Named assembly labels.

13 files changed, 108 insertions, 28 deletions

diff --git a/libevmasm/Assembly.cpp b/libevmasm/Assembly.cpp
index 6b4bb52b..31857c09 100644
--- a/libevmasm/Assembly.cpp
+++ b/libevmasm/Assembly.cpp
@@ -49,6 +49,8 @@ void Assembly::append(Assembly const& _a)
 	}
 	m_deposit = newDeposit;
 	m_usedTags += _a.m_usedTags;
+	// This does not transfer the names of named tags on purpose. The tags themselves are
+	// transferred, but their names are only available inside the assembly.
 	for (auto const& i: _a.m_data)
 		m_data.insert(i);
 	for (auto const& i: _a.m_strings)
@@ -326,6 +328,14 @@ AssemblyItem const& Assembly::append(AssemblyItem const& _i)
 	return back();
 }
 
+AssemblyItem Assembly::namedTag(string const& _name)
+{
+	assertThrow(!_name.empty(), AssemblyException, "");
+	if (!m_namedTags.count(_name))
+		m_namedTags[_name] = size_t(newTag().data());
+	return AssemblyItem(Tag, m_namedTags.at(_name));
+}
+
 AssemblyItem Assembly::newPushLibraryAddress(string const& _identifier)
 {
 	h256 h(dev::keccak256(_identifier));
@@ -581,6 +591,7 @@ LinkerObject const& Assembly::assemble() const
 			assertThrow(i.data() != 0, AssemblyException, "");
 			assertThrow(i.splitForeignPushTag().first == size_t(-1), AssemblyException, "Foreign tag.");
 			assertThrow(ret.bytecode.size() < 0xffffffffL, AssemblyException, "Tag too large.");
+			assertThrow(m_tagPositionsInBytecode[size_t(i.data())] == size_t(-1), AssemblyException, "Duplicate tag position.");
 			m_tagPositionsInBytecode[size_t(i.data())] = ret.bytecode.size();
 			ret.bytecode.push_back((byte)Instruction::JUMPDEST);
 			break;
diff --git a/libevmasm/Assembly.h b/libevmasm/Assembly.h
index cbdd71bc..885192e4 100644
--- a/libevmasm/Assembly.h
+++ b/libevmasm/Assembly.h
@@ -47,6 +47,8 @@ public:
 
 	AssemblyItem newTag() { return AssemblyItem(Tag, m_usedTags++); }
 	AssemblyItem newPushTag() { return AssemblyItem(PushTag, m_usedTags++); }
+	/// Returns a tag identified by the given name. Creates it if it does not yet exist.
+	AssemblyItem namedTag(std::string const& _name);
 	AssemblyItem newData(bytes const& _data) { h256 h(dev::keccak256(asString(_data))); m_data[h] = _data; return AssemblyItem(PushData, h); }
 	AssemblyItem newSub(AssemblyPointer const& _sub) { m_subs.push_back(_sub); return AssemblyItem(PushSub, m_subs.size() - 1); }
 	Assembly const& sub(size_t _sub) const { return *m_subs.at(_sub); }
@@ -150,6 +152,7 @@ private:
 protected:
 	/// 0 is reserved for exception
 	unsigned m_usedTags = 1;
+	std::map<std::string, size_t> m_namedTags;
 	AssemblyItems m_items;
 	std::map<h256, bytes> m_data;
 	/// Data that is appended to the very end of the contract.
diff --git a/libjulia/backends/evm/AbstractAssembly.h b/libjulia/backends/evm/AbstractAssembly.h
index cfc9b8a5..8e90a912 100644
--- a/libjulia/backends/evm/AbstractAssembly.h
+++ b/libjulia/backends/evm/AbstractAssembly.h
@@ -66,6 +66,8 @@ public:
 	virtual void appendLabelReference(LabelID _labelId) = 0;
 	/// Generate a new unique label.
 	virtual LabelID newLabelId() = 0;
+	/// Returns a label identified by the given name. Creates it if it does not yet exist.
+	virtual LabelID namedLabel(std::string const& _name) = 0;
 	/// Append a reference to a to-be-linked symobl.
 	/// Currently, we assume that the value is always a 20 byte number.
 	virtual void appendLinkerSymbol(std::string const& _name) = 0;
diff --git a/libjulia/backends/evm/EVMAssembly.cpp b/libjulia/backends/evm/EVMAssembly.cpp
index 173d5e93..1d499b20 100644
--- a/libjulia/backends/evm/EVMAssembly.cpp
+++ b/libjulia/backends/evm/EVMAssembly.cpp
@@ -77,6 +77,14 @@ EVMAssembly::LabelID EVMAssembly::newLabelId()
 	return m_nextLabelId++;
 }
 
