[PATCH bpf-next v2 1/6] bpf: Introduce 64-bit bitops kfuncs

[Alexei Starovoitov]

On Thu, Feb 19, 2026 at 6:30 AM Leon Hwang <leon.hwang at linux.dev> wrote:
>
>
> +static bool bpf_kfunc_is_fastcall(struct bpf_verifier_env *env, u32 func_id, u32 flags)
> +{
> +       if (!(flags & KF_FASTCALL))
> +               return false;
> +
> +       if (!env->prog->jit_requested)
> +               return true;
> +
> +       if (func_id == special_kfunc_list[KF_bpf_clz64])
> +               return bpf_jit_inlines_kfunc_call(bpf_clz64);
> +       if (func_id == special_kfunc_list[KF_bpf_ctz64])
> +               return bpf_jit_inlines_kfunc_call(bpf_ctz64);
> +       if (func_id == special_kfunc_list[KF_bpf_ffs64])
> +               return bpf_jit_inlines_kfunc_call(bpf_ffs64);
> +       if (func_id == special_kfunc_list[KF_bpf_fls64])
> +               return bpf_jit_inlines_kfunc_call(bpf_fls64);
> +       if (func_id == special_kfunc_list[KF_bpf_bitrev64])
> +               return bpf_jit_inlines_kfunc_call(bpf_bitrev64);
> +       if (func_id == special_kfunc_list[KF_bpf_popcnt64])
> +               return bpf_jit_inlines_kfunc_call(bpf_popcnt64);
> +       if (func_id == special_kfunc_list[KF_bpf_rol64])
> +               return bpf_jit_inlines_kfunc_call(bpf_rol64);
> +       if (func_id == special_kfunc_list[KF_bpf_ror64])
> +               return bpf_jit_inlines_kfunc_call(bpf_ror64);

This is too ugly. Find a way to do it differently.