Pass "optimize stack allocation" flag down to the stack compressor.

libsolidity/codegen/CompilerContext.cpp

@@ -428,6 +428,7 @@ void CompilerContext::appendInlineAssembly(
 			yul::EVMDialect::strictAssemblyForEVM(m_evmVersion),
 			*parserResult,
 			analysisInfo,
+			_optimiserSettings.optimizeStackAllocation,
 			externallyUsedIdentifiers
 		);
 		analysisInfo = yul::AsmAnalysisInfo{};

libyul/AssemblyStack.cpp

@@ -135,7 +135,10 @@ void AssemblyStack::optimize(Object& _object)
 	for (auto& subNode: _object.subObjects)
 		if (auto subObject = dynamic_cast<Object*>(subNode.get()))
 			optimize(*subObject);
-	OptimiserSuite::run(languageToDialect(m_language, m_evmVersion), *_object.code, *_object.analysisInfo);
+	// TODO: Store this as setting - it should be the same as the flag passed to
+	// ::assemble(...)
+	bool optimizeStackAllocation = false;
+	OptimiserSuite::run(languageToDialect(m_language, m_evmVersion), *_object.code, *_object.analysisInfo, optimizeStackAllocation);
 }
 
 MachineAssemblyObject AssemblyStack::assemble(Machine _machine, bool _optimize) const

libyul/CompilabilityChecker.cpp

@@ -33,7 +33,11 @@ using namespace yul;
 using namespace dev;
 using namespace dev::solidity;
 
-std::map<YulString, int> CompilabilityChecker::run(std::shared_ptr<Dialect> _dialect, Block const& _ast)
+map<YulString, int> CompilabilityChecker::run(
+	shared_ptr<Dialect> _dialect,
+	Block const& _ast,
+	bool _optimizeStackAllocation
+)
 {
 	if (_dialect->flavour == AsmFlavour::Yul)
 		return {};
@@ -43,12 +47,11 @@ std::map<YulString, int> CompilabilityChecker::run(std::shared_ptr<Dialect> _dia
 	solAssert(dynamic_cast<EVMDialect const*>(_dialect.get()), "");
 	shared_ptr<NoOutputEVMDialect> noOutputDialect = make_shared<NoOutputEVMDialect>(dynamic_pointer_cast<EVMDialect>(_dialect));
 
-	bool optimize = true;
 	yul::AsmAnalysisInfo analysisInfo =
 		yul::AsmAnalyzer::analyzeStrictAssertCorrect(noOutputDialect, _ast);
 
 	NoOutputAssembly assembly;
-	CodeTransform transform(assembly, analysisInfo, _ast, *noOutputDialect, optimize);
+	CodeTransform transform(assembly, analysisInfo, _ast, *noOutputDialect, _optimizeStackAllocation);
 	try
 	{
 		transform(_ast);

libyul/CompilabilityChecker.h

@@ -39,7 +39,11 @@ namespace yul
 class CompilabilityChecker
 {
 public:
-	static std::map<YulString, int> run(std::shared_ptr<Dialect> _dialect, Block const& _ast);
+	static std::map<YulString, int> run(
+		std::shared_ptr<Dialect> _dialect,
+		Block const& _ast,
+		bool _optimizeStackAllocation
+	);
 };
 
 }

libyul/optimiser/StackCompressor.cpp

@@ -74,15 +74,15 @@ void eliminateVariables(shared_ptr<Dialect> const& _dialect, ASTNode& _node, siz
 
