1 /* Vector optimized 32/64 bit S/390 version of strlen.
2 Copyright (C) 2015-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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.
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.
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/>. */
19 #include <ifunc-strlen.h>
23 # include "asm-syntax.h"
27 /* size_t strlen (const char *s)
28 Returns length of string s.
31 -r1=bytes to 4k-byte boundary
35 -r5=current_len and return_value
40 .machinemode "zarch_nohighgprs"
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. */
45 vfenezb %v16,%v16,%v16 /* Find element not equal with zero search. */
46 vlgvb %r4,%v16,7 /* Load zero index or 16 if not found. */
47 clr %r4,%r1 /* If found zero within loaded bytes? */
48 locgrl %r2,%r4 /* Then copy return value. */
49 blr %r14 /* And return. */
51 /* Align s to 16 byte. */
52 risbgn %r3,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
53 lghi %r5,16 /* current_len = 16. */
54 slr %r5,%r3 /* Compute bytes to 16bytes boundary. */
56 /* Find zero in 16 byte aligned loop. */
58 vl %v16,0(%r5,%r2) /* Load s. */
59 vfenezbs %v16,%v16,%v16 /* Find element not equal with zero search. */
60 je .Lfound /* Jump away if zero was found. */
62 vfenezbs %v16,%v16,%v16
65 vfenezbs %v16,%v16,%v16
68 vfenezbs %v16,%v16,%v16
72 j .Lloop /* No zero found -> loop. */
81 vlgvb %r2,%v16,7 /* Load byte index of zero. */
86 # if ! HAVE_STRLEN_IFUNC
87 strong_alias (STRLEN_Z13, strlen)
90 # if ! HAVE_STRLEN_C && defined SHARED && IS_IN (libc)
91 strong_alias (STRLEN_Z13, __GI_strlen)