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Diffstat (limited to 'src/3rdparty/v8/src/objects.h')
| -rw-r--r-- | src/3rdparty/v8/src/objects.h | 9150 |
1 files changed, 0 insertions, 9150 deletions
diff --git a/src/3rdparty/v8/src/objects.h b/src/3rdparty/v8/src/objects.h deleted file mode 100644 index 07bb288..0000000 --- a/src/3rdparty/v8/src/objects.h +++ /dev/null @@ -1,9150 +0,0 @@ -// Copyright 2012 the V8 project authors. All rights reserved. -// Redistribution and use in source and binary forms, with or without -// modification, are permitted provided that the following conditions are -// met: -// -// * Redistributions of source code must retain the above copyright -// notice, this list of conditions and the following disclaimer. -// * Redistributions in binary form must reproduce the above -// copyright notice, this list of conditions and the following -// disclaimer in the documentation and/or other materials provided -// with the distribution. -// * Neither the name of Google Inc. nor the names of its -// contributors may be used to endorse or promote products derived -// from this software without specific prior written permission. -// -// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - -#ifndef V8_OBJECTS_H_ -#define V8_OBJECTS_H_ - -#include "allocation.h" -#include "builtins.h" -#include "elements-kind.h" -#include "list.h" -#include "property-details.h" -#include "smart-pointers.h" -#include "unicode-inl.h" -#if V8_TARGET_ARCH_ARM -#include "arm/constants-arm.h" -#elif V8_TARGET_ARCH_MIPS -#include "mips/constants-mips.h" -#endif -#include "v8checks.h" -#include "zone.h" - - -// -// Most object types in the V8 JavaScript are described in this file. -// -// Inheritance hierarchy: -// - MaybeObject (an object or a failure) -// - Failure (immediate for marking failed operation) -// - Object -// - Smi (immediate small integer) -// - HeapObject (superclass for everything allocated in the heap) -// - JSReceiver (suitable for property access) -// - JSObject -// - JSArray -// - JSSet -// - JSMap -// - JSWeakMap -// - JSRegExp -// - JSFunction -// - JSModule -// - GlobalObject -// - JSGlobalObject -// - JSBuiltinsObject -// - JSGlobalProxy -// - JSValue -// - JSDate -// - JSMessageObject -// - JSProxy -// - JSFunctionProxy -// - FixedArrayBase -// - ByteArray -// - FixedArray -// - DescriptorArray -// - HashTable -// - Dictionary -// - StringTable -// - CompilationCacheTable -// - CodeCacheHashTable -// - MapCache -// - Context -// - JSFunctionResultCache -// - ScopeInfo -// - TransitionArray -// - FixedDoubleArray -// - ExternalArray -// - ExternalPixelArray -// - ExternalByteArray -// - ExternalUnsignedByteArray -// - ExternalShortArray -// - ExternalUnsignedShortArray -// - ExternalIntArray -// - ExternalUnsignedIntArray -// - ExternalFloatArray -// - Name -// - String -// - SeqString -// - SeqOneByteString -// - SeqTwoByteString -// - SlicedString -// - ConsString -// - ExternalString -// - ExternalAsciiString -// - ExternalTwoByteString -// - InternalizedString -// - SeqInternalizedString -// - SeqOneByteInternalizedString -// - SeqTwoByteInternalizedString -// - ConsInternalizedString -// - ExternalInternalizedString -// - ExternalAsciiInternalizedString -// - ExternalTwoByteInternalizedString -// - Symbol -// - HeapNumber -// - Code -// - Map -// - Oddball -// - Foreign -// - SharedFunctionInfo -// - Struct -// - DeclaredAccessorDescriptor -// - AccessorInfo -// - DeclaredAccessorInfo -// - ExecutableAccessorInfo -// - AccessorPair -// - AccessCheckInfo -// - InterceptorInfo -// - CallHandlerInfo -// - TemplateInfo -// - FunctionTemplateInfo -// - ObjectTemplateInfo -// - Script -// - SignatureInfo -// - TypeSwitchInfo -// - DebugInfo -// - BreakPointInfo -// - CodeCache -// -// Formats of Object*: -// Smi: [31 bit signed int] 0 -// HeapObject: [32 bit direct pointer] (4 byte aligned) | 01 -// Failure: [30 bit signed int] 11 - -namespace v8 { -namespace internal { - -enum CompareMapMode { - REQUIRE_EXACT_MAP, - ALLOW_ELEMENT_TRANSITION_MAPS -}; - -enum KeyedAccessGrowMode { - DO_NOT_ALLOW_JSARRAY_GROWTH, - ALLOW_JSARRAY_GROWTH -}; - -// Setter that skips the write barrier if mode is SKIP_WRITE_BARRIER. -enum WriteBarrierMode { SKIP_WRITE_BARRIER, UPDATE_WRITE_BARRIER }; - - -// PropertyNormalizationMode is used to specify whether to keep -// inobject properties when normalizing properties of a JSObject. -enum PropertyNormalizationMode { - CLEAR_INOBJECT_PROPERTIES, - KEEP_INOBJECT_PROPERTIES -}; - - -// NormalizedMapSharingMode is used to specify whether a map may be shared -// by different objects with normalized properties. -enum NormalizedMapSharingMode { - UNIQUE_NORMALIZED_MAP, - SHARED_NORMALIZED_MAP -}; - - -// Indicates whether a get method should implicitly create the object looked up. -enum CreationFlag { - ALLOW_CREATION, - OMIT_CREATION -}; - - -// Indicates whether transitions can be added to a source map or not. -enum TransitionFlag { - INSERT_TRANSITION, - OMIT_TRANSITION -}; - - -enum DebugExtraICState { - DEBUG_BREAK, - DEBUG_PREPARE_STEP_IN -}; - - -// Indicates whether the transition is simple: the target map of the transition -// either extends the current map with a new property, or it modifies the -// property that was added last to the current map. -enum SimpleTransitionFlag { - SIMPLE_TRANSITION, - FULL_TRANSITION -}; - - -// Indicates whether we are only interested in the descriptors of a particular -// map, or in all descriptors in the descriptor array. -enum DescriptorFlag { - ALL_DESCRIPTORS, - OWN_DESCRIPTORS -}; - -// The GC maintains a bit of information, the MarkingParity, which toggles -// from odd to even and back every time marking is completed. Incremental -// marking can visit an object twice during a marking phase, so algorithms that -// that piggy-back on marking can use the parity to ensure that they only -// perform an operation on an object once per marking phase: they record the -// MarkingParity when they visit an object, and only re-visit the object when it -// is marked again and the MarkingParity changes. -enum MarkingParity { - NO_MARKING_PARITY, - ODD_MARKING_PARITY, - EVEN_MARKING_PARITY -}; - -// Instance size sentinel for objects of variable size. -const int kVariableSizeSentinel = 0; - -const int kStubMajorKeyBits = 6; -const int kStubMinorKeyBits = kBitsPerInt - kSmiTagSize - kStubMajorKeyBits; - -// All Maps have a field instance_type containing a InstanceType. -// It describes the type of the instances. -// -// As an example, a JavaScript object is a heap object and its map -// instance_type is JS_OBJECT_TYPE. -// -// The names of the string instance types are intended to systematically -// mirror their encoding in the instance_type field of the map. The default -// encoding is considered TWO_BYTE. It is not mentioned in the name. ASCII -// encoding is mentioned explicitly in the name. Likewise, the default -// representation is considered sequential. It is not mentioned in the -// name. The other representations (e.g. CONS, EXTERNAL) are explicitly -// mentioned. Finally, the string is either a STRING_TYPE (if it is a normal -// string) or a INTERNALIZED_STRING_TYPE (if it is a internalized string). -// -// NOTE: The following things are some that depend on the string types having -// instance_types that are less than those of all other types: -// HeapObject::Size, HeapObject::IterateBody, the typeof operator, and -// Object::IsString. -// -// NOTE: Everything following JS_VALUE_TYPE is considered a -// JSObject for GC purposes. The first four entries here have typeof -// 'object', whereas JS_FUNCTION_TYPE has typeof 'function'. -#define INSTANCE_TYPE_LIST_ALL(V) \ - V(STRING_TYPE) \ - V(ASCII_STRING_TYPE) \ - V(CONS_STRING_TYPE) \ - V(CONS_ASCII_STRING_TYPE) \ - V(SLICED_STRING_TYPE) \ - V(EXTERNAL_STRING_TYPE) \ - V(EXTERNAL_ASCII_STRING_TYPE) \ - V(EXTERNAL_STRING_WITH_ASCII_DATA_TYPE) \ - V(SHORT_EXTERNAL_STRING_TYPE) \ - V(SHORT_EXTERNAL_ASCII_STRING_TYPE) \ - V(SHORT_EXTERNAL_STRING_WITH_ASCII_DATA_TYPE) \ - \ - V(INTERNALIZED_STRING_TYPE) \ - V(ASCII_INTERNALIZED_STRING_TYPE) \ - V(CONS_INTERNALIZED_STRING_TYPE) \ - V(CONS_ASCII_INTERNALIZED_STRING_TYPE) \ - V(EXTERNAL_INTERNALIZED_STRING_TYPE) \ - V(EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE) \ - V(EXTERNAL_INTERNALIZED_STRING_WITH_ASCII_DATA_TYPE) \ - V(SHORT_EXTERNAL_INTERNALIZED_STRING_TYPE) \ - V(SHORT_EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE) \ - V(SHORT_EXTERNAL_INTERNALIZED_STRING_WITH_ASCII_DATA_TYPE) \ - \ - V(SYMBOL_TYPE) \ - V(MAP_TYPE) \ - V(CODE_TYPE) \ - V(ODDBALL_TYPE) \ - V(JS_GLOBAL_PROPERTY_CELL_TYPE) \ - \ - V(HEAP_NUMBER_TYPE) \ - V(FOREIGN_TYPE) \ - V(BYTE_ARRAY_TYPE) \ - V(FREE_SPACE_TYPE) \ - /* Note: the order of these external array */ \ - /* types is relied upon in */ \ - /* Object::IsExternalArray(). */ \ - V(EXTERNAL_BYTE_ARRAY_TYPE) \ - V(EXTERNAL_UNSIGNED_BYTE_ARRAY_TYPE) \ - V(EXTERNAL_SHORT_ARRAY_TYPE) \ - V(EXTERNAL_UNSIGNED_SHORT_ARRAY_TYPE) \ - V(EXTERNAL_INT_ARRAY_TYPE) \ - V(EXTERNAL_UNSIGNED_INT_ARRAY_TYPE) \ - V(EXTERNAL_FLOAT_ARRAY_TYPE) \ - V(EXTERNAL_PIXEL_ARRAY_TYPE) \ - V(FILLER_TYPE) \ - \ - V(DECLARED_ACCESSOR_DESCRIPTOR_TYPE) \ - V(DECLARED_ACCESSOR_INFO_TYPE) \ - V(EXECUTABLE_ACCESSOR_INFO_TYPE) \ - V(ACCESSOR_PAIR_TYPE) \ - V(ACCESS_CHECK_INFO_TYPE) \ - V(INTERCEPTOR_INFO_TYPE) \ - V(CALL_HANDLER_INFO_TYPE) \ - V(FUNCTION_TEMPLATE_INFO_TYPE) \ - V(OBJECT_TEMPLATE_INFO_TYPE) \ - V(SIGNATURE_INFO_TYPE) \ - V(TYPE_SWITCH_INFO_TYPE) \ - V(ALLOCATION_SITE_INFO_TYPE) \ - V(SCRIPT_TYPE) \ - V(CODE_CACHE_TYPE) \ - V(POLYMORPHIC_CODE_CACHE_TYPE) \ - V(TYPE_FEEDBACK_INFO_TYPE) \ - V(ALIASED_ARGUMENTS_ENTRY_TYPE) \ - \ - V(FIXED_ARRAY_TYPE) \ - V(FIXED_DOUBLE_ARRAY_TYPE) \ - V(SHARED_FUNCTION_INFO_TYPE) \ - \ - V(JS_MESSAGE_OBJECT_TYPE) \ - \ - V(JS_VALUE_TYPE) \ - V(JS_DATE_TYPE) \ - V(JS_OBJECT_TYPE) \ - V(JS_CONTEXT_EXTENSION_OBJECT_TYPE) \ - V(JS_MODULE_TYPE) \ - V(JS_GLOBAL_OBJECT_TYPE) \ - V(JS_BUILTINS_OBJECT_TYPE) \ - V(JS_GLOBAL_PROXY_TYPE) \ - V(JS_ARRAY_TYPE) \ - V(JS_PROXY_TYPE) \ - V(JS_WEAK_MAP_TYPE) \ - V(JS_REGEXP_TYPE) \ - \ - V(JS_FUNCTION_TYPE) \ - V(JS_FUNCTION_PROXY_TYPE) \ - -#ifdef ENABLE_DEBUGGER_SUPPORT -#define INSTANCE_TYPE_LIST_DEBUGGER(V) \ - V(DEBUG_INFO_TYPE) \ - V(BREAK_POINT_INFO_TYPE) -#else -#define INSTANCE_TYPE_LIST_DEBUGGER(V) -#endif - -#define INSTANCE_TYPE_LIST(V) \ - INSTANCE_TYPE_LIST_ALL(V) \ - INSTANCE_TYPE_LIST_DEBUGGER(V) - - -// Since string types are not consecutive, this macro is used to -// iterate over them. -#define STRING_TYPE_LIST(V) \ - V(STRING_TYPE, \ - kVariableSizeSentinel, \ - string, \ - String) \ - V(ASCII_STRING_TYPE, \ - kVariableSizeSentinel, \ - ascii_string, \ - AsciiString) \ - V(CONS_STRING_TYPE, \ - ConsString::kSize, \ - cons_string, \ - ConsString) \ - V(CONS_ASCII_STRING_TYPE, \ - ConsString::kSize, \ - cons_ascii_string, \ - ConsAsciiString) \ - V(SLICED_STRING_TYPE, \ - SlicedString::kSize, \ - sliced_string, \ - SlicedString) \ - V(SLICED_ASCII_STRING_TYPE, \ - SlicedString::kSize, \ - sliced_ascii_string, \ - SlicedAsciiString) \ - V(EXTERNAL_STRING_TYPE, \ - ExternalTwoByteString::kSize, \ - external_string, \ - ExternalString) \ - V(EXTERNAL_ASCII_STRING_TYPE, \ - ExternalAsciiString::kSize, \ - external_ascii_string, \ - ExternalAsciiString) \ - V(EXTERNAL_STRING_WITH_ASCII_DATA_TYPE, \ - ExternalTwoByteString::kSize, \ - external_string_with_ascii_data, \ - ExternalStringWithAsciiData) \ - V(SHORT_EXTERNAL_STRING_TYPE, \ - ExternalTwoByteString::kShortSize, \ - short_external_string, \ - ShortExternalString) \ - V(SHORT_EXTERNAL_ASCII_STRING_TYPE, \ - ExternalAsciiString::kShortSize, \ - short_external_ascii_string, \ - ShortExternalAsciiString) \ - V(SHORT_EXTERNAL_STRING_WITH_ASCII_DATA_TYPE, \ - ExternalTwoByteString::kShortSize, \ - short_external_string_with_ascii_data, \ - ShortExternalStringWithAsciiData) \ - \ - V(INTERNALIZED_STRING_TYPE, \ - kVariableSizeSentinel, \ - internalized_string, \ - InternalizedString) \ - V(ASCII_INTERNALIZED_STRING_TYPE, \ - kVariableSizeSentinel, \ - ascii_internalized_string, \ - AsciiInternalizedString) \ - V(CONS_INTERNALIZED_STRING_TYPE, \ - ConsString::kSize, \ - cons_internalized_string, \ - ConsInternalizedString) \ - V(CONS_ASCII_INTERNALIZED_STRING_TYPE, \ - ConsString::kSize, \ - cons_ascii_internalized_string, \ - ConsAsciiInternalizedString) \ - V(EXTERNAL_INTERNALIZED_STRING_TYPE, \ - ExternalTwoByteString::kSize, \ - external_internalized_string, \ - ExternalInternalizedString) \ - V(EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE, \ - ExternalAsciiString::kSize, \ - external_ascii_internalized_string, \ - ExternalAsciiInternalizedString) \ - V(EXTERNAL_INTERNALIZED_STRING_WITH_ASCII_DATA_TYPE, \ - ExternalTwoByteString::kSize, \ - external_internalized_string_with_ascii_data, \ - ExternalInternalizedStringWithAsciiData) \ - V(SHORT_EXTERNAL_INTERNALIZED_STRING_TYPE, \ - ExternalTwoByteString::kShortSize, \ - short_external_internalized_string, \ - ShortExternalInternalizedString) \ - V(SHORT_EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE, \ - ExternalAsciiString::kShortSize, \ - short_external_ascii_internalized_string, \ - ShortExternalAsciiInternalizedString) \ - V(SHORT_EXTERNAL_INTERNALIZED_STRING_WITH_ASCII_DATA_TYPE, \ - ExternalTwoByteString::kShortSize, \ - short_external_internalized_string_with_ascii_data, \ - ShortExternalInternalizedStringWithAsciiData) \ - -// A struct is a simple object a set of object-valued fields. Including an -// object type in this causes the compiler to generate most of the boilerplate -// code for the class including allocation and garbage collection routines, -// casts and predicates. All you need to define is the class, methods and -// object verification routines. Easy, no? -// -// Note that for subtle reasons related to the ordering or numerical values of -// type tags, elements in this list have to be added to the INSTANCE_TYPE_LIST -// manually. -#define STRUCT_LIST_ALL(V) \ - V(DECLARED_ACCESSOR_DESCRIPTOR, \ - DeclaredAccessorDescriptor, \ - declared_accessor_descriptor) \ - V(DECLARED_ACCESSOR_INFO, DeclaredAccessorInfo, declared_accessor_info) \ - V(EXECUTABLE_ACCESSOR_INFO, ExecutableAccessorInfo, executable_accessor_info)\ - V(ACCESSOR_PAIR, AccessorPair, accessor_pair) \ - V(ACCESS_CHECK_INFO, AccessCheckInfo, access_check_info) \ - V(INTERCEPTOR_INFO, InterceptorInfo, interceptor_info) \ - V(CALL_HANDLER_INFO, CallHandlerInfo, call_handler_info) \ - V(FUNCTION_TEMPLATE_INFO, FunctionTemplateInfo, function_template_info) \ - V(OBJECT_TEMPLATE_INFO, ObjectTemplateInfo, object_template_info) \ - V(SIGNATURE_INFO, SignatureInfo, signature_info) \ - V(TYPE_SWITCH_INFO, TypeSwitchInfo, type_switch_info) \ - V(SCRIPT, Script, script) \ - V(ALLOCATION_SITE_INFO, AllocationSiteInfo, allocation_site_info) \ - V(CODE_CACHE, CodeCache, code_cache) \ - V(POLYMORPHIC_CODE_CACHE, PolymorphicCodeCache, polymorphic_code_cache) \ - V(TYPE_FEEDBACK_INFO, TypeFeedbackInfo, type_feedback_info) \ - V(ALIASED_ARGUMENTS_ENTRY, AliasedArgumentsEntry, aliased_arguments_entry) - -#ifdef ENABLE_DEBUGGER_SUPPORT -#define STRUCT_LIST_DEBUGGER(V) \ - V(DEBUG_INFO, DebugInfo, debug_info) \ - V(BREAK_POINT_INFO, BreakPointInfo, break_point_info) -#else -#define STRUCT_LIST_DEBUGGER(V) -#endif - -#define STRUCT_LIST(V) \ - STRUCT_LIST_ALL(V) \ - STRUCT_LIST_DEBUGGER(V) - -// We use the full 8 bits of the instance_type field to encode heap object -// instance types. The high-order bit (bit 7) is set if the object is not a -// string, and cleared if it is a string. -const uint32_t kIsNotStringMask = 0x80; -const uint32_t kStringTag = 0x0; -const uint32_t kNotStringTag = 0x80; - -// Bit 6 indicates that the object is an internalized string (if set) or not. -// There are not enough types that the non-string types (with bit 7 set) can -// have bit 6 set too. -const uint32_t kIsInternalizedMask = 0x40; -const uint32_t kNotInternalizedTag = 0x0; -const uint32_t kInternalizedTag = 0x40; - -// If bit 7 is clear then bit 2 indicates whether the string consists of -// two-byte characters or one-byte characters. -const uint32_t kStringEncodingMask = 0x4; -const uint32_t kTwoByteStringTag = 0x0; -const uint32_t kOneByteStringTag = 0x4; - -// If bit 7 is clear, the low-order 2 bits indicate the representation -// of the string. -const uint32_t kStringRepresentationMask = 0x03; -enum StringRepresentationTag { - kSeqStringTag = 0x0, - kConsStringTag = 0x1, - kExternalStringTag = 0x2, - kSlicedStringTag = 0x3 -}; -const uint32_t kIsIndirectStringMask = 0x1; -const uint32_t kIsIndirectStringTag = 0x1; -STATIC_ASSERT((kSeqStringTag & kIsIndirectStringMask) == 0); -STATIC_ASSERT((kExternalStringTag & kIsIndirectStringMask) == 0); -STATIC_ASSERT( - (kConsStringTag & kIsIndirectStringMask) == kIsIndirectStringTag); -STATIC_ASSERT( - (kSlicedStringTag & kIsIndirectStringMask) == kIsIndirectStringTag); - -// Use this mask to distinguish between cons and slice only after making -// sure that the string is one of the two (an indirect string). -const uint32_t kSlicedNotConsMask = kSlicedStringTag & ~kConsStringTag; -STATIC_ASSERT(IS_POWER_OF_TWO(kSlicedNotConsMask) && kSlicedNotConsMask != 0); - -// If bit 7 is clear, then bit 3 indicates whether this two-byte -// string actually contains ASCII data. -const uint32_t kAsciiDataHintMask = 0x08; -const uint32_t kAsciiDataHintTag = 0x08; - -// If bit 7 is clear and string representation indicates an external string, -// then bit 4 indicates whether the data pointer is cached. -const uint32_t kShortExternalStringMask = 0x10; -const uint32_t kShortExternalStringTag = 0x10; - - -// A ConsString with an empty string as the right side is a candidate -// for being shortcut by the garbage collector unless it is internalized. -// It's not common to have non-flat internalized strings, so we do not -// shortcut them thereby avoiding turning internalized strings into strings. -// See heap.cc and mark-compact.cc. -const uint32_t kShortcutTypeMask = - kIsNotStringMask | - kIsInternalizedMask | - kStringRepresentationMask; -const uint32_t kShortcutTypeTag = kConsStringTag; - - -enum InstanceType { - // String types. - STRING_TYPE = kTwoByteStringTag | kSeqStringTag, - ASCII_STRING_TYPE = kOneByteStringTag | kSeqStringTag, - CONS_STRING_TYPE = kTwoByteStringTag | kConsStringTag, - CONS_ASCII_STRING_TYPE = kOneByteStringTag | kConsStringTag, - SLICED_STRING_TYPE = kTwoByteStringTag | kSlicedStringTag, - SLICED_ASCII_STRING_TYPE = kOneByteStringTag | kSlicedStringTag, - EXTERNAL_STRING_TYPE = kTwoByteStringTag | kExternalStringTag, - EXTERNAL_ASCII_STRING_TYPE = kOneByteStringTag | kExternalStringTag, - EXTERNAL_STRING_WITH_ASCII_DATA_TYPE = - EXTERNAL_STRING_TYPE | kAsciiDataHintTag, - SHORT_EXTERNAL_STRING_TYPE = EXTERNAL_STRING_TYPE | kShortExternalStringTag, - SHORT_EXTERNAL_ASCII_STRING_TYPE = - EXTERNAL_ASCII_STRING_TYPE | kShortExternalStringTag, - SHORT_EXTERNAL_STRING_WITH_ASCII_DATA_TYPE = - EXTERNAL_STRING_WITH_ASCII_DATA_TYPE | kShortExternalStringTag, - - INTERNALIZED_STRING_TYPE = STRING_TYPE | kInternalizedTag, - ASCII_INTERNALIZED_STRING_TYPE = ASCII_STRING_TYPE | kInternalizedTag, - CONS_INTERNALIZED_STRING_TYPE = CONS_STRING_TYPE | kInternalizedTag, - CONS_ASCII_INTERNALIZED_STRING_TYPE = - CONS_ASCII_STRING_TYPE | kInternalizedTag, - EXTERNAL_INTERNALIZED_STRING_TYPE = EXTERNAL_STRING_TYPE | kInternalizedTag, - EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE = - EXTERNAL_ASCII_STRING_TYPE | kInternalizedTag, - EXTERNAL_INTERNALIZED_STRING_WITH_ASCII_DATA_TYPE = - EXTERNAL_STRING_WITH_ASCII_DATA_TYPE | kInternalizedTag, - SHORT_EXTERNAL_INTERNALIZED_STRING_TYPE = - SHORT_EXTERNAL_STRING_TYPE | kInternalizedTag, - SHORT_EXTERNAL_ASCII_INTERNALIZED_STRING_TYPE = - SHORT_EXTERNAL_ASCII_STRING_TYPE | kInternalizedTag, - SHORT_EXTERNAL_INTERNALIZED_STRING_WITH_ASCII_DATA_TYPE = - SHORT_EXTERNAL_STRING_WITH_ASCII_DATA_TYPE | kInternalizedTag, - - // Non-string names - SYMBOL_TYPE = kNotStringTag, // LAST_NAME_TYPE, FIRST_NONSTRING_TYPE - - // Objects allocated in their own spaces (never in new space). - MAP_TYPE, - CODE_TYPE, - ODDBALL_TYPE, - JS_GLOBAL_PROPERTY_CELL_TYPE, - - // "Data", objects that cannot contain non-map-word pointers to heap - // objects. - HEAP_NUMBER_TYPE, - FOREIGN_TYPE, - BYTE_ARRAY_TYPE, - FREE_SPACE_TYPE, - EXTERNAL_BYTE_ARRAY_TYPE, // FIRST_EXTERNAL_ARRAY_TYPE - EXTERNAL_UNSIGNED_BYTE_ARRAY_TYPE, - EXTERNAL_SHORT_ARRAY_TYPE, - EXTERNAL_UNSIGNED_SHORT_ARRAY_TYPE, - EXTERNAL_INT_ARRAY_TYPE, - EXTERNAL_UNSIGNED_INT_ARRAY_TYPE, - EXTERNAL_FLOAT_ARRAY_TYPE, - EXTERNAL_DOUBLE_ARRAY_TYPE, - EXTERNAL_PIXEL_ARRAY_TYPE, // LAST_EXTERNAL_ARRAY_TYPE - FIXED_DOUBLE_ARRAY_TYPE, - FILLER_TYPE, // LAST_DATA_TYPE - - // Structs. - DECLARED_ACCESSOR_DESCRIPTOR_TYPE, - DECLARED_ACCESSOR_INFO_TYPE, - EXECUTABLE_ACCESSOR_INFO_TYPE, - ACCESSOR_PAIR_TYPE, - ACCESS_CHECK_INFO_TYPE, - INTERCEPTOR_INFO_TYPE, - CALL_HANDLER_INFO_TYPE, - FUNCTION_TEMPLATE_INFO_TYPE, - OBJECT_TEMPLATE_INFO_TYPE, - SIGNATURE_INFO_TYPE, - TYPE_SWITCH_INFO_TYPE, - ALLOCATION_SITE_INFO_TYPE, - SCRIPT_TYPE, - CODE_CACHE_TYPE, - POLYMORPHIC_CODE_CACHE_TYPE, - TYPE_FEEDBACK_INFO_TYPE, - ALIASED_ARGUMENTS_ENTRY_TYPE, - // The following two instance types are only used when ENABLE_DEBUGGER_SUPPORT - // is defined. However as include/v8.h contain some of the instance type - // constants always having them avoids them getting different numbers - // depending on whether ENABLE_DEBUGGER_SUPPORT is defined or not. - DEBUG_INFO_TYPE, - BREAK_POINT_INFO_TYPE, - - FIXED_ARRAY_TYPE, - SHARED_FUNCTION_INFO_TYPE, - - JS_MESSAGE_OBJECT_TYPE, - - // All the following types are subtypes of JSReceiver, which corresponds to - // objects in the JS sense. The first and the last type in this range are - // the two forms of function. This organization enables using the same - // compares for checking the JS_RECEIVER/SPEC_OBJECT range and the - // NONCALLABLE_JS_OBJECT range. - JS_FUNCTION_PROXY_TYPE, // FIRST_JS_RECEIVER_TYPE, FIRST_JS_PROXY_TYPE - JS_PROXY_TYPE, // LAST_JS_PROXY_TYPE - - JS_VALUE_TYPE, // FIRST_JS_OBJECT_TYPE - JS_DATE_TYPE, - JS_OBJECT_TYPE, - JS_CONTEXT_EXTENSION_OBJECT_TYPE, - JS_MODULE_TYPE, - JS_GLOBAL_OBJECT_TYPE, - JS_BUILTINS_OBJECT_TYPE, - JS_GLOBAL_PROXY_TYPE, - JS_ARRAY_TYPE, - JS_SET_TYPE, - JS_MAP_TYPE, - JS_WEAK_MAP_TYPE, - - JS_REGEXP_TYPE, - - JS_FUNCTION_TYPE, // LAST_JS_OBJECT_TYPE, LAST_JS_RECEIVER_TYPE - - // Pseudo-types - FIRST_TYPE = 0x0, - LAST_TYPE = JS_FUNCTION_TYPE, - INVALID_TYPE = FIRST_TYPE - 1, - FIRST_NAME_TYPE = FIRST_TYPE, - LAST_NAME_TYPE = SYMBOL_TYPE, - FIRST_UNIQUE_NAME_TYPE = INTERNALIZED_STRING_TYPE, - LAST_UNIQUE_NAME_TYPE = SYMBOL_TYPE, - FIRST_NONSTRING_TYPE = SYMBOL_TYPE, - // Boundaries for testing for an external array. - FIRST_EXTERNAL_ARRAY_TYPE = EXTERNAL_BYTE_ARRAY_TYPE, - LAST_EXTERNAL_ARRAY_TYPE = EXTERNAL_PIXEL_ARRAY_TYPE, - // Boundary for promotion to old data space/old pointer space. - LAST_DATA_TYPE = FILLER_TYPE, - // Boundary for objects represented as JSReceiver (i.e. JSObject or JSProxy). - // Note that there is no range for JSObject or JSProxy, since their subtypes - // are not continuous in this enum! The enum ranges instead reflect the - // external class names, where proxies are treated as either ordinary objects, - // or functions. - FIRST_JS_RECEIVER_TYPE = JS_FUNCTION_PROXY_TYPE, - LAST_JS_RECEIVER_TYPE = LAST_TYPE, - // Boundaries for testing the types represented as JSObject - FIRST_JS_OBJECT_TYPE = JS_VALUE_TYPE, - LAST_JS_OBJECT_TYPE = LAST_TYPE, - // Boundaries for testing the types represented as JSProxy - FIRST_JS_PROXY_TYPE = JS_FUNCTION_PROXY_TYPE, - LAST_JS_PROXY_TYPE = JS_PROXY_TYPE, - // Boundaries for testing whether the type is a JavaScript object. - FIRST_SPEC_OBJECT_TYPE = FIRST_JS_RECEIVER_TYPE, - LAST_SPEC_OBJECT_TYPE = LAST_JS_RECEIVER_TYPE, - // Boundaries for testing the types for which typeof is "object". - FIRST_NONCALLABLE_SPEC_OBJECT_TYPE = JS_PROXY_TYPE, - LAST_NONCALLABLE_SPEC_OBJECT_TYPE = JS_REGEXP_TYPE, - // Note that the types for which typeof is "function" are not continuous. - // Define this so that we can put assertions on discrete checks. - NUM_OF_CALLABLE_SPEC_OBJECT_TYPES = 2 -}; - -const int kExternalArrayTypeCount = - LAST_EXTERNAL_ARRAY_TYPE - FIRST_EXTERNAL_ARRAY_TYPE + 1; - -STATIC_CHECK(JS_OBJECT_TYPE == Internals::kJSObjectType); -STATIC_CHECK(FIRST_NONSTRING_TYPE == Internals::kFirstNonstringType); -STATIC_CHECK(ODDBALL_TYPE == Internals::kOddballType); -STATIC_CHECK(FOREIGN_TYPE == Internals::kForeignType); - - -#define FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(V) \ - V(FAST_ELEMENTS_SUB_TYPE) \ - V(DICTIONARY_ELEMENTS_SUB_TYPE) \ - V(FAST_PROPERTIES_SUB_TYPE) \ - V(DICTIONARY_PROPERTIES_SUB_TYPE) \ - V(MAP_CODE_CACHE_SUB_TYPE) \ - V(SCOPE_INFO_SUB_TYPE) \ - V(STRING_TABLE_SUB_TYPE) \ - V(DESCRIPTOR_ARRAY_SUB_TYPE) \ - V(TRANSITION_ARRAY_SUB_TYPE) - -enum FixedArraySubInstanceType { -#define DEFINE_FIXED_ARRAY_SUB_INSTANCE_TYPE(name) name, - FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(DEFINE_FIXED_ARRAY_SUB_INSTANCE_TYPE) -#undef DEFINE_FIXED_ARRAY_SUB_INSTANCE_TYPE - LAST_FIXED_ARRAY_SUB_TYPE = TRANSITION_ARRAY_SUB_TYPE -}; - - -enum CompareResult { - LESS = -1, - EQUAL = 0, - GREATER = 1, - - NOT_EQUAL = GREATER -}; - - -#define DECL_BOOLEAN_ACCESSORS(name) \ - inline bool name(); \ - inline void set_##name(bool value); \ - - -#define DECL_ACCESSORS(name, type) \ - inline type* name(); \ - inline void set_##name(type* value, \ - WriteBarrierMode mode = UPDATE_WRITE_BARRIER); \ - - -class AccessorPair; -class DictionaryElementsAccessor; -class ElementsAccessor; -class Failure; -class FixedArrayBase; -class ObjectVisitor; -class StringStream; - -struct ValueInfo : public Malloced { - ValueInfo() : type(FIRST_TYPE), ptr(NULL), str(NULL), number(0) { } - InstanceType type; - Object* ptr; - const char* str; - double number; -}; - - -// A template-ized version of the IsXXX functions. -template <class C> static inline bool Is(Object* obj); - -#ifdef VERIFY_HEAP -#define DECLARE_VERIFIER(Name) void Name##Verify(); -#else -#define DECLARE_VERIFIER(Name) -#endif - -#ifdef OBJECT_PRINT -#define DECLARE_PRINTER(Name) void Name##Print(FILE* out = stdout); -#else -#define DECLARE_PRINTER(Name) -#endif - -class MaybeObject BASE_EMBEDDED { - public: - inline bool IsFailure(); - inline bool IsRetryAfterGC(); - inline bool IsOutOfMemory(); - inline bool IsException(); - INLINE(bool IsTheHole()); - inline bool ToObject(Object** obj) { - if (IsFailure()) return false; - *obj = reinterpret_cast<Object*>(this); - return true; - } - inline Failure* ToFailureUnchecked() { - ASSERT(IsFailure()); - return reinterpret_cast<Failure*>(this); - } - inline Object* ToObjectUnchecked() { - // TODO(jkummerow): Turn this back into an ASSERT when we can be certain - // that it never fires in Release mode in the wild. - CHECK(!IsFailure()); - return reinterpret_cast<Object*>(this); - } - inline Object* ToObjectChecked() { - CHECK(!IsFailure()); - return reinterpret_cast<Object*>(this); - } - - template<typename T> - inline bool To(T** obj) { - if (IsFailure()) return false; - *obj = T::cast(reinterpret_cast<Object*>(this)); - return true; - } - - template<typename T> - inline bool ToHandle(Handle<T>* obj, Isolate* isolate) { - if (IsFailure()) return false; - *obj = handle(T::cast(reinterpret_cast<Object*>(this)), isolate); - return true; - } - -#ifdef OBJECT_PRINT - // Prints this object with details. - inline void Print() { - Print(stdout); - } - inline void PrintLn() { - PrintLn(stdout); - } - void Print(FILE* out); - void PrintLn(FILE* out); -#endif -#ifdef VERIFY_HEAP - // Verifies the object. - void Verify(); -#endif -}; - - -#define OBJECT_TYPE_LIST(V) \ - V(Smi) \ - V(HeapObject) \ - V(Number) \ - -#define HEAP_OBJECT_TYPE_LIST(V) \ - V(HeapNumber) \ - V(Name) \ - V(UniqueName) \ - V(String) \ - V(SeqString) \ - V(ExternalString) \ - V(ConsString) \ - V(SlicedString) \ - V(ExternalTwoByteString) \ - V(ExternalAsciiString) \ - V(SeqTwoByteString) \ - V(SeqOneByteString) \ - V(InternalizedString) \ - V(Symbol) \ - \ - V(ExternalArray) \ - V(ExternalByteArray) \ - V(ExternalUnsignedByteArray) \ - V(ExternalShortArray) \ - V(ExternalUnsignedShortArray) \ - V(ExternalIntArray) \ - V(ExternalUnsignedIntArray) \ - V(ExternalFloatArray) \ - V(ExternalDoubleArray) \ - V(ExternalPixelArray) \ - V(ByteArray) \ - V(FreeSpace) \ - V(JSReceiver) \ - V(JSObject) \ - V(JSContextExtensionObject) \ - V(JSModule) \ - V(Map) \ - V(DescriptorArray) \ - V(TransitionArray) \ - V(DeoptimizationInputData) \ - V(DeoptimizationOutputData) \ - V(DependentCode) \ - V(TypeFeedbackCells) \ - V(FixedArray) \ - V(FixedDoubleArray) \ - V(Context) \ - V(NativeContext) \ - V(ScopeInfo) \ - V(JSFunction) \ - V(Code) \ - V(Oddball) \ - V(SharedFunctionInfo) \ - V(JSValue) \ - V(JSDate) \ - V(JSMessageObject) \ - V(StringWrapper) \ - V(Foreign) \ - V(Boolean) \ - V(JSArray) \ - V(JSProxy) \ - V(JSFunctionProxy) \ - V(JSSet) \ - V(JSMap) \ - V(JSWeakMap) \ - V(JSRegExp) \ - V(HashTable) \ - V(Dictionary) \ - V(StringTable) \ - V(JSFunctionResultCache) \ - V(NormalizedMapCache) \ - V(CompilationCacheTable) \ - V(CodeCacheHashTable) \ - V(PolymorphicCodeCacheHashTable) \ - V(MapCache) \ - V(Primitive) \ - V(GlobalObject) \ - V(JSGlobalObject) \ - V(JSBuiltinsObject) \ - V(JSGlobalProxy) \ - V(UndetectableObject) \ - V(AccessCheckNeeded) \ - V(JSGlobalPropertyCell) \ - V(ObjectHashTable) \ - - -class JSReceiver; - -// Object is the abstract superclass for all classes in the -// object hierarchy. -// Object does not use any virtual functions to avoid the -// allocation of the C++ vtable. -// Since Smi and Failure are subclasses of Object no -// data members can be present in Object. -class Object : public MaybeObject { - public: - // Type testing. - bool IsObject() { return true; } - -#define IS_TYPE_FUNCTION_DECL(type_) inline bool Is##type_(); - OBJECT_TYPE_LIST(IS_TYPE_FUNCTION_DECL) - HEAP_OBJECT_TYPE_LIST(IS_TYPE_FUNCTION_DECL) -#undef IS_TYPE_FUNCTION_DECL - - inline bool IsFixedArrayBase(); - inline bool IsExternal(); - inline bool IsAccessorInfo(); - - // Returns true if this object is an instance of the specified - // function template. - inline bool IsInstanceOf(FunctionTemplateInfo* type); - - inline bool IsStruct(); -#define DECLARE_STRUCT_PREDICATE(NAME, Name, name) inline bool Is##Name(); - STRUCT_LIST(DECLARE_STRUCT_PREDICATE) -#undef DECLARE_STRUCT_PREDICATE - - INLINE(bool IsSpecObject()); - INLINE(bool IsSpecFunction()); - - // Oddball testing. - INLINE(bool IsUndefined()); - INLINE(bool IsNull()); - INLINE(bool IsTheHole()); // Shadows MaybeObject's implementation. - INLINE(bool IsTrue()); - INLINE(bool IsFalse()); - inline bool IsArgumentsMarker(); - inline bool NonFailureIsHeapObject(); - - // Filler objects (fillers and free space objects). - inline bool IsFiller(); - - // Extract the number. - inline double Number(); - inline bool IsNaN(); - - // Returns true if the object is of the correct type to be used as a - // implementation of a JSObject's elements. - inline bool HasValidElements(); - - inline bool HasSpecificClassOf(String* name); - - MUST_USE_RESULT MaybeObject* ToObject(); // ECMA-262 9.9. - Object* ToBoolean(); // ECMA-262 9.2. - - // Convert to a JSObject if needed. - // native_context is used when creating wrapper object. - MUST_USE_RESULT MaybeObject* ToObject(Context* native_context); - - // Converts this to a Smi if possible. - // Failure is returned otherwise. - MUST_USE_RESULT inline MaybeObject* ToSmi(); - - void Lookup(String* name, LookupResult* result); - - // Property access. - MUST_USE_RESULT inline MaybeObject* GetProperty(String* key); - MUST_USE_RESULT inline MaybeObject* GetProperty( - String* key, - PropertyAttributes* attributes); - MUST_USE_RESULT MaybeObject* GetPropertyWithReceiver( - Object* receiver, - String* key, - PropertyAttributes* attributes); - - static Handle<Object> GetProperty(Handle<Object> object, Handle<String> key); - static Handle<Object> GetProperty(Handle<Object> object, - Handle<Object> receiver, - LookupResult* result, - Handle<String> key, - PropertyAttributes* attributes); - - MUST_USE_RESULT MaybeObject* GetProperty(Object* receiver, - LookupResult* result, - String* key, - PropertyAttributes* attributes); - - MUST_USE_RESULT MaybeObject* GetPropertyWithDefinedGetter(Object* receiver, - JSReceiver* getter); - - static Handle<Object> GetElement(Handle<Object> object, uint32_t index); - MUST_USE_RESULT inline MaybeObject* GetElement(uint32_t index); - // For use when we know that no exception can be thrown. - inline Object* GetElementNoExceptionThrown(uint32_t index); - MUST_USE_RESULT MaybeObject* GetElementWithReceiver(Object* receiver, - uint32_t index); - - // Return the object's prototype (might be Heap::null_value()). - Object* GetPrototype(Isolate* isolate); - - // Return the prototype, or the method holder for a value-like object. - Object* GetDelegate(Isolate* isolate); - - // Returns the permanent hash code associated with this object depending on - // the actual object type. Might return a failure in case no hash was - // created yet or GC was caused by creation. - MUST_USE_RESULT MaybeObject* GetHash(CreationFlag flag); - - // Checks whether this object has the same value as the given one. This - // function is implemented according to ES5, section 9.12 and can be used - // to implement the Harmony "egal" function. - bool SameValue(Object* other); - - // Tries to convert an object to an array index. Returns true and sets - // the output parameter if it succeeds. - inline bool ToArrayIndex(uint32_t* index); - - // Returns true if this is a JSValue containing a string and the index is - // < the length of the string. Used to implement [] on strings. - inline bool IsStringObjectWithCharacterAt(uint32_t index); - -#ifdef VERIFY_HEAP - // Verify a pointer is a valid object pointer. - static void VerifyPointer(Object* p); -#endif - - inline void VerifyApiCallResultType(); - - // Prints this object without details. - inline void ShortPrint() { - ShortPrint(stdout); - } - void ShortPrint(FILE* out); - - // Prints this object without details to a message accumulator. - void ShortPrint(StringStream* accumulator); - - // Casting: This cast is only needed to satisfy macros in objects-inl.h. - static Object* cast(Object* value) { return value; } - - // Layout description. - static const int kHeaderSize = 0; // Object does not take up any space. - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(Object); -}; - - -// Smi represents integer Numbers that can be stored in 31 bits. -// Smis are immediate which means they are NOT allocated in the heap. -// The this pointer has the following format: [31 bit signed int] 0 -// For long smis it has the following format: -// [32 bit signed int] [31 bits zero padding] 0 -// Smi stands for small integer. -class Smi: public Object { - public: - // Returns the integer value. - inline int value(); - - // Convert a value to a Smi object. - static inline Smi* FromInt(int value); - - static inline Smi* FromIntptr(intptr_t value); - - // Returns whether value can be represented in a Smi. - static inline bool IsValid(intptr_t value); - - // Casting. - static inline Smi* cast(Object* object); - - // Dispatched behavior. - inline void SmiPrint() { - SmiPrint(stdout); - } - void SmiPrint(FILE* out); - void SmiPrint(StringStream* accumulator); - - DECLARE_VERIFIER(Smi) - - static const int kMinValue = - (static_cast<unsigned int>(-1)) << (kSmiValueSize - 1); - static const int kMaxValue = -(kMinValue + 1); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(Smi); -}; - - -// Failure is used for reporting out of memory situations and -// propagating exceptions through the runtime system. Failure objects -// are transient and cannot occur as part of the object graph. -// -// Failures are a single word, encoded as follows: -// +-------------------------+---+--+--+ -// |.........unused..........