Code generation (missing external access and source locations).

1 files changed, 263 insertions, 0 deletions

diff --git a/libsolidity/inlineasm/AsmCodeGen.cpp b/libsolidity/inlineasm/AsmCodeGen.cpp
new file mode 100644
index 00000000..89e95bc1
--- /dev/null
+++ b/libsolidity/inlineasm/AsmCodeGen.cpp
@@ -0,0 +1,263 @@
+/*
+	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>
+ * @date 2016
+ * Code-generating part of inline assembly.
+ */
+
+#include <libsolidity/inlineasm/AsmCodeGen.h>
+#include <memory>
+#include <functional>
+#include <libevmasm/Assembly.h>
+#include <libevmasm/SourceLocation.h>
+#include <libsolidity/inlineasm/AsmParser.h>
+#include <libsolidity/inlineasm/AsmData.h>
+
+using namespace std;
+using namespace dev;
+using namespace dev::solidity;
+using namespace dev::solidity::assembly;
+
+struct GeneratorState
+{
+	explicit GeneratorState(ErrorList& _errors): errors(_errors) {}
+
+	void addError(Error::Type _type, std::string const& _description, SourceLocation const& _location = SourceLocation())
+	{
+		auto err = make_shared<Error>(_type);
+		if (!_location.isEmpty())
+			*err << errinfo_sourceLocation(_location);
+		*err << errinfo_comment(_description);
+		errors.push_back(err);
+	}
+
+	int const* findVariable(string const& _variableName) const
+	{
+		auto localVariable = find_if(
+			variables.rbegin(),
+			variables.rend(),
+			[&](pair<string, int> const& _var) { return _var.first == _variableName; }
+		);
+		return localVariable != variables.rend() ? &localVariable->second : nullptr;
+	}
+	eth::AssemblyItem const* findLabel(string const& _labelName) const
+	{
+		auto label = find_if(
+			labels.begin(),
+			labels.end(),
+			[&](pair<string, eth::AssemblyItem> const& _label) { return _label.first == _labelName; }
+		);
+		return label != labels.end() ? &label->second : nullptr;
+	}
+
+	eth::Assembly assembly;
+	map<string, eth::AssemblyItem> labels;
+	vector<pair<string, int>> variables; ///< name plus stack height
+	ErrorList& errors;
+};
+
+/**
+ * Scans the inline assembly data for labels, creates tags in the assembly and searches for
+ * duplicate labels.
+ */
+class LabelOrganizer: public boost::static_visitor<>
+{
+public:
+	LabelOrganizer(GeneratorState& _state): m_state(_state) {}
+
+	template <class T>
+	void operator()(T const& /*_item*/) { }
+	void operator()(Label const& _item)
+	{
+		if (m_state.labels.count(_item.name))
+			//@TODO location and secondary location
+			m_state.addError(Error::Type::DeclarationError, "Label " + _item.name + " declared twice.");
+		m_state.labels.insert(make_pair(_item.name, m_state.assembly.newTag()));
+	}
+	void operator()(assembly::Block const& _block)
+	{
+		std::for_each(_block.statements.begin(), _block.statements.end(), boost::apply_visitor(*this));
+	}
+
+private:
+	GeneratorState& m_state;
+};
+
+class CodeTransform: public boost::static_visitor<>
+{
+public:
+	/// Create the code transformer which appends assembly to _state.assembly when called
+	/// with parsed assembly data.
+	/// @param _identifierAccess used to resolve identifiers external to the inline assembly
+	explicit CodeTransform(
+		GeneratorState& _state,
+		assembly::CodeGenerator::IdentifierAccess const& _identifierAccess = assembly::CodeGenerator::IdentifierAccess()
+	):
+		m_state(_state)
+	{
+		if (_identifierAccess)
+			m_identifierAccess = _identifierAccess;
+		else
+			m_identifierAccess = [](assembly::Identifier const&, eth::Assembly&, CodeGenerator::IdentifierContext) { return false; };
+	}
+
+	void operator()(Instruction const& _instruction)
+	{
+		m_state.assembly.append(_instruction.instruction);
+	}
+	void operator()(assembly::Literal const& _literal)
+	{
+		if (_literal.isNumber)
+			m_state.assembly.append(u256(_literal.value));
+		else if (_literal.value.size() > 32)
+			m_state.addError(
+				Error::Type::TypeError,
+				"String literal too long (" + boost::lexical_cast<string>(_literal.value.size()) + " > 32)"
+			);
+		else
+			m_state.assembly.append(_literal.value);
+	}
+	void operator()(assembly::Identifier const& _identifier)
+	{
+		// First search local variables, then labels, then externals.
