Fix rare crash caused by get method of proxy object (#5129)

This fixes #5101
In rare cases the proxy object could get used after
being incorrectly removed by the gc

Add stack checks to the start of all function calls

JerryScript-DCO-1.0-Signed-off-by: Máté Tokodi mate.tokodi@szteszoftver.hu

tests/jerry/regression-test-issue-5101.js

@@ -0,0 +1,32 @@
+// Copyright JS Foundation and other contributors, http://js.foundation
+//
+// 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.
+
+var iter = 100;
+async function f0() {
+    iter--;
+    function f6() {
+        return f0;
+    }
+    var proxy_handler = {
+        "get": f0,
+    };
+
+    f0.__proto__ = new Proxy(f6, proxy_handler);
+
+    if ((iter >= 0)) {
+        var v12 = f0();
+    }
+    return f0;
+}
+f0();