I think this is good as far as it goes, but I would assume that the OP wants to XOR some humongous things that cannot be represented as simple Perl numeric scalar values? In this case, use hex() function. 
my $x = "aabbcc"; 
my $y = "112233";

printf '%x', hex($x) ^ hex($y); #bb99ff

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This causes integer overflow if $x and $y are "too big".

In reply to Re^2: Hex String XOR by Marshall
in thread Hex String XOR by alanonymous

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