[PATCH] Improve System z support and add some tuning

[Torbjorn Granlund]

Mike Frysinger <vapier at gentoo.org> writes:

  > Awaiting paperwork, I committed basic s390x support to the mainline
  > repository.  I could do this work after I got an emulator up and running
  > on a system here.
  
  hercules i'm guessing ?
  
Yep, since networking is notworking in qemu-system-s390x.

  > (4) Should we perhaps use 64-bit limbs for the 31-bit ABI, when using a
  >     64-bit processor?  As far as I understand, this should work, and it
  >     would run much faster.  (This would be akin to the N32 MIPS ABI and
  >     the HPPA 2.0N ABI.)
  
  the biggest trouble we have in Gentoo with gmp is the automatic tuning it 
  does.  so as long as gmp's decision to pick 31-bit or 31-bit+64-bit is easily 
  controlled, this shouldn't be a big problem.  might have to declare a gmp-
  internal ABI name for this mode like 31-64 ?

Yep, something like that.  I am not 100% sure this can be done, I am new
to the wondrous world of System 390.

(Perhaps we ought to stop calling GMP's choice of ABI+limbsize for ABI.
We're abusing the term.)

-- 
Torbjörn