Horton

Re: JIT compiling with LLVM v9.1

Andreas Karlsson <andreas@proxel.se>

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From: Andreas Karlsson <andreas@proxel.se>
To: Pierre Ducroquet <p.psql@pinaraf.info>, pgsql-hackers@lists.postgresql.org
Cc: Andres Freund <andres@anarazel.de>
Date: 2018-02-03T23:45:50Z
Lists: pgsql-hackers 
On 02/02/2018 10:48 AM, Pierre Ducroquet wrote:
> I have successfully built the JIT branch against LLVM 4.0.1 on Debian testing.
> This is not enough for Debian stable (LLVM 3.9 is the latest available there),
> but it's a first step.
> I've split the patch in four files. The first three fix the build issues, the
> last one fixes a runtime issue.
> I think they are small enough to not be a burden for you in your developments.
> But if you don't want to carry these ifdefs right now, I maintain them in a
> branch on a personal git and rebase as frequently as I can.

I tested these patches and while the code built for me and passed the 
test suite on Debian testing I have a weird bug where the very first 
query fails to JIT while the rest work as they should. I think I need to 
dig into LLVM's codebase to see what it is, but can you reproduce this 
bug at your machine?

Code to reproduce:

SET jit_expressions = true;
SET jit_above_cost = 0;
SELECT 1;
SELECT 1;

Output:

postgres=# SELECT 1;
ERROR:  failed to jit module
postgres=# SELECT 1;
  ?column?
----------
         1
(1 row)

Config:

Version: You patches applied on top of 
302b7a284d30fb0e00eb5f0163aa933d4d9bea10
OS: Debian testing
llvm/clang: 4.0.1-8

Andreas

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".