Implement switch statement in the assembly parser/printer

This commit is contained in:
Alex Beregszaszi 2017-04-28 14:27:56 +01:00
parent af2d2499c1
commit b5080860d5
10 changed files with 95 additions and 2 deletions

View File

@ -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;

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@ -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:

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@ -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
{

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@ -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.");

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@ -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>
{

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@ -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);

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@ -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();

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@ -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())

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@ -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:

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@ -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: