This change moves almost everything in the `upb/` directory up one level, so
that for example `upb/upb/generated_code_support.h` becomes just
`upb/generated_code_support.h`. The only exceptions I made to this were that I
left `upb/cmake` and `upb/BUILD` where they are, mostly because that avoids
conflict with other files and the current locations seem reasonable for now.
The `python/` directory is a little bit of a challenge because we had to merge
the existing directory there with `upb/python/`. I made `upb/python/BUILD` into
the BUILD file for the merged directory, and it effectively loads the contents
of the other BUILD file via `python/build_targets.bzl`, but I plan to clean
this up soon.
PiperOrigin-RevId: 568651768
This is the second attempt to fix our Git history. This should allow
"git blame" to work correctly in the upb/ directory even though our
automation unexpectedly blew away that directory.
It ended up being odd to construct the AccessorGenerators ahead of time given some specific Context<>: since each of the three methods on AccessorGenerators demands a different Context than the initial one so they shouldn't hold that Context anyway. It ended up just being a spooky parallel array to the Fields with an unenforced invariant that all methods would be called with a new Context<> but the same underlying FieldDescriptor later.
PiperOrigin-RevId: 558770643
This CL sets up the basic plumbing end-to-end for singular message fields.
We add skeletonized support for `Proxied` messages. This is done
by creating structs for $Msg$View and $Msg$Mut, and providing
stubbed impls.
PiperOrigin-RevId: 552609955
The intent of this change is to take the best ideas from the C++ backend, such as having generator objects that can cache pre-computed state, while minimizing duplication.
Where possible, we take the approach of making the C++ and UPB kernel-specific code as similar as possible, since this reduces the number of templates we need to keep in sync.
PiperOrigin-RevId: 524903073