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authorchriseth <chris@ethereum.org>2017-07-14 00:22:51 +0800
committerchriseth <chris@ethereum.org>2017-08-23 23:37:35 +0800
commit4cea3d4aa44194e052520fea2f6d216675d3bd14 (patch)
tree5c61271a42c2068a4387bdc2eefee3c27f04fe85 /libsolidity
parentc9cf24458baa77e2a2de1bedbad5040d0d83aab2 (diff)
downloaddexon-solidity-4cea3d4aa44194e052520fea2f6d216675d3bd14.tar.gz
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Insert abstraction layer.
Diffstat (limited to 'libsolidity')
-rw-r--r--libsolidity/formal/SMTChecker.cpp53
-rw-r--r--libsolidity/formal/SMTChecker.h4
-rw-r--r--libsolidity/formal/SMTLib2Interface.cpp21
-rw-r--r--libsolidity/formal/SMTLib2Interface.h127
-rw-r--r--libsolidity/formal/SolverInterface.h168
5 files changed, 225 insertions, 148 deletions
diff --git a/libsolidity/formal/SMTChecker.cpp b/libsolidity/formal/SMTChecker.cpp
index 76232c2e..a8ad60ed 100644
--- a/libsolidity/formal/SMTChecker.cpp
+++ b/libsolidity/formal/SMTChecker.cpp
@@ -17,6 +17,7 @@
#include <libsolidity/formal/SMTChecker.h>
+#include <libsolidity/formal/SMTLib2Interface.h>
#include <libsolidity/interface/ErrorReporter.h>
@@ -25,7 +26,7 @@ using namespace dev;
using namespace dev::solidity;
SMTChecker::SMTChecker(ErrorReporter& _errorReporter, ReadFile::Callback const& _readFileCallback):
- m_interface(_readFileCallback),
+ m_interface(make_shared<smt::SMTLib2Interface>(_readFileCallback)),
m_errorReporter(_errorReporter)
{
}
@@ -39,7 +40,7 @@ void SMTChecker::analyze(SourceUnit const& _source)
pragmaFound = true;
if (pragmaFound)
{
- m_interface.reset();
+ m_interface->reset();
m_currentSequenceCounter.clear();
_source.accept(*this);
}
@@ -69,7 +70,7 @@ bool SMTChecker::visit(FunctionDefinition const& _function)
);
// TODO actually we probably also have to reset all local variables and similar things.
m_currentFunction = &_function;
- m_interface.push();
+ m_interface->push();
return true;
}
@@ -79,7 +80,7 @@ void SMTChecker::endVisit(FunctionDefinition const&)
// We only handle local variables, so we clear everything.
// If we add storage variables, those should be cleared differently.
m_currentSequenceCounter.clear();
- m_interface.pop();
+ m_interface->pop();
m_currentFunction = nullptr;
}
@@ -93,7 +94,7 @@ void SMTChecker::endVisit(VariableDeclarationStatement const& _varDecl)
else if (knownVariable(*_varDecl.declarations()[0]) && _varDecl.initialValue())
// TODO more checks?
// TODO add restrictions about type (might be assignment from smaller type)
- m_interface.addAssertion(newValue(*_varDecl.declarations()[0]) == expr(*_varDecl.initialValue()));
+ m_interface->addAssertion(newValue(*_varDecl.declarations()[0]) == expr(*_varDecl.initialValue()));
else
m_errorReporter.warning(
_varDecl.location(),
@@ -123,7 +124,7 @@ void SMTChecker::endVisit(Assignment const& _assignment)
if (knownVariable(*decl))
// TODO more checks?
// TODO add restrictions about type (might be assignment from smaller type)
- m_interface.addAssertion(newValue(*decl) == expr(_assignment.rightHandSide()));
+ m_interface->addAssertion(newValue(*decl) == expr(_assignment.rightHandSide()));
else
m_errorReporter.warning(
_assignment.location(),
@@ -145,7 +146,7 @@ void SMTChecker::endVisit(TupleExpression const& _tuple)
"Assertion checker does not yet implement tules and inline arrays."
