solidity/libsolidity/codegen/ir/IRGeneratorForStatements.cpp
2020-04-16 00:33:45 +02:00

1874 lines
60 KiB
C++

/*
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/>.
*/
/**
* Component that translates Solidity code into Yul at statement level and below.
*/
#include <libsolidity/codegen/ir/IRGeneratorForStatements.h>
#include <libsolidity/codegen/ABIFunctions.h>
#include <libsolidity/codegen/ir/IRGenerationContext.h>
#include <libsolidity/codegen/ir/IRLValue.h>
#include <libsolidity/codegen/ir/IRVariable.h>
#include <libsolidity/codegen/YulUtilFunctions.h>
#include <libsolidity/codegen/ABIFunctions.h>
#include <libsolidity/codegen/CompilerUtils.h>
#include <libsolidity/codegen/ReturnInfo.h>
#include <libsolidity/ast/TypeProvider.h>
#include <libevmasm/GasMeter.h>
#include <libyul/AsmPrinter.h>
#include <libyul/AsmData.h>
#include <libyul/Dialect.h>
#include <libyul/optimiser/ASTCopier.h>
#include <libsolutil/Whiskers.h>
#include <libsolutil/StringUtils.h>
#include <libsolutil/Keccak256.h>
#include <libsolutil/Visitor.h>
#include <boost/range/adaptor/reversed.hpp>
#include <boost/range/adaptor/transformed.hpp>
using namespace std;
using namespace solidity;
using namespace solidity::util;
using namespace solidity::frontend;
using namespace std::string_literals;
namespace
{
struct CopyTranslate: public yul::ASTCopier
{
using ExternalRefsMap = std::map<yul::Identifier const*, InlineAssemblyAnnotation::ExternalIdentifierInfo>;
CopyTranslate(yul::Dialect const& _dialect, IRGenerationContext& _context, ExternalRefsMap const& _references):
m_dialect(_dialect), m_context(_context), m_references(_references) {}
using ASTCopier::operator();
yul::Expression operator()(yul::Identifier const& _identifier) override
{
if (m_references.count(&_identifier))
{
auto const& reference = m_references.at(&_identifier);
auto const varDecl = dynamic_cast<VariableDeclaration const*>(reference.declaration);
solUnimplementedAssert(varDecl, "");
if (reference.isOffset || reference.isSlot)
{
solAssert(reference.isOffset != reference.isSlot, "");
pair<u256, unsigned> slot_offset = m_context.storageLocationOfVariable(*varDecl);
string const value = reference.isSlot ?
slot_offset.first.str() :
to_string(slot_offset.second);
return yul::Literal{
_identifier.location,
yul::LiteralKind::Number,
yul::YulString{value},
{}
};
}
}
return ASTCopier::operator()(_identifier);
}
yul::YulString translateIdentifier(yul::YulString _name) override
{
// Strictly, the dialect used by inline assembly (m_dialect) could be different
// from the Yul dialect we are compiling to. So we are assuming here that the builtin
// functions are identical. This should not be a problem for now since everything
// is EVM anyway.
if (m_dialect.builtin(_name))
return _name;
else
return yul::YulString{"usr$" + _name.str()};
}
yul::Identifier translate(yul::Identifier const& _identifier) override
{
if (!m_references.count(&_identifier))
return ASTCopier::translate(_identifier);
auto const& reference = m_references.at(&_identifier);
auto const varDecl = dynamic_cast<VariableDeclaration const*>(reference.declaration);
solUnimplementedAssert(varDecl, "");
solAssert(
reference.isOffset == false && reference.isSlot == false,
"Should not be called for offset/slot"
);
return yul::Identifier{
_identifier.location,
yul::YulString{m_context.localVariable(*varDecl).name()}
};
}
private:
yul::Dialect const& m_dialect;
IRGenerationContext& m_context;
ExternalRefsMap const& m_references;
};
}
string IRGeneratorForStatements::code() const
{
solAssert(!m_currentLValue, "LValue not reset!");
return m_code.str();
}
void IRGeneratorForStatements::initializeStateVar(VariableDeclaration const& _varDecl)
{
solAssert(m_context.isStateVariable(_varDecl), "Must be a state variable.");
solAssert(!_varDecl.isConstant(), "");
solAssert(!_varDecl.immutable(), "");
if (_varDecl.value())
{
_varDecl.value()->accept(*this);
writeToLValue(IRLValue{
*_varDecl.annotation().type,
IRLValue::Storage{
util::toCompactHexWithPrefix(m_context.storageLocationOfVariable(_varDecl).first),
m_context.storageLocationOfVariable(_varDecl).second
}
}, *_varDecl.value());
}
}
void IRGeneratorForStatements::initializeLocalVar(VariableDeclaration const& _varDecl)
{
solAssert(m_context.isLocalVariable(_varDecl), "Must be a local variable.");
auto const* type = _varDecl.type();
if (auto const* refType = dynamic_cast<ReferenceType const*>(type))
if (refType->dataStoredIn(DataLocation::Storage) && refType->isPointer())
return;
IRVariable zero = zeroValue(*type);
assign(m_context.localVariable(_varDecl), zero);
}
void IRGeneratorForStatements::endVisit(VariableDeclarationStatement const& _varDeclStatement)
{
if (Expression const* expression = _varDeclStatement.initialValue())
{
if (_varDeclStatement.declarations().size() > 1)
{
auto const* tupleType = dynamic_cast<TupleType const*>(expression->annotation().type);
solAssert(tupleType, "Expected expression of tuple type.");
solAssert(_varDeclStatement.declarations().size() == tupleType->components().size(), "Invalid number of tuple components.");
for (size_t i = 0; i < _varDeclStatement.declarations().size(); ++i)
if (auto const& decl = _varDeclStatement.declarations()[i])
{
solAssert(tupleType->components()[i], "");
define(m_context.addLocalVariable(*decl), IRVariable(*expression).tupleComponent(i));
}
}
else
{
VariableDeclaration const& varDecl = *_varDeclStatement.declarations().front();
define(m_context.addLocalVariable(varDecl), *expression);
}
}
else
for (auto const& decl: _varDeclStatement.declarations())
if (decl)
{
declare(m_context.addLocalVariable(*decl));
initializeLocalVar(*decl);
}
}
bool IRGeneratorForStatements::visit(Conditional const& _conditional)
{
_conditional.condition().accept(*this);
string condition = expressionAsType(_conditional.condition(), *TypeProvider::boolean());
declare(_conditional);
m_code << "switch " << condition << "\n" "case 0 {\n";
_conditional.falseExpression().accept(*this);
assign(_conditional, _conditional.falseExpression());
m_code << "}\n" "default {\n";
_conditional.trueExpression().accept(*this);
assign(_conditional, _conditional.trueExpression());
m_code << "}\n";
return false;
}
bool IRGeneratorForStatements::visit(Assignment const& _assignment)
{
_assignment.rightHandSide().accept(*this);
Type const* intermediateType = type(_assignment.rightHandSide()).closestTemporaryType(
&type(_assignment.leftHandSide())
);
