atomic.hpp revision 1472:c18cbe5936b8
1/* 2 * Copyright (c) 1999, 2009, 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 25class Atomic : AllStatic { 26 public: 27 // Atomically store to a location 28 static void store (jbyte store_value, jbyte* dest); 29 static void store (jshort store_value, jshort* dest); 30 static void store (jint store_value, jint* dest); 31 static void store (jlong store_value, jlong* dest); 32 static void store_ptr(intptr_t store_value, intptr_t* dest); 33 static void store_ptr(void* store_value, void* dest); 34 35 static void store (jbyte store_value, volatile jbyte* dest); 36 static void store (jshort store_value, volatile jshort* dest); 37 static void store (jint store_value, volatile jint* dest); 38 static void store (jlong store_value, volatile jlong* dest); 39 static void store_ptr(intptr_t store_value, volatile intptr_t* dest); 40 static void store_ptr(void* store_value, volatile void* dest); 41 42 static jlong load(volatile jlong* src); 43 44 // Atomically add to a location, return updated value 45 static jint add (jint add_value, volatile jint* dest); 46 static intptr_t add_ptr(intptr_t add_value, volatile intptr_t* dest); 47 static void* add_ptr(intptr_t add_value, volatile void* dest); 48 49 // Atomically increment location 50 static void inc (volatile jint* dest); 51 static void inc_ptr(volatile intptr_t* dest); 52 static void inc_ptr(volatile void* dest); 53 54 // Atomically decrement a location 55 static void dec (volatile jint* dest); 56 static void dec_ptr(volatile intptr_t* dest); 57 static void dec_ptr(volatile void* dest); 58 59 // Performs atomic exchange of *dest with exchange_value. Returns old prior value of *dest. 60 static jint xchg(jint exchange_value, volatile jint* dest); 61 static unsigned int xchg(unsigned int exchange_value, 62 volatile unsigned int* dest); 63 64 static intptr_t xchg_ptr(intptr_t exchange_value, volatile intptr_t* dest); 65 static void* xchg_ptr(void* exchange_value, volatile void* dest); 66 67 // Performs atomic compare of *dest and compare_value, and exchanges *dest with exchange_value 68 // if the comparison succeeded. Returns prior value of *dest. Guarantees a two-way memory 69 // barrier across the cmpxchg. I.e., it's really a 'fence_cmpxchg_acquire'. 70 static jbyte cmpxchg (jbyte exchange_value, volatile jbyte* dest, jbyte compare_value); 71 static jint cmpxchg (jint exchange_value, volatile jint* dest, jint compare_value); 72 static jlong cmpxchg (jlong exchange_value, volatile jlong* dest, jlong compare_value); 73 74 static unsigned int cmpxchg(unsigned int exchange_value, 75 volatile unsigned int* dest, 76 unsigned int compare_value); 77 78 static intptr_t cmpxchg_ptr(intptr_t exchange_value, volatile intptr_t* dest, intptr_t compare_value); 79 static void* cmpxchg_ptr(void* exchange_value, volatile void* dest, void* compare_value); 80}; 81