Re: JIT compiling with LLVM v12.2

Hi,

I've pushed a revised and rebased version of my JIT patchset.
The git tree is at
  https://git.postgresql.org/git/users/andresfreund/postgres.git
in the jit branch
  https://git.postgresql.org/gitweb/?p=users/andresfreund/postgres.git;a=shortlog;h=refs/heads/jit

There's a lot of tiny changes in here:
- doc proofreading, addition of --with-llvm docs
- comments
- pgindent (jit files, not whole tree)
- syncing of order between compiled and interpreted expressions in case
  statement
- line-by-line review of expression compliation
- fix of a small memory leak (missing pfree of the JIT context struct
  itself)
- slight simplification of JIT resowner integration (no need to
  re-associate with parent)

My current plan is to push the first few commits relatively soon, give
the BF a few cycles to shake out. Set up a few BF animals with each
supported LLVM version. Then continue mergin.

Greetings,

Andres Freund