solidity/libsolidity/formal/SolverInterface.h

219 lines
6.2 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/>.
*/
#pragma once
#include <libsolidity/interface/Exceptions.h>
#include <libsolidity/interface/ReadFile.h>
#include <libdevcore/Common.h>
#include <libdevcore/Exceptions.h>
#include <boost/noncopyable.hpp>
#include <map>
#include <string>
#include <vector>
#include <cstdio>
namespace dev
{
namespace solidity
{
namespace smt
{
enum class CheckResult
{
SATISFIABLE, UNSATISFIABLE, UNKNOWN, ERROR
};
enum class Sort
{
Int,
Bool,
IntIntFun, // Function of one Int returning a single Int
IntBoolFun // Function of one Int returning a single Bool
};
/// C++ representation of an SMTLIB2 expression.
class Expression
{
friend class SolverInterface;
public:
explicit Expression(bool _v): name(_v ? "true" : "false"), sort(Sort::Bool) {}
Expression(size_t _number): name(std::to_string(_number)), sort(Sort::Int) {}
Expression(u256 const& _number): name(_number.str()), sort(Sort::Int) {}
Expression(bigint const& _number): name(_number.str()), sort(Sort::Int) {}
Expression(Expression const&) = default;
Expression(Expression&&) = default;
Expression& operator=(Expression const&) = default;
Expression& operator=(Expression&&) = default;
static Expression ite(Expression _condition, Expression _trueValue, Expression _falseValue)
{
solAssert(_trueValue.sort == _falseValue.sort, "");
return Expression("ite", std::vector<Expression>{
std::move(_condition), std::move(_trueValue), std::move(_falseValue)
}, _trueValue.sort);
}
static Expression implies(Expression _a, Expression _b)
{
return !std::move(_a) || std::move(_b);
}
friend Expression operator!(Expression _a)
{
return Expression("not", std::move(_a), Sort::Bool);
}
friend Expression operator&&(Expression _a, Expression _b)
{
return Expression("and", std::move(_a), std::move(_b), Sort::Bool);
}
friend Expression operator||(Expression _a, Expression _b)
{
return Expression("or", std::move(_a), std::move(_b), Sort::Bool);
}
friend Expression operator==(Expression _a, Expression _b)
{
return Expression("=", std::move(_a), std::move(_b), Sort::Bool);
}
friend Expression operator!=(Expression _a, Expression _b)
{
return !(std::move(_a) == std::move(_b));
}
friend Expression operator<(Expression _a, Expression _b)
{
return Expression("<", std::move(_a), std::move(_b), Sort::Bool);
}
friend Expression operator<=(Expression _a, Expression _b)
{
return Expression("<=", std::move(_a), std::move(_b), Sort::Bool);
}
friend Expression operator>(Expression _a, Expression _b)
{
return Expression(">", std::move(_a), std::move(_b), Sort::Bool);
}
friend Expression operator>=(Expression _a, Expression _b)
{
return Expression(">=", std::move(_a), std::move(_b), Sort::Bool);
}
friend Expression operator+(Expression _a, Expression _b)
{
return Expression("+", std::move(_a), std::move(_b), Sort::Int);
}
friend Expression operator-(Expression _a, Expression _b)
{
return Expression("-", std::move(_a), std::move(_b), Sort::Int);
}
friend Expression operator*(Expression _a, Expression _b)
{
return Expression("*", std::move(_a), std::move(_b), Sort::Int);
}
friend Expression operator/(Expression _a, Expression _b)
{
return Expression("/", std::move(_a), std::move(_b), Sort::Int);
}
Expression operator()(Expression _a) const
{
solAssert(
arguments.empty(),
"Attempted function application to non-function."
);
switch (sort)
{
case Sort::IntIntFun:
return Expression(name, _a, Sort::Int);
case Sort::IntBoolFun:
return Expression(name, _a, Sort::Bool);
default:
solAssert(
false,
"Attempted function application to invalid type."
);
break;
}
}
std::string const name;
std::vector<Expression> const arguments;
Sort sort;
private:
/// Manual constructor, should only be used by SolverInterface and this class itself.
Expression(std::string _name, std::vector<Expression> _arguments, Sort _sort):
name(std::move(_name)), arguments(std::move(_arguments)), sort(_sort) {}
explicit Expression(std::string _name, Sort _sort):
Expression(std::move(_name), std::vector<Expression>{}, _sort) {}
Expression(std::string _name, Expression _arg, Sort _sort):
Expression(std::move(_name), std::vector<Expression>{std::move(_arg)}, _sort) {}
Expression(std::string _name, Expression _arg1, Expression _arg2, Sort _sort):
Expression(std::move(_name), std::vector<Expression>{std::move(_arg1), std::move(_arg2)}, _sort) {}
};
DEV_SIMPLE_EXCEPTION(SolverError);
class SolverInterface
{
public:
virtual void reset() = 0;
virtual void push() = 0;
virtual void pop() = 0;
virtual Expression newFunction(std::string _name, Sort _domain, Sort _codomain)
{
solAssert(_domain == Sort::Int, "Function sort not supported.");
// Subclasses should do something here
switch (_codomain)
{
case Sort::Int:
return Expression(std::move(_name), {}, Sort::IntIntFun);
case Sort::Bool:
return Expression(std::move(_name), {}, Sort::IntBoolFun);
default:
solAssert(false, "Function sort not supported.");
break;
}
}
virtual Expression newInteger(std::string _name)
{
// Subclasses should do something here
return Expression(std::move(_name), {}, Sort::Int);
}
virtual Expression newBool(std::string _name)
{
// Subclasses should do something here
return Expression(std::move(_name), {}, Sort::Bool);
}
virtual void addAssertion(Expression const& _expr) = 0;
/// Checks for satisfiability, evaluates the expressions if a model
/// is available. Throws SMTSolverError on error.
virtual std::pair<CheckResult, std::vector<std::string>>
check(std::vector<Expression> const& _expressionsToEvaluate) = 0;
};
}
}
}