| // 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:math'; |
| import 'dart:typed_data'; |
| |
| import 'package:dart2wasm/class_info.dart'; |
| import 'package:dart2wasm/closures.dart'; |
| import 'package:dart2wasm/param_info.dart'; |
| import 'package:dart2wasm/translator.dart'; |
| import 'package:dart2wasm/types.dart'; |
| |
| import 'package:kernel/ast.dart'; |
| import 'package:kernel/type_algebra.dart' |
| show FunctionTypeInstantiator, substitute; |
| |
| import 'package:wasm_builder/wasm_builder.dart' as w; |
| |
| 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; |
| } |
| |
| typedef ConstantCodeGenerator = void Function( |
| w.FunctionBuilder?, 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]!; |
| |
| bool currentlyCreating = false; |
| |
| Constants(this.translator) {} |
| |
| w.ModuleBuilder get m => translator.m; |
| |
| /// Makes a type list [ListConstant]. |
| ListConstant makeTypeList(Iterable<DartType> types) => ListConstant( |
| InterfaceType(translator.typeClass, Nullability.nonNullable), |
| types.map((t) => TypeLiteralConstant(t)).toList()); |
| |
| InstanceConstant makeTypeArray(Iterable<DartType> types) => |
| InstanceConstant(translator.wasmObjectArrayClass.reference, [ |
| InterfaceType(translator.typeClass, Nullability.nonNullable) |
| ], { |
| translator.wasmObjectArrayValueField.fieldReference: makeTypeList(types) |
| }); |
| |
| /// Makes a `_NamedParameter` [InstanceConstant]. |
| InstanceConstant makeNamedParameterConstant(NamedType n) { |
| Class namedParameter = translator.namedParameterClass; |
| assert(namedParameter.fields[0].name.text == 'name' && |
| namedParameter.fields[1].name.text == 'type' && |
| namedParameter.fields[2].name.text == 'isRequired'); |
| Reference namedParameterName = namedParameter.fields[0].fieldReference; |
| Reference namedParameterType = namedParameter.fields[1].fieldReference; |
| Reference namedParameterIsRequired = |
| namedParameter.fields[2].fieldReference; |
| return InstanceConstant(namedParameter.reference, [], { |
| namedParameterName: StringConstant(n.name), |
| namedParameterType: TypeLiteralConstant(n.type), |
| namedParameterIsRequired: BoolConstant(n.isRequired) |
| }); |
| } |
| |
| /// Makes a [ListConstant] of `_NamedParameters` to initialize a [FunctionType]. |
| ListConstant makeNamedParametersList(FunctionType type) => ListConstant( |
| translator.types.namedParameterType, |
| type.namedParameters.map(makeNamedParameterConstant).toList()); |
| |
| /// 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.BaseFunction? function, w.InstructionsBuilder b, |
| Constant constant, w.ValueType expectedType) { |
| if (expectedType == translator.voidMarker) return; |
| ConstantInstantiator(this, function, b, expectedType).instantiate(constant); |
| } |
| } |
| |
| class ConstantInstantiator extends ConstantVisitor<w.ValueType> |
| with ConstantVisitorDefaultMixin<w.ValueType> { |
| final Constants constants; |
| final w.BaseFunction? function; |
| final w.InstructionsBuilder b; |
| final w.ValueType expectedType; |
| |
| ConstantInstantiator( |
| this.constants, this.function, this.b, this.expectedType); |
| |
| Translator get translator => constants.translator; |
| w.ModuleBuilder get m => translator.m; |
| |
| 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"); |
| b.unreachable(); |
| } |
| } |
| } |
| |
| @override |
| w.ValueType defaultConstant(Constant constant) { |
| ConstantInfo info = ConstantCreator(constants).ensureConstant(constant)!; |
| if (info.isLazy) { |
| // Lazily initialized constant. |
| w.ValueType type = info.global.type.type.withNullability(false); |
| w.Label done = b.block(const [], [type]); |
| b.global_get(info.global); |
| b.br_on_non_null(done); |
| b.call(info.function!); |
| b.end(); |
| return type; |
| } else { |
| // Constant initialized eagerly in a global initializer. |
| b.global_get(info.global); |
| return info.global.type.type; |
| } |
| } |
| |
| @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.globals.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); |
| 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; |
