This isn't very surprising. C compilers have developed all kinds of low level optimizations over decades, trying to extract the last bits of performance they co

This isn't very surprising. C compilers have developed all kinds of low level optimizations over decades, trying to extract the last bits of performance they could. In contrast, JIT compilers for JS focused on recovering missing type information through type inference and other low-hanging fruits. It's also the case that there's a lot more pressure on JS JITs to produce code fast, and so running multiple passes of low level optimizations was not desirable in a web context. This is somewhat bad news for WASM: better low level optimizations could mean longer compilation times. However, AFAIK, Chrome has been working on caching compiled code, so you may only have to compile WASM when it changes (or when you reinstall/update your browser).