builtins-typed-array-gen.cc

// Copyright 2017 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "src/builtins/builtins-typed-array-gen.h"

#include "src/builtins/builtins-constructor-gen.h"
#include "src/builtins/builtins-utils-gen.h"
#include "src/builtins/builtins.h"
#include "src/builtins/growable-fixed-array-gen.h"
#include "src/execution/protectors.h"
#include "src/handles/handles-inl.h"
#include "src/heap/factory-inl.h"
#include "src/objects/elements-kind.h"
#include "src/objects/js-array-buffer-inl.h"

namespace v8 {
namespace internal {

// -----------------------------------------------------------------------------
// ES6 section 22.2 TypedArray Objects

// Sets the embedder fields to 0 for a TypedArray which is under construction.
void TypedArrayBuiltinsAssembler::SetupTypedArrayEmbedderFields(
    TNode<JSTypedArray> holder) {
  for (int offset = JSTypedArray::kHeaderSize;
       offset < JSTypedArray::kSizeWithEmbedderFields; offset += kTaggedSize) {
    // TODO(v8:10391, saelo): Handle external pointers in EmbedderDataSlot
    StoreObjectField(holder, offset, SmiConstant(0));
  }
}

// Allocate a new ArrayBuffer and initialize it with empty properties and
// elements.
// TODO(bmeurer,v8:4153): Rename this and maybe fix up the implementation a bit.
TNode<JSArrayBuffer> TypedArrayBuiltinsAssembler::AllocateEmptyOnHeapBuffer(
    TNode<Context> context) {
  TNode<NativeContext> native_context = LoadNativeContext(context);
  TNode<Map> map =
      CAST(LoadContextElement(native_context, Context::ARRAY_BUFFER_MAP_INDEX));
  TNode<FixedArray> empty_fixed_array = EmptyFixedArrayConstant();

  TNode<JSArrayBuffer> buffer = UncheckedCast<JSArrayBuffer>(
      Allocate(JSArrayBuffer::kSizeWithEmbedderFields));
  StoreMapNoWriteBarrier(buffer, map);
  StoreObjectFieldNoWriteBarrier(buffer, JSArray::kPropertiesOrHashOffset,
                                 empty_fixed_array);
  StoreObjectFieldNoWriteBarrier(buffer, JSArray::kElementsOffset,
                                 empty_fixed_array);
  // Setup the ArrayBuffer.
  //  - Set BitField to 0.
  //  - Set IsExternal and IsDetachable bits of BitFieldSlot.
  //  - Set the byte_length field to zero.
  //  - Set backing_store to null/Smi(0).
  //  - Set extension to null.
  //  - Set all embedder fields to Smi(0).
  if (FIELD_SIZE(JSArrayBuffer::kOptionalPaddingOffset) != 0) {
    DCHECK_EQ(4, FIELD_SIZE(JSArrayBuffer::kOptionalPaddingOffset));
    StoreObjectFieldNoWriteBarrier(
        buffer, JSArrayBuffer::kOptionalPaddingOffset, Int32Constant(0));
  }
  int32_t bitfield_value = (1 << JSArrayBuffer::IsExternalBit::kShift) |
                           (1 << JSArrayBuffer::IsDetachableBit::kShift);
  StoreObjectFieldNoWriteBarrier(buffer, JSArrayBuffer::kBitFieldOffset,
                                 Int32Constant(bitfield_value));

