Merge pull request #2291 from ethereum/evm15

Allow different assembly types and target machines.

13 files changed, 207 insertions, 300 deletions

diff --git a/libsolidity/CMakeLists.txt b/libsolidity/CMakeLists.txt
index bcc47e5a..2342f0f9 100644
--- a/libsolidity/CMakeLists.txt
+++ b/libsolidity/CMakeLists.txt
@@ -7,10 +7,12 @@ aux_source_directory(formal SRC_LIST)
 aux_source_directory(interface SRC_LIST)
 aux_source_directory(parsing SRC_LIST)
 aux_source_directory(inlineasm SRC_LIST)
+# Until we have a clear separation, libjulia has to be included here
+aux_source_directory(../libjulia SRC_LIST)
 
 set(EXECUTABLE solidity)
 
-file(GLOB HEADERS "*/*.h") 
+file(GLOB HEADERS "*/*.h" "../libjulia/backends/evm/*")
 
 include_directories(BEFORE ..)
 add_library(${EXECUTABLE} ${SRC_LIST} ${HEADERS})
diff --git a/libsolidity/analysis/ReferencesResolver.cpp b/libsolidity/analysis/ReferencesResolver.cpp
index 9433976a..83ea17c7 100644
--- a/libsolidity/analysis/ReferencesResolver.cpp
+++ b/libsolidity/analysis/ReferencesResolver.cpp
@@ -166,8 +166,8 @@ bool ReferencesResolver::visit(InlineAssembly const& _inlineAssembly)
 	// The only purpose of this step is to fill the inline assembly annotation with
 	// external references.
 	ErrorList errorsIgnored;
-	assembly::ExternalIdentifierAccess::Resolver resolver =
-	[&](assembly::Identifier const& _identifier, assembly::IdentifierContext) {
+	julia::ExternalIdentifierAccess::Resolver resolver =
+	[&](assembly::Identifier const& _identifier, julia::IdentifierContext) {
 		auto declarations = m_resolver.nameFromCurrentScope(_identifier.name);
 		bool isSlot = boost::algorithm::ends_with(_identifier.name, "_slot");
 		bool isOffset = boost::algorithm::ends_with(_identifier.name, "_offset");
diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index 8161a3a1..ad22cc66 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -631,9 +631,9 @@ bool TypeChecker::visit(InlineAssembly const& _inlineAssembly)
 {
 	// External references have already been resolved in a prior stage and stored in the annotation.
 	// We run the resolve step again regardless.
-	assembly::ExternalIdentifierAccess::Resolver identifierAccess = [&](
+	julia::ExternalIdentifierAccess::Resolver identifierAccess = [&](
 		assembly::Identifier const& _identifier,
-		assembly::IdentifierContext _context
+		julia::IdentifierContext _context
 	)
 	{
 		auto ref = _inlineAssembly.annotation().externalReferences.find(&_identifier);
@@ -650,7 +650,7 @@ bool TypeChecker::visit(InlineAssembly const& _inlineAssembly)
 					typeError(_identifier.location, "The suffixes _offset and _slot can only be used on storage variables.");
 					return size_t(-1);
 				}
-				else if (_context != assembly::IdentifierContext::RValue)
+				else if (_context != julia::IdentifierContext::RValue)
 				{
 					typeError(_identifier.location, "Storage variables cannot be assigned to.");
 					return size_t(-1);
@@ -677,13 +677,13 @@ bool TypeChecker::visit(InlineAssembly const& _inlineAssembly)
 				return size_t(-1);
 			}
 		}
-		else if (_context == assembly::IdentifierContext::LValue)
+		else if (_context == julia::IdentifierContext::LValue)
 		{
 			typeError(_identifier.location, "Only local variables can be assigned to in inline assembly.");
 			return size_t(-1);
 		}
 
-		if (_context == assembly::IdentifierContext::RValue)
+		if (_context == julia::IdentifierContext::RValue)
 		{
 			solAssert(!!declaration->type(), "Type of declaration required but not yet determined.");
 			if (dynamic_cast<FunctionDefinition const*>(declaration))
diff --git a/libsolidity/codegen/CompilerContext.cpp b/libsolidity/codegen/CompilerContext.cpp
index 5c4f88c4..404a3af6 100644
--- a/libsolidity/codegen/CompilerContext.cpp
+++ b/libsolidity/codegen/CompilerContext.cpp
@@ -266,10 +266,10 @@ void CompilerContext::appendInlineAssembly(
 
 	int startStackHeight = stackHeight();
 