IRVariable value = convert(_assignment.rightHandSide(), *intermediateType);
_assignment.leftHandSide().accept(*this);
solAssert(!!m_currentLValue, "LValue not retrieved.");
if (_assignment.assignmentOperator() != Token::Assign)
{
solAssert(type(_assignment.leftHandSide()) == *intermediateType, "");
solAssert(intermediateType->isValueType(), "Compound operators only available for value types.");
IRVariable leftIntermediate = readFromLValue(*m_currentLValue);
m_code << value.name() << " := " << binaryOperation(
TokenTraits::AssignmentToBinaryOp(_assignment.assignmentOperator()),
*intermediateType,
leftIntermediate.name(),
value.name()
);
}
writeToLValue(*m_currentLValue, value);
m_currentLValue.reset();
if (*_assignment.annotation().type != *TypeProvider::emptyTuple())
define(_assignment, value);
return false;
}
bool IRGeneratorForStatements::visit(TupleExpression const& _tuple)
{
if (_tuple.isInlineArray())
solUnimplementedAssert(false, "");
else
{
bool lValueRequested = _tuple.annotation().lValueRequested;
if (lValueRequested)
solAssert(!m_currentLValue, "");
if (_tuple.components().size() == 1)
{
solAssert(_tuple.components().front(), "");
_tuple.components().front()->accept(*this);
if (lValueRequested)
solAssert(!!m_currentLValue, "");
else
define(_tuple, *_tuple.components().front());
}
else
{
vector<optional<IRLValue>> lvalues;
for (size_t i = 0; i < _tuple.components().size(); ++i)
if (auto const& component = _tuple.components()[i])
{
component->accept(*this);
if (lValueRequested)
{
solAssert(!!m_currentLValue, "");
lvalues.emplace_back(std::move(m_currentLValue));
m_currentLValue.reset();
}
else
define(IRVariable(_tuple).tupleComponent(i), *component);
}
else if (lValueRequested)
lvalues.emplace_back();
if (_tuple.annotation().lValueRequested)
m_currentLValue.emplace(IRLValue{
*_tuple.annotation().type,
IRLValue::Tuple{std::move(lvalues)}
});
}
}
return false;
}
bool IRGeneratorForStatements::visit(IfStatement const& _ifStatement)
{
_ifStatement.condition().accept(*this);
string condition = expressionAsType(_ifStatement.condition(), *TypeProvider::boolean());
if (_ifStatement.falseStatement())
{
m_code << "switch " << condition << "\n" "case 0 {\n";
_ifStatement.falseStatement()->accept(*this);
m_code << "}\n" "default {\n";
}
else
m_code << "if " << condition << " {\n";
_ifStatement.trueStatement().accept(*this);
m_code << "}\n";
return false;
}
bool IRGeneratorForStatements::visit(ForStatement const& _forStatement)
{
generateLoop(
_forStatement.body(),
_forStatement.condition(),
_forStatement.initializationExpression(),
_forStatement.loopExpression()
);
return false;
}
bool IRGeneratorForStatements::visit(WhileStatement const& _whileStatement)
{
generateLoop(
_whileStatement.body(),
&_whileStatement.condition(),
nullptr,
nullptr,
_whileStatement.isDoWhile()
);
return false;
}
bool IRGeneratorForStatements::visit(Continue const&)
{
m_code << "continue\n";
return false;
}
bool IRGeneratorForStatements::visit(Break const&)
{
m_code << "break\n";
return false;
}
void IRGeneratorForStatements::endVisit(Return const& _return)
{
if (Expression const* value = _return.expression())
{
solAssert(_return.annotation().functionReturnParameters, "Invalid return parameters pointer.");
vector<ASTPointer<VariableDeclaration>> const& returnParameters =
_return.annotation().functionReturnParameters->parameters();
if (returnParameters.size() > 1)
for (size_t i = 0; i < returnParameters.size(); ++i)
assign(m_context.localVariable(*returnParameters[i]), IRVariable(*value).tupleComponent(i));
else if (returnParameters.size() == 1)
assign(m_context.localVariable(*returnParameters.front()), *value);
}
m_code << "leave\n";
}
void IRGeneratorForStatements::endVisit(UnaryOperation const& _unaryOperation)
{
Type const& resultType = type(_unaryOperation);
Token const op = _unaryOperation.getOperator();
if (op == Token::Delete)
{
solAssert(!!m_currentLValue, "LValue not retrieved.");
std::visit(
util::GenericVisitor{
[&](IRLValue::Storage const& _storage) {
m_code <<
m_utils.storageSetToZeroFunction(m_currentLValue->type) <<
"(" <<
_storage.slot <<
", " <<
_storage.offsetString() <<
")\n";
m_currentLValue.reset();
},
[&](auto const&) {
IRVariable zeroValue(m_context.newYulVariable(), m_currentLValue->type);
define(zeroValue) << m_utils.zeroValueFunction(m_currentLValue->type) << "()\n";
writeToLValue(*m_currentLValue, zeroValue);
m_currentLValue.reset();
}
},
m_currentLValue->kind
);
}
else if (resultType.category() == Type::Category::RationalNumber)
define(_unaryOperation) << formatNumber(resultType.literalValue(nullptr)) << "\n";
else if (resultType.category() == Type::Category::Integer)
{
solAssert(resultType == type(_unaryOperation.subExpression()), "Result type doesn't match!");
if (op == Token::Inc || op == Token::Dec)
{
solAssert(!!m_currentLValue, "LValue not retrieved.");
IRVariable modifiedValue(m_context.newYulVariable(), resultType);
IRVariable originalValue = readFromLValue(*m_currentLValue);
define(modifiedValue) <<
(op == Token::Inc ?
m_utils.incrementCheckedFunction(resultType) :
m_utils.decrementCheckedFunction(resultType)
) <<
"(" <<
originalValue.name() <<
")\n";
writeToLValue(*m_currentLValue, modifiedValue);
m_currentLValue.reset();
define(_unaryOperation, _unaryOperation.isPrefixOperation() ? modifiedValue : originalValue);
}
else if (op == Token::BitNot)
appendSimpleUnaryOperation(_unaryOperation, _unaryOperation.subExpression());
else if (op == Token::Add)
// According to SyntaxChecker...
solAssert(false, "Use of unary + is disallowed.");
else if (op == Token::Sub)
{
IntegerType const& intType = *dynamic_cast<IntegerType const*>(&resultType);
define(_unaryOperation) <<
m_utils.negateNumberCheckedFunction(intType) <<
"(" <<
IRVariable(_unaryOperation.subExpression()).name() <<
")\n";
}
else
solUnimplementedAssert(false, "Unary operator not yet implemented");
}
else if (resultType.category() == Type::Category::Bool)
{
solAssert(
_unaryOperation.getOperator() != Token::BitNot,
"Bitwise Negation can't be done on bool!"
);
appendSimpleUnaryOperation(_unaryOperation, _unaryOperation.subExpression());
}
else
solUnimplementedAssert(false, "Unary operator not yet implemented");
}
bool IRGeneratorForStatements::visit(BinaryOperation const& _binOp)
{
solAssert(!!_binOp.annotation().commonType, "");
TypePointer commonType = _binOp.annotation().commonType;
langutil::Token op = _binOp.getOperator();
if (op == Token::And || op == Token::Or)
{
// This can short-circuit!
