simd support (neon) for arm64-v8a?

[Wuqiman]

hello, can simd support (neon) for arm64-v8a currently?

[ngzhian]

Yes it can! Are you facing any issues with it?

[Wuqiman]

Yes it can! Are you facing any issues with it?

hello, It's very good! Where do i go to find examples and documentation for arm64-v8a? Thank you very much~

[ngzhian]

You don't need to do anything specific to use arm64-v8a, if you run Wasm containing SIMD on a Chrome browser (with the experimental simd flag turned on) on an arm64 system, it will automatically be using NEON instructions.

[penzn]

@Wuqiman what runtime are you using? There is implementation status doc for a few runtimes, Also Wasmer supports SIMD, though I don't know if it works on Arm.

[huqinghao]

@ngzhian For C++ codes, SIMD instructions are different on different architectures ,i.e. using NEON on Arm and using SSE SIMD on X86.

if you run Wasm containing SIMD on a Chrome browser (with the experimental simd flag turned on) on an arm64 system, it will automatically be using NEON
instructions.

does this means that I could just write NEON instructions on C++ codes, and it will be compiled into wasm correctly, then it can be runned on a Chrome browser on an arm64 system.
Or there are wrapped SIMD instructions provided by WASM and these instructions can be compiled into wasm correctly. Any examples are welcomed.

[ngzhian]

Oh, I see what you mean, you will have to use the wasm simd intrinsics, like here https://emscripten.org/docs/porting/simd.html
An example of porting a project that is currently using SSE SIMD to Wasm SIMD is https://github.com/penzn/dSFMT-wasm , check out the commits to see how it was done.

[huqinghao]

Got it! Thanks you so much.