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
|
/* strlen with SSE4
Copyright (C) 2009-2013 Free Software Foundation, Inc.
Contributed by Ulrich Drepper <drepper@redhat.com>.
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/>. */
#if defined SHARED && !defined NOT_IN_libc
#include <sysdep.h>
.section .text.sse4.2,"ax",@progbits
ENTRY (__strlen_sse42)
pxor %xmm1, %xmm1
movl %edi, %ecx
movq %rdi, %r8
andq $~15, %rdi
xor %edi, %ecx
pcmpeqb (%rdi), %xmm1
pmovmskb %xmm1, %edx
shrl %cl, %edx
shll %cl, %edx
andl %edx, %edx
jnz L(less16bytes)
pxor %xmm1, %xmm1
.p2align 4
L(more64bytes_loop):
pcmpistri $0x08, 16(%rdi), %xmm1
jz L(more32bytes)
pcmpistri $0x08, 32(%rdi), %xmm1
jz L(more48bytes)
pcmpistri $0x08, 48(%rdi), %xmm1
jz L(more64bytes)
add $64, %rdi
pcmpistri $0x08, (%rdi), %xmm1
jnz L(more64bytes_loop)
leaq (%rdi,%rcx), %rax
subq %r8, %rax
ret
.p2align 4
L(more32bytes):
leaq 16(%rdi,%rcx, 1), %rax
subq %r8, %rax
ret
.p2align 4
L(more48bytes):
leaq 32(%rdi,%rcx, 1), %rax
subq %r8, %rax
ret
.p2align 4
L(more64bytes):
leaq 48(%rdi,%rcx, 1), %rax
subq %r8, %rax
ret
.p2align 4
L(less16bytes):
subq %r8, %rdi
bsfl %edx, %eax
addq %rdi, %rax
ret
END (__strlen_sse42)
#endif
|
