[RL78] Fix encoding of divwu insn

[nick clifton]

Hi Kaushik,

> This is quite odd indeed. I too have the same document(R01US0015EJ0100 Rev.1.00)
> which is dated Jan 31 2011.

Hmm, it appears that Renesas revised the document, but did not later the 
release date or revision number.  Naughty Renesas.

> The software manual currently available on their website also has
> a [0xCE 0xFB 0x0B] encoded for the DIVWU instruction and has no mention of
> a DIVH instruction.
> http://documentation.renesas.com/doc/products/mpumcu/doc/rl78/r01us0015ej_rl78.pdf

Agreed.

> We came across this issue while testing some code on the G14 target which
> supports this instruction and the hardware seemed to behave inconsistently.
> The updated toolchain with this patch seemed to resolve our problems.

Fair enough, hardware trumps paper.


 >	gas/Changelog
 >	* rl78-parse.y: Fix encoding of divwu insn.

This part of the patch is approved, but before you apply it, please 
could you add a comment mentioning the change of opcode encoding and the 
fact that different versions of the Software Manual exist with the same 
revision number.

 >	opcodes/Changelog
 >	* rl78-decode.c: Fix encoding of divwu insn.
 >	* rl78-decode.opc: Ditto.

I think that it would be better to leave the "case 0x04:" statements in 
place - but maybe have them decode to "divwu <old-encoding>" or 
something like that.  (0xce/0xfb/0x04 is not used for anything else, yes 
?)

Adding the new case values is approved.

Cheers
   Nick