-	assembly::ExternalIdentifierAccess identifierAccess;
+	julia::ExternalIdentifierAccess identifierAccess;
 	identifierAccess.resolve = [&](
 		assembly::Identifier const& _identifier,
-		assembly::IdentifierContext
+		julia::IdentifierContext
 	)
 	{
 		auto it = std::find(_localVariables.begin(), _localVariables.end(), _identifier.name);
@@ -277,7 +277,7 @@ void CompilerContext::appendInlineAssembly(
 	};
 	identifierAccess.generateCode = [&](
 		assembly::Identifier const& _identifier,
-		assembly::IdentifierContext _context,
+		julia::IdentifierContext _context,
 		julia::AbstractAssembly& _assembly
 	)
 	{
@@ -285,14 +285,14 @@ void CompilerContext::appendInlineAssembly(
 		solAssert(it != _localVariables.end(), "");
 		int stackDepth = _localVariables.end() - it;
 		int stackDiff = _assembly.stackHeight() - startStackHeight + stackDepth;
-		if (_context == assembly::IdentifierContext::LValue)
+		if (_context == julia::IdentifierContext::LValue)
 			stackDiff -= 1;
 		if (stackDiff < 1 || stackDiff > 16)
 			BOOST_THROW_EXCEPTION(
 				CompilerError() <<
 				errinfo_comment("Stack too deep (" + to_string(stackDiff) + "), try removing local variables.")
 			);
-		if (_context == assembly::IdentifierContext::RValue)
+		if (_context == julia::IdentifierContext::RValue)
 			_assembly.appendInstruction(dupInstruction(stackDiff));
 		else
 		{
diff --git a/libsolidity/codegen/ContractCompiler.cpp b/libsolidity/codegen/ContractCompiler.cpp
index 41940e1a..e79bb6dc 100644
--- a/libsolidity/codegen/ContractCompiler.cpp
+++ b/libsolidity/codegen/ContractCompiler.cpp
@@ -522,21 +522,21 @@ bool ContractCompiler::visit(InlineAssembly const& _inlineAssembly)
 	ErrorList errors;
 	assembly::CodeGenerator codeGen(errors);
 	unsigned startStackHeight = m_context.stackHeight();
-	assembly::ExternalIdentifierAccess identifierAccess;
-	identifierAccess.resolve = [&](assembly::Identifier const& _identifier, assembly::IdentifierContext)
+	julia::ExternalIdentifierAccess identifierAccess;
+	identifierAccess.resolve = [&](assembly::Identifier const& _identifier, julia::IdentifierContext)
 	{
 		auto ref = _inlineAssembly.annotation().externalReferences.find(&_identifier);
 		if (ref == _inlineAssembly.annotation().externalReferences.end())
 			return size_t(-1);
 		return ref->second.valueSize;
 	};
-	identifierAccess.generateCode = [&](assembly::Identifier const& _identifier, assembly::IdentifierContext _context, julia::AbstractAssembly& _assembly)
+	identifierAccess.generateCode = [&](assembly::Identifier const& _identifier, julia::IdentifierContext _context, julia::AbstractAssembly& _assembly)
 	{
 		auto ref = _inlineAssembly.annotation().externalReferences.find(&_identifier);
 		solAssert(ref != _inlineAssembly.annotation().externalReferences.end(), "");
 		Declaration const* decl = ref->second.declaration;
 		solAssert(!!decl, "");
-		if (_context == assembly::IdentifierContext::RValue)
+		if (_context == julia::IdentifierContext::RValue)
 		{
 			int const depositBefore = _assembly.stackHeight();
 			solAssert(!!decl->type(), "Type of declaration required but not yet determined.");
diff --git a/libsolidity/inlineasm/AsmAnalysis.cpp b/libsolidity/inlineasm/AsmAnalysis.cpp
index d022ecf6..60caaa1d 100644
--- a/libsolidity/inlineasm/AsmAnalysis.cpp
+++ b/libsolidity/inlineasm/AsmAnalysis.cpp
@@ -41,7 +41,7 @@ using namespace dev::solidity::assembly;
 AsmAnalyzer::AsmAnalyzer(
 	AsmAnalysisInfo& _analysisInfo,
 	ErrorList& _errors,
-	ExternalIdentifierAccess::Resolver const& _resolver
+	julia::ExternalIdentifierAccess::Resolver const& _resolver
 ):
 	m_resolver(_resolver), m_info(_analysisInfo), m_errors(_errors)
 {
@@ -123,7 +123,7 @@ bool AsmAnalyzer::operator()(assembly::Identifier const& _identifier)
 	{
 		size_t stackSize(-1);
 		if (m_resolver)
-			stackSize = m_resolver(_identifier, IdentifierContext::RValue);
+			stackSize = m_resolver(_identifier, julia::IdentifierContext::RValue);
 		if (stackSize == size_t(-1))
 		{
 			// Only add an error message if the callback did not do it.
@@ -393,7 +393,7 @@ bool AsmAnalyzer::checkAssignment(assembly::Identifier const& _variable, size_t
 		variableSize = 1;
 	}
 	else if (m_resolver)
-		variableSize = m_resolver(_variable, IdentifierContext::LValue);
+		variableSize = m_resolver(_variable, julia::IdentifierContext::LValue);
 	if (variableSize == size_t(-1))
 	{
 		// Only add message if the callback did not.
diff --git a/libsolidity/inlineasm/AsmAnalysis.h b/libsolidity/inlineasm/AsmAnalysis.h
index 9f022b12..613abf38 100644
--- a/libsolidity/inlineasm/AsmAnalysis.h
+++ b/libsolidity/inlineasm/AsmAnalysis.h
@@ -64,7 +64,7 @@ public:
 	AsmAnalyzer(
 		AsmAnalysisInfo& _analysisInfo,
 		ErrorList& _errors,
-		ExternalIdentifierAccess::Resolver const& _resolver = ExternalIdentifierAccess::Resolver()
+		julia::ExternalIdentifierAccess::Resolver const& _resolver = julia::ExternalIdentifierAccess::Resolver()
 	);
 
