This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [patch] MIPS - Adjust cost for mult/div when optimizing forsize.


On Mon, 2005-05-09 at 11:47 -0700, Eric Christopher wrote:
> On Mon, 2005-05-09 at 18:25 +0100, David Ung wrote:
> > When optimizing for size (-Os), the compiler often replaces a multiply
> > with a sequence of shifts and adds.  This is desirable for speed
> > optimizations, but not so when optimizing for size.
> > The following patch takes size into account when optimizing for size.
> > 
> > David.
> > 
> > 
> > 2005-05-09  David Ung  <davidu@mips.com>
> > 
> > 	* config/mips/mips.c (mips_rtx_costs): Adjust cost for mult/div
> > 	when optimizing for size by reflecting the number instructions
> > 	used instead of execution time.
> 
> I've got another patch in this area that I'll be committing in the next
> couple of days so I'd appreciate you holding off on this for a few days.
> 
> thanks.
> 
> -eric
> 

I too have some patches that's going to address more on the cost of
multiplier on various processors on the way.  This patch was just of
kick start to that.  If you have work that you are likely to commit
soon, I guess I can hold off the rest of our patches to a later date.

David.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]