1/* Data structure for x86 CPU features.
 2   This file is part of the GNU C Library.
 3   Copyright (C) 2008-2025 Free Software Foundation, Inc.
 4
 5   The GNU C Library is free software; you can redistribute it and/or
 6   modify it under the terms of the GNU Lesser General Public
 7   License as published by the Free Software Foundation; either
 8   version 2.1 of the License, or (at your option) any later version.
 9
10   The GNU C Library is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   Lesser General Public License for more details.
14
15   You should have received a copy of the GNU Lesser General Public
16   License along with the GNU C Library; if not, see
17   <https://www.gnu.org/licenses/>.  */
18
19#ifndef _SYS_PLATFORM_X86_H
20#define _SYS_PLATFORM_X86_H
21
22#include <features.h>
23#include <stdbool.h>
24#include <bits/platform/x86.h>
25#include <bits/platform/features.h>
26
27__BEGIN_DECLS
28
29/* Get a pointer to the CPU feature structure.  */
30extern const struct cpuid_feature *__x86_get_cpuid_feature_leaf (unsigned int)
31     __attribute__ ((pure));
32
33static __inline__ bool
34x86_cpu_present (unsigned int __index)
35{
36  const struct cpuid_feature *__ptr = __x86_get_cpuid_feature_leaf
37    (__index / (8 * sizeof (unsigned int) * 4));
38  unsigned int __reg
39     = __index & (8 * sizeof (unsigned int) * 4 - 1);
40  unsigned int __bit = __reg & (8 * sizeof (unsigned int) - 1);
41  __reg /= 8 * sizeof (unsigned int);
42
43  return __ptr->cpuid_array[__reg] & (1 << __bit);
44}
45
46static __inline__ bool
47x86_cpu_active (unsigned int __index)
48{
49  if (__index == x86_cpu_IBT || __index == x86_cpu_SHSTK)
50    return x86_cpu_cet_active (__index);
51
52  const struct cpuid_feature *__ptr = __x86_get_cpuid_feature_leaf
53    (__index / (8 * sizeof (unsigned int) * 4));
54  unsigned int __reg
55     = __index & (8 * sizeof (unsigned int) * 4 - 1);
56  unsigned int __bit = __reg & (8 * sizeof (unsigned int) - 1);
57  __reg /= 8 * sizeof (unsigned int);
58
59  return __ptr->active_array[__reg] & (1 << __bit);
60}
61
62/* CPU_FEATURE_PRESENT evaluates to true if CPU supports the feature.  */
63#define CPU_FEATURE_PRESENT(name) x86_cpu_present (x86_cpu_##name)
64/* CPU_FEATURE_ACTIVE evaluates to true if the feature is active.  */
65#define CPU_FEATURE_ACTIVE(name) x86_cpu_active (x86_cpu_##name)
66
67__END_DECLS
68
69#endif  /* _SYS_PLATFORM_X86_H */