On Thu, Oct 22, 2020 at 12:36 AM Segher Boessenkool
<seg...@kernel.crashing.org> wrote:
>
> On Wed, Oct 21, 2020 at 04:43:29PM +0100, Richard Sandiford wrote:
> > Hongtao Liu <crazy...@gmail.com> writes:
> > > + poly_uint64 nunits
> > > + = GET_MODE_NUNITS (GET_MODE (SUBREG_REG (trueop0)));
> > > + rtx par = trueop1;
> > > + for (int i = 0; i != l1; i++)
> > > + {
> > > + rtx idx = XVECEXP (trueop1, 0, i);
> > > + if (!CONST_INT_P (idx)
> > > + || maybe_ge (UINTVAL (idx) + subreg_offset, nunits))
> > > + return 0;
> > > + }
> >
> > I think the previous version was better. We shouldn't assume that
> > further simplification rules will fail just because the conditions
> > for this rule haven't been met.
>
> Yes. My suggestion was to factor this big piece of code to a separate
> function, and do an early return from *that*.
>
> The patch is okay for trunk without that, with the clumsy booleans.
> Thanks Hongtao!
>
>
> Segher
Thank you both for the review, I'll commit the patch with *bool success* keeped.
--
BR,
Hongtao