|sss|tt|11| -// +-------------------------+---+--+--+ -// 7 6 4 32 10 -// -// -// The low two bits, 0-1, are the failure tag, 11. The next two bits, -// 2-3, are a failure type tag 'tt' with possible values: -// 00 RETRY_AFTER_GC -// 01 EXCEPTION -// 10 INTERNAL_ERROR -// 11 OUT_OF_MEMORY_EXCEPTION -// -// The next three bits, 4-6, are an allocation space tag 'sss'. The -// allocation space tag is 000 for all failure types except -// RETRY_AFTER_GC. For RETRY_AFTER_GC, the possible values are the -// allocation spaces (the encoding is found in globals.h). - -// Failure type tag info. -const int kFailureTypeTagSize = 2; -const int kFailureTypeTagMask = (1 << kFailureTypeTagSize) - 1; - -class Failure: public MaybeObject { - public: - // RuntimeStubs assumes EXCEPTION = 1 in the compiler-generated code. - enum Type { - RETRY_AFTER_GC = 0, - EXCEPTION = 1, // Returning this marker tells the real exception - // is in Isolate::pending_exception. - INTERNAL_ERROR = 2, - OUT_OF_MEMORY_EXCEPTION = 3 - }; - - inline Type type() const; - - // Returns the space that needs to be collected for RetryAfterGC failures. - inline AllocationSpace allocation_space() const; - - inline bool IsInternalError() const; - inline bool IsOutOfMemoryException() const; - - static inline Failure* RetryAfterGC(AllocationSpace space); - static inline Failure* RetryAfterGC(); // NEW_SPACE - static inline Failure* Exception(); - static inline Failure* InternalError(); - // TODO(jkummerow): The value is temporary instrumentation. Remove it - // when it has served its purpose. - static inline Failure* OutOfMemoryException(intptr_t value); - // Casting. - static inline Failure* cast(MaybeObject* object); - - // Dispatched behavior. - inline void FailurePrint() { - FailurePrint(stdout); - } - void FailurePrint(FILE* out); - void FailurePrint(StringStream* accumulator); - - DECLARE_VERIFIER(Failure) - - private: - inline intptr_t value() const; - static inline Failure* Construct(Type type, intptr_t value = 0); - - DISALLOW_IMPLICIT_CONSTRUCTORS(Failure); -}; - - -// Heap objects typically have a map pointer in their first word. However, -// during GC other data (e.g. mark bits, forwarding addresses) is sometimes -// encoded in the first word. The class MapWord is an abstraction of the -// value in a heap object's first word. -class MapWord BASE_EMBEDDED { - public: - // Normal state: the map word contains a map pointer. - - // Create a map word from a map pointer. - static inline MapWord FromMap(Map* map); - - // View this map word as a map pointer. - inline Map* ToMap(); - - - // Scavenge collection: the map word of live objects in the from space - // contains a forwarding address (a heap object pointer in the to space). - - // True if this map word is a forwarding address for a scavenge - // collection. Only valid during a scavenge collection (specifically, - // when all map words are heap object pointers, i.e. not during a full GC). - inline bool IsForwardingAddress(); - - // Create a map word from a forwarding address. - static inline MapWord FromForwardingAddress(HeapObject* object); - - // View this map word as a forwarding address. - inline HeapObject* ToForwardingAddress(); - - static inline MapWord FromRawValue(uintptr_t value) { - return MapWord(value); - } - - inline uintptr_t ToRawValue() { - return value_; - } - - private: - // HeapObject calls the private constructor and directly reads the value. - friend class HeapObject; - - explicit MapWord(uintptr_t value) : value_(value) {} - - uintptr_t value_; -}; - - -// HeapObject is the superclass for all classes describing heap allocated -// objects. -class HeapObject: public Object { - public: - // [map]: Contains a map which contains the object's reflective - // information. - inline Map* map(); - inline void set_map(Map* value); - // The no-write-barrier version. This is OK if the object is white and in - // new space, or if the value is an immortal immutable object, like the maps - // of primitive (non-JS) objects like strings, heap numbers etc. - inline void set_map_no_write_barrier(Map* value); - - // During garbage collection, the map word of a heap object does not - // necessarily contain a map pointer. - inline MapWord map_word(); - inline void set_map_word(MapWord map_word); - - // The Heap the object was allocated in. Used also to access Isolate. - inline Heap* GetHeap(); - - // Convenience method to get current isolate. This method can be - // accessed only when its result is the same as - // Isolate::Current(), it ASSERTs this. See also comment for GetHeap. - inline Isolate* GetIsolate(); - - // Converts an address to a HeapObject pointer. - static inline HeapObject* FromAddress(Address address); - - // Returns the address of this HeapObject. - inline Address address(); - - // Iterates over pointers contained in the object (including the Map) - void Iterate(ObjectVisitor* v); - - // Iterates over all pointers contained in the object except the - // first map pointer. The object type is given in the first - // parameter. This function does not access the map pointer in the - // object, and so is safe to call while the map pointer is modified. - void IterateBody(InstanceType type, int object_size, ObjectVisitor* v); - - // Returns the heap object's size in bytes - inline int Size(); - - // Given a heap object's map pointer, returns the heap size in bytes - // Useful when the map pointer field is used for other purposes. - // GC internal. - inline int SizeFromMap(Map* map); - - // Returns the field at offset in obj, as a read/write Object* reference. - // Does no checking, and is safe to use during GC, while maps are invalid. - // Does not invoke write barrier, so should only be assigned to - // during marking GC. - static inline Object** RawField(HeapObject* obj, int offset); - - // Casting. - static inline HeapObject* cast(Object* obj); - - // Return the write barrier mode for this. Callers of this function - // must be able to present a reference to an AssertNoAllocation - // object as a sign that they are not going to use this function - // from code that allocates and thus invalidates the returned write - // barrier mode. - inline WriteBarrierMode GetWriteBarrierMode(const AssertNoAllocation&); - - // Dispatched behavior. - void HeapObjectShortPrint(StringStream* accumulator); -#ifdef OBJECT_PRINT - inline void HeapObjectPrint() { - HeapObjectPrint(stdout); - } - void HeapObjectPrint(FILE* out); - void PrintHeader(FILE* out, const char* id); -#endif - DECLARE_VERIFIER(HeapObject) -#ifdef VERIFY_HEAP - inline void VerifyObjectField(int offset); - inline void VerifySmiField(int offset); - - // Verify a pointer is a valid HeapObject pointer that points to object - // areas in the heap. - static void VerifyHeapPointer(Object* p); -#endif - - // Layout description. - // First field in a heap object is map. - static const int kMapOffset = Object::kHeaderSize; - static const int kHeaderSize = kMapOffset + kPointerSize; - - STATIC_CHECK(kMapOffset == Internals::kHeapObjectMapOffset); - - protected: - // helpers for calling an ObjectVisitor to iterate over pointers in the - // half-open range [start, end) specified as integer offsets - inline void IteratePointers(ObjectVisitor* v, int start, int end); - // as above, for the single element at "offset" - inline void IteratePointer(ObjectVisitor* v, int offset); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(HeapObject); -}; - - -// This class describes a body of an object of a fixed size -// in which all pointer fields are located in the [start_offset, end_offset) -// interval. -template<int start_offset, int end_offset, int size> -class FixedBodyDescriptor { - public: - static const int kStartOffset = start_offset; - static const int kEndOffset = end_offset; - static const int kSize = size; - - static inline void IterateBody(HeapObject* obj, ObjectVisitor* v); - - template<typename StaticVisitor> - static inline void IterateBody(HeapObject* obj) { - StaticVisitor::VisitPointers(HeapObject::RawField(obj, start_offset), - HeapObject::RawField(obj, end_offset)); - } -}; - - -// This class describes a body of an object of a variable size -// in which all pointer fields are located in the [start_offset, object_size) -// interval. -template<int start_offset> -class FlexibleBodyDescriptor { - public: - static const int kStartOffset = start_offset; - - static inline void IterateBody(HeapObject* obj, - int object_size, - ObjectVisitor* v); - - template<typename StaticVisitor> - static inline void IterateBody(HeapObject* obj, int object_size) { - StaticVisitor::VisitPointers(HeapObject::RawField(obj, start_offset), - HeapObject::RawField(obj, object_size)); - } -}; - - -// The HeapNumber class describes heap allocated numbers that cannot be -// represented in a Smi (small integer) -class HeapNumber: public HeapObject { - public: - // [value]: number value. - inline double value(); - inline void set_value(double value); - - // Casting. - static inline HeapNumber* cast(Object* obj); - - // Dispatched behavior. - Object* HeapNumberToBoolean(); - inline void HeapNumberPrint() { - HeapNumberPrint(stdout); - } - void HeapNumberPrint(FILE* out); - void HeapNumberPrint(StringStream* accumulator); - DECLARE_VERIFIER(HeapNumber) - - inline int get_exponent(); - inline int get_sign(); - - // Layout description. - static const int kValueOffset = HeapObject::kHeaderSize; - // IEEE doubles are two 32 bit words. The first is just mantissa, the second - // is a mixture of sign, exponent and mantissa. Our current platforms are all - // little endian apart from non-EABI arm which is little endian with big - // endian floating point word ordering! - static const int kMantissaOffset = kValueOffset; - static const int kExponentOffset = kValueOffset + 4; - - static const int kSize = kValueOffset + kDoubleSize; - static const uint32_t kSignMask = 0x80000000u; - static const uint32_t kExponentMask = 0x7ff00000u; - static const uint32_t kMantissaMask = 0xfffffu; - static const int kMantissaBits = 52; - static const int kExponentBits = 11; - static const int kExponentBias = 1023; - static const int kExponentShift = 20; - static const int kMantissaBitsInTopWord = 20; - static const int kNonMantissaBitsInTopWord = 12; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(HeapNumber); -}; - - -enum EnsureElementsMode { - DONT_ALLOW_DOUBLE_ELEMENTS, - ALLOW_COPIED_DOUBLE_ELEMENTS, - ALLOW_CONVERTED_DOUBLE_ELEMENTS -}; - - -// Indicates whether a property should be set or (re)defined. Setting of a -// property causes attributes to remain unchanged, writability to be checked -// and callbacks to be called. Defining of a property causes attributes to -// be updated and callbacks to be overridden. -enum SetPropertyMode { - SET_PROPERTY, - DEFINE_PROPERTY -}; - - -// Indicator for one component of an AccessorPair. -enum AccessorComponent { - ACCESSOR_GETTER, - ACCESSOR_SETTER -}; - - -// JSReceiver includes types on which properties can be defined, i.e., -// JSObject and JSProxy. -class JSReceiver: public HeapObject { - public: - enum DeleteMode { - NORMAL_DELETION, - STRICT_DELETION, - FORCE_DELETION - }; - - // A non-keyed store is of the form a.x = foo or a["x"] = foo whereas - // a keyed store is of the form a[expression] = foo. - enum StoreFromKeyed { - MAY_BE_STORE_FROM_KEYED, - CERTAINLY_NOT_STORE_FROM_KEYED - }; - - // Internal properties (e.g. the hidden properties dictionary) might - // be added even though the receiver is non-extensible. - enum ExtensibilityCheck { - PERFORM_EXTENSIBILITY_CHECK, - OMIT_EXTENSIBILITY_CHECK - }; - - // Casting. - static inline JSReceiver* cast(Object* obj); - - static Handle<Object> SetProperty(Handle<JSReceiver> object, - Handle<String> key, - Handle<Object> value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - bool skip_fallback_interceptor = false); - // Can cause GC. - MUST_USE_RESULT MaybeObject* SetProperty( - String* key, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - StoreFromKeyed store_from_keyed = MAY_BE_STORE_FROM_KEYED, - bool skip_fallback_interceptor = false); - MUST_USE_RESULT MaybeObject* SetProperty( - LookupResult* result, - String* key, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - StoreFromKeyed store_from_keyed = MAY_BE_STORE_FROM_KEYED); - MUST_USE_RESULT MaybeObject* SetPropertyWithDefinedSetter(JSReceiver* setter, - Object* value); - - MUST_USE_RESULT MaybeObject* DeleteProperty(String* name, DeleteMode mode); - MUST_USE_RESULT MaybeObject* DeleteElement(uint32_t index, DeleteMode mode); - - // Set the index'th array element. - // Can cause GC, or return failure if GC is required. - MUST_USE_RESULT MaybeObject* SetElement(uint32_t index, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - bool check_prototype); - - // Tests for the fast common case for property enumeration. - bool IsSimpleEnum(); - - // Returns the class name ([[Class]] property in the specification). - String* class_name(); - - // Returns the constructor name (the name (possibly, inferred name) of the - // function that was used to instantiate the object). - String* constructor_name(); - - inline PropertyAttributes GetPropertyAttribute(String* name); - PropertyAttributes GetPropertyAttributeWithReceiver(JSReceiver* receiver, - String* name); - PropertyAttributes GetLocalPropertyAttribute(String* name); - - inline PropertyAttributes GetElementAttribute(uint32_t index); - inline PropertyAttributes GetLocalElementAttribute(uint32_t index); - - // Can cause a GC. - inline bool HasProperty(String* name); - inline bool HasLocalProperty(String* name); - inline bool HasElement(uint32_t index); - inline bool HasLocalElement(uint32_t index); - - // Return the object's prototype (might be Heap::null_value()). - inline Object* GetPrototype(); - - // Return the constructor function (may be Heap::null_value()). - inline Object* GetConstructor(); - - // Set the object's prototype (only JSReceiver and null are allowed). - MUST_USE_RESULT MaybeObject* SetPrototype(Object* value, - bool skip_hidden_prototypes); - - // Retrieves a permanent object identity hash code. The undefined value might - // be returned in case no hash was created yet and OMIT_CREATION was used. - inline MUST_USE_RESULT MaybeObject* GetIdentityHash(CreationFlag flag); - - // Lookup a property. If found, the result is valid and has - // detailed information. - void LocalLookup(String* name, LookupResult* result, - bool search_hidden_prototypes = false, - bool skip_fallback_interceptor = false); - void Lookup(String* name, LookupResult* result, - bool skip_fallback_interceptor = false); - - protected: - Smi* GenerateIdentityHash(); - - private: - PropertyAttributes GetPropertyAttributeForResult(JSReceiver* receiver, - LookupResult* result, - String* name, - bool continue_search); - - DISALLOW_IMPLICIT_CONSTRUCTORS(JSReceiver); -}; - -// The JSObject describes real heap allocated JavaScript objects with -// properties. -// Note that the map of JSObject changes during execution to enable inline -// caching. -class JSObject: public JSReceiver { - public: - // [properties]: Backing storage for properties. - // properties is a FixedArray in the fast case and a Dictionary in the - // slow case. - DECL_ACCESSORS(properties, FixedArray) // Get and set fast properties. - inline void initialize_properties(); - inline bool HasFastProperties(); - inline StringDictionary* property_dictionary(); // Gets slow properties. - - // [elements]: The elements (properties with names that are integers). - // - // Elements can be in two general modes: fast and slow. Each mode - // corrensponds to a set of object representations of elements that - // have something in common. - // - // In the fast mode elements is a FixedArray and so each element can - // be quickly accessed. This fact is used in the generated code. The - // elements array can have one of three maps in this mode: - // fixed_array_map, non_strict_arguments_elements_map or - // fixed_cow_array_map (for copy-on-write arrays). In the latter case - // the elements array may be shared by a few objects and so before - // writing to any element the array must be copied. Use - // EnsureWritableFastElements in this case. - // - // In the slow mode the elements is either a NumberDictionary, an - // ExternalArray, or a FixedArray parameter map for a (non-strict) - // arguments object. - DECL_ACCESSORS(elements, FixedArrayBase) - inline void initialize_elements(); - MUST_USE_RESULT inline MaybeObject* ResetElements(); - inline ElementsKind GetElementsKind(); - inline ElementsAccessor* GetElementsAccessor(); - // Returns true if an object has elements of FAST_SMI_ELEMENTS ElementsKind. - inline bool HasFastSmiElements(); - // Returns true if an object has elements of FAST_ELEMENTS ElementsKind. - inline bool HasFastObjectElements(); - // Returns true if an object has elements of FAST_ELEMENTS or - // FAST_SMI_ONLY_ELEMENTS. - inline bool HasFastSmiOrObjectElements(); - // Returns true if an object has any of the fast elements kinds. - inline bool HasFastElements(); - // Returns true if an object has elements of FAST_DOUBLE_ELEMENTS - // ElementsKind. - inline bool HasFastDoubleElements(); - // Returns true if an object has elements of FAST_HOLEY_*_ELEMENTS - // ElementsKind. - inline bool HasFastHoleyElements(); - inline bool HasNonStrictArgumentsElements(); - inline bool HasDictionaryElements(); - inline bool HasExternalPixelElements(); - inline bool HasExternalArrayElements(); - inline bool HasExternalByteElements(); - inline bool HasExternalUnsignedByteElements(); - inline bool HasExternalShortElements(); - inline bool HasExternalUnsignedShortElements(); - inline bool HasExternalIntElements(); - inline bool HasExternalUnsignedIntElements(); - inline bool HasExternalFloatElements(); - inline bool HasExternalDoubleElements(); - bool HasFastArgumentsElements(); - bool HasDictionaryArgumentsElements(); - inline SeededNumberDictionary* element_dictionary(); // Gets slow elements. - - inline void set_map_and_elements( - Map* map, - FixedArrayBase* value, - WriteBarrierMode mode = UPDATE_WRITE_BARRIER); - - // Requires: HasFastElements(). - MUST_USE_RESULT inline MaybeObject* EnsureWritableFastElements(); - - // Collects elements starting at index 0. - // Undefined values are placed after non-undefined values. - // Returns the number of non-undefined values. - MUST_USE_RESULT MaybeObject* PrepareElementsForSort(uint32_t limit); - // As PrepareElementsForSort, but only on objects where elements is - // a dictionary, and it will stay a dictionary. - MUST_USE_RESULT MaybeObject* PrepareSlowElementsForSort(uint32_t limit); - - MUST_USE_RESULT MaybeObject* GetPropertyWithCallback(Object* receiver, - Object* structure, - String* name); - - // Can cause GC. - MUST_USE_RESULT MaybeObject* SetPropertyForResult(LookupResult* result, - String* key, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - StoreFromKeyed store_mode); - MUST_USE_RESULT MaybeObject* SetPropertyWithFailedAccessCheck( - LookupResult* result, - String* name, - Object* value, - bool check_prototype, - StrictModeFlag strict_mode); - MUST_USE_RESULT MaybeObject* SetPropertyWithCallback( - Object* structure, - String* name, - Object* value, - JSObject* holder, - StrictModeFlag strict_mode); - MUST_USE_RESULT MaybeObject* SetPropertyWithInterceptor( - String* name, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode); - MUST_USE_RESULT MaybeObject* SetPropertyPostInterceptor( - String* name, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - ExtensibilityCheck extensibility_check); - - static Handle<Object> SetLocalPropertyIgnoreAttributes( - Handle<JSObject> object, - Handle<String> key, - Handle<Object> value, - PropertyAttributes attributes); - - // Try to follow an existing transition to a field with attributes NONE. The - // return value indicates whether the transition was successful. - static inline bool TryTransitionToField(Handle<JSObject> object, - Handle<String> key); - - inline int LastAddedFieldIndex(); - - // Extend the receiver with a single fast property appeared first in the - // passed map. This also extends the property backing store if necessary. - static void AddFastPropertyUsingMap(Handle<JSObject> object, Handle<Map> map); - inline MUST_USE_RESULT MaybeObject* AddFastPropertyUsingMap(Map* map); - - // Can cause GC. - MUST_USE_RESULT MaybeObject* SetLocalPropertyIgnoreAttributes( - String* key, - Object* value, - PropertyAttributes attributes); - - // Retrieve a value in a normalized object given a lookup result. - // Handles the special representation of JS global objects. - Object* GetNormalizedProperty(LookupResult* result); - - // Sets the property value in a normalized object given a lookup result. - // Handles the special representation of JS global objects. - Object* SetNormalizedProperty(LookupResult* result, Object* value); - - // Sets the property value in a normalized object given (key, value, details). - // Handles the special representation of JS global objects. - static Handle<Object> SetNormalizedProperty(Handle<JSObject> object, - Handle<String> key, - Handle<Object> value, - PropertyDetails details); - - MUST_USE_RESULT MaybeObject* SetNormalizedProperty(String* name, - Object* value, - PropertyDetails details); - - // Deletes the named property in a normalized object. - MUST_USE_RESULT MaybeObject* DeleteNormalizedProperty(String* name, - DeleteMode mode); - - MUST_USE_RESULT MaybeObject* OptimizeAsPrototype(); - - // Retrieve interceptors. - InterceptorInfo* GetNamedInterceptor(); - InterceptorInfo* GetIndexedInterceptor(); - - // Used from JSReceiver. - PropertyAttributes GetPropertyAttributePostInterceptor(JSObject* receiver, - String* name, - bool continue_search); - PropertyAttributes GetPropertyAttributeWithInterceptor(JSObject* receiver, - String* name, - bool continue_search); - PropertyAttributes GetPropertyAttributeWithFailedAccessCheck( - Object* receiver, - LookupResult* result, - String* name, - bool continue_search); - PropertyAttributes GetElementAttributeWithReceiver(JSReceiver* receiver, - uint32_t index, - bool continue_search); - - static void DefineAccessor(Handle<JSObject> object, - Handle<String> name, - Handle<Object> getter, - Handle<Object> setter, - PropertyAttributes attributes); - // Can cause GC. - MUST_USE_RESULT MaybeObject* DefineAccessor(String* name, - Object* getter, - Object* setter, - PropertyAttributes attributes); - // Try to define a single accessor paying attention to map transitions. - // Returns a JavaScript null if this was not possible and we have to use the - // slow case. Note that we can fail due to allocations, too. - MUST_USE_RESULT MaybeObject* DefineFastAccessor( - String* name, - AccessorComponent component, - Object* accessor, - PropertyAttributes attributes); - Object* LookupAccessor(String* name, AccessorComponent component); - - MUST_USE_RESULT MaybeObject* DefineAccessor(AccessorInfo* info); - - // Used from Object::GetProperty(). - MUST_USE_RESULT MaybeObject* GetPropertyWithFailedAccessCheck( - Object* receiver, - LookupResult* result, - String* name, - PropertyAttributes* attributes); - MUST_USE_RESULT MaybeObject* GetPropertyWithInterceptor( - Object* receiver, - String* name, - PropertyAttributes* attributes); - MUST_USE_RESULT MaybeObject* GetPropertyPostInterceptor( - Object* receiver, - String* name, - PropertyAttributes* attributes); - MUST_USE_RESULT MaybeObject* GetLocalPropertyPostInterceptor( - Object* receiver, - String* name, - PropertyAttributes* attributes); - - // Returns true if this is an instance of an api function and has - // been modified since it was created. May give false positives. - bool IsDirty(); - - // If the receiver is a JSGlobalProxy this method will return its prototype, - // otherwise the result is the receiver itself. - inline Object* BypassGlobalProxy(); - - // Accessors for hidden properties object. - // - // Hidden properties are not local properties of the object itself. - // Instead they are stored in an auxiliary structure kept as a local - // property with a special name Heap::hidden_string(). But if the - // receiver is a JSGlobalProxy then the auxiliary object is a property - // of its prototype, and if it's a detached proxy, then you can't have - // hidden properties. - - // Sets a hidden property on this object. Returns this object if successful, - // undefined if called on a detached proxy. - static Handle<Object> SetHiddenProperty(Handle<JSObject> obj, - Handle<String> key, - Handle<Object> value); - // Returns a failure if a GC is required. - MUST_USE_RESULT MaybeObject* SetHiddenProperty(String* key, Object* value); - // Gets the value of a hidden property with the given key. Returns undefined - // if the property doesn't exist (or if called on a detached proxy), - // otherwise returns the value set for the key. - Object* GetHiddenProperty(String* key); - // Deletes a hidden property. Deleting a non-existing property is - // considered successful. - void DeleteHiddenProperty(String* key); - // Returns true if the object has a property with the hidden string as name. - bool HasHiddenProperties(); - - static int GetIdentityHash(Handle<JSObject> obj); - MUST_USE_RESULT MaybeObject* GetIdentityHash(CreationFlag flag); - MUST_USE_RESULT MaybeObject* SetIdentityHash(Smi* hash, CreationFlag flag); - - static Handle<Object> DeleteProperty(Handle<JSObject> obj, - Handle<String> name); - // Can cause GC. - MUST_USE_RESULT MaybeObject* DeleteProperty(String* name, DeleteMode mode); - - static Handle<Object> DeleteElement(Handle<JSObject> obj, uint32_t index); - MUST_USE_RESULT MaybeObject* DeleteElement(uint32_t index, DeleteMode mode); - - inline void ValidateElements(); - - // Makes sure that this object can contain HeapObject as elements. - MUST_USE_RESULT inline MaybeObject* EnsureCanContainHeapObjectElements(); - - // Makes sure that this object can contain the specified elements. - MUST_USE_RESULT inline MaybeObject* EnsureCanContainElements( - Object** elements, - uint32_t count, - EnsureElementsMode mode); - MUST_USE_RESULT inline MaybeObject* EnsureCanContainElements( - FixedArrayBase* elements, - uint32_t length, - EnsureElementsMode mode); - MUST_USE_RESULT MaybeObject* EnsureCanContainElements( - Arguments* arguments, - uint32_t first_arg, - uint32_t arg_count, - EnsureElementsMode mode); - - // Do we want to keep the elements in fast case when increasing the - // capacity? - bool ShouldConvertToSlowElements(int new_capacity); - // Returns true if the backing storage for the slow-case elements of - // this object takes up nearly as much space as a fast-case backing - // storage would. In that case the JSObject should have fast - // elements. - bool ShouldConvertToFastElements(); - // Returns true if the elements of JSObject contains only values that can be - // represented in a FixedDoubleArray and has at least one value that can only - // be represented as a double and not a Smi. - bool ShouldConvertToFastDoubleElements(bool* has_smi_only_elements); - - // Computes the new capacity when expanding the elements of a JSObject. - static int NewElementsCapacity(int old_capacity) { - // (old_capacity + 50%) + 16 - return old_capacity + (old_capacity >> 1) + 16; - } - - PropertyType GetLocalPropertyType(String* name); - PropertyType GetLocalElementType(uint32_t index); - - // These methods do not perform access checks! - AccessorPair* GetLocalPropertyAccessorPair(String* name); - AccessorPair* GetLocalElementAccessorPair(uint32_t index); - - MUST_USE_RESULT MaybeObject* SetFastElement(uint32_t index, - Object* value, - StrictModeFlag strict_mode, - bool check_prototype); - - MUST_USE_RESULT MaybeObject* SetDictionaryElement( - uint32_t index, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - bool check_prototype, - SetPropertyMode set_mode = SET_PROPERTY); - - MUST_USE_RESULT MaybeObject* SetFastDoubleElement( - uint32_t index, - Object* value, - StrictModeFlag strict_mode, - bool check_prototype = true); - - static Handle<Object> SetOwnElement(Handle<JSObject> object, - uint32_t index, - Handle<Object> value, - StrictModeFlag strict_mode); - - // Empty handle is returned if the element cannot be set to the given value. - static Handle<Object> SetElement( - Handle<JSObject> object, - uint32_t index, - Handle<Object> value, - PropertyAttributes attr, - StrictModeFlag strict_mode, - SetPropertyMode set_mode = SET_PROPERTY); - - // A Failure object is returned if GC is needed. - MUST_USE_RESULT MaybeObject* SetElement( - uint32_t index, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - bool check_prototype = true, - SetPropertyMode set_mode = SET_PROPERTY); - - // Returns the index'th element. - // The undefined object if index is out of bounds. - MUST_USE_RESULT MaybeObject* GetElementWithInterceptor(Object* receiver, - uint32_t index); - - enum SetFastElementsCapacitySmiMode { - kAllowSmiElements, - kForceSmiElements, - kDontAllowSmiElements - }; - - // Replace the elements' backing store with fast elements of the given - // capacity. Update the length for JSArrays. Returns the new backing - // store. - MUST_USE_RESULT MaybeObject* SetFastElementsCapacityAndLength( - int capacity, - int length, - SetFastElementsCapacitySmiMode smi_mode); - MUST_USE_RESULT MaybeObject* SetFastDoubleElementsCapacityAndLength( - int capacity, - int length); - - // Lookup interceptors are used for handling properties controlled by host - // objects. - inline bool HasNamedInterceptor(); - inline bool HasIndexedInterceptor(); - - // Support functions for v8 api (needed for correct interceptor behavior). - bool HasRealNamedProperty(String* key); - bool HasRealElementProperty(uint32_t index); - bool HasRealNamedCallbackProperty(String* key); - - // Get the header size for a JSObject. Used to compute the index of - // internal fields as well as the number of internal fields. - inline int GetHeaderSize(); - - inline int GetInternalFieldCount(); - inline int GetInternalFieldOffset(int index); - inline Object* GetInternalField(int index); - inline void SetInternalField(int index, Object* value); - inline void SetInternalField(int index, Smi* value); - - inline void SetExternalResourceObject(Object* value); - inline Object *GetExternalResourceObject(); - - // The following lookup functions skip interceptors. - void LocalLookupRealNamedProperty(String* name, LookupResult* result); - void LookupRealNamedProperty(String* name, LookupResult* result); - void LookupRealNamedPropertyInPrototypes(String* name, LookupResult* result); - MUST_USE_RESULT MaybeObject* SetElementWithCallbackSetterInPrototypes( - uint32_t index, Object* value, bool* found, StrictModeFlag strict_mode); - void LookupCallbackProperty(String* name, LookupResult* result); - - // Returns the number of properties on this object filtering out properties - // with the specified attributes (ignoring interceptors). - int NumberOfLocalProperties(PropertyAttributes filter = NONE); - // Fill in details for properties into storage starting at the specified - // index. - void GetLocalPropertyNames(FixedArray* storage, int index); - - // Returns the number of properties on this object filtering out properties - // with the specified attributes (ignoring interceptors). - int NumberOfLocalElements(PropertyAttributes filter); - // Returns the number of enumerable elements (ignoring interceptors). - int NumberOfEnumElements(); - // Returns the number of elements on this object filtering out elements - // with the specified attributes (ignoring interceptors). - int GetLocalElementKeys(FixedArray* storage, PropertyAttributes filter); - // Count and fill in the enumerable elements into storage. - // (storage->length() == NumberOfEnumElements()). - // If storage is NULL, will count the elements without adding - // them to any storage. - // Returns the number of enumerable elements. - int GetEnumElementKeys(FixedArray* storage); - - // Add a property to a fast-case object using a map transition to - // new_map. - MUST_USE_RESULT MaybeObject* AddFastPropertyUsingMap(Map* new_map, - String* name, - Object* value, - int field_index); - - // Add a constant function property to a fast-case object. - // This leaves a CONSTANT_TRANSITION in the old map, and - // if it is called on a second object with this map, a - // normal property is added instead, with a map transition. - // This avoids the creation of many maps with the same constant - // function, all orphaned. - MUST_USE_RESULT MaybeObject* AddConstantFunctionProperty( - String* name, - JSFunction* function, - PropertyAttributes attributes); - - MUST_USE_RESULT MaybeObject* ReplaceSlowProperty( - String* name, - Object* value, - PropertyAttributes attributes); - - // Returns a new map with all transitions dropped from the object's current - // map and the ElementsKind set. - static Handle<Map> GetElementsTransitionMap(Handle<JSObject> object, - ElementsKind to_kind); - inline MUST_USE_RESULT MaybeObject* GetElementsTransitionMap( - Isolate* isolate, - ElementsKind elements_kind); - MUST_USE_RESULT MaybeObject* GetElementsTransitionMapSlow( - ElementsKind elements_kind); - - static Handle<Object> TransitionElementsKind(Handle<JSObject> object, - ElementsKind to_kind); - - MUST_USE_RESULT MaybeObject* TransitionElementsKind(ElementsKind to_kind); - MUST_USE_RESULT MaybeObject* UpdateAllocationSiteInfo( - ElementsKind to_kind); - - // Replaces an existing transition with a transition to a map with a FIELD. - MUST_USE_RESULT MaybeObject* ConvertTransitionToMapTransition( - int transition_index, - String* name, - Object* new_value, - PropertyAttributes attributes); - - // Converts a descriptor of any other type to a real field, backed by the - // properties array. - MUST_USE_RESULT MaybeObject* ConvertDescriptorToField( - String* name, - Object* new_value, - PropertyAttributes attributes); - - // Add a property to a fast-case object. - MUST_USE_RESULT MaybeObject* AddFastProperty( - String* name, - Object* value, - PropertyAttributes attributes, - StoreFromKeyed store_mode = MAY_BE_STORE_FROM_KEYED); - - // Add a property to a slow-case object. - MUST_USE_RESULT MaybeObject* AddSlowProperty(String* name, - Object* value, - PropertyAttributes attributes); - - // Add a property to an object. May cause GC. - MUST_USE_RESULT MaybeObject* AddProperty( - String* name, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - StoreFromKeyed store_mode = MAY_BE_STORE_FROM_KEYED, - ExtensibilityCheck extensibility_check = PERFORM_EXTENSIBILITY_CHECK); - - // Convert the object to use the canonical dictionary - // representation. If the object is expected to have additional properties - // added this number can be indicated to have the backing store allocated to - // an initial capacity for holding these properties. - static void NormalizeProperties(Handle<JSObject> object, - PropertyNormalizationMode mode, - int expected_additional_properties); - - MUST_USE_RESULT MaybeObject* NormalizeProperties( - PropertyNormalizationMode mode, - int expected_additional_properties); - - // Convert and update the elements backing store to be a - // SeededNumberDictionary dictionary. Returns the backing after conversion. - static Handle<SeededNumberDictionary> NormalizeElements( - Handle<JSObject> object); - - MUST_USE_RESULT MaybeObject* NormalizeElements(); - - static void UpdateMapCodeCache(Handle<JSObject> object, - Handle<String> name, - Handle<Code> code); - - MUST_USE_RESULT MaybeObject* UpdateMapCodeCache(String* name, Code* code); - - // Transform slow named properties to fast variants. - // Returns failure if allocation failed. - static void TransformToFastProperties(Handle<JSObject> object, - int unused_property_fields); - - MUST_USE_RESULT MaybeObject* TransformToFastProperties( - int unused_property_fields); - - // Access fast-case object properties at index. - inline Object* FastPropertyAt(int index); - inline Object* FastPropertyAtPut(int index, Object* value); - - // Access to in object properties. - inline int GetInObjectPropertyOffset(int index); - inline Object* InObjectPropertyAt(int index); - inline Object* InObjectPropertyAtPut(int index, - Object* value, - WriteBarrierMode mode - = UPDATE_WRITE_BARRIER); - - // Initializes the body after properties slot, properties slot is - // initialized by set_properties. Fill the pre-allocated fields with - // pre_allocated_value and the rest with filler_value. - // Note: this call does not update write barrier, the caller is responsible - // to ensure that |filler_value| can be collected without WB here. - inline void InitializeBody(Map* map, - Object* pre_allocated_value, - Object* filler_value); - - // Check whether this object references another object - bool ReferencesObject(Object* obj); - - // Casting. - static inline JSObject* cast(Object* obj); - - // Disalow further properties to be added to the object. - static Handle<Object> PreventExtensions(Handle<JSObject> object); - MUST_USE_RESULT MaybeObject* PreventExtensions(); - - - // Dispatched behavior. - void JSObjectShortPrint(StringStream* accumulator); - DECLARE_PRINTER(JSObject) - DECLARE_VERIFIER(JSObject) -#ifdef OBJECT_PRINT - inline void PrintProperties() { - PrintProperties(stdout); - } - void PrintProperties(FILE* out); - - inline void PrintElements() { - PrintElements(stdout); - } - void PrintElements(FILE* out); - inline void PrintTransitions() { - PrintTransitions(stdout); - } - void PrintTransitions(FILE* out); -#endif - - void PrintElementsTransition( - FILE* file, ElementsKind from_kind, FixedArrayBase* from_elements, - ElementsKind to_kind, FixedArrayBase* to_elements); - -#ifdef DEBUG - // Structure for collecting spill information about JSObjects. - class SpillInformation { - public: - void Clear(); - void Print(); - int number_of_objects_; - int number_of_objects_with_fast_properties_; - int number_of_objects_with_fast_elements_; - int number_of_fast_used_fields_; - int number_of_fast_unused_fields_; - int number_of_slow_used_properties_; - int number_of_slow_unused_properties_; - int number_of_fast_used_elements_; - int number_of_fast_unused_elements_; - int number_of_slow_used_elements_; - int number_of_slow_unused_elements_; - }; - - void IncrementSpillStatistics(SpillInformation* info); -#endif - Object* SlowReverseLookup(Object* value); - - // Maximal number of fast properties for the JSObject. Used to - // restrict the number of map transitions to avoid an explosion in - // the number of maps for objects used as dictionaries. - inline bool TooManyFastProperties(int properties, StoreFromKeyed store_mode); - - // Maximal number of elements (numbered 0 .. kMaxElementCount - 1). - // Also maximal value of JSArray's length property. - static const uint32_t kMaxElementCount = 0xffffffffu; - - // Constants for heuristics controlling conversion of fast elements - // to slow elements. - - // Maximal gap that can be introduced by adding an element beyond - // the current elements length. - static const uint32_t kMaxGap = 1024; - - // Maximal length of fast elements array that won't be checked for - // being dense enough on expansion. - static const int kMaxUncheckedFastElementsLength = 5000; - - // Same as above but for old arrays. This limit is more strict. We - // don't want to be wasteful with long lived objects. - static const int kMaxUncheckedOldFastElementsLength = 500; - - static const int kInitialMaxFastElementArray = 100000; - static const int kFastPropertiesSoftLimit = 12; - static const int kMaxFastProperties = 64; - static const int kMaxInstanceSize = 255 * kPointerSize; - // When extending the backing storage for property values, we increase - // its size by more than the 1 entry necessary, so sequentially adding fields - // to the same object requires fewer allocations and copies. - static const int kFieldsAdded = 3; - - // Layout description. - static const int kPropertiesOffset = HeapObject::kHeaderSize; - static const int kElementsOffset = kPropertiesOffset + kPointerSize; - static const int kHeaderSize = kElementsOffset + kPointerSize; - - STATIC_CHECK(kHeaderSize == Internals::kJSObjectHeaderSize); - - class BodyDescriptor : public FlexibleBodyDescriptor<kPropertiesOffset> { - public: - static inline int SizeOf(Map* map, HeapObject* object); - }; - - // Enqueue change record for Object.observe. May cause GC. - static void EnqueueChangeRecord(Handle<JSObject> object, - const char* type, - Handle<String> name, - Handle<Object> old_value); - - // Deliver change records to observers. May cause GC. - static void DeliverChangeRecords(Isolate* isolate); - - private: - friend class DictionaryElementsAccessor; - - MUST_USE_RESULT MaybeObject* GetElementWithCallback(Object* receiver, - Object* structure, - uint32_t index, - Object* holder); - MUST_USE_RESULT PropertyAttributes GetElementAttributeWithInterceptor( - JSReceiver* receiver, - uint32_t index, - bool continue_search); - MUST_USE_RESULT PropertyAttributes GetElementAttributeWithoutInterceptor( - JSReceiver* receiver, - uint32_t index, - bool continue_search); - MUST_USE_RESULT MaybeObject* SetElementWithCallback( - Object* structure, - uint32_t index, - Object* value, - JSObject* holder, - StrictModeFlag strict_mode); - MUST_USE_RESULT MaybeObject* SetElementWithInterceptor( - uint32_t index, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - bool check_prototype, - SetPropertyMode set_mode); - MUST_USE_RESULT MaybeObject* SetElementWithoutInterceptor( - uint32_t index, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - bool check_prototype, - SetPropertyMode set_mode); - - // Searches the prototype chain for property 'name'. If it is found and - // has a setter, invoke it and set '*done' to true. If it is found and is - // read-only, reject and set '*done' to true. Otherwise, set '*done' to - // false. Can cause GC and can return a failure result with '*done==true'. - MUST_USE_RESULT MaybeObject* SetPropertyViaPrototypes( - String* name, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - bool* done); - - MUST_USE_RESULT MaybeObject* DeletePropertyPostInterceptor(String* name, - DeleteMode mode); - MUST_USE_RESULT MaybeObject* DeletePropertyWithInterceptor(String* name); - - MUST_USE_RESULT MaybeObject* DeleteElementWithInterceptor(uint32_t index); - - MUST_USE_RESULT MaybeObject* DeleteFastElement(uint32_t index); - MUST_USE_RESULT MaybeObject* DeleteDictionaryElement(uint32_t index, - DeleteMode mode); - - bool ReferencesObjectFromElements(FixedArray* elements, - ElementsKind kind, - Object* object); - - // Returns true if most of the elements backing storage is