l4/pkg/uclibc/lib/contrib/uclibc/libc/sysdeps/linux/sparc/bits/atomic.h

   1 /* Atomic operations.  sparc32 version.
   2    Copyright (C) 2003, 2004, 2006 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Jakub Jelinek <jakub@redhat.com>, 2003.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef _BITS_ATOMIC_H
  21 #define _BITS_ATOMIC_H  1
  22
  23 #include <stdint.h>
  24
  25 typedef int8_t atomic8_t;
  26 typedef uint8_t uatomic8_t;
  27 typedef int_fast8_t atomic_fast8_t;
  28 typedef uint_fast8_t uatomic_fast8_t;
  29
  30 typedef int16_t atomic16_t;
  31 typedef uint16_t uatomic16_t;
  32 typedef int_fast16_t atomic_fast16_t;
  33 typedef uint_fast16_t uatomic_fast16_t;
  34
  35 typedef int32_t atomic32_t;
  36 typedef uint32_t uatomic32_t;
  37 typedef int_fast32_t atomic_fast32_t;
  38 typedef uint_fast32_t uatomic_fast32_t;
  39
  40 typedef int64_t atomic64_t;
  41 typedef uint64_t uatomic64_t;
  42 typedef int_fast64_t atomic_fast64_t;
  43 typedef uint_fast64_t uatomic_fast64_t;
  44
  45 typedef intptr_t atomicptr_t;
  46 typedef uintptr_t uatomicptr_t;
  47 typedef intmax_t atomic_max_t;
  48 typedef uintmax_t uatomic_max_t;
  49
  50
  51 /* We have no compare and swap, just test and set.
  52    The following implementation contends on 64 global locks
  53    per library and assumes no variable will be accessed using atomic.h
  54    macros from two different libraries.  */
  55
  56 __make_section_unallocated
  57   (".gnu.linkonce.b.__sparc32_atomic_locks, \"aw\", %nobits");
  58
  59 volatile unsigned char __sparc32_atomic_locks[64]
  60   __attribute__ ((nocommon, section (".gnu.linkonce.b.__sparc32_atomic_locks"
  61                                      __sec_comment),
  62                   visibility ("hidden")));
  63
  64 #define __sparc32_atomic_do_lock(addr) \
  65   do                                                                  \
  66     {                                                                 \
  67       unsigned int __old_lock;                                        \
  68       unsigned int __idx = (((long) addr >> 2) ^ ((long) addr >> 12)) \
  69                            & 63;                                      \
  70       do                                                              \
  71         __asm__ __volatile__ ("ldstub %1, %0"                         \
  72                           : "=r" (__old_lock),                        \
  73                             "=m" (__sparc32_atomic_locks[__idx])      \
  74                           : "m" (__sparc32_atomic_locks[__idx])       \
  75                           : "memory");                                \
  76       while (__old_lock);                                             \
  77     }                                                                 \
  78   while (0)
  79
  80 #define __sparc32_atomic_do_unlock(addr) \
  81   do                                                                  \
  82     {                                                                 \
  83       __sparc32_atomic_locks[(((long) addr >> 2)                      \
  84                               ^ ((long) addr >> 12)) & 63] = 0;       \
  85       __asm__ __volatile__ ("" ::: "memory");                         \
  86     }                                                                 \
  87   while (0)
  88
  89 #define __sparc32_atomic_do_lock24(addr) \
  90   do                                                                  \
  91     {                                                                 \
  92       unsigned int __old_lock;                                        \
  93       do                                                              \
  94         __asm__ __volatile__ ("ldstub %1, %0"                         \
  95                           : "=r" (__old_lock), "=m" (*(addr))         \
  96                           : "m" (*(addr))                             \
  97                           : "memory");                                \
  98       while (__old_lock);                                             \
  99     }                                                                 \
 100   while (0)
 101
 102 #define __sparc32_atomic_do_unlock24(addr) \
 103   do                                                                  \
 104     {                                                                 \
 105       *(char *) (addr) = 0;                                           \
 106       __asm__ __volatile__ ("" ::: "memory");                         \
 107     }                                                                 \
 108   while (0)
 109
 110
 111 #ifndef SHARED
 112 # define __v9_compare_and_exchange_val_32_acq(mem, newval, oldval) \
 113 ({                                                                            \
 114   register __typeof (*(mem)) __acev_tmp __asm__ ("%g6");                              \
 115   register __typeof (mem) __acev_mem __asm__ ("%g1") = (mem);                 \
 116   register __typeof (*(mem)) __acev_oldval __asm__ ("%g5");                   \
 117   __acev_tmp = (newval);                                                      \
 118   __acev_oldval = (oldval);                                                   \
 119   /* .word 0xcde05005 is cas [%g1], %g5, %g6.  Can't use cas here though,     \
 120      because as will then mark the object file as V8+ arch.  */               \
 121   __asm__ __volatile__ (".word 0xcde05005"                                            \
 122                     : "+r" (__acev_tmp), "=m" (*__acev_mem)                   \
 123                     : "r" (__acev_oldval), "m" (*__acev_mem),                 \
 124                       "r" (__acev_mem) : "memory");                           \
 125   __acev_tmp; })
 126 #endif
 127
 128 /* The only basic operation needed is compare and exchange.  */
 129 #define __v7_compare_and_exchange_val_acq(mem, newval, oldval) \
 130   ({ __typeof (mem) __acev_memp = (mem);                              \
 131      __typeof (*mem) __acev_ret;                                      \
 132      __typeof (*mem) __acev_newval = (newval);                        \
