Execution models

[Dan Heidinga]

Hi, partly inspired by Anton's "Provide arguments for restore" PR [1],
I wrote up some thoughts on how we can use those changes to make our
source code phase-aware.

The key takeaway in my post [2] is that being able to specify one main
class for the checkpoint phase and another for the restore phase lets
developers reflect the structure of these phases in their source code.
That's powerful!

Something to be thinking about as we evolve our approach to checkpoint/restore.

--Dan

[1] https://github.com/openjdk/crac/pull/16
[2] https://danheidinga.github.io/phase-aware-source-code/