1/* Vector optimized 32/64 bit S/390 version of wcslen.
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-wcslen.h>
20#if HAVE_WCSLEN_Z13
21
22# include "sysdep.h"
23# include "asm-syntax.h"
24
25	.text
26
27/* size_t wcslen (const wchar_t *s)
28   Returns length of string s.
29
30   Register usage:
31   -r1=bytes to 4k-byte boundary
32   -r2=s
33   -r3=tmp
34   -r4=tmp
35   -r5=current_len and return_value
36   -v16=part of s
37*/
38ENTRY(WCSLEN_Z13)
39	.machine "z13"
40	.machinemode "zarch_nohighgprs"
41
42	vlbb	%v16,0(%r2),6	/* Load s until next 4k-byte boundary.  */
43	lcbb	%r1,0(%r2),6	/* Get bytes to 4k-byte boundary or 16.  */
44
45	tmll	%r2,3		/* Test if s is 4-byte aligned?   */
46	jne	.Lfallback	/* And use common-code variant if not.  */
47
48	vfenezf	%v16,%v16,%v16	/* Find element not equal with zero search.  */
49	vlgvb	%r4,%v16,7	/* Load zero index or 16 if not found.  */
50	clr	%r4,%r1		/* If found zero within loaded bytes?  */
51	locgrl	%r2,%r4		/* Then copy return value.  */
52	jl	.Lend		/* And return.  */
53
54	/* Align s to 16 byte.  */
55	risbgn	%r3,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15.  */
56	lghi	%r5,16		/* current_len = 16.  */
57	slr	%r5,%r3		/* Compute bytes to 16bytes boundary.  */
58
59	/* Find zero in 16byte aligned loop.  */
60.Lloop:
61	vl	%v16,0(%r5,%r2)	/* Load s.  */
62	vfenezfs %v16,%v16,%v16	/* Find element not equal with zero search.  */
63	je	.Lfound		/* Jump away if zero was found.  */
64	vl	%v16,16(%r5,%r2)
65	vfenezfs %v16,%v16,%v16
66	je	.Lfound16
67	vl	%v16,32(%r5,%r2)
68	vfenezfs %v16,%v16,%v16
69	je	.Lfound32
70	vl	%v16,48(%r5,%r2)
71	vfenezfs %v16,%v16,%v16
72	je	.Lfound48
73
74	aghi	%r5,64
75	j	.Lloop		/* No zero found -> loop.  */
76
77.Lfound48:
78	aghi	%r5,16
79.Lfound32:
80	aghi	%r5,16
81.Lfound16:
82	aghi	%r5,16
83.Lfound:
84	vlgvb	%r2,%v16,7	/* Load byte index of zero.  */
85	algr	%r2,%r5
86.Lend:
87	srlg	%r2,%r2,2	/* Convert byte-count to character-count.  */
88	br	%r14
89.Lfallback:
90	jg	WCSLEN_C
91END(WCSLEN_Z13)
92
93# if ! HAVE_WCSLEN_IFUNC
94strong_alias (WCSLEN_Z13, __wcslen)
95weak_alias (__wcslen, wcslen)
96# endif
97#endif
98