4 files changed, 81 insertions, 0 deletions

diff --git a/libsolidity/analysis/ReferencesResolver.cpp b/libsolidity/analysis/ReferencesResolver.cpp
index ca002f58..d7542bf3 100644
--- a/libsolidity/analysis/ReferencesResolver.cpp
+++ b/libsolidity/analysis/ReferencesResolver.cpp
@@ -25,6 +25,8 @@
 #include <libsolidity/analysis/NameAndTypeResolver.h>
 #include <libsolidity/interface/Exceptions.h>
 #include <libsolidity/analysis/ConstantEvaluator.h>
+#include <libsolidity/inlineasm/AsmCodeGen.h>
+#include <libsolidity/inlineasm/AsmData.h>
 
 using namespace std;
 using namespace dev;
@@ -112,6 +114,26 @@ void ReferencesResolver::endVisit(ArrayTypeName const& _typeName)
 		_typeName.annotation().type = make_shared<ArrayType>(DataLocation::Storage, baseType);
 }
 
+bool ReferencesResolver::visit(InlineAssembly const& _inlineAssembly)
+{
+	// We need to perform a full code generation pass here as inline assembly does not distinguish
+	// reference resolution and code generation.
+	// Errors created in this stage are completely ignored because we do not yet know
+	// the type and size of external identifiers, which would result in false errors.
+	ErrorList errorsIgnored;
+	assembly::CodeGenerator codeGen(_inlineAssembly.operations(), errorsIgnored);
+	codeGen.typeCheck([&](assembly::Identifier const& _identifier, eth::Assembly&, assembly::CodeGenerator::IdentifierContext) {
+		auto declarations = m_resolver.nameFromCurrentScope(_identifier.name);
+		if (declarations.size() != 1)
+			return false;
+		_inlineAssembly.annotation().externalReferences[&_identifier] = declarations.front();
+		// At this stage we neither know the code to generate nor the stack size of the identifier,
+		// so we do not modify assembly.
+		return true;
+	});
+	return false;
+}
+
 bool ReferencesResolver::visit(Return const& _return)
 {
 	_return.annotation().functionReturnParameters = m_returnParameters;
diff --git a/libsolidity/analysis/ReferencesResolver.h b/libsolidity/analysis/ReferencesResolver.h
index a2d71dc3..1986b2bb 100644
--- a/libsolidity/analysis/ReferencesResolver.h
+++ b/libsolidity/analysis/ReferencesResolver.h
@@ -64,6 +64,7 @@ private:
 	virtual void endVisit(UserDefinedTypeName const& _typeName) override;
 	virtual void endVisit(Mapping const& _typeName) override;
 	virtual void endVisit(ArrayTypeName const& _typeName) override;
+	virtual bool visit(InlineAssembly const& _inlineAssembly) override;
 	virtual bool visit(Return const& _return) override;
 	virtual void endVisit(VariableDeclaration const& _variable) override;
 
diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index 44f4629b..c63b6b5a 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -24,6 +24,8 @@
 #include <memory>
 #include <boost/range/adaptor/reversed.hpp>
 #include <libsolidity/ast/AST.h>
+#include <libevmasm/Assembly.h> // needed for inline assembly
+#include <libsolidity/inlineasm/AsmCodeGen.h>
 
 using namespace std;
 using namespace dev;
@@ -547,6 +549,61 @@ bool TypeChecker::visit(EventDefinition const& _eventDef)
 	return false;
 }
 
+bool TypeChecker::visit(InlineAssembly const& _inlineAssembly)
+{
+	// Inline assembly does not have its own type-checking phase, so we just run the
+	// code-generator and see whether it produces any errors.
+	// External references have already been resolved in a prior stage and stored in the annotation.
+	assembly::CodeGenerator codeGen(_inlineAssembly.operations(), m_errors);
+	codeGen.typeCheck([&](assembly::Identifier const& _identifier, eth::Assembly& _assembly, assembly::CodeGenerator::IdentifierContext _context) {
+		auto ref = _inlineAssembly.annotation().externalReferences.find(&_identifier);
+		if (ref == _inlineAssembly.annotation().externalReferences.end())
+			return false;
+		Declaration const* declaration = ref->second;
+		solAssert(!!declaration, "");
+		if (_context == assembly::CodeGenerator::IdentifierContext::RValue)
+		{
+			solAssert(!!declaration->type(), "Type of declaration required but not yet determined.");
+			unsigned pushes = 0;
+			if (dynamic_cast<FunctionDefinition const*>(declaration))
+				pushes = 1;
+			else if (auto var = dynamic_cast<VariableDeclaration const*>(declaration))
+			{
+				if (var->isConstant())
+					fatalTypeError(SourceLocation(), "Constant variables not yet implemented for inline assembly.");
+				if (var->isLocalVariable())
+					pushes = var->type()->sizeOnStack();
+				else if (var->type()->isValueType())
+					pushes = 1;
+				else
+					pushes = 2; // slot number, intra slot offset
+			}
+			else if (auto contract = dynamic_cast<ContractDefinition const*>(declaration))
+			{
+				if (!contract->isLibrary())
+					return false;
+				pushes = 1;
+			}
+			for (unsigned i = 0; i < pushes; ++i)
+				_assembly.append(u256(0)); // just to verify the stack height
+		}
+		else
+		{
+			// lvalue context
+			if (auto varDecl = dynamic_cast<VariableDeclaration const*>(declaration))
+			{
+				if (!varDecl->isLocalVariable())
+					return false; // only local variables are inline-assemlby lvalues
+				for (unsigned i = 0; i < declaration->type()->sizeOnStack(); ++i)
+					_assembly.append(eth::Instruction::POP); // remove value just to verify the stack height
+			}
+			else
+				return false;
+		}
+		return true;
+	});
+	return false;
+}
 
 bool TypeChecker::visit(IfStatement const& _ifStatement)
 {
diff --git a/libsolidity/analysis/TypeChecker.h b/libsolidity/analysis/TypeChecker.h
index b884db49..48f8285a 100644
--- a/libsolidity/analysis/TypeChecker.h
+++ b/libsolidity/analysis/TypeChecker.h
@@ -84,6 +84,7 @@ private:
 	/// case this is a base constructor call.
 	void visitManually(ModifierInvocation const& _modifier, std::vector<ContractDefinition const*> const& _bases);
 	virtual bool visit(EventDefinition const& _eventDef) override;
+	virtual bool visit(InlineAssembly const& _inlineAssembly) override;
 	virtual bool visit(IfStatement const& _ifStatement) override;
 	virtual bool visit(WhileStatement const& _whileStatement) override;
 	virtual bool visit(ForStatement const& _forStatement) override;