1 /*
   2  * Copyright (c) 2003, 2013, 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_ORDERACCESS_LINUX_X86_INLINE_HPP
  26 #define OS_CPU_LINUX_X86_VM_ORDERACCESS_LINUX_X86_INLINE_HPP
  27 
  28 #include "runtime/atomic.inline.hpp"
  29 #include "runtime/orderAccess.hpp"
  30 #include "runtime/os.hpp"
  31 #include "vm_version_x86.hpp"
  32 
  33 // Implementation of class OrderAccess.
  34 
  35 inline void OrderAccess::loadload()   { acquire(); }
  36 inline void OrderAccess::storestore() { release(); }
  37 inline void OrderAccess::loadstore()  { acquire(); }
  38 inline void OrderAccess::storeload()  { fence(); }
  39 
  40 inline void OrderAccess::acquire() {
  41   volatile intptr_t local_dummy;
  42 #ifdef AMD64
  43   __asm__ volatile ("movq 0(%%rsp), %0" : "=r" (local_dummy) : : "memory");
  44 #else
  45   __asm__ volatile ("movl 0(%%esp),%0" : "=r" (local_dummy) : : "memory");
  46 #endif // AMD64
  47 }
  48 
  49 inline void OrderAccess::release() {
  50   // Avoid hitting the same cache-line from
  51   // different threads.
  52   volatile jint local_dummy = 0;
  53 }
  54 
  55 inline void OrderAccess::fence() {
  56   if (os::is_MP()) {
  57     // always use locked addl since mfence is sometimes expensive
  58 #ifdef AMD64
  59     __asm__ volatile ("lock; addl $0,0(%%rsp)" : : : "cc", "memory");
  60 #else
  61     __asm__ volatile ("lock; addl $0,0(%%esp)" : : : "cc", "memory");
  62 #endif
  63   }
  64 }
  65 
  66 inline jbyte    OrderAccess::load_acquire(volatile jbyte*   p) { return *p; }
  67 inline jshort   OrderAccess::load_acquire(volatile jshort*  p) { return *p; }
  68 inline jint     OrderAccess::load_acquire(volatile jint*    p) { return *p; }
  69 inline jlong    OrderAccess::load_acquire(volatile jlong*   p) { return Atomic::load(p); }
  70 inline jubyte   OrderAccess::load_acquire(volatile jubyte*  p) { return *p; }
  71 inline jushort  OrderAccess::load_acquire(volatile jushort* p) { return *p; }
  72 inline juint    OrderAccess::load_acquire(volatile juint*   p) { return *p; }
  73 inline julong   OrderAccess::load_acquire(volatile julong*  p) { return Atomic::load((volatile jlong*)p); }
  74 inline jfloat   OrderAccess::load_acquire(volatile jfloat*  p) { return *p; }
  75 inline jdouble  OrderAccess::load_acquire(volatile jdouble* p) { return jdouble_cast(Atomic::load((volatile jlong*)p)); }
  76 
  77 inline intptr_t OrderAccess::load_ptr_acquire(volatile intptr_t*   p) { return *p; }
  78 inline void*    OrderAccess::load_ptr_acquire(volatile void*       p) { return *(void* volatile *)p; }
  79 inline void*    OrderAccess::load_ptr_acquire(const volatile void* p) { return *(void* const volatile *)p; }
  80 
  81 inline void     OrderAccess::release_store(volatile jbyte*   p, jbyte   v) { *p = v; }
  82 inline void     OrderAccess::release_store(volatile jshort*  p, jshort  v) { *p = v; }
  83 inline void     OrderAccess::release_store(volatile jint*    p, jint    v) { *p = v; }
  84 inline void     OrderAccess::release_store(volatile jlong*   p, jlong   v) { Atomic::store(v, p); }
  85 inline void     OrderAccess::release_store(volatile jubyte*  p, jubyte  v) { *p = v; }
  86 inline void     OrderAccess::release_store(volatile jushort* p, jushort v) { *p = v; }
  87 inline void     OrderAccess::release_store(volatile juint*   p, juint   v) { *p = v; }
  88 inline void     OrderAccess::release_store(volatile julong*  p, julong  v) { Atomic::store((jlong)v, (volatile jlong*)p); }
  89 inline void     OrderAccess::release_store(volatile jfloat*  p, jfloat  v) { *p = v; }
  90 inline void     OrderAccess::release_store(volatile jdouble* p, jdouble v) { release_store((volatile jlong *)p, jlong_cast(v)); }
  91 
  92 inline void     OrderAccess::release_store_ptr(volatile intptr_t* p, intptr_t v) { *p = v; }
  93 inline void     OrderAccess::release_store_ptr(volatile void*     p, void*    v) { *(void* volatile *)p = v; }
  94 
  95 inline void     OrderAccess::store_fence(jbyte*  p, jbyte  v) {
  96   __asm__ volatile (  "xchgb (%2),%0"
  97                     : "=q" (v)
  98                     : "0" (v), "r" (p)
  99                     : "memory");
 100 }
 101 inline void     OrderAccess::store_fence(jshort* p, jshort v) {
 102   __asm__ volatile (  "xchgw (%2),%0"
 103                     : "=r" (v)
 104                     : "0" (v), "r" (p)
 105                     : "memory");
 106 }
 107 inline void     OrderAccess::store_fence(jint*   p, jint   v) {
 108   __asm__ volatile (  "xchgl (%2),%0"
 109                     : "=r" (v)
 110                     : "0" (v), "r" (p)
 111                     : "memory");
 112 }
 113 
 114 inline void     OrderAccess::store_fence(jlong*   p, jlong   v) {
 115 #ifdef AMD64
 116   __asm__ __volatile__ ("xchgq (%2), %0"
 117                         : "=r" (v)
 118                         : "0" (v), "r" (p)
 119                         : "memory");
 120 #else
 121   *p = v; fence();
 122 #endif // AMD64
 123 }
 124 
 125 // AMD64 copied the bodies for the the signed version. 32bit did this. As long as the
 126 // compiler does the inlining this is simpler.