+AbstractAssembly::LabelID EVMAssembly::namedLabel(string const& _name)
+{
+	solAssert(!_name.empty(), "");
+	if (!m_namedLabels.count(_name))
+		m_namedLabels[_name] = newLabelId();
+	return m_namedLabels[_name];
+}
+
 void EVMAssembly::appendLinkerSymbol(string const&)
 {
 	solAssert(false, "Linker symbols not yet implemented.");
diff --git a/libjulia/backends/evm/EVMAssembly.h b/libjulia/backends/evm/EVMAssembly.h
index 69585822..593cee6a 100644
--- a/libjulia/backends/evm/EVMAssembly.h
+++ b/libjulia/backends/evm/EVMAssembly.h
@@ -52,6 +52,8 @@ public:
 	virtual void appendLabelReference(LabelID _labelId) override;
 	/// Generate a new unique label.
 	virtual LabelID newLabelId() override;
+	/// Returns a label identified by the given name. Creates it if it does not yet exist.
+	virtual LabelID namedLabel(std::string const& _name) override;
 	/// Append a reference to a to-be-linked symobl.
 	/// Currently, we assume that the value is always a 20 byte number.
 	virtual void appendLinkerSymbol(std::string const& _name) override;
@@ -85,6 +87,7 @@ private:
 	LabelID m_nextLabelId = 0;
 	int m_stackHeight = 0;
 	bytes m_bytecode;
+	std::map<std::string, LabelID> m_namedLabels;
 	std::map<LabelID, size_t> m_labelPositions;
 	std::map<size_t, LabelID> m_labelReferences;
 	std::vector<size_t> m_assemblySizePositions;
diff --git a/libjulia/backends/evm/EVMCodeTransform.cpp b/libjulia/backends/evm/EVMCodeTransform.cpp
index 704aa3c1..e0b11cf3 100644
--- a/libjulia/backends/evm/EVMCodeTransform.cpp
+++ b/libjulia/backends/evm/EVMCodeTransform.cpp
@@ -108,10 +108,10 @@ void CodeTransform::operator()(FunctionCall const& _call)
 		visitExpression(arg);
 	m_assembly.setSourceLocation(_call.location);
 	if (m_evm15)
-		m_assembly.appendJumpsub(functionEntryID(*function), function->arguments.size(), function->returns.size());
+		m_assembly.appendJumpsub(functionEntryID(_call.functionName.name, *function), function->arguments.size(), function->returns.size());
 	else
 	{
-		m_assembly.appendJumpTo(functionEntryID(*function), function->returns.size() - function->arguments.size() - 1);
+		m_assembly.appendJumpTo(functionEntryID(_call.functionName.name, *function), function->returns.size() - function->arguments.size() - 1);
 		m_assembly.appendLabel(returnLabel);
 		m_stackAdjustment--;
 	}
@@ -286,12 +286,12 @@ void CodeTransform::operator()(FunctionDefinition const& _function)
 	if (m_evm15)
 	{
 		m_assembly.appendJumpTo(afterFunction, -stackHeightBefore);
-		m_assembly.appendBeginsub(functionEntryID(function), _function.arguments.size());
+		m_assembly.appendBeginsub(functionEntryID(_function.name, function), _function.arguments.size());
 	}
 	else
 	{
 		m_assembly.appendJumpTo(afterFunction, -stackHeightBefore + height);
-		m_assembly.appendLabel(functionEntryID(function));
+		m_assembly.appendLabel(functionEntryID(_function.name, function));
 	}
 	m_stackAdjustment += localStackAdjustment;
 
@@ -303,8 +303,16 @@ void CodeTransform::operator()(FunctionDefinition const& _function)
 		m_assembly.appendConstant(u256(0));
 	}
 
