[Bug tree-optimization/112310] [14 Regression] Wrong code at -O2/3 on x86_64-linux-gnu since r14-1161-g5476de2618f

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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112310

--- 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:2266f7cbc78dfcf7c0739466644e0a6b9966553c

commit r14-5095-g2266f7cbc78dfcf7c0739466644e0a6b9966553c
Author: Richard Biener <rguenther@suse.de>
Date:   Fri Nov 3 10:45:18 2023 +0100

    tree-optimization/112310 - code hoisting undefined behavior

    The following avoids hoisting expressions that may invoke undefined
    behavior and are not computed on all paths.  This is realized by
    noting that we have to avoid materializing expressions as part
    of hoisting that are not part of the set of expressions we have
    found eligible for hoisting.  Instead of picking the expression
    corresponding to the hoistable values from the first successor
    we now keep a union of the expressions so that hoisting can pick
    the expression that has its dependences fully hoistable.

            PR tree-optimization/112310
            * tree-ssa-pre.cc (do_hoist_insertion): Keep the union
            of expressions, validate dependences are contained within
            the hoistable set before hoisting.

            * gcc.dg/torture/pr112310.c: New testcase.