1 /* 2 * Copyright 2012, 2015 SAP AG. 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 26 #ifndef OS_AIX_VM_MISC_AIX_HPP 27 #define OS_AIX_VM_MISC_AIX_HPP 28 29 /* misc_aix.hpp, misc_aix.cpp: convenience functions needed for the OpenJDK AIX 30 * port */ 31 #include "utilities/globalDefinitions.hpp" 32 33 #include <pthread.h> 34 35 #define assert0(b) assert( (b), "" ) 36 #define guarantee0(b) assert( (b), "" ) 37 template <class T1, class T2> bool is_aligned_to(T1 what, T2 alignment) { 38 return ( ((uintx)(what)) & (((uintx)(alignment)) - 1) ) == 0 ? true : false; 39 } 40 41 // CritSect: simple critical section implementation using pthread mutexes 42 namespace MiscUtils { 43 typedef pthread_mutex_t critsect_t; 44 45 void init_critsect(MiscUtils::critsect_t* cs); 46 void free_critsect(MiscUtils::critsect_t* cs); 47 void enter_critsect(MiscUtils::critsect_t* cs); 48 void leave_critsect(MiscUtils::critsect_t* cs); 49 50 // Need to wrap this in an object because we need to dynamically initialize 51 // critical section (because of windows, where there is no way to initialize 52 // a CRITICAL_SECTION statically. On Unix, we could use 53 // PTHREAD_MUTEX_INITIALIZER) 54 55 // Note: The critical section does NOT get cleaned up in the destructor. That is 56 // by design: the CritSect class is only ever used as global objects whose 57 // lifetime spans the whole VM life; in that context we don't want the lock to 58 // be cleaned up when global C++ objects are destroyed, but to continue to work 59 // correctly right to the very end of the process life. 60 class CritSect { 61 critsect_t _cs; 62 public: 63 CritSect() { init_critsect(&_cs); } 64 //~CritSect() { free_critsect(&_cs); } 65 void enter() { enter_critsect(&_cs); } 66 void leave() { leave_critsect(&_cs); } 67 }; 68 69 class AutoCritSect { 70 CritSect* const _pcsobj; 71 public: 72 AutoCritSect(CritSect* pcsobj) 73 : _pcsobj(pcsobj) 74 { 75 _pcsobj->enter(); 76 } 77 ~AutoCritSect() { 78 _pcsobj->leave(); 79 } 80 }; 81 82 // Returns true if pointer can be dereferenced without triggering a segment 83 // violation. Returns false if pointer is invalid. 84 // Note: Depends on stub routines; prior to stub routine generation, will 85 // always return true. Use CanUseSafeFetch32 to handle this case. 86 bool is_readable_pointer(const void* p); 87 88 } 89 90 #endif // OS_AIX_VM_MISC_AIX_HPP 91