-	CodeTransform(m_assembly, m_info, m_julia, m_evm15, m_identifierAccess, localStackAdjustment, m_context)
-		(_function.body);
+	CodeTransform(
+		m_assembly,
+		m_info,
+		m_julia,
+		m_evm15,
+		m_identifierAccess,
+		m_useNamedLabelsForFunctions,
+		localStackAdjustment,
+		m_context
+	)(_function.body);
 
 	{
 		// The stack layout here is:
@@ -421,10 +429,16 @@ AbstractAssembly::LabelID CodeTransform::labelID(Scope::Label const& _label)
 	return m_context->labelIDs[&_label];
 }
 
-AbstractAssembly::LabelID CodeTransform::functionEntryID(Scope::Function const& _function)
+AbstractAssembly::LabelID CodeTransform::functionEntryID(string const& _name, Scope::Function const& _function)
 {
 	if (!m_context->functionEntryIDs.count(&_function))
-		m_context->functionEntryIDs[&_function] = m_assembly.newLabelId();
+	{
+		AbstractAssembly::LabelID id =
+			m_useNamedLabelsForFunctions ?
+			m_assembly.namedLabel(_name) :
+			m_assembly.newLabelId();
+		m_context->functionEntryIDs[&_function] = id;
+	}
 	return m_context->functionEntryIDs[&_function];
 }
 
diff --git a/libjulia/backends/evm/EVMCodeTransform.h b/libjulia/backends/evm/EVMCodeTransform.h
index cd452c5b..2c0fd10c 100644
--- a/libjulia/backends/evm/EVMCodeTransform.h
+++ b/libjulia/backends/evm/EVMCodeTransform.h
@@ -50,13 +50,15 @@ public:
 		solidity::assembly::AsmAnalysisInfo& _analysisInfo,
 		bool _julia = false,
 		bool _evm15 = false,
-		ExternalIdentifierAccess const& _identifierAccess = ExternalIdentifierAccess()
+		ExternalIdentifierAccess const& _identifierAccess = ExternalIdentifierAccess(),
+		bool _useNamedLabelsForFunctions = false
 	): CodeTransform(
 		_assembly,
 		_analysisInfo,
 		_julia,
 		_evm15,
 		_identifierAccess,
+		_useNamedLabelsForFunctions,
 		_assembly.stackHeight(),
 		std::make_shared<Context>()
 	)
@@ -78,6 +80,7 @@ protected:
 		bool _julia,
 		bool _evm15,
 		ExternalIdentifierAccess const& _identifierAccess,
+		bool _useNamedLabelsForFunctions,
 		int _stackAdjustment,
 		std::shared_ptr<Context> _context
 	):
@@ -85,6 +88,7 @@ protected:
 		m_info(_analysisInfo),
 		m_julia(_julia),
 		m_evm15(_evm15),
+		m_useNamedLabelsForFunctions(_useNamedLabelsForFunctions),
 		m_identifierAccess(_identifierAccess),
 		m_stackAdjustment(_stackAdjustment),
 		m_context(_context)
@@ -110,7 +114,7 @@ private:
 	/// @returns the label ID corresponding to the given label, allocating a new one if
 	/// necessary.
 	AbstractAssembly::LabelID labelID(solidity::assembly::Scope::Label const& _label);
-	AbstractAssembly::LabelID functionEntryID(solidity::assembly::Scope::Function const& _function);
+	AbstractAssembly::LabelID functionEntryID(std::string const& _name, solidity::assembly::Scope::Function const& _function);
 	/// Generates code for an expression that is supposed to return a single value.
 	void visitExpression(solidity::assembly::Statement const& _expression);
 
