Merge pull request #12915 from slavapestov/reabstract-bridged-value-4.1

SILGen: Fix bridging of optional function types to AnyObject [4.1]

Author: slavapestov

lib/SILGen/SILGenBridging.cpp

@@ -127,6 +127,16 @@ emitBridgeNativeToObjectiveC(SILGenFunction &SGF,
   // Substitute into the witness function type.
   witnessFnTy = witnessFnTy.substGenericArgs(SGF.SGM.M, typeSubMap);
 
+  // We might have to re-abstract the 'self' value if it is an
+  // Optional.
+  AbstractionPattern origSelfType(witness->getInterfaceType());
+  origSelfType = origSelfType.getFunctionInputType();
+
+  swiftValue = SGF.emitSubstToOrigValue(loc, swiftValue,
+                                        origSelfType,
+                                        swiftValueType,
+                                        SGFContext());
+
   // The witness may be more abstract than the concrete value we're bridging,
   // for instance, if the value is a concrete instantiation of a generic type.
   //

test/SILGen/objc_bridging_any.swift

@@ -736,6 +736,16 @@ class AnyHashableClass : NSObject {
   }
 }
 
+// CHECK-LABEL: sil hidden @_T017objc_bridging_any33bridgeOptionalFunctionToAnyObjectyXlyycSg2fn_tF : $@convention(thin) (@owned Optional<@callee_owned () -> ()>) -> @owned AnyObject
+// CHECK: [[BRIDGE:%.*]] = function_ref @_T0Sq19_bridgeToObjectiveCyXlyF
+// CHECK: [[FN:%.*]] = function_ref @_T0Iex_ytytIexir_TR
+// CHECK: partial_apply [[FN]]
+// CHECK: [[SELF:%.*]] = alloc_stack $Optional<@callee_owned (@in ()) -> @out ()>
+// CHECK: apply [[BRIDGE]]<() -> ()>([[SELF]])
+func bridgeOptionalFunctionToAnyObject(fn: (() -> ())?) -> AnyObject {
+  return fn as AnyObject
+}
+
 // CHECK-LABEL: sil_witness_table shared [serialized] GenericOption: Hashable module objc_generics {
 // CHECK-NEXT: base_protocol Equatable: GenericOption: Equatable module objc_generics
 // CHECK-NEXT: method #Hashable.hashValue!getter.1: {{.*}} : @_T0SC13GenericOptionVs8Hashable13objc_genericssACP9hashValueSivgTW