[IRGen] Sign task resume context in swift_suspend_point.

rdar://72357371

Author: nate-chandler

lib/IRGen/GenFunc.cpp

@@ -2559,6 +2559,11 @@ llvm::Function *IRGenFunction::createAsyncSuspendFn() {
   auto *resumeAddr = Builder.CreateStructGEP(task, 4);
   Builder.CreateStore(resumeFunction, Address(resumeAddr, ptrAlign));
   auto *contextAddr = Builder.CreateStructGEP(task, 5);
+  if (auto schema = IGM.getOptions().PointerAuth.TaskResumeContext) {
+    auto authInfo = PointerAuthInfo::emit(suspendIGF, schema, contextAddr,
+                                          PointerAuthEntity());
+    context = emitPointerAuthSign(suspendIGF, context, authInfo);
+  }
   Builder.CreateStore(context, Address(contextAddr, ptrAlign));
   auto *suspendCall = Builder.CreateCall(
       IGM.getTaskSwitchFuncFn(),

test/Concurrency/Runtime/actor_counters.swift

@@ -6,8 +6,6 @@
 
 // Remove with rdar://problem/72439642
 // UNSUPPORTED: asan
-// Remove with rdar://problem/72357371
-// UNSUPPORTED: CPU=arm64e
 
 #if canImport(Darwin)
 import Darwin

test/Concurrency/Runtime/mainactor.swift

@@ -5,8 +5,6 @@
 
 // REQUIRES: OS=macosx || OS=ios
 // FIXME: should not require Darwin to run this test once we have async main!
-// Remove with rdar://problem/72357371
-// UNSUPPORTED: CPU=arm64e
 
 // for exit(:Int)
 #if canImport(Darwin)