 127 inline void     OrderAccess::store_fence(jubyte*  p, jubyte  v) { store_fence((jbyte*)p,  (jbyte)v);  }
 128 inline void     OrderAccess::store_fence(jushort* p, jushort v) { store_fence((jshort*)p, (jshort)v); }
 129 inline void     OrderAccess::store_fence(juint*   p, juint   v) { store_fence((jint*)p,   (jint)v);   }
 130 inline void     OrderAccess::store_fence(julong*  p, julong  v) { store_fence((jlong*)p,  (jlong)v);  }
 131 inline void     OrderAccess::store_fence(jfloat*  p, jfloat  v) { *p = v; fence(); }
 132 inline void     OrderAccess::store_fence(jdouble* p, jdouble v) { store_fence((jlong*)p, jlong_cast(v)); }
 133 
 134 inline void     OrderAccess::store_ptr_fence(intptr_t* p, intptr_t v) {
 135 #ifdef AMD64
 136   __asm__ __volatile__ ("xchgq (%2), %0"
 137                         : "=r" (v)
 138                         : "0" (v), "r" (p)
 139                         : "memory");
 140 #else
 141   store_fence((jint*)p, (jint)v);
 142 #endif // AMD64
 143 }
 144 
 145 inline void     OrderAccess::store_ptr_fence(void**    p, void*    v) {
 146 #ifdef AMD64
 147   __asm__ __volatile__ ("xchgq (%2), %0"
 148                         : "=r" (v)
 149                         : "0" (v), "r" (p)
 150                         : "memory");
 151 #else
 152   store_fence((jint*)p, (jint)v);
 153 #endif // AMD64
 154 }
 155 
 156 // Must duplicate definitions instead of calling store_fence because we don't want to cast away volatile.
 157 inline void     OrderAccess::release_store_fence(volatile jbyte*  p, jbyte  v) {
 158   __asm__ volatile (  "xchgb (%2),%0"
 159                     : "=q" (v)
 160                     : "0" (v), "r" (p)
 161                     : "memory");
 162 }
 163 inline void     OrderAccess::release_store_fence(volatile jshort* p, jshort v) {
 164   __asm__ volatile (  "xchgw (%2),%0"
 165                     : "=r" (v)
 166                     : "0" (v), "r" (p)
 167                     : "memory");
 168 }
 169 inline void     OrderAccess::release_store_fence(volatile jint*   p, jint   v) {
 170   __asm__ volatile (  "xchgl (%2),%0"
 171                     : "=r" (v)
 172                     : "0" (v), "r" (p)
 173                     : "memory");
 174 }
 175 
 176 inline void     OrderAccess::release_store_fence(volatile jlong*   p, jlong   v) {
 177 #ifdef AMD64
 178   __asm__ __volatile__ (  "xchgq (%2), %0"
 179                           : "=r" (v)
 180                           : "0" (v), "r" (p)
 181                           : "memory");
 182 #else
 183   release_store(p, v); fence();
 184 #endif // AMD64
 185 }
 186 
 187 inline void     OrderAccess::release_store_fence(volatile jubyte*  p, jubyte  v) { release_store_fence((volatile jbyte*)p,  (jbyte)v);  }
 188 inline void     OrderAccess::release_store_fence(volatile jushort* p, jushort v) { release_store_fence((volatile jshort*)p, (jshort)v); }
 189 inline void     OrderAccess::release_store_fence(volatile juint*   p, juint   v) { release_store_fence((volatile jint*)p,   (jint)v);   }
 190 inline void     OrderAccess::release_store_fence(volatile julong*  p, julong  v) { release_store_fence((volatile jlong*)p,  (jlong)v);  }
 191 
 192 inline void     OrderAccess::release_store_fence(volatile jfloat*  p, jfloat  v) { *p = v; fence(); }
 193 inline void     OrderAccess::release_store_fence(volatile jdouble* p, jdouble v) { release_store_fence((volatile jlong*)p, jlong_cast(v)); }
 194 
 195 inline void     OrderAccess::release_store_ptr_fence(volatile intptr_t* p, intptr_t v) {
 196 #ifdef AMD64
 197   __asm__ __volatile__ (  "xchgq (%2), %0"
 198                           : "=r" (v)
 199                           : "0" (v), "r" (p)
 200                           : "memory");
 201 #else
 202   release_store_fence((volatile jint*)p, (jint)v);
 203 #endif // AMD64
 204 }
 205 inline void     OrderAccess::release_store_ptr_fence(volatile void*     p, void*    v) {
 206 #ifdef AMD64
 207   __asm__ __volatile__ (  "xchgq (%2), %0"
 208                           : "=r" (v)
 209                           : "0" (v), "r" (p)
 210                           : "memory");
 211 #else
 212   release_store_fence((volatile jint*)p, (jint)v);
 213 #endif // AMD64
 214 }
 215 
 216 #endif // OS_CPU_LINUX_X86_VM_ORDERACCESS_LINUX_X86_INLINE_HPP