@@ -136,6 +140,7 @@ private:
 	solidity::assembly::Scope* m_scope = nullptr;
 	bool m_julia = false;
 	bool m_evm15 = false;
+	bool m_useNamedLabelsForFunctions = false;
 	ExternalIdentifierAccess m_identifierAccess;
 	/// Adjustment between the stack height as determined during the analysis phase
 	/// and the stack height in the assembly. This is caused by an initial stack being present
diff --git a/libsolidity/codegen/CompilerContext.cpp b/libsolidity/codegen/CompilerContext.cpp
index ed780d0b..5a77162e 100644
--- a/libsolidity/codegen/CompilerContext.cpp
+++ b/libsolidity/codegen/CompilerContext.cpp
@@ -266,19 +266,9 @@ void CompilerContext::resetVisitedNodes(ASTNode const* _node)
 void CompilerContext::appendInlineAssembly(
 	string const& _assembly,
 	vector<string> const& _localVariables,
-	map<string, string> const& _replacements
+	bool _system
 )
 {
-	string replacedAssembly;
-	string const* assembly = &_assembly;
-	if (!_replacements.empty())
-	{
-		replacedAssembly = _assembly;
-		for (auto const& replacement: _replacements)
-			replacedAssembly = boost::algorithm::replace_all_copy(replacedAssembly, replacement.first, replacement.second);
-		assembly = &replacedAssembly;
-	}
-
 	int startStackHeight = stackHeight();
 
 	julia::ExternalIdentifierAccess identifierAccess;
@@ -320,7 +310,7 @@ void CompilerContext::appendInlineAssembly(
 
 	ErrorList errors;
 	ErrorReporter errorReporter(errors);
-	auto scanner = make_shared<Scanner>(CharStream(*assembly), "--CODEGEN--");
+	auto scanner = make_shared<Scanner>(CharStream(_assembly), "--CODEGEN--");
 	auto parserResult = assembly::Parser(errorReporter).parse(scanner);
 	solAssert(parserResult, "Failed to parse inline assembly block.");
 	solAssert(errorReporter.errors().empty(), "Failed to parse inline assembly block.");
@@ -329,7 +319,7 @@ void CompilerContext::appendInlineAssembly(
 	assembly::AsmAnalyzer analyzer(analysisInfo, errorReporter, false, identifierAccess.resolve);
 	solAssert(analyzer.analyze(*parserResult), "Failed to analyze inline assembly block.");
 	solAssert(errorReporter.errors().empty(), "Failed to analyze inline assembly block.");
-	assembly::CodeGenerator::assemble(*parserResult, analysisInfo, *m_asm, identifierAccess);
+	assembly::CodeGenerator::assemble(*parserResult, analysisInfo, *m_asm, identifierAccess, _system);
 }
 
 FunctionDefinition const& CompilerContext::resolveVirtualFunction(
diff --git a/libsolidity/codegen/CompilerContext.h b/libsolidity/codegen/CompilerContext.h
index 5116585e..dd36bba0 100644
--- a/libsolidity/codegen/CompilerContext.h
+++ b/libsolidity/codegen/CompilerContext.h
@@ -156,6 +156,8 @@ public:
 	eth::AssemblyItem pushNewTag() { return m_asm->append(m_asm->newPushTag()).tag(); }
 	/// @returns a new tag without pushing any opcodes or data
 	eth::AssemblyItem newTag() { return m_asm->newTag(); }
+	/// @returns a new tag identified by name.
+	eth::AssemblyItem namedTag(std::string const& _name) { return m_asm->namedTag(_name); }
 	/// Adds a subroutine to the code (in the data section) and pushes its size (via a tag)
 	/// on the stack. @returns the pushsub assembly item.
 	eth::AssemblyItem addSubroutine(eth::AssemblyPointer const& _assembly) { return m_asm->appendSubroutine(_assembly); }
@@ -185,10 +187,11 @@ public:
 	/// Appends inline assembly. @a _replacements are string-matching replacements that are performed
 	/// prior to parsing the inline assembly.
 	/// @param _localVariables assigns stack positions to variables with the last one being the stack top
+	/// @param _system if true, this is a "system-level" assembly where all functions use named labels.
 	void appendInlineAssembly(
 		std::string const& _assembly,
 		std::vector<std::string> const& _localVariables = std::vector<std::string>(),
-		std::map<std::string, std::string> const& _replacements = std::map<std::string, std::string>{}
+		bool _system = false
 	);
 
