Re: [Patch] Silent gcc 4.2.0 loop optimization bug with -O2

On Wed, 4 Jul 2007 22:56:03 +0200
Roman Divacky <rdivacky_at_freebsd.org> wrote:

> On Wed, Jul 04, 2007 at 11:01:48PM +0400, Andrey Chernov wrote:
> > On Wed, Jul 04, 2007 at 02:12:08PM +0200, Ed Schouten wrote:
> > > > Index: tree-ssa-loop-niter.c
> > > > ===================================================================
> > > > --- tree-ssa-loop-niter.c       (revision 126260)
> > > > +++ tree-ssa-loop-niter.c       (working copy)
> > > > _at__at_ -1747,6 +1747,12 _at__at_ infer_loop_bounds_from_undefined (struct
> > > >      {
> > > >        bb = bbs[i];
> > > > 
> > > > +      /* If BB is not executed in each iteration of the loop,
> > > > we cannot
> > > > +        use the operations in it to infer reliable upper bound
> > > > on the
> > > > +        # of iterations of the loop.  */
> > > > +      if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb))
> > > > +       continue;
> > > > +
> > > >        for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next
> > > > (&bsi)) {
> > > >           tree stmt = bsi_stmt (bsi);
> > > > 
> > > > I'm going to test this.
> > > > 
> > > ----- End forwarded message -----
> > > 
> > > I just tested the patch on my desktop and it seems to work. The
> > > test code now compiles like it should. Hopefully it will be part
> > > of 4.2.1.
> > 
> > Will be nice if this patch will be commited in instead of my 
> > sys.mk workaround. Alexander?
> 
> afaik they plan to release gcc 4.2.1 on July 13th, thats a week,
> possibly two ahead. maybe we can wait and import the 4.2.1 directly.
> 4.2.1 contains some more bug fixes so it would be worth it.
> 
> roman
4.2.1 import will happen when 4.2.1 is released.

-- 
Alexander Kabaev