 	bool analyze(assembly::Block const& _block);
@@ -94,7 +94,7 @@ private:
 	/// we enter the block.
 	int m_virtualVariablesInNextBlock = 0;
 	int m_stackHeight = 0;
-	ExternalIdentifierAccess::Resolver const& m_resolver;
+	julia::ExternalIdentifierAccess::Resolver const& m_resolver;
 	Scope* m_currentScope = nullptr;
 	AsmAnalysisInfo& m_info;
 	ErrorList& m_errors;
diff --git a/libsolidity/inlineasm/AsmCodeGen.cpp b/libsolidity/inlineasm/AsmCodeGen.cpp
index 5c66b125..6a44faac 100644
--- a/libsolidity/inlineasm/AsmCodeGen.cpp
+++ b/libsolidity/inlineasm/AsmCodeGen.cpp
@@ -32,7 +32,8 @@
 #include <libevmasm/SourceLocation.h>
 #include <libevmasm/Instruction.h>
 
-#include <libjulia/backends/AbstractAssembly.h>
+#include <libjulia/backends/evm/AbstractAssembly.h>
+#include <libjulia/backends/evm/EVMCodeTransform.h>
 
 #include <libdevcore/CommonIO.h>
 
@@ -48,15 +49,6 @@ using namespace dev;
 using namespace dev::solidity;
 using namespace dev::solidity::assembly;
 
-struct GeneratorState
-{
-	GeneratorState(ErrorList& _errors, AsmAnalysisInfo& _analysisInfo):
-		errors(_errors), info(_analysisInfo) {}
-
-	ErrorList& errors;
-	AsmAnalysisInfo info;
-};
-
 class EthAssemblyAdapter: public julia::AbstractAssembly
 {
 public:
@@ -107,254 +99,15 @@ private:
 	eth::Assembly& m_assembly;
 };
 
