Merge pull request #1627 from ethereum/asmfunctions

Parsing assembly function definitions and calls.

7 files changed, 162 insertions, 41 deletions

diff --git a/libsolidity/inlineasm/AsmCodeGen.cpp b/libsolidity/inlineasm/AsmCodeGen.cpp
index 43c3b27a..faa7dabd 100644
--- a/libsolidity/inlineasm/AsmCodeGen.cpp
+++ b/libsolidity/inlineasm/AsmCodeGen.cpp
@@ -190,6 +190,10 @@ public:
 		}
 		(*this)(_instr.instruction);
 	}
+	void operator()(assembly::FunctionCall const&)
+	{
+		solAssert(false, "Function call not removed during desugaring phase.");
+	}
 	void operator()(Label const& _label)
 	{
 		m_state.assembly.setSourceLocation(_label.location);
@@ -249,7 +253,10 @@ public:
 				_block.location
 			);
 		}
-
+	}
+	void operator()(assembly::FunctionDefinition const&)
+	{
+		solAssert(false, "Function definition not removed during desugaring phase.");
 	}
 
 private:
diff --git a/libsolidity/inlineasm/AsmData.h b/libsolidity/inlineasm/AsmData.h
index d622ff54..d61b5803 100644
--- a/libsolidity/inlineasm/AsmData.h
+++ b/libsolidity/inlineasm/AsmData.h
@@ -48,17 +48,22 @@ struct Label { SourceLocation location; std::string name; };
 struct Assignment { SourceLocation location; Identifier variableName; };
 struct FunctionalAssignment;
 struct VariableDeclaration;
+struct FunctionDefinition;
+struct FunctionCall;
 struct Block;
-using Statement = boost::variant<Instruction, Literal, Label, Assignment, Identifier, FunctionalAssignment, FunctionalInstruction, VariableDeclaration, Block>;
+using Statement = boost::variant<Instruction, Literal, Label, Assignment, Identifier, FunctionalAssignment, FunctionCall, FunctionalInstruction, VariableDeclaration, FunctionDefinition, Block>;
 /// Functional assignment ("x := mload(20)", expects push-1-expression on the right hand
 /// side and requires x to occupy exactly one stack slot.
 struct FunctionalAssignment { SourceLocation location; Identifier variableName; std::shared_ptr<Statement> value; };
 /// Functional instruction, e.g. "mul(mload(20), add(2, x))"
 struct FunctionalInstruction { SourceLocation location; Instruction instruction; std::vector<Statement> arguments; };
+struct FunctionCall { SourceLocation location; Identifier functionName; std::vector<Statement> arguments; };
 /// Block-scope variable declaration ("let x := mload(20)"), non-hoisted
 struct VariableDeclaration { SourceLocation location; std::string name; std::shared_ptr<Statement> value; };
 /// Block that creates a scope (frees declared stack variables)
 struct Block { SourceLocation location; std::vector<Statement> statements; };
+/// Function definition ("function f(a, b) -> (d, e) { ... }")
+struct FunctionDefinition { SourceLocation location; std::string name; std::vector<std::string> arguments; std::vector<std::string> returns; Block body; };
 
 struct LocationExtractor: boost::static_visitor<SourceLocation>
 {
diff --git a/libsolidity/inlineasm/AsmParser.cpp b/libsolidity/inlineasm/AsmParser.cpp
index 46a2730d..0fc0a34f 100644
--- a/libsolidity/inlineasm/AsmParser.cpp
+++ b/libsolidity/inlineasm/AsmParser.cpp
@@ -62,6 +62,8 @@ assembly::Statement Parser::parseStatement()
 	{
 	case Token::Let:
 		return parseVariableDeclaration();
+	case Token::Function:
+		return parseFunctionDefinition();
 	case Token::LBrace:
 		return parseBlock();
 	case Token::Assign:
@@ -214,10 +216,7 @@ assembly::VariableDeclaration Parser::parseVariableDeclaration()
 {
 	VariableDeclaration varDecl = createWithLocation<VariableDeclaration>();
 	expectToken(Token::Let);
-	varDecl.name = m_scanner->currentLiteral();
-	if (instructions().count(varDecl.name))
-		fatalParserError("Cannot use instruction names for identifier names.");
-	expectToken(Token::Identifier);
+	varDecl.name = expectAsmIdentifier();
 	expectToken(Token::Colon);
 	expectToken(Token::Assign);
 	varDecl.value.reset(new Statement(parseExpression()));
@@ -225,44 +224,107 @@ assembly::VariableDeclaration Parser::parseVariableDeclaration()
 	return varDecl;
 }
 
