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Diffstat (limited to 'libsolidity/inlineasm/AsmAnalysis.cpp')
| -rw-r--r-- | libsolidity/inlineasm/AsmAnalysis.cpp | 630 |
1 files changed, 0 insertions, 630 deletions
diff --git a/libsolidity/inlineasm/AsmAnalysis.cpp b/libsolidity/inlineasm/AsmAnalysis.cpp deleted file mode 100644 index ac019c06..00000000 --- a/libsolidity/inlineasm/AsmAnalysis.cpp +++ /dev/null @@ -1,630 +0,0 @@ -/* - This file is part of solidity. - - solidity is free software: you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation, either version 3 of the License, or - (at your option) any later version. - - solidity is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with solidity. If not, see <http://www.gnu.org/licenses/>. -*/ -/** - * Analyzer part of inline assembly. - */ - -#include <libsolidity/inlineasm/AsmAnalysis.h> - -#include <libsolidity/inlineasm/AsmData.h> -#include <libsolidity/inlineasm/AsmScopeFiller.h> -#include <libsolidity/inlineasm/AsmScope.h> -#include <libsolidity/inlineasm/AsmAnalysisInfo.h> - -#include <libsolidity/interface/ErrorReporter.h> - -#include <boost/range/adaptor/reversed.hpp> -#include <boost/algorithm/string.hpp> - -#include <memory> -#include <functional> - -using namespace std; -using namespace dev; -using namespace dev::solidity; -using namespace dev::solidity::assembly; - -namespace { - -set<string> const builtinTypes{"bool", "u8", "s8", "u32", "s32", "u64", "s64", "u128", "s128", "u256", "s256"}; - -} - -bool AsmAnalyzer::analyze(Block const& _block) -{ - if (!(ScopeFiller(m_info, m_errorReporter))(_block)) - return false; - - return (*this)(_block); -} - -bool AsmAnalyzer::operator()(Label const& _label) -{ - solAssert(!_label.name.empty(), ""); - checkLooseFeature( - _label.location, - "The use of labels is disallowed. Please use \"if\", \"switch\", \"for\" or function calls instead." - ); - m_info.stackHeightInfo[&_label] = m_stackHeight; - warnOnInstructions(solidity::Instruction::JUMPDEST, _label.location); - return true; -} - -bool AsmAnalyzer::operator()(assembly::Instruction const& _instruction) -{ - checkLooseFeature( - _instruction.location, - "The use of non-functional instructions is disallowed. Please use functional notation instead." - ); - auto const& info = instructionInfo(_instruction.instruction); - m_stackHeight += info.ret - info.args; - m_info.stackHeightInfo[&_instruction] = m_stackHeight; - warnOnInstructions(_instruction.instruction, _instruction.location); - return true; -} - -bool AsmAnalyzer::operator()(assembly::Literal const& _literal) -{ - expectValidType(_literal.type.str(), _literal.location); - ++m_stackHeight; - if (_literal.kind == assembly::LiteralKind::String && _literal.value.str().size() > 32) - { - m_errorReporter.typeError( - _literal.location, - "String literal too long (" + to_string(_literal.value.str().size()) + " > 32)" - ); - return false; - } - else if (_literal.kind == assembly::LiteralKind::Number && bigint(_literal.value.str()) > u256(-1)) - { - m_errorReporter.typeError( - _literal.location, - "Number literal too large (> 256 bits)" - ); - return false; - } - else if (_literal.kind == assembly::LiteralKind::Boolean) - { - solAssert(m_flavour == AsmFlavour::Yul, ""); - solAssert(_literal.value == YulString{string("true")} || _literal.value == YulString{string("false")}, ""); - } - m_info.stackHeightInfo[&_literal] = m_stackHeight; - return true; -} - -bool AsmAnalyzer::operator()(assembly::Identifier const& _identifier) -{ - solAssert(!