Implement switch statement in the assembly parser/printer

10 files changed, 95 insertions, 2 deletions

diff --git a/libsolidity/inlineasm/AsmAnalysis.cpp b/libsolidity/inlineasm/AsmAnalysis.cpp
index 65b935f2..ecc63372 100644
--- a/libsolidity/inlineasm/AsmAnalysis.cpp
+++ b/libsolidity/inlineasm/AsmAnalysis.cpp
@@ -285,6 +285,38 @@ bool AsmAnalyzer::operator()(assembly::FunctionCall const& _funCall)
 	return success;
 }
 
+bool AsmAnalyzer::operator()(Switch const& _switch)
+{
+	int const initialStackHeight = m_stackHeight;
+	if (!boost::apply_visitor(*this, *_switch.expression))
+		return false;
+	expectDeposit(1, initialStackHeight, locationOf(*_switch.expression));
+
+	map<string, bool> caseNames;
+	for (auto const& _case: _switch.cases)
+	{
+		/// Note: the parser ensures there is only one default case
+		if (caseNames[_case.name])
+		{
+			m_errors.push_back(make_shared<Error>(
+				Error::Type::DeclarationError,
+				"Duplicate case defined: " + _case.name,
+				_case.location
+			));
+			return false;
+		}
+		else
+			caseNames[_case.name] = true;
+
+		if (!(*this)(_case.body))
+			return false;
+	}
+
+	m_stackHeight--;
+
+	return true;
+}
+
 bool AsmAnalyzer::operator()(Block const& _block)
 {
 	bool success = true;
diff --git a/libsolidity/inlineasm/AsmAnalysis.h b/libsolidity/inlineasm/AsmAnalysis.h
index f09e4b59..9f022b12 100644
--- a/libsolidity/inlineasm/AsmAnalysis.h
+++ b/libsolidity/inlineasm/AsmAnalysis.h
@@ -47,6 +47,7 @@ struct Identifier;
 struct StackAssignment;
 struct FunctionDefinition;
 struct FunctionCall;
+struct Switch;
 
 struct Scope;
 
@@ -78,6 +79,7 @@ public:
 	bool operator()(assembly::VariableDeclaration const& _variableDeclaration);
 	bool operator()(assembly::FunctionDefinition const& _functionDefinition);
 	bool operator()(assembly::FunctionCall const& _functionCall);
+	bool operator()(assembly::Switch const& _switch);
 	bool operator()(assembly::Block const& _block);
 
 private:
diff --git a/libsolidity/inlineasm/AsmAnalysisInfo.h b/libsolidity/inlineasm/AsmAnalysisInfo.h
index d2253c78..18382db0 100644
--- a/libsolidity/inlineasm/AsmAnalysisInfo.h
+++ b/libsolidity/inlineasm/AsmAnalysisInfo.h
@@ -43,10 +43,11 @@ struct Identifier;
 struct StackAssignment;
 struct FunctionDefinition;
 struct FunctionCall;
+struct Switch;
 
 struct Scope;
 
-using Statement = boost::variant<Instruction, Literal, Label, StackAssignment, Identifier, Assignment, FunctionCall, FunctionalInstruction, VariableDeclaration, FunctionDefinition, Block>;
+using Statement = boost::variant<Instruction, Literal, Label, StackAssignment, Identifier, Assignment, FunctionCall, FunctionalInstruction, VariableDeclaration, FunctionDefinition, Switch, Block>;
 
 struct AsmAnalysisInfo
 {
diff --git a/libsolidity/inlineasm/AsmCodeGen.cpp b/libsolidity/inlineasm/AsmCodeGen.cpp
index 53eafc96..5c66b125 100644
--- a/libsolidity/inlineasm/AsmCodeGen.cpp
+++ b/libsolidity/inlineasm/AsmCodeGen.cpp
@@ -266,6 +266,10 @@ public:
 		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.");
diff --git a/libsolidity/inlineasm/AsmData.h b/libsolidity/inlineasm/AsmData.h
index 3b4048c3..92ff1c5a 100644
--- a/libsolidity/inlineasm/AsmData.h
+++ b/libsolidity/inlineasm/AsmData.h
@@ -50,9 +50,10 @@ struct VariableDeclaration;
 struct FunctionalInstruction;
 struct FunctionDefinition;
 struct FunctionCall;
+struct Switch;
 struct Block;
 
-using Statement = boost::variant<Instruction, Literal, Label, StackAssignment, Identifier, Assignment, FunctionCall, FunctionalInstruction, VariableDeclaration, FunctionDefinition, Block>;
+using Statement = boost::variant<Instruction, Literal, Label, StackAssignment, Identifier, Assignment, FunctionCall, FunctionalInstruction, VariableDeclaration, FunctionDefinition, Switch, Block>;
 
