| // Copyright (c) 2022, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| import 'dart:typed_data'; |
| |
| import 'package:kernel/ast.dart'; |
| import 'package:kernel/core_types.dart'; |
| import 'package:kernel/type_algebra.dart' |
| show FunctionTypeInstantiator, substitute; |
| import 'package:wasm_builder/wasm_builder.dart' as w; |
| |
| import 'class_info.dart'; |
| import 'closures.dart'; |
| import 'code_generator.dart'; |
| import 'param_info.dart'; |
| import 'translator.dart'; |
| import 'types.dart'; |
| |
| const int maxArrayNewFixedLength = 10000; |
| |
| class ConstantInfo { |
| final Constant constant; |
| final w.Global global; |
| final w.BaseFunction? function; |
| |
| ConstantInfo(this.constant, this.global, this.function); |
| |
| bool get isLazy => function != null; |
| |
| void _readGlobal(Translator translator, w.InstructionsBuilder b) { |
| translator.globals.readGlobal(b, global); |
| } |
| |
| w.ValueType readConstant(Translator translator, w.InstructionsBuilder b) { |
| final initFunction = function; |
| if (initFunction != null) { |
| // Lazily initialized constant. |
| w.ValueType type = global.type.type.withNullability(false); |
| w.Label done = b.block(const [], [type]); |
| _readGlobal(translator, b); |
| b.br_on_non_null(done); |
| |
| translator.callFunction(initFunction, b); |
| b.end(); |
| return type; |
| } else { |
| _readGlobal(translator, b); |
| return global.type.type; |
| } |
| } |
| } |
| |
| typedef ConstantCodeGenerator = void Function(w.InstructionsBuilder); |
| |
| /// Handles the creation of Dart constants. |
| /// |
| /// Each (non-trivial) constant is assigned to a Wasm global. Multiple |
| /// occurrences of the same constant use the same global. |
| /// |
| /// When possible, the constant is contained within the global initializer, |
| /// meaning the constant is initialized eagerly during module initialization. |
| /// If this would exceed built-in Wasm limits (in particular the maximum length |
| /// for `array.new_fixed`), the constant is lazy, meaning that the global starts |
| /// out uninitialized, and every use of the constant checks the global to see if |
| /// it has been initialized and calls an initialization function otherwise. |
| /// A constant is also forced to be lazy if any sub-constants (e.g. elements of |
| /// a constant list) are lazy. |
| class Constants { |
| final Translator translator; |
| final Map<Constant, ConstantInfo> constantInfo = {}; |
| w.DataSegmentBuilder? oneByteStringSegment; |
| w.DataSegmentBuilder? twoByteStringSegment; |
| late final ClassInfo typeInfo = translator.classInfo[translator.typeClass]!; |
| |
| final Map<DartType, InstanceConstant> _loweredTypeConstants = {}; |
| late final BoolConstant _cachedTrueConstant = BoolConstant(true); |
| late final BoolConstant _cachedFalseConstant = BoolConstant(false); |
| late final InstanceConstant _cachedDynamicType = |
| _makeTopTypeConstant(const DynamicType()); |
| late final InstanceConstant _cachedVoidType = |
| _makeTopTypeConstant(const VoidType()); |
| late final InstanceConstant _cachedNeverType = |
| _makeBottomTypeConstant(const NeverType.nonNullable()); |
| late final InstanceConstant _cachedNullType = |
| _makeBottomTypeConstant(const NullType()); |
| late final InstanceConstant _cachedNullableObjectType = |
| _makeTopTypeConstant(coreTypes.objectRawType(Nullability.nullable)); |
| late final InstanceConstant _cachedNonNullableObjectType = |
| _makeTopTypeConstant(coreTypes.objectRawType(Nullability.nonNullable)); |
| late final InstanceConstant _cachedNullableFunctionType = |
| _makeAbstractFunctionTypeConstant( |
| coreTypes.functionRawType(Nullability.nullable)); |
| late final InstanceConstant _cachedNonNullableFunctionType = |
| _makeAbstractFunctionTypeConstant( |
| coreTypes.functionRawType(Nullability.nonNullable)); |
| late final InstanceConstant _cachedNullableRecordType = |
| _makeAbstractRecordTypeConstant( |
| coreTypes.recordRawType(Nullability.nullable)); |
| late final InstanceConstant _cachedNonNullableRecordType = |
| _makeAbstractRecordTypeConstant( |
| coreTypes.recordRawType(Nullability.nonNullable)); |
| |
| bool currentlyCreating = false; |
| |
| Constants(this.translator); |
| |
| // All constant constructs should go in the main module. |
| Types get types => translator.types; |
| CoreTypes get coreTypes => translator.coreTypes; |
| |
| /// Makes a `WasmArray<_Type>` [InstanceConstant]. |
| InstanceConstant makeTypeArray(Iterable<DartType> types) { |
| return makeArrayOf( |
| translator.typeType, types.map(_lowerTypeConstant).toList()); |
| } |
| |
| /// Makes a `_NamedParameter` [InstanceConstant]. |
| InstanceConstant makeNamedParameterConstant(NamedType n) => |
| InstanceConstant(translator.namedParameterClass.reference, const [], { |
| translator.namedParameterNameField.fieldReference: |
| StringConstant(n.name), |
| translator.namedParameterTypeField.fieldReference: |
| _lowerTypeConstant(n.type), |
| translator.namedParameterIsRequiredField.fieldReference: |
