1/* Common definition for __memcmpeq ifunc selections.
2 All versions must be listed in ifunc-impl-list.c.
3 Copyright (C) 2017-2024 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) OPTIMIZE1 (evex) attribute_hidden;
23
24extern __typeof (REDIRECT_NAME) OPTIMIZE1 (avx2) attribute_hidden;
25extern __typeof (REDIRECT_NAME) OPTIMIZE1 (avx2_rtm) attribute_hidden;
26
27extern __typeof (REDIRECT_NAME) OPTIMIZE1 (sse2) attribute_hidden;
28
29static inline void *
30IFUNC_SELECTOR (void)
31{
32 const struct cpu_features *cpu_features = __get_cpu_features ();
33
34 if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
35 && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2)
36 && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
37 AVX_Fast_Unaligned_Load, ))
38 {
39 if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
40 && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
41 return OPTIMIZE1 (evex);
42
43 if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
44 return OPTIMIZE1 (avx2_rtm);
45
46 if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
47 Prefer_No_VZEROUPPER, !))
48 return OPTIMIZE1 (avx2);
49 }
50
51 return OPTIMIZE1 (sse2);
52}
53

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