This is a new version of https://github.com/ocaml-flambda/flambda-backend/pull/2677 using the double region variable and ghost region approach. This seems to work pretty well, not least because it's shown up two concepts that I think were previously being conflated: these can be seen now as Alloc_mode.For_applications.t and Alloc_mode.For_allocations.t.
This is a new version of https://github.com/ocaml-flambda/flambda-backend/pull/2677 using the double region variable and ghost region approach. This seems to work pretty well, not least because it's shown up two concepts that I think were previously being conflated: these can be seen now as
Alloc_mode.For_applications.tandAlloc_mode.For_allocations.t.