Write Great Code, Volume 2

Chapter 15. Iterative Control Structures

Most programs spend the majority of their time executing program instructions within a loop. Therefore, if you want to improve the execution speed of your applications, you should first look to see if you can improve the performance of the loops that execute in your code. In this chapter, I’ll describe the following varieties of loops:

• while loops

• repeat..until/do..while loops

• forever (infinite) loops

• for (definite) loops

15.1 The while Loop

The while loop is, perhaps, the most general-purpose iterative statement that HLLs provide. For this reason, compilers generally work hard at emitting optimal code for while ...