/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.

   The GNU C 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 2.1 of the License, or (at your option) any later version.

   The GNU C 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 the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <stdint.h>


typedef int8_t atomic8_t;
typedef uint8_t uatomic8_t;
typedef int_fast8_t atomic_fast8_t;
typedef uint_fast8_t uatomic_fast8_t;

typedef int16_t atomic16_t;
typedef uint16_t uatomic16_t;
typedef int_fast16_t atomic_fast16_t;
typedef uint_fast16_t uatomic_fast16_t;

typedef int32_t atomic32_t;
typedef uint32_t uatomic32_t;
typedef int_fast32_t atomic_fast32_t;
typedef uint_fast32_t uatomic_fast32_t;

typedef int64_t atomic64_t;
typedef uint64_t uatomic64_t;
typedef int_fast64_t atomic_fast64_t;
typedef uint_fast64_t uatomic_fast64_t;

typedef intptr_t atomicptr_t;
typedef uintptr_t uatomicptr_t;
typedef intmax_t atomic_max_t;
typedef uintmax_t uatomic_max_t;


#ifndef LOCK_PREFIX
# ifdef UP
#  define LOCK_PREFIX	/* nothing */
# else
#  define LOCK_PREFIX "lock;"
# endif
#endif

/* i386 doesn't have cmpxchg* and xadd*.  Instead of being completely
   non-atomic, atomic_* macros that are using solely i386 instructions
   are using those atomic instructions and the remaining ones are
   non-atomic.  When in nscd, use i486+ instructions if on i486+.  */

#ifdef IS_IN_nscd

extern int has_cmpxchg attribute_hidden;

#define atomic_supports_shared has_cmpxchg

#define atomic_init_nscd \
int has_cmpxchg attribute_hidden;					      \
static void __attribute__((constructor))				      \
init_has_cmpxchg (void)							      \
{									      \
  int fl1, fl2;								      \
  __asm__ ("pushfl; pushfl; popl %0; movl %0,%1; xorl %2,%0;"		      \
	   "pushl %0; popfl; pushfl; popl %0; popfl"			      \
	   : "=&r" (fl1), "=&r" (fl2) : "i" (0x00040000));		      \
  if ((fl1 ^ fl2) & 0x00040000)						      \
    has_cmpxchg = 1;							      \
}

# define __arch_compare_and_exchange_val_8_acq(mem, newval, oldval) \
  ({ __typeof (*mem) ret;						      \
     if (__builtin_expect (has_cmpxchg, 1))				      \
       __asm __volatile (LOCK_PREFIX "cmpxchgb %b2, %1"			      \
			 : "=a" (ret), "=m" (*mem)			      \
			 : "q" (newval), "m" (*mem), "0" (oldval));	      \
     else								      \
       {								      \
	 ret = *mem;							      \
	 if (ret == oldval)						      \
	   *mem = (newval);						      \
       }								      \
     ret; })

# define __arch_compare_and_exchange_val_16_acq(mem, newval, oldval) \
  ({ __typeof (*mem) ret;						      \
     if (__builtin_expect (has_cmpxchg, 1))				      \
       __asm __volatile (LOCK_PREFIX "cmpxchgw %w2, %1"			      \
			 : "=a" (ret), "=m" (*mem)			      \
			 : "r" (newval), "m" (*mem), "0" (oldval));	      \
     else								      \
       {								      \
	 ret = *mem;							      \
	 if (ret == oldval)						      \
	   *mem = (newval);						      \
       }								      \
     ret; })

# define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \
  ({ __typeof (*mem) ret;						      \
     if (__builtin_expect (has_cmpxchg, 1))				      \
       __asm __volatile (LOCK_PREFIX "cmpxchgl %2, %1"			      \
			 : "=a" (ret), "=m" (*mem)			      \
			 : "r" (newval), "m" (*mem), "0" (oldval));	      \
     else								      \
       {								      \
	 ret = *mem;							      \
	 if (ret == oldval)						      \
	   *mem = (newval);						      \
       }								      \
     ret; })

