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
|
/* Vector optimized 32/64 bit S/390 version of strspn.
Copyright (C) 2015-2021 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-strspn.h>
#if HAVE_STRSPN_Z13
# include "sysdep.h"
# include "asm-syntax.h"
.text
/* size_t strspn (const char *s, const char * accept)
The strspn() function calculates the length of the initial segment
of s which consists entirely of characters in accept.
This method checks the length of accept 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 accept-string
r2: pointer to start of search-string
r4: loaded byte count of vl search-string
r0: found byte index
r1: current return len of s
v16: search-string
v17: accept-string
v18: temp-vreg
ONLY FOR SLOW:
v19: first accept-string
v20: zero for preparing acc-vector
v21: global mask; 1 indicates a match between
search-string-vreg and any accept-character
v22: current mask; 1 indicates a match between
search-string-vreg and any accept-character in current acc-vreg
v30, v31: for re-/storing registers r6, r8, r9
r5: current len of accept-string
r6: zero-index in search-string or 16 if no zero
or min(zero-index, loaded byte count)
r8: >0, if former accept-string-part contains a zero,
otherwise =0;
r9: loaded byte count of vlbb accept-string
*/
ENTRY(STRSPN_Z13)
.machine "z13"
.machinemode "zarch_nohighgprs"
/*
Check if accept-string fits in one vreg:
----------------------------------------
*/
vlbb %v17,0(%r3),6 /* Load accept. */
lcbb %r4,0(%r3),6
jo .Lcheck_onbb /* Special case if accept lays
on block-boundary. */
.Lcheck_notonbb:
vistrbs %v17,%v17 /* Fill with zeros after first zero. */
je .Lfast /* Zero found -> accept fits in one vreg. */
j .Lslow /* No zero -> accept exceeds one vreg. */
.Lcheck_onbb:
/* Accept lays on block-boundary. */
vfenezb %v18,%v17,%v17 /* Search zero in loaded accept bytes. */
vlgvb %r0,%v18,7 /* Get index of zero or 16 if not found. */
clrjl %r0,%r4,.Lcheck_notonbb /* Zero index < loaded bytes count ->
Accept fits in one vreg;
Fill with zeros and proceed
with FAST. */
vl %v17,0(%r3) /* Load accept, which exceeds loaded bytes. */
j .Lcheck_notonbb /* Check if accept fits in one vreg. */
/*
Search s for accept in one vreg
-------------------------------
*/
.Lfast:
/* Complete accept-string is in v17 and remaining bytes are zero. */
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. */
vfaezbs %v16,%v16,%v17,8 /* Find first element in v16
unequal to any in v17
or first zero element. */
vlgvb %r0,%v16,7 /* Load byte index of found element. */
/* If found index is within loaded bytes (%r0 < %r1),
return with found element index (=equal count). */
clr %r0,%r1
locgrl %r2,%r0
blr %r14
/* 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. */
.Lfast_loop:
vl %v16,0(%r1,%r2) /* Load search-string. */
vfaezbs %v16,%v16,%v17,8 /* Find first element in v16
unequal to any in v17
or first zero element. */
jno .Lfast_loop_found
vl %v16,16(%r1,%r2)
vfaezbs %v16,%v16,%v17,8
jno .Lfast_loop_found16
vl %v16,32(%r1,%r2)
vfaezbs %v16,%v16,%v17,8
jno .Lfast_loop_found32
vl %v16,48(%r1,%r2)
vfaezbs %v16,%v16,%v17,8
jno .Lfast_loop_found48
aghi %r1,64
j .Lfast_loop /* Loop if no element was unequal to accept
and not zero. */
/* Found unequal 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 %r0,%v16,7 /* Load byte index of found element. */
algrk %r2,%r1,%r0 /* And add it to current len. */
br %r14
/*
Search s for accept in multiple vregs
-------------------------------------
*/
.Lslow:
/* Save registers. */
vlvgg %v30,%r6,0
vlvgp %v31,%r8,%r9
lghi %r1,0 /* current_len = 0. */