| BoolConstant(n.isRequired), |
| }); |
| |
| /// Creates a `WasmArray<_NamedParameter>` to be used as field of |
| /// `_FunctionType`. |
| InstanceConstant makeNamedParametersArray(FunctionType type) => makeArrayOf( |
| translator.namedParameterType, |
| [for (final n in type.namedParameters) makeNamedParameterConstant(n)]); |
| |
| /// Creates a `WasmArray<T>` with the given [Constant]s |
| InstanceConstant makeArrayOf( |
| InterfaceType elementType, List<Constant> entries, |
| {bool mutable = true}) => |
| InstanceConstant( |
| mutable |
| ? translator.wasmArrayClass.reference |
| : translator.immutableWasmArrayClass.reference, |
| [ |
| elementType, |
| ], |
| { |
| mutable |
| ? translator.wasmArrayValueField.fieldReference |
| : translator.immutableWasmArrayValueField.fieldReference: |
| ListConstant(elementType, entries), |
| }); |
| |
| /// Ensure that the constant has a Wasm global assigned. |
| /// |
| /// Sub-constants must have Wasm globals assigned before the global for the |
| /// composite constant is assigned, since global initializers can only refer |
| /// to earlier globals. |
| ConstantInfo? ensureConstant(Constant constant) { |
| return ConstantCreator(this).ensureConstant(constant); |
| } |
| |
| /// Emit code to push a constant onto the stack. |
| void instantiateConstant( |
| w.InstructionsBuilder b, Constant constant, w.ValueType expectedType) { |
| if (expectedType == translator.voidMarker) return; |
| ConstantInstantiator(this, b, expectedType).instantiate(constant); |
| } |
| |
| InstanceConstant _lowerTypeConstant(DartType type) { |
| return _loweredTypeConstants[type] ??= _lowerTypeConstantImpl(type); |
| } |
| |
| InstanceConstant _lowerTypeConstantImpl(DartType type) { |
| return switch (type) { |
| DynamicType() => _cachedDynamicType, |
| VoidType() => _cachedVoidType, |
| NeverType() => _cachedNeverType, |
| NullType() => _cachedNullType, |
| InterfaceType(classNode: var c) when c == coreTypes.objectClass => |
| type.nullability == Nullability.nullable |
| ? _cachedNullableObjectType |
| : _cachedNonNullableObjectType, |
| InterfaceType(classNode: var c) when c == coreTypes.functionClass => |
| type.nullability == Nullability.nullable |
| ? _cachedNullableFunctionType |
| : _cachedNonNullableFunctionType, |
| InterfaceType(classNode: var c) when c == coreTypes.recordClass => |
| type.nullability == Nullability.nullable |
| ? _cachedNullableRecordType |
| : _cachedNonNullableRecordType, |
| InterfaceType() => _makeInterfaceTypeConstant(type), |
| FutureOrType() => _makeFutureOrTypeConstant(type), |
| FunctionType() => _makeFunctionTypeConstant(type), |
| TypeParameterType() => _makeTypeParameterTypeConstant(type), |
| StructuralParameterType() => _makeStructuralParameterTypeConstant(type), |
| ExtensionType() => _lowerTypeConstant(type.extensionTypeErasure), |
| RecordType() => _makeRecordTypeConstant(type), |
| IntersectionType() => throw 'Unexpected DartType: $type', |
| TypedefType() => throw 'Unexpected DartType: $type', |
| AuxiliaryType() => throw 'Unexpected DartType: $type', |
| InvalidType() => throw 'Unexpected DartType: $type', |
| }; |
| } |
| |
| InstanceConstant _makeTypeParameterTypeConstant(TypeParameterType type) { |
| final int environmentIndex = |
| types.interfaceTypeEnvironment.lookup(type.parameter); |
| return _makeTypeConstant( |
| translator.interfaceTypeParameterTypeClass, type.nullability, { |
| translator.interfaceTypeParameterTypeEnvironmentIndexField.fieldReference: |
| IntConstant(environmentIndex), |
| }); |
| } |
| |
| InstanceConstant _makeStructuralParameterTypeConstant( |
| StructuralParameterType type) { |
| final int index = types.getFunctionTypeParameterIndex(type.parameter); |
| return _makeTypeConstant( |
| translator.functionTypeParameterTypeClass, type.nullability, { |
| translator.functionTypeParameterTypeIndexField.fieldReference: |
| IntConstant(index), |
| }); |
| } |
| |
| InstanceConstant _makeInterfaceTypeConstant(InterfaceType type) { |
| return _makeTypeConstant(translator.interfaceTypeClass, type.nullability, { |
| translator.interfaceTypeClassIdField.fieldReference: |
| IntConstant(translator.classIdNumbering.classIds[type.classNode]!), |
| translator.interfaceTypeTypeArguments.fieldReference: |
| makeTypeArray(type.typeArguments), |
| }); |
| } |
| |
| InstanceConstant _makeFutureOrTypeConstant(FutureOrType type) { |
| return _makeTypeConstant(translator.futureOrTypeClass, type.nullability, { |
| translator.futureOrTypeTypeArgumentField.fieldReference: |
| _lowerTypeConstant(type.typeArgument), |
| }); |
| } |
| |
| InstanceConstant _makeRecordTypeConstant(RecordType type) { |
| final fieldTypes = makeTypeArray([ |
| ...type.positional, |
| ...type.named.map((named) => named.type), |
| ]); |
| final names = makeArrayOf(coreTypes.stringNonNullableRawType, |
| type.named.map((t) => StringConstant(t.name)).toList(), |
| mutable: false); |
| return _makeTypeConstant(translator.recordTypeClass, type.nullability, { |
| translator.recordTypeFieldTypesField.fieldReference: fieldTypes, |