 	/// Appends arbitrary data to the end of the bytecode.
diff --git a/libsolidity/codegen/CompilerUtils.cpp b/libsolidity/codegen/CompilerUtils.cpp
index 146472f9..3662478d 100644
--- a/libsolidity/codegen/CompilerUtils.cpp
+++ b/libsolidity/codegen/CompilerUtils.cpp
@@ -319,7 +319,7 @@ void CompilerUtils::abiEncode(
 	ABIFunctions funs;
 	string routine = funs.tupleEncoder(_givenTypes, _targetTypes, _encodeAsLibraryTypes);
 	routine += funs.requestedFunctions();
-	m_context.appendInlineAssembly("{" + routine + "}", variables);
+	m_context.appendInlineAssembly("{" + routine + "}", variables, true);
 	// Remove everyhing except for "value0" / the final memory pointer.
 	popStackSlots(numValues);
 }
diff --git a/libsolidity/inlineasm/AsmCodeGen.cpp b/libsolidity/inlineasm/AsmCodeGen.cpp
index 6d0c0255..dded9f76 100644
--- a/libsolidity/inlineasm/AsmCodeGen.cpp
+++ b/libsolidity/inlineasm/AsmCodeGen.cpp
@@ -83,6 +83,10 @@ public:
 	{
 		return assemblyTagToIdentifier(m_assembly.newTag());
 	}
+	virtual size_t namedLabel(std::string const& _name) override
+	{
+		return assemblyTagToIdentifier(m_assembly.namedTag(_name));
+	}
 	virtual void appendLinkerSymbol(std::string const& _linkerSymbol) override
 	{
 		m_assembly.appendLibraryAddress(_linkerSymbol);
@@ -141,9 +145,17 @@ void assembly::CodeGenerator::assemble(
 	Block const& _parsedData,
 	AsmAnalysisInfo& _analysisInfo,
 	eth::Assembly& _assembly,
-	julia::ExternalIdentifierAccess const& _identifierAccess
+	julia::ExternalIdentifierAccess const& _identifierAccess,
+	bool _useNamedLabelsForFunctions
 )
 {
 	EthAssemblyAdapter assemblyAdapter(_assembly);
-	julia::CodeTransform(assemblyAdapter, _analysisInfo, false, false, _identifierAccess)(_parsedData);
+	julia::CodeTransform(
+		assemblyAdapter,
+		_analysisInfo,
+		false,
+		false,
+		_identifierAccess,
+		_useNamedLabelsForFunctions
+	)(_parsedData);
 }
diff --git a/libsolidity/inlineasm/AsmCodeGen.h b/libsolidity/inlineasm/AsmCodeGen.h
index 2a36a590..a7d7ead1 100644
--- a/libsolidity/inlineasm/AsmCodeGen.h
+++ b/libsolidity/inlineasm/AsmCodeGen.h
@@ -46,7 +46,8 @@ public:
 		Block const& _parsedData,
 		AsmAnalysisInfo& _analysisInfo,
 		eth::Assembly& _assembly,
-		julia::ExternalIdentifierAccess const& _identifierAccess = julia::ExternalIdentifierAccess()
+		julia::ExternalIdentifierAccess const& _identifierAccess = julia::ExternalIdentifierAccess(),
+		bool _useNamedLabelsForFunctions = false
 	);
 };
 
diff --git a/test/libsolidity/ABIEncoderTests.cpp b/test/libsolidity/ABIEncoderTests.cpp
index 297c4ef0..4ddf17ce 100644
--- a/test/libsolidity/ABIEncoderTests.cpp
+++ b/test/libsolidity/ABIEncoderTests.cpp
@@ -398,6 +398,34 @@ BOOST_AUTO_TEST_CASE(calldata)
 	)
 }
 
+BOOST_AUTO_TEST_CASE(function_name_collision)
+{
+	// This tests a collision between a function name used by inline assembly
+	// and by the ABI encoder
+	string sourceCode = R"(
+		contract C {
+			function f(uint x) returns (uint) {
+				assembly {
+					function abi_encode_t_uint256_to_t_uint256() {
+						mstore(0, 7)
+						return(0, 0x20)
+					}
+					switch x
+					case 0 { abi_encode_t_uint256_to_t_uint256() }
+				}
+				return 1;
+			}
+		}
+	)";
+	BOTH_ENCODERS(
+		compileAndRun(sourceCode);
+		BOOST_CHECK(callContractFunction("f(uint256)", encodeArgs(0)) == encodeArgs(7));
+		BOOST_CHECK(callContractFunction("f(uint256)", encodeArgs(1)) == encodeArgs(1));
+	)
+}
+
+
+
 BOOST_AUTO_TEST_SUITE_END()
 
 }