You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: row_id_gen.rs
    path of file: ./repos/risingwave/src/stream/src/executor
    
    the code of the file until where you have to start completion: // Copyright 2024 RisingWave Labs
//
// 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
// limitati
    
    async fn execute_inner(mut self) {
        let mut upstream = self.upstream.take().unwrap().execute();

        // The first barrier mush propagated.
        let barrier = expect_first_barrier(&mut upstream).await?;
        yield Message::Barrier(barrier);

        #[for_await]
        for msg in upstream {
            let msg = msg?;

            match msg {
                Message::Chunk(chunk) => {
                    // For chunk message, we fill the row id column and then yield it.
                    let (ops, mut columns, bitmap) = chunk.into_inner();
                    columns[self.row_id_index] =
                        self.gen_row_id_column_by_op(&columns[self.row_id_index], &ops, &bitmap);
                    yield Message::Chunk(StreamChunk::with_visibility(ops, columns, bitmap));
                }
                Message::Barrier(barrier) => {
                    // Update row id generator if vnode mapping changes.
                    // Note that: since `Update` barrier only exists between `Pause` and `Resume`
                    // barrier, duplicated row id won't be generated.
                    if let Some(vnodes) = barrier.as_update_vnode_bitmap(self.ctx.id) {
                        self.row_id_generator = Self::new_generator(&vnodes);
                    }
                    yield Message::Barrier(barrier);
                }
                Message::Watermark(watermark) => yield Message::Watermark(watermark),
            }
        }
    }