/* * Copyright (c) 2003 Hewlett-Packard Development Company, L.P. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include "../read_ordered.h" #ifndef AO_ASSUME_WINDOWS98 /* CAS is always available */ # define AO_ASSUME_WINDOWS98 #endif #include "common32_defs.h" /* FIXME: Do _InterlockedOps really have a full memory barrier? */ /* (MSDN WinCE docs say nothing about it.) */ #if _M_ARM >= 6 /* ARMv6 is the first architecture providing support for simple LL/SC. */ #include "../standard_ao_double_t.h" /* If only a single processor is used, we can define AO_UNIPROCESSOR */ /* and do not need to access CP15 for ensuring a DMB at all. */ #ifdef AO_UNIPROCESSOR AO_INLINE void AO_nop_full(void) {} # define AO_HAVE_nop_full #else /* AO_nop_full() is emulated using AO_test_and_set_full(). */ #endif #include "../test_and_set_t_is_ao_t.h" /* AO_test_and_set() is emulated using CAS. */ AO_INLINE AO_t AO_load(const volatile AO_t *addr) { /* Cast away the volatile in case it adds fence semantics */ return (*(const AO_t *)addr); } #define AO_HAVE_load AO_INLINE void AO_store_full(volatile AO_t *addr, AO_t value) { /* Emulate atomic store using CAS. */ AO_t old = AO_load(addr); AO_t current; # ifdef AO_OLD_STYLE_INTERLOCKED_COMPARE_EXCHANGE while ((current = (AO_t)_InterlockedCompareExchange( (PVOID AO_INTERLOCKED_VOLATILE *)addr, (PVOID)value, (PVOID)old)) != old) old = current; # else while ((current = (AO_t)_InterlockedCompareExchange( (LONG AO_INTERLOCKED_VOLATILE *)addr, (LONG)value, (LONG)old)) != old) old = current; # endif } #define AO_HAVE_store_full /* FIXME: implement AO_compare_double_and_swap_double() */ #else /* _M_ARM < 6 */ /* Some slide set, if it has been red correctly, claims that Loads */ /* followed by either a Load or a Store are ordered, but nothing */ /* else is. It appears that SWP is the only simple memory barrier. */ #include "../all_atomic_load_store.h" #include "../test_and_set_t_is_ao_t.h" /* AO_test_and_set_full() is emulated using CAS. */ #endif /* _M_ARM < 6 */