div_qr_1 interface

Torbjorn Granlund tg at gmplib.org
Tue Oct 22 17:28:23 CEST 2013

nisse at lysator.liu.se (Niels Möller) writes:

  > (3) Offet UP to avoid the offset in the loop.
  Should be straight forward. Or one could offset UN, but I think it's
  nice to be able to use dec / jnz for the loop.

There is plenty of execution bandwidth, so using 2 x lea, dec, jnz for
the loop control is no problem.  Only when one is decode (or dispatch,
retire) bandwidth constrained is indexing a good thing.

  Or is the obscure "loop" decrement and branch instruction useful?
I've hadrly ever used it.  IIRC, it can only reach -0x80..+0x7f from its


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