);
else
- m_interface.addAssertion(expr(_tuple) == expr(*_tuple.components()[0]));
+ m_interface->addAssertion(expr(_tuple) == expr(*_tuple.components()[0]));
}
void SMTChecker::endVisit(BinaryOperation const& _op)
@@ -173,13 +174,13 @@ void SMTChecker::endVisit(FunctionCall const& _funCall)
solAssert(args.size() == 1, "");
solAssert(args[0]->annotation().type->category() == Type::Category::Bool, "");
checkCondition(!(expr(*args[0])), _funCall.location(), "Assertion violation");
- m_interface.addAssertion(expr(*args[0]));
+ m_interface->addAssertion(expr(*args[0]));
}
else if (funType.kind() == FunctionType::Kind::Require)
{
solAssert(args.size() == 1, "");
solAssert(args[0]->annotation().type->category() == Type::Category::Bool, "");
- m_interface.addAssertion(expr(*args[0]));
+ m_interface->addAssertion(expr(*args[0]));
checkCondition(!(expr(*args[0])), _funCall.location(), "Unreachable code");
// TODO is there something meaningful we can check here?
// We can check whether the condition is always fulfilled or never fulfilled.
@@ -192,7 +193,7 @@ void SMTChecker::endVisit(Identifier const& _identifier)
solAssert(decl, "");
if (dynamic_cast<IntegerType const*>(_identifier.annotation().type.get()))
{
- m_interface.addAssertion(expr(_identifier) == currentValue(*decl));
+ m_interface->addAssertion(expr(_identifier) == currentValue(*decl));
return;
}
else if (FunctionType const* fun = dynamic_cast<FunctionType const*>(_identifier.annotation().type.get()))
@@ -217,7 +218,7 @@ void SMTChecker::endVisit(Literal const& _literal)
if (RationalNumberType const* rational = dynamic_cast<RationalNumberType const*>(&type))
solAssert(!rational->isFractional(), "");
- m_interface.addAssertion(expr(_literal) == smt::Expression(type.literalValue(&_literal)));
+ m_interface->addAssertion(expr(_literal) == smt::Expression(type.literalValue(&_literal)));
}
else
m_errorReporter.warning(
@@ -264,7 +265,7 @@ void SMTChecker::arithmeticOperation(BinaryOperation const& _op)
&value
);
- m_interface.addAssertion(expr(_op) == value);
+ m_interface->addAssertion(expr(_op) == value);
break;
}
default:
@@ -292,7 +293,7 @@ void SMTChecker::compareOperation(BinaryOperation const& _op)
/*op == Token::GreaterThanOrEqual*/ (left >= right)
);
// TODO: check that other values for op are not possible.
- m_interface.addAssertion(expr(_op) == value);
+ m_interface->addAssertion(expr(_op) == value);
}
else
m_errorReporter.warning(
@@ -308,9 +309,9 @@ void SMTChecker::booleanOperation(BinaryOperation const& _op)
if (_op.annotation().commonType->category() == Type::Category::Bool)
{
if (_op.getOperator() == Token::And)
- m_interface.addAssertion(expr(_op) == expr(_op.leftExpression()) && expr(_op.rightExpression()));
+ m_interface->addAssertion(expr(_op) == expr(_op.leftExpression()) && expr(_op.rightExpression()));
else
- m_interface.addAssertion(expr(_op) == expr(_op.leftExpression()) || expr(_op.rightExpression()));
+ m_interface->addAssertion(expr(_op) == expr(_op.leftExpression()) || expr(_op.rightExpression()));
}
else
m_errorReporter.warning(
