v8/src/builtins/wasm.tq

// Copyright 2020 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-wasm-gen.h'

namespace runtime {
extern runtime WasmMemoryGrow(Context, WasmInstanceObject, Smi): Smi;
extern runtime WasmRefFunc(Context, WasmInstanceObject, Smi): JSAny;
extern runtime WasmTableInit(
    Context, WasmInstanceObject, Object, Object, Smi, Smi, Smi): JSAny;
extern runtime WasmTableCopy(
    Context, WasmInstanceObject, Object, Object, Smi, Smi, Smi): JSAny;
extern runtime WasmFunctionTableGet(
    Context, WasmInstanceObject, Smi, Smi): JSAny;
extern runtime WasmFunctionTableSet(
    Context, WasmInstanceObject, Smi, Smi, Object): JSAny;
extern runtime ThrowWasmError(Context, Smi): JSAny;
extern runtime Throw(Context, Object): JSAny;
extern runtime ReThrow(Context, Object): JSAny;
extern runtime WasmTriggerTierUp(Context, WasmInstanceObject): JSAny;
extern runtime WasmStackGuard(Context): JSAny;
extern runtime ThrowWasmStackOverflow(Context): JSAny;
extern runtime WasmTraceMemory(Context, Smi): JSAny;
extern runtime WasmTraceEnter(Context): JSAny;
extern runtime WasmTraceExit(Context, Smi): JSAny;
extern runtime WasmAtomicNotify(
    Context, WasmInstanceObject, Number, Number): Smi;
extern runtime WasmI32AtomicWait(
    Context, WasmInstanceObject, Number, Number, BigInt): Smi;
extern runtime WasmI64AtomicWait(
    Context, WasmInstanceObject, Number, BigInt, BigInt): Smi;
extern runtime WasmAllocateRtt(Context, Smi, Map): Map;
}

namespace unsafe {
extern macro TimesTaggedSize(intptr): intptr;
extern macro Allocate(intptr): HeapObject;
}

namespace wasm {
const kFuncTableType: constexpr int31 generates 'wasm::HeapType::kFunc';

extern macro WasmBuiltinsAssembler::LoadInstanceFromFrame(): WasmInstanceObject;

// WasmInstanceObject has a field layout that Torque can't handle yet.
// TODO(bbudge) Eliminate these functions when Torque is ready.
extern macro WasmBuiltinsAssembler::LoadContextFromInstance(WasmInstanceObject):
    NativeContext;
extern macro WasmBuiltinsAssembler::LoadTablesFromInstance(WasmInstanceObject):
    FixedArray;
extern macro WasmBuiltinsAssembler::LoadExternalFunctionsFromInstance(
    WasmInstanceObject): FixedArray;
extern macro WasmBuiltinsAssembler::LoadManagedObjectMapsFromInstance(
    WasmInstanceObject): FixedArray;

macro LoadContextFromFrame(): NativeContext {
  return LoadContextFromInstance(LoadInstanceFromFrame());
}

builtin WasmInt32ToHeapNumber(val: int32): HeapNumber {
  return AllocateHeapNumberWithValue(Convert<float64>(val));
}

builtin WasmTaggedNonSmiToInt32(implicit context: Context)(val: JSAnyNotSmi):
    int32 {
  return ChangeTaggedNonSmiToInt32(val);
}

builtin WasmTaggedToFloat64(implicit context: Context)(val: JSAny): float64 {
  return ChangeTaggedToFloat64(val);
}

builtin WasmMemoryGrow(numPages: int32): int32 {
  if (!IsValidPositiveSmi(ChangeInt32ToIntPtr(numPages)))
    return Int32Constant(-1);
  const instance: WasmInstanceObject = LoadInstanceFromFrame();
  const context: NativeContext = LoadContextFromInstance(instance);
  const result: Smi =
      runtime::WasmMemoryGrow(context, instance, SmiFromInt32(numPages));
  return SmiToInt32(result);
}

builtin WasmTableInit(
    dstRaw: uint32, srcRaw: uint32, sizeRaw: uint32, tableIndex: Smi,
    segmentIndex: Smi): JSAny {
  try {
    const instance: WasmInstanceObject = LoadInstanceFromFrame();
    const dst: Smi = Convert<PositiveSmi>(dstRaw) otherwise TableOutOfBounds;
    const src: Smi = Convert<PositiveSmi>(srcRaw) otherwise TableOutOfBounds;
    const size: Smi = Convert<PositiveSmi>(sizeRaw) otherwise TableOutOfBounds;
    tail runtime::WasmTableInit(
        LoadContextFromInstance(instance), instance, tableIndex, segmentIndex,
        dst, src, size);
  } label TableOutOfBounds deferred {
    tail ThrowWasmTrapTableOutOfBounds();
  }
}