/* XXX We do not really need 64-bit compare-and-exchange.  At least
   not in the moment.  */
# define __arch_compare_and_exchange_val_64_acq(mem, newval, oldval) \
  ({ __typeof (*mem) ret = *(mem); abort (); ret = (newval); ret = (oldval); })


# define atomic_exchange_and_add(mem, value) \
  ({ __typeof (*mem) __result;						      \
     __typeof (value) __addval = (value);				      \
     if (__builtin_expect (! has_cmpxchg, 0))				      \
       {								      \
	 __typeof (mem) __memp = (mem);					      \
	 __result = *__memp;						      \
	 *__memp += __addval;						      \
       }								      \
     else if (sizeof (*mem) == 1)					      \
       __asm __volatile (LOCK_PREFIX "xaddb %b0, %1"			      \
			 : "=r" (__result), "=m" (*mem)			      \
			 : "0" (__addval), "m" (*mem));			      \
     else if (sizeof (*mem) == 2)					      \
       __asm __volatile (LOCK_PREFIX "xaddw %w0, %1"			      \
			 : "=r" (__result), "=m" (*mem)			      \
			 : "0" (__addval), "m" (*mem));			      \
     else if (sizeof (*mem) == 4)					      \
       __asm __volatile (LOCK_PREFIX "xaddl %0, %1"			      \
			 : "=r" (__result), "=m" (*mem)			      \
			 : "0" (__addval), "m" (*mem));			      \
     else								      \
       {								      \
	 __typeof (mem) __memp = (mem);					      \
	 __typeof (*mem) __tmpval;					      \
	 __result = *__memp;						      \
	 do								      \
	   __tmpval = __result;						      \
	 while ((__result = __arch_compare_and_exchange_val_64_acq	      \
		 (__memp, __result + __addval, __result)) == __tmpval);	      \
       }								      \
     __result; })

#else

/* We have by default no support for atomic operations.  So define
   them non-atomic.  If this is a problem somebody will have to come
   up with real definitions.  */

/* The only basic operation needed is compare and exchange.  */
#define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \
  ({ __typeof (mem) __gmemp = (mem);					      \
     __typeof (*mem) __gret = *__gmemp;					      \
     __typeof (*mem) __gnewval = (newval);				      \
									      \
     if (__gret == (oldval))						      \
       *__gmemp = __gnewval;						      \
     __gret; })

#define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
  ({ __typeof (mem) __gmemp = (mem);					      \
     __typeof (*mem) __gnewval = (newval);				      \
									      \
     *__gmemp == (oldval) ? (*__gmemp = __gnewval, 0) : 1; })

#endif

/* Note that we need no lock prefix.  */
#define atomic_exchange_acq(mem, newvalue) \
  ({ __typeof (*mem) result;						      \
     if (sizeof (*mem) == 1)						      \
       __asm __volatile ("xchgb %b0, %1"				      \
			 : "=r" (result), "=m" (*mem)			      \
			 : "0" (newvalue), "m" (*mem));			      \
     else if (sizeof (*mem) == 2)					      \
       __asm __volatile ("xchgw %w0, %1"				      \
			 : "=r" (result), "=m" (*mem)			      \
			 : "0" (newvalue), "m" (*mem));			      \
     else if (sizeof (*mem) == 4)					      \
       __asm __volatile ("xchgl %0, %1"					      \
			 : "=r" (result), "=m" (*mem)			      \
			 : "0" (newvalue), "m" (*mem));			      \
     else								      \
       {								      \
	 result = 0;							      \
	 abort ();							      \
       }								      \
     result; })


