Re: [rfc] trad-frame change

Andrew Cagney
2004-03-03T20:41:44Z

>>> So there are really two variants - o32sigreturn and rt_sigreturn (with
>>> constants computed from the architecture vector)?
>
>
> I don't see much point in distinguishing them that way, honestly. The
> difference between o32 sigreturn and o32 rt_sigreturn is about the same
> as the difference between n32 and n64. Sure, you could put the
> constants in the architecture tdep vector... but why bother?
>
> And it may be silly, but there's nothing stopping a theoretical
> hand-written program from using a different ABI's sigreturn syscall.

Like you said, theoretical - program for what is, not what might be, but
what ever.

>>>> >What would _really_ be nice would be a way to pass the kind from the
>>>> >sniffer (which really just calls PC_IN_SIGTRAMP) to the frame creation
>>>> >code... not have to read inferior memory to figure out which it is,
>>>> >twice.
>>
>>>
>>> I'll think about that, I may need to change the unwinder object anyway.
>>>
>>> Just remember that it is the number of unique addresses accessed (0 vs 1
>>> vs 2 ...) and not the number of times each address is accessed that is
>>> going to be important - multiple accesses to a single address can be
>>> handled with a cache.
>
>
> We really should turn on that cache someday.

Not that cache, a new one, yes, someday.

Andrew