1 /* Common definition for ifunc selections for wcslen and wcsnlen
2    All versions must be listed in ifunc-impl-list.c.
3    Copyright (C) 2017-2022 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 #ifndef GENERIC
23 # define GENERIC sse2
24 #endif
25 
26 extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
27 
28 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
29 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
30 
31 extern __typeof (REDIRECT_NAME) OPTIMIZE (sse4_1) attribute_hidden;
32 
33 extern __typeof (REDIRECT_NAME) OPTIMIZE (GENERIC) attribute_hidden;
34 
35 static inline void *
IFUNC_SELECTOR(void)36 IFUNC_SELECTOR (void)
37 {
38   const struct cpu_features *cpu_features = __get_cpu_features ();
39 
40   if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
41       && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2)
42       && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
43 				      AVX_Fast_Unaligned_Load, ))
44     {
45       if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
46 	  && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
47 	return OPTIMIZE (evex);
48 
49       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
50 	return OPTIMIZE (avx2_rtm);
51 
52       if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
53 				       Prefer_No_VZEROUPPER, !))
54 	return OPTIMIZE (avx2);
55     }
56 
57   if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, SSE4_1))
58     return OPTIMIZE (sse4_1);
59 
60   return OPTIMIZE (GENERIC);
61 }
62