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Re: [MiNT] Missing clobbered register in gemlib



> I'm really annoyed we don't have a small testcase showing that additional
> registers can be clobbered. For example, I have made some tests recently
> with the GEMDOS trap #1 on TOS 1.62, it never clobbers d2 and a2, they are
> backuped explicitly in the ROM.

That is consistent with what my most trusted (though unofficial)
documentation has to say about GEMDOS.
And if it was that way once, it is not likely to have changed (or lots
of software would likely have crashed).

> Anyway, since the official rule seems to be that d0-d2/a0-a2 can be

Has that really been verified?

The book I normally trust regarding these things does claim that
d0-d2/a0-a2 are indeed clobbered for BIOS and XBIOS, but that only
d0-d1/a0-a1 are for GEMDOS (and actually only a0 for everything except
SUPER).

The same book claims d0-d1/a0 are clobbered by the VDI and AES, which
is consistent with what I do in fVDI.
I very likely checked the ROMs to make sure this was the right thing to do.

/Johan