@@ -327,8 +328,8 @@ void SMTChecker::checkCondition(
smt::Expression* _additionalValue
)
{
- m_interface.push();
- m_interface.addAssertion(_condition);
+ m_interface->push();
+ m_interface->addAssertion(_condition);
vector<smt::Expression> expressionsToEvaluate;
if (m_currentFunction)
@@ -344,7 +345,7 @@ void SMTChecker::checkCondition(
}
smt::CheckResult result;
vector<string> values;
- tie(result, values) = m_interface.check(expressionsToEvaluate);
+ tie(result, values) = m_interface->check(expressionsToEvaluate);
switch (result)
{
case smt::CheckResult::SAT:
@@ -380,7 +381,7 @@ void SMTChecker::checkCondition(
default:
solAssert(false, "");
}
- m_interface.pop();
+ m_interface->pop();
}
void SMTChecker::createVariable(VariableDeclaration const& _varDecl, bool _setToZero)
@@ -390,13 +391,13 @@ void SMTChecker::createVariable(VariableDeclaration const& _varDecl, bool _setTo
solAssert(m_currentSequenceCounter.count(&_varDecl) == 0, "");
solAssert(m_z3Variables.count(&_varDecl) == 0, "");
m_currentSequenceCounter[&_varDecl] = 0;
- m_z3Variables.emplace(&_varDecl, m_interface.newFunction(uniqueSymbol(_varDecl), smt::Sort::Int, smt::Sort::Int));
+ m_z3Variables.emplace(&_varDecl, m_interface->newFunction(uniqueSymbol(_varDecl), smt::Sort::Int, smt::Sort::Int));
if (_setToZero)
- m_interface.addAssertion(currentValue(_varDecl) == 0);
+ m_interface->addAssertion(currentValue(_varDecl) == 0);
else
{
- m_interface.addAssertion(currentValue(_varDecl) >= minValue(*intType));
- m_interface.addAssertion(currentValue(_varDecl) <= maxValue(*intType));
+ m_interface->addAssertion(currentValue(_varDecl) >= minValue(*intType));
+ m_interface->addAssertion(currentValue(_varDecl) <= maxValue(*intType));
}
}
else
@@ -455,14 +456,14 @@ smt::Expression SMTChecker::expr(Expression const& _e)
{
if (RationalNumberType const* rational = dynamic_cast<RationalNumberType const*>(_e.annotation().type.get()))
solAssert(!rational->isFractional(), "");
- m_z3Expressions.emplace(&_e, m_interface.newInteger(uniqueSymbol(_e)));
+ m_z3Expressions.emplace(&_e, m_interface->newInteger(uniqueSymbol(_e)));
break;
}
case Type::Category::Integer:
- m_z3Expressions.emplace(&_e, m_interface.newInteger(uniqueSymbol(_e)));
+ m_z3Expressions.emplace(&_e, m_interface->newInteger(uniqueSymbol(_e)));
break;
case Type::Category::Bool:
- m_z3Expressions.emplace(&_e, m_interface.newBool(uniqueSymbol(_e)));
+ m_z3Expressions.emplace(&_e, m_interface->newBool(uniqueSymbol(_e)));
break;
default:
solAssert(false, "Type not implemented.");
diff --git a/libsolidity/formal/SMTChecker.h b/libsolidity/formal/SMTChecker.h
index 8c6a2327..afe5897d 100644
--- a/libsolidity/formal/SMTChecker.h
+++ b/libsolidity/formal/SMTChecker.h
@@ -18,7 +18,7 @@
#pragma once
#include <libsolidity/ast/ASTVisitor.h>
-#include <libsolidity/formal/SMTLib2Interface.h>
+#include <libsolidity/formal/SolverInterface.h>
#include <libsolidity/interface/ReadFile.h>
#include <map>
@@ -85,7 +85,7 @@ private:
/// The function takes one argument which is the "sequence number".
