sysdeps/x86_64/multiarch/init-arch.h

   1 /* This file is part of the GNU C Library.
   2    Copyright (C) 2008, 2009 Free Software Foundation, Inc.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <sys/param.h>
  20
  21 enum
  22   {
  23     COMMON_CPUID_INDEX_1 = 0,
  24     /* Keep the following line at the end.  */
  25     COMMON_CPUID_INDEX_MAX
  26   };
  27
  28 extern struct cpu_features
  29 {
  30   enum
  31     {
  32       arch_kind_unknown = 0,
  33       arch_kind_intel,
  34       arch_kind_amd,
  35       arch_kind_other
  36     } kind;
  37   int max_cpuid;
  38   struct cpuid_registers
  39   {
  40     unsigned int eax;
  41     unsigned int ebx;
  42     unsigned int ecx;
  43     unsigned int edx;
  44   } cpuid[COMMON_CPUID_INDEX_MAX];
  45   unsigned int family;
  46   unsigned int model;
  47 } __cpu_features attribute_hidden;
  48
  49
  50 extern void __init_cpu_features (void) attribute_hidden;
  51 #define INIT_ARCH()\
  52   do                                                    \
  53     if (__cpu_features.kind == arch_kind_unknown)       \
  54       __init_cpu_features ();                           \
  55   while (0)
  56
  57 /* Following are the feature tests used throughout libc.  */
  58
  59 #define HAS_POPCOUNT \
  60   ((__cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx & (1 << 23)) != 0)
  61
  62 #define HAS_SSE4_2 \
  63   ((__cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx & (1 << 20)) != 0)