Are you sure? AFAIK the prediction will usually assume that the called address will be the same as the last one, so in an inner loop (eg. mapping a function ove

Are you sure? AFAIK the prediction will usually assume that the called address will be the same as the last one, so in an inner loop (eg. mapping a function over an array), only the first call would take a long time, and then only by 20-25 cycles. If a loop is so tight that 5 or so cycles per iteration matters, there shouldn't be a function call in it in the first place. (I've googled earlier and someone measured a virtual call in a tight loop to take about twice the time of a direct one. Intel doc says a call is about 5 cycles. That would mean an extra 5 cycles or so for the indirection.)