used. - bool HasDenseElements(); - - // Gets the current elements capacity and the number of used elements. - void GetElementsCapacityAndUsage(int* capacity, int* used); - - bool CanSetCallback(String* name); - MUST_USE_RESULT MaybeObject* SetElementCallback( - uint32_t index, - Object* structure, - PropertyAttributes attributes); - MUST_USE_RESULT MaybeObject* SetPropertyCallback( - String* name, - Object* structure, - PropertyAttributes attributes); - MUST_USE_RESULT MaybeObject* DefineElementAccessor( - uint32_t index, - Object* getter, - Object* setter, - PropertyAttributes attributes); - MUST_USE_RESULT MaybeObject* CreateAccessorPairFor(String* name); - MUST_USE_RESULT MaybeObject* DefinePropertyAccessor( - String* name, - Object* getter, - Object* setter, - PropertyAttributes attributes); - - - enum InitializeHiddenProperties { - CREATE_NEW_IF_ABSENT, - ONLY_RETURN_INLINE_VALUE - }; - - // If create_if_absent is true, return the hash table backing store - // for hidden properties. If there is no backing store, allocate one. - // If create_if_absent is false, return the hash table backing store - // or the inline stored identity hash, whatever is found. - MUST_USE_RESULT MaybeObject* GetHiddenPropertiesHashTable( - InitializeHiddenProperties init_option); - // Set the hidden property backing store to either a hash table or - // the inline-stored identity hash. - MUST_USE_RESULT MaybeObject* SetHiddenPropertiesHashTable( - Object* value); - - DISALLOW_IMPLICIT_CONSTRUCTORS(JSObject); -}; - - -// Common superclass for FixedArrays that allow implementations to share -// common accessors and some code paths. -class FixedArrayBase: public HeapObject { - public: - // [length]: length of the array. - inline int length(); - inline void set_length(int value); - - inline static FixedArrayBase* cast(Object* object); - - // Layout description. - // Length is smi tagged when it is stored. - static const int kLengthOffset = HeapObject::kHeaderSize; - static const int kHeaderSize = kLengthOffset + kPointerSize; -}; - - -class FixedDoubleArray; -class IncrementalMarking; - - -// FixedArray describes fixed-sized arrays with element type Object*. -class FixedArray: public FixedArrayBase { - public: - // Setter and getter for elements. - inline Object* get(int index); - // Setter that uses write barrier. - inline void set(int index, Object* value); - inline bool is_the_hole(int index); - - // Setter that doesn't need write barrier). - inline void set(int index, Smi* value); - // Setter with explicit barrier mode. - inline void set(int index, Object* value, WriteBarrierMode mode); - - // Setters for frequently used oddballs located in old space. - inline void set_undefined(int index); - // TODO(isolates): duplicate. - inline void set_undefined(Heap* heap, int index); - inline void set_null(int index); - // TODO(isolates): duplicate. - inline void set_null(Heap* heap, int index); - inline void set_the_hole(int index); - - // Setters with less debug checks for the GC to use. - inline void set_unchecked(int index, Smi* value); - inline void set_null_unchecked(Heap* heap, int index); - inline void set_unchecked(Heap* heap, int index, Object* value, - WriteBarrierMode mode); - - inline Object** GetFirstElementAddress(); - inline bool ContainsOnlySmisOrHoles(); - - // Gives access to raw memory which stores the array's data. - inline Object** data_start(); - - // Copy operations. - MUST_USE_RESULT inline MaybeObject* Copy(); - MUST_USE_RESULT MaybeObject* CopySize(int new_length); - - // Add the elements of a JSArray to this FixedArray. - MUST_USE_RESULT MaybeObject* AddKeysFromJSArray(JSArray* array); - - // Compute the union of this and other. - MUST_USE_RESULT MaybeObject* UnionOfKeys(FixedArray* other); - - // Copy a sub array from the receiver to dest. - void CopyTo(int pos, FixedArray* dest, int dest_pos, int len); - - // Garbage collection support. - static int SizeFor(int length) { return kHeaderSize + length * kPointerSize; } - - // Code Generation support. - static int OffsetOfElementAt(int index) { return SizeFor(index); } - - // Casting. - static inline FixedArray* cast(Object* obj); - - // Maximal allowed size, in bytes, of a single FixedArray. - // Prevents overflowing size computations, as well as extreme memory - // consumption. - static const int kMaxSize = 128 * MB * kPointerSize; - // Maximally allowed length of a FixedArray. - static const int kMaxLength = (kMaxSize - kHeaderSize) / kPointerSize; - - // Dispatched behavior. - DECLARE_PRINTER(FixedArray) - DECLARE_VERIFIER(FixedArray) -#ifdef DEBUG - // Checks if two FixedArrays have identical contents. - bool IsEqualTo(FixedArray* other); -#endif - - // Swap two elements in a pair of arrays. If this array and the - // numbers array are the same object, the elements are only swapped - // once. - void SwapPairs(FixedArray* numbers, int i, int j); - - // Sort prefix of this array and the numbers array as pairs wrt. the - // numbers. If the numbers array and the this array are the same - // object, the prefix of this array is sorted. - void SortPairs(FixedArray* numbers, uint32_t len); - - class BodyDescriptor : public FlexibleBodyDescriptor<kHeaderSize> { - public: - static inline int SizeOf(Map* map, HeapObject* object) { - return SizeFor(reinterpret_cast<FixedArray*>(object)->length()); - } - }; - - protected: - // Set operation on FixedArray without using write barriers. Can - // only be used for storing old space objects or smis. - static inline void NoWriteBarrierSet(FixedArray* array, - int index, - Object* value); - - // Set operation on FixedArray without incremental write barrier. Can - // only be used if the object is guaranteed to be white (whiteness witness - // is present). - static inline void NoIncrementalWriteBarrierSet(FixedArray* array, - int index, - Object* value); - - private: - STATIC_CHECK(kHeaderSize == Internals::kFixedArrayHeaderSize); - - DISALLOW_IMPLICIT_CONSTRUCTORS(FixedArray); -}; - - -// FixedDoubleArray describes fixed-sized arrays with element type double. -class FixedDoubleArray: public FixedArrayBase { - public: - // Setter and getter for elements. - inline double get_scalar(int index); - inline int64_t get_representation(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, double value); - inline void set_the_hole(int index); - - // Checking for the hole. - inline bool is_the_hole(int index); - - // Copy operations - MUST_USE_RESULT inline MaybeObject* Copy(); - - // Garbage collection support. - inline static int SizeFor(int length) { - return kHeaderSize + length * kDoubleSize; - } - - // Gives access to raw memory which stores the array's data. - inline double* data_start(); - - // Code Generation support. - static int OffsetOfElementAt(int index) { return SizeFor(index); } - - inline static bool is_the_hole_nan(double value); - inline static double hole_nan_as_double(); - inline static double canonical_not_the_hole_nan_as_double(); - - // Casting. - static inline FixedDoubleArray* cast(Object* obj); - - // Maximal allowed size, in bytes, of a single FixedDoubleArray. - // Prevents overflowing size computations, as well as extreme memory - // consumption. - static const int kMaxSize = 512 * MB; - // Maximally allowed length of a FixedArray. - static const int kMaxLength = (kMaxSize - kHeaderSize) / kDoubleSize; - - // Dispatched behavior. - DECLARE_PRINTER(FixedDoubleArray) - DECLARE_VERIFIER(FixedDoubleArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(FixedDoubleArray); -}; - - -// DescriptorArrays are fixed arrays used to hold instance descriptors. -// The format of the these objects is: -// [0]: Number of descriptors -// [1]: Either Smi(0) if uninitialized, or a pointer to small fixed array: -// [0]: pointer to fixed array with enum cache -// [1]: either Smi(0) or pointer to fixed array with indices -// [2]: first key -// [2 + number of descriptors * kDescriptorSize]: start of slack -class DescriptorArray: public FixedArray { - public: - // WhitenessWitness is used to prove that a descriptor array is white - // (unmarked), so incremental write barriers can be skipped because the - // marking invariant cannot be broken and slots pointing into evacuation - // candidates will be discovered when the object is scanned. A witness is - // always stack-allocated right after creating an array. By allocating a - // witness, incremental marking is globally disabled. The witness is then - // passed along wherever needed to statically prove that the array is known to - // be white. - class WhitenessWitness { - public: - inline explicit WhitenessWitness(FixedArray* array); - inline ~WhitenessWitness(); - - private: - IncrementalMarking* marking_; - }; - - // Returns true for both shared empty_descriptor_array and for smis, which the - // map uses to encode additional bit fields when the descriptor array is not - // yet used. - inline bool IsEmpty(); - - // Returns the number of descriptors in the array. - int number_of_descriptors() { - ASSERT(length() >= kFirstIndex || IsEmpty()); - int len = length(); - return len == 0 ? 0 : Smi::cast(get(kDescriptorLengthIndex))->value(); - } - - int number_of_descriptors_storage() { - int len = length(); - return len == 0 ? 0 : (len - kFirstIndex) / kDescriptorSize; - } - - int NumberOfSlackDescriptors() { - return number_of_descriptors_storage() - number_of_descriptors(); - } - - inline void SetNumberOfDescriptors(int number_of_descriptors); - inline int number_of_entries() { return number_of_descriptors(); } - - bool HasEnumCache() { - return !IsEmpty() && !get(kEnumCacheIndex)->IsSmi(); - } - - void CopyEnumCacheFrom(DescriptorArray* array) { - set(kEnumCacheIndex, array->get(kEnumCacheIndex)); - } - - FixedArray* GetEnumCache() { - ASSERT(HasEnumCache()); - FixedArray* bridge = FixedArray::cast(get(kEnumCacheIndex)); - return FixedArray::cast(bridge->get(kEnumCacheBridgeCacheIndex)); - } - - bool HasEnumIndicesCache() { - if (IsEmpty()) return false; - Object* object = get(kEnumCacheIndex); - if (object->IsSmi()) return false; - FixedArray* bridge = FixedArray::cast(object); - return !bridge->get(kEnumCacheBridgeIndicesCacheIndex)->IsSmi(); - } - - FixedArray* GetEnumIndicesCache() { - ASSERT(HasEnumIndicesCache()); - FixedArray* bridge = FixedArray::cast(get(kEnumCacheIndex)); - return FixedArray::cast(bridge->get(kEnumCacheBridgeIndicesCacheIndex)); - } - - Object** GetEnumCacheSlot() { - ASSERT(HasEnumCache()); - return HeapObject::RawField(reinterpret_cast<HeapObject*>(this), - kEnumCacheOffset); - } - - void ClearEnumCache(); - - // Initialize or change the enum cache, - // using the supplied storage for the small "bridge". - void SetEnumCache(FixedArray* bridge_storage, - FixedArray* new_cache, - Object* new_index_cache); - - // Accessors for fetching instance descriptor at descriptor number. - inline String* GetKey(int descriptor_number); - inline Object** GetKeySlot(int descriptor_number); - inline Object* GetValue(int descriptor_number); - inline Object** GetValueSlot(int descriptor_number); - inline Object** GetDescriptorStartSlot(int descriptor_number); - inline Object** GetDescriptorEndSlot(int descriptor_number); - inline PropertyDetails GetDetails(int descriptor_number); - inline PropertyType GetType(int descriptor_number); - inline int GetFieldIndex(int descriptor_number); - inline JSFunction* GetConstantFunction(int descriptor_number); - inline Object* GetCallbacksObject(int descriptor_number); - inline AccessorDescriptor* GetCallbacks(int descriptor_number); - - inline String* GetSortedKey(int descriptor_number); - inline int GetSortedKeyIndex(int descriptor_number); - inline void SetSortedKey(int pointer, int descriptor_number); - - // Accessor for complete descriptor. - inline void Get(int descriptor_number, Descriptor* desc); - inline void Set(int descriptor_number, - Descriptor* desc, - const WhitenessWitness&); - inline void Set(int descriptor_number, Descriptor* desc); - - // Append automatically sets the enumeration index. This should only be used - // to add descriptors in bulk at the end, followed by sorting the descriptor - // array. - inline void Append(Descriptor* desc, const WhitenessWitness&); - inline void Append(Descriptor* desc); - - // Transfer a complete descriptor from the src descriptor array to this - // descriptor array. - void CopyFrom(int dst_index, - DescriptorArray* src, - int src_index, - const WhitenessWitness&); - - MUST_USE_RESULT MaybeObject* CopyUpTo(int enumeration_index); - - // Sort the instance descriptors by the hash codes of their keys. - void Sort(); - - // Search the instance descriptors for given name. - INLINE(int Search(String* name, int number_of_own_descriptors)); - - // As the above, but uses DescriptorLookupCache and updates it when - // necessary. - INLINE(int SearchWithCache(String* name, Map* map)); - - // Allocates a DescriptorArray, but returns the singleton - // empty descriptor array object if number_of_descriptors is 0. - MUST_USE_RESULT static MaybeObject* Allocate(int number_of_descriptors, - int slack = 0); - - // Casting. - static inline DescriptorArray* cast(Object* obj); - - // Constant for denoting key was not found. - static const int kNotFound = -1; - - static const int kDescriptorLengthIndex = 0; - static const int kEnumCacheIndex = 1; - static const int kFirstIndex = 2; - - // The length of the "bridge" to the enum cache. - static const int kEnumCacheBridgeLength = 2; - static const int kEnumCacheBridgeCacheIndex = 0; - static const int kEnumCacheBridgeIndicesCacheIndex = 1; - - // Layout description. - static const int kDescriptorLengthOffset = FixedArray::kHeaderSize; - static const int kEnumCacheOffset = kDescriptorLengthOffset + kPointerSize; - static const int kFirstOffset = kEnumCacheOffset + kPointerSize; - - // Layout description for the bridge array. - static const int kEnumCacheBridgeCacheOffset = FixedArray::kHeaderSize; - - // Layout of descriptor. - static const int kDescriptorKey = 0; - static const int kDescriptorDetails = 1; - static const int kDescriptorValue = 2; - static const int kDescriptorSize = 3; - -#ifdef OBJECT_PRINT - // Print all the descriptors. - inline void PrintDescriptors() { - PrintDescriptors(stdout); - } - void PrintDescriptors(FILE* out); -#endif - -#ifdef DEBUG - // Is the descriptor array sorted and without duplicates? - bool IsSortedNoDuplicates(int valid_descriptors = -1); - - // Is the descriptor array consistent with the back pointers in targets? - bool IsConsistentWithBackPointers(Map* current_map); - - // Are two DescriptorArrays equal? - bool IsEqualTo(DescriptorArray* other); -#endif - - // The maximum number of descriptors we want in a descriptor array (should - // fit in a page). - static const int kMaxNumberOfDescriptors = 1024 + 512; - - // Returns the fixed array length required to hold number_of_descriptors - // descriptors. - static int LengthFor(int number_of_descriptors) { - return ToKeyIndex(number_of_descriptors); - } - - private: - // An entry in a DescriptorArray, represented as an (array, index) pair. - class Entry { - public: - inline explicit Entry(DescriptorArray* descs, int index) : - descs_(descs), index_(index) { } - - inline PropertyType type() { return descs_->GetType(index_); } - inline Object* GetCallbackObject() { return descs_->GetValue(index_); } - - private: - DescriptorArray* descs_; - int index_; - }; - - // Conversion from descriptor number to array indices. - static int ToKeyIndex(int descriptor_number) { - return kFirstIndex + - (descriptor_number * kDescriptorSize) + - kDescriptorKey; - } - - static int ToDetailsIndex(int descriptor_number) { - return kFirstIndex + - (descriptor_number * kDescriptorSize) + - kDescriptorDetails; - } - - static int ToValueIndex(int descriptor_number) { - return kFirstIndex + - (descriptor_number * kDescriptorSize) + - kDescriptorValue; - } - - // Swap first and second descriptor. - inline void SwapSortedKeys(int first, int second); - - DISALLOW_IMPLICIT_CONSTRUCTORS(DescriptorArray); -}; - - -enum SearchMode { ALL_ENTRIES, VALID_ENTRIES }; - -template<SearchMode search_mode, typename T> -inline int LinearSearch(T* array, String* name, int len, int valid_entries); - - -template<SearchMode search_mode, typename T> -inline int Search(T* array, String* name, int valid_entries = 0); - - -// HashTable is a subclass of FixedArray that implements a hash table -// that uses open addressing and quadratic probing. -// -// In order for the quadratic probing to work, elements that have not -// yet been used and elements that have been deleted are -// distinguished. Probing continues when deleted elements are -// encountered and stops when unused elements are encountered. -// -// - Elements with key == undefined have not been used yet. -// - Elements with key == the_hole have been deleted. -// -// The hash table class is parameterized with a Shape and a Key. -// Shape must be a class with the following interface: -// class ExampleShape { -// public: -// // Tells whether key matches other. -// static bool IsMatch(Key key, Object* other); -// // Returns the hash value for key. -// static uint32_t Hash(Key key); -// // Returns the hash value for object. -// static uint32_t HashForObject(Key key, Object* object); -// // Convert key to an object. -// static inline Object* AsObject(Key key); -// // The prefix size indicates number of elements in the beginning -// // of the backing storage. -// static const int kPrefixSize = ..; -// // The Element size indicates number of elements per entry. -// static const int kEntrySize = ..; -// }; -// The prefix size indicates an amount of memory in the -// beginning of the backing storage that can be used for non-element -// information by subclasses. - -template<typename Key> -class BaseShape { - public: - static const bool UsesSeed = false; - static uint32_t Hash(Key key) { return 0; } - static uint32_t SeededHash(Key key, uint32_t seed) { - ASSERT(UsesSeed); - return Hash(key); - } - static uint32_t HashForObject(Key key, Object* object) { return 0; } - static uint32_t SeededHashForObject(Key key, uint32_t seed, Object* object) { - ASSERT(UsesSeed); - return HashForObject(key, object); - } -}; - -template<typename Shape, typename Key> -class HashTable: public FixedArray { - public: - enum MinimumCapacity { - USE_DEFAULT_MINIMUM_CAPACITY, - USE_CUSTOM_MINIMUM_CAPACITY - }; - - // Wrapper methods - inline uint32_t Hash(Key key) { - if (Shape::UsesSeed) { - return Shape::SeededHash(key, - GetHeap()->HashSeed()); - } else { - return Shape::Hash(key); - } - } - - inline uint32_t HashForObject(Key key, Object* object) { - if (Shape::UsesSeed) { - return Shape::SeededHashForObject(key, - GetHeap()->HashSeed(), object); - } else { - return Shape::HashForObject(key, object); - } - } - - // Returns the number of elements in the hash table. - int NumberOfElements() { - return Smi::cast(get(kNumberOfElementsIndex))->value(); - } - - // Returns the number of deleted elements in the hash table. - int NumberOfDeletedElements() { - return Smi::cast(get(kNumberOfDeletedElementsIndex))->value(); - } - - // Returns the capacity of the hash table. - int Capacity() { - return Smi::cast(get(kCapacityIndex))->value(); - } - - // ElementAdded should be called whenever an element is added to a - // hash table. - void ElementAdded() { SetNumberOfElements(NumberOfElements() + 1); } - - // ElementRemoved should be called whenever an element is removed from - // a hash table. - void ElementRemoved() { - SetNumberOfElements(NumberOfElements() - 1); - SetNumberOfDeletedElements(NumberOfDeletedElements() + 1); - } - void ElementsRemoved(int n) { - SetNumberOfElements(NumberOfElements() - n); - SetNumberOfDeletedElements(NumberOfDeletedElements() + n); - } - - // Returns a new HashTable object. Might return Failure. - MUST_USE_RESULT static MaybeObject* Allocate( - int at_least_space_for, - MinimumCapacity capacity_option = USE_DEFAULT_MINIMUM_CAPACITY, - PretenureFlag pretenure = NOT_TENURED); - - // Computes the required capacity for a table holding the given - // number of elements. May be more than HashTable::kMaxCapacity. - static int ComputeCapacity(int at_least_space_for); - - // Returns the key at entry. - Object* KeyAt(int entry) { return get(EntryToIndex(entry)); } - - // Tells whether k is a real key. The hole and undefined are not allowed - // as keys and can be used to indicate missing or deleted elements. - bool IsKey(Object* k) { - return !k->IsTheHole() && !k->IsUndefined(); - } - - // Garbage collection support. - void IteratePrefix(ObjectVisitor* visitor); - void IterateElements(ObjectVisitor* visitor); - - // Casting. - static inline HashTable* cast(Object* obj); - - // Compute the probe offset (quadratic probing). - INLINE(static uint32_t GetProbeOffset(uint32_t n)) { - return (n + n * n) >> 1; - } - - static const int kNumberOfElementsIndex = 0; - static const int kNumberOfDeletedElementsIndex = 1; - static const int kCapacityIndex = 2; - static const int kPrefixStartIndex = 3; - static const int kElementsStartIndex = - kPrefixStartIndex + Shape::kPrefixSize; - static const int kEntrySize = Shape::kEntrySize; - static const int kElementsStartOffset = - kHeaderSize + kElementsStartIndex * kPointerSize; - static const int kCapacityOffset = - kHeaderSize + kCapacityIndex * kPointerSize; - - // Constant used for denoting a absent entry. - static const int kNotFound = -1; - - // Maximal capacity of HashTable. Based on maximal length of underlying - // FixedArray. Staying below kMaxCapacity also ensures that EntryToIndex - // cannot overflow. - static const int kMaxCapacity = - (FixedArray::kMaxLength - kElementsStartOffset) / kEntrySize; - - // Find entry for key otherwise return kNotFound. - inline int FindEntry(Key key); - int FindEntry(Isolate* isolate, Key key); - - protected: - // Find the entry at which to insert element with the given key that - // has the given hash value. - uint32_t FindInsertionEntry(uint32_t hash); - - // Returns the index for an entry (of the key) - static inline int EntryToIndex(int entry) { - return (entry * kEntrySize) + kElementsStartIndex; - } - - // Update the number of elements in the hash table. - void SetNumberOfElements(int nof) { - set(kNumberOfElementsIndex, Smi::FromInt(nof)); - } - - // Update the number of deleted elements in the hash table. - void SetNumberOfDeletedElements(int nod) { - set(kNumberOfDeletedElementsIndex, Smi::FromInt(nod)); - } - - // Sets the capacity of the hash table. - void SetCapacity(int capacity) { - // To scale a computed hash code to fit within the hash table, we - // use bit-wise AND with a mask, so the capacity must be positive - // and non-zero. - ASSERT(capacity > 0); - ASSERT(capacity <= kMaxCapacity); - set(kCapacityIndex, Smi::FromInt(capacity)); - } - - - // Returns probe entry. - static uint32_t GetProbe(uint32_t hash, uint32_t number, uint32_t size) { - ASSERT(IsPowerOf2(size)); - return (hash + GetProbeOffset(number)) & (size - 1); - } - - inline static uint32_t FirstProbe(uint32_t hash, uint32_t size) { - return hash & (size - 1); - } - - inline static uint32_t NextProbe( - uint32_t last, uint32_t number, uint32_t size) { - return (last + number) & (size - 1); - } - - // Rehashes this hash-table into the new table. - MUST_USE_RESULT MaybeObject* Rehash(HashTable* new_table, Key key); - - // Attempt to shrink hash table after removal of key. - MUST_USE_RESULT MaybeObject* Shrink(Key key); - - // Ensure enough space for n additional elements. - MUST_USE_RESULT MaybeObject* EnsureCapacity(int n, Key key); -}; - - -// HashTableKey is an abstract superclass for virtual key behavior. -class HashTableKey { - public: - // Returns whether the other object matches this key. - virtual bool IsMatch(Object* other) = 0; - // Returns the hash value for this key. - virtual uint32_t Hash() = 0; - // Returns the hash value for object. - virtual uint32_t HashForObject(Object* key) = 0; - // Returns the key object for storing into the hash table. - // If allocations fails a failure object is returned. - MUST_USE_RESULT virtual MaybeObject* AsObject() = 0; - // Required. - virtual ~HashTableKey() {} -}; - - -class StringTableShape : public BaseShape<HashTableKey*> { - public: - static inline bool IsMatch(HashTableKey* key, Object* value) { - return key->IsMatch(value); - } - static inline uint32_t Hash(HashTableKey* key) { - return key->Hash(); - } - static inline uint32_t HashForObject(HashTableKey* key, Object* object) { - return key->HashForObject(object); - } - MUST_USE_RESULT static inline MaybeObject* AsObject(HashTableKey* key) { - return key->AsObject(); - } - - static const int kPrefixSize = 0; - static const int kEntrySize = 1; -}; - -class SeqOneByteString; - -// StringTable. -// -// No special elements in the prefix and the element size is 1 -// because only the string itself (the key) needs to be stored. -class StringTable: public HashTable<StringTableShape, HashTableKey*> { - public: - // Find string in the string table. If it is not there yet, it is - // added. The return value is the string table which might have - // been enlarged. If the return value is not a failure, the string - // pointer *s is set to the string found. - MUST_USE_RESULT MaybeObject* LookupUtf8String( - Vector<const char> str, - Object** s); - MUST_USE_RESULT MaybeObject* LookupOneByteString( - Vector<const uint8_t> str, - Object** s); - MUST_USE_RESULT MaybeObject* LookupSubStringOneByteString( - Handle<SeqOneByteString> str, - int from, - int length, - Object** s); - MUST_USE_RESULT MaybeObject* LookupTwoByteString( - Vector<const uc16> str, - Object** s); - MUST_USE_RESULT MaybeObject* LookupString(String* key, Object** s); - - // Looks up a string that is equal to the given string and returns - // true if it is found, assigning the string to the given output - // parameter. - bool LookupStringIfExists(String* str, String** result); - bool LookupTwoCharsStringIfExists(uint16_t c1, uint16_t c2, String** result); - - // Casting. - static inline StringTable* cast(Object* obj); - - private: - MUST_USE_RESULT MaybeObject* LookupKey(HashTableKey* key, Object** s); - - template <bool seq_ascii> friend class JsonParser; - - DISALLOW_IMPLICIT_CONSTRUCTORS(StringTable); -}; - - -class MapCacheShape : public BaseShape<HashTableKey*> { - public: - static inline bool IsMatch(HashTableKey* key, Object* value) { - return key->IsMatch(value); - } - static inline uint32_t Hash(HashTableKey* key) { - return key->Hash(); - } - - static inline uint32_t HashForObject(HashTableKey* key, Object* object) { - return key->HashForObject(object); - } - - MUST_USE_RESULT static inline MaybeObject* AsObject(HashTableKey* key) { - return key->AsObject(); - } - - static const int kPrefixSize = 0; - static const int kEntrySize = 2; -}; - - -// MapCache. -// -// Maps keys that are a fixed array of internalized strings to a map. -// Used for canonicalize maps for object literals. -class MapCache: public HashTable<MapCacheShape, HashTableKey*> { - public: - // Find cached value for a string key, otherwise return null. - Object* Lookup(FixedArray* key); - MUST_USE_RESULT MaybeObject* Put(FixedArray* key, Map* value); - static inline MapCache* cast(Object* obj); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(MapCache); -}; - - -template <typename Shape, typename Key> -class Dictionary: public HashTable<Shape, Key> { - public: - static inline Dictionary<Shape, Key>* cast(Object* obj) { - return reinterpret_cast<Dictionary<Shape, Key>*>(obj); - } - - // Returns the value at entry. - Object* ValueAt(int entry) { - return this->get(HashTable<Shape, Key>::EntryToIndex(entry) + 1); - } - - // Set the value for entry. - void ValueAtPut(int entry, Object* value) { - this->set(HashTable<Shape, Key>::EntryToIndex(entry) + 1, value); - } - - // Returns the property details for the property at entry. - PropertyDetails DetailsAt(int entry) { - ASSERT(entry >= 0); // Not found is -1, which is not caught by get(). - return PropertyDetails( - Smi::cast(this->get(HashTable<Shape, Key>::EntryToIndex(entry) + 2))); - } - - // Set the details for entry. - void DetailsAtPut(int entry, PropertyDetails value) { - this->set(HashTable<Shape, Key>::EntryToIndex(entry) + 2, value.AsSmi()); - } - - // Sorting support - void CopyValuesTo(FixedArray* elements); - - // Delete a property from the dictionary. - Object* DeleteProperty(int entry, JSObject::DeleteMode mode); - - // Attempt to shrink the dictionary after deletion of key. - MUST_USE_RESULT MaybeObject* Shrink(Key key); - - // Returns the number of elements in the dictionary filtering out properties - // with the specified attributes. - int NumberOfElementsFilterAttributes(PropertyAttributes filter); - - // Returns the number of enumerable elements in the dictionary. - int NumberOfEnumElements(); - - enum SortMode { UNSORTED, SORTED }; - // Copies keys to preallocated fixed array. - void CopyKeysTo(FixedArray* storage, - PropertyAttributes filter, - SortMode sort_mode); - // Fill in details for properties into storage. - void CopyKeysTo(FixedArray* storage, int index, SortMode sort_mode); - - // Accessors for next enumeration index. - void SetNextEnumerationIndex(int index) { - ASSERT(index != 0); - this->set(kNextEnumerationIndexIndex, Smi::FromInt(index)); - } - - int NextEnumerationIndex() { - return Smi::cast(FixedArray::get(kNextEnumerationIndexIndex))->value(); - } - - // Returns a new array for dictionary usage. Might return Failure. - MUST_USE_RESULT static MaybeObject* Allocate(int at_least_space_for); - - // Ensure enough space for n additional elements. - MUST_USE_RESULT MaybeObject* EnsureCapacity(int n, Key key); - -#ifdef OBJECT_PRINT - inline void Print() { - Print(stdout); - } - void Print(FILE* out); -#endif - // Returns the key (slow). - Object* SlowReverseLookup(Object* value); - - // Sets the entry to (key, value) pair. - inline void SetEntry(int entry, - Object* key, - Object* value); - inline void SetEntry(int entry, - Object* key, - Object* value, - PropertyDetails details); - - MUST_USE_RESULT MaybeObject* Add(Key key, - Object* value, - PropertyDetails details); - - protected: - // Generic at put operation. - MUST_USE_RESULT MaybeObject* AtPut(Key key, Object* value); - - // Add entry to dictionary. - MUST_USE_RESULT MaybeObject* AddEntry(Key key, - Object* value, - PropertyDetails details, - uint32_t hash); - - // Generate new enumeration indices to avoid enumeration index overflow. - MUST_USE_RESULT MaybeObject* GenerateNewEnumerationIndices(); - static const int kMaxNumberKeyIndex = - HashTable<Shape, Key>::kPrefixStartIndex; - static const int kNextEnumerationIndexIndex = kMaxNumberKeyIndex + 1; -}; - - -class StringDictionaryShape : public BaseShape<String*> { - public: - static inline bool IsMatch(String* key, Object* other); - static inline uint32_t Hash(String* key); - static inline uint32_t HashForObject(String* key, Object* object); - MUST_USE_RESULT static inline MaybeObject* AsObject(String* key); - static const int kPrefixSize = 2; - static const int kEntrySize = 3; - static const bool kIsEnumerable = true; -}; - - -class StringDictionary: public Dictionary<StringDictionaryShape, String*> { - public: - static inline StringDictionary* cast(Object* obj) { - ASSERT(obj->IsDictionary()); - return reinterpret_cast<StringDictionary*>(obj); - } - - // Copies enumerable keys to preallocated fixed array. - FixedArray* CopyEnumKeysTo(FixedArray* storage); - static void DoGenerateNewEnumerationIndices( - Handle<StringDictionary> dictionary); - - // For transforming properties of a JSObject. - MUST_USE_RESULT MaybeObject* TransformPropertiesToFastFor( - JSObject* obj, - int unused_property_fields); - - // Find entry for key, otherwise return kNotFound. Optimized version of - // HashTable::FindEntry. - int FindEntry(String* key); -}; - - -class NumberDictionaryShape : public BaseShape<uint32_t> { - public: - static inline bool IsMatch(uint32_t key, Object* other); - MUST_USE_RESULT static inline MaybeObject* AsObject(uint32_t key); - static const int kEntrySize = 3; - static const bool kIsEnumerable = false; -}; - - -class SeededNumberDictionaryShape : public NumberDictionaryShape { - public: - static const bool UsesSeed = true; - static const int kPrefixSize = 2; - - static inline uint32_t SeededHash(uint32_t key, uint32_t seed); - static inline uint32_t SeededHashForObject(uint32_t key, - uint32_t seed, - Object* object); -}; - - -class UnseededNumberDictionaryShape : public NumberDictionaryShape { - public: - static const int kPrefixSize = 0; - - static inline uint32_t Hash(uint32_t key); - static inline uint32_t HashForObject(uint32_t key, Object* object); -}; - - -class SeededNumberDictionary - : public Dictionary<SeededNumberDictionaryShape, uint32_t> { - public: - static SeededNumberDictionary* cast(Object* obj) { - ASSERT(obj->IsDictionary()); - return reinterpret_cast<SeededNumberDictionary*>(obj); - } - - // Type specific at put (default NONE attributes is used when adding). - MUST_USE_RESULT MaybeObject* AtNumberPut(uint32_t key, Object* value); - MUST_USE_RESULT MaybeObject* AddNumberEntry(uint32_t key, - Object* value, - PropertyDetails details); - - // Set an existing entry or add a new one if needed. - // Return the updated dictionary. - MUST_USE_RESULT static Handle<SeededNumberDictionary> Set( - Handle<SeededNumberDictionary> dictionary, - uint32_t index, - Handle<Object> value, - PropertyDetails details); - - MUST_USE_RESULT MaybeObject* Set(uint32_t key, - Object* value, - PropertyDetails details); - - void UpdateMaxNumberKey(uint32_t key); - - // If slow elements are required we will never go back to fast-case - // for the elements kept in this dictionary. We require slow - // elements if an element has been added at an index larger than - // kRequiresSlowElementsLimit or set_requires_slow_elements() has been called - // when defining a getter or setter with a number key. - inline bool requires_slow_elements(); - inline void set_requires_slow_elements(); - - // Get the value of the max number key that has been added to this - // dictionary. max_number_key can only be called if - // requires_slow_elements returns false. - inline uint32_t max_number_key(); - - // Bit masks. - static const int kRequiresSlowElementsMask = 1; - static const int kRequiresSlowElementsTagSize = 1; - static const uint32_t kRequiresSlowElementsLimit = (1 << 29) - 1; -}; - - -class UnseededNumberDictionary - : public Dictionary<UnseededNumberDictionaryShape, uint32_t> { - public: - static UnseededNumberDictionary* cast(Object* obj) { - ASSERT(obj->IsDictionary()); - return reinterpret_cast<UnseededNumberDictionary*>(obj); - } - - // Type specific at put (default NONE attributes is used when adding). - MUST_USE_RESULT MaybeObject* AtNumberPut(uint32_t key, Object* value); - MUST_USE_RESULT MaybeObject* AddNumberEntry(uint32_t key, Object* value); - - // Set an existing entry or add a new one if needed. - // Return the updated dictionary. - MUST_USE_RESULT static Handle<UnseededNumberDictionary> Set( - Handle<UnseededNumberDictionary> dictionary, - uint32_t index, - Handle<Object> value); - - MUST_USE_RESULT MaybeObject* Set(uint32_t key, Object* value); -}; - - -template <int entrysize> -class ObjectHashTableShape : public BaseShape<Object*> { - public: - static inline bool IsMatch(Object* key, Object* other); - static inline uint32_t Hash(Object* key); - static inline uint32_t HashForObject(Object* key, Object* object); - MUST_USE_RESULT static inline MaybeObject* AsObject(Object* key); - static const int kPrefixSize = 0; - static const int kEntrySize = entrysize; -}; - - -// ObjectHashSet holds keys that are arbitrary objects by using the identity -// hash of the key for hashing purposes. -class ObjectHashSet: public HashTable<ObjectHashTableShape<1>, Object*> { - public: - static inline ObjectHashSet* cast(Object* obj) { - ASSERT(obj->IsHashTable()); - return reinterpret_cast<ObjectHashSet*>(obj); - } - - // Looks up whether the given key is part of this hash set. - bool Contains(Object* key); - - // Adds the given key to this hash set. - MUST_USE_RESULT MaybeObject* Add(Object* key); - - // Removes the given key from this hash set. - MUST_USE_RESULT MaybeObject* Remove(Object* key); -}; - - -// ObjectHashTable maps keys that are arbitrary objects to object values by -// using the identity hash of the key for hashing purposes. -class ObjectHashTable: public HashTable<ObjectHashTableShape<2>, Object*> { - public: - static inline ObjectHashTable* cast(Object* obj) { - ASSERT(obj->IsHashTable()); - return reinterpret_cast<ObjectHashTable*>(obj); - } - - // Looks up the value associated with the given key. The hole value is - // returned in case the key is not present. - Object* Lookup(Object* key); - - // Adds (or overwrites) the value associated with the given key. Mapping a - // key to the hole value causes removal of the whole entry. - MUST_USE_RESULT MaybeObject* Put(Object* key, Object* value); - - private: - friend class MarkCompactCollector; - - void AddEntry(int entry, Object* key, Object* value); - void RemoveEntry(int entry); - - // Returns the index to the value of an entry. - static inline int EntryToValueIndex(int entry) { - return EntryToIndex(entry) + 1; - } -}; - - -// JSFunctionResultCache caches results of some JSFunction invocation. -// It is a fixed array with fixed structure: -// [0]: factory function -// [1]: finger index -// [2]: current cache size -// [3]: dummy field. -// The rest of array are key/value pairs. -class JSFunctionResultCache: public FixedArray { - public: - static const int kFactoryIndex = 0; - static const int kFingerIndex = kFactoryIndex + 1; - static const int kCacheSizeIndex = kFingerIndex + 1; - static const int kDummyIndex = kCacheSizeIndex + 1; - static const int kEntriesIndex = kDummyIndex + 1; - - static const int kEntrySize = 2; // key + value - - static const int kFactoryOffset = kHeaderSize; - static const int kFingerOffset = kFactoryOffset + kPointerSize; - static const int kCacheSizeOffset = kFingerOffset + kPointerSize; - - inline void MakeZeroSize(); - inline void Clear(); - - inline int size(); - inline void set_size(int size); - inline int finger_index(); - inline void set_finger_index(int finger_index); - - // Casting - static inline JSFunctionResultCache* cast(Object* obj); - - DECLARE_VERIFIER(JSFunctionResultCache) -}; - - -// ScopeInfo represents information about different scopes of a source -// program and the allocation of the scope's variables. Scope information -// is stored in a compressed form in ScopeInfo objects and is used -// at runtime (stack dumps, deoptimization, etc.). - -// This object provides quick access to scope info details for runtime -// routines. -class ScopeInfo : public FixedArray { - public: - static inline ScopeInfo* cast(Object* object); - - // Return the type of this scope. - ScopeType Type(); - - // Does this scope call eval? - bool CallsEval(); - - // Return the language mode of this scope. - LanguageMode language_mode(); - - // Is this scope a qml mode scope? - bool IsQmlMode(); - - // Does this scope make a non-strict eval call? - bool CallsNonStrictEval() { - return CallsEval() && (language_mode() == CLASSIC_MODE); - } - - // Return the total number of locals allocated on the stack and in the - // context. This includes the