Commit e88edf6a authored by davi@mysql.com/endora.local's avatar davi@mysql.com/endora.local
Browse files

Bug#33728 Atomic builtins 

Use compiler provided atomic builtins as a 'backend' for
MySQL's atomic primitives. The builtins are available on
a handful of platforms and compilers.
parent 3cd3a40d

configure.in

+24 −0
Original line number Diff line number Diff line
@@ -1688,6 +1688,30 @@ case "$with_atomic_ops" in 
   *) AC_MSG_ERROR(["$with_atomic_ops" is not a valid value for --with-atomic-ops]) ;;

esac



AC_CACHE_CHECK([whether the compiler provides atomic builtins],

               [mysql_cv_gcc_atomic_builtins], [AC_TRY_RUN([

  int main()

  {

    int foo= -10; int bar= 10;

    if (!__sync_fetch_and_add(&foo, bar) || foo)

      return -1;

    bar= __sync_lock_test_and_set(&foo, bar);

    if (bar || foo != 10)

      return -1;

    bar= __sync_val_compare_and_swap(&bar, foo, 15);

    if (bar)

      return -1;

    return 0;

  }

], [mysql_cv_gcc_atomic_builtins=yes],

   [mysql_cv_gcc_atomic_builtins=no],

   [mysql_cv_gcc_atomic_builtins=no])])



if test "x$mysql_cv_gcc_atomic_builtins" = xyes; then

  AC_DEFINE(HAVE_GCC_ATOMIC_BUILTINS, 1,

            [Define to 1 if compiler provides atomic builtins.])

fi



# Force static compilation to avoid linking problems/get more speed

AC_ARG_WITH(mysqld-ldflags,

    [  --with-mysqld-ldflags   Extra linking arguments for mysqld],

include/atomic/gcc_builtins.h

0 → 100644
+33 −0
Original line number Diff line number Diff line 
/* Copyright (C) 2008 MySQL AB



   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; version 2 of the License.



   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.



   You should have received a copy of the GNU General Public License

   along with this program; if not, write to the Free Software

   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */



#define make_atomic_add_body(S)                     \

  v= __sync_fetch_and_add(a, v);

#define make_atomic_swap_body(S)                    \

  v= __sync_lock_test_and_set(a, v);

#define make_atomic_cas_body(S)                     \

  int ## S sav;                                     \

  sav= __sync_val_compare_and_swap(a, *cmp, set);   \

  if (!(ret= (sav == *cmp))) *cmp= sav;



#ifdef MY_ATOMIC_MODE_DUMMY

#define make_atomic_load_body(S)   ret= *a

#define make_atomic_store_body(S)  *a= v

#else

#define make_atomic_load_body(S)                    \

  ret= __sync_fetch_and_or(a, 0);

#define make_atomic_store_body(S)                   \

  (void) __sync_lock_test_and_set(a, v);

#endif

include/atomic/nolock.h

+4 −2
Original line number Diff line number Diff line
@@ -13,7 +13,7 @@ 
   along with this program; if not, write to the Free Software

   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */



#if defined(__i386__) || defined(_M_IX86)

#if defined(__i386__) || defined(_M_IX86) || defined(HAVE_GCC_ATOMIC_BUILTINS)



#ifdef MY_ATOMIC_MODE_DUMMY

#  define LOCK ""
@@ -21,7 +21,9 @@ 
#  define LOCK "lock"

#endif



#ifdef __GNUC__

#ifdef HAVE_GCC_ATOMIC_BUILTINS

#include "gcc_builtins.h"

#elif __GNUC__

#include "x86-gcc.h"

#elif defined(_MSC_VER)

#include "x86-msvc.h"