/* GLIB - Library of useful routines for C programming

 * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald

 *

 * g_atomic_*: atomic operations.

 * Copyright (C) 2003 Sebastian Wilhelmi

 * Portions copyright (c) 2006 Nokia Corporation.  All rights reserved.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

 * Boston, MA 02111-1307, USA.

 */

#include "config.h"

#include "glib.h"

#include "gthreadinit.h"

#include "galias.h"

#ifdef __SYMBIAN32__

#include <glib_wsd.h>

#endif /* __SYMBIAN32__ */

#if EMULATOR

#define g_thread_functions_for_glib_use (*_g_thread_functions_for_glib_use())

#define g_thread_use_default_impl (*_g_thread_use_default_impl())

#endif /* EMULATOR */

#if defined (__GNUC__)

#define GCC_VERSION (__GNUC__ * 10000 \

                               + __GNUC_MINOR__ * 100 \

                               + __GNUC_PATCHLEVEL__)

/* Test for GCC > 4.4.0 */

# if (GCC_VERSION > 40400)

EXPORT_C gint

g_atomic_int_exchange_and_add (volatile gint *atomic,

			       gint           val)

{

   return __sync_fetch_and_add(atomic, val);

}

EXPORT_C void

g_atomic_int_add (volatile gint *atomic,

		  gint           val)

{

   __sync_fetch_and_add(atomic, val);

}

EXPORT_C gboolean

g_atomic_int_compare_and_exchange (volatile gint *atomic,

				   gint           oldval,

				   gint           newval)

{

  return __sync_val_compare_and_swap(atomic, oldval, newval);

}

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic,

				       gpointer           oldval,

				       gpointer           newval)

{

  return __sync_val_compare_and_swap(atomic, oldval, newval);

}

#elif defined (G_ATOMIC_I486)

/* Adapted from CVS version 1.10 of glibc's sysdeps/i386/i486/bits/atomic.h 

 */

EXPORT_C gint

g_atomic_int_exchange_and_add (volatile gint *atomic, 

			       gint           val)

{

  gint result;

  __asm__ __volatile__ ("lock; xaddl %0,%1"

                        : "=r" (result), "=m" (*atomic) 

			: "0" (val), "m" (*atomic));

  return result;

}

EXPORT_C void

g_atomic_int_add (volatile gint *atomic, 

		  gint           val)

{

  __asm__ __volatile__ ("lock; addl %1,%0"

			: "=m" (*atomic) 

			: "ir" (val), "m" (*atomic));

}

EXPORT_C gboolean

g_atomic_int_compare_and_exchange (volatile gint *atomic, 

				   gint           oldval, 

				   gint           newval)

{

  gint result;

  __asm__ __volatile__ ("lock; cmpxchgl %2, %1"

			: "=a" (result), "=m" (*atomic)

			: "r" (newval), "m" (*atomic), "0" (oldval)); 

  return result == oldval;

}

/* The same code as above, as on i386 gpointer is 32 bit as well.

 * Duplicating the code here seems more natural than casting the

 * arguments and calling the former function */

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic, 

				       gpointer           oldval, 

				       gpointer           newval)

{

  gpointer result;

  __asm__ __volatile__ ("lock; cmpxchgl %2, %1"

			: "=a" (result), "=m" (*atomic)

			: "r" (newval), "m" (*atomic), "0" (oldval)); 

  return result == oldval;

}

# elif defined (G_ATOMIC_SPARCV9)

/* Adapted from CVS version 1.3 of glibc's sysdeps/sparc/sparc64/bits/atomic.h

 */

#  define ATOMIC_INT_CMP_XCHG(atomic, oldval, newval)			\

  ({ 									\

     gint __result;							\

     __asm__ __volatile__ ("cas [%4], %2, %0"				\

                           : "=r" (__result), "=m" (*(atomic))		\

                           : "r" (oldval), "m" (*(atomic)), "r" (atomic),\

                           "0" (newval));				\

     __result == oldval;						\

  })

#  if GLIB_SIZEOF_VOID_P == 4 /* 32-bit system */

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic, 

				       gpointer           oldval, 

				       gpointer           newval)

{

  gpointer result;

