From 928ce088456987431143262dcde2d02553b68192 Mon Sep 17 00:00:00 2001 From: chriseth Date: Wed, 11 Apr 2018 18:30:20 +0200 Subject: [PATCH] Correctly ignore costs of fallback for other functions. --- Changelog.md | 1 + libsolidity/interface/GasEstimator.cpp | 9 ++++++++- test/libsolidity/GasMeter.cpp | 13 +++++++++++++ 3 files changed, 22 insertions(+), 1 deletion(-) diff --git a/Changelog.md b/Changelog.md index 6df11f275..c6de5872e 100644 --- a/Changelog.md +++ b/Changelog.md @@ -27,6 +27,7 @@ Bugfixes: * Code Generator: Treat empty base constructor argument list as not provided. * Commandline interface: Support ``--evm-version constantinople`` properly. * DocString Parser: Fix error message for empty descriptions. + * Gas Estimator: Correctly ignore costs of fallback function for other functions. * Standard JSON: Support ``constantinople`` as ``evmVersion`` properly. * Type Checker: Fix detection of recursive structs. * Type Checker: Fix asymmetry bug when comparing with literal numbers. diff --git a/libsolidity/interface/GasEstimator.cpp b/libsolidity/interface/GasEstimator.cpp index 2139395f2..a496cc21e 100644 --- a/libsolidity/interface/GasEstimator.cpp +++ b/libsolidity/interface/GasEstimator.cpp @@ -136,12 +136,19 @@ GasEstimator::GasConsumption GasEstimator::functionalEstimation( ExpressionClasses& classes = state->expressionClasses(); using Id = ExpressionClasses::Id; using Ids = vector; + // div(calldataload(0), 1 << 224) equals to hashValue Id hashValue = classes.find(u256(FixedHash<4>::Arith(FixedHash<4>(dev::keccak256(_signature))))); Id calldata = classes.find(Instruction::CALLDATALOAD, Ids{classes.find(u256(0))}); classes.forceEqual(hashValue, Instruction::DIV, Ids{ calldata, - classes.find(u256(1) << (8 * 28)) + classes.find(u256(1) << 224) }); + // lt(calldatasize(), 4) equals to 0 (ignore the shortcut for fallback functions) + classes.forceEqual( + classes.find(u256(0)), + Instruction::LT, + Ids{classes.find(Instruction::CALLDATASIZE), classes.find(u256(4))} + ); } PathGasMeter meter(_items, m_evmVersion); diff --git a/test/libsolidity/GasMeter.cpp b/test/libsolidity/GasMeter.cpp index fd2017f92..0d66456ce 100644 --- a/test/libsolidity/GasMeter.cpp +++ b/test/libsolidity/GasMeter.cpp @@ -294,6 +294,19 @@ BOOST_AUTO_TEST_CASE(extcodesize_gas) testRunTimeGas("f()", vector{encodeArgs()}); } +BOOST_AUTO_TEST_CASE(regular_functions_exclude_fallback) +{ + // A bug in the estimator caused the costs for a specific function + // to always include the costs for the fallback. + char const* sourceCode = R"( + contract A { + uint public x; + function() { x = 2; } + } + )"; + testCreationTimeGas(sourceCode); + testRunTimeGas("x()", vector{encodeArgs()}); +} BOOST_AUTO_TEST_SUITE_END() }