| translator.recordTypeNamesField.fieldReference: names, |
| }); |
| } |
| |
| InstanceConstant _makeFunctionTypeConstant(FunctionType type) { |
| final typeParameterOffset = |
| IntConstant(types.computeFunctionTypeParameterOffset(type)); |
| final typeParameterBoundsConstant = |
| makeTypeArray(type.typeParameters.map((p) => p.bound)); |
| final typeParameterDefaultsConstant = |
| makeTypeArray(type.typeParameters.map((p) => p.defaultType)); |
| final returnTypeConstant = _lowerTypeConstant(type.returnType); |
| final positionalParametersConstant = |
| makeTypeArray(type.positionalParameters); |
| final requiredParameterCountConstant = |
| IntConstant(type.requiredParameterCount); |
| final namedParametersConstant = makeNamedParametersArray(type); |
| return _makeTypeConstant(translator.functionTypeClass, type.nullability, { |
| translator.functionTypeTypeParameterOffsetField.fieldReference: |
| typeParameterOffset, |
| translator.functionTypeTypeParameterBoundsField.fieldReference: |
| typeParameterBoundsConstant, |
| translator.functionTypeTypeParameterDefaultsField.fieldReference: |
| typeParameterDefaultsConstant, |
| translator.functionTypeReturnTypeField.fieldReference: returnTypeConstant, |
| translator.functionTypePositionalParametersField.fieldReference: |
| positionalParametersConstant, |
| translator.functionTypeRequiredParameterCountField.fieldReference: |
| requiredParameterCountConstant, |
| translator.functionTypeTypeParameterNamedParamsField.fieldReference: |
| namedParametersConstant, |
| }); |
| } |
| |
| InstanceConstant _makeTopTypeConstant(DartType type) { |
| assert(type is VoidType || |
| type is DynamicType || |
| type is InterfaceType && type.classNode == coreTypes.objectClass); |
| return _makeTypeConstant(translator.topTypeClass, type.nullability, { |
| translator.topTypeKindField.fieldReference: |
| IntConstant(types.topTypeKind(type)), |
| }); |
| } |
| |
| InstanceConstant _makeAbstractFunctionTypeConstant(InterfaceType type) { |
| assert(coreTypes.functionClass == type.classNode); |
| return _makeTypeConstant( |
| translator.abstractFunctionTypeClass, type.nullability, {}); |
| } |
| |
| InstanceConstant _makeAbstractRecordTypeConstant(InterfaceType type) { |
| assert(coreTypes.recordClass == type.classNode); |
| return _makeTypeConstant( |
| translator.abstractRecordTypeClass, type.nullability, {}); |
| } |
| |
| InstanceConstant _makeBottomTypeConstant(DartType type) { |
| assert(type is NeverType || |
| type is NullType || |
| type is InterfaceType && types.isSpecializedClass(type.classNode)); |
| return _makeTypeConstant(translator.bottomTypeClass, type.nullability, {}); |
| } |
| |
| InstanceConstant _makeTypeConstant(Class classNode, Nullability nullability, |
| Map<Reference, Constant> fieldValues) { |
| fieldValues[translator.typeIsDeclaredNullableField.fieldReference] = |
| nullability == Nullability.nullable |
| ? _cachedTrueConstant |
| : _cachedFalseConstant; |
| return InstanceConstant(classNode.reference, const [], fieldValues); |
| } |
| } |
| |
| class ConstantInstantiator extends ConstantVisitor<w.ValueType> |
| with ConstantVisitorDefaultMixin<w.ValueType> { |
| final Constants constants; |
| final w.InstructionsBuilder b; |
| final w.ValueType expectedType; |
| |
| ConstantInstantiator(this.constants, this.b, this.expectedType); |
| |
| Translator get translator => constants.translator; |
| |
| void instantiate(Constant constant) { |
| w.ValueType resultType = constant.accept(this); |
| if (translator.needsConversion(resultType, expectedType)) { |
| if (expectedType == const w.RefType.extern(nullable: true)) { |
| assert(resultType.isSubtypeOf(w.RefType.any(nullable: true))); |
| b.extern_externalize(); |
| } else { |
| // This only happens in invalid but unreachable code produced by the |
| // TFA dead-code elimination. |
| b.comment("Constant in incompatible context (constant: $constant, " |
| "expectedType: $expectedType, resultType: $resultType)"); |
| b.unreachable(); |
| } |
| } |
| } |
| |
| @override |
| w.ValueType defaultConstant(Constant constant) { |
| ConstantInfo info = ConstantCreator(constants).ensureConstant(constant)!; |
| return info.readConstant(translator, b); |
| } |
| |
| @override |
| w.ValueType visitUnevaluatedConstant(UnevaluatedConstant constant) { |
| if (constant == ParameterInfo.defaultValueSentinel) { |
| // Instantiate a sentinel value specific to the parameter type. |
| w.ValueType sentinelType = expectedType.withNullability(false); |
| assert(sentinelType is w.RefType, |
| "Default value sentinel for unboxed parameter"); |
| translator |
| .getDummyValuesCollectorForModule(b.module) |
| .instantiateDummyValue(b, sentinelType); |
| return sentinelType; |
| } |
| return super.visitUnevaluatedConstant(constant); |
| } |
| |
| @override |
| w.ValueType visitNullConstant(NullConstant node) { |
| b.ref_null(w.HeapType.none); |
| return const w.RefType.none(nullable: true); |
| } |
| |
| @override |
| w.ValueType visitBoolConstant(BoolConstant constant) { |
