Side effects propagator.

libyul/SideEffects.h

@@ -73,6 +73,16 @@ struct SideEffects
 		*this = *this + _other;
 		return *this;
 	}
+
+	bool operator==(SideEffects const& _other) const
+	{
+		return
+			movable == _other.movable &&
+			sideEffectFree == _other.sideEffectFree &&
+			sideEffectFreeIfNoMSize == _other.sideEffectFreeIfNoMSize &&
+			invalidatesStorage == _other.invalidatesStorage &&
+			invalidatesMemory == _other.invalidatesMemory;
+	}
 };
 
 }

libyul/optimiser/CallGraphGenerator.cpp

@@ -29,18 +29,24 @@ using namespace std;
 using namespace dev;
 using namespace yul;
 
+map<YulString, set<YulString>> CallGraphGenerator::callGraph(Block const& _ast)
+{
+	CallGraphGenerator gen;
+	gen(_ast);
+	return std::move(gen.m_callGraph);
+}
 
 void CallGraphGenerator::operator()(FunctionalInstruction const& _functionalInstruction)
 {
-	m_callGraph.insert(m_currentFunction, YulString{
+	string name = dev::eth::instructionInfo(_functionalInstruction.instruction).name;
-		dev::eth::instructionInfo(_functionalInstruction.instruction).name
+	std::transform(name.begin(), name.end(), name.begin(), [](unsigned char _c) { return tolower(_c); });
-	});
+	m_callGraph[m_currentFunction].insert(YulString{name});
 	ASTWalker::operator()(_functionalInstruction);
 }
 
 void CallGraphGenerator::operator()(FunctionCall const& _functionCall)
 {
-	m_callGraph.insert(m_currentFunction, _functionCall.functionName.name);
+	m_callGraph[m_currentFunction].insert(_functionCall.functionName.name);
 	ASTWalker::operator()(_functionCall);
 }
 
@@ -48,7 +54,14 @@ void CallGraphGenerator::operator()(FunctionDefinition const& _functionDefinitio
 {
 	YulString previousFunction = m_currentFunction;
 	m_currentFunction = _functionDefinition.name;
+	yulAssert(m_callGraph.count(m_currentFunction) == 0, "");
+	m_callGraph[m_currentFunction] = {};
 	ASTWalker::operator()(_functionDefinition);
 	m_currentFunction = previousFunction;
 }
 
+CallGraphGenerator::CallGraphGenerator()
+{
+	m_callGraph[YulString{}] = {};
+}
+

libyul/optimiser/CallGraphGenerator.h

@@ -40,8 +40,7 @@ namespace yul
 class CallGraphGenerator: public ASTWalker
 {
 public:
-	/// @returns the call graph of the visited AST.
+	static std::map<YulString, std::set<YulString>> callGraph(Block const& _ast);
-	InvertibleRelation<YulString> const& callGraph() const { return m_callGraph; }
 
 	using ASTWalker::operator();
 	void operator()(FunctionalInstruction const& _functionalInstruction) override;
@@ -49,7 +48,9 @@ public:
 	void operator()(FunctionDefinition const& _functionDefinition) override;
 
 private:
-	InvertibleRelation<YulString> m_callGraph;
+	CallGraphGenerator();
+
+	std::map<YulString, std::set<YulString>> m_callGraph;
 	/// The name of the function we are currently visiting during traversal.
 	YulString m_currentFunction;
 };

libyul/optimiser/Semantics.cpp

@@ -28,6 +28,7 @@
 #include <libevmasm/SemanticInformation.h>
 
 #include <libdevcore/CommonData.h>
+#include <libdevcore/Algorithms.h>
 
 using namespace std;
 using namespace dev;
@@ -93,6 +94,33 @@ void MSizeFinder::operator()(FunctionCall const& _functionCall)
 			m_msizeFound = true;
 }
 
+
+map<YulString, SideEffects> SideEffectsPropagator::sideEffects(
+	Dialect const& _dialect,
+	map<YulString, std::set<YulString>> const& _directCallGraph
+)
+{
+	map<YulString, SideEffects> ret;
+	for (auto const& call: _directCallGraph)
+	{
+		YulString funName = call.first;
+		SideEffects sideEffects;
+		BreadthFirstSearch<YulString>{call.second, {funName}}.run(
+			[&](YulString _function, auto&& _addChild) {
+				if (sideEffects == SideEffects::worst())
+					return;
+				if (BuiltinFunction const* f = _dialect.builtin(_function))
+					sideEffects += f->sideEffects;
+				else
+					for (YulString callee: _directCallGraph.at(_function))
+						_addChild(callee);
+			}
+		);
+		ret[funName] = sideEffects;
+	}
+	return ret;
+}
+
 MovableChecker::MovableChecker(Dialect const& _dialect, Expression const& _expression):
 	MovableChecker(_dialect)
 {

libyul/optimiser/Semantics.h

@@ -62,6 +62,21 @@ private:
 	SideEffects m_sideEffects;
 };
 
+/**
+ * This class can be used to determine the side-effects of user-defined functions.
+ *
+ * It is given a dialect and a mapping that represents the direct calls from user-defined
+ * functions to other user-defined functions and built-in functions.
+ */
+class SideEffectsPropagator
+{
+public:
+	static std::map<YulString, SideEffects> sideEffects(
+		Dialect const& _dialect,
+		std::map<YulString, std::set<YulString>> const& _directCallGraph
+	);
+};
+
 /**
  * Class that can be used to find out if certain code contains the MSize instruction.
  *