defer: enable loop lowering

runtime/internal/runtime/defer_tls.go

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2025 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package runtime
+
+import "github.com/goplus/llgo/runtime/internal/clite/tls"
+
+var deferTLS = tls.Alloc[*Defer](func(head **Defer) {
+	if head != nil {
+		*head = nil
+	}
+})
+
+// SetThreadDefer associates the current thread with the given defer chain.
+func SetThreadDefer(head *Defer) {
+	deferTLS.Set(head)
+}
+
+// ClearThreadDefer resets the current thread's defer chain to nil.
+func ClearThreadDefer() {
+	deferTLS.Clear()
+}