335   }
 336   static bool layout_helper_is_objArray(jint lh) {
 337     // _lh_array_tag_obj_value == (lh >> _lh_array_tag_shift);
 338     return (jint)lh < (jint)(_lh_array_tag_type_value << _lh_array_tag_shift);
 339   }
 340   static int layout_helper_header_size(jint lh) {
 341     assert(lh < (jint)_lh_neutral_value, "must be array");
 342     int hsize = (lh >> _lh_header_size_shift) & _lh_header_size_mask;
 343     assert(hsize > 0 && hsize < (int)sizeof(oopDesc)*3, "sanity");
 344     return hsize;
 345   }
 346   static BasicType layout_helper_element_type(jint lh) {
 347     assert(lh < (jint)_lh_neutral_value, "must be array");
 348     int btvalue = (lh >> _lh_element_type_shift) & _lh_element_type_mask;
 349     assert(btvalue >= T_BOOLEAN && btvalue <= T_OBJECT, "sanity");
 350     return (BasicType) btvalue;
 351   }
 352   static int layout_helper_log2_element_size(jint lh) {
 353     assert(lh < (jint)_lh_neutral_value, "must be array");
 354     int l2esz = (lh >> _lh_log2_element_size_shift) & _lh_log2_element_size_mask;
 355     assert(l2esz <= LogBitsPerLong, "sanity");

 356     return l2esz;
 357   }
 358   static jint array_layout_helper(jint tag, int hsize, BasicType etype, int log2_esize) {
 359     return (tag        << _lh_array_tag_shift)
 360       |    (hsize      << _lh_header_size_shift)
 361       |    ((int)etype << _lh_element_type_shift)
 362       |    (log2_esize << _lh_log2_element_size_shift);
 363   }
 364   static jint instance_layout_helper(jint size, bool slow_path_flag) {
 365     return (size << LogHeapWordSize)
 366       |    (slow_path_flag ? _lh_instance_slow_path_bit : 0);
 367   }
 368   static int layout_helper_to_size_helper(jint lh) {
 369     assert(lh > (jint)_lh_neutral_value, "must be instance");
 370     // Note that the following expression discards _lh_instance_slow_path_bit.
 371     return lh >> LogHeapWordSize;
 372   }
 373   // Out-of-line version computes everything based on the etype:
 374   static jint array_layout_helper(BasicType etype);
 375 

 335   }
 336   static bool layout_helper_is_objArray(jint lh) {
 337     // _lh_array_tag_obj_value == (lh >> _lh_array_tag_shift);
 338     return (jint)lh < (jint)(_lh_array_tag_type_value << _lh_array_tag_shift);
 339   }
 340   static int layout_helper_header_size(jint lh) {
 341     assert(lh < (jint)_lh_neutral_value, "must be array");
 342     int hsize = (lh >> _lh_header_size_shift) & _lh_header_size_mask;
 343     assert(hsize > 0 && hsize < (int)sizeof(oopDesc)*3, "sanity");
 344     return hsize;
 345   }
 346   static BasicType layout_helper_element_type(jint lh) {
 347     assert(lh < (jint)_lh_neutral_value, "must be array");
 348     int btvalue = (lh >> _lh_element_type_shift) & _lh_element_type_mask;
 349     assert(btvalue >= T_BOOLEAN && btvalue <= T_OBJECT, "sanity");
 350     return (BasicType) btvalue;
 351   }
 352   static int layout_helper_log2_element_size(jint lh) {
 353     assert(lh < (jint)_lh_neutral_value, "must be array");
 354     int l2esz = (lh >> _lh_log2_element_size_shift) & _lh_log2_element_size_mask;
 355     assert(l2esz <= LogBitsPerLong,
 356         err_msg("sanity. l2esz: 0x%x for lh: 0x%x", (uint)l2esz, (uint)lh));
 357     return l2esz;
 358   }
 359   static jint array_layout_helper(jint tag, int hsize, BasicType etype, int log2_esize) {
 360     return (tag        << _lh_array_tag_shift)
 361       |    (hsize      << _lh_header_size_shift)
 362       |    ((int)etype << _lh_element_type_shift)
 363       |    (log2_esize << _lh_log2_element_size_shift);
 364   }
 365   static jint instance_layout_helper(jint size, bool slow_path_flag) {
 366     return (size << LogHeapWordSize)
 367       |    (slow_path_flag ? _lh_instance_slow_path_bit : 0);
 368   }
 369   static int layout_helper_to_size_helper(jint lh) {
 370     assert(lh > (jint)_lh_neutral_value, "must be instance");
 371     // Note that the following expression discards _lh_instance_slow_path_bit.
 372     return lh >> LogHeapWordSize;
 373   }
 374   // Out-of-line version computes everything based on the etype:
 375   static jint array_layout_helper(BasicType etype);
 376