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
158
159
160
161
162
163
|
/* Vector optimized 32/64 bit S/390 version of memchr.
Copyright (C) 2015-2019 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-memchr.h>
#if HAVE_MEMCHR_Z13
# include "sysdep.h"
# include "asm-syntax.h"
.text
/* void *memchr (const void *s, int c, size_t n)
Scans memory for character c
and returns pointer to first c.
Register usage:
-r0=tmp
-r1=tmp
-r2=s
-r3=c
-r4=n
-r5=current_len
-v16=part of s
-v17=index of found c
-v18=c replicated
*/
ENTRY(MEMCHR_Z13)
.machine "z13"
.machinemode "zarch_nohighgprs"
# if !defined __s390x__
llgfr %r4,%r4
# endif /* !defined __s390x__ */
clgije %r4,0,.Lnf_end /* If len == 0 then exit. */
vlbb %v16,0(%r2),6 /* Load s until next 4k-byte boundary. */
lcbb %r0,0(%r2),6 /* Get bytes to 4k-byte boundary or 16. */
llgfr %r0,%r0 /* Convert 32bit to 64bit. */
vlvgb %v18,%r3,0 /* Generate vector which elements are all c.
if c > 255, c will be truncated. */
vrepb %v18,%v18,0
lghi %r5,16 /* current_len = 16. */
clgrjhe %r0,%r4,.Llastcmp /* If (bytes to boundary) >= n,
jump to lastcmp. */
vfeebs %v17,%v16,%v18 /* Find c. */
vlgvb %r1,%v17,7 /* Load byte index of c. */
clgrjl %r1,%r0,.Lfound2 /* Found c is within loaded bytes. */
/* Align s to 16 byte. */
risbgn %r1,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
slr %r5,%r1 /* Compute bytes to 16bytes boundary. */
lgr %r0,%r5 /* If %r5 + 64 < n? -> loop64. */
aghi %r0,64
clgrjl %r0,%r4,.Lloop64
.Llt64:
vl %v16,0(%r5,%r2)
aghi %r5,16
clgrjhe %r5,%r4,.Llastcmp /* Do last compare if curr-len >= n. */
vfeebs %v17,%v16,%v18 /* Find c. */
jl .Lfound /* Jump away if c was found. */
vl %v16,0(%r5,%r2)
aghi %r5,16
clgrjhe %r5,%r4,.Llastcmp
vfeebs %v17,%v16,%v18
jl .Lfound
vl %v16,0(%r5,%r2)
aghi %r5,16
clgrjhe %r5,%r4,.Llastcmp
vfeebs %v17,%v16,%v18
jl .Lfound
vl %v16,0(%r5,%r2)
aghi %r5,16
.Llastcmp:
/* Use comparision result only if located within first n characters.
%r5: current_len;
%r4: n;
(current_len - n): [0...16[
first ignored match index: vr-width - (current_len - n) ]0...16]
*/
vfeebs %v17,%v16,%v18 /* Find c. */
slgrk %r4,%r5,%r4 /* %r5 = current_len - n. */
lghi %r0,16 /* Register width = 16. */
vlgvb %r1,%v17,7 /* Extract found index or 16 if all equal. */
slr %r0,%r4 /* %r0 = first ignored match index. */
clrjl %r1,%r0,.Lfound2 /* Go away if miscompare is below n bytes. */
/* c not found within n-bytes. */
.Lnf_end:
lghi %r2,0 /* Return null. */
br %r14
.Lfound48:
aghi %r5,16
.Lfound32:
aghi %r5,16
.Lfound16:
aghi %r5,16
.Lfound0:
aghi %r5,16
.Lfound:
vlgvb %r1,%v17,7 /* Load byte index of c. */
.Lfound2:
slgfi %r5,16 /* current_len -=16 */
algr %r5,%r1 /* Zero byte index is added to current len. */
la %r2,0(%r5,%r2) /* Return pointer to c. */
br %r14
.Lloop64:
vl %v16,0(%r5,%r2)
vfeebs %v17,%v16,%v18 /* Find c. */
jl .Lfound0 /* Jump away if c was found. */
vl %v16,16(%r5,%r2)
vfeebs %v17,%v16,%v18
jl .Lfound16
vl %v16,32(%r5,%r2)
vfeebs %v17,%v16,%v18
jl .Lfound32
vl %v16,48(%r5,%r2)
vfeebs %v17,%v16,%v18
jl .Lfound48
aghi %r5,64
lgr %r0,%r5 /* If %r5 + 64 < n? -> loop64. */
aghi %r0,64
clgrjl %r0,%r4,.Lloop64
j .Llt64
END(MEMCHR_Z13)
# if ! HAVE_MEMCHR_IFUNC
strong_alias (MEMCHR_Z13, __memchr)
weak_alias (__memchr, memchr)
# endif
# if ! HAVE_MEMCHR_Z900_G5 && defined SHARED && IS_IN (libc)
strong_alias (MEMCHR_Z13, __GI_memchr)
# endif
#endif
|
GitWeb