  __asm__ __volatile__ ("cas [%4], %2, %0"

			: "=r" (result), "=m" (*atomic)

			: "r" (oldval), "m" (*atomic), "r" (atomic),

			"0" (newval));

  return result == oldval;

}

#  elif GLIB_SIZEOF_VOID_P == 8 /* 64-bit system */

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic, 

				       gpointer           oldval, 

				       gpointer           newval)

{

  gpointer result;

  gpointer *a = atomic;

  __asm__ __volatile__ ("casx [%4], %2, %0"

			: "=r" (result), "=m" (*a)

			: "r" (oldval), "m" (*a), "r" (a),

			"0" (newval));

  return result == oldval;

}

#  else /* What's that */

#    error "Your system has an unsupported pointer size"

#  endif /* GLIB_SIZEOF_VOID_P */

#  define G_ATOMIC_MEMORY_BARRIER					\

  __asm__ __volatile__ ("membar #LoadLoad | #LoadStore"			\

                        " | #StoreLoad | #StoreStore" : : : "memory")

# elif defined (G_ATOMIC_ALPHA)

/* Adapted from CVS version 1.3 of glibc's sysdeps/alpha/bits/atomic.h

 */

#  define ATOMIC_INT_CMP_XCHG(atomic, oldval, newval)			\

  ({ 									\

     gint __result;							\

     gint __prev;							\

     __asm__ __volatile__ (						\

        "       mb\n"							\

        "1:     ldl_l   %0,%2\n"					\

        "       cmpeq   %0,%3,%1\n"					\

        "       beq     %1,2f\n"					\

        "       mov     %4,%1\n"					\

        "       stl_c   %1,%2\n"					\

        "       beq     %1,1b\n"					\

        "       mb\n"							\

        "2:"								\

        : "=&r" (__prev), 						\

          "=&r" (__result)						\

        : "m" (*(atomic)),						\

          "Ir" (oldval),						\

          "Ir" (newval)							\

        : "memory");							\

     __result != 0;							\

  })

#  if GLIB_SIZEOF_VOID_P == 4 /* 32-bit system */

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic, 

				       gpointer           oldval, 

				       gpointer           newval)

{

  gint result;

  gpointer prev;

  __asm__ __volatile__ (

        "       mb\n"

        "1:     ldl_l   %0,%2\n"

        "       cmpeq   %0,%3,%1\n"

        "       beq     %1,2f\n"

        "       mov     %4,%1\n"

        "       stl_c   %1,%2\n"

        "       beq     %1,1b\n"

        "       mb\n"

        "2:"

        : "=&r" (prev), 

          "=&r" (result)

        : "m" (*atomic),

          "Ir" (oldval),

          "Ir" (newval)

        : "memory");

  return result != 0;

}

#  elif GLIB_SIZEOF_VOID_P == 8 /* 64-bit system */

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic, 

				       gpointer           oldval, 

				       gpointer           newval)

{

  gint result;

  gpointer prev;

  __asm__ __volatile__ (

        "       mb\n"

        "1:     ldq_l   %0,%2\n"

        "       cmpeq   %0,%3,%1\n"

        "       beq     %1,2f\n"

        "       mov     %4,%1\n"

        "       stq_c   %1,%2\n"

        "       beq     %1,1b\n"

        "       mb\n"

        "2:"

        : "=&r" (prev), 

          "=&r" (result)

        : "m" (*atomic),

          "Ir" (oldval),

          "Ir" (newval)

        : "memory");

  return result != 0;

}

#  else /* What's that */

#   error "Your system has an unsupported pointer size"

#  endif /* GLIB_SIZEOF_VOID_P */

#  define G_ATOMIC_MEMORY_BARRIER  __asm__ ("mb" : : : "memory")

# elif defined (G_ATOMIC_X86_64)

/* Adapted from CVS version 1.9 of glibc's sysdeps/x86_64/bits/atomic.h 

 */

EXPORT_C gint

g_atomic_int_exchange_and_add (volatile gint *atomic,

			       gint           val)

{

  gint result;

  __asm__ __volatile__ ("lock; xaddl %0,%1"

                        : "=r" (result), "=m" (*atomic) 