| w.ModuleBuilder get m => constants.m; |
| |
| 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); |
| if (!identical(type, constant.type)) { |
| constant = TypeLiteralConstant(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); |
| if (lazy) { |
| // Create uninitialized global and function to initialize it. |
| final global = m.globals.define(w.GlobalType(type.withNullability(true))); |
| global.initializer.ref_null(w.HeapType.none); |
| global.initializer.end(); |
| w.FunctionType ftype = m.types.defineFunction(const [], [type]); |
| final function = m.functions.define(ftype, "$constant"); |
| generator(function, function.body); |
| w.Local temp = function.addLocal(type); |
| final b2 = function.body; |
| 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 = m.globals.define(w.GlobalType(type, mutable: false)); |
| generator(null, 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, (function, 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, (function, 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, (function, 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, (function, b) { |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.global_get(translator.getInternalizedStringGlobal(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.allocateClass(info.classId); |
| w.RefType type = info.nonNullableType; |
| bool lazy = constant.value.length > maxArrayNewFixedLength; |
| return createConstant(constant, type, lazy: lazy, (function, b) { |
| w.ArrayType arrayType = |
| (info.struct.fields[FieldIndex.stringArray].type as w.RefType) |
| .heapType as w.ArrayType; |
| |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| if (lazy) { |
| // Initialize string contents from passive data segment. |
| w.DataSegmentBuilder segment; |
| Uint8List bytes; |
| if (isOneByte) { |
| segment = constants.oneByteStringSegment ??= m.dataSegments.define(); |
| bytes = Uint8List.fromList(constant.value.codeUnits); |
| } else { |
| assert(Endian.host == Endian.little); |
| segment = constants.twoByteStringSegment ??= m.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.wasmObjectArrayClass) { |
| return _makeWasmArrayLiteral(constant); |
| } |
| |
| ClassInfo info = translator.classInfo[cls]!; |
| translator.functions.allocateClass(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 = TypeLiteralConstant(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, (function, b) { |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| for (int i = baseFieldCount; i < fieldCount; i++) { |
| Constant subConstant = subConstants[i]!; |
| constants.instantiateConstant( |
| function, b, subConstant, info.struct.fields[i].type.unpacked); |
| } |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| ConstantInfo? _makeWasmArrayLiteral(InstanceConstant constant) { |
| w.ArrayType arrayType = |
| translator.arrayTypeForDartType(constant.typeArguments.single); |
| w.ValueType elementType = arrayType.elementType.type.unpacked; |
| |
| List<Constant> elements = |
| (constant.fieldValues.values.single as ListConstant).entries; |
| bool lazy = false; |
| for (Constant element in elements) { |
| lazy |= ensureConstant(element)?.isLazy ?? false; |
| } |
| |
| return createConstant(constant, w.RefType.def(arrayType, nullable: false), |
| lazy: lazy, (function, b) { |
| for (Constant element in elements) { |
| constants.instantiateConstant(function, b, element, elementType); |
| } |
| b.array_new_fixed(arrayType, elements.length); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitListConstant(ListConstant constant) { |
| Constant typeArgConstant = TypeLiteralConstant(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.allocateClass(info.classId); |
| w.RefType type = info.nonNullableType; |
| return createConstant(constant, type, lazy: lazy, (function, b) { |
| w.ArrayType arrayType = translator.listArrayType; |
| w.ValueType elementType = arrayType.elementType.type.unpacked; |
| int length = constant.entries.length; |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| constants.instantiateConstant( |