 }
 
-bool StackCompressor::run(shared_ptr<Dialect> const& _dialect, Block& _ast)
+bool StackCompressor::run(shared_ptr<Dialect> const& _dialect, Block& _ast, bool _optimizeStackAllocation)
 {
 	yulAssert(
 		_ast.statements.size() > 0 && _ast.statements.at(0).type() == typeid(Block),
 		"Need to run the function grouper before the stack compressor."
 	);
-	for (size_t iterations = 0; iterations < 4; iterations++)
+	for (size_t iterations = 0; iterations < 6; iterations++)
 	{
-		map<YulString, int> stackSurplus = CompilabilityChecker::run(_dialect, _ast);
+		map<YulString, int> stackSurplus = CompilabilityChecker::run(_dialect, _ast, _optimizeStackAllocation);
 		if (stackSurplus.empty())
 			return true;
 

libyul/optimiser/StackCompressor.h

@@ -41,7 +41,7 @@ class StackCompressor
 public:
 	/// Try to remove local variables until the AST is compilable.
 	/// @returns true if it was successful.
-	static bool run(std::shared_ptr<Dialect> const& _dialect, Block& _ast);
+	static bool run(std::shared_ptr<Dialect> const& _dialect, Block& _ast, bool _optimizeStackAllocation);
 };
 
 }

libyul/optimiser/Suite.cpp

@@ -59,6 +59,7 @@ void OptimiserSuite::run(
 	shared_ptr<Dialect> const& _dialect,
 	Block& _ast,
 	AsmAnalysisInfo const& _analysisInfo,
+	bool _optimizeStackAllocation,
 	set<YulString> const& _externallyUsedIdentifiers
 )
 {
@@ -185,7 +186,7 @@ void OptimiserSuite::run(
 	UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 
 	FunctionGrouper{}(ast);
-	StackCompressor::run(_dialect, ast);
+	solAssert(StackCompressor::run(_dialect, ast, _optimizeStackAllocation), "");
 	BlockFlattener{}(ast);
 
 	VarNameCleaner{ast, *_dialect, reservedIdentifiers}(ast);

libyul/optimiser/Suite.h

@@ -42,6 +42,7 @@ public:
 		std::shared_ptr<Dialect> const& _dialect,
 		Block& _ast,
 		AsmAnalysisInfo const& _analysisInfo,
+		bool _optimizeStackAllocation,
 		std::set<YulString> const& _externallyUsedIdentifiers = {}
 	);
 };

test/libyul/CompilabilityChecker.cpp

@@ -39,7 +39,7 @@ string check(string const& _input)
 {
 	shared_ptr<Block> ast = yul::test::parse(_input, false).first;
 	BOOST_REQUIRE(ast);
-	map<YulString, int> functions = CompilabilityChecker::run(EVMDialect::strictAssemblyForEVM(dev::test::Options::get().evmVersion()), *ast);
+	map<YulString, int> functions = CompilabilityChecker::run(EVMDialect::strictAssemblyForEVM(dev::test::Options::get().evmVersion()), *ast, true);
 	string out;
 	for (auto const& function: functions)
 		out += function.first.str() + ": " + to_string(function.second) + " ";

test/libyul/YulOptimizerTest.cpp

@@ -247,11 +247,11 @@ bool YulOptimizerTest::run(ostream& _stream, string const& _linePrefix, bool con
 	{
 		disambiguate();
 		(FunctionGrouper{})(*m_ast);
-		StackCompressor::run(m_dialect, *m_ast);
+		StackCompressor::run(m_dialect, *m_ast, true);
 		(BlockFlattener{})(*m_ast);
 	}
 	else if (m_optimizerStep == "fullSuite")
-		OptimiserSuite::run(m_dialect, *m_ast, *m_analysisInfo);
+		OptimiserSuite::run(m_dialect, *m_ast, *m_analysisInfo, true);
 	else
 	{
 		AnsiColorized(_stream, _formatted, {formatting::BOLD, formatting::RED}) << _linePrefix << "Invalid optimizer step: " << m_optimizerStep << endl;

test/tools/yulopti.cpp

@@ -198,7 +198,7 @@ public:
 				SSAReverser::run(*m_ast);
 				break;
 			case 'p':
-				StackCompressor::run(m_dialect, *m_ast);
+				StackCompressor::run(m_dialect, *m_ast, true);
 				break;
 			default:
 				cout << "Unknown option." << endl;