  StoreObjectFieldNoWriteBarrier(buffer, JSArrayBuffer::kDetachKeyOffset,
                                 UndefinedConstant());
  StoreBoundedSizeToObject(buffer, JSArrayBuffer::kRawByteLengthOffset,
                           UintPtrConstant(0));
  StoreSandboxedPointerToObject(buffer, JSArrayBuffer::kBackingStoreOffset,
                                EmptyBackingStoreBufferConstant());
#ifdef V8_COMPRESS_POINTERS
  // When pointer compression is enabled, the extension slot contains a
  // (lazily-initialized) external pointer handle.
  StoreObjectFieldNoWriteBarrier(buffer, JSArrayBuffer::kExtensionOffset,
                                 ExternalPointerHandleNullConstant());
#else
  StoreObjectFieldNoWriteBarrier(buffer, JSArrayBuffer::kExtensionOffset,
                                 IntPtrConstant(0));
#endif
  for (int offset = JSArrayBuffer::kHeaderSize;
       offset < JSArrayBuffer::kSizeWithEmbedderFields; offset += kTaggedSize) {
    // TODO(v8:10391, saelo): Handle external pointers in EmbedderDataSlot
    StoreObjectFieldNoWriteBarrier(buffer, offset, SmiConstant(0));
  }
  return buffer;
}

TF_BUILTIN(TypedArrayBaseConstructor, TypedArrayBuiltinsAssembler) {
  auto context = Parameter<Context>(Descriptor::kContext);
  ThrowTypeError(context, MessageTemplate::kConstructAbstractClass,
                 "TypedArray");
}

// ES #sec-typedarray-constructors
TF_BUILTIN(TypedArrayConstructor, TypedArrayBuiltinsAssembler) {
  auto context = Parameter<Context>(Descriptor::kContext);
  auto target = Parameter<JSFunction>(Descriptor::kJSTarget);
  auto new_target = Parameter<Object>(Descriptor::kJSNewTarget);
  TNode<IntPtrT> argc = ChangeInt32ToIntPtr(
      UncheckedParameter<Int32T>(Descriptor::kJSActualArgumentsCount));
  CodeStubArguments args(this, argc);
  TNode<Object> arg1 = args.GetOptionalArgumentValue(0);
  TNode<Object> arg2 = args.GetOptionalArgumentValue(1);
  TNode<Object> arg3 = args.GetOptionalArgumentValue(2);

  // If NewTarget is undefined, throw a TypeError exception.
  // All the TypedArray constructors have this as the first step:
  // https://tc39.github.io/ecma262/#sec-typedarray-constructors
  Label throwtypeerror(this, Label::kDeferred);
  GotoIf(IsUndefined(new_target), &throwtypeerror);

  TNode<Object> result = CallBuiltin(Builtin::kCreateTypedArray, context,
                                     target, new_target, arg1, arg2, arg3);
  args.PopAndReturn(result);

  BIND(&throwtypeerror);
  {
    TNode<String> name =
        CAST(CallRuntime(Runtime::kGetFunctionName, context, target));
    ThrowTypeError(context, MessageTemplate::kConstructorNotFunction, name);
  }
}

// ES6 #sec-get-%typedarray%.prototype.bytelength
TF_BUILTIN(TypedArrayPrototypeByteLength, TypedArrayBuiltinsAssembler) {
  const char* const kMethodName = "get TypedArray.prototype.byteLength";
  auto context = Parameter<Context>(Descriptor::kContext);
  auto receiver = Parameter<Object>(Descriptor::kReceiver);

  // Check if the {receiver} is actually a JSTypedArray.
  ThrowIfNotInstanceType(context, receiver, JS_TYPED_ARRAY_TYPE, kMethodName);

  TNode<JSTypedArray> receiver_array = CAST(receiver);
  TNode<JSArrayBuffer> receiver_buffer =
      LoadJSArrayBufferViewBuffer(receiver_array);

  Label variable_length(this), normal(this);
  Branch(IsVariableLengthJSArrayBufferView(receiver_array), &variable_length,
         &normal);
  BIND(&variable_length);
  {
    Return(ChangeUintPtrToTagged(LoadVariableLengthJSTypedArrayByteLength(
        context, receiver_array, receiver_buffer)));
  }