_identifier.name.empty(), ""); - size_t numErrorsBefore = m_errorReporter.errors().size(); - bool success = true; - if (m_currentScope->lookup(_identifier.name, Scope::Visitor( - [&](Scope::Variable const& _var) - { - if (!m_activeVariables.count(&_var)) - { - m_errorReporter.declarationError( - _identifier.location, - "Variable " + _identifier.name.str() + " used before it was declared." - ); - success = false; - } - ++m_stackHeight; - }, - [&](Scope::Label const&) - { - ++m_stackHeight; - }, - [&](Scope::Function const&) - { - m_errorReporter.typeError( - _identifier.location, - "Function " + _identifier.name.str() + " used without being called." - ); - success = false; - } - ))) - { - } - else - { - size_t stackSize(-1); - if (m_resolver) - { - bool insideFunction = m_currentScope->insideFunction(); - stackSize = m_resolver(_identifier, yul::IdentifierContext::RValue, insideFunction); - } - if (stackSize == size_t(-1)) - { - // Only add an error message if the callback did not do it. - if (numErrorsBefore == m_errorReporter.errors().size()) - m_errorReporter.declarationError(_identifier.location, "Identifier not found."); - success = false; - } - m_stackHeight += stackSize == size_t(-1) ? 1 : stackSize; - } - m_info.stackHeightInfo[&_identifier] = m_stackHeight; - return success; -} - -bool AsmAnalyzer::operator()(FunctionalInstruction const& _instr) -{ - solAssert(m_flavour != AsmFlavour::Yul, ""); - bool success = true; - for (auto const& arg: _instr.arguments | boost::adaptors::reversed) - if (!expectExpression(arg)) - success = false; - // Parser already checks that the number of arguments is correct. - auto const& info = instructionInfo(_instr.instruction); - solAssert(info.args == int(_instr.arguments.size()), ""); - m_stackHeight += info.ret - info.args; - m_info.stackHeightInfo[&_instr] = m_stackHeight; - warnOnInstructions(_instr.instruction, _instr.location); - return success; -} - -bool AsmAnalyzer::operator()(assembly::ExpressionStatement const& _statement) -{ - int initialStackHeight = m_stackHeight; - bool success = boost::apply_visitor(*this, _statement.expression); - if (m_stackHeight != initialStackHeight && (m_flavour != AsmFlavour::Loose || m_errorTypeForLoose)) - { - Error::Type errorType = m_flavour == AsmFlavour::Loose ? *m_errorTypeForLoose : Error::Type::TypeError; - string msg = - "Top-level expressions are not supposed to return values (this expression returns " + - to_string(m_stackHeight - initialStackHeight) + - " value" + - (m_stackHeight - initialStackHeight == 1 ? "" : "s") + - "). Use ``pop()`` or assign them."; - m_errorReporter.error(errorType, _statement.location, msg); - if (errorType != Error::Type::Warning) - success = false; - } - m_info.stackHeightInfo[&_statement] = m_stackHeight; - return success; -} - -bool AsmAnalyzer::operator()(assembly::StackAssignment const& _assignment) -{ - checkLooseFeature( - _assignment.location, - "The use of stack assignment is disallowed. Please use assignment in functional notation instead." - ); - bool success = checkAssignment(_assignment.variableName, size_t(-1)); - m_info.stackHeightInfo[&_assignment] = m_stackHeight; - return success; -} - -bool AsmAnalyzer::operator()(assembly::Assignment const& _assignment) -{ - solAssert(_assignment.value, ""); - int const expectedItems = _assignment.variableNames.size(); - solAssert(expectedItems >= 1, ""); - int const stackHeight = m_stackHeight; - bool success = boost::apply_visitor(*this, *_assignment.value); - if ((m_stackHeight - stackHeight) != expectedItems) - { - m_errorReporter.declarationError( - _assignment.location, - "Variable count does not match number of values (" + - to_string(expectedItems) + - " vs. " + - to_string(m_stackHeight - stackHeight) + - ")" - ); - return false; - } - for (auto const& variableName: _assignment.variableNames) - if (!checkAssignment(variableName, 1)) - success = false; - m_info.stackHeightInfo[&_assignment] = m_stackHeight; - return success; -} - -bool AsmAnalyzer::operator()(assembly::VariableDeclaration