On Tue, Mar 12, 2019 at 12:43:29PM +0100, Jakub Jelinek wrote:
> On Mon, Mar 04, 2019 at 10:04:01AM +0100, Jakub Jelinek wrote:
> > The first one uses constraints and no C code in the output, I believe it is
> > actually more expensive for compile time, because if one just reads what
> > constrain_operands needs to do for another constraint, it is quite a lot.
> > I've tried to at least not introduce new constraints for this, there is no
> > constraint for number 1 (or for number -1).
> > The Pu constraint is thumb2 only for numbers 1..8, and the alternative uses
> > I constraint for the negation of it, i.e. -8..-1, only -1 from this is
> > valid for I. If that matches, we emit adds with #1, otherwise just prefer
> > subs over adds.
> >
> > The other swaps the alternatives similarly to the above, but for the special
> > case of desirable adds with #1 uses C code instead of another alternative.
> >
> > Ok for trunk (which one)?
>
> I'd like to ping these patches:
>
> > 2019-03-04 Jakub Jelinek <ja...@redhat.com>
> >
> > PR target/89506
> > * config/arm/arm.md (cmpsi2_addneg): Swap the alternatives, add
> > another alternative with I constraint for operands[2] and Pu
> > for operands[3] and emit adds in that case, don't use C code to
> > emit the instruction.
>
> or:
>
> > 2019-03-04 Jakub Jelinek <ja...@redhat.com>
> >
> > PR target/89506
> > * config/arm/arm.md (cmpsi2_addneg): Swap the alternatives and use
> > subs for the first alternative except when operands[3] is 1.
Ping.
Jakub
