Switch @_unsafeSendable and @_unsafeMainActor tests to @_predatesConcurrency

Author: DougGregor

test/ClangImporter/objc_async.swift

@@ -76,7 +76,7 @@ func testSlowServerSynchronous(slowServer: SlowServer) {
 
   slowServer.overridableButRunsOnMainThread { s in
     print(s)
-    onlyOnMainActor() // okay because parameter has @_unsafeMainActor
+    onlyOnMainActor() // okay because parameter is @MainActor
   }
 
   let _: Int = slowServer.overridableButRunsOnMainThread // expected-error{{cannot convert value of type '(((String) -> Void)?) -> Void' to specified type 'Int'}}

test/Concurrency/concurrent_value_checking.swift

@@ -136,7 +136,7 @@ func testConcurrency() {
   }
 }
 
-func acceptUnsafeSendable(@_unsafeSendable _ fn: () -> Void) { }
+@_predatesConcurrency func acceptUnsafeSendable(_ fn: @Sendable () -> Void) { }
 
 func testUnsafeSendableNothing() {
   var x = 5

test/Concurrency/global_actor_inference.swift

@@ -505,9 +505,9 @@ func acceptClosure<T>(_: () -> T) { }
 }
 
 // ----------------------------------------------------------------------
-// Unsafe main actor parameter annotation
+// Main actor that predates concurrency
 // ----------------------------------------------------------------------
-func takesUnsafeMainActor(@_unsafeMainActor fn: () -> Void) { }
+@_predatesConcurrency func takesUnsafeMainActor(fn: @MainActor () -> Void) { }
 
 @MainActor func onlyOnMainActor() { }
 

test/Inputs/clang-importer-sdk/usr/include/ObjCConcurrency.h

@@ -4,7 +4,6 @@
 #pragma clang assume_nonnull begin
 
 #define MAIN_ACTOR __attribute__((__swift_attr__("@MainActor")))
-#define MAIN_ACTOR_UNSAFE __attribute__((__swift_attr__("@_unsafeMainActor")))
 
 #define NS_EXTENSIBLE_STRING_ENUM __attribute__((swift_wrapper(struct)));
 typedef NSString *Flavor NS_EXTENSIBLE_STRING_ENUM;
@@ -86,7 +85,7 @@ typedef void (^CompletionHandler)(NSString * _Nullable, NSString * _Nullable_res
 -(void)asyncImportSame:(NSString *)operation completionHandler:(void (^)(NSInteger))handler;
 -(void)asyncImportSame:(NSString *)operation replyTo:(void (^)(NSInteger))handler __attribute__((swift_async(none)));
 
--(void)overridableButRunsOnMainThreadWithCompletionHandler:(MAIN_ACTOR_UNSAFE void (^ _Nullable)(NSString *))completion;
+-(void)overridableButRunsOnMainThreadWithCompletionHandler:(MAIN_ACTOR void (^ _Nullable)(NSString *))completion __attribute__((swift_attr("@_predatesConcurrency")));
 - (void)obtainClosureWithCompletionHandler:(void (^)(void (^_Nullable)(void),
                                                      NSError *_Nullable,
                                                      BOOL))completionHandler
@@ -171,7 +170,7 @@ void doSomethingConcurrently(__attribute__((noescape)) __attribute__((swift_attr
 
 
 
-void doSomethingConcurrentlyButUnsafe(__attribute__((noescape)) __attribute__((swift_attr("@_unsafeSendable"))) void (^block)(void));
+void doSomethingConcurrentlyButUnsafe(__attribute__((noescape)) __attribute__((swift_attr("@Sendable"))) void (^block)(void)) __attribute__((swift_attr("@_predatesConcurrency")));
 
 
 MAIN_ACTOR MAIN_ACTOR __attribute__((__swift_attr__("@MainActor(unsafe)"))) @protocol TripleMainActor

test/SILGen/check_executor.swift

@@ -15,7 +15,7 @@ import _Concurrency
 
 func takeClosure(_ fn: @escaping () -> Int) { }
 
-func takeUnsafeMainActorClosure(@_unsafeMainActor _ fn: @escaping () -> Int) { }
+@_predatesConcurrency func takeUnsafeMainActorClosure(_ fn: @MainActor @escaping () -> Int) { }
 
 public actor MyActor {
   var counter = 0