-class CodeTransform: public boost::static_visitor<>
-{
-public:
-	/// Create the code transformer which appends assembly to _state.assembly when called
-	/// with parsed assembly data.
-	/// @param _identifierAccess used to resolve identifiers external to the inline assembly
-	explicit CodeTransform(
-		GeneratorState& _state,
-		julia::AbstractAssembly& _assembly,
-		assembly::Block const& _block,
-		assembly::ExternalIdentifierAccess const& _identifierAccess = assembly::ExternalIdentifierAccess()
-	): CodeTransform(_state, _assembly, _block, _identifierAccess, _assembly.stackHeight())
-	{
-	}
-
-private:
-	CodeTransform(
-		GeneratorState& _state,
-		julia::AbstractAssembly& _assembly,
-		assembly::Block const& _block,
-		assembly::ExternalIdentifierAccess const& _identifierAccess,
-		int _initialStackHeight
-	):
-		m_state(_state),
-		m_assembly(_assembly),
-		m_scope(*m_state.info.scopes.at(&_block)),
-		m_identifierAccess(_identifierAccess),
-		m_initialStackHeight(_initialStackHeight)
-	{
-		int blockStartStackHeight = m_assembly.stackHeight();
-		std::for_each(_block.statements.begin(), _block.statements.end(), boost::apply_visitor(*this));
-
-		m_assembly.setSourceLocation(_block.location);
-
-		// pop variables
-		for (auto const& identifier: m_scope.identifiers)
-			if (identifier.second.type() == typeid(Scope::Variable))
-				m_assembly.appendInstruction(solidity::Instruction::POP);
-
-		int deposit = m_assembly.stackHeight() - blockStartStackHeight;
-		solAssert(deposit == 0, "Invalid stack height at end of block.");
-	}
-
-public:
-	void operator()(assembly::Instruction const& _instruction)
-	{
-		m_assembly.setSourceLocation(_instruction.location);
-		m_assembly.appendInstruction(_instruction.instruction);
-		checkStackHeight(&_instruction);
-	}
-	void operator()(assembly::Literal const& _literal)
-	{
-		m_assembly.setSourceLocation(_literal.location);
-		if (_literal.kind == assembly::LiteralKind::Number)
-			m_assembly.appendConstant(u256(_literal.value));
-		else if (_literal.kind == assembly::LiteralKind::Boolean)
-		{
-			if (_literal.value == "true")
-				m_assembly.appendConstant(u256(1));
-			else
-				m_assembly.appendConstant(u256(0));
-		}
-		else
-		{
-			solAssert(_literal.value.size() <= 32, "");
-			m_assembly.appendConstant(u256(h256(_literal.value, h256::FromBinary, h256::AlignLeft)));
-		}
-		checkStackHeight(&_literal);
-	}
-	void operator()(assembly::Identifier const& _identifier)
-	{
-		m_assembly.setSourceLocation(_identifier.location);
-		// First search internals, then externals.
-		if (m_scope.lookup(_identifier.name, Scope::NonconstVisitor(
-			[=](Scope::Variable& _var)
-			{
-				if (int heightDiff = variableHeightDiff(_var, _identifier.location, false))
-					m_assembly.appendInstruction(solidity::dupInstruction(heightDiff));
-				else
-					// Store something to balance the stack
-					m_assembly.appendConstant(u256(0));
-			},
-			[=](Scope::Label& _label)
-			{
-				assignLabelIdIfUnset(_label);
-				m_assembly.appendLabelReference(*_label.id);
-			},
-			[=](Scope::Function&)
-			{
-				solAssert(false, "Function not removed during desugaring.");
-			}
-		)))
-		{
-			return;
-		}
-		solAssert(
-			m_identifierAccess.generateCode,
-			"Identifier not found and no external access available."
-		);
-		m_identifierAccess.generateCode(_identifier, IdentifierContext::RValue, m_assembly);
-		checkStackHeight(&_identifier);
-	}
-	void operator()(FunctionalInstruction const& _instr)
-	{
-		for (auto it = _instr.arguments.rbegin(); it != _instr.arguments.rend(); ++it)
-		{
-			int height = m_assembly.stackHeight();
-			boost::apply_visitor(*this, *it);
-			expectDeposit(1, height);
-		}
-		(*this)(_instr.instruction);
-		checkStackHeight(&_instr);
-	}
-	void operator()(assembly::FunctionCall const&)
-	{
-		solAssert(false, "Function call not removed during desugaring phase.");
-	}
-	void operator()(Label const& _label)
-	{
-		m_assembly.setSourceLocation(_label.location);
-		solAssert(m_scope.identifiers.count(_label.name), "");
-		Scope::Label& label = boost::get<Scope::Label>(m_scope.identifiers.at(_label.name));
-		assignLabelIdIfUnset(label);
-		m_assembly.appendLabel(*label.id);
-		checkStackHeight(&_label);
-	}
-	void operator()(assembly::StackAssignment const& _assignment)
-	{
-		m_assembly.setSourceLocation(_assignment.location);
