1  /* Common definition for memset/memset_chk ifunc selections.
       2     All versions must be listed in ifunc-impl-list.c.
       3     Copyright (C) 2017-2023 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     <https://www.gnu.org/licenses/>.  */
      19  
      20  #include <init-arch.h>
      21  
      22  extern __typeof (REDIRECT_NAME) OPTIMIZE (erms) attribute_hidden;
      23  
      24  extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned)
      25    attribute_hidden;
      26  extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned_erms)
      27    attribute_hidden;
      28  extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_no_vzeroupper)
      29    attribute_hidden;
      30  
      31  extern __typeof (REDIRECT_NAME) OPTIMIZE (evex_unaligned)
      32    attribute_hidden;
      33  extern __typeof (REDIRECT_NAME) OPTIMIZE (evex_unaligned_erms)
      34    attribute_hidden;
      35  
      36  extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_unaligned) attribute_hidden;
      37  extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_unaligned_erms)
      38    attribute_hidden;
      39  extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_unaligned_rtm)
      40    attribute_hidden;
      41  extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_unaligned_erms_rtm)
      42    attribute_hidden;
      43  
      44  extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned)
      45    attribute_hidden;
      46  extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned_erms)
      47    attribute_hidden;
      48  
      49  static inline void *
      50  IFUNC_SELECTOR (void)
      51  {
      52    const struct cpu_features *cpu_features = __get_cpu_features ();
      53  
      54    if (CPU_FEATURES_ARCH_P (cpu_features, Prefer_ERMS))
      55      return OPTIMIZE (erms);
      56  
      57    if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512F)
      58        && !CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_AVX512))
      59      {
      60        if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
      61  	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
      62  	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2))
      63  	{
      64  	  if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
      65  	    return OPTIMIZE (avx512_unaligned_erms);
      66  
      67  	  return OPTIMIZE (avx512_unaligned);
      68  	}
      69  
      70        return OPTIMIZE (avx512_no_vzeroupper);
      71      }
      72  
      73    if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2))
      74      {
      75        if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
      76  	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
      77  	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2))
      78  	{
      79  	  if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
      80  	    return OPTIMIZE (evex_unaligned_erms);
      81  
      82  	  return OPTIMIZE (evex_unaligned);
      83  	}
      84  
      85        if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
      86  	{
      87  	  if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
      88  	    return OPTIMIZE (avx2_unaligned_erms_rtm);
      89  
      90  	  return OPTIMIZE (avx2_unaligned_rtm);
      91  	}
      92  
      93        if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
      94  				       Prefer_No_VZEROUPPER, !))
      95  	{
      96  	  if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
      97  	    return OPTIMIZE (avx2_unaligned_erms);
      98  
      99  	  return OPTIMIZE (avx2_unaligned);
     100  	}
     101      }
     102  
     103    if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
     104      return OPTIMIZE (sse2_unaligned_erms);
     105  
     106    return OPTIMIZE (sse2_unaligned);
     107  }