appendAndOrOperatorCode(_binOp);
return false;
}
_binOp.leftExpression().accept(*this);
_binOp.rightExpression().accept(*this);
if (commonType->category() == Type::Category::RationalNumber)
define(_binOp) << toCompactHexWithPrefix(commonType->literalValue(nullptr)) << "\n";
else if (TokenTraits::isCompareOp(op))
{
if (auto type = dynamic_cast<FunctionType const*>(commonType))
{
solAssert(op == Token::Equal || op == Token::NotEqual, "Invalid function pointer comparison!");
solAssert(type->kind() != FunctionType::Kind::External, "External function comparison not allowed!");
}
solAssert(commonType->isValueType(), "");
bool isSigned = false;
if (auto type = dynamic_cast<IntegerType const*>(commonType))
isSigned = type->isSigned();
string args =
expressionAsType(_binOp.leftExpression(), *commonType) +
", " +
expressionAsType(_binOp.rightExpression(), *commonType);
string expr;
if (op == Token::Equal)
expr = "eq(" + move(args) + ")";
else if (op == Token::NotEqual)
expr = "iszero(eq(" + move(args) + "))";
else if (op == Token::GreaterThanOrEqual)
expr = "iszero(" + string(isSigned ? "slt(" : "lt(") + move(args) + "))";
else if (op == Token::LessThanOrEqual)
expr = "iszero(" + string(isSigned ? "sgt(" : "gt(") + move(args) + "))";
else if (op == Token::GreaterThan)
expr = (isSigned ? "sgt(" : "gt(") + move(args) + ")";
else if (op == Token::LessThan)
expr = (isSigned ? "slt(" : "lt(") + move(args) + ")";
else
solAssert(false, "Unknown comparison operator.");
define(_binOp) << expr << "\n";
}
else
{
string left = expressionAsType(_binOp.leftExpression(), *commonType);
string right = expressionAsType(_binOp.rightExpression(), *commonType);
define(_binOp) << binaryOperation(_binOp.getOperator(), *commonType, left, right) << "\n";
}
return false;
}
void IRGeneratorForStatements::endVisit(FunctionCall const& _functionCall)
{
solUnimplementedAssert(
_functionCall.annotation().kind == FunctionCallKind::FunctionCall ||
_functionCall.annotation().kind == FunctionCallKind::TypeConversion,
"This type of function call is not yet implemented"
);
Type const& funcType = type(_functionCall.expression());
if (_functionCall.annotation().kind == FunctionCallKind::TypeConversion)
{
solAssert(funcType.category() == Type::Category::TypeType, "Expected category to be TypeType");
solAssert(_functionCall.arguments().size() == 1, "Expected one argument for type conversion");
define(_functionCall, *_functionCall.arguments().front());
return;
}
FunctionTypePointer functionType = dynamic_cast<FunctionType const*>(&funcType);
TypePointers parameterTypes = functionType->parameterTypes();
vector<ASTPointer<Expression const>> const& callArguments = _functionCall.arguments();
vector<ASTPointer<ASTString>> const& callArgumentNames = _functionCall.names();
if (!functionType->takesArbitraryParameters())
solAssert(callArguments.size() == parameterTypes.size(), "");
vector<ASTPointer<Expression const>> arguments;
if (callArgumentNames.empty())
// normal arguments
arguments = callArguments;
else
// named arguments
for (auto const& parameterName: functionType->parameterNames())
{
auto const it = std::find_if(callArgumentNames.cbegin(), callArgumentNames.cend(), [&](ASTPointer<ASTString> const& _argName) {
return *_argName == parameterName;
});
solAssert(it != callArgumentNames.cend(), "");
arguments.push_back(callArguments[std::distance(callArgumentNames.begin(), it)]);
}
solUnimplementedAssert(!functionType->bound(), "");
switch (functionType->kind())
{
case FunctionType::Kind::Internal:
{
vector<string> args;
for (unsigned i = 0; i < arguments.size(); ++i)
if (functionType->takesArbitraryParameters())
args.emplace_back(IRVariable(*arguments[i]).commaSeparatedList());
else
args.emplace_back(convert(*arguments[i], *parameterTypes[i]).commaSeparatedList());
if (auto identifier = dynamic_cast<Identifier const*>(&_functionCall.expression()))
{
solAssert(!functionType->bound(), "");
if (auto functionDef = dynamic_cast<FunctionDefinition const*>(identifier->annotation().referencedDeclaration))
{
define(_functionCall) <<
m_context.virtualFunctionName(*functionDef) <<
"(" <<
joinHumanReadable(args) <<
")\n";
return;
}
}
define(_functionCall) <<
m_context.internalDispatch(
TupleType(functionType->parameterTypes()).sizeOnStack(),
TupleType(functionType->returnParameterTypes()).sizeOnStack()
) <<
"(" <<
IRVariable(_functionCall.expression()).part("functionIdentifier").name() <<
joinHumanReadablePrefixed(args) <<
")\n";
break;
}
case FunctionType::Kind::External:
case FunctionType::Kind::DelegateCall:
case FunctionType::Kind::BareCall:
case FunctionType::Kind::BareDelegateCall:
case FunctionType::Kind::BareStaticCall:
appendExternalFunctionCall(_functionCall, arguments);
break;
case FunctionType::Kind::BareCallCode:
solAssert(false, "Callcode has been removed.");
case FunctionType::Kind::Event:
{
auto const& event = dynamic_cast<EventDefinition const&>(functionType->declaration());
TypePointers paramTypes = functionType->parameterTypes();
ABIFunctions abi(m_context.evmVersion(), m_context.revertStrings(), m_context.functionCollector());
vector<IRVariable> indexedArgs;
string nonIndexedArgs;
TypePointers nonIndexedArgTypes;
TypePointers nonIndexedParamTypes;
if (!event.isAnonymous())
define(indexedArgs.emplace_back(m_context.newYulVariable(), *TypeProvider::uint256())) <<
formatNumber(u256(h256::Arith(keccak256(functionType->externalSignature())))) << "\n";
for (size_t i = 0; i < event.parameters().size(); ++i)
{
Expression const& arg = *arguments[i];
if (event.parameters()[i]->isIndexed())
{
string value;
if (auto const& referenceType = dynamic_cast<ReferenceType const*>(paramTypes[i]))
define(indexedArgs.emplace_back(m_context.newYulVariable(), *TypeProvider::uint256())) <<
m_utils.packedHashFunction({arg.annotation().type}, {referenceType}) <<
"(" <<
IRVariable(arg).commaSeparatedList() <<
")";
else
indexedArgs.emplace_back(convert(arg, *paramTypes[i]));
}
else
{
string vars = IRVariable(arg).commaSeparatedList();
if (!vars.empty())
// In reverse because abi_encode expects it like that.
nonIndexedArgs = ", " + move(vars) + nonIndexedArgs;
nonIndexedArgTypes.push_back(arg.annotation().type);
nonIndexedParamTypes.push_back(paramTypes[i]);
}
}
solAssert(indexedArgs.size() <= 4, "Too many indexed arguments.");
Whiskers templ(R"({
let <pos> := <freeMemory>
let <end> := <encode>(<pos> <nonIndexedArgs>)
<log>(<pos>, sub(<end>, <pos>) <indexedArgs>)
})");
templ("pos", m_context.newYulVariable());
templ("end", m_context.newYulVariable());
templ("freeMemory", freeMemory());
templ("encode", abi.tupleEncoder(nonIndexedArgTypes, nonIndexedParamTypes));
templ("nonIndexedArgs", nonIndexedArgs);
templ("log", "log" + to_string(indexedArgs.size()));
templ("indexedArgs", joinHumanReadablePrefixed(indexedArgs | boost::adaptors::transformed([&](auto const& _arg) {
return _arg.commaSeparatedList();
})));
m_code << templ.render();
break;
}
case FunctionType::Kind::Assert:
case FunctionType::Kind::Require:
{
solAssert(arguments.size() > 0, "Expected at least one parameter for require/assert");
solAssert(arguments.size() <= 2, "Expected no more than two parameters for require/assert");
Type const* messageArgumentType = arguments.size() > 1 ? arguments[1]->annotation().type : nullptr;
string requireOrAssertFunction = m_utils.requireOrAssertFunction(
functionType->kind() == FunctionType::Kind::Assert,
messageArgumentType
);
m_code << move(requireOrAssertFunction) << "(" << IRVariable(*arguments[0]).name();
if (messageArgumentType && messageArgumentType->sizeOnStack() > 0)
m_code << ", " << IRVariable(*arguments[1]).commaSeparatedList();
m_code << ")\n";
break;
}
// Array creation using new
case FunctionType::Kind::ObjectCreation:
{
ArrayType const& arrayType = dynamic_cast<ArrayType const&>(*_functionCall.annotation().type);
solAssert(arguments.size() == 1, "");
IRVariable value = convert(*arguments[0], *TypeProvider::uint256());
define(_functionCall) <<
m_utils.allocateAndInitializeMemoryArrayFunction(arrayType) <<
"(" <<
value.commaSeparatedList() <<
")\n";
break;
}
case FunctionType::Kind::KECCAK256:
{
solAssert(arguments.size() == 1, "");
ArrayType const* arrayType = TypeProvider::bytesMemory();
auto array = convert(*arguments[0], *arrayType);
define(_functionCall) <<
"keccak256(" <<
m_utils.arrayDataAreaFunction(*arrayType) <<
"(" <<
array.commaSeparatedList() <<
"), " <<
m_utils.arrayLengthFunction(*arrayType) <<
"(" <<
array.commaSeparatedList() <<
"))\n";
break;
}
case FunctionType::Kind::ArrayPop:
{
auto const& memberAccessExpression = dynamic_cast<MemberAccess const&>(_functionCall.expression()).expression();
ArrayType const& arrayType = dynamic_cast<ArrayType const&>(*memberAccessExpression.annotation().type);
define(_functionCall) <<
m_utils.storageArrayPopFunction(arrayType) <<
"(" <<
IRVariable(_functionCall.expression()).commaSeparatedList() <<
")\n";
break;
}
case FunctionType::Kind::ArrayPush:
{
auto const& memberAccessExpression = dynamic_cast<MemberAccess const&>(_functionCall.expression()).expression();
ArrayType const& arrayType = dynamic_cast<ArrayType const&>(*memberAccessExpression.annotation().type);
if (arguments.empty())
{
auto slotName = m_context.newYulVariable();
auto offsetName = m_context.newYulVariable();
m_code << "let " << slotName << ", " << offsetName << " := " <<
m_utils.storageArrayPushZeroFunction(arrayType) <<
"(" << IRVariable(_functionCall.expression()).commaSeparatedList() << ")\n";
setLValue(_functionCall, IRLValue{
*arrayType.baseType(),
IRLValue::Storage{
slotName,
offsetName,
}
});
}
else
{
IRVariable argument = convert(*arguments.front(), *arrayType.baseType());
m_code <<
m_utils.storageArrayPushFunction(arrayType) <<
"(" <<
IRVariable(_functionCall.expression()).commaSeparatedList() <<
", " <<
argument.commaSeparatedList() <<
")\n";
}
break;
}
default:
solUnimplemented("FunctionKind " + toString(static_cast<int>(functionType->kind())) + " not yet implemented");
}
}
void IRGeneratorForStatements::endVisit(FunctionCallOptions const& _options)
{
FunctionType const& previousType = dynamic_cast<FunctionType const&>(*_options.expression().annotation().type);
solUnimplementedAssert(!previousType.bound(), "");
// Copy over existing values.
