[Bug tree-optimization/122297] Wrong code due to bad VEC_EXTRACT index when LEN_LOAD falls back to QI mode

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122297

--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Juergen Christ <jchr...@gcc.gnu.org>:

https://gcc.gnu.org/g:2291c5c4471040acd3da83b5e2cbe56d7b4720e9

commit r16-7435-g2291c5c4471040acd3da83b5e2cbe56d7b4720e9
Author: Juergen Christ <jchr...@linux.ibm.com>
Date:   Thu Feb 5 11:42:45 2026 +0100

    tree-optimization/122297 - fix load/store bias handling

    When load/store with length is used and only QImode versions are
    available, vectorizable_live_operation produces wrong results for
    VEC_EXTRACT.  Provide a flag to vect_get_loop_len to specify if
    bias-adjusted length should be used or not.

    gcc/ChangeLog:

            PR tree-optimization/122297
            * tree-vect-loop.cc (vectorize_fold_left_reduction): Adjust.
            (vectorizable_induction): Adjust.
            (vectorizable_live_operation_1): Adjust.
            (vect_get_loop_len): Provide parameter to select bias-adjusted
            length.
            (vect_gen_loop_len_mask): Adjust.
            (vect_update_ivs_after_vectorizer_for_early_breaks): Adjust.
            * tree-vect-stmts.cc (vect_get_strided_load_store_ops): Adjust.
            (vectorizable_call): Adjust.
            (vectorizable_operation): Adjust.
            (vectorizable_store): Adjust.
            (vectorizable_load): Adjust.
            (vectorizable_condition): Adjust.
            * tree-vectorizer.h (vect_get_loop_len): Add parameter.

    gcc/testsuite/ChangeLog:

            PR tree-optimization/122297
            * gcc.dg/vect/nodump-extractlast-1.c: Fix typo.
            * gcc.dg/vect/nodump-extractlast-2.c: New test.

    Signed-off-by: Juergen Christ <jchr...@linux.ibm.com>