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
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
|
/* Vector optimized 32/64 bit S/390 version of strncat.
Copyright (C) 2015-2018 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 <ifunc-strncat.h>
#if HAVE_STRNCAT_Z13
# include "sysdep.h"
# include "asm-syntax.h"
.text
/* char * strncat (const char *dest, const char *src, size_t n)
Concatenate two strings - at most n characters of src.
Register usage:
-r0=saved dest pointer for return
-r1=tmp
-r2=dest
-r3=src
-r4=n
-r5=current_len
-r6=tmp
-r7=tmp
-v16=part of src
-v17=index of zero
-v18=part of src
-v31=register save area for r6, r7
*/
ENTRY(STRNCAT_Z13)
.machine "z13"
.machinemode "zarch_nohighgprs"
# if !defined __s390x__
llgfr %r4,%r4
# endif /* !defined __s390x__ */
clgfi %r4,0
ber %r14 /* Nothing to do, if n == 0. */
lgr %r0,%r2 /* Save destination pointer for return. */
vlvgp %v31,%r6,%r7 /* Save registers. */
/* STRLEN
%r1 = loaded bytes (tmp)
%r6 = zero byte index (tmp)
%r2 = dst
*/
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. */
vfenezb %v16,%v16,%v16 /* Find element not equal with zero search. */
vlgvb %r5,%v16,7 /* Load zero index or 16 if not found. */
clrjl %r5,%r1,.Llen_end /* Found zero within loaded bytes, end. */
/* Align s to 16 byte. */
risbgn %r1,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
lghi %r5,16 /* current_len = 16. */
slr %r5,%r1 /* Compute bytes to 16bytes boundary. */
/* Find zero in 16byte aligned loop. */
.Llen_loop:
vl %v16,0(%r5,%r2) /* Load s. */
vfenezbs %v16,%v16,%v16 /* Find element not equal with zero search. */
je .Llen_found /* Jump away if zero was found. */
vl %v16,16(%r5,%r2)
vfenezbs %v16,%v16,%v16
je .Llen_found16
vl %v16,32(%r5,%r2)
vfenezbs %v16,%v16,%v16
je .Llen_found32
vl %v16,48(%r5,%r2)
vfenezbs %v16,%v16,%v16
je .Llen_found48
aghi %r5,64
j .Llen_loop /* No zero -> loop. */
.Llen_found48:
aghi %r5,16
.Llen_found32:
aghi %r5,16
.Llen_found16:
aghi %r5,16
.Llen_found:
vlgvb %r1,%v16,7 /* Load byte index of zero. */
algr %r5,%r1
.Llen_end:
/* STRCPY
%r1 = zero byte index (tmp)
%r6 = loaded bytes (tmp)
%r3 = curr src pointer
%r2 = curr dst pointer
%r7 = border, tmp
*/
la %r2,0(%r5,%r2) /* strcpy at end of dst-string. */
vlbb %v16,0(%r3),6 /* Load s until next 4k-byte boundary. */
lcbb %r6,0(%r3),6 /* Get bytes to 4k-byte boundary or 16. */
llgfr %r6,%r6 /* Convert 32bit to 64bit. */
lghi %r5,0 /* current_len = 0. */
clgrjle %r4,%r6,.Lcpy_remaining_v16 /* If n <= loaded-bytes
-> process remaining. */
/* n > loaded-byte-count. */
vfenezb %v17,%v16,%v16 /* Find element not equal with zero search. */
vlgvb %r1,%v17,7 /* Load zero index or 16 if not found. */
clrjl %r1,%r6,.Lcpy_found_v16_store /* Found zero within loaded
bytes, copy and return. */
/* Align s to 16 byte. */
risbgn %r7,%r3,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
lghi %r5,15 /* current_len = 15. */
slr %r5,%r7 /* Compute highest index to 16byte boundary. */
/* Zero not found and n > loaded-byte-count. */
vstl %v16,%r5,0(%r2) /* Copy loaded characters - no zero. */
ahi %r5,1 /* Start loop at next character. */
/*
Now we are 16byte aligned, so we can load a full vreg
without page fault.
*/
lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */
aghi %r1,64
clgrjl %r1,%r4,.Lcpy_loop64
vl %v16,0(%r5,%r3) /* Load s. */
clgijl %r4,17,.Lcpy_remaining_v16 /* If n <=16,
process remaining bytes. */
.Lcpy_lt64:
lgr %r7,%r4
slgfi %r7,16 /* border_len = n - 16. */
/* If current_len >= border then process remaining bytes. */
clgrjhe %r5,%r7,.Lcpy_remaining_v16
vfenezbs %v17,%v16,%v16 /* Find element not equal with zero search. */
je .Lcpy_found_v16 /* Jump away if zero was found. */
vl %v18,16(%r5,%r3) /* Load next part of s. */
vst %v16,0(%r5,%r2) /* Store previous part without zero to dst. */
aghi %r5,16
clgrjhe %r5,%r7,.Lcpy_remaining_v18
vfenezbs %v17,%v18,%v18
je .Lcpy_found_v18
vl %v16,16(%r5,%r3)
vst %v18,0(%r5,%r2)
aghi %r5,16
clgrjhe %r5,%r7,.Lcpy_remaining_v16
vfenezbs %v17,%v16,%v16
je .Lcpy_found_v16
vl %v18,16(%r5,%r3)
vst %v16,0(%r5,%r2)
aghi %r5,16
.Lcpy_remaining_v18:
vlr %v16,%v18
.Lcpy_remaining_v16:
/* v16 contains the remaining bytes [1...16].
Store remaining bytes and append string-termination. */
vfenezb %v17,%v16,%v16 /* Find element not equal with zero search. */
slgrk %r7,%r4,%r5 /* Remaining bytes = maxlen - current_len. */
aghi %r7,-1 /* vstl needs highest index. */
vlgvb %r1,%v17,7 /* Load zero index or 16 if not found. */
la %r2,0(%r5,%r2) /* vstl has no index register. */
/* Zero-index within remaining-bytes, store up to zero and end. */
clgrjle %r1,%r7,.Lcpy_found_v16_store
vstl %v16,%r7,0(%r2) /* Store remaining bytes. */
lghi %r1,0
stc %r1,1(%r7,%r2) /* Store string-null-termination beyond n. */
.Lcpy_end:
/* Restore saved registers. */
vlgvg %r6,%v31,0
vlgvg %r7,%v31,1
lgr %r2,%r0 /* Load saved dest-ptr. */
br %r14
.Lcpy_found_v16_32:
aghi %r5,32
j .Lcpy_found_v16
.Lcpy_found_v18_48:
aghi %r5,32
.Lcpy_found_v18_16:
aghi %r5,16
.Lcpy_found_v18:
vlr %v16,%v18
.Lcpy_found_v16:
/* v16 contains a zero. Store remaining bytes to zero. current_len
has not reached border, thus checking for n is not needed! */
vlgvb %r1,%v17,7 /* Load byte index of zero. */
la %r2,0(%r5,%r2)
.Lcpy_found_v16_store:
vstl %v16,%r1,0(%r2) /* Copy characters including zero. */
j .Lcpy_end
/* Find zero in 16byte aligned loop. */
.Lcpy_loop64:
vl %v16,0(%r5,%r3) /* Load s. */
vfenezbs %v17,%v16,%v16 /* Find element not equal with zero search. */
je .Lcpy_found_v16 /* Jump away if zero was found. */
vl %v18,16(%r5,%r3) /* Load next part of s. */
vst %v16,0(%r5,%r2) /* Store previous part without zero to dst. */
vfenezbs %v17,%v18,%v18
je .Lcpy_found_v18_16
vl %v16,32(%r5,%r3)
vst %v18,16(%r5,%r2)
vfenezbs %v17,%v16,%v16
je .Lcpy_found_v16_32
vl %v18,48(%r5,%r3)
vst %v16,32(%r5,%r2)
vfenezbs %v17,%v18,%v18
je .Lcpy_found_v18_48
vst %v18,48(%r5,%r2)
aghi %r5,64
lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */
aghi %r1,64
clgrjl %r1,%r4,.Lcpy_loop64
vl %v16,0(%r5,%r3) /* Load s. */
j .Lcpy_lt64
END(STRNCAT_Z13)
# if ! HAVE_STRNCAT_IFUNC
strong_alias (STRNCAT_Z13, strncat)
# endif
# if ! HAVE_STRNCAT_C
/* See string/strncat.c and define STRNCAT_PRIMARY. */
strong_alias (STRNCAT_Z13, __strncat)
# if defined SHARED && IS_IN (libc)
strong_alias (__strncat, __GI___strncat)
# endif
# endif
#endif
|