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/* Common definition for ifunc selections optimized with SSE2 and SSE4.2.
All versions must be listed in ifunc-impl-list.c.
Copyright (C) 2017-2025 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <init-arch.h>
extern __typeof (REDIRECT_NAME) OPTIMIZE (generic) attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (sse42) attribute_hidden;
static inline void *
IFUNC_SELECTOR (void)
{
const struct cpu_features* cpu_features = __get_cpu_features ();
/* This function uses the `pcmpstri` sse4.2 instruction which can be
slow on some CPUs. This normally would be guarded by a
Slow_SSE4_2 check, but since there is no other optimized
implementation its best to keep it regardless. If an optimized
fallback is added add a X86_ISA_CPU_FEATURE_ARCH_P (cpu_features,
Slow_SSE4_2) check. */
if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, SSE4_2))
return OPTIMIZE (sse42);
return OPTIMIZE (generic);
}
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