[Bug tree-optimization/113734] [14 regression] libarchive miscompiled (fails libarchive_test_read_format_rar5_extra_field_version test) since r14-8768-g85094e2aa6dba7

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113734

--- Comment #27 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tamar Christina <tnfchris@gcc.gnu.org>:

https://gcc.gnu.org/g:491e57451df47cda88f658601a92d6d006ae09d7

commit r14-8952-g491e57451df47cda88f658601a92d6d006ae09d7
Author: Tamar Christina <tamar.christina@arm.com>
Date:   Tue Feb 13 11:04:38 2024 +0000

    middle-end: update vector loop upper bounds when early break vect
[PR113734]

    When doing early break vectorization we should treat the final iteration as
    possibly being partial.  This so that when we calculate the vector loop
upper
    bounds we take into account that final iteration could have done some work.

    The attached testcase shows that if we don't then cunroll may unroll the
loop an
    if the upper bound is wrong we lose a vector iteration.

    This is similar to how we adjust the scalar loop bounds for the PEELED
case.

    gcc/ChangeLog:

            PR tree-optimization/113734
            * tree-vect-loop.cc (vect_transform_loop): Treat the final
iteration of
            an early break loop as partial.

    gcc/testsuite/ChangeLog:

            PR tree-optimization/113734
            * gcc.dg/vect/vect-early-break_117-pr113734.c: New test.