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-rw-r--r--deps/v8/src/objects/map.h115
1 files changed, 63 insertions, 52 deletions
diff --git a/deps/v8/src/objects/map.h b/deps/v8/src/objects/map.h
index 0880b73b66..7424ee4181 100644
--- a/deps/v8/src/objects/map.h
+++ b/deps/v8/src/objects/map.h
@@ -18,10 +18,16 @@ namespace internal {
enum InstanceType : uint16_t;
-#define VISITOR_ID_LIST(V) \
+#define DATA_ONLY_VISITOR_ID_LIST(V) \
+ V(BigInt) \
+ V(ByteArray) \
+ V(DataObject) \
+ V(FixedDoubleArray) \
+ V(SeqOneByteString) \
+ V(SeqTwoByteString)
+
+#define POINTER_VISITOR_ID_LIST(V) \
V(AllocationSite) \
- V(BigInt) \
- V(ByteArray) \
V(BytecodeArray) \
V(Cell) \
V(Code) \
@@ -29,14 +35,12 @@ enum InstanceType : uint16_t;
V(ConsString) \
V(Context) \
V(DataHandler) \
- V(DataObject) \
V(DescriptorArray) \
V(EmbedderDataArray) \
V(EphemeronHashTable) \
V(FeedbackCell) \
V(FeedbackVector) \
V(FixedArray) \
- V(FixedDoubleArray) \
V(FixedFloat64Array) \
V(FixedTypedArrayBase) \
V(FreeSpace) \
@@ -47,7 +51,6 @@ enum InstanceType : uint16_t;
V(JSObject) \
V(JSObjectFast) \
V(JSTypedArray) \
- V(JSWeakCell) \
V(JSWeakRef) \
V(JSWeakCollection) \
V(Map) \
@@ -57,8 +60,6 @@ enum InstanceType : uint16_t;
V(PropertyArray) \
V(PropertyCell) \
V(PrototypeInfo) \
- V(SeqOneByteString) \
- V(SeqTwoByteString) \
V(SharedFunctionInfo) \
V(ShortcutCandidate) \
V(SlicedString) \
@@ -72,24 +73,26 @@ enum InstanceType : uint16_t;
V(UncompiledDataWithoutPreparseData) \
V(UncompiledDataWithPreparseData) \
V(WasmInstanceObject) \
- V(WeakArray)
-
-// For data objects, JS objects and structs along with generic visitor which
-// can visit object of any size we provide visitors specialized by
-// object size in words.
-// Ids of specialized visitors are declared in a linear order (without
-// holes) starting from the id of visitor specialized for 2 words objects
-// (base visitor id) and ending with the id of generic visitor.
-// Method GetVisitorIdForSize depends on this ordering to calculate visitor
-// id of specialized visitor from given instance size, base visitor id and
-// generic visitor's id.
+ V(WeakArray) \
+ V(WeakCell)
+
+// Objects with the same visitor id are processed in the same way by
+// the heap visitors. The visitor ids for data only objects must precede
+// other visitor ids. We rely on kDataOnlyVisitorIdCount for quick check
+// of whether an object contains only data or may contain pointers.
enum VisitorId {
#define VISITOR_ID_ENUM_DECL(id) kVisit##id,
- VISITOR_ID_LIST(VISITOR_ID_ENUM_DECL)
+ DATA_ONLY_VISITOR_ID_LIST(VISITOR_ID_ENUM_DECL) kDataOnlyVisitorIdCount,
+ POINTER_VISITOR_ID_LIST(VISITOR_ID_ENUM_DECL)
#undef VISITOR_ID_ENUM_DECL
kVisitorIdCount
};
+enum class ObjectFields {
+ kDataOnly,
+ kMaybePointers,
+};
+
typedef std::vector<Handle<Map>> MapHandles;
// All heap objects have a Map that describes their structure.
@@ -272,6 +275,10 @@ class Map : public HeapObject {
//
DECL_PRIMITIVE_ACCESSORS(bit_field3, uint32_t)
+ // Clear uninitialized padding space. This ensures that the snapshot content
+ // is deterministic. Depending on the V8 build mode there could be no padding.
+ V8_INLINE void clear_padding();
+
// Bit positions for |bit_field3|.
#define MAP_BIT_FIELD3_FIELDS(V, _) \
V(EnumLengthBits, int, kDescriptorIndexBitCount, _) \
@@ -501,11 +508,10 @@ class Map : public HeapObject {
int modify_index, PropertyConstness new_constness,
Representation new_representation,
Handle<FieldType> new_field_type);
- // Returns true if |descriptor|'th property is a field that may be generalized
- // by just updating current map.
- static inline bool IsInplaceGeneralizableField(PropertyConstness constness,
- Representation representation,
- FieldType field_type);
+ // Returns true if the |field_type| is the most general one for
+ // given |representation|.
