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
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
|
/* Vector optimized 32/64 bit S/390 version of strcspn.
Copyright (C) 2015-2020 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-strcspn.h>
#if HAVE_STRCSPN_Z13
# include "sysdep.h"
# include "asm-syntax.h"
.text
/* size_t strcspn (const char *s, const char * reject)
The strcspn() function calculates the length of the initial segment
of s which consists entirely of characters not in reject.
This method checks the length of reject string. If it fits entirely
in one vector register, a fast algorithm is used, which does not need
to check multiple parts of accept-string. Otherwise a slower full
check of accept-string is used.
register overview:
r3: pointer to start of reject-string
r2: pointer to start of search-string
r0: loaded byte count of vlbb search-string
r4: found byte index
r1: current return len
v16: search-string
v17: reject-string
v18: temp-vreg
ONLY FOR SLOW:
v19: first reject-string
v20: zero for preparing acc-vector
v21: global mask; 1 indicates a match between
search-string-vreg and any reject-character
v22: current mask; 1 indicates a match between
search-string-vreg and any reject-character in current acc-vreg
v24: one for result-checking of former string-part
v30, v31: for re-/storing registers r6, r8, r9
r5: current len of reject-string
r6: zero-index in search-string or 16 if no zero
or min(zero-index, loaded byte count)
r8: >0, if former reject-string-part contains a zero,
otherwise =0;
r9: loaded byte count of vlbb reject-string
*/
ENTRY(STRCSPN_Z13)
.machine "z13"
.machinemode "zarch_nohighgprs"
/*
Check if reject-string fits in one vreg:
----------------------------------------
*/
vlbb %v17,0(%r3),6 /* Load reject. */
lghi %r1,0 /* Zero out current len. */
lcbb %r0,0(%r3),6
jo .Lcheck_onbb /* Special case if reject
lays on block-boundary. */
.Lcheck_notonbb:
vistrbs %v17,%v17 /* Fill with zeros after first zero. */
je .Lfast /* Zero found -> reject fits in one vreg. */
j .Lslow /* No zero -> reject exceeds one vreg. */
.Lcheck_onbb:
/* Reject lays on block-boundary. */
vfenezb %v18,%v17,%v17 /* Search zero in loaded reject bytes. */
vlgvb %r4,%v18,7 /* Get index of zero or 16 if not found. */
clrjl %r4,%r0,.Lcheck_notonbb /* Zero index < loaded bytes count ->
Reject fits in one vreg;
Fill with zeros and proceed
with FAST. */
vl %v17,0(%r3) /* Load reject, which exceeds loaded bytes. */
j .Lcheck_notonbb /* Check if reject fits in one vreg. */
/*
Search s for reject in one vreg
-------------------------------
*/
.Lfast:
/* Complete reject-string in v17 and remaining bytes are zero. */
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. */
vfaezbs %v18,%v16,%v17,0 /* Find first element in v16
unequal to any in v17
or first zero element. */
vlgvb %r4,%v18,7 /* Load byte index of found element. */
clrjl %r4,%r0,.Lfast_loop_found2 /* If found index is within loaded
bytes, return with found element
index (=equal count). */
/* Align s to 16 byte. */
risbgn %r4,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
lghi %r1,16 /* current_len = 16. */
slr %r1,%r4 /* Compute bytes to 16bytes boundary. */
/* Process s in 16byte aligned loop. */
.Lfast_loop:
vl %v16,0(%r1,%r2) /* Load search-string. */
vfaezbs %v18,%v16,%v17,0 /* Find first element in v16 equal to any
in v17 or first zero element. */
jno .Lfast_loop_found
vl %v16,16(%r1,%r2)
vfaezbs %v18,%v16,%v17,0
jno .Lfast_loop_found16
vl %v16,32(%r1,%r2)
vfaezbs %v18,%v16,%v17,0
jno .Lfast_loop_found32
vl %v16,48(%r1,%r2)
vfaezbs %v18,%v16,%v17,0
jno .Lfast_loop_found48
aghi %r1,64
j .Lfast_loop /* Loop if no element was unequal to reject
and not zero. */
/* Found equal or zero element. */
.Lfast_loop_found48:
aghi %r1,16
.Lfast_loop_found32:
aghi %r1,16
.Lfast_loop_found16:
aghi %r1,16
.Lfast_loop_found:
vlgvb %r4,%v18,7 /* Load byte index of found element or zero. */
.Lfast_loop_found2:
algrk %r2,%r1,%r4 /* Add found index to current len. */
br %r14
/*
Search s for reject in multiple vregs
-------------------------------------
*/
.Lslow:
/* Save registers. */
vlvgg %v30,%r6,0
vlvgp %v31,%r8,%r9
/* Reject in v17 without zero. */
vlr %v19,%v17 /* Save first acc-part for a fast reload. */
vzero %v20 /* Zero for preparing acc-vector. */
vone %v24 /* One for checking result of former
string-part. */
/* Align s to 16 byte. */
risbg %r4,%r2,60,128+63,0 /* Test if s is aligned and
%r4 = bits 60-63 'and' 15. */
