Re: Merging CCP and VRP?

[Diego Novillo <dnovillo at redhat dot com>]

On Sun, Mar 27, 2005 at 08:08:43PM -0500, Kazu Hirata wrote:

> Also, if we are inserting ASSERT_EXPRs, it seems to be a good idea to
> run copy-prop before VRP.  Otherwise, we would end up with lots of
> 
There is a copy-propagation pass before VRP.  Or do you mean
right before?  Sure, the ordering of these passes is in eternal
flux anyway.

> Currently, we still have these even after copy prop because we don't
> allow copy propagation between const and non-const pointers, which I
> think is a bit too restrictive.
> 
I assume these are blocked by may_propagate_copy.  What's
blocking these?  Do they have different alias set numbers or do
we need a conversion from the const to the non-const version?

> > ISTR either stevenb or dberlin implementing a dom-order
> > propagation.  I think they got a minor speedup that could be
> > worth having.
> 
> Huh, whey I talked to them on IRC they didn't seem to have implemented
> this.  I'll try to get this issue one of these days.
> 
Maybe I'm thinking of someone else.  I do remember somebody
playing with this.  Oh, well, it doesn't matter.  It's easy
enough to change at anytime.


Diego.