4. Assembly Language & Computer Architecture

TL;DR

Assembly language and computer architecture are important for writing fast code and understanding how a computer works at a low level.

Transcript

The following content is provided under a Creative Commons license. Your support will help MIT OpenCourseWare continue to offer high quality educational resources for free. To make a donation or to view additional materials from hundreds of MIT courses, visit MIT OpenCourseWare at ocw.mit.edu. CHARLES LEISERSON: So today, we're going to talk about ... Read More

Key Insights

• 👋 Assembly language is the best interface for understanding and optimizing the performance of a computer program.
• 🍻 Compilation involves multiple stages, including preprocessing, compiling, assembling, and linking.
• 👀 Looking at assembly code can reveal what the compiler did and did not do, help identify bugs, and enable reverse engineering.

Questions & Answers

Q: Why is it important to look at the assembly code of a program?

Looking at the assembly code can help understand how the compiler optimizes your code and identify any performance issues or compiler bugs. It can also help you write faster code by exploiting the strengths of the architecture.

Q: What are some reasons to use assembly language?

Assembly language can be used to write code that needs to be highly optimized, interfacing with low-level hardware, reverse engineering, and understanding how a program works at a low level.

Q: How does the preprocessing stage of compilation work?

The preprocessing stage involves running the preprocessor, which expands macros and includes header files, among other things. You can invoke the preprocessor manually with the clang -e command to see how your code is expanded before compilation.

Summary & Key Takeaways

• Assembly language is the best interface to understand the inner workings of computer architecture and write fast code.

• Compilation involves several stages, including preprocessing, compiling, assembling, and linking.

• Assembly code is a human-readable version of machine code that can be generated using compilers like Clang.