parameters that are allocated in the context. - int LocalCount(); - - // Return the number of stack slots for code. This number consists of two - // parts: - // 1. One stack slot per stack allocated local. - // 2. One stack slot for the function name if it is stack allocated. - int StackSlotCount(); - - // Return the number of context slots for code if a context is allocated. This - // number consists of three parts: - // 1. Size of fixed header for every context: Context::MIN_CONTEXT_SLOTS - // 2. One context slot per context allocated local. - // 3. One context slot for the function name if it is context allocated. - // Parameters allocated in the context count as context allocated locals. If - // no contexts are allocated for this scope ContextLength returns 0. - int ContextLength(bool qml_function = false); - - // Is this scope the scope of a named function expression? - bool HasFunctionName(); - - // Return if this has context allocated locals. - bool HasHeapAllocatedLocals(); - - // Return if contexts are allocated for this scope. - bool HasContext(); - - // Return the function_name if present. - String* FunctionName(); - - // Return the name of the given parameter. - String* ParameterName(int var); - - // Return the name of the given local. - String* LocalName(int var); - - // Return the name of the given stack local. - String* StackLocalName(int var); - - // Return the name of the given context local. - String* ContextLocalName(int var); - - // Return the mode of the given context local. - VariableMode ContextLocalMode(int var); - - // Return the initialization flag of the given context local. - InitializationFlag ContextLocalInitFlag(int var); - - // Lookup support for serialized scope info. Returns the - // the stack slot index for a given slot name if the slot is - // present; otherwise returns a value < 0. The name must be an internalized - // string. - int StackSlotIndex(String* name); - - // Lookup support for serialized scope info. Returns the - // context slot index for a given slot name if the slot is present; otherwise - // returns a value < 0. The name must be an internalized string. - // If the slot is present and mode != NULL, sets *mode to the corresponding - // mode for that variable. - int ContextSlotIndex(String* name, - VariableMode* mode, - InitializationFlag* init_flag); - - // Lookup support for serialized scope info. Returns the - // parameter index for a given parameter name if the parameter is present; - // otherwise returns a value < 0. The name must be an internalized string. - int ParameterIndex(String* name); - - // Lookup support for serialized scope info. Returns the function context - // slot index if the function name is present and context-allocated (named - // function expressions, only), otherwise returns a value < 0. The name - // must be an internalized string. - int FunctionContextSlotIndex(String* name, VariableMode* mode); - - - // Copies all the context locals into an object used to materialize a scope. - bool CopyContextLocalsToScopeObject(Isolate* isolate, - Handle<Context> context, - Handle<JSObject> scope_object); - - - static Handle<ScopeInfo> Create(Scope* scope, Zone* zone); - - // Serializes empty scope info. - static ScopeInfo* Empty(Isolate* isolate); - -#ifdef DEBUG - void Print(); -#endif - - // The layout of the static part of a ScopeInfo is as follows. Each entry is - // numeric and occupies one array slot. - // 1. A set of properties of the scope - // 2. The number of parameters. This only applies to function scopes. For - // non-function scopes this is 0. - // 3. The number of non-parameter variables allocated on the stack. - // 4. The number of non-parameter and parameter variables allocated in the - // context. - // 5. The number of non-parameter and parameter variables allocated in the - // QML context. (technically placeholder) -#define FOR_EACH_NUMERIC_FIELD(V) \ - V(Flags) \ - V(ParameterCount) \ - V(StackLocalCount) \ - V(ContextLocalCount) \ - V(QmlContextLocalCount) - -#define FIELD_ACCESSORS(name) \ - void Set##name(int value) { \ - set(k##name, Smi::FromInt(value)); \ - } \ - int name() { \ - if (length() > 0) { \ - return Smi::cast(get(k##name))->value(); \ - } else { \ - return 0; \ - } \ - } - FOR_EACH_NUMERIC_FIELD(FIELD_ACCESSORS) -#undef FIELD_ACCESSORS - - private: - enum { -#define DECL_INDEX(name) k##name, - FOR_EACH_NUMERIC_FIELD(DECL_INDEX) -#undef DECL_INDEX -#undef FOR_EACH_NUMERIC_FIELD - kVariablePartIndex - }; - - // The layout of the variable part of a ScopeInfo is as follows: - // 1. ParameterEntries: - // This part stores the names of the parameters for function scopes. One - // slot is used per parameter, so in total this part occupies - // ParameterCount() slots in the array. For other scopes than function - // scopes ParameterCount() is 0. - // 2. StackLocalEntries: - // Contains the names of local variables that are allocated on the stack, - // in increasing order of the stack slot index. One slot is used per stack - // local, so in total this part occupies StackLocalCount() slots in the - // array. - // 3. ContextLocalNameEntries: - // Contains the names of local variables and parameters that are allocated - // in the context. They are stored in increasing order of the context slot - // index starting with Context::MIN_CONTEXT_SLOTS. One slot is used per - // context local, so in total this part occupies ContextLocalCount() slots - // in the array. - // 4. ContextLocalInfoEntries: - // Contains the variable modes and initialization flags corresponding to - // the context locals in ContextLocalNameEntries. One slot is used per - // context local, so in total this part occupies ContextLocalCount() - // slots in the array. - // 5. FunctionNameEntryIndex: - // If the scope belongs to a named function expression this part contains - // information about the function variable. It always occupies two array - // slots: a. The name of the function variable. - // b. The context or stack slot index for the variable. - int ParameterEntriesIndex(); - int StackLocalEntriesIndex(); - int ContextLocalNameEntriesIndex(); - int ContextLocalInfoEntriesIndex(); - int FunctionNameEntryIndex(); - - // Location of the function variable for named function expressions. - enum FunctionVariableInfo { - NONE, // No function name present. - STACK, // Function - CONTEXT, - UNUSED - }; - - // Properties of scopes. - class TypeField: public BitField<ScopeType, 0, 3> {}; - class CallsEvalField: public BitField<bool, 3, 1> {}; - class LanguageModeField: public BitField<LanguageMode, 4, 2> {}; - class QmlModeField: public BitField<bool, 6, 1> {}; - class FunctionVariableField: public BitField<FunctionVariableInfo, 7, 2> {}; - class FunctionVariableMode: public BitField<VariableMode, 9, 3> {}; - - // BitFields representing the encoded information for context locals in the - // ContextLocalInfoEntries part. - class ContextLocalMode: public BitField<VariableMode, 0, 3> {}; - class ContextLocalInitFlag: public BitField<InitializationFlag, 3, 1> {}; -}; - - -// The cache for maps used by normalized (dictionary mode) objects. -// Such maps do not have property descriptors, so a typical program -// needs very limited number of distinct normalized maps. -class NormalizedMapCache: public FixedArray { - public: - static const int kEntries = 64; - - MUST_USE_RESULT MaybeObject* Get(JSObject* object, - PropertyNormalizationMode mode); - - void Clear(); - - // Casting - static inline NormalizedMapCache* cast(Object* obj); - - DECLARE_VERIFIER(NormalizedMapCache) -}; - - -// ByteArray represents fixed sized byte arrays. Used for the relocation info -// that is attached to code objects. -class ByteArray: public FixedArrayBase { - public: - inline int Size() { return RoundUp(length() + kHeaderSize, kPointerSize); } - - // Setter and getter. - inline byte get(int index); - inline void set(int index, byte value); - - // Treat contents as an int array. - inline int get_int(int index); - - static int SizeFor(int length) { - return OBJECT_POINTER_ALIGN(kHeaderSize + length); - } - // We use byte arrays for free blocks in the heap. Given a desired size in - // bytes that is a multiple of the word size and big enough to hold a byte - // array, this function returns the number of elements a byte array should - // have. - static int LengthFor(int size_in_bytes) { - ASSERT(IsAligned(size_in_bytes, kPointerSize)); - ASSERT(size_in_bytes >= kHeaderSize); - return size_in_bytes - kHeaderSize; - } - - // Returns data start address. - inline Address GetDataStartAddress(); - - // Returns a pointer to the ByteArray object for a given data start address. - static inline ByteArray* FromDataStartAddress(Address address); - - // Casting. - static inline ByteArray* cast(Object* obj); - - // Dispatched behavior. - inline int ByteArraySize() { - return SizeFor(this->length()); - } - DECLARE_PRINTER(ByteArray) - DECLARE_VERIFIER(ByteArray) - - // Layout description. - static const int kAlignedSize = OBJECT_POINTER_ALIGN(kHeaderSize); - - // Maximal memory consumption for a single ByteArray. - static const int kMaxSize = 512 * MB; - // Maximal length of a single ByteArray. - static const int kMaxLength = kMaxSize - kHeaderSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ByteArray); -}; - - -// FreeSpace represents fixed sized areas of the heap that are not currently in -// use. Used by the heap and GC. -class FreeSpace: public HeapObject { - public: - // [size]: size of the free space including the header. - inline int size(); - inline void set_size(int value); - - inline int Size() { return size(); } - - // Casting. - static inline FreeSpace* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(FreeSpace) - DECLARE_VERIFIER(FreeSpace) - - // Layout description. - // Size is smi tagged when it is stored. - static const int kSizeOffset = HeapObject::kHeaderSize; - static const int kHeaderSize = kSizeOffset + kPointerSize; - - static const int kAlignedSize = OBJECT_POINTER_ALIGN(kHeaderSize); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(FreeSpace); -}; - - -// An ExternalArray represents a fixed-size array of primitive values -// which live outside the JavaScript heap. Its subclasses are used to -// implement the CanvasArray types being defined in the WebGL -// specification. As of this writing the first public draft is not yet -// available, but Khronos members can access the draft at: -// https://cvs.khronos.org/svn/repos/3dweb/trunk/doc/spec/WebGL-spec.html -// -// The semantics of these arrays differ from CanvasPixelArray. -// Out-of-range values passed to the setter are converted via a C -// cast, not clamping. Out-of-range indices cause exceptions to be -// raised rather than being silently ignored. -class ExternalArray: public FixedArrayBase { - public: - inline bool is_the_hole(int index) { return false; } - - // [external_pointer]: The pointer to the external memory area backing this - // external array. - DECL_ACCESSORS(external_pointer, void) // Pointer to the data store. - - // Casting. - static inline ExternalArray* cast(Object* obj); - - // Maximal acceptable length for an external array. - static const int kMaxLength = 0x3fffffff; - - // ExternalArray headers are not quadword aligned. - static const int kExternalPointerOffset = - POINTER_SIZE_ALIGN(FixedArrayBase::kLengthOffset + kPointerSize); - static const int kHeaderSize = kExternalPointerOffset + kPointerSize; - static const int kAlignedSize = OBJECT_POINTER_ALIGN(kHeaderSize); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalArray); -}; - - -// A ExternalPixelArray represents a fixed-size byte array with special -// semantics used for implementing the CanvasPixelArray object. Please see the -// specification at: - -// http://www.whatwg.org/specs/web-apps/current-work/ -// multipage/the-canvas-element.html#canvaspixelarray -// In particular, write access clamps the value written to 0 or 255 if the -// value written is outside this range. -class ExternalPixelArray: public ExternalArray { - public: - inline uint8_t* external_pixel_pointer(); - - // Setter and getter. - inline uint8_t get_scalar(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, uint8_t value); - - // This accessor applies the correct conversion from Smi, HeapNumber and - // undefined and clamps the converted value between 0 and 255. - Object* SetValue(uint32_t index, Object* value); - - // Casting. - static inline ExternalPixelArray* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExternalPixelArray) - DECLARE_VERIFIER(ExternalPixelArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalPixelArray); -}; - - -class ExternalByteArray: public ExternalArray { - public: - // Setter and getter. - inline int8_t get_scalar(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, int8_t value); - - // This accessor applies the correct conversion from Smi, HeapNumber - // and undefined. - MUST_USE_RESULT MaybeObject* SetValue(uint32_t index, Object* value); - - // Casting. - static inline ExternalByteArray* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExternalByteArray) - DECLARE_VERIFIER(ExternalByteArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalByteArray); -}; - - -class ExternalUnsignedByteArray: public ExternalArray { - public: - // Setter and getter. - inline uint8_t get_scalar(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, uint8_t value); - - // This accessor applies the correct conversion from Smi, HeapNumber - // and undefined. - MUST_USE_RESULT MaybeObject* SetValue(uint32_t index, Object* value); - - // Casting. - static inline ExternalUnsignedByteArray* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExternalUnsignedByteArray) - DECLARE_VERIFIER(ExternalUnsignedByteArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalUnsignedByteArray); -}; - - -class ExternalShortArray: public ExternalArray { - public: - // Setter and getter. - inline int16_t get_scalar(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, int16_t value); - - // This accessor applies the correct conversion from Smi, HeapNumber - // and undefined. - MUST_USE_RESULT MaybeObject* SetValue(uint32_t index, Object* value); - - // Casting. - static inline ExternalShortArray* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExternalShortArray) - DECLARE_VERIFIER(ExternalShortArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalShortArray); -}; - - -class ExternalUnsignedShortArray: public ExternalArray { - public: - // Setter and getter. - inline uint16_t get_scalar(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, uint16_t value); - - // This accessor applies the correct conversion from Smi, HeapNumber - // and undefined. - MUST_USE_RESULT MaybeObject* SetValue(uint32_t index, Object* value); - - // Casting. - static inline ExternalUnsignedShortArray* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExternalUnsignedShortArray) - DECLARE_VERIFIER(ExternalUnsignedShortArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalUnsignedShortArray); -}; - - -class ExternalIntArray: public ExternalArray { - public: - // Setter and getter. - inline int32_t get_scalar(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, int32_t value); - - // This accessor applies the correct conversion from Smi, HeapNumber - // and undefined. - MUST_USE_RESULT MaybeObject* SetValue(uint32_t index, Object* value); - - // Casting. - static inline ExternalIntArray* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExternalIntArray) - DECLARE_VERIFIER(ExternalIntArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalIntArray); -}; - - -class ExternalUnsignedIntArray: public ExternalArray { - public: - // Setter and getter. - inline uint32_t get_scalar(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, uint32_t value); - - // This accessor applies the correct conversion from Smi, HeapNumber - // and undefined. - MUST_USE_RESULT MaybeObject* SetValue(uint32_t index, Object* value); - - // Casting. - static inline ExternalUnsignedIntArray* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExternalUnsignedIntArray) - DECLARE_VERIFIER(ExternalUnsignedIntArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalUnsignedIntArray); -}; - - -class ExternalFloatArray: public ExternalArray { - public: - // Setter and getter. - inline float get_scalar(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, float value); - - // This accessor applies the correct conversion from Smi, HeapNumber - // and undefined. - MUST_USE_RESULT MaybeObject* SetValue(uint32_t index, Object* value); - - // Casting. - static inline ExternalFloatArray* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExternalFloatArray) - DECLARE_VERIFIER(ExternalFloatArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalFloatArray); -}; - - -class ExternalDoubleArray: public ExternalArray { - public: - // Setter and getter. - inline double get_scalar(int index); - MUST_USE_RESULT inline MaybeObject* get(int index); - inline void set(int index, double value); - - // This accessor applies the correct conversion from Smi, HeapNumber - // and undefined. - MUST_USE_RESULT MaybeObject* SetValue(uint32_t index, Object* value); - - // Casting. - static inline ExternalDoubleArray* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExternalDoubleArray) - DECLARE_VERIFIER(ExternalDoubleArray) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalDoubleArray); -}; - - -// DeoptimizationInputData is a fixed array used to hold the deoptimization -// data for code generated by the Hydrogen/Lithium compiler. It also -// contains information about functions that were inlined. If N different -// functions were inlined then first N elements of the literal array will -// contain these functions. -// -// It can be empty. -class DeoptimizationInputData: public FixedArray { - public: - // Layout description. Indices in the array. - static const int kTranslationByteArrayIndex = 0; - static const int kInlinedFunctionCountIndex = 1; - static const int kLiteralArrayIndex = 2; - static const int kOsrAstIdIndex = 3; - static const int kOsrPcOffsetIndex = 4; - static const int kFirstDeoptEntryIndex = 5; - - // Offsets of deopt entry elements relative to the start of the entry. - static const int kAstIdRawOffset = 0; - static const int kTranslationIndexOffset = 1; - static const int kArgumentsStackHeightOffset = 2; - static const int kPcOffset = 3; - static const int kDeoptEntrySize = 4; - - // Simple element accessors. -#define DEFINE_ELEMENT_ACCESSORS(name, type) \ - type* name() { \ - return type::cast(get(k##name##Index)); \ - } \ - void Set##name(type* value) { \ - set(k##name##Index, value); \ - } - - DEFINE_ELEMENT_ACCESSORS(TranslationByteArray, ByteArray) - DEFINE_ELEMENT_ACCESSORS(InlinedFunctionCount, Smi) - DEFINE_ELEMENT_ACCESSORS(LiteralArray, FixedArray) - DEFINE_ELEMENT_ACCESSORS(OsrAstId, Smi) - DEFINE_ELEMENT_ACCESSORS(OsrPcOffset, Smi) - -#undef DEFINE_ELEMENT_ACCESSORS - - // Accessors for elements of the ith deoptimization entry. -#define DEFINE_ENTRY_ACCESSORS(name, type) \ - type* name(int i) { \ - return type::cast(get(IndexForEntry(i) + k##name##Offset)); \ - } \ - void Set##name(int i, type* value) { \ - set(IndexForEntry(i) + k##name##Offset, value); \ - } - - DEFINE_ENTRY_ACCESSORS(AstIdRaw, Smi) - DEFINE_ENTRY_ACCESSORS(TranslationIndex, Smi) - DEFINE_ENTRY_ACCESSORS(ArgumentsStackHeight, Smi) - DEFINE_ENTRY_ACCESSORS(Pc, Smi) - -#undef DEFINE_ENTRY_ACCESSORS - - BailoutId AstId(int i) { - return BailoutId(AstIdRaw(i)->value()); - } - - void SetAstId(int i, BailoutId value) { - SetAstIdRaw(i, Smi::FromInt(value.ToInt())); - } - - int DeoptCount() { - return (length() - kFirstDeoptEntryIndex) / kDeoptEntrySize; - } - - // Allocates a DeoptimizationInputData. - MUST_USE_RESULT static MaybeObject* Allocate(int deopt_entry_count, - PretenureFlag pretenure); - - // Casting. - static inline DeoptimizationInputData* cast(Object* obj); - -#ifdef ENABLE_DISASSEMBLER - void DeoptimizationInputDataPrint(FILE* out); -#endif - - private: - static int IndexForEntry(int i) { - return kFirstDeoptEntryIndex + (i * kDeoptEntrySize); - } - - static int LengthFor(int entry_count) { - return IndexForEntry(entry_count); - } -}; - - -// DeoptimizationOutputData is a fixed array used to hold the deoptimization -// data for code generated by the full compiler. -// The format of the these objects is -// [i * 2]: Ast ID for ith deoptimization. -// [i * 2 + 1]: PC and state of ith deoptimization -class DeoptimizationOutputData: public FixedArray { - public: - int DeoptPoints() { return length() / 2; } - - BailoutId AstId(int index) { - return BailoutId(Smi::cast(get(index * 2))->value()); - } - - void SetAstId(int index, BailoutId id) { - set(index * 2, Smi::FromInt(id.ToInt())); - } - - Smi* PcAndState(int index) { return Smi::cast(get(1 + index * 2)); } - void SetPcAndState(int index, Smi* offset) { set(1 + index * 2, offset); } - - static int LengthOfFixedArray(int deopt_points) { - return deopt_points * 2; - } - - // Allocates a DeoptimizationOutputData. - MUST_USE_RESULT static MaybeObject* Allocate(int number_of_deopt_points, - PretenureFlag pretenure); - - // Casting. - static inline DeoptimizationOutputData* cast(Object* obj); - -#if defined(OBJECT_PRINT) || defined(ENABLE_DISASSEMBLER) - void DeoptimizationOutputDataPrint(FILE* out); -#endif -}; - - -// Forward declaration. -class JSGlobalPropertyCell; - -// TypeFeedbackCells is a fixed array used to hold the association between -// cache cells and AST ids for code generated by the full compiler. -// The format of the these objects is -// [i * 2]: Global property cell of ith cache cell. -// [i * 2 + 1]: Ast ID for ith cache cell. -class TypeFeedbackCells: public FixedArray { - public: - int CellCount() { return length() / 2; } - static int LengthOfFixedArray(int cell_count) { return cell_count * 2; } - - // Accessors for AST ids associated with cache values. - inline TypeFeedbackId AstId(int index); - inline void SetAstId(int index, TypeFeedbackId id); - - // Accessors for global property cells holding the cache values. - inline JSGlobalPropertyCell* Cell(int index); - inline void SetCell(int index, JSGlobalPropertyCell* cell); - - // The object that indicates an uninitialized cache. - static inline Handle<Object> UninitializedSentinel(Isolate* isolate); - - // The object that indicates a megamorphic state. - static inline Handle<Object> MegamorphicSentinel(Isolate* isolate); - - // The object that indicates a monomorphic state of Array with - // ElementsKind - static inline Handle<Object> MonomorphicArraySentinel(Isolate* isolate, - ElementsKind elements_kind); - - // A raw version of the uninitialized sentinel that's safe to read during - // garbage collection (e.g., for patching the cache). - static inline Object* RawUninitializedSentinel(Heap* heap); - - // Casting. - static inline TypeFeedbackCells* cast(Object* obj); - - static const int kForInFastCaseMarker = 0; - static const int kForInSlowCaseMarker = 1; -}; - - -// Forward declaration. -class SafepointEntry; -class TypeFeedbackInfo; - -// Code describes objects with on-the-fly generated machine code. -class Code: public HeapObject { - public: - // Opaque data type for encapsulating code flags like kind, inline - // cache state, and arguments count. - // FLAGS_MIN_VALUE and FLAGS_MAX_VALUE are specified to ensure that - // enumeration type has correct value range (see Issue 830 for more details). - enum Flags { - FLAGS_MIN_VALUE = kMinInt, - FLAGS_MAX_VALUE = kMaxInt - }; - -#define CODE_KIND_LIST(V) \ - V(FUNCTION) \ - V(OPTIMIZED_FUNCTION) \ - V(STUB) \ - V(COMPILED_STUB) \ - V(BUILTIN) \ - V(LOAD_IC) \ - V(KEYED_LOAD_IC) \ - V(CALL_IC) \ - V(KEYED_CALL_IC) \ - V(STORE_IC) \ - V(KEYED_STORE_IC) \ - V(UNARY_OP_IC) \ - V(BINARY_OP_IC) \ - V(COMPARE_IC) \ - V(TO_BOOLEAN_IC) - - enum Kind { -#define DEFINE_CODE_KIND_ENUM(name) name, - CODE_KIND_LIST(DEFINE_CODE_KIND_ENUM) -#undef DEFINE_CODE_KIND_ENUM - - // Pseudo-kinds. - LAST_CODE_KIND = TO_BOOLEAN_IC, - REGEXP = BUILTIN, - FIRST_IC_KIND = LOAD_IC, - LAST_IC_KIND = TO_BOOLEAN_IC - }; - - // No more than 16 kinds. The value is currently encoded in four bits in - // Flags. - STATIC_ASSERT(LAST_CODE_KIND < 16); - - static const char* Kind2String(Kind kind); - - // Types of stubs. - enum StubType { - NORMAL, - FIELD, - CONSTANT_FUNCTION, - CALLBACKS, - INTERCEPTOR, - MAP_TRANSITION, - NONEXISTENT - }; - - enum IcFragment { - IC_FRAGMENT, - HANDLER_FRAGMENT - }; - - enum { - NUMBER_OF_KINDS = LAST_IC_KIND + 1 - }; - - typedef int ExtraICState; - - static const ExtraICState kNoExtraICState = 0; - -#ifdef ENABLE_DISASSEMBLER - // Printing - static const char* ICState2String(InlineCacheState state); - static const char* StubType2String(StubType type); - static void PrintExtraICState(FILE* out, Kind kind, ExtraICState extra); - inline void Disassemble(const char* name) { - Disassemble(name, stdout); - } - void Disassemble(const char* name, FILE* out); -#endif // ENABLE_DISASSEMBLER - - // [instruction_size]: Size of the native instructions - inline int instruction_size(); - inline void set_instruction_size(int value); - - // [relocation_info]: Code relocation information - DECL_ACCESSORS(relocation_info, ByteArray) - void InvalidateRelocation(); - - // [handler_table]: Fixed array containing offsets of exception handlers. - DECL_ACCESSORS(handler_table, FixedArray) - - // [deoptimization_data]: Array containing data for deopt. - DECL_ACCESSORS(deoptimization_data, FixedArray) - - // [type_feedback_info]: Struct containing type feedback information for - // unoptimized code. Optimized code can temporarily store the head of - // the list of the dependent optimized functions during deoptimization. - // STUBs can use this slot to store arbitrary information as a Smi. - // Will contain either a TypeFeedbackInfo object, or JSFunction object, - // or undefined, or a Smi. - DECL_ACCESSORS(type_feedback_info, Object) - inline void InitializeTypeFeedbackInfoNoWriteBarrier(Object* value); - inline int stub_info(); - inline void set_stub_info(int info); - inline Object* deoptimizing_functions(); - inline void set_deoptimizing_functions(Object* value); - - // [gc_metadata]: Field used to hold GC related metadata. The contents of this - // field does not have to be traced during garbage collection since - // it is only used by the garbage collector itself. - DECL_ACCESSORS(gc_metadata, Object) - - // [ic_age]: Inline caching age: the value of the Heap::global_ic_age - // at the moment when this object was created. - inline void set_ic_age(int count); - inline int ic_age(); - - // [prologue_offset]: Offset of the function prologue, used for aging - // FUNCTIONs and OPTIMIZED_FUNCTIONs. - inline int prologue_offset(); - inline void set_prologue_offset(int offset); - - // Unchecked accessors to be used during GC. - inline ByteArray* unchecked_relocation_info(); - inline FixedArray* unchecked_deoptimization_data(); - - inline int relocation_size(); - - // [flags]: Various code flags. - inline Flags flags(); - inline void set_flags(Flags flags); - - // [flags]: Access to specific code flags. - inline Kind kind(); - inline InlineCacheState ic_state(); // Only valid for IC stubs. - inline ExtraICState extra_ic_state(); // Only valid for IC stubs. - inline StubType type(); // Only valid for monomorphic IC stubs. - inline int arguments_count(); // Only valid for call IC stubs. - - // Testers for IC stub kinds. - inline bool is_inline_cache_stub(); - inline bool is_debug_break(); - inline bool is_load_stub() { return kind() == LOAD_IC; } - inline bool is_keyed_load_stub() { return kind() == KEYED_LOAD_IC; } - inline bool is_store_stub() { return kind() == STORE_IC; } - inline bool is_keyed_store_stub() { return kind() == KEYED_STORE_IC; } - inline bool is_call_stub() { return kind() == CALL_IC; } - inline bool is_keyed_call_stub() { return kind() == KEYED_CALL_IC; } - inline bool is_unary_op_stub() { return kind() == UNARY_OP_IC; } - inline bool is_binary_op_stub() { return kind() == BINARY_OP_IC; } - inline bool is_compare_ic_stub() { return kind() == COMPARE_IC; } - inline bool is_to_boolean_ic_stub() { return kind() == TO_BOOLEAN_IC; } - - // [major_key]: For kind STUB or BINARY_OP_IC, the major key. - inline int major_key(); - inline void set_major_key(int value); - - // For stubs, tells whether they should always exist, so that they can be - // called from other stubs. - inline bool is_pregenerated(); - inline void set_is_pregenerated(bool value); - - // [optimizable]: For FUNCTION kind, tells if it is optimizable. - inline bool optimizable(); - inline void set_optimizable(bool value); - - // [has_deoptimization_support]: For FUNCTION kind, tells if it has - // deoptimization support. - inline bool has_deoptimization_support(); - inline void set_has_deoptimization_support(bool value); - - // [has_debug_break_slots]: For FUNCTION kind, tells if it has - // been compiled with debug break slots. - inline bool has_debug_break_slots(); - inline void set_has_debug_break_slots(bool value); - - // [compiled_with_optimizing]: For FUNCTION kind, tells if it has - // been compiled with IsOptimizing set to true. - inline bool is_compiled_optimizable(); - inline void set_compiled_optimizable(bool value); - - // [allow_osr_at_loop_nesting_level]: For FUNCTION kind, tells for - // how long the function has been marked for OSR and therefore which - // level of loop nesting we are willing to do on-stack replacement - // for. - inline void set_allow_osr_at_loop_nesting_level(int level); - inline int allow_osr_at_loop_nesting_level(); - - // [profiler_ticks]: For FUNCTION kind, tells for how many profiler ticks - // the code object was seen on the stack with no IC patching going on. - inline int profiler_ticks(); - inline void set_profiler_ticks(int ticks); - - // [stack_slots]: For kind OPTIMIZED_FUNCTION, the number of stack slots - // reserved in the code prologue. - inline unsigned stack_slots(); - inline void set_stack_slots(unsigned slots); - - // [safepoint_table_start]: For kind OPTIMIZED_CODE, the offset in - // the instruction stream where the safepoint table starts. - inline unsigned safepoint_table_offset(); - inline void set_safepoint_table_offset(unsigned offset); - - // [stack_check_table_start]: For kind FUNCTION, the offset in the - // instruction stream where the stack check table starts. - inline unsigned stack_check_table_offset(); - inline void set_stack_check_table_offset(unsigned offset); - - // [check type]: For kind CALL_IC, tells how to check if the - // receiver is valid for the given call. - inline CheckType check_type(); - inline void set_check_type(CheckType value); - - // [type-recording unary op type]: For kind UNARY_OP_IC. - inline byte unary_op_type(); - inline void set_unary_op_type(byte value); - - // [to_boolean_foo]: For kind TO_BOOLEAN_IC tells what state the stub is in. - inline byte to_boolean_state(); - inline void set_to_boolean_state(byte value); - - // [has_function_cache]: For kind STUB tells whether there is a function - // cache is passed to the stub. - inline bool has_function_cache(); - inline void set_has_function_cache(bool flag); - - - // [marked_for_deoptimization]: For kind OPTIMIZED_FUNCTION tells whether - // the code is going to be deoptimized because of dead embedded maps. - inline bool marked_for_deoptimization(); - inline void set_marked_for_deoptimization(bool flag); - - bool allowed_in_shared_map_code_cache(); - - // Get the safepoint entry for the given pc. - SafepointEntry GetSafepointEntry(Address pc); - - // Mark this code object as not having a stack check table. Assumes kind - // is FUNCTION. - void SetNoStackCheckTable(); - - // Find the first map in an IC stub. - Map* FindFirstMap(); - void FindAllMaps(MapHandleList* maps); - - // Find the first code in an IC stub. - Code* FindFirstCode(); - void FindAllCode(CodeHandleList* code_list, int length); - - class ExtraICStateStrictMode: public BitField<StrictModeFlag, 0, 1> {}; - class ExtraICStateKeyedAccessGrowMode: - public BitField<KeyedAccessGrowMode, 1, 1> {}; // NOLINT - - static const int kExtraICStateGrowModeShift = 1; - - static inline StrictModeFlag GetStrictMode(ExtraICState extra_ic_state) { - return ExtraICStateStrictMode::decode(extra_ic_state); - } - - static inline KeyedAccessGrowMode GetKeyedAccessGrowMode( - ExtraICState extra_ic_state) { - return ExtraICStateKeyedAccessGrowMode::decode(extra_ic_state); - } - - static inline ExtraICState ComputeExtraICState( - KeyedAccessGrowMode grow_mode, - StrictModeFlag strict_mode) { - return ExtraICStateKeyedAccessGrowMode::encode(grow_mode) | - ExtraICStateStrictMode::encode(strict_mode); - } - - // Flags operations. - static inline Flags ComputeFlags( - Kind kind, - InlineCacheState ic_state = UNINITIALIZED, - ExtraICState extra_ic_state = kNoExtraICState, - StubType type = NORMAL, - int argc = -1, - InlineCacheHolderFlag holder = OWN_MAP); - - static inline Flags ComputeMonomorphicFlags( - Kind kind, - ExtraICState extra_ic_state = kNoExtraICState, - StubType type = NORMAL, - int argc = -1, - InlineCacheHolderFlag holder = OWN_MAP); - - static inline InlineCacheState ExtractICStateFromFlags(Flags flags); - static inline StubType ExtractTypeFromFlags(Flags flags); - static inline Kind ExtractKindFromFlags(Flags flags); - static inline InlineCacheHolderFlag ExtractCacheHolderFromFlags(Flags flags); - static inline ExtraICState ExtractExtraICStateFromFlags(Flags flags); - static inline int ExtractArgumentsCountFromFlags(Flags flags); - - static inline Flags RemoveTypeFromFlags(Flags flags); - - // Convert a target address into a code object. - static inline Code* GetCodeFromTargetAddress(Address address); - - // Convert an entry address into an object. - static inline Object* GetObjectFromEntryAddress(Address location_of_address); - - // Returns the address of the first instruction. - inline byte* instruction_start(); - - // Returns the address right after the last instruction. - inline byte* instruction_end(); - - // Returns the size of the instructions, padding, and relocation information. - inline int body_size(); - - // Returns the address of the first relocation info (read backwards!). - inline byte* relocation_start(); - - // Code entry point. - inline byte* entry(); - - // Returns true if pc is inside this object's instructions. - inline bool contains(byte* pc); - - // Relocate the code by delta bytes. Called to signal that this code - // object has been moved by delta bytes. - void Relocate(intptr_t delta); - - // Migrate code described by desc. - void CopyFrom(const CodeDesc& desc); - - // Returns the object size for a given body (used for allocation). - static int SizeFor(int body_size) { - ASSERT_SIZE_TAG_ALIGNED(body_size); - return RoundUp(kHeaderSize + body_size, kCodeAlignment); - } - - // Calculate the size of the code object to report for log events. This takes - // the layout of the code object into account. - int ExecutableSize() { - // Check that the assumptions about the layout of the code object holds. - ASSERT_EQ(static_cast<int>(instruction_start() - address()), - Code::kHeaderSize); - return instruction_size() + Code::kHeaderSize; - } - - // Locating source position. - int SourcePosition(Address pc); - int SourceStatementPosition(Address pc); - - // Casting. - static inline Code* cast(Object* obj); - - // Dispatched behavior. - int CodeSize() { return SizeFor(body_size()); } - inline void CodeIterateBody(ObjectVisitor* v); - - template<typename StaticVisitor> - inline void CodeIterateBody(Heap* heap); - - DECLARE_PRINTER(Code) - DECLARE_VERIFIER(Code) - - void ClearInlineCaches(); - void ClearTypeFeedbackCells(Heap* heap); - -#define DECLARE_CODE_AGE_ENUM(X) k##X##CodeAge, - enum Age { - kNoAge = 0, - CODE_AGE_LIST(DECLARE_CODE_AGE_ENUM) - kAfterLastCodeAge, - kLastCodeAge = kAfterLastCodeAge - 1, - kCodeAgeCount = kAfterLastCodeAge - 1 - }; -#undef DECLARE_CODE_AGE_ENUM - - // Code aging - static void MakeCodeAgeSequenceYoung(byte* sequence); - void MakeOlder(MarkingParity); - static bool IsYoungSequence(byte* sequence); - bool IsOld(); - - void PrintDeoptLocation(int bailout_id); - -#ifdef VERIFY_HEAP - void VerifyEmbeddedMapsDependency(); -#endif - - // Max loop nesting marker used to postpose OSR. We don't take loop - // nesting that is deeper than 5 levels into account. - static const int kMaxLoopNestingMarker = 6; - - // Layout description. - static const int kInstructionSizeOffset = HeapObject::kHeaderSize; - static const int kRelocationInfoOffset = kInstructionSizeOffset + kIntSize; - static const int kHandlerTableOffset = kRelocationInfoOffset + kPointerSize; - static const int kDeoptimizationDataOffset = - kHandlerTableOffset + kPointerSize; - static const int kTypeFeedbackInfoOffset = - kDeoptimizationDataOffset + kPointerSize; - static const int kGCMetadataOffset = kTypeFeedbackInfoOffset + kPointerSize; - static const int kICAgeOffset = - kGCMetadataOffset + kPointerSize; - static const int kFlagsOffset = kICAgeOffset + kIntSize; - static const int kKindSpecificFlags1Offset = kFlagsOffset + kIntSize; - static const int kKindSpecificFlags2Offset = - kKindSpecificFlags1Offset + kIntSize; - // Note: We might be able to squeeze this into the flags above. - static const int kPrologueOffset = kKindSpecificFlags2Offset + kIntSize; - - static const int kHeaderPaddingStart = kPrologueOffset + kIntSize; - - // Add padding to align the instruction start following right after - // the Code object header. - static const int kHeaderSize = - (kHeaderPaddingStart + kCodeAlignmentMask) & ~kCodeAlignmentMask; - - // Byte offsets within kKindSpecificFlags1Offset. - static const int kOptimizableOffset = kKindSpecificFlags1Offset; - static const int kCheckTypeOffset = kKindSpecificFlags1Offset; - - static const int kFullCodeFlags = kOptimizableOffset + 1; - class FullCodeFlagsHasDeoptimizationSupportField: - public BitField<bool, 0, 1> {}; // NOLINT - class FullCodeFlagsHasDebugBreakSlotsField: public BitField<bool, 1, 1> {}; - class FullCodeFlagsIsCompiledOptimizable: public BitField<bool, 2, 1> {}; - - static const int kAllowOSRAtLoopNestingLevelOffset = kFullCodeFlags + 1; - static const int kProfilerTicksOffset = kAllowOSRAtLoopNestingLevelOffset + 1; - - // Flags layout. BitField<type, shift, size>. - class ICStateField: public BitField<InlineCacheState, 0, 3> {}; - class TypeField: public BitField<StubType, 3, 3> {}; - class CacheHolderField: public BitField<InlineCacheHolderFlag, 6, 1> {}; - class KindField: public BitField<Kind, 7, 4> {}; - class ExtraICStateField: public BitField<ExtraICState, 11, 2> {}; - class IsPregeneratedField: public BitField<bool, 13, 1> {}; - - // KindSpecificFlags1 layout (STUB and OPTIMIZED_FUNCTION) - static const int kStackSlotsFirstBit = 0; - static const int kStackSlotsBitCount = 24; - static const int kUnaryOpTypeFirstBit = - kStackSlotsFirstBit + kStackSlotsBitCount; - static const int kUnaryOpTypeBitCount = 3; - static const int kToBooleanStateFirstBit = - kStackSlotsFirstBit + kStackSlotsBitCount; - static const int kToBooleanStateBitCount = 8; - static const int kHasFunctionCacheFirstBit = - kStackSlotsFirstBit + kStackSlotsBitCount; - static const int kHasFunctionCacheBitCount = 1; - static const int kMarkedForDeoptimizationFirstBit = - kStackSlotsFirstBit + kStackSlotsBitCount + 1; - static const int kMarkedForDeoptimizationBitCount = 1; - - STATIC_ASSERT(kStackSlotsFirstBit + kStackSlotsBitCount <= 32); - STATIC_ASSERT(kUnaryOpTypeFirstBit + kUnaryOpTypeBitCount <= 32); - STATIC_ASSERT(kToBooleanStateFirstBit + kToBooleanStateBitCount <= 32); - STATIC_ASSERT(kHasFunctionCacheFirstBit + kHasFunctionCacheBitCount <= 32); - STATIC_ASSERT(kMarkedForDeoptimizationFirstBit + - kMarkedForDeoptimizationBitCount <= 32); - - class StackSlotsField: public BitField<int, - kStackSlotsFirstBit, kStackSlotsBitCount> {}; // NOLINT - class UnaryOpTypeField: public BitField<int, - kUnaryOpTypeFirstBit, kUnaryOpTypeBitCount> {}; // NOLINT - class ToBooleanStateField: public BitField<int, - kToBooleanStateFirstBit, kToBooleanStateBitCount> {}; // NOLINT - class HasFunctionCacheField: public BitField<bool, - kHasFunctionCacheFirstBit, kHasFunctionCacheBitCount> {}; // NOLINT - class MarkedForDeoptimizationField: public BitField<bool, - kMarkedForDeoptimizationFirstBit, - kMarkedForDeoptimizationBitCount> {}; // NOLINT - - // KindSpecificFlags2 layout (STUB and OPTIMIZED_FUNCTION) - static const int kStubMajorKeyFirstBit = 0; - static const int kSafepointTableOffsetFirstBit = - kStubMajorKeyFirstBit + kStubMajorKeyBits; - static const int kSafepointTableOffsetBitCount = 26; - - STATIC_ASSERT(kStubMajorKeyFirstBit + kStubMajorKeyBits <= 32); - STATIC_ASSERT(kSafepointTableOffsetFirstBit + - kSafepointTableOffsetBitCount <= 32); - - class SafepointTableOffsetField: public BitField<int, - kSafepointTableOffsetFirstBit, - kSafepointTableOffsetBitCount> {}; // NOLINT - class StubMajorKeyField: public BitField<int, - kStubMajorKeyFirstBit, kStubMajorKeyBits> {}; // NOLINT - - // KindSpecificFlags2 layout (FUNCTION) - class StackCheckTableOffsetField: public BitField<int, 0, 31> {}; - - // Signed field cannot be encoded using the BitField class. - static const int kArgumentsCountShift = 14; - static const int kArgumentsCountMask = ~((1 << kArgumentsCountShift) - 1); - - // This constant should be encodable in an ARM instruction. - static const int kFlagsNotUsedInLookup = - TypeField::kMask | CacheHolderField::kMask; - - private: - friend class RelocIterator; - - // Code aging - byte* FindCodeAgeSequence(); - static void GetCodeAgeAndParity(Code* code, Age* age, - MarkingParity* parity); - static void GetCodeAgeAndParity(byte* sequence, Age* age, - MarkingParity* parity); - static Code* GetCodeAgeStub(Age age, MarkingParity parity); - - // Code aging -- platform-specific - static void PatchPlatformCodeAge(byte* sequence, Age age, - MarkingParity parity); - - DISALLOW_IMPLICIT_CONSTRUCTORS(Code); -}; - - -// This class describes the layout of dependent codes array of a map. The -// array is partitioned into several groups of dependent codes. Each group -// contains codes with the same dependency on the map. The array has the -// following layout for n dependency groups: -// -// +----+----+-----+----+---------+----------+-----+---------+-----------+ -// | C1 | C2 | ... | Cn | group 1 | group 2 | ... | group n | undefined | -// +----+----+-----+----+---------+----------+-----+---------+-----------+ -// -// The first n elements are Smis, each of them specifies the number of codes -// in the corresponding group. The subsequent elements contain grouped code -// objects. The suffix of the array can be filled with the undefined value if -// the number of codes is less than the length of the array. The order of the -// code objects within a group is not preserved. -// -// All code indexes used in the class are counted starting from the first -// code object of the first group. In other words, code index 0 corresponds -// to array index n = kCodesStartIndex. - -class DependentCode: public FixedArray { - public: - enum DependencyGroup { - // Group of code that weakly embed this map and depend on being - // deoptimized when the map is garbage collected. - kWeaklyEmbeddedGroup, - // Group of code that omit run-time prototype checks for prototypes - // described by this map. The group is deoptimized whenever an object - // described by this map changes shape (and transitions to a new map), - // possibly invalidating the assumptions embedded in the code. - kPrototypeCheckGroup, - kGroupCount = kPrototypeCheckGroup + 1 - }; - - // Array for holding the index of the first code object of each group. - // The last element stores the total number of code objects. - class GroupStartIndexes { - public: - explicit GroupStartIndexes(DependentCode* entries); - void Recompute(DependentCode* entries); - int at(int i) { return start_indexes_[i]; } - int number_of_entries() { return start_indexes_[kGroupCount]; } - private: - int start_indexes_[kGroupCount + 1]; - }; - - bool Contains(DependencyGroup group, Code* code); - static Handle<DependentCode> Insert(Handle<DependentCode> entries, - DependencyGroup group, - Handle<Code> value); - void DeoptimizeDependentCodeGroup(DependentCode::DependencyGroup group); - - // The following low-level accessors should only be used by this class - // and the mark compact collector. - inline int number_of_entries(DependencyGroup group); - inline void set_number_of_entries(DependencyGroup group, int value); - inline Code* code_at(int i); - inline void set_code_at(int i, Code* value); - inline Object** code_slot_at(int i); - inline void clear_code_at(int i); - static inline DependentCode* cast(Object* object); - - private: - // Make a room at the end of the given group by moving out the first - // code objects of the subsequent groups. - inline void ExtendGroup(DependencyGroup group); - static const int kCodesStartIndex = kGroupCount; -}; - - -// All heap objects have a Map that describes their structure. -// A Map contains information about: -// - Size information about the object -// - How to iterate over an object (for garbage collection) -class Map: public HeapObject { - public: - // Instance size. - // Size in bytes or kVariableSizeSentinel if instances do not have - // a fixed size. - inline int instance_size(); - inline void set_instance_size(int value); - - // Count of properties allocated in the object. - inline int inobject_properties(); - inline void set_inobject_properties(int value); - - // Count of property fields pre-allocated in the object when first allocated. - inline int pre_allocated_property_fields(); - inline void set_pre_allocated_property_fields(int value); - - // Instance type. - inline InstanceType instance_type(); - inline void set_instance_type(InstanceType value); - - // Tells how many unused property fields are available in the - // instance (only used for JSObject in fast mode). - inline int unused_property_fields(); - inline void set_unused_property_fields(int value); - - // Bit field. - inline byte bit_field(); - inline void set_bit_field(byte value); - - // Bit field 2. - inline byte bit_field2(); - inline void set_bit_field2(byte value); - - // Bit field 3. - inline int bit_field3(); - inline void set_bit_field3(int value); - - class EnumLengthBits: public BitField<int, 0, 11> {}; - class NumberOfOwnDescriptorsBits: public BitField<int, 11, 11> {}; - class IsShared: public BitField<bool, 22, 1> {}; - class FunctionWithPrototype: public BitField<bool, 23, 1> {}; - class DictionaryMap: public BitField<bool, 24, 1> {}; - class OwnsDescriptors: public BitField<bool, 25, 1> {}; - class IsObserved: public BitField<bool, 26, 1> {}; - class NamedInterceptorIsFallback: public BitField<bool, 27, 1> {}; - class HasInstanceCallHandler: public BitField<bool, 28, 1> {}; - class AttachedToSharedFunctionInfo: public BitField<bool, 29, 1> {}; - - // Tells whether the object in the prototype property will be used - // for instances created from this function. If the prototype - // property is set to a value that is not a JSObject, the prototype - // property will not be used to create instances of the function. - // See ECMA-262, 13.2.2. - inline void set_non_instance_prototype(bool value); - inline bool has_non_instance_prototype(); - - // Tells whether function has special prototype property. If not, prototype - // property will not be created when accessed (will return undefined), - // and construction from this function will not be allowed. - inline void set_function_with_prototype(bool value); - inline bool function_with_prototype(); - - // Tells whether the instance with this map should be ignored by the - // __proto__ accessor. - inline void set_is_hidden_prototype() { - set_bit_field(bit_field() | (1 << kIsHiddenPrototype)); - } - - inline bool is_hidden_prototype() { - return ((1 << kIsHiddenPrototype) & bit_field()) != 0; - } - - // Records and queries whether the instance has a named interceptor. - inline void set_has_named_interceptor() { - set_bit_field(bit_field() | (1 << kHasNamedInterceptor)); - } - - inline bool has_named_interceptor() { - return ((1 << kHasNamedInterceptor) & bit_field()) != 0; - } - - // Records and queries whether the instance has an indexed interceptor. - inline void set_has_indexed_interceptor() { - set_bit_field(bit_field() | (1 << kHasIndexedInterceptor)); - } - - inline bool has_indexed_interceptor() { - return ((1 << kHasIndexedInterceptor) & bit_field()) != 0; - } - - // Tells whether the instance is undetectable. - // An undetectable object is a special class of JSObject: 'typeof' operator - // returns undefined, ToBoolean returns false. Otherwise it behaves like - // a normal JS object. It is useful for implementing undetectable - // document.all in Firefox & Safari. - // See https://bugzilla.mozilla.org/show_bug.cgi?id=248549. - inline void set_is_undetectable() { - set_bit_field(bit_field() | (1 << kIsUndetectable)); - } - - inline bool is_undetectable() { - return ((1 << kIsUndetectable) & bit_field()) != 0; - } - - // Tells whether the instance has a call-as-function handler. - inline void set_has_instance_call_handler() { - set_bit_field3(HasInstanceCallHandler::update(bit_field3(), true)); - } - - inline bool has_instance_call_handler() { - return HasInstanceCallHandler::decode(bit_field3()); - } - - inline void set_is_extensible(bool value); - inline bool is_extensible(); - - inline void set_elements_kind(ElementsKind elements_kind) { - ASSERT(elements_kind < kElementsKindCount); - ASSERT(kElementsKindCount <= (1 << kElementsKindBitCount)); - ASSERT(!is_observed() || - elements_kind == DICTIONARY_ELEMENTS || - elements_kind == NON_STRICT_ARGUMENTS_ELEMENTS || - IsExternalArrayElementsKind(elements_kind)); - set_bit_field2((bit_field2() & ~kElementsKindMask) | - (elements_kind << kElementsKindShift)); - ASSERT(this->elements_kind() == elements_kind); - } - - inline ElementsKind elements_kind() { - return static_cast<ElementsKind>( - (bit_field2() & kElementsKindMask) >> kElementsKindShift); - } - - // Tells whether the instance has fast elements that are only Smis. - inline bool has_fast_smi_elements() { - return IsFastSmiElementsKind(elements_kind()); - } - - // Tells whether the instance has fast elements. - inline bool has_fast_object_elements() { - return IsFastObjectElementsKind(elements_kind()); - } - - inline bool has_fast_smi_or_object_elements() { - return IsFastSmiOrObjectElementsKind(elements_kind()); - } - - inline bool has_fast_double_elements() { - return IsFastDoubleElementsKind(elements_kind()); - } - - inline bool has_fast_elements() { - return IsFastElementsKind(elements_kind()); - } - - inline bool has_non_strict_arguments_elements() { - return elements_kind() == NON_STRICT_ARGUMENTS_ELEMENTS; - } - - inline bool has_external_array_elements() { - return IsExternalArrayElementsKind(elements_kind()); - } - - inline bool has_dictionary_elements() { - return IsDictionaryElementsKind(elements_kind()); - } - - inline bool has_slow_elements_kind() { - return elements_kind() == DICTIONARY_ELEMENTS - || elements_kind() == NON_STRICT_ARGUMENTS_ELEMENTS; - } - - static bool IsValidElementsTransition(ElementsKind from_kind, - ElementsKind to_kind); - - inline bool HasTransitionArray(); - inline bool HasElementsTransition(); - inline Map* elements_transition_map(); - MUST_USE_RESULT inline MaybeObject* set_elements_transition_map( - Map* transitioned_map); - inline void SetTransition(int transition_index, Map* target); - inline Map* GetTransition(int transition_index); - MUST_USE_RESULT inline MaybeObject* AddTransition(String* key, - Map* target, - SimpleTransitionFlag flag); - DECL_ACCESSORS(transitions, TransitionArray) - inline void ClearTransitions(Heap* heap, - WriteBarrierMode mode = UPDATE_WRITE_BARRIER); - - // Tells whether the map is attached to SharedFunctionInfo - // (for inobject slack tracking). - inline void set_attached_to_shared_function_info(bool value); - - inline bool attached_to_shared_function_info(); - - // Tells whether the map is shared between objects that may have different - // behavior. If true, the map should never be modified, instead a clone - // should be created and modified. - inline void set_is_shared(bool value); - inline bool is_shared(); - - // Tells whether the map is used for JSObjects in dictionary mode (ie - // normalized objects, ie objects for which HasFastProperties returns false). - // A map can never be used for both dictionary mode and fast mode JSObjects. - // False by default and for HeapObjects that are not JSObjects. - inline void set_dictionary_map(bool value); - inline bool is_dictionary_map(); - - // Tells whether the instance needs security checks when accessing its - // properties. - inline void set_is_access_check_needed(bool access_check_needed); - inline bool is_access_check_needed(); - - // Whether the named interceptor is a fallback interceptor or not - inline void set_named_interceptor_is_fallback(bool value); - inline bool named_interceptor_is_fallback(); - - // Tells whether the instance has the space for an external resource - // object - inline void set_has_external_resource(bool value); - inline bool has_external_resource(); - - // Tells whether the user object comparison callback should be used for - // comparisons involving this object - inline void set_use_user_object_comparison(bool value); - inline bool use_user_object_comparison(); - - // [prototype]: implicit prototype object. - DECL_ACCESSORS(prototype, Object) - - // [constructor]: points back to the function responsible for this map. - DECL_ACCESSORS(constructor, Object) - - inline JSFunction* unchecked_constructor(); - - // [instance descriptors]: describes the object. - DECL_ACCESSORS(instance_descriptors, DescriptorArray) - inline void InitializeDescriptors(DescriptorArray* descriptors); - - // [stub cache]: contains stubs compiled for this map. - DECL_ACCESSORS(code_cache, Object) - - // [dependent code]: list of optimized codes that have this map embedded. - DECL_ACCESSORS(dependent_code, DependentCode) - - // [back pointer]: points back to the parent map from which a transition - // leads to this map. The field overlaps with prototype transitions and the - // back pointer will be moved into the prototype transitions array if - // required. - inline Object* GetBackPointer(); - inline void SetBackPointer(Object* value, - WriteBarrierMode mode = UPDATE_WRITE_BARRIER); - inline void init_back_pointer(Object* undefined); - - // [prototype transitions]: cache of prototype transitions. - // Prototype transition is a transition that happens - // when we change object's prototype to a new one. - // Cache format: - // 0: finger - index of the first free cell in the cache - // 1: back pointer that overlaps with prototype transitions field. - // 2 + 2 * i: prototype - // 3 + 2 * i: target map - inline FixedArray* GetPrototypeTransitions(); - MUST_USE_RESULT inline MaybeObject* SetPrototypeTransitions( - FixedArray* prototype_transitions); - inline bool HasPrototypeTransitions(); - - inline HeapObject* UncheckedPrototypeTransitions(); - inline TransitionArray* unchecked_transition_array(); - - static const int kProtoTransitionHeaderSize = 1; - static const int kProtoTransitionNumberOfEntriesOffset = 0; - static const int kProtoTransitionElementsPerEntry = 2; - static const int kProtoTransitionPrototypeOffset = 0; - static const int kProtoTransitionMapOffset = 1; - - inline int NumberOfProtoTransitions() { - FixedArray* cache = GetPrototypeTransitions(); - if (cache->length() == 0) return 0; - return - Smi::cast(cache->get(kProtoTransitionNumberOfEntriesOffset))->value(); - } - - inline void SetNumberOfProtoTransitions(int value) { - FixedArray* cache = GetPrototypeTransitions(); - ASSERT(cache->length() != 0); - cache->set_unchecked(kProtoTransitionNumberOfEntriesOffset, - Smi::FromInt(value)); - } - - // Lookup in the map's instance descriptors and fill out the result - // with the given holder if the name is found. The holder may be - // NULL when this function is used from the compiler. - inline void LookupDescriptor(JSObject* holder, - String* name, - LookupResult* result); - - inline void LookupTransition(JSObject* holder, - String* name, - LookupResult* result); - - // The size of transition arrays are limited so they do not end up in large - // object space. Otherwise ClearNonLiveTransitions would leak memory while - // applying in-place right trimming. - inline bool CanHaveMoreTransitions(); - - int LastAdded() { - int number_of_own_descriptors = NumberOfOwnDescriptors(); - ASSERT(number_of_own_descriptors > 0); - return number_of_own_descriptors - 1; - } - - int NumberOfOwnDescriptors() { - return NumberOfOwnDescriptorsBits::decode(bit_field3()); - } - - void SetNumberOfOwnDescriptors(int number) { - ASSERT(number <= instance_descriptors()->number_of_descriptors()); - set_bit_field3(NumberOfOwnDescriptorsBits::update(bit_field3(), number)); - } - - inline JSGlobalPropertyCell* RetrieveDescriptorsPointer(); - - int EnumLength() { - return EnumLengthBits::decode(bit_field3()); - } - - void SetEnumLength(int length) { - if (length != kInvalidEnumCache) { - ASSERT(length >= 0); - ASSERT(length == 0 || instance_descriptors()->HasEnumCache()); - ASSERT(length <= NumberOfOwnDescriptors()); - } - set_bit_field3(EnumLengthBits::update(bit_field3(), length)); - } - - inline bool CanTrackAllocationSite(); - inline bool owns_descriptors(); - inline void set_owns_descriptors(bool is_shared); - inline bool is_observed(); - inline void set_is_observed(bool is_observed); - - MUST_USE_RESULT MaybeObject* RawCopy(int instance_size); - MUST_USE_RESULT MaybeObject* CopyWithPreallocatedFieldDescriptors(); - MUST_USE_RESULT MaybeObject* CopyDropDescriptors(); - MUST_USE_RESULT MaybeObject* CopyReplaceDescriptors( - DescriptorArray* descriptors, - String* name, - TransitionFlag flag, - int descriptor_index); - MUST_USE_RESULT MaybeObject* ShareDescriptor(DescriptorArray* descriptors, - Descriptor* descriptor); - MUST_USE_RESULT MaybeObject* CopyAddDescriptor(Descriptor* descriptor, - TransitionFlag flag); - MUST_USE_RESULT MaybeObject* CopyInsertDescriptor(Descriptor* descriptor, - TransitionFlag flag); - MUST_USE_RESULT MaybeObject* CopyReplaceDescriptor( - DescriptorArray* descriptors, - Descriptor* descriptor, - int index, - TransitionFlag flag); - MUST_USE_RESULT MaybeObject* CopyAsElementsKind(ElementsKind kind, - TransitionFlag flag); - - MUST_USE_RESULT MaybeObject* CopyNormalized(PropertyNormalizationMode mode, - NormalizedMapSharingMode sharing); - - inline void AppendDescriptor(Descriptor* desc, - const DescriptorArray::WhitenessWitness&); - - // Returns a copy of the map, with all transitions dropped from the - // instance descriptors. - MUST_USE_RESULT MaybeObject* Copy(); - - // Returns the property index for name (only valid for FAST MODE). - int PropertyIndexFor(String* name); - - // Returns the next free property index (only valid for FAST MODE). - int NextFreePropertyIndex(); - - // Returns the number of properties described in instance_descriptors - // filtering out properties with the specified attributes. - int NumberOfDescribedProperties(DescriptorFlag which = OWN_DESCRIPTORS, - PropertyAttributes filter = NONE); - - // Casting. - static inline Map* cast(Object* obj); - - // Locate an accessor in the instance descriptor. - AccessorDescriptor* FindAccessor(String* name); - - // Code cache operations. - - // Clears the code cache. - inline void ClearCodeCache(Heap* heap); - - // Update code cache. - static void UpdateCodeCache(Handle<Map> map, - Handle<String> name, - Handle<Code> code); - MUST_USE_RESULT MaybeObject* UpdateCodeCache(String* name, Code* code); - - // Extend the descriptor array of the map with the list of descriptors. - // In case of duplicates, the latest descriptor is used. - static void AppendCallbackDescriptors(Handle<Map> map, - Handle<Object> descriptors); - - static void EnsureDescriptorSlack(Handle<Map> map, int slack); - - // Returns the found code or undefined if absent. - Object* FindInCodeCache(String* name, Code::Flags flags); - - // Returns the non-negative index of the code object if it is in the - // cache and -1 otherwise. - int IndexInCodeCache(Object* name, Code* code); - - // Removes a code object from the code cache at the given index. - void RemoveFromCodeCache(String* name, Code* code, int index); - - // Set all map transitions from this map to dead maps to null. Also clear - // back pointers in transition targets so that we do not process this map - // again while following back pointers. - void ClearNonLiveTransitions(Heap* heap); - - // Computes a hash value for this map, to be used in HashTables and such. - int Hash(); - - // Compares this map to another to see if they describe equivalent objects. - // If |mode| is set to CLEAR_INOBJECT_PROPERTIES, |other| is treated as if - // it had exactly zero inobject properties. - // The "shared" flags of both this map and |other| are ignored. - bool EquivalentToForNormalization(Map* other, PropertyNormalizationMode mode); - - // Returns the map that this map transitions to if its elements_kind - // is changed to |elements_kind|, or NULL if no such map is cached yet. - // |safe_to_add_transitions| is set to false if adding transitions is not - // allowed. - Map* LookupElementsTransitionMap(ElementsKind elements_kind); - - // Returns the transitioned map for this map with the most generic - // elements_kind that's found in |candidates|, or null handle if no match is - // found at all. - Handle<Map> FindTransitionedMap(MapHandleList* candidates); - Map* FindTransitionedMap(MapList* candidates); - - // Zaps the contents of backing data structures. Note that the - // heap verifier (i.e. VerifyMarkingVisitor) relies on zapping of objects - // holding weak references when incremental marking is used, because it also - // iterates over objects that are otherwise unreachable. - // In general we only want to call these functions in release mode when - // heap verification is turned on. - void ZapPrototypeTransitions(); - void ZapTransitions(); - - bool CanTransition() { - // Only JSObject and subtypes have map transitions and back pointers. - STATIC_ASSERT(LAST_TYPE == LAST_JS_OBJECT_TYPE); - return instance_type() >= FIRST_JS_OBJECT_TYPE; - } - - // Fires when the layout of an object with a leaf map changes. - // This includes adding transitions to the leaf map or changing - // the descriptor array. - inline void NotifyLeafMapLayoutChange(); - - inline bool CanOmitPrototypeChecks(); - - inline void AddDependentCode(DependentCode::DependencyGroup group, - Handle<Code> code); - - // Dispatched behavior. - DECLARE_PRINTER(Map) - DECLARE_VERIFIER(Map) - -#ifdef VERIFY_HEAP - void SharedMapVerify(); - void VerifyOmittedPrototypeChecks(); -#endif - - inline int visitor_id(); - inline void set_visitor_id(int visitor_id); - - typedef void (*TraverseCallback)(Map* map, void* data); - - void TraverseTransitionTree(TraverseCallback callback, void* data); - - // When you set the prototype of an object using the __proto__ accessor you - // need a new map for the object (the prototype is stored in the map). In - // order not to multiply maps unnecessarily we store these as transitions in - // the original map. That way we can transition to the same map if the same - // prototype is set, rather than creating a new map every time. The - // transitions are in the form of a map where the keys are prototype objects - // and the values are the maps the are transitioned to. - static const int kMaxCachedPrototypeTransitions = 256; - - Map* GetPrototypeTransition(Object* prototype); - - MUST_USE_RESULT MaybeObject* PutPrototypeTransition(Object* prototype, - Map* map); - - static const int kMaxPreAllocatedPropertyFields = 255; - - // Constant for denoting that the enum cache is not yet initialized. - static const int kInvalidEnumCache = EnumLengthBits::kMax; - - // Layout description. - static const int kInstanceSizesOffset = HeapObject::kHeaderSize; - static const int kInstanceAttributesOffset = kInstanceSizesOffset + kIntSize; - static const int kPrototypeOffset = kInstanceAttributesOffset + kIntSize; - static const int kConstructorOffset = kPrototypeOffset + kPointerSize; - // Storage for the transition array is overloaded to directly contain a back - // pointer if unused. When the map has transitions, the back pointer is - // transferred to the transition array and accessed through an extra - // indirection. - static const int kTransitionsOrBackPointerOffset = - kConstructorOffset + kPointerSize; - static const int kDescriptorsOffset = - kTransitionsOrBackPointerOffset + kPointerSize; - static const int kCodeCacheOffset = kDescriptorsOffset + kPointerSize; - static const int kDependentCodeOffset = kCodeCacheOffset + kPointerSize; - static const int kBitField3Offset = kDependentCodeOffset + kPointerSize; - static const int kSize = kBitField3Offset + kPointerSize; - - // Layout of pointer fields. Heap iteration code relies on them - // being continuously allocated. - static const int kPointerFieldsBeginOffset = Map::kPrototypeOffset; - static const int kPointerFieldsEndOffset = kBitField3Offset + kPointerSize; - - // Byte offsets within kInstanceSizesOffset. - static const int kInstanceSizeOffset = kInstanceSizesOffset + 0; - static const int kInObjectPropertiesByte = 1; - static const int kInObjectPropertiesOffset = - kInstanceSizesOffset + kInObjectPropertiesByte; - static const int kPreAllocatedPropertyFieldsByte = 2; - static const int kPreAllocatedPropertyFieldsOffset = - kInstanceSizesOffset + kPreAllocatedPropertyFieldsByte; - static const int kVisitorIdByte = 3; - static const int kVisitorIdOffset = kInstanceSizesOffset + kVisitorIdByte; - - // Byte offsets within kInstanceAttributesOffset attributes. - static const int kInstanceTypeOffset = kInstanceAttributesOffset + 0; - static const int kUnusedPropertyFieldsOffset = kInstanceAttributesOffset + 1; - static const int kBitFieldOffset = kInstanceAttributesOffset + 2; - static const int kBitField2Offset = kInstanceAttributesOffset + 3; - - STATIC_CHECK(kInstanceTypeOffset == Internals::kMapInstanceTypeOffset); - - // Bit positions for bit field. - static const int kUnused = 0; // To be used for marking recently used maps. - static const int kHasNonInstancePrototype = 1; - static const int kIsHiddenPrototype = 2; - static const int kHasNamedInterceptor = 3; - static const int kHasIndexedInterceptor = 4; - static const int kIsUndetectable = 5; - static const int kHasExternalResource = 6; - static const int kIsAccessCheckNeeded = 7; - - // Bit positions for bit field 2 - static const int kIsExtensible = 0; - static const int kStringWrapperSafeForDefaultValueOf = 1; - static const int kUseUserObjectComparison = 2; - // No bits can be used after kElementsKindFirstBit, they are all reserved for - // storing ElementKind. - static const int kElementsKindShift = 3; - static const int kElementsKindBitCount = 5; - - // Derived values from bit field 2 - static const int kElementsKindMask = (-1 << kElementsKindShift) & - ((1 << (kElementsKindShift + kElementsKindBitCount)) - 1); - static const int8_t kMaximumBitField2FastElementValue = static_cast<int8_t>( - (FAST_ELEMENTS + 1) << Map::kElementsKindShift) - 1; - static const int8_t kMaximumBitField2FastSmiElementValue = - static_cast<int8_t>((FAST_SMI_ELEMENTS + 1) << - Map::kElementsKindShift) - 1; - static const int8_t kMaximumBitField2FastHoleyElementValue = - static_cast<int8_t>((FAST_HOLEY_ELEMENTS + 1) << - Map::kElementsKindShift) - 1; - static const int8_t kMaximumBitField2FastHoleySmiElementValue = - static_cast<int8_t>((FAST_HOLEY_SMI_ELEMENTS + 1) << - Map::kElementsKindShift) - 1; - - typedef FixedBodyDescriptor<kPointerFieldsBeginOffset, - kPointerFieldsEndOffset, - kSize> BodyDescriptor; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(Map); -}; - - -// An abstract superclass, a marker class really, for simple structure classes. -// It doesn't carry much functionality but allows struct classes to be -// identified in the type system. -class Struct: public HeapObject { - public: - inline void InitializeBody(int object_size); - static inline Struct* cast(Object* that); -}; - - -// Script describes a script which has been added to the VM. -class Script: public Struct { - public: - // Script types. - enum Type { - TYPE_NATIVE = 0, - TYPE_EXTENSION = 1, - TYPE_NORMAL = 2 - }; - - // Script compilation types. - enum CompilationType { - COMPILATION_TYPE_HOST = 0, - COMPILATION_TYPE_EVAL = 1 - }; - - // Script compilation state. - enum CompilationState { - COMPILATION_STATE_INITIAL = 0, - COMPILATION_STATE_COMPILED = 1 - }; - - // [source]: the script source. - DECL_ACCESSORS(source, Object) - - // [name]: the script name. - DECL_ACCESSORS(name, Object) - - // [id]: the script id. - DECL_ACCESSORS(id, Object) - - // [line_offset]: script line offset in resource from where it was extracted. - DECL_ACCESSORS(line_offset, Smi) - - // [column_offset]: script column offset in resource from where it was - // extracted. - DECL_ACCESSORS(column_offset, Smi) - - // [data]: additional data associated with this script. - DECL_ACCESSORS(data, Object) - - // [context_data]: context data for the context this script was compiled in. - DECL_ACCESSORS(context_data, Object) - - // [wrapper]: the wrapper cache. - DECL_ACCESSORS(wrapper, Foreign) - - // [type]: the script type. - DECL_ACCESSORS(type, Smi) - - // [compilation]: how the the script was compiled. - DECL_ACCESSORS(compilation_type, Smi) - - // [is_compiled]: determines whether the script has already been compiled. - DECL_ACCESSORS(compilation_state, Smi) - - // [line_ends]: FixedArray of line ends positions. - DECL_ACCESSORS(line_ends, Object) - - // [eval_from_shared]: for eval scripts the shared funcion info for the - // function from which eval was called. - DECL_ACCESSORS(eval_from_shared, Object) - - // [eval_from_instructions_offset]: the instruction offset in the code for the - // function from which eval was called where eval was called. - DECL_ACCESSORS(eval_from_instructions_offset, Smi) - - static inline Script* cast(Object* obj); - - // If script source is an external string, check that the underlying - // resource is accessible. Otherwise, always return true. - inline bool HasValidSource(); - - // Dispatched behavior. - DECLARE_PRINTER(Script) - DECLARE_VERIFIER(Script) - - static const int kSourceOffset = HeapObject::kHeaderSize; - static const int kNameOffset = kSourceOffset + kPointerSize; - static const int kLineOffsetOffset = kNameOffset + kPointerSize; - static const int kColumnOffsetOffset = kLineOffsetOffset + kPointerSize; - static const int kDataOffset = kColumnOffsetOffset + kPointerSize; - static const int kContextOffset = kDataOffset + kPointerSize; - static const int kWrapperOffset = kContextOffset + kPointerSize; - static const int kTypeOffset = kWrapperOffset + kPointerSize; - static const int kCompilationTypeOffset = kTypeOffset + kPointerSize; - static const int kCompilationStateOffset = - kCompilationTypeOffset + kPointerSize; - static const int kLineEndsOffset = kCompilationStateOffset + kPointerSize; - static const int kIdOffset = kLineEndsOffset + kPointerSize; - static const int kEvalFromSharedOffset = kIdOffset + kPointerSize; - static const int kEvalFrominstructionsOffsetOffset = - kEvalFromSharedOffset + kPointerSize; - static const int kSize = kEvalFrominstructionsOffsetOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(Script); -}; - - -// List of builtin functions we want to identify to improve code -// generation. -// -// Each entry has a name of a global object property holding an object -// optionally followed by ".prototype", a name of a builtin function -// on the object (the one the id is set for), and a label. -// -// Installation of ids for the selected builtin functions is handled -// by the bootstrapper. -// -// NOTE: Order is important: math functions should be at the end of -// the list and MathFloor should be the first math function. -#define FUNCTIONS_WITH_ID_LIST(V) \ - V(Array.prototype, push, ArrayPush) \ - V(Array.prototype, pop, ArrayPop) \ - V(Function.prototype, apply, FunctionApply) \ - V(String.prototype, charCodeAt, StringCharCodeAt) \ - V(String.prototype, charAt, StringCharAt) \ - V(String, fromCharCode, StringFromCharCode) \ - V(Math, floor, MathFloor) \ - V(Math, round, MathRound) \ - V(Math, ceil, MathCeil) \ - V(Math, abs, MathAbs) \ - V(Math, log, MathLog) \ - V(Math, sin, MathSin) \ - V(Math, cos, MathCos) \ - V(Math, tan, MathTan) \ - V(Math, asin, MathASin) \ - V(Math, acos, MathACos) \ - V(Math, atan, MathATan) \ - V(Math, exp, MathExp) \ - V(Math, sqrt, MathSqrt) \ - V(Math, pow, MathPow) \ - V(Math, random, MathRandom) \ - V(Math, max, MathMax) \ - V(Math, min, MathMin) - - -enum BuiltinFunctionId { -#define DECLARE_FUNCTION_ID(ignored1, ignore2, name) \ - k##name, - FUNCTIONS_WITH_ID_LIST(DECLARE_FUNCTION_ID) -#undef DECLARE_FUNCTION_ID - // Fake id for a special case of Math.pow. Note, it continues the - // list of math functions. - kMathPowHalf, - kFirstMathFunctionId = kMathFloor -}; - - -// SharedFunctionInfo describes the JSFunction information that can be -// shared by multiple instances of the function. -class SharedFunctionInfo: public HeapObject { - public: - // [name]: Function name. - DECL_ACCESSORS(name, Object) - - // [code]: Function code. - DECL_ACCESSORS(code, Code) - inline void ReplaceCode(Code* code); - - // [optimized_code_map]: Map from native context to optimized code - // and a shared literals array or Smi 0 if none. - DECL_ACCESSORS(optimized_code_map, Object) - - // Returns index i of the entry with the specified context. At position - // i - 1 is the context, position i the code, and i + 1 the literals array. - // Returns -1 when no matching entry is found. - int SearchOptimizedCodeMap(Context* native_context); - - // Installs optimized code from the code map on the given closure. The - // index has to be consistent with a search result as defined above. - void InstallFromOptimizedCodeMap(JSFunction* function, int index); - - // Clear optimized code map. - inline void ClearOptimizedCodeMap(); - - // Add a new entry to the optimized code map. - static void AddToOptimizedCodeMap(Handle<SharedFunctionInfo> shared, - Handle<Context> native_context, - Handle<Code> code, - Handle<FixedArray> literals); - static const int kEntryLength = 3; - - // [scope_info]: Scope info. - DECL_ACCESSORS(scope_info, ScopeInfo) - - // [construct stub]: Code stub for constructing instances of this function. - DECL_ACCESSORS(construct_stub, Code) - - inline Code* unchecked_code(); - - // Returns if this function has been compiled to native code yet. - inline bool is_compiled(); - - // [length]: The function length - usually the number of declared parameters. - // Use up to 2^30 parameters. - inline int length(); - inline void set_length(int value); - - // [formal parameter count]: The declared number of parameters. - inline int formal_parameter_count(); - inline void set_formal_parameter_count(int value); - - // Set the formal parameter count so the function code will be - // called without using argument adaptor frames. - inline void DontAdaptArguments(); - - // [expected_nof_properties]: Expected number of properties for the function. - inline int expected_nof_properties(); - inline void set_expected_nof_properties(int value); - - // Inobject slack tracking is the way to reclaim unused inobject space. - // - // The instance size is initially determined by adding some slack to - // expected_nof_properties (to allow for a few extra properties added - // after the constructor). There is no guarantee that the extra space - // will not be wasted. - // - // Here is the algorithm to reclaim the unused inobject space: - // - Detect the first constructor call for this SharedFunctionInfo. - // When it happens enter the "in progress" state: remember the - // constructor's initial_map and install a special construct stub that - // counts constructor calls. - // - While the tracking is in progress create objects filled with - // one_pointer_filler_map instead of undefined_value. This way they can be - // resized quickly and safely. - // - Once enough (kGenerousAllocationCount) objects have been created - // compute the 'slack' (traverse the map transition tree starting from the - // initial_map and find the lowest value of unused_property_fields). - // - Traverse the transition tree again and decrease the instance size - // of every map. Existing objects will resize automatically (they are - // filled with one_pointer_filler_map). All further allocations will - // use the adjusted instance size. - // - Decrease expected_nof_properties so that an allocations made from - // another context will use the adjusted instance size too. - // - Exit "in progress" state by clearing the reference to the initial_map - // and setting the regular construct stub (generic or inline). - // - // The above is the main event sequence. Some special cases are possible - // while the tracking is in progress: - // - // - GC occurs. - // Check if the initial_map is referenced by any live objects (except this - // SharedFunctionInfo). If it is, continue tracking as usual. - // If it is not, clear the reference and reset the tracking state. The - // tracking will be initiated again on the next constructor call. - // - // - The constructor is called from another context. - // Immediately complete the tracking, perform all the necessary changes - // to maps. This is necessary because there is no efficient way to track - // multiple initial_maps. - // Proceed to create an object in the current context (with the adjusted - // size). - // - // - A different constructor function sharing the same SharedFunctionInfo is - // called in the same context. This could be another closure in the same - // context, or the first function could have been disposed. - // This is handled the same way as the previous case. - // - // Important: inobject slack tracking is not attempted during the snapshot - // creation. - - static const int kGenerousAllocationCount = 8; - - // [construction_count]: Counter for constructor calls made during - // the tracking phase. - inline int construction_count(); - inline void set_construction_count(int value); - - // [initial_map]: initial map of the first function called as a constructor. - // Saved for the duration of the tracking phase. - // This is a weak link (GC resets it to undefined_value if no other live - // object