/* Accept in v17 without zero. */
vlr %v19,%v17 /* Save first acc-part for a fast reload. */
vzero %v20 /* Zero for preparing acc-vector. */
/* Align s to 16 byte. */
risbg %r0,%r2,60,128+63,0 /* Test if s is aligned and
%r0 = bits 60-63 'and' 15 */
je .Lslow_loop_str /* If s is aligned, loop aligned */
lghi %r4,15
slr %r4,%r0 /* Compute highest index to load (15-x). */
vll %v16,%r4,0(%r2) /* Load up to 16byte boundary (vll needs
highest index, left bytes are 0). */
ahi %r4,1 /* Work with loaded byte count. */
vzero %v21 /* Zero out global mask. */
lghi %r5,0 /* Set current len of accept-string to zero. */
vfenezb %v18,%v16,%v16 /* Find zero in current string-part. */
lghi %r8,0 /* There is no zero in first accept-part. */
vlgvb %r6,%v18,7 /* Load byte index of zero or 16
if there is no zero. */
clr %r4,%r6 /* cc==1 if loaded byte count < zero-index. */
locrl %r6,%r4 /* Load on cc==1. */
j .Lslow_loop_acc
/* Process s in 16byte aligned loop. */
.Lslow_next_str:
vlr %v17,%v19 /* Load first part of accept (no zero). */
algfr %r1,%r4 /* Add loaded byte count to current len. */
.Lslow_loop_str:
vl %v16,0(%r1,%r2) /* Load search-string. */
lghi %r4,16 /* Loaded byte count is 16. */
vzero %v21 /* Zero out global mask. */
lghi %r5,0 /* Set current len of accept-string to zero. */
vfenezb %v18,%v16,%v16 /* Find zero in current string-part. */
lghi %r8,0 /* There is no zero in first accept-part. */
vlgvb %r6,%v18,7 /* Load byte index of zero or 16 if no zero. */
.Lslow_loop_acc:
vfaeb %v22,%v16,%v17,4 /* Create matching-mask (1 in mask ->
character matches any accepted character in
this accept-string-part) IN=0, RT=1. */
vo %v21,%v21,%v22 /* global-mask = global- | matching-mask. */
vfenezb %v18,%v21,%v21 /* Find first zero in global-mask. */
vlgvb %r0,%v18,7 /* Get first found zero-index
(= first mismatch). */
clrjl %r0,%r6,.Lslow_next_acc /* Mismatch-index < min(lbc,zero-index)
-> Process this string-part
with next acc-part. */
clrjhe %r0,%r4,.Lslow_next_str /* Found-index >= loaded byte count
-> All loaded bytes are matching
any accept-character
and are not zero. */
/* All bytes are matching any characters in accept-string
and search-string is fully processed (found-index == zero-index) */
.Lslow_add_lbc_end:
algrk %r2,%r1,%r0 /* Add matching characters to current_len. */
/* Restore registers. */
vlgvg %r6,%v30,0
vlgvg %r8,%v31,0
vlgvg %r9,%v31,1
br %r14
.Lslow_next_acc:
clijh %r8,0,.Lslow_add_lbc_end /* There was a zero in last acc-part
-> Add found index to current len
and end. */
vlbb %v17,16(%r5,%r3),6 /* Load next accept part. */
aghi %r5,16 /* Add current_len of accept-string. */
lcbb %r9,0(%r5,%r3),6 /* Get loaded byte count of accept-string. */
jo .Lslow_next_acc_onbb /* Jump away if accept-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 accept-part: fill zeros with first-accept-character. */
vlgvb %r8,%v17,0 /* Load first element of acc-part. */
clije %r8,0,.Lslow_add_lbc_end /* End if zero is first character
in this part of accept-string. */
/* 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 /* Accept part is prepared -> process. */
.Lslow_next_acc_onbb:
vfenezb %v18,%v17,%v17 /* Find zero in loaded bytes of accept part. */
vlgvb %r8,%v18,7 /* Load byte index of zero. */
clrjl %r8,%r9,.Lslow_next_acc_notonbb /* Found a zero in loaded bytes
-> Prepare vr. */
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. */
END(STRSPN_Z13)
# if ! HAVE_STRSPN_IFUNC
strong_alias (STRSPN_Z13, strspn)
# endif
# if ! HAVE_STRSPN_C && defined SHARED && IS_IN (libc)
strong_alias (STRSPN_Z13, __GI_strspn)
# endif
#endif /* HAVE_STRSPN_Z13 */
|
