Added temporary workaround for stack allocation optimization breaking isolated deinit tests in optimized mode

Author: nickolas-pohilets

test/Concurrency/Runtime/async_task_locals_isolated_deinit.swift

@@ -9,8 +9,6 @@
 // REQUIRES: concurrency_runtime
 // UNSUPPORTED: back_deployment_runtime
 
-// REQUIRES: gh76538
-
 import Swift
 import _Concurrency
 import Dispatch
@@ -128,6 +126,14 @@ class ClassNoOp: Probe {
 
 let tests = TestSuite("Isolated Deinit")
 
+// Dummy global variable to suppress stack propagation
+// TODO: Remove it after disabling allocation on stack for classes with isolated deinit
+var x: AnyObject? = nil
+func preventAllocationOnStack(_ object: AnyObject) {
+  x = object
+  x = nil
+}
+
 if #available(SwiftStdlib 5.1, *) {
   tests.test("class sync fast path") {
     let group = DispatchGroup()
@@ -136,7 +142,7 @@ if #available(SwiftStdlib 5.1, *) {
       // FIXME: isolated deinit should be clearing task locals
       await TL.$number.withValue(42) {
         await AnotherActor.shared.performTesting {
-          _ = ClassNoOp(expectedNumber: 42, group: group)
+          preventAllocationOnStack(ClassNoOp(expectedNumber: 42, group: group))
         }
       }
     }
@@ -148,7 +154,7 @@ if #available(SwiftStdlib 5.1, *) {
     group.enter(1)
     Task {
       TL.$number.withValue(99) {
-        _ = ClassNoOp(expectedNumber: 0, group: group)
+        preventAllocationOnStack(ClassNoOp(expectedNumber: 0, group: group))
       }
     }
     group.wait()
@@ -162,7 +168,7 @@ if #available(SwiftStdlib 5.1, *) {
       TL.$number.withValue(99) {
         // Despite last release happening not on the actor itself,
         // this is still a fast path due to optimisation for deallocating actors.
-        _ = ActorNoOp(expectedNumber: 99, group: group)
+        preventAllocationOnStack(ActorNoOp(expectedNumber: 99, group: group))
       }
     }
     group.wait()
@@ -174,7 +180,7 @@ if #available(SwiftStdlib 5.1, *) {
     Task {
       TL.$number.withValue(99) {
         // Using ProxyActor breaks optimization
-        _ = ProxyActor(expectedNumber: 0, group: group)
+        preventAllocationOnStack(ProxyActor(expectedNumber: 0, group: group))
       }
     }
     group.wait()
@@ -184,8 +190,8 @@ if #available(SwiftStdlib 5.1, *) {
     let group = DispatchGroup()
     group.enter(2)
     Task {
-      _ = ActorNoOp(expectedNumber: 0, group: group)
-      _ = ClassNoOp(expectedNumber: 0, group: group)
+      preventAllocationOnStack(ActorNoOp(expectedNumber: 0, group: group))
+      preventAllocationOnStack(ClassNoOp(expectedNumber: 0, group: group))
     }
     group.wait()
   }

test/Concurrency/voucher_propagation.swift

@@ -266,6 +266,14 @@ func adopt(voucher: voucher_t?) {
   os_release(voucher_adopt(os_retain(voucher)))
 }
 
+// Dummy global variable to suppress stack propagation
+// TODO: Remove it after disabling allocation on stack for classes with isolated deinit
+var x: AnyObject? = nil
+func preventAllocationOnStack(_ object: AnyObject) {
+  x = object
+  x = nil
+}
+
 let tests = TestSuite("Voucher Propagation")
 
 if #available(SwiftStdlib 5.1, *) {
@@ -436,15 +444,15 @@ if #available(SwiftStdlib 5.1, *) {
       Task {
         await AnotherActor.shared.performTesting {
           adopt(voucher: v1)
-          _ = ClassWithIsolatedDeinit(expectedVoucher: v1, group: group)
+          preventAllocationOnStack(ClassWithIsolatedDeinit(expectedVoucher: v1, group: group))
         }
         await AnotherActor.shared.performTesting {
           adopt(voucher: v2)
-          _ = ActorWithSelfIsolatedDeinit(expectedVoucher: v2, group: group)
+          preventAllocationOnStack(ActorWithSelfIsolatedDeinit(expectedVoucher: v2, group: group))
         }
         await AnotherActor.shared.performTesting {
           adopt(voucher: v3)
-          _ = ActorWithDeinitIsolatedOnAnother(expectedVoucher: v3, group: group)
+          preventAllocationOnStack(ActorWithDeinitIsolatedOnAnother(expectedVoucher: v3, group: group))
         }
       }
       group.wait()
@@ -459,11 +467,11 @@ if #available(SwiftStdlib 5.1, *) {
       Task {
         do {
           adopt(voucher: v1)
-          _ = ActorWithDeinitIsolatedOnAnother(expectedVoucher: v1, group: group)
+          preventAllocationOnStack(ActorWithDeinitIsolatedOnAnother(expectedVoucher: v1, group: group))
         }
         do {
           adopt(voucher: v2)
-          _ = ClassWithIsolatedDeinit(expectedVoucher: v2, group: group)
+          preventAllocationOnStack(ClassWithIsolatedDeinit(expectedVoucher: v2, group: group))
         }
       }
       group.wait()