[Bug libgcc/83103] New: Improve __mulkc3 and __divkc3 on Power9

[meissner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83103

            Bug ID: 83103
           Summary: Improve __mulkc3 and __divkc3 on Power9
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: libgcc
          Assignee: unassigned at gcc dot gnu.org
          Reporter: meissner at gcc dot gnu.org
  Target Milestone: ---

Right now, the __mulkc3 and __divkc3 functions that provide complex
multiply/divide support are built with the default cpu used for building
libgcc.  We should use the target_clones attribute to compile these functions
with -mcpu=power9, so that these functions are faster when run on power9
hardware.