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/* Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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>
#include <sysdep.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 int32_t atomic32_t;
typedef uint32_t uatomic32_t;
typedef int_fast32_t atomic_fast32_t;
typedef uint_fast32_t uatomic_fast32_t;
typedef intptr_t atomicptr_t;
typedef uintptr_t uatomicptr_t;
typedef intmax_t atomic_max_t;
typedef uintmax_t uatomic_max_t;
void __arm_link_error (void);
#ifdef __thumb__
/* Note that to allow efficient implementation the arguemtns are reversed
relative to atomic_exchange_acq. */
int __thumb_swpb (int newvalue, void *mem)
attribute_hidden;
unsigned int __thumb_swp (unsigned int newvalue, void *mem)
attribute_hidden;
unsigned int __thumb_cmpxchg (unsigned int oldval, unsigned int newval, void *mem)
attribute_hidden;
#define atomic_exchange_acq(mem, newvalue) \
({ __typeof (*mem) result; \
if (sizeof (*mem) == 1) \
result = __thumb_swpb (newvalue, mem); \
else if (sizeof (*mem) == 4) \
result = __thumb_swp (newvalue, mem); \
else \
{ \
result = 0; \
abort (); \
} \
result; })
#define __arch_compare_and_exchange_val_8_acq(mem, newval, oldval) \
({ __arm_link_error (); oldval; })
#define __arch_compare_and_exchange_val_16_acq(mem, newval, oldval) \
({ __arm_link_error (); oldval; })
#define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \
((__typeof (oldval)) __thumb_cmpxchg (oldval, newval, mem))
#define __arch_compare_and_exchange_val_64_acq(mem, newval, oldval) \
({ __arm_link_error (); oldval; })
#else
/* ARM mode. */
#define atomic_exchange_acq(mem, newvalue) \
({ __typeof (*mem) _xchg_result; \
if (sizeof (*mem) == 1) \
__asm__ __volatile__ ("swpb %0, %1, [%2]" \
: "=&r,&r" (_xchg_result) \
: "r,0" (newvalue), "r,r" (mem) : "memory"); \
else if (sizeof (*mem) == 4) \
__asm__ __volatile__ ("swp %0, %1, [%2]" \
: "=&r,&r" (_xchg_result) \
: "r,0" (newvalue), "r,r" (mem) : "memory"); \
else \
{ \
_xchg_result = 0; \
abort (); \
} \
_xchg_result; })
/* Atomic compare and exchange. This sequence relies on the kernel to
provide a compare and exchange operation which is atomic on the
current architecture, either via cleverness on pre-ARMv6 or via
ldrex / strex on ARMv6. */
#define __arch_compare_and_exchange_val_8_acq(mem, newval, oldval) \
({ __arm_link_error (); oldval; })
#define __arch_compare_and_exchange_val_16_acq(mem, newval, oldval) \
({ __arm_link_error (); oldval; })
/* It doesn't matter what register is used for a_oldval2, but we must
specify one to work around GCC PR rtl-optimization/21223. Otherwise
it may cause a_oldval or a_tmp to be moved to a different register. */
#define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \
({ register __typeof (oldval) a_oldval asm ("r0"); \
register __typeof (oldval) a_newval asm ("r1") = (newval); \
register __typeof (mem) a_ptr asm ("r2") = (mem); \
register __typeof (oldval) a_tmp asm ("r3"); \
register __typeof (oldval) a_oldval2 asm ("r4") = (oldval); \
__asm__ __volatile__ \
("0:\tldr\t%1,[%3]\n\t" \
"cmp\t%1, %4\n\t" \
"bne\t1f\n\t" \
"mov\t%0, %4\n\t" \
"mov\t%1, #0xffff0fff\n\t" \
"mov\tlr, pc\n\t" \
"add\tpc, %1, #(0xffff0fc0 - 0xffff0fff)\n\t" \
"bcc\t0b\n\t" \
"mov\t%1, %4\n\t" \
"1:" \
: "=&r" (a_oldval), "=&r" (a_tmp) \
: "r" (a_newval), "r" (a_ptr), "r" (a_oldval2) \
: "ip", "lr", "cc", "memory"); \
a_tmp; })
#define __arch_compare_and_exchange_val_64_acq(mem, newval, oldval) \
({ __arm_link_error (); oldval; })
#endif /* __thumb__ */
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