[Bug target/118141] GCC miscompiles __builtin_convertvector() narrowing operation on amd64 above -O1

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118141

--- Comment #8 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
    for (int i = 0; i < 8; i++) {
        input_vec[i] = std::bit_cast<unsigned int>(((float*) input)[i]);
    }


Is how to handle it for C++20.


    for (int i = 0; i < 8; i++) {
        memcpy(&input_vec[i], &((unsigned int*) input)[i], sizeof(unsigned
int));
    }

Is how you use memcpy.