atomic.h

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     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								      \
       __asm __volatile (LOCK_PREFIX "addq %q2, %0; sets %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "ir" ((long) (value)), "m" (*mem));		      \
     __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)		      \
			 : "iq" (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								      \
       __asm __volatile (LOCK_PREFIX "addq %q2, %0; setz %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "ir" ((long) (value)), "m" (*mem));		      \
     __result; })


#define __arch_increment_body(lock, mem) \
  do {									      \
    if (sizeof (*mem) == 1)						      \
      __asm __volatile (lock "incb %b0"					      \
			: "=m" (*mem)					      \
			: "m" (*mem),					      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
    else if (sizeof (*mem) == 2)					      \
      __asm __volatile (lock "incw %w0"					      \
			: "=m" (*mem)					      \
			: "m" (*mem),					      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
    else if (sizeof (*mem) == 4)					      \
      __asm __volatile (lock "incl %0"					      \
			: "=m" (*mem)					      \
			: "m" (*mem),					      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
    else								      \
      __asm __volatile (lock "incq %q0"					      \
			: "=m" (*mem)					      \
			: "m" (*mem),					      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
  } while (0)

#define atomic_increment(mem) __arch_increment_body (LOCK_PREFIX, mem)

#define __arch_increment_cprefix \
  "cmpl $0, %%fs:%P2\n\tje 0f\n\tlock\n0:\t"

#define catomic_increment(mem) \
  __arch_increment_body (__arch_increment_cprefix, mem)


#define atomic_increment_and_test(mem) \
  ({ unsigned char __result;						      \
     if (sizeof (*mem) == 1)						      \
       __asm __volatile (LOCK_PREFIX "incb %b0; sete %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "m" (*mem));					      \
     else if (sizeof (*mem) == 2)					      \
       __asm __volatile (LOCK_PREFIX "incw %w0; sete %1"		      \
			 : "=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								      \
       __asm __volatile (LOCK_PREFIX "incq %q0; sete %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "m" (*mem));					      \
     __result; })


#define __arch_decrement_body(lock, mem) \
  do {									      \
    if (sizeof (*mem) == 1)						      \
      __asm __volatile (lock "decb %b0"					      \
			: "=m" (*mem)					      \
			: "m" (*mem),					      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
    else if (sizeof (*mem) == 2)					      \
      __asm __volatile (lock "decw %w0"					      \
			: "=m" (*mem)					      \
			: "m" (*mem),					      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
    else if (sizeof (*mem) == 4)					      \
      __asm __volatile (lock "decl %0"					      \
			: "=m" (*mem)					      \
			: "m" (*mem),					      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
    else								      \
      __asm __volatile (lock "decq %q0"					      \
			: "=m" (*mem)					      \
			: "m" (*mem),					      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
  } while (0)

#define atomic_decrement(mem) __arch_decrement_body (LOCK_PREFIX, mem)

#define __arch_decrement_cprefix \
  "cmpl $0, %%fs:%P2\n\tje 0f\n\tlock\n0:\t"

#define catomic_decrement(mem) \
  __arch_decrement_body (__arch_decrement_cprefix, mem)


#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								      \
       __asm __volatile (LOCK_PREFIX "decq %q0; sete %1"		      \
			 : "=m" (*mem), "=qm" (__result)		      \
			 : "m" (*mem));					      \
     __result; })


#define atomic_bit_set(mem, bit) \
  do {									      \
    if (sizeof (*mem) == 1)						      \
      __asm __volatile (LOCK_PREFIX "orb %b2, %0"			      \
			: "=m" (*mem)					      \
			: "m" (*mem), "iq" (1L << (bit)));		      \
    else if (sizeof (*mem) == 2)					      \
      __asm __volatile (LOCK_PREFIX "orw %w2, %0"			      \
			: "=m" (*mem)					      \
			: "m" (*mem), "ir" (1L << (bit)));		      \
    else if (sizeof (*mem) == 4)					      \
      __asm __volatile (LOCK_PREFIX "orl %2, %0"			      \
			: "=m" (*mem)					      \
			: "m" (*mem), "ir" (1L << (bit)));		      \
    else if (__builtin_constant_p (bit) && (bit) < 32)			      \
      __asm __volatile (LOCK_PREFIX "orq %2, %0"			      \
			: "=m" (*mem)					      \
			: "m" (*mem), "i" (1L << (bit)));		      \
    else								      \
      __asm __volatile (LOCK_PREFIX "orq %q2, %0"			      \
			: "=m" (*mem)					      \
			: "m" (*mem), "r" (1UL << (bit)));		      \
  } while (0)


#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), "iq" (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							      	      \
       __asm __volatile (LOCK_PREFIX "btsq %3, %1; setc %0"		      \
			 : "=q" (__result), "=m" (*mem)			      \
			 : "m" (*mem), "ir" (bit));			      \
     __result; })


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


#define atomic_and(mem, mask) \
  do {									      \
    if (sizeof (*mem) == 1)						      \
      __asm __volatile (LOCK_PREFIX "andb %b1, %0"			      \
			: "=m" (*mem)					      \
			: "iq" (mask), "m" (*mem));			      \
    else if (sizeof (*mem) == 2)					      \
      __asm __volatile (LOCK_PREFIX "andw %w1, %0"			      \
			: "=m" (*mem)					      \
			: "ir" (mask), "m" (*mem));			      \
    else if (sizeof (*mem) == 4)					      \
      __asm __volatile (LOCK_PREFIX "andl %1, %0"			      \
			: "=m" (*mem)					      \
			: "ir" (mask), "m" (*mem));			      \
    else								      \
      __asm __volatile (LOCK_PREFIX "andq %q1, %0"			      \
			: "=m" (*mem)					      \
			: "ir" (mask), "m" (*mem));			      \
  } while (0)


#define __arch_or_body(lock, mem, mask)					      \
  do {									      \
    if (sizeof (*mem) == 1)						      \
      __asm __volatile (lock "orb %b1, %0"				      \
			: "=m" (*mem)					      \
			: "iq" (mask), "m" (*mem),			      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
    else if (sizeof (*mem) == 2)					      \
      __asm __volatile (lock "orw %w1, %0"				      \
			: "=m" (*mem)					      \
			: "ir" (mask), "m" (*mem),			      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
    else if (sizeof (*mem) == 4)					      \
      __asm __volatile (lock "orl %1, %0"				      \
			: "=m" (*mem)					      \
			: "ir" (mask), "m" (*mem),			      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
    else								      \
      __asm __volatile (lock "orq %q1, %0"				      \
			: "=m" (*mem)					      \
			: "ir" (mask), "m" (*mem),			      \
			  "i" (offsetof (tcbhead_t, multiple_threads)));      \
  } while (0)

#define atomic_or(mem, mask) __arch_or_body (LOCK_PREFIX, mem, mask)

#define __arch_or_cprefix \
  "cmpl $0, %%fs:%P3\n\tje 0f\n\tlock\n0:\t"

#define catomic_or(mem, mask) __arch_or_body (__arch_or_cprefix, mem, mask)