Re: JIT compiling with LLVM v9.0

Andres Freund <andres@anarazel.de>

From: Andres Freund <andres@anarazel.de>
To: Pierre Ducroquet <p.psql@pinaraf.info>
Cc: pgsql-hackers@lists.postgresql.org
Date: 2018-01-25T19:12:42Z
Lists: pgsql-hackers
Hi,

On 2018-01-25 10:00:14 +0100, Pierre Ducroquet wrote:
> I don't know when this would be released,

August-October range.


> but the minimal supported LLVM 
> version will have a strong influence on the availability of that feature. If 
> today this JIT compiling was released with only LLVM 5/6 support, it would be 
> unusable for most Debian users (llvm-5 is only available in sid). Even llvm 4 
> is not available in latest stable.
> I'm already trying to build with llvm-4 and I'm going to try further with llvm 
> 3.9 (Debian Stretch doesn't have a more recent than this one, and I won't have 
> something better to play with my data), I'll keep you informed. For sport, I 
> may also try llvm 3.5 (for Debian Jessie).

I don't think it's unreasonable to not support super old llvm
versions. This is a complex feature, and will take some time to
mature. Supporting too many LLVM versions at the outset will have some
cost.  Versions before 3.8 would require supporting mcjit rather than
orc, and I don't think that'd be worth doing.  I think 3.9 might be a
reasonable baseline...

Greetings,

Andres Freund


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".