Green’s Dictionary of Slang

whup v.

also whoop
[SE whip]
[20C+] (US)

1. to make someone suffer, i.e. to beat fig.

2. to attack, to beat up; also attrib.; thus whupping n.

3. to defeat, e.g. in a competition.

4. to punch.

In compounds

whup-a-child (n.)

[1970s+] (US black) the police, a police officer.

In phrases

whup the game (v.) [game n. (6)]

[1970s+] (US black) to succeed in life.