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Re: Tracepoint enhancements

Michael Snyder wrote:
Vladimir Prus wrote:
Michael Snyder wrote:

One more thing, only vaguely related...

I've thought that if we had the ability to attach an expression
(in pcode such as we use for tracepoints) to a conditional breakpoint,
we could have the conditional evaluation be done on the target
rather than by gdb, which would be a big performance win for
conditional breakpoints or watchpoints.

Yes. We want conditional tracepoints, and the condition would have to be evaluated
on the target. And if breakpoints and tracepoints are unified, both breakpoints and
tracepoints will benefit.

Very good point. OK, you've convinced me.
I shall proceed on the assumption that we will make a tracepoint a kind of breakpoint. This means we no longer need the special enable/disable/delete commands. I think the original "trace" command should remain as-is, and I'm also inclined to leave "actions" alone for the moment, rather than try to merge with "commands"; while there could be some useful unification, it seems like more of a sweeping change to try to decide for every command, whether it could be part of a tracepoint action or not. We get tracepoint conditions via "condition" and "trace ... if" then. Not clear if "info tracepoints" should stick around as a subset of "info breakpoints".

Ignore counts vs passcounts still mystify me a bit. They seem conceptually similar (modulo the sense inversion), but the documentation for passcounts makes it seems as though one might expect all tracing and all tracepoints to be disabled once a passcount is exceeded for any one of them - and I see where that might be the desired behavior, vs the per-breakpoint control of ignore counts.


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