[SwiftBindings] Added TypeMetadata, removed SwiftTypeInfo #2804
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| @@ -292,7 +293,7 @@ private List<BaseDecl> CollectDeclarations(IEnumerable<Node> nodes, BaseDecl par | |||
| { | |||
| decl = CreateClassDecl(node, parentDecl, moduleDecl); | |||
| } | |||
| typeRecord.SwiftTypeInfo = swiftTypeInfo; | |||
| typeRecord.SwiftTypeInfo = swiftTypeInfo; | |||
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This doesn't look intentional? Unindent by one space?
| /// </summary> | ||
| [Flags] | ||
| public enum TypeMetadataFlags { | ||
| /// <summary> |
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Would it make sense to add a None = 0 value, since this enum represents flags?
| MetadataKindIsNonType = 0x400, | ||
| /// <summary> | ||
| /// The metadata doesn't live on the heap | ||
| /// </summary> | ||
| MetadataKindIsNonHeap = 0x200, | ||
| /// <summary> | ||
| /// The type is private to the runtime | ||
| /// </summary> | ||
| MetadataKindIsRuntimePrivate = 0x100, |
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Is MetadataKind a common prefix for all values, or will there be more flags that aren't MetadataKind flags? If the former, the prefix should be removed:
| MetadataKindIsNonType = 0x400, | |
| /// <summary> | |
| /// The metadata doesn't live on the heap | |
| /// </summary> | |
| MetadataKindIsNonHeap = 0x200, | |
| /// <summary> | |
| /// The type is private to the runtime | |
| /// </summary> | |
| MetadataKindIsRuntimePrivate = 0x100, | |
| IsNonType = 0x400, | |
| /// <summary> | |
| /// The metadata doesn't live on the heap | |
| /// </summary> | |
| IsNonHeap = 0x200, | |
| /// <summary> | |
| /// The type is private to the runtime | |
| /// </summary> | |
| IsRuntimePrivate = 0x100, |
| get { | ||
| ThrowOnInvalid (); | ||
| long val = ReadPointerSizedInt (handle); | ||
| if (val == 0) |
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Looks like there's a mix of spaces and tabs here.
Also you can't load dylibs for other than the current platform (so you won't be able to load dylibs for iOS on macOS for instance). |
| /// <summary> | ||
| /// Represents the type metadata for a Swift type | ||
| /// </summary> | ||
| public readonly struct TypeMetadata : IEquatable<TypeMetadata> { |
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How this correlates with SwiftMetadata? Do we plan to use metadata for type semantics on the C# side or only as an unmanaged pointer for callconv?
This is a very simple implementation of TypeMetadata to get @jkurdek unblocked.
It includes access to the metadata kind and not a lot else for now.
The goal of this is to be used as a runtime type not a compile time type.
For the time being I removed SwiftTypeInfo which uses info pulled directly from the data structures in the dylib. We should discuss this in more detail in terms of how we want to get this information. As background, it's not a great idea to fully load a dylib at compile time since it can execute arbitrary code (see
__attribute__((constructor))) just by being loaded and may have dependencies that we don't know about or may load dependencies that conflict with the binding tool itself.TypeMetadata is designed to be used in any place that a Swift call needs a type metadata object, such as implicit arguments in a generic function or in an existential type. To get one, you should use this as the return type for a Metadata Accessor function or the appropriate Swift runtime call to generate/get them from a cache for tuples, functions etc.
Added issues to address:
#2800
#2801
#2802
#2803