-		generateAssignment(_assignment.variableName, _assignment.location);
-		checkStackHeight(&_assignment);
-	}
-	void operator()(assembly::Assignment const& _assignment)
-	{
-		int height = m_assembly.stackHeight();
-		boost::apply_visitor(*this, *_assignment.value);
-		expectDeposit(1, height);
-		m_assembly.setSourceLocation(_assignment.location);
-		generateAssignment(_assignment.variableName, _assignment.location);
-		checkStackHeight(&_assignment);
-	}
-	void operator()(assembly::VariableDeclaration const& _varDecl)
-	{
-		int height = m_assembly.stackHeight();
-		int expectedItems = _varDecl.variables.size();
-		boost::apply_visitor(*this, *_varDecl.value);
-		expectDeposit(expectedItems, height);
-		for (auto const& variable: _varDecl.variables)
-		{
-			auto& var = boost::get<Scope::Variable>(m_scope.identifiers.at(variable.name));
-			var.stackHeight = height++;
-			var.active = true;
-		}
-	}
-	void operator()(assembly::Block const& _block)
-	{
-		CodeTransform(m_state, m_assembly, _block, m_identifierAccess, m_initialStackHeight);
-		checkStackHeight(&_block);
-	}
-	void operator()(assembly::Switch const&)
-	{
-		solAssert(false, "Switch not removed during desugaring phase.");
-	}
-	void operator()(assembly::FunctionDefinition const&)
-	{
-		solAssert(false, "Function definition not removed during desugaring phase.");
-	}
-
-private:
-	void generateAssignment(assembly::Identifier const& _variableName, SourceLocation const& _location)
-	{
-		auto var = m_scope.lookup(_variableName.name);
-		if (var)
-		{
-			Scope::Variable const& _var = boost::get<Scope::Variable>(*var);
-			if (int heightDiff = variableHeightDiff(_var, _location, true))
-				m_assembly.appendInstruction(solidity::swapInstruction(heightDiff - 1));
-			m_assembly.appendInstruction(solidity::Instruction::POP);
-		}
-		else
-		{
-			solAssert(
-				m_identifierAccess.generateCode,
-				"Identifier not found and no external access available."
-			);
-			m_identifierAccess.generateCode(_variableName, IdentifierContext::LValue, m_assembly);
-		}
-	}
-
-	/// Determines the stack height difference to the given variables. Automatically generates
-	/// errors if it is not yet in scope or the height difference is too large. Returns 0 on
-	/// errors and the (positive) stack height difference otherwise.
-	int variableHeightDiff(Scope::Variable const& _var, SourceLocation const& _location, bool _forSwap)
-	{
-		int heightDiff = m_assembly.stackHeight() - _var.stackHeight;
-		if (heightDiff <= (_forSwap ? 1 : 0) || heightDiff > (_forSwap ? 17 : 16))
-		{
-			//@TODO move this to analysis phase.
-			m_state.errors.push_back(make_shared<Error>(
-				Error::Type::TypeError,
-				"Variable inaccessible, too deep inside stack (" + boost::lexical_cast<string>(heightDiff) + ")",
-				_location
-			));
-			return 0;
-		}
-		else
-			return heightDiff;
-	}
-
-	void expectDeposit(int _deposit, int _oldHeight)
-	{
-		solAssert(m_assembly.stackHeight() == _oldHeight + _deposit, "Invalid stack deposit.");
-	}
-
-	void checkStackHeight(void const* _astElement)
-	{
-		solAssert(m_state.info.stackHeightInfo.count(_astElement), "Stack height for AST element not found.");
-		solAssert(
-			m_state.info.stackHeightInfo.at(_astElement) == m_assembly.stackHeight() - m_initialStackHeight,
-			"Stack height mismatch between analysis and code generation phase."
-		);
-	}
-
-	/// Assigns the label's id to a value taken from eth::Assembly if it has not yet been set.
-	void assignLabelIdIfUnset(Scope::Label& _label)
-	{
-		if (!_label.id)
-			_label.id.reset(m_assembly.newLabelId());
-	}
-
-
-	GeneratorState& m_state;
-	julia::AbstractAssembly& m_assembly;
-	Scope& m_scope;
-	ExternalIdentifierAccess m_identifierAccess;
-	int const m_initialStackHeight;
-};
-
 eth::Assembly assembly::CodeGenerator::assemble(
 	Block const& _parsedData,
 	AsmAnalysisInfo& _analysisInfo,
-	ExternalIdentifierAccess const& _identifierAccess
+	julia::ExternalIdentifierAccess const& _identifierAccess
 )
 {
 	eth::Assembly assembly;
-	GeneratorState state(m_errors, _analysisInfo);
 	EthAssemblyAdapter assemblyAdapter(assembly);
-	CodeTransform(state, assemblyAdapter, _parsedData, _identifierAccess);
+	julia::CodeTransform(m_errors, assemblyAdapter, _parsedData, _analysisInfo, _identifierAccess);
 	return assembly;
 }
 
