The V8 JavaScript engine, used in Chrome and Node.js, compiles JavaScript to bytecode executed by its Ignition interpreter. While bytecode is an intermediate representation, recovering high-level JavaScript semantics from it is nontrivial due to implicit type handling, control flow compression, and optimization metadata. This paper presents the design and implementation of a static decompiler for V8’s bytecode (version 9.0+). We analyze the bytecode structure, map instructions to abstract syntax tree nodes, reconstruct control flow, and handle edge cases like exception handlers and closure captures. Evaluation on real-world JavaScript snippets shows correct decompilation for 85% of tested functions, with remaining challenges due to hidden class transitions and deoptimization points. We discuss applications in malware analysis, legacy code recovery, and debugging.
"We have the destination," Elias said, his fingers flying across the keys to block the traffic. v8 bytecode decompiler