Write Great Code.Vol.2

INTRODUCTION

There are many aspects of great code far too many to describe properly in a single book. Therefore, this second volume of the Write Great Code series concentrates on one important part of great code: performance. As computer systems have increased in performance from MHz, to hundreds of MHz, to GHz, the performance of computer software has taken a back seat to other concerns. Today, it is not at all uncommon for software engineers to exclaim, You should never optimize your code! Funny, you don t hear too many computer application users making such statements.

Although this book describes how to write efficient code, it is not a book about optimization. Optimization is a phase near the end of the software development cycle in which software engineers determine why their code does not meet performance specifications and then massage the code to achieve those specifications. But unfortunately, if no thought is put into the performance of the application until the optimization phase, it s unlikely that optimization will prove practical. The time to ensure that an application has reasonable performance characteristics is at the beginning, during the design and implementation phases. Optimization can fine-tune the performance of a system, but it can rarely deliver a miracle.

Although the quote is often attributed to Donald Knuth, who popularized it, it was Tony Hoare who originally said, Premature optimization is the root of all evil. This statement has long been the rallying cry of software engineers who avoid any thought of application performance until the very end of the software-development cycle at which point the optimization phase is typically ignored for economic or time-to-market reasons. However, Hoare did not say, Concern about application performance during the early stages of an application s development is the root of all evil. He specifically said premature optimization, which, back then, meant counting cycles and

Introduction

Chapter 1: Thinking Low-Level, Writing High-Level
Chapter 2: Shouldn't You Learn Assembly Language?
Chapter 3: 80x86 Assembly for the HLL Programmer
Chapter 4: Compiler Operation and Code Generation
Chapter 5: Tools for Analyzing Compiler Output
Chapter 6: Constants and High-Level Languages
Chapter 7: Variables in a High-Level Language
Chapter 8: Array Data Types
Chapter 9: Pointer Data Types
Chapter 10: String Data Types
Chapter 11: Record, Union, and Class Data Types
Chapter 12: Arithmetic and Logical Expressions
Chapter 13: Control Structures and Programmatic Decisions
Chapter 14: Iterative Control Structures
Chapter 15: Functions and Procedures

Afterword: Engineering Software
Glossary

Randall Hyde

Praise for the first edition of Write Great Code, Volume 2:

"Set aside some money and buy this book, or get a friend to buy it and get it from them while still in the store. When you get home, read it TWICE so that you master what is in these pages. Then read it again."
DevCity

"Write Great Code Volume 2 exceeds its goal of helping developers pay more attention to application performance when writing applications in high-level languages. This book is a must for any high-level application developer.
Free Software Magazine

"As a high-level-language programmer, if you want to know what's really going on with your programs, you need to spend a little time learning assembly language and you won't find an easier introduction."
DevX

"This is a good book. A very very good book. Frankly, I'm blown away at the quality of writing."
Toronto Ruby User Group