reference this map). - DECL_ACCESSORS(initial_map, Object) - - // True if the initial_map is not undefined and the countdown stub is - // installed. - inline bool IsInobjectSlackTrackingInProgress(); - - // Starts the tracking. - // Stores the initial map and installs the countdown stub. - // IsInobjectSlackTrackingInProgress is normally true after this call, - // except when tracking have not been started (e.g. the map has no unused - // properties or the snapshot is being built). - void StartInobjectSlackTracking(Map* map); - - // Completes the tracking. - // IsInobjectSlackTrackingInProgress is false after this call. - void CompleteInobjectSlackTracking(); - - // Invoked before pointers in SharedFunctionInfo are being marked. - // Also clears the optimized code map. - inline void BeforeVisitingPointers(); - - // Clears the initial_map before the GC marking phase to ensure the reference - // is weak. IsInobjectSlackTrackingInProgress is false after this call. - void DetachInitialMap(); - - // Restores the link to the initial map after the GC marking phase. - // IsInobjectSlackTrackingInProgress is true after this call. - void AttachInitialMap(Map* map); - - // False if there are definitely no live objects created from this function. - // True if live objects _may_ exist (existence not guaranteed). - // May go back from true to false after GC. - DECL_BOOLEAN_ACCESSORS(live_objects_may_exist) - - // [instance class name]: class name for instances. - DECL_ACCESSORS(instance_class_name, Object) - - // [function data]: This field holds some additional data for function. - // Currently it either has FunctionTemplateInfo to make benefit the API - // or Smi identifying a builtin function. - // In the long run we don't want all functions to have this field but - // we can fix that when we have a better model for storing hidden data - // on objects. - DECL_ACCESSORS(function_data, Object) - - inline bool IsApiFunction(); - inline FunctionTemplateInfo* get_api_func_data(); - inline bool HasBuiltinFunctionId(); - inline BuiltinFunctionId builtin_function_id(); - - // [script info]: Script from which the function originates. - DECL_ACCESSORS(script, Object) - - // [num_literals]: Number of literals used by this function. - inline int num_literals(); - inline void set_num_literals(int value); - - // [start_position_and_type]: Field used to store both the source code - // position, whether or not the function is a function expression, - // and whether or not the function is a toplevel function. The two - // least significants bit indicates whether the function is an - // expression and the rest contains the source code position. - inline int start_position_and_type(); - inline void set_start_position_and_type(int value); - - // [debug info]: Debug information. - DECL_ACCESSORS(debug_info, Object) - - // [inferred name]: Name inferred from variable or property - // assignment of this function. Used to facilitate debugging and - // profiling of JavaScript code written in OO style, where almost - // all functions are anonymous but are assigned to object - // properties. - DECL_ACCESSORS(inferred_name, String) - - // The function's name if it is non-empty, otherwise the inferred name. - String* DebugName(); - - // Position of the 'function' token in the script source. - inline int function_token_position(); - inline void set_function_token_position(int function_token_position); - - // Position of this function in the script source. - inline int start_position(); - inline void set_start_position(int start_position); - - // End position of this function in the script source. - inline int end_position(); - inline void set_end_position(int end_position); - - // Is this function a function expression in the source code. - DECL_BOOLEAN_ACCESSORS(is_expression) - - // Is this function a top-level function (scripts, evals). - DECL_BOOLEAN_ACCESSORS(is_toplevel) - - // Bit field containing various information collected by the compiler to - // drive optimization. - inline int compiler_hints(); - inline void set_compiler_hints(int value); - - inline int ast_node_count(); - inline void set_ast_node_count(int count); - - // A counter used to determine when to stress the deoptimizer with a - // deopt. - inline int stress_deopt_counter(); - inline void set_stress_deopt_counter(int counter); - - inline int profiler_ticks(); - - // Inline cache age is used to infer whether the function survived a context - // disposal or not. In the former case we reset the opt_count. - inline int ic_age(); - inline void set_ic_age(int age); - - // Add information on assignments of the form this.x = ...; - void SetThisPropertyAssignmentsInfo( - bool has_only_simple_this_property_assignments, - FixedArray* this_property_assignments); - - // Clear information on assignments of the form this.x = ...; - void ClearThisPropertyAssignmentsInfo(); - - // Indicate that this function only consists of assignments of the form - // this.x = y; where y is either a constant or refers to an argument. - inline bool has_only_simple_this_property_assignments(); - - // Indicates if this function can be lazy compiled. - // This is used to determine if we can safely flush code from a function - // when doing GC if we expect that the function will no longer be used. - DECL_BOOLEAN_ACCESSORS(allows_lazy_compilation) - - // Indicates if this function can be lazy compiled without a context. - // This is used to determine if we can force compilation without reaching - // the function through program execution but through other means (e.g. heap - // iteration by the debugger). - DECL_BOOLEAN_ACCESSORS(allows_lazy_compilation_without_context) - - // Indicates how many full GCs this function has survived with assigned - // code object. Used to determine when it is relatively safe to flush - // this code object and replace it with lazy compilation stub. - // Age is reset when GC notices that the code object is referenced - // from the stack or compilation cache. - inline int code_age(); - inline void set_code_age(int age); - - // Indicates whether optimizations have been disabled for this - // shared function info. If a function is repeatedly optimized or if - // we cannot optimize the function we disable optimization to avoid - // spending time attempting to optimize it again. - DECL_BOOLEAN_ACCESSORS(optimization_disabled) - - // Indicates the language mode of the function's code as defined by the - // current harmony drafts for the next ES language standard. Possible - // values are: - // 1. CLASSIC_MODE - Unrestricted syntax and semantics, same as in ES5. - // 2. STRICT_MODE - Restricted syntax and semantics, same as in ES5. - // 3. EXTENDED_MODE - Only available under the harmony flag, not part of ES5. - inline LanguageMode language_mode(); - inline void set_language_mode(LanguageMode language_mode); - - // Indicates whether the language mode of this function is CLASSIC_MODE. - inline bool is_classic_mode(); - - // Indicates whether the language mode of this function is EXTENDED_MODE. - inline bool is_extended_mode(); - - // Indicates whether the function is a qml mode function. - DECL_BOOLEAN_ACCESSORS(qml_mode) - - // False if the function definitely does not allocate an arguments object. - DECL_BOOLEAN_ACCESSORS(uses_arguments) - - // True if the function has any duplicated parameter names. - DECL_BOOLEAN_ACCESSORS(has_duplicate_parameters) - - // Indicates whether the function is a native function. - // These needs special treatment in .call and .apply since - // null passed as the receiver should not be translated to the - // global object. - DECL_BOOLEAN_ACCESSORS(native) - - // Indicates that the function was created by the Function function. - // Though it's anonymous, toString should treat it as if it had the name - // "anonymous". We don't set the name itself so that the system does not - // see a binding for it. - DECL_BOOLEAN_ACCESSORS(name_should_print_as_anonymous) - - // Indicates whether the function is a bound function created using - // the bind function. - DECL_BOOLEAN_ACCESSORS(bound) - - // Indicates that the function is anonymous (the name field can be set - // through the API, which does not change this flag). - DECL_BOOLEAN_ACCESSORS(is_anonymous) - - // Is this a function or top-level/eval code. - DECL_BOOLEAN_ACCESSORS(is_function) - - // Indicates that the function cannot be optimized. - DECL_BOOLEAN_ACCESSORS(dont_optimize) - - // Indicates that the function cannot be inlined. - DECL_BOOLEAN_ACCESSORS(dont_inline) - - // Indicates that code for this function cannot be cached. - DECL_BOOLEAN_ACCESSORS(dont_cache) - - // Indicates whether or not the code in the shared function support - // deoptimization. - inline bool has_deoptimization_support(); - - // Enable deoptimization support through recompiled code. - void EnableDeoptimizationSupport(Code* recompiled); - - // Disable (further) attempted optimization of all functions sharing this - // shared function info. - void DisableOptimization(const char* reason); - - // Lookup the bailout ID and ASSERT that it exists in the non-optimized - // code, returns whether it asserted (i.e., always true if assertions are - // disabled). - bool VerifyBailoutId(BailoutId id); - - // Check whether a inlined constructor can be generated with the given - // prototype. - bool CanGenerateInlineConstructor(Object* prototype); - - // Prevents further attempts to generate inline constructors. - // To be called if generation failed for any reason. - void ForbidInlineConstructor(); - - // For functions which only contains this property assignments this provides - // access to the names for the properties assigned. - DECL_ACCESSORS(this_property_assignments, Object) - inline int this_property_assignments_count(); - inline void set_this_property_assignments_count(int value); - String* GetThisPropertyAssignmentName(int index); - bool IsThisPropertyAssignmentArgument(int index); - int GetThisPropertyAssignmentArgument(int index); - Object* GetThisPropertyAssignmentConstant(int index); - - // [source code]: Source code for the function. - bool HasSourceCode(); - Handle<Object> GetSourceCode(); - - // Number of times the function was optimized. - inline int opt_count(); - inline void set_opt_count(int opt_count); - - // Number of times the function was deoptimized. - inline void set_deopt_count(int value); - inline int deopt_count(); - inline void increment_deopt_count(); - - // Number of time we tried to re-enable optimization after it - // was disabled due to high number of deoptimizations. - inline void set_opt_reenable_tries(int value); - inline int opt_reenable_tries(); - - inline void TryReenableOptimization(); - - // Stores deopt_count, opt_reenable_tries and ic_age as bit-fields. - inline void set_counters(int value); - inline int counters(); - - // Source size of this function. - int SourceSize(); - - // Calculate the instance size. - int CalculateInstanceSize(); - - // Calculate the number of in-object properties. - int CalculateInObjectProperties(); - - // Dispatched behavior. - // Set max_length to -1 for unlimited length. - void SourceCodePrint(StringStream* accumulator, int max_length); - DECLARE_PRINTER(SharedFunctionInfo) - DECLARE_VERIFIER(SharedFunctionInfo) - - void ResetForNewContext(int new_ic_age); - - // Helper to compile the shared code. Returns true on success, false on - // failure (e.g., stack overflow during compilation). This is only used by - // the debugger, it is not possible to compile without a context otherwise. - static bool CompileLazy(Handle<SharedFunctionInfo> shared, - ClearExceptionFlag flag); - - // Casting. - static inline SharedFunctionInfo* cast(Object* obj); - - // Constants. - static const int kDontAdaptArgumentsSentinel = -1; - - // Layout description. - // Pointer fields. - static const int kNameOffset = HeapObject::kHeaderSize; - static const int kCodeOffset = kNameOffset + kPointerSize; - static const int kOptimizedCodeMapOffset = kCodeOffset + kPointerSize; - static const int kScopeInfoOffset = kOptimizedCodeMapOffset + kPointerSize; - static const int kConstructStubOffset = kScopeInfoOffset + kPointerSize; - static const int kInstanceClassNameOffset = - kConstructStubOffset + kPointerSize; - static const int kFunctionDataOffset = - kInstanceClassNameOffset + kPointerSize; - static const int kScriptOffset = kFunctionDataOffset + kPointerSize; - static const int kDebugInfoOffset = kScriptOffset + kPointerSize; - static const int kInferredNameOffset = kDebugInfoOffset + kPointerSize; - static const int kInitialMapOffset = - kInferredNameOffset + kPointerSize; - static const int kThisPropertyAssignmentsOffset = - kInitialMapOffset + kPointerSize; - // ast_node_count is a Smi field. It could be grouped with another Smi field - // into a PSEUDO_SMI_ACCESSORS pair (on x64), if one becomes available. - static const int kAstNodeCountOffset = - kThisPropertyAssignmentsOffset + kPointerSize; -#if V8_HOST_ARCH_32_BIT - // Smi fields. - static const int kLengthOffset = - kAstNodeCountOffset + kPointerSize; - static const int kFormalParameterCountOffset = kLengthOffset + kPointerSize; - static const int kExpectedNofPropertiesOffset = - kFormalParameterCountOffset + kPointerSize; - static const int kNumLiteralsOffset = - kExpectedNofPropertiesOffset + kPointerSize; - static const int kStartPositionAndTypeOffset = - kNumLiteralsOffset + kPointerSize; - static const int kEndPositionOffset = - kStartPositionAndTypeOffset + kPointerSize; - static const int kFunctionTokenPositionOffset = - kEndPositionOffset + kPointerSize; - static const int kCompilerHintsOffset = - kFunctionTokenPositionOffset + kPointerSize; - static const int kThisPropertyAssignmentsCountOffset = - kCompilerHintsOffset + kPointerSize; - static const int kOptCountOffset = - kThisPropertyAssignmentsCountOffset + kPointerSize; - static const int kCountersOffset = kOptCountOffset + kPointerSize; - static const int kStressDeoptCounterOffset = kCountersOffset + kPointerSize; - - // Total size. - static const int kSize = kStressDeoptCounterOffset + kPointerSize; -#else - // The only reason to use smi fields instead of int fields - // is to allow iteration without maps decoding during - // garbage collections. - // To avoid wasting space on 64-bit architectures we use - // the following trick: we group integer fields into pairs - // First integer in each pair is shifted left by 1. - // By doing this we guarantee that LSB of each kPointerSize aligned - // word is not set and thus this word cannot be treated as pointer - // to HeapObject during old space traversal. - static const int kLengthOffset = - kAstNodeCountOffset + kPointerSize; - static const int kFormalParameterCountOffset = - kLengthOffset + kIntSize; - - static const int kExpectedNofPropertiesOffset = - kFormalParameterCountOffset + kIntSize; - static const int kNumLiteralsOffset = - kExpectedNofPropertiesOffset + kIntSize; - - static const int kEndPositionOffset = - kNumLiteralsOffset + kIntSize; - static const int kStartPositionAndTypeOffset = - kEndPositionOffset + kIntSize; - - static const int kFunctionTokenPositionOffset = - kStartPositionAndTypeOffset + kIntSize; - static const int kCompilerHintsOffset = - kFunctionTokenPositionOffset + kIntSize; - - static const int kThisPropertyAssignmentsCountOffset = - kCompilerHintsOffset + kIntSize; - static const int kOptCountOffset = - kThisPropertyAssignmentsCountOffset + kIntSize; - - static const int kCountersOffset = kOptCountOffset + kIntSize; - static const int kStressDeoptCounterOffset = kCountersOffset + kIntSize; - - // Total size. - static const int kSize = kStressDeoptCounterOffset + kIntSize; - -#endif - - // The construction counter for inobject slack tracking is stored in the - // most significant byte of compiler_hints which is otherwise unused. - // Its offset depends on the endian-ness of the architecture. -#if __BYTE_ORDER == __LITTLE_ENDIAN - static const int kConstructionCountOffset = kCompilerHintsOffset + 3; -#elif __BYTE_ORDER == __BIG_ENDIAN - static const int kConstructionCountOffset = kCompilerHintsOffset + 0; -#else -#error Unknown byte ordering -#endif - - static const int kAlignedSize = POINTER_SIZE_ALIGN(kSize); - - typedef FixedBodyDescriptor<kNameOffset, - kThisPropertyAssignmentsOffset + kPointerSize, - kSize> BodyDescriptor; - - // Bit positions in start_position_and_type. - // The source code start position is in the 30 most significant bits of - // the start_position_and_type field. - static const int kIsExpressionBit = 0; - static const int kIsTopLevelBit = 1; - static const int kStartPositionShift = 2; - static const int kStartPositionMask = ~((1 << kStartPositionShift) - 1); - - // Bit positions in compiler_hints. - static const int kCodeAgeSize = 3; - static const int kCodeAgeMask = (1 << kCodeAgeSize) - 1; - - enum CompilerHints { - kHasOnlySimpleThisPropertyAssignments, - kAllowLazyCompilation, - kAllowLazyCompilationWithoutContext, - kLiveObjectsMayExist, - kCodeAgeShift, - kOptimizationDisabled = kCodeAgeShift + kCodeAgeSize, - kStrictModeFunction, - kExtendedModeFunction, - kQmlModeFunction, - kUsesArguments, - kHasDuplicateParameters, - kNative, - kBoundFunction, - kIsAnonymous, - kNameShouldPrintAsAnonymous, - kIsFunction, - kDontOptimize, - kDontInline, - kDontCache, - kCompilerHintsCount // Pseudo entry - }; - - class DeoptCountBits: public BitField<int, 0, 4> {}; - class OptReenableTriesBits: public BitField<int, 4, 18> {}; - class ICAgeBits: public BitField<int, 22, 8> {}; - - private: -#if V8_HOST_ARCH_32_BIT - // On 32 bit platforms, compiler hints is a smi. - static const int kCompilerHintsSmiTagSize = kSmiTagSize; - static const int kCompilerHintsSize = kPointerSize; -#else - // On 64 bit platforms, compiler hints is not a smi, see comment above. - static const int kCompilerHintsSmiTagSize = 0; - static const int kCompilerHintsSize = kIntSize; -#endif - - STATIC_ASSERT(SharedFunctionInfo::kCompilerHintsCount <= - SharedFunctionInfo::kCompilerHintsSize * kBitsPerByte); - - public: - // Constants for optimizing codegen for strict mode function and - // native tests. - // Allows to use byte-width instructions. - static const int kStrictModeBitWithinByte = - (kStrictModeFunction + kCompilerHintsSmiTagSize) % kBitsPerByte; - - static const int kExtendedModeBitWithinByte = - (kExtendedModeFunction + kCompilerHintsSmiTagSize) % kBitsPerByte; - - static const int kNativeBitWithinByte = - (kNative + kCompilerHintsSmiTagSize) % kBitsPerByte; - -#if __BYTE_ORDER == __LITTLE_ENDIAN - static const int kStrictModeByteOffset = kCompilerHintsOffset + - (kStrictModeFunction + kCompilerHintsSmiTagSize) / kBitsPerByte; - static const int kExtendedModeByteOffset = kCompilerHintsOffset + - (kExtendedModeFunction + kCompilerHintsSmiTagSize) / kBitsPerByte; - static const int kNativeByteOffset = kCompilerHintsOffset + - (kNative + kCompilerHintsSmiTagSize) / kBitsPerByte; -#elif __BYTE_ORDER == __BIG_ENDIAN - static const int kStrictModeByteOffset = kCompilerHintsOffset + - (kCompilerHintsSize - 1) - - ((kStrictModeFunction + kCompilerHintsSmiTagSize) / kBitsPerByte); - static const int kExtendedModeByteOffset = kCompilerHintsOffset + - (kCompilerHintsSize - 1) - - ((kExtendedModeFunction + kCompilerHintsSmiTagSize) / kBitsPerByte); - static const int kNativeByteOffset = kCompilerHintsOffset + - (kCompilerHintsSize - 1) - - ((kNative + kCompilerHintsSmiTagSize) / kBitsPerByte); -#else -#error Unknown byte ordering -#endif - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(SharedFunctionInfo); -}; - - -// Representation for module instance objects. -class JSModule: public JSObject { - public: - // [context]: the context holding the module's locals, or undefined if none. - DECL_ACCESSORS(context, Object) - - // [scope_info]: Scope info. - DECL_ACCESSORS(scope_info, ScopeInfo) - - // Casting. - static inline JSModule* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSModule) - DECLARE_VERIFIER(JSModule) - - // Layout description. - static const int kContextOffset = JSObject::kHeaderSize; - static const int kScopeInfoOffset = kContextOffset + kPointerSize; - static const int kSize = kScopeInfoOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSModule); -}; - - -// JSFunction describes JavaScript functions. -class JSFunction: public JSObject { - public: - // [prototype_or_initial_map]: - DECL_ACCESSORS(prototype_or_initial_map, Object) - - // [shared]: The information about the function that - // can be shared by instances. - DECL_ACCESSORS(shared, SharedFunctionInfo) - - inline SharedFunctionInfo* unchecked_shared(); - - // [context]: The context for this function. - inline Context* context(); - inline Object* unchecked_context(); - inline void set_context(Object* context); - - // [code]: The generated code object for this function. Executed - // when the function is invoked, e.g. foo() or new foo(). See - // [[Call]] and [[Construct]] description in ECMA-262, section - // 8.6.2, page 27. - inline Code* code(); - inline void set_code(Code* code); - inline void ReplaceCode(Code* code); - - inline Code* unchecked_code(); - - // Tells whether this function is builtin. - inline bool IsBuiltin(); - - // Tells whether or not the function needs arguments adaption. - inline bool NeedsArgumentsAdaption(); - - // Tells whether or not this function has been optimized. - inline bool IsOptimized(); - - // Tells whether or not this function can be optimized. - inline bool IsOptimizable(); - - // Mark this function for lazy recompilation. The function will be - // recompiled the next time it is executed. - void MarkForLazyRecompilation(); - void MarkForParallelRecompilation(); - - // Helpers to compile this function. Returns true on success, false on - // failure (e.g., stack overflow during compilation). - static bool EnsureCompiled(Handle<JSFunction> function, - ClearExceptionFlag flag); - static bool CompileLazy(Handle<JSFunction> function, - ClearExceptionFlag flag); - static bool CompileOptimized(Handle<JSFunction> function, - BailoutId osr_ast_id, - ClearExceptionFlag flag); - - // Tells whether or not the function is already marked for lazy - // recompilation. - inline bool IsMarkedForLazyRecompilation(); - inline bool IsMarkedForParallelRecompilation(); - - // Tells whether or not the function is on the parallel - // recompilation queue. - inline bool IsInRecompileQueue(); - - // Check whether or not this function is inlineable. - bool IsInlineable(); - - // [literals_or_bindings]: Fixed array holding either - // the materialized literals or the bindings of a bound function. - // - // If the function contains object, regexp or array literals, the - // literals array prefix contains the object, regexp, and array - // function to be used when creating these literals. This is - // necessary so that we do not dynamically lookup the object, regexp - // or array functions. Performing a dynamic lookup, we might end up - // using the functions from a new context that we should not have - // access to. - // - // On bound functions, the array is a (copy-on-write) fixed-array containing - // the function that was bound, bound this-value and any bound - // arguments. Bound functions never contain literals. - DECL_ACCESSORS(literals_or_bindings, FixedArray) - - inline FixedArray* literals(); - inline void set_literals(FixedArray* literals); - - inline FixedArray* function_bindings(); - inline void set_function_bindings(FixedArray* bindings); - - // The initial map for an object created by this constructor. - inline Map* initial_map(); - inline void set_initial_map(Map* value); - inline bool has_initial_map(); - - // Get and set the prototype property on a JSFunction. If the - // function has an initial map the prototype is set on the initial - // map. Otherwise, the prototype is put in the initial map field - // until an initial map is needed. - inline bool has_prototype(); - inline bool has_instance_prototype(); - inline Object* prototype(); - inline Object* instance_prototype(); - MUST_USE_RESULT MaybeObject* SetInstancePrototype(Object* value); - MUST_USE_RESULT MaybeObject* SetPrototype(Object* value); - - // After prototype is removed, it will not be created when accessed, and - // [[Construct]] from this function will not be allowed. - void RemovePrototype(); - inline bool should_have_prototype(); - - // Accessor for this function's initial map's [[class]] - // property. This is primarily used by ECMA native functions. This - // method sets the class_name field of this function's initial map - // to a given value. It creates an initial map if this function does - // not have one. Note that this method does not copy the initial map - // if it has one already, but simply replaces it with the new value. - // Instances created afterwards will have a map whose [[class]] is - // set to 'value', but there is no guarantees on instances created - // before. - void SetInstanceClassName(String* name); - - // Returns if this function has been compiled to native code yet. - inline bool is_compiled(); - - // [next_function_link]: Field for linking functions. This list is treated as - // a weak list by the GC. - DECL_ACCESSORS(next_function_link, Object) - - // Prints the name of the function using PrintF. - inline void PrintName() { - PrintName(stdout); - } - void PrintName(FILE* out); - - // Casting. - static inline JSFunction* cast(Object* obj); - - // Iterates the objects, including code objects indirectly referenced - // through pointers to the first instruction in the code object. - void JSFunctionIterateBody(int object_size, ObjectVisitor* v); - - // Dispatched behavior. - DECLARE_PRINTER(JSFunction) - DECLARE_VERIFIER(JSFunction) - - // Returns the number of allocated literals. - inline int NumberOfLiterals(); - - // Retrieve the native context from a function's literal array. - static Context* NativeContextFromLiterals(FixedArray* literals); - -#ifdef DEBUG - bool FunctionsInFunctionListShareSameCode() { - Object* current = this; - while (!current->IsUndefined()) { - JSFunction* function = JSFunction::cast(current); - current = function->next_function_link(); - if (function->code() != this->code()) return false; - } - return true; - } -#endif - - // Layout descriptors. The last property (from kNonWeakFieldsEndOffset to - // kSize) is weak and has special handling during garbage collection. - static const int kCodeEntryOffset = JSObject::kHeaderSize; - static const int kPrototypeOrInitialMapOffset = - kCodeEntryOffset + kPointerSize; - static const int kSharedFunctionInfoOffset = - kPrototypeOrInitialMapOffset + kPointerSize; - static const int kContextOffset = kSharedFunctionInfoOffset + kPointerSize; - static const int kLiteralsOffset = kContextOffset + kPointerSize; - static const int kNonWeakFieldsEndOffset = kLiteralsOffset + kPointerSize; - static const int kNextFunctionLinkOffset = kNonWeakFieldsEndOffset; - static const int kSize = kNextFunctionLinkOffset + kPointerSize; - - // Layout of the literals array. - static const int kLiteralsPrefixSize = 1; - static const int kLiteralNativeContextIndex = 0; - - // Layout of the bound-function binding array. - static const int kBoundFunctionIndex = 0; - static const int kBoundThisIndex = 1; - static const int kBoundArgumentsStartIndex = 2; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSFunction); -}; - - -// JSGlobalProxy's prototype must be a JSGlobalObject or null, -// and the prototype is hidden. JSGlobalProxy always delegates -// property accesses to its prototype if the prototype is not null. -// -// A JSGlobalProxy can be reinitialized which will preserve its identity. -// -// Accessing a JSGlobalProxy requires security check. - -class JSGlobalProxy : public JSObject { - public: - // [native_context]: the owner native context of this global proxy object. - // It is null value if this object is not used by any context. - DECL_ACCESSORS(native_context, Object) - - // Casting. - static inline JSGlobalProxy* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSGlobalProxy) - DECLARE_VERIFIER(JSGlobalProxy) - - // Layout description. - static const int kNativeContextOffset = JSObject::kHeaderSize; - static const int kSize = kNativeContextOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSGlobalProxy); -}; - - -// Forward declaration. -class JSBuiltinsObject; - -// Common super class for JavaScript global objects and the special -// builtins global objects. -class GlobalObject: public JSObject { - public: - // [builtins]: the object holding the runtime routines written in JS. - DECL_ACCESSORS(builtins, JSBuiltinsObject) - - // [native context]: the natives corresponding to this global object. - DECL_ACCESSORS(native_context, Context) - - // [global context]: the most recent (i.e. innermost) global context. - DECL_ACCESSORS(global_context, Context) - - // [global receiver]: the global receiver object of the context - DECL_ACCESSORS(global_receiver, JSObject) - - // Retrieve the property cell used to store a property. - JSGlobalPropertyCell* GetPropertyCell(LookupResult* result); - - // This is like GetProperty, but is used when you know the lookup won't fail - // by throwing an exception. This is for the debug and builtins global - // objects, where it is known which properties can be expected to be present - // on the object. - Object* GetPropertyNoExceptionThrown(String* key) { - Object* answer = GetProperty(key)->ToObjectUnchecked(); - return answer; - } - - // Ensure that the global object has a cell for the given property name. - static Handle<JSGlobalPropertyCell> EnsurePropertyCell( - Handle<GlobalObject> global, - Handle<String> name); - // TODO(kmillikin): This function can be eliminated once the stub cache is - // fully handlified (and the static helper can be written directly). - MUST_USE_RESULT MaybeObject* EnsurePropertyCell(String* name); - - // Casting. - static inline GlobalObject* cast(Object* obj); - - // Layout description. - static const int kBuiltinsOffset = JSObject::kHeaderSize; - static const int kNativeContextOffset = kBuiltinsOffset + kPointerSize; - static const int kGlobalContextOffset = kNativeContextOffset + kPointerSize; - static const int kGlobalReceiverOffset = kGlobalContextOffset + kPointerSize; - static const int kHeaderSize = kGlobalReceiverOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(GlobalObject); -}; - - -// JavaScript global object. -class JSGlobalObject: public GlobalObject { - public: - // Casting. - static inline JSGlobalObject* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSGlobalObject) - DECLARE_VERIFIER(JSGlobalObject) - - // Layout description. - static const int kSize = GlobalObject::kHeaderSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSGlobalObject); -}; - - -// Builtins global object which holds the runtime routines written in -// JavaScript. -class JSBuiltinsObject: public GlobalObject { - public: - // Accessors for the runtime routines written in JavaScript. - inline Object* javascript_builtin(Builtins::JavaScript id); - inline void set_javascript_builtin(Builtins::JavaScript id, Object* value); - - // Accessors for code of the runtime routines written in JavaScript. - inline Code* javascript_builtin_code(Builtins::JavaScript id); - inline void set_javascript_builtin_code(Builtins::JavaScript id, Code* value); - - // Casting. - static inline JSBuiltinsObject* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSBuiltinsObject) - DECLARE_VERIFIER(JSBuiltinsObject) - - // Layout description. The size of the builtins object includes - // room for two pointers per runtime routine written in javascript - // (function and code object). - static const int kJSBuiltinsCount = Builtins::id_count; - static const int kJSBuiltinsOffset = GlobalObject::kHeaderSize; - static const int kJSBuiltinsCodeOffset = - GlobalObject::kHeaderSize + (kJSBuiltinsCount * kPointerSize); - static const int kSize = - kJSBuiltinsCodeOffset + (kJSBuiltinsCount * kPointerSize); - - static int OffsetOfFunctionWithId(Builtins::JavaScript id) { - return kJSBuiltinsOffset + id * kPointerSize; - } - - static int OffsetOfCodeWithId(Builtins::JavaScript id) { - return kJSBuiltinsCodeOffset + id * kPointerSize; - } - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSBuiltinsObject); -}; - - -// Representation for JS Wrapper objects, String, Number, Boolean, etc. -class JSValue: public JSObject { - public: - // [value]: the object being wrapped. - DECL_ACCESSORS(value, Object) - - // Casting. - static inline JSValue* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSValue) - DECLARE_VERIFIER(JSValue) - - // Layout description. - static const int kValueOffset = JSObject::kHeaderSize; - static const int kSize = kValueOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSValue); -}; - - -class DateCache; - -// Representation for JS date objects. -class JSDate: public JSObject { - public: - // If one component is NaN, all of them are, indicating a NaN time value. - // [value]: the time value. - DECL_ACCESSORS(value, Object) - // [year]: caches year. Either undefined, smi, or NaN. - DECL_ACCESSORS(year, Object) - // [month]: caches month. Either undefined, smi, or NaN. - DECL_ACCESSORS(month, Object) - // [day]: caches day. Either undefined, smi, or NaN. - DECL_ACCESSORS(day, Object) - // [weekday]: caches day of week. Either undefined, smi, or NaN. - DECL_ACCESSORS(weekday, Object) - // [hour]: caches hours. Either undefined, smi, or NaN. - DECL_ACCESSORS(hour, Object) - // [min]: caches minutes. Either undefined, smi, or NaN. - DECL_ACCESSORS(min, Object) - // [sec]: caches seconds. Either undefined, smi, or NaN. - DECL_ACCESSORS(sec, Object) - // [cache stamp]: sample of the date cache stamp at the - // moment when local fields were cached. - DECL_ACCESSORS(cache_stamp, Object) - - // Casting. - static inline JSDate* cast(Object* obj); - - // Returns the date field with the specified index. - // See FieldIndex for the list of date fields. - static Object* GetField(Object* date, Smi* index); - - void SetValue(Object* value, bool is_value_nan); - - - // Dispatched behavior. - DECLARE_PRINTER(JSDate) - DECLARE_VERIFIER(JSDate) - - // The order is important. It must be kept in sync with date macros - // in macros.py. - enum FieldIndex { - kDateValue, - kYear, - kMonth, - kDay, - kWeekday, - kHour, - kMinute, - kSecond, - kFirstUncachedField, - kMillisecond = kFirstUncachedField, - kDays, - kTimeInDay, - kFirstUTCField, - kYearUTC = kFirstUTCField, - kMonthUTC, - kDayUTC, - kWeekdayUTC, - kHourUTC, - kMinuteUTC, - kSecondUTC, - kMillisecondUTC, - kDaysUTC, - kTimeInDayUTC, - kTimezoneOffset - }; - - // Layout description. - static const int kValueOffset = JSObject::kHeaderSize; - static const int kYearOffset = kValueOffset + kPointerSize; - static const int kMonthOffset = kYearOffset + kPointerSize; - static const int kDayOffset = kMonthOffset + kPointerSize; - static const int kWeekdayOffset = kDayOffset + kPointerSize; - static const int kHourOffset = kWeekdayOffset + kPointerSize; - static const int kMinOffset = kHourOffset + kPointerSize; - static const int kSecOffset = kMinOffset + kPointerSize; - static const int kCacheStampOffset = kSecOffset + kPointerSize; - static const int kSize = kCacheStampOffset + kPointerSize; - - private: - inline Object* DoGetField(FieldIndex index); - - Object* GetUTCField(FieldIndex index, double value, DateCache* date_cache); - - // Computes and caches the cacheable fields of the date. - inline void SetLocalFields(int64_t local_time_ms, DateCache* date_cache); - - - DISALLOW_IMPLICIT_CONSTRUCTORS(JSDate); -}; - - -// Representation of message objects used for error reporting through -// the API. The messages are formatted in JavaScript so this object is -// a real JavaScript object. The information used for formatting the -// error messages are not directly accessible from JavaScript to -// prevent leaking information to user code called during error -// formatting. -class JSMessageObject: public JSObject { - public: - // [type]: the type of error message. - DECL_ACCESSORS(type, String) - - // [arguments]: the arguments for formatting the error message. - DECL_ACCESSORS(arguments, JSArray) - - // [script]: the script from which the error message originated. - DECL_ACCESSORS(script, Object) - - // [stack_trace]: the stack trace for this error message. - DECL_ACCESSORS(stack_trace, Object) - - // [stack_frames]: an array of stack frames for this error object. - DECL_ACCESSORS(stack_frames, Object) - - // [start_position]: the start position in the script for the error message. - inline int start_position(); - inline void set_start_position(int value); - - // [end_position]: the end position in the script for the error message. - inline int end_position(); - inline void set_end_position(int value); - - // Casting. - static inline JSMessageObject* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSMessageObject) - DECLARE_VERIFIER(JSMessageObject) - - // Layout description. - static const int kTypeOffset = JSObject::kHeaderSize; - static const int kArgumentsOffset = kTypeOffset + kPointerSize; - static const int kScriptOffset = kArgumentsOffset + kPointerSize; - static const int kStackTraceOffset = kScriptOffset + kPointerSize; - static const int kStackFramesOffset = kStackTraceOffset + kPointerSize; - static const int kStartPositionOffset = kStackFramesOffset + kPointerSize; - static const int kEndPositionOffset = kStartPositionOffset + kPointerSize; - static const int kSize = kEndPositionOffset + kPointerSize; - - typedef FixedBodyDescriptor<HeapObject::kMapOffset, - kStackFramesOffset + kPointerSize, - kSize> BodyDescriptor; -}; - - -// Regular expressions -// The regular expression holds a single reference to a FixedArray in -// the kDataOffset field. -// The FixedArray contains the following data: -// - tag : type of regexp implementation (not compiled yet, atom or irregexp) -// - reference to the original source string -// - reference to the original flag string -// If it is an atom regexp -// - a reference to a literal string to search for -// If it is an irregexp regexp: -// - a reference to code for ASCII inputs (bytecode or compiled), or a smi -// used for tracking the last usage (used for code flushing). -// - a reference to code for UC16 inputs (bytecode or compiled), or a smi -// used for tracking the last usage (used for code flushing).. -// - max number of registers used by irregexp implementations. -// - number of capture registers (output values) of the regexp. -class JSRegExp: public JSObject { - public: - // Meaning of Type: - // NOT_COMPILED: Initial value. No data has been stored in the JSRegExp yet. - // ATOM: A simple string to match against using an indexOf operation. - // IRREGEXP: Compiled with Irregexp. - // IRREGEXP_NATIVE: Compiled to native code with Irregexp. - enum Type { NOT_COMPILED, ATOM, IRREGEXP }; - enum Flag { NONE = 0, GLOBAL = 1, IGNORE_CASE = 2, MULTILINE = 4 }; - - class Flags { - public: - explicit Flags(uint32_t value) : value_(value) { } - bool is_global() { return (value_ & GLOBAL) != 0; } - bool is_ignore_case() { return (value_ & IGNORE_CASE) != 0; } - bool is_multiline() { return (value_ & MULTILINE) != 0; } - uint32_t value() { return value_; } - private: - uint32_t value_; - }; - - DECL_ACCESSORS(data, Object) - - inline Type TypeTag(); - inline