A shortened form of "would have (been)". Another — dialectical — variation of this is "had'a".

It's a hypothetical conditional as opposed to 'had been'
—Somewhat prevalent in Australia. And it's also used in Britain, and some parts of the U.S.
Would've; Had'a; Hadn'a; Had've
Had it have been different, people often wouldn't be such petty assholes
by Abbie Snyder May 29, 2022
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