JavaScript Engines with Mathias Bynens

JavaScript performance has improved over time due to advances in JavaScript engines such as Google’s V8. A JavaScript engine performs compiler optimization, garbage collection, hot code management, caching, and other runtime aspects that keep a JavaScript program running efficiently.  JavaScript runs in browsers and servers. The resources that are available to a JavaScript engine vary widely across different machines.

JavaScript code is parsed into an abstract tree before being handed off to the compiler toolchain, in which one or more optimizing compilers produce efficient low-level code. In recent shows about WebAssembly, we have covered compiler pipelines. In an episode about GraalVM, we explored the impact that “code shape” has on the efficiency of JavaScript execution.

Mathias Bynens is a developer advocate at Google working on the V8 JavaScript engine team. In today’s show we explore how a JavaScript engine works, and how compiler toolchains can adapt the hot code paths depending on what code needs to be optimized for.


Show Notes


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