[Bug middle-end/118994] GCC fails to optimize (a >> 1) + (b >> 1) + ((a | b) & 1) to PAVGB/PAVGW (or equivalent instruction)

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118994

--- Comment #8 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by hongtao Liu <liuho...@gcc.gnu.org>:

https://gcc.gnu.org/g:72f0b446d2c03866ebe4cae125e32fef598e924d

commit r16-767-g72f0b446d2c03866ebe4cae125e32fef598e924d
Author: liuhongt <hongtao....@intel.com>
Date:   Tue Feb 25 22:48:27 2025 -0800

    Add pattern match in match.pd for .AVG_CEIL

    1) Optimize (a >> 1) + (b >> 1) + ((a | b) & 1) to .AVG_CEIL (a, b)
    2) Optimize (a | b) - ((a ^ b) >> 1) to .AVG_CEIL (a, b)

    gcc/ChangeLog:

            PR middle-end/118994
            * match.pd ((a >> 1) + (b >> 1) + ((a | b) & 1) to
            .AVG_CEIL (a, b)): New pattern.
            ((a | b) - ((a ^ b) >> 1) to .AVG_CEIL (a, b)): Ditto.

    gcc/testsuite/ChangeLog:

            * gcc.target/i386/pr118994-1.c: New test.
            * gcc.target/i386/pr118994-2.c: New test.