div_qr_1 interface

Niels Möller nisse at lysator.liu.se
Thu Oct 24 09:26:21 CEST 2013

Torbjorn Granlund <tg at gmplib.org> writes:

> Basically qp = up won't work, but qp = up + k for any positive k will?
> Does the C code share that property?

I think the C code has the same problem. Hmm, and it looks like in both
the C and asm code, it's only the first iteration, before the main loop,
which has this problem. Then it should be easy to fix, in the asm case,
it's one additional mov and not in the main loop.

> I think it would be good to fix that, since it is surely a common usage
> scenario.

I agree.

If/when the code is reorganized to delay the q stores (to avoid the "adc
Q2,8(QP, UN, 8)" instruction), I think the overlap issue will also get
fixed in the process.


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