je .Lslow_loop_str /* If s is aligned, loop aligned. */
lghi %r0,15
slr %r0,%r4 /* Compute highest index to load (15-x). */
vll %v16,%r0,0(%r2) /* Load up to 16 byte boundary (vll needs
highest index, remaining bytes are 0). */
ahi %r0,1 /* Work with loaded byte count. */
vzero %v21 /* Zero out global mask. */
lghi %r5,0 /* Set current len of reject-string to zero. */
vfenezb %v18,%v16,%v16 /* Find zero in current string-part. */
lghi %r8,0 /* There is no zero in first reject-part. */
vlgvb %r6,%v18,7 /* Load byte index of zero or 16 if no zero. */
clije %r6,0,.Lslow_end /* If first element is zero -> return 0. */
clr %r0,%r6 /* cc==1 if loaded byte count < zero-index. */
locrl %r6,%r0 /* Load on cc==1; zero-index = lbc. */
j .Lslow_loop_acc
/* Process s in 16byte aligned loop. */
.Lslow_next_str:
/* Check results of former processed str-part. */
vfeeb %v18,%v21,%v24 /* Find first equal match in global mask
(ones in element). */
vlgvb %r4,%v18,7 /* Get index of first one (=equal) or 16. */
/* Equal-index < min(zero-index, loaded byte count)
-> Return pointer to equal element. */
clrjl %r4,%r6,.Lslow_index_found
/* Zero-index < loaded byte count
-> Former str-part was last str-part
-> Return null */
clrjl %r6,%r0,.Lslow_end_not_found
/* All elements are zero (=no match) -> Proceed with next str-part. */
vlr %v17,%v19 /* Load first part of reject (no zero). */
algfr %r1,%r0 /* Add loaded byte count to current len. */
.Lslow_loop_str:
vl %v16,0(%r1,%r2) /* Load search-string. */
lghi %r0,16 /* Loaded byte count is 16. */
vzero %v21 /* Zero out global mask. */
lghi %r5,0 /* Set current len of reject to zero. */
vfenezb %v18,%v16,%v16 /* Find zero in current string-part. */
lghi %r8,0 /* There is no zero in first reject-part. */
vlgvb %r6,%v18,7 /* Load byte index of zero or 16 if no zero. */
clije %r6,0,.Lslow_end /* If first element is zero (end of string)
-> Return current length. */
.Lslow_loop_acc:
vfaeb %v22,%v16,%v17,4 /* Create matching-mask (1 in mask ->
Character matches any rejected character in
this reject-string-part) IN=0, RT=1. */
vlgvb %r4,%v22,0 /* Get result of first element. */
/* First element is equal to any rejected characters?
(all other parts of reject cannot lead to a match before this one)
-> Return current len, which is pointing to this element. */
clijh %r4,0,.Lslow_end
vo %v21,%v21,%v22 /* Global-mask = global-|matching-mask. */
/* Proceed with next acc until end of acc is reached. */
.Lslow_next_acc:
clijh %r8,0,.Lslow_next_str /* There was a zero in last reject-part
-> Add found index to current len
and end. */
vlbb %v17,16(%r5,%r3),6 /* Load next reject part. */
aghi %r5,16 /* Increment current len of reject-string. */
lcbb %r9,0(%r5,%r3),6 /* Get loaded byte count of reject-string. */
jo .Lslow_next_acc_onbb /* Jump away if reject-string is
on block-boundary. */
.Lslow_next_acc_notonbb:
vistrbs %v17,%v17 /* Fill with zeros after first zero. */
jo .Lslow_loop_acc /* No zero found -> no preparation needed. */
.Lslow_next_acc_prepare_zero:
/* Zero in reject-part: fill zeros with first-reject-character. */
vlgvb %r8,%v17,0 /* Load first element of reject-part. */
clije %r8,0,.Lslow_next_str /* Process next str-part if first
character in this part of reject
is a zero. */
/* r8>0 -> zero found in this acc-part. */
vrepb %v18,%v17,0 /* Replicate first char accross all chars. */
vceqb %v22,%v20,%v17 /* Create a mask (v22) of null chars
by comparing with 0 (v20). */
vsel %v17,%v18,%v17,%v22 /* Replace null chars with first char. */
j .Lslow_loop_acc /* Reject-string part is prepared. */
.Lslow_next_acc_onbb:
vfenezb %v18,%v17,%v17 /* Find zero in loaded bytes of reject part. */
vlgvb %r8,%v18,7 /* Load byte index of zero. */
clrjl %r8,%r9,.Lslow_next_acc_notonbb /* Found a zero in loaded bytes
-> Prepare vreg. */
vl %v17,0(%r5,%r3) /* Load over boundary ... */
lghi %r8,0 /* r8=0 -> no zero in this part of acc,
check for zero is in jump-target. */
j .Lslow_next_acc_notonbb /* ... and search for zero in
fully loaded vreg again. */
.Lslow_end_not_found:
algfr %r1,%r6 /* Add zero-index to current len. */
j .Lslow_end
.Lslow_index_found:
algfr %r1,%r4 /* Add found index of char to current len. */
.Lslow_end:
lgr %r2,%r1
/* Restore registers. */
vlgvg %r6,%v30,0
vlgvg %r8,%v31,0
vlgvg %r9,%v31,1
br %r14
END(STRCSPN_Z13)
# if ! HAVE_STRCSPN_IFUNC
strong_alias (STRCSPN_Z13, strcspn)
# endif
# if ! HAVE_STRCSPN_C && defined SHARED && IS_IN (libc)
strong_alias (STRCSPN_Z13, __GI_strcspn)
# endif
#endif /* HAVE_STRCSPN_Z13 */
|
