Chapter 2. The Mechanics of Program Execution

Now that we understand the basics of computer organization, it’s time to take a closer look at the nuts and bolts of how stored programs are actually executed by the computer. To that end, this chapter will cover core programming concepts like machine language, the programming model, the instruction set architecture, branch instructions, and the fetch-execute loop.

Opcodes and Machine Language

If you’ve been following the discussion so far, it shouldn’t surprise you to learn that both memory addresses and instructions are ordinary numbers that can be stored in memory. All of the instructions in a program like Example 1-1 are represented inside the computer as strings of numbers. Indeed, a program is ...

Get Inside the Machine now with the O’Reilly learning platform.

O’Reilly members experience live online training, plus books, videos, and digital content from nearly 200 publishers.