) 3783 static inline int EntryToIndex(int entry) { 3784 return (entry * kEntrySize) + kElementsStartIndex; 3785 } 3786 3787 // Update the number of elements in the hash table. 3788 void SetNumberOfElements(int nof) { 3789 set(kNumberOfElementsIndex, Smi::FromInt(nof)); 3790 } 3791 3792 // Update the number of deleted elements in the hash table. 3793 void SetNumberOfDeletedElements(int nod) { 3794 set(kNumberOfDeletedElementsIndex, Smi::FromInt(nod)); 3795 } 3796 3797 // Sets the capacity of the hash table. 3798 void SetCapacity(int capacity) { 3799 // To scale a computed hash code to fit within the hash table, we 3800 // use bit-wise AND with a mask, so the capacity must be positive 3801 // and non-zero. 3802 ASSERT(capacity > 0); 3803 ASSERT(capacity <= kMaxCapacity); 3804 set(kCapacityIndex, Smi::FromInt(capacity)); 3805 } 3806 3807 3808 // Returns probe entry. 3809 static uint32_t GetProbe(uint32_t hash, uint32_t number, uint32_t size) { 3810 ASSERT(IsPowerOf2(size)); 3811 return (hash + GetProbeOffset(number)) & (size - 1); 3812 } 3813 3814 inline static uint32_t FirstProbe(uint32_t hash, uint32_t size) { 3815 return hash & (size - 1); 3816 } 3817 3818 inline static uint32_t NextProbe( 3819 uint32_t last, uint32_t number, uint32_t size) { 3820 return (last + number) & (size - 1); 3821 } 3822 3823 // Attempt to shrink hash table after removal of key. 3824 MUST_USE_RESULT static Handle<Derived> Shrink(Handle<Derived> table, Key key); 3825 3826 // Ensure enough space for n additional elements. 3827 MUST_USE_RESULT static Handle<Derived> EnsureCapacity( 3828 Handle<Derived> table, 3829 int n, 3830 Key key, 3831 PretenureFlag pretenure = NOT_TENURED); 3832 3833 private: 3834 // Returns _expected_ if one of entries given by the first _probe_ probes is 3835 // equal to _expected_. Otherwise, returns the entry given by the probe 3836 // number _probe_. 3837 uint32_t EntryForProbe(Key key, Object* k, int probe, uint32_t expected); 3838 3839 void Swap(uint32_t entry1, uint32_t entry2, WriteBarrierMode mode); 3840 3841 // Rehashes this hash-table into the new table. 3842 void Rehash(Handle<Derived> new_table, Key key); 3843 }; 3844 3845 3846 // HashTableKey is an abstract superclass for virtual key behavior. 3847 class HashTableKey { 3848 public: 3849 // Returns whether the other object matches this key. 3850 virtual bool IsMatch(Object* other) = 0; 3851 // Returns the hash value for this key. 3852 virtual uint32_t Hash() = 0; 3853 // Returns the hash value for object. 3854 virtual uint32_t HashForObject(Object* key) = 0; 3855 // Returns the key object for storing into the hash table. 3856 MUST_USE_RESULT virtual Handle<Object> AsHandle(Isolate* isolate) = 0; 3857 // Required. 3858 virtual ~HashTableKey() {} 3859 }; 3860 3861 3862 class StringTableShape : public BaseShape<HashTableKey*> { 3863 public: 3864 static inline bool IsMatch(HashTableKey* key, Object* value) { 3865 return key->IsMatch(value); 3866 } 3867 3868 static inline uint32_t Hash(HashTableKey* key) { 3869 return key->Hash(); 3870 } 3871 3872 static inline uint32_t HashForObject(HashTableKey* key, Object* object) { 3873 return key->HashForObject(object); 3874 } 3875 3876 static inline Handle<Object> AsHandle(Isolate* isolate, HashTableKey* key); 3877 3878 static const int kPrefixSize = 0; 3879 static const int kEntrySize = 1; 3880 }; 3881 3882 class SeqOneByteString; 3883 3884 // StringTable. 3885 // 3886 // No special elements in the prefix and the element size is 1 3887 // because only the string itself (the key) needs to be stored. 3888 class StringTable: public HashTable<StringTable, 3889 StringTableShape, 3890 HashTableKey*> { 3891 public: 3892 // Find string in the string table. If it is not there yet, it is 3893 // added. The return value is the string found. 3894 static Handle<String> LookupString(Isolate* isolate, Handle<String> key); 3895 static Handle<String> LookupKey(Isolate* isolate, HashTableKey* key); 3896 3897 // Tries to internalize given string and returns string handle on success 3898 // or an empty handle otherwise. 3899 MUST_USE_RESULT static MaybeHandle<String> InternalizeStringIfExists( 3900 Isolate* isolate, 3901 Handle<String> string); 3902 3903 // Looks up a string that is equal to the given string and returns 3904 // string handle if it is found, or an empty handle otherwise. 3905 MUST_USE_RESULT static MaybeHandle<String> LookupStringIfExists( 3906 Isolate* isolate, 3907 Handle<String> str); 3908 MUST_USE_RESULT static MaybeHandle<String> LookupTwoCharsStringIfExists( 3909 Isolate* isolate, 3910 uint16_t c1, 3911 uint16_t c2); 3912 3913 // Casting. 3914 static inline StringTable* cast(Object* obj); 3915 3916 private: 3917 template <bool seq_ascii> friend class JsonParser; 3918 3919 DISALLOW_IMPLICIT_CONSTRUCTORS(StringTable); 3920 }; 3921 3922 3923 class MapCacheShape : public BaseShape<HashTableKey*> { 3924 public: 3925 static inline bool IsMatch(HashTableKey* key, Object* value) { 3926 return key->IsMatch(value); 3927 } 3928 3929 static inline uint32_t Hash(HashTableKey* key) { 3930 return key->Hash(); 3931 } 3932 3933 static inline uint32_t HashForObject(HashTableKey* key, Object* object) { 3934 return key->HashForObject(object); 3935 } 3936 3937 static inline Handle<Object> AsHandle(Isolate* isolate, HashTableKey* key); 3938 3939 static const int kPrefixSize = 0; 3940 static const int kEntrySize = 2; 3941 }; 3942 3943 3944 // MapCache. 3945 // 3946 // Maps keys that are a fixed array of unique names to a map. 3947 // Used for canonicalize maps for object literals. 3948 class MapCache: public HashTable<MapCache, MapCacheShape, HashTableKey*> { 3949 public: 3950 // Find cached value for a name key, otherwise return null. 3951 Object* Lookup(FixedArray* key); 3952 static Handle<MapCache> Put( 3953 Handle<MapCache> map_cache, Handle<FixedArray> key, Handle<Map> value); 3954 static inline MapCache* cast(Object* obj); 3955 3956 private: 3957 DISALLOW_IMPLICIT_CONSTRUCTORS(MapCache); 3958 }; 3959 3960 3961 template <typename Derived, typename Shape, typename Key> 3962 class Dictionary: public HashTable<Derived, Shape, Key> { 3963 protected: 3964 typedef HashTable<Derived, Shape, Key> DerivedHashTable; 3965 3966 public: 3967 static inline Dictionary* cast(Object* obj) { 3968 return reinterpret_cast<Dictionary*>(obj); 3969 } 3970 3971 // Returns the value at entry. 3972 Object* ValueAt(int entry) { 3973 return this->get(DerivedHashTable::EntryToIndex(entry) + 1); 3974 } 3975 3976 // Set the value for entry. 3977 void ValueAtPut(int entry, Object* value) { 3978 this->set(DerivedHashTable::EntryToIndex(entry) + 1, value); 3979 } 3980 3981 // Returns the property details for the property at entry. 3982 PropertyDetails DetailsAt(int entry) { 3983 ASSERT(entry >= 0); // Not found is -1, which is not caught by get(). 3984 return PropertyDetails( 3985 Smi::cast(this->get(DerivedHashTable::EntryToIndex(entry) + 2))); 3986 } 3987 3988 // Set the details for entry. 3989 void DetailsAtPut(int entry, PropertyDetails value) { 3990 this->set(DerivedHashTable::EntryToIndex(entry) + 2, value.AsSmi()); 3991 } 3992 3993 // Sorting support 3994 void CopyValuesTo(FixedArray* elements); 3995 3996 // Delete a property from the dictionary. 3997 static Handle<Object> DeleteProperty( 3998 Handle<Derived> dictionary, 3999 int entry, 4000 JSObject::DeleteMode mode); 4001 4002 // Attempt to shrink the dictionary after deletion of key. 4003 MUST_USE_RESULT static inline Handle<Derived> Shrink( 4004 Handle<Derived> dictionary, 4005 Key key) { 4006 return DerivedHashTable::Shrink(dictionary, key); 4007 } 4008 4009 // Returns the number of elements in the dictionary filtering out properties 4010 // with the specified attributes. 4011 int NumberOfElementsFilterAttributes(PropertyAttributes filter); 4012 4013 // Returns the number of enumerable elements in the dictionary. 4014 int NumberOfEnumElements(); 4015 4016 enum SortMode { UNSORTED, SORTED }; 4017 // Copies keys to preallocated fixed array. 4018 void CopyKeysTo(FixedArray* storage, 4019 PropertyAttributes filter, 4020 SortMode sort_mode); 4021 // Fill in details for properties into storage. 4022 void CopyKeysTo(FixedArray* storage, 4023 int index, 4024 PropertyAttributes filter, 4025 SortMode sort_mode); 4026 4027 // Accessors for next enumeration index. 4028 void SetNextEnumerationIndex(int index) { 4029 ASSERT(index != 0); 4030 this->set(kNextEnumerationIndexIndex, Smi::FromInt(index)); 4031 } 4032 4033 int NextEnumerationIndex() { 4034 return Smi::cast(this->get(kNextEnumerationIndexIndex))->value(); 4035 } 4036 4037 // Creates a new dictionary. 4038 MUST_USE_RESULT static Handle<Derived> New( 4039 Isolate* isolate, 4040 int at_least_space_for, 4041 PretenureFlag pretenure = NOT_TENURED); 4042 4043 // Ensure enough space for n additional elements. 4044 static Handle<Derived> EnsureCapacity(Handle<Derived> obj, int n, Key key); 4045 4046 #ifdef OBJECT_PRINT 4047 void Print(FILE* out = stdout); 4048 #endif 4049 // Returns the key (slow). 4050 Object* SlowReverseLookup(Object* value); 4051 4052 // Sets the entry to (key, value) pair. 4053 inline void SetEntry(int entry, 4054 Handle<Object> key, 4055 Handle<Object> value); 4056 inline void SetEntry(int entry, 4057 Handle<Object> key, 4058 Handle<Object> value, 4059 PropertyDetails details); 4060 4061 MUST_USE_RESULT static Handle<Derived> Add( 4062 Handle<Derived> dictionary, 4063 Key key, 4064 Handle<Object> value, 4065 PropertyDetails details); 4066 4067 protected: 4068 // Generic at put operation. 4069 MUST_USE_RESULT static Handle<Derived> AtPut( 4070 Handle<Derived> dictionary, 4071 Key key, 4072 Handle<Object> value); 4073 4074 // Add entry to dictionary. 4075 static void AddEntry( 4076 Handle<Derived> dictionary, 4077 Key key, 4078 Handle<Object> value, 4079 PropertyDetails details, 4080 uint32_t hash); 4081 4082 // Generate new enumeration indices to avoid enumeration index overflow. 4083 static void GenerateNewEnumerationIndices(Handle<Derived> dictionary); 4084 static const int kMaxNumberKeyIndex = DerivedHashTable::kPrefixStartIndex; 4085 static const int kNextEnumerationIndexIndex = kMaxNumberKeyIndex + 1; 4086 }; 4087 4088 4089 class NameDictionaryShape : public BaseShape<Handle<Name> > { 4090 public: 4091 static inline bool IsMatch(Handle<Name> key, Object* other); 4092 static inline uint32_t Hash(Handle<Name> key); 4093 static inline uint32_t HashForObject(Handle<Name> key, Object* object); 4094 static inline Handle<Object> AsHandle(Isolate* isolate, Handle<Name> key); 4095 static const int kPrefixSize = 2; 4096 static const int kEntrySize = 3; 4097 static const bool kIsEnumerable = true; 4098 }; 4099 4100 4101 class NameDictionary: public Dictionary<NameDictionary, 4102 NameDictionaryShape, 4103 Handle<Name> > { 4104 typedef Dictionary< 4105 NameDictionary, NameDictionaryShape, Handle<Name> > DerivedDictionary; 4106 4107 public: 4108 static inline NameDictionary* cast(Object* obj) { 4109 ASSERT(obj->IsDictionary()); 4110 return reinterpret_cast<NameDictionary*>(obj); 4111 } 4112 4113 // Copies enumerable keys to preallocated fixed array. 