1/* Common definition for memset/memset_chk ifunc selections.
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 (erms) attribute_hidden;
23extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned)
24 attribute_hidden;
25extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned_erms)
26 attribute_hidden;
27extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_unaligned) attribute_hidden;
28extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_unaligned_erms)
29 attribute_hidden;
30extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_unaligned_rtm)
31 attribute_hidden;
32extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_unaligned_erms_rtm)
33 attribute_hidden;
34extern __typeof (REDIRECT_NAME) OPTIMIZE (evex_unaligned)
35 attribute_hidden;
36extern __typeof (REDIRECT_NAME) OPTIMIZE (evex_unaligned_erms)
37 attribute_hidden;
38extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned)
39 attribute_hidden;
40extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned_erms)
41 attribute_hidden;
42extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_no_vzeroupper)
43 attribute_hidden;
44
45static inline void *
46IFUNC_SELECTOR (void)
47{
48 const struct cpu_features* cpu_features = __get_cpu_features ();
49
50 if (CPU_FEATURES_ARCH_P (cpu_features, Prefer_ERMS))
51 return OPTIMIZE (erms);
52
53 if (CPU_FEATURE_USABLE_P (cpu_features, AVX512F)
54 && !CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_AVX512))
55 {
56 if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
57 && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
58 && CPU_FEATURE_USABLE_P (cpu_features, BMI2))
59 {
60 if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
61 return OPTIMIZE (avx512_unaligned_erms);
62
63 return OPTIMIZE (avx512_unaligned);
64 }
65
66 return OPTIMIZE (avx512_no_vzeroupper);
67 }
68
69 if (CPU_FEATURE_USABLE_P (cpu_features, AVX2))
70 {
71 if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
72 && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
73 && CPU_FEATURE_USABLE_P (cpu_features, BMI2))
74 {
75 if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
76 return OPTIMIZE (evex_unaligned_erms);
77
78 return OPTIMIZE (evex_unaligned);
79 }
80
81 if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
82 {
83 if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
84 return OPTIMIZE (avx2_unaligned_erms_rtm);
85
86 return OPTIMIZE (avx2_unaligned_rtm);
87 }
88
89 if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
90 {
91 if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
92 return OPTIMIZE (avx2_unaligned_erms);
93
94 return OPTIMIZE (avx2_unaligned);
95 }
96 }
97
98 if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
99 return OPTIMIZE (sse2_unaligned_erms);
100
101 return OPTIMIZE (sse2_unaligned);
102}
103

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