int CaptureCount(); - inline Flags GetFlags(); - inline String* Pattern(); - inline Object* DataAt(int index); - // Set implementation data after the object has been prepared. - inline void SetDataAt(int index, Object* value); - - // Used during GC when flushing code or setting age. - inline Object* DataAtUnchecked(int index); - inline void SetDataAtUnchecked(int index, Object* value, Heap* heap); - inline Type TypeTagUnchecked(); - - static int code_index(bool is_ascii) { - if (is_ascii) { - return kIrregexpASCIICodeIndex; - } else { - return kIrregexpUC16CodeIndex; - } - } - - static int saved_code_index(bool is_ascii) { - if (is_ascii) { - return kIrregexpASCIICodeSavedIndex; - } else { - return kIrregexpUC16CodeSavedIndex; - } - } - - static inline JSRegExp* cast(Object* obj); - - // Dispatched behavior. - DECLARE_VERIFIER(JSRegExp) - - static const int kDataOffset = JSObject::kHeaderSize; - static const int kSize = kDataOffset + kPointerSize; - - // Indices in the data array. - static const int kTagIndex = 0; - static const int kSourceIndex = kTagIndex + 1; - static const int kFlagsIndex = kSourceIndex + 1; - static const int kDataIndex = kFlagsIndex + 1; - // The data fields are used in different ways depending on the - // value of the tag. - // Atom regexps (literal strings). - static const int kAtomPatternIndex = kDataIndex; - - static const int kAtomDataSize = kAtomPatternIndex + 1; - - // Irregexp compiled code or bytecode for ASCII. If compilation - // fails, this fields hold an exception object that should be - // thrown if the regexp is used again. - static const int kIrregexpASCIICodeIndex = kDataIndex; - // Irregexp compiled code or bytecode for UC16. If compilation - // fails, this fields hold an exception object that should be - // thrown if the regexp is used again. - static const int kIrregexpUC16CodeIndex = kDataIndex + 1; - - // Saved instance of Irregexp compiled code or bytecode for ASCII that - // is a potential candidate for flushing. - static const int kIrregexpASCIICodeSavedIndex = kDataIndex + 2; - // Saved instance of Irregexp compiled code or bytecode for UC16 that is - // a potential candidate for flushing. - static const int kIrregexpUC16CodeSavedIndex = kDataIndex + 3; - - // Maximal number of registers used by either ASCII or UC16. - // Only used to check that there is enough stack space - static const int kIrregexpMaxRegisterCountIndex = kDataIndex + 4; - // Number of captures in the compiled regexp. - static const int kIrregexpCaptureCountIndex = kDataIndex + 5; - - static const int kIrregexpDataSize = kIrregexpCaptureCountIndex + 1; - - // Offsets directly into the data fixed array. - static const int kDataTagOffset = - FixedArray::kHeaderSize + kTagIndex * kPointerSize; - static const int kDataAsciiCodeOffset = - FixedArray::kHeaderSize + kIrregexpASCIICodeIndex * kPointerSize; - static const int kDataUC16CodeOffset = - FixedArray::kHeaderSize + kIrregexpUC16CodeIndex * kPointerSize; - static const int kIrregexpCaptureCountOffset = - FixedArray::kHeaderSize + kIrregexpCaptureCountIndex * kPointerSize; - - // In-object fields. - static const int kSourceFieldIndex = 0; - static const int kGlobalFieldIndex = 1; - static const int kIgnoreCaseFieldIndex = 2; - static const int kMultilineFieldIndex = 3; - static const int kLastIndexFieldIndex = 4; - static const int kInObjectFieldCount = 5; - - // The uninitialized value for a regexp code object. - static const int kUninitializedValue = -1; - - // The compilation error value for the regexp code object. The real error - // object is in the saved code field. - static const int kCompilationErrorValue = -2; - - // When we store the sweep generation at which we moved the code from the - // code index to the saved code index we mask it of to be in the [0:255] - // range. - static const int kCodeAgeMask = 0xff; -}; - - -class CompilationCacheShape : public BaseShape<HashTableKey*> { - public: - static inline bool IsMatch(HashTableKey* key, Object* value) { - return key->IsMatch(value); - } - - static inline uint32_t Hash(HashTableKey* key) { - return key->Hash(); - } - - static inline uint32_t HashForObject(HashTableKey* key, Object* object) { - return key->HashForObject(object); - } - - MUST_USE_RESULT static MaybeObject* AsObject(HashTableKey* key) { - return key->AsObject(); - } - - static const int kPrefixSize = 0; - static const int kEntrySize = 2; -}; - - -class CompilationCacheTable: public HashTable<CompilationCacheShape, - HashTableKey*> { - public: - // Find cached value for a string key, otherwise return null. - Object* Lookup(String* src, Context* context); - Object* LookupEval(String* src, - Context* context, - LanguageMode language_mode, - int scope_position); - Object* LookupRegExp(String* source, JSRegExp::Flags flags); - MUST_USE_RESULT MaybeObject* Put(String* src, - Context* context, - Object* value); - MUST_USE_RESULT MaybeObject* PutEval(String* src, - Context* context, - SharedFunctionInfo* value, - int scope_position); - MUST_USE_RESULT MaybeObject* PutRegExp(String* src, - JSRegExp::Flags flags, - FixedArray* value); - - // Remove given value from cache. - void Remove(Object* value); - - static inline CompilationCacheTable* cast(Object* obj); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationCacheTable); -}; - - -class CodeCache: public Struct { - public: - DECL_ACCESSORS(default_cache, FixedArray) - DECL_ACCESSORS(normal_type_cache, Object) - - // Add the code object to the cache. - MUST_USE_RESULT MaybeObject* Update(String* name, Code* code); - - // Lookup code object in the cache. Returns code object if found and undefined - // if not. - Object* Lookup(String* name, Code::Flags flags); - - // Get the internal index of a code object in the cache. Returns -1 if the - // code object is not in that cache. This index can be used to later call - // RemoveByIndex. The cache cannot be modified between a call to GetIndex and - // RemoveByIndex. - int GetIndex(Object* name, Code* code); - - // Remove an object from the cache with the provided internal index. - void RemoveByIndex(Object* name, Code* code, int index); - - static inline CodeCache* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(CodeCache) - DECLARE_VERIFIER(CodeCache) - - static const int kDefaultCacheOffset = HeapObject::kHeaderSize; - static const int kNormalTypeCacheOffset = - kDefaultCacheOffset + kPointerSize; - static const int kSize = kNormalTypeCacheOffset + kPointerSize; - - private: - MUST_USE_RESULT MaybeObject* UpdateDefaultCache(String* name, Code* code); - MUST_USE_RESULT MaybeObject* UpdateNormalTypeCache(String* name, Code* code); - Object* LookupDefaultCache(String* name, Code::Flags flags); - Object* LookupNormalTypeCache(String* name, Code::Flags flags); - - // Code cache layout of the default cache. Elements are alternating name and - // code objects for non normal load/store/call IC's. - static const int kCodeCacheEntrySize = 2; - static const int kCodeCacheEntryNameOffset = 0; - static const int kCodeCacheEntryCodeOffset = 1; - - DISALLOW_IMPLICIT_CONSTRUCTORS(CodeCache); -}; - - -class CodeCacheHashTableShape : public BaseShape<HashTableKey*> { - public: - static inline bool IsMatch(HashTableKey* key, Object* value) { - return key->IsMatch(value); - } - - static inline uint32_t Hash(HashTableKey* key) { - return key->Hash(); - } - - static inline uint32_t HashForObject(HashTableKey* key, Object* object) { - return key->HashForObject(object); - } - - MUST_USE_RESULT static MaybeObject* AsObject(HashTableKey* key) { - return key->AsObject(); - } - - static const int kPrefixSize = 0; - static const int kEntrySize = 2; -}; - - -class CodeCacheHashTable: public HashTable<CodeCacheHashTableShape, - HashTableKey*> { - public: - Object* Lookup(String* name, Code::Flags flags); - MUST_USE_RESULT MaybeObject* Put(String* name, Code* code); - - int GetIndex(String* name, Code::Flags flags); - void RemoveByIndex(int index); - - static inline CodeCacheHashTable* cast(Object* obj); - - // Initial size of the fixed array backing the hash table. - static const int kInitialSize = 64; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(CodeCacheHashTable); -}; - - -class PolymorphicCodeCache: public Struct { - public: - DECL_ACCESSORS(cache, Object) - - static void Update(Handle<PolymorphicCodeCache> cache, - MapHandleList* maps, - Code::Flags flags, - Handle<Code> code); - - MUST_USE_RESULT MaybeObject* Update(MapHandleList* maps, - Code::Flags flags, - Code* code); - - // Returns an undefined value if the entry is not found. - Handle<Object> Lookup(MapHandleList* maps, Code::Flags flags); - - static inline PolymorphicCodeCache* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(PolymorphicCodeCache) - DECLARE_VERIFIER(PolymorphicCodeCache) - - static const int kCacheOffset = HeapObject::kHeaderSize; - static const int kSize = kCacheOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(PolymorphicCodeCache); -}; - - -class PolymorphicCodeCacheHashTable - : public HashTable<CodeCacheHashTableShape, HashTableKey*> { - public: - Object* Lookup(MapHandleList* maps, int code_kind); - - MUST_USE_RESULT MaybeObject* Put(MapHandleList* maps, - int code_kind, - Code* code); - - static inline PolymorphicCodeCacheHashTable* cast(Object* obj); - - static const int kInitialSize = 64; - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(PolymorphicCodeCacheHashTable); -}; - - -class TypeFeedbackInfo: public Struct { - public: - inline int ic_total_count(); - inline void set_ic_total_count(int count); - - inline int ic_with_type_info_count(); - inline void change_ic_with_type_info_count(int count); - - inline void initialize_storage(); - - inline void change_own_type_change_checksum(); - inline int own_type_change_checksum(); - - inline void set_inlined_type_change_checksum(int checksum); - inline bool matches_inlined_type_change_checksum(int checksum); - - DECL_ACCESSORS(type_feedback_cells, TypeFeedbackCells) - - static inline TypeFeedbackInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(TypeFeedbackInfo) - DECLARE_VERIFIER(TypeFeedbackInfo) - - static const int kStorage1Offset = HeapObject::kHeaderSize; - static const int kStorage2Offset = kStorage1Offset + kPointerSize; - static const int kTypeFeedbackCellsOffset = kStorage2Offset + kPointerSize; - static const int kSize = kTypeFeedbackCellsOffset + kPointerSize; - - private: - static const int kTypeChangeChecksumBits = 7; - - class ICTotalCountField: public BitField<int, 0, - kSmiValueSize - kTypeChangeChecksumBits> {}; // NOLINT - class OwnTypeChangeChecksum: public BitField<int, - kSmiValueSize - kTypeChangeChecksumBits, - kTypeChangeChecksumBits> {}; // NOLINT - class ICsWithTypeInfoCountField: public BitField<int, 0, - kSmiValueSize - kTypeChangeChecksumBits> {}; // NOLINT - class InlinedTypeChangeChecksum: public BitField<int, - kSmiValueSize - kTypeChangeChecksumBits, - kTypeChangeChecksumBits> {}; // NOLINT - - DISALLOW_IMPLICIT_CONSTRUCTORS(TypeFeedbackInfo); -}; - - -enum AllocationSiteMode { - DONT_TRACK_ALLOCATION_SITE, - TRACK_ALLOCATION_SITE, - LAST_ALLOCATION_SITE_MODE = TRACK_ALLOCATION_SITE -}; - - -class AllocationSiteInfo: public Struct { - public: - DECL_ACCESSORS(payload, Object) - - static inline AllocationSiteInfo* cast(Object* obj); - - DECLARE_PRINTER(AllocationSiteInfo) - DECLARE_VERIFIER(AllocationSiteInfo) - - // Returns NULL if no AllocationSiteInfo is available for object. - static AllocationSiteInfo* FindForJSObject(JSObject* object); - - static AllocationSiteMode GetMode(ElementsKind boilerplate_elements_kind); - static AllocationSiteMode GetMode(ElementsKind from, ElementsKind to); - - static const int kPayloadOffset = HeapObject::kHeaderSize; - static const int kSize = kPayloadOffset + kPointerSize; - static const uint32_t kMaximumArrayBytesToPretransition = 8 * 1024; - - bool GetElementsKindPayload(ElementsKind* kind); - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(AllocationSiteInfo); -}; - - -// Representation of a slow alias as part of a non-strict arguments objects. -// For fast aliases (if HasNonStrictArgumentsElements()): -// - the parameter map contains an index into the context -// - all attributes of the element have default values -// For slow aliases (if HasDictionaryArgumentsElements()): -// - the parameter map contains no fast alias mapping (i.e. the hole) -// - this struct (in the slow backing store) contains an index into the context -// - all attributes are available as part if the property details -class AliasedArgumentsEntry: public Struct { - public: - inline int aliased_context_slot(); - inline void set_aliased_context_slot(int count); - - static inline AliasedArgumentsEntry* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(AliasedArgumentsEntry) - DECLARE_VERIFIER(AliasedArgumentsEntry) - - static const int kAliasedContextSlot = HeapObject::kHeaderSize; - static const int kSize = kAliasedContextSlot + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(AliasedArgumentsEntry); -}; - - -enum AllowNullsFlag {ALLOW_NULLS, DISALLOW_NULLS}; -enum RobustnessFlag {ROBUST_STRING_TRAVERSAL, FAST_STRING_TRAVERSAL}; - - -class StringHasher { - public: - explicit inline StringHasher(int length, uint32_t seed); - - template <typename schar> - static inline uint32_t HashSequentialString(const schar* chars, - int length, - uint32_t seed); - - // Reads all the data, even for long strings and computes the utf16 length. - static uint32_t ComputeUtf8Hash(Vector<const char> chars, - uint32_t seed, - int* utf16_length_out); - - // Calculated hash value for a string consisting of 1 to - // String::kMaxArrayIndexSize digits with no leading zeros (except "0"). - // value is represented decimal value. - static uint32_t MakeArrayIndexHash(uint32_t value, int length); - - // No string is allowed to have a hash of zero. That value is reserved - // for internal properties. If the hash calculation yields zero then we - // use 27 instead. - static const int kZeroHash = 27; - - // Reusable parts of the hashing algorithm. - INLINE(static uint32_t AddCharacterCore(uint32_t running_hash, uint16_t c)); - INLINE(static uint32_t GetHashCore(uint32_t running_hash)); - - protected: - // Returns the value to store in the hash field of a string with - // the given length and contents. - uint32_t GetHashField(); - // Returns true if the hash of this string can be computed without - // looking at the contents. - inline bool has_trivial_hash(); - // Adds a block of characters to the hash. - template<typename Char> - inline void AddCharacters(const Char* chars, int len); - - private: - // Add a character to the hash. - inline void AddCharacter(uint16_t c); - // Update index. Returns true if string is still an index. - inline bool UpdateIndex(uint16_t c); - - int length_; - uint32_t raw_running_hash_; - uint32_t array_index_; - bool is_array_index_; - bool is_first_char_; - DISALLOW_COPY_AND_ASSIGN(StringHasher); -}; - - -// The characteristics of a string are stored in its map. Retrieving these -// few bits of information is moderately expensive, involving two memory -// loads where the second is dependent on the first. To improve efficiency -// the shape of the string is given its own class so that it can be retrieved -// once and used for several string operations. A StringShape is small enough -// to be passed by value and is immutable, but be aware that flattening a -// string can potentially alter its shape. Also be aware that a GC caused by -// something else can alter the shape of a string due to ConsString -// shortcutting. Keeping these restrictions in mind has proven to be error- -// prone and so we no longer put StringShapes in variables unless there is a -// concrete performance benefit at that particular point in the code. -class StringShape BASE_EMBEDDED { - public: - inline explicit StringShape(String* s); - inline explicit StringShape(Map* s); - inline explicit StringShape(InstanceType t); - inline bool IsSequential(); - inline bool IsExternal(); - inline bool IsCons(); - inline bool IsSliced(); - inline bool IsIndirect(); - inline bool IsExternalAscii(); - inline bool IsExternalTwoByte(); - inline bool IsSequentialAscii(); - inline bool IsSequentialTwoByte(); - inline bool IsInternalized(); - inline StringRepresentationTag representation_tag(); - inline uint32_t encoding_tag(); - inline uint32_t full_representation_tag(); - inline uint32_t size_tag(); -#ifdef DEBUG - inline uint32_t type() { return type_; } - inline void invalidate() { valid_ = false; } - inline bool valid() { return valid_; } -#else - inline void invalidate() { } -#endif - - private: - uint32_t type_; -#ifdef DEBUG - inline void set_valid() { valid_ = true; } - bool valid_; -#else - inline void set_valid() { } -#endif -}; - - -// The Name abstract class captures anything that can be used as a property -// name, i.e., strings and symbols. All names store a hash value. -class Name: public HeapObject { - public: - // Get and set the hash field of the name. - inline uint32_t hash_field(); - inline void set_hash_field(uint32_t value); - - // Tells whether the hash code has been computed. - inline bool HasHashCode(); - - // Returns a hash value used for the property table - inline uint32_t Hash(); - - // Casting. - static inline Name* cast(Object* obj); - - // Layout description. - static const int kHashFieldOffset = HeapObject::kHeaderSize; - static const int kSize = kHashFieldOffset + kPointerSize; - - // Mask constant for checking if a name has a computed hash code - // and if it is a string that is an array index. The least significant bit - // indicates whether a hash code has been computed. If the hash code has - // been computed the 2nd bit tells whether the string can be used as an - // array index. - static const int kHashNotComputedMask = 1; - static const int kIsNotArrayIndexMask = 1 << 1; - static const int kNofHashBitFields = 2; - - // Shift constant retrieving hash code from hash field. - static const int kHashShift = kNofHashBitFields; - - // Only these bits are relevant in the hash, since the top two are shifted - // out. - static const uint32_t kHashBitMask = 0xffffffffu >> kHashShift; - - // Array index strings this short can keep their index in the hash field. - static const int kMaxCachedArrayIndexLength = 7; - - // For strings which are array indexes the hash value has the string length - // mixed into the hash, mainly to avoid a hash value of zero which would be - // the case for the string '0'. 24 bits are used for the array index value. - static const int kArrayIndexValueBits = 24; - static const int kArrayIndexLengthBits = - kBitsPerInt - kArrayIndexValueBits - kNofHashBitFields; - - STATIC_CHECK((kArrayIndexLengthBits > 0)); - - static const int kArrayIndexHashLengthShift = - kArrayIndexValueBits + kNofHashBitFields; - - static const int kArrayIndexHashMask = (1 << kArrayIndexHashLengthShift) - 1; - - static const int kArrayIndexValueMask = - ((1 << kArrayIndexValueBits) - 1) << kHashShift; - - // Check that kMaxCachedArrayIndexLength + 1 is a power of two so we - // could use a mask to test if the length of string is less than or equal to - // kMaxCachedArrayIndexLength. - STATIC_CHECK(IS_POWER_OF_TWO(kMaxCachedArrayIndexLength + 1)); - - static const int kContainsCachedArrayIndexMask = - (~kMaxCachedArrayIndexLength << kArrayIndexHashLengthShift) | - kIsNotArrayIndexMask; - - // Value of empty hash field indicating that the hash is not computed. - static const int kEmptyHashField = - kIsNotArrayIndexMask | kHashNotComputedMask; - - protected: - static inline bool IsHashFieldComputed(uint32_t field); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(Name); -}; - - -// ES6 symbols. -class Symbol: public Name { - public: - // Casting. - static inline Symbol* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(Symbol) - DECLARE_VERIFIER(Symbol) - - // Layout description. - static const int kSize = Name::kSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(Symbol); -}; - - -// The String abstract class captures JavaScript string values: -// -// Ecma-262: -// 4.3.16 String Value -// A string value is a member of the type String and is a finite -// ordered sequence of zero or more 16-bit unsigned integer values. -// -// All string values have a length field. -class String: public Name { - public: - enum Encoding { ONE_BYTE_ENCODING, TWO_BYTE_ENCODING }; - - // Representation of the flat content of a String. - // A non-flat string doesn't have flat content. - // A flat string has content that's encoded as a sequence of either - // ASCII chars or two-byte UC16. - // Returned by String::GetFlatContent(). - class FlatContent { - public: - // Returns true if the string is flat and this structure contains content. - bool IsFlat() { return state_ != NON_FLAT; } - // Returns true if the structure contains ASCII content. - bool IsAscii() { return state_ == ASCII; } - // Returns true if the structure contains two-byte content. - bool IsTwoByte() { return state_ == TWO_BYTE; } - - // Return the one byte content of the string. Only use if IsAscii() returns - // true. - Vector<const uint8_t> ToOneByteVector() { - ASSERT_EQ(ASCII, state_); - return buffer_; - } - // Return the two-byte content of the string. Only use if IsTwoByte() - // returns true. - Vector<const uc16> ToUC16Vector() { - ASSERT_EQ(TWO_BYTE, state_); - return Vector<const uc16>::cast(buffer_); - } - - private: - enum State { NON_FLAT, ASCII, TWO_BYTE }; - - // Constructors only used by String::GetFlatContent(). - explicit FlatContent(Vector<const uint8_t> chars) - : buffer_(chars), - state_(ASCII) { } - explicit FlatContent(Vector<const uc16> chars) - : buffer_(Vector<const byte>::cast(chars)), - state_(TWO_BYTE) { } - FlatContent() : buffer_(), state_(NON_FLAT) { } - - Vector<const uint8_t> buffer_; - State state_; - - friend class String; - }; - - // Get and set the length of the string. - inline int length(); - inline void set_length(int value); - - // Returns whether this string has only ASCII chars, i.e. all of them can - // be ASCII encoded. This might be the case even if the string is - // two-byte. Such strings may appear when the embedder prefers - // two-byte external representations even for ASCII data. - inline bool IsOneByteRepresentation(); - inline bool IsTwoByteRepresentation(); - - // Cons and slices have an encoding flag that may not represent the actual - // encoding of the underlying string. This is taken into account here. - // Requires: this->IsFlat() - inline bool IsOneByteRepresentationUnderneath(); - inline bool IsTwoByteRepresentationUnderneath(); - - // NOTE: this should be considered only a hint. False negatives are - // possible. - inline bool HasOnlyAsciiChars(); - - inline bool IsOneByteConvertible(); - - // Get and set individual two byte chars in the string. - inline void Set(int index, uint16_t value); - // Get individual two byte char in the string. Repeated calls - // to this method are not efficient unless the string is flat. - INLINE(uint16_t Get(int index)); - - // Try to flatten the string. Checks first inline to see if it is - // necessary. Does nothing if the string is not a cons string. - // Flattening allocates a sequential string with the same data as - // the given string and mutates the cons string to a degenerate - // form, where the first component is the new sequential string and - // the second component is the empty string. If allocation fails, - // this function returns a failure. If flattening succeeds, this - // function returns the sequential string that is now the first - // component of the cons string. - // - // Degenerate cons strings are handled specially by the garbage - // collector (see IsShortcutCandidate). - // - // Use FlattenString from Handles.cc to flatten even in case an - // allocation failure happens. - inline MaybeObject* TryFlatten(PretenureFlag pretenure = NOT_TENURED); - - // Convenience function. Has exactly the same behavior as - // TryFlatten(), except in the case of failure returns the original - // string. - inline String* TryFlattenGetString(PretenureFlag pretenure = NOT_TENURED); - - // Tries to return the content of a flat string as a structure holding either - // a flat vector of char or of uc16. - // If the string isn't flat, and therefore doesn't have flat content, the - // returned structure will report so, and can't provide a vector of either - // kind. - FlatContent GetFlatContent(); - - // Returns the parent of a sliced string or first part of a flat cons string. - // Requires: StringShape(this).IsIndirect() && this->IsFlat() - inline String* GetUnderlying(); - - // Mark the string as an undetectable object. It only applies to - // ASCII and two byte string types. - bool MarkAsUndetectable(); - - // Return a substring. - MUST_USE_RESULT MaybeObject* SubString(int from, - int to, - PretenureFlag pretenure = NOT_TENURED); - - // String equality operations. - inline bool Equals(String* other); - bool IsUtf8EqualTo(Vector<const char> str); - bool IsOneByteEqualTo(Vector<const uint8_t> str); - bool IsTwoByteEqualTo(Vector<const uc16> str); - - // Return a UTF8 representation of the string. The string is null - // terminated but may optionally contain nulls. Length is returned - // in length_output if length_output is not a null pointer The string - // should be nearly flat, otherwise the performance of this method may - // be very slow (quadratic in the length). Setting robustness_flag to - // ROBUST_STRING_TRAVERSAL invokes behaviour that is robust This means it - // handles unexpected data without causing assert failures and it does not - // do any heap allocations. This is useful when printing stack traces. - SmartArrayPointer<char> ToCString(AllowNullsFlag allow_nulls, - RobustnessFlag robustness_flag, - int offset, - int length, - int* length_output = 0); - SmartArrayPointer<char> ToCString( - AllowNullsFlag allow_nulls = DISALLOW_NULLS, - RobustnessFlag robustness_flag = FAST_STRING_TRAVERSAL, - int* length_output = 0); - - // Return a 16 bit Unicode representation of the string. - // The string should be nearly flat, otherwise the performance of - // of this method may be very bad. Setting robustness_flag to - // ROBUST_STRING_TRAVERSAL invokes behaviour that is robust This means it - // handles unexpected data without causing assert failures and it does not - // do any heap allocations. This is useful when printing stack traces. - SmartArrayPointer<uc16> ToWideCString( - RobustnessFlag robustness_flag = FAST_STRING_TRAVERSAL); - - bool ComputeArrayIndex(uint32_t* index); - - // Externalization. - bool MakeExternal(v8::String::ExternalStringResource* resource); - bool MakeExternal(v8::String::ExternalAsciiStringResource* resource); - - // Conversion. - inline bool AsArrayIndex(uint32_t* index); - - // Casting. - static inline String* cast(Object* obj); - - void PrintOn(FILE* out); - - // For use during stack traces. Performs rudimentary sanity check. - bool LooksValid(); - - // Dispatched behavior. - void StringShortPrint(StringStream* accumulator); -#ifdef OBJECT_PRINT - inline void StringPrint() { - StringPrint(stdout); - } - void StringPrint(FILE* out); - - char* ToAsciiArray(); -#endif - DECLARE_VERIFIER(String) - - inline bool IsFlat(); - - // Layout description. - static const int kLengthOffset = Name::kSize; - static const int kSize = kLengthOffset + kPointerSize; - - // Maximum number of characters to consider when trying to convert a string - // value into an array index. - static const int kMaxArrayIndexSize = 10; - STATIC_CHECK(kMaxArrayIndexSize < (1 << kArrayIndexLengthBits)); - - // Max char codes. - static const int32_t kMaxOneByteCharCode = unibrow::Latin1::kMaxChar; - static const uint32_t kMaxOneByteCharCodeU = unibrow::Latin1::kMaxChar; - static const int kMaxUtf16CodeUnit = 0xffff; - - // Value of hash field containing computed hash equal to zero. - static const int kEmptyStringHash = kIsNotArrayIndexMask; - - // Maximal string length. - static const int kMaxLength = (1 << (32 - 2)) - 1; - - // Max length for computing hash. For strings longer than this limit the - // string length is used as the hash value. - static const int kMaxHashCalcLength = 16383; - - // Limit for truncation in short printing. - static const int kMaxShortPrintLength = 1024; - - // Support for regular expressions. - const uc16* GetTwoByteData(); - const uc16* GetTwoByteData(unsigned start); - - // Helper function for flattening strings. - template <typename sinkchar> - static void WriteToFlat(String* source, - sinkchar* sink, - int from, - int to); - - // The return value may point to the first aligned word containing the - // first non-ascii character, rather than directly to the non-ascii character. - // If the return value is >= the passed length, the entire string was ASCII. - static inline int NonAsciiStart(const char* chars, int length) { - const char* start = chars; - const char* limit = chars + length; -#ifdef V8_HOST_CAN_READ_UNALIGNED - ASSERT(unibrow::Utf8::kMaxOneByteChar == 0x7F); - const uintptr_t non_ascii_mask = kUintptrAllBitsSet / 0xFF * 0x80; - while (chars + sizeof(uintptr_t) <= limit) { - if (*reinterpret_cast<const uintptr_t*>(chars) & non_ascii_mask) { - return static_cast<int>(chars - start); - } - chars += sizeof(uintptr_t); - } -#endif - while (chars < limit) { - if (static_cast<uint8_t>(*chars) > unibrow::Utf8::kMaxOneByteChar) { - return static_cast<int>(chars - start); - } - ++chars; - } - return static_cast<int>(chars - start); - } - - static inline bool IsAscii(const char* chars, int length) { - return NonAsciiStart(chars, length) >= length; - } - - static inline bool IsAscii(const uint8_t* chars, int length) { - return - NonAsciiStart(reinterpret_cast<const char*>(chars), length) >= length; - } - - static inline int NonOneByteStart(const uc16* chars, int length) { - const uc16* limit = chars + length; - const uc16* start = chars; - while (chars < limit) { - if (*chars > kMaxOneByteCharCodeU) return static_cast<int>(chars - start); - ++chars; - } - return static_cast<int>(chars - start); - } - - static inline bool IsOneByte(const uc16* chars, int length) { - return NonOneByteStart(chars, length) >= length; - } - - template<class Visitor, class ConsOp> - static inline void Visit(String* string, - unsigned offset, - Visitor& visitor, - ConsOp& cons_op, - int32_t type, - unsigned length); - - private: - friend class Name; - - // Try to flatten the top level ConsString that is hiding behind this - // string. This is a no-op unless the string is a ConsString. Flatten - // mutates the ConsString and might return a failure. - MUST_USE_RESULT MaybeObject* SlowTryFlatten(PretenureFlag pretenure); - - // Slow case of String::Equals. This implementation works on any strings - // but it is most efficient on strings that are almost flat. - bool SlowEquals(String* other); - - // Slow case of AsArrayIndex. - bool SlowAsArrayIndex(uint32_t* index); - - // Compute and set the hash code. - uint32_t ComputeAndSetHash(); - - DISALLOW_IMPLICIT_CONSTRUCTORS(String); -}; - - -// The SeqString abstract class captures sequential string values. -class SeqString: public String { - public: - // Casting. - static inline SeqString* cast(Object* obj); - - // Get and set the symbol id of the string - inline int symbol_id(); - inline void set_symbol_id(int value); - - // Layout description. - static const int kSymbolIdOffset = String::kSize; - static const int kHeaderSize = kSymbolIdOffset + kPointerSize; - - // Truncate the string in-place if possible and return the result. - // In case of new_length == 0, the empty string is returned without - // truncating the original string. - MUST_USE_RESULT String* Truncate(int new_length); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(SeqString); -}; - - -// The AsciiString class captures sequential ASCII string objects. -// Each character in the AsciiString is an ASCII character. -class SeqOneByteString: public SeqString { - public: - static const bool kHasAsciiEncoding = true; - - // Dispatched behavior. - inline uint16_t SeqOneByteStringGet(int index); - inline void SeqOneByteStringSet(int index, uint16_t value); - - // Get the address of the characters in this string. - inline Address GetCharsAddress(); - - inline uint8_t* GetChars(); - - // Casting - static inline SeqOneByteString* cast(Object* obj); - - // Garbage collection support. This method is called by the - // garbage collector to compute the actual size of an AsciiString - // instance. - inline int SeqOneByteStringSize(InstanceType instance_type); - - // Computes the size for an AsciiString instance of a given length. - static int SizeFor(int length) { - return OBJECT_POINTER_ALIGN(kHeaderSize + length * kCharSize); - } - - // Maximal memory usage for a single sequential ASCII string. - static const int kMaxSize = 512 * MB - 1; - // Maximal length of a single sequential ASCII string. - // Q.v. String::kMaxLength which is the maximal size of concatenated strings. - static const int kMaxLength = (kMaxSize - kHeaderSize); - - DECLARE_VERIFIER(SeqOneByteString) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(SeqOneByteString); -}; - - -// The TwoByteString class captures sequential unicode string objects. -// Each character in the TwoByteString is a two-byte uint16_t. -class SeqTwoByteString: public SeqString { - public: - static const bool kHasAsciiEncoding = false; - - // Dispatched behavior. - inline uint16_t SeqTwoByteStringGet(int index); - inline void SeqTwoByteStringSet(int index, uint16_t value); - - // Get the address of the characters in this string. - inline Address GetCharsAddress(); - - inline uc16* GetChars(); - - // For regexp code. - const uint16_t* SeqTwoByteStringGetData(unsigned start); - - // Casting - static inline SeqTwoByteString* cast(Object* obj); - - // Garbage collection support. This method is called by the - // garbage collector to compute the actual size of a TwoByteString - // instance. - inline int SeqTwoByteStringSize(InstanceType instance_type); - - // Computes the size for a TwoByteString instance of a given length. - static int SizeFor(int length) { - return OBJECT_POINTER_ALIGN(kHeaderSize + length * kShortSize); - } - - // Maximal memory usage for a single sequential two-byte string. - static const int kMaxSize = 512 * MB - 1; - // Maximal length of a single sequential two-byte string. - // Q.v. String::kMaxLength which is the maximal size of concatenated strings. - static const int kMaxLength = (kMaxSize - kHeaderSize) / sizeof(uint16_t); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(SeqTwoByteString); -}; - - -// The ConsString class describes string values built by using the -// addition operator on strings. A ConsString is a pair where the -// first and second components are pointers to other string values. -// One or both components of a ConsString can be pointers to other -// ConsStrings, creating a binary tree of ConsStrings where the leaves -// are non-ConsString string values. The string value represented by -// a ConsString can be obtained by concatenating the leaf string -// values in a left-to-right depth-first traversal of the tree. -class ConsString: public String { - public: - // First string of the cons cell. - inline String* first(); - // Doesn't check that the result is a string, even in debug mode. This is - // useful during GC where the mark bits confuse the checks. - inline Object* unchecked_first(); - inline void set_first(String* first, - WriteBarrierMode mode = UPDATE_WRITE_BARRIER); - - // Second string of the cons cell. - inline String* second(); - // Doesn't check that the result is a string, even in debug mode. This is - // useful during GC where the mark bits confuse the checks. - inline Object* unchecked_second(); - inline void set_second(String* second, - WriteBarrierMode mode = UPDATE_WRITE_BARRIER); - - // Dispatched behavior. - uint16_t ConsStringGet(int index); - - // Casting. - static inline ConsString* cast(Object* obj); - - // Layout description. - static const int kFirstOffset = POINTER_SIZE_ALIGN(String::kSize); - static const int kSecondOffset = kFirstOffset + kPointerSize; - static const int kSize = kSecondOffset + kPointerSize; - - // Minimum length for a cons string. - static const int kMinLength = 13; - - typedef FixedBodyDescriptor<kFirstOffset, kSecondOffset + kPointerSize, kSize> - BodyDescriptor; - - DECLARE_VERIFIER(ConsString) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ConsString); -}; - - -// The Sliced String class describes strings that are substrings of another -// sequential string. The motivation is to save time and memory when creating -// a substring. A Sliced String is described as a pointer to the parent, -// the offset from the start of the parent string and the length. Using -// a Sliced String therefore requires unpacking of the parent string and -// adding the offset to the start address. A substring of a Sliced String -// are not nested since the double indirection is simplified when creating -// such a substring. -// Currently missing features are: -// - handling externalized parent strings -// - external strings as parent -// - truncating sliced string to enable otherwise unneeded parent to be GC'ed. -class SlicedString: public String { - public: - inline String* parent(); - inline void set_parent(String* parent, - WriteBarrierMode mode = UPDATE_WRITE_BARRIER); - inline int offset(); - inline void set_offset(int offset); - - // Dispatched behavior. - uint16_t SlicedStringGet(int index); - - // Casting. - static inline SlicedString* cast(Object* obj); - - // Layout description. - static const int kParentOffset = POINTER_SIZE_ALIGN(String::kSize); - static const int kOffsetOffset = kParentOffset + kPointerSize; - static const int kSize = kOffsetOffset + kPointerSize; - - // Minimum length for a sliced string. - static const int kMinLength = 13; - - typedef FixedBodyDescriptor<kParentOffset, - kOffsetOffset + kPointerSize, kSize> - BodyDescriptor; - - DECLARE_VERIFIER(SlicedString) - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(SlicedString); -}; - - -// The ExternalString class describes string values that are backed by -// a string resource that lies outside the V8 heap. ExternalStrings -// consist of the length field common to all strings, a pointer to the -// external resource. It is important to ensure (externally) that the -// resource is not deallocated while the ExternalString is live in the -// V8 heap. -// -// The API expects that all ExternalStrings are created through the -// API. Therefore, ExternalStrings should not be used internally. -class ExternalString: public String { - public: - // Casting - static inline ExternalString* cast(Object* obj); - - // Layout description. - static const int kResourceOffset = POINTER_SIZE_ALIGN(String::kSize); - static const int kShortSize = kResourceOffset + kPointerSize; - static const int kResourceDataOffset = kResourceOffset + kPointerSize; - static const int kSize = kResourceDataOffset + kPointerSize; - - static const int kMaxShortLength = - (kShortSize - SeqString::kHeaderSize) / kCharSize; - - // Return whether external string is short (data pointer is not cached). - inline bool is_short(); - - STATIC_CHECK(kResourceOffset == Internals::kStringResourceOffset); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalString); -}; - - -// The