A Refined Decompiler to Generate C Code with High Readability

As a key part of reverse engineering, decompilation plays a very important role in software security and maintenance. Unfortunately, most existing decompilation tools suffer from the low accuracy in identifying variables, functions and composite structures, which results in poor readability. To address these limitations, we present a practical decompiler called C-Decompiler for Windows C programs that (1) uses a shadow stack to perform refined data flow analysis, and (2) adopts inter-basic-block register propagation to reduce redundant variables. Our experimental results illustrate that on average C-Decompiler has the highest total percentage reduction of 55.91%, lowest variable expansion rate of 55.79% in the three tools, and the same Cyclomatic Complexity as the original source code for each test application. Furthermore, in our experiment, C-Decompiler is able to recognize functions with lower false positive and false negative rate. In the studies, we show that C-Decompiler is a practical tool to produce highly readable C code.