On Tue, Jan 26, 2016 at 04:54:43PM +0100, Richard Biener wrote:
> > Somehow PR 65656 miscompiled:
> >
> > if (STATIC_CONSTANT_P (xi.precision > HOST_BITS_PER_WIDE_INT)
> > ? xi.len == 1 && xi.val[0] >= 0
> > : xi.precision <= HOST_BITS_PER_WIDE_INT)
> >
> > which turned the expression into true and hit
> >
> > val[0] = xi.to_uhwi () >> shift;
> > result.set_len (1);
>
> I think we need a better analysis as we use __builtin_constant_p
> elsewhere as well.
Yeah, it would be nice to understand the somehow and what exactly is gong
on.
So, what is xi.precision, is it variable or constant, what value does it
have, has __builtin_constant_p returned 1 when it was supposed to return 0?
But then there would be still the precision check.
What is xi.len and xi.val[0]?
Jakub