| function, 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 = |
| function!.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( |
| function, 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( |
| function, b, constant.entries[i], elementType); |
| } |
| b.array_new_fixed(arrayType, length); |
| } |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitMapConstant(MapConstant constant) { |
| Constant keyTypeConstant = TypeLiteralConstant(constant.keyType); |
| ensureConstant(keyTypeConstant); |
| Constant valueTypeConstant = TypeLiteralConstant(constant.valueType); |
| ensureConstant(valueTypeConstant); |
| List<Constant> dataElements = |
| List.generate(constant.entries.length * 2, (i) { |
| ConstantMapEntry entry = constant.entries[i >> 1]; |
| return i.isEven ? entry.key : entry.value; |
| }); |
| ListConstant dataList = ListConstant(const DynamicType(), dataElements); |
| bool lazy = ensureConstant(dataList)?.isLazy ?? false; |
| |
| ClassInfo info = translator.classInfo[translator.immutableMapClass]!; |
| translator.functions.allocateClass(info.classId); |
| w.RefType type = info.nonNullableType; |
| return createConstant(constant, type, lazy: lazy, (function, b) { |
| w.RefType indexType = |
| info.struct.fields[FieldIndex.hashBaseIndex].type as w.RefType; |
| w.RefType dataType = |
| info.struct.fields[FieldIndex.hashBaseData].type as w.RefType; |
| |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.ref_null(indexType.heapType); // _index |
| b.i64_const(_computeHashMask(constant.entries.length)); // _hashMask |
| constants.instantiateConstant(function, b, dataList, dataType); // _data |
| b.i64_const(dataElements.length); // _usedData |
| b.i64_const(0); // _deletedKeys |
| constants.instantiateConstant( |
| function, b, keyTypeConstant, constants.typeInfo.nullableType); |
| constants.instantiateConstant( |
| function, b, valueTypeConstant, constants.typeInfo.nullableType); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitSetConstant(SetConstant constant) { |
| Constant elementTypeConstant = TypeLiteralConstant(constant.typeArgument); |
| ensureConstant(elementTypeConstant); |
| ListConstant dataList = ListConstant(const DynamicType(), constant.entries); |
| bool lazy = ensureConstant(dataList)?.isLazy ?? false; |
| |
| ClassInfo info = translator.classInfo[translator.immutableSetClass]!; |
| translator.functions.allocateClass(info.classId); |
| w.RefType type = info.nonNullableType; |
| return createConstant(constant, type, lazy: lazy, (function, b) { |
| w.RefType indexType = |
| info.struct.fields[FieldIndex.hashBaseIndex].type as w.RefType; |
| w.RefType dataType = |
| info.struct.fields[FieldIndex.hashBaseData].type as w.RefType; |
| |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.ref_null(indexType.heapType); // _index |
| b.i64_const(_computeHashMask(constant.entries.length)); // _hashMask |
| constants.instantiateConstant(function, b, dataList, dataType); // _data |
| b.i64_const(constant.entries.length); // _usedData |
| b.i64_const(0); // _deletedKeys |
| constants.instantiateConstant( |
| function, b, elementTypeConstant, constants.typeInfo.nullableType); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| int _computeHashMask(int entries) { |
| // This computation of the hash mask follows the computations in |
| // [_ImmutableLinkedHashMapMixin._createIndex], |
| // [_ImmutableLinkedHashSetMixin._createIndex] and |
| // [_HashBase._indexSizeToHashMask]. |
| const int initialIndexSize = 8; |
| final int indexSize = max(entries * 2, initialIndexSize); |
| final int hashMask = (1 << (31 - (indexSize - 1).bitLength)) - 1; |
| return hashMask; |
| } |
| |
| @override |
| ConstantInfo? visitStaticTearOffConstant(StaticTearOffConstant constant) { |
| Procedure member = constant.targetReference.asProcedure; |
| Constant functionTypeConstant = |
| TypeLiteralConstant(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); |
| return createConstant(constant, type, (function, b) { |
| ClassInfo info = translator.closureInfo; |
| translator.functions.allocateClass(info.classId); |
