Re: JIT compiling with LLVM v9.0

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>
To: Andres Freund <andres@anarazel.de>
Cc: Jeff Davis <pgsql@j-davis.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2018-01-30T18:46:37Z
Lists: pgsql-hackers
On Mon, Jan 29, 2018 at 1:40 PM, Andres Freund <andres@anarazel.de> wrote:
> It's an optional dependency, and it doesn't increase build time that
> much... If we were to move the llvm interfacing code to a .so, there'd
> not even be a packaging issue, you can just package that .so separately
> and get errors if somebody tries to enable LLVM without that .so being
> installed.

I suspect that would be really valuable.  If 'yum install
postgresql-server' (or your favorite equivalent) sucks down all of
LLVM, some people are going to complain, either because they are
trying to build little tiny machine images or because they are subject
to policies which preclude the presence of a compiler on a production
server.  If you can do 'yum install postgresql-server' without
additional dependencies and 'yum install postgresql-server-jit' to
make it go faster, that issue is solved.

Unfortunately, that has the pretty significant downside that a lot of
people who actually want the postgresql-server-jit package will not
realize that they need to install it, which sucks.  But I think it
might still be the better way to go.  Anyway, it's for individual
packagers to cope with that problem; as far as the patch goes, +1 for
structuring things in a way which gives packagers the option to divide
it up that way.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


Commits

  1. Improve JIT docs.

  2. Add documentation for the JIT feature.

  3. Add EXPLAIN support for JIT.

  4. Add inlining support to LLVM JIT provider.

  5. JIT tuple deforming in LLVM JIT provider.

  6. Add FIELDNO_* macro designating offset into structs required for JIT.

  7. Add expression compilation support to LLVM JIT provider.

  8. Expand list of synchronized types and functions in LLVM JIT provider.

  9. Add helpers for emitting LLVM IR.

  10. Basic planner and executor integration for JIT.

  11. Debugging and profiling support for LLVM JIT provider.

  12. Support for optimizing and emitting code in LLVM JIT provider.

  13. Add file containing extensions of the LLVM C API.

  14. Basic JIT provider and error handling infrastructure.

  15. Add configure infrastructure (--with-llvm) to enable LLVM support.

  16. Add C++ support to configure.

  17. Add PGAC_PROG_VARCC_VARFLAGS_OPT autoconf macro.

  18. Fix VM buffer pin management in heap_lock_updated_tuple_rec().

  19. Allow tupleslots to have a fixed tupledesc, use in executor nodes.

  20. Expression evaluation based aggregate transition invocation.

  21. Perform slot validity checks in a separate pass over expression.

  22. Rely on executor utils to build targetlist for DML RETURNING.

  23. Refer to OS X as "macOS", except for the port name which is still "darwin".