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Diffstat (limited to 'sysdeps/arm/atomicity.h')
| -rw-r--r-- | sysdeps/arm/atomicity.h | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/sysdeps/arm/atomicity.h b/sysdeps/arm/atomicity.h new file mode 100644 index 0000000000..1a437a6d35 --- /dev/null +++ b/sysdeps/arm/atomicity.h @@ -0,0 +1,87 @@ +/* Low-level functions for atomic operations. ARM version. + Copyright (C) 1997, 1998, 1999, 2000 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. */ + +#ifndef _ATOMICITY_H +#define _ATOMICITY_H 1 + +#include <inttypes.h> + + +static inline int +__attribute__ ((unused)) +exchange_and_add (volatile uint32_t *mem, int val) +{ + int tmp1; + int tmp2; + int result; + __asm__ ("\n" + "0:\tldr\t%0,[%3]\n\t" + "add\t%1,%0,%4\n\t" + "swp\t%2,%1,[%3]\n\t" + "cmp\t%0,%2\n\t" + "swpne\t%1,%2,[%3]\n\t" + "bne\t0b" + : "=&r" (result), "=&r" (tmp1), "=&r" (tmp2) + : "r" (mem), "r"(val) + : "cc", "memory"); + return result; +} + +static inline void +__attribute__ ((unused)) +atomic_add (volatile uint32_t *mem, int val) +{ + int tmp1; + int tmp2; + int tmp3; + __asm__ ("\n" + "0:\tldr\t%0,[%3]\n\t" + "add\t%1,%0,%4\n\t" + "swp\t%2,%1,[%3]\n\t" + "cmp\t%0,%2\n\t" + "swpne\t%1,%2,[%3]\n\t" + "bne\t0b" + : "=&r" (tmp1), "=&r" (tmp2), "=&r" (tmp3) + : "r" (mem), "r"(val) + : "cc", "memory"); +} + +static inline int +__attribute__ ((unused)) +compare_and_swap (volatile long int *p, long int oldval, long int newval) +{ + int result, tmp; + __asm__ ("\n" + "0:\tldr\t%1,[%2]\n\t" + "mov\t%0,#0\n\t" + "cmp\t%1,%4\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" + "mov\t%0,#1\n" + "1:" + : "=&r" (result), "=&r" (tmp) + : "r" (p), "r" (newval), "r" (oldval) + : "cc", "memory"); + return result; +} + +#endif /* atomicity.h */ |