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glibc/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S
noah 1a8605b6cd x86: Update large memcpy case in memmove-vec-unaligned-erms.S 
No Bug. This commit updates the large memcpy case (no overlap). The
update is to perform memcpy on either 2 or 4 contiguous pages at
once. This 1) helps to alleviate the affects of false memory aliasing
when destination and source have a close 4k alignment and 2) In most
cases and for most DRAM units is a modestly more efficient access
pattern. These changes are a clear performance improvement for
VEC_SIZE =16/32, though more ambiguous for VEC_SIZE=64. test-memcpy,
test-memccpy, test-mempcpy, test-memmove, and tst-memmove-overflow all
pass.

Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com>
2021-04-16 10:06:56 -07:00

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/* memmove/memcpy/mempcpy with unaligned load/store and rep movsb
Copyright (C) 2016-2021 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/>. */
/* memmove/memcpy/mempcpy is implemented as:
1. Use overlapping load and store to avoid branch.
2. Load all sources into registers and store them together to avoid
possible address overlap between source and destination.
3. If size is 8 * VEC_SIZE or less, load all sources into registers
and store them together.
4. If address of destination > address of source, backward copy
4 * VEC_SIZE at a time with unaligned load and aligned store.
Load the first 4 * VEC and last VEC before the loop and store
them after the loop to support overlapping addresses.
5. Otherwise, forward copy 4 * VEC_SIZE at a time with unaligned
load and aligned store. Load the last 4 * VEC and first VEC
before the loop and store them after the loop to support
overlapping addresses.
6. On machines with ERMS feature, if size greater than equal or to
__x86_rep_movsb_threshold and less than
__x86_rep_movsb_stop_threshold, then REP MOVSB will be used.
7. If size >= __x86_shared_non_temporal_threshold and there is no
overlap between destination and source, use non-temporal store
instead of aligned store copying from either 2 or 4 pages at
once.
8. For point 7) if size < 16 * __x86_shared_non_temporal_threshold
and source and destination do not page alias, copy from 2 pages
at once using non-temporal stores. Page aliasing in this case is
considered true if destination's page alignment - sources' page
alignment is less than 8 * VEC_SIZE.
9. If size >= 16 * __x86_shared_non_temporal_threshold or source
and destination do page alias copy from 4 pages at once using
non-temporal stores. */
#include <sysdep.h>
#ifndef MEMCPY_SYMBOL
# define MEMCPY_SYMBOL(p,s) MEMMOVE_SYMBOL(p, s)
#endif
#ifndef MEMPCPY_SYMBOL
# define MEMPCPY_SYMBOL(p,s) MEMMOVE_SYMBOL(p, s)
#endif
#ifndef MEMMOVE_CHK_SYMBOL
# define MEMMOVE_CHK_SYMBOL(p,s) MEMMOVE_SYMBOL(p, s)
#endif
#ifndef XMM0
# define XMM0 xmm0
#endif
#ifndef YMM0
# define YMM0 ymm0
#endif
#ifndef VZEROUPPER
# if VEC_SIZE > 16
# define VZEROUPPER vzeroupper
# else
# define VZEROUPPER
# endif
#endif
#ifndef PAGE_SIZE
# define PAGE_SIZE 4096
#endif
#if PAGE_SIZE != 4096
# error Unsupported PAGE_SIZE
#endif
#ifndef LOG_PAGE_SIZE
# define LOG_PAGE_SIZE 12
#endif
#if PAGE_SIZE != (1 << LOG_PAGE_SIZE)
# error Invalid LOG_PAGE_SIZE
#endif
/* Byte per page for large_memcpy inner loop. */
#if VEC_SIZE == 64
# define LARGE_LOAD_SIZE (VEC_SIZE * 2)
#else
# define LARGE_LOAD_SIZE (VEC_SIZE * 4)
#endif
/* Amount to shift rdx by to compare for memcpy_large_4x. */
#ifndef LOG_4X_MEMCPY_THRESH
# define LOG_4X_MEMCPY_THRESH 4
#endif
/* Avoid short distance rep movsb only with non-SSE vector. */
#ifndef AVOID_SHORT_DISTANCE_REP_MOVSB
# define AVOID_SHORT_DISTANCE_REP_MOVSB (VEC_SIZE > 16)
#else
# define AVOID_SHORT_DISTANCE_REP_MOVSB 0
#endif
#ifndef PREFETCH
# define PREFETCH(addr) prefetcht0 addr
#endif
/* Assume 64-byte prefetch size. */
#ifndef PREFETCH_SIZE
# define PREFETCH_SIZE 64
#endif
#define PREFETCHED_LOAD_SIZE (VEC_SIZE * 4)
#if PREFETCH_SIZE == 64
# if PREFETCHED_LOAD_SIZE == PREFETCH_SIZE
# define PREFETCH_ONE_SET(dir, base, offset) \
PREFETCH ((offset)base)
# elif PREFETCHED_LOAD_SIZE == 2 * PREFETCH_SIZE
# define PREFETCH_ONE_SET(dir, base, offset) \
PREFETCH ((offset)base); \
PREFETCH ((offset + dir * PREFETCH_SIZE)base)
# elif PREFETCHED_LOAD_SIZE == 4 * PREFETCH_SIZE
# define PREFETCH_ONE_SET(dir, base, offset) \
PREFETCH ((offset)base); \
PREFETCH ((offset + dir * PREFETCH_SIZE)base); \
PREFETCH ((offset + dir * PREFETCH_SIZE * 2)base); \
PREFETCH ((offset + dir * PREFETCH_SIZE * 3)base)
