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Re: [buildd] Etch?

On Fri, Aug 04, 2006 at 02:37:03PM +0200, Geert Uytterhoeven wrote:
> On Fri, 4 Aug 2006, Wouter Verhelst wrote:

> > * Using address register indirect with predecrement or postincrement mode
> >   on the stack pointer (A7) in byte context will increment resp.
> >   decrement the stack pointer with 2 bytes on classic 68k, but with 1
> >   byte on the ColdFire. Both still need to be aligned on two bytes,
> >   however. As a result, this addressing mode should be avoided; but I do
> >   not think that it is used very often.
> Hmm... So what happens if you push 1 byte on the stack, and an interrupt comes
> in?

does CF have distinct user and supervisor stack pointers? 

The push 1 byte to stack is not all that useless but can be avoided.
Grepped through code and gcc doesn't do it, it is only used inside
the kernel in 68040 FPU support routines afaics. I hope there is not
more handwritten asm code with this oddity lurking


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