You can't have a dynamical number of captures in Perl 5, which is why you either need split or a regex with the /g modifier in a while loop.

There are hacks, though:

$_ = "abc*def*ghi";

my @matches;
m/(?: ([^*]+) (?{ push @matches, $^N}) \*?)+/x;

print join('|', @matches), $/;
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But before you use this, read the big fat warning in perlre about how experimental (?{ ... }) is.