  BIND(&normal);
  {
    // Default to zero if the {receiver}s buffer was detached.
    TNode<UintPtrT> byte_length = Select<UintPtrT>(
        IsDetachedBuffer(receiver_buffer), [=] { return UintPtrConstant(0); },
        [=] { return LoadJSArrayBufferViewByteLength(receiver_array); });
    Return(ChangeUintPtrToTagged(byte_length));
  }
}

// ES6 #sec-get-%typedarray%.prototype.byteoffset
TF_BUILTIN(TypedArrayPrototypeByteOffset, TypedArrayBuiltinsAssembler) {
  const char* const kMethodName = "get TypedArray.prototype.byteOffset";
  auto context = Parameter<Context>(Descriptor::kContext);
  auto receiver = Parameter<Object>(Descriptor::kReceiver);

  // Check if the {receiver} is actually a JSTypedArray.
  ThrowIfNotInstanceType(context, receiver, JS_TYPED_ARRAY_TYPE, kMethodName);

  // Default to zero if the {receiver}s buffer was detached / out of bounds.
  Label detached_or_oob(this), not_detached_nor_oob(this);
  IsJSArrayBufferViewDetachedOrOutOfBounds(CAST(receiver), &detached_or_oob,
                                           &not_detached_nor_oob);
  BIND(&detached_or_oob);
  Return(ChangeUintPtrToTagged(UintPtrConstant(0)));

  BIND(&not_detached_nor_oob);
  Return(
      ChangeUintPtrToTagged(LoadJSArrayBufferViewByteOffset(CAST(receiver))));
}

// ES6 #sec-get-%typedarray%.prototype.length
TF_BUILTIN(TypedArrayPrototypeLength, TypedArrayBuiltinsAssembler) {
  const char* const kMethodName = "get TypedArray.prototype.length";
  auto context = Parameter<Context>(Descriptor::kContext);
  auto receiver = Parameter<Object>(Descriptor::kReceiver);

  // Check if the {receiver} is actually a JSTypedArray.
  ThrowIfNotInstanceType(context, receiver, JS_TYPED_ARRAY_TYPE, kMethodName);

  TNode<JSTypedArray> receiver_array = CAST(receiver);
  TVARIABLE(UintPtrT, length);
  Label detached(this), end(this);
  length = LoadJSTypedArrayLengthAndCheckDetached(receiver_array, &detached);
  Return(ChangeUintPtrToTagged(length.value()));
  BIND(&detached);
  Return(ChangeUintPtrToTagged(UintPtrConstant(0)));
}

TNode<BoolT> TypedArrayBuiltinsAssembler::IsUint8ElementsKind(
    TNode<Int32T> kind) {
  return Word32Or(
      Word32Or(Word32Equal(kind, Int32Constant(UINT8_ELEMENTS)),
               Word32Equal(kind, Int32Constant(UINT8_CLAMPED_ELEMENTS))),
      Word32Or(
          Word32Equal(kind, Int32Constant(RAB_GSAB_UINT8_ELEMENTS)),
          Word32Equal(kind, Int32Constant(RAB_GSAB_UINT8_CLAMPED_ELEMENTS))));
}

TNode<BoolT> TypedArrayBuiltinsAssembler::IsBigInt64ElementsKind(
    TNode<Int32T> kind) {
  static_assert(BIGUINT64_ELEMENTS + 1 == BIGINT64_ELEMENTS);
  return Word32Or(
      IsElementsKindInRange(kind, BIGUINT64_ELEMENTS, BIGINT64_ELEMENTS),
      IsElementsKindInRange(kind, RAB_GSAB_BIGUINT64_ELEMENTS,
                            RAB_GSAB_BIGINT64_ELEMENTS));
}

TNode<IntPtrT> TypedArrayBuiltinsAssembler::GetTypedArrayElementSize(
    TNode<Int32T> elements_kind) {
  TVARIABLE(IntPtrT, element_size);

