Re: RFC: tracepoints: extend range of ax_trace_quick function

Jim Blandy
2007-10-29T16:11:48Z

Michael Snyder <msnyder at specifix.com> writes:
> On Fri, 2007-10-26 at 15:59 -0700, Jim Blandy wrote:
>> In order to get Linux kernel tracepoints working, I needed to make a
>> number of fixes in GDB. This is one such patch; the code which uses
>> the function's new range comes a bit later.
>>
>> Okay to commit?
>
> If I understand correctly, a trace_quick was formerly of size up to
> 8 bits. You've added a trace16 for objects up to 16 bits, and this
> just allows trace_quick to handle those objects by forwarding them
> to trace16.
>
> In which case, it looks fine.

I'll commit; thanks!

trace16 has been in there for some time; agentexpr.texi says:

@item Why does @code{trace16} exist?
That opcode was added by the customer that contracted Cygnus for the
data tracing work. I personally think it is unnecessary; objects that
large will be quite rare, so it is okay to use @code{dup const16
@var{size} trace} in those cases.

Whatever we decide to do with @code{trace16}, we should at least leave
opcode 0x30 reserved, to remain compatible with the customer who added
it.