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Re: Tracepoint enhancements

Stan Shebs wrote:
Michael Snyder wrote:
[...] a checkpoint
represents a machine state.  If there are multiple machines,
that complicates the picture -- but basically gdb is saying
to the target "I want to be able to return to the state that
you are in *right now*".
Hmm, that is a significant wrinkle to the execution history theory. Basically it's not possible to know reliably whether the execution state of one CPU comes sooner or later than the state of another CPU - their clocks can't be guaranteed to be sync'ed to a sub-instruction level. It's a little like a distributed version control system, where each repository has its own version numbers, and any ordering derives from explicit push/pull instructions. Each inferior can have a reliable execution history, but if you want to go back to state X on CPU 1, you either just affect the one inferior, or expect that other inferiors will go back to the closest available state in their histories.

All true. I think this sub-branch of the discussion was mostly blue-sky.

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