  DispatchTypedArrayByElementsKind(
      elements_kind,
      [&](ElementsKind el_kind, int size, int typed_array_fun_index) {
        element_size = IntPtrConstant(size);
      });

  return element_size.value();
}

TorqueStructTypedArrayElementsInfo
TypedArrayBuiltinsAssembler::GetTypedArrayElementsInfo(
    TNode<JSTypedArray> typed_array) {
  return GetTypedArrayElementsInfo(LoadMap(typed_array));
}

TorqueStructTypedArrayElementsInfo
TypedArrayBuiltinsAssembler::GetTypedArrayElementsInfo(TNode<Map> map) {
  TNode<Int32T> elements_kind = LoadMapElementsKind(map);
  TVARIABLE(UintPtrT, var_size_log2);
  TVARIABLE(Map, var_map);
  ReadOnlyRoots roots(isolate());

  DispatchTypedArrayByElementsKind(
      elements_kind,
      [&](ElementsKind kind, int size, int typed_array_fun_index) {
        DCHECK_GT(size, 0);
        var_size_log2 = UintPtrConstant(ElementsKindToShiftSize(kind));
      });

  return TorqueStructTypedArrayElementsInfo{var_size_log2.value(),
                                            elements_kind};
}

TNode<JSFunction> TypedArrayBuiltinsAssembler::GetDefaultConstructor(
    TNode<Context> context, TNode<JSTypedArray> exemplar) {
  TVARIABLE(IntPtrT, context_slot);
  TNode<Int32T> elements_kind = LoadElementsKind(exemplar);

  DispatchTypedArrayByElementsKind(
      elements_kind,
      [&](ElementsKind el_kind, int size, int typed_array_function_index) {
        context_slot = IntPtrConstant(typed_array_function_index);
      });

  return CAST(
      LoadContextElement(LoadNativeContext(context), context_slot.value()));
}

TNode<JSTypedArray> TypedArrayBuiltinsAssembler::ValidateTypedArray(
    TNode<Context> context, TNode<Object> obj, const char* method_name) {
  // If it is not a typed array, throw
  ThrowIfNotInstanceType(context, obj, JS_TYPED_ARRAY_TYPE, method_name);

  // If the typed array's buffer is detached, throw
  ThrowIfArrayBufferViewBufferIsDetached(context, CAST(obj), method_name);

  // TODO(v8:11111): Throw if the RAB / GSAB is OOB.
  return CAST(obj);
}

TNode<UintPtrT> TypedArrayBuiltinsAssembler::ValidateTypedArrayAndGetLength(
    TNode<Context> context, TNode<Object> obj, const char* method_name) {
  // If it is not a typed array, throw
  ThrowIfNotInstanceType(context, obj, JS_TYPED_ARRAY_TYPE, method_name);

  Label detached_or_oob(this), not_detached_nor_oob(this);
  TNode<UintPtrT> length =
      LoadJSTypedArrayLengthAndCheckDetached(CAST(obj), &detached_or_oob);
  Goto(&not_detached_nor_oob);

  BIND(&detached_or_oob);
  ThrowTypeError(context, MessageTemplate::kDetachedOperation, method_name);

  BIND(&not_detached_nor_oob);
  return length;
}

void TypedArrayBuiltinsAssembler::CallCMemmove(TNode<RawPtrT> dest_ptr,
                                               TNode<RawPtrT> src_ptr,
                                               TNode<UintPtrT> byte_length) {
  TNode<ExternalReference> memmove =
      ExternalConstant(ExternalReference::libc_memmove_function());
  CallCFunction(memmove, MachineType::AnyTagged(),
                std::make_pair(MachineType::Pointer(), dest_ptr),
                std::make_pair(MachineType::Pointer(), src_ptr),
                std::make_pair(MachineType::UintPtr(), byte_length));
}

