Reflection: Emit descriptors for referenced imported protocols

When we encounter a protocol typeref, we have to know if its @objc,
class-bound, or opaque, so make sure we provide the necessary
information when imported protocols are referenced.

Author: slavapestov

lib/IRGen/GenReflection.cpp

@@ -188,11 +188,13 @@ class ReflectionMetadataBuilder : public ConstantBuilder<> {
       // for now, at least until we want to import C++ types or
       // something like that.
       //
-      // Classes go down a different path.
+      // Classes and protocols go down a different path.
       if (auto Nominal = t->getAnyNominal())
         if (Nominal->hasClangNode()) {
           if (auto CD = dyn_cast<ClassDecl>(Nominal))
             IGM.ImportedClasses.insert(CD);
+          else if (auto PD = dyn_cast<ProtocolDecl>(Nominal))
+            IGM.ImportedProtocols.insert(PD);
           else
             IGM.BuiltinTypes.insert(CanType(t));
         }
@@ -372,7 +374,9 @@ class FieldTypeMetadataBuilder : public ReflectionMetadataBuilder {
     auto type = NTD->getDeclaredType()->getCanonicalType();
     addTypeRef(NTD->getModuleContext(), type);
 
-    if (NTD->hasClangNode() && !isa<ClassDecl>(NTD))
+    if (NTD->hasClangNode() &&
+        !isa<ClassDecl>(NTD) &&
+        !isa<ProtocolDecl>(NTD))
       return;
 
     switch (NTD->getKind()) {
@@ -884,6 +888,9 @@ void IRGenModule::emitBuiltinReflectionMetadata() {
   for (auto CD : ImportedClasses)
     emitFieldMetadataRecord(CD);
 
+  for (auto PD : ImportedProtocols)
+    emitFieldMetadataRecord(PD);
+
   BuiltinTypeMetadataBuilder builder(*this);
   auto var = builder.emit();
   if (var)

lib/IRGen/IRGenModule.h

@@ -721,6 +721,9 @@ class IRGenModule {
   /// Imported classes referenced by types in this module when emitting
   /// reflection metadata.
   llvm::SetVector<ClassDecl *> ImportedClasses;
+  /// Imported protocols referenced by types in this module when emitting
+  /// reflection metadata.
+  llvm::SetVector<ProtocolDecl *> ImportedProtocols;
 
   llvm::Constant *getAddrOfStringForTypeRef(StringRef Str);
   llvm::Constant *getAddrOfFieldName(StringRef Name);

test/Reflection/Inputs/ObjectiveCTypes.swift

@@ -29,6 +29,6 @@ public class HasObjCClasses {
   let rect = NSRect(x: 0, y: 1, width: 2, height: 3)
 }
 
-public func closureHasObjCClasses(b: NSBundle) -> () -> () {
-  return { _ = b }
+public func closureHasObjCClasses(b: NSBundle, c: NSCoding) -> () -> () {
+  return { _ = b; _ = c }
 }

test/Reflection/typeref_decoding_objc.swift

@@ -45,6 +45,8 @@
 // CHECK: ---------------
 // CHECK: __ObjC.NSURL
 // CHECK: ------------
+// CHECK: __ObjC.NSCoding
+// CHECK: ---------------
 
 // CHECK: ASSOCIATED TYPES:
 // CHECK: =================
@@ -72,6 +74,23 @@
 // CHECK:   (tuple))
 // CHECK: - Metadata sources:
 
+// CHECK: - Capture types:
+// CHECK: (struct Swift.StaticString)
+// CHECK: (struct Swift.StaticString)
+// CHECK: (struct Swift.UInt)
+// CHECK: (struct Swift.UInt)
+// CHECK: - Metadata sources:
+
+// CHECK: - Capture types:
+// CHECK: (function
+// CHECK:   (tuple))
+// CHECK: - Metadata sources:
+
+// CHECK: - Capture types:
+// CHECK: (class __ObjC.NSBundle)
+// CHECK: (protocol __ObjC.NSCoding)
+// CHECK: - Metadata sources:
+
 // CHECK: - Capture types:
 // CHECK: (struct Swift.StaticString)
 // CHECK: (bound_generic_struct Swift.UnsafeBufferPointer

validation-test/Reflection/functions_objc.swift

@@ -6,38 +6,42 @@
 import SwiftReflectionTest
 import Foundation
 
-func capturesImportedClass(x: Int, n: NSURL, r: NSRect) {
-  reflect(function: {print(x); print(n); print(r)})
+func capturesImportedTypes(x: Int, n: NSURL, r: NSRect, c: NSCoding) {
+  reflect(function: {print(x); print(n); print(r); print(c)})
 
 // CHECK-32:      Type reference:
 // CHECK-32-NEXT: (builtin Builtin.NativeObject)
 
 // CHECK-32:      Type info:
-// CHECK-32-NEXT: (closure_context size=56 alignment=8 stride=56 num_extra_inhabitants=0
+// CHECK-32-NEXT: (closure_context size=60 alignment=8 stride=60 num_extra_inhabitants=0
 // CHECK-32-NEXT:   (field offset=12
 // CHECK-32-NEXT:     (struct size=4 alignment=4 stride=4 num_extra_inhabitants=0
 // CHECK-32-NEXT:       (field name=_value offset=0
 // CHECK-32-NEXT:         (builtin size=4 alignment=4 stride=4 num_extra_inhabitants=0))))
 // CHECK-32-NEXT:   (field offset=16
 // CHECK-32-NEXT:     (reference kind=strong refcounting=unknown))
 // CHECK-32-NEXT:   (field offset=24
-// CHECK-32-NEXT:     (builtin size=32 alignment=8 stride=32 num_extra_inhabitants=0)))
+// CHECK-32-NEXT:     (builtin size=32 alignment=8 stride=32 num_extra_inhabitants=0))
+// CHECK-32-NEXT:   (field offset=56
+// CHECK-32-NEXT:     (reference kind=strong refcounting=unknown)))
 
 // CHECK-64:      Type reference:
 // CHECK-64-NEXT: (builtin Builtin.NativeObject)
 
 // CHECK-64:      Type info:
-// CHECK-64-NEXT: (closure_context size=64 alignment=8 stride=64 num_extra_inhabitants=0
+// CHECK-64-NEXT: (closure_context size=72 alignment=8 stride=72 num_extra_inhabitants=0
 // CHECK-64-NEXT:   (field offset=16
 // CHECK-64-NEXT:     (struct size=8 alignment=8 stride=8 num_extra_inhabitants=0
 // CHECK-64-NEXT:       (field name=_value offset=0
 // CHECK-64-NEXT:         (builtin size=8 alignment=8 stride=8 num_extra_inhabitants=0))))
 // CHECK-64-NEXT:   (field offset=24
 // CHECK-64-NEXT:     (reference kind=strong refcounting=unknown))
 // CHECK-64-NEXT:   (field offset=32
-// CHECK-64-NEXT:     (builtin size=32 alignment=8 stride=32 num_extra_inhabitants=0)))
+// CHECK-64-NEXT:     (builtin size=32 alignment=8 stride=32 num_extra_inhabitants=0))
+// CHECK-64-NEXT:   (field offset=64
+// CHECK-64-NEXT:     (reference kind=strong refcounting=unknown)))
 }
 
-capturesImportedClass(x: 10, n: NSURL(), r: NSRect(x: 1, y: 2, width: 3, height: 4))
+capturesImportedTypes(x: 10, n: NSURL(), r: NSRect(x: 1, y: 2, width: 3, height: 4), c: "" as NSString)
 
 doneReflecting()