JACOBIN-563 Finished logic for handling arrays in CHECKCAST. Now need…

…s testing.

src/jvm/runUtils.go

@@ -522,7 +522,32 @@ func checkcastArray(obj *object.Object, className string) bool {
  return className == "java/lang/Object"
  }
 
- return false
+ // If S (obj) is an array type SC[], that is, an array of components of type SC,
+ // if T is an array type TC[], that is, an array of components of type TC,
+ // then one of the following must be true:
+ // > TC and SC are the same primitive type.
+ objArrayType := object.GetArrayType(*sptr)
+ classArrayType := object.GetArrayType(className)
+ if !strings.HasPrefix(objArrayType, "L") && // if both array types are primitives
+ !strings.HasPrefix(classArrayType, "L") {
+ if objArrayType == classArrayType { // are they the same primitive?
+ return true
+ }
+ }
+
+ // we now know both types are arrays of references, so the objects
+ // referred to must be castable:
+ // If TC and SC are reference types, and type SC can be cast to TC by
+ // recursive application of these rules.
+ rawObjArrayType, _ := strings.CutPrefix(objArrayType, "L")
+ rawObjArrayType = strings.TrimSuffix(rawObjArrayType, ";")
+ rawClassArrayType, _ := strings.CutPrefix(classArrayType, "L")
+ rawClassArrayType = strings.TrimSuffix(rawClassArrayType, ";")
+ if rawObjArrayType == classArrayType || rawClassArrayType == "java/lang/Object" {
+ return true
+ } else {
+ return isClassAaSublclassOfB(obj.KlassName, stringPool.GetStringIndex(&className))
+ }
 }
 
 func checkcastInterface(obj *object.Object, className string) bool {