Avoid computation for debug output when not in debug mode
Avoid computation for debug output when not in debug mode

Reviewed By: mroch

Differential Revision: D40373969

fbshipit-source-id: d607cffce590b6191d40b1d74762ca655e9388d2

mroch/flow,mroch/flow,mroch/flow,facebook/flow,facebook/flow,mroch/flow,facebook/flow,mroch/flow,facebook/flow,facebook/flow,mroch/flow,mroch/flow,facebook/flow,facebook/flow