solidity/libsolidity/formal/SymbolicVariables.cpp
2023-08-15 14:40:27 +02:00

401 lines
11 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/>.
*/
// SPDX-License-Identifier: GPL-3.0
#include <libsolidity/formal/SymbolicVariables.h>
#include <libsolidity/formal/EncodingContext.h>
#include <libsolidity/formal/SymbolicTypes.h>
#include <libsolutil/Algorithms.h>
using namespace solidity;
using namespace solidity::util;
using namespace solidity::smtutil;
using namespace solidity::frontend;
using namespace solidity::frontend::smt;
SymbolicVariable::SymbolicVariable(
frontend::Type const* _type,
frontend::Type const* _originalType,
std::string _uniqueName,
EncodingContext& _context
):
m_type(_type),
m_originalType(_originalType),
m_uniqueName(std::move(_uniqueName)),
m_context(_context),
m_ssa(std::make_unique<SSAVariable>())
{
solAssert(m_type, "");
m_sort = smtSort(*m_type);
solAssert(m_sort, "");
}
SymbolicVariable::SymbolicVariable(
SortPointer _sort,
std::string _uniqueName,
EncodingContext& _context
):
m_sort(std::move(_sort)),
m_uniqueName(std::move(_uniqueName)),
m_context(_context),
m_ssa(std::make_unique<SSAVariable>())
{
solAssert(m_sort, "");
}
smtutil::Expression SymbolicVariable::currentValue(frontend::Type const*) const
{
return valueAtIndex(m_ssa->index());
}
std::string SymbolicVariable::currentName() const
{
return uniqueSymbol(m_ssa->index());
}
smtutil::Expression SymbolicVariable::valueAtIndex(unsigned _index) const
{
return m_context.newVariable(uniqueSymbol(_index), m_sort);
}
std::string SymbolicVariable::nameAtIndex(unsigned _index) const
{
return uniqueSymbol(_index);
}
std::string SymbolicVariable::uniqueSymbol(unsigned _index) const
{
return m_uniqueName + "_" + std::to_string(_index);
}
smtutil::Expression SymbolicVariable::resetIndex()
{
m_ssa->resetIndex();
return currentValue();
}
smtutil::Expression SymbolicVariable::setIndex(unsigned _index)
{
m_ssa->setIndex(_index);
return currentValue();
}
smtutil::Expression SymbolicVariable::increaseIndex()
{
++(*m_ssa);
return currentValue();
}
SymbolicBoolVariable::SymbolicBoolVariable(
frontend::Type const* _type,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(_type, _type, std::move(_uniqueName), _context)
{
solAssert(m_type->category() == frontend::Type::Category::Bool, "");
}
SymbolicIntVariable::SymbolicIntVariable(
frontend::Type const* _type,
frontend::Type const* _originalType,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(_type, _originalType, std::move(_uniqueName), _context)
{
solAssert(isNumber(*m_type), "");
}
SymbolicAddressVariable::SymbolicAddressVariable(
std::string _uniqueName,
EncodingContext& _context
):
SymbolicIntVariable(TypeProvider::uint(160), TypeProvider::uint(160), std::move(_uniqueName), _context)
{
}
SymbolicFixedBytesVariable::SymbolicFixedBytesVariable(
frontend::Type const* _originalType,
unsigned _numBytes,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicIntVariable(TypeProvider::uint(_numBytes * 8), _originalType, std::move(_uniqueName), _context)
{
}
SymbolicFunctionVariable::SymbolicFunctionVariable(
frontend::Type const* _type,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(_type, _type, std::move(_uniqueName), _context),
m_declaration(m_context.newVariable(currentName(), m_sort))
{
solAssert(m_type->category() == frontend::Type::Category::Function, "");
}
SymbolicFunctionVariable::SymbolicFunctionVariable(
SortPointer _sort,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(std::move(_sort), std::move(_uniqueName), _context),
m_declaration(m_context.newVariable(currentName(), m_sort))
{
solAssert(m_sort->kind == Kind::Function, "");
}
smtutil::Expression SymbolicFunctionVariable::currentValue(frontend::Type const* _targetType) const
{
return m_abstract.currentValue(_targetType);
}
smtutil::Expression SymbolicFunctionVariable::currentFunctionValue() const
{
return m_declaration;
}
smtutil::Expression SymbolicFunctionVariable::valueAtIndex(unsigned _index) const
{
return m_abstract.valueAtIndex(_index);
}
smtutil::Expression SymbolicFunctionVariable::functionValueAtIndex(unsigned _index) const
{
return SymbolicVariable::valueAtIndex(_index);
}
smtutil::Expression SymbolicFunctionVariable::resetIndex()
{
SymbolicVariable::resetIndex();
return m_abstract.resetIndex();
}
smtutil::Expression SymbolicFunctionVariable::setIndex(unsigned _index)
{
SymbolicVariable::setIndex(_index);
return m_abstract.setIndex(_index);
}
smtutil::Expression SymbolicFunctionVariable::increaseIndex()
{
++(*m_ssa);
resetDeclaration();
m_abstract.increaseIndex();
return m_abstract.currentValue();
}
smtutil::Expression SymbolicFunctionVariable::operator()(std::vector<smtutil::Expression> _arguments) const
{
return m_declaration(_arguments);
}
void SymbolicFunctionVariable::resetDeclaration()
{
m_declaration = m_context.newVariable(currentName(), m_sort);
}
SymbolicEnumVariable::SymbolicEnumVariable(
frontend::Type const* _type,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(_type, _type, std::move(_uniqueName), _context)
{