			: "0" (val), "m" (*atomic));

  return result;

}

EXPORT_C void

g_atomic_int_add (volatile gint *atomic, 

		  gint           val)

{

  __asm__ __volatile__ ("lock; addl %1,%0"

			: "=m" (*atomic) 

			: "ir" (val), "m" (*atomic));

}

EXPORT_C gboolean

g_atomic_int_compare_and_exchange (volatile gint *atomic, 

				   gint           oldval, 

				   gint           newval)

{

  gint result;

  __asm__ __volatile__ ("lock; cmpxchgl %2, %1"

			: "=a" (result), "=m" (*atomic)

			: "r" (newval), "m" (*atomic), "0" (oldval)); 

  return result == oldval;

}

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic, 

				       gpointer           oldval, 

				       gpointer           newval)

{

  gpointer result;

  __asm__ __volatile__ ("lock; cmpxchgq %q2, %1"

			: "=a" (result), "=m" (*atomic)

			: "r" (newval), "m" (*atomic), "0" (oldval)); 

  return result == oldval;

}

# elif defined (G_ATOMIC_POWERPC)

/* Adapted from CVS version 1.16 of glibc's sysdeps/powerpc/bits/atomic.h 

 * and CVS version 1.4 of glibc's sysdeps/powerpc/powerpc32/bits/atomic.h 

 * and CVS version 1.7 of glibc's sysdeps/powerpc/powerpc64/bits/atomic.h 

 */

#   ifdef __OPTIMIZE__

/* Non-optimizing compile bails on the following two asm statements

 * for reasons unknown to the author */

EXPORT_C gint

g_atomic_int_exchange_and_add (volatile gint *atomic, 

			       gint           val)

{

  gint result, temp;

  __asm__ __volatile__ ("1:       lwarx   %0,0,%3\n"

			"         add     %1,%0,%4\n"

			"         stwcx.  %1,0,%3\n"

			"         bne-    1b"

			: "=&b" (result), "=&r" (temp), "=m" (*atomic)

			: "b" (atomic), "r" (val), "m" (*atomic)

			: "cr0", "memory");

  return result;

}

/* The same as above, to save a function call repeated here */

EXPORT_C void

g_atomic_int_add (volatile gint *atomic, 

		  gint           val)

{

  gint result, temp;  

  __asm__ __volatile__ ("1:       lwarx   %0,0,%3\n"

			"         add     %1,%0,%4\n"

			"         stwcx.  %1,0,%3\n"

			"         bne-    1b"

			: "=&b" (result), "=&r" (temp), "=m" (*atomic)

			: "b" (atomic), "r" (val), "m" (*atomic)

			: "cr0", "memory");

}

#   else /* !__OPTIMIZE__ */

EXPORT_C gint

g_atomic_int_exchange_and_add (volatile gint *atomic, 

			       gint           val)

{

  gint result;

  do

    result = *atomic;

  while (!g_atomic_int_compare_and_exchange (atomic, result, result + val));

  return result;

}

EXPORT_C void

g_atomic_int_add (volatile gint *atomic,

		  gint           val)

{

  gint result;

  do

    result = *atomic;

  while (!g_atomic_int_compare_and_exchange (atomic, result, result + val));

}

#   endif /* !__OPTIMIZE__ */

#   if GLIB_SIZEOF_VOID_P == 4 /* 32-bit system */

EXPORT_C gboolean

g_atomic_int_compare_and_exchange (volatile gint *atomic, 

				   gint           oldval, 

				   gint           newval)

{

  gint result;

  __asm__ __volatile__ ("sync\n"

			"1: lwarx   %0,0,%1\n"

			"   subf.   %0,%2,%0\n"

			"   bne     2f\n"

			"   stwcx.  %3,0,%1\n"

			"   bne-    1b\n"

			"2: isync"

			: "=&r" (result)

			: "b" (atomic), "r" (oldval), "r" (newval)

			: "cr0", "memory"); 

  return result == 0;

}

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic, 

				       gpointer           oldval, 

				       gpointer           newval)

{

  gpointer result;

  __asm__ __volatile__ ("sync\n"

			"1: lwarx   %0,0,%1\n"

			"   subf.   %0,%2,%0\n"

