I recently r-ewatched a 1993 documentary about the South African police flying squad in Soweto in the last days of apartheid, in which one officer stated that if facing a hostile crowd brandishing anything other than firearms, they were suppose to shoot for the legs in the first instance. Whether they actual did might be another question, but that was what their guidelines were.
In relation to swords there was the similar case in the UK of Simon Murden, who - under the influence of drugs and sleep deprivation - drove his van the wrong way up a dual carriageway and eventually crashed. Armed police arrived on the scene, and when Murden was 14 metres from them, he brandished an African sword. He was shot twice with baton rounds (plastic bullets) to no effect. Another officer then shot Murden twice using a Heckler & Koch MP5 semi-automatic carbine. When Murden did not react, he shot him twice more, which caused him collapse to his knees. When he got up again, the officer fired twice more, and Murden collapsed to the ground. Officers claimed that he appeared to try to get up, whilst pointing the sword in their direction. He was shot three more time. At this point he was still 9 metres away from the officers. A coroner ruled it justifiable homicide, but to me it seems that under the circumstances only the first four live rounds were fully justified. Just because he got to his feet after that doesn't mean he was in a position to immediately harm anyone, given the distance between himself and the officers. This is even more pertinent with shots 7-9, when he was on the ground and merely pointing the sword at the officers.