@@ -362,10 +115,9 @@ void assembly::CodeGenerator::assemble(
 	Block const& _parsedData,
 	AsmAnalysisInfo& _analysisInfo,
 	eth::Assembly& _assembly,
-	ExternalIdentifierAccess const& _identifierAccess
+	julia::ExternalIdentifierAccess const& _identifierAccess
 )
 {
-	GeneratorState state(m_errors, _analysisInfo);
 	EthAssemblyAdapter assemblyAdapter(_assembly);
-	CodeTransform(state, assemblyAdapter, _parsedData, _identifierAccess);
+	julia::CodeTransform(m_errors, assemblyAdapter, _parsedData, _analysisInfo, _identifierAccess);
 }
diff --git a/libsolidity/inlineasm/AsmCodeGen.h b/libsolidity/inlineasm/AsmCodeGen.h
index e830e047..1b43d2f6 100644
--- a/libsolidity/inlineasm/AsmCodeGen.h
+++ b/libsolidity/inlineasm/AsmCodeGen.h
@@ -48,14 +48,14 @@ public:
 	eth::Assembly assemble(
 		Block const& _parsedData,
 		AsmAnalysisInfo& _analysisInfo,
-		ExternalIdentifierAccess const& _identifierAccess = ExternalIdentifierAccess()
+		julia::ExternalIdentifierAccess const& _identifierAccess = julia::ExternalIdentifierAccess()
 	);
 	/// Performs code generation and appends generated to to _assembly.
 	void assemble(
 		Block const& _parsedData,
 		AsmAnalysisInfo& _analysisInfo,
 		eth::Assembly& _assembly,
-		ExternalIdentifierAccess const& _identifierAccess = ExternalIdentifierAccess()
+		julia::ExternalIdentifierAccess const& _identifierAccess = julia::ExternalIdentifierAccess()
 	);
 
