Merge pull request #6787 from ethereum/sol2yul-ctor-code

Improve constructor-code codegen (wrt. state variable initialization)

libsolidity/codegen/ir/IRGenerator.cpp

@@ -39,6 +39,9 @@
 #include <liblangutil/SourceReferenceFormatter.h>
 
 #include <boost/algorithm/string/predicate.hpp>
+#include <boost/range/adaptor/reversed.hpp>
+
+#include <sstream>
 
 using namespace std;
 using namespace dev;
@@ -177,19 +180,45 @@ string IRGenerator::generateGetter(VariableDeclaration const& _varDecl)
 
 string IRGenerator::constructorCode(ContractDefinition const& _contract)
 {
-	// TODO initialize state variables in base to derived order.
-	// TODO base constructors
-	// TODO callValueCheck if there is no constructor.
-	if (FunctionDefinition const* constructor = _contract.constructor())
+	// Initialization of state variables in base-to-derived order.
+	solAssert(!_contract.isLibrary(), "Tried to initialize state variables of library.");
+
+	using boost::adaptors::reverse;
+
+	ostringstream out;
+
+	FunctionDefinition const* constructor = _contract.constructor();
+	if (constructor && !constructor->isPayable())
+		out << callValueCheck();
+
+	for (ContractDefinition const* contract: reverse(_contract.annotation().linearizedBaseContracts))
 	{
-		string out;
-		if (!constructor->isPayable())
-			out = callValueCheck();
-		solUnimplementedAssert(constructor->parameters().empty(), "");
-		return move(out) + m_context.functionName(*constructor) + "()\n";
+		out <<
+			"\n// Begin state variable initialization for contract \"" <<
+			contract->name() <<
+			"\" (" <<
+			contract->stateVariables().size() <<
+			" variables)\n";
+
+		IRGeneratorForStatements generator{m_context, m_utils};
+		for (VariableDeclaration const* variable: contract->stateVariables())
+			if (!variable->isConstant())
+				generator.initializeStateVar(*variable);
+		out << generator.code();
+
+		out << "// End state variable initialization for contract \"" << contract->name() << "\".\n";
 	}
 
-	return {};
+	if (constructor)
+	{
+		solUnimplementedAssert(constructor->parameters().empty(), "");
+
+		// TODO base constructors
+
+		out << m_context.functionName(*constructor) + "()\n";
+	}
+
+	return out.str();
 }
 
 string IRGenerator::deployCode(ContractDefinition const& _contract)

libsolidity/codegen/ir/IRGeneratorForStatements.cpp

@@ -133,6 +133,21 @@ string IRGeneratorForStatements::code() const
 	return m_code.str();
 }
 
+void IRGeneratorForStatements::initializeStateVar(VariableDeclaration const& _varDecl)
+{
+	solAssert(m_context.isStateVariable(_varDecl), "Must be a state variable.");
+	solAssert(!_varDecl.isConstant(), "");
+	if (_varDecl.value())
+	{
+		_varDecl.value()->accept(*this);
+		string value = m_context.newYulVariable();
+		Type const& varType = *_varDecl.type();
+
+		m_code << "let " << value << " := " << expressionAsType(*_varDecl.value(), varType) << "\n";
+		m_code << IRStorageItem{m_context, _varDecl}.storeValue(value, varType);
+	}
+}
+
 void IRGeneratorForStatements::endVisit(VariableDeclarationStatement const& _varDeclStatement)
 {
 	for (auto const& decl: _varDeclStatement.declarations())

libsolidity/codegen/ir/IRGeneratorForStatements.h

@@ -45,6 +45,9 @@ public:
 
 	std::string code() const;
 
+	/// Generates code to initialize the given state variable.
+	void initializeStateVar(VariableDeclaration const& _varDecl);
+
 	void endVisit(VariableDeclarationStatement const& _variableDeclaration) override;
 	bool visit(Assignment const& _assignment) override;
 	bool visit(TupleExpression const& _tuple) override;

test/cmdlineTests/standard_ir_requested/output.json

@@ -10,6 +10,9 @@ object \"C_6\" {
     code {
         mstore(64, 128)
 
+        // Begin state variable initialization for contract \"C\" (0 variables)
+        // End state variable initialization for contract \"C\".
+
 
         codecopy(0, dataoffset(\"C_6_deployed\"), datasize(\"C_6_deployed\"))
         return(0, datasize(\"C_6_deployed\"))

test/libsolidity/SolidityEndToEndTest.cpp

@@ -7921,8 +7921,10 @@ BOOST_AUTO_TEST_CASE(accessor_for_state_variable)
 		}
 	)";
 
-	compileAndRun(sourceCode);
-	ABI_CHECK(callContractFunction("ticketPrice()"), encodeArgs(u256(500)));
+	ALSO_VIA_YUL(
+		compileAndRun(sourceCode);
+		ABI_CHECK(callContractFunction("ticketPrice()"), encodeArgs(u256(500)));
+	);
 }
 
 BOOST_AUTO_TEST_CASE(accessor_for_const_state_variable)

test/libsolidity/semanticTests/state_var_initialization.sol

@@ -0,0 +1,14 @@
+contract C {
+    uint public i = 1;
+    uint public k = 2;
+
+    constructor() public {
+        i = i + i;
+        k = k - i;
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// i() -> 2
+// k() -> 0