1/* Vector optimized 32/64 bit S/390 version of strcpy.
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-strcpy.h>
20#include "sysdep.h"
21#include "asm-syntax.h"
22
23 .text
24
25#if HAVE_STRCPY_Z13
26/* char * strcpy (const char *dest, const char *src)
27 Copy string src to dest.
28
29 Register usage:
30 -r1=tmp
31 -r2=dest and return_value
32 -r3=src
33 -r4=tmp
34 -r5=current_len
35 -v16=part of src
36 -v17=index of zero
37 -v18=part of src
38*/
39ENTRY(STRCPY_Z13)
40 .machine "z13"
41 .machinemode "zarch_nohighgprs"
42
43 vlbb %v16,0(%r3),6 /* Load s until next 4k-byte boundary. */
44 lcbb %r1,0(%r3),6 /* Get bytes to 4k-byte boundary or 16. */
45
46 vfenezb %v17,%v16,%v16 /* Find element not equal with zero search. */
47 vlgvb %r5,%v17,7 /* Load zero index or 16 if not found. */
48 clrjl %r5,%r1,.Lfound_align /* If found zero within loaded bytes,
49 copy bytes before and return. */
50
51 /* Align s to 16 byte. */
52 risbgn %r4,%r3,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
53 lghi %r5,15 /* current_len = 15. */
54 slr %r5,%r4 /* Compute highest index to 16byte boundary. */
55
56 vstl %v16,%r5,0(%r2) /* Copy loaded characters - no zero. */
57 ahi %r5,1 /* Start loop at next character. */
58
59 /* Find zero in 16byte aligned loop. */
60.Lloop:
61 vl %v16,0(%r5,%r3) /* Load s. */
62 vfenezbs %v17,%v16,%v16 /* Find element not equal with zero search. */
63 je .Lfound_v16_0 /* Jump away if zero was found. */
64 vl %v18,16(%r5,%r3)/* Load next part of s. */
65 vst %v16,0(%r5,%r2) /* Store previous part without zero to dst. */
66 vfenezbs %v17,%v18,%v18
67 je .Lfound_v18_16
68 vl %v16,32(%r5,%r3)
69 vst %v18,16(%r5,%r2)
70 vfenezbs %v17,%v16,%v16
71 je .Lfound_v16_32
72 vl %v18,48(%r5,%r3)
73 vst %v16,32(%r5,%r2)
74 vfenezbs %v17,%v18,%v18
75 je .Lfound_v18_48
76 vst %v18,48(%r5,%r2)
77
78 aghi %r5,64
79 j .Lloop /* No zero found -> loop. */
80
81.Lfound_v16_32:
82 aghi %r5,32
83.Lfound_v16_0:
84 la %r3,0(%r5,%r2)
85 vlgvb %r4,%v17,7 /* Load byte index of zero. */
86 vstl %v16,%r4,0(%r3) /* Store characters including zero. */
87 br %r14
88
89.Lfound_v18_48:
90 aghi %r5,32
91.Lfound_v18_16:
92 la %r3,16(%r5,%r2)
93 vlgvb %r4,%v17,7 /* Load byte index of zero. */
94 vstl %v18,%r4,0(%r3) /* Store characters including zero. */
95 br %r14
96
97.Lfound_align:
98 vstl %v16,%r5,0(%r2) /* Copy characters including zero. */
99 br %r14
100END(STRCPY_Z13)
101
102# if ! HAVE_STRCPY_IFUNC
103strong_alias (STRCPY_Z13, strcpy)
104# endif
105
106# if ! HAVE_STRCPY_Z900_G5 && defined SHARED && IS_IN (libc)
107strong_alias (STRCPY_Z13, __GI_strcpy)
108# endif
109#endif
110

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