-FunctionalInstruction Parser::parseFunctionalInstruction(assembly::Statement&& _instruction)
+assembly::FunctionDefinition Parser::parseFunctionDefinition()
 {
-	if (_instruction.type() != typeid(Instruction))
-		fatalParserError("Assembly instruction required in front of \"(\")");
-	FunctionalInstruction ret;
-	ret.instruction = std::move(boost::get<Instruction>(_instruction));
-	ret.location = ret.instruction.location;
-	solidity::Instruction instr = ret.instruction.instruction;
-	InstructionInfo instrInfo = instructionInfo(instr);
-	if (solidity::Instruction::DUP1 <= instr && instr <= solidity::Instruction::DUP16)
-		fatalParserError("DUPi instructions not allowed for functional notation");
-	if (solidity::Instruction::SWAP1 <= instr && instr <= solidity::Instruction::SWAP16)
-		fatalParserError("SWAPi instructions not allowed for functional notation");
-
+	FunctionDefinition funDef = createWithLocation<FunctionDefinition>();
+	expectToken(Token::Function);
+	funDef.name = expectAsmIdentifier();
 	expectToken(Token::LParen);
-	unsigned args = unsigned(instrInfo.args);
-	for (unsigned i = 0; i < args; ++i)
+	while (m_scanner->currentToken() != Token::RParen)
 	{
-		ret.arguments.emplace_back(parseExpression());
-		if (i != args - 1)
+		funDef.arguments.push_back(expectAsmIdentifier());
+		if (m_scanner->currentToken() == Token::RParen)
+			break;
+		expectToken(Token::Comma);
+	}
+	expectToken(Token::RParen);
+	if (m_scanner->currentToken() == Token::Sub)
+	{
+		expectToken(Token::Sub);
+		expectToken(Token::GreaterThan);
+		expectToken(Token::LParen);
+		while (true)
 		{
-			if (m_scanner->currentToken() != Token::Comma)
-				fatalParserError(string(
-					"Expected comma (" +
-					instrInfo.name +
-					" expects " +
-					boost::lexical_cast<string>(args) +
-					" arguments)"
-				));
-			else
-				m_scanner->next();
+			funDef.returns.push_back(expectAsmIdentifier());
+			if (m_scanner->currentToken() == Token::RParen)
+				break;
+			expectToken(Token::Comma);
 		}
+		expectToken(Token::RParen);
 	}
-	ret.location.end = endPosition();
-	if (m_scanner->currentToken() == Token::Comma)
-		fatalParserError(
-			string("Expected ')' (" + instrInfo.name + " expects " + boost::lexical_cast<string>(args) + " arguments)")
-		);
-	expectToken(Token::RParen);
-	return ret;
+	funDef.body = parseBlock();
+	funDef.location.end = funDef.body.location.end;
+	return funDef;
+}
+
+assembly::Statement Parser::parseFunctionalInstruction(assembly::Statement&& _instruction)
+{
+	if (_instruction.type() == typeid(Instruction))
+	{
+		FunctionalInstruction ret;
+		ret.instruction = std::move(boost::get<Instruction>(_instruction));
+		ret.location = ret.instruction.location;
+		solidity::Instruction instr = ret.instruction.instruction;
+		InstructionInfo instrInfo = instructionInfo(instr);
+		if (solidity::Instruction::DUP1 <= instr && instr <= solidity::Instruction::DUP16)
+			fatalParserError("DUPi instructions not allowed for functional notation");
+		if (solidity::Instruction::SWAP1 <= instr && instr <= solidity::Instruction::SWAP16)
+			fatalParserError("SWAPi instructions not allowed for functional notation");
+		expectToken(Token::LParen);
+		unsigned args = unsigned(instrInfo.args);
+		for (unsigned i = 0; i < args; ++i)
+		{
+			ret.arguments.emplace_back(parseExpression());
+			if (i != args - 1)
+			{
+				if (m_scanner->currentToken() != Token::Comma)
+					fatalParserError(string(
+						"Expected comma (" +
+						instrInfo.name +
+						" expects " +
+						boost::lexical_cast<string>(args) +
+						" arguments)"
+					));
+				else
+					m_scanner->next();
+			}
+		}
+		ret.location.end = endPosition();
+		if (m_scanner->currentToken() == Token::Comma)
+			fatalParserError(
+				string("Expected ')' (" + instrInfo.name + " expects " + boost::lexical_cast<string>(args) + " arguments)")
+			);
+		expectToken(Token::RParen);
+		return ret;
+	}
+	else if (_instruction.type() == typeid(Identifier))
+	{
+		FunctionCall ret;
+		ret.functionName = std::move(boost::get<Identifier>(_instruction));
+		ret.location = ret.functionName.location;
+		expectToken(Token::LParen);
+		while (m_scanner->currentToken() != Token::RParen)
+		{
+			ret.arguments.emplace_back(parseExpression());
+			if (m_scanner->currentToken() == Token::RParen)
+				break;
+			expectToken(Token::Comma);
+		}
+		ret.location.end = endPosition();
+		expectToken(Token::RParen);
+		return ret;
+	}
+	else
+		fatalParserError("Assembly instruction or function name required in front of \"(\")");
+
+	return {};
+}
+
+string Parser::expectAsmIdentifier()
+{
+	string name = m_scanner->currentLiteral();
+	if (instructions().count(name))
+		fatalParserError("Cannot use instruction names for identifier names.");
+	expectToken(Token::Identifier);
+	return name;
 }
diff --git a/libsolidity/inlineasm/AsmParser.h b/libsolidity/inlineasm/AsmParser.h
index 643548dd..4b4a24ae 100644
--- a/libsolidity/inlineasm/AsmParser.h
+++ b/libsolidity/inlineasm/AsmParser.h
@@ -67,7 +67,9 @@ protected:
 	std::map<std::string, dev::solidity::Instruction> const& instructions();
 	Statement parseElementaryOperation(bool _onlySinglePusher = false);
 	VariableDeclaration parseVariableDeclaration();
-	FunctionalInstruction parseFunctionalInstruction(Statement&& _instruction);
+	FunctionDefinition parseFunctionDefinition();
+	Statement parseFunctionalInstruction(Statement&& _instruction);
+	std::string expectAsmIdentifier();
 };
 
