If you trust the input to contain nothing evil, eval will do: 
$s = "(1 << 18) | (0x00 << 12) | (0x00 << 6) | 0x00";
printf "0x%x\n", eval $s;

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In reply to Re: Convert bitwise value to its value by mbethke
in thread Convert bitwise value to its value by gibsonca

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