Abstract
We present the main concepts, components, and usage of Gasol, a Gas AnalysiS and Optimization tooL for Ethereum smart contracts. Gasol offers a wide variety of cost models that allow inferring the gas consumption associated to selected types of EVM instructions and/or inferring the number of times that such types of bytecode instructions are executed. Among others, we have cost models to measure only storage opcodes, to measure a selected family of gas-consumption opcodes following the Ethereum’s classification, to estimate the cost of a selected program line, etc. After choosing the desired cost model and the function of interest, Gasol returns to the user an upper bound of the cost for this function. As the gas consumption is often dominated by the instructions that access the storage, Gasol uses the gas analysis to detect under-optimized storage patterns, and includes an (optional) automatic optimization of the selected function. Our tool can be used within an Eclipse plugin for Solidity which displays the gas and instructions bounds and, when applicable, the gas-optimized Solidity function.
Footnotes
This work was funded partially by the Spanish MCIU, AEI and FEDER (EU) projects RTI2018-094403-B-C31 and RTI2018-094403-B-C33, the MINECO and FEDER (EU) projects TIN2015-69175-C4-2-R and TIN2015-69175-C4-3-R, by the CM projects P2018/TCS-4314 and S2018/TCS-4339 co-funded by EIE Funds of the EU and by the UCM CT27/16-CT28/16 grant.
The software and dataset used during the current study are available at 10.6084/m9.figshare.11876697.
Contributor Information
Armin Biere, Email: biere@jku.at.
David Parker, Email: d.a.parker@cs.bham.ac.uk.
Pablo Gordillo, Email: pabgordi@ucm.es.
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