Re: AW: [avr-libc-dev] Improved optimizer for mixed 32 / 16 / 8 bit expressions

[E. Weddington]

Björn Haase wrote:

> Hi,
>
>  
>
> > Paul Schlie wrote
> >
> > Very nice, out of curiosity, whas this done entirely with .md rtl
> > optimization, or improving the minimal type size representation
> > within the compiler's front/middle end? (or a little of both?)
> >    
>
> sorry for replying a bit late. The changes that I have implemented so-far
> are restricted to
> the machine definition.
>
> What I have been doing is something rather tedious. I have made use of a
> well-known
> principle. The people that wrote the avr-port already have made use of it.
>
>
> <good stuff snipped>
>
> I have rechecked the changes for some days and I will post my suggestions in
> the .md this evening.
>
>  

When you post your changes, please CC both of the GCC AVR maintainers: 
Denis Chertykov and Marek Michalkiewicz (you can get their email 
addresses in the MAINTAINERS file in the GCC source code). They will 
both be very interested in this.

*If* it shows that your changes improved code on all cases, this might 
be a good time to see if it can be put into the upcoming GCC 4.0.0.

IMO, any changes that you make that reduce code size, *even at the 
expense of increasing compile time*, would be preferred. AVR projects 
are generally small enough that compile time is not a factor, but the 
size of the resulting code is way more important.

Thanks for doing this work! :-)

Eric