DeepAI AI Chat
Log In Sign Up

Supporting On-Stack Replacement in Unstructured Languages by Loop Reconstruction and Extraction

by   Raphael Mosaner, et al.
Johannes Kepler University Linz
ETH Zurich

On-stack replacement (OSR) is a common technique employed by dynamic compilers to reduce program warm-up time. OSR allows switching from interpreted to compiled code during the execution of this code. The main targets are long running loops, which need to be represented explicitly, with dedicated information about condition and body, to be optimized at run time. Bytecode interpreters, however, represent control flow implicitly via unstructured jumps and thus do not exhibit the required high-level loop representation. To enable OSR also for jump-based - often called unstructured - languages, we propose the partial reconstruction of loops in order to explicitly represent them in a bytecode interpreter. Besides an outline of the general idea, we implemented our approach in Sulong, a bytecode interpreter for LLVM bitcode, which allows the execution of C/C++. We conducted an evaluation with a set of C benchmarks, which showed speed-ups in warm-up of up to 9x for certain benchmarks. This facilitates execution of programs with long-running loops in rarely called functions, which would yield significant slowdown without OSR. While shown with a prototype implementation, the overall idea of our approach is generalizable for all bytecode interpreters.


page 10

page 11


Analyzing Smart Contracts: From EVM to a sound Control-Flow Graph

The EVM language is a simple stack-based language with words of 256 bits...

On-Stack Replacement à la Carte

On-stack replacement (OSR) dynamically transfers execution between diffe...

Deoptless: Speculation with Dispatched On-Stack Replacement and Specialized Continuations

Just-in-time compilation provides significant performance improvements f...

Tamarin: Concolic Disequivalence for MIPS

Given two MIPS programs, when are they equivalent? At first glance, this...

Putting in All the Stops: Execution Control for JavaScript

Scores of compilers produce JavaScript, enabling programmers to use many...

Eye: Program Visualizer for CS2

In recent years, programming has witnessed a shift towards using standar...

Hybrid Static/Dynamic Schedules for Tiled Polyhedral Programs

Polyhedral compilers perform optimizations such as tiling and paralleliz...