Horton

Re: Improving and extending int128.h to more of numeric.c

Dean Rasheed <dean.a.rasheed@gmail.com>

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From: Dean Rasheed <dean.a.rasheed@gmail.com>
To: John Naylor <johncnaylorls@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2025-07-09T09:38:31Z
Lists: pgsql-hackers 
On Wed, 9 Jul 2025 at 07:41, John Naylor <johncnaylorls@gmail.com> wrote:
>
> Hi Dean, I went to take a look at this and got stuck at building the
> test file. The usual pointing gcc to the src and build include
> directories didn't cut it. How did you get it to work?
>

Yes, it wasn't immediately obvious how to do it. I first built
postgres as normal, including the  pg_config tool, and then used that
to compile the test as follows:

gcc -O3 -g \
    src/tools/testint128.c \
    -I$(pg_config --includedir-server) \
    -o src/tools/testint128 \
    $(pg_config --libs)

It actually only needs -lpgcommon -lpgport -lm, but it seemed easier
just to include all of the pg_config --libs.

Regards,
Dean

Commits

  1. Guard against division by zero in test_int128 module.

  2. Extend int128.h to support more numeric code.

  3. Simplify non-native 64x64-bit multiplication in int128.h.

  4. Optimise non-native 128-bit addition in int128.h.

  5. Refactor int128.h, bringing the native and non-native code together.

  6. Convert src/tools/testint128.c into a test module.