1 /*
   2  * Copyright (c) 1999, 2017, 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 #ifndef OS_CPU_LINUX_X86_VM_ATOMIC_LINUX_X86_HPP
  26 #define OS_CPU_LINUX_X86_VM_ATOMIC_LINUX_X86_HPP
  27 
  28 // Implementation of class atomic
  29 
  30 inline void Atomic::store    (jbyte    store_value, jbyte*    dest) { *dest = store_value; }
  31 inline void Atomic::store    (jshort   store_value, jshort*   dest) { *dest = store_value; }
  32 inline void Atomic::store    (jint     store_value, jint*     dest) { *dest = store_value; }
  33 inline void Atomic::store_ptr(intptr_t store_value, intptr_t* dest) { *dest = store_value; }
  34 inline void Atomic::store_ptr(void*    store_value, void*     dest) { *(void**)dest = store_value; }
  35 
  36 inline void Atomic::store    (jbyte    store_value, volatile jbyte*    dest) { *dest = store_value; }
  37 inline void Atomic::store    (jshort   store_value, volatile jshort*   dest) { *dest = store_value; }
  38 inline void Atomic::store    (jint     store_value, volatile jint*     dest) { *dest = store_value; }
  39 inline void Atomic::store_ptr(intptr_t store_value, volatile intptr_t* dest) { *dest = store_value; }
  40 inline void Atomic::store_ptr(void*    store_value, volatile void*     dest) { *(void* volatile *)dest = store_value; }
  41 
  42 
  43 inline jint     Atomic::add    (jint     add_value, volatile jint*     dest) {
  44   jint addend = add_value;
  45   __asm__ volatile (  "lock xaddl %0,(%2)"
  46                     : "=r" (addend)
  47                     : "0" (addend), "r" (dest)
  48                     : "cc", "memory");
  49   return addend + add_value;
  50 }
  51 
  52 inline void Atomic::inc    (volatile jint*     dest) {
  53   __asm__ volatile (  "lock addl $1,(%0)" :
  54                     : "r" (dest) : "cc", "memory");
  55 }
  56 
  57 inline void Atomic::inc_ptr(volatile void*     dest) {
  58   inc_ptr((volatile intptr_t*)dest);
  59 }
  60 
  61 inline void Atomic::dec    (volatile jint*     dest) {
  62   __asm__ volatile (  "lock subl $1,(%0)" :
  63                     : "r" (dest) : "cc", "memory");
  64 }
  65 
  66 inline void Atomic::dec_ptr(volatile void*     dest) {
  67   dec_ptr((volatile intptr_t*)dest);
  68 }
  69 
  70 inline jint     Atomic::xchg    (jint     exchange_value, volatile jint*     dest) {
  71   __asm__ volatile (  "xchgl (%2),%0"
  72                     : "=r" (exchange_value)
  73                     : "0" (exchange_value), "r" (dest)
  74                     : "memory");
  75   return exchange_value;
  76 }
  77 
  78 inline void*    Atomic::xchg_ptr(void*    exchange_value, volatile void*     dest) {
  79   return (void*)xchg_ptr((intptr_t)exchange_value, (volatile intptr_t*)dest);
  80 }
  81 
  82 template<>
  83 template<typename T>
  84 inline T Atomic::PlatformCmpxchg<1>::operator()(T exchange_value,
  85                                                 T volatile* dest,
  86                                                 T compare_value,
  87                                                 cmpxchg_memory_order /* order */) const {
  88   __asm__ volatile ("lock cmpxchgb %1,(%3)"
  89                     : "=a" (exchange_value)
  90                     : "q" (exchange_value), "a" (compare_value), "r" (dest)
  91                     : "cc", "memory");
  92   return exchange_value;
  93 }
  94 
  95 template<>
  96 template<typename T>
  97 inline T Atomic::PlatformCmpxchg<4>::operator()(T exchange_value,
  98                                                 T volatile* dest,
  99                                                 T compare_value,
 100                                                 cmpxchg_memory_order /* order */) const {
 101   __asm__ volatile ("lock cmpxchgl %1,(%3)"
 102                     : "=a" (exchange_value)
 103                     : "r" (exchange_value), "a" (compare_value), "r" (dest)
 104                     : "cc", "memory");
 105   return exchange_value;
 106 }
 107 
 108 #ifdef AMD64
 109 inline void Atomic::store    (jlong    store_value, jlong*    dest) { *dest = store_value; }
