SPLASH 2021
Sun 17 - Fri 22 October 2021 Chicago, Illinois, United States
Tue 19 Oct 2021 11:20 - 11:50 at Zurich G - Session 2 Chair(s): Christophe Scholliers

On-stack replacement (OSR) is a popular technique used by just in time (JIT) compilers. A JIT can use OSR to transfer from interpreted to compiled code in the middle of execution, immediately reaping the performance benefits of compilation. This technique typically relies on loop counters, so it cannot be easily applied to languages with unstructured control flow. It is possible to reconstruct the high-level loop structures of an unstructured language using a control flow analysis, but such an analysis can be complicated, expensive, and language-specific. In this paper, we present a more lightweight strategy for OSR in unstructured languages which relies only on detecting backward jumps. We design a simple, language-agnostic API around this strategy for language interpreters. We then discuss our implementation of the API in the Truffle framework, and the design choices we made to make it efficient and correct. In our evaluation, we integrate the API with Truffle’s LLVM bitcode interpreter, and find the technique is effective at improving start-up performance without harming warmed-up performance.

Tue 19 Oct

Displayed time zone: Central Time (US & Canada) change

10:50 - 12:10
Session 2VMIL at Zurich G
Chair(s): Christophe Scholliers Universiteit Gent, Belgium
10:50
30m
Talk
A Small Scheme VM, Compiler and REPL in 4KResearch Paper
VMIL
Samuel Yvon , Marc Feeley Université de Montréal
DOI
11:20
30m
Talk
Lightweight On-Stack Replacement in Languages with Unstructured LoopsResearch Paper
VMIL
Matt D'Souza University of Waterloo, Gilles Duboscq Oracle Labs
11:50
20m
Talk
WOOD: Extending a WebAssembly VM with Out-of-Place Debugging for IoT applicationsWIP Paper
VMIL
Carlos Javier Rojas Castillo Vrije Universiteit Brussel, Matteo Marra Vrije Universiteit Brussel, Jim Bauwens Vrije Universiteit Brussel, Elisa Gonzalez Boix Vrije Universiteit Brussel
Pre-print