const& _varDecl) -{ - bool success = true; - int const numVariables = _varDecl.variables.size(); - if (_varDecl.value) - { - int const stackHeight = m_stackHeight; - success = boost::apply_visitor(*this, *_varDecl.value); - if ((m_stackHeight - stackHeight) != numVariables) - { - m_errorReporter.declarationError(_varDecl.location, "Variable count mismatch."); - return false; - } - } - else - m_stackHeight += numVariables; - - for (auto const& variable: _varDecl.variables) - { - expectValidType(variable.type.str(), variable.location); - m_activeVariables.insert(&boost::get<Scope::Variable>(m_currentScope->identifiers.at(variable.name))); - } - m_info.stackHeightInfo[&_varDecl] = m_stackHeight; - return success; -} - -bool AsmAnalyzer::operator()(assembly::FunctionDefinition const& _funDef) -{ - solAssert(!_funDef.name.empty(), ""); - Block const* virtualBlock = m_info.virtualBlocks.at(&_funDef).get(); - solAssert(virtualBlock, ""); - Scope& varScope = scope(virtualBlock); - for (auto const& var: _funDef.parameters + _funDef.returnVariables) - { - expectValidType(var.type.str(), var.location); - m_activeVariables.insert(&boost::get<Scope::Variable>(varScope.identifiers.at(var.name))); - } - - int const stackHeight = m_stackHeight; - m_stackHeight = _funDef.parameters.size() + _funDef.returnVariables.size(); - - bool success = (*this)(_funDef.body); - - m_stackHeight = stackHeight; - m_info.stackHeightInfo[&_funDef] = m_stackHeight; - return success; -} - -bool AsmAnalyzer::operator()(assembly::FunctionCall const& _funCall) -{ - solAssert(!_funCall.functionName.name.empty(), ""); - bool success = true; - size_t arguments = 0; - size_t returns = 0; - if (!m_currentScope->lookup(_funCall.functionName.name, Scope::Visitor( - [&](Scope::Variable const&) - { - m_errorReporter.typeError( - _funCall.functionName.location, - "Attempt to call variable instead of function." - ); - success = false; - }, - [&](Scope::Label const&) - { - m_errorReporter.typeError( - _funCall.functionName.location, - "Attempt to call label instead of function." - ); - success = false; - }, - [&](Scope::Function const& _fun) - { - /// TODO: compare types too - arguments = _fun.arguments.size(); - returns = _fun.returns.size(); - } - ))) - { - m_errorReporter.declarationError(_funCall.functionName.location, "Function not found."); - success = false; - } - if (success) - { - if (_funCall.arguments.size() != arguments) - { - m_errorReporter.typeError( - _funCall.functionName.location, - "Expected " + to_string(arguments) + " arguments but got " + - to_string(_funCall.arguments.size()) + "." - ); - success = false; - } - } - for (auto const& arg: _funCall.arguments | boost::adaptors::reversed) - if (!expectExpression(arg)) - success = false; - m_stackHeight += int(returns) - int(arguments); - m_info.stackHeightInfo[&_funCall] = m_stackHeight; - return success; -} - -bool AsmAnalyzer::operator()(If const& _if) -{ - bool success = true; - - if (!expectExpression(*_if.condition)) - success = false; - m_stackHeight--; - - if (!(*this)(_if.body)) - success = false; - - m_info.stackHeightInfo[&_if] = m_stackHeight; - - return success; -} - -bool AsmAnalyzer::operator()(Switch const& _switch) -{ - solAssert(_switch.expression, ""); - - bool success = true; - - if (!expectExpression(*_switch.expression)) - success = false; - - set<tuple<LiteralKind, YulString>> cases; - for (auto const& _case: _switch.cases) - { - if (_case.value) - { - int const initialStackHeight = m_stackHeight; - // We cannot use "expectExpression" here because *_case.value is not a - // Statement and would be converted to a Statement otherwise. - if (!