Horton

Re: JIT compiling with LLVM v9.0

Pierre Ducroquet <p.psql@pinaraf.info>

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From: Pierre Ducroquet <p.psql@pinaraf.info>
To: Andres Freund <andres@anarazel.de>
Cc: pgsql-hackers@lists.postgresql.org
Date: 2018-01-28T22:02:56Z
Lists: pgsql-hackers 
On Thursday, January 25, 2018 8:12:42 PM CET Andres Freund wrote:
> 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

Hi

I have fixed the build issues with LLVM 3.9 and 4.0. The LLVM documentation is 
really lacking when it comes to porting from version x to x+1.
The only really missing part I found is that in 3.9, GlobalValueSummary has no 
flag showing if it's not EligibleToImport. I am not sure about the 
consequences.
I'm still fixing some runtime issues so I will not bother you with the patch 
right now.
BTW, the makefile for src/backend/lib does not remove the llvmjit_types.bc 
file when cleaning, and doesn't seem to install in the right folder.

Regards

	Pierre

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".