The HipHop Virtual Machine

ACM International Conference on Object Oriented Programming Systems, Languages, and Applications


The HipHop Virtual Machine (HHVM) is a JIT compiler and runtime for PHP. While PHP values are dynamically typed, real programs often have latent types that are useful for optimization once discovered. Some types can be proven through static analysis, but limitations in the ahead-of-time approach leave some types to be discovered at run time. And even though many values have latent types, PHP programs can also contain polymorphic variables and expressions, which must be handled without catastrophic slowdown.

HHVM discovers latent types by structuring its JIT around the concept of a tracelet. A tracelet is approximately a basic block specialized for a particular set of run-time types for its input values. Tracelets allow HHVM to exactly and efficiently learn the types observed by the program, while using a simple compiler. This paper shows that this approach enables HHVM to achieve high levels of performance, without sacrificing compatibility or interactivity.

Related Publications

All Publications

11-Gbps Broadband Modem-Agnostic Line-of-Sight MIMO Over the Range of 13 km

Yan Yan, Pratheep Bondalapati, Abhishek Tiwari, Chiyun Xia, Andy Cashion, Dawei Zhang, Tobias Tiecke, Qi Tang, Michael Reed, Dudi Shmueli, Hongyu Zhou, Bob Proctor, Joseph Stewart

IEEE GLOBECOM - January 21, 2019

Deep Learning Training in Facebook Data Centers: Design of Scale-up and Scale-out Systems

Maxim Naumov, John Kim, Dheevatsa Mudigere, Srinivas Sridharan, Xiaodong Wang, Whitney Zhao, Serhat Yilmaz, Changkyu Kim, Hector Yuen, Mustafa Ozdal, Krishnakumar Nair, Isabel Gao, Bor-Yiing Su, Jiyan Yang, Mikhail Smelyanskiy

arXiv - September 3, 2020

PyTorch Distributed: Experiences on Accelerating Data Parallel Training

Shen Li, Yanli Zhao, Rohan Verma, Omkar Salpekar, Pieter Noordhuis, Teng Li, Adam Paszke, Jeff Smith, Brian Vaughan, Pritam Damania, Soumith Chintala

VLDB - August 31, 2020

MyRocks: LSM-Tree Database Storage Engine Serving Facebook’s Social Graph

Yoshinori Matsunobu, Siying Dong, Herman Lee

VLDB - August 31, 2020

To help personalize content, tailor and measure ads, and provide a safer experience, we use cookies. By clicking or navigating the site, you agree to allow our collection of information on and off Facebook through cookies. Learn more, including about available controls: Cookies Policy