1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
|
/* memset/bzero -- set memory area to CH/0
Optimized version for x86-64.
Copyright (C) 2002-2015 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>
.text
#if IS_IN (libc)
ENTRY(__bzero)
movq %rdi, %rax /* Set return value. */
movq %rsi, %rdx /* Set n. */
pxor %xmm0, %xmm0
jmp L(entry_from_bzero)
END(__bzero)
weak_alias (__bzero, bzero)
/* Like memset but takes additional parameter with return value. */
ENTRY(__memset_tail)
movq %rcx, %rax /* Set return value. */
movd %esi, %xmm0
punpcklbw %xmm0, %xmm0
punpcklwd %xmm0, %xmm0
pshufd $0, %xmm0, %xmm0
jmp L(entry_from_bzero)
END(__memset_tail)
#endif
#if defined PIC && IS_IN (libc)
ENTRY_CHK (__memset_chk)
cmpq %rdx, %rcx
jb HIDDEN_JUMPTARGET (__chk_fail)
END_CHK (__memset_chk)
#endif
ENTRY (memset)
movd %esi, %xmm0
movq %rdi, %rax
punpcklbw %xmm0, %xmm0
punpcklwd %xmm0, %xmm0
pshufd $0, %xmm0, %xmm0
L(entry_from_bzero):
cmpq $64, %rdx
ja L(loop_start)
cmpq $16, %rdx
jbe L(less_16_bytes)
cmpq $32, %rdx
movdqu %xmm0, (%rdi)
movdqu %xmm0, -16(%rdi,%rdx)
ja L(between_32_64_bytes)
L(return):
rep
ret
.p2align 4
L(between_32_64_bytes):
movdqu %xmm0, 16(%rdi)
movdqu %xmm0, -32(%rdi,%rdx)
ret
.p2align 4
L(loop_start):
leaq 64(%rdi), %rcx
movdqu %xmm0, (%rdi)
andq $-64, %rcx
movdqu %xmm0, -16(%rdi,%rdx)
movdqu %xmm0, 16(%rdi)
movdqu %xmm0, -32(%rdi,%rdx)
movdqu %xmm0, 32(%rdi)
movdqu %xmm0, -48(%rdi,%rdx)
movdqu %xmm0, 48(%rdi)
movdqu %xmm0, -64(%rdi,%rdx)
addq %rdi, %rdx
andq $-64, %rdx
cmpq %rdx, %rcx
je L(return)
.p2align 4
L(loop):
movdqa %xmm0, (%rcx)
movdqa %xmm0, 16(%rcx)
movdqa %xmm0, 32(%rcx)
movdqa %xmm0, 48(%rcx)
addq $64, %rcx
cmpq %rcx, %rdx
jne L(loop)
rep
ret
L(less_16_bytes):
movq %xmm0, %rcx
testb $24, %dl
jne L(between8_16bytes)
testb $4, %dl
jne L(between4_7bytes)
testb $1, %dl
je L(odd_byte)
movb %cl, (%rdi)
L(odd_byte):
testb $2, %dl
je L(return)
movw %cx, -2(%rax,%rdx)
ret
L(between4_7bytes):
movl %ecx, (%rdi)
movl %ecx, -4(%rdi,%rdx)
ret
L(between8_16bytes):
movq %rcx, (%rdi)
movq %rcx, -8(%rdi,%rdx)
ret
END (memset)
libc_hidden_builtin_def (memset)
#if defined PIC && IS_IN (libc) && !defined USE_MULTIARCH
strong_alias (__memset_chk, __memset_zero_constant_len_parameter)
.section .gnu.warning.__memset_zero_constant_len_parameter
.string "memset used with constant zero length parameter; this could be due to transposed parameters"
#endif
|
