1/* Vector optimized 32/64 bit S/390 version of strchrnul.
2 Copyright (C) 2015-2022 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <ifunc-strchrnul.h>
20
21#if HAVE_STRCHRNUL_Z13
22
23# include "sysdep.h"
24# include "asm-syntax.h"
25
26 .text
27
28/* char *strchrnul (const char *s, int c)
29 Returns pointer to first c or to \0 if c not found.
30
31 Register usage:
32 -r1=tmp
33 -r2=s and return pointer
34 -r3=c
35 -r4=tmp
36 -r5=current_len
37 -v16=part of s
38 -v18=vector with c replicated in every byte
39*/
40ENTRY(STRCHRNUL_Z13)
41 .machine "z13"
42 .machinemode "zarch_nohighgprs"
43
44 vlbb %v16,0(%r2),6 /* Load s until next 4k-byte boundary. */
45 lcbb %r1,0(%r2),6 /* Get bytes to 4k-byte boundary or 16. */
46
47 lghi %r5,0 /* current_len = 0. */
48
49 vlvgb %v18,%r3,0 /* Generate vector which elements are all c.
50 If c > 255, c will be truncated. */
51 vrepb %v18,%v18,0
52
53 vfeezbs %v16,%v16,%v18 /* Find element equal with zero search. */
54 vlgvb %r4,%v16,7 /* Load byte index of character or zero. */
55 clrjl %r4,%r1,.Lfound /* Return if c/zero is in loaded bytes. */
56
57 /* Align s to 16 byte. */
58 risbgn %r4,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
59 lghi %r5,16 /* current_len = 16. */
60 slr %r5,%r4 /* Compute bytes to 16bytes boundary. */
61
62 /* Find c/zero in 16byte aligned loop */
63.Lloop:
64 vl %v16,0(%r5,%r2) /* Load s */
65 vfeezbs %v16,%v16,%v18 /* Find element equal with zero search. */
66 jno .Lfound /* Found c/zero (cc=0|1|2). */
67 vl %v16,16(%r5,%r2)
68 vfeezbs %v16,%v16,%v18
69 jno .Lfound16
70 vl %v16,32(%r5,%r2)
71 vfeezbs %v16,%v16,%v18
72 jno .Lfound32
73 vl %v16,48(%r5,%r2)
74 vfeezbs %v16,%v16,%v18
75 jno .Lfound48
76
77 aghi %r5,64
78 j .Lloop /* No character and no zero -> loop. */
79
80 /* Found character or zero */
81.Lfound48:
82 aghi %r5,16
83.Lfound32:
84 aghi %r5,16
85.Lfound16:
86 aghi %r5,16
87.Lfound:
88 vlgvb %r1,%v16,7 /* Load byte index of character. */
89 algr %r5,%r1
90 la %r2,0(%r5,%r2) /* Return pointer to character. */
91
92.Lend:
93 br %r14
94END(STRCHRNUL_Z13)
95
96# if ! HAVE_STRCHRNUL_IFUNC
97strong_alias (STRCHRNUL_Z13, __strchrnul)
98weak_alias (__strchrnul, strchrnul)
99# endif
100
101#endif /* HAVE_STRCHRNUL_Z13 */
102

source code of glibc/sysdeps/s390/strchrnul-vx.S