fixed issues in division operations of sylvan for rational numbers and rational functions (division by zero not correctly handled)

resources/3rdparty/sylvan/src/storm_wrapper.cpp

@@ -109,6 +109,15 @@ storm_rational_number_ptr storm_rational_number_get_one() {
     return (storm_rational_number_ptr)result_srn;
 }
 
+storm_rational_number_ptr storm_rational_number_get_infinity() {
+#ifndef RATIONAL_NUMBER_THREAD_SAFE
+    std::lock_guard<std::mutex> lock(rationalNumberMutex);
+#endif
+    
+    storm::RationalNumber* result_srn = new storm::RationalNumber(storm::utility::infinity<storm::RationalNumber>());
+    return (storm_rational_number_ptr)result_srn;
+}
+
 int storm_rational_number_is_zero(storm_rational_number_ptr a) {
 #ifndef RATIONAL_NUMBER_THREAD_SAFE
     std::lock_guard<std::mutex> lock(rationalNumberMutex);
@@ -404,6 +413,16 @@ storm_rational_function_ptr storm_rational_function_get_one() {
     return (storm_rational_function_ptr)result_srf;
 }
 
+storm_rational_function_ptr storm_rational_function_get_infinity() {
+#ifndef RATIONAL_FUNCTION_THREAD_SAFE
+    std::lock_guard<std::mutex> lock(rationalFunctionMutex);
+#endif
+    
+    storm::RationalFunction* result_srf = new storm::RationalFunction(storm::utility::infinity<storm::RationalFunction>());
+    return (storm_rational_function_ptr)result_srf;
+}
+
+
 int storm_rational_function_is_zero(storm_rational_function_ptr a) {
 #ifndef RATIONAL_FUNCTION_THREAD_SAFE
     std::lock_guard<std::mutex> lock(rationalFunctionMutex);

resources/3rdparty/sylvan/src/storm_wrapper.h

@@ -25,6 +25,7 @@ extern "C" {
     storm_rational_number_ptr storm_rational_number_clone(storm_rational_number_ptr a);
     storm_rational_number_ptr storm_rational_number_get_zero();
     storm_rational_number_ptr storm_rational_number_get_one();
+    storm_rational_number_ptr storm_rational_number_get_infinity();
     int storm_rational_number_is_zero(storm_rational_number_ptr a);
     uint64_t storm_rational_number_hash(storm_rational_number_ptr const a, uint64_t const seed);
     double storm_rational_number_get_value_double(storm_rational_number_ptr a);
@@ -71,6 +72,7 @@ extern "C" {
     storm_rational_function_ptr storm_rational_function_clone(storm_rational_function_ptr a);
     storm_rational_function_ptr storm_rational_function_get_zero();
     storm_rational_function_ptr storm_rational_function_get_one();
+    storm_rational_number_ptr storm_rational_function_get_infinity();
     int storm_rational_function_is_zero(storm_rational_function_ptr a);
     uint64_t storm_rational_function_hash(storm_rational_function_ptr const a, uint64_t const seed);
     double storm_rational_function_get_value_double(storm_rational_function_ptr a);

resources/3rdparty/sylvan/src/sylvan_mtbdd_storm.c

@@ -43,10 +43,16 @@ TASK_IMPL_2(MTBDD, mtbdd_op_divide, MTBDD*, pa, MTBDD*, pb)
             double vval_a = *(double*)&val_a;
             double vval_b = *(double*)&val_b;
             if (vval_a == 0.0) return a;
-            else if (vval_b == 0.0) return b;
-            else {
+            else if (vval_b == 0.0) {
+                if (vval_a > 0.0) {
+                    return mtbdd_double(INFINITY);
+                } else {
+                    return mtbdd_double(-INFINITY);
+                }
+                return b;
+            } else {
                 MTBDD result;
-                if (vval_a == 0.0 || vval_b == 1.0) result = a;
+                if (vval_b == 1.0) result = a;
                 result = mtbdd_double(vval_a / vval_b);
                 return result;
             }

resources/3rdparty/sylvan/src/sylvan_storm_rational_function.c

@@ -194,9 +194,12 @@ TASK_IMPL_2(MTBDD, sylvan_storm_rational_function_op_divide, MTBDD*, pa, MTBDD*,
     /* If both leaves, compute division */
     if (mtbdd_isleaf(a) && mtbdd_isleaf(b)) {
 		storm_rational_function_ptr ma = mtbdd_getstorm_rational_function_ptr(a);
+        storm_rational_function_ptr mb = mtbdd_getstorm_rational_function_ptr(b);
         storm_rational_function_ptr mres;
         if (storm_rational_function_is_zero(ma)) {
             mres = storm_rational_function_get_zero();
+        } else if (storm_rational_function_is_zero(mb)) {
+            mres = storm_rational_function_get_infinity();
         } else {
             storm_rational_function_ptr mb = mtbdd_getstorm_rational_function_ptr(b);
             mres = storm_rational_function_divide(ma, mb);

resources/3rdparty/sylvan/src/sylvan_storm_rational_number.c

@@ -194,9 +194,12 @@ TASK_IMPL_2(MTBDD, sylvan_storm_rational_number_op_divide, MTBDD*, pa, MTBDD*, p
     /* If both leaves, compute division */
     if (mtbdd_isleaf(a) && mtbdd_isleaf(b)) {
 		storm_rational_number_ptr ma = mtbdd_getstorm_rational_number_ptr(a);
+        storm_rational_number_ptr mb = mtbdd_getstorm_rational_number_ptr(b);
         storm_rational_number_ptr mres;
         if (storm_rational_number_is_zero(ma)) {
             mres = storm_rational_number_get_zero();
+        } else if (storm_rational_number_is_zero(mb)) {
+            mres = storm_rational_number_get_infinity();
         } else {
             storm_rational_number_ptr mb = mtbdd_getstorm_rational_number_ptr(b);
             mres = storm_rational_number_divide(ma, mb);