solAssert(isEnum(*m_type), "");
}
SymbolicTupleVariable::SymbolicTupleVariable(
frontend::Type const* _type,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(_type, _type, std::move(_uniqueName), _context)
{
solAssert(isTuple(*m_type), "");
}
SymbolicTupleVariable::SymbolicTupleVariable(
SortPointer _sort,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(std::move(_sort), std::move(_uniqueName), _context)
{
solAssert(m_sort->kind == Kind::Tuple, "");
}
smtutil::Expression SymbolicTupleVariable::currentValue(frontend::Type const* _targetType) const
{
if (!_targetType || sort() == smtSort(*_targetType))
return SymbolicVariable::currentValue();
auto thisTuple = std::dynamic_pointer_cast<TupleSort>(sort());
auto otherTuple = std::dynamic_pointer_cast<TupleSort>(smtSort(*_targetType));
solAssert(thisTuple && otherTuple, "");
solAssert(thisTuple->components.size() == otherTuple->components.size(), "");
std::vector<smtutil::Expression> args;
for (size_t i = 0; i < thisTuple->components.size(); ++i)
args.emplace_back(component(i, type(), _targetType));
return smtutil::Expression::tuple_constructor(
smtutil::Expression(std::make_shared<smtutil::SortSort>(smtSort(*_targetType)), ""),
args
);
}
std::vector<SortPointer> const& SymbolicTupleVariable::components() const
{
auto tupleSort = std::dynamic_pointer_cast<TupleSort>(m_sort);
solAssert(tupleSort, "");
return tupleSort->components;
}
smtutil::Expression SymbolicTupleVariable::component(
size_t _index,
frontend::Type const* _fromType,
frontend::Type const* _toType
) const
{
std::optional<smtutil::Expression> conversion = symbolicTypeConversion(_fromType, _toType);
if (conversion)
return *conversion;
return smtutil::Expression::tuple_get(currentValue(), _index);
}
SymbolicArrayVariable::SymbolicArrayVariable(
frontend::Type const* _type,
frontend::Type const* _originalType,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(_type, _originalType, std::move(_uniqueName), _context),
m_pair(
smtSort(*_type),
m_uniqueName + "_length_pair",
m_context
)
{
solAssert(isArray(*m_type) || isMapping(*m_type), "");
}
SymbolicArrayVariable::SymbolicArrayVariable(
SortPointer _sort,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(std::move(_sort), std::move(_uniqueName), _context),
m_pair(
std::make_shared<TupleSort>(
"array_length_pair",
std::vector<std::string>{"array", "length"},
std::vector<SortPointer>{m_sort, SortProvider::uintSort}
),
m_uniqueName + "_array_length_pair",
m_context
)
{
solAssert(m_sort->kind == Kind::Array, "");
}
smtutil::Expression SymbolicArrayVariable::currentValue(frontend::Type const* _targetType) const
{
std::optional<smtutil::Expression> conversion = symbolicTypeConversion(m_originalType, _targetType);
if (conversion)
return *conversion;
return m_pair.currentValue();
}
smtutil::Expression SymbolicArrayVariable::valueAtIndex(unsigned _index) const
{
return m_pair.valueAtIndex(_index);
}
smtutil::Expression SymbolicArrayVariable::elements() const
{
return m_pair.component(0);
}
smtutil::Expression SymbolicArrayVariable::length() const
{
return m_pair.component(1);
}
SymbolicStructVariable::SymbolicStructVariable(
frontend::Type const* _type,
std::string _uniqueName,
EncodingContext& _context
):
SymbolicVariable(_type, _type, std::move(_uniqueName), _context)
{
solAssert(isNonRecursiveStruct(*m_type), "");
auto const* structType = dynamic_cast<StructType const*>(_type);
solAssert(structType, "");
auto const& members = structType->structDefinition().members();
for (unsigned i = 0; i < members.size(); ++i)
{
solAssert(members.at(i), "");
m_memberIndices.emplace(members.at(i)->name(), i);
}
}
smtutil::Expression SymbolicStructVariable::member(std::string const& _member) const
{
return smtutil::Expression::tuple_get(currentValue(), m_memberIndices.at(_member));
}
smtutil::Expression SymbolicStructVariable::assignMember(std::string const& _member, smtutil::Expression const& _memberValue)
{
auto const* structType = dynamic_cast<StructType const*>(m_type);
solAssert(structType, "");
auto const& structDef = structType->structDefinition();
auto const& structMembers = structDef.members();
auto oldMembers = applyMap(
structMembers,
[&](auto _member) { return member(_member->name()); }
);
increaseIndex();
for (unsigned i = 0; i < structMembers.size(); ++i)
{
auto const& memberName = structMembers.at(i)->name();
auto newMember = memberName == _member ? _memberValue : oldMembers.at(i);
m_context.addAssertion(member(memberName) == newMember);
}
return currentValue();
}
smtutil::Expression SymbolicStructVariable::assignAllMembers(std::vector<smtutil::Expression> const& _memberValues)
{
auto structType = dynamic_cast<StructType const*>(m_type);
solAssert(structType, "");
auto const& structDef = structType->structDefinition();
auto const& structMembers = structDef.members();
solAssert(_memberValues.size() == structMembers.size(), "");
increaseIndex();
for (unsigned i = 0; i < _memberValues.size(); ++i)
m_context.addAssertion(_memberValues[i] == member(structMembers[i]->name()));
return currentValue();
}