Correct the region isolation rule for metatype extraction instructions

Now that metatypes might not be Sendable, we need the Assign rule for
operations that produce the metatype of a value or existential.

Author: DougGregor

lib/SILOptimizer/Analysis/RegionAnalysis.cpp

@@ -3002,6 +3002,8 @@ CONSTANT_TRANSLATION(IndexRawPointerInst, Assign)
 CONSTANT_TRANSLATION(InitExistentialMetatypeInst, Assign)
 CONSTANT_TRANSLATION(OpenExistentialMetatypeInst, Assign)
 CONSTANT_TRANSLATION(ObjCToThickMetatypeInst, Assign)
+CONSTANT_TRANSLATION(ValueMetatypeInst, Assign)
+CONSTANT_TRANSLATION(ExistentialMetatypeInst, Assign)
 
 // These are used by SIL to aggregate values together in a gep like way. We
 // want to look at uses of structs, not the struct uses itself. So just
@@ -3124,10 +3126,6 @@ CONSTANT_TRANSLATION(UnmanagedAutoreleaseValueInst, Require)
 CONSTANT_TRANSLATION(RebindMemoryInst, Require)
 CONSTANT_TRANSLATION(BindMemoryInst, Require)
 CONSTANT_TRANSLATION(BeginUnpairedAccessInst, Require)
-// Require of the value we extract the metatype from.
-CONSTANT_TRANSLATION(ValueMetatypeInst, Require)
-// Require of the value we extract the metatype from.
-CONSTANT_TRANSLATION(ExistentialMetatypeInst, Require)
 // These can take a parameter. If it is non-Sendable, use a require.
 CONSTANT_TRANSLATION(GetAsyncContinuationAddrInst, Require)
 

test/Concurrency/sendable_metatype.swift

@@ -66,3 +66,13 @@ nonisolated func passSendableToMainActorSmuggledAny<T: Sendable>(_: T.Type) asyn
   let x: Sendable.Type = T.self
   await acceptMetaOnMainActor(x)
 }
+
+// -------------------------------------------------------------------------
+// Existential opening
+// -------------------------------------------------------------------------
+nonisolated func passMetaSmuggledAnyFromExistential(_ qT: Q.Type) {
+  let x: Any.Type = qT
+  Task.detached { // expected-error{{risks causing data races}}
+    acceptMeta(x) // expected-note{{closure captures 'x' which is accessible to code in the current task}}
+  }
+}