1 /*
   2  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 
  27 /////////////// Unit tests ///////////////
  28 
  29 #ifndef PRODUCT
  30 
  31 #include "oops/arrayOop.hpp"
  32 #include "utilities/globalDefinitions.hpp"
  33 // Unit tests
  34 
  35 bool arrayOopDesc::check_max_length_overflow(BasicType type) {
  36   julong length = max_array_length(type);
  37   julong bytes_per_element = type2aelembytes(type);
  38   julong bytes = length * bytes_per_element + header_size_in_bytes();
  39   return (bytes - header_size_in_bytes()) / bytes_per_element == length;
  40 }
  41 
  42 bool arrayOopDesc::test_max_array_length() {
  43   tty->print_cr("test_max_array_length");
  44   
  45   assert(check_max_length_overflow(T_BOOLEAN), "size_t overflow for boolean array");
  46   assert(check_max_length_overflow(T_CHAR), "size_t overflow for char array");
  47   assert(check_max_length_overflow(T_FLOAT), "size_t overflow for float array");
  48   assert(check_max_length_overflow(T_DOUBLE), "size_t overflow for double array");
  49   assert(check_max_length_overflow(T_BYTE), "size_t overflow for byte array");
  50   assert(check_max_length_overflow(T_SHORT), "size_t overflow for short array");
  51   assert(check_max_length_overflow(T_INT), "size_t overflow for int array");
  52   assert(check_max_length_overflow(T_LONG), "size_t overflow for long array");
  53   assert(check_max_length_overflow(T_OBJECT), "size_t overflow for object array");
  54   assert(check_max_length_overflow(T_ARRAY), "size_t overflow for array array");
  55   assert(check_max_length_overflow(T_NARROWOOP), "size_t overflow for narrowOop array");
  56 
  57   // T_VOID and T_ADDRESS are not supported by max_array_length()
  58 
  59   return true;
  60 }
  61 
  62 
  63 #endif //PRODUCT