Computers as Components, 2nd Edition

266 CHAPTER 5 Program Design and Analysis

Metha et al. [Met97] present some additional observations about energy

optimization as follows:

■ Moderate loop unrolling eliminates some loop control overhead. However,

when the loop is unrolled too much, power increases due to the lower hit

rates of straight-line code.

■ Software pipelining reduces pipeline stalls, thereby reducing the average

energy per instruction.

■ Eliminating recursive procedure calls where possible saves power by getting

rid of function call overhead. Tail recursion can often be eliminated; some

compilers do this automatically.

5.9 ANALYSIS AND OPTIMIZATION OF PROGRAM SIZE

The memory footprint ...