UPX just compresses the machine code on disk and decompresses it in memory before execution. WebAssembly executables are delivered via http and can just be comp

UPX just compresses the machine code on disk and decompresses it in memory before execution. WebAssembly executables are delivered via http and can just be compressed with gzip/brotli etc as part of the existing protocols, completely transparently to WA itself. Granted, UPX is specialized so it might have a slight compression edge over gzip. But layering UPX over WA will require three passes over all the code before it's ready to start (1: browser downloads and executes UPX stub and compressed data. 2: UPX unpacks and reloads uncompressed code. 3: browser re-compiles and executes unpacked code again.) This would completely decimate browsers attempts to make WA startup fast like firefox's streaming compiler [1] that starts compiling it before it's even done downloading. [1]: https://hacks.mozilla.org/2018/01/making-webassembly-even-faster-firefoxs-new-streaming-and-tiering-compiler/ https://hacks.mozilla.org/2018/01/making-webassembly-even-fa...