| if (expectedType is w.RefType) return defaultConstant(constant); |
| b.i32_const(constant.value ? 1 : 0); |
| return w.NumType.i32; |
| } |
| |
| @override |
| w.ValueType visitIntConstant(IntConstant constant) { |
| if (expectedType is w.RefType) return defaultConstant(constant); |
| if (expectedType == w.NumType.i32) { |
| b.i32_const(constant.value); |
| return w.NumType.i32; |
| } |
| b.i64_const(constant.value); |
| return w.NumType.i64; |
| } |
| |
| @override |
| w.ValueType visitDoubleConstant(DoubleConstant constant) { |
| if (expectedType is w.RefType) return defaultConstant(constant); |
| b.f64_const(constant.value); |
| return w.NumType.f64; |
| } |
| |
| @override |
| w.ValueType visitInstanceConstant(InstanceConstant constant) { |
| if (constant.classNode == translator.wasmI32Class) { |
| int value = (constant.fieldValues.values.single as IntConstant).value; |
| b.i32_const(value); |
| return w.NumType.i32; |
| } |
| if (constant.classNode == translator.wasmI64Class) { |
| int value = (constant.fieldValues.values.single as IntConstant).value; |
| b.i64_const(value); |
| return w.NumType.i64; |
| } |
| if (constant.classNode == translator.wasmF32Class) { |
| double value = |
| (constant.fieldValues.values.single as DoubleConstant).value; |
| b.f32_const(value); |
| return w.NumType.f32; |
| } |
| if (constant.classNode == translator.wasmF64Class) { |
| double value = |
| (constant.fieldValues.values.single as DoubleConstant).value; |
| b.f64_const(value); |
| return w.NumType.f64; |
| } |
| return super.visitInstanceConstant(constant); |
| } |
| } |
| |
| class ConstantCreator extends ConstantVisitor<ConstantInfo?> |
| with ConstantVisitorDefaultMixin<ConstantInfo?> { |
| final Constants constants; |
| |
| ConstantCreator(this.constants); |
| |
| Translator get translator => constants.translator; |
| Types get types => translator.types; |
| |
| Constant get _uninitializedHashBaseIndexConstant => |
| (translator.uninitializedHashBaseIndex.initializer as ConstantExpression) |
| .constant; |
| |
| ConstantInfo? ensureConstant(Constant constant) { |
| // To properly canonicalize type literal constants, we normalize the |
| // type before canonicalization. |
| if (constant is TypeLiteralConstant) { |
| DartType type = types.normalize(constant.type); |
| constant = constants._lowerTypeConstant(type); |
| } |
| |
| ConstantInfo? info = constants.constantInfo[constant]; |
| if (info == null) { |
| info = constant.accept(this); |
| if (info != null) { |
| constants.constantInfo[constant] = info; |
| } |
| } |
| return info; |
| } |
| |
| ConstantInfo createConstant( |
| Constant constant, w.RefType type, ConstantCodeGenerator generator, |
| {bool lazy = false}) { |
| assert(!type.nullable); |
| final mainModule = translator.mainModule; |
| if (lazy) { |
| // Create uninitialized global and function to initialize it. |
| final global = |
| mainModule.globals.define(w.GlobalType(type.withNullability(true))); |
| global.initializer.ref_null(w.HeapType.none); |
| global.initializer.end(); |
| w.FunctionType ftype = |
| translator.typesBuilder.defineFunction(const [], [type]); |
| final function = mainModule.functions.define(ftype, "$constant"); |
| final b2 = function.body; |
| generator(b2); |
| w.Local temp = b2.addLocal(type); |
| b2.local_tee(temp); |
| b2.global_set(global); |
| b2.local_get(temp); |
| b2.end(); |
| |
| return ConstantInfo(constant, global, function); |
| } else { |
| // Create global with the constant in its initializer. |
| assert(!constants.currentlyCreating); |
| constants.currentlyCreating = true; |
| final global = |
| mainModule.globals.define(w.GlobalType(type, mutable: false)); |
| generator(global.initializer); |
| global.initializer.end(); |
| constants.currentlyCreating = false; |
| |
| return ConstantInfo(constant, global, null); |
| } |
| } |
| |
| @override |
| ConstantInfo? defaultConstant(Constant constant) => null; |
| |
| @override |
| ConstantInfo? visitBoolConstant(BoolConstant constant) { |
| ClassInfo info = translator.classInfo[translator.boxedBoolClass]!; |
| return createConstant(constant, info.nonNullableType, (b) { |
| b.i32_const(info.classId); |
| b.i32_const(constant.value ? 1 : 0); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitIntConstant(IntConstant constant) { |
| ClassInfo info = translator.classInfo[translator.boxedIntClass]!; |
| return createConstant(constant, info.nonNullableType, (b) { |
| b.i32_const(info.classId); |
| b.i64_const(constant.value); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitDoubleConstant(DoubleConstant constant) { |
| ClassInfo info = translator.classInfo[translator.boxedDoubleClass]!; |
| return createConstant(constant, info.nonNullableType, (b) { |
| b.i32_const(info.classId); |
| b.f64_const(constant.value); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitStringConstant(StringConstant constant) { |
| if (translator.options.jsCompatibility) { |
| ClassInfo info = translator.classInfo[translator.jsStringClass]!; |
| return createConstant(constant, info.nonNullableType, (b) { |