 110 inline void Atomic::store    (jlong    store_value, volatile jlong*    dest) { *dest = store_value; }
 111 
 112 inline intptr_t Atomic::add_ptr(intptr_t add_value, volatile intptr_t* dest) {
 113   intptr_t addend = add_value;
 114   __asm__ __volatile__ ("lock xaddq %0,(%2)"
 115                         : "=r" (addend)
 116                         : "0" (addend), "r" (dest)
 117                         : "cc", "memory");
 118   return addend + add_value;
 119 }
 120 
 121 inline void*    Atomic::add_ptr(intptr_t add_value, volatile void*     dest) {
 122   return (void*)add_ptr(add_value, (volatile intptr_t*)dest);
 123 }
 124 
 125 inline void Atomic::inc_ptr(volatile intptr_t* dest) {
 126   __asm__ __volatile__ ("lock addq $1,(%0)"
 127                         :
 128                         : "r" (dest)
 129                         : "cc", "memory");
 130 }
 131 
 132 inline void Atomic::dec_ptr(volatile intptr_t* dest) {
 133   __asm__ __volatile__ ("lock subq $1,(%0)"
 134                         :
 135                         : "r" (dest)
 136                         : "cc", "memory");
 137 }
 138 
 139 inline intptr_t Atomic::xchg_ptr(intptr_t exchange_value, volatile intptr_t* dest) {
 140   __asm__ __volatile__ ("xchgq (%2),%0"
 141                         : "=r" (exchange_value)
 142                         : "0" (exchange_value), "r" (dest)
 143                         : "memory");
 144   return exchange_value;
 145 }
 146 
 147 template<>
 148 template<typename T>
 149 inline T Atomic::PlatformCmpxchg<8>::operator()(T exchange_value,
 150                                                 T volatile* dest,
 151                                                 T compare_value,
 152                                                 cmpxchg_memory_order /* order */) const {
 153   __asm__ __volatile__ ("lock cmpxchgq %1,(%3)"
 154                         : "=a" (exchange_value)
 155                         : "r" (exchange_value), "a" (compare_value), "r" (dest)
 156                         : "cc", "memory");
 157   return exchange_value;
 158 }
 159 
 160 inline jlong Atomic::load(const volatile jlong* src) { return *src; }
 161 
 162 #else // !AMD64
 163 
 164 inline intptr_t Atomic::add_ptr(intptr_t add_value, volatile intptr_t* dest) {
 165   return (intptr_t)Atomic::add((jint)add_value, (volatile jint*)dest);
 166 }
 167 
 168 inline void*    Atomic::add_ptr(intptr_t add_value, volatile void*     dest) {
 169   return (void*)Atomic::add((jint)add_value, (volatile jint*)dest);
 170 }
 171 
 172 
 173 inline void Atomic::inc_ptr(volatile intptr_t* dest) {
 174   inc((volatile jint*)dest);
 175 }
 176 
 177 inline void Atomic::dec_ptr(volatile intptr_t* dest) {
 178   dec((volatile jint*)dest);
 179 }
 180 
 181 inline intptr_t Atomic::xchg_ptr(intptr_t exchange_value, volatile intptr_t* dest) {
 182   return (intptr_t)xchg((jint)exchange_value, (volatile jint*)dest);
 183 }
 184 
 185 extern "C" {
 186   // defined in linux_x86.s
 187   jlong _Atomic_cmpxchg_long(jlong, volatile jlong*, jlong);
 188   void _Atomic_move_long(const volatile jlong* src, volatile jlong* dst);
 189 }
 190 
 191 template<>
 192 template<typename T>
 193 inline T Atomic::PlatformCmpxchg<8>::operator()(T exchange_value,
 194                                                 T volatile* dest,
 195                                                 T compare_value,
 196                                                 cmpxchg_memory_order order) const {
 197   return cmpxchg_using_stub<jlong>(_Atomic_cmpxchg_long, exchange_value, dest, compare_value);
 198 }
 199 
 200 inline jlong Atomic::load(const volatile jlong* src) {
 201   volatile jlong dest;
 202   _Atomic_move_long(src, &dest);
 203   return dest;
 204 }
 205 
 206 inline void Atomic::store(jlong store_value, jlong* dest) {
 207   _Atomic_move_long((volatile jlong*)&store_value, (volatile jlong*)dest);
 208 }
 209 
 210 inline void Atomic::store(jlong store_value, volatile jlong* dest) {
 211   _Atomic_move_long((volatile jlong*)&store_value, dest);
 212 }
 213 
 214 #endif // AMD64
 215 
 216 #endif // OS_CPU_LINUX_X86_VM_ATOMIC_LINUX_X86_HPP