1 files changed, 122 insertions, 0 deletions
diff --git a/libyul/optimiser/ASTWalker.h b/libyul/optimiser/ASTWalker.h
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@@ -0,0 +1,122 @@
+/*
+	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/>.
+*/
+/**
+ * Generic AST walker.
+ */
+
+#pragma once
+
+#include <libyul/ASTDataForward.h>
+
+#include <libyul/Exceptions.h>
+
+#include <boost/variant.hpp>
+#include <boost/optional.hpp>
+
+#include <vector>
+#include <set>
+#include <map>
+
+namespace dev
+{
+namespace julia
+{
+
+/**
+ * Generic AST walker.
+ */
+class ASTWalker: public boost::static_visitor<>
+{
+public:
+	virtual ~ASTWalker() = default;
+	virtual void operator()(Literal const&) {}
+	virtual void operator()(Instruction const&) { assertThrow(false, OptimizerException, ""); }
+	virtual void operator()(Identifier const&) {}
+	virtual void operator()(FunctionalInstruction const& _instr);
+	virtual void operator()(FunctionCall const& _funCall);
+	virtual void operator()(ExpressionStatement const& _statement);
+	virtual void operator()(Label const&) { assertThrow(false, OptimizerException, ""); }
+	virtual void operator()(StackAssignment const&) { assertThrow(false, OptimizerException, ""); }
+	virtual void operator()(Assignment const& _assignment);
+	virtual void operator()(VariableDeclaration const& _varDecl);
+	virtual void operator()(If const& _if);
+	virtual void operator()(Switch const& _switch);
+	virtual void operator()(FunctionDefinition const&);
+	virtual void operator()(ForLoop const&);
+	virtual void operator()(Block const& _block);
+
+	virtual void visit(Statement const& _st)
+	{
+		boost::apply_visitor(*this, _st);
+	}
+	virtual void visit(Expression const& _e)
+	{
+		boost::apply_visitor(*this, _e);
+	}
+
+protected:
+	template <class T>
+	void walkVector(T const& _statements)
+	{
+		for (auto const& statement: _statements)
+			visit(statement);
+	}
+};
+
+/**
+ * Generic AST modifier (i.e. non-const version of ASTWalker).
+ */
+class ASTModifier: public boost::static_visitor<>
+{
+public:
+	virtual ~ASTModifier() = default;
+	virtual void operator()(Literal&) {}
+	virtual void operator()(Instruction&) { assertThrow(false, OptimizerException, ""); }
+	virtual void operator()(Identifier&) {}
+	virtual void operator()(FunctionalInstruction& _instr);
+	virtual void operator()(FunctionCall& _funCall);
+	virtual void operator()(ExpressionStatement& _statement);
+	virtual void operator()(Label&) { assertThrow(false, OptimizerException, ""); }
+	virtual void operator()(StackAssignment&) { assertThrow(false, OptimizerException, ""); }
+	virtual void operator()(Assignment& _assignment);
+	virtual void operator()(VariableDeclaration& _varDecl);
+	virtual void operator()(If& _if);
+	virtual void operator()(Switch& _switch);
+	virtual void operator()(FunctionDefinition&);
+	virtual void operator()(ForLoop&);
+	virtual void operator()(Block& _block);
+
+	virtual void visit(Statement& _st)
+	{
+		boost::apply_visitor(*this, _st);
+	}
+	virtual void visit(Expression& _e)
+	{
+		boost::apply_visitor(*this, _e);
+	}
+
+protected:
+	template <class T>
+	void walkVector(T&& _statements)
+	{
+		for (auto& st: _statements)
+			visit(st);
+	}
+};
+
+}
+}