			"   bne     2f\n"

			"   stwcx.  %3,0,%1\n"

			"   bne-    1b\n"

			"2: isync"

			: "=&r" (result)

			: "b" (atomic), "r" (oldval), "r" (newval)

			: "cr0", "memory"); 

  return result == 0;

}

#   elif GLIB_SIZEOF_VOID_P == 8 /* 64-bit system */

EXPORT_C gboolean

g_atomic_int_compare_and_exchange (volatile gint *atomic,

				   gint           oldval, 

				   gint           newval)

{

  gpointer result;

  __asm__ __volatile__ ("sync\n"

			"1: lwarx   %0,0,%1\n"

			"   extsw   %0,%0\n"

			"   subf.   %0,%2,%0\n"

			"   bne     2f\n"

			"   stwcx.  %3,0,%1\n"

			"   bne-    1b\n"

			"2: isync"

			: "=&r" (result)

			: "b" (atomic), "r" (oldval), "r" (newval)

			: "cr0", "memory"); 

  return result == 0;

}

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic, 

				       gpointer           oldval, 

				       gpointer           newval)

{

  gpointer result;

  __asm__ __volatile__ ("sync\n"

			"1: ldarx   %0,0,%1\n"

			"   subf.   %0,%2,%0\n"

			"   bne     2f\n"

			"   stdcx.  %3,0,%1\n"

			"   bne-    1b\n"

			"2: isync"

			: "=&r" (result)

			: "b" (atomic), "r" (oldval), "r" (newval)

			: "cr0", "memory"); 

  return result == 0;

}

#  else /* What's that */

#   error "Your system has an unsupported pointer size"

#  endif /* GLIB_SIZEOF_VOID_P */

#  define G_ATOMIC_MEMORY_BARRIER __asm__ ("sync" : : : "memory")

# elif defined (G_ATOMIC_IA64)

/* Adapted from CVS version 1.8 of glibc's sysdeps/ia64/bits/atomic.h

 */

EXPORT_C gint

g_atomic_int_exchange_and_add (volatile gint *atomic,

			       gint           val)

{

  return __sync_fetch_and_add (atomic, val);

}

EXPORT_C void

g_atomic_int_add (volatile gint *atomic, 

		  gint val)

{

  __sync_fetch_and_add (atomic, val);

}

EXPORT_C gboolean

g_atomic_int_compare_and_exchange (volatile gint *atomic,

				   gint           oldval, 

				   gint           newval)

{

  return __sync_bool_compare_and_swap (atomic, oldval, newval);

}

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic,

				       gpointer           oldval, 

				       gpointer           newval)

{

  return __sync_bool_compare_and_swap ((long *)atomic, 

				       (long)oldval, (long)newval);

}

#  define G_ATOMIC_MEMORY_BARRIER __sync_synchronize ()

# elif defined (G_ATOMIC_S390)

/* Adapted from glibc's sysdeps/s390/bits/atomic.h

 */

#  define ATOMIC_INT_CMP_XCHG(atomic, oldval, newval)			\

  ({ 									\

     gint __result = oldval;					\

     __asm__ __volatile__ ("cs %0, %2, %1"				\

                           : "+d" (__result), "=Q" (*(atomic))		\

                           : "d" (newval), "m" (*(atomic)) : "cc" );	\

     __result == oldval;						\

  })

#  if GLIB_SIZEOF_VOID_P == 4 /* 32-bit system */

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic,

				       gpointer           oldval,

				       gpointer           newval)

{

  gpointer result = oldval;

  __asm__ __volatile__ ("cs %0, %2, %1"

			: "+d" (result), "=Q" (*(atomic))

			: "d" (newval), "m" (*(atomic)) : "cc" );

  return result == oldval;

}

#  elif GLIB_SIZEOF_VOID_P == 8 /* 64-bit system */

EXPORT_C gboolean

g_atomic_pointer_compare_and_exchange (volatile gpointer *atomic,

				       gpointer           oldval,

				       gpointer           newval)

{

  gpointer result = oldval;

  gpointer *a = atomic;

  __asm__ __volatile__ ("csg %0, %2, %1"

			: "+d" (result), "=Q" (*a)