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a7392db2ff
No bug.
The optimizations are as follows:
1) Always align entry to 64 bytes. This makes behavior more
predictable and makes other frontend optimizations easier.
2) Make the L(more_8x_vec) cases 4k aliasing aware. This can have
significant benefits in the case that:
0 < (dst - src) < [256, 512]
3) Align before `rep movsb`. For ERMS this is roughly a [0, 30%]
improvement and for FSRM [-10%, 25%].
In addition to these primary changes there is general cleanup
throughout to optimize the aligning routines and control flow logic.
Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com>
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit a6b7502ec0)
72 lines
2.0 KiB
ArmAsm
72 lines
2.0 KiB
ArmAsm
/* Optimized memmove for x86-64.
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Copyright (C) 2016-2021 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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<https://www.gnu.org/licenses/>. */
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#include <sysdep.h>
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#define VEC_SIZE 16
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#define VEC(i) xmm##i
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#define PREFETCHNT prefetchnta
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#define VMOVNT movntdq
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/* Use movups and movaps for smaller code sizes. */
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#define VMOVU movups
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#define VMOVA movaps
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#define MOV_SIZE 3
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#define SECTION(p) p
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#ifdef USE_MULTIARCH
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# if !IS_IN (libc)
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# define MEMCPY_SYMBOL(p,s) memcpy
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# endif
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#else
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# if defined SHARED && IS_IN (libc)
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# define MEMCPY_SYMBOL(p,s) __memcpy
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# else
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# define MEMCPY_SYMBOL(p,s) memcpy
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# endif
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#endif
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#if !defined USE_MULTIARCH || !IS_IN (libc)
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# define MEMPCPY_SYMBOL(p,s) __mempcpy
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#endif
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#ifndef MEMMOVE_SYMBOL
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# define MEMMOVE_CHK_SYMBOL(p,s) p
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# define MEMMOVE_SYMBOL(p,s) memmove
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#endif
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#include "multiarch/memmove-vec-unaligned-erms.S"
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#ifndef USE_MULTIARCH
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libc_hidden_builtin_def (memmove)
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# if defined SHARED && IS_IN (libc)
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strong_alias (memmove, __memcpy)
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libc_hidden_ver (memmove, memcpy)
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# endif
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libc_hidden_def (__mempcpy)
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weak_alias (__mempcpy, mempcpy)
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libc_hidden_builtin_def (mempcpy)
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# if defined SHARED && IS_IN (libc)
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# undef memcpy
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# include <shlib-compat.h>
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versioned_symbol (libc, __memcpy, memcpy, GLIBC_2_14);
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# if SHLIB_COMPAT (libc, GLIBC_2_2_5, GLIBC_2_14)
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compat_symbol (libc, memmove, memcpy, GLIBC_2_2_5);
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# endif
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# endif
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#endif
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