[Bug tree-optimization/118976] [12 Regression] Correctness Issue: SVE vectorization results in data corruption when cpu has 128bit vectors but compiled with -mcpu=neoverse-v1 (which is only for 256bit vector cpus)

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118976

--- Comment #22 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Richard Sandiford
<rsandifo@gcc.gnu.org>:

https://gcc.gnu.org/g:587b370c8492aadaab14c57e242c66778cc78891

commit r12-10987-g587b370c8492aadaab14c57e242c66778cc78891
Author: Richard Sandiford <richard.sandiford@arm.com>
Date:   Tue Mar 11 15:51:55 2025 +0000

    Fix folding of BIT_NOT_EXPR for POLY_INT_CST [PR118976]

    There was an embarrassing typo in the folding of BIT_NOT_EXPR for
    POLY_INT_CSTs: it used - rather than ~ on the poly_int.  Not sure
    how that happened, but it might have been due to the way that
    ~x is implemented as -1 - x internally.

    gcc/
            PR tree-optimization/118976
            * fold-const.cc (const_unop): Use ~ rather than - for BIT_NOT_EXPR.
            * config/aarch64/aarch64.cc (aarch64_test_sve_folding): New
function.
            (aarch64_run_selftests): Run it.

    (cherry picked from commit 78380fd7f743e23dfdf013d68a2f0347e1511550)