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/* Common definition for memcpy, mempcpy and memmove implementation.
All versions must be listed in ifunc-impl-list.c.
Copyright (C) 2017-2024 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 (erms) attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_unaligned_erms)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (avx512_no_vzeroupper)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (evex_unaligned)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (evex_unaligned_erms)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned) attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned_erms)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned_rtm)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (avx_unaligned_erms_rtm)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (ssse3) attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned_erms)
attribute_hidden;
static inline void *
inhibit_stack_protector
IFUNC_SELECTOR (void)
{
const struct cpu_features *cpu_features = __get_cpu_features ();
if (CPU_FEATURES_ARCH_P (cpu_features, Prefer_ERMS)
|| CPU_FEATURES_ARCH_P (cpu_features, Prefer_FSRM))
return OPTIMIZE (erms);
if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512F)
&& !CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_AVX512))
{
if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL))
{
if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
return OPTIMIZE (avx512_unaligned_erms);
return OPTIMIZE (avx512_unaligned);
}
return OPTIMIZE (avx512_no_vzeroupper);
}
if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
AVX_Fast_Unaligned_Load, ))
{
if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX512VL))
{
if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
return OPTIMIZE (evex_unaligned_erms);
return OPTIMIZE (evex_unaligned);
}
if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
{
if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
return OPTIMIZE (avx_unaligned_erms_rtm);
return OPTIMIZE (avx_unaligned_rtm);
}
if (X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
Prefer_No_VZEROUPPER, !))
{
if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
return OPTIMIZE (avx_unaligned_erms);
return OPTIMIZE (avx_unaligned);
}
}
if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, SSSE3)
/* Leave this as runtime check. The SSSE3 is optimized almost
exclusively for avoiding unaligned memory access during the
copy and by and large is not better than the sse2
implementation as a general purpose memmove. */
&& !CPU_FEATURES_ARCH_P (cpu_features, Fast_Unaligned_Copy))
{
return OPTIMIZE (ssse3);
}
if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
return OPTIMIZE (sse2_unaligned_erms);
return OPTIMIZE (sse2_unaligned);
}
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