[Bug target/71338] New: [RL78] mulu instruction not used on G10

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71338

            Bug ID: 71338
           Summary: [RL78] mulu instruction not used on G10
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: olegendo at gcc dot gnu.org
                CC: dj at redhat dot com, nickc at redhat dot com
  Target Milestone: ---
            Target: rl78-elf

Support for the widening unsigned 8 bit x 8 bit -> 16 bit multiplication has
been added here
https://gcc.gnu.org/ml/gcc-patches/2013-05/msg00806.html

but then pulled out for G10 here
https://gcc.gnu.org/ml/gcc-patches/2014-08/msg01538.html

I could not find any reference for that.  RL78/G10 hardware manuals say that
the S1 core supports the mulu instruction.  There's even example source code in
'r01an1976ej0200_rl78g10' that shows how to utilize it for partial product
multiplication ...

Can anybody please clarify what's the matter?