src/hotspot/share/c1/c1_Instruction.cpp

*** 112,131 ****
--- 112,172 ----
      return t->as_klass()->exact_klass();
    }
    return NULL;
  }
  
+ 
+ // FIXME -- make this obsolete. Use maybe_flattened_array() or check_flattened_array() instead.
  bool Instruction::is_flattened_array() const {
    if (ValueArrayFlatten) {
      ciType* type = declared_type();
      if (type != NULL && type->is_value_array_klass()) {
        ciValueKlass* element_klass = type->as_value_array_klass()->element_klass()->as_value_klass();
        if (!element_klass->is_loaded() || element_klass->flatten_array()) {
          // Assume that all unloaded value arrays are not flattenable. If they
          // turn out to be flattenable, we deoptimize on aaload/aastore.
+         // ^^^^ uugh -- this is ugly!
+         return true;
+       }
+     }
+   }
+ 
+   return false;
+ }
+ 
+ bool Instruction::is_loaded_flattened_array() const {
+   if (ValueArrayFlatten) {
+     ciType* type = declared_type();
+     if (type != NULL && type->is_value_array_klass()) {
+       ciValueKlass* element_klass = type->as_value_array_klass()->element_klass()->as_value_klass();
+       if (element_klass->is_loaded() && element_klass->flatten_array()) {
+         return true;
+       }
+     }
+   }
+ 
+   return false;
+ }
+ 
+ bool Instruction::maybe_flattened_array() const {
+   if (ValueArrayFlatten) {
+     ciType* type = declared_type();
+     if (type != NULL) {
+       if (type->is_value_array_klass()) {
+         ciValueKlass* element_klass = type->as_value_array_klass()->element_klass()->as_value_klass();
+         if (!element_klass->is_loaded() || element_klass->flatten_array()) {
+           // For unloaded value arrays, we will add a runtime check for flat-ness.
            return true;
          }
+       } else if (type->is_obj_array_klass()) {
+         ciKlass* element_klass = type->as_obj_array_klass()->element_klass();
+         if (element_klass->is_java_lang_Object()) {
+           // Array covariance (ValueType[] <: Object[])
+           // We will add a runtime check for flat-ness.
+           return true;
+         }
+       }
      }
    }
  
    return false;
  }