[clang] [CIR] Add coroutine cleanup handling and update co_return semantics (PR #189281)

[via cfe-commits]

================
@@ -2874,6 +2874,48 @@ LogicalResult cir::AwaitOp::verify() {
   return success();
 }
 
+LogicalResult cir::CoReturnOp::verify() {
+  if (!getOperation()->getParentOfType<CoroBodyOp>())
+    return emitOpError("must be inside a cir.coro.body");
+  return success();
+}
+
+//===----------------------------------------------------------------------===//
+// CoroBody
+//===----------------------------------------------------------------------===//
+
+void cir::CoroBodyOp::getSuccessorRegions(
+    mlir::RegionBranchPoint point, SmallVectorImpl<RegionSuccessor> &regions) {
+  if (!point.isParent()) {
+    regions.push_back(RegionSuccessor::parent());
+    return;
+  }
+
+  regions.push_back(RegionSuccessor(&getBodyRegion()));
+}
+
+mlir::ValueRange
+cir::CoroBodyOp::getSuccessorInputs(RegionSuccessor successor) {
+  return ValueRange();
+}
+
+LogicalResult cir::CoroBodyOp::verify() {
+  if (!getOperation()->getParentOfType<FuncOp>().getCoroutine())
+    return emitOpError("enclosing function must be a coroutine");
+  return success();
----------------
Andres-Salamanca wrote:

No, it does not necessarily need to end with a `CoReturnOp`. There are cases where it cannot be terminated with a `CoReturnOp`, so I added support for allowing the body region to also be terminated using a `YieldOp`. Thanks for catching this!

https://github.com/llvm/llvm-project/pull/189281