Computers as Components, 2nd Edition

5.10 Program Validation and Testing 267

language coding of key program segments. There may also be cases in which one

or a sequence of instructions is much smaller than alternative implementations—

for example, a multiply-accumulate instruction may be both smaller and faster than

separate arithmetic operations.

When reducing the number of instructions in a program, one important tech-

nique is the proper use of subroutines. If the program performs identical operations

repeatedly, these operations are natural candidates for subroutines. Even if the

operations vary somewhat, you may be able to construct a properly parameter-

ized subroutine that saves ...