Function count_nonzero_u32

numpy/core/src/multiarray/item_selection.c:2524–2552

}

static inline NPY_GCC_OPT_3 npy_intp
count_nonzero_u32(const char *data, npy_intp bstride, npy_uintp len)
{
    npy_intp count = 0;
#if NPY_SIMD
    if (bstride == sizeof(npy_uint32)) {
        const npy_uintp max_iter = NPY_MAX_UINT32*npyv_nlanes_u32;
        const npy_uintp len_m = (len > max_iter ? max_iter : len) & -npyv_nlanes_u32;
        const npyv_u32 vone   = npyv_setall_u32(1);
        const npyv_u32 vzero  = npyv_zero_u32();

        npyv_u32 vsum32 = npyv_zero_u32();
        for (const char *end = data + len_m*bstride; data < end; data += NPY_SIMD_WIDTH) {
            npyv_u32 mask = npyv_cvt_u32_b32(npyv_cmpeq_u32(npyv_load_u32((npy_uint32*)data), vzero));
                     mask = npyv_and_u32(mask, vone);
                   vsum32 = npyv_add_u32(vsum32, mask);
        }
        const npyv_u32 maskevn = npyv_reinterpret_u32_u64(npyv_setall_u64(0xffffffffULL));
        npyv_u64 odd  = npyv_shri_u64(npyv_reinterpret_u64_u32(vsum32), 32);
        npyv_u64 even = npyv_reinterpret_u64_u32(npyv_and_u32(vsum32, maskevn));
        count = len_m - npyv_sum_u64(npyv_add_u64(odd, even));
        len  -= len_m;
    }
#endif
    for (; len > 0; --len, data += bstride) {
        count += (*(npy_uint32*)data != 0);
    }
    return count;
}

static inline NPY_GCC_OPT_3 npy_intp
count_nonzero_u64(const char *data, npy_intp bstride, npy_uintp len)