(*this)(*_case.value)) - success = false; - expectDeposit(1, initialStackHeight, _case.value->location); - m_stackHeight--; - - /// Note: the parser ensures there is only one default case - auto val = make_tuple(_case.value->kind, _case.value->value); - if (!cases.insert(val).second) - { - m_errorReporter.declarationError( - _case.location, - "Duplicate case defined" - ); - success = false; - } - } - - if (!(*this)(_case.body)) - success = false; - } - - m_stackHeight--; - m_info.stackHeightInfo[&_switch] = m_stackHeight; - - return success; -} - -bool AsmAnalyzer::operator()(assembly::ForLoop const& _for) -{ - solAssert(_for.condition, ""); - - Scope* originalScope = m_currentScope; - - bool success = true; - if (!(*this)(_for.pre)) - success = false; - // The block was closed already, but we re-open it again and stuff the - // condition, the body and the post part inside. - m_stackHeight += scope(&_for.pre).numberOfVariables(); - m_currentScope = &scope(&_for.pre); - - if (!expectExpression(*_for.condition)) - success = false; - m_stackHeight--; - if (!(*this)(_for.body)) - success = false; - if (!(*this)(_for.post)) - success = false; - - m_stackHeight -= scope(&_for.pre).numberOfVariables(); - m_info.stackHeightInfo[&_for] = m_stackHeight; - m_currentScope = originalScope; - - return success; -} - -bool AsmAnalyzer::operator()(Block const& _block) -{ - bool success = true; - auto previousScope = m_currentScope; - m_currentScope = &scope(&_block); - - int const initialStackHeight = m_stackHeight; - - for (auto const& s: _block.statements) - if (!boost::apply_visitor(*this, s)) - success = false; - - m_stackHeight -= scope(&_block).numberOfVariables(); - - int const stackDiff = m_stackHeight - initialStackHeight; - if (stackDiff != 0) - { - m_errorReporter.declarationError( - _block.location, - "Unbalanced stack at the end of a block: " + - ( - stackDiff > 0 ? - to_string(stackDiff) + string(" surplus item(s).") : - to_string(-stackDiff) + string(" missing item(s).") - ) - ); - success = false; - } - - m_info.stackHeightInfo[&_block] = m_stackHeight; - m_currentScope = previousScope; - return success; -} - -bool AsmAnalyzer::expectExpression(Expression const& _expr) -{ - bool success = true; - int const initialHeight = m_stackHeight; - if (!boost::apply_visitor(*this, _expr)) - success = false; - if (!expectDeposit(1, initialHeight, locationOf(_expr))) - success = false; - return success; -} - -bool AsmAnalyzer::expectDeposit(int _deposit, int _oldHeight, SourceLocation const& _location) -{ - if (m_stackHeight - _oldHeight != _deposit) - { - m_errorReporter.typeError( - _location, - "Expected expression to return one item to the stack, but did return " + - to_string(m_stackHeight - _oldHeight) + - " items." - ); - return false; - } - return true; -} - -bool AsmAnalyzer::checkAssignment(assembly::Identifier const& _variable, size_t _valueSize) -{ - solAssert(!_variable.name.empty(), ""); - bool success = true; - size_t numErrorsBefore = m_errorReporter.errors().size(); - size_t variableSize(-1); - if (Scope::Identifier const* var = m_currentScope->lookup(_variable.name)) - { - // Check that it is a variable - if (var->type() != typeid(Scope::Variable)) - { - m_errorReporter.typeError(_variable.location, "Assignment requires variable."); - success = false; - } - else if (!m_activeVariables.count(&boost::get<Scope::Variable>(*var))) - { - m_errorReporter.declarationError( - _variable.location, - "Variable " + _variable.name.str() + " used before it was declared." - ); - success = false; - } - variableSize = 1; - } - else if (m_resolver) - { - bool insideFunction = m_currentScope->insideFunction(); - variableSize = m_resolver(_variable, yul::IdentifierContext::LValue, insideFunction); - } - if (variableSize == size_t(-1)) - { - // Only add message if the callback did not. - if (numErrorsBefore == m_errorReporter.errors().size()) - m_errorReporter.declarationError(_variable.location, "Variable not found or variable not lvalue."); - success = false; - } - if (_valueSize == size_t(-1)) - _valueSize = variableSize == size_t(-1) ? 