[ABI] Introduce MetadataKind TypeRef

Author: Azoy

include/swift/ABI/Metadata.h

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -2325,6 +2325,7 @@ struct TargetTypeMetadataRecord {
     // in the future) are just never used in these lists.
     case TypeReferenceKind::DirectObjCClassName:
     case TypeReferenceKind::IndirectObjCClass:
+    case TypeReferenceKind::MetadataKind:
       return nullptr;
     }
 
@@ -2415,6 +2416,9 @@ struct TargetTypeReference {
     /// A direct reference to an Objective-C class name.
     RelativeDirectPointer<const char>
       DirectObjCClassName;
+
+    /// A "reference" to some metadata kind, e.g. tuple.
+    MetadataKind MetadataKind;
   };
 
   const TargetContextDescriptor<Runtime> *
@@ -2428,12 +2432,18 @@ struct TargetTypeReference {
 
     case TypeReferenceKind::DirectObjCClassName:
     case TypeReferenceKind::IndirectObjCClass:
+    case TypeReferenceKind::MetadataKind:
       return nullptr;
     }
 
     return nullptr;
   }
 
+  enum MetadataKind getMetadataKind(TypeReferenceKind kind) const {
+    assert(kind == TypeReferenceKind::MetadataKind);
+    return MetadataKind;
+  }
+
 #if SWIFT_OBJC_INTEROP
   /// If this type reference is one of the kinds that supports ObjC
   /// references,
@@ -2519,6 +2529,10 @@ struct TargetProtocolConformanceDescriptor final
     return Flags.getTypeReferenceKind();
   }
 
+  enum MetadataKind getMetadataKind() const {
+    return TypeRef.getMetadataKind(getTypeKind());
+  }
+
   const char *getDirectObjCClassName() const {
     return TypeRef.getDirectObjCClassName(getTypeKind());
   }
@@ -2546,6 +2560,11 @@ struct TargetProtocolConformanceDescriptor final
         TargetRelativeContextPointer<Runtime>>();
   }
 
+  /// Whether this conformance is builtin by the compiler + runtime.
+  bool isBuiltin() const {
+    return getTypeKind() == TypeReferenceKind::MetadataKind;
+  }
+
   /// Whether this conformance is non-unique because it has been synthesized
   /// for a foreign type.
   bool isSynthesizedNonUnique() const {

include/swift/ABI/MetadataValues.h

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -384,10 +384,14 @@ enum class TypeReferenceKind : unsigned {
   /// unused.
   IndirectObjCClass = 0x03,
 
+  /// The conformance is for a non-nominal type whose metadata kind we recorded;
+  /// getMetadataKind() returns the kind.
+  MetadataKind = 0x04,
+
   // We only reserve three bits for this in the various places we store it.
 
   First_Kind = DirectTypeDescriptor,
-  Last_Kind = IndirectObjCClass,
+  Last_Kind = MetadataKind,
 };
 
 /// Flag that indicates whether an existential type is class-constrained or not.

include/swift/Remote/MetadataReader.h

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -1414,6 +1414,9 @@ class MetadataReader {
 
       return metadataFn(metadata);
     }
+    case TypeReferenceKind::MetadataKind: {
+      return None;
+    }
     }
 
     return None;

stdlib/public/runtime/Metadata.cpp

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -193,6 +193,9 @@ computeMetadataBoundsForSuperclass(const void *ref,
     break;
 #endif
   }
+  // Type metadata type ref is unsupported here.
+  case TypeReferenceKind::MetadataKind:
+    break;
   }
   swift_unreachable("unsupported superclass reference kind");
 }

stdlib/public/runtime/ProtocolConformance.cpp

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -83,11 +83,14 @@ template<> void ProtocolConformanceDescriptor::dump() const {
   case TypeReferenceKind::IndirectTypeDescriptor:
     printf("unique nominal type descriptor %s", symbolName(getTypeDescriptor()));
     break;
+  case TypeReferenceKind::MetadataKind:
+    printf("metadata kind %i", getMetadataKind());
+    break;
   }
 
   printf(" => ");
 
-  printf("witness table %pattern s\n", symbolName(getWitnessTablePattern()));
+  printf("witness table pattern %p\n", symbolName(getWitnessTablePattern()));
 }
 #endif
 
@@ -113,6 +116,7 @@ const ClassMetadata *TypeReference::getObjCClass(TypeReferenceKind kind) const {
 
   case TypeReferenceKind::DirectTypeDescriptor:
   case TypeReferenceKind::IndirectTypeDescriptor:
+  case TypeReferenceKind::MetadataKind:
     return nullptr;
   }
 
@@ -153,6 +157,9 @@ ProtocolConformanceDescriptor::getCanonicalTypeMetadata() const {
 
     return nullptr;
   }
+  case TypeReferenceKind::MetadataKind: {
+    return nullptr;
+  }
   }
 
   swift_unreachable("Unhandled TypeReferenceKind in switch.");

stdlib/toolchain/Compatibility51/ProtocolConformance.cpp

@@ -229,6 +229,9 @@ override_getCanonicalTypeMetadata(const ProtocolConformanceDescriptor *conf) {
 
     return nullptr;
   }
+  case TypeReferenceKind::MetadataKind: {
+    return nullptr;
+  }
   }
 
   swift_unreachable("Unhandled TypeReferenceKind in switch.");