+		if (int const* stackHeight = m_state.findVariable(_identifier.name))
+		{
+			int heightDiff = m_state.assembly.deposit() - *stackHeight;
+			if (heightDiff <= 0 || heightDiff > 16)
+				//@TODO location
+				m_state.addError(
+					Error::Type::TypeError,
+					"Variable inaccessible, too deep inside stack (" + boost::lexical_cast<string>(heightDiff) + ")"
+				);
+			else
+				m_state.assembly.append(eth::dupInstruction(heightDiff));
+			return;
+		}
+		else if (eth::AssemblyItem const* label = m_state.findLabel(_identifier.name))
+			m_state.assembly.append(label->pushTag());
+		else if (!m_identifierAccess(_identifier, m_state.assembly, CodeGenerator::IdentifierContext::RValue))
+			m_state.addError(
+				Error::Type::DeclarationError,
+				"Identifier \"" + string(_identifier.name) + "\" not found or not unique"
+			);
+	}
+	void operator()(FunctionalInstruction const& _instr)
+	{
+		for (auto it = _instr.arguments.rbegin(); it != _instr.arguments.rend(); ++it)
+		{
+			int height = m_state.assembly.deposit();
+			boost::apply_visitor(*this, *it);
+			expectDeposit(1, height);
+		}
+		(*this)(_instr.instruction);
+	}
+	void operator()(Label const& _label)
+	{
+		m_state.assembly.append(m_state.labels.at(_label.name));
+	}
+	void operator()(assembly::Assignment const& _assignment)
+	{
+		generateAssignment(_assignment.variableName);
+	}
+	void operator()(FunctionalAssignment const& _assignment)
+	{
+		int height = m_state.assembly.deposit();
+		boost::apply_visitor(*this, *_assignment.value);
+		expectDeposit(1, height);
+		generateAssignment(_assignment.variableName);
+	}
+	void operator()(assembly::VariableDeclaration const& _varDecl)
+	{
+		int height = m_state.assembly.deposit();
+		boost::apply_visitor(*this, *_varDecl.value);
+		expectDeposit(1, height);
+		m_state.variables.push_back(make_pair(_varDecl.name, height));
+	}
+	void operator()(assembly::Block const& _block)
+	{
+		size_t numVariables = m_state.variables.size();
+		std::for_each(_block.statements.begin(), _block.statements.end(), boost::apply_visitor(*this));
+		// pop variables
+		//@TODO check height before and after
+		while (m_state.variables.size() > numVariables)
+		{
+			m_state.assembly.append(eth::Instruction::POP);
+			m_state.variables.pop_back();
+		}
+	}
+
+private:
+	void generateAssignment(assembly::Identifier const& _variableName)
+	{
+		if (int const* stackHeight = m_state.findVariable(_variableName.name))
+		{
+			int heightDiff = m_state.assembly.deposit() - *stackHeight - 1;
+			if (heightDiff <= 0 || heightDiff > 16)
+				//@TODO location
+				m_state.addError(
+					Error::Type::TypeError,
+					"Variable inaccessible, too deep inside stack (" + boost::lexical_cast<string>(heightDiff) + ")"
+				);
+			else
+			{
+				m_state.assembly.append(eth::swapInstruction(heightDiff));
+				m_state.assembly.append(eth::Instruction::POP);
+			}
+			return;
+		}
+		else if (!m_identifierAccess(_variableName, m_state.assembly, CodeGenerator::IdentifierContext::LValue))
+			m_state.addError(
+				Error::Type::DeclarationError,
+				"Identifier \"" + string(_variableName.name) + "\" not found, not unique or not lvalue."
+			);
+	}
+
+	void expectDeposit(int _deposit, int _oldHeight)
+	{
+		if (m_state.assembly.deposit() != _oldHeight + 1)
+			//@TODO location
+			m_state.addError(Error::Type::TypeError,
+				"Expected instruction(s) to deposit " +
+				boost::lexical_cast<string>(_deposit) +
+				" item(s) to the stack, but did deposit " +
+				boost::lexical_cast<string>(m_state.assembly.deposit() - _oldHeight) +
+				" item(s)."
+			);
+	}
+
+	GeneratorState& m_state;
+	assembly::CodeGenerator::IdentifierAccess m_identifierAccess;
+};
+
+bool assembly::CodeGenerator::typeCheck(assembly::CodeGenerator::IdentifierAccess const& _identifierAccess)
+{
+	size_t initialErrorLen = m_errors.size();
+	GeneratorState state(m_errors);
+	(LabelOrganizer(state))(m_parsedData);
+	(CodeTransform(state, _identifierAccess))(m_parsedData);
+	return m_errors.size() == initialErrorLen;
+}
+
+eth::Assembly assembly::CodeGenerator::assemble(assembly::CodeGenerator::IdentifierAccess const& _identifierAccess)
+{
+	GeneratorState state(m_errors);
+	(LabelOrganizer(state))(m_parsedData);
+	(CodeTransform(state, _identifierAccess))(m_parsedData);
+	return state.assembly;
+}
+