howto-wasm-minimal VS matrix-algebra

I'm particularly curious on what parts cheerp adds to their clang+llvm base. Presumably it's something like the C standard target library for WASM/JS?

For reference, here's examples of what you could do with the baseline clang with wasm (but not JS?) [1] [2] [3], referenced from a similar thread on HN.

[1] https://github.com/ern0/howto-wasm-minimal

[2] https://github.com/robrohan/wefx

[3] https://github.com/PetterS/clang-wasm

For future readers, this is the code that is being referred:

https://github.com/ern0/howto-wasm-minimal/blob/master/inc.c...

It should be:

   uint32_t gray = 0.299 * ptr[i] + 0.587 * ptr[i+1] + 0.114 * ptr[i+2];

This uses a strange "link broker", the link behind this is pointing to https://github.com/ern0/howto-wasm-minimal