Re: [PATCH 0/1] MR340: vkd3d-shader/hlsl: Document some possibly obscure HLSL opcodes.

[Zebediah Figura (＠zfigura)]

Zebediah Figura (@zfigura) commented about libs/vkd3d-shader/hlsl.h:
>  HLSL_OP2_NEQUAL,
>  HLSL_OP2_RSHIFT,
>
> - /* DP2ADD(a, b, c) computes the scalar product of a.xy and b.xy,
> -
> * then adds c. */
> HLSL_OP3_DP2ADD,
> - /*  LERP(a, b, c) computes a * (1-z) + b * z or, equivalently,
> -
> *  a + z * (b - c). */

I think we can get rid of LERP. We don't use it and I don't anticipate we're going to.

sm1 has an opcode "lrp", but I can't get the native compiler to generate it. Probably it's meant for assembly only. We may be safest not generating it in that case, although I'm not really sure.

Frankly, even if we do output it, we may want that to be a raising pass on the vsir.