# else
# error Unsupported PREFETCHED_LOAD_SIZE!
# endif
#else
# error Unsupported PREFETCH_SIZE!
#endif
#if LARGE_LOAD_SIZE == (VEC_SIZE * 2)
# define LOAD_ONE_SET(base, offset, vec0, vec1, ...) \
VMOVU (offset)base, vec0; \
VMOVU ((offset) + VEC_SIZE)base, vec1;
# define STORE_ONE_SET(base, offset, vec0, vec1, ...) \
VMOVNT vec0, (offset)base; \
VMOVNT vec1, ((offset) + VEC_SIZE)base;
#elif LARGE_LOAD_SIZE == (VEC_SIZE * 4)
# define LOAD_ONE_SET(base, offset, vec0, vec1, vec2, vec3) \
VMOVU (offset)base, vec0; \
VMOVU ((offset) + VEC_SIZE)base, vec1; \
VMOVU ((offset) + VEC_SIZE * 2)base, vec2; \
VMOVU ((offset) + VEC_SIZE * 3)base, vec3;
# define STORE_ONE_SET(base, offset, vec0, vec1, vec2, vec3) \
VMOVNT vec0, (offset)base; \
VMOVNT vec1, ((offset) + VEC_SIZE)base; \
VMOVNT vec2, ((offset) + VEC_SIZE * 2)base; \
VMOVNT vec3, ((offset) + VEC_SIZE * 3)base;
#else
# error Invalid LARGE_LOAD_SIZE
#endif
#ifndef SECTION
# error SECTION is not defined!
#endif
.section SECTION(.text),"ax",@progbits
#if defined SHARED && IS_IN (libc)
ENTRY (MEMMOVE_CHK_SYMBOL (__mempcpy_chk, unaligned))
cmp %RDX_LP, %RCX_LP
jb HIDDEN_JUMPTARGET (__chk_fail)
END (MEMMOVE_CHK_SYMBOL (__mempcpy_chk, unaligned))
#endif
ENTRY (MEMPCPY_SYMBOL (__mempcpy, unaligned))
mov %RDI_LP, %RAX_LP
add %RDX_LP, %RAX_LP
jmp L(start)
END (MEMPCPY_SYMBOL (__mempcpy, unaligned))
#if defined SHARED && IS_IN (libc)
ENTRY (MEMMOVE_CHK_SYMBOL (__memmove_chk, unaligned))
cmp %RDX_LP, %RCX_LP
jb HIDDEN_JUMPTARGET (__chk_fail)
END (MEMMOVE_CHK_SYMBOL (__memmove_chk, unaligned))
#endif
ENTRY (MEMMOVE_SYMBOL (__memmove, unaligned))
movq %rdi, %rax
L(start):
# ifdef __ILP32__
/* Clear the upper 32 bits. */
movl %edx, %edx
# endif
cmp $VEC_SIZE, %RDX_LP
jb L(less_vec)
cmp $(VEC_SIZE * 2), %RDX_LP
ja L(more_2x_vec)
#if !defined USE_MULTIARCH || !IS_IN (libc)
L(last_2x_vec):
#endif
/* From VEC and to 2 * VEC. No branch when size == VEC_SIZE. */
VMOVU (%rsi), %VEC(0)
VMOVU -VEC_SIZE(%rsi,%rdx), %VEC(1)
VMOVU %VEC(0), (%rdi)
VMOVU %VEC(1), -VEC_SIZE(%rdi,%rdx)
#if !defined USE_MULTIARCH || !IS_IN (libc)
L(nop):
ret
#else
VZEROUPPER_RETURN
#endif
#if defined USE_MULTIARCH && IS_IN (libc)
END (MEMMOVE_SYMBOL (__memmove, unaligned))
# if VEC_SIZE == 16
ENTRY (__mempcpy_chk_erms)
cmp %RDX_LP, %RCX_LP
jb HIDDEN_JUMPTARGET (__chk_fail)
END (__mempcpy_chk_erms)
/* Only used to measure performance of REP MOVSB. */
ENTRY (__mempcpy_erms)
mov %RDI_LP, %RAX_LP
/* Skip zero length. */