4114 void CopyEnumKeysTo(FixedArray* storage); 4115 inline static void DoGenerateNewEnumerationIndices( 4116 Handle<NameDictionary> dictionary); 4117 4118 // Find entry for key, otherwise return kNotFound. Optimized version of 4119 // HashTable::FindEntry. 4120 int FindEntry(Handle<Name> key); 4121 }; 4122 4123 4124 class NumberDictionaryShape : public BaseShape<uint32_t> { 4125 public: 4126 static inline bool IsMatch(uint32_t key, Object* other); 4127 static inline Handle<Object> AsHandle(Isolate* isolate, uint32_t key); 4128 static const int kEntrySize = 3; 4129 static const bool kIsEnumerable = false; 4130 }; 4131 4132 4133 class SeededNumberDictionaryShape : public NumberDictionaryShape { 4134 public: 4135 static const bool UsesSeed = true; 4136 static const int kPrefixSize = 2; 4137 4138 static inline uint32_t SeededHash(uint32_t key, uint32_t seed); 4139 static inline uint32_t SeededHashForObject(uint32_t key, 4140 uint32_t seed, 4141 Object* object); 4142 }; 4143 4144 4145 class UnseededNumberDictionaryShape : public NumberDictionaryShape { 4146 public: 4147 static const int kPrefixSize = 0; 4148 4149 static inline uint32_t Hash(uint32_t key); 4150 static inline uint32_t HashForObject(uint32_t key, Object* object); 4151 }; 4152 4153 4154 class SeededNumberDictionary 4155 : public Dictionary<SeededNumberDictionary, 4156 SeededNumberDictionaryShape, 4157 uint32_t> { 4158 public: 4159 static SeededNumberDictionary* cast(Object* obj) { 4160 ASSERT(obj->IsDictionary()); 4161 return reinterpret_cast<SeededNumberDictionary*>(obj); 4162 } 4163 4164 // Type specific at put (default NONE attributes is used when adding). 4165 MUST_USE_RESULT static Handle<SeededNumberDictionary> AtNumberPut( 4166 Handle<SeededNumberDictionary> dictionary, 4167 uint32_t key, 4168 Handle<Object> value); 4169 MUST_USE_RESULT static Handle<SeededNumberDictionary> AddNumberEntry( 4170 Handle<SeededNumberDictionary> dictionary, 4171 uint32_t key, 4172 Handle<Object> value, 4173 PropertyDetails details); 4174 4175 // Set an existing entry or add a new one if needed. 4176 // Return the updated dictionary. 4177 MUST_USE_RESULT static Handle<SeededNumberDictionary> Set( 4178 Handle<SeededNumberDictionary> dictionary, 4179 uint32_t key, 4180 Handle<Object> value, 4181 PropertyDetails details); 4182 4183 void UpdateMaxNumberKey(uint32_t key); 4184 4185 // If slow elements are required we will never go back to fast-case 4186 // for the elements kept in this dictionary. We require slow 4187 // elements if an element has been added at an index larger than 4188 // kRequiresSlowElementsLimit or set_requires_slow_elements() has been called 4189 // when defining a getter or setter with a number key. 4190 inline bool requires_slow_elements(); 4191 inline void set_requires_slow_elements(); 4192 4193 // Get the value of the max number key that has been added to this 4194 // dictionary. max_number_key can only be called if 4195 // requires_slow_elements returns false. 4196 inline uint32_t max_number_key(); 4197 4198 // Bit masks. 4199 static const int kRequiresSlowElementsMask = 1; 4200 static const int kRequiresSlowElementsTagSize = 1; 4201 static const uint32_t kRequiresSlowElementsLimit = (1 << 29) - 1; 4202 }; 4203 4204 4205 class UnseededNumberDictionary 4206 : public Dictionary<UnseededNumberDictionary, 4207 UnseededNumberDictionaryShape, 4208 uint32_t> { 4209 public: 4210 static UnseededNumberDictionary* cast(Object* obj) { 4211 ASSERT(obj->IsDictionary()); 4212 return reinterpret_cast<UnseededNumberDictionary*>(obj); 4213 } 4214 4215 // Type specific at put (default NONE attributes is used when adding). 4216 MUST_USE_RESULT static Handle<UnseededNumberDictionary> AtNumberPut( 4217 Handle<UnseededNumberDictionary> dictionary, 4218 uint32_t key, 4219 Handle<Object> value); 4220 MUST_USE_RESULT static Handle<UnseededNumberDictionary> AddNumberEntry( 4221 Handle<UnseededNumberDictionary> dictionary, 4222 uint32_t key, 4223 Handle<Object> value); 4224 4225 // Set an existing entry or add a new one if needed. 4226 // Return the updated dictionary. 4227 MUST_USE_RESULT static Handle<UnseededNumberDictionary> Set( 4228 Handle<UnseededNumberDictionary> dictionary, 4229 uint32_t key, 4230 Handle<Object> value); 4231 }; 4232 4233 4234 class ObjectHashTableShape : public BaseShape<Handle<Object> > { 4235 public: 4236 static inline bool IsMatch(Handle<Object> key, Object* other); 4237 static inline uint32_t Hash(Handle<Object> key); 4238 static inline uint32_t HashForObject(Handle<Object> key, Object* object); 4239 static inline Handle<Object> AsHandle(Isolate* isolate, Handle<Object> key); 4240 static const int kPrefixSize = 0; 4241 static const int kEntrySize = 2; 4242 }; 4243 4244 4245 // ObjectHashTable maps keys that are arbitrary objects to object values by 4246 // using the identity hash of the key for hashing purposes. 4247 class ObjectHashTable: public HashTable<ObjectHashTable, 4248 ObjectHashTableShape, 4249 Handle<Object> > { 4250 typedef HashTable< 4251 ObjectHashTable, ObjectHashTableShape, Handle<Object> > DerivedHashTable; 4252 public: 4253 static inline ObjectHashTable* cast(Object* obj) { 4254 ASSERT(obj->IsHashTable()); 4255 return reinterpret_cast<ObjectHashTable*>(obj); 4256 } 4257 4258 // Attempt to shrink hash table after removal of key. 4259 MUST_USE_RESULT static inline Handle<ObjectHashTable> Shrink( 4260 Handle<ObjectHashTable> table, 4261 Handle<Object> key); 4262 4263 // Looks up the value associated with the given key. The hole value is 4264 // returned in case the key is not present. 4265 Object* Lookup(Handle<Object> key); 4266 4267 // Adds (or overwrites) the value associated with the given key. 4268 static Handle<ObjectHashTable> Put(Handle<ObjectHashTable> table, 4269 Handle<Object> key, 4270 Handle<Object> value); 4271 4272 // Returns an ObjectHashTable (possibly |table|) where |key| has been removed. 4273 static Handle<ObjectHashTable> Remove(Handle<ObjectHashTable> table, 4274 Handle<Object> key, 4275 bool* was_present); 4276 4277 private: 4278 friend class MarkCompactCollector; 4279 4280 void AddEntry(int entry, Object* key, Object* value); 4281 void RemoveEntry(int entry); 4282 4283 // Returns the index to the value of an entry. 4284 static inline int EntryToValueIndex(int entry) { 4285 return EntryToIndex(entry) + 1; 4286 } 4287 }; 4288 4289 4290 // OrderedHashTable is a HashTable with Object keys that preserves 4291 // insertion order. There are Map and Set interfaces (OrderedHashMap 4292 // and OrderedHashTable, below). It is meant to be used by JSMap/JSSet. 4293 // 4294 // Only Object* keys are supported, with Object::SameValueZero() used as the 4295 // equality operator and Object::GetHash() for the hash function. 4296 // 4297 // Based on the "Deterministic Hash Table" as described by Jason Orendorff at 4298 // https://wiki.mozilla.org/User:Jorend/Deterministic_hash_tables 4299 // Originally attributed to Tyler Close. 4300 // 4301 // Memory layout: 4302 // [0]: bucket count 4303 // [1]: element count 4304 // [2]: deleted element count 4305 // [3..(3 + NumberOfBuckets() - 1)]: "hash table", where each item is an 4306 // offset into the data table (see below) where the 4307 // first item in this bucket is stored. 4308 // [3 + NumberOfBuckets()..length]: "data table", an array of length 4309 // Capacity() * kEntrySize, where the first entrysize 4310 // items are handled by the derived class and the 4311 // item at kChainOffset is another entry into the 4312 // data table indicating the next entry in this hash 4313 // bucket. 4314 // 4315 // When we transition the table to a new version we obsolete it and reuse parts 4316 // of the memory to store information how to transition an iterator to the new 4317 // table: 4318 // 4319 // Memory layout for obsolete table: 4320 // [0]: bucket count 4321 // [1]: Next newer table 4322 // [2]: Number of removed holes or -1 when the table was cleared. 4323 // [3..(3 + NumberOfRemovedHoles() - 1)]: The indexes of the removed holes. 4324 // [3 + NumberOfRemovedHoles()..length]: Not used 4325 // 4326 template<class Derived, class Iterator, int entrysize> 4327 class OrderedHashTable: public FixedArray { 4328 public: 4329 // Returns an OrderedHashTable with a capacity of at least |capacity|. 4330 static Handle<Derived> Allocate( 4331 Isolate* isolate, int capacity, PretenureFlag pretenure = NOT_TENURED); 4332 4333 // Returns an OrderedHashTable (possibly |table|) with enough space 4334 // to add at least one new element. 4335 static Handle<Derived> EnsureGrowable(Handle<Derived> table); 4336 4337 // Returns an OrderedHashTable (possibly |table|) that's shrunken 4338 // if possible. 4339 static Handle<Derived> Shrink(Handle<Derived> table); 4340 4341 // Returns a new empty OrderedHashTable and records the clearing so that 4342 // exisiting iterators can be updated. 4343 static Handle<Derived> Clear(Handle<Derived> table); 4344 4345 // Returns an OrderedHashTable (possibly |table|) where |key| has been 4346 // removed. 4347 static Handle<Derived> Remove(Handle<Derived> table, Handle<Object> key, 4348 bool* was_present); 4349 4350 // Returns kNotFound if the key isn't present. 4351 int FindEntry(Handle<Object> key); 4352 4353 int NumberOfElements() { 4354 return Smi::cast(get(kNumberOfElementsIndex))->value(); 4355 } 4356 4357 int NumberOfDeletedElements() { 4358 return Smi::cast(get(kNumberOfDeletedElementsIndex))->value(); 4359 } 4360 4361 int UsedCapacity() { return NumberOfElements() + NumberOfDeletedElements(); } 4362 4363 int NumberOfBuckets() { 4364 return Smi::cast(get(kNumberOfBucketsIndex))->value(); 4365 } 4366 4367 // Returns the index into the data table where the new entry 4368 // should be placed. The table is assumed to have enough space 4369 // for a new entry. 4370 int AddEntry(int hash); 4371 4372 // Removes the entry, and puts the_hole in entrysize pointers 4373 // (leaving the hash table chain intact). 4374 void RemoveEntry(int entry); 4375 4376 // Returns an index into |this| for the given entry. 4377 int EntryToIndex(int entry) { 4378 return kHashTableStartIndex + NumberOfBuckets() + (entry * kEntrySize); 4379 } 4380 4381 Object* KeyAt(int entry) { return get(EntryToIndex(entry)); } 4382 4383 bool IsObsolete() { 4384 return !get(kNextTableIndex)->IsSmi(); 4385 } 4386 4387 // The next newer table. This is only valid if the table is obsolete. 4388 Derived* NextTable() { 4389 return Derived::cast(get(kNextTableIndex)); 4390 } 4391 4392 // When the table is obsolete we store the indexes of the removed holes. 