1 /* Multiple versions of strncmp.
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.
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.
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.
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/>. */
20 /* Define multiple versions only for the definition in libc. */
22 # define strncmp __redirect_strncmp
26 # define SYMBOL_NAME strncmp
27 # include <init-arch.h>
29 extern __typeof (REDIRECT_NAME
) OPTIMIZE (evex
) attribute_hidden
;
31 extern __typeof (REDIRECT_NAME
) OPTIMIZE (avx2
) attribute_hidden
;
32 extern __typeof (REDIRECT_NAME
) OPTIMIZE (avx2_rtm
) attribute_hidden
;
34 extern __typeof (REDIRECT_NAME
) OPTIMIZE (sse42
) attribute_hidden
;
36 extern __typeof (REDIRECT_NAME
) OPTIMIZE (sse2
) attribute_hidden
;
41 const struct cpu_features
*cpu_features
= __get_cpu_features ();
43 if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features
, AVX2
)
44 && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features
, BMI2
)
45 && X86_ISA_CPU_FEATURES_ARCH_P (cpu_features
,
46 AVX_Fast_Unaligned_Load
, ))
48 if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features
, AVX512VL
)
49 && X86_ISA_CPU_FEATURE_USABLE_P (cpu_features
, AVX512BW
))
50 return OPTIMIZE (evex
);
52 if (CPU_FEATURE_USABLE_P (cpu_features
, RTM
))
53 return OPTIMIZE (avx2_rtm
);
55 if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features
,
56 Prefer_No_VZEROUPPER
, !))
57 return OPTIMIZE (avx2
);
60 if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features
, SSE4_2
)
61 && !CPU_FEATURES_ARCH_P (cpu_features
, Slow_SSE4_2
))
62 return OPTIMIZE (sse42
);
64 return OPTIMIZE (sse2
);
67 libc_ifunc_redirected (__redirect_strncmp
, strncmp
, IFUNC_SELECTOR ());
70 __hidden_ver1 (strncmp
, __GI_strncmp
, __redirect_strncmp
)
71 __attribute__ ((visibility ("hidden"))) __attribute_copy__ (strncmp
);