Merge pull request #5416 from ethereum/develop

Merge develop into release for 0.5.0

1 files changed, 55 insertions, 0 deletions

diff --git a/libyul/optimiser/ExpressionSimplifier.h b/libyul/optimiser/ExpressionSimplifier.h
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+++ b/libyul/optimiser/ExpressionSimplifier.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/>.
+*/
+/**
+ * Optimiser component that uses the simplification rules to simplify expressions.
+ */
+
+#pragma once
+
+#include <libyul/ASTDataForward.h>
+
+#include <libyul/optimiser/ASTWalker.h>
+
+namespace dev
+{
+namespace yul
+{
+
+/**
+ * Applies simplification rules to all expressions.
+ * The component will work best if the code is in SSA form, but
+ * this is not required for correctness.
+ *
+ * Prerequisite: Disambiguator.
+ */
+class ExpressionSimplifier: public ASTModifier
+{
+public:
+	using ASTModifier::operator();
+	virtual void visit(Expression& _expression);
+
+	static void run(Block& _ast);
+private:
+	explicit ExpressionSimplifier(std::map<YulString, Expression const*> _ssaValues):
+		m_ssaValues(std::move(_ssaValues))
+	{}
+
+	std::map<YulString, Expression const*> m_ssaValues;
+};
+
+}
+}