void TypedArrayBuiltinsAssembler::CallCRelaxedMemmove(
    TNode<RawPtrT> dest_ptr, TNode<RawPtrT> src_ptr,
    TNode<UintPtrT> byte_length) {
  TNode<ExternalReference> memmove =
      ExternalConstant(ExternalReference::relaxed_memmove_function());
  CallCFunction(memmove, MachineType::AnyTagged(),
                std::make_pair(MachineType::Pointer(), dest_ptr),
                std::make_pair(MachineType::Pointer(), src_ptr),
                std::make_pair(MachineType::UintPtr(), byte_length));
}

void TypedArrayBuiltinsAssembler::CallCMemcpy(TNode<RawPtrT> dest_ptr,
                                              TNode<RawPtrT> src_ptr,
                                              TNode<UintPtrT> byte_length) {
  TNode<ExternalReference> memcpy =
      ExternalConstant(ExternalReference::libc_memcpy_function());
  CallCFunction(memcpy, MachineType::AnyTagged(),
                std::make_pair(MachineType::Pointer(), dest_ptr),
                std::make_pair(MachineType::Pointer(), src_ptr),
                std::make_pair(MachineType::UintPtr(), byte_length));
}

void TypedArrayBuiltinsAssembler::CallCRelaxedMemcpy(
    TNode<RawPtrT> dest_ptr, TNode<RawPtrT> src_ptr,
    TNode<UintPtrT> byte_length) {
  TNode<ExternalReference> relaxed_memcpy =
      ExternalConstant(ExternalReference::relaxed_memcpy_function());
  CallCFunction(relaxed_memcpy, MachineType::AnyTagged(),
                std::make_pair(MachineType::Pointer(), dest_ptr),
                std::make_pair(MachineType::Pointer(), src_ptr),
                std::make_pair(MachineType::UintPtr(), byte_length));
}

void TypedArrayBuiltinsAssembler::CallCMemset(TNode<RawPtrT> dest_ptr,
                                              TNode<IntPtrT> value,
                                              TNode<UintPtrT> length) {
  TNode<ExternalReference> memset =
      ExternalConstant(ExternalReference::libc_memset_function());
  CallCFunction(memset, MachineType::AnyTagged(),
                std::make_pair(MachineType::Pointer(), dest_ptr),
                std::make_pair(MachineType::IntPtr(), value),
                std::make_pair(MachineType::UintPtr(), length));
}

void TypedArrayBuiltinsAssembler::
    CallCCopyFastNumberJSArrayElementsToTypedArray(
        TNode<Context> context, TNode<JSArray> source, TNode<JSTypedArray> dest,
        TNode<UintPtrT> source_length, TNode<UintPtrT> offset) {
  CSA_DCHECK(this,
             Word32BinaryNot(IsBigInt64ElementsKind(LoadElementsKind(dest))));
  TNode<ExternalReference> f = ExternalConstant(
      ExternalReference::copy_fast_number_jsarray_elements_to_typed_array());
  CallCFunction(f, MachineType::AnyTagged(),
                std::make_pair(MachineType::AnyTagged(), context),
                std::make_pair(MachineType::AnyTagged(), source),
                std::make_pair(MachineType::AnyTagged(), dest),
                std::make_pair(MachineType::UintPtr(), source_length),
                std::make_pair(MachineType::UintPtr(), offset));
}

void TypedArrayBuiltinsAssembler::CallCCopyTypedArrayElementsToTypedArray(
    TNode<JSTypedArray> source, TNode<JSTypedArray> dest,
    TNode<UintPtrT> source_length, TNode<UintPtrT> offset) {
  TNode<ExternalReference> f = ExternalConstant(
      ExternalReference::copy_typed_array_elements_to_typed_array());
  CallCFunction(f, MachineType::AnyTagged(),
                std::make_pair(MachineType::AnyTagged(), source),
                std::make_pair(MachineType::AnyTagged(), dest),
                std::make_pair(MachineType::UintPtr(), source_length),
                std::make_pair(MachineType::UintPtr(), offset));
}