| b.pushObjectHeaderFields(info); |
| translator.globals.readGlobal(b, |
| translator.getInternalizedStringGlobal(b.module, constant.value)); |
| b.struct_new(info.struct); |
| }); |
| } |
| bool isOneByte = constant.value.codeUnits.every((c) => c <= 255); |
| ClassInfo info = translator.classInfo[isOneByte |
| ? translator.oneByteStringClass |
| : translator.twoByteStringClass]!; |
| translator.functions.recordClassAllocation(info.classId); |
| w.RefType type = info.nonNullableType; |
| bool lazy = constant.value.length > maxArrayNewFixedLength; |
| return createConstant(constant, type, lazy: lazy, (b) { |
| w.ArrayType arrayType = |
| (info.struct.fields[FieldIndex.stringArray].type as w.RefType) |
| .heapType as w.ArrayType; |
| |
| b.pushObjectHeaderFields(info); |
| if (lazy) { |
| // Initialize string contents from passive data segment. |
| w.DataSegmentBuilder segment; |
| Uint8List bytes; |
| if (isOneByte) { |
| segment = constants.oneByteStringSegment ??= |
| translator.mainModule.dataSegments.define(); |
| bytes = Uint8List.fromList(constant.value.codeUnits); |
| } else { |
| assert(Endian.host == Endian.little); |
| segment = constants.twoByteStringSegment ??= |
| translator.mainModule.dataSegments.define(); |
| bytes = Uint16List.fromList(constant.value.codeUnits) |
| .buffer |
| .asUint8List(); |
| } |
| int offset = segment.length; |
| segment.append(bytes); |
| b.i32_const(offset); |
| b.i32_const(constant.value.length); |
| b.array_new_data(arrayType, segment); |
| } else { |
| // Initialize string contents from i32 constants on the stack. |
| for (int charCode in constant.value.codeUnits) { |
| b.i32_const(charCode); |
| } |
| b.array_new_fixed(arrayType, constant.value.length); |
| } |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitInstanceConstant(InstanceConstant constant) { |
| Class cls = constant.classNode; |
| if (cls == translator.wasmArrayClass) { |
| return _makeWasmArrayLiteral(constant, mutable: true); |
| } |
| if (cls == translator.immutableWasmArrayClass) { |
| return _makeWasmArrayLiteral(constant, mutable: false); |
| } |
| |
| ClassInfo info = translator.classInfo[cls]!; |
| translator.functions.recordClassAllocation(info.classId); |
| w.RefType type = info.nonNullableType; |
| |
| // Collect sub-constants for field values. |
| const int baseFieldCount = 2; |
| int fieldCount = info.struct.fields.length; |
| List<Constant?> subConstants = List.filled(fieldCount, null); |
| bool lazy = false; |
| constant.fieldValues.forEach((reference, subConstant) { |
| int index = translator.fieldIndex[reference.asField]!; |
| assert(subConstants[index] == null); |
| subConstants[index] = subConstant; |
| lazy |= ensureConstant(subConstant)?.isLazy ?? false; |
| }); |
| |
| // Collect sub-constants for type arguments. |
| Map<TypeParameter, DartType> substitution = {}; |
| List<DartType> args = constant.typeArguments; |
| while (true) { |
| for (int i = 0; i < cls.typeParameters.length; i++) { |
| TypeParameter parameter = cls.typeParameters[i]; |
| DartType arg = substitute(args[i], substitution); |
| substitution[parameter] = arg; |
| int index = translator.typeParameterIndex[parameter]!; |
| Constant typeArgConstant = constants._lowerTypeConstant(arg); |
| subConstants[index] = typeArgConstant; |
| ensureConstant(typeArgConstant); |
| } |
| Supertype? supertype = cls.supertype; |
| if (supertype == null) break; |
| cls = supertype.classNode; |
| args = supertype.typeArguments; |
| } |
| |
| return createConstant(constant, type, lazy: lazy, (b) { |
| b.pushObjectHeaderFields(info); |
| for (int i = baseFieldCount; i < fieldCount; i++) { |
| Constant subConstant = subConstants[i]!; |
| constants.instantiateConstant( |
| b, subConstant, info.struct.fields[i].type.unpacked); |
| } |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| ConstantInfo? _makeWasmArrayLiteral(InstanceConstant constant, |
| {required bool mutable}) { |
| w.ArrayType arrayType = translator |
| .arrayTypeForDartType(constant.typeArguments.single, mutable: mutable); |
| w.ValueType elementType = arrayType.elementType.type.unpacked; |
| |
| List<Constant> elements = |
| (constant.fieldValues.values.single as ListConstant).entries; |
| final tooLargeForArrayNewFixed = elements.length > maxArrayNewFixedLength; |
| bool lazy = tooLargeForArrayNewFixed; |
| for (Constant element in elements) { |
| lazy |= ensureConstant(element)?.isLazy ?? false; |
| } |
| |
| if (tooLargeForArrayNewFixed && !mutable) { |
| throw Exception('Cannot allocate immutable wasm array of size ' |
| '$tooLargeForArrayNewFixed'); |
| } |
| |
| return createConstant(constant, w.RefType.def(arrayType, nullable: false), |
| lazy: lazy, (b) { |
| if (tooLargeForArrayNewFixed) { |
| // We will initialize the array with one of the elements (using |
| // `array.new`) and update the fields. |
| // |
| // For the initial element pick the one that occurs the most to save |
| // some work when the array has duplicates. |
| final Map<Constant, int> occurrences = {}; |
| for (final element in elements) { |
