Re: JIT compiling with LLVM v9.1

Andreas Karlsson <andreas@proxel.se>

From: Andreas Karlsson <andreas@proxel.se>
To: Pierre Ducroquet <pierre.ducroquet@people-doc.com>
Cc: pgsql-hackers@lists.postgresql.org, Andres Freund <andres@anarazel.de>
Date: 2018-02-05T21:20:27Z
Lists: pgsql-hackers
OK that fixed the issue, but you have a typo in your patch set.

diff --git a/src/backend/lib/llvmjit_inline.cpp 
b/src/backend/lib/llvmjit_inline.cpp
index a785261bea..51f38e10d2 100644
--- a/src/backend/lib/llvmjit_inline.cpp
+++ b/src/backend/lib/llvmjit_inline.cpp
@@ -37,7 +37,7 @@ extern "C"
  #include <llvm/ADT/StringSet.h>
  #include <llvm/ADT/StringMap.h>
  #include <llvm/Analysis/ModuleSummaryAnalysis.h>
-#if LLVM_MAJOR_VERSION > 3
+#if LLVM_VERSION_MAJOR > 3
  #include <llvm/Bitcode/BitcodeReader.h>
  #else
  #include "llvm/Bitcode/ReaderWriter.h"

Also I get some warning. Not sure if they are from your patches or from 
Andres's.

llvmjit_error.cpp:118:1: warning: unused function 
'fatal_llvm_new_handler' [-Wunused-function]
fatal_llvm_new_handler(void *user_data,
^
1 warning generated.
llvmjit_inline.cpp:114:6: warning: no previous prototype for function 
'operator!' [-Wmissing-prototypes]
bool operator!(const llvm::ValueInfo &vi) {
      ^
1 warning generated.
psqlscanslash.l: In function ‘psql_scan_slash_option’:
psqlscanslash.l:550:8: warning: variable ‘lexresult’ set but not used 
[-Wunused-but-set-variable]
   int   final_state;
         ^~~~~~~~~

Andreas

On 02/05/2018 11:39 AM, Pierre Ducroquet wrote:
> On Sunday, February 4, 2018 12:45:50 AM CET Andreas Karlsson wrote:
>> 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
> 
> 
> I have fixed the patches, I was wrong on 'guessing' the migration of the API
> for one function.
> I have rebuilt the whole patch set. It is still based on 302b7a284d and has
> been tested with both LLVM 3.9 and 4.0 on Debian testing.
> 
> Thanks for your feedback !
> 


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".