1 /* Common definition for memcpy, mempcpy and memmove implementation.
2    All versions must be listed in ifunc-impl-list.c.
3    Copyright (C) 2017-2021 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 extern __typeof (REDIRECT_NAME) OPTIMIZE (erms) attribute_hidden;
23 extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned)
24   attribute_hidden;
25 extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned_erms)
26   attribute_hidden;
27 extern __typeof (REDIRECT_NAME) OPTIMIZE (ssse3) attribute_hidden;
28 extern __typeof (REDIRECT_NAME) OPTIMIZE (ssse3_back) attribute_hidden;
29 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned) attribute_hidden;
30 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned_erms)
31   attribute_hidden;
32 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned_rtm)
33   attribute_hidden;
34 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned_erms_rtm)
35   attribute_hidden;
36 extern __typeof (REDIRECT_NAME) OPTIMIZE (evex_unaligned)
37   attribute_hidden;
38 extern __typeof (REDIRECT_NAME) OPTIMIZE (evex_unaligned_erms)
39   attribute_hidden;
40 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned)
41   attribute_hidden;
42 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned_erms)
43   attribute_hidden;
44 extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_no_vzeroupper)
45   attribute_hidden;
46 
47 static inline void *
IFUNC_SELECTOR(void)48 IFUNC_SELECTOR (void)
49 {
50   const struct cpu_features* cpu_features = __get_cpu_features ();
51 
52   if (CPU_FEATURES_ARCH_P (cpu_features, Prefer_ERMS)
53       || CPU_FEATURES_ARCH_P (cpu_features, Prefer_FSRM))
54     return OPTIMIZE (erms);
55 
56   if (CPU_FEATURE_USABLE_P (cpu_features, AVX512F)
57       && !CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_AVX512))
58     {
59       if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL))
60 	{
61 	  if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
62 	    return OPTIMIZE (avx512_unaligned_erms);
63 
64 	  return OPTIMIZE (avx512_unaligned);
65 	}
66 
67       return OPTIMIZE (avx512_no_vzeroupper);
68     }
69 
70   if (CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
71     {
72       if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL))
73 	{
74 	  if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
75 	    return OPTIMIZE (evex_unaligned_erms);
76 
77 	  return OPTIMIZE (evex_unaligned);
78 	}
79 
80       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
81 	{
82 	  if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
83 	    return OPTIMIZE (avx_unaligned_erms_rtm);
84 
85 	  return OPTIMIZE (avx_unaligned_rtm);
86 	}
87 
88       if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
89 	{
90 	  if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
91 	    return OPTIMIZE (avx_unaligned_erms);
92 
93 	  return OPTIMIZE (avx_unaligned);
94 	}
95     }
96 
97   if (!CPU_FEATURE_USABLE_P (cpu_features, SSSE3)
98       || CPU_FEATURES_ARCH_P (cpu_features, Fast_Unaligned_Copy))
99     {
100       if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
101 	return OPTIMIZE (sse2_unaligned_erms);
102 
103       return OPTIMIZE (sse2_unaligned);
104     }
105 
106   if (CPU_FEATURES_ARCH_P (cpu_features, Fast_Copy_Backward))
107     return OPTIMIZE (ssse3_back);
108 
109   return OPTIMIZE (ssse3);
110 }
111