smt::Expression var(Declaration const& _decl);
- smt::SMTLib2Interface m_interface;
+ std::shared_ptr<smt::SolverInterface> m_interface;
std::map<Declaration const*, int> m_currentSequenceCounter;
std::map<Expression const*, smt::Expression> m_z3Expressions;
std::map<Declaration const*, smt::Expression> m_z3Variables;
diff --git a/libsolidity/formal/SMTLib2Interface.cpp b/libsolidity/formal/SMTLib2Interface.cpp
index 63ab1679..8cc4da66 100644
--- a/libsolidity/formal/SMTLib2Interface.cpp
+++ b/libsolidity/formal/SMTLib2Interface.cpp
@@ -71,24 +71,24 @@ Expression SMTLib2Interface::newFunction(string _name, Sort _domain, Sort _codom
(_codomain == Sort::Int ? "Int" : "Bool") +
")"
);
- return Expression(std::move(_name), {});
+ return SolverInterface::newFunction(move(_name), _domain, _codomain);
}
Expression SMTLib2Interface::newInteger(string _name)
{
write("(declare-const |" + _name + "| Int)");
- return Expression(std::move(_name), {});
+ return SolverInterface::newInteger(move(_name));
}
Expression SMTLib2Interface::newBool(string _name)
{
write("(declare-const |" + _name + "| Bool)");
- return Expression(std::move(_name), {});
+ return SolverInterface::newBool(std::move(_name));
}
void SMTLib2Interface::addAssertion(Expression const& _expr)
{
- write("(assert " + _expr.toSExpr() + ")");
+ write("(assert " + toSExpr(_expr) + ")");
}
pair<CheckResult, vector<string>> SMTLib2Interface::check(vector<Expression> const& _expressionsToEvaluate)
@@ -114,6 +114,17 @@ pair<CheckResult, vector<string>> SMTLib2Interface::check(vector<Expression> con
return make_pair(result, values);
}
+string SMTLib2Interface::toSExpr(Expression const& _expr)
+{
+ if (_expr.arguments.empty())
+ return _expr.name;
+ std::string sexpr = "(" + _expr.name;
+ for (auto const& arg: _expr.arguments)
+ sexpr += " " + toSExpr(arg);
+ sexpr += ")";
+ return sexpr;
+}
+
void SMTLib2Interface::write(string _data)
{
solAssert(!m_accumulatedOutput.empty(), "");
@@ -133,7 +144,7 @@ string SMTLib2Interface::checkSatAndGetValuesCommand(vector<Expression> const& _
auto const& e = _expressionsToEvaluate.at(i);
// TODO they don't have to be ints...
command += "(declare-const |EVALEXPR_" + to_string(i) + "| Int)\n";
- command += "(assert (= |EVALEXPR_" + to_string(i) + "| " + e.toSExpr() + "))\n";
+ command += "(assert (= |EVALEXPR_" + to_string(i) + "| " + toSExpr(e) + "))\n";
}
command += "(check-sat)\n";
command += "(get-value (";
diff --git a/libsolidity/formal/SMTLib2Interface.h b/libsolidity/formal/SMTLib2Interface.h
index d8c11df9..5755ae3f 100644
--- a/libsolidity/formal/SMTLib2Interface.h
+++ b/libsolidity/formal/SMTLib2Interface.h
@@ -18,6 +18,7 @@
#pragma once
#include <libsolidity/formal/SMTSolverCommunicator.h>
+#include <libsolidity/formal/SolverInterface.h>
#include <libsolidity/interface/Exceptions.h>
#include <libsolidity/interface/ReadFile.h>
@@ -38,129 +39,26 @@ namespace solidity
namespace smt
{
-enum class CheckResult
-{
- SAT, UNSAT, UNKNOWN, ERROR
-};
-
-enum class Sort
-{
- Int, Bool
-};
-
-/// C++ representation of an SMTLIB2 expression.
-class Expression
-{
- friend class SMTLib2Interface;
- /// Manual constructor, should only be used by SMTLib2Interface and the class itself.
