[Bug tree-optimization/106722] bogus uninit warning in tree-vect-loop-manip.cc

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106722

--- Comment #4 from CVS 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:baa3ffb19c54fa334ac2884f6acb5d31aa79ac32

commit r13-2155-gbaa3ffb19c54fa334ac2884f6acb5d31aa79ac32
Author: Richard Biener <rguenther@suse.de>
Date:   Tue Aug 23 13:58:31 2022 +0200

    tree-optimization/106722 - uninit analysis with long def -> use path

    The following applies similar measures as r13-2133-ge66cf626c72d58
    to the computation of the use predicate when the path from PHI def
    to use is too long and we run into compute_control_dep_chain limits.

    It also moves the preprocessor define limits internal.

    This resolves the reduced testcase but not the original one.

            PR tree-optimization/106722
            * gimple-predicate-analysis.h (MAX_NUM_CHAINS, MAX_CHAIN_LEN,
            MAX_POSTDOM_CHECK, MAX_SWITCH_CASES): Move ...
            * gimple-predicate-analysis.cc: ... here and document.
            (simple_control_dep_chain): New function, factored from
            predicate::use_cannot_happen.
            (predicate::use_cannot_happen): Adjust.
            (predicate::predicate): Use simple_control_dep_chain as fallback.

            * g++.dg/uninit-pr106722-1.C: New testcase.