+ static inline bool IsMostGeneralFieldType(Representation representation,
+ FieldType field_type);
// Generalizes constness, representation and field_type if objects with given
// instance type can have fast elements that can be transitioned by stubs or
@@ -806,6 +812,12 @@ class Map : public HeapObject {
DECL_PRIMITIVE_ACCESSORS(visitor_id, VisitorId)
+ static ObjectFields ObjectFieldsFrom(VisitorId visitor_id) {
+ return (visitor_id < kDataOnlyVisitorIdCount)
+ ? ObjectFields::kDataOnly
+ : ObjectFields::kMaybePointers;
+ }
+
static Handle<Map> TransitionToPrototype(Isolate* isolate, Handle<Map> map,
Handle<Object> prototype);
@@ -815,29 +827,29 @@ class Map : public HeapObject {
static const int kMaxPreAllocatedPropertyFields = 255;
// Layout description.
-#define MAP_FIELDS(V) \
- /* Raw data fields. */ \
- V(kInstanceSizeInWordsOffset, kUInt8Size) \
- V(kInObjectPropertiesStartOrConstructorFunctionIndexOffset, kUInt8Size) \
- V(kUsedOrUnusedInstanceSizeInWordsOffset, kUInt8Size) \
- V(kVisitorIdOffset, kUInt8Size) \
- V(kInstanceTypeOffset, kUInt16Size) \
- V(kBitFieldOffset, kUInt8Size) \
- V(kBitField2Offset, kUInt8Size) \
- V(kBitField3Offset, kUInt32Size) \
- V(k64BitArchPaddingOffset, \
- kSystemPointerSize == kUInt32Size ? 0 : kUInt32Size) \
- /* Pointer fields. */ \
- V(kPointerFieldsBeginOffset, 0) \
- V(kPrototypeOffset, kTaggedSize) \
- V(kConstructorOrBackPointerOffset, kTaggedSize) \
- V(kTransitionsOrPrototypeInfoOffset, kTaggedSize) \
- V(kDescriptorsOffset, kTaggedSize) \
- V(kLayoutDescriptorOffset, FLAG_unbox_double_fields ? kTaggedSize : 0) \
- V(kDependentCodeOffset, kTaggedSize) \
- V(kPrototypeValidityCellOffset, kTaggedSize) \
- V(kPointerFieldsEndOffset, 0) \
- /* Total size. */ \
+#define MAP_FIELDS(V) \
+ /* Raw data fields. */ \
+ V(kInstanceSizeInWordsOffset, kUInt8Size) \
+ V(kInObjectPropertiesStartOrConstructorFunctionIndexOffset, kUInt8Size) \
+ V(kUsedOrUnusedInstanceSizeInWordsOffset, kUInt8Size) \
+ V(kVisitorIdOffset, kUInt8Size) \
+ V(kInstanceTypeOffset, kUInt16Size) \
+ V(kBitFieldOffset, kUInt8Size) \
+ V(kBitField2Offset, kUInt8Size) \
+ V(kBitField3Offset, kUInt32Size) \
+ /* Adds padding to make tagged fields kTaggedSize-aligned. */ \
+ V(kOptionalPaddingOffset, OBJECT_POINTER_PADDING(kOptionalPaddingOffset)) \
+ /* Pointer fields. */ \
+ V(kPointerFieldsBeginOffset, 0) \
+ V(kPrototypeOffset, kTaggedSize) \
+ V(kConstructorOrBackPointerOffset, kTaggedSize) \
+ V(kTransitionsOrPrototypeInfoOffset, kTaggedSize) \
+ V(kDescriptorsOffset, kTaggedSize) \
+ V(kLayoutDescriptorOffset, FLAG_unbox_double_fields ? kTaggedSize : 0) \
+ V(kDependentCodeOffset, kTaggedSize) \
+ V(kPrototypeValidityCellOffset, kTaggedSize) \
+ V(kPointerFieldsEndOffset, 0) \
+ /* Total size. */ \
V(kSize, 0)
DEFINE_FIELD_OFFSET_CONSTANTS(HeapObject::kHeaderSize, MAP_FIELDS)
@@ -997,12 +1009,11 @@ class NormalizedMapCache : public WeakFixedArray {
void Set(Handle<Map> fast_map, Handle<Map> normalized_map);
DECL_CAST(NormalizedMapCache)
-
- static inline bool IsNormalizedMapCache(const HeapObject obj);
-
DECL_VERIFIER(NormalizedMapCache)
private:
+ friend bool HeapObject::IsNormalizedMapCache() const;
+
static const int kEntries = 64;
static inline int GetIndex(Handle<Map> map);
@@ -1011,7 +1022,7 @@ class NormalizedMapCache : public WeakFixedArray {
Object get(int index);
void set(int index, Object value);
- OBJECT_CONSTRUCTORS(NormalizedMapCache, WeakFixedArray)
+ OBJECT_CONSTRUCTORS(NormalizedMapCache, WeakFixedArray);
};
} // namespace internal
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-01 10:44:39 +0000