[PATCH v2] Support powerpc64le-linux platform

[Torbjorn Granlund]

"Ulrich Weigand" <uweigand at de.ibm.com> writes:

  I've now implemented your suggestion to add an optional 'toc' parameter,
  modeled after the alpha 'gp' parameter.  I think I got all places where
  this needs to be added; in general, I've not found any direct use of r2
  in assembler code, except for those that come in via use of the LEA(L)
  or CALL macros.
  
Thanks!

I believe we use macros for all of these, since that's how the asm
sources become portable.

  When building for the v1 ABI, the 'toc' parameter is simply ignored.
  I've had to likewise change PROLOGUE_cpu for darwin and aix to accept
  and ignore the 'toc' parameter.
  
You work like a fully qualified GMP hacker.  :-)

  Re-tested on powerpc64le-linux, powerpc64-linux, and powerpc64-ibm-aix
  with no regressions.  I don't have a Darwin system to test on,
  unfortunately, but since the change is identical to the AIX change,
  it seems unlikely to be broken ...
  
  Does this look OK?
  
It does indeed.

We need to understand the assignment status better.  That unfortunately
probably means that we need to wait out the FSF copyright clerks.

  OK, in that case the base OS question remains.  Right now, it seems
  the easiest choice is to use the openSUSE experimental build; they
  already have a (small) install image ready to run.  See "Run It":
  https://en.opensuse.org/openSUSE:PowerLE
  
I tried many qemu variants (including all recent releases) on a PC, but
none indeed worked.  The page tells us that we "need to have all VSX
patches applied for this to work" which presumably none of the tested
qemus do.  (I have no idea what "VSX patches" could be.  I know that the
moon's phases and luck play a vital parts in striking a non-broken
qemu...)

I'll rely on our testing for now.

Torbjörn

"Microsoft's worst disservice to mankind is not its business practices,
but that it has made people accept terrible software quality as if it
was an inevitability."