WebAssembly direct instructions support?

[unit-404]

I planned to try development of game, based on Electron.js and Wasm64, and would to have direct Emscripten WebAssembly instructions intrinsics support.
Note: Wasm supports only 128-bit natively.
I just would to reduce conversion and optimization stagement while compiling or execution (simepp => SSE4.1 => WASM => Another SIMD in browser level). It while can be just simdpp => WASM => Correct SIMD.