1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
/* Copyright (C) 2012-2018 Free Software Foundation, Inc.
Contributed by Richard Henderson <rth@redhat.com>.
This file is part of the GNU Atomic Library (libatomic).
Libatomic is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
Libatomic 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 General Public License for
more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#if HAVE_IFUNC
#include <cpuid.h>
extern unsigned int libat_feat1_ecx HIDDEN;
extern unsigned int libat_feat1_edx HIDDEN;
#ifdef __x86_64__
# define IFUNC_COND_1 (libat_feat1_ecx & bit_CMPXCHG16B)
#else
# define IFUNC_COND_1 (libat_feat1_edx & bit_CMPXCHG8B)
#endif
#ifdef __x86_64__
# define IFUNC_NCOND(N) (N == 16)
#else
# define IFUNC_NCOND(N) (N == 8)
#endif
#ifdef __x86_64__
# undef MAYBE_HAVE_ATOMIC_CAS_16
# define MAYBE_HAVE_ATOMIC_CAS_16 IFUNC_COND_1
# undef MAYBE_HAVE_ATOMIC_EXCHANGE_16
# define MAYBE_HAVE_ATOMIC_EXCHANGE_16 IFUNC_COND_1
# undef MAYBE_HAVE_ATOMIC_LDST_16
# define MAYBE_HAVE_ATOMIC_LDST_16 IFUNC_COND_1
/* Since load and store are implemented with CAS, they are not fast. */
# undef FAST_ATOMIC_LDST_16
# define FAST_ATOMIC_LDST_16 0
# if IFUNC_ALT == 1
# undef HAVE_ATOMIC_CAS_16
# define HAVE_ATOMIC_CAS_16 1
# endif
#else
# undef MAYBE_HAVE_ATOMIC_CAS_8
# define MAYBE_HAVE_ATOMIC_CAS_8 IFUNC_COND_1
# undef MAYBE_HAVE_ATOMIC_EXCHANGE_8
# define MAYBE_HAVE_ATOMIC_EXCHANGE_8 IFUNC_COND_1
# undef MAYBE_HAVE_ATOMIC_LDST_8
# define MAYBE_HAVE_ATOMIC_LDST_8 IFUNC_COND_1
# if IFUNC_ALT == 1
# undef HAVE_ATOMIC_CAS_8
# define HAVE_ATOMIC_CAS_8 1
# endif
#endif
#if defined(__x86_64__) && N == 16 && IFUNC_ALT == 1
static inline bool
atomic_compare_exchange_n (UTYPE *mptr, UTYPE *eptr, UTYPE newval,
bool weak_p UNUSED, int sm UNUSED, int fm UNUSED)
{
UTYPE cmpval = *eptr;
UTYPE oldval = __sync_val_compare_and_swap_16 (mptr, cmpval, newval);
if (oldval == cmpval)
return true;
*eptr = oldval;
return false;
}
# define atomic_compare_exchange_n atomic_compare_exchange_n
#endif /* Have CAS 16 */
#endif /* HAVE_IFUNC */
#include_next <host-config.h>
|