 133                                                                       \
 134      __sparc32_atomic_do_lock (__acev_memp);                          \
 135      __acev_ret = *__acev_memp;                                       \
 136      if (__acev_ret == (oldval))                                      \
 137        *__acev_memp = __acev_newval;                                  \
 138      __sparc32_atomic_do_unlock (__acev_memp);                        \
 139      __acev_ret; })
 140
 141 #define __v7_compare_and_exchange_bool_acq(mem, newval, oldval) \
 142   ({ __typeof (mem) __aceb_memp = (mem);                              \
 143      int __aceb_ret;                                                  \
 144      __typeof (*mem) __aceb_newval = (newval);                        \
 145                                                                       \
 146      __sparc32_atomic_do_lock (__aceb_memp);                          \
 147      __aceb_ret = 0;                                                  \
 148      if (*__aceb_memp == (oldval))                                    \
 149        *__aceb_memp = __aceb_newval;                                  \
 150      else                                                             \
 151        __aceb_ret = 1;                                                \
 152      __sparc32_atomic_do_unlock (__aceb_memp);                        \
 153      __aceb_ret; })
 154
 155 #define __v7_exchange_acq(mem, newval) \
 156   ({ __typeof (mem) __acev_memp = (mem);                              \
 157      __typeof (*mem) __acev_ret;                                      \
 158      __typeof (*mem) __acev_newval = (newval);                        \
 159                                                                       \
 160      __sparc32_atomic_do_lock (__acev_memp);                          \
 161      __acev_ret = *__acev_memp;                                       \
 162      *__acev_memp = __acev_newval;                                    \
 163      __sparc32_atomic_do_unlock (__acev_memp);                        \
 164      __acev_ret; })
 165
 166 #define __v7_exchange_and_add(mem, value) \
 167   ({ __typeof (mem) __acev_memp = (mem);                              \
 168      __typeof (*mem) __acev_ret;                                      \
 169                                                                       \
 170      __sparc32_atomic_do_lock (__acev_memp);                          \
 171      __acev_ret = *__acev_memp;                                       \
 172      *__acev_memp = __acev_ret + (value);                             \
 173      __sparc32_atomic_do_unlock (__acev_memp);                        \
 174      __acev_ret; })
 175
 176 /* Special versions, which guarantee that top 8 bits of all values
 177    are cleared and use those bits as the ldstub lock.  */
 178 #define __v7_compare_and_exchange_val_24_acq(mem, newval, oldval) \
 179   ({ __typeof (mem) __acev_memp = (mem);                              \
 180      __typeof (*mem) __acev_ret;                                      \
 181      __typeof (*mem) __acev_newval = (newval);                        \
 182                                                                       \
 183      __sparc32_atomic_do_lock24 (__acev_memp);                        \
 184      __acev_ret = *__acev_memp & 0xffffff;                            \
 185      if (__acev_ret == (oldval))                                      \
 186        *__acev_memp = __acev_newval;                                  \
 187      else                                                             \
 188        __sparc32_atomic_do_unlock24 (__acev_memp);                    \
 189      __asm__ __volatile__ ("" ::: "memory");                          \
 190      __acev_ret; })
 191
 192 #define __v7_exchange_24_rel(mem, newval) \
 193   ({ __typeof (mem) __acev_memp = (mem);                              \
 194      __typeof (*mem) __acev_ret;                                      \
 195      __typeof (*mem) __acev_newval = (newval);                        \
 196                                                                       \
 197      __sparc32_atomic_do_lock24 (__acev_memp);                        \
 198      __acev_ret = *__acev_memp & 0xffffff;                            \
 199      *__acev_memp = __acev_newval;                                    \
 200      __asm__ __volatile__ ("" ::: "memory");                          \
 201      __acev_ret; })
 202
 203 #ifdef SHARED
 204
 205 /* When dynamically linked, we assume pre-v9 libraries are only ever
 206    used on pre-v9 CPU.  */
 207 # define __atomic_is_v9 0
 208
 209 # define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \
 210   __v7_compare_and_exchange_val_acq (mem, newval, oldval)
 211
 212 # define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
 213   __v7_compare_and_exchange_bool_acq (mem, newval, oldval)
 214
 215 # define atomic_exchange_acq(mem, newval) \
 216   __v7_exchange_acq (mem, newval)
 217
 218 # define atomic_exchange_and_add(mem, value) \
 219   __v7_exchange_and_add (mem, value)
 220
 221 # define atomic_compare_and_exchange_val_24_acq(mem, newval, oldval) \
 222   ({                                                                  \
 223      if (sizeof (*mem) != 4)                                          \
 224        abort ();                                                      \
 225      __v7_compare_and_exchange_val_24_acq (mem, newval, oldval); })
 226
 227 # define atomic_exchange_24_rel(mem, newval) \
 228   ({                                                                  \
 229      if (sizeof (*mem) != 4)                                          \
 230        abort ();                                                      \
 231      __v7_exchange_24_rel (mem, newval); })
 232
 233 #else
 234
 235
 236
 237 /*
 238    Here's what we'd like to do:
 239
 240    In libc.a/libpthread.a etc. we don't know if we'll be run on
 241    pre-v9 or v9 CPU.  To be interoperable with dynamically linked
 242    apps on v9 CPUs e.g. with process shared primitives, use cas insn
 243    on v9 CPUs and ldstub on pre-v9.
