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/*
* Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
* Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
* Copyright (c) 1999-2003 by Hewlett-Packard Company. All rights reserved.
*
*
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
*
* Permission is hereby granted to use or copy this program
* for any purpose, provided the above notices are retained on all copies.
* Permission to modify the code and to distribute modified code is granted,
* provided the above notices are retained, and a notice that the code was
* modified is included with the above copyright notice.
*
*/
/* TODO: Very incomplete; Add support for sparc64. */
/* Non-ancient SPARCs provide compare-and-swap (casa). */
#include "../all_atomic_load_store.h"
/* Real SPARC code uses TSO: */
#include "../ordered_except_wr.h"
/* Test_and_set location is just a byte. */
#include "../test_and_set_t_is_char.h"
AO_INLINE AO_TS_VAL_t
AO_test_and_set_full(volatile AO_TS_t *addr) {
AO_TS_VAL_t oldval;
__asm__ __volatile__("ldstub %1,%0"
: "=r"(oldval), "=m"(*addr)
: "m"(*addr) : "memory");
return oldval;
}
#define AO_HAVE_test_and_set_full
#ifndef AO_NO_SPARC_V9
/* Returns nonzero if the comparison succeeded. */
AO_INLINE int
AO_compare_and_swap_full(volatile AO_t *addr, AO_t old, AO_t new_val) {
char ret;
__asm__ __volatile__ ("membar #StoreLoad | #LoadLoad\n\t"
# if defined(__arch64__)
"casx [%2],%0,%1\n\t"
# else
"cas [%2],%0,%1\n\t" /* 32-bit version */
# endif
"membar #StoreLoad | #StoreStore\n\t"
"cmp %0,%1\n\t"
"be,a 0f\n\t"
"mov 1,%0\n\t"/* one insn after branch always executed */
"clr %0\n\t"
"0:\n\t"
: "=r" (ret), "+r" (new_val)
: "r" (addr), "0" (old)
: "memory", "cc");
return (int)ret;
}
#define AO_HAVE_compare_and_swap_full
/* TODO: implement AO_fetch_compare_and_swap. */
#endif /* !AO_NO_SPARC_V9 */
/* TODO: Extend this for SPARC v8 and v9 (V8 also has swap, V9 has CAS, */
/* there are barriers like membar #LoadStore, CASA (32-bit) and */
/* CASXA (64-bit) instructions added in V9). */
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