[Bug tree-optimization/114203] [13/14 Regression] Miscompilation: A possible miscompilation in GCC 13 and 14 with option -Os

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114203

--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:cde50296a19b109909089b91d532d2c8455f5f10

commit r14-9293-gcde50296a19b109909089b91d532d2c8455f5f10
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Mar 4 10:38:31 2024 +0100

    tree-optimization/114203 - wrong CLZ niter computation

    For precision less than int we apply the adjustment to make it defined
    at zero after the adjustment to make it compute CLZ rather than CTZ.
    That's wrong.

            PR tree-optimization/114203
            * tree-ssa-loop-niter.cc (build_cltz_expr): Apply CTZ->CLZ
            adjustment before making the result defined at zero.

            * gcc.dg/torture/pr114203.c: New testcase.