[Bug middle-end/112406] [14 Regression] Several SPECCPU 2017 benchmarks fail with on internal compiler error: in expand_insn, at optabs.cc:8305 after g:01c18f58d37865d5f3bbe93e666183b54ec608c7

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112406

--- Comment #22 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Robin Dapp <rdapp@gcc.gnu.org>:

https://gcc.gnu.org/g:2bbc7f4ef6329df62146fd6d0da5f30750cc72b4

commit r14-5697-g2bbc7f4ef6329df62146fd6d0da5f30750cc72b4
Author: Robin Dapp <rdapp@ventanamicro.com>
Date:   Tue Nov 21 12:51:12 2023 +0100

    vect: Allow reduc_index != 1 for COND_OPs.

    In PR112406 Tamar found another problem with COND_OP reductions.
    I wrongly assumed that the reduction variable will always remain in
    operand 1, just as we create the COND_OP in ifcvt.  But of course,
    addition being commutative, we are free to swap operand 1 and 2 and we
    end up with e.g.

     _ifc__60 = .COND_ADD (_2, _6, MADPictureC1_lsm.10_25,
MADPictureC1_lsm.10_25);

    which does not pass the asserts I put in place.

    This patch removes this restriction and allows the reduction index to be
    2 as well.

    gcc/ChangeLog:

            PR middle-end/112406

            * tree-vect-loop.cc (vectorize_fold_left_reduction): Allow
            reduction index != 1.
            (vect_transform_reduction): Handle reduction index != 1.

    gcc/testsuite/ChangeLog:

            * gcc.target/aarch64/pr112406-2.c: New test.