Order yul subobjects by order of reference.

Co-authored-by: Kamil Śliwak <kamil.sliwak@codepoets.it>

Changelog.md

@@ -19,6 +19,7 @@ Bugfixes:
  * SMTChecker: Fix formatting of unary minus expressions in invariants.
  * SMTChecker: Fix internal compiler error when reporting proved targets for BMC engine.
  * TypeChecker: Fix segfault when assigning nested tuple to tuple.
+ * Yul IR Code Generation: Deterministic order of Yul subobjects.
  * Yul Optimizer: Name simplification could lead to forbidden identifiers with a leading and/or trailing dot, e.g., ``x._`` would get simplified into ``x.``.
  * Yul Parser: Fix segfault when parsing very long location comments.
 

libsolidity/codegen/ir/IRGenerationContext.h

@@ -143,7 +143,8 @@ class IRGenerationContext
 
 	RevertStrings revertStrings() const { return m_revertStrings; }
 
-	std::set<ContractDefinition const*, ASTNode::CompareByID>& subObjectsCreated() { return m_subObjects; }
+	util::UniqueVector<ContractDefinition const*> const& subObjectsCreated() const { return m_subObjects; }
+	void addSubObject(ContractDefinition const* _contractDefinition) { m_subObjects.pushBack(_contractDefinition); }
 
 	bool memoryUnsafeInlineAssemblySeen() const { return m_memoryUnsafeInlineAssemblySeen; }
 	void setMemoryUnsafeInlineAssemblySeen() { m_memoryUnsafeInlineAssemblySeen = true; }
@@ -195,7 +196,7 @@ class IRGenerationContext
 	/// It will fail at runtime but the code must still compile.
 	InternalDispatchMap m_internalDispatchMap;
 
-	std::set<ContractDefinition const*, ASTNode::CompareByID> m_subObjects;
+	util::UniqueVector<ContractDefinition const*> m_subObjects;
 
 	langutil::DebugInfoSelection m_debugInfoSelection = {};
 	langutil::CharStreamProvider const* m_soliditySourceProvider = nullptr;

libsolidity/codegen/ir/IRGenerator.cpp

@@ -101,10 +101,10 @@ std::string IRGenerator::generate(
 	std::map<ContractDefinition const*, std::string_view const> const& _otherYulSources
 )
 {
-	auto subObjectSources = [&_otherYulSources](std::set<ContractDefinition const*, ASTNode::CompareByID> const& subObjects) -> std::string
+	auto subObjectSources = [&_otherYulSources](UniqueVector<ContractDefinition const*> const& _subObjects) -> std::string
 	{
 		std::string subObjectsSources;
-		for (ContractDefinition const* subObject: subObjects)
+		for (ContractDefinition const* subObject: _subObjects)
 			subObjectsSources += _otherYulSources.at(subObject);
 		return subObjectsSources;
 	};

libsolidity/codegen/ir/IRGeneratorForStatements.cpp

@@ -1559,7 +1559,7 @@ void IRGeneratorForStatements::endVisit(FunctionCall const& _functionCall)
 
 		ContractDefinition const* contract =
 			&dynamic_cast<ContractType const&>(*functionType->returnParameterTypes().front()).contractDefinition();
-		m_context.subObjectsCreated().insert(contract);
+		m_context.addSubObject(contract);
 
 		Whiskers t(R"(let <memPos> := <allocateUnbounded>()
 			let <memEnd> := add(<memPos>, datasize("<object>"))
@@ -1947,7 +1947,7 @@ void IRGeneratorForStatements::endVisit(MemberAccess const& _memberAccess)
 			auto const& contractType = dynamic_cast<ContractType const&>(*arg);
 			solAssert(!contractType.isSuper());
 			ContractDefinition const& contract = contractType.contractDefinition();
-			m_context.subObjectsCreated().insert(&contract);
+			m_context.addSubObject(&contract);
 			appendCode() << Whiskers(R"(
 				let <size> := datasize("<objectName>")
 				let <result> := <allocationFunction>(add(<size>, 32))