| occurrences.update(element, (i) => i + 1, ifAbsent: () => 1); |
| } |
| |
| var initialElement = elements[0]; |
| var initialElementOccurrences = 1; |
| for (final entry in occurrences.entries) { |
| if (entry.value > initialElementOccurrences) { |
| initialElementOccurrences = entry.value; |
| initialElement = entry.key; |
| } |
| } |
| |
| w.Local arrayLocal = |
| b.addLocal(w.RefType.def(arrayType, nullable: false)); |
| constants.instantiateConstant(b, initialElement, elementType); |
| b.i32_const(elements.length); |
| b.array_new(arrayType); |
| b.local_set(arrayLocal); |
| |
| for (int i = 0; i < elements.length;) { |
| // If it's the same as initial element, nothing to do. |
| final value = elements[i++]; |
| if (value == initialElement) continue; |
| |
| // Find out how many times the current element repeats. |
| final int startInclusive = i - 1; |
| while (i < elements.length && elements[i] == value) { |
| i++; |
| } |
| final int endExclusive = i; |
| final int count = endExclusive - startInclusive; |
| |
| b.local_get(arrayLocal); |
| b.i32_const(startInclusive); |
| constants.instantiateConstant(b, value, elementType); |
| if (count > 1) { |
| b.i32_const(count); |
| b.array_fill(arrayType); |
| } else { |
| b.array_set(arrayType); |
| } |
| } |
| b.local_get(arrayLocal); |
| } else { |
| for (Constant element in elements) { |
| constants.instantiateConstant(b, element, elementType); |
| } |
| b.array_new_fixed(arrayType, elements.length); |
| } |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitListConstant(ListConstant constant) { |
| Constant typeArgConstant = |
| constants._lowerTypeConstant(constant.typeArgument); |
| ensureConstant(typeArgConstant); |
| bool lazy = constant.entries.length > maxArrayNewFixedLength; |
| for (Constant subConstant in constant.entries) { |
| lazy |= ensureConstant(subConstant)?.isLazy ?? false; |
| } |
| |
| ClassInfo info = translator.classInfo[translator.immutableListClass]!; |
| translator.functions.recordClassAllocation(info.classId); |
| w.RefType type = info.nonNullableType; |
| return createConstant(constant, type, lazy: lazy, (b) { |
| w.ArrayType arrayType = translator.listArrayType; |
| w.ValueType elementType = arrayType.elementType.type.unpacked; |
| int length = constant.entries.length; |
| b.pushObjectHeaderFields(info); |
| constants.instantiateConstant( |
| b, typeArgConstant, constants.typeInfo.nullableType); |
| b.i64_const(length); |
| if (lazy) { |
| // Allocate array and set each entry to the corresponding sub-constant. |
| w.Local arrayLocal = |
| b.addLocal(w.RefType.def(arrayType, nullable: false)); |
| b.i32_const(length); |
| b.array_new_default(arrayType); |
| b.local_set(arrayLocal); |
| for (int i = 0; i < length; i++) { |
| b.local_get(arrayLocal); |
| b.i32_const(i); |
| constants.instantiateConstant(b, constant.entries[i], elementType); |
| b.array_set(arrayType); |
| } |
| b.local_get(arrayLocal); |
| } else { |
| // Push all sub-constants on the stack and initialize array from them. |
| for (int i = 0; i < length; i++) { |
| constants.instantiateConstant(b, constant.entries[i], elementType); |
| } |
| b.array_new_fixed(arrayType, length); |
| } |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitMapConstant(MapConstant constant) { |
| final listElements = List.generate(constant.entries.length * 2, (i) { |
| ConstantMapEntry entry = constant.entries[i >> 1]; |
| return i.isEven ? entry.key : entry.value; |
| }); |
| |
| final instanceConstant = |
| InstanceConstant(translator.immutableMapClass.reference, [ |
| constant.keyType, |
| constant.valueType |
| ], { |
| // _index = _uninitializedHashBaseIndex |
| translator.hashFieldBaseIndexField.fieldReference: |
| _uninitializedHashBaseIndexConstant, |
| |
| // _hashMask |
| translator.hashFieldBaseHashMaskField.fieldReference: IntConstant(0), |
| |
| // _data |
| translator.hashFieldBaseDataField.fieldReference: |
| InstanceConstant(translator.wasmArrayClass.reference, [ |
| translator.coreTypes.objectNullableRawType |
| ], { |
| translator.wasmArrayValueField.fieldReference: ListConstant( |
| translator.coreTypes.objectNullableRawType, listElements) |
| }), |
| |
| // _usedData |
| translator.hashFieldBaseUsedDataField.fieldReference: |
| IntConstant(listElements.length), |
| |
| // _deletedKeys |
| translator.hashFieldBaseDeletedKeysField.fieldReference: IntConstant(0), |
| }); |
| |
| return ensureConstant(instanceConstant); |
| } |
| |
| @override |
| ConstantInfo? visitSetConstant(SetConstant constant) { |
| final instanceConstant = |
| InstanceConstant(translator.immutableSetClass.reference, [ |
| constant.typeArgument |
| ], { |
| // _index = _uninitializedHashBaseIndex |
| translator.hashFieldBaseIndexField.fieldReference: |
| _uninitializedHashBaseIndexConstant, |
| |
| // _hashMask |
| translator.hashFieldBaseHashMaskField.fieldReference: IntConstant(0), |
| |
| // _data |
| translator.hashFieldBaseDataField.fieldReference: |
| InstanceConstant(translator.wasmArrayClass.reference, [ |
