On Thu, 5 Jul 2007, Roman Zippel wrote:
> Hi,
>
> On Thu, 5 Jul 2007, Richard Guenther wrote:
>
> > > How should this be optimized within the context of your canonicalization?
> >
> > For example by making fold_plusminus_mult_expr do what its comment
> > suggest, "No identical multiplicands; see if we can find a common
> > power-of-two factor ..."
> >
> > Can you try the following and see if it helps m68k?
>
> The problem isn't specific to m68k, it's a problem for i386 and probably
> others as well.
> The patch is unfortunately no improvement, the problem is the canonical
> form for addresses is (p * c) + o, which directly conflicts with yours.
For me both canonicalizations generate
movl 8(%ecx,%edx,4), %eax
addl 4(%ecx,%edx,4), %eax
Richard.
