Also used to be in WebKit's JS engine https://webkit.org/blog/3362/introducing-the-webkit-ftl-jit/ https://webkit.org/blog/3362/introducing-the-webkit-ftl-jit/

Also used to be in WebKit's JS engine https://webkit.org/blog/3362/introducing-the-webkit-ftl-jit/ https://webkit.org/blog/3362/introducing-the-webkit-ftl-jit/ now replaced with a custom thing https://webkit.org/blog/5852/introducing-the-b3-jit-compiler/ https://webkit.org/blog/5852/introducing-the-b3-jit-compiler...