I think it's worth noting that both perl -MO=Concise -e 'do {next unless $x}' and perl -MO=Concise -e 'do {$x||next}' produce exactly the same output (at least on v5.26):

9  <@> leave[1 ref] vKP/REFC ->(end)
1     <0> enter ->2
2     <;> nextstate(main 1 -e:1) v:{ ->3
-     <1> null vK*/1 ->9
8        <@> leave vKP ->9
3           <0> enter v ->4
4           <;> nextstate(main 2 -e:1) v:{ ->5
-           <1> null vK/1 ->8
6              <|> or(other->7) vK/1 ->8
-                 <1> ex-rv2sv sK/1 ->6
5                    <$> gvsv(*x) s ->6
7                 <0> next v* ->8
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See the last four lines in particular. If there's no difference in the ops, then B::Deparse, which "generates perl source code based on the internal compiled structure", probably won't be able to tell the difference either.

Minor edits.