[PATCH] Add MIPS ufr macro instruction

[Andrew Bennett]

> On Sun, 24 Nov 2013, Richard Sandiford wrote:
> 
> > The problem with using ufr for disassembly is that AFAICT it isn't
> > mentioned in the manuals.  People disassembling pass-me-downs might
> > struggle to know what it means.  Maybe the ideal would be to disassemble
> > the CTC1 normally and add a comment "; ufr [01]" next to it.  But that's
> > probably make-work.
> > 
> > So TBH I preferred your original patch.
> > 
> > There haven't been any more objections, so if you're still OK with the
> > original version, I suggest we go with that.  I can apply it for you if so.
> 
>  Apologies for late coming, I missed this thread.  I object.  I think it 
> would make more sense if we followed the practice already established with 
> CP0 register names and instead defined cooked names for CP1 control 
> registers as well.  E.g.:
> 
> 	ctc1	$0, $c1_ufr
> 	ctc1	$0, $c1_unfr
> 	cfc1	$2, $c1_ufr
> 
> or suchlike.  I think it would be more obvious, user friendly (including 
> disassembly) and consistent.  If we wanted $0 implied for cases where 
> applicable we could define single-argument aliases, e.g.:
> 
> 	ctc1	$c1_ufr
> 	ctc1	$c1_unfr
> 
> preferably as macros as far as I'm concerned (although I'm not too
> enthusiastic about such aliases in the first place).
> 
>  Of course we'd add the rest at the same time too, i.e. $c1_fir, $c1_fcsr, 
> etc.
> 
>  Thoughts?

I like this solution.  Firstly, it makes it much easier to see what the c[ft]c1
instruction is actually doing when either assembling or disassembling.  Secondly, 
it is clear when a ufr instruction is being used, so I don't think it requires the 
need to have an explicit ufr macro.

If everyone is happy with this I will rework the patch, and post it back on to
the list.


Regards,



Andrew


Andrew Bennett
Software Design Engineer, MIPS Processor IP
Imagination Technologies Limited
t: +44 (0)113 2429814
www.imgtec.com