for (auto const& item: previousType.stackItems())
define(IRVariable(_options).part(get<0>(item)), IRVariable(_options.expression()).part(get<0>(item)));
for (size_t i = 0; i < _options.names().size(); ++i)
{
string const& name = *_options.names()[i];
solAssert(name == "salt" || name == "gas" || name == "value", "");
define(IRVariable(_options).part(name), *_options.options()[i]);
}
}
void IRGeneratorForStatements::endVisit(MemberAccess const& _memberAccess)
{
ASTString const& member = _memberAccess.memberName();
if (auto funType = dynamic_cast<FunctionType const*>(_memberAccess.annotation().type))
if (funType->bound())
{
solUnimplementedAssert(false, "");
}
switch (_memberAccess.expression().annotation().type->category())
{
case Type::Category::Contract:
{
ContractType const& type = dynamic_cast<ContractType const&>(*_memberAccess.expression().annotation().type);
if (type.isSuper())
{
solUnimplementedAssert(false, "");
}
// ordinary contract type
else if (Declaration const* declaration = _memberAccess.annotation().referencedDeclaration)
{
u256 identifier;
if (auto const* variable = dynamic_cast<VariableDeclaration const*>(declaration))
identifier = FunctionType(*variable).externalIdentifier();
else if (auto const* function = dynamic_cast<FunctionDefinition const*>(declaration))
identifier = FunctionType(*function).externalIdentifier();
else
solAssert(false, "Contract member is neither variable nor function.");
define(IRVariable(_memberAccess).part("address"), _memberAccess.expression());
define(IRVariable(_memberAccess).part("functionIdentifier")) << formatNumber(identifier) << "\n";
}
else
solAssert(false, "Invalid member access in contract");
break;
}
case Type::Category::Integer:
{
solAssert(false, "Invalid member access to integer");
break;
}
case Type::Category::Address:
{
if (member == "balance")
define(_memberAccess) <<
"balance(" <<
expressionAsType(_memberAccess.expression(), *TypeProvider::address()) <<
")\n";
else if (set<string>{"send", "transfer"}.count(member))
{
solAssert(dynamic_cast<AddressType const&>(*_memberAccess.expression().annotation().type).stateMutability() == StateMutability::Payable, "");
define(IRVariable{_memberAccess}.part("address"), _memberAccess.expression());
}
else if (set<string>{"call", "callcode", "delegatecall", "staticcall"}.count(member))
define(IRVariable{_memberAccess}.part("address"), _memberAccess.expression());
else
solAssert(false, "Invalid member access to address");
break;
}
case Type::Category::Function:
if (member == "selector")
{
solUnimplementedAssert(
dynamic_cast<FunctionType const&>(*_memberAccess.expression().annotation().type).kind() ==
FunctionType::Kind::External, ""
);
define(IRVariable{_memberAccess}, IRVariable(_memberAccess.expression()).part("functionIdentifier"));
}
else if (member == "address")
{
solUnimplementedAssert(
dynamic_cast<FunctionType const&>(*_memberAccess.expression().annotation().type).kind() ==
FunctionType::Kind::External, ""
);
define(IRVariable{_memberAccess}, IRVariable(_memberAccess.expression()).part("address"));
}
else
solAssert(
!!_memberAccess.expression().annotation().type->memberType(member),
"Invalid member access to function."
);
break;
case Type::Category::Magic:
// we can ignore the kind of magic and only look at the name of the member
if (member == "coinbase")
define(_memberAccess) << "coinbase()\n";
else if (member == "timestamp")
define(_memberAccess) << "timestamp()\n";
else if (member == "difficulty")
define(_memberAccess) << "difficulty()\n";
else if (member == "number")
define(_memberAccess) << "number()\n";
else if (member == "gaslimit")
define(_memberAccess) << "gaslimit()\n";
else if (member == "sender")
define(_memberAccess) << "caller()\n";
else if (member == "value")
define(_memberAccess) << "callvalue()\n";
else if (member == "origin")
define(_memberAccess) << "origin()\n";
else if (member == "gasprice")
define(_memberAccess) << "gasprice()\n";
else if (member == "data")
{
IRVariable var(_memberAccess);
declare(var);
define(var.part("offset")) << "0\n";
define(var.part("length")) << "calldatasize()\n";
}
else if (member == "sig")
define(_memberAccess) <<
"and(calldataload(0), " <<
formatNumber(u256(0xffffffff) << (256 - 32)) <<
")\n";
else if (member == "gas")
solAssert(false, "Gas has been removed.");
else if (member == "blockhash")
solAssert(false, "Blockhash has been removed.");
else if (member == "creationCode" || member == "runtimeCode")
{
solUnimplementedAssert(false, "");
}
else if (member == "name")
{
solUnimplementedAssert(false, "");
}
else if (set<string>{"encode", "encodePacked", "encodeWithSelector", "encodeWithSignature", "decode"}.count(member))
{
// no-op
}
else
solAssert(false, "Unknown magic member.");
break;
case Type::Category::Struct:
{
solUnimplementedAssert(false, "");
}
case Type::Category::Enum:
{
EnumType const& type = dynamic_cast<EnumType const&>(*_memberAccess.expression().annotation().type);
define(_memberAccess) << to_string(type.memberValue(_memberAccess.memberName())) << "\n";
break;
}
case Type::Category::Array:
{
auto const& type = dynamic_cast<ArrayType const&>(*_memberAccess.expression().annotation().type);
if (member == "length")
{
if (!type.isDynamicallySized())
define(_memberAccess) << type.length() << "\n";
else
switch (type.location())
{
case DataLocation::CallData:
define(_memberAccess, IRVariable(_memberAccess.expression()).part("length"));
break;
case DataLocation::Storage:
{
define(_memberAccess) <<
m_utils.arrayLengthFunction(type) <<
"(" <<
IRVariable(_memberAccess.expression()).commaSeparatedList() <<
")\n";
break;
}
case DataLocation::Memory:
define(_memberAccess) <<
"mload(" <<
IRVariable(_memberAccess.expression()).commaSeparatedList() <<
")\n";
break;
}
}
else if (member == "pop" || member == "push")
{
solAssert(type.location() == DataLocation::Storage, "");
define(IRVariable{_memberAccess}.part("slot"), IRVariable{_memberAccess.expression()}.part("slot"));
}
else
solAssert(false, "Invalid array member access.");
break;
}
case Type::Category::FixedBytes:
{
auto const& type = dynamic_cast<FixedBytesType const&>(*_memberAccess.expression().annotation().type);
if (member == "length")
define(_memberAccess) << to_string(type.numBytes()) << "\n";
else
solAssert(false, "Illegal fixed bytes member.");
break;
}
default:
solAssert(false, "Member access to unknown type.");
}
}
bool IRGeneratorForStatements::visit(InlineAssembly const& _inlineAsm)
{
CopyTranslate bodyCopier{_inlineAsm.dialect(), m_context, _inlineAsm.annotation().externalReferences};
yul::Statement modified = bodyCopier(_inlineAsm.operations());
solAssert(holds_alternative<yul::Block>(modified), "");
// Do not provide dialect so that we get the full type information.