 244
 245    However, we have no good way to test at run time that I know of,
 246    so resort to the lowest common denominator (v7 ops) -austinf
 247  */
 248 #define __atomic_is_v9 0
 249
 250 # define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \
 251   ({                                                                  \
 252      __typeof (*mem) __acev_wret;                                     \
 253      if (sizeof (*mem) != 4)                                          \
 254        abort ();                                                      \
 255      if (__atomic_is_v9)                                              \
 256        __acev_wret                                                    \
 257          = __v9_compare_and_exchange_val_32_acq (mem, newval, oldval);\
 258      else                                                             \
 259        __acev_wret                                                    \
 260          = __v7_compare_and_exchange_val_acq (mem, newval, oldval);   \
 261      __acev_wret; })
 262
 263 # define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
 264   ({                                                                  \
 265      int __acev_wret;                                                 \
 266      if (sizeof (*mem) != 4)                                          \
 267        abort ();                                                      \
 268      if (__atomic_is_v9)                                              \
 269        {                                                              \
 270          __typeof (oldval) __acev_woldval = (oldval);                 \
 271          __acev_wret                                                  \
 272            = __v9_compare_and_exchange_val_32_acq (mem, newval,       \
 273                                                    __acev_woldval)    \
 274              != __acev_woldval;                                       \
 275        }                                                              \
 276      else                                                             \
 277        __acev_wret                                                    \
 278          = __v7_compare_and_exchange_bool_acq (mem, newval, oldval);  \
 279      __acev_wret; })
 280
 281 # define atomic_exchange_rel(mem, newval) \
 282   ({                                                                  \
 283      __typeof (*mem) __acev_wret;                                     \
 284      if (sizeof (*mem) != 4)                                          \
 285        abort ();                                                      \
 286      if (__atomic_is_v9)                                              \
 287        {                                                              \
 288          __typeof (mem) __acev_wmemp = (mem);                         \
 289          __typeof (*(mem)) __acev_wval = (newval);                    \
 290          do                                                           \
 291            __acev_wret = *__acev_wmemp;                               \
 292          while (unlikely                                              \
 293                   (__v9_compare_and_exchange_val_32_acq (__acev_wmemp,\
 294                                                          __acev_wval, \
 295                                                          __acev_wret) \
 296                    != __acev_wret));                                  \
 297        }                                                              \
 298      else                                                             \
 299        __acev_wret = __v7_exchange_acq (mem, newval);                 \
 300      __acev_wret; })
 301
 302 # define atomic_compare_and_exchange_val_24_acq(mem, newval, oldval) \
 303   ({                                                                  \
 304      __typeof (*mem) __acev_wret;                                     \
 305      if (sizeof (*mem) != 4)                                          \
 306        abort ();                                                      \
 307      if (__atomic_is_v9)                                              \
 308        __acev_wret                                                    \
 309          = __v9_compare_and_exchange_val_32_acq (mem, newval, oldval);\
 310      else                                                             \
 311        __acev_wret                                                    \
 312          = __v7_compare_and_exchange_val_24_acq (mem, newval, oldval);\
 313      __acev_wret; })
 314
 315 # define atomic_exchange_24_rel(mem, newval) \
 316   ({                                                                  \
 317      __typeof (*mem) __acev_w24ret;                                   \
 318      if (sizeof (*mem) != 4)                                          \
 319        abort ();                                                      \
 320      if (__atomic_is_v9)                                              \
 321        __acev_w24ret = atomic_exchange_rel (mem, newval);             \
 322      else                                                             \
 323        __acev_w24ret = __v7_exchange_24_rel (mem, newval);            \
 324      __acev_w24ret; })
 325
 326 #endif
 327
 328 #endif  /* bits/atomic.h */