Horton

Re: JIT compiling with LLVM v12.2

Thomas Munro <thomas.munro@enterprisedb.com>

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From: Thomas Munro <thomas.munro@enterprisedb.com>
To: Andres Freund <andres@anarazel.de>
Cc: Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2018-03-21T02:22:08Z
Lists: pgsql-hackers 
On Wed, Mar 21, 2018 at 1:50 PM, Andres Freund <andres@anarazel.de> wrote:
> On 2018-03-20 03:14:55 -0700, Andres Freund wrote:
>> My current plan is to push the first few commits relatively soon, give
>> the BF a few cycles to shake out. Set up a few BF animals with each
>> supported LLVM version. Then continue mergin.
>
> I've done that.  I'll set up a number of BF animals as soon as I've got
> the buildfarm secrets for them.

Somehow your configure test correctly concludes that my $CC (clang
4.0) doesn't support -fexcess-precision=standard but that my $CXX
(clang++ 4.0) does, despite producing a nearly identical warning:

configure:5489: checking whether ccache cc supports
-fexcess-precision=standard, for CFLAGS
configure:5511: ccache cc -c -Wall -Wmissing-prototypes
-Wpointer-arith -Wdeclaration-after-statement -Wendif-labels
-Wmissing-format-attribute -Wformat-security -fno-strict-aliasing
-fwrapv -fexcess-precision=standard  conftest.c >&5
cc: warning: optimization flag '-fexcess-precision=standard' is not
supported [-Wignored-optimization-argument]
configure:5511: $? = 0
configure: failed program was:
...
configure:5521: result: no

configure:5528: checking whether ccache c++ supports
-fexcess-precision=standard, for CXXFLAGS
configure:5556: ccache c++ -c -Wall -Wpointer-arith
-fno-strict-aliasing -fwrapv -fexcess-precision=standard  conftest.cpp
>&5
c++: warning: optimization flag '-fexcess-precision=standard' is not
supported [-Wignored-optimization-argument]
configure:5556: $? = 0
configure:5572: result: yes

So it goes into my $CXXFLAGS and then I get the same warning when
compiling the three .cpp files in the tree.

GCC also doesn't like that in C++ mode, but it seems to report an
error (rather than a warning) so with g++ as your $CXX configure sees
$? = 1 and draws the correct conclusion.

$ gcc -fexcess-precision=standard -c test.c
$ g++ -fexcess-precision=standard -c test.cpp
cc1plus: sorry, unimplemented: -fexcess-precision=standard for C++

-- 
Thomas Munro
http://www.enterprisedb.com

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".