void TypedArrayBuiltinsAssembler::CallCCopyTypedArrayElementsSlice(
    TNode<JSTypedArray> source, TNode<JSTypedArray> dest, TNode<UintPtrT> start,
    TNode<UintPtrT> end) {
  TNode<ExternalReference> f =
      ExternalConstant(ExternalReference::copy_typed_array_elements_slice());
  CallCFunction(f, MachineType::AnyTagged(),
                std::make_pair(MachineType::AnyTagged(), source),
                std::make_pair(MachineType::AnyTagged(), dest),
                std::make_pair(MachineType::UintPtr(), start),
                std::make_pair(MachineType::UintPtr(), end));
}

void TypedArrayBuiltinsAssembler::DispatchTypedArrayByElementsKind(
    TNode<Word32T> elements_kind, const TypedArraySwitchCase& case_function) {
  Label next(this), if_unknown_type(this, Label::kDeferred);

  int32_t elements_kinds[] = {
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype) TYPE##_ELEMENTS,
      TYPED_ARRAYS(TYPED_ARRAY_CASE) RAB_GSAB_TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
  };

#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype) Label if_##type##array(this);
  TYPED_ARRAYS(TYPED_ARRAY_CASE)
  RAB_GSAB_TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE

  Label* elements_kind_labels[] = {
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype) &if_##type##array,
      TYPED_ARRAYS(TYPED_ARRAY_CASE) RAB_GSAB_TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
  };
  static_assert(arraysize(elements_kinds) == arraysize(elements_kind_labels));

  Switch(elements_kind, &if_unknown_type, elements_kinds, elements_kind_labels,
         arraysize(elements_kinds));

#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype)   \
  BIND(&if_##type##array);                          \
  {                                                 \
    case_function(TYPE##_ELEMENTS, sizeof(ctype),   \
                  Context::TYPE##_ARRAY_FUN_INDEX); \
    Goto(&next);                                    \
  }
  TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE

#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, NON_RAB_GSAB_TYPE) \
  BIND(&if_##type##array);                                           \
  {                                                                  \
    case_function(TYPE##_ELEMENTS, sizeof(ctype),                    \
                  Context::NON_RAB_GSAB_TYPE##_ARRAY_FUN_INDEX);     \
    Goto(&next);                                                     \
  }
  RAB_GSAB_TYPED_ARRAYS_WITH_NON_RAB_GSAB_ELEMENTS_KIND(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE

  BIND(&if_unknown_type);
  Unreachable();

  BIND(&next);
}

void TypedArrayBuiltinsAssembler::SetJSTypedArrayOnHeapDataPtr(
    TNode<JSTypedArray> holder, TNode<ByteArray> base, TNode<UintPtrT> offset) {
  offset = UintPtrAdd(UintPtrConstant(ByteArray::kHeaderSize - kHeapObjectTag),
                      offset);
  if (COMPRESS_POINTERS_BOOL) {
    TNode<IntPtrT> full_base = Signed(BitcastTaggedToWord(base));
    TNode<Int32T> compressed_base = TruncateIntPtrToInt32(full_base);
    // TODO(v8:9706): Add a way to directly use kRootRegister value.
    TNode<IntPtrT> ptr_compr_cage_base =
        IntPtrSub(full_base, Signed(ChangeUint32ToWord(compressed_base)));
    // Add JSTypedArray::ExternalPointerCompensationForOnHeapArray() to offset.
    // See JSTypedArray::AddExternalPointerCompensationForDeserialization().
    DCHECK_EQ(
        isolate()->cage_base(),
        JSTypedArray::ExternalPointerCompensationForOnHeapArray(isolate()));
    offset = Unsigned(IntPtrAdd(offset, ptr_compr_cage_base));
  }