| translator.coreTypes.objectNullableRawType |
| ], { |
| translator.wasmArrayValueField.fieldReference: ListConstant( |
| translator.coreTypes.objectNullableRawType, constant.entries) |
| }), |
| |
| // _usedData |
| translator.hashFieldBaseUsedDataField.fieldReference: |
| IntConstant(constant.entries.length), |
| |
| // _deletedKeys |
| translator.hashFieldBaseDeletedKeysField.fieldReference: IntConstant(0), |
| }); |
| |
| return ensureConstant(instanceConstant); |
| } |
| |
| @override |
| ConstantInfo? visitStaticTearOffConstant(StaticTearOffConstant constant) { |
| Procedure member = constant.targetReference.asProcedure; |
| Constant functionTypeConstant = |
| constants._lowerTypeConstant(translator.getTearOffType(member)); |
| ensureConstant(functionTypeConstant); |
| ClosureImplementation closure = translator.getTearOffClosure(member); |
| w.StructType struct = closure.representation.closureStruct; |
| w.RefType type = w.RefType.def(struct, nullable: false); |
| |
| // The vtable for the target will be stored on a global in the target's |
| // module. |
| final isLazy = !translator |
| .isMainModule(translator.moduleForReference(constant.targetReference)); |
| // The dummy struct must be declared before the constant global so that the |
| // constant's initializer can reference it. |
| final dummyStructGlobal = translator |
| .getDummyValuesCollectorForModule(translator.mainModule) |
| .dummyStructGlobal; |
| return createConstant(constant, type, (b) { |
| ClassInfo info = translator.closureInfo; |
| translator.functions.recordClassAllocation(info.classId); |
| |
| b.pushObjectHeaderFields(info); |
| translator.globals.readGlobal(b, dummyStructGlobal); // Dummy context |
| translator.globals.readGlobal(b, closure.vtable); |
| constants.instantiateConstant( |
| b, functionTypeConstant, types.nonNullableTypeType); |
| b.struct_new(struct); |
| }, lazy: isLazy); |
| } |
| |
| @override |
| ConstantInfo? visitInstantiationConstant(InstantiationConstant constant) { |
| TearOffConstant tearOffConstant = |
| constant.tearOffConstant as TearOffConstant; |
| List<ConstantInfo> types = constant.types |
| .map((c) => ensureConstant(constants._lowerTypeConstant(c))!) |
| .toList(); |
| Procedure tearOffProcedure = tearOffConstant.targetReference.asProcedure; |
| FunctionType tearOffFunctionType = |
| translator.getTearOffType(tearOffProcedure); |
| FunctionType instantiatedFunctionType = |
| FunctionTypeInstantiator.instantiate( |
| tearOffFunctionType, constant.types); |
| Constant functionTypeConstant = |
| constants._lowerTypeConstant(instantiatedFunctionType); |
| ensureConstant(functionTypeConstant); |
| ClosureImplementation tearOffClosure = |
| translator.getTearOffClosure(tearOffProcedure); |
| int positionalCount = tearOffConstant.function.positionalParameters.length; |
| List<String> names = |
| tearOffConstant.function.namedParameters.map((p) => p.name!).toList(); |
| ClosureRepresentation instantiationOfTearOffRepresentation = translator |
| .closureLayouter |
| .getClosureRepresentation(0, positionalCount, names)!; |
| ClosureRepresentation tearOffRepresentation = translator.closureLayouter |
| .getClosureRepresentation(types.length, positionalCount, names)!; |
| w.StructType struct = instantiationOfTearOffRepresentation.closureStruct; |
| w.RefType type = w.RefType.def(struct, nullable: false); |
| |
| final tearOffConstantInfo = ensureConstant(tearOffConstant)!; |
| |
| w.BaseFunction makeDynamicCallEntry() { |
| final function = translator.mainModule.functions.define( |
| translator.dynamicCallVtableEntryFunctionType, "dynamic call entry"); |
| |
| final b = function.body; |
| |
| final closureLocal = function.locals[0]; |
| final typeArgsListLocal = function.locals[1]; // empty |
| final posArgsListLocal = function.locals[2]; |
| final namedArgsListLocal = function.locals[3]; |
| |
| b.local_get(closureLocal); |
| final InstanceConstant typeArgs = constants.makeTypeArray(constant.types); |
| constants.instantiateConstant(b, typeArgs, typeArgsListLocal.type); |
| b.local_get(posArgsListLocal); |
| b.local_get(namedArgsListLocal); |
| translator.callFunction(tearOffClosure.dynamicCallEntry, b); |
| b.end(); |
| |
| return function; |
| } |
| |
| // Dynamic call entry needs to be created first (before `createConstant`) |
| // as it needs to create a constant for the type list, and we cannot create |
| // a constant while creating another one. |
| final w.BaseFunction dynamicCallEntry = makeDynamicCallEntry(); |
| |
| final lazy = tearOffConstantInfo.isLazy; |
| |
| return createConstant(constant, type, lazy: lazy, (b) { |
| ClassInfo info = translator.closureInfo; |
| translator.functions.recordClassAllocation(info.classId); |
| |
| void declareAndAddRefFunc(w.BaseFunction function) { |
| // If the constant is lazy the body will be in a function rather than a |
| // global. In order for a function to use a ref.func, the function must |
| // be declared in a global (or via the element section). |
| if (lazy) { |
| final global = b.module.globals |
