new auto-inc-dec pass

[Roman Zippel]

Hi,

On Tue, 6 Mar 2007, Joern Rennecke wrote:

> In http://gcc.gnu.org/ml/gcc/2007-03/msg00128.html, you wrote:
> > One case is about multiple increments, the tree optimizer merges them and
> > increments the register only once, so if one only looks at the size of the
> > pointer value one misses them, e.g. something like this:
> >
> > 	(set (mem (reg)) (x))
> > 	(set (mem (plus (reg) (const_int 4))) (x))
> > 	(set (reg) (plus (reg) (const_int 8))
> 
> The patches attached to PR20211 handle this case.

Hmm, it seems to do a bit more. I have to agree with the last comment 
insofar, that regmove.c is probably not the best place for this. Most of 
the auto-inc-dec business should be done before combine.

bye, Roman