75% is a stretch. The last time I tested it, it was ~50% of my native program despite my best efforts, with AOT. Which is still good btw, just not as constantly advertised.
My colleague has been doing some stonking work with it, he claims its about 70% as fast, I was rounding up for safety!
That's pretty good if you ask me! I was using an image encoder that had a WebAssembly SIMD CMake option, which is nice, but it only had half of native performance. I suppose it will continue to improve over time.
Depending on the browser and also when this was WASM SIMD could have been a pessimization. It added first with compatibility in mind and took/is taking awhile to reach full performance potential
This is not a typical app.
Encoding images is a pretty typical thing to do though?