From 3c8b777b9b7e438e16a3cb60dece5af3753fc8d4 Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Wed, 20 Dec 2017 13:47:51 +0100
Subject: References counter.

---
 libjulia/optimiser/ASTWalker.h       |  4 ++--
 libjulia/optimiser/NameCollector.cpp | 25 +++++++++++++++++++++++++
 libjulia/optimiser/NameCollector.h   | 20 +++++++++++++++++++-
 3 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/libjulia/optimiser/ASTWalker.h b/libjulia/optimiser/ASTWalker.h
index dbf8194b..97891381 100644
--- a/libjulia/optimiser/ASTWalker.h
+++ b/libjulia/optimiser/ASTWalker.h
@@ -71,8 +71,8 @@ protected:
 	template <class T>
 	void walkVector(T const& _statements)
 	{
-		for (auto const& st: _statements)
-			visit(st);
+		for (auto const& statement: _statements)
+			visit(statement);
 	}
 };
 
diff --git a/libjulia/optimiser/NameCollector.cpp b/libjulia/optimiser/NameCollector.cpp
index 7b4c4793..f94104b7 100644
--- a/libjulia/optimiser/NameCollector.cpp
+++ b/libjulia/optimiser/NameCollector.cpp
@@ -42,3 +42,28 @@ void NameCollector::operator ()(FunctionDefinition const& _funDef)
 		m_names.insert(ret.name);
 	ASTWalker::operator ()(_funDef);
 }
+
+void ReferencesCounter::operator()(Identifier const& _identifier)
+{
+	++m_references[_identifier.name];
+}
+
+void ReferencesCounter::operator()(FunctionCall const& _funCall)
+{
+	++m_references[_funCall.functionName.name];
+	ASTWalker::operator()(_funCall);
+}
+
+map<string, size_t> ReferencesCounter::countReferences(Block const& _block)
+{
+	ReferencesCounter counter;
+	counter(_block);
+	return counter.references();
+}
+
+map<string, size_t> ReferencesCounter::countReferences(Expression const& _expression)
+{
+	ReferencesCounter counter;
+	counter.visit(_expression);
+	return counter.references();
+}
diff --git a/libjulia/optimiser/NameCollector.h b/libjulia/optimiser/NameCollector.h
index b7e38f46..7fe386f7 100644
--- a/libjulia/optimiser/NameCollector.h
+++ b/libjulia/optimiser/NameCollector.h
@@ -15,7 +15,7 @@
 	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
 */
 /**
- * Specific AST walker that collects all defined names.
+ * Specific AST walkers that collect facts about identifiers and definitions.
  */
 
 #pragma once
@@ -48,5 +48,23 @@ private:
 	std::map<std::string, FunctionDefinition const*> m_functions;
 };
 
+/**
+ * Specific AST walker that counts all references to all declarations.
+ */
+class ReferencesCounter: public ASTWalker
+{
+public:
+	using ASTWalker::operator ();
+	virtual void operator()(Identifier const& _identifier);
+	virtual void operator()(FunctionCall const& _funCall);
+
+	static std::map<std::string, size_t> countReferences(Block const& _block);
+	static std::map<std::string, size_t> countReferences(Expression const& _expression);
+
+	std::map<std::string, size_t> const& references() const { return m_references; }
+private:
+	std::map<std::string, size_t> m_references;
+};
+
 }
 }
-- 
cgit