| .define(w.GlobalType(w.RefType(function.type, nullable: false))); |
| global.initializer |
| ..ref_func(function) |
| ..end(); |
| b.global_get(global); |
| } else { |
| b.ref_func(function); |
| } |
| } |
| |
| w.BaseFunction makeTrampoline( |
| w.FunctionType signature, w.BaseFunction tearOffFunction) { |
| assert(tearOffFunction.type.inputs.length == |
| signature.inputs.length + types.length); |
| final function = b.module.functions |
| .define(signature, "instantiation constant trampoline"); |
| final b2 = function.body; |
| b2.local_get(function.locals[0]); |
| for (ConstantInfo typeInfo in types) { |
| typeInfo.readConstant(translator, b2); |
| } |
| for (int i = 1; i < signature.inputs.length; i++) { |
| b2.local_get(function.locals[i]); |
| } |
| translator.callFunction(tearOffFunction, b2); |
| b2.end(); |
| return function; |
| } |
| |
| void fillVtableEntry(int posArgCount, NameCombination nameCombination) { |
| final fieldIndex = instantiationOfTearOffRepresentation |
| .fieldIndexForSignature(posArgCount, nameCombination.names); |
| final signature = |
| instantiationOfTearOffRepresentation.getVtableFieldType(fieldIndex); |
| |
| w.BaseFunction function; |
| if (nameCombination.names.isNotEmpty && |
| !tearOffRepresentation.nameCombinations.contains(nameCombination)) { |
| // This name combination only has |
| // - non-generic closure / non-generic tear-off definitions |
| // - non-generic callers |
| // => We make a dummy entry which is unreachable. |
| function = translator |
| .getDummyValuesCollectorForModule(b.module) |
| .getDummyFunction(signature); |
| } else { |
| final int tearOffFieldIndex = tearOffRepresentation |
| .fieldIndexForSignature(posArgCount, nameCombination.names); |
| w.BaseFunction tearOffFunction = tearOffClosure.functions[ |
| tearOffFieldIndex - tearOffRepresentation.vtableBaseIndex]; |
| if (translator |
| .getDummyValuesCollectorForModule(b.module) |
| .isDummyFunction(tearOffFunction)) { |
| // This name combination may not exist for the target, but got |
| // clustered together with other name combinations that do exist. |
| // => We make a dummy entry which is unreachable. |
| function = translator |
| .getDummyValuesCollectorForModule(b.module) |
| .getDummyFunction(signature); |
| } else { |
| function = makeTrampoline(signature, tearOffFunction); |
| } |
| } |
| declareAndAddRefFunc(function); |
| } |
| |
| void makeVtable() { |
| declareAndAddRefFunc(dynamicCallEntry); |
| assert(!instantiationOfTearOffRepresentation.isGeneric); |
| for (int posArgCount = 0; |
| posArgCount <= positionalCount; |
| posArgCount++) { |
| fillVtableEntry(posArgCount, NameCombination(const [])); |
| } |
| for (NameCombination combination |
| in instantiationOfTearOffRepresentation.nameCombinations) { |
| fillVtableEntry(positionalCount, combination); |
| } |
| b.struct_new(instantiationOfTearOffRepresentation.vtableStruct); |
| } |
| |
| b.pushObjectHeaderFields(info); |
| |
| // Context is not used by the vtable functions, but it's needed for |
| // closure equality checks to work (`_Closure._equals`). |
| tearOffConstantInfo.readConstant(translator, b); |
| |
| for (final ty in types) { |
| ty.readConstant(translator, b); |
| } |
| b.struct_new(tearOffRepresentation.instantiationContextStruct!); |
| |
| makeVtable(); |
| constants.instantiateConstant( |
| b, functionTypeConstant, this.types.nonNullableTypeType); |
| b.struct_new(struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitTypeLiteralConstant(TypeLiteralConstant constant) { |
| throw 'Unreachable - should have been lowered'; |
| } |
| |
| @override |
| ConstantInfo? visitSymbolConstant(SymbolConstant constant) { |
| ClassInfo info = translator.classInfo[translator.symbolClass]!; |
| translator.functions.recordClassAllocation(info.classId); |
| w.RefType stringType = translator |
| .classInfo[translator.coreTypes.stringClass]!.repr.nonNullableType; |
| StringConstant nameConstant = StringConstant(constant.name); |
| bool lazy = ensureConstant(nameConstant)?.isLazy ?? false; |
| return createConstant(constant, info.nonNullableType, lazy: lazy, (b) { |
| b.pushObjectHeaderFields(info); |
| constants.instantiateConstant(b, nameConstant, stringType); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitRecordConstant(RecordConstant constant) { |
| final ClassInfo recordClassInfo = |
| translator.getRecordClassInfo(constant.recordType); |
| translator.functions.recordClassAllocation(recordClassInfo.classId); |
| |
| final List<Constant> arguments = constant.positional.toList(); |
| arguments.addAll(constant.named.values); |
| |
| bool lazy = false; |
| for (Constant argument in arguments) { |
| lazy |= ensureConstant(argument)?.isLazy ?? false; |
| } |
| |
| return createConstant(constant, recordClassInfo.nonNullableType, lazy: lazy, |
| (b) { |
| b.pushObjectHeaderFields(recordClassInfo); |
| for (Constant argument in arguments) { |
| constants.instantiateConstant( |
| b, argument, translator.topInfo.nullableType); |
| } |
| b.struct_new(recordClassInfo.struct); |
| }); |
| } |
| } |
