[SMTChecker] Supporting conditional operator

libsolidity/formal/BMC.cpp

@@ -198,6 +198,24 @@ bool BMC::visit(IfStatement const& _node)
 	return false;
 }
 
+bool BMC::visit(Conditional const& _op)
+{
+	m_context.pushSolver();
+	_op.condition().accept(*this);
+
+	if (isRootFunction())
+		addVerificationTarget(
+			VerificationTarget::Type::ConstantCondition,
+			expr(_op.condition()),
+			&_op.condition()
+		);
+	m_context.popSolver();
+
+	SMTEncoder::visit(_op);
+
+	return false;
+}
+
 // Here we consider the execution of two branches:
 // Branch 1 assumes the loop condition to be true and executes the loop once,
 // after resetting touched variables.

libsolidity/formal/BMC.h

@@ -84,6 +84,7 @@ private:
 	bool visit(FunctionDefinition const& _node) override;
 	void endVisit(FunctionDefinition const& _node) override;
 	bool visit(IfStatement const& _node) override;
+	bool visit(Conditional const& _node) override;
 	bool visit(WhileStatement const& _node) override;
 	bool visit(ForStatement const& _node) override;
 	void endVisit(UnaryOperation const& _node) override;

libsolidity/formal/SMTEncoder.cpp

@@ -579,6 +579,27 @@ void SMTEncoder::endVisit(BinaryOperation const& _op)
 		);
 }
 
+bool SMTEncoder::visit(Conditional const& _op)
+{
+	_op.condition().accept(*this);
+
+	auto indicesEndTrue = visitBranch(&_op.trueExpression(), expr(_op.condition()));
+	auto touchedVars = touchedVariables(_op.trueExpression());
+
+	auto indicesEndFalse = visitBranch(&_op.falseExpression(), !expr(_op.condition()));
+	touchedVars += touchedVariables(_op.falseExpression());
+
+	mergeVariables(touchedVars, expr(_op.condition()), indicesEndTrue, indicesEndFalse);
+
+	defineExpr(_op, smtutil::Expression::ite(
+		expr(_op.condition()),
+		expr(_op.trueExpression()),
+		expr(_op.falseExpression())
+	));
+
+	return false;
+}
+
 void SMTEncoder::endVisit(FunctionCall const& _funCall)
 {
 	auto functionCallKind = *_funCall.annotation().kind;

libsolidity/formal/SMTEncoder.h

@@ -83,6 +83,7 @@ protected:
 	void endVisit(UnaryOperation const& _node) override;
 	bool visit(BinaryOperation const& _node) override;
 	void endVisit(BinaryOperation const& _node) override;
+	bool visit(Conditional const& _node) override;
 	void endVisit(FunctionCall const& _node) override;
 	bool visit(ModifierInvocation const& _node) override;
 	void endVisit(Identifier const& _node) override;