test %RDX_LP, %RDX_LP
jz 2f
add %RDX_LP, %RAX_LP
jmp L(start_movsb)
END (__mempcpy_erms)
ENTRY (__memmove_chk_erms)
cmp %RDX_LP, %RCX_LP
jb HIDDEN_JUMPTARGET (__chk_fail)
END (__memmove_chk_erms)
ENTRY (__memmove_erms)
movq %rdi, %rax
/* Skip zero length. */
test %RDX_LP, %RDX_LP
jz 2f
L(start_movsb):
mov %RDX_LP, %RCX_LP
cmp %RSI_LP, %RDI_LP
jb 1f
/* Source == destination is less common. */
je 2f
lea (%rsi,%rcx), %RDX_LP
cmp %RDX_LP, %RDI_LP
jb L(movsb_backward)
1:
rep movsb
2:
ret
L(movsb_backward):
leaq -1(%rdi,%rcx), %rdi
leaq -1(%rsi,%rcx), %rsi
std
rep movsb
cld
ret
END (__memmove_erms)
strong_alias (__memmove_erms, __memcpy_erms)
strong_alias (__memmove_chk_erms, __memcpy_chk_erms)
# endif
# ifdef SHARED
ENTRY (MEMMOVE_CHK_SYMBOL (__mempcpy_chk, unaligned_erms))
cmp %RDX_LP, %RCX_LP
jb HIDDEN_JUMPTARGET (__chk_fail)
END (MEMMOVE_CHK_SYMBOL (__mempcpy_chk, unaligned_erms))
# endif
ENTRY (MEMMOVE_SYMBOL (__mempcpy, unaligned_erms))
mov %RDI_LP, %RAX_LP
add %RDX_LP, %RAX_LP
jmp L(start_erms)
END (MEMMOVE_SYMBOL (__mempcpy, unaligned_erms))
# ifdef SHARED
ENTRY (MEMMOVE_CHK_SYMBOL (__memmove_chk, unaligned_erms))
cmp %RDX_LP, %RCX_LP
jb HIDDEN_JUMPTARGET (__chk_fail)
END (MEMMOVE_CHK_SYMBOL (__memmove_chk, unaligned_erms))
# endif
ENTRY (MEMMOVE_SYMBOL (__memmove, unaligned_erms))
movq %rdi, %rax
L(start_erms):
# ifdef __ILP32__
/* Clear the upper 32 bits. */
movl %edx, %edx
# endif
cmp $VEC_SIZE, %RDX_LP
jb L(less_vec)
cmp $(VEC_SIZE * 2), %RDX_LP
ja L(movsb_more_2x_vec)
L(last_2x_vec):
/* From VEC and to 2 * VEC. No branch when size == VEC_SIZE. */
VMOVU (%rsi), %VEC(0)
VMOVU -VEC_SIZE(%rsi,%rdx), %VEC(1)
VMOVU %VEC(0), (%rdi)
VMOVU %VEC(1), -VEC_SIZE(%rdi,%rdx)
L(return):
#if VEC_SIZE > 16
ZERO_UPPER_VEC_REGISTERS_RETURN
#else
ret
#endif
L(movsb):
cmp __x86_rep_movsb_stop_threshold(%rip), %RDX_LP
jae L(more_8x_vec)
cmpq %rsi, %rdi
jb 1f
/* Source == destination is less common. */
je L(nop)
leaq (%rsi,%rdx), %r9
cmpq %r9, %rdi
/* Avoid slow backward REP MOVSB. */
jb L(more_8x_vec_backward)
# if AVOID_SHORT_DISTANCE_REP_MOVSB
movq %rdi, %rcx
subq %rsi, %rcx
jmp 2f
# endif
1:
# if AVOID_SHORT_DISTANCE_REP_MOVSB
movq %rsi, %rcx
subq %rdi, %rcx
2:
/* Avoid "rep movsb" if RCX, the distance between source and destination,
is N*4GB + [1..63] with N >= 0. */
cmpl $63, %ecx
jbe L(more_2x_vec) /* Avoid "rep movsb" if ECX <= 63. */
# endif
mov %RDX_LP, %RCX_LP
rep movsb
L(nop):
ret
#endif
L(less_vec):