4393 int RemovedIndexAt(int index) { 4394 return Smi::cast(get(kRemovedHolesIndex + index))->value(); 4395 } 4396 4397 static const int kNotFound = -1; 4398 static const int kMinCapacity = 4; 4399 4400 private: 4401 static Handle<Derived> Rehash(Handle<Derived> table, int new_capacity); 4402 4403 void SetNumberOfBuckets(int num) { 4404 set(kNumberOfBucketsIndex, Smi::FromInt(num)); 4405 } 4406 4407 void SetNumberOfElements(int num) { 4408 set(kNumberOfElementsIndex, Smi::FromInt(num)); 4409 } 4410 4411 void SetNumberOfDeletedElements(int num) { 4412 set(kNumberOfDeletedElementsIndex, Smi::FromInt(num)); 4413 } 4414 4415 int Capacity() { 4416 return NumberOfBuckets() * kLoadFactor; 4417 } 4418 4419 // Returns the next entry for the given entry. 4420 int ChainAt(int entry) { 4421 return Smi::cast(get(EntryToIndex(entry) + kChainOffset))->value(); 4422 } 4423 4424 int HashToBucket(int hash) { 4425 return hash & (NumberOfBuckets() - 1); 4426 } 4427 4428 int HashToEntry(int hash) { 4429 int bucket = HashToBucket(hash); 4430 return Smi::cast(get(kHashTableStartIndex + bucket))->value(); 4431 } 4432 4433 void SetNextTable(Derived* next_table) { 4434 set(kNextTableIndex, next_table); 4435 } 4436 4437 void SetRemovedIndexAt(int index, int removed_index) { 4438 return set(kRemovedHolesIndex + index, Smi::FromInt(removed_index)); 4439 } 4440 4441 static const int kNumberOfBucketsIndex = 0; 4442 static const int kNumberOfElementsIndex = kNumberOfBucketsIndex + 1; 4443 static const int kNumberOfDeletedElementsIndex = kNumberOfElementsIndex + 1; 4444 static const int kHashTableStartIndex = kNumberOfDeletedElementsIndex + 1; 4445 4446 static const int kNextTableIndex = kNumberOfElementsIndex; 4447 static const int kRemovedHolesIndex = kHashTableStartIndex; 4448 4449 static const int kEntrySize = entrysize + 1; 4450 static const int kChainOffset = entrysize; 4451 4452 static const int kLoadFactor = 2; 4453 static const int kMaxCapacity = 4454 (FixedArray::kMaxLength - kHashTableStartIndex) 4455 / (1 + (kEntrySize * kLoadFactor)); 4456 }; 4457 4458 4459 class JSSetIterator; 4460 4461 4462 class OrderedHashSet: public OrderedHashTable< 4463 OrderedHashSet, JSSetIterator, 1> { 4464 public: 4465 static OrderedHashSet* cast(Object* obj) { 4466 ASSERT(obj->IsOrderedHashTable()); 4467 return reinterpret_cast<OrderedHashSet*>(obj); 4468 } 4469 4470 bool Contains(Handle<Object> key); 4471 static Handle<OrderedHashSet> Add( 4472 Handle<OrderedHashSet> table, Handle<Object> key); 4473 }; 4474 4475 4476 class JSMapIterator; 4477 4478 4479 class OrderedHashMap:public OrderedHashTable< 4480 OrderedHashMap, JSMapIterator, 2> { 4481 public: 4482 static OrderedHashMap* cast(Object* obj) { 4483 ASSERT(obj->IsOrderedHashTable()); 4484 return reinterpret_cast<OrderedHashMap*>(obj); 4485 } 4486 4487 Object* Lookup(Handle<Object> key); 4488 static Handle<OrderedHashMap> Put( 4489 Handle<OrderedHashMap> table, 4490 Handle<Object> key, 4491 Handle<Object> value); 4492 4493 private: 4494 Object* ValueAt(int entry) { 4495 return get(EntryToIndex(entry) + kValueOffset); 4496 } 4497 4498 static const int kValueOffset = 1; 4499 }; 4500 4501 4502 template <int entrysize> 4503 class WeakHashTableShape : public BaseShape<Handle<Object> > { 4504 public: 4505 static inline bool IsMatch(Handle<Object> key, Object* other); 4506 static inline uint32_t Hash(Handle<Object> key); 4507 static inline uint32_t HashForObject(Handle<Object> key, Object* object); 4508 static inline Handle<Object> AsHandle(Isolate* isolate, Handle<Object> key); 4509 static const int kPrefixSize = 0; 4510 static const int kEntrySize = entrysize; 4511 }; 4512 4513 4514 // WeakHashTable maps keys that are arbitrary objects to object values. 4515 // It is used for the global weak hash table that maps objects 4516 // embedded in optimized code to dependent code lists. 4517 class WeakHashTable: public HashTable<WeakHashTable, 4518 WeakHashTableShape<2>, 4519 Handle<Object> > { 4520 typedef HashTable< 4521 WeakHashTable, WeakHashTableShape<2>, Handle<Object> > DerivedHashTable; 4522 public: 4523 static inline WeakHashTable* cast(Object* obj) { 4524 ASSERT(obj->IsHashTable()); 4525 return reinterpret_cast<WeakHashTable*>(obj); 4526 } 4527 4528 // Looks up the value associated with the given key. The hole value is 4529 // returned in case the key is not present. 4530 Object* Lookup(Handle<Object> key); 4531 4532 // Adds (or overwrites) the value associated with the given key. Mapping a 4533 // key to the hole value causes removal of the whole entry. 4534 MUST_USE_RESULT static Handle<WeakHashTable> Put(Handle<WeakHashTable> table, 4535 Handle<Object> key, 4536 Handle<Object> value); 4537 4538 // This function is called when heap verification is turned on. 4539 void Zap(Object* value) { 4540 int capacity = Capacity(); 4541 for (int i = 0; i < capacity; i++) { 4542 set(EntryToIndex(i), value); 4543 set(EntryToValueIndex(i), value); 4544 } 4545 } 4546 4547 private: 4548 friend class MarkCompactCollector; 4549 4550 void AddEntry(int entry, Handle<Object> key, Handle<Object> value); 4551 4552 // Returns the index to the value of an entry. 4553 static inline int EntryToValueIndex(int entry) { 4554 return EntryToIndex(entry) + 1; 4555 } 4556 }; 4557 4558 4559 // JSFunctionResultCache caches results of some JSFunction invocation. 4560 // It is a fixed array with fixed structure: 4561 // [0]: factory function 4562 // [1]: finger index 4563 // [2]: current cache size 4564 // [3]: dummy field. 4565 // The rest of array are key/value pairs. 4566 class JSFunctionResultCache: public FixedArray { 4567 public: 4568 static const int kFactoryIndex = 0; 4569 static const int kFingerIndex = kFactoryIndex + 1; 4570 static const int kCacheSizeIndex = kFingerIndex + 1; 4571 static const int kDummyIndex = kCacheSizeIndex + 1; 4572 static const int kEntriesIndex = kDummyIndex + 1; 4573 4574 static const int kEntrySize = 2; // key + value 4575 4576 static const int kFactoryOffset = kHeaderSize; 4577 static const int kFingerOffset = kFactoryOffset + kPointerSize; 4578 static const int kCacheSizeOffset = kFingerOffset + kPointerSize; 4579 4580 inline void MakeZeroSize(); 4581 inline void Clear(); 4582 4583 inline int size(); 4584 inline void set_size(int size); 4585 inline int finger_index(); 4586 inline void set_finger_index(int finger_index); 4587 4588 // Casting 4589 static inline JSFunctionResultCache* cast(Object* obj); 4590 4591 DECLARE_VERIFIER(JSFunctionResultCache) 4592 }; 4593 4594 4595 // ScopeInfo represents information about different scopes of a source 4596 // program and the allocation of the scope's variables. Scope information 4597 // is stored in a compressed form in ScopeInfo objects and is used 4598 // at runtime (stack dumps, deoptimization, etc.). 4599 4600 // This object provides quick access to scope info details for runtime 4601 // routines. 4602 class ScopeInfo : public FixedArray { 4603 public: 4604 static inline ScopeInfo* cast(Object* object); 4605 4606 // Return the type of this scope. 4607 ScopeType scope_type(); 4608 4609 // Does this scope call eval? 4610 bool CallsEval(); 4611 4612 // Return the strict mode of this scope. 4613 StrictMode strict_mode(); 4614 4615 // Does this scope make a sloppy eval call? 4616 bool CallsSloppyEval() { return CallsEval() && strict_mode() == SLOPPY; } 4617 4618 // Return the total number of locals allocated on the stack and in the 4619 // context. This includes the parameters that are allocated in the context. 4620 int LocalCount(); 4621 4622 // Return the number of stack slots for code. This number consists of two 4623 // parts: 4624 // 1. One stack slot per stack allocated local. 4625 // 2. One stack slot for the function name if it is stack allocated. 4626 int StackSlotCount(); 4627 4628 // Return the number of context slots for code if a context is allocated. This 4629 // number consists of three parts: 4630 // 1. Size of fixed header for every context: Context::MIN_CONTEXT_SLOTS 4631 // 2. One context slot per context allocated local. 4632 // 3. One context slot for the function name if it is context allocated. 4633 // Parameters allocated in the context count as context allocated locals. If 4634 // no contexts are allocated for this scope ContextLength returns 0. 4635 int ContextLength(); 4636 4637 // Is this scope the scope of a named function expression? 4638 bool HasFunctionName(); 4639 4640 // Return if this has context allocated locals. 4641 bool HasHeapAllocatedLocals(); 4642 4643 // Return if contexts are allocated for this scope. 4644 bool HasContext(); 4645 4646 // Return the function_name if present. 4647 String* FunctionName(); 4648 4649 // Return the name of the given parameter. 4650 String* ParameterName(int var); 4651 4652 // Return the name of the given local. 4653 String* LocalName(int var); 4654 4655 // Return the name of the given stack local. 4656 String* StackLocalName(int var); 4657 4658 // Return the name of the given context local. 4659 String* ContextLocalName(int var); 4660 4661 // Return the mode of the given context local. 4662 VariableMode ContextLocalMode(int var); 4663 4664 // Return the initialization flag of the given context local. 4665 InitializationFlag ContextLocalInitFlag(int var); 4666 4667 // Return true if this local was introduced by the compiler, and should not be 4668 // exposed to the user in a debugger. 4669 bool LocalIsSynthetic(int var); 4670 4671 // Lookup support for serialized scope info. Returns the 4672 // the stack slot index for a given slot name if the slot is 4673 // present; otherwise returns a value < 0. The name must be an internalized 4674 // string. 4675 int StackSlotIndex(String* name); 4676 4677 // Lookup support for serialized scope info. Returns the 4678 // context slot index for a given slot name if the slot is present; otherwise 4679 // returns a value < 0. The name must be an internalized string. 4680 // If the slot is present and mode != NULL, sets *mode to the corresponding 4681 // mode for that variable. 4682 static int ContextSlotIndex(Handle<ScopeInfo> scope_info, 4683 Handle<String> name, 4684 VariableMode* mode, 4685 InitializationFlag* init_flag); 4686 4687 // Lookup support for serialized scope info. Returns the 4688 // parameter index for a given parameter name if the parameter is present; 4689 // otherwise returns a value < 0. The name must be an internalized string. 4690 int ParameterIndex(String* name); 4691 4692 // Lookup support for serialized scope info. Returns the function context 4693 // slot index if the function name is present and context-allocated (named 4694 // function expressions, only), otherwise returns a value < 0. The name 4695 // must be an internalized string. 4696 int FunctionContextSlotIndex(String* name, VariableMode* mode); 4697 4698 4699 // Copies all the context locals into an object used to materialize a scope. 