 }
diff --git a/libsolidity/inlineasm/AsmPrinter.cpp b/libsolidity/inlineasm/AsmPrinter.cpp
index ab2a03ff..a70b0b78 100644
--- a/libsolidity/inlineasm/AsmPrinter.cpp
+++ b/libsolidity/inlineasm/AsmPrinter.cpp
@@ -112,6 +112,24 @@ string AsmPrinter::operator()(assembly::VariableDeclaration const& _variableDecl
 	return "let " + _variableDeclaration.name + " := " + boost::apply_visitor(*this, *_variableDeclaration.value);
 }
 
+string AsmPrinter::operator()(assembly::FunctionDefinition const& _functionDefinition)
+{
+	string out = "function " + _functionDefinition.name + "(" + boost::algorithm::join(_functionDefinition.arguments, ", ") + ")";
+	if (!_functionDefinition.returns.empty())
+		out += " -> (" + boost::algorithm::join(_functionDefinition.returns, ", ") + ")";
+	return out + "\n" + (*this)(_functionDefinition.body);
+}
+
+string AsmPrinter::operator()(assembly::FunctionCall const& _functionCall)
+{
+	return
+		(*this)(_functionCall.functionName) + "(" +
+		boost::algorithm::join(
+			_functionCall.arguments | boost::adaptors::transformed(boost::apply_visitor(*this)),
+			", " ) +
+		")";
+}
+
 string AsmPrinter::operator()(Block const& _block)
 {
 	if (_block.statements.empty())
diff --git a/libsolidity/inlineasm/AsmPrinter.h b/libsolidity/inlineasm/AsmPrinter.h
index 39069d02..a7a1de0a 100644
--- a/libsolidity/inlineasm/AsmPrinter.h
+++ b/libsolidity/inlineasm/AsmPrinter.h
@@ -53,6 +53,8 @@ public:
 	std::string operator()(assembly::Assignment const& _assignment);
 	std::string operator()(assembly::FunctionalAssignment const& _functionalAssignment);
 	std::string operator()(assembly::VariableDeclaration const& _variableDeclaration);
+	std::string operator()(assembly::FunctionDefinition const& _functionDefinition);
+	std::string operator()(assembly::FunctionCall const& _functionCall);
 	std::string operator()(assembly::Block const& _block);
 };
 
diff --git a/test/libsolidity/InlineAssembly.cpp b/test/libsolidity/InlineAssembly.cpp
index 8744d96f..ddbc3c63 100644
--- a/test/libsolidity/InlineAssembly.cpp
+++ b/test/libsolidity/InlineAssembly.cpp
@@ -159,6 +159,21 @@ BOOST_AUTO_TEST_CASE(blocks)
 	BOOST_CHECK(successParse("{ let x := 7 { let y := 3 } { let z := 2 } }"));
 }
 
+BOOST_AUTO_TEST_CASE(function_definitions)
+{
+	BOOST_CHECK(successParse("{ function f() { } function g(a) -> (x) { } }"));
+}
+
+BOOST_AUTO_TEST_CASE(function_definitions_multiple_args)
+{
+	BOOST_CHECK(successParse("{ function f(a, d) { } function g(a, d) -> (x, y) { } }"));
+}
+
+BOOST_AUTO_TEST_CASE(function_calls)
+{
+	BOOST_CHECK(successParse("{ g(1, 2, f(mul(2, 3))) x() }"));
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 BOOST_AUTO_TEST_SUITE(Printing)
@@ -209,6 +224,16 @@ BOOST_AUTO_TEST_CASE(print_string_literal_unicode)
 	parsePrintCompare(parsed);
 }
 
+BOOST_AUTO_TEST_CASE(function_definitions_multiple_args)
+{
+	parsePrintCompare("{\n    function f(a, d)\n    {\n        mstore(a, d)\n    }\n    function g(a, d) -> (x, y)\n    {\n    }\n}");
+}
+
+BOOST_AUTO_TEST_CASE(function_calls)
+{
+	parsePrintCompare("{\n    g(1, mul(2, x), f(mul(2, 3)))\n    x()\n}");
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 BOOST_AUTO_TEST_SUITE(Analysis)