Reflection: Flesh out SwiftRemoteMirror C API

- Add swift_reflection_genericArgumentCountOfTypeRef()
- Flesh out swift_reflection_infoForTypeRef()
- Flesh out swift_reflection_infoForChild()

Author: slavapestov

include/swift/SwiftRemoteMirror/SwiftRemoteMirror.h

@@ -74,6 +74,10 @@ swift_reflection_infoForField(SwiftReflectionContextRef ContextRef,
                               swift_typeref_t OpaqueTypeRef,
                               unsigned Index);
 
+/// Returns a fully instantiated typeref for a generic argument by index.
+unsigned
+swift_reflection_genericArgumentCountOfTypeRef(swift_typeref_t OpaqueTypeRef);
+
 /// Returns a fully instantiated typeref for a generic argument by index.
 swift_typeref_t
 swift_reflection_genericArgumentOfTypeRef(swift_typeref_t OpaqueTypeRef,

include/swift/SwiftRemoteMirror/SwiftRemoteMirrorTypes.h

@@ -40,35 +40,38 @@ typedef struct swift_reflection_section_t {
 
 /// The kind of a Swift type.
 typedef enum swift_layout_kind_t {
-  SWIFT_STRONG_POINTER,
-  SWIFT_WEAK_POINTER,
-  SWIFT_UNOWNED_POINTER,
-  SWIFT_UNMANAGED_POINTER,
-  SWIFT_STRUCT,
+  SWIFT_UNKNOWN,
+
+  SWIFT_BUILTIN,
+
   SWIFT_TUPLE,
+  SWIFT_STRUCT,
   SWIFT_THICK_FUNCTION,
-  SWIFT_THIN_FUNCTION,
-  OBJC_BLOCK,
-  SWIFT_CLOSURE_CONTEXT,
-  SWIFT_BOX,
-  SWIFT_UNKNOWN
+
+  SWIFT_STRONG_REFERENCE,
+  SWIFT_UNOWNED_REFERENCE,
+  SWIFT_WEAK_REFERENCE,
+  SWIFT_UNMANAGED_REFERENCE,
 } swift_layout_kind_t;
 
-/// A basic description of a Swift type's.
-typedef struct swift_typeinfo_t {
+struct swift_childinfo;
+
+/// A description of the memory layout of a type or field of a type.
+typedef struct swift_typeinfo {
   swift_layout_kind_t LayoutKind;
 
-  const char *MangledTypeName;
+  unsigned Size;
+  unsigned Alignment;
+  unsigned Stride;
 
-  size_t Size;
-  size_t InstanceSize;
-  size_t Alignment;
+  unsigned NumFields;
 } swift_typeinfo_t;
 
-typedef struct swift_childinfo_t {
-  swift_typeref_t TypeRef;
+typedef struct swift_childinfo {
+  /// The memory for Name is owned by the reflection context.
   const char *Name;
-  size_t Offset;
+  unsigned Offset;
+  swift_typeref_t TR;
 } swift_childinfo_t;
 
 /// \brief An opaque pointer to a context which maintains state and

stdlib/public/SwiftRemoteMirror/SwiftRemoteMirror.cpp

@@ -82,9 +82,19 @@ swift_reflection_genericArgumentOfTypeRef(swift_typeref_t OpaqueTypeRef,
 
   if (auto BG = dyn_cast<BoundGenericTypeRef>(TR)) {
     auto &Params = BG->getGenericParams();
-    if (Index < Params.size()) {
-      return reinterpret_cast<swift_typeref_t>(Params[Index]);
-    }
+    assert(Index < Params.size());
+    return reinterpret_cast<swift_typeref_t>(Params[Index]);
+  }
+  return 0;
+}
+
+unsigned
+swift_reflection_genericArgumentCountOfTypeRef(swift_typeref_t OpaqueTypeRef) {
+  auto TR = reinterpret_cast<const TypeRef *>(OpaqueTypeRef);
+
+  if (auto BG = dyn_cast<BoundGenericTypeRef>(TR)) {
+    auto &Params = BG->getGenericParams();
+    return Params.size();
   }
   return 0;
 }
@@ -96,15 +106,64 @@ swift_reflection_infoForTypeRef(SwiftReflectionContextRef ContextRef,
   auto TR = reinterpret_cast<const TypeRef *>(OpaqueTypeRef);
   auto TI = Context->getTypeInfo(TR);
 
-  // TODO
-  (void) TI;
+  if (TI == nullptr) {
+    return {
+      SWIFT_UNKNOWN,
+      0,
+      0,
+      0,
+      0
+    };
+  }
+
+  swift_layout_kind_t Kind;
+  unsigned NumFields = 0;
+
+  switch (TI->getKind()) {
+  case TypeInfoKind::Builtin:
+    Kind = SWIFT_BUILTIN;
+    break;
+  case TypeInfoKind::Record: {
+    auto *RecordTI = cast<RecordTypeInfo>(TI);
+    switch (RecordTI->getRecordKind()) {
+    case RecordKind::Tuple:
+      Kind = SWIFT_TUPLE;
+      break;
+    case RecordKind::Struct:
+      Kind = SWIFT_STRUCT;
+      break;
+    case RecordKind::ThickFunction:
+      Kind = SWIFT_THICK_FUNCTION;
+      break;
+    }
+    NumFields = RecordTI->getNumFields();
+    break;
+  }
+  case TypeInfoKind::Reference: {
+    auto *ReferenceTI = cast<ReferenceTypeInfo>(TI);
+    switch (ReferenceTI->getReferenceKind()) {
+    case ReferenceKind::Strong:
+      Kind = SWIFT_STRONG_REFERENCE;
+      break;
+    case ReferenceKind::Unowned:
+      Kind = SWIFT_UNOWNED_REFERENCE;
+      break;
+    case ReferenceKind::Weak:
+      Kind = SWIFT_WEAK_REFERENCE;
+      break;
+    case ReferenceKind::Unmanaged:
+      Kind = SWIFT_UNMANAGED_REFERENCE;
+      break;
+    }
+  }
+  }
 
   return {
-    SWIFT_UNKNOWN,
-    NULL,
-    0,
-    0,
-    0
+    Kind,
+    TI->getSize(),
+    TI->getAlignment(),
+    TI->getStride(),
+    NumFields
   };
 }
 
@@ -114,15 +173,13 @@ swift_reflection_infoForChild(SwiftReflectionContextRef ContextRef,
                               unsigned Index) {
   auto Context = reinterpret_cast<NativeReflectionContext *>(ContextRef);
   auto TR = reinterpret_cast<const TypeRef *>(OpaqueTypeRef);
-  auto TI = Context->getTypeInfo(TR);
 
-  // TODO
-  (void) TI;
+  auto *RecordTI = cast<RecordTypeInfo>(Context->getTypeInfo(TR));
+  auto FieldInfo = RecordTI->getFields()[Index];
 
   return {
-    0,
-    NULL,
-    0,
+    FieldInfo.Name.c_str(),
+    FieldInfo.Offset,
+    reinterpret_cast<swift_typeref_t>(FieldInfo.TR),
   };
 }
-