 private:
diff --git a/libsolidity/inlineasm/AsmStack.cpp b/libsolidity/inlineasm/AsmStack.cpp
index c2a7d8ea..2e63465f 100644
--- a/libsolidity/inlineasm/AsmStack.cpp
+++ b/libsolidity/inlineasm/AsmStack.cpp
@@ -42,7 +42,7 @@ using namespace dev::solidity::assembly;
 
 bool InlineAssemblyStack::parse(
 	shared_ptr<Scanner> const& _scanner,
-	ExternalIdentifierAccess::Resolver const& _resolver
+	julia::ExternalIdentifierAccess::Resolver const& _resolver
 )
 {
 	m_parserResult = make_shared<Block>();
@@ -73,7 +73,7 @@ eth::Assembly InlineAssemblyStack::assemble()
 bool InlineAssemblyStack::parseAndAssemble(
 	string const& _input,
 	eth::Assembly& _assembly,
-	ExternalIdentifierAccess const& _identifierAccess
+	julia::ExternalIdentifierAccess const& _identifierAccess
 )
 {
 	ErrorList errors;
diff --git a/libsolidity/inlineasm/AsmStack.h b/libsolidity/inlineasm/AsmStack.h
index e223ccc9..23072a88 100644
--- a/libsolidity/inlineasm/AsmStack.h
+++ b/libsolidity/inlineasm/AsmStack.h
@@ -24,7 +24,7 @@
 
 #include <libsolidity/interface/Exceptions.h>
 
-#include <libjulia/backends/AbstractAssembly.h>
+#include <libjulia/backends/evm/AbstractAssembly.h>
 
 #include <string>
 #include <functional>
@@ -43,23 +43,6 @@ namespace assembly
 struct Block;
 struct Identifier;
 
-enum class IdentifierContext { LValue, RValue };
-
-/// Object that is used to resolve references and generate code for access to identifiers external
-/// to inline assembly (not used in standalone assembly mode).
-struct ExternalIdentifierAccess
-{
-	using Resolver = std::function<size_t(assembly::Identifier const&, IdentifierContext)>;
-	/// Resolve a an external reference given by the identifier in the given context.
-	/// @returns the size of the value (number of stack slots) or size_t(-1) if not found.
-	Resolver resolve;
-	using CodeGenerator = std::function<void(assembly::Identifier const&, IdentifierContext, julia::AbstractAssembly&)>;
-	/// Generate code for retrieving the value (rvalue context) or storing the value (lvalue context)
-	/// of an identifier. The code should be appended to the assembly. In rvalue context, the value is supposed
-	/// to be put onto the stack, in lvalue context, the value is assumed to be at the top of the stack.
-	CodeGenerator generateCode;
-};
-
 class InlineAssemblyStack
 {
 public:
@@ -67,7 +50,7 @@ public:
 	/// @return false or error.
 	bool parse(
 		std::shared_ptr<Scanner> const& _scanner,
-		ExternalIdentifierAccess::Resolver const& _externalIdentifierResolver = ExternalIdentifierAccess::Resolver()
+		julia::ExternalIdentifierAccess::Resolver const& _externalIdentifierResolver = julia::ExternalIdentifierAccess::Resolver()
 	);
 	/// Converts the parser result back into a string form (not necessarily the same form
 	/// as the source form, but it should parse into the same parsed form again).
@@ -79,7 +62,7 @@ public:
 	bool parseAndAssemble(
 		std::string const& _input,
 		eth::Assembly& _assembly,
-		ExternalIdentifierAccess const& _identifierAccess = ExternalIdentifierAccess()
+		julia::ExternalIdentifierAccess const& _identifierAccess = julia::ExternalIdentifierAccess()
 	);
 