  StoreJSTypedArrayBasePointer(holder, base);
  StoreJSTypedArrayExternalPointerPtr(holder, ReinterpretCast<RawPtrT>(offset));
}

void TypedArrayBuiltinsAssembler::SetJSTypedArrayOffHeapDataPtr(
    TNode<JSTypedArray> holder, TNode<RawPtrT> base, TNode<UintPtrT> offset) {
  StoreObjectFieldNoWriteBarrier(holder, JSTypedArray::kBasePointerOffset,
                                 SmiConstant(0));

  base = RawPtrAdd(base, Signed(offset));
  StoreJSTypedArrayExternalPointerPtr(holder, base);
}

void TypedArrayBuiltinsAssembler::StoreJSTypedArrayElementFromNumeric(
    TNode<Context> context, TNode<JSTypedArray> typed_array,
    TNode<UintPtrT> index, TNode<Numeric> value, ElementsKind elements_kind) {
  TNode<RawPtrT> data_ptr = LoadJSTypedArrayDataPtr(typed_array);
  switch (elements_kind) {
    case UINT8_ELEMENTS:
    case UINT8_CLAMPED_ELEMENTS:
    case INT8_ELEMENTS:
    case UINT16_ELEMENTS:
    case INT16_ELEMENTS:
      StoreElement(data_ptr, elements_kind, index, SmiToInt32(CAST(value)));
      break;
    case UINT32_ELEMENTS:
    case INT32_ELEMENTS:
      StoreElement(data_ptr, elements_kind, index,
                   TruncateTaggedToWord32(context, value));
      break;
    case FLOAT32_ELEMENTS:
      StoreElement(data_ptr, elements_kind, index,
                   TruncateFloat64ToFloat32(LoadHeapNumberValue(CAST(value))));
      break;
    case FLOAT64_ELEMENTS:
      StoreElement(data_ptr, elements_kind, index,
                   LoadHeapNumberValue(CAST(value)));
      break;
    case BIGUINT64_ELEMENTS:
    case BIGINT64_ELEMENTS:
      StoreElement(data_ptr, elements_kind, index,
                   UncheckedCast<BigInt>(value));
      break;
    default:
      UNREACHABLE();
  }
}

template <typename TValue>
void TypedArrayBuiltinsAssembler::StoreJSTypedArrayElementFromPreparedValue(
    TNode<Context> context, TNode<JSTypedArray> typed_array,
    TNode<UintPtrT> index, TNode<TValue> prepared_value,
    ElementsKind elements_kind, Label* if_detached) {
  static_assert(
      std::is_same<TValue, Word32T>::value ||
          std::is_same<TValue, Float32T>::value ||
          std::is_same<TValue, Float64T>::value ||
          std::is_same<TValue, BigInt>::value,
      "Only Word32T, Float32T, Float64T or BigInt values are allowed");
  // ToNumber/ToBigInt may execute JavaScript code, which could detach
  // the array's buffer.
  TNode<JSArrayBuffer> buffer = LoadJSArrayBufferViewBuffer(typed_array);
  GotoIf(IsDetachedBuffer(buffer), if_detached);

  TNode<RawPtrT> data_ptr = LoadJSTypedArrayDataPtr(typed_array);
  StoreElement(data_ptr, elements_kind, index, prepared_value);
}

