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Re: [m68k] asm regression with 3.3/3.4/3.5
Richard Henderson <rth@redhat.com> writes:
> On Wed, May 12, 2004 at 12:13:17PM -0400, Ian Lance Taylor wrote:
> > In the asm statement, you said that the input _bn could be in any
> > register. You didn't say that it had to be in A6.
>
> Actually, he did -- he passed a hard register varible a6 to the asm.
> GCC is supposed to *not* cse hard register variables from asms
> specifically for this case -- making syscalls.
Hmmm, this case is not documented as far as I can see--in the docs I
don't see any special interaction between asm and local register
variables. And it doesn't appear to work.
> No, the likely problem here is that a6 is the frame pointer, and
> screwy things happen when you try to use it for other things.
He said that on his system, the frame pointer is A5.
I can recreate the problem using A4. It doesn't have anything to do
with the frame pointer.
Ian