m_code << yul::AsmPrinter()(std::get<yul::Block>(std::move(modified))) << "\n";
return false;
}
void IRGeneratorForStatements::endVisit(IndexAccess const& _indexAccess)
{
Type const& baseType = *_indexAccess.baseExpression().annotation().type;
if (baseType.category() == Type::Category::Mapping)
{
solAssert(_indexAccess.indexExpression(), "Index expression expected.");
MappingType const& mappingType = dynamic_cast<MappingType const&>(baseType);
Type const& keyType = *_indexAccess.indexExpression()->annotation().type;
solAssert(keyType.sizeOnStack() <= 1, "");
string slot = m_context.newYulVariable();
Whiskers templ("let <slot> := <indexAccess>(<base> <key>)\n");
templ("slot", slot);
templ("indexAccess", m_utils.mappingIndexAccessFunction(mappingType, keyType));
templ("base", IRVariable(_indexAccess.baseExpression()).commaSeparatedList());
if (keyType.sizeOnStack() == 0)
templ("key", "");
else
templ("key", ", " + IRVariable(*_indexAccess.indexExpression()).commaSeparatedList());
m_code << templ.render();
setLValue(_indexAccess, IRLValue{
*_indexAccess.annotation().type,
IRLValue::Storage{
slot,
0u
}
});
}
else if (baseType.category() == Type::Category::Array || baseType.category() == Type::Category::ArraySlice)
{
ArrayType const& arrayType =
baseType.category() == Type::Category::Array ?
dynamic_cast<ArrayType const&>(baseType) :
dynamic_cast<ArraySliceType const&>(baseType).arrayType();
if (baseType.category() == Type::Category::ArraySlice)
solAssert(arrayType.dataStoredIn(DataLocation::CallData) && arrayType.isDynamicallySized(), "");
solAssert(_indexAccess.indexExpression(), "Index expression expected.");
switch (arrayType.location())
{
case DataLocation::Storage:
{
string slot = m_context.newYulVariable();
string offset = m_context.newYulVariable();
m_code << Whiskers(R"(
let <slot>, <offset> := <indexFunc>(<array>, <index>)
)")
("slot", slot)
("offset", offset)
("indexFunc", m_utils.storageArrayIndexAccessFunction(arrayType))
("array", IRVariable(_indexAccess.baseExpression()).part("slot").name())
("index", IRVariable(*_indexAccess.indexExpression()).name())
.render();
setLValue(_indexAccess, IRLValue{
*_indexAccess.annotation().type,
IRLValue::Storage{slot, offset}
});
break;
}
case DataLocation::Memory:
{
string const memAddress =
m_utils.memoryArrayIndexAccessFunction(arrayType) +
"(" +
IRVariable(_indexAccess.baseExpression()).part("mpos").name() +
", " +
expressionAsType(*_indexAccess.indexExpression(), *TypeProvider::uint256()) +
")";
setLValue(_indexAccess, IRLValue{
*arrayType.baseType(),
IRLValue::Memory{memAddress}
});
break;
}
case DataLocation::CallData:
{
IRVariable var(m_context.newYulVariable(), *arrayType.baseType());
define(var) <<
m_utils.calldataArrayIndexAccessFunction(arrayType) <<
"(" <<
IRVariable(_indexAccess.baseExpression()).commaSeparatedList() <<
", " <<
expressionAsType(*_indexAccess.indexExpression(), *TypeProvider::uint256()) <<
")\n";
if (arrayType.isByteArray())
define(_indexAccess) <<
m_utils.cleanupFunction(*arrayType.baseType()) <<
"(calldataload(" <<
var.name() <<
"))\n";
else if (arrayType.baseType()->isValueType())
define(_indexAccess) <<
m_utils.readFromCalldata(*arrayType.baseType()) <<
"(" <<
var.commaSeparatedList() <<
")\n";
else
define(_indexAccess, var);
break;
}
}
}
else if (baseType.category() == Type::Category::FixedBytes)
solUnimplementedAssert(false, "");
else if (baseType.category() == Type::Category::TypeType)
{
solAssert(baseType.sizeOnStack() == 0, "");
solAssert(_indexAccess.annotation().type->sizeOnStack() == 0, "");
// no-op - this seems to be a lone array type (`structType[];`)
}
else
solAssert(false, "Index access only allowed for mappings or arrays.");
}
void IRGeneratorForStatements::endVisit(IndexRangeAccess const& _indexRangeAccess)
{
Type const& baseType = *_indexRangeAccess.baseExpression().annotation().type;
solAssert(
baseType.category() == Type::Category::Array || baseType.category() == Type::Category::ArraySlice,
"Index range accesses is available only on arrays and array slices."
);
ArrayType const& arrayType =
baseType.category() == Type::Category::Array ?
dynamic_cast<ArrayType const &>(baseType) :
dynamic_cast<ArraySliceType const &>(baseType).arrayType();
switch (arrayType.location())
{
case DataLocation::CallData:
{
solAssert(baseType.isDynamicallySized(), "");
IRVariable sliceStart{m_context.newYulVariable(), *TypeProvider::uint256()};
if (_indexRangeAccess.startExpression())
define(sliceStart, IRVariable{*_indexRangeAccess.startExpression()});
else
define(sliceStart) << u256(0) << "\n";
IRVariable sliceEnd{
m_context.newYulVariable(),
*TypeProvider::uint256()
};
if (_indexRangeAccess.endExpression())
define(sliceEnd, IRVariable{*_indexRangeAccess.endExpression()});
else
define(sliceEnd, IRVariable{_indexRangeAccess.baseExpression()}.part("length"));
IRVariable range{_indexRangeAccess};
define(range) <<
m_utils.calldataArrayIndexRangeAccess(arrayType) << "(" <<
IRVariable{_indexRangeAccess.baseExpression()}.commaSeparatedList() << ", " <<
sliceStart.name() << ", " <<
sliceEnd.name() << ")\n";
break;
}
default:
solUnimplementedAssert(false, "Index range accesses is implemented only on calldata arrays.");
}
}
void IRGeneratorForStatements::endVisit(Identifier const& _identifier)
{
Declaration const* declaration = _identifier.annotation().referencedDeclaration;
if (MagicVariableDeclaration const* magicVar = dynamic_cast<MagicVariableDeclaration const*>(declaration))
{
switch (magicVar->type()->category())
{
case Type::Category::Contract:
if (dynamic_cast<ContractType const&>(*magicVar->type()).isSuper())
solAssert(_identifier.name() == "super", "");
else
{
solAssert(_identifier.name() == "this", "");
define(_identifier) << "address()\n";
}
break;
case Type::Category::Integer:
solAssert(_identifier.name() == "now", "");
define(_identifier) << "timestamp()\n";
break;
default:
break;
}
return;
}
else if (FunctionDefinition const* functionDef = dynamic_cast<FunctionDefinition const*>(declaration))
define(_identifier) << to_string(functionDef->resolveVirtual(m_context.mostDerivedContract()).id()) << "\n";
else if (VariableDeclaration const* varDecl = dynamic_cast<VariableDeclaration const*>(declaration))
{
// TODO for the constant case, we have to be careful:
// If the value is visited twice, `defineExpression` is called twice on
// the same expression.