- Expression(std::string _name, std::vector<Expression> _arguments):
- m_name(std::move(_name)), m_arguments(std::move(_arguments)) {}
-
-public:
- Expression(size_t _number): m_name(std::to_string(_number)) {}
- Expression(u256 const& _number): m_name(_number.str()) {}
- Expression(bigint const& _number): m_name(_number.str()) {}
-
- Expression(Expression const& _other) = default;
- Expression(Expression&& _other) = default;
- Expression& operator=(Expression const& _other) = default;
- Expression& operator=(Expression&& _other) = default;
-
- friend Expression operator!(Expression _a)
- {
- return Expression("not", std::move(_a));
- }
- friend Expression operator&&(Expression _a, Expression _b)
- {
- return Expression("and", std::move(_a), std::move(_b));
- }
- friend Expression operator||(Expression _a, Expression _b)
- {
- return Expression("or", std::move(_a), std::move(_b));
- }
- friend Expression operator==(Expression _a, Expression _b)
- {
- return Expression("=", std::move(_a), std::move(_b));
- }
- 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));
- }
- friend Expression operator<=(Expression _a, Expression _b)
- {
- return Expression("<=", std::move(_a), std::move(_b));
- }
- friend Expression operator>(Expression _a, Expression _b)
- {
- return Expression(">", std::move(_a), std::move(_b));
- }
- friend Expression operator>=(Expression _a, Expression _b)
- {
- return Expression(">=", std::move(_a), std::move(_b));
- }
- friend Expression operator+(Expression _a, Expression _b)
- {
- return Expression("+", std::move(_a), std::move(_b));
- }
- friend Expression operator-(Expression _a, Expression _b)
- {
- return Expression("-", std::move(_a), std::move(_b));
- }
- friend Expression operator*(Expression _a, Expression _b)
- {
- return Expression("*", std::move(_a), std::move(_b));
- }
- Expression operator()(Expression _a) const
- {
- solAssert(m_arguments.empty(), "Attempted function application to non-function.");
- return Expression(m_name, _a);
- }
-
- std::string toSExpr() const
- {
- if (m_arguments.empty())
- return m_name;
- std::string sexpr = "(" + m_name;
- for (auto const& arg: m_arguments)
- sexpr += " " + arg.toSExpr();
- sexpr += ")";
- return sexpr;
- }
-
-private:
- explicit Expression(std::string _name):
- Expression(std::move(_name), std::vector<Expression>{}) {}
- Expression(std::string _name, Expression _arg):
- Expression(std::move(_name), std::vector<Expression>{std::move(_arg)}) {}
- Expression(std::string _name, Expression _arg1, Expression _arg2):
- Expression(std::move(_name), std::vector<Expression>{std::move(_arg1), std::move(_arg2)}) {}
-
- std::string const m_name;
- std::vector<Expression> const m_arguments;
-};
-
-class SMTLib2Interface: public boost::noncopyable
+class SMTLib2Interface: public SolverInterface, public boost::noncopyable
{
public:
SMTLib2Interface(ReadFile::Callback const& _readFileCallback);
- void reset();
+ void reset() override;
- void push();
- void pop();
+ void push() override;
+ void pop() override;
- Expression newFunction(std::string _name, Sort _domain, Sort _codomain);
- Expression newInteger(std::string _name);
- Expression newBool(std::string _name);
+ Expression newFunction(std::string _name, Sort _domain, Sort _codomain) override;
+ Expression newInteger(std::string _name) override;
+ Expression newBool(std::string _name) override;
- void addAssertion(Expression const& _expr);
- std::pair<CheckResult, std::vector<std::string>> check(std::vector<Expression> const& _expressionsToEvaluate);
+ void addAssertion(Expression const& _expr) override;
+ std::pair<CheckResult, std::vector<std::string>> check(std::vector<Expression> const& _expressionsToEvaluate) override;
private:
+ std::string toSExpr(Expression const& _expr);
+
void write(std::string _data);
std::string checkSatAndGetValuesCommand(std::vector<Expression> const& _expressionsToEvaluate);
@@ -170,7 +68,6 @@ private:
std::vector<std::string> m_accumulatedOutput;
};
-
}
}
}
diff --git a/libsolidity/formal/SolverInterface.h b/libsolidity/formal/SolverInterface.h
new file mode 100644
index 00000000..e9fa5cc7
--- /dev/null
+++ b/libsolidity/formal/SolverInterface.h
@@ -0,0 +1,168 @@
+/*
+ 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/formal/SMTSolverCommunicator.h>
+
+#include <libsolidity/interface/Exceptions.h>
+#include <libsolidity/interface/ReadFile.h>
+
+#include <libdevcore/Common.h>
+
+#include <boost/noncopyable.hpp>
+
+#include <map>
+#include <string>
+#include <vector>
+#include <cstdio>
+
+namespace dev
+{
+namespace solidity
+{
+namespace smt
+{
+
+enum class CheckResult
+{
+ SAT, UNSAT, UNKNOWN, ERROR
+};
+
+enum class Sort
+{
+ Int, Bool
+};
+
+/// C++ representation of an SMTLIB2 expression.
