Here it is formated nicly:

*$ = sub{
    $a=q;}die;;
    sub u{
        $_;
    }
    $= && unpack u => u;
};
s[]{82G5S="!A;F]T:&5R(%!E<FP\@:&%C:V5R}six;
die &$ => $/;
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Boiled down this can be represented by

*$=sub{
    unpack "u", $_;
};
$_='82G5S="!A;F]T:&5R(%!E<FP@:&%C:V5R';
die &$, $/;
[download]

or even a one-liner:

die unpack ("u", '82G5S="!A;F]T:&5R(%!E<FP@:&%C:V5R'), $/;
[download]

With this, you should be able to figure out what was done to hide the code.