Merge pull request #3406 from leonardoalt/smt_checker

SMTChecker: A little refactoring on SSA vars (preparation for Bool)

1 files changed, 56 insertions, 0 deletions

diff --git a/libsolidity/formal/SymbolicIntVariable.cpp b/libsolidity/formal/SymbolicIntVariable.cpp
new file mode 100644
index 00000000..d08dc155
--- /dev/null
+++ b/libsolidity/formal/SymbolicIntVariable.cpp
@@ -0,0 +1,56 @@
+/*
+	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/>.
+*/
+
+#include <libsolidity/formal/SymbolicIntVariable.h>
+
+#include <libsolidity/ast/AST.h>
+
+using namespace std;
+using namespace dev;
+using namespace dev::solidity;
+
+SymbolicIntVariable::SymbolicIntVariable(
+	Declaration const* _decl,
+	smt::SolverInterface& _interface
+):
+	SymbolicVariable(_decl, _interface)
+{
+	solAssert(m_declaration->type()->category() == Type::Category::Integer, "");
+	m_expression = make_shared<smt::Expression>(m_interface.newFunction(uniqueSymbol(), smt::Sort::Int, smt::Sort::Int));
+}
+
+void SymbolicIntVariable::setZeroValue(int _seq)
+{
+	m_interface.addAssertion(valueAtSequence(_seq) == 0);
+}
+
+void SymbolicIntVariable::setUnknownValue(int _seq)
+{
+	auto const& intType = dynamic_cast<IntegerType const&>(*m_declaration->type());
+	m_interface.addAssertion(valueAtSequence(_seq) >= minValue(intType));
+	m_interface.addAssertion(valueAtSequence(_seq) <= maxValue(intType));
+}
+
+smt::Expression SymbolicIntVariable::minValue(IntegerType const& _t)
+{
+	return smt::Expression(_t.minValue());
+}
+
+smt::Expression SymbolicIntVariable::maxValue(IntegerType const& _t)
+{
+	return smt::Expression(_t.maxValue());
+}