| |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.global_get(translator.globals.dummyStructGlobal); // Dummy context |
| b.global_get(closure.vtable); |
| constants.instantiateConstant( |
| function, b, functionTypeConstant, this.types.nonNullableTypeType); |
| b.struct_new(struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitInstantiationConstant(InstantiationConstant constant) { |
| TearOffConstant tearOffConstant = |
| constant.tearOffConstant as TearOffConstant; |
| List<ConstantInfo> types = constant.types |
| .map((c) => ensureConstant(TypeLiteralConstant(c))!) |
| .toList(); |
| Procedure tearOffProcedure = tearOffConstant.targetReference.asProcedure; |
| FunctionType tearOffFunctionType = |
| translator.getTearOffType(tearOffProcedure); |
| FunctionType instantiatedFunctionType = |
| FunctionTypeInstantiator.instantiate( |
| tearOffFunctionType, constant.types); |
| Constant functionTypeConstant = |
| TypeLiteralConstant(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 representation = translator.closureLayouter |
| .getClosureRepresentation(0, positionalCount, names)!; |
| ClosureRepresentation instantiationRepresentation = translator |
| .closureLayouter |
| .getClosureRepresentation(types.length, positionalCount, names)!; |
| w.StructType struct = representation.closureStruct; |
| w.RefType type = w.RefType.def(struct, nullable: false); |
| |
| final tearOffConstantInfo = ensureConstant(tearOffConstant)!; |
| |
| w.BaseFunction makeDynamicCallEntry() { |
| final function = m.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 ListConstant typeArgs = constants.makeTypeList(constant.types); |
| constants.instantiateConstant( |
| function, b, typeArgs, typeArgsListLocal.type); |
| b.local_get(posArgsListLocal); |
| b.local_get(namedArgsListLocal); |
| b.call(tearOffClosure.dynamicCallEntry); |
| 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(); |
| |
| return createConstant(constant, type, (function, b) { |
| ClassInfo info = translator.closureInfo; |
| translator.functions.allocateClass(info.classId); |
| |
| w.BaseFunction makeTrampoline( |
| w.FunctionType signature, w.BaseFunction tearOffFunction) { |
| assert(tearOffFunction.type.inputs.length == |
| signature.inputs.length + types.length); |
| final function = |
| m.functions.define(signature, "instantiation constant trampoline"); |
| final b = function.body; |
| b.local_get(function.locals[0]); |
| for (ConstantInfo typeInfo in types) { |
| b.global_get(typeInfo.global); |
| } |
| for (int i = 1; i < signature.inputs.length; i++) { |
| b.local_get(function.locals[i]); |
| } |
| b.call(tearOffFunction); |
| b.end(); |
| return function; |
| } |
| |
| void fillVtableEntry(int posArgCount, List<String> argNames) { |
| int fieldIndex = |
| representation.fieldIndexForSignature(posArgCount, argNames); |
| int tearOffFieldIndex = tearOffClosure.representation |
| .fieldIndexForSignature(posArgCount, argNames); |
| |
| w.FunctionType signature = |
| representation.getVtableFieldType(fieldIndex); |
| w.BaseFunction tearOffFunction = tearOffClosure.functions[ |
| tearOffFieldIndex - tearOffClosure.representation.vtableBaseIndex]; |
| w.BaseFunction function = |
| translator.globals.isDummyFunction(tearOffFunction) |
| ? translator.globals.getDummyFunction(signature) |
| : makeTrampoline(signature, tearOffFunction); |
| b.ref_func(function); |
| } |
| |
| void makeVtable() { |
| b.ref_func(dynamicCallEntry); |
| if (representation.isGeneric) { |
| b.ref_func(representation.instantiationFunction); |
| } |
| for (int posArgCount = 0; |
| posArgCount <= positionalCount; |
| posArgCount++) { |
| fillVtableEntry(posArgCount, const []); |
| } |
| for (NameCombination combination in representation.nameCombinations) { |
| fillVtableEntry(positionalCount, combination.names); |
| } |
| b.struct_new(representation.vtableStruct); |
| } |
| |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| |
| // Context is not used by the vtable functions, but it's needed for |
| // closure equality checks to work (`_Closure._equals`). |
| b.global_get(tearOffConstantInfo.global); |
| for (final ty in types) { |
| b.global_get(ty.global); |