solUnimplementedAssert(!varDecl->isConstant(), "");
solUnimplementedAssert(!varDecl->immutable(), "");
if (m_context.isLocalVariable(*varDecl))
setLValue(_identifier, IRLValue{
*varDecl->annotation().type,
IRLValue::Stack{m_context.localVariable(*varDecl)}
});
else if (m_context.isStateVariable(*varDecl))
setLValue(_identifier, IRLValue{
*varDecl->annotation().type,
IRLValue::Storage{
toCompactHexWithPrefix(m_context.storageLocationOfVariable(*varDecl).first),
m_context.storageLocationOfVariable(*varDecl).second
}
});
else
solAssert(false, "Invalid variable kind.");
}
else if (auto contract = dynamic_cast<ContractDefinition const*>(declaration))
{
solUnimplementedAssert(!contract->isLibrary(), "Libraries not yet supported.");
}
else if (dynamic_cast<EventDefinition const*>(declaration))
{
// no-op
}
else if (dynamic_cast<EnumDefinition const*>(declaration))
{
// no-op
}
else if (dynamic_cast<StructDefinition const*>(declaration))
{
// no-op
}
else
{
solAssert(false, "Identifier type not expected in expression context.");
}
}
bool IRGeneratorForStatements::visit(Literal const& _literal)
{
Type const& literalType = type(_literal);
switch (literalType.category())
{
case Type::Category::RationalNumber:
case Type::Category::Bool:
case Type::Category::Address:
define(_literal) << toCompactHexWithPrefix(literalType.literalValue(&_literal)) << "\n";
break;
case Type::Category::StringLiteral:
break; // will be done during conversion
default:
solUnimplemented("Only integer, boolean and string literals implemented for now.");
}
return false;
}
void IRGeneratorForStatements::appendExternalFunctionCall(
FunctionCall const& _functionCall,
vector<ASTPointer<Expression const>> const& _arguments
)
{
FunctionType const& funType = dynamic_cast<FunctionType const&>(type(_functionCall.expression()));
solAssert(
funType.takesArbitraryParameters() ||
_arguments.size() == funType.parameterTypes().size(), ""
);
solUnimplementedAssert(!funType.bound(), "");
FunctionType::Kind const funKind = funType.kind();
solAssert(funKind != FunctionType::Kind::BareStaticCall || m_context.evmVersion().hasStaticCall(), "");
solAssert(funKind != FunctionType::Kind::BareCallCode, "Callcode has been removed.");
bool const isDelegateCall = funKind == FunctionType::Kind::BareDelegateCall || funKind == FunctionType::Kind::DelegateCall;
bool const useStaticCall = funKind == FunctionType::Kind::BareStaticCall || (funType.stateMutability() <= StateMutability::View && m_context.evmVersion().hasStaticCall());
ReturnInfo const returnInfo{m_context.evmVersion(), funType};
TypePointers argumentTypes;
vector<string> argumentStrings;
for (auto const& arg: _arguments)
{
argumentTypes.emplace_back(&type(*arg));
argumentStrings.emplace_back(IRVariable(*arg).commaSeparatedList());
}
string argumentString = argumentStrings.empty() ? ""s : (", " + joinHumanReadable(argumentStrings));
solUnimplementedAssert(funKind != FunctionType::Kind::ECRecover, "");
if (!m_context.evmVersion().canOverchargeGasForCall())
{
// Touch the end of the output area so that we do not pay for memory resize during the call
// (which we would have to subtract from the gas left)
// We could also just use MLOAD; POP right before the gas calculation, but the optimizer
// would remove that, so we use MSTORE here.
if (!funType.gasSet() && returnInfo.estimatedReturnSize > 0)
m_code << "mstore(add(" << freeMemory() << ", " << to_string(returnInfo.estimatedReturnSize) << "), 0)\n";
}
ABIFunctions abi(m_context.evmVersion(), m_context.revertStrings(), m_context.functionCollector());
solUnimplementedAssert(!funType.isBareCall(), "");
Whiskers templ(R"(
<?checkExistence>
if iszero(extcodesize(<address>)) { revert(0, 0) }
</checkExistence>
// storage for arguments and returned data
let <pos> := <freeMemory>
mstore(<pos>, <shl28>(<funId>))
let <end> := <encodeArgs>(add(<pos>, 4) <argumentString>)
let <success> := <call>(<gas>, <address>, <?hasValue> <value>, </hasValue> <pos>, sub(<end>, <pos>), <pos>, <reservedReturnSize>)
<?noTryCall>
if iszero(<success>) { <forwardingRevert>() }
</noTryCall>
<?hasRetVars> let <retVars> </hasRetVars>
if <success> {
<?dynamicReturnSize>
// copy dynamic return data out
returndatacopy(<pos>, 0, returndatasize())
</dynamicReturnSize>
// update freeMemoryPointer according to dynamic return size
mstore(<freeMemoryPointer>, add(<pos>, <roundUp>(<returnSize>)))
// decode return parameters from external try-call into retVars
<?hasRetVars> <retVars> := </hasRetVars> <abiDecode>(<pos>, add(<pos>, <returnSize>))
}
)");
templ("pos", m_context.newYulVariable());
templ("end", m_context.newYulVariable());
if (_functionCall.annotation().tryCall)
templ("success", m_context.trySuccessConditionVariable(_functionCall));
else
templ("success", m_context.newYulVariable());
templ("freeMemory", freeMemory());
templ("shl28", m_utils.shiftLeftFunction(8 * (32 - 4)));
templ("funId", IRVariable(_functionCall.expression()).part("functionIdentifier").name());
templ("address", IRVariable(_functionCall.expression()).part("address").name());
// Always use the actual return length, and not our calculated expected length, if returndatacopy is supported.
// This ensures it can catch badly formatted input from external calls.
if (m_context.evmVersion().supportsReturndata())
templ("returnSize", "returndatasize()");
else
templ("returnSize", to_string(returnInfo.estimatedReturnSize));
templ("reservedReturnSize", returnInfo.dynamicReturnSize ? "0" : to_string(returnInfo.estimatedReturnSize));
string const retVars = IRVariable(_functionCall).commaSeparatedList();
templ("retVars", retVars);
templ("hasRetVars", !retVars.empty());
solAssert(retVars.empty() == returnInfo.returnTypes.empty(), "");
templ("roundUp", m_utils.roundUpFunction());
templ("abiDecode", abi.tupleDecoder(returnInfo.returnTypes, true));
templ("dynamicReturnSize", returnInfo.dynamicReturnSize);
templ("freeMemoryPointer", to_string(CompilerUtils::freeMemoryPointer));
templ("noTryCall", !_functionCall.annotation().tryCall);
// If the function takes arbitrary parameters or is a bare call, copy dynamic length data in place.