4700 static bool CopyContextLocalsToScopeObject(Handle<ScopeInfo> scope_info, 4701 Handle<Context> context, 4702 Handle<JSObject> scope_object); 4703 4704 4705 static Handle<ScopeInfo> Create(Scope* scope, Zone* zone); 4706 4707 // Serializes empty scope info. 4708 static ScopeInfo* Empty(Isolate* isolate); 4709 4710 #ifdef DEBUG 4711 void Print(); 4712 #endif 4713 4714 // The layout of the static part of a ScopeInfo is as follows. Each entry is 4715 // numeric and occupies one array slot. 4716 // 1. A set of properties of the scope 4717 // 2. The number of parameters. This only applies to function scopes. For 4718 // non-function scopes this is 0. 4719 // 3. The number of non-parameter variables allocated on the stack. 4720 // 4. The number of non-parameter and parameter variables allocated in the 4721 // context. 4722 #define FOR_EACH_NUMERIC_FIELD(V) \ 4723 V(Flags) \ 4724 V(ParameterCount) \ 4725 V(StackLocalCount) \ 4726 V(ContextLocalCount) 4727 4728 #define FIELD_ACCESSORS(name) \ 4729 void Set##name(int value) { \ 4730 set(k##name, Smi::FromInt(value)); \ 4731 } \ 4732 int name() { \ 4733 if (length() > 0) { \ 4734 return Smi::cast(get(k##name))->value(); \ 4735 } else { \ 4736 return 0; \ 4737 } \ 4738 } 4739 FOR_EACH_NUMERIC_FIELD(FIELD_ACCESSORS) 4740 #undef FIELD_ACCESSORS 4741 4742 private: 4743 enum { 4744 #define DECL_INDEX(name) k##name, 4745 FOR_EACH_NUMERIC_FIELD(DECL_INDEX) 4746 #undef DECL_INDEX 4747 #undef FOR_EACH_NUMERIC_FIELD 4748 kVariablePartIndex 4749 }; 4750 4751 // The layout of the variable part of a ScopeInfo is as follows: 4752 // 1. ParameterEntries: 4753 // This part stores the names of the parameters for function scopes. One 4754 // slot is used per parameter, so in total this part occupies 4755 // ParameterCount() slots in the array. For other scopes than function 4756 // scopes ParameterCount() is 0. 4757 // 2. StackLocalEntries: 4758 // Contains the names of local variables that are allocated on the stack, 4759 // in increasing order of the stack slot index. One slot is used per stack 4760 // local, so in total this part occupies StackLocalCount() slots in the 4761 // array. 4762 // 3. ContextLocalNameEntries: 4763 // Contains the names of local variables and parameters that are allocated 4764 // in the context. They are stored in increasing order of the context slot 4765 // index starting with Context::MIN_CONTEXT_SLOTS. One slot is used per 4766 // context local, so in total this part occupies ContextLocalCount() slots 4767 // in the array. 4768 // 4. ContextLocalInfoEntries: 4769 // Contains the variable modes and initialization flags corresponding to 4770 // the context locals in ContextLocalNameEntries. One slot is used per 4771 // context local, so in total this part occupies ContextLocalCount() 4772 // slots in the array. 4773 // 5. FunctionNameEntryIndex: 4774 // If the scope belongs to a named function expression this part contains 4775 // information about the function variable. It always occupies two array 4776 // slots: a. The name of the function variable. 4777 // b. The context or stack slot index for the variable. 4778 int ParameterEntriesIndex(); 4779 int StackLocalEntriesIndex(); 4780 int ContextLocalNameEntriesIndex(); 4781 int ContextLocalInfoEntriesIndex(); 4782 int FunctionNameEntryIndex(); 4783 4784 // Location of the function variable for named function expressions. 4785 enum FunctionVariableInfo { 4786 NONE, // No function name present. 4787 STACK, // Function 4788 CONTEXT, 4789 UNUSED 4790 }; 4791 4792 // Properties of scopes. 4793 class ScopeTypeField: public BitField<ScopeType, 0, 3> {}; 4794 class CallsEvalField: public BitField<bool, 3, 1> {}; 4795 class StrictModeField: public BitField<StrictMode, 4, 1> {}; 4796 class FunctionVariableField: public BitField<FunctionVariableInfo, 5, 2> {}; 4797 class FunctionVariableMode: public BitField<VariableMode, 7, 3> {}; 4798 4799 // BitFields representing the encoded information for context locals in the 4800 // ContextLocalInfoEntries part. 4801 class ContextLocalMode: public BitField<VariableMode, 0, 3> {}; 4802 class ContextLocalInitFlag: public BitField<InitializationFlag, 3, 1> {}; 4803 }; 4804 4805 4806 // The cache for maps used by normalized (dictionary mode) objects. 4807 // Such maps do not have property descriptors, so a typical program 4808 // needs very limited number of distinct normalized maps. 4809 class NormalizedMapCache: public FixedArray { 4810 public: 4811 static Handle<NormalizedMapCache> New(Isolate* isolate); 4812 4813 MUST_USE_RESULT MaybeHandle<Map> Get(Handle<Map> fast_map, 4814 PropertyNormalizationMode mode); 4815 void Set(Handle<Map> fast_map, Handle<Map> normalized_map); 4816 4817 void Clear(); 4818 4819 // Casting 4820 static inline NormalizedMapCache* cast(Object* obj); 4821 static inline bool IsNormalizedMapCache(Object* obj); 4822 4823 DECLARE_VERIFIER(NormalizedMapCache) 4824 private: 4825 static const int kEntries = 64; 4826 4827 static inline int GetIndex(Handle<Map> map); 4828 4829 // The following declarations hide base class methods. 4830 Object* get(int index); 4831 void set(int index, Object* value); 4832 }; 4833 4834 4835 // ByteArray represents fixed sized byte arrays. Used for the relocation info 4836 // that is attached to code objects. 4837 class ByteArray: public FixedArrayBase { 4838 public: 4839 inline int Size() { return RoundUp(length() + kHeaderSize, kPointerSize); } 4840 4841 // Setter and getter. 4842 inline byte get(int index); 4843 inline void set(int index, byte value); 4844 4845 // Treat contents as an int array. 4846 inline int get_int(int index); 4847 4848 static int SizeFor(int length) { 4849 return OBJECT_POINTER_ALIGN(kHeaderSize + length); 4850 } 4851 // We use byte arrays for free blocks in the heap. Given a desired size in 4852 // bytes that is a multiple of the word size and big enough to hold a byte 4853 // array, this function returns the number of elements a byte array should 4854 // have. 4855 static int LengthFor(int size_in_bytes) { 4856 ASSERT(IsAligned(size_in_bytes, kPointerSize)); 4857 ASSERT(size_in_bytes >= kHeaderSize); 4858 return size_in_bytes - kHeaderSize; 4859 } 4860 4861 // Returns data start address. 4862 inline Address GetDataStartAddress(); 4863 4864 // Returns a pointer to the ByteArray object for a given data start address. 4865 static inline ByteArray* FromDataStartAddress(Address address); 4866 4867 // Casting. 4868 static inline ByteArray* cast(Object* obj); 4869 4870 // Dispatched behavior. 4871 inline int ByteArraySize() { 4872 return SizeFor(this->length()); 4873 } 4874 DECLARE_PRINTER(ByteArray) 4875 DECLARE_VERIFIER(ByteArray) 4876 4877 // Layout description. 4878 static const int kAlignedSize = OBJECT_POINTER_ALIGN(kHeaderSize); 4879 4880 // Maximal memory consumption for a single ByteArray. 4881 static const int kMaxSize = 512 * MB; 4882 // Maximal length of a single ByteArray. 4883 static const int kMaxLength = kMaxSize - kHeaderSize; 4884 4885 private: 4886 DISALLOW_IMPLICIT_CONSTRUCTORS(ByteArray); 4887 }; 4888 4889 4890 // FreeSpace represents fixed sized areas of the heap that are not currently in 4891 // use. Used by the heap and GC. 4892 class FreeSpace: public HeapObject { 4893 public: 4894 // [size]: size of the free space including the header. 4895 inline int size(); 4896 inline void set_size(int value); 4897 4898 inline int nobarrier_size(); 4899 inline void nobarrier_set_size(int value); 4900 4901 inline int Size() { return size(); } 4902 4903 // Casting. 4904 static inline FreeSpace* cast(Object* obj); 4905 4906 // Dispatched behavior. 4907 DECLARE_PRINTER(FreeSpace) 4908 DECLARE_VERIFIER(FreeSpace) 4909 4910 // Layout description. 4911 // Size is smi tagged when it is stored. 4912 static const int kSizeOffset = HeapObject::kHeaderSize; 4913 static const int kHeaderSize = kSizeOffset + kPointerSize; 4914 4915 static const int kAlignedSize = OBJECT_POINTER_ALIGN(kHeaderSize); 4916 4917 private: 4918 DISALLOW_IMPLICIT_CONSTRUCTORS(FreeSpace); 4919 }; 4920 4921 4922 // V has parameters (Type, type, TYPE, C type, element_size) 4923 #define TYPED_ARRAYS(V) \ 4924 V(Uint8, uint8, UINT8, uint8_t, 1) \ 4925 V(Int8, int8, INT8, int8_t, 1) \ 4926 V(Uint16, uint16, UINT16, uint16_t, 2) \ 4927 V(Int16, int16, INT16, int16_t, 2) \ 4928 V(Uint32, uint32, UINT32, uint32_t, 4) \ 4929 V(Int32, int32, INT32, int32_t, 4) \ 4930 V(Float32, float32, FLOAT32, float, 4) \ 4931 V(Float64, float64, FLOAT64, double, 8) \ 4932 V(Uint8Clamped, uint8_clamped, UINT8_CLAMPED, uint8_t, 1) 4933 4934 4935 4936 // An ExternalArray represents a fixed-size array of primitive values 4937 // which live outside the JavaScript heap. Its subclasses are used to 4938 // implement the CanvasArray types being defined in the WebGL 4939 // specification. As of this writing the first public draft is not yet 4940 // available, but Khronos members can access the draft at: 4941 // https://cvs.khronos.org/svn/repos/3dweb/trunk/doc/spec/WebGL-spec.html 4942 // 4943 // The semantics of these arrays differ from CanvasPixelArray. 4944 // Out-of-range values passed to the setter are converted via a C 4945 // cast, not clamping. Out-of-range indices cause exceptions to be 4946 // raised rather than being silently ignored. 4947 class ExternalArray: public FixedArrayBase { 4948 public: 4949 inline bool is_the_hole(int index) { return false; } 4950 4951 // [external_pointer]: The pointer to the external memory area backing this 4952 // external array. 4953 DECL_ACCESSORS(external_pointer, void) // Pointer to the data store. 4954 4955 // Casting. 4956 static inline ExternalArray* cast(Object* obj); 4957 4958 // Maximal acceptable length for an external array. 4959 static const int kMaxLength = 0x3fffffff; 4960 4961 // ExternalArray headers are not quadword aligned. 4962 static const int kExternalPointerOffset = 4963 POINTER_SIZE_ALIGN(FixedArrayBase::kLengthOffset + kPointerSize); 4964 static const int kHeaderSize = kExternalPointerOffset + kPointerSize; 4965 static const int kAlignedSize = OBJECT_POINTER_ALIGN(kHeaderSize); 4966 4967 private: 4968 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalArray); 4969 }; 4970 4971 4972 // A ExternalUint8ClampedArray represents a fixed-size byte array with special 4973 // semantics used for implementing the CanvasPixelArray object. Please see the 4974 // specification at: 4975 4976 // http://www.whatwg.org/specs/web-apps/current-work/ 4977 // multipage/the-canvas-element.html#canvaspixelarray 4978 // In particular, write access clamps the value written to 0 or 255 if the 4979 // value written is outside this range. 4980 class ExternalUint8ClampedArray: public ExternalArray { 4981 public: 4982 inline uint8_t* external_uint8_clamped_pointer(); 4983 4984 // Setter and getter. 4985 inline uint8_t get_scalar(int index); 4986 static inline Handle<Object> get(Handle<ExternalUint8ClampedArray> array, 4987 int index); 4988 inline void set(int index, uint8_t value); 4989 4990 // This accessor applies the correct conversion from Smi, HeapNumber 4991 // and undefined and clamps the converted value between 0 and 255. 