1 /* 2 * Copyright (c) 2023, Red Hat, Inc. All rights reserved. 3 * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26 #include "precompiled.hpp" 27 28 #ifdef _LP64 29 30 #include "oops/compressedKlass.hpp" 31 #include "utilities/globalDefinitions.hpp" 32 33 char* CompressedKlassPointers::reserve_address_space_for_compressed_classes(size_t size, bool aslr, bool optimize_for_zero_base) { 34 35 char* result = nullptr; 36 37 // Optimize for unscaled encoding; failing that, for zero-based encoding: 38 if (optimize_for_zero_base) { 39 result = reserve_address_space_for_unscaled_encoding(size, aslr); 40 if (result == nullptr) { 41 result = reserve_address_space_for_zerobased_encoding(size, aslr); 42 } 43 } // end: low-address reservation 44 45 // Nothing more to optimize for on x64. If base != 0, we will always emit the full 64-bit immediate. 46 return result; 47 } 48 49 #endif // _LP64 --- EOF ---