 	ErrorList const& errors() const { return m_errors; }
diff --git a/libsolidity/interface/AssemblyStack.cpp b/libsolidity/interface/AssemblyStack.cpp
new file mode 100644
index 00000000..c4bd63c4
--- /dev/null
+++ b/libsolidity/interface/AssemblyStack.cpp
@@ -0,0 +1,85 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Full assembly stack that can support EVM-assembly and JULIA as input and EVM, EVM1.5 and
+ * eWasm as output.
+ */
+
+
+#include <libsolidity/interface/AssemblyStack.h>
+
+#include <libsolidity/parsing/Scanner.h>
+#include <libsolidity/inlineasm/AsmPrinter.h>
+#include <libsolidity/inlineasm/AsmParser.h>
+#include <libsolidity/inlineasm/AsmAnalysis.h>
+#include <libsolidity/inlineasm/AsmCodeGen.h>
+
+#include <libevmasm/Assembly.h>
+
+using namespace std;
+using namespace dev;
+using namespace dev::solidity;
+
+
+Scanner const& AssemblyStack::scanner() const
+{
+	solAssert(m_scanner, "");
+	return *m_scanner;
+}
+
+bool AssemblyStack::parseAndAnalyze(std::string const& _sourceName, std::string const& _source)
+{
+	m_analysisSuccessful = false;
+	m_scanner = make_shared<Scanner>(CharStream(_source), _sourceName);
+	m_parserResult = assembly::Parser(m_errors, m_language == Language::JULIA).parse(m_scanner);
+	if (!m_errors.empty())
+		return false;
+	solAssert(m_parserResult, "");
+
+	m_analysisInfo = make_shared<assembly::AsmAnalysisInfo>();
+	assembly::AsmAnalyzer analyzer(*m_analysisInfo, m_errors);
+	m_analysisSuccessful = analyzer.analyze(*m_parserResult);
+	return m_analysisSuccessful;
+}
+
+eth::LinkerObject AssemblyStack::assemble(Machine _machine)
+{
+	solAssert(m_analysisSuccessful, "");
+	solAssert(m_parserResult, "");
+	solAssert(m_analysisInfo, "");
+
+	switch (_machine)
+	{
+	case Machine::EVM:
+	{
+		auto assembly = assembly::CodeGenerator(m_errors).assemble(*m_parserResult, *m_analysisInfo);
+		return assembly.assemble();
+	}
+	case Machine::EVM15:
+		solUnimplemented("EVM 1.5 backend is not yet implemented.");
+	case Machine::eWasm:
+		solUnimplemented("eWasm backend is not yet implemented.");
+	}
+	// unreachable
+	return eth::LinkerObject();
+}
+
+string AssemblyStack::print()
+{
+	solAssert(m_parserResult, "");
+	return assembly::AsmPrinter(m_language == Language::JULIA)(*m_parserResult);
+}
diff --git a/libsolidity/interface/AssemblyStack.h b/libsolidity/interface/AssemblyStack.h
new file mode 100644
index 00000000..40662ac3
--- /dev/null
+++ b/libsolidity/interface/AssemblyStack.h
@@ -0,0 +1,85 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Full assembly stack that can support EVM-assembly and JULIA as input and EVM, EVM1.5 and
+ * eWasm as output.
+ */
+
+#pragma once
+
+#include <libsolidity/interface/Exceptions.h>
+#include <libsolidity/inlineasm/AsmAnalysisInfo.h>
+#include <libevmasm/LinkerObject.h>
+
+#include <string>
+#include <memory>
+
+namespace dev
+{
+namespace solidity
+{
+class Scanner;
+namespace assembly
+{
+struct AsmAnalysisInfo;
+struct Block;
+}
+
+/*
+ * Full assembly stack that can support EVM-assembly and JULIA as input and EVM, EVM1.5 and
+ * eWasm as output.
+ */
+class AssemblyStack
+{
+public:
+	enum class Language { JULIA, Assembly };
+	enum class Machine { EVM, EVM15, eWasm };
+
+	explicit AssemblyStack(Language _language = Language::Assembly):
+		m_language(_language)
+	{}
+
+	/// @returns the scanner used during parsing
+	Scanner const& scanner() const;
+
+	/// Runs parsing and analysis steps, returns false if input cannot be assembled.
+	/// Multiple calls overwrite the previous state.
+	bool parseAndAnalyze(std::string const& _sourceName, std::string const& _source);
+
+	/// Run the assembly step (should only be called after parseAndAnalyze).
+	eth::LinkerObject assemble(Machine _machine);
+
+	/// @returns the errors generated during parsing, analysis (and potentially assembly).
+	ErrorList const& errors() const { return m_errors; }
+
+	/// Pretty-print the input after having parsed it.
+	std::string print();
+
+private:
+
+	Language m_language = Language::Assembly;
+
+	std::shared_ptr<Scanner> m_scanner;
+
+	bool m_analysisSuccessful = false;
+	std::shared_ptr<assembly::Block> m_parserResult;
+	std::shared_ptr<assembly::AsmAnalysisInfo> m_analysisInfo;
+	ErrorList m_errors;
+};
+
+}
+}