4992 static Handle<Object> SetValue(Handle<ExternalUint8ClampedArray> array, 4993 uint32_t index, 4994 Handle<Object> value); 4995 4996 // Casting. 4997 static inline ExternalUint8ClampedArray* cast(Object* obj); 4998 4999 // Dispatched behavior. 5000 DECLARE_PRINTER(ExternalUint8ClampedArray) 5001 DECLARE_VERIFIER(ExternalUint8ClampedArray) 5002 5003 private: 5004 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalUint8ClampedArray); 5005 }; 5006 5007 5008 class ExternalInt8Array: public ExternalArray { 5009 public: 5010 // Setter and getter. 5011 inline int8_t get_scalar(int index); 5012 static inline Handle<Object> get(Handle<ExternalInt8Array> array, int index); 5013 inline void set(int index, int8_t value); 5014 5015 // This accessor applies the correct conversion from Smi, HeapNumber 5016 // and undefined. 5017 static Handle<Object> SetValue(Handle<ExternalInt8Array> array, 5018 uint32_t index, 5019 Handle<Object> value); 5020 5021 // Casting. 5022 static inline ExternalInt8Array* cast(Object* obj); 5023 5024 // Dispatched behavior. 5025 DECLARE_PRINTER(ExternalInt8Array) 5026 DECLARE_VERIFIER(ExternalInt8Array) 5027 5028 private: 5029 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalInt8Array); 5030 }; 5031 5032 5033 class ExternalUint8Array: public ExternalArray { 5034 public: 5035 // Setter and getter. 5036 inline uint8_t get_scalar(int index); 5037 static inline Handle<Object> get(Handle<ExternalUint8Array> array, int index); 5038 inline void set(int index, uint8_t value); 5039 5040 // This accessor applies the correct conversion from Smi, HeapNumber 5041 // and undefined. 5042 static Handle<Object> SetValue(Handle<ExternalUint8Array> array, 5043 uint32_t index, 5044 Handle<Object> value); 5045 5046 // Casting. 5047 static inline ExternalUint8Array* cast(Object* obj); 5048 5049 // Dispatched behavior. 5050 DECLARE_PRINTER(ExternalUint8Array) 5051 DECLARE_VERIFIER(ExternalUint8Array) 5052 5053 private: 5054 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalUint8Array); 5055 }; 5056 5057 5058 class ExternalInt16Array: public ExternalArray { 5059 public: 5060 // Setter and getter. 5061 inline int16_t get_scalar(int index); 5062 static inline Handle<Object> get(Handle<ExternalInt16Array> array, int index); 5063 inline void set(int index, int16_t value); 5064 5065 // This accessor applies the correct conversion from Smi, HeapNumber 5066 // and undefined. 5067 static Handle<Object> SetValue(Handle<ExternalInt16Array> array, 5068 uint32_t index, 5069 Handle<Object> value); 5070 5071 // Casting. 5072 static inline ExternalInt16Array* cast(Object* obj); 5073 5074 // Dispatched behavior. 5075 DECLARE_PRINTER(ExternalInt16Array) 5076 DECLARE_VERIFIER(ExternalInt16Array) 5077 5078 private: 5079 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalInt16Array); 5080 }; 5081 5082 5083 class ExternalUint16Array: public ExternalArray { 5084 public: 5085 // Setter and getter. 5086 inline uint16_t get_scalar(int index); 5087 static inline Handle<Object> get(Handle<ExternalUint16Array> array, 5088 int index); 5089 inline void set(int index, uint16_t value); 5090 5091 // This accessor applies the correct conversion from Smi, HeapNumber 5092 // and undefined. 5093 static Handle<Object> SetValue(Handle<ExternalUint16Array> array, 5094 uint32_t index, 5095 Handle<Object> value); 5096 5097 // Casting. 5098 static inline ExternalUint16Array* cast(Object* obj); 5099 5100 // Dispatched behavior. 5101 DECLARE_PRINTER(ExternalUint16Array) 5102 DECLARE_VERIFIER(ExternalUint16Array) 5103 5104 private: 5105 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalUint16Array); 5106 }; 5107 5108 5109 class ExternalInt32Array: public ExternalArray { 5110 public: 5111 // Setter and getter. 5112 inline int32_t get_scalar(int index); 5113 static inline Handle<Object> get(Handle<ExternalInt32Array> array, int index); 5114 inline void set(int index, int32_t value); 5115 5116 // This accessor applies the correct conversion from Smi, HeapNumber 5117 // and undefined. 5118 static Handle<Object> SetValue(Handle<ExternalInt32Array> array, 5119 uint32_t index, 5120 Handle<Object> value); 5121 5122 // Casting. 5123 static inline ExternalInt32Array* cast(Object* obj); 5124 5125 // Dispatched behavior. 5126 DECLARE_PRINTER(ExternalInt32Array) 5127 DECLARE_VERIFIER(ExternalInt32Array) 5128 5129 private: 5130 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalInt32Array); 5131 }; 5132 5133 5134 class ExternalUint32Array: public ExternalArray { 5135 public: 5136 // Setter and getter. 5137 inline uint32_t get_scalar(int index); 5138 static inline Handle<Object> get(Handle<ExternalUint32Array> array, 5139 int index); 5140 inline void set(int index, uint32_t value); 5141 5142 // This accessor applies the correct conversion from Smi, HeapNumber 5143 // and undefined. 5144 static Handle<Object> SetValue(Handle<ExternalUint32Array> array, 5145 uint32_t index, 5146 Handle<Object> value); 5147 5148 // Casting. 5149 static inline ExternalUint32Array* cast(Object* obj); 5150 5151 // Dispatched behavior. 5152 DECLARE_PRINTER(ExternalUint32Array) 5153 DECLARE_VERIFIER(ExternalUint32Array) 5154 5155 private: 5156 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalUint32Array); 5157 }; 5158 5159 5160 class ExternalFloat32Array: public ExternalArray { 5161 public: 5162 // Setter and getter. 5163 inline float get_scalar(int index); 5164 static inline Handle<Object> get(Handle<ExternalFloat32Array> array, 5165 int index); 5166 inline void set(int index, float value); 5167 5168 // This accessor applies the correct conversion from Smi, HeapNumber 5169 // and undefined. 5170 static Handle<Object> SetValue(Handle<ExternalFloat32Array> array, 5171 uint32_t index, 5172 Handle<Object> value); 5173 5174 // Casting. 5175 static inline ExternalFloat32Array* cast(Object* obj); 5176 5177 // Dispatched behavior. 5178 DECLARE_PRINTER(ExternalFloat32Array) 5179 DECLARE_VERIFIER(ExternalFloat32Array) 5180 5181 private: 5182 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalFloat32Array); 5183 }; 5184 5185 5186 class ExternalFloat64Array: public ExternalArray { 5187 public: 5188 // Setter and getter. 5189 inline double get_scalar(int index); 5190 static inline Handle<Object> get(Handle<ExternalFloat64Array> array, 5191 int index); 5192 inline void set(int index, double value); 5193 5194 // This accessor applies the correct conversion from Smi, HeapNumber 5195 // and undefined. 5196 static Handle<Object> SetValue(Handle<ExternalFloat64Array> array, 5197 uint32_t index, 5198 Handle<Object> value); 5199 5200 // Casting. 5201 static inline ExternalFloat64Array* cast(Object* obj); 5202 5203 // Dispatched behavior. 5204 DECLARE_PRINTER(ExternalFloat64Array) 5205 DECLARE_VERIFIER(ExternalFloat64Array) 5206 5207 private: 5208 DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalFloat64Array); 5209 }; 5210 5211 5212 class FixedTypedArrayBase: public FixedArrayBase { 5213 public: 5214 // Casting: 5215 static inline FixedTypedArrayBase* cast(Object* obj); 5216 5217 static const int kDataOffset = kHeaderSize; 5218 5219 inline int size(); 5220 5221 inline int TypedArraySize(InstanceType type); 5222 5223 // Use with care: returns raw pointer into heap. 5224 inline void* DataPtr(); 5225 5226 inline int DataSize(); 5227 5228 private: 5229 inline int DataSize(InstanceType type); 5230 5231 DISALLOW_IMPLICIT_CONSTRUCTORS(FixedTypedArrayBase); 5232 }; 5233 5234 5235 template <class Traits> 5236 class FixedTypedArray: public FixedTypedArrayBase { 5237 public: 5238 typedef typename Traits::ElementType ElementType; 5239 static const InstanceType kInstanceType = Traits::kInstanceType; 5240 5241 // Casting: 5242 static inline FixedTypedArray<Traits>* cast(Object* obj); 5243 5244 static inline int ElementOffset(int index) { 5245 return kDataOffset + index * sizeof(ElementType); 5246 } 5247 5248 static inline int SizeFor(int length) { 5249 return ElementOffset(length); 5250 } 5251 5252 inline ElementType get_scalar(int index); 5253 static inline Handle<Object> get(Handle<FixedTypedArray> array, int index); 5254 inline void set(int index, ElementType value); 5255 5256 static inline ElementType from_int(int value); 5257 static inline ElementType from_double(double value); 5258 5259 // This accessor applies the correct conversion from Smi, HeapNumber 5260 // and undefined. 5261 static Handle<Object> SetValue(Handle<FixedTypedArray<Traits> > array, 5262 uint32_t index, 5263 Handle<Object> value); 5264 5265 DECLARE_PRINTER(FixedTypedArray) 5266 DECLARE_VERIFIER(FixedTypedArray) 5267 5268 private: 5269 DISALLOW_IMPLICIT_CONSTRUCTORS(FixedTypedArray); 5270 }; 5271 5272 #define FIXED_TYPED_ARRAY_TRAITS(Type, type, TYPE, elementType, size) \ 5273 class Type##ArrayTraits { \ 5274 public: /* NOLINT */ \ 5275 typedef elementType ElementType; \ 5276 static const InstanceType kInstanceType = FIXED_##TYPE##_ARRAY_TYPE; \ 5277 static const char* Designator() { return #type " array"; } \ 5278 static inline Handle<Object> ToHandle(Isolate* isolate, \ 5279 elementType scalar); \ 5280 static inline elementType defaultValue(); \ 5281 }; \ 5282 \ 5283 typedef FixedTypedArray<Type##ArrayTraits> Fixed##Type##Array; 5284 5285 TYPED_ARRAYS(FIXED_TYPED_ARRAY_TRAITS) 5286 5287 #undef FIXED_TYPED_ARRAY_TRAITS 5288 5289 // DeoptimizationInputData is a fixed array used to hold the deoptimization 5290 // data for code generated by the Hydrogen/Lithium compiler. It also 5291 // contains information about functions that were inlined. If N different 5292 // functions were inlined then first N elements of the literal array will 5293 // contain these functions. 5294 // 5295 // It can be empty. 5296 class DeoptimizationInputData: public FixedArray { 5297 public: 5298 // Layout description. Indices in the array. 5299 static const int kTranslationByteArrayIndex = 0; 5300 static const int kInlinedFunctionCountIndex = 1; 5301 static const int kLiteralArrayIndex = 2; 5302 static const int kOsrAstIdIndex = 3; 5303 static const int kOsrPcOffsetIndex = 4; 5304 static const int kOptimizationIdIndex = 5; 5305 static const int kSharedFunctionInfoIndex = 6; 5306 static const int kFirstDeoptEntryIndex = 7; 5307 5308 // Offsets of deopt entry elements relative to the start of the entry. 5309 static const int kAstIdRawOffset = 0; 5310 static const int kTranslationIndexOffset = 1; 5311 static const int kArgumentsStackHeightOffset = 2; 5312 static const int kPcOffset = 3; 5313 static const int kDeoptEntrySize = 4; 5314 5315 // Simple element accessors. 5316 #define DEFINE_ELEMENT_ACCESSORS(name, type) \ 5317 type* name() { \ 5318 return type::cast(get(k##name##Index)); \ 5319 } \ 5320 void Set##name(type* value) { \ 5321 set(k##name##Index, value); \ 5322 } 5323 5324 DEFINE_ELEMENT_ACCESSORS(TranslationByteArray, ByteArray) 5325 DEFINE_ELEMENT_ACCESSORS(InlinedFunctionCount, Smi) 5326 DEFINE_ELEMENT_ACCESSORS(LiteralArray, FixedArray) 5327 DEFINE_ELEMENT_ACCESSORS(OsrAstId, Smi) 5328 DEFINE_ELEMENT_ACCESSORS(OsrPcOffset, Smi) 5329 DEFINE_ELEMENT_ACCESSORS(OptimizationId, Smi) 5330 DEFINE_ELEMENT_ACCESSORS(SharedFunctionInfo, Object) 5331 5332 #undef DEFINE_ELEMENT_ACCESSORS 5333 5334 // Accessors for elements of the ith deoptimization entry. 5335 #define DEFINE_ENTRY_ACCESSORS(name, type) \ 5336 type* name(int i) { \ 5337 return type::cast(get(IndexForEntry(i) + k##name##Offset)); \ 5338 } \ 5339 void Set##name(int i, type* value) { \ 5340 set(IndexForEntry(i) + k##name##Offset, value); \ 5341 } 5342 5343 DEFINE_ENTRY_ACCESSORS(AstIdRaw, Smi) 5344 DEFINE_ENTRY_ACCESSORS(TranslationIndex, Smi) 5345 DEFINE_ENTRY_ACCESSORS(ArgumentsStackHeight, Smi) 5346 DEFINE_ENTRY_ACCESSORS(Pc, Smi) 5347 5348 #undef DEFINE_ENTRY_ACCESSORS 5349 5350 BailoutId AstId(int i) { 5351 return BailoutId(AstIdRaw(i)->value()); 5352 } 5353 5354 void SetAstId(int i, BailoutId value) { 5355 SetAstIdRaw(i, Smi::FromInt(value.ToInt())); 5356 } 5357 5358 int DeoptCount() { 5359 return (length() - kFirstDeoptEntryIndex) / kDeoptEntrySize; 5360 } 5361 5362 // Allocates a DeoptimizationInputData. 5363 static Handle<DeoptimizationInputData> New(Isolate* isolate, 5364 int deopt_entry_count, 5365 PretenureFlag pretenure); 5366 5367 // Casting. 5368 static inline DeoptimizationInputData* cast(Object* obj); 5369 5370 #ifdef ENABLE_DISASSEMBLER 5371 void DeoptimizationInputDataPrint(FILE* out); 5372 #endif 5373 5374 private: 5375 static int IndexForEntry(int i) { 5376 return kFirstDeoptEntryIndex + (i * kDeoptEntrySize); 5377 } 5378 5379 static int LengthFor(int entry_count) { 5380 return IndexForEntry(entry_count); 5381 } 5382 }; 5383 5384 5385 // DeoptimizationOutputData is a fixed array used to hold the deoptimization 5386 // data for code generated by the full compiler. 5387 // The format of the these objects is 5388 // [i * 2]: Ast ID for ith deoptimization. 5389 // [i * 2 + 1]: PC and state of ith deoptimization 5390 class DeoptimizationOutputData: public FixedArray { 5391 public: 5392 int DeoptPoints() { return length() / 2; } 5393 5394 BailoutId AstId(int index) { 5395 return BailoutId(Smi::cast(get(index * 2))->value()); 5396 } 5397 5398 void SetAstId(int index, BailoutId id) { 5399 set(index * 2, Smi::FromInt(id.ToInt())); 5400 } 5401 5402 Smi* PcAndState(int index) { return Smi::cast(get(1 + index * 2)); } 5403 void SetPcAndState(int index, Smi* offset) { set(1 + index * 2, offset); } 5404 5405 static int LengthOfFixedArray(int deopt_points) { 5406 return deopt_points * 2; 5407 } 5408 5409 // Allocates a DeoptimizationOutputData. 5410 static Handle<DeoptimizationOutputData> New(Isolate* isolate, 5411 int number_of_deopt_points, 5412 PretenureFlag pretenure); 5413 5414 // Casting. 5415 static inline DeoptimizationOutputData* cast(Object* obj); 5416 5417 #if defined(OBJECT_PRINT) || defined(ENABLE_DISASSEMBLER) 5418 void DeoptimizationOutputDataPrint(FILE* out); 5419 #endif 5420 }; 5421 5422 5423 // Forward declaration. 5424 class Cell; 5425 class PropertyCell; 5426 class SafepointEntry; 5427 class TypeFeedbackInfo; 5428 5429 // Code describes objects with on-the-fly generated machine code. 5430 class Code: public HeapObject { 5431 public: 5432 // Opaque data type for encapsulating code flags like kind, inline 5433 // cache state, and arguments count. 5434 typedef uint32_t Flags; 5435 5436 #define NON_IC_KIND_LIST(V) \ 5437 V(FUNCTION) \ 5438 V(OPTIMIZED_FUNCTION) \ 5439 V(STUB) \ 5440 V(HANDLER) \ 5441 V(BUILTIN) \ 5442 V(REGEXP) 5443 5444 #define IC_KIND_LIST(V) \ 5445 V(LOAD_IC) \ 5446 V(KEYED_LOAD_IC) \ 5447 V(CALL_IC) \ 5448 V(STORE_IC) \ 5449 V(KEYED_STORE_IC) \ 5450 V(BINARY_OP_IC) \ 5451 V(COMPARE_IC) \ 5452 V(COMPARE_NIL_IC) \ 5453 V(TO_BOOLEAN_IC) 5454 5455 #define CODE_KIND_LIST(V) \ 5456 NON_IC_KIND_LIST(V) \ 5457 IC_KIND_LIST(V) 5458 5459 enum Kind { 5460 #define DEFINE_CODE_KIND_ENUM(name) name, 5461 CODE_KIND_LIST(DEFINE_CODE_KIND_ENUM) 5462 #undef DEFINE_CODE_KIND_ENUM 5463 NUMBER_OF_KINDS 5464 }; 5465 5466 // No more than 16 kinds. The value is currently encoded in four bits in 5467 // Flags. 5468 STATIC_ASSERT(NUMBER_OF_KINDS <= 16); 5469 5470 static const char* Kind2String(Kind kind); 5471 5472 // Types of stubs. 5473 enum StubType { 5474 NORMAL, 5475 FAST 5476 }; 5477 5478 static const int kPrologueOffsetNotSet = -1; 5479 5480 #ifdef ENABLE_DISASSEMBLER 5481 // Printing 5482 static const char* ICState2String(InlineCacheState state); 5483 static const char* StubType2String(StubType type); 5484 static void PrintExtraICState(FILE* out, Kind kind, ExtraICState extra); 5485 void Disassemble(const char* name, FILE* out = stdout); 5486 #endif // ENABLE_DISASSEMBLER 5487 5488 // [instruction_size]: Size of the native instructions 5489 inline int instruction_size(); 5490 inline void set_instruction_size(int value); 5491 5492 // [relocation_info]: Code relocation information 5493 DECL_ACCESSORS(relocation_info, ByteArray) 5494 void InvalidateRelocation(); 5495 void InvalidateEmbeddedObjects(); 5496 5497 // [handler_table]: Fixed array containing offsets of exception handlers. 5498 DECL_ACCESSORS(handler_table, FixedArray) 5499 5500 // [deoptimization_data]: Array containing data for deopt. 5501 DECL_ACCESSORS(deoptimization_data, FixedArray) 5502 5503 // [raw_type_feedback_info]: This field stores various things, depending on 5504 // the kind of the code object. 5505 // FUNCTION => type feedback information. 5506 // STUB => various things, e.g. a SMI 5507 DECL_ACCESSORS(raw_type_feedback_info, Object) 5508 inline Object* type_feedback_info(); 5509 inline void set_type_feedback_info( 5510 Object* value, WriteBarrierMode mode = UPDATE_WRITE_BARRIER); 5511 inline int stub_info(); 5512 inline void set_stub_info(int info); 5513 5514 // [next_code_link]: Link for lists of optimized or deoptimized code. 5515 // Note that storage for this field is overlapped with typefeedback_info. 5516 DECL_ACCESSORS(next_code_link, Object) 5517 5518 // [gc_metadata]: Field used to hold GC related metadata. The contents of this 5519 // field does not have to be traced during garbage collection since 5520 // it is only used by the garbage collector itself. 5521 DECL_ACCESSORS(gc_metadata, Object) 5522 5523 // [ic_age]: Inline caching age: the value of the Heap::global_ic_age 5524 // at the moment when this object was created. 5525 inline void set_ic_age(int count); 5526 inline int ic_age(); 5527 5528 // [prologue_offset]: Offset of the function prologue, used for aging 5529 // FUNCTIONs and OPTIMIZED_FUNCTIONs. 5530 inline int prologue_offset(); 5531 inline void set_prologue_offset(int offset); 5532 5533 // Unchecked accessors to be used during GC. 5534 inline ByteArray* unchecked_relocation_info(); 5535 5536 inline int relocation_size(); 5537 5538 // [flags]: Various code flags. 5539 inline Flags flags(); 5540 inline void set_flags(Flags flags); 5541 5542 // [flags]: Access to specific code flags. 5543 inline Kind kind(); 5544 inline InlineCacheState ic_state(); // Only valid for IC stubs. 5545 inline ExtraICState extra_ic_state(); // Only valid for IC stubs. 5546 5547 inline StubType type(); // Only valid for monomorphic IC stubs. 5548 5549 // Testers for IC stub kinds. 5550 inline bool is_inline_cache_stub(); 5551 inline bool is_debug_stub(); 5552 inline bool is_handler() { return kind() == HANDLER; } 5553 inline bool is_load_stub() { return kind() == LOAD_IC; } 5554 inline bool is_keyed_load_stub() { return kind() == KEYED_LOAD_IC; } 5555 inline bool is_store_stub() { return kind() == STORE_IC; } 5556 inline bool is_keyed_store_stub() { return kind() == KEYED_STORE_IC; } 5557 inline bool is_call_stub() { return kind() == CALL_IC; } 5558 inline bool is_binary_op_stub() { return kind() == BINARY_OP_IC; } 5559 inline bool is_compare_ic_stub() { return kind() == COMPARE_IC; } 5560 inline bool is_compare_nil_ic_stub() { return kind() == COMPARE_NIL_IC; } 5561 inline bool is_to_boolean_ic_stub() { return kind() == TO_BOOLEAN_IC; } 5562 inline bool is_keyed_stub(); 5563 inline bool is_optimized_code() { return kind() == OPTIMIZED_FUNCTION; } 5564 inline bool is_weak_stub(); 5565 inline void mark_as_weak_stub(); 5566 inline bool is_invalidated_weak_stub(); 5567 inline void mark_as_invalidated_weak_stub(); 5568 5569 inline bool CanBeWeakStub() { 5570 Kind k = kind(); 5571 return (k == LOAD_IC || k == STORE_IC || k == KEYED_LOAD_IC || 5572 k == KEYED_STORE_IC || k == COMPARE_NIL_IC) && 5573 ic_state() == MONOMORPHIC; 5574 } 5575 5576 inline void set_raw_kind_specific_flags1(int value); 5577 inline void set_raw_kind_specific_flags2(int value); 5578 5579 // [major_key]: For kind STUB or BINARY_OP_IC, the major key. 5580 inline int major_key(); 5581 inline void set_major_key(int value); 5582 inline bool has_major_key(); 5583 5584 // For kind STUB or ICs, tells whether or not a code object was generated by 5585 // the optimizing compiler (but it may not be an optimized function). 5586 bool is_crankshafted(); 5587 inline void set_is_crankshafted(bool value); 5588 5589 // [optimizable]: For FUNCTION kind, tells if it is optimizable. 5590 inline bool optimizable(); 5591 inline void set_optimizable(bool value); 5592 5593 // [has_deoptimization_support]: For FUNCTION kind, tells if it has 5594 // deoptimization support. 5595 inline bool has_deoptimization_support(); 5596 inline void set_has_deoptimization_support(bool value); 5597 5598 // [has_debug_break_slots]: For FUNCTION kind, tells if it has 5599 // been compiled with debug break slots. 5600 inline bool has_debug_break_slots(); 5601 inline void set_has_debug_break_slots(bool value); 5602 5603 // [compiled_with_optimizing]: For FUNCTION kind, tells if it has 5604 // been compiled with IsOptimizing set to true. 5605 inline bool is_compiled_optimizable(); 5606 inline void set_compiled_optimizable(bool value); 5607 5608 // [allow_osr_at_loop_nesting_level]: For FUNCTION kind, tells for 5609 // how long the function has been marked for OSR and therefore which 5610 // level of loop nesting we are willing to do on-stack replacement 5611 // for. 5612 inline void set_allow_osr_at_loop_nesting_level(int level); 5613 inline int allow_osr_at_loop_nesting_level(); 5614 5615 // [profiler_ticks]: For FUNCTION kind, tells for how many profiler ticks 5616 // the code object was seen on the stack with no IC patching going on. 5617 inline int profiler_ticks(); 5618 inline void set_profiler_ticks(int ticks); 5619 5620 // [stack_slots]: For kind OPTIMIZED_FUNCTION, the number of stack slots 5621 // reserved in the code prologue. 5622 inline unsigned stack_slots(); 5623 inline void set_stack_slots(unsigned slots); 5624 5625 // [safepoint_table_start]: For kind OPTIMIZED_CODE, the offset in 5626 // the instruction stream where the safepoint table starts. 5627 inline unsigned safepoint_table_offset(); 5628 inline void set_safepoint_table_offset(unsigned offset); 5629 5630 // [back_edge_table_start]: For kind FUNCTION, the offset in the 5631 // instruction stream where the back edge table starts. 