1 : variableSize; - - m_stackHeight -= _valueSize; - - if (_valueSize != variableSize && variableSize != size_t(-1)) - { - m_errorReporter.typeError( - _variable.location, - "Variable size (" + - to_string(variableSize) + - ") and value size (" + - to_string(_valueSize) + - ") do not match." - ); - success = false; - } - return success; -} - -Scope& AsmAnalyzer::scope(Block const* _block) -{ - solAssert(m_info.scopes.count(_block) == 1, "Scope requested but not present."); - auto scopePtr = m_info.scopes.at(_block); - solAssert(scopePtr, "Scope requested but not present."); - return *scopePtr; -} -void AsmAnalyzer::expectValidType(string const& type, SourceLocation const& _location) -{ - if (m_flavour != AsmFlavour::Yul) - return; - - if (!builtinTypes.count(type)) - m_errorReporter.typeError( - _location, - "\"" + type + "\" is not a valid type (user defined types are not yet supported)." - ); -} - -void AsmAnalyzer::warnOnInstructions(solidity::Instruction _instr, SourceLocation const& _location) -{ - // We assume that returndatacopy, returndatasize and staticcall are either all available - // or all not available. - solAssert(m_evmVersion.supportsReturndata() == m_evmVersion.hasStaticCall(), ""); - // Similarly we assume bitwise shifting and create2 go together. - solAssert(m_evmVersion.hasBitwiseShifting() == m_evmVersion.hasCreate2(), ""); - - if (_instr == solidity::Instruction::EXTCODEHASH) - m_errorReporter.warning( - _location, - "The \"" + - boost::to_lower_copy(instructionInfo(_instr).name) - + "\" instruction is not supported by the VM version \"" + - "" + m_evmVersion.name() + - "\" you are currently compiling for. " + - "It will be interpreted as an invalid instruction on this VM." - ); - else if (( - _instr == solidity::Instruction::RETURNDATACOPY || - _instr == solidity::Instruction::RETURNDATASIZE || - _instr == solidity::Instruction::STATICCALL - ) && !m_evmVersion.supportsReturndata()) - m_errorReporter.warning( - _location, - "The \"" + - boost::to_lower_copy(instructionInfo(_instr).name) - + "\" instruction is only available for Byzantium-compatible VMs. " + - "You are currently compiling for \"" + - m_evmVersion.name() + - "\", where it will be interpreted as an invalid instruction." - ); - else if (( - _instr == solidity::Instruction::SHL || - _instr == solidity::Instruction::SHR || - _instr == solidity::Instruction::SAR || - _instr == solidity::Instruction::CREATE2 - ) && !m_evmVersion.hasBitwiseShifting()) - m_errorReporter.warning( - _location, - "The \"" + - boost::to_lower_copy(instructionInfo(_instr).name) - + "\" instruction is only available for Constantinople-compatible VMs. " + - "You are currently compiling for \"" + - m_evmVersion.name() + - "\", where it will be interpreted as an invalid instruction." - ); - - if (_instr == solidity::Instruction::JUMP || _instr == solidity::Instruction::JUMPI || _instr == solidity::Instruction::JUMPDEST) - { - solAssert(m_flavour == AsmFlavour::Loose, ""); - m_errorReporter.error( - m_errorTypeForLoose ? *m_errorTypeForLoose : Error::Type::Warning, - _location, - "Jump instructions and labels are low-level EVM features that can lead to " - "incorrect stack access. Because of that they are discouraged. " - "Please consider using \"switch\", \"if\" or \"for\" statements instead." - ); - } -} - -void AsmAnalyzer::checkLooseFeature(SourceLocation const& _location, string const& _description) -{ - if (m_flavour != AsmFlavour::Loose) - solAssert(false, _description); - else if (m_errorTypeForLoose) - m_errorReporter.error(*m_errorTypeForLoose, _location, _description); -} |