You're only going to some limited benefit by tweaking the regex patterns. Shaving 20% off of 60 seconds is still 48 seconds.

One thing I see is that you're scanning the file from to to bottom for each s/// operator, and often more than once per pattern. Your efforts might be better spent avoid that. Some examples are self contained, 

while ($contents =~ s/\05([^\n\05]+)\05/$1\05\05/gs) {}

   |
   |
   v

$contents =~ s/\05([^\n\05]+)(?=\05)/$1\05/gs;

[download]

But that's not going to help you remove this waste in general.

In reply to Re: tight loop regex optimization by ikegami
in thread tight loop regex optimization by superawesome

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