 /// Direct EVM instruction (except PUSHi and JUMPDEST)
 struct Instruction { SourceLocation location; solidity::Instruction instruction; };
@@ -77,6 +78,10 @@ struct VariableDeclaration { SourceLocation location; TypedNameList variables; s
 struct Block { SourceLocation location; std::vector<Statement> statements; };
 /// Function definition ("function f(a, b) -> (d, e) { ... }")
 struct FunctionDefinition { SourceLocation location; std::string name; TypedNameList arguments; TypedNameList returns; Block body; };
+/// Switch case or default case
+struct Case { SourceLocation location; std::string name; Block body; };
+/// Switch statement
+struct Switch { SourceLocation location; std::shared_ptr<Statement> expression; std::vector<Case> cases; };
 
 struct LocationExtractor: boost::static_visitor<SourceLocation>
 {
diff --git a/libsolidity/inlineasm/AsmParser.cpp b/libsolidity/inlineasm/AsmParser.cpp
index 530cd726..a3a25a42 100644
--- a/libsolidity/inlineasm/AsmParser.cpp
+++ b/libsolidity/inlineasm/AsmParser.cpp
@@ -67,6 +67,20 @@ assembly::Statement Parser::parseStatement()
 		return parseFunctionDefinition();
 	case Token::LBrace:
 		return parseBlock();
+	case Token::Switch:
+	{
+		assembly::Switch _switch = createWithLocation<assembly::Switch>();
+		m_scanner->next();
+		_switch.expression = make_shared<Statement>(parseExpression());
+		while (m_scanner->currentToken() == Token::Case)
+			_switch.cases.emplace_back(parseCase());
+		if (m_scanner->currentToken() == Token::Default)
+			_switch.cases.emplace_back(parseCase(true));
+		if (_switch.cases.size() == 0)
+			fatalParserError("Switch statement without any cases.");
+		_switch.location.end = _switch.cases.back().body.location.end;
+		return _switch;
+	}
 	case Token::Assign:
 	{
 		if (m_julia)
@@ -134,6 +148,22 @@ assembly::Statement Parser::parseStatement()
 	return statement;
 }
 
+assembly::Case Parser::parseCase(bool _defaultCase)
+{
+	assembly::Case _case = createWithLocation<assembly::Case>();
+	if (_defaultCase)
+		expectToken(Token::Default);
+	else
+	{
+		expectToken(Token::Case);
+		_case.name = expectAsmIdentifier();
+	}
+	expectToken(Token::Colon);
+	_case.body = parseBlock();
+	_case.location.end = _case.body.location.end;
+	return _case;
+}
+
 assembly::Statement Parser::parseExpression()
 {
 	Statement operation = parseElementaryOperation(true);
diff --git a/libsolidity/inlineasm/AsmParser.h b/libsolidity/inlineasm/AsmParser.h
index 812762a6..d1d0c1cc 100644
--- a/libsolidity/inlineasm/AsmParser.h
+++ b/libsolidity/inlineasm/AsmParser.h
@@ -62,6 +62,7 @@ protected:
 
 	Block parseBlock();
 	Statement parseStatement();
+	Case parseCase(bool _defaultCase = false);
 	/// Parses a functional expression that has to push exactly one stack element
 	Statement parseExpression();
 	std::map<std::string, dev::solidity::Instruction> const& instructions();
diff --git a/libsolidity/inlineasm/AsmPrinter.cpp b/libsolidity/inlineasm/AsmPrinter.cpp
index 92b12423..92200f84 100644
--- a/libsolidity/inlineasm/AsmPrinter.cpp
+++ b/libsolidity/inlineasm/AsmPrinter.cpp
@@ -167,6 +167,20 @@ string AsmPrinter::operator()(assembly::FunctionCall const& _functionCall)
 		")";
 }
 
+string AsmPrinter::operator()(Switch const& _switch)
+{
+	string out = "switch " + boost::apply_visitor(*this, *_switch.expression);
+	for (auto const& _case: _switch.cases)
+	{
+		if (_case.name.empty())
+			out += "\ndefault: ";
+		else
+			out += "\ncase " + _case.name + ": ";
+		out += (*this)(_case.body);
+	}
+	return out;
+}
+
 string AsmPrinter::operator()(Block const& _block)
 {
 	if (_block.statements.empty())
diff --git a/libsolidity/inlineasm/AsmPrinter.h b/libsolidity/inlineasm/AsmPrinter.h
index 423eeefa..b0d7fc09 100644
--- a/libsolidity/inlineasm/AsmPrinter.h
+++ b/libsolidity/inlineasm/AsmPrinter.h
@@ -40,6 +40,7 @@ struct Assignment;
 struct VariableDeclaration;
 struct FunctionDefinition;
 struct FunctionCall;
+struct Switch;
 struct Block;
 
 class AsmPrinter: public boost::static_visitor<std::string>
@@ -57,6 +58,7 @@ public:
 	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::Switch const& _switch);
 	std::string operator()(assembly::Block const& _block);
 
 private:
diff --git a/libsolidity/inlineasm/AsmScopeFiller.h b/libsolidity/inlineasm/AsmScopeFiller.h
index b1b0833b..0f5a5dd6 100644
--- a/libsolidity/inlineasm/AsmScopeFiller.h
+++ b/libsolidity/inlineasm/AsmScopeFiller.h
@@ -46,6 +46,7 @@ struct Identifier;
 struct StackAssignment;
 struct FunctionDefinition;
 struct FunctionCall;
+struct Switch;
 
 struct Scope;
 
@@ -69,6 +70,7 @@ public:
 	bool operator()(assembly::VariableDeclaration const& _variableDeclaration);
 	bool operator()(assembly::FunctionDefinition const& _functionDefinition);
 	bool operator()(assembly::FunctionCall const&) { return true; }
+	bool operator()(assembly::Switch const&) { return true; };
 	bool operator()(assembly::Block const& _block);
 
 private: