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The C and C++ Include Header Files

/usr/include/x86_64-linux-gnu/sys/platform/x86.h


$ cat -n /usr/include/x86_64-linux-gnu/sys/platform/x86.h

     1	/* Data structure for x86 CPU features.
     2	   This file is part of the GNU C Library.
     3	   Copyright (C) 2008-2024 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.  */
    30	extern const struct cpuid_feature *__x86_get_cpuid_feature_leaf (unsigned int)
    31	     __attribute__ ((pure));
    32	
    33	static __inline__ _Bool
    34	x86_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	
    46	static __inline__ _Bool
    47	x86_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 */