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Diffstat (limited to 'libc/sysdeps/linux/kvx/bits/atomic.h')
| -rw-r--r-- | libc/sysdeps/linux/kvx/bits/atomic.h | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/kvx/bits/atomic.h b/libc/sysdeps/linux/kvx/bits/atomic.h new file mode 100644 index 000000000..3c423e9ba --- /dev/null +++ b/libc/sysdeps/linux/kvx/bits/atomic.h @@ -0,0 +1,141 @@ +/* Copyright (C) 2010-2012 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Maxim Kuvyrkov <maxim@codesourcery.com>, 2010. + + 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, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _KVX_BITS_ATOMIC_H +#define _KVX_BITS_ATOMIC_H + +#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 atomic_full_barrier +# define atomic_full_barrier() do { atomic_read_barrier(); \ + atomic_write_barrier(); } while(0) +#endif + +#ifndef atomic_read_barrier +# define atomic_read_barrier() __builtin_kvx_dinval() +#endif + +#ifndef atomic_write_barrier +# define atomic_write_barrier() __builtin_kvx_fence() +#endif + +/* + * On kvx, we have a boolean compare and swap which means that the operation + * returns only the success of operation. + * If operation succeeds, this is simple, we just need to return the provided + * old value. However, if it fails, we need to load the value to return it for + * the caller. If the loaded value is different from the "old" provided by the + * caller, we can return it since it will mean it failed. + * However, if for some reason the value we read is equal to the old value + * provided by the caller, we can't simply return it or the caller will think it + * succeeded. So if the value we read is the same as the "old" provided by + * the caller, we try again until either we succeed or we fail with a different + * value than the provided one. + */ +#define __cmpxchg(ptr, old, new, op_suffix, load_suffix) \ +({ \ + register unsigned long __rn __asm__("r62"); \ + register unsigned long __ro __asm__("r63"); \ + __asm__ __volatile__ ( \ + /* Fence to guarantee previous store to be committed */ \ + "fence\n" \ + /* Init "expect" with previous value */ \ + "copyd $r63 = %[rOld]\n" \ + ";;\n" \ + "1:\n" \ + /* Init "update" value with new */ \ + "copyd $r62 = %[rNew]\n" \ + ";;\n" \ + "acswap" #op_suffix " 0[%[rPtr]], $r62r63\n" \ + ";;\n" \ + /* if acswap succeeds, simply return */ \ + "cb.dnez $r62? 2f\n" \ + ";;\n" \ + /* We failed, load old value */ \ + "l" #op_suffix #load_suffix" $r63 = 0[%[rPtr]]\n" \ + ";;\n" \ + /* Check if equal to "old" one */ \ + "compd.ne $r62 = $r63, %[rOld]\n" \ + ";;\n" \ + /* If different from "old", return it to caller */ \ + "cb.deqz $r62? 1b\n" \ + ";;\n" \ + "2:\n" \ + : "+r" (__rn), "+r" (__ro) \ + : [rPtr] "r" (ptr), [rOld] "r" (old), [rNew] "r" (new) \ + : "memory"); \ + (__ro); \ +}) + +#define cmpxchg(ptr, o, n) \ +({ \ + unsigned long __cmpxchg__ret; \ + switch (sizeof(*(ptr))) { \ + case 4: \ + __cmpxchg__ret = __cmpxchg((ptr), (o), (n), w, s); \ + break; \ + case 8: \ + __cmpxchg__ret = __cmpxchg((ptr), (o), (n), d, ); \ + break; \ + } \ + (__typeof(*(ptr))) (__cmpxchg__ret); \ +}) + +#define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \ + cmpxchg((mem), (oldval), (newval)) + + +#define atomic_exchange_acq(mem, newval) \ +({ \ + unsigned long __aea__ret, __aea__old; \ + volatile __typeof((mem)) __aea__m = (mem); \ + do { \ + __aea__old = *__aea__m; \ + __aea__ret = atomic_compare_and_exchange_val_acq((mem), \ + (newval), (__aea__old));\ + } while (__aea__old != __aea__ret); \ + (__aea__old); \ +}) + +#endif |