src/share/vm/oops/klass.hpp

*** 77,87 ****
    //
    // For arrays, layout helper is a negative number, containing four
    // distinct bytes, as follows:
    //    MSB:[tag, hsz, ebt, log2(esz)]:LSB
    // where:
!   //    tag is 0x80 if the elements are oops, 0xC0 if non-oops
    //    hsz is array header size in bytes (i.e., offset of first element)
    //    ebt is the BasicType of the elements
    //    esz is the element size in bytes
    // This packed word is arranged so as to be quickly unpacked by the
    // various fast paths that use the various subfields.
--- 77,87 ----
    //
    // For arrays, layout helper is a negative number, containing four
    // distinct bytes, as follows:
    //    MSB:[tag, hsz, ebt, log2(esz)]:LSB
    // where:
!   //    tag is 0x80 if the elements are oops, 0xC0 if non-oops, 0xA0 if value types
    //    hsz is array header size in bytes (i.e., offset of first element)
    //    ebt is the BasicType of the elements
    //    esz is the element size in bytes
    // This packed word is arranged so as to be quickly unpacked by the
    // various fast paths that use the various subfields.
*** 314,330 ****
      _lh_element_type_shift      = BitsPerByte*1,
      _lh_element_type_mask       = right_n_bits(BitsPerByte),  // shifted mask
      _lh_header_size_shift       = BitsPerByte*2,
      _lh_header_size_mask        = right_n_bits(BitsPerByte),  // shifted mask
  
!     // Additional array type bits
!     _lh_valuetype_bit         = 29, // maybe objArray or valueArrayOop
! 
!     _lh_array_tag_bits            = 2,
      _lh_array_tag_shift           = BitsPerInt - _lh_array_tag_bits,
!     _lh_array_tag_type_value      = ~0x00,  // 0xC0000000 >> 30
!     _lh_array_tag_obj_value       = ~0x01   // 0x80000000 >> 30
    };
  
    static int layout_helper_size_in_bytes(jint lh) {
      assert(lh > (jint)_lh_neutral_value, "must be instance");
      return (int) lh & ~_lh_instance_slow_path_bit;
--- 314,328 ----
      _lh_element_type_shift      = BitsPerByte*1,
      _lh_element_type_mask       = right_n_bits(BitsPerByte),  // shifted mask
      _lh_header_size_shift       = BitsPerByte*2,
      _lh_header_size_mask        = right_n_bits(BitsPerByte),  // shifted mask
  
!     _lh_array_tag_bits            = 3,
      _lh_array_tag_shift           = BitsPerInt - _lh_array_tag_bits,
!     _lh_array_tag_type_value      = ~0x3,  // bits ~100 compare as int, ie. sign extended
!     _lh_array_tag_vt_value        = ~0x2,  // bits ~101
!     _lh_array_tag_obj_value       = ~0x1,  // bits ~110
    };
  
    static int layout_helper_size_in_bytes(jint lh) {
      assert(lh > (jint)_lh_neutral_value, "must be instance");
      return (int) lh & ~_lh_instance_slow_path_bit;
*** 344,354 ****
    }
    static bool layout_helper_is_objArray(jint lh) {
      return _lh_array_tag_obj_value == (lh >> _lh_array_tag_shift);
    }
    static bool layout_helper_is_valueArray(jint lh) {
!     return (lh >> _lh_valuetype_bit) & 1;
    }
    static int layout_helper_header_size(jint lh) {
      assert(lh < (jint)_lh_neutral_value, "must be array");
      int hsize = (lh >> _lh_header_size_shift) & _lh_header_size_mask;
      assert(hsize > 0 && hsize < (int)sizeof(oopDesc)*3, "sanity");
--- 342,352 ----
    }
    static bool layout_helper_is_objArray(jint lh) {
      return _lh_array_tag_obj_value == (lh >> _lh_array_tag_shift);
    }
    static bool layout_helper_is_valueArray(jint lh) {
!     return _lh_array_tag_vt_value == (lh >> _lh_array_tag_shift);
    }
    static int layout_helper_header_size(jint lh) {
      assert(lh < (jint)_lh_neutral_value, "must be array");
      int hsize = (lh >> _lh_header_size_shift) & _lh_header_size_mask;
      assert(hsize > 0 && hsize < (int)sizeof(oopDesc)*3, "sanity");