Re: [PATCH v2 0/5] MR283: vkd3d-shader/dxil: Implement DX instruction StoreOutput.

[Giovanni Mascellani (＠giomasce)]

Giovanni Mascellani (@giomasce) commented about libs/vkd3d-shader/dxil.c:
>  return value_count;
>
> }
>
> +static size_t sm6_parser_get_value_index(const struct sm6_parser *sm6, uint64_t idx)
> +{
> - size_t i;
> -
> - /* The value relative index is apparently always 32 bits, so forward refs do not
> -
> * have the upper 32 bits set to 1. */
> - i = (uint32_t)sm6->value_count - (uint32_t)idx;
> -
> - /* This may underflow to produce a forward reference, but it must not exceeed the final value count
> -
> * and should not have > 32 significant bits. */
> - if ((idx > UINT32_MAX && idx < UINT64_MAX - INT32_MAX) || i >= sm6->cur_max_value)

Hhm, from the comment it seems that `idx` should always be contained in 32 bit, but the code apparently allows it to be bigger, provided that it's larger than `UINT64_MAX - INT32_MAX`. What's the actual intent?