| } |
| b.struct_new(instantiationRepresentation.instantiationContextStruct!); |
| |
| makeVtable(); |
| constants.instantiateConstant( |
| function, b, functionTypeConstant, this.types.nonNullableTypeType); |
| b.struct_new(struct); |
| }); |
| } |
| |
| ConstantInfo? _makeInterfaceType( |
| TypeLiteralConstant constant, InterfaceType type, ClassInfo info) { |
| InstanceConstant typeArgs = constants.makeTypeArray(type.typeArguments); |
| ensureConstant(typeArgs); |
| return createConstant(constant, info.nonNullableType, (function, b) { |
| ClassInfo typeInfo = translator.classInfo[type.classNode]!; |
| w.ValueType typeArrayExpectedType = info |
| .struct.fields[FieldIndex.interfaceTypeTypeArguments].type.unpacked; |
| |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.i32_const(types.encodedNullability(type)); |
| b.i64_const(typeInfo.classId); |
| constants.instantiateConstant( |
| function, b, typeArgs, typeArrayExpectedType); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| ConstantInfo? _makeFutureOrType( |
| TypeLiteralConstant constant, FutureOrType type, ClassInfo info) { |
| TypeLiteralConstant typeArgument = TypeLiteralConstant(type.typeArgument); |
| ensureConstant(typeArgument); |
| return createConstant(constant, info.nonNullableType, (function, b) { |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.i32_const(types.encodedNullability(type)); |
| constants.instantiateConstant( |
| function, b, typeArgument, types.nonNullableTypeType); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| ConstantInfo? _makeFunctionType( |
| TypeLiteralConstant constant, FunctionType type, ClassInfo info) { |
| int typeParameterOffset = types.computeFunctionTypeParameterOffset(type); |
| ListConstant typeParameterBoundsConstant = |
| constants.makeTypeList(type.typeParameters.map((p) => p.bound)); |
| ListConstant typeParameterDefaultsConstant = |
| constants.makeTypeList(type.typeParameters.map((p) => p.defaultType)); |
| TypeLiteralConstant returnTypeConstant = |
| TypeLiteralConstant(type.returnType); |
| ListConstant positionalParametersConstant = |
| constants.makeTypeList(type.positionalParameters); |
| IntConstant requiredParameterCountConstant = |
| IntConstant(type.requiredParameterCount); |
| ListConstant namedParametersConstant = |
| constants.makeNamedParametersList(type); |
| ensureConstant(typeParameterBoundsConstant); |
| ensureConstant(typeParameterDefaultsConstant); |
| ensureConstant(returnTypeConstant); |
| ensureConstant(positionalParametersConstant); |
| ensureConstant(requiredParameterCountConstant); |
| ensureConstant(namedParametersConstant); |
| return createConstant(constant, info.nonNullableType, (function, b) { |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.i32_const(types.encodedNullability(type)); |
| b.i64_const(typeParameterOffset); |
| constants.instantiateConstant( |
| function, b, typeParameterBoundsConstant, types.typeListExpectedType); |
| constants.instantiateConstant(function, b, typeParameterDefaultsConstant, |
| types.typeListExpectedType); |
| constants.instantiateConstant( |
| function, b, returnTypeConstant, types.nonNullableTypeType); |
| constants.instantiateConstant(function, b, positionalParametersConstant, |
| types.typeListExpectedType); |
| constants.instantiateConstant( |
| function, b, requiredParameterCountConstant, w.NumType.i64); |
| constants.instantiateConstant(function, b, namedParametersConstant, |
| types.namedParametersExpectedType); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitTypeLiteralConstant(TypeLiteralConstant constant) { |
| final DartType type = constant.type; |
| final ClassInfo info = translator.classInfo[types.classForType(type)]!; |
| translator.functions.allocateClass(info.classId); |
| if (type is InterfaceType && !types.isSpecializedClass(type.classNode)) { |
| return _makeInterfaceType(constant, type, info); |
| } else if (type is FutureOrType) { |
| return _makeFutureOrType(constant, type, info); |
| } else if (type is FunctionType) { |
| return _makeFunctionType(constant, type, info); |
| } else if (type is ExtensionType) { |
