[TypeLowering] Return pseudogeneric @autoreleasing

Previously, when a pseudogeneric function returned a type parameter, it
was unowned.  That resulted in invalid OSSA out of SILGen.  Here, this
is fixed to use the @autoreleasing convention.

rdar://64375208

Author: nate-chandler

lib/SIL/IR/SILFunctionType.cpp

@@ -3797,10 +3797,12 @@ namespace {
 
 class ObjCSelectorFamilyConventions : public Conventions {
   ObjCSelectorFamily Family;
+  bool pseudogeneric;
 
 public:
-  ObjCSelectorFamilyConventions(ObjCSelectorFamily family)
-    : Conventions(ConventionsKind::ObjCSelectorFamily), Family(family) {}
+  ObjCSelectorFamilyConventions(ObjCSelectorFamily family, bool pseudogeneric)
+      : Conventions(ConventionsKind::ObjCSelectorFamily), Family(family),
+        pseudogeneric(pseudogeneric) {}
 
   ParameterConvention getIndirectParameter(unsigned index,
                                            const AbstractionPattern &type,
@@ -3840,8 +3842,9 @@ class ObjCSelectorFamilyConventions : public Conventions {
     // Get the underlying AST type, potentially stripping off one level of
     // optionality while we do it.
     CanType type = tl.getLoweredType().unwrapOptionalType().getASTType();
-    if (type->hasRetainablePointerRepresentation()
-        || (type->getSwiftNewtypeUnderlyingType() && !tl.isTrivial()))
+    if (type->hasRetainablePointerRepresentation() ||
+        (type->getSwiftNewtypeUnderlyingType() && !tl.isTrivial()) ||
+        (isa<GenericTypeParamType>(type) && pseudogeneric))
       return ResultConvention::Autoreleased;
 
     return ResultConvention::Unowned;
@@ -3871,10 +3874,14 @@ static CanSILFunctionType getSILFunctionTypeForObjCSelectorFamily(
     TypeConverter &TC, ObjCSelectorFamily family, CanAnyFunctionType origType,
     CanAnyFunctionType substInterfaceType, SILExtInfoBuilder extInfoBuilder,
     const ForeignInfo &foreignInfo, std::optional<SILDeclRef> constant) {
+  CanGenericSignature genericSig = substInterfaceType.getOptGenericSignature();
+  bool pseudogeneric =
+      genericSig && constant ? isPseudogeneric(*constant) : false;
   return getSILFunctionType(
       TC, TypeExpansionContext::minimal(), AbstractionPattern(origType),
-      substInterfaceType, extInfoBuilder, ObjCSelectorFamilyConventions(family),
-      foreignInfo, constant, constant,
+      substInterfaceType, extInfoBuilder,
+      ObjCSelectorFamilyConventions(family, pseudogeneric), foreignInfo,
+      constant, constant,
       /*requirement subs*/ std::nullopt, ProtocolConformanceRef());
 }
 

test/PrintAsObjC/extensions.swift

@@ -1,19 +1,12 @@
 // Please keep this file in alphabetical order!
 
 // RUN: %empty-directory(%t)
-// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -disable-sil-ownership-verifier -emit-module -o %t %s -disable-objc-attr-requires-foundation-module -Xllvm -sil-disable-pass=MandatoryARCOpts
-// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -disable-sil-ownership-verifier -parse-as-library %t/extensions.swiftmodule -typecheck -emit-objc-header-path %t/extensions.h -import-objc-header %S/../Inputs/empty.h -disable-objc-attr-requires-foundation-module -Xllvm -sil-disable-pass=MandatoryARCOpts
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -emit-module -o %t %s -disable-objc-attr-requires-foundation-module -Xllvm -sil-disable-pass=MandatoryARCOpts
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -parse-as-library %t/extensions.swiftmodule -typecheck -emit-objc-header-path %t/extensions.h -import-objc-header %S/../Inputs/empty.h -disable-objc-attr-requires-foundation-module -Xllvm -sil-disable-pass=MandatoryARCOpts
 // RUN: %FileCheck %s --input-file %t/extensions.h
 // RUN: %FileCheck --check-prefix=NEGATIVE %s --input-file %t/extensions.h
 // RUN: %check-in-clang %t/extensions.h
 
-// This test generates invalid SIL. It will cause a compiler assert in
-// both -Onone and -O builds:
-// Error! Found a leaked owned value that was never consumed.
-// -disable-sil-ownership-verifier is a temporary workaround.
-// rdar://64375208 (Wrong lowering of PrintAsObjC code. Result is
-// unowned instead of autoreleased)
-
 // REQUIRES: objc_interop
 
 import Foundation

test/SILGen/Inputs/usr/include/objc_extensions_helper.h

@@ -4,3 +4,9 @@
 - (void)objCBaseMethod;
 @property (nonatomic, strong) NSString *prop;
 @end
+
+@protocol Pettable
+@end
+
+@interface PettableContainer<T : id<Pettable>> : NSObject
+@end

test/SILGen/objc_extensions.swift

@@ -185,3 +185,10 @@ func testStaticVarAccess() {
   // CHECK: [[ADDR:%.*]] = pointer_to_address [[PTR]]
   _ = Base.x
 }
+
+extension PettableContainer {
+  // CHECK-LABEL: sil private [thunk] [ossa] @$sSo17PettableContainerC15objc_extensionsE7extractxyFTo : $@convention(objc_method) @pseudogeneric <T where T : Pettable> (PettableContainer<T>) -> @autoreleased T
+  @objc public func extract() -> T { fatalError() }
+// CHECK-LABEL: sil private [thunk] [ossa] @$sSo17PettableContainerC15objc_extensionsE8extract2xSgyFTo : $@convention(objc_method) @pseudogeneric <T where T : Pettable> (PettableContainer<T>) -> @autoreleased Optional<T>
+  @objc public func extract2() -> T? { fatalError() }
+}