1/* Common definition for ifunc selections optimized with SSE2, unaligned
2 SSE2 and SSSE3.
3 All versions must be listed in ifunc-impl-list.c.
4 Copyright (C) 2017-2024 Free Software Foundation, Inc.
5 This file is part of the GNU C Library.
6
7 The GNU C Library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Lesser General Public
9 License as published by the Free Software Foundation; either
10 version 2.1 of the License, or (at your option) any later version.
11
12 The GNU C Library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
16
17 You should have received a copy of the GNU Lesser General Public
18 License along with the GNU C Library; if not, see
19 <https://www.gnu.org/licenses/>. */
20
21#include <init-arch.h>
22
23extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
24
25extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
26extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
27
28extern __typeof (REDIRECT_NAME)
29 OPTIMIZE (sse2_unaligned) attribute_hidden;
30
31extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) 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_FEATURES_ARCH_P (cpu_features,
40 AVX_Fast_Unaligned_Load, ))
41 {
42 if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
43 && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
44 return OPTIMIZE (evex);
45
46 if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
47 return OPTIMIZE (avx2_rtm);
48
49 if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
50 Prefer_No_VZEROUPPER, !))
51 return OPTIMIZE (avx2);
52 }
53
54 if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features, Fast_Unaligned_Load, ))
55 return OPTIMIZE (sse2_unaligned);
56
57 return OPTIMIZE (sse2);
58}
59

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