Re: [PATCH 2/4] target/riscv: Add right functions to set agnostic elements

[Richard Henderson <richard.henderson@linaro.org>]

On 3/19/24 11:57, Daniel Henrique Barboza wrote:
> This seems correct but a bit over complicated at first glance. I wonder if we have
> something simpler already done somewhere.
> 
> Richard, does ARM (or any other arch) do anything of the sort? Aside from more trivial
> byte swaps using bswap64() I didn't find anything similar.

No, nothing quite like.

> We recently posted a big endian related fix here:
> 
> [PATCH for 9.0 v15 03/10] target/riscv/vector_helper.c: fix 'vmvr_v' memcpy endianess
> 
> But not sure how to apply it here.

It's almost exactly the same, only with memset instead of memcpy.

     if (HOST_BIG_ENDIAN && idx % 8 != 0) {
         uint32_t j = ROUND_UP(idx, 8);
         memset(vd + H(j - 1), -1, j - idx);
         idx = j;
     }
     memset(vd + idx, -1, tot - idx);


I'll note that you don't need to change the api of vext_set_elems_1s -- so most of these 
patches are not required.


r~