From 69c175fe22fc876014ac7dcb7abc707be6dabb2c Mon Sep 17 00:00:00 2001 From: chriseth Date: Mon, 5 Sep 2016 15:47:21 +0200 Subject: Do not pay new account gas. If we checked that the target contract exists, we do not have to pay the "new account gas". --- Changelog.md | 1 + libsolidity/codegen/ExpressionCompiler.cpp | 4 +++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/Changelog.md b/Changelog.md index 25890890..c9de0a4b 100644 --- a/Changelog.md +++ b/Changelog.md @@ -33,6 +33,7 @@ Features: * Commandline interface: Using ``-`` as filename allows reading from stdin. * Interface Json: Fallback function is now part of the ABI. * Interface: Version string now semver compatible. + * Code generator: Do not provide "new account gas" if we know the called account exists. Bugfixes: diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp index 4a81e27d..7b6aa50a 100644 --- a/libsolidity/codegen/ExpressionCompiler.cpp +++ b/libsolidity/codegen/ExpressionCompiler.cpp @@ -1524,11 +1524,13 @@ void ExpressionCompiler::appendExternalFunctionCall( m_context << u256(0); m_context << dupInstruction(m_context.baseToCurrentStackOffset(contractStackPos)); + bool existenceChecked = false; // Check the the target contract exists (has code) for non-low-level calls. if (funKind == FunctionKind::External || funKind == FunctionKind::CallCode || funKind == FunctionKind::DelegateCall) { m_context << Instruction::DUP1 << Instruction::EXTCODESIZE << Instruction::ISZERO; m_context.appendConditionalJumpTo(m_context.errorTag()); + existenceChecked = true; } if (_functionType.gasSet()) @@ -1540,7 +1542,7 @@ void ExpressionCompiler::appendExternalFunctionCall( u256 gasNeededByCaller = eth::GasCosts::callGas + 10; if (_functionType.valueSet()) gasNeededByCaller += eth::GasCosts::callValueTransferGas; - if (!isCallCode && !isDelegateCall) + if (!isCallCode && !isDelegateCall && !existenceChecked) gasNeededByCaller += eth::GasCosts::callNewAccountGas; // we never know m_context << gasNeededByCaller << -- cgit v1.2.3