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   STATIC_ASSERT(1 == sizeof(T));
  89   __asm__ volatile ("lock cmpxchgb %1,(%3)"
  90                     : "=a" (exchange_value)
  91                     : "q" (exchange_value), "a" (compare_value), "r" (dest)
  92                     : "cc", "memory");
  93   return exchange_value;
  94 }
  95 
  96 template<>
  97 template<typename T>
  98 inline T Atomic::PlatformCmpxchg<4>::operator()(T exchange_value,
  99                                                 T volatile* dest,
 100                                                 T compare_value,
 101                                                 cmpxchg_memory_order /* order */) const {
 102   STATIC_ASSERT(4 == sizeof(T));
 103   __asm__ volatile ("lock cmpxchgl %1,(%3)"
 104                     : "=a" (exchange_value)
 105                     : "r" (exchange_value), "a" (compare_value), "r" (dest)
 106                     : "cc", "memory");
 107   return exchange_value;
 108 }
 109 
 110 #ifdef AMD64
 111 inline void Atomic::store    (jlong    store_value, jlong*    dest) { *dest = store_value; }
 112 inline void Atomic::store    (jlong    store_value, volatile jlong*    dest) { *dest = store_value; }
 113 
 114 inline intptr_t Atomic::add_ptr(intptr_t add_value, volatile intptr_t* dest) {
 115   intptr_t addend = add_value;
 116   __asm__ __volatile__ ("lock xaddq %0,(%2)"
 117                         : "=r" (addend)
 118                         : "0" (addend), "r" (dest)
 119                         : "cc", "memory");
 120   return addend + add_value;
 121 }
 122 
 123 inline void*    Atomic::add_ptr(intptr_t add_value, volatile void*     dest) {
 124   return (void*)add_ptr(add_value, (volatile intptr_t*)dest);
 125 }
 126 
 127 inline void Atomic::inc_ptr(volatile intptr_t* dest) {
 128   __asm__ __volatile__ ("lock addq $1,(%0)"
 129                         :
 130                         : "r" (dest)
 131                         : "cc", "memory");
 132 }
 133 
 134 inline void Atomic::dec_ptr(volatile intptr_t* dest) {
 135   __asm__ __volatile__ ("lock subq $1,(%0)"
 136                         :
 137                         : "r" (dest)
 138                         : "cc", "memory");
 139 }
 140 
 141 inline intptr_t Atomic::xchg_ptr(intptr_t exchange_value, volatile intptr_t* dest) {
 142   __asm__ __volatile__ ("xchgq (%2),%0"
 143                         : "=r" (exchange_value)
 144                         : "0" (exchange_value), "r" (dest)
 145                         : "memory");
 146   return exchange_value;
 147 }
 148 
 149 template<>
 150 template<typename T>
 151 inline T Atomic::PlatformCmpxchg<8>::operator()(T exchange_value,
 152                                                 T volatile* dest,
 153                                                 T compare_value,
 154                                                 cmpxchg_memory_order /* order */) const {
 155   STATIC_ASSERT(8 == sizeof(T));
 156   __asm__ __volatile__ ("lock cmpxchgq %1,(%3)"
 157                         : "=a" (exchange_value)
 158                         : "r" (exchange_value), "a" (compare_value), "r" (dest)
 159                         : "cc", "memory");
 160   return exchange_value;
 161 }
 162 
 163 inline jlong Atomic::load(const volatile jlong* src) { return *src; }
 164 
 165 #else // !AMD64
 166 
 167 inline intptr_t Atomic::add_ptr(intptr_t add_value, volatile intptr_t* dest) {
 168   return (intptr_t)Atomic::add((jint)add_value, (volatile jint*)dest);
 169 }
 170 
 171 inline void*    Atomic::add_ptr(intptr_t add_value, volatile void*     dest) {
 172   return (void*)Atomic::add((jint)add_value, (volatile jint*)dest);
 173 }
 174 
 175 
 176 inline void Atomic::inc_ptr(volatile intptr_t* dest) {
 177   inc((volatile jint*)dest);
 178 }
 179 
 180 inline void Atomic::dec_ptr(volatile intptr_t* dest) {
 181   dec((volatile jint*)dest);
 182 }
 183 
 184 inline intptr_t Atomic::xchg_ptr(intptr_t exchange_value, volatile intptr_t* dest) {
 185   return (intptr_t)xchg((jint)exchange_value, (volatile jint*)dest);
 186 }
 187 
 188 extern "C" {
 189   // defined in linux_x86.s
 190   jlong _Atomic_cmpxchg_long(jlong, volatile jlong*, jlong);
 191   void _Atomic_move_long(const volatile jlong* src, volatile jlong* dst);
 192 }
 193 
 194 template<>
 195 template<typename T>
 196 inline T Atomic::PlatformCmpxchg<8>::operator()(T exchange_value,
 197                                                 T volatile* dest,
 198                                                 T compare_value,
 199                                                 cmpxchg_memory_order order) const {
 200   STATIC_ASSERT(8 == sizeof(T));
 201   return cmpxchg_using_helper<jlong>(_Atomic_cmpxchg_long, exchange_value, dest, compare_value);
 202 }
 203 
 204 inline jlong Atomic::load(const volatile jlong* src) {
 205   volatile jlong dest;
 206   _Atomic_move_long(src, &dest);
 207   return dest;
 208 }
 209 
 210 inline void Atomic::store(jlong store_value, jlong* dest) {
 211   _Atomic_move_long((volatile jlong*)&store_value, (volatile jlong*)dest);
 212 }
 213 
 214 inline void Atomic::store(jlong store_value, volatile jlong* dest) {
 215   _Atomic_move_long((volatile jlong*)&store_value, dest);
 216 }
 217 
 218 #endif // AMD64
 219 
 220 #endif // OS_CPU_LINUX_X86_VM_ATOMIC_LINUX_X86_HPP