mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-21 04:31:04 +08:00
2d48b41c8f
We add new memcpy version that uses unaligned loads which are fast on modern processors. This allows second improvement which is avoiding computed jump which is relatively expensive operation. Tests available here: http://kam.mff.cuni.cz/~ondra/memcpy_profile_result27_04_13.tar.bz2
176 lines
3.5 KiB
ArmAsm
176 lines
3.5 KiB
ArmAsm
/* memcpy with unaliged loads
|
|
Copyright (C) 2013 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
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <sysdep.h>
|
|
|
|
#include "asm-syntax.h"
|
|
|
|
#ifndef ALIGN
|
|
# define ALIGN(n) .p2align n
|
|
#endif
|
|
|
|
|
|
ENTRY(__memcpy_sse2_unaligned)
|
|
movq %rsi, %rax
|
|
leaq (%rdx,%rdx), %rcx
|
|
subq %rdi, %rax
|
|
subq %rdx, %rax
|
|
cmpq %rcx, %rax
|
|
jb L(overlapping)
|
|
cmpq $16, %rdx
|
|
jbe L(less_16)
|
|
movdqu (%rsi), %xmm8
|
|
cmpq $32, %rdx
|
|
movdqu %xmm8, (%rdi)
|
|
movdqu -16(%rsi,%rdx), %xmm8
|
|
movdqu %xmm8, -16(%rdi,%rdx)
|
|
ja .L31
|
|
L(return):
|
|
movq %rdi, %rax
|
|
ret
|
|
.p2align 4,,10
|
|
ALIGN(4)
|
|
.L31:
|
|
movdqu 16(%rsi), %xmm8
|
|
cmpq $64, %rdx
|
|
movdqu %xmm8, 16(%rdi)
|
|
movdqu -32(%rsi,%rdx), %xmm8
|
|
movdqu %xmm8, -32(%rdi,%rdx)
|
|
jbe L(return)
|
|
movdqu 32(%rsi), %xmm8
|
|
cmpq $128, %rdx
|
|
movdqu %xmm8, 32(%rdi)
|
|
movdqu -48(%rsi,%rdx), %xmm8
|
|
movdqu %xmm8, -48(%rdi,%rdx)
|
|
movdqu 48(%rsi), %xmm8
|
|
movdqu %xmm8, 48(%rdi)
|
|
movdqu -64(%rsi,%rdx), %xmm8
|
|
movdqu %xmm8, -64(%rdi,%rdx)
|
|
jbe L(return)
|
|
leaq 64(%rdi), %rcx
|
|
addq %rdi, %rdx
|
|
andq $-64, %rdx
|
|
andq $-64, %rcx
|
|
movq %rcx, %rax
|
|
subq %rdi, %rax
|
|
addq %rax, %rsi
|
|
cmpq %rdx, %rcx
|
|
je L(return)
|
|
movq %rsi, %r10
|
|
subq %rcx, %r10
|
|
leaq 16(%r10), %r9
|
|
leaq 32(%r10), %r8
|
|
leaq 48(%r10), %rax
|
|
.p2align 4,,10
|
|
ALIGN(4)
|
|
L(loop):
|
|
movdqu (%rcx,%r10), %xmm8
|
|
movdqa %xmm8, (%rcx)
|
|
movdqu (%rcx,%r9), %xmm8
|
|
movdqa %xmm8, 16(%rcx)
|
|
movdqu (%rcx,%r8), %xmm8
|
|
movdqa %xmm8, 32(%rcx)
|
|
movdqu (%rcx,%rax), %xmm8
|
|
movdqa %xmm8, 48(%rcx)
|
|
addq $64, %rcx
|
|
cmpq %rcx, %rdx
|
|
jne L(loop)
|
|
jmp L(return)
|
|
L(overlapping):
|
|
cmpq %rsi, %rdi
|
|
jae .L3
|
|
testq %rdx, %rdx
|
|
.p2align 4,,5
|
|
je L(return)
|
|
movq %rdx, %r9
|
|
leaq 16(%rsi), %rcx
|
|
leaq 16(%rdi), %r8
|
|
shrq $4, %r9
|
|
movq %r9, %rax
|
|
salq $4, %rax
|
|
cmpq %rcx, %rdi
|
|
setae %cl
|
|
cmpq %r8, %rsi
|
|
setae %r8b
|
|
orl %r8d, %ecx
|
|
cmpq $15, %rdx
|
|
seta %r8b
|
|
testb %r8b, %cl
|
|
je .L16
|
|
testq %rax, %rax
|
|
je .L16
|
|
xorl %ecx, %ecx
|
|
xorl %r8d, %r8d
|
|
.L7:
|
|
movdqu (%rsi,%rcx), %xmm8
|
|
addq $1, %r8
|
|
movdqu %xmm8, (%rdi,%rcx)
|
|
addq $16, %rcx
|
|
cmpq %r8, %r9
|
|
ja .L7
|
|
cmpq %rax, %rdx
|
|
je L(return)
|
|
.L21:
|
|
movzbl (%rsi,%rax), %ecx
|
|
movb %cl, (%rdi,%rax)
|
|
addq $1, %rax
|
|
cmpq %rax, %rdx
|
|
ja .L21
|
|
jmp L(return)
|
|
L(less_16):
|
|
testb $24, %dl
|
|
jne L(between_9_16)
|
|
testb $4, %dl
|
|
.p2align 4,,5
|
|
jne L(between_5_8)
|
|
testq %rdx, %rdx
|
|
.p2align 4,,2
|
|
je L(return)
|
|
movzbl (%rsi), %eax
|
|
testb $2, %dl
|
|
movb %al, (%rdi)
|
|
je L(return)
|
|
movzwl -2(%rsi,%rdx), %eax
|
|
movw %ax, -2(%rdi,%rdx)
|
|
jmp L(return)
|
|
.L3:
|
|
leaq -1(%rdx), %rax
|
|
.p2align 4,,10
|
|
ALIGN(4)
|
|
.L11:
|
|
movzbl (%rsi,%rax), %edx
|
|
movb %dl, (%rdi,%rax)
|
|
subq $1, %rax
|
|
jmp .L11
|
|
L(between_9_16):
|
|
movq (%rsi), %rax
|
|
movq %rax, (%rdi)
|
|
movq -8(%rsi,%rdx), %rax
|
|
movq %rax, -8(%rdi,%rdx)
|
|
jmp L(return)
|
|
.L16:
|
|
xorl %eax, %eax
|
|
jmp .L21
|
|
L(between_5_8):
|
|
movl (%rsi), %eax
|
|
movl %eax, (%rdi)
|
|
movl -4(%rsi,%rdx), %eax
|
|
movl %eax, -4(%rdi,%rdx)
|
|
jmp L(return)
|
|
END(__memcpy_sse2_unaligned)
|