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Diffstat (limited to 'libsolidity/ExpressionCompiler.h')
| -rw-r--r-- | libsolidity/ExpressionCompiler.h | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/libsolidity/ExpressionCompiler.h b/libsolidity/ExpressionCompiler.h new file mode 100644 index 00000000..642560c6 --- /dev/null +++ b/libsolidity/ExpressionCompiler.h @@ -0,0 +1,134 @@ +/* + This file is part of cpp-ethereum. + + cpp-ethereum 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. + + cpp-ethereum 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 cpp-ethereum. If not, see <http://www.gnu.org/licenses/>. +*/ +/** + * @author Christian <c@ethdev.com> + * @author Gav Wood <g@ethdev.com> + * @date 2014 + * Solidity AST to EVM bytecode compiler for expressions. + */ + +#include <functional> +#include <memory> +#include <boost/noncopyable.hpp> +#include <libdevcore/Common.h> +#include <libevmasm/SourceLocation.h> +#include <libsolidity/ASTVisitor.h> +#include <libsolidity/LValue.h> +#include <libsolidity/Utils.h> + +namespace dev { +namespace eth +{ +class AssemblyItem; // forward +} +namespace solidity { + +// forward declarations +class CompilerContext; +class CompilerUtils; +class Type; +class IntegerType; +class ArrayType; + +/** + * Compiler for expressions, i.e. converts an AST tree whose root is an Expression into a stream + * of EVM instructions. It needs a compiler context that is the same for the whole compilation + * unit. + */ +class ExpressionCompiler: private ASTConstVisitor +{ +public: + /// Appends code for a State Variable accessor function + static void appendStateVariableAccessor(CompilerContext& _context, VariableDeclaration const& _varDecl, bool _optimize = false); + + explicit ExpressionCompiler(CompilerContext& _compilerContext, bool _optimize = false): + m_optimize(_optimize), m_context(_compilerContext) {} + + /// Compile the given @a _expression and leave its value on the stack. + void compile(Expression const& _expression); + + /// Appends code to set a state variable to its initial value/expression. + void appendStateVariableInitialization(VariableDeclaration const& _varDecl); + + /// Appends code for a State Variable accessor function + void appendStateVariableAccessor(VariableDeclaration const& _varDecl); + +private: + virtual bool visit(Assignment const& _assignment) override; + virtual bool visit(UnaryOperation const& _unaryOperation) override; + virtual bool visit(BinaryOperation const& _binaryOperation) override; + virtual bool visit(FunctionCall const& _functionCall) override; + virtual bool visit(NewExpression const& _newExpression) override; + virtual void endVisit(MemberAccess const& _memberAccess) override; + virtual bool visit(IndexAccess const& _indexAccess) override; + virtual void endVisit(Identifier const& _identifier) override; + virtual void endVisit(Literal const& _literal) override; + + ///@{ + ///@name Append code for various operator types + void appendAndOrOperatorCode(BinaryOperation const& _binaryOperation); + void appendCompareOperatorCode(Token::Value _operator, Type const& _type); + void appendOrdinaryBinaryOperatorCode(Token::Value _operator, Type const& _type); + + void appendArithmeticOperatorCode(Token::Value _operator, Type const& _type); + void appendBitOperatorCode(Token::Value _operator); + void appendShiftOperatorCode(Token::Value _operator); + /// @} + + /// Appends code to call a function of the given type with the given arguments. + void appendExternalFunctionCall( + FunctionType const& _functionType, + std::vector<ASTPointer<Expression const>> const& _arguments + ); + /// Appends code that evaluates a single expression and moves the result to memory. The memory offset is + /// expected to be on the stack and is updated by this call. + void appendExpressionCopyToMemory(Type const& _expectedType, Expression const& _expression); + + /// Sets the current LValue to a new one (of the appropriate type) from the given declaration. + /// Also retrieves the value if it was not requested by @a _expression. + void setLValueFromDeclaration(Declaration const& _declaration, Expression const& _expression); + /// Sets the current LValue to a StorageItem holding the type of @a _expression. The reference is assumed + /// to be on the stack. + /// Also retrieves the value if it was not requested by @a _expression. + void setLValueToStorageItem(Expression const& _expression); + /// Sets the current LValue to a new LValue constructed from the arguments. + /// Also retrieves the value if it was not requested by @a _expression. + template <class _LValueType, class... _Arguments> + void setLValue(Expression const& _expression, _Arguments const&... _arguments); + + /// @returns the CompilerUtils object containing the current context. + CompilerUtils utils(); + + bool m_optimize; + CompilerContext& m_context; + std::unique_ptr<LValue> m_currentLValue; + +}; + +template <class _LValueType, class... _Arguments> +void ExpressionCompiler::setLValue(Expression const& _expression, _Arguments const&... _arguments) +{ + solAssert(!m_currentLValue, "Current LValue not reset before trying to set new one."); + std::unique_ptr<_LValueType> lvalue(new _LValueType(m_context, _arguments...)); + if (_expression.lvalueRequested()) + m_currentLValue = move(lvalue); + else + lvalue->retrieveValue(_expression.getLocation(), true); +} + +} +} |