1 files changed, 70 insertions, 0 deletions
diff --git a/libyul/optimiser/InlinableExpressionFunctionFinder.cpp b/libyul/optimiser/InlinableExpressionFunctionFinder.cpp
new file mode 100644
index 00000000..e6332f3a
--- /dev/null
+++ b/libyul/optimiser/InlinableExpressionFunctionFinder.cpp
@@ -0,0 +1,70 @@
+/*
+	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 identifies functions to be inlined.
+ */
+
+#include <libyul/optimiser/InlinableExpressionFunctionFinder.h>
+
+#include <libyul/optimiser/Utilities.h>
+
+#include <libsolidity/inlineasm/AsmData.h>
+
+using namespace std;
+using namespace dev;
+using namespace dev::julia;
+
+void InlinableExpressionFunctionFinder::operator()(Identifier const& _identifier)
+{
+	checkAllowed(_identifier.name);
+	ASTWalker::operator()(_identifier);
+}
+
+void InlinableExpressionFunctionFinder::operator()(FunctionCall const& _funCall)
+{
+	checkAllowed(_funCall.functionName.name);
+	ASTWalker::operator()(_funCall);
+}
+
+void InlinableExpressionFunctionFinder::operator()(FunctionDefinition const& _function)
+{
+	if (_function.returnVariables.size() == 1 && _function.body.statements.size() == 1)
+	{
+		string const& retVariable = _function.returnVariables.front().name;
+		Statement const& bodyStatement = _function.body.statements.front();
+		if (bodyStatement.type() == typeid(Assignment))
+		{
+			Assignment const& assignment = boost::get<Assignment>(bodyStatement);
+			if (assignment.variableNames.size() == 1 && assignment.variableNames.front().name == retVariable)
+			{
+				// FIXME: use code size metric here
+
+				// We cannot overwrite previous settings, because this function definition
+				// would not be valid here if we were searching inside a functionally inlinable
+				// function body.
+				assertThrow(m_disallowedIdentifiers.empty() && !m_foundDisallowedIdentifier, OptimizerException, "");
+				m_disallowedIdentifiers = set<string>{retVariable, _function.name};
+				boost::apply_visitor(*this, *assignment.value);
+				if (!m_foundDisallowedIdentifier)
+					m_inlinableFunctions[_function.name] = &_function;
+				m_disallowedIdentifiers.clear();
+				m_foundDisallowedIdentifier = false;
+			}
+		}
+	}
+	ASTWalker::operator()(_function.body);
+}