/* Less than 1 VEC. */
#if VEC_SIZE != 16 && VEC_SIZE != 32 && VEC_SIZE != 64
# error Unsupported VEC_SIZE!
#endif
#if VEC_SIZE > 32
cmpb $32, %dl
jae L(between_32_63)
#endif
#if VEC_SIZE > 16
cmpb $16, %dl
jae L(between_16_31)
#endif
cmpb $8, %dl
jae L(between_8_15)
cmpb $4, %dl
jae L(between_4_7)
cmpb $1, %dl
ja L(between_2_3)
jb 1f
movzbl (%rsi), %ecx
movb %cl, (%rdi)
1:
ret
#if VEC_SIZE > 32
L(between_32_63):
/* From 32 to 63. No branch when size == 32. */
VMOVU (%rsi), %YMM0
VMOVU -32(%rsi,%rdx), %YMM1
VMOVU %YMM0, (%rdi)
VMOVU %YMM1, -32(%rdi,%rdx)
VZEROUPPER_RETURN
#endif
#if VEC_SIZE > 16
/* From 16 to 31. No branch when size == 16. */
L(between_16_31):
VMOVU (%rsi), %XMM0
VMOVU -16(%rsi,%rdx), %XMM1
VMOVU %XMM0, (%rdi)
VMOVU %XMM1, -16(%rdi,%rdx)
VZEROUPPER_RETURN
#endif
L(between_8_15):
/* From 8 to 15. No branch when size == 8. */
movq -8(%rsi,%rdx), %rcx
movq (%rsi), %rsi
movq %rcx, -8(%rdi,%rdx)
movq %rsi, (%rdi)
ret
L(between_4_7):
/* From 4 to 7. No branch when size == 4. */
movl -4(%rsi,%rdx), %ecx
movl (%rsi), %esi
movl %ecx, -4(%rdi,%rdx)
movl %esi, (%rdi)
ret
L(between_2_3):
/* From 2 to 3. No branch when size == 2. */
movzwl -2(%rsi,%rdx), %ecx
movzwl (%rsi), %esi
movw %cx, -2(%rdi,%rdx)
movw %si, (%rdi)
ret
#if defined USE_MULTIARCH && IS_IN (libc)
L(movsb_more_2x_vec):
cmp __x86_rep_movsb_threshold(%rip), %RDX_LP
ja L(movsb)
#endif
L(more_2x_vec):
/* More than 2 * VEC and there may be overlap between destination
and source. */
cmpq $(VEC_SIZE * 8), %rdx
ja L(more_8x_vec)
cmpq $(VEC_SIZE * 4), %rdx
jb L(last_4x_vec)
/* Copy from 4 * VEC to 8 * VEC, inclusively. */
VMOVU (%rsi), %VEC(0)
VMOVU VEC_SIZE(%rsi), %VEC(1)
VMOVU (VEC_SIZE * 2)(%rsi), %VEC(2)
VMOVU (VEC_SIZE * 3)(%rsi), %VEC(3)
VMOVU -VEC_SIZE(%rsi,%rdx), %VEC(4)
VMOVU -(VEC_SIZE * 2)(%rsi,%rdx), %VEC(5)
VMOVU -(VEC_SIZE * 3)(%rsi,%rdx), %VEC(6)
VMOVU -(VEC_SIZE * 4)(%rsi,%rdx), %VEC(7)
VMOVU %VEC(0), (%rdi)
VMOVU %VEC(1), VEC_SIZE(%rdi)
VMOVU %VEC(2), (VEC_SIZE * 2)(%rdi)
VMOVU %VEC(3), (VEC_SIZE * 3)(%rdi)
VMOVU %VEC(4), -VEC_SIZE(%rdi,%rdx)
VMOVU %VEC(5), -(VEC_SIZE * 2)(%rdi,%rdx)
VMOVU %VEC(6), -(VEC_SIZE * 3)(%rdi,%rdx)
VMOVU %VEC(7), -(VEC_SIZE * 4)(%rdi,%rdx)
VZEROUPPER_RETURN
L(last_4x_vec):
/* Copy from 2 * VEC to 4 * VEC. */
VMOVU (%rsi), %VEC(0)
VMOVU VEC_SIZE(%rsi), %VEC(1)
VMOVU -VEC_SIZE(%rsi,%rdx), %VEC(2)
VMOVU -(VEC_SIZE * 2)(%rsi,%rdx), %VEC(3)
VMOVU %VEC(0), (%rdi)
VMOVU %VEC(1), VEC_SIZE(%rdi)
VMOVU %VEC(2), -VEC_SIZE(%rdi,%rdx)
VMOVU %VEC(3), -(VEC_SIZE * 2)(%rdi,%rdx)
VZEROUPPER_RETURN
L(more_8x_vec):