5632 inline unsigned back_edge_table_offset(); 5633 inline void set_back_edge_table_offset(unsigned offset); 5634 5635 inline bool back_edges_patched_for_osr(); 5636 inline void set_back_edges_patched_for_osr(bool value); 5637 5638 // [to_boolean_foo]: For kind TO_BOOLEAN_IC tells what state the stub is in. 5639 inline byte to_boolean_state(); 5640 5641 // [has_function_cache]: For kind STUB tells whether there is a function 5642 // cache is passed to the stub. 5643 inline bool has_function_cache(); 5644 inline void set_has_function_cache(bool flag); 5645 5646 5647 // [marked_for_deoptimization]: For kind OPTIMIZED_FUNCTION tells whether 5648 // the code is going to be deoptimized because of dead embedded maps. 5649 inline bool marked_for_deoptimization(); 5650 inline void set_marked_for_deoptimization(bool flag); 5651 5652 // [constant_pool]: The constant pool for this function. 5653 inline ConstantPoolArray* constant_pool(); 5654 inline void set_constant_pool(Object* constant_pool); 5655 5656 // Get the safepoint entry for the given pc. 5657 SafepointEntry GetSafepointEntry(Address pc); 5658 5659 // Find an object in a stub with a specified map 5660 Object* FindNthObject(int n, Map* match_map); 5661 5662 // Find the first allocation site in an IC stub. 5663 AllocationSite* FindFirstAllocationSite(); 5664 5665 // Find the first map in an IC stub. 5666 Map* FindFirstMap(); 5667 void FindAllMaps(MapHandleList* maps); 5668 5669 // Find the first handler in an IC stub. 5670 Code* FindFirstHandler(); 5671 5672 // Find |length| handlers and put them into |code_list|. Returns false if not 5673 // enough handlers can be found. 5674 bool FindHandlers(CodeHandleList* code_list, int length = -1); 5675 5676 // Find the first name in an IC stub. 5677 Name* FindFirstName(); 5678 5679 class FindAndReplacePattern; 5680 // For each (map-to-find, object-to-replace) pair in the pattern, this 5681 // function replaces the corresponding placeholder in the code with the 5682 // object-to-replace. The function assumes that pairs in the pattern come in 5683 // the same order as the placeholders in the code. 5684 void FindAndReplace(const FindAndReplacePattern& pattern); 5685 5686 // The entire code object including its header is copied verbatim to the 5687 // snapshot so that it can be written in one, fast, memcpy during 5688 // deserialization. The deserializer will overwrite some pointers, rather 5689 // like a runtime linker, but the random allocation addresses used in the 5690 // mksnapshot process would still be present in the unlinked snapshot data, 5691 // which would make snapshot production non-reproducible. This method wipes 5692 // out the to-be-overwritten header data for reproducible snapshots. 5693 inline void WipeOutHeader(); 5694 5695 // Flags operations. 5696 static inline Flags ComputeFlags( 5697 Kind kind, 5698 InlineCacheState ic_state = UNINITIALIZED, 5699 ExtraICState extra_ic_state = kNoExtraICState, 5700 StubType type = NORMAL, 5701 InlineCacheHolderFlag holder = OWN_MAP); 5702 5703 static inline Flags ComputeMonomorphicFlags( 5704 Kind kind, 5705 ExtraICState extra_ic_state = kNoExtraICState, 5706 InlineCacheHolderFlag holder = OWN_MAP, 5707 StubType type = NORMAL); 5708 5709 static inline Flags ComputeHandlerFlags( 5710 Kind handler_kind, 5711 StubType type = NORMAL, 5712 InlineCacheHolderFlag holder = OWN_MAP); 5713 5714 static inline InlineCacheState ExtractICStateFromFlags(Flags flags); 5715 static inline StubType ExtractTypeFromFlags(Flags flags); 5716 static inline Kind ExtractKindFromFlags(Flags flags); 5717 static inline InlineCacheHolderFlag ExtractCacheHolderFromFlags(Flags flags); 5718 static inline ExtraICState ExtractExtraICStateFromFlags(Flags flags); 5719 5720 static inline Flags RemoveTypeFromFlags(Flags flags); 5721 5722 // Convert a target address into a code object. 5723 static inline Code* GetCodeFromTargetAddress(Address address); 5724 5725 // Convert an entry address into an object. 5726 static inline Object* GetObjectFromEntryAddress(Address location_of_address); 5727 5728 // Returns the address of the first instruction. 5729 inline byte* instruction_start(); 5730 5731 // Returns the address right after the last instruction. 5732 inline byte* instruction_end(); 5733 5734 // Returns the size of the instructions, padding, and relocation information. 5735 inline int body_size(); 5736 5737 // Returns the address of the first relocation info (read backwards!). 5738 inline byte* relocation_start(); 5739 5740 // Code entry point. 5741 inline byte* entry(); 5742 5743 // Returns true if pc is inside this object's instructions. 5744 inline bool contains(byte* pc); 5745 5746 // Relocate the code by delta bytes. Called to signal that this code 5747 // object has been moved by delta bytes. 5748 void Relocate(intptr_t delta); 5749 5750 // Migrate code described by desc. 5751 void CopyFrom(const CodeDesc& desc); 5752 5753 // Returns the object size for a given body (used for allocation). 5754 static int SizeFor(int body_size) { 5755 ASSERT_SIZE_TAG_ALIGNED(body_size); 5756 return RoundUp(kHeaderSize + body_size, kCodeAlignment); 5757 } 5758 5759 // Calculate the size of the code object to report for log events. This takes 5760 // the layout of the code object into account. 5761 int ExecutableSize() { 5762 // Check that the assumptions about the layout of the code object holds. 5763 ASSERT_EQ(static_cast<int>(instruction_start() - address()), 5764 Code::kHeaderSize); 5765 return instruction_size() + Code::kHeaderSize; 5766 } 5767 5768 // Locating source position. 5769 int SourcePosition(Address pc); 5770 int SourceStatementPosition(Address pc); 5771 5772 // Casting. 5773 static inline Code* cast(Object* obj); 5774 5775 // Dispatched behavior. 5776 int CodeSize() { return SizeFor(body_size()); } 5777 inline void CodeIterateBody(ObjectVisitor* v); 5778 5779 template<typename StaticVisitor> 5780 inline void CodeIterateBody(Heap* heap); 5781 5782 DECLARE_PRINTER(Code) 5783 DECLARE_VERIFIER(Code) 5784 5785 void ClearInlineCaches(); 5786 void ClearInlineCaches(Kind kind); 5787 5788 BailoutId TranslatePcOffsetToAstId(uint32_t pc_offset); 5789 uint32_t TranslateAstIdToPcOffset(BailoutId ast_id); 5790 5791 #define DECLARE_CODE_AGE_ENUM(X) k##X##CodeAge, 5792 enum Age { 5793 kNotExecutedCodeAge = -2, 5794 kExecutedOnceCodeAge = -1, 5795 kNoAgeCodeAge = 0, 5796 CODE_AGE_LIST(DECLARE_CODE_AGE_ENUM) 5797 kAfterLastCodeAge, 5798 kFirstCodeAge = kNotExecutedCodeAge, 5799 kLastCodeAge = kAfterLastCodeAge - 1, 5800 kCodeAgeCount = kAfterLastCodeAge - kNotExecutedCodeAge - 1, 5801 kIsOldCodeAge = kSexagenarianCodeAge, 5802 kPreAgedCodeAge = kIsOldCodeAge - 1 5803 }; 5804 #undef DECLARE_CODE_AGE_ENUM 5805 5806 // Code aging. Indicates how many full GCs this code has survived without 5807 // being entered through the prologue. Used to determine when it is 5808 // relatively safe to flush this code object and replace it with the lazy 5809 // compilation stub. 5810 static void MakeCodeAgeSequenceYoung(byte* sequence, Isolate* isolate); 5811 static void MarkCodeAsExecuted(byte* sequence, Isolate* isolate); 5812 void MakeOlder(MarkingParity); 5813 static bool IsYoungSequence(Isolate* isolate, byte* sequence); 5814 bool IsOld(); 5815 Age GetAge(); 5816 // Gets the raw code age, including psuedo code-age values such as 5817 // kNotExecutedCodeAge and kExecutedOnceCodeAge. 5818 Age GetRawAge(); 5819 static inline Code* GetPreAgedCodeAgeStub(Isolate* isolate) { 5820 return GetCodeAgeStub(isolate, kNotExecutedCodeAge, NO_MARKING_PARITY); 5821 } 5822 5823 void PrintDeoptLocation(FILE* out, int bailout_id); 5824 bool CanDeoptAt(Address pc); 5825 5826 #ifdef VERIFY_HEAP 5827 void VerifyEmbeddedObjectsDependency(); 5828 #endif 5829 5830 inline bool CanContainWeakObjects() { 5831 return is_optimized_code() || is_weak_stub(); 5832 } 5833 5834 inline bool IsWeakObject(Object* object) { 5835 return (is_optimized_code() && IsWeakObjectInOptimizedCode(object)) || 5836 (is_weak_stub() && IsWeakObjectInIC(object)); 5837 } 5838 5839 static inline bool IsWeakObjectInOptimizedCode(Object* object); 5840 static inline bool IsWeakObjectInIC(Object* object); 5841 5842 // Max loop nesting marker used to postpose OSR. We don't take loop 5843 // nesting that is deeper than 5 levels into account. 5844 static const int kMaxLoopNestingMarker = 6; 5845 5846 // Layout description. 5847 static const int kInstructionSizeOffset = HeapObject::kHeaderSize; 5848 static const int kRelocationInfoOffset = kInstructionSizeOffset + kIntSize; 5849 static const int kHandlerTableOffset = kRelocationInfoOffset + kPointerSize; 5850 static const int kDeoptimizationDataOffset = 5851 kHandlerTableOffset + kPointerSize; 5852 static const int kTypeFeedbackInfoOffset = 5853 kDeoptimizationDataOffset + kPointerSize; 5854 static const int kNextCodeLinkOffset = kTypeFeedbackInfoOffset + kPointerSize; 5855 static const int kGCMetadataOffset = kNextCodeLinkOffset + kPointerSize; 5856 static const int kICAgeOffset = 5857 kGCMetadataOffset + kPointerSize; 5858 static const int kFlagsOffset = kICAgeOffset + kIntSize; 5859 static const int kKindSpecificFlags1Offset = kFlagsOffset + kIntSize; 5860 static const int kKindSpecificFlags2Offset = 5861 kKindSpecificFlags1Offset + kIntSize; 5862 // Note: We might be able to squeeze this into the flags above. 5863 static const int kPrologueOffset = kKindSpecificFlags2Offset + kIntSize; 5864 static const int kConstantPoolOffset = kPrologueOffset + kPointerSize; 5865 5866 static const int kHeaderPaddingStart = kConstantPoolOffset + kIntSize; 5867 5868 // Add padding to align the instruction start following right after 5869 // the Code object header. 5870 static const int kHeaderSize = 5871 (kHeaderPaddingStart + kCodeAlignmentMask) & ~kCodeAlignmentMask; 5872 5873 // Byte offsets within kKindSpecificFlags1Offset. 5874 static const int kOptimizableOffset = kKindSpecificFlags1Offset; 5875 5876 static const int kFullCodeFlags = kOptimizableOffset + 1; 5877 class FullCodeFlagsHasDeoptimizationSupportField: 5878 public BitField<bool, 0, 1> {}; // NOLINT 5879 class FullCodeFlagsHasDebugBreakSlotsField: public BitField<bool, 1, 1> {}; 5880 class FullCodeFlagsIsCompiledOptimizable: public BitField<bool, 2, 1> {}; 5881 5882 static const int kAllowOSRAtLoopNestingLevelOffset = kFullCodeFlags + 1; 5883 static const int kProfilerTicksOffset = kAllowOSRAtLoopNestingLevelOffset + 1; 5884 5885 // Flags layout. BitField<type, shift, size>. 