// Move arguments to memory, will not update the free memory pointer (but will update the memory
// pointer on the stack).
bool encodeInPlace = funType.takesArbitraryParameters() || funType.isBareCall();
if (funType.kind() == FunctionType::Kind::ECRecover)
// This would be the only combination of padding and in-place encoding,
// but all parameters of ecrecover are value types anyway.
encodeInPlace = false;
bool encodeForLibraryCall = funKind == FunctionType::Kind::DelegateCall;
solUnimplementedAssert(!encodeInPlace, "");
solUnimplementedAssert(funType.padArguments(), "");
templ("encodeArgs", abi.tupleEncoder(argumentTypes, funType.parameterTypes(), encodeForLibraryCall));
templ("argumentString", argumentString);
// Output data will replace input data, unless we have ECRecover (then, output
// area will be 32 bytes just before input area).
solUnimplementedAssert(funKind != FunctionType::Kind::ECRecover, "");
solAssert(!isDelegateCall || !funType.valueSet(), "Value set for delegatecall");
solAssert(!useStaticCall || !funType.valueSet(), "Value set for staticcall");
templ("hasValue", !isDelegateCall && !useStaticCall);
templ("value", funType.valueSet() ? IRVariable(_functionCall.expression()).part("value").name() : "0");
// Check that the target contract exists (has code) for non-low-level calls.
bool checkExistence = (funKind == FunctionType::Kind::External || funKind == FunctionType::Kind::DelegateCall);
templ("checkExistence", checkExistence);
if (funType.gasSet())
templ("gas", IRVariable(_functionCall.expression()).part("gas").name());
else if (m_context.evmVersion().canOverchargeGasForCall())
// Send all gas (requires tangerine whistle EVM)
templ("gas", "gas()");
else
{
// send all gas except the amount needed to execute "SUB" and "CALL"
// @todo this retains too much gas for now, needs to be fine-tuned.
u256 gasNeededByCaller = evmasm::GasCosts::callGas(m_context.evmVersion()) + 10;
if (funType.valueSet())
gasNeededByCaller += evmasm::GasCosts::callValueTransferGas;
if (!checkExistence)
gasNeededByCaller += evmasm::GasCosts::callNewAccountGas; // we never know
templ("gas", "sub(gas(), " + formatNumber(gasNeededByCaller) + ")");
}
// Order is important here, STATICCALL might overlap with DELEGATECALL.
if (isDelegateCall)
templ("call", "delegatecall");
else if (useStaticCall)
templ("call", "staticcall");
else
templ("call", "call");
templ("forwardingRevert", m_utils.forwardingRevertFunction());
solUnimplementedAssert(funKind != FunctionType::Kind::RIPEMD160, "");
solUnimplementedAssert(funKind != FunctionType::Kind::ECRecover, "");
m_code << templ.render();
}
string IRGeneratorForStatements::freeMemory()
{
return "mload(" + to_string(CompilerUtils::freeMemoryPointer) + ")";
}
IRVariable IRGeneratorForStatements::convert(IRVariable const& _from, Type const& _to)
{
if (_from.type() == _to)
return _from;
else
{
IRVariable converted(m_context.newYulVariable(), _to);
define(converted, _from);
return converted;
}
}
std::string IRGeneratorForStatements::expressionAsType(Expression const& _expression, Type const& _to)
{
IRVariable from(_expression);
if (from.type() == _to)
return from.commaSeparatedList();
else
return m_utils.conversionFunction(from.type(), _to) + "(" + from.commaSeparatedList() + ")";
}
std::ostream& IRGeneratorForStatements::define(IRVariable const& _var)
{
if (_var.type().sizeOnStack() > 0)
m_code << "let " << _var.commaSeparatedList() << " := ";
return m_code;
}
void IRGeneratorForStatements::declare(IRVariable const& _var)
{
if (_var.type().sizeOnStack() > 0)
m_code << "let " << _var.commaSeparatedList() << "\n";
}
void IRGeneratorForStatements::declareAssign(IRVariable const& _lhs, IRVariable const& _rhs, bool _declare)
{
string output;
if (_lhs.type() == _rhs.type())
for (auto const& [stackItemName, stackItemType]: _lhs.type().stackItems())
if (stackItemType)
declareAssign(_lhs.part(stackItemName), _rhs.part(stackItemName), _declare);
else
m_code << (_declare ? "let ": "") << _lhs.part(stackItemName).name() << " := " << _rhs.part(stackItemName).name() << "\n";
else
{
if (_lhs.type().sizeOnStack() > 0)
m_code <<
(_declare ? "let ": "") <<
_lhs.commaSeparatedList() <<
" := ";
m_code << m_context.utils().conversionFunction(_rhs.type(), _lhs.type()) <<
"(" <<
_rhs.commaSeparatedList() <<
")\n";
}
}
IRVariable IRGeneratorForStatements::zeroValue(Type const& _type, bool _splitFunctionTypes)
{
IRVariable irVar{
"zero_value_for_type_" + _type.identifier() + m_context.newYulVariable(),
_type
};
define(irVar) << m_utils.zeroValueFunction(_type, _splitFunctionTypes) << "()\n";
return irVar;
}
void IRGeneratorForStatements::appendSimpleUnaryOperation(UnaryOperation const& _operation, Expression const& _expr)
{
string func;
if (_operation.getOperator() == Token::Not)
func = "iszero";
else if (_operation.getOperator() == Token::BitNot)
func = "not";
else
solAssert(false, "Invalid Token!");
define(_operation) <<
m_utils.cleanupFunction(type(_expr)) <<
"(" <<
func <<
"(" <<
IRVariable(_expr).commaSeparatedList() <<
")" <<
")\n";
}
string IRGeneratorForStatements::binaryOperation(
langutil::Token _operator,
Type const& _type,
string const& _left,
string const& _right
)
{
if (IntegerType const* type = dynamic_cast<IntegerType const*>(&_type))
{
string fun;
// TODO: Implement all operations for signed and unsigned types.
switch (_operator)
{
case Token::Add:
fun = m_utils.overflowCheckedIntAddFunction(*type);
break;
case Token::Sub:
fun = m_utils.overflowCheckedIntSubFunction(*type);
break;
case Token::Mul:
fun = m_utils.overflowCheckedIntMulFunction(*type);
break;
case Token::Div:
fun = m_utils.overflowCheckedIntDivFunction(*type);
break;
case Token::Mod:
fun = m_utils.checkedIntModFunction(*type);
break;
case Token::BitOr:
fun = "or";
break;
case Token::BitXor:
fun = "xor";
break;
case Token::BitAnd:
fun = "and";
break;
default:
break;
}
solUnimplementedAssert(!fun.empty(), "");
return fun + "(" + _left + ", " + _right + ")\n";
}
else
solUnimplementedAssert(false, "");
return {};
}
void IRGeneratorForStatements::appendAndOrOperatorCode(BinaryOperation const& _binOp)
{
langutil::Token const op = _binOp.getOperator();
solAssert(op == Token::Or || op == Token::And, "");
_binOp.leftExpression().accept(*this);
IRVariable value(_binOp);
define(value, _binOp.leftExpression());
if (op == Token::Or)
m_code << "if iszero(" << value.name() << ") {\n";
else
m_code << "if " << value.name() << " {\n";
_binOp.rightExpression().accept(*this);
assign(value, _binOp.rightExpression());
m_code << "}\n";
}
void IRGeneratorForStatements::writeToLValue(IRLValue const& _lvalue, IRVariable const& _value)
{
std::visit(
util::GenericVisitor{
[&](IRLValue::Storage const& _storage) {
std::optional<unsigned> offset;
if (std::holds_alternative<unsigned>(_storage.offset))
offset = std::get<unsigned>(_storage.offset);
m_code <<
m_utils.updateStorageValueFunction(_lvalue.type, offset) <<
"(" <<
_storage.slot <<
(
std::holds_alternative<string>(_storage.offset) ?
