Sema: Simplify opened existential types in solution

Author: slavapestov

lib/Sema/CSSolver.cpp

@@ -169,7 +169,10 @@ Solution ConstraintSystem::finalize() {
   }
 
   // Remember the opened existential types.
-  for (const auto &openedExistential : OpenedExistentialTypes) {
+  for (auto &openedExistential : OpenedExistentialTypes) {
+    openedExistential.second = simplifyType(openedExistential.second)
+        ->castTo<OpenedArchetypeType>();
+
     assert(solution.OpenedExistentialTypes.count(openedExistential.first) == 0||
            solution.OpenedExistentialTypes[openedExistential.first]
              == openedExistential.second &&

test/Constraints/issue-64621.swift

@@ -0,0 +1,13 @@
+// RUN: %target-typecheck-verify-swift
+
+protocol Wrapper<T> {
+  associatedtype T
+
+  func get()
+}
+
+func foo<R>(_: R) -> any Wrapper<R> {}
+
+func test() {
+  foo(0).get()
+}

test/Constraints/rdar120791071.swift

@@ -0,0 +1,14 @@
+// RUN: %target-typecheck-verify-swift
+
+struct S<A> {
+  let v:any P<A>
+  func map<B> (_ f:(A) -> B) -> S<B> {
+    v.map(f).k()
+  }
+}
+
+protocol P<A> {
+  associatedtype A
+  func map<D> (_ g:(A) -> D) -> any P<D>
+  func k() -> S<A>
+}

validation-test/compiler_crashers_2_fixed/issue-74721-2.swift

@@ -0,0 +1,76 @@
+// RUN: %target-swift-frontend -emit-ir %s
+
+protocol Context: Sendable {}
+
+protocol Service<ServiceContext> {
+    associatedtype ServiceContext: Context
+}
+
+protocol Builder<BuilderContext> {
+    associatedtype BuilderContext: Context
+
+    init(context: BuilderContext?)
+
+    func withContextReducer(
+        reducer: @escaping @Sendable (_ context: BuilderContext?) async -> BuilderContext?
+    ) -> Self
+
+
+    func build() -> Result<any Service<BuilderContext>, Error>
+}
+
+final actor ServiceImplementation<ServiceContext: Context>: Service {
+    var currentContext: ServiceContext?
+
+    init(initialContext: ServiceContext?) {
+        currentContext = initialContext
+    }
+}
+
+final class BuilderImplementation<BuilderContext: Context>: Builder {
+    var initialContext: BuilderContext? = nil
+
+    init(context: BuilderContext?) {
+        initialContext = context
+    }
+
+    func withContextReducer(
+        reducer: @escaping @Sendable (_ context: BuilderContext?) async -> BuilderContext?
+    ) -> Self {
+        return self
+    }
+
+    func build() -> Result<any Service<BuilderContext>, Error> {
+        return .success(
+            ServiceImplementation(
+                initialContext: initialContext
+            )
+        )
+    }
+}
+
+enum BuilderFactory {
+    // The generic parameter here makes the swift compiler crash
+    static func create<T: Context>(context: T?) -> any Builder<T> {
+        return BuilderImplementation(context: context)
+    }
+}
+
+
+struct DemoContext: Context {
+    let someValue: Int?
+
+    public init(someValue: Int? = nil) {
+        self.someValue = someValue
+    }
+}
+
+public func testBuilding() {
+        let builderResult: Result<any Service<DemoContext>, Error> = BuilderFactory.create(context: DemoContext())
+            .withContextReducer(
+                reducer: { (context: DemoContext?) -> DemoContext? in context }
+            )
+            .build()
+    }
+
+testBuilding()

validation-test/compiler_crashers_2_fixed/rdar106820674.swift

@@ -0,0 +1,40 @@
+// RUN: %target-swift-frontend -emit-ir %s
+
+public protocol P1 {}
+
+public protocol P2 {
+    associatedtype A1
+    var id: String { get }
+}
+
+public protocol P3<A2> {
+    associatedtype A2
+    func execute()  -> A2
+}
+
+public protocol P4<A3>: P3 {
+    associatedtype A3: P1
+}
+
+public protocol P5<A3>: P4 {}
+
+public protocol P6 {
+    func insert<A3: P1>(id: String, _ value: A3, replace: Bool) -> any P5<A3>
+    func remove<A4: P2>(with key: A4) where A4.A1: P1
+}
+
+extension P6 {
+    public func persist<A4: P2>(_ value: A4.A1?, for key: A4) where A4.A1: P1 {
+        guard let value else {
+            self.remove(with: key)
+            return
+        }
+
+        _ = self.insert(id: key.id, value).execute()
+    }
+    
+    public func insert<A3: P1>(id: String, _ value: A3)  -> any P5<A3> {
+        self.insert(id: id, value, replace: true)
+    }
+}
+

validation-test/compiler_crashers_2_fixed/rdar98615954.swift

@@ -0,0 +1,42 @@
+// RUN: %target-swift-frontend -emit-ir %s
+
+public typealias OnValue<Value> = () -> Value
+
+public protocol SubjectProtocol<Value> {
+    associatedtype Value
+
+    func value() -> Value
+    func onValue(_ onValue: @escaping OnValue<Value>) -> any SubjectProtocol<Value>
+}
+
+class Subject<Value>: SubjectProtocol {
+    var _onValue: OnValue<Value>?
+
+    init(_ onValue: OnValue<Value>?) {
+        self._onValue = onValue
+    }
+
+    func value() -> Value {
+        if let onValue = self._onValue {
+            return onValue()
+        } else {
+            fatalError("Require Implementation")
+        }
+    }
+
+    func onValue(_ onValue: @escaping OnValue<Value>) -> any SubjectProtocol<Value> {
+        let subject = Subject(self._onValue)
+        subject._onValue = onValue
+
+        return subject
+    }
+}
+
+public func ExistentialSubject<Value>() -> any SubjectProtocol<Value> {
+    Subject(nil)
+}
+
+public func DebugSubject() {
+    ExistentialSubject().onValue { 0 }
+}
+