Read Writeup Formatting Tips and edit your post using "code" tags around your text file contents. We can't tell how many lines are in your file. This should get you started: 
use warnings;
use strict;

while (<DATA>) {
    if (/(\w+)=\w+ (\w+)=/) {
        my $diff = hex($2) - hex($1);
        printf "0x%x %d\n", $diff, $diff;
    }
}

__DATA__
0x405d75=inst1 0x405d7a=inst2

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In reply to Re: Subtract 2 hexadecimal numbers by toolic
in thread Subtract 2 hexadecimal numbers by samd

Title:
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