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
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
/* Vector optimized 32/64 bit S/390 version of wcsnlen.
Copyright (C) 2015-2022 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/>. */
#include <ifunc-wcsnlen.h>
#if HAVE_WCSNLEN_Z13
# include "sysdep.h"
# include "asm-syntax.h"
.text
/* size_t wcsnlen (const wchar_t *s, size_t maxlen)
Returns the number of characters in s or at most maxlen.
Register usage:
-r1=tmp
-r2=address of string
-r3=maxlen (number of characters to be read)
-r4=tmp
-r5=current_len and return_value
-v16=part of s
*/
ENTRY(WCSNLEN_Z13)
.machine "z13"
.machinemode "zarch_nohighgprs"
# if !defined __s390x__
llgfr %r3,%r3
# endif /* !defined __s390x__ */
clgfi %r3,0 /* if maxlen == 0, return 0. */
locgre %r2,%r3
ber %r14
vlbb %v16,0(%r2),6 /* Load s until next 4k-byte boundary. */
lcbb %r1,0(%r2),6 /* Get bytes to 4k-byte boundary or 16. */
llgfr %r1,%r1 /* Convert 32bit to 64bit. */
tmll %r2,3 /* Test if s is 4-byte aligned? */
jne .Lfallback /* And use common-code variant if not. */
/* Check range of maxlen and convert to byte-count. */
# ifdef __s390x__
tmhh %r3,49152 /* Test bit 0 or 1 of maxlen. */
lghi %r4,-4 /* Max byte-count is 18446744073709551612. */
# else
tmlh %r3,49152 /* Test bit 0 or 1 of maxlen. */
llilf %r4,4294967292 /* Max byte-count is 4294967292. */
# endif /* !__s390x__ */
sllg %r3,%r3,2 /* Convert character-count to byte-count. */
locgrne %r3,%r4 /* Use max byte-count, if bit 0/1 was one. */
vfenezf %v16,%v16,%v16 /* Find element not equal with zero search. */
clgr %r1,%r3
locgrh %r1,%r3 /* loaded_byte_count
= min (loaded_byte_count, maxlen) */
vlgvb %r5,%v16,7 /* Load zero index or 16 if not found. */
clrjl %r5,%r1,.Lend /* Found zero within loaded bytes -> return. */
clgr %r1,%r3 /* If loaded_byte_count == maxlen -> end. */
locgre %r5,%r3
je .Lend
/* Align s to 16 byte. */
risbgn %r4,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
lghi %r5,16 /* current_len = 16. */
slr %r5,%r4 /* Compute bytes to 16bytes boundary. */
lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */
aghi %r1,64
clgrjl %r1,%r3,.Lloop64
/* Find zero in max 64byte with aligned s. */
.Llt64:
vl %v16,0(%r5,%r2) /* Load s. */
vfenezfs %v16,%v16,%v16 /* Find element not equal with zero search. */
je .Lfound /* Jump away if zero was found. */
aghi %r5,16
clgrjhe %r5,%r3,.Lfound /* If current_len >= maxlen -> end. */
vl %v16,0(%r5,%r2)
vfenezfs %v16,%v16,%v16
je .Lfound
aghi %r5,16
clgrjhe %r5,%r3,.Lfound
vl %v16,0(%r5,%r2)
vfenezfs %v16,%v16,%v16
je .Lfound
aghi %r5,16
clgrjhe %r5,%r3,.Lfound
vl %v16,0(%r5,%r2)
vfenezfs %v16,%v16,%v16
j .Lfound
.Lfound48:
aghi %r5,16
.Lfound32:
aghi %r5,16
.Lfound16:
aghi %r5,16
.Lfound:
vlgvb %r4,%v16,7 /* Load byte index of zero or 16 if no zero. */
algr %r5,%r4
clgr %r5,%r3
locgrh %r5,%r3 /* Return min (current_len, maxlen). */
.Lend:
srlg %r2,%r5,2 /* Convert byte-count to character-count. */
br %r14
/* Find zero in 16byte aligned loop. */
.Lloop64:
vl %v16,0(%r5,%r2) /* Load s. */
vfenezfs %v16,%v16,%v16 /* Find element not equal with zero search. */
je .Lfound /* Jump away if zero was found. */
vl %v16,16(%r5,%r2)
vfenezfs %v16,%v16,%v16
je .Lfound16
vl %v16,32(%r5,%r2)
vfenezfs %v16,%v16,%v16
je .Lfound32
vl %v16,48(%r5,%r2)
vfenezfs %v16,%v16,%v16
je .Lfound48
aghi %r5,64
lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */
aghi %r1,64
clgrjl %r1,%r3,.Lloop64
j .Llt64
.Lfallback:
jg WCSNLEN_C
END(WCSNLEN_Z13)
# if ! HAVE_WCSNLEN_IFUNC
strong_alias (WCSNLEN_Z13, __wcsnlen)
weak_alias (__wcsnlen, wcsnlen)
# endif
#endif
|
