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diff --git a/libsolidity/inlineasm/AsmAnalysis.h b/libsolidity/inlineasm/AsmAnalysis.h
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+/*
+	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/>.
+*/
+/**
+ * Analysis part of inline assembly.
+ */
+
+#pragma once
+
+#include <libsolidity/interface/Exceptions.h>
+
+#include <boost/variant.hpp>
+
+#include <functional>
+#include <memory>
+
+namespace dev
+{
+namespace solidity
+{
+namespace assembly
+{
+
+struct Literal;
+struct Block;
+struct Label;
+struct FunctionalInstruction;
+struct FunctionalAssignment;
+struct VariableDeclaration;
+struct Instruction;
+struct Identifier;
+struct Assignment;
+struct FunctionDefinition;
+struct FunctionCall;
+
+template <class...>
+struct GenericVisitor{};
+
+template <class Visitable, class... Others>
+struct GenericVisitor<Visitable, Others...>: public GenericVisitor<Others...>
+{
+	using GenericVisitor<Others...>::operator ();
+	explicit GenericVisitor(
+		std::function<void(Visitable&)> _visitor,
+		std::function<void(Others&)>... _otherVisitors
+	):
+		GenericVisitor<Others...>(_otherVisitors...),
+		m_visitor(_visitor)
+	{}
+
+	void operator()(Visitable& _v) const { m_visitor(_v); }
+
+	std::function<void(Visitable&)> m_visitor;
+};
+template <>
+struct GenericVisitor<>: public boost::static_visitor<> {
+	void operator()() const {}
+};
+
+
+struct Scope
+{
+	struct Variable
+	{
+		int stackHeight = 0;
+		bool active = false;
+	};
+
+	struct Label
+	{
+		size_t id = unassignedLabelId;
+		static const size_t errorLabelId = -1;
+		static const size_t unassignedLabelId = 0;
+	};
+
+	struct Function
+	{
+		Function(size_t _arguments, size_t _returns): arguments(_arguments), returns(_returns) {}
+		size_t arguments = 0;
+		size_t returns = 0;
+	};
+
+	using Identifier = boost::variant<Variable, Label, Function>;
+	using Visitor = GenericVisitor<Variable const, Label const, Function const>;
+	using NonconstVisitor = GenericVisitor<Variable, Label, Function>;
+
+	bool registerVariable(std::string const& _name);
+	bool registerLabel(std::string const& _name);
+	bool registerFunction(std::string const& _name, size_t _arguments, size_t _returns);
+
+	/// Looks up the identifier in this or super scopes (stops and function and assembly boundaries)
+	/// and returns a valid pointer if found or a nullptr if not found.
+	/// The pointer will be invalidated if the scope is modified.
+	Identifier* lookup(std::string const& _name);
+	/// Looks up the identifier in this and super scopes (stops and function and assembly boundaries)
+	/// and calls the visitor, returns false if not found.
+	template <class V>
+	bool lookup(std::string const& _name, V const& _visitor)
+	{
+		if (Identifier* id = lookup(_name))
+		{
+			boost::apply_visitor(_visitor, *id);
+			return true;
+		}
+		else
+			return false;
+	}
+	/// @returns true if the name exists in this scope or in super scopes (also searches
+	/// across function and assembly boundaries).
+	bool exists(std::string const& _name);
+	Scope* superScope = nullptr;
+	/// If true, identifiers from the super scope are not visible here, but they are still
+	/// taken into account to prevent shadowing.
+	bool closedScope = false;
+	std::map<std::string, Identifier> identifiers;
+};
+
+
+class AsmAnalyzer: public boost::static_visitor<bool>
+{
+public:
+	using Scopes = std::map<assembly::Block const*, std::shared_ptr<Scope>>;
+	AsmAnalyzer(Scopes& _scopes, ErrorList& _errors);
+
+	bool operator()(assembly::Instruction const&) { return true; }
+	bool operator()(assembly::Literal const& _literal);
+	bool operator()(assembly::Identifier const&) { return true; }
+	bool operator()(assembly::FunctionalInstruction const& _functionalInstruction);
+	bool operator()(assembly::Label const& _label);
+	bool operator()(assembly::Assignment const&) { return true; }
+	bool operator()(assembly::FunctionalAssignment const& _functionalAssignment);
+	bool operator()(assembly::VariableDeclaration const& _variableDeclaration);
+	bool operator()(assembly::FunctionDefinition const& _functionDefinition);
+	bool operator()(assembly::FunctionCall const& _functionCall);
+	bool operator()(assembly::Block const& _block);
+
+private:
+	Scope* m_currentScope = nullptr;
+	Scopes& m_scopes;
+	ErrorList& m_errors;
+};
+
+}
+}
+}