5886 class ICStateField: public BitField<InlineCacheState, 0, 3> {}; 5887 class TypeField: public BitField<StubType, 3, 1> {}; 5888 class CacheHolderField: public BitField<InlineCacheHolderFlag, 5, 1> {}; 5889 class KindField: public BitField<Kind, 6, 4> {}; 5890 // TODO(bmeurer): Bit 10 is available for free use. :-) 5891 class ExtraICStateField: public BitField<ExtraICState, 11, 5892 PlatformSmiTagging::kSmiValueSize - 11 + 1> {}; // NOLINT 5893 5894 // KindSpecificFlags1 layout (STUB and OPTIMIZED_FUNCTION) 5895 static const int kStackSlotsFirstBit = 0; 5896 static const int kStackSlotsBitCount = 24; 5897 static const int kHasFunctionCacheFirstBit = 5898 kStackSlotsFirstBit + kStackSlotsBitCount; 5899 static const int kHasFunctionCacheBitCount = 1; 5900 static const int kMarkedForDeoptimizationFirstBit = 5901 kStackSlotsFirstBit + kStackSlotsBitCount + 1; 5902 static const int kMarkedForDeoptimizationBitCount = 1; 5903 static const int kWeakStubFirstBit = 5904 kMarkedForDeoptimizationFirstBit + kMarkedForDeoptimizationBitCount; 5905 static const int kWeakStubBitCount = 1; 5906 static const int kInvalidatedWeakStubFirstBit = 5907 kWeakStubFirstBit + kWeakStubBitCount; 5908 static const int kInvalidatedWeakStubBitCount = 1; 5909 5910 STATIC_ASSERT(kStackSlotsFirstBit + kStackSlotsBitCount <= 32); 5911 STATIC_ASSERT(kHasFunctionCacheFirstBit + kHasFunctionCacheBitCount <= 32); 5912 STATIC_ASSERT(kInvalidatedWeakStubFirstBit + 5913 kInvalidatedWeakStubBitCount <= 32); 5914 5915 class StackSlotsField: public BitField<int, 5916 kStackSlotsFirstBit, kStackSlotsBitCount> {}; // NOLINT 5917 class HasFunctionCacheField: public BitField<bool, 5918 kHasFunctionCacheFirstBit, kHasFunctionCacheBitCount> {}; // NOLINT 5919 class MarkedForDeoptimizationField: public BitField<bool, 5920 kMarkedForDeoptimizationFirstBit, 5921 kMarkedForDeoptimizationBitCount> {}; // NOLINT 5922 class WeakStubField: public BitField<bool, 5923 kWeakStubFirstBit, 5924 kWeakStubBitCount> {}; // NOLINT 5925 class InvalidatedWeakStubField: public BitField<bool, 5926 kInvalidatedWeakStubFirstBit, 5927 kInvalidatedWeakStubBitCount> {}; // NOLINT 5928 5929 // KindSpecificFlags2 layout (ALL) 5930 static const int kIsCrankshaftedBit = 0; 5931 class IsCrankshaftedField: public BitField<bool, 5932 kIsCrankshaftedBit, 1> {}; // NOLINT 5933 5934 // KindSpecificFlags2 layout (STUB and OPTIMIZED_FUNCTION) 5935 static const int kStubMajorKeyFirstBit = kIsCrankshaftedBit + 1; 5936 static const int kSafepointTableOffsetFirstBit = 5937 kStubMajorKeyFirstBit + kStubMajorKeyBits; 5938 static const int kSafepointTableOffsetBitCount = 24; 5939 5940 STATIC_ASSERT(kStubMajorKeyFirstBit + kStubMajorKeyBits <= 32); 5941 STATIC_ASSERT(kSafepointTableOffsetFirstBit + 5942 kSafepointTableOffsetBitCount <= 32); 5943 STATIC_ASSERT(1 + kStubMajorKeyBits + 5944 kSafepointTableOffsetBitCount <= 32); 5945 5946 class SafepointTableOffsetField: public BitField<int, 5947 kSafepointTableOffsetFirstBit, 5948 kSafepointTableOffsetBitCount> {}; // NOLINT 5949 class StubMajorKeyField: public BitField<int, 5950 kStubMajorKeyFirstBit, kStubMajorKeyBits> {}; // NOLINT 5951 5952 // KindSpecificFlags2 layout (FUNCTION) 5953 class BackEdgeTableOffsetField: public BitField<int, 5954 kIsCrankshaftedBit + 1, 29> {}; // NOLINT 5955 class BackEdgesPatchedForOSRField: public BitField<bool, 5956 kIsCrankshaftedBit + 1 + 29, 1> {}; // NOLINT 5957 5958 static const int kArgumentsBits = 16; 5959 static const int kMaxArguments = (1 << kArgumentsBits) - 1; 5960 5961 // This constant should be encodable in an ARM instruction. 5962 static const int kFlagsNotUsedInLookup = 5963 TypeField::kMask | CacheHolderField::kMask; 5964 5965 private: 5966 friend class RelocIterator; 5967 friend class Deoptimizer; // For FindCodeAgeSequence. 5968 5969 void ClearInlineCaches(Kind* kind); 5970 5971 // Code aging 5972 byte* FindCodeAgeSequence(); 5973 static void GetCodeAgeAndParity(Code* code, Age* age, 5974 MarkingParity* parity); 5975 static void GetCodeAgeAndParity(Isolate* isolate, byte* sequence, Age* age, 5976 MarkingParity* parity); 5977 static Code* GetCodeAgeStub(Isolate* isolate, Age age, MarkingParity parity); 5978 5979 // Code aging -- platform-specific 5980 static void PatchPlatformCodeAge(Isolate* isolate, 5981 byte* sequence, Age age, 5982 MarkingParity parity); 5983 5984 DISALLOW_IMPLICIT_CONSTRUCTORS(Code); 5985 }; 5986 5987 5988 class CompilationInfo; 5989 5990 // This class describes the layout of dependent codes array of a map. The 5991 // array is partitioned into several groups of dependent codes. Each group 5992 // contains codes with the same dependency on the map. The array has the 5993 // following layout for n dependency groups: 5994 // 5995 // +----+----+-----+----+---------+----------+-----+---------+-----------+ 5996 // | C1 | C2 | ... | Cn | group 1 | group 2 | ... | group n | undefined | 5997 // +----+----+-----+----+---------+----------+-----+---------+-----------+ 5998 // 5999 // The first n elements are Smis, each of them specifies the number of codes 6000 // in the corresponding group. The subsequent elements contain grouped code 6001 // objects. The suffix of the array can be filled with the undefined value if 6002 // the number of codes is less than the length of the array. The order of the 6003 // code objects within a group is not preserved. 6004 // 6005 // All code indexes used in the class are counted starting from the first 6006 // code object of the first group. In other words, code index 0 corresponds 6007 // to array index n = kCodesStartIndex. 6008 6009 class DependentCode: public FixedArray { 6010 public: 6011 enum DependencyGroup { 6012 // Group of IC stubs that weakly embed this map and depend on being 6013 // invalidated when the map is garbage collected. Dependent IC stubs form 6014 // a linked list. This group stores only the head of the list. This means 6015 // that the number_of_entries(kWeakICGroup) is 0 or 1. 6016 kWeakICGroup, 6017 // Group of code that weakly embed this map and depend on being 6018 // deoptimized when the map is garbage collected. 6019 kWeakCodeGroup, 6020 // Group of code that embed a transition to this map, and depend on being 6021 // deoptimized when the transition is replaced by a new version. 6022 kTransitionGroup, 6023 // Group of code that omit run-time prototype checks for prototypes 6024 // described by this map. The group is deoptimized whenever an object 6025 // described by this map changes shape (and transitions to a new map), 6026 // possibly invalidating the assumptions embedded in the code. 6027 kPrototypeCheckGroup, 6028 // Group of code that depends on elements not being added to objects with 6029 // this map. 6030 kElementsCantBeAddedGroup, 6031 // Group of code that depends on global property values in property cells 6032 // not being changed. 6033 kPropertyCellChangedGroup, 6034 // Group of code that omit run-time type checks for the field(s) introduced 6035 // by this map. 6036 kFieldTypeGroup, 6037 // Group of code that omit run-time type checks for initial maps of 6038 // constructors. 6039 kInitialMapChangedGroup, 6040 // Group of code that depends on tenuring information in AllocationSites 6041 // not being changed. 6042 kAllocationSiteTenuringChangedGroup, 6043 // Group of code that depends on element transition information in 6044 // AllocationSites not being changed. 6045 kAllocationSiteTransitionChangedGroup, 6046 kGroupCount = kAllocationSiteTransitionChangedGroup + 1 6047 }; 6048 6049 // Array for holding the index of the first code object of each group. 6050 // The last element stores the total number of code objects. 6051 class GroupStartIndexes { 6052 public: 6053 explicit GroupStartIndexes(DependentCode* entries); 6054 void Recompute(DependentCode* entries); 6055 int at(int i) { return start_indexes_[i]; } 6056 int number_of_entries() { return start_indexes_[kGroupCount]; } 6057 private: 6058 int start_indexes_[kGroupCount + 1]; 6059 }; 6060 6061 bool Contains(DependencyGroup group, Code* code); 6062 static Handle<DependentCode> Insert(Handle<DependentCode> entries, 6063 DependencyGroup group, 6064 Handle<Object> object); 6065 void UpdateToFinishedCode(DependencyGroup group, 6066 CompilationInfo* info, 6067 Code* code); 6068 void RemoveCompilationInfo(DependentCode::DependencyGroup group, 6069 CompilationInfo* info); 6070 6071 void DeoptimizeDependentCodeGroup(Isolate* isolate, 6072 DependentCode::DependencyGroup group); 6073 6074 bool MarkCodeForDeoptimization(Isolate* isolate, 6075 DependentCode::DependencyGroup group); 6076 void AddToDependentICList(Handle<Code> stub); 6077 6078 // The following low-level accessors should only be used by this class 6079 // and the mark compact collector. 6080 inline int number_of_entries(DependencyGroup group); 6081 inline void set_number_of_entries(DependencyGroup group, int value); 6082 inline bool is_code_at(int i); 6083 inline Code* code_at(int i); 6084 inline CompilationInfo* compilation_info_at(int i); 6085 inline void set_object_at(int i, Object* object); 6086 inline Object** slot_at(int i); 6087 inline Object* object_at(int i); 6088 inline void clear_at(int i); 6089 inline void copy(int from, int to); 6090 static inline DependentCode* cast(Object* object); 6091 6092 static DependentCode* ForObject(Handle<HeapObject> object, 6093 DependencyGroup group); 6094 6095 private: 6096 // Make a room at the end of the given group by moving out the first 6097 // code objects of the subsequent groups. 6098 inline void ExtendGroup(DependencyGroup group); 6099 static const int kCodesStartIndex = kGroupCount; 6100 }; 6101 6102 6103 // All heap objects have a Map that describes their structure. 6104 // A Map contains information about: 6105 // - Size information about the object 6106 // - How to iterate over an object (for garbage collection) 6107 class Map: public HeapObject { 6108 public: 6109 // Instance size. 6110 // Size in bytes or kVariableSizeSentinel if instances do not have 6111 // a fixed size. 6112 inline int instance_size(); 6113 inline void set_instance_size(int value); 6114 6115 // Count of properties allocated in the object. 6116 inline int inobject_properties(); 6117 inline void set_inobject_properties(int value); 6118 6119 // Count of property fields pre-allocated in the object when first allocated. 6120 inline int pre_allocated_property_fields(); 6121 inline void set_pre_allocated_property_fields(int value); 6122 6123 // Instance type. 6124 inline InstanceType instance_type(); 6125 inline void set_instance_type(InstanceType value); 6126 6127 // Tells how many unused property fields are available in the 6128 // instance (only used for JSObject in fast mode). 6129 inline int unused_property_fields(); 6130 inline void set_unused_property_fields(int value); 6131 6132 // Bit field. 6133 inline byte bit_field(); 6134 inline void set_bit_field(byte value); 6135 6136 // Bit field 2. 6137 inline byte bit_field2(); 6138 inline void set_bit_field2(byte value); 6139 6140 // Bit field 3. 6141 inline uint32_t bit_field3(); 6142 inline void set_bit_field3(uint32_t bits); 6143 6144 class EnumLengthBits: public BitField<int, 6145 0, kDescriptorIndexBitCount> {}; // NOLINT 6146 class NumberOfOwnDescriptorsBits: public BitField<