Upset -- and in pieces?

I believe the answer is:

cut up

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'upset' is the definition.
Both the definition and answer are adjectives. Maybe there's a link between them I don't understand?

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for cut up that I've seen before include "Badly hurt" , "affected by separation" , "Distressed - dissected" , "Sliced; distressed" , "Deeply distressed (slang)" .)

I've seen this clue in The Telegraph.

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