builtin WasmTableCopy(
    dstRaw: uint32, srcRaw: uint32, sizeRaw: uint32, dstTable: Smi,
    srcTable: Smi): JSAny {
  try {
    const instance: WasmInstanceObject = LoadInstanceFromFrame();
    const dst: Smi = Convert<PositiveSmi>(dstRaw) otherwise TableOutOfBounds;
    const src: Smi = Convert<PositiveSmi>(srcRaw) otherwise TableOutOfBounds;
    const size: Smi = Convert<PositiveSmi>(sizeRaw) otherwise TableOutOfBounds;
    tail runtime::WasmTableCopy(
        LoadContextFromInstance(instance), instance, dstTable, srcTable, dst,
        src, size);
  } label TableOutOfBounds deferred {
    tail ThrowWasmTrapTableOutOfBounds();
  }
}

builtin WasmTableGet(tableIndex: intptr, index: int32): Object {
  const instance: WasmInstanceObject = LoadInstanceFromFrame();
  const entryIndex: intptr = ChangeInt32ToIntPtr(index);
  try {
    assert(IsValidPositiveSmi(tableIndex));
    if (!IsValidPositiveSmi(entryIndex)) goto IndexOutOfRange;

    const tables: FixedArray = LoadTablesFromInstance(instance);
    const table: WasmTableObject = %RawDownCast<WasmTableObject>(
        LoadFixedArrayElement(tables, tableIndex));
    const entriesCount: intptr = Convert<intptr, Smi>(table.current_length);
    if (entryIndex >= entriesCount) goto IndexOutOfRange;

    const entries: FixedArray = table.entries;
    const entry: Object = LoadFixedArrayElement(entries, entryIndex);

    try {
      const entryObject: HeapObject =
          TaggedToHeapObject<HeapObject>(entry) otherwise ReturnEntry;
      if (IsTuple2Map(entryObject.map)) goto CallRuntime;
      goto ReturnEntry;
    } label ReturnEntry {
      return entry;
    }
  } label CallRuntime deferred {
    tail runtime::WasmFunctionTableGet(
        LoadContextFromInstance(instance), instance, SmiFromIntPtr(tableIndex),
        SmiFromIntPtr(entryIndex));
  } label IndexOutOfRange deferred {
    tail ThrowWasmTrapTableOutOfBounds();
  }
}

builtin WasmTableSet(tableIndex: intptr, index: int32, value: Object): Object {
  const instance: WasmInstanceObject = LoadInstanceFromFrame();
  const entryIndex: intptr = ChangeInt32ToIntPtr(index);
  try {
    assert(IsValidPositiveSmi(tableIndex));
    if (!IsValidPositiveSmi(entryIndex)) goto IndexOutOfRange;

    const tables: FixedArray = LoadTablesFromInstance(instance);
    const table: WasmTableObject = %RawDownCast<WasmTableObject>(
        LoadFixedArrayElement(tables, tableIndex));

    // Fall back to the runtime to set funcrefs, since we have to update
    // function dispatch tables.
    const tableType: Smi = table.raw_type;
    if (tableType == SmiConstant(kFuncTableType)) goto CallRuntime;

    const entriesCount: intptr = Convert<intptr, Smi>(table.current_length);
    if (entryIndex >= entriesCount) goto IndexOutOfRange;

    const entries: FixedArray = table.entries;
    StoreFixedArrayElement(entries, entryIndex, value);
    return Undefined;
  } label CallRuntime deferred {
    tail runtime::WasmFunctionTableSet(
        LoadContextFromInstance(instance), instance, SmiFromIntPtr(tableIndex),
        SmiFromIntPtr(entryIndex), value);
  } label IndexOutOfRange deferred {
    tail ThrowWasmTrapTableOutOfBounds();
  }
}

builtin WasmRefFunc(index: uint32): Object {
  const instance: WasmInstanceObject = LoadInstanceFromFrame();
  try {
    const table: FixedArray = LoadExternalFunctionsFromInstance(instance);
    if (table == Undefined) goto CallRuntime;
    const functionIndex: intptr = Signed(ChangeUint32ToWord(index));
    const result: Object = LoadFixedArrayElement(table, functionIndex);
    if (result == Undefined) goto CallRuntime;
    return result;
  } label CallRuntime deferred {
    tail runtime::WasmRefFunc(
        LoadContextFromInstance(instance), instance, SmiFromUint32(index));
  }
}

