[Bug target/78953] Errors in compiling Spec 2006 for power9

["meissner at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78953

Michael Meissner <meissner at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2016-12-29
                 CC|                            |dje at gcc dot gnu.org,
                   |                            |segher at gcc dot gnu.org,
                   |                            |wschmidt at gcc dot gnu.org
           Assignee|unassigned at gcc dot gnu.org      |meissner at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #1 from Michael Meissner <meissner at gcc dot gnu.org> ---
A quick glance at the code, shows that the V4SImode register is a traditional
floating point register, but the splitter for vsx_extract_<mode>_p9 requires
the register to be a traditional altivec register.

I suspect vsx_extract_v4si_p9 is called from vsx_extract_si.  The later has a
constraint (wJ) that allows the operand to go in traditional floating registers
in addition to Altivec registers (v).