/* Check if non-temporal move candidate. */
#if (defined USE_MULTIARCH || VEC_SIZE == 16) && IS_IN (libc)
/* Check non-temporal store threshold. */
cmp __x86_shared_non_temporal_threshold(%rip), %RDX_LP
ja L(large_memcpy_2x)
#endif
/* Entry if rdx is greater than non-temporal threshold but there
is overlap. */
L(more_8x_vec_check):
cmpq %rsi, %rdi
ja L(more_8x_vec_backward)
/* Source == destination is less common. */
je L(nop)
/* Load the first VEC and last 4 * VEC to support overlapping
addresses. */
VMOVU (%rsi), %VEC(4)
VMOVU -VEC_SIZE(%rsi, %rdx), %VEC(5)
VMOVU -(VEC_SIZE * 2)(%rsi, %rdx), %VEC(6)
VMOVU -(VEC_SIZE * 3)(%rsi, %rdx), %VEC(7)
VMOVU -(VEC_SIZE * 4)(%rsi, %rdx), %VEC(8)
/* Save start and stop of the destination buffer. */
movq %rdi, %r11
leaq -VEC_SIZE(%rdi, %rdx), %rcx
/* Align destination for aligned stores in the loop. Compute
how much destination is misaligned. */
movq %rdi, %r8
andq $(VEC_SIZE - 1), %r8
/* Get the negative of offset for alignment. */
subq $VEC_SIZE, %r8
/* Adjust source. */
subq %r8, %rsi
/* Adjust destination which should be aligned now. */
subq %r8, %rdi
/* Adjust length. */
addq %r8, %rdx
.p2align 4
L(loop_4x_vec_forward):
/* Copy 4 * VEC a time forward. */
VMOVU (%rsi), %VEC(0)
VMOVU VEC_SIZE(%rsi), %VEC(1)
VMOVU (VEC_SIZE * 2)(%rsi), %VEC(2)
VMOVU (VEC_SIZE * 3)(%rsi), %VEC(3)
subq $-(VEC_SIZE * 4), %rsi
addq $-(VEC_SIZE * 4), %rdx
VMOVA %VEC(0), (%rdi)
VMOVA %VEC(1), VEC_SIZE(%rdi)
VMOVA %VEC(2), (VEC_SIZE * 2)(%rdi)
VMOVA %VEC(3), (VEC_SIZE * 3)(%rdi)
subq $-(VEC_SIZE * 4), %rdi
cmpq $(VEC_SIZE * 4), %rdx
ja L(loop_4x_vec_forward)
/* Store the last 4 * VEC. */
VMOVU %VEC(5), (%rcx)
VMOVU %VEC(6), -VEC_SIZE(%rcx)
VMOVU %VEC(7), -(VEC_SIZE * 2)(%rcx)
VMOVU %VEC(8), -(VEC_SIZE * 3)(%rcx)
/* Store the first VEC. */
VMOVU %VEC(4), (%r11)
VZEROUPPER_RETURN
L(more_8x_vec_backward):
/* Load the first 4 * VEC and last VEC to support overlapping
addresses. */
VMOVU (%rsi), %VEC(4)
VMOVU VEC_SIZE(%rsi), %VEC(5)
VMOVU (VEC_SIZE * 2)(%rsi), %VEC(6)
VMOVU (VEC_SIZE * 3)(%rsi), %VEC(7)
VMOVU -VEC_SIZE(%rsi,%rdx), %VEC(8)
/* Save stop of the destination buffer. */
leaq -VEC_SIZE(%rdi, %rdx), %r11
/* Align destination end for aligned stores in the loop. Compute
how much destination end is misaligned. */
leaq -VEC_SIZE(%rsi, %rdx), %rcx
movq %r11, %r9
movq %r11, %r8
andq $(VEC_SIZE - 1), %r8
/* Adjust source. */
subq %r8, %rcx
/* Adjust the end of destination which should be aligned now. */
subq %r8, %r9
/* Adjust length. */
subq %r8, %rdx
.p2align 4
L(loop_4x_vec_backward):
/* Copy 4 * VEC a time backward. */
