On Fri, Feb 12, 2016 at 01:15:11PM +0100, Bernd Schmidt wrote:
> >Ah, indeed looks like a dup. Let's go with your version which had
> >feedback from Bernd already. Might want to add my testcase (w/o the
> >runtime outcome test).
>
> Actually, Richard I was just looking at Jakub's second patch and I think
> yours is better - on the first round of review I didn't notice that the
> convert_modes code is there and is documented to deal with the CONST_INT
> problem. If it completed testing I think you should commit it.
That patch doesn't look right to me. The code is there not just for shifts,
but also for non-shifts, and for non-shifts, we know the arguments are in
mode, we also know unsignedp, so if needed convert_modes can perform
zero or sign extension. IMHO it is just shifts/rotates that are
problematical, because what the second operand mode is and whether it is
unsigned
or signed is just less well defined, and then various backends have various
requirements on it. Also, on some target for shift/rotate xmode1 might be
already equal to mode, and in that case convert_modes would not be called,
but still the CONST_INT might be originally from yet another mode and we'd
still ICE.
Jakub
