| // Copyright (c) 2013, 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. |
| |
| part of types; |
| |
| /// A holder for an element type. We define a special class for it so |
| /// that nullable ContainerTypeMask and non-nullable ContainerTypeMask |
| /// share the same [ElementTypeHolder]. |
| class ElementTypeHolder { |
| // These fields will be set after global analysis. |
| TypeMask elementType; |
| int length; |
| |
| int get hashCode => elementType.hashCode; |
| } |
| |
| /// A [ContainerTypeMask] is a [TypeMask] for a specific allocation |
| /// site of a container (currently only List) that will get specialized |
| /// once the [ListTracer] phase finds an element type for it. |
| class ContainerTypeMask extends ForwardingTypeMask { |
| // The flat version of a [ContainerTypeMask] is the container type |
| // (for example List). |
| final FlatTypeMask forwardTo; |
| |
| // The [Node] where this type mask was created. |
| final Node allocationNode; |
| |
| // The [Element] where this type mask was created. |
| final Element allocationElement; |
| |
| // A holder for the element type. Shared between all |
| // [ContainerTypeMask] for the same node. |
| final ElementTypeHolder holder; |
| |
| TypeMask get elementType => holder.elementType; |
| void set elementType(TypeMask mask) { |
| holder.elementType = mask; |
| } |
| int get length => holder.length; |
| void set length(int length) { |
| holder.length = length; |
| } |
| |
| ContainerTypeMask(this.forwardTo, |
| this.allocationNode, |
| this.allocationElement, |
| [holder]) |
| : this.holder = (holder == null) ? new ElementTypeHolder() : holder; |
| |
| TypeMask nullable() { |
| return isNullable |
| ? this |
| : new ContainerTypeMask(forwardTo.nullable(), |
| allocationNode, |
| allocationElement, |
| holder); |
| } |
| |
| TypeMask nonNullable() { |
| return isNullable |
| ? new ContainerTypeMask(forwardTo.nonNullable(), |
| allocationNode, |
| allocationElement, |
| holder) |
| : this; |
| } |
| |
| bool get isContainer => true; |
| bool get isExact => true; |
| |
| bool equalsDisregardNull(other) { |
| if (other is! ContainerTypeMask) return false; |
| return allocationNode == other.allocationNode; |
| } |
| |
| TypeMask intersection(TypeMask other, Compiler compiler) { |
| TypeMask forwardIntersection = forwardTo.intersection(other, compiler); |
| if (forwardIntersection.isEmpty) return forwardIntersection; |
| return forwardIntersection.isNullable |
| ? nullable() |
| : nonNullable(); |
| } |
| |
| bool operator==(other) { |
| if (other is! ContainerTypeMask) return false; |
| return allocationNode == other.allocationNode |
| && isNullable == other.isNullable; |
| } |
| |
| int get hashCode => computeHashCode(allocationNode, isNullable); |
| |
| String toString() { |
| return 'Container mask: $elementType'; |
| } |
| } |