1/* Common definition for ifunc selections optimized with SSE2 and AVX2.
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
22#ifndef GENERIC
23# define GENERIC sse2
24#endif
25
26extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
27
28extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
29extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
30
31extern __typeof (REDIRECT_NAME) OPTIMIZE (GENERIC) attribute_hidden;
32
33static inline void *
34IFUNC_SELECTOR (void)
35{
36 const struct cpu_features *cpu_features = __get_cpu_features ();
37
38 if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
39 && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI1)
40 && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, BMI2)
41 && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, LZCNT)
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 return OPTIMIZE (GENERIC);
58}
59

source code of glibc/sysdeps/x86_64/multiarch/ifunc-avx2.h