builtin WasmThrow(exception: Object): JSAny {
  tail runtime::Throw(LoadContextFromFrame(), exception);
}

builtin WasmRethrow(exception: Object): JSAny {
  if (exception == Null) tail ThrowWasmTrapRethrowNull();
  tail runtime::ReThrow(LoadContextFromFrame(), exception);
}

builtin WasmTriggerTierUp(): JSAny {
  const instance: WasmInstanceObject = LoadInstanceFromFrame();
  tail runtime::WasmTriggerTierUp(LoadContextFromFrame(), instance);
}

builtin WasmStackGuard(): JSAny {
  tail runtime::WasmStackGuard(LoadContextFromFrame());
}

builtin WasmStackOverflow(): JSAny {
  tail runtime::ThrowWasmStackOverflow(LoadContextFromFrame());
}

builtin WasmTraceMemory(info: Smi): JSAny {
  tail runtime::WasmTraceMemory(LoadContextFromFrame(), info);
}

builtin WasmTraceEnter(): JSAny {
  tail runtime::WasmTraceEnter(LoadContextFromFrame());
}

builtin WasmTraceExit(info: Smi): JSAny {
  tail runtime::WasmTraceExit(LoadContextFromFrame(), info);
}

builtin WasmAllocateJSArray(implicit context: Context)(size: Smi): JSArray {
  const map: Map = GetFastPackedElementsJSArrayMap();
  return AllocateJSArray(ElementsKind::PACKED_ELEMENTS, map, size, size);
}

builtin WasmAllocateRtt(implicit context: Context)(
    typeIndex: Smi, parent: Map): Map {
  tail runtime::WasmAllocateRtt(context, typeIndex, parent);
}

builtin WasmAllocateStructWithRtt(implicit context: Context)(rtt: Map):
    HeapObject {
  const instanceSize: intptr =
      unsafe::TimesTaggedSize(Convert<intptr>(rtt.instance_size_in_words));
  const result: HeapObject = unsafe::Allocate(instanceSize);
  *UnsafeConstCast(&result.map) = rtt;
  return result;
}

builtin WasmIsRttSubtype(implicit context: Context)(sub: Map, super: Map): Smi {
  let map = sub;
  while (true) {
    if (map == super) return SmiConstant(1);  // "true"
    // This code relies on the fact that we use a non-WasmObject map as the
    // end of the chain, e.g. for "rtt any", which then doesn't have a
    // WasmTypeInfo.
    // TODO(7748): Use a more explicit sentinel mechanism?
    const maybeTypeInfo = map.constructor_or_back_pointer_or_native_context;
    if (!Is<WasmTypeInfo>(maybeTypeInfo)) return SmiConstant(0);  // "false"
    const typeInfo = %RawDownCast<WasmTypeInfo>(maybeTypeInfo);
    map = typeInfo.parent;
  }
  unreachable;
}

// Redeclaration with different typing (value is an Object, not JSAny).
extern transitioning runtime
CreateDataProperty(implicit context: Context)(JSReceiver, JSAny, Object);

transitioning builtin WasmAllocateObjectWrapper(implicit context: Context)(
    obj: Object): JSObject {
  // Note: {obj} can be null, or i31ref. The code below is agnostic to that.
  const wrapper = NewJSObject();
  const symbol = WasmWrappedObjectSymbolConstant();
  CreateDataProperty(wrapper, symbol, obj);
  return wrapper;
}

builtin WasmInt32ToNumber(value: int32): Number {
  return ChangeInt32ToTagged(value);
}

builtin WasmUint32ToNumber(value: uint32): Number {
  return ChangeUint32ToTagged(value);
}

builtin UintPtr53ToNumber(value: uintptr): Number {
  if (value <= kSmiMaxValue) return Convert<Smi>(Convert<intptr>(value));
  const valueFloat = ChangeUintPtrToFloat64(value);
  // Values need to be within [0..2^53], such that they can be represented as
  // float64.
  assert(ChangeFloat64ToUintPtr(valueFloat) == value);
  return AllocateHeapNumberWithValue(valueFloat);
}

extern builtin I64ToBigInt(intptr): BigInt;

