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Diffstat (limited to 'deps/v8/src/objects/js-array.h')
-rw-r--r--deps/v8/src/objects/js-array.h231
1 files changed, 22 insertions, 209 deletions
diff --git a/deps/v8/src/objects/js-array.h b/deps/v8/src/objects/js-array.h
index 28cfe71f5d..b212848ce7 100644
--- a/deps/v8/src/objects/js-array.h
+++ b/deps/v8/src/objects/js-array.h
@@ -117,6 +117,28 @@ class JSArrayIterator : public JSObject {
DECL_ACCESSORS(iterated_object, Object)
// [next_index]: The [[ArrayIteratorNextIndex]] inobject property.
+ // The next_index is always a positive integer, and it points to
+ // the next index that is to be returned by this iterator. It's
+ // possible range is fixed depending on the [[iterated_object]]:
+ //
+ // 1. For JSArray's the next_index is always in Unsigned32
+ // range, and when the iterator reaches the end it's set
+ // to kMaxUInt32 to indicate that this iterator should
+ // never produce values anymore even if the "length"
+ // property of the JSArray changes at some later point.
+ // 2. For JSTypedArray's the next_index is always in
+ // UnsignedSmall range, and when the iterator terminates
+ // it's set to Smi::kMaxValue.
+ // 3. For all other JSReceiver's it's always between 0 and
+ // kMaxSafeInteger, and the latter value is used to mark
+ // termination.
+ //
+ // It's important that for 1. and 2. the value fits into the
+ // Unsigned32 range (UnsignedSmall is a subset of Unsigned32),
+ // since we use this knowledge in the fast-path for the array
+ // iterator next calls in TurboFan (in the JSCallReducer) to
+ // keep the index in Word32 representation. This invariant is
+ // checked in JSArrayIterator::JSArrayIteratorVerify().
DECL_ACCESSORS(next_index, Object)
// [kind]: the [[ArrayIterationKind]] inobject property.
@@ -132,215 +154,6 @@ class JSArrayIterator : public JSObject {
DISALLOW_IMPLICIT_CONSTRUCTORS(JSArrayIterator);
};
-// Whether a JSArrayBuffer is a SharedArrayBuffer or not.
-enum class SharedFlag { kNotShared, kShared };
-
-class JSArrayBuffer : public JSObject {
- public:
- // [byte_length]: length in bytes
- DECL_ACCESSORS(byte_length, Object)
-
- // [backing_store]: backing memory for this array
- DECL_ACCESSORS(backing_store, void)
-
- // For non-wasm, allocation_length and allocation_base are byte_length and
- // backing_store, respectively.
- inline size_t allocation_length() const;
- inline void* allocation_base() const;
-
- inline uint32_t bit_field() const;
- inline void set_bit_field(uint32_t bits);
-
- // [is_external]: true indicates that the embedder is in charge of freeing the
- // backing_store, while is_external == false means that v8 will free the
- // memory block once all ArrayBuffers referencing it are collected by the GC.
- inline bool is_external();
- inline void set_is_external(bool value);
-
- inline bool is_neuterable();
- inline void set_is_neuterable(bool value);
-
- inline bool was_neutered();
- inline void set_was_neutered(bool value);
-
- inline bool is_shared();
- inline void set_is_shared(bool value);
-
- inline bool is_growable();
- inline void set_is_growable(bool value);
-
- DECL_CAST(JSArrayBuffer)
-
- void Neuter();
-
- struct Allocation {
- Allocation(void* allocation_base, size_t length, void* backing_store,
- bool is_wasm_memory)
- : allocation_base(allocation_base),
- length(length),
- backing_store(backing_store),
- is_wasm_memory(is_wasm_memory) {}
-
- void* allocation_base;
- size_t length;
- void* backing_store;
- bool is_wasm_memory;
- };
-
- // Returns whether the buffer is tracked by the WasmMemoryTracker.
- inline bool is_wasm_memory() const;
-
- // Sets whether the buffer is tracked by the WasmMemoryTracker.
- void set_is_wasm_memory(bool is_wasm_memory);
-
- // Removes the backing store from the WasmMemoryTracker and sets
- // |is_wasm_memory| to false.
- void StopTrackingWasmMemory(Isolate* isolate);
-
- void FreeBackingStoreFromMainThread();
- static void FreeBackingStore(Isolate* isolate, Allocation allocation);
-
- V8_EXPORT_PRIVATE static void Setup(
- Handle<JSArrayBuffer> array_buffer, Isolate* isolate, bool is_external,
- void* data, size_t allocated_length,
- SharedFlag shared = SharedFlag::kNotShared, bool is_wasm_memory = false);
-
- // Returns false if array buffer contents could not be allocated.
- // In this case, |array_buffer| will not be set up.
- static bool SetupAllocatingData(
- Handle<JSArrayBuffer> array_buffer, Isolate* isolate,
- size_t allocated_length, bool initialize = true,
- SharedFlag shared = SharedFlag::kNotShared) V8_WARN_UNUSED_RESULT;
-
- // Dispatched behavior.
