I. Introduction
With the continuous growth in the scale and complexity of software, software developers expend a substantial amount of time and effort manually writing source code. This phenomenon presents challenges for the software services industry, necessitating improved tools to assist in code development. The purpose of code generation is to automatically produce source code that aligns with given descriptions based on provided natural language input. Today, deep learning technology has successfully been applied to automatic code generation [1]–[3]. Models based on deep learning take natural language (NL) descriptions as input and produce corresponding source code as output. These models are trained on corpora containing genuine NL-Code pairs. Once trained, the models can autonomously generate code based on new NL descriptions. Currently, the prevailing code generation models encompass: sequence-based models, tree-based models, and pre-trained models. However, this single-step approach, where code can be generated using a generator in a single step, does not always yield a high level of compatibility with the target code.