Comment (by Erik Schnetter):

enter_local_mode is generally called from the scheduler, in CallFunction, when the driver knows which scheduled function is going to be called.

enter_global_mode is usually called further outwards when a scheduled function is not known. We could change that, so that it is only called for particular scheduled functions. This would be straightforward in CarpetX, probably less so in Carpet.

I would worry about Driver_RequireValidData at the moment, as this is probably a function that is very rarely called. If we can set up a special case that speeds up thorns that don’t call this function I’d be very happy already. For example, such thorns could call CCTK_VarDataPtr instead of looking into the cGH structure.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2512/enable-detection-of-attribute-pure