Section 3: Memory, Addressing, and Data Manipulation

Section 3 Summary

This section covers the intricacies of memory addressing, data representation, and how assembly code manipulates data. You will learn different addressing modes, how endianness affects interpretation, and how alignment matters in low-level code.

Lesson 3.1: Addressing Modes in x86-64

Learning Objectives

  • Identify and use various addressing modes (register indirect, base+index, etc.).
  • Analyze how addressing modes translate into final memory addresses.

Prerequisites

  • Basic assembly syntax.
  • Familiarity with register usage for memory addressing.
Key Concepts
  • Register Indirect: mov rax, [rbx]
  • Base + Displacement: mov rax, [rbx+8]
  • Base + Index * Scale + Displacement: mov rax, [rbx + rcx*4 + 16]

Detailed Explanation

x86-64 Addressing Formula

The general formula for x86-64 memory addressing is:

Effective Address = Base + Index * Scale + Displacement

Where:
- Base: Any general-purpose register (optional)
- Index: Any general-purpose register except RSP (optional)  
- Scale: 1, 2, 4, or 8 (only when Index is used)
- Displacement: Signed 8-bit or 32-bit offset (optional)

Additional content would continue here with detailed examples, exercises, and explanations...

Recommended Resources

🚧 Section In Progress

Section 3 is being restructured to match the original crash course specification. The complete lessons will include:

  • Lesson 3.1: Addressing Modes in x86-64
  • Lesson 3.2: Reading and Writing Data
  • Lesson 3.3: Moving Data Between Registers and Memory
  • Lesson 3.4: Endianness and Data Representation
  • Lesson 3.5: Alignments and Structs in Assembly

Each lesson will include detailed explanations, practical examples, exercises, and real-world applications.