#define atomic_add(mem, value) \
  (void) ({ if (__builtin_constant_p (value) && (value) == 1)		      \
	      atomic_increment (mem);					      \
	    else if (__builtin_constant_p (value) && (value) == -1)	      \
	      atomic_decrement (mem);					      \
	    else if (sizeof (*mem) == 1)				      \
	      __asm __volatile (LOCK_PREFIX "addb %b1, %0"		      \
				: "=m" (*mem)				      \
				: "ir" (value), "m" (*mem));		      \
	    else if (sizeof (*mem) == 2)				      \
	      __asm __volatile (LOCK_PREFIX "addw %w1, %0"		      \
				: "=m" (*mem)				      \
				: "ir" (value), "m" (*mem));		      \
	    else if (sizeof (*mem) == 4)				      \
	      __asm __volatile (LOCK_PREFIX "addl %1, %0"		      \
				: "=m" (*mem)				      \
				: "ir" (value), "m" (*mem));		      \
	    else							      \
	      {								      \
		__typeof (value) __addval = (value);			      \
		__typeof (mem) __memp = (mem);				      \
		__typeof (*mem) __oldval = *__memp;			      \
		__typeof (*mem) __tmpval;				      \
		do							      \
		  __tmpval = __oldval;					      \
		while ((__oldval = __arch_compare_and_exchange_val_64_acq     \
		       (__memp, __oldval + __addval, __oldval)) == __tmpval); \
	      }								      \
	    })


#define atomic_add_negative(mem, value) \
  ({ unsigned char __result;						      \
     if (sizeof (*mem) == 1)						      \
       __asm __volatile (LOCK_PREFIX "addb %b2, %0; sets %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "iq" (value), "m" (*mem));			      \
     else if (sizeof (*mem) == 2)					      \
       __asm __volatile (LOCK_PREFIX "addw %w2, %0; sets %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "ir" (value), "m" (*mem));			      \
     else if (sizeof (*mem) == 4)					      \
       __asm __volatile (LOCK_PREFIX "addl %2, %0; sets %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "ir" (value), "m" (*mem));			      \
     else								      \
       abort ();							      \
     __result; })


#define atomic_add_zero(mem, value) \
  ({ unsigned char __result;						      \
     if (sizeof (*mem) == 1)						      \
       __asm __volatile (LOCK_PREFIX "addb %b2, %0; setz %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "ir" (value), "m" (*mem));			      \
     else if (sizeof (*mem) == 2)					      \
       __asm __volatile (LOCK_PREFIX "addw %w2, %0; setz %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "ir" (value), "m" (*mem));			      \
     else if (sizeof (*mem) == 4)					      \
       __asm __volatile (LOCK_PREFIX "addl %2, %0; setz %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "ir" (value), "m" (*mem));			      \
     else								      \
       abort ();							      \
     __result; })


#define atomic_increment(mem) \
  (void) ({ if (sizeof (*mem) == 1)					      \
	      __asm __volatile (LOCK_PREFIX "incb %b0"			      \
				: "=m" (*mem)				      \
				: "m" (*mem));				      \
	    else if (sizeof (*mem) == 2)				      \
	      __asm __volatile (LOCK_PREFIX "incw %w0"			      \
				: "=m" (*mem)				      \
				: "m" (*mem));				      \
	    else if (sizeof (*mem) == 4)				      \
	      __asm __volatile (LOCK_PREFIX "incl %0"			      \
				: "=m" (*mem)				      \
				: "m" (*mem));				      \
	    else							      \
	      {								      \
		__typeof (mem) __memp = (mem);				      \
		__typeof (*mem) __oldval = *__memp;			      \
		__typeof (*mem) __tmpval;				      \
		do							      \
		  __tmpval = __oldval;					      \
		while ((__oldval = __arch_compare_and_exchange_val_64_acq     \
		       (__memp, __oldval + 1, __oldval)) == __tmpval);	      \
	      }								      \
	    })