void TypedArrayBuiltinsAssembler::StoreJSTypedArrayElementFromTagged(
    TNode<Context> context, TNode<JSTypedArray> typed_array,
    TNode<UintPtrT> index, TNode<Object> value, ElementsKind elements_kind,
    Label* if_detached) {
  switch (elements_kind) {
    case UINT8_ELEMENTS:
    case INT8_ELEMENTS:
    case UINT16_ELEMENTS:
    case INT16_ELEMENTS:
    case UINT32_ELEMENTS:
    case INT32_ELEMENTS:
    case UINT8_CLAMPED_ELEMENTS: {
      auto prepared_value = PrepareValueForWriteToTypedArray<Word32T>(
          value, elements_kind, context);
      StoreJSTypedArrayElementFromPreparedValue(context, typed_array, index,
                                                prepared_value, elements_kind,
                                                if_detached);
      break;
    }
    case FLOAT32_ELEMENTS: {
      auto prepared_value = PrepareValueForWriteToTypedArray<Float32T>(
          value, elements_kind, context);
      StoreJSTypedArrayElementFromPreparedValue(context, typed_array, index,
                                                prepared_value, elements_kind,
                                                if_detached);
      break;
    }
    case FLOAT64_ELEMENTS: {
      auto prepared_value = PrepareValueForWriteToTypedArray<Float64T>(
          value, elements_kind, context);
      StoreJSTypedArrayElementFromPreparedValue(context, typed_array, index,
                                                prepared_value, elements_kind,
                                                if_detached);
      break;
    }
    case BIGINT64_ELEMENTS:
    case BIGUINT64_ELEMENTS: {
      auto prepared_value = PrepareValueForWriteToTypedArray<BigInt>(
          value, elements_kind, context);
      StoreJSTypedArrayElementFromPreparedValue(context, typed_array, index,
                                                prepared_value, elements_kind,
                                                if_detached);
      break;
    }
    default:
      UNREACHABLE();
  }
}

// ES #sec-get-%typedarray%.prototype-@@tostringtag
TF_BUILTIN(TypedArrayPrototypeToStringTag, TypedArrayBuiltinsAssembler) {
  auto receiver = Parameter<Object>(Descriptor::kReceiver);
  Label if_receiverisheapobject(this), return_undefined(this);
  Branch(TaggedIsSmi(receiver), &return_undefined, &if_receiverisheapobject);

  // Dispatch on the elements kind, offset by
  // FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND.
  static_assert(LAST_FIXED_TYPED_ARRAY_ELEMENTS_KIND + 1 ==
                FIRST_RAB_GSAB_FIXED_TYPED_ARRAY_ELEMENTS_KIND);
  size_t const kTypedElementsKindCount =
      LAST_RAB_GSAB_FIXED_TYPED_ARRAY_ELEMENTS_KIND -
      FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND + 1;
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype) \
  Label return_##type##array(this);               \
  BIND(&return_##type##array);                    \
  Return(StringConstant(#Type "Array"));
  TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE

  // clang-format off
  Label* elements_kind_labels[kTypedElementsKindCount] = {
  // The TYPED_ARRAYS macro is invoked twice because while the RAB/GSAB-backed
  // TAs have distinct ElementsKinds internally, they have the same "class"
  // name for toString output.
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype) &return_##type##array,
  TYPED_ARRAYS(TYPED_ARRAY_CASE)
  TYPED_ARRAYS(TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
  };

  int32_t elements_kinds[kTypedElementsKindCount] = {
#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype) \
  TYPE##_ELEMENTS - FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND,
  // The use of FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND below is not a typo! This
  // computes an index into elements_kind_labels, and all TypedArray
  // ElementsKind values are contiguous.
#define RAB_GSAB_TYPED_ARRAY_CASE(Type, type, TYPE, ctype) \
  TYPE##_ELEMENTS - FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND,
  TYPED_ARRAYS(TYPED_ARRAY_CASE)
  RAB_GSAB_TYPED_ARRAYS(RAB_GSAB_TYPED_ARRAY_CASE)
#undef TYPED_ARRAY_CASE
#undef RAB_GSAB_TYPED_ARRAY_CASE
  };
  // clang-format on

  // We offset the dispatch by FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND, so that
  // this can be turned into a non-sparse table switch for ideal performance.
  BIND(&if_receiverisheapobject);
  TNode<HeapObject> receiver_heap_object = CAST(receiver);
  TNode<Int32T> elements_kind =
      Int32Sub(LoadElementsKind(receiver_heap_object),
               Int32Constant(FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND));
  Switch(elements_kind, &return_undefined, elements_kinds, elements_kind_labels,
         kTypedElementsKindCount);

  BIND(&return_undefined);
  Return(UndefinedConstant());
}
}  // namespace internal
}  // namespace v8