+class Expression
+{
+ friend class SolverInterface;
+public:
+ Expression(size_t _number): name(std::to_string(_number)) {}
+ Expression(u256 const& _number): name(_number.str()) {}
+ Expression(bigint const& _number): name(_number.str()) {}
+
+ Expression(Expression const& _other) = default;
+ Expression(Expression&& _other) = default;
+ Expression& operator=(Expression const& _other) = default;
+ Expression& operator=(Expression&& _other) = default;
+
+ friend Expression operator!(Expression _a)
+ {
+ return Expression("not", std::move(_a));
+ }
+ friend Expression operator&&(Expression _a, Expression _b)
+ {
+ return Expression("and", std::move(_a), std::move(_b));
+ }
+ friend Expression operator||(Expression _a, Expression _b)
+ {
+ return Expression("or", std::move(_a), std::move(_b));
+ }
+ friend Expression operator==(Expression _a, Expression _b)
+ {
+ return Expression("=", std::move(_a), std::move(_b));
+ }
+ 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));
+ }
+ friend Expression operator<=(Expression _a, Expression _b)
+ {
+ return Expression("<=", std::move(_a), std::move(_b));
+ }
+ friend Expression operator>(Expression _a, Expression _b)
+ {
+ return Expression(">", std::move(_a), std::move(_b));
+ }
+ friend Expression operator>=(Expression _a, Expression _b)
+ {
+ return Expression(">=", std::move(_a), std::move(_b));
+ }
+ friend Expression operator+(Expression _a, Expression _b)
+ {
+ return Expression("+", std::move(_a), std::move(_b));
+ }
+ friend Expression operator-(Expression _a, Expression _b)
+ {
+ return Expression("-", std::move(_a), std::move(_b));
+ }
+ friend Expression operator*(Expression _a, Expression _b)
+ {
+ return Expression("*", std::move(_a), std::move(_b));
+ }
+ Expression operator()(Expression _a) const
+ {
+ solAssert(arguments.empty(), "Attempted function application to non-function.");
+ return Expression(name, _a);
+ }
+
+ std::string const name;
+ std::vector<Expression> const arguments;
+
+private:
+ /// Manual constructor, should only be used by SolverInterface and this class itself.
+ Expression(std::string _name, std::vector<Expression> _arguments):
+ name(std::move(_name)), arguments(std::move(_arguments)) {}
+
+ explicit Expression(std::string _name):
+ Expression(std::move(_name), std::vector<Expression>{}) {}
+ Expression(std::string _name, Expression _arg):
+ Expression(std::move(_name), std::vector<Expression>{std::move(_arg)}) {}
+ Expression(std::string _name, Expression _arg1, Expression _arg2):
+ Expression(std::move(_name), std::vector<Expression>{std::move(_arg1), std::move(_arg2)}) {}
+};
+
+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*/)
+ {
+ // Subclasses should do something here
+ return Expression(std::move(_name), {});
+ }
+ virtual Expression newInteger(std::string _name)
+ {
+ // Subclasses should do something here
+ return Expression(std::move(_name), {});
+ }
+ virtual Expression newBool(std::string _name)
+ {
+ // Subclasses should do something here
+ return Expression(std::move(_name), {});
+ }
+
+ virtual void addAssertion(Expression const& _expr) = 0;
+
+ virtual std::pair<CheckResult, std::vector<std::string>>
+ check(std::vector<Expression> const& _expressionsToEvaluate) = 0;
+};
+
+
+}
+}
+}