VMOVU (%rcx), %VEC(0)
VMOVU -VEC_SIZE(%rcx), %VEC(1)
VMOVU -(VEC_SIZE * 2)(%rcx), %VEC(2)
VMOVU -(VEC_SIZE * 3)(%rcx), %VEC(3)
addq $-(VEC_SIZE * 4), %rcx
addq $-(VEC_SIZE * 4), %rdx
VMOVA %VEC(0), (%r9)
VMOVA %VEC(1), -VEC_SIZE(%r9)
VMOVA %VEC(2), -(VEC_SIZE * 2)(%r9)
VMOVA %VEC(3), -(VEC_SIZE * 3)(%r9)
addq $-(VEC_SIZE * 4), %r9
cmpq $(VEC_SIZE * 4), %rdx
ja L(loop_4x_vec_backward)
/* Store the first 4 * VEC. */
VMOVU %VEC(4), (%rdi)
VMOVU %VEC(5), VEC_SIZE(%rdi)
VMOVU %VEC(6), (VEC_SIZE * 2)(%rdi)
VMOVU %VEC(7), (VEC_SIZE * 3)(%rdi)
/* Store the last VEC. */
VMOVU %VEC(8), (%r11)
VZEROUPPER_RETURN
#if (defined USE_MULTIARCH || VEC_SIZE == 16) && IS_IN (libc)
.p2align 4
L(large_memcpy_2x):
/* Compute absolute value of difference between source and
destination. */
movq %rdi, %r9
subq %rsi, %r9
movq %r9, %r8
leaq -1(%r9), %rcx
sarq $63, %r8
xorq %r8, %r9
subq %r8, %r9
/* Don't use non-temporal store if there is overlap between
destination and source since destination may be in cache when
source is loaded. */
cmpq %r9, %rdx
ja L(more_8x_vec_check)
/* Cache align destination. First store the first 64 bytes then
adjust alignments. */
VMOVU (%rsi), %VEC(8)
#if VEC_SIZE < 64
VMOVU VEC_SIZE(%rsi), %VEC(9)
#if VEC_SIZE < 32
VMOVU (VEC_SIZE * 2)(%rsi), %VEC(10)
VMOVU (VEC_SIZE * 3)(%rsi), %VEC(11)
#endif
#endif
VMOVU %VEC(8), (%rdi)
#if VEC_SIZE < 64
VMOVU %VEC(9), VEC_SIZE(%rdi)
#if VEC_SIZE < 32
VMOVU %VEC(10), (VEC_SIZE * 2)(%rdi)
VMOVU %VEC(11), (VEC_SIZE * 3)(%rdi)
#endif
#endif
/* Adjust source, destination, and size. */
movq %rdi, %r8
andq $63, %r8
/* Get the negative of offset for alignment. */
subq $64, %r8
/* Adjust source. */
subq %r8, %rsi
/* Adjust destination which should be aligned now. */
subq %r8, %rdi
/* Adjust length. */
addq %r8, %rdx
/* Test if source and destination addresses will alias. If they do
the larger pipeline in large_memcpy_4x alleviated the
performance drop. */
testl $(PAGE_SIZE - VEC_SIZE * 8), %ecx
jz L(large_memcpy_4x)
movq %rdx, %r10
shrq $LOG_4X_MEMCPY_THRESH, %r10
cmp __x86_shared_non_temporal_threshold(%rip), %r10
jae L(large_memcpy_4x)
/* edx will store remainder size for copying tail. */
andl $(PAGE_SIZE * 2 - 1), %edx
/* r10 stores outer loop counter. */
shrq $((LOG_PAGE_SIZE + 1) - LOG_4X_MEMCPY_THRESH), %r10
/* Copy 4x VEC at a time from 2 pages. */
.p2align 4
L(loop_large_memcpy_2x_outer):
/* ecx stores inner loop counter. */
movl $(PAGE_SIZE / LARGE_LOAD_SIZE), %ecx
L(loop_large_memcpy_2x_inner):
PREFETCH_ONE_SET(1, (%rsi), PREFETCHED_LOAD_SIZE)
PREFETCH_ONE_SET(1, (%rsi), PREFETCHED_LOAD_SIZE * 2)
PREFETCH_ONE_SET(1, (%rsi), PAGE_SIZE + PREFETCHED_LOAD_SIZE)
PREFETCH_ONE_SET(1, (%rsi), PAGE_SIZE + PREFETCHED_LOAD_SIZE * 2)
/* Load vectors from rsi. */
LOAD_ONE_SET((%rsi), 0, %VEC(0), %VEC(1), %VEC(2), %VEC(3))
LOAD_ONE_SET((%rsi), PAGE_SIZE, %VEC(4), %VEC(5), %VEC(6), %VEC(7))
subq $-LARGE_LOAD_SIZE, %rsi
/* Non-temporal store vectors to rdi. */
STORE_ONE_SET((%rdi), 0, %VEC(0), %VEC(1), %VEC(2), %VEC(3))
STORE_ONE_SET((%rdi), PAGE_SIZE, %VEC(4), %VEC(5), %VEC(6), %VEC(7))
subq $-LARGE_LOAD_SIZE, %rdi
decl %ecx
jnz L(loop_large_memcpy_2x_inner)
addq $PAGE_SIZE, %rdi
addq $PAGE_SIZE, %rsi
decq %r10
jne L(loop_large_memcpy_2x_outer)
sfence
/* Check if only last 4 loads are needed. */
cmpl $(VEC_SIZE * 4), %edx
jbe L(large_memcpy_2x_end)
/* Handle the last 2 * PAGE_SIZE bytes. */
L(loop_large_memcpy_2x_tail):
/* Copy 4 * VEC a time forward with non-temporal stores. */
PREFETCH_ONE_SET (1, (%rsi), PREFETCHED_LOAD_SIZE)
PREFETCH_ONE_SET (1, (%rdi), PREFETCHED_LOAD_SIZE)
VMOVU (%rsi), %VEC(0)
VMOVU VEC_SIZE(%rsi), %VEC(1)
VMOVU (VEC_SIZE * 2)(%rsi), %VEC(2)
VMOVU (VEC_SIZE * 3)(%rsi), %VEC(3)
subq $-(VEC_SIZE * 4), %rsi
addl $-(VEC_SIZE * 4), %edx
VMOVA %VEC(0), (%rdi)
VMOVA %VEC(1), VEC_SIZE(%rdi)
VMOVA %VEC(2), (VEC_SIZE * 2)(%rdi)
VMOVA %VEC(3), (VEC_SIZE * 3)(%rdi)
subq $-(VEC_SIZE * 4), %rdi
cmpl $(VEC_SIZE * 4), %edx
ja L(loop_large_memcpy_2x_tail)
L(large_memcpy_2x_end):
/* Store the last 4 * VEC. */
VMOVU -(VEC_SIZE * 4)(%rsi, %rdx), %VEC(0)
VMOVU -(VEC_SIZE * 3)(%rsi, %rdx), %VEC(1)
VMOVU -(VEC_SIZE * 2)(%rsi, %rdx), %VEC(2)
VMOVU -VEC_SIZE(%rsi, %rdx), %VEC(3)
VMOVU %VEC(0), -(VEC_SIZE * 4)(%rdi, %rdx)
VMOVU %VEC(1), -(VEC_SIZE * 3)(%rdi, %rdx)
VMOVU %VEC(2), -(VEC_SIZE * 2)(%rdi, %rdx)
VMOVU %VEC(3), -VEC_SIZE(%rdi, %rdx)
VZEROUPPER_RETURN
.p2align 4
L(large_memcpy_4x):
movq %rdx, %r10
/* edx will store remainder size for copying tail. */
andl $(PAGE_SIZE * 4 - 1), %edx
/* r10 stores outer loop counter. */
shrq $(LOG_PAGE_SIZE + 2), %r10
/* Copy 4x VEC at a time from 4 pages. */
.p2align 4
L(loop_large_memcpy_4x_outer):
/* ecx stores inner loop counter. */
movl $(PAGE_SIZE / LARGE_LOAD_SIZE), %ecx
L(loop_large_memcpy_4x_inner):
/* Only one prefetch set per page as doing 4 pages give more time
for prefetcher to keep up. */
PREFETCH_ONE_SET(1, (%rsi), PREFETCHED_LOAD_SIZE)
PREFETCH_ONE_SET(1, (%rsi), PAGE_SIZE + PREFETCHED_LOAD_SIZE)
PREFETCH_ONE_SET(1, (%rsi), PAGE_SIZE * 2 + PREFETCHED_LOAD_SIZE)
PREFETCH_ONE_SET(1, (%rsi), PAGE_SIZE * 3 + PREFETCHED_LOAD_SIZE)
/* Load vectors from rsi. */
