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On Skylake server, AVX512 load/store instructions in memcpy/memset may lead to lower CPU turbo frequency in certain situations. Use of AVX2 in memcpy/memset has been observed to have improved overall performance in many workloads due to the higher frequency. Since AVX512ER is unique to Xeon Phi, this patch sets Prefer_No_AVX512 if AVX512ER isn't available so that AVX2 versions of memcpy/memset are used on Skylake server. [BZ #21396] * sysdeps/x86/cpu-features.c (init_cpu_features): Set Prefer_No_AVX512 if AVX512ER isn't available. * sysdeps/x86/cpu-features.h (bit_arch_Prefer_No_AVX512): New. (index_arch_Prefer_No_AVX512): Likewise. * sysdeps/x86_64/multiarch/memcpy.S (__new_memcpy): Don't use AVX512 version if Prefer_No_AVX512 is set. * sysdeps/x86_64/multiarch/memcpy_chk.S (__memcpy_chk): Likewise. * sysdeps/x86_64/multiarch/memmove.S (__libc_memmove): Likewise. * sysdeps/x86_64/multiarch/memmove_chk.S (__memmove_chk): Likewise. * sysdeps/x86_64/multiarch/mempcpy.S (__mempcpy): Likewise. * sysdeps/x86_64/multiarch/mempcpy_chk.S (__mempcpy_chk): Likewise. * sysdeps/x86_64/multiarch/memset.S (memset): Likewise. * sysdeps/x86_64/multiarch/memset_chk.S (__memset_chk): Likewise.
62 lines
2.0 KiB
ArmAsm
62 lines
2.0 KiB
ArmAsm
/* Multiple versions of memset_chk
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All versions must be listed in ifunc-impl-list.c.
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Copyright (C) 2014-2017 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<http://www.gnu.org/licenses/>. */
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#include <sysdep.h>
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#include <init-arch.h>
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/* Define multiple versions only for the definition in lib. */
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#if IS_IN (libc)
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# ifdef SHARED
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ENTRY(__memset_chk)
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.type __memset_chk, @gnu_indirect_function
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LOAD_RTLD_GLOBAL_RO_RDX
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lea __memset_chk_sse2_unaligned_erms(%rip), %RAX_LP
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HAS_CPU_FEATURE (ERMS)
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jnz 1f
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lea __memset_chk_sse2_unaligned(%rip), %RAX_LP
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1:
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HAS_ARCH_FEATURE (AVX2_Usable)
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jz 2f
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lea __memset_chk_avx2_unaligned_erms(%rip), %RAX_LP
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HAS_CPU_FEATURE (ERMS)
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jnz L(AVX512F)
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lea __memset_chk_avx2_unaligned(%rip), %RAX_LP
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L(AVX512F):
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HAS_ARCH_FEATURE (Prefer_No_AVX512)
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jnz 2f
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HAS_ARCH_FEATURE (AVX512F_Usable)
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jz 2f
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lea __memset_chk_avx512_no_vzeroupper(%rip), %RAX_LP
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HAS_ARCH_FEATURE (Prefer_No_VZEROUPPER)
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jnz 2f
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lea __memset_chk_avx512_unaligned_erms(%rip), %RAX_LP
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HAS_CPU_FEATURE (ERMS)
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jnz 2f
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lea __memset_chk_avx512_unaligned(%rip), %RAX_LP
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2: ret
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END(__memset_chk)
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strong_alias (__memset_chk, __memset_zero_constant_len_parameter)
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.section .gnu.warning.__memset_zero_constant_len_parameter
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.string "memset used with constant zero length parameter; this could be due to transposed parameters"
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# else
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# include "../memset_chk.S"
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# endif
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#endif
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