Remove useless stuff

Hey,

I think I found some useless code thanks to Mladen. In engine_count_and_link_tasks_mapper, we should only have gravity and hydro-density task. Therefore there is no point of dealing with the other type of tasks.

I have been able to run the EAGLE_6 example at low redshift and with the full physics for ~100 steps without any problem.

added cleanup code health labels

Thanks. I'll have a look. Was your test over MPI?

Yes 2 ranks

By the way, I think we do not need this structure anymore: https://gitlab.cosma.dur.ac.uk/swift/swiftsim/-/blob/master/src/task.h#L144

I agree with your analysis of what happens in the engine. I'll put the MR on the back burner though as I am working on changes touching some of the code around there separately. And since this is non-blocking, we can wait a bit to merge this.

Thanks both for spotting this!

merged

mentioned in commit c7303413