[Yul] leave statement.

libyul/backends/evm/EVMCodeTransform.cpp

@@ -490,6 +490,9 @@ void CodeTransform::operator()(FunctionDefinition const& _function)
 		m_assembly.appendConstant(u256(0));
 	}
 
+	m_context->functionExitPoints.push(
+		CodeTransformContext::JumpInfo{m_assembly.newLabelId(), m_assembly.stackHeight()}
+	);
 	try
 	{
 		CodeTransform(
@@ -518,6 +521,9 @@ void CodeTransform::operator()(FunctionDefinition const& _function)
 		stackError(std::move(error), height);
 	}
 
+	m_assembly.appendLabel(m_context->functionExitPoints.top().label);
+	m_context->functionExitPoints.pop();
+
 	{
 		// The stack layout here is:
 		// <return label>? <arguments...> <return values...>
@@ -643,6 +649,17 @@ void CodeTransform::operator()(Continue const& _continue)
 	checkStackHeight(&_continue);
 }
 
+void CodeTransform::operator()(Leave const& _leave)
+{
+	yulAssert(!m_context->functionExitPoints.empty(), "Invalid leave-statement. Requires surrounding function in code generation.");
+	m_assembly.setSourceLocation(_leave.location);
+
+	Context::JumpInfo const& jump = m_context->functionExitPoints.top();
+	m_assembly.appendJumpTo(jump.label, appendPopUntil(jump.targetStackHeight));
+
+	checkStackHeight(&_leave);
+}
+
 void CodeTransform::operator()(Block const& _block)
 {
 	Scope* originalScope = m_scope;

libyul/backends/evm/EVMCodeTransform.h

@@ -73,6 +73,7 @@ struct CodeTransformContext
 	};
 
 	std::stack<ForLoopLabels> forLoopStack;
+	std::stack<JumpInfo> functionExitPoints;
 };
 
 /**
@@ -185,6 +186,7 @@ public:
 	void operator()(ForLoop const&);
 	void operator()(Break const&);
 	void operator()(Continue const&);
+	void operator()(Leave const&);
 	void operator()(Block const& _block);
 
 private: