GCC: Inefficient register usage?

[Uvarov Sergey]

I'm still using gcc 2.7.2.3 and quite happy with it. But it produces the
same ugly code for the Christopher's example:

        moveb -2:w,d0
        orb #64,d0
        moveb d0,-2:w

So I think that the problem existed before the EGCS initiative. Look for
Kai Ruottu's letter "volatile again" from 27 Jan 2000 to get more
information.

	Sergey

On Fri, 25 Aug 2000, Mark Powell wrote:

> I have noticed a definite worsening of gcc's optimisation for the m68k
> target (and related targets such as ColdFire) since the EGCS initiative,
> i.e. versions since 2.8. I guess it is due to reworkings of the gcc
> internals to produce better code for the Pentiums and Sparcs. I remember one
> large piece of work in the early days of EGCS was the "Haifa scheduler". I
> don't know what it effect it might have had, but something like that may be
> the cause of the deterioration in 68k optimisation.
> 
> I wonder if there is any switch to revert to older behaviour. Any GCC gurus
> out there able to comment?
> 




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