book

Write Great Code, Volume 2, 2nd Edition

by Randall Hyde

August 2020

Intermediate to advanced

656 pages

16h 15m

English

No Starch Press

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Performance Characteristics of Great CodeThe Goal of This BookChapter OrganizationAssumptions and PrerequisitesThe Environment for This BookFor More Information
1.1 Misconceptions About Compiler Quality1.2 Why Learning Assembly Language Is Still a Good Idea1.3 Why Learning Assembly Language Isn’t Absolutely Necessary1.4 Thinking Low-Level1.5 Writing High-Level1.6 Language-Neutral Approach1.7 Additional Tips1.8 For More Information
2.1 Benefits and Roadblocks to Learning Assembly Language2.2 How This Book Can Help2.3 High-Level Assemblers to the Rescue2.4 High-Level Assembly Language2.5 Thinking High-Level, Writing Low-Level2.6 The Assembly Programming Paradigm (Thinking Low-Level)2.7 For More Information

3.1 Learning One Assembly Language Is Good, Learning More Is Better3.2 80x86 Assembly Syntaxes3.3 Literal Constants3.4 Manifest (Symbolic) Constants in Assembly Language3.5 80x86 Addressing Modes3.6 Declaring Data in Assembly Language3.7 Specifying Operand Sizes in Assembly Language3.8 For More Information
4.1 File Types That Programming Languages Use4.2 Source Files4.3 Types of Computer Language Processors4.4 The Translation Process4.5 Compiler Output4.6 Object File Formats4.7 Executable File Formats4.8 Data and Code Alignment in an Object File4.9 How Linkers Affect Code4.10 For More Information
5.1 Background5.2 Telling a Compiler to Produce Assembly Output5.3 Using Object Code Utilities to Analyze Compiler Output5.4 Using a Disassembler to Analyze Compiler Output5.5 Using the Java Bytecode Disassembler to Analyze Java Output5.6 Using the IL Disassembler to Analyze Microsoft C# and Visual Basic Output5.7 Using a Debugger to Analyze Compiler Output5.8 Comparing Output from Two Compilations5.9 For More Information
6.1 Literal Constants and Program Efficiency6.2 Binding Times6.3 Literal Constants vs. Manifest Constants6.4 Constant Expressions6.5 Manifest Constants vs. Read-Only Memory Objects6.6 Swift let Statements6.7 Enumerated Types6.8 Boolean Constants6.9 Floating-Point Constants6.10 String Constants6.11 Composite Data Type Constants6.12 Constants Don’t Change6.13 For More Information
7.1 Runtime Memory Organization7.2 What Is a Variable?7.3 Variable Storage7.4 Common Primitive Data Types7.5 Variable Addresses and High-Level Languages7.6 Variable Alignment in Memory7.7 For More Information
8.1 Arrays8.2 For More Information
9.1 The Definition of a Pointer9.2 Pointer Implementation in High-Level Languages9.3 Pointers and Dynamic Memory Allocation9.4 Pointer Operations and Pointer Arithmetic9.5 A Simple Memory Allocator Example9.6 Garbage Collection9.7 The OS and Memory Allocation9.8 Heap Memory Overhead9.9 Common Pointer Problems9.10 Pointers in Modern Languages9.11 Managed Pointers9.12 For More Information
10.1 Character String Formats10.2 Static, Pseudo-Dynamic, and Dynamic Strings10.3 Reference Counting for Strings10.4 Delphi Strings10.5 Using Strings in a High-Level Language10.6 Unicode Character Data in Strings10.7 Unicode String Functions and Performance10.8 For More Information
11.1 Records11.2 Discriminant Unions11.3 Variant Types11.4 Namespaces11.5 Classes and Objects11.6 Protocols and Interfaces11.7 Classes, Objects, and Performance11.8 For More Information
12.1 Arithmetic Expressions and Computer Architecture12.2 Optimization of Arithmetic Statements12.3 Side Effects in Arithmetic Expressions12.4 Containing Side Effects: Sequence Points12.5 Avoiding Problems Caused by Side Effects12.6 Forcing a Particular Order of Evaluation12.7 Short-Circuit Evaluation12.8 The Relative Cost of Arithmetic Operations12.9 For More Information
13.1 How Control Structures Affect a Program’s Efficiency13.2 Introduction to Low-Level Control Structures13.3 The goto Statement13.4 The if Statement13.5 The switch/case Statement13.6 For More Information
14.1 The while Loop14.2 The repeat..until (do..until/do..while) Loop14.3 The forever..endfor Loop14.4 The Definite Loop (for Loops)14.5 For More Information
15.1 Simple Function and Procedure Calls15.2 Leaf Functions and Procedures15.3 Macros and Inline Functions15.4 Passing Parameters to a Function or Procedure15.5 Activation Records and the Stack15.6 Parameter-Passing Mechanisms15.7 Function Return Values15.8 For More Information

Content preview from Write Great Code, Volume 2, 2nd Edition

14ITERATIVE CONTROL STRUCTURES

Most programs spend the majority of their time executing machine instructions within a loop. Therefore, if you want to improve your applications’ execution speed, first you should see if you can improve the performance of the loops in your code. This chapter will describe the following varieties of loops:

while loops
repeat..until/do..while loops
forever (infinite) loops
for (definite) loops

14.1 The while Loop

The while loop is perhaps the most general-purpose iterative statement that HLLs provide, so compilers generally work hard at emitting optimal code for it. The while loop tests a Boolean expression at the ...