(", " + std::get<string>(_storage.offset)) :
""
) <<
_value.commaSeparatedListPrefixed() <<
")\n";
},
[&](IRLValue::Memory const& _memory) {
if (_lvalue.type.isValueType())
{
IRVariable prepared(m_context.newYulVariable(), _lvalue.type);
define(prepared, _value);
if (_memory.byteArrayElement)
{
solAssert(_lvalue.type == *TypeProvider::byte(), "");
m_code << "mstore8(" + _memory.address + ", byte(0, " + prepared.commaSeparatedList() + "))\n";
}
else
m_code << m_utils.writeToMemoryFunction(_lvalue.type) <<
"(" <<
_memory.address <<
", " <<
prepared.commaSeparatedList() <<
")\n";
}
else
{
solAssert(_lvalue.type.sizeOnStack() == 1, "");
solAssert(dynamic_cast<ReferenceType const*>(&_lvalue.type), "");
auto const* valueReferenceType = dynamic_cast<ReferenceType const*>(&_value.type());
solAssert(valueReferenceType && valueReferenceType->dataStoredIn(DataLocation::Memory), "");
m_code << "mstore(" + _memory.address + ", " + _value.part("mpos").name() + ")\n";
}
},
[&](IRLValue::Stack const& _stack) { assign(_stack.variable, _value); },
[&](IRLValue::Tuple const& _tuple) {
auto components = std::move(_tuple.components);
for (size_t i = 0; i < components.size(); i++)
{
size_t idx = components.size() - i - 1;
if (components[idx])
writeToLValue(*components[idx], _value.tupleComponent(idx));
}
}
},
_lvalue.kind
);
}
IRVariable IRGeneratorForStatements::readFromLValue(IRLValue const& _lvalue)
{
IRVariable result{m_context.newYulVariable(), _lvalue.type};
std::visit(GenericVisitor{
[&](IRLValue::Storage const& _storage) {
if (!_lvalue.type.isValueType())
define(result) << _storage.slot << "\n";
else if (std::holds_alternative<string>(_storage.offset))
define(result) <<
m_utils.readFromStorageDynamic(_lvalue.type, false) <<
"(" <<
_storage.slot <<
", " <<
std::get<string>(_storage.offset) <<
")\n";
else
define(result) <<
m_utils.readFromStorage(_lvalue.type, std::get<unsigned>(_storage.offset), false) <<
"(" <<
_storage.slot <<
")\n";
},
[&](IRLValue::Memory const& _memory) {
if (_memory.byteArrayElement)
define(result) <<
m_utils.cleanupFunction(_lvalue.type) <<
"(mload(" <<
_memory.address <<
"))\n";
else if (_lvalue.type.isValueType())
define(result) <<
m_utils.readFromMemory(_lvalue.type) <<
"(" <<
_memory.address <<
")\n";
else
define(result) << "mload(" << _memory.address << ")\n";
},
[&](IRLValue::Stack const& _stack) {
define(result, _stack.variable);
},
[&](IRLValue::Tuple const&) {
solAssert(false, "Attempted to read from tuple lvalue.");
}
}, _lvalue.kind);
return result;
}
void IRGeneratorForStatements::setLValue(Expression const& _expression, IRLValue _lvalue)
{
solAssert(!m_currentLValue, "");
if (_expression.annotation().lValueRequested)
{
m_currentLValue.emplace(std::move(_lvalue));
solAssert(!_lvalue.type.dataStoredIn(DataLocation::CallData), "");
}
else
// Only define the expression, if it will not be written to.
define(_expression, readFromLValue(_lvalue));
}
void IRGeneratorForStatements::generateLoop(
Statement const& _body,
Expression const* _conditionExpression,
Statement const* _initExpression,
ExpressionStatement const* _loopExpression,
bool _isDoWhile
)
{
string firstRun;
if (_isDoWhile)
{
solAssert(_conditionExpression, "Expected condition for doWhile");
firstRun = m_context.newYulVariable();
m_code << "let " << firstRun << " := 1\n";
}
m_code << "for {\n";
if (_initExpression)
_initExpression->accept(*this);
m_code << "} 1 {\n";
if (_loopExpression)
_loopExpression->accept(*this);
m_code << "}\n";
m_code << "{\n";
if (_conditionExpression)
{
if (_isDoWhile)
m_code << "if iszero(" << firstRun << ") {\n";
_conditionExpression->accept(*this);
m_code <<
"if iszero(" <<
expressionAsType(*_conditionExpression, *TypeProvider::boolean()) <<
") { break }\n";
if (_isDoWhile)
m_code << "}\n" << firstRun << " := 0\n";
}
_body.accept(*this);
m_code << "}\n";
}
Type const& IRGeneratorForStatements::type(Expression const& _expression)
{
solAssert(_expression.annotation().type, "Type of expression not set.");
return *_expression.annotation().type;
}
bool IRGeneratorForStatements::visit(TryStatement const& _tryStatement)
{
Expression const& externalCall = _tryStatement.externalCall();
externalCall.accept(*this);
m_code << "switch iszero(" << m_context.trySuccessConditionVariable(externalCall) << ")\n";
m_code << "case 0 { // success case\n";
TryCatchClause const& successClause = *_tryStatement.clauses().front();
if (successClause.parameters())
{
size_t i = 0;
for (ASTPointer<VariableDeclaration> const& varDecl: successClause.parameters()->parameters())
{
solAssert(varDecl, "");
define(m_context.addLocalVariable(*varDecl),
successClause.parameters()->parameters().size() == 1 ?
IRVariable(externalCall) :
IRVariable(externalCall).tupleComponent(i++)
);
}
}
successClause.block().accept(*this);
m_code << "}\n";
m_code << "default { // failure case\n";
handleCatch(_tryStatement);
m_code << "}\n";
return false;
}
void IRGeneratorForStatements::handleCatch(TryStatement const& _tryStatement)
{
if (_tryStatement.structuredClause())
handleCatchStructuredAndFallback(*_tryStatement.structuredClause(), _tryStatement.fallbackClause());
else if (_tryStatement.fallbackClause())
handleCatchFallback(*_tryStatement.fallbackClause());
else
rethrow();
}
void IRGeneratorForStatements::handleCatchStructuredAndFallback(
TryCatchClause const& _structured,
TryCatchClause const* _fallback
)
{
solAssert(
_structured.parameters() &&
_structured.parameters()->parameters().size() == 1 &&
_structured.parameters()->parameters().front() &&
*_structured.parameters()->parameters().front()->annotation().type == *TypeProvider::stringMemory(),
""
);
solAssert(m_context.evmVersion().supportsReturndata(), "");
// Try to decode the error message.
// If this fails, leaves 0 on the stack, otherwise the pointer to the data string.
string const dataVariable = m_context.newYulVariable();
m_code << "let " << dataVariable << " := " << m_utils.tryDecodeErrorMessageFunction() << "()\n";
m_code << "switch iszero(" << dataVariable << ") \n";
m_code << "case 0 { // decoding success\n";
if (_structured.parameters())
{
solAssert(_structured.parameters()->parameters().size() == 1, "");
IRVariable const& var = m_context.addLocalVariable(*_structured.parameters()->parameters().front());
define(var) << dataVariable << "\n";
}
_structured.accept(*this);
m_code << "}\n";
m_code << "default { // decoding failure\n";
if (_fallback)
handleCatchFallback(*_fallback);
else
rethrow();
m_code << "}\n";
}
void IRGeneratorForStatements::handleCatchFallback(TryCatchClause const& _fallback)
{
if (_fallback.parameters())
{
solAssert(m_context.evmVersion().supportsReturndata(), "");
solAssert(
_fallback.parameters()->parameters().size() == 1 &&
_fallback.parameters()->parameters().front() &&
*_fallback.parameters()->parameters().front()->annotation().type == *TypeProvider::bytesMemory(),
""
);
VariableDeclaration const& paramDecl = *_fallback.parameters()->parameters().front();
define(m_context.addLocalVariable(paramDecl)) << m_utils.extractReturndataFunction() << "()\n";
}
_fallback.accept(*this);
}
void IRGeneratorForStatements::rethrow()
{
if (m_context.evmVersion().supportsReturndata())
m_code << R"(
returndatacopy(0, 0, returndatasize())
revert(0, returndatasize())
)"s;
else
m_code << "revert(0, 0) // rethrow\n"s;
}
bool IRGeneratorForStatements::visit(TryCatchClause const& _clause)
{
_clause.block().accept(*this);
return false;
}