mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-02 09:40:13 +00:00
102 lines
3.7 KiB
C
102 lines
3.7 KiB
C
/* 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);
|
|
|
|
#define atomic_exchange_acq(mem, newvalue) \
|
|
({ __typeof (*mem) result; \
|
|
if (sizeof (*mem) == 1) \
|
|
__asm__ __volatile__ ("swpb %0, %1, [%2]" \
|
|
: "=&r,&r" (result) \
|
|
: "r,0" (newvalue), "r,r" (mem) : "memory"); \
|
|
else if (sizeof (*mem) == 4) \
|
|
__asm__ __volatile__ ("swp %0, %1, [%2]" \
|
|
: "=&r,&r" (result) \
|
|
: "r,0" (newvalue), "r,r" (mem) : "memory"); \
|
|
else \
|
|
{ \
|
|
result = 0; \
|
|
abort (); \
|
|
} \
|
|
result; })
|
|
|
|
/* Atomic compare and exchange. These sequences are not actually atomic;
|
|
there is a race if *MEM != OLDVAL and we are preempted between the two
|
|
swaps. However, they are very close to atomic, and are the best that a
|
|
pre-ARMv6 implementation can do without operating system support.
|
|
LinuxThreads has been using these sequences for many years. */
|
|
|
|
#define __arch_compare_and_exchange_val_8_acq(mem, newval, oldval) \
|
|
({ __typeof (oldval) result, tmp; \
|
|
__asm__ ("\n" \
|
|
"0:\tldr\t%1,[%2]\n\t" \
|
|
"cmp\t%1,%4\n\t" \
|
|
"movne\t%0,%1\n\t" \
|
|
"bne\t1f\n\t" \
|
|
"swpb\t%0,%3,[%2]\n\t" \
|
|
"cmp\t%1,%0\n\t" \
|
|
"swpbne\t%1,%0,[%2]\n\t" \
|
|
"bne\t0b\n\t" \
|
|
"1:" \
|
|
: "=&r" (result), "=&r" (tmp) \
|
|
: "r" (mem), "r" (newval), "r" (oldval) \
|
|
: "cc", "memory"); \
|
|
result; })
|
|
|
|
#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) result, tmp; \
|
|
__asm__ ("\n" \
|
|
"0:\tldr\t%1,[%2]\n\t" \
|
|
"cmp\t%1,%4\n\t" \
|
|
"movne\t%0,%1\n\t" \
|
|
"bne\t1f\n\t" \
|
|
"swp\t%0,%3,[%2]\n\t" \
|
|
"cmp\t%1,%0\n\t" \
|
|
"swpne\t%1,%0,[%2]\n\t" \
|
|
"bne\t0b\n\t" \
|
|
"1:" \
|
|
: "=&r" (result), "=&r" (tmp) \
|
|
: "r" (mem), "r" (newval), "r" (oldval) \
|
|
: "cc", "memory"); \
|
|
result; })
|
|
|
|
#define __arch_compare_and_exchange_val_64_acq(mem, newval, oldval) \
|
|
({ __arm_link_error (); oldval; })
|