#define silc_atomic_sub_int16(a, v) silc_atomic_add_int16(a, (-v))
#define silc_atomic_sub_int32(a, v) silc_atomic_add_int32(a, (-v))
#define silc_atomic_sub_int16(a, v) silc_atomic_add_int16(a, (-v))
#define silc_atomic_sub_int32(a, v) silc_atomic_add_int32(a, (-v))