Sema: Allow parameterized existential compositions

lib/Sema/TypeCheckType.cpp

@@ -6002,11 +6002,7 @@ TypeResolver::resolveCompositionType(CompositionTypeRepr *repr,
       continue;
     }
 
-    // FIXME: Support compositions involving parameterized protocol types,
-    // like 'any Collection<String> & Sendable', etc.
-    if (ty->is<ParameterizedProtocolType>() &&
-        !options.isConstraintImplicitExistential() &&
-        options.getContext() != TypeResolverContext::ExistentialConstraint) {
+    if (ty->is<ParameterizedProtocolType>()) {
       checkMember(tyR->getStartLoc(), ty);
       Members.push_back(ty);
       continue;

test/Constraints/parameterized_existential_composition.swift

@@ -0,0 +1,61 @@
+// RUN: %target-typecheck-verify-swift -disable-availability-checking
+
+func f1(_ s: any Sequence<Int> & Hashable) -> any Sequence<Int> {
+  return s
+}
+
+func f2(_ s: any Sequence<Int> & Hashable) -> any Hashable {
+  return s
+}
+
+func f3(_ s: any Sequence<Int> & Hashable) -> any Sequence {
+  return s
+}
+
+func f4(_ s: any Sequence<Int> & Hashable) -> any Sequence & Hashable {
+  return s
+}
+
+func f5(_ s: any Sequence<Int> & Hashable) -> any Sequence<Int> & Equatable {
+  return s
+}
+
+func f6(_ s: any Sequence<Int> & Hashable) -> any Sequence<String> & Hashable {
+  return s // expected-error {{cannot convert return expression of type 'Int' to return type 'String'}}
+}
+
+func f7(_ s: any Sequence<Int> & Hashable) -> any Sequence<String> {
+  return s // expected-error {{cannot convert return expression of type 'Int' to return type 'String'}}
+}
+
+func f8(_ s: any Collection<Int> & Hashable) -> any Sequence<Int> & Hashable {
+  return s
+}
+
+// https://github.com/swiftlang/swift/issues/71012
+
+protocol A<T> {
+  associatedtype T
+}
+protocol B {}
+typealias C = A & B
+typealias D<T> = A<T> & B
+
+struct Foo: C {
+  typealias T = Int
+}
+
+struct Bar<Value> { // expected-note {{arguments to generic parameter 'Value' ('any C' (aka 'any A & B') and 'any A<Int> & B') are expected to be equal}}
+  let value: Value
+}
+
+struct Baz<U> {
+  let bar: Bar<any D<U>>
+}
+
+func run() {
+  let foo: any C = Foo()
+  let bar = Bar(value: foo)
+  _ = Baz<Int>(bar: bar)
+  // expected-error@-1 {{cannot convert value of type 'Bar<any C>' (aka 'Bar<any A & B>') to expected argument type 'Bar<any A<Int> & B>'}}
+}

test/SILGen/parameterized_existential_composition.swift

@@ -0,0 +1,40 @@
+// RUN: %target-swift-emit-silgen -disable-availability-checking %s | %FileCheck %s
+
+protocol P<A> {
+  associatedtype A
+}
+
+protocol Q<B> {
+  associatedtype B
+}
+
+// All of these should have unique mangling.
+func overload(_: any P<Int> & Q<String>) {}
+func overload(_: any P<Float> & Q<String>) {}
+func overload(_: any P & Q<String>) {}
+func overload(_: any P<Int> & Q<Bool>) {}
+func overload(_: any P<Float> & Q<Bool>) {}
+func overload(_: any P & Q<Bool>) {}
+func overload(_: any P<Int> & Q) {}
+func overload(_: any P<Float> & Q) {}
+func overload(_: any P & Q) {}
+func overload(_: any P<Int>) {}
+func overload(_: any P<Float>) {}
+func overload(_: any P) {}
+func overload(_: any Q<Bool>) {}
+func overload(_: any Q) {}
+
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_AA1QpSi1AAaCPRts_SS1BAaDPRtsXPF : $@convention(thin) (@in_guaranteed any P<Int> & Q<String>) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_AA1QpSf1AAaCPRts_SS1BAaDPRtsXPF : $@convention(thin) (@in_guaranteed any P<Float> & Q<String>) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_AA1QpSS1BAaDPRts_XPF : $@convention(thin) (@in_guaranteed any P & Q<String>) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_AA1QpSi1AAaCPRts_Sb1BAaDPRtsXPF : $@convention(thin) (@in_guaranteed any P<Int> & Q<Bool>) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_AA1QpSf1AAaCPRts_Sb1BAaDPRtsXPF : $@convention(thin) (@in_guaranteed any P<Float> & Q<Bool>) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_AA1QpSb1BAaDPRts_XPF : $@convention(thin) (@in_guaranteed any P & Q<Bool>) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_AA1QpSi1AAaCPRts_XPF : $@convention(thin) (@in_guaranteed any P<Int> & Q) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_AA1QpSf1AAaCPRts_XPF : $@convention(thin) (@in_guaranteed any P<Float> & Q) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_AA1QpF : $@convention(thin) (@in_guaranteed any P & Q) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_pSi1AAaCPRts_XPF : $@convention(thin) (@in_guaranteed any P<Int>) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_pSf1AAaCPRts_XPF : $@convention(thin) (@in_guaranteed any P<Float>) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1P_pF : $@convention(thin) (@in_guaranteed any P) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1Q_pSb1BAaCPRts_XPF : $@convention(thin) (@in_guaranteed any Q<Bool>) -> () {
+// CHECK-LABEL: sil hidden [ossa] @$s37parameterized_existential_composition8overloadyyAA1Q_pF : $@convention(thin) (@in_guaranteed any Q) -> () {

test/decl/protocol/existential_member_access/basic.swift

@@ -506,8 +506,6 @@ do {
     func invariant11() -> Struct<${type}>.InnerGeneric<Void>
     // https://github.com/apple/swift/issues/61934
     func invariant12() -> any Sequence<${type}>
-    // FIXME
-    // expected-error@+1 {{non-protocol, non-class type 'Sequence<${type}>' cannot be used within a protocol-constrained type}}
     func invariant13() -> any P & Sequence<${type}>
     func invariant14() -> (any Sequence<${type}>).Type
     func invariant15() -> any (P & Class<${type}>).Type

test/type/parameterized_existential.swift

@@ -82,16 +82,6 @@ func typeExpr() {
   _ = (any Sequence<Int>).self
 }
 
-/// Not supported as a protocol composition term for now
-
-protocol SomeProto {}
-
-func protocolCompositionNotSupported1(_: SomeProto & Sequence<Int>) {}
-// expected-error@-1 {{non-protocol, non-class type 'Sequence<Int>' cannot be used within a protocol-constrained type}}
-
-func protocolCompositionNotSupported2(_: any SomeProto & Sequence<Int>) {}
-// expected-error@-1 {{non-protocol, non-class type 'Sequence<Int>' cannot be used within a protocol-constrained type}}
-
 func increment(_ n : any Collection<Float>) {
   for value in n {
       _ = value + 1