Replace assert with KOKKOS_ASSERT in kernel code

[masterleinad]

Fixes #949.

[aprokop]

Might as well also remove the <cassert> header inclusion in files that don't use assert.

[aprokop]

Would be nice if kokkos/kokkos#5403 was resolved first to not bring Kokkos_Core.hpp.

[dalg24]

Why is it acceptable to pull in the full <Kokkos_Core.hpp> header?
What are the pros and cons as compared to rolling our own?

[masterleinad]

Why is it acceptable to pull in the full <Kokkos_Core.hpp> header? What are the pros and cons as compared to rolling our own?

My two cents:

• Effectively, any code that uses ArborX needs Kokkos_Core.hpp anyway since that's what you need for a parallel_for or for using View anyway as of now. It's realistic to make the needed Kokkos header public pretty soon and transitioning is very easy since it only means to change an include.
• It seems that KOKKOS_ASSERT is doing what we want and so coming up with our own solution/macro would probably be pretty much a copy of what Kokkos provides already. If we roll or own, potentially moving to KOKKOS_ASSERT when we only need the Kokkos_Error.hpp (or whatever it will be called) header requires more changes than using it from the beginning.

[dalg24]

(Not saying we must define our own but disagreeing with the comment above) Purging the unnecessary header includes is more difficult than search and replace.

[aprokop]

Should we create ArborX_KokkosExtAssert.hpp to hide the complexity?

[dalg24]

Did you consider including impl/Kokkos_Error.hpp instead? I suspect that would work.

[masterleinad]

Cons:

• impl/Kokkos_Error.hpp is not a public header. We shouldn't be a bad example.
• up to Kokkos version 4.2.0 (at the very least), there is not much of a chance for an ArborX executable to be able to include less than Kokkos_Core.hpp anyway.

Pros:

• we only include non-public headers up to a version that we know the file exists.
• we don't rely on Kokkos_Core.hpp including headers we should provide ourselves, see Include <iostream> when using it in examples and benchmaks #956, before version 4.2.0.

[dalg24]

Cons:

• impl/Kokkos_Error.hpp is not a public header. We shouldn't be a bad example.

In our implementation details only. I don't think that is an issue.

• up to Kokkos version 4.2.0 (at the very least), there is not much of a chance for an ArborX executable to be able to include less than Kokkos_Core.hpp anyway.

I don't understand the point you want to make.

[masterleinad]

Retest this please.

[aprokop]

HIP did not start, one CUDA build ran out of disk space. Otherwise, good.