ExternalAsciiString class is an external string backed by an -// ASCII string. -class ExternalAsciiString: public ExternalString { - public: - static const bool kHasAsciiEncoding = true; - - typedef v8::String::ExternalAsciiStringResource Resource; - - // The underlying resource. - inline const Resource* resource(); - inline void set_resource(const Resource* buffer); - - // Update the pointer cache to the external character array. - // The cached pointer is always valid, as the external character array does = - // not move during lifetime. Deserialization is the only exception, after - // which the pointer cache has to be refreshed. - inline void update_data_cache(); - - inline const uint8_t* GetChars(); - - // Dispatched behavior. - inline uint16_t ExternalAsciiStringGet(int index); - - // Casting. - static inline ExternalAsciiString* cast(Object* obj); - - // Garbage collection support. - inline void ExternalAsciiStringIterateBody(ObjectVisitor* v); - - template<typename StaticVisitor> - inline void ExternalAsciiStringIterateBody(); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalAsciiString); -}; - - -// The ExternalTwoByteString class is an external string backed by a UTF-16 -// encoded string. -class ExternalTwoByteString: public ExternalString { - public: - static const bool kHasAsciiEncoding = false; - - typedef v8::String::ExternalStringResource Resource; - - // The underlying string resource. - inline const Resource* resource(); - inline void set_resource(const Resource* buffer); - - // Update the pointer cache to the external character array. - // The cached pointer is always valid, as the external character array does = - // not move during lifetime. Deserialization is the only exception, after - // which the pointer cache has to be refreshed. - inline void update_data_cache(); - - inline const uint16_t* GetChars(); - - // Dispatched behavior. - inline uint16_t ExternalTwoByteStringGet(int index); - - // For regexp code. - inline const uint16_t* ExternalTwoByteStringGetData(unsigned start); - - // Casting. - static inline ExternalTwoByteString* cast(Object* obj); - - // Garbage collection support. - inline void ExternalTwoByteStringIterateBody(ObjectVisitor* v); - - template<typename StaticVisitor> - inline void ExternalTwoByteStringIterateBody(); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExternalTwoByteString); -}; - - -// Utility superclass for stack-allocated objects that must be updated -// on gc. It provides two ways for the gc to update instances, either -// iterating or updating after gc. -class Relocatable BASE_EMBEDDED { - public: - explicit inline Relocatable(Isolate* isolate); - inline virtual ~Relocatable(); - virtual void IterateInstance(ObjectVisitor* v) { } - virtual void PostGarbageCollection() { } - - static void PostGarbageCollectionProcessing(); - static int ArchiveSpacePerThread(); - static char* ArchiveState(Isolate* isolate, char* to); - static char* RestoreState(Isolate* isolate, char* from); - static void Iterate(ObjectVisitor* v); - static void Iterate(ObjectVisitor* v, Relocatable* top); - static char* Iterate(ObjectVisitor* v, char* t); - private: - Isolate* isolate_; - Relocatable* prev_; -}; - - -// A flat string reader provides random access to the contents of a -// string independent of the character width of the string. The handle -// must be valid as long as the reader is being used. -class FlatStringReader : public Relocatable { - public: - FlatStringReader(Isolate* isolate, Handle<String> str); - FlatStringReader(Isolate* isolate, Vector<const char> input); - void PostGarbageCollection(); - inline uc32 Get(int index); - int length() { return length_; } - private: - String** str_; - bool is_ascii_; - int length_; - const void* start_; -}; - - -// A ConsStringOp that returns null. -// Useful when the operation to apply on a ConsString -// requires an expensive data structure. -class ConsStringNullOp { - public: - inline ConsStringNullOp() {} - static inline String* Operate(String*, unsigned*, int32_t*, unsigned*); - private: - DISALLOW_COPY_AND_ASSIGN(ConsStringNullOp); -}; - - -// This maintains an off-stack representation of the stack frames required -// to traverse a ConsString, allowing an entirely iterative and restartable -// traversal of the entire string -// Note: this class is not GC-safe. -class ConsStringIteratorOp { - public: - inline ConsStringIteratorOp() {} - String* Operate(String* string, - unsigned* offset_out, - int32_t* type_out, - unsigned* length_out); - inline String* ContinueOperation(int32_t* type_out, unsigned* length_out); - inline void Reset(); - inline bool HasMore(); - - private: - // TODO(dcarney): Templatize this out for different stack sizes. - static const unsigned kStackSize = 32; - // Use a mask instead of doing modulo operations for stack wrapping. - static const unsigned kDepthMask = kStackSize-1; - STATIC_ASSERT(IS_POWER_OF_TWO(kStackSize)); - static inline unsigned OffsetForDepth(unsigned depth); - - inline void PushLeft(ConsString* string); - inline void PushRight(ConsString* string); - inline void AdjustMaximumDepth(); - inline void Pop(); - String* NextLeaf(bool* blew_stack, int32_t* type_out, unsigned* length_out); - String* Search(unsigned* offset_out, - int32_t* type_out, - unsigned* length_out); - - unsigned depth_; - unsigned maximum_depth_; - // Stack must always contain only frames for which right traversal - // has not yet been performed. - ConsString* frames_[kStackSize]; - unsigned consumed_; - ConsString* root_; - DISALLOW_COPY_AND_ASSIGN(ConsStringIteratorOp); -}; - - -// Note: this class is not GC-safe. -class StringCharacterStream { - public: - inline StringCharacterStream(String* string, - ConsStringIteratorOp* op, - unsigned offset = 0); - inline uint16_t GetNext(); - inline bool HasMore(); - inline void Reset(String* string, unsigned offset = 0); - inline void VisitOneByteString(const uint8_t* chars, unsigned length); - inline void VisitTwoByteString(const uint16_t* chars, unsigned length); - - private: - bool is_one_byte_; - union { - const uint8_t* buffer8_; - const uint16_t* buffer16_; - }; - const uint8_t* end_; - ConsStringIteratorOp* op_; - DISALLOW_COPY_AND_ASSIGN(StringCharacterStream); -}; - - -template <typename T> -class VectorIterator { - public: - VectorIterator(T* d, int l) : data_(Vector<const T>(d, l)), index_(0) { } - explicit VectorIterator(Vector<const T> data) : data_(data), index_(0) { } - T GetNext() { return data_[index_++]; } - bool has_more() { return index_ < data_.length(); } - private: - Vector<const T> data_; - int index_; -}; - - -// The Oddball describes objects null, undefined, true, and false. -class Oddball: public HeapObject { - public: - // [to_string]: Cached to_string computed at startup. - DECL_ACCESSORS(to_string, String) - - // [to_number]: Cached to_number computed at startup. - DECL_ACCESSORS(to_number, Object) - - inline byte kind(); - inline void set_kind(byte kind); - - // Casting. - static inline Oddball* cast(Object* obj); - - // Dispatched behavior. - DECLARE_VERIFIER(Oddball) - - // Initialize the fields. - MUST_USE_RESULT MaybeObject* Initialize(const char* to_string, - Object* to_number, - byte kind); - - // Layout description. - static const int kToStringOffset = HeapObject::kHeaderSize; - static const int kToNumberOffset = kToStringOffset + kPointerSize; - static const int kKindOffset = kToNumberOffset + kPointerSize; - static const int kSize = kKindOffset + kPointerSize; - - static const byte kFalse = 0; - static const byte kTrue = 1; - static const byte kNotBooleanMask = ~1; - static const byte kTheHole = 2; - static const byte kNull = 3; - static const byte kArgumentMarker = 4; - static const byte kUndefined = 5; - static const byte kOther = 6; - - typedef FixedBodyDescriptor<kToStringOffset, - kToNumberOffset + kPointerSize, - kSize> BodyDescriptor; - - STATIC_CHECK(kKindOffset == Internals::kOddballKindOffset); - STATIC_CHECK(kNull == Internals::kNullOddballKind); - STATIC_CHECK(kUndefined == Internals::kUndefinedOddballKind); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(Oddball); -}; - - -class JSGlobalPropertyCell: public HeapObject { - public: - // [value]: value of the global property. - DECL_ACCESSORS(value, Object) - - // Casting. - static inline JSGlobalPropertyCell* cast(Object* obj); - - static inline JSGlobalPropertyCell* FromValueAddress(Address value) { - return cast(FromAddress(value - kValueOffset)); - } - - inline Address ValueAddress() { - return address() + kValueOffset; - } - - // Dispatched behavior. - DECLARE_PRINTER(JSGlobalPropertyCell) - DECLARE_VERIFIER(JSGlobalPropertyCell) - - // Layout description. - static const int kValueOffset = HeapObject::kHeaderSize; - static const int kSize = kValueOffset + kPointerSize; - - typedef FixedBodyDescriptor<kValueOffset, - kValueOffset + kPointerSize, - kSize> BodyDescriptor; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSGlobalPropertyCell); -}; - - -// The JSProxy describes EcmaScript Harmony proxies -class JSProxy: public JSReceiver { - public: - // [handler]: The handler property. - DECL_ACCESSORS(handler, Object) - - // [hash]: The hash code property (undefined if not initialized yet). - DECL_ACCESSORS(hash, Object) - - // Casting. - static inline JSProxy* cast(Object* obj); - - bool HasPropertyWithHandler(String* name); - bool HasElementWithHandler(uint32_t index); - - MUST_USE_RESULT MaybeObject* GetPropertyWithHandler( - Object* receiver, - String* name); - MUST_USE_RESULT MaybeObject* GetElementWithHandler( - Object* receiver, - uint32_t index); - - MUST_USE_RESULT MaybeObject* SetPropertyWithHandler( - JSReceiver* receiver, - String* name, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode); - MUST_USE_RESULT MaybeObject* SetElementWithHandler( - JSReceiver* receiver, - uint32_t index, - Object* value, - StrictModeFlag strict_mode); - - // If the handler defines an accessor property with a setter, invoke it. - // If it defines an accessor property without a setter, or a data property - // that is read-only, throw. In all these cases set '*done' to true, - // otherwise set it to false. - MUST_USE_RESULT MaybeObject* SetPropertyViaPrototypesWithHandler( - JSReceiver* receiver, - String* name, - Object* value, - PropertyAttributes attributes, - StrictModeFlag strict_mode, - bool* done); - - MUST_USE_RESULT MaybeObject* DeletePropertyWithHandler( - String* name, - DeleteMode mode); - MUST_USE_RESULT MaybeObject* DeleteElementWithHandler( - uint32_t index, - DeleteMode mode); - - MUST_USE_RESULT PropertyAttributes GetPropertyAttributeWithHandler( - JSReceiver* receiver, - String* name); - MUST_USE_RESULT PropertyAttributes GetElementAttributeWithHandler( - JSReceiver* receiver, - uint32_t index); - - MUST_USE_RESULT MaybeObject* GetIdentityHash(CreationFlag flag); - - // Turn this into an (empty) JSObject. - void Fix(); - - // Initializes the body after the handler slot. - inline void InitializeBody(int object_size, Object* value); - - // Invoke a trap by name. If the trap does not exist on this's handler, - // but derived_trap is non-NULL, invoke that instead. May cause GC. - Handle<Object> CallTrap(const char* name, - Handle<Object> derived_trap, - int argc, - Handle<Object> args[]); - - // Dispatched behavior. - DECLARE_PRINTER(JSProxy) - DECLARE_VERIFIER(JSProxy) - - // Layout description. We add padding so that a proxy has the same - // size as a virgin JSObject. This is essential for becoming a JSObject - // upon freeze. - static const int kHandlerOffset = HeapObject::kHeaderSize; - static const int kHashOffset = kHandlerOffset + kPointerSize; - static const int kPaddingOffset = kHashOffset + kPointerSize; - static const int kSize = JSObject::kHeaderSize; - static const int kHeaderSize = kPaddingOffset; - static const int kPaddingSize = kSize - kPaddingOffset; - - STATIC_CHECK(kPaddingSize >= 0); - - typedef FixedBodyDescriptor<kHandlerOffset, - kPaddingOffset, - kSize> BodyDescriptor; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSProxy); -}; - - -class JSFunctionProxy: public JSProxy { - public: - // [call_trap]: The call trap. - DECL_ACCESSORS(call_trap, Object) - - // [construct_trap]: The construct trap. - DECL_ACCESSORS(construct_trap, Object) - - // Casting. - static inline JSFunctionProxy* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSFunctionProxy) - DECLARE_VERIFIER(JSFunctionProxy) - - // Layout description. - static const int kCallTrapOffset = JSProxy::kPaddingOffset; - static const int kConstructTrapOffset = kCallTrapOffset + kPointerSize; - static const int kPaddingOffset = kConstructTrapOffset + kPointerSize; - static const int kSize = JSFunction::kSize; - static const int kPaddingSize = kSize - kPaddingOffset; - - STATIC_CHECK(kPaddingSize >= 0); - - typedef FixedBodyDescriptor<kHandlerOffset, - kConstructTrapOffset + kPointerSize, - kSize> BodyDescriptor; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSFunctionProxy); -}; - - -// The JSSet describes EcmaScript Harmony sets -class JSSet: public JSObject { - public: - // [set]: the backing hash set containing keys. - DECL_ACCESSORS(table, Object) - - // Casting. - static inline JSSet* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSSet) - DECLARE_VERIFIER(JSSet) - - static const int kTableOffset = JSObject::kHeaderSize; - static const int kSize = kTableOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSSet); -}; - - -// The JSMap describes EcmaScript Harmony maps -class JSMap: public JSObject { - public: - // [table]: the backing hash table mapping keys to values. - DECL_ACCESSORS(table, Object) - - // Casting. - static inline JSMap* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSMap) - DECLARE_VERIFIER(JSMap) - - static const int kTableOffset = JSObject::kHeaderSize; - static const int kSize = kTableOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSMap); -}; - - -// The JSWeakMap describes EcmaScript Harmony weak maps -class JSWeakMap: public JSObject { - public: - // [table]: the backing hash table mapping keys to values. - DECL_ACCESSORS(table, Object) - - // [next]: linked list of encountered weak maps during GC. - DECL_ACCESSORS(next, Object) - - // Casting. - static inline JSWeakMap* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(JSWeakMap) - DECLARE_VERIFIER(JSWeakMap) - - static const int kTableOffset = JSObject::kHeaderSize; - static const int kNextOffset = kTableOffset + kPointerSize; - static const int kSize = kNextOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSWeakMap); -}; - - -// Foreign describes objects pointing from JavaScript to C structures. -// Since they cannot contain references to JS HeapObjects they can be -// placed in old_data_space. -class Foreign: public HeapObject { - public: - // [address]: field containing the address. - inline Address foreign_address(); - inline void set_foreign_address(Address value); - - // Casting. - static inline Foreign* cast(Object* obj); - - // Dispatched behavior. - inline void ForeignIterateBody(ObjectVisitor* v); - - template<typename StaticVisitor> - inline void ForeignIterateBody(); - - // Dispatched behavior. - DECLARE_PRINTER(Foreign) - DECLARE_VERIFIER(Foreign) - - // Layout description. - - static const int kForeignAddressOffset = HeapObject::kHeaderSize; - static const int kSize = kForeignAddressOffset + kPointerSize; - - STATIC_CHECK(kForeignAddressOffset == Internals::kForeignAddressOffset); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(Foreign); -}; - - -// The JSArray describes JavaScript Arrays -// Such an array can be in one of two modes: -// - fast, backing storage is a FixedArray and length <= elements.length(); -// Please note: push and pop can be used to grow and shrink the array. -// - slow, backing storage is a HashTable with numbers as keys. -class JSArray: public JSObject { - public: - // [length]: The length property. - DECL_ACCESSORS(length, Object) - - // Overload the length setter to skip write barrier when the length - // is set to a smi. This matches the set function on FixedArray. - inline void set_length(Smi* length); - - MUST_USE_RESULT MaybeObject* JSArrayUpdateLengthFromIndex(uint32_t index, - Object* value); - - // Initialize the array with the given capacity. The function may - // fail due to out-of-memory situations, but only if the requested - // capacity is non-zero. - MUST_USE_RESULT MaybeObject* Initialize(int capacity, int length = 0); - - // Initializes the array to a certain length. - inline bool AllowsSetElementsLength(); - // Can cause GC. - MUST_USE_RESULT MaybeObject* SetElementsLength(Object* length); - - // Set the content of the array to the content of storage. - MUST_USE_RESULT inline MaybeObject* SetContent(FixedArrayBase* storage); - - // Casting. - static inline JSArray* cast(Object* obj); - - // Uses handles. Ensures that the fixed array backing the JSArray has at - // least the stated size. - inline void EnsureSize(int minimum_size_of_backing_fixed_array); - - // Dispatched behavior. - DECLARE_PRINTER(JSArray) - DECLARE_VERIFIER(JSArray) - - // Number of element slots to pre-allocate for an empty array. - static const int kPreallocatedArrayElements = 4; - - // Layout description. - static const int kLengthOffset = JSObject::kHeaderSize; - static const int kSize = kLengthOffset + kPointerSize; - - private: - // Expand the fixed array backing of a fast-case JSArray to at least - // the requested size. - void Expand(int minimum_size_of_backing_fixed_array); - - DISALLOW_IMPLICIT_CONSTRUCTORS(JSArray); -}; - - -// JSRegExpResult is just a JSArray with a specific initial map. -// This initial map adds in-object properties for "index" and "input" -// properties, as assigned by RegExp.prototype.exec, which allows -// faster creation of RegExp exec results. -// This class just holds constants used when creating the result. -// After creation the result must be treated as a JSArray in all regards. -class JSRegExpResult: public JSArray { - public: - // Offsets of object fields. - static const int kIndexOffset = JSArray::kSize; - static const int kInputOffset = kIndexOffset + kPointerSize; - static const int kSize = kInputOffset + kPointerSize; - // Indices of in-object properties. - static const int kIndexIndex = 0; - static const int kInputIndex = 1; - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(JSRegExpResult); -}; - - -class AccessorInfo: public Struct { - public: - DECL_ACCESSORS(name, Object) - DECL_ACCESSORS(flag, Smi) - DECL_ACCESSORS(expected_receiver_type, Object) - - inline bool all_can_read(); - inline void set_all_can_read(bool value); - - inline bool all_can_write(); - inline void set_all_can_write(bool value); - - inline bool prohibits_overwriting(); - inline void set_prohibits_overwriting(bool value); - - inline PropertyAttributes property_attributes(); - inline void set_property_attributes(PropertyAttributes attributes); - - // Checks whether the given receiver is compatible with this accessor. - inline bool IsCompatibleReceiver(Object* receiver); - - static inline AccessorInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_VERIFIER(AccessorInfo) - - - static const int kNameOffset = HeapObject::kHeaderSize; - static const int kFlagOffset = kNameOffset + kPointerSize; - static const int kExpectedReceiverTypeOffset = kFlagOffset + kPointerSize; - static const int kSize = kExpectedReceiverTypeOffset + kPointerSize; - - private: - // Bit positions in flag. - static const int kAllCanReadBit = 0; - static const int kAllCanWriteBit = 1; - static const int kProhibitsOverwritingBit = 2; - class AttributesField: public BitField<PropertyAttributes, 3, 3> {}; - - DISALLOW_IMPLICIT_CONSTRUCTORS(AccessorInfo); -}; - - -class DeclaredAccessorDescriptor: public Struct { - public: - // TODO(dcarney): Fill out this class. - DECL_ACCESSORS(internal_field, Smi) - - static inline DeclaredAccessorDescriptor* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(DeclaredAccessorDescriptor) - DECLARE_VERIFIER(DeclaredAccessorDescriptor) - - static const int kInternalFieldOffset = HeapObject::kHeaderSize; - static const int kSize = kInternalFieldOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(DeclaredAccessorDescriptor); -}; - - -class DeclaredAccessorInfo: public AccessorInfo { - public: - DECL_ACCESSORS(descriptor, DeclaredAccessorDescriptor) - - static inline DeclaredAccessorInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(DeclaredAccessorInfo) - DECLARE_VERIFIER(DeclaredAccessorInfo) - - static const int kDescriptorOffset = AccessorInfo::kSize; - static const int kSize = kDescriptorOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(DeclaredAccessorInfo); -}; - - -// An accessor must have a getter, but can have no setter. -// -// When setting a property, V8 searches accessors in prototypes. -// If an accessor was found and it does not have a setter, -// the request is ignored. -// -// If the accessor in the prototype has the READ_ONLY property attribute, then -// a new value is added to the local object when the property is set. -// This shadows the accessor in the prototype. -class ExecutableAccessorInfo: public AccessorInfo { - public: - DECL_ACCESSORS(getter, Object) - DECL_ACCESSORS(setter, Object) - DECL_ACCESSORS(data, Object) - - static inline ExecutableAccessorInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ExecutableAccessorInfo) - DECLARE_VERIFIER(ExecutableAccessorInfo) - - static const int kGetterOffset = AccessorInfo::kSize; - static const int kSetterOffset = kGetterOffset + kPointerSize; - static const int kDataOffset = kSetterOffset + kPointerSize; - static const int kSize = kDataOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(ExecutableAccessorInfo); -}; - - -// Support for JavaScript accessors: A pair of a getter and a setter. Each -// accessor can either be -// * a pointer to a JavaScript function or proxy: a real accessor -// * undefined: considered an accessor by the spec, too, strangely enough -// * the hole: an accessor which has not been set -// * a pointer to a map: a transition used to ensure map sharing -class AccessorPair: public Struct { - public: - DECL_ACCESSORS(getter, Object) - DECL_ACCESSORS(setter, Object) - - static inline AccessorPair* cast(Object* obj); - - MUST_USE_RESULT MaybeObject* Copy(); - - Object* get(AccessorComponent component) { - return component == ACCESSOR_GETTER ? getter() : setter(); - } - - void set(AccessorComponent component, Object* value) { - if (component == ACCESSOR_GETTER) { - set_getter(value); - } else { - set_setter(value); - } - } - - // Note: Returns undefined instead in case of a hole. - Object* GetComponent(AccessorComponent component); - - // Set both components, skipping arguments which are a JavaScript null. - void SetComponents(Object* getter, Object* setter) { - if (!getter->IsNull()) set_getter(getter); - if (!setter->IsNull()) set_setter(setter); - } - - bool ContainsAccessor() { - return IsJSAccessor(getter()) || IsJSAccessor(setter()); - } - - // Dispatched behavior. - DECLARE_PRINTER(AccessorPair) - DECLARE_VERIFIER(AccessorPair) - - static const int kGetterOffset = HeapObject::kHeaderSize; - static const int kSetterOffset = kGetterOffset + kPointerSize; - static const int kSize = kSetterOffset + kPointerSize; - - private: - // Strangely enough, in addition to functions and harmony proxies, the spec - // requires us to consider undefined as a kind of accessor, too: - // var obj = {}; - // Object.defineProperty(obj, "foo", {get: undefined}); - // assertTrue("foo" in obj); - bool IsJSAccessor(Object* obj) { - return obj->IsSpecFunction() || obj->IsUndefined(); - } - - DISALLOW_IMPLICIT_CONSTRUCTORS(AccessorPair); -}; - - -class AccessCheckInfo: public Struct { - public: - DECL_ACCESSORS(named_callback, Object) - DECL_ACCESSORS(indexed_callback, Object) - DECL_ACCESSORS(data, Object) - - static inline AccessCheckInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(AccessCheckInfo) - DECLARE_VERIFIER(AccessCheckInfo) - - static const int kNamedCallbackOffset = HeapObject::kHeaderSize; - static const int kIndexedCallbackOffset = kNamedCallbackOffset + kPointerSize; - static const int kDataOffset = kIndexedCallbackOffset + kPointerSize; - static const int kSize = kDataOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(AccessCheckInfo); -}; - - -class InterceptorInfo: public Struct { - public: - DECL_ACCESSORS(getter, Object) - DECL_ACCESSORS(setter, Object) - DECL_ACCESSORS(query, Object) - DECL_ACCESSORS(deleter, Object) - DECL_ACCESSORS(enumerator, Object) - DECL_ACCESSORS(data, Object) - DECL_ACCESSORS(is_fallback, Smi) - - static inline InterceptorInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(InterceptorInfo) - DECLARE_VERIFIER(InterceptorInfo) - - static const int kGetterOffset = HeapObject::kHeaderSize; - static const int kSetterOffset = kGetterOffset + kPointerSize; - static const int kQueryOffset = kSetterOffset + kPointerSize; - static const int kDeleterOffset = kQueryOffset + kPointerSize; - static const int kEnumeratorOffset = kDeleterOffset + kPointerSize; - static const int kDataOffset = kEnumeratorOffset + kPointerSize; - static const int kFallbackOffset = kDataOffset + kPointerSize; - static const int kSize = kFallbackOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(InterceptorInfo); -}; - - -class CallHandlerInfo: public Struct { - public: - DECL_ACCESSORS(callback, Object) - DECL_ACCESSORS(data, Object) - - static inline CallHandlerInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(CallHandlerInfo) - DECLARE_VERIFIER(CallHandlerInfo) - - static const int kCallbackOffset = HeapObject::kHeaderSize; - static const int kDataOffset = kCallbackOffset + kPointerSize; - static const int kSize = kDataOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(CallHandlerInfo); -}; - - -class TemplateInfo: public Struct { - public: - DECL_ACCESSORS(tag, Object) - DECL_ACCESSORS(property_list, Object) - - DECLARE_VERIFIER(TemplateInfo) - - static const int kTagOffset = HeapObject::kHeaderSize; - static const int kPropertyListOffset = kTagOffset + kPointerSize; - static const int kHeaderSize = kPropertyListOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(TemplateInfo); -}; - - -class FunctionTemplateInfo: public TemplateInfo { - public: - DECL_ACCESSORS(serial_number, Object) - DECL_ACCESSORS(call_code, Object) - DECL_ACCESSORS(property_accessors, Object) - DECL_ACCESSORS(prototype_template, Object) - DECL_ACCESSORS(parent_template, Object) - DECL_ACCESSORS(named_property_handler, Object) - DECL_ACCESSORS(indexed_property_handler, Object) - DECL_ACCESSORS(instance_template, Object) - DECL_ACCESSORS(class_name, Object) - DECL_ACCESSORS(signature, Object) - DECL_ACCESSORS(instance_call_handler, Object) - DECL_ACCESSORS(access_check_info, Object) - DECL_ACCESSORS(flag, Smi) - - inline int length(); - inline void set_length(int value); - - // Following properties use flag bits. - DECL_BOOLEAN_ACCESSORS(hidden_prototype) - DECL_BOOLEAN_ACCESSORS(undetectable) - // If the bit is set, object instances created by this function - // requires access check. - DECL_BOOLEAN_ACCESSORS(needs_access_check) - DECL_BOOLEAN_ACCESSORS(read_only_prototype) - - static inline FunctionTemplateInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(FunctionTemplateInfo) - DECLARE_VERIFIER(FunctionTemplateInfo) - - static const int kSerialNumberOffset = TemplateInfo::kHeaderSize; - static const int kCallCodeOffset = kSerialNumberOffset + kPointerSize; - static const int kPropertyAccessorsOffset = kCallCodeOffset + kPointerSize; - static const int kPrototypeTemplateOffset = - kPropertyAccessorsOffset + kPointerSize; - static const int kParentTemplateOffset = - kPrototypeTemplateOffset + kPointerSize; - static const int kNamedPropertyHandlerOffset = - kParentTemplateOffset + kPointerSize; - static const int kIndexedPropertyHandlerOffset = - kNamedPropertyHandlerOffset + kPointerSize; - static const int kInstanceTemplateOffset = - kIndexedPropertyHandlerOffset + kPointerSize; - static const int kClassNameOffset = kInstanceTemplateOffset + kPointerSize; - static const int kSignatureOffset = kClassNameOffset + kPointerSize; - static const int kInstanceCallHandlerOffset = kSignatureOffset + kPointerSize; - static const int kAccessCheckInfoOffset = - kInstanceCallHandlerOffset + kPointerSize; - static const int kFlagOffset = kAccessCheckInfoOffset + kPointerSize; - static const int kLengthOffset = kFlagOffset + kPointerSize; - static const int kSize = kLengthOffset + kPointerSize; - - private: - // Bit position in the flag, from least significant bit position. - static const int kHiddenPrototypeBit = 0; - static const int kUndetectableBit = 1; - static const int kNeedsAccessCheckBit = 2; - static const int kReadOnlyPrototypeBit = 3; - - DISALLOW_IMPLICIT_CONSTRUCTORS(FunctionTemplateInfo); -}; - - -class ObjectTemplateInfo: public TemplateInfo { - public: - DECL_ACCESSORS(constructor, Object) - DECL_ACCESSORS(internal_field_count, Object) - DECL_ACCESSORS(has_external_resource, Object) - DECL_ACCESSORS(use_user_object_comparison, Object) - - static inline ObjectTemplateInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(ObjectTemplateInfo) - DECLARE_VERIFIER(ObjectTemplateInfo) - - static const int kConstructorOffset = TemplateInfo::kHeaderSize; - static const int kInternalFieldCountOffset = - kConstructorOffset + kPointerSize; - static const int kHasExternalResourceOffset = - kInternalFieldCountOffset + kPointerSize; - static const int kUseUserObjectComparisonOffset = - kHasExternalResourceOffset + kPointerSize; - static const int kSize = kUseUserObjectComparisonOffset + kPointerSize; -}; - - -class SignatureInfo: public Struct { - public: - DECL_ACCESSORS(receiver, Object) - DECL_ACCESSORS(args, Object) - - static inline SignatureInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(SignatureInfo) - DECLARE_VERIFIER(SignatureInfo) - - static const int kReceiverOffset = Struct::kHeaderSize; - static const int kArgsOffset = kReceiverOffset + kPointerSize; - static const int kSize = kArgsOffset + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(SignatureInfo); -}; - - -class TypeSwitchInfo: public Struct { - public: - DECL_ACCESSORS(types, Object) - - static inline TypeSwitchInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(TypeSwitchInfo) - DECLARE_VERIFIER(TypeSwitchInfo) - - static const int kTypesOffset = Struct::kHeaderSize; - static const int kSize = kTypesOffset + kPointerSize; -}; - - -#ifdef ENABLE_DEBUGGER_SUPPORT -// The DebugInfo class holds additional information for a function being -// debugged. -class DebugInfo: public Struct { - public: - // The shared function info for the source being debugged. - DECL_ACCESSORS(shared, SharedFunctionInfo) - // Code object for the original code. - DECL_ACCESSORS(original_code, Code) - // Code object for the patched code. This code object is the code object - // currently active for the function. - DECL_ACCESSORS(code, Code) - // Fixed array holding status information for each active break point. - DECL_ACCESSORS(break_points, FixedArray) - - // Check if there is a break point at a code position. - bool HasBreakPoint(int code_position); - // Get the break point info object for a code position. - Object* GetBreakPointInfo(int code_position); - // Clear a break point. - static void ClearBreakPoint(Handle<DebugInfo> debug_info, - int code_position, - Handle<Object> break_point_object); - // Set a break point. - static void SetBreakPoint(Handle<DebugInfo> debug_info, int code_position, - int source_position, int statement_position, - Handle<Object> break_point_object); - // Get the break point objects for a code position. - Object* GetBreakPointObjects(int code_position); - // Find the break point info holding this break point object. - static Object* FindBreakPointInfo(Handle<DebugInfo> debug_info, - Handle<Object> break_point_object); - // Get the number of break points for this function. - int GetBreakPointCount(); - - static inline DebugInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(DebugInfo) - DECLARE_VERIFIER(DebugInfo) - - static const int kSharedFunctionInfoIndex = Struct::kHeaderSize; - static const int kOriginalCodeIndex = kSharedFunctionInfoIndex + kPointerSize; - static const int kPatchedCodeIndex = kOriginalCodeIndex + kPointerSize; - static const int kActiveBreakPointsCountIndex = - kPatchedCodeIndex + kPointerSize; - static const int kBreakPointsStateIndex = - kActiveBreakPointsCountIndex + kPointerSize; - static const int kSize = kBreakPointsStateIndex + kPointerSize; - - private: - static const int kNoBreakPointInfo = -1; - - // Lookup the index in the break_points array for a code position. - int GetBreakPointInfoIndex(int code_position); - - DISALLOW_IMPLICIT_CONSTRUCTORS(DebugInfo); -}; - - -// The BreakPointInfo class holds information for break points set in a -// function. The DebugInfo object holds a BreakPointInfo object for each code -// position with one or more break points. -class BreakPointInfo: public Struct { - public: - // The position in the code for the break point. - DECL_ACCESSORS(code_position, Smi) - // The position in the source for the break position. - DECL_ACCESSORS(source_position, Smi) - // The position in the source for the last statement before this break - // position. - DECL_ACCESSORS(statement_position, Smi) - // List of related JavaScript break points. - DECL_ACCESSORS(break_point_objects, Object) - - // Removes a break point. - static void ClearBreakPoint(Handle<BreakPointInfo> info, - Handle<Object> break_point_object); - // Set a break point. - static void SetBreakPoint(Handle<BreakPointInfo> info, - Handle<Object> break_point_object); - // Check if break point info has this break point object. - static bool HasBreakPointObject(Handle<BreakPointInfo> info, - Handle<Object> break_point_object); - // Get the number of break points for this code position. - int GetBreakPointCount(); - - static inline BreakPointInfo* cast(Object* obj); - - // Dispatched behavior. - DECLARE_PRINTER(BreakPointInfo) - DECLARE_VERIFIER(BreakPointInfo) - - static const int kCodePositionIndex = Struct::kHeaderSize; - static const int kSourcePositionIndex = kCodePositionIndex + kPointerSize; - static const int kStatementPositionIndex = - kSourcePositionIndex + kPointerSize; - static const int kBreakPointObjectsIndex = - kStatementPositionIndex + kPointerSize; - static const int kSize = kBreakPointObjectsIndex + kPointerSize; - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(BreakPointInfo); -}; -#endif // ENABLE_DEBUGGER_SUPPORT - - -#undef DECL_BOOLEAN_ACCESSORS -#undef DECL_ACCESSORS -#undef DECLARE_VERIFIER - -#define VISITOR_SYNCHRONIZATION_TAGS_LIST(V) \ - V(kStringTable, "string_table", "(Internalized strings)") \ - V(kExternalStringsTable, "external_strings_table", "(External strings)") \ - V(kStrongRootList, "strong_root_list", "(Strong roots)") \ - V(kInternalizedString, "internalized_string", "(Internal string)") \ - V(kBootstrapper, "bootstrapper", "(Bootstrapper)") \ - V(kTop, "top", "(Isolate)") \ - V(kRelocatable, "relocatable", "(Relocatable)") \ - V(kDebug, "debug", "(Debugger)") \ - V(kCompilationCache, "compilationcache", "(Compilation cache)") \ - V(kHandleScope, "handlescope", "(Handle scope)") \ - V(kBuiltins, "builtins", "(Builtins)") \ - V(kGlobalHandles, "globalhandles", "(Global handles)") \ - V(kThreadManager, "threadmanager", "(Thread manager)") \ - V(kExtensions, "Extensions", "(Extensions)") - -class VisitorSynchronization : public AllStatic { - public: -#define DECLARE_ENUM(enum_item, ignore1, ignore2) enum_item, - enum SyncTag { - VISITOR_SYNCHRONIZATION_TAGS_LIST(DECLARE_ENUM) - kNumberOfSyncTags - }; -#undef DECLARE_ENUM - - static const char* const kTags[kNumberOfSyncTags]; - static const char* const kTagNames[kNumberOfSyncTags]; -}; - -// Abstract base class for visiting, and optionally modifying, the -// pointers contained in Objects. Used in GC and serialization/deserialization. -class ObjectVisitor BASE_EMBEDDED { - public: - virtual ~ObjectVisitor() {} - - // Visits a contiguous arrays of pointers in the half-open range - // [start, end). Any or all of the values may be modified on return. - virtual void VisitPointers(Object** start, Object** end) = 0; - - // To allow lazy clearing of inline caches the visitor has - // a rich interface for iterating over Code objects.. - - // Visits a code target in the instruction stream. - virtual void VisitCodeTarget(RelocInfo* rinfo); - - // Visits a code entry in a JS function. - virtual void VisitCodeEntry(Address entry_address); - - // Visits a global property cell reference in the instruction stream. - virtual void VisitGlobalPropertyCell(RelocInfo* rinfo); - - // Visits a runtime entry in the instruction stream. - virtual void VisitRuntimeEntry(RelocInfo* rinfo) {} - - // Visits the resource of an ASCII or two-byte string. - virtual void VisitExternalAsciiString( - v8::String::ExternalAsciiStringResource** resource) {} - virtual void VisitExternalTwoByteString( - v8::String::ExternalStringResource** resource) {} - - // Visits a debug call target in the instruction stream. - virtual void VisitDebugTarget(RelocInfo* rinfo); - - // Visits the byte sequence in a function's prologue that contains information - // about the code's age. - virtual void VisitCodeAgeSequence(RelocInfo* rinfo); - - // Handy shorthand for visiting a single pointer. - virtual void VisitPointer(Object** p) { VisitPointers(p, p + 1); } - - // Visit pointer embedded into a code object. - virtual void VisitEmbeddedPointer(RelocInfo* rinfo); - - // Visits a contiguous arrays of external references (references to the C++ - // heap) in the half-open range [start, end). Any or all of the values - // may be modified on return. - virtual void VisitExternalReferences(Address* start, Address* end) {} - - virtual void VisitExternalReference(RelocInfo* rinfo); - - inline void VisitExternalReference(Address* p) { - VisitExternalReferences(p, p + 1); - } - - // Visits a handle that has an embedder-assigned class ID. - virtual void VisitEmbedderReference(Object** p, uint16_t class_id) {} - - // Intended for serialization/deserialization checking: insert, or - // check for the presence of, a tag at this position in the stream. - // Also used for marking up GC roots in heap snapshots. - virtual void Synchronize(VisitorSynchronization::SyncTag tag) {} -}; - - -class StructBodyDescriptor : public - FlexibleBodyDescriptor<HeapObject::kHeaderSize> { - public: - static inline int SizeOf(Map* map, HeapObject* object) { - return map->instance_size(); - } -}; - - -// BooleanBit is a helper class for setting and getting a bit in an -// integer or Smi. -class BooleanBit : public AllStatic { - public: - static inline bool get(Smi* smi, int bit_position) { - return get(smi->value(), bit_position); - } - - static inline bool get(int value, int bit_position) { - return (value & (1 << bit_position)) != 0; - } - - static inline Smi* set(Smi* smi, int bit_position, bool v) { - return Smi::FromInt(set(smi->value(), bit_position, v)); - } - - static inline int set(int value, int bit_position, bool v) { - if (v) { - value |= (1 << bit_position); - } else { - value &= ~(1 << bit_position); - } - return value; - } -}; - -} } // namespace v8::internal - -#endif // V8_OBJECTS_H_ |