src/share/vm/classfile/classFileParser.cpp

*** 3983,4000 ****
--- 3983,4009 ----
        Klass* klass = SystemDictionary::resolve_or_fail(signature,
                                                         Handle(THREAD, _loader_data->class_loader()),
                                                         _protection_domain, true, CHECK);
        assert(klass != NULL, "Sanity check");
        assert(klass->access_flags().is_value_type(), "Value type expected");
+       ValueKlass* vk = ValueKlass::cast(klass);
+       // Conditions to apply flattening or not should be defined
+       //in a single place
+       if (vk->size_helper() <= ValueArrayElemMaxFlatSize) {
          nonstatic_value_type_indexes[nonstatic_value_type_count] = fs.index();
          nonstatic_value_type_klasses[nonstatic_value_type_count] = klass;
          nonstatic_value_type_count++;
  
          ValueKlass* vklass = ValueKlass::cast(klass);
          if (vklass->contains_oops()) {
            value_type_oop_map_count += vklass->nonstatic_oop_map_count();
          }
+         fs.set_flattening(true);
+       } else {
+         value_type_oop_map_count++;
+         fs.set_flattening(false);
+       }
      }
    }
  
    // Total non-static fields count, including every contended field
    unsigned int nonstatic_fields_count = fac->count[NONSTATIC_DOUBLE] + fac->count[NONSTATIC_WORD] +
*** 4212,4222 ****
        case STATIC_DOUBLE:
          real_offset = next_static_double_offset;
          next_static_double_offset += BytesPerLong;
          break;
        case NONSTATIC_VALUETYPE:
!       {
          Klass* klass = nonstatic_value_type_klasses[next_value_type_index];
          assert(klass != NULL, "Klass should have been loaded and resolved earlier");
          assert(klass->access_flags().is_value_type(),"Must be a value type");
          ValueKlass* vklass = ValueKlass::cast(klass);
          real_offset = next_nonstatic_valuetype_offset;
--- 4221,4231 ----
        case STATIC_DOUBLE:
          real_offset = next_static_double_offset;
          next_static_double_offset += BytesPerLong;
          break;
        case NONSTATIC_VALUETYPE:
!         if (fs.is_flatten()) {
            Klass* klass = nonstatic_value_type_klasses[next_value_type_index];
            assert(klass != NULL, "Klass should have been loaded and resolved earlier");
            assert(klass->access_flags().is_value_type(),"Must be a value type");
            ValueKlass* vklass = ValueKlass::cast(klass);
            real_offset = next_nonstatic_valuetype_offset;
*** 4232,4243 ****
            while (map < last_map) {
              nonstatic_oop_maps->add(map->offset() + diff, map->count());
              map++;
            }
          }
-       }
        break;
        case NONSTATIC_OOP:
          if( nonstatic_oop_space_count > 0 ) {
            real_offset = nonstatic_oop_space_offset;
            nonstatic_oop_space_offset += heapOopSize;
            nonstatic_oop_space_count  -= 1;
--- 4241,4254 ----
              while (map < last_map) {
                nonstatic_oop_maps->add(map->offset() + diff, map->count());
                map++;
              }
            }
            break;
+         } else {
+           // Fall through
+         }
        case NONSTATIC_OOP:
          if( nonstatic_oop_space_count > 0 ) {
            real_offset = nonstatic_oop_space_offset;
            nonstatic_oop_space_offset += heapOopSize;
            nonstatic_oop_space_count  -= 1;