UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

A study of inline assembly in solidity smart contracts

Chaliasos, S; Gervais, A; Livshits, B; (2022) A study of inline assembly in solidity smart contracts. Proceedings of the ACM on Programming Languages , 6 (OOPSLA2) , Article 165. 10.1145/3563328. Green open access

[thumbnail of oopsla22.pdf]
Preview
PDF
oopsla22.pdf - Other

Download (836kB) | Preview

Abstract

The Solidity programming language is the most widely used language for smart contract development. Improving smart contracts' correctness, security, and performance has been the driving force for research in vulnerability detection, program analysis, and compiler techniques for Solidity. Similar to system-level languages such as C, Solidity enables the embedding of low-level code in programs, in the form of inline assembly code. Developers use inline assembly for low-level optimizations, extending the Solidity language through libraries, and using blockchain-specific opcodes only available through inline assembly. Nevertheless, inline assembly fragments are not well understood by an average developer and can introduce security threats as well as affect the optimizations that can be applied to programs by the compiler; it also significantly limits the effectiveness of source code static analyzers that operate on the Solidity level. A better understanding of how inline assembly is used in practice could in turn increase the performance, security, and support for inline assembly in Solidity. This paper presents a large-scale quantitative study of the use of inline assembly in 6.8M smart contracts deployed on the Ethereum blockchain. We find that 23% of the analyzed smart contracts contain inline assembly code, and that the use of inline assembly has become more widespread over time. We further performed a manual qualitative analysis for identifying usage patterns of inline assembly in Solidity smart contracts. Our findings are intended to help practitioners understand when they should use inline assembly and guide developers of Solidity tools in prioritizing which parts of inline assembly to implement first. Finally, the insights of this study could be used to enhance the Solidity language, improve the Solidity compiler, and to open up new research directions by driving future researchers to build appropriate methods and techniques for replacing inline assembly in Solidity programs when there is no real necessity to use it.

Type: Article
Title: A study of inline assembly in solidity smart contracts
Open access status: An open access version is available from UCL Discovery
DOI: 10.1145/3563328
Publisher version: https://doi.org/10.1145/3563328
Language: English
Additional information: This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions.
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Computer Science
URI: https://discovery.ucl.ac.uk/id/eprint/10182353
Downloads since deposit
20Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item