[Bug tree-optimization/123311] Min(clz(a), clz(b))->clz(a|b) likewise for ctz

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123311

--- Comment #1 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Eikansh Gupta <eikansh@gcc.gnu.org>:

https://gcc.gnu.org/g:1743c12e3512bff3c9688dff7bba5b2ac43cd9d5

commit r17-2815-g1743c12e3512bff3c9688dff7bba5b2ac43cd9d5
Author: Eikansh Gupta <eikansh.gupta@oss.qualcomm.com>
Date:   Tue May 19 12:20:54 2026 +0530

    MATCH: Simplify min of clz/ctz to clz/ctz of bitwise or [PR123311]

    This adds match.pd simplifications for min(clz(x), clz(y)) and
    min(ctz(x), ctz(y)) to clz(x | y) and ctz(x | y).

    Bootstrapped and tested on aarch64-linux-gnu and x86_64-linux-gnu.

            PR tree-optimization/123311

    gcc/ChangeLog:

            * match.pd (min(clz(x), clz(y)) -> clz(x | y)): New pattern.
            (min(ctz(x), ctz(y)) -> ctz(x | y)): Likewise.

    gcc/testsuite/ChangeLog:

            * gcc.dg/tree-ssa/pr123311-1.c: New test.
            * gcc.dg/tree-ssa/pr123311-2.c: New test.

    Signed-off-by: Eikansh Gupta <eikansh.gupta@oss.qualcomm.com>