Bare Metal JavaScript: The JavaScript Virtual Machine

Ever wondered how high-level JavaScript turns into low-level CPU instructions? Learn the fundamentals of CPU mechanics to see how code runs through memory operations, inline caching, and deoptimization. You'll build a mental model of JavaScript's performance characteristics by learning how virtual machines (like Google's V8 engine) work under the hood!

This course and others like it are available as part of our Frontend Masters video subscription.

Table of Contents:

Introduction

• Introduction

How the CPU Runs Code

• Physical & Virtual Machines
• CPU Basics & Speed Limits
• CPU Memory Management
• CPU Subroutines & Calling Conventions
• CPU Q&A
• Fibonacci

Virtual Machine Inlining & Deopt

• Optimizing Code
• Deopt Explorer & Fixing a Deopt
• Object Shapes & Hidden Classes

Micro Benchmarking

• Object Shapes & Inline Caching
• Inspecting Inline Caches with Deopt Explorer
• Double & Triple Equals
• Object & Array Copying
• Negative Numbers
• Holey Arrays
• Amdahl’s Law

Wrapping Up

• Wrapping Up