LOAD_ONE_SET((%rsi), 0, %VEC(0), %VEC(1), %VEC(2), %VEC(3))
LOAD_ONE_SET((%rsi), PAGE_SIZE, %VEC(4), %VEC(5), %VEC(6), %VEC(7))
LOAD_ONE_SET((%rsi), PAGE_SIZE * 2, %VEC(8), %VEC(9), %VEC(10), %VEC(11))
LOAD_ONE_SET((%rsi), PAGE_SIZE * 3, %VEC(12), %VEC(13), %VEC(14), %VEC(15))
subq $-LARGE_LOAD_SIZE, %rsi
/* Non-temporal store vectors to rdi. */
STORE_ONE_SET((%rdi), 0, %VEC(0), %VEC(1), %VEC(2), %VEC(3))
STORE_ONE_SET((%rdi), PAGE_SIZE, %VEC(4), %VEC(5), %VEC(6), %VEC(7))
STORE_ONE_SET((%rdi), PAGE_SIZE * 2, %VEC(8), %VEC(9), %VEC(10), %VEC(11))
STORE_ONE_SET((%rdi), PAGE_SIZE * 3, %VEC(12), %VEC(13), %VEC(14), %VEC(15))
subq $-LARGE_LOAD_SIZE, %rdi
decl %ecx
jnz L(loop_large_memcpy_4x_inner)
addq $(PAGE_SIZE * 3), %rdi
addq $(PAGE_SIZE * 3), %rsi
decq %r10
jne L(loop_large_memcpy_4x_outer)
sfence
/* Check if only last 4 loads are needed. */
cmpl $(VEC_SIZE * 4), %edx
jbe L(large_memcpy_4x_end)
/* Handle the last 4 * PAGE_SIZE bytes. */
L(loop_large_memcpy_4x_tail):
/* Copy 4 * VEC a time forward with non-temporal stores. */
PREFETCH_ONE_SET (1, (%rsi), PREFETCHED_LOAD_SIZE)
PREFETCH_ONE_SET (1, (%rdi), PREFETCHED_LOAD_SIZE)
VMOVU (%rsi), %VEC(0)
VMOVU VEC_SIZE(%rsi), %VEC(1)
VMOVU (VEC_SIZE * 2)(%rsi), %VEC(2)
VMOVU (VEC_SIZE * 3)(%rsi), %VEC(3)
subq $-(VEC_SIZE * 4), %rsi
addl $-(VEC_SIZE * 4), %edx
VMOVA %VEC(0), (%rdi)
VMOVA %VEC(1), VEC_SIZE(%rdi)
VMOVA %VEC(2), (VEC_SIZE * 2)(%rdi)
VMOVA %VEC(3), (VEC_SIZE * 3)(%rdi)
subq $-(VEC_SIZE * 4), %rdi
cmpl $(VEC_SIZE * 4), %edx
ja L(loop_large_memcpy_4x_tail)
L(large_memcpy_4x_end):
/* Store the last 4 * VEC. */
VMOVU -(VEC_SIZE * 4)(%rsi, %rdx), %VEC(0)
VMOVU -(VEC_SIZE * 3)(%rsi, %rdx), %VEC(1)
VMOVU -(VEC_SIZE * 2)(%rsi, %rdx), %VEC(2)
VMOVU -VEC_SIZE(%rsi, %rdx), %VEC(3)
VMOVU %VEC(0), -(VEC_SIZE * 4)(%rdi, %rdx)
VMOVU %VEC(1), -(VEC_SIZE * 3)(%rdi, %rdx)
VMOVU %VEC(2), -(VEC_SIZE * 2)(%rdi, %rdx)
VMOVU %VEC(3), -VEC_SIZE(%rdi, %rdx)
VZEROUPPER_RETURN
#endif
END (MEMMOVE_SYMBOL (__memmove, unaligned_erms))
#if IS_IN (libc)
# ifdef USE_MULTIARCH
strong_alias (MEMMOVE_SYMBOL (__memmove, unaligned_erms),
MEMMOVE_SYMBOL (__memcpy, unaligned_erms))
# ifdef SHARED
strong_alias (MEMMOVE_SYMBOL (__memmove_chk, unaligned_erms),
MEMMOVE_SYMBOL (__memcpy_chk, unaligned_erms))
# endif
# endif
# ifdef SHARED
strong_alias (MEMMOVE_CHK_SYMBOL (__memmove_chk, unaligned),
MEMMOVE_CHK_SYMBOL (__memcpy_chk, unaligned))
# endif
#endif
strong_alias (MEMMOVE_SYMBOL (__memmove, unaligned),
MEMCPY_SYMBOL (__memcpy, unaligned))
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