| return ensureConstant(TypeLiteralConstant(type.extensionTypeErasure)); |
| } else if (type is TypeParameterType) { |
| int environmentIndex = |
| types.interfaceTypeEnvironment.lookup(type.parameter); |
| return createConstant(constant, info.nonNullableType, (function, b) { |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.i32_const(types.encodedNullability(type)); |
| b.i64_const(environmentIndex); |
| b.struct_new(info.struct); |
| }); |
| } else if (type is StructuralParameterType) { |
| // The indexing scheme used by function type parameters ensures that |
| // function type parameter types that are identical as constants (have |
| // the same nullability and refer to the same type parameter) have the |
| // same representation and thus can be canonicalized like other |
| // constants. |
| return createConstant(constant, info.nonNullableType, (function, b) { |
| int index = types.getFunctionTypeParameterIndex(type.parameter); |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.i32_const(types.encodedNullability(type)); |
| b.i64_const(index); |
| b.struct_new(info.struct); |
| }); |
| } else if (type is RecordType) { |
| final names = ListConstant( |
| InterfaceType( |
| translator.coreTypes.stringClass, Nullability.nonNullable), |
| type.named.map((t) => StringConstant(t.name)).toList()); |
| ensureConstant(names); |
| final fieldTypes = constants.makeTypeList( |
| type.positional.followedBy(type.named.map((n) => n.type))); |
| ensureConstant(fieldTypes); |
| return createConstant(constant, info.nonNullableType, (function, b) { |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.i32_const(types.encodedNullability(type)); |
| final namesExpectedType = |
| info.struct.fields[FieldIndex.recordTypeNames].type.unpacked; |
| constants.instantiateConstant(function, b, names, namesExpectedType); |
| final typeListExpectedType = |
| info.struct.fields[FieldIndex.recordTypeFieldTypes].type.unpacked; |
| constants.instantiateConstant( |
| function, b, fieldTypes, typeListExpectedType); |
| b.struct_new(info.struct); |
| }); |
| } else if (type is VoidType || |
| type is DynamicType || |
| type is InterfaceType && |
| type.classNode == translator.coreTypes.objectClass) { |
| return createConstant(constant, info.nonNullableType, (function, b) { |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.i32_const(types.encodedNullability(type)); |
| b.i64_const(types.topTypeKind(type)); |
| b.struct_new(info.struct); |
| }); |
| } else { |
| assert(type is NeverType || |
| type is NullType || |
| type is InterfaceType && types.isSpecializedClass(type.classNode)); |
| return createConstant(constant, info.nonNullableType, (function, b) { |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| b.i32_const(types.encodedNullability(type)); |
| b.struct_new(info.struct); |
| }); |
| } |
| } |
| |
| @override |
| ConstantInfo? visitSymbolConstant(SymbolConstant constant) { |
| ClassInfo info = translator.classInfo[translator.symbolClass]!; |
| translator.functions.allocateClass(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, |
| (function, b) { |
| b.i32_const(info.classId); |
| b.i32_const(initialIdentityHash); |
| constants.instantiateConstant(function, b, nameConstant, stringType); |
| b.struct_new(info.struct); |
| }); |
| } |
| |
| @override |
| ConstantInfo? visitRecordConstant(RecordConstant constant) { |
| final ClassInfo recordClassInfo = |
| translator.getRecordClassInfo(constant.recordType); |
| translator.functions.allocateClass(recordClassInfo.classId); |
| |
| final List<Constant> arguments = constant.positional.toList(); |
| arguments.addAll(constant.named.values); |
| |
| for (Constant argument in arguments) { |
| ensureConstant(argument); |
| } |
| |
| return createConstant(constant, recordClassInfo.nonNullableType, |
| lazy: false, (function, b) { |
| b.i32_const(recordClassInfo.classId); |
| b.i32_const(initialIdentityHash); |
| for (Constant argument in arguments) { |
| constants.instantiateConstant( |
| function, b, argument, translator.topInfo.nullableType); |
| } |
| b.struct_new(recordClassInfo.struct); |
| }); |
| } |
| } |
