1 /*
  2  * Copyright (c) 1997, 2025, 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 #include "oops/arrayOop.hpp"
 25 #include "oops/oop.inline.hpp"
 26 #include "unittest.hpp"
 27 #include "utilities/globalDefinitions.hpp"
 28 
 29 static bool check_max_length_overflow(BasicType type) {
 30   julong length = arrayOopDesc::max_array_length(type);
 31   julong bytes_per_element = type2aelembytes(type);
 32   julong bytes = length * bytes_per_element
 33           + arrayOopDesc::base_offset_in_bytes(type);
 34   return (julong) (size_t) bytes == bytes;
 35 }
 36 
 37 TEST_VM(arrayOopDesc, boolean) {
 38   ASSERT_PRED1(check_max_length_overflow, T_BOOLEAN);
 39 }
 40 
 41 TEST_VM(arrayOopDesc, char) {
 42   ASSERT_PRED1(check_max_length_overflow, T_CHAR);
 43 }
 44 
 45 TEST_VM(arrayOopDesc, float) {
 46   ASSERT_PRED1(check_max_length_overflow, T_FLOAT);
 47 }
 48 
 49 TEST_VM(arrayOopDesc, double) {
 50   ASSERT_PRED1(check_max_length_overflow, T_DOUBLE);
 51 }
 52 
 53 TEST_VM(arrayOopDesc, byte) {
 54   ASSERT_PRED1(check_max_length_overflow, T_BYTE);
 55 }
 56 
 57 TEST_VM(arrayOopDesc, short) {
 58   ASSERT_PRED1(check_max_length_overflow, T_SHORT);
 59 }
 60 
 61 TEST_VM(arrayOopDesc, int) {
 62   ASSERT_PRED1(check_max_length_overflow, T_INT);
 63 }
 64 
 65 TEST_VM(arrayOopDesc, long) {
 66   ASSERT_PRED1(check_max_length_overflow, T_LONG);
 67 }
 68 
 69 TEST_VM(arrayOopDesc, object) {
 70   ASSERT_PRED1(check_max_length_overflow, T_OBJECT);
 71 }
 72 
 73 TEST_VM(arrayOopDesc, array) {
 74   ASSERT_PRED1(check_max_length_overflow, T_ARRAY);
 75 }
 76 
 77 TEST_VM(arrayOopDesc, narrowOop) {
 78   ASSERT_PRED1(check_max_length_overflow, T_NARROWOOP);
 79 }
 80 // T_VOID and T_ADDRESS are not supported by max_array_length()
 81 
 82 TEST_VM(arrayOopDesc, base_offset) {
 83 #ifdef _LP64
 84   if (UseCompactObjectHeaders) {
 85     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BOOLEAN), 12);
 86     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BYTE),    12);
 87     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_SHORT),   12);
 88     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_CHAR),    12);
 89     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_INT),     12);
 90     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_FLOAT),   12);
 91     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_LONG),    16);
 92     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_DOUBLE),  16);
 93     if (UseCompressedOops) {
 94       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT), 12);
 95       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),  12);
 96     } else {
 97       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT), 16);
 98       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),  16);
 99     }
100   } else if (UseCompressedClassPointers) {
101     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BOOLEAN), 16);
102     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BYTE),    16);
103     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_SHORT),   16);
104     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_CHAR),    16);
105     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_INT),     16);
106     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_FLOAT),   16);
107     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_LONG),    16);
108     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_DOUBLE),  16);
109     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT),  16);
110     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),   16);
111   } else {
112     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BOOLEAN), 20);
113     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BYTE),    20);
114     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_SHORT),   20);
115     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_CHAR),    20);
116     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_INT),     20);
117     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_FLOAT),   20);
118     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_LONG),    24);
119     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_DOUBLE),  24);
120     if (UseCompressedOops) {
121       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT), 20);
122       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),  20);
123     } else {
124       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT), 24);
125       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),  24);
126     }
127   }
128 #else
129   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BOOLEAN), 12);
130   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BYTE),    12);
131   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_SHORT),   12);
132   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_CHAR),    12);
133   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_INT),     12);
134   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_FLOAT),   12);
135   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_LONG),    16);
136   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_DOUBLE),  16);
137   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT),  12);
138   EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),   12);
139 #endif
140 }