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
22extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
23extern __typeof (REDIRECT_NAME) OPTIMIZE (sse4_1) attribute_hidden;
24extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
25extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
26extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
27
28static inline void *
29IFUNC_SELECTOR (void)
30{
31 const struct cpu_features* cpu_features = __get_cpu_features ();
32
33 if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
34 && CPU_FEATURE_USABLE_P (cpu_features, BMI2)
35 && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
36 {
37 if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
38 && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
39 return OPTIMIZE (evex);
40
41 if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
42 return OPTIMIZE (avx2_rtm);
43
44 if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
45 return OPTIMIZE (avx2);
46 }
47
48 if (CPU_FEATURE_USABLE_P (cpu_features, SSE4_1))
49 return OPTIMIZE (sse4_1);
50
51 return OPTIMIZE (sse2);
52}
53

source code of glibc/sysdeps/x86_64/multiarch/ifunc-wcslen.h