builtin WasmAtomicNotify(offset: uintptr, count: uint32): uint32 {
  const instance: WasmInstanceObject = LoadInstanceFromFrame();
  const result: Smi = runtime::WasmAtomicNotify(
      LoadContextFromInstance(instance), instance, UintPtr53ToNumber(offset),
      WasmUint32ToNumber(count));
  return Unsigned(SmiToInt32(result));
}

builtin WasmI32AtomicWait64(
    offset: uintptr, expectedValue: int32, timeout: intptr): uint32 {
  if constexpr (Is64()) {
    const instance: WasmInstanceObject = LoadInstanceFromFrame();
    const result: Smi = runtime::WasmI32AtomicWait(
        LoadContextFromInstance(instance), instance, UintPtr53ToNumber(offset),
        WasmInt32ToNumber(expectedValue), I64ToBigInt(timeout));
    return Unsigned(SmiToInt32(result));
  } else {
    unreachable;
  }
}

builtin WasmI64AtomicWait64(
    offset: uintptr, expectedValue: intptr, timeout: intptr): uint32 {
  if constexpr (Is64()) {
    const instance: WasmInstanceObject = LoadInstanceFromFrame();
    const result: Smi = runtime::WasmI64AtomicWait(
        LoadContextFromInstance(instance), instance, UintPtr53ToNumber(offset),
        I64ToBigInt(expectedValue), I64ToBigInt(timeout));
    return Unsigned(SmiToInt32(result));
  } else {
    unreachable;
  }
}

extern macro TryHasOwnProperty(HeapObject, Map, InstanceType, Name): never
    labels Found, NotFound, Bailout;
type OnNonExistent constexpr 'OnNonExistent';
const kReturnUndefined: constexpr OnNonExistent
    generates 'OnNonExistent::kReturnUndefined';
extern macro SmiConstant(constexpr OnNonExistent): Smi;
extern transitioning builtin GetPropertyWithReceiver(implicit context: Context)(
    JSAny, Name, JSAny, Smi): JSAny;

transitioning builtin WasmGetOwnProperty(implicit context: Context)(
    object: Object, uniqueName: Name): JSAny {
  try {
    const heapObject: HeapObject =
        TaggedToHeapObject(object) otherwise NotFound;
    const receiver: JSReceiver =
        Cast<JSReceiver>(heapObject) otherwise NotFound;
    try {
      TryHasOwnProperty(
          receiver, receiver.map, receiver.instanceType, uniqueName)
          otherwise Found, NotFound, Bailout;
    } label Found {
      tail GetPropertyWithReceiver(
          receiver, uniqueName, receiver, SmiConstant(kReturnUndefined));
    }
  } label NotFound deferred {
    return Undefined;
  } label Bailout deferred {
    unreachable;
  }
}

// Trap builtins.

builtin WasmTrap(error: Smi): JSAny {
  tail runtime::ThrowWasmError(LoadContextFromFrame(), error);
}

builtin ThrowWasmTrapUnreachable(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapUnreachable));
}

builtin ThrowWasmTrapMemOutOfBounds(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapMemOutOfBounds));
}

builtin ThrowWasmTrapUnalignedAccess(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapUnalignedAccess));
}

builtin ThrowWasmTrapDivByZero(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapDivByZero));
}

builtin ThrowWasmTrapDivUnrepresentable(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapDivUnrepresentable));
}

builtin ThrowWasmTrapRemByZero(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapRemByZero));
}

builtin ThrowWasmTrapFloatUnrepresentable(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapFloatUnrepresentable));
}

builtin ThrowWasmTrapFuncSigMismatch(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapFuncSigMismatch));
}

builtin ThrowWasmTrapDataSegmentDropped(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapDataSegmentDropped));
}

builtin ThrowWasmTrapElemSegmentDropped(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapElemSegmentDropped));
}

builtin ThrowWasmTrapTableOutOfBounds(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapTableOutOfBounds));
}

builtin ThrowWasmTrapBrOnExnNull(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapBrOnExnNull));
}

builtin ThrowWasmTrapRethrowNull(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapRethrowNull));
}

builtin ThrowWasmTrapNullDereference(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapNullDereference));
}

builtin ThrowWasmTrapIllegalCast(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapIllegalCast));
}

builtin ThrowWasmTrapArrayOutOfBounds(): JSAny {
  tail WasmTrap(SmiConstant(MessageTemplate::kWasmTrapArrayOutOfBounds));
}
}