[Bug target/124903] [LoopVectorize][AArch64] GCC fails to vectorize strided reduction with type conversion that Clang vectorizes with NEON

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124903

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Blocks|                            |53947

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
On x86-64 with AVX512 we can vectorize the simplified

short foo(
    const float * __restrict__ a,
    int n
) {
    long product = 1;
    for (int i = 0; i < n; i ++)
    {
        product *= (long)a[(i)];
    }
    return (short)product;
}


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53947
[Bug 53947] [meta-bug] vectorizer missed-optimizations