Re: RFA: PowerPC sim & GDB: use fixed register numbering

Andrew Cagney
2004-08-04T17:33:45Z

> Andrew Cagney <cagney@gnu.org> writes:
>
>>>> > Andrew Cagney <cagney@gnu.org> writes:
>>>> >
>>>
>>>>>> >>> Have a look at the other sim-*.h files, you'll notice that most define
>>>>>> >>> an enum namespace and not a series of magic constants. Can we expand
>>>>>> >>> the table so that the constants aren't needed?
>>>
>>>> > Is this going in the right direction?
>>
>>>
>>> Yes, that should go in.
>
>
> Okay, committed. Thanks to you and Kevin for the review.

Ok,

> The old code, which did an under-the-covers call into gdb to map number -> name, was bad and definitly needed to be replaced. The above though could still do with some work - too much on the magic of those numbers in gdb/sim-ppc.h :-(
>
> Anyway, lets first get the enum in place.

Since we've nailed the enum, what should we do about the sim/ppc?

>>> What's your plan with SPRs?
>
>
> I think it's best to use the SPR numbers assigned by the ISA to
> identify them. Trying to keep tables based on automatically assigned
> enum values in sync would take a lot of work, for little gain, since
> ISA SPR numbers are (obviously) unambiguous within any particular PPC
> variant.

Which is a change from the status quo. That was doing things based on
the ISA's register name. Which ever.

> At the moment, the sim doesn't support any SPRs from different PPC
> variants whose numbers clash. There'll be work needed there to handle
> that; I don't have any particular insights there.

Andrew