sysdeps/x86_64/multiarch/ifunc-memmove.h

   1 /* Common definition for memcpy, mempcpy and memmove implementation.
   2    All versions must be listed in ifunc-impl-list.c.
   3    Copyright (C) 2017-2018 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <init-arch.h>
  21
  22 extern __typeof (REDIRECT_NAME) OPTIMIZE (erms) attribute_hidden;
  23 extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned)
  24   attribute_hidden;
  25 extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned_erms)
  26   attribute_hidden;
  27 extern __typeof (REDIRECT_NAME) OPTIMIZE (ssse3) attribute_hidden;
  28 extern __typeof (REDIRECT_NAME) OPTIMIZE (ssse3_back) attribute_hidden;
  29 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned) attribute_hidden;
  30 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned_erms)
  31   attribute_hidden;
  32 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned)
  33   attribute_hidden;
  34 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned_erms)
  35   attribute_hidden;
  36 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_no_vzeroupper)
  37   attribute_hidden;
  38
  39 static inline void *
  40 IFUNC_SELECTOR (void)
  41 {
  42   const struct cpu_features* cpu_features = __get_cpu_features ();
  43
  44   if (CPU_FEATURES_ARCH_P (cpu_features, Prefer_ERMS)
  45       || CPU_FEATURES_ARCH_P (cpu_features, Prefer_FSRM))
  46     return OPTIMIZE (erms);
  47
  48   if (CPU_FEATURES_ARCH_P (cpu_features, AVX512F_Usable)
  49       && !CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_AVX512))
  50     {
  51       if (CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
  52         return OPTIMIZE (avx512_no_vzeroupper);
  53
  54       if (CPU_FEATURES_CPU_P (cpu_features, ERMS))
  55         return OPTIMIZE (avx512_unaligned_erms);
  56
  57       return OPTIMIZE (avx512_unaligned);
  58     }
  59
  60   if (CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
  61     {
  62       if (CPU_FEATURES_CPU_P (cpu_features, ERMS))
  63         return OPTIMIZE (avx_unaligned_erms);
  64
  65       return OPTIMIZE (avx_unaligned);
  66     }
  67
  68   if (!CPU_FEATURES_CPU_P (cpu_features, SSSE3)
  69       || CPU_FEATURES_ARCH_P (cpu_features, Fast_Unaligned_Copy))
  70     {
  71       if (CPU_FEATURES_CPU_P (cpu_features, ERMS))
  72         return OPTIMIZE (sse2_unaligned_erms);
  73
  74       return OPTIMIZE (sse2_unaligned);
  75     }
  76
  77   if (CPU_FEATURES_ARCH_P (cpu_features, Fast_Copy_Backward))
  78     return OPTIMIZE (ssse3_back);
  79
  80   return OPTIMIZE (ssse3);
  81 }