I came to much the same conclusion
On Tue, Mar 22, 2022 at 10:42 AM Richard Henderson
<richard.hender...@linaro.org> wrote:
>
> On 3/21/22 03:31, David Hildenbrand wrote:
> >> + for (i = 0; i < nelem; i++) {
> >> + if (s390_vec_read_element(v3, i, es) == 0) {
> >> + break;
> >> + }
> >> + }
> >> + if (i < substr_elen) {
> >> + substr_elen = i;
> >> + }
> >
> > Maybe combine both, I guess there is no need to search beyond substr_elen.
> >
> > substr_elen = MIN(substr_elen, nelem);
> > for (i = 0; i < substr_elen; i++) {
> > if (s390_vec_read_element(v3, i, es) == 0) {
> > substr_elen = i;
> > break;
> > }
> > }
>
> Yep.
>
> > We should do the MIN(substr_elen, nelem) maybe right when reading it
> > from v4.
>
> No, v4 does not get bounded until zs is set.
>
> >> + /* If ZS, look for eos in the searched string. */
> >> + if (zs) {
> >> + for (k = 0; k < nelem; k++) {
> >> + if (s390_vec_read_element(v2, k, es) == 0) {
> >> + eos = true;
> >> + break;
> >> + }
> >> + }
> >
> > I guess we could move that into the main search loop and avoid parsing
> > the string twice. Not sure what's better.
>
> I'd leave it here, so that we only do the strlen once. There's no obvious
> place within
> the the search loop that wouldn't wind up doing the strlen more than once.
>
>
> r~
