On Wed, 2009-12-23 at 10:11 +0530, Mohamed Shafi wrote:
> 2009/12/22 Richard Earnshaw <rearn...@arm.com>:
> >
> > On Mon, 2009-12-21 at 18:44 +0000, Paul Brook wrote:
> >> > > > I am doing a port in GCC 4.4.0 for a 32 bit target. As a part of
> >> > > > scheduling framework i have to write the move patterns with more
> >> > > > clarity, so that i could control the scheduling with the help of
> >> > > > attributes. Re-writting the pattern resulted in movsi pattern with 41
> >> > > > alternatives :(
> >> > >
> >> > > Use rtl expressions instead of alternatives. e.g. arm.md:arith_shiftsi
> >> >
> >> > Or use the more modern iterators approach.
> >>
> >> Aren't iterators for generating multiple insns (e.g. movsi and movdi) from 
> >> the
> >> same pattern, whereas in this case we have a single insn  that needs to 
> >> accept
> >> many different operand combinartions?
> >
> > Yes, but that is often better, I suspect, than having too fancy a
> > pattern that breaks the optimization simplifications that genrecog does.
> >
> > Note that the attributes that were requested could be made part of the
> > iterator as well, using a mode_attribute.
> >
>   I can't find a back-end that does this. Can you show me a example?
I think the mips port is currently the most comprehensive example for
use of iterators.

R.

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