Re: SH5 simulator contribution

[Andrew Cagney <ac131313 at cygnus dot com>]

>  Andrew> Unless the new simulator gains sh-dsp support, the sim directory will 
>   Andrew> need to be configurable so that the user can select either the DSP xor 
>   Andrew> the SH5 simulator.  That, I suspect, is going to get messy.  I think GDB 
>   Andrew> should be able to assume a single SH remote-sim interface but here, I 
>   Andrew> suspect, it is currently contending with two different interfaces :-(
> 
> Hence, this is why the sh5 sim is only configured when the target is
> sh64-*-elf.


Er, humor me.

The sim/sh simulator has a specific register name / number / size 
mapping and sh-elf-gdb knows how to use it.

This new sim/sh5 simulator has a different register / name / size 
mapping and this difference is covered up by GDB.  (I note the addition 
of the sim-sh64.h file which is in itself a very good move).

The MIPS (unintentionally) went down this path and ever since the MIPS 
has been trying to claw its way out of the resultant mess :-(  Given 
this, I think it would be better to just eliminate one of the 
simulators.  Failing that, ensure that at least the two simulators 
complied to an identical register name/number/size interface.

Would it possible to get this new SH simulator to support the sh-dsp 
instructions (there can't be that many of them) so that the old 
simulator can be retired?

More as a wish list, would it also be possible to have separate but 
integrated simulators for at least the few most recent SH variants - 
like mn10300 and am33.  I suspect this simulator was generated so it 
shouldn't be too hard.

Andrew