- DECL_PRINTER(JSArrayBuffer)
- DECL_VERIFIER(JSArrayBuffer)
-
- static const int kByteLengthOffset = JSObject::kHeaderSize;
- // The rest of the fields are not JSObjects, so they are not iterated over in
- // objects-body-descriptors-inl.h.
- static const int kBackingStoreOffset = kByteLengthOffset + kPointerSize;
- static const int kBitFieldSlot = kBackingStoreOffset + kPointerSize;
-#if V8_TARGET_LITTLE_ENDIAN || !V8_HOST_ARCH_64_BIT
- static const int kBitFieldOffset = kBitFieldSlot;
-#else
- static const int kBitFieldOffset = kBitFieldSlot + kInt32Size;
-#endif
- static const int kSize = kBitFieldSlot + kPointerSize;
-
- static const int kSizeWithEmbedderFields =
- kSize + v8::ArrayBuffer::kEmbedderFieldCount * kPointerSize;
-
- // Iterates all fields in the object including internal ones except
- // kBackingStoreOffset and kBitFieldSlot.
- class BodyDescriptor;
- // No weak fields.
- typedef BodyDescriptor BodyDescriptorWeak;
-
- class IsExternal : public BitField<bool, 1, 1> {};
- class IsNeuterable : public BitField<bool, 2, 1> {};
- class WasNeutered : public BitField<bool, 3, 1> {};
- class IsShared : public BitField<bool, 4, 1> {};
- class IsGrowable : public BitField<bool, 5, 1> {};
- class IsWasmMemory : public BitField<bool, 6, 1> {};
-
- private:
- DISALLOW_IMPLICIT_CONSTRUCTORS(JSArrayBuffer);
-};
-
-class JSArrayBufferView : public JSObject {
- public:
- // [buffer]: ArrayBuffer that this typed array views.
- DECL_ACCESSORS(buffer, Object)
-
- // [byte_offset]: offset of typed array in bytes.
- DECL_ACCESSORS(byte_offset, Object)
-
- // [byte_length]: length of typed array in bytes.
- DECL_ACCESSORS(byte_length, Object)
-
- DECL_CAST(JSArrayBufferView)
-
- DECL_VERIFIER(JSArrayBufferView)
-
- inline bool WasNeutered() const;
-
- static const int kBufferOffset = JSObject::kHeaderSize;
- static const int kByteOffsetOffset = kBufferOffset + kPointerSize;
- static const int kByteLengthOffset = kByteOffsetOffset + kPointerSize;
- static const int kViewSize = kByteLengthOffset + kPointerSize;
-
- private:
-#ifdef VERIFY_HEAP
- DECL_ACCESSORS(raw_byte_offset, Object)
- DECL_ACCESSORS(raw_byte_length, Object)
-#endif
-
- DISALLOW_IMPLICIT_CONSTRUCTORS(JSArrayBufferView);
-};
-
-class JSTypedArray : public JSArrayBufferView {
- public:
- // [length]: length of typed array in elements.
- DECL_ACCESSORS(length, Object)
- inline uint32_t length_value() const;
-
- // ES6 9.4.5.3
- V8_WARN_UNUSED_RESULT static Maybe<bool> DefineOwnProperty(
- Isolate* isolate, Handle<JSTypedArray> o, Handle<Object> key,
- PropertyDescriptor* desc, ShouldThrow should_throw);
-
- DECL_CAST(JSTypedArray)
-
- ExternalArrayType type();
- V8_EXPORT_PRIVATE size_t element_size();
-
- Handle<JSArrayBuffer> GetBuffer();
-
- // Whether the buffer's backing store is on-heap or off-heap.
- inline bool is_on_heap() const;
-
- static inline MaybeHandle<JSTypedArray> Validate(Isolate* isolate,
- Handle<Object> receiver,
- const char* method_name);
-
- // Dispatched behavior.
- DECL_PRINTER(JSTypedArray)
- DECL_VERIFIER(JSTypedArray)
-
- static const int kLengthOffset = kViewSize;
- static const int kSize = kLengthOffset + kPointerSize;
-
- static const int kSizeWithEmbedderFields =
- kSize + v8::ArrayBufferView::kEmbedderFieldCount * kPointerSize;
-
- private:
- static Handle<JSArrayBuffer> MaterializeArrayBuffer(
- Handle<JSTypedArray> typed_array);
-#ifdef VERIFY_HEAP
- DECL_ACCESSORS(raw_length, Object)
-#endif
-
- DISALLOW_IMPLICIT_CONSTRUCTORS(JSTypedArray);
-};
-
-class JSDataView : public JSArrayBufferView {
- public:
- DECL_CAST(JSDataView)
-
- // Dispatched behavior.
- DECL_PRINTER(JSDataView)
- DECL_VERIFIER(JSDataView)
-
- static const int kSize = kViewSize;
-
- static const int kSizeWithEmbedderFields =
- kSize + v8::ArrayBufferView::kEmbedderFieldCount * kPointerSize;
-
- private:
- DISALLOW_IMPLICIT_CONSTRUCTORS(JSDataView);
-};
-
} // namespace internal
} // namespace v8
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