#define atomic_increment_and_test(mem) \
  ({ unsigned char __result;						      \
     if (sizeof (*mem) == 1)						      \
       __asm __volatile (LOCK_PREFIX "incb %0; sete %b1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "m" (*mem));					      \
     else if (sizeof (*mem) == 2)					      \
       __asm __volatile (LOCK_PREFIX "incw %0; sete %w1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "m" (*mem));					      \
     else if (sizeof (*mem) == 4)					      \
       __asm __volatile (LOCK_PREFIX "incl %0; sete %1"			      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "m" (*mem));					      \
     else								      \
       abort ();							      \
     __result; })


#define atomic_decrement(mem) \
  (void) ({ if (sizeof (*mem) == 1)					      \
	      __asm __volatile (LOCK_PREFIX "decb %b0"			      \
				: "=m" (*mem)				      \
				: "m" (*mem));				      \
	    else if (sizeof (*mem) == 2)				      \
	      __asm __volatile (LOCK_PREFIX "decw %w0"			      \
				: "=m" (*mem)				      \
				: "m" (*mem));				      \
	    else if (sizeof (*mem) == 4)				      \
	      __asm __volatile (LOCK_PREFIX "decl %0"			      \
				: "=m" (*mem)				      \
				: "m" (*mem));				      \
	    else							      \
	      {								      \
		__typeof (mem) __memp = (mem);				      \
		__typeof (*mem) __oldval = *__memp;			      \
		__typeof (*mem) __tmpval;				      \
		do							      \
		  __tmpval = __oldval;					      \
		while ((__oldval = __arch_compare_and_exchange_val_64_acq     \
		       (__memp, __oldval - 1, __oldval)) == __tmpval); 	      \
	      }								      \
	    })


#define atomic_decrement_and_test(mem) \
  ({ unsigned char __result;						      \
     if (sizeof (*mem) == 1)						      \
       __asm __volatile (LOCK_PREFIX "decb %b0; sete %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "m" (*mem));					      \
     else if (sizeof (*mem) == 2)					      \
       __asm __volatile (LOCK_PREFIX "decw %w0; sete %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "m" (*mem));					      \
     else if (sizeof (*mem) == 4)					      \
       __asm __volatile (LOCK_PREFIX "decl %0; sete %1"			      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "m" (*mem));					      \
     else								      \
       abort ();							      \
     __result; })


#define atomic_bit_set(mem, bit) \
  (void) ({ if (sizeof (*mem) == 1)					      \
	      __asm __volatile (LOCK_PREFIX "orb %b2, %0"		      \
				: "=m" (*mem)				      \
				: "m" (*mem), "ir" (1 << (bit)));	      \
	    else if (sizeof (*mem) == 2)				      \
	      __asm __volatile (LOCK_PREFIX "orw %w2, %0"		      \
				: "=m" (*mem)				      \
				: "m" (*mem), "ir" (1 << (bit)));	      \
	    else if (sizeof (*mem) == 4)				      \
	      __asm __volatile (LOCK_PREFIX "orl %2, %0"		      \
				: "=m" (*mem)				      \
				: "m" (*mem), "ir" (1 << (bit)));	      \
	    else							      \
	      abort ();							      \
	    })


#define atomic_bit_test_set(mem, bit) \
  ({ unsigned char __result;						      \
     if (sizeof (*mem) == 1)						      \
       __asm __volatile (LOCK_PREFIX "btsb %3, %1; setc %0"		      \
			 : "=q" (__result), "=m" (*mem)			      \
			 : "m" (*mem), "ir" (bit));			      \
     else if (sizeof (*mem) == 2)					      \
       __asm __volatile (LOCK_PREFIX "btsw %3, %1; setc %0"		      \
			 : "=q" (__result), "=m" (*mem)			      \
			 : "m" (*mem), "ir" (bit));			      \
     else if (sizeof (*mem) == 4)					      \
       __asm __volatile (LOCK_PREFIX "btsl %3, %1; setc %0"		      \
			 : "=q" (__result), "=m" (*mem)			      \
			 : "m" (*mem), "ir" (bit));			      \
     else							      	      \
       abort ();							      \
     __result; })


#define atomic_delay() asm ("rep; nop")