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
|
/* Vector optimized 32/64 bit S/390 version of strncmp.
Copyright (C) 2015-2023 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-strncmp.h>
#if HAVE_STRNCMP_Z13
# include "sysdep.h"
# include "asm-syntax.h"
.text
/* int strncmp (const char *s1, const char *s2, size_t n)
Compare at most n characters of two strings.
Register usage:
-r0=tmp
-r1=tmp
-r2=s1
-r3=s2
-r4=n
-r5=current_len
-v16=part of s1
-v17=part of s2
-v18=index of unequal
*/
ENTRY(STRNCMP_Z13)
.machine "z13"
.machinemode "zarch_nohighgprs"
# if !defined __s390x__
llgfr %r4,%r4
# endif /* !defined __s390x__ */
clgije %r4,0,.Lend_equal /* Nothing to do if n == 0, */
lghi %r5,0 /* current_len = 0. */
.Lloop:
vlbb %v16,0(%r5,%r2),6 /* Load s1 to block boundary. */
vlbb %v17,0(%r5,%r3),6 /* Load s2 to block boundary. */
lcbb %r0,0(%r5,%r2),6 /* Get loaded byte count of s1. */
jo .Llt16_1 /* Jump away if vr is not fully loaded. */
lcbb %r1,0(%r5,%r3),6 /* Get loaded byte count of s2. */
jo .Llt16_2 /* Jump away if vr is not fully loaded. */
aghi %r5,16 /* Both vrs are fully loaded. */
clgrjhe %r5,%r4,.Llastcmp /* If current_len >= n ->last compare. */
vfenezbs %v18,%v16,%v17 /* Compare not equal with zero search. */
jno .Lfound
vlbb %v16,0(%r5,%r2),6
vlbb %v17,0(%r5,%r3),6
lcbb %r0,0(%r5,%r2),6
jo .Llt16_1
lcbb %r1,0(%r5,%r3),6
jo .Llt16_2
aghi %r5,16
clgrjhe %r5,%r4,.Llastcmp
vfenezbs %v18,%v16,%v17
jno .Lfound
vlbb %v16,0(%r5,%r2),6
vlbb %v17,0(%r5,%r3),6
lcbb %r0,0(%r5,%r2),6
jo .Llt16_1
lcbb %r1,0(%r5,%r3),6
jo .Llt16_2
aghi %r5,16
clgrjhe %r5,%r4,.Llastcmp
vfenezbs %v18,%v16,%v17
jno .Lfound
vlbb %v16,0(%r5,%r2),6
vlbb %v17,0(%r5,%r3),6
lcbb %r0,0(%r5,%r2),6
jo .Llt16_1
lcbb %r1,0(%r5,%r3),6
jo .Llt16_2
aghi %r5,16
clgrjhe %r5,%r4,.Llastcmp
vfenezbs %v18,%v16,%v17
jno .Lfound
j .Lloop
.Llt16_1:
lcbb %r1,0(%r5,%r3),6 /* Get loaded byte count ofs2. */
.Llt16_2:
clr %r0,%r1 /* Compare logical. */
locrh %r0,%r1 /* Compute minimum of bytes loaded. */
algfr %r5,%r0 /* Add smallest loaded bytes to current_len. */
clgrj %r5,%r4,10,.Llastcmp /* If current_len >= n ->last compare. */
vfenezbs %v18,%v16,%v17 /* Compare not equal with zero search. */
vlgvb %r1,%v18,7 /* Get not equal index or 16 if all equal. */
clrjl %r1,%r0,.Lfound /* Jump away if miscompare is within
loaded bytes (index < loaded-bytes) */
j .Lloop
.Llastcmp:
/* Use comparison result only if located within first n characters.
%r0: loaded byte count in vreg;
%r5: current_len;
%r4: n;
(current_len - n): [0...16[
First ignored match index: loaded bytes - (current_len-n): ]0...16]
*/
slgr %r5,%r4 /* %r5 = current_len - n. */
slr %r0,%r5 /* %r0 = first ignored match index. */
vfenezbs %v18,%v16,%v17 /* Compare not equal with zero search. */
vlgvb %r1,%v18,7 /* Get not equal index or 16 if all equal. */
clrjl %r1,%r0,.Lfound /* Jump away if miscompare is within
loaded bytes and below n bytes. */
j .Lend_equal /* Miscompare after n-bytes -> end equal. */
.Lfound:
/* Difference or end of string. */
je .Lend_equal
lghi %r2,1
lghi %r1,-1
locgrl %r2,%r1
br %r14
.Lend_equal:
lghi %r2,0
br %r14
END(STRNCMP_Z13)
# if ! HAVE_STRNCMP_IFUNC
strong_alias (STRNCMP_Z13, strncmp)
# endif
# if ! HAVE_STRNCMP_C && defined SHARED && IS_IN (libc)
strong_alias (STRNCMP_Z13, __GI_strncmp)
# endif
#endif /* HAVE_STRNCMP_Z13 */
|
