This chapter discusses "pure" assembly language control statements. You'll need to master these low-level control structures before you can claim to be an assembly language programmer. By the time you finish this chapter, you should be able to stop using HLA's high-level control statements and synthesize them using low-level 80x86 machine instructions.
The last section of this chapter discusses hybrid control structures that combine the features of HLA's high-level control statements with the 80x86 control instructions. These combine the power and efficiency of the low-level control statements with the readability of high-level control statements. Advanced assembly programmers may want to use these hybrid statements to improve their programs' readability without sacrificing efficiency.
Until now, most of the control structures you've seen and have used in your programs are similar to the control structures found in high-level languages like Pascal, C++, and Ada. While these control structures make learning assembly language easy, they are not true assembly language statements. Instead, the HLA compiler translates these control structures into a sequence of "pure" machine instructions that achieve the same result as the high-level control structures. This text uses the high-level control structures to allow you to learn assembly language without having to learn everything all at once. Now, however, it's time to put aside these high-level control structures and learn how to write your programs in real assembly language, using low-level control structures.