A comprehensive, self-contained guide to assembly language — the human-readable form of the machine code a CPU actually executes.

Welcome to Assembly Language: From the Metal Up, Across Every Architecture.

A comprehensive, self-contained guide to assembly language — the human-readable form of the machine code a CPU actually executes. Above every program, no matter the language, sits a compiler or interpreter; below them all is assembly: the instructions, registers, and memory the silicon understands. This book teaches you to read and write it, to understand what your high-level code becomes, and to think the way the machine thinks. It blends intuition (what the hardware is doing and why), concepts (the architecture and the ideas behind instruction sets), and runnable code (real assembly you can assemble and run) — and it includes a multi-architecture instruction catalog (Appendices C–H) covering x86/x86-64, ARM, RISC-V, MIPS, the 6502, and more.

This title is part of the ShriIra library and is free to read in full, right here — our small contribution to making world-class knowledge easy to reach.

A note on reading it: open the Contents menu at the top of the reader to jump between chapters, use the Aa menu to set a comfortable text size, theme (light, sepia, or night), and single- or two-page layout. Your place is saved automatically, so you can always pick up where you left off.

We hope it serves you well.

— Shriira Press

Contents

1. Chapter 1 — What Is Assembly Language?
2. Chapter 2 — How Computers Execute Code: CPU, Memory, and Registers
3. Chapter 3 — Numbers, Bits, and Data Representation
4. Chapter 4 — The Toolchain: Assemblers, Linkers, and Debugging
5. Chapter 5 — Instructions and Operands: The Anatomy of Assembly
6. Chapter 6 — Data Movement and Memory Addressing
7. Chapter 7 — Arithmetic, Logic, and Bit Manipulation
8. Chapter 8 — Control Flow: Flags, Branches, Jumps, and Loops
9. Chapter 9 — The Stack, Functions, and Calling Conventions
10. Chapter 10 — Interacting with the System: Syscalls, Interrupts, and I/O
11. Chapter 11 — Assembly Across Architectures: CISC, RISC, and the Map
12. Chapter 12 — Performance, Pipelines, and SIMD
13. Chapter 13 — Assembly in Practice and the Profession
14. Appendix A — Glossary and Quick Reference
15. Appendix B — Further Reading and Resources
16. Appendix C — x86 / x86-64 Instruction Catalog
17. Appendix D — ARM Instruction Catalog (AArch64 & AArch32)
18. Appendix E — RISC-V Instruction Catalog
19. Appendix F — MIPS Instruction Catalog
20. Appendix G — 6502 Instruction Catalog
21. Appendix H — Other Architectures: Z80, AVR, PowerPC, SPARC