Merge pull request #2626 from aschwaighofer/fix_swiftasync_transfer_coro_split

fix transfer of swiftasync parameter

Author: aschwaighofer

llvm/lib/Transforms/Coroutines/CoroSplit.cpp

@@ -475,7 +475,8 @@ static Function *createCloneDeclaration(Function &OrigF, coro::Shape &Shape,
   Function *NewF =
       Function::Create(FnTy, GlobalValue::LinkageTypes::InternalLinkage,
                        OrigF.getName() + Suffix);
-  NewF->addParamAttr(0, Attribute::NonNull);
+  if (Shape.ABI != coro::ABI::Async)
+    NewF->addParamAttr(0, Attribute::NonNull);
 
   // For the async lowering ABI we can't guarantee that the context argument is
   // not access via a different pointer not based on the argument.
@@ -883,8 +884,9 @@ void CoroCloner::create() {
     break;
   case coro::ABI::Async: {
     auto *ActiveAsyncSuspend = cast<CoroSuspendAsyncInst>(ActiveSuspend);
-    auto ContextArgIndex = ActiveAsyncSuspend->getStorageArgumentIndex();
-    if (OrigF.hasParamAttribute(ContextArgIndex, Attribute::SwiftAsync)) {
+    if (OrigF.hasParamAttribute(Shape.AsyncLowering.ContextArgNo,
+                                Attribute::SwiftAsync)) {
+      auto ContextArgIndex = ActiveAsyncSuspend->getStorageArgumentIndex();
       addAsyncContextAttrs(NewAttrs, Context, ContextArgIndex);
     }