1/* Vector optimized 32/64 bit S/390 version of strcat.
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-strcat.h>
20#if HAVE_STRCAT_Z13
21
22# include "sysdep.h"
23# include "asm-syntax.h"
24
25 .text
26
27/* char * strcat (const char *dest, const char *src)
28 Concatenate two strings.
29
30 Register usage:
31 -r0=saved dest pointer for return
32 -r1=tmp
33 -r2=dest
34 -r3=src
35 -r4=tmp
36 -r5=current_len
37 -v16=part of src
38 -v17=index of zero
39 -v18=part of src
40*/
41ENTRY(STRCAT_Z13)
42 .machine "z13"
43 .machinemode "zarch_nohighgprs"
44
45 lgr %r0,%r2 /* Save destination pointer for return. */
46
47 /* STRLEN
48 r1 = loaded bytes (tmp)
49 r4 = zero byte index (tmp)
50 r2 = dst
51 */
52 vlbb %v16,0(%r2),6 /* Load s until next 4k-byte boundary. */
53 lcbb %r1,0(%r2),6 /* Get bytes to 4k-byte boundary or 16. */
54
55 vfenezb %v16,%v16,%v16 /* Find element not equal with zero search. */
56 vlgvb %r5,%v16,7 /* Load zero index or 16 if not found. */
57 clrjl %r5,%r1,.Llen_end /* Found zero within loaded bytes, end. */
58
59 /* Align s to 16 byte. */
60 risbgn %r1,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
61 lghi %r5,16 /* current_len = 16. */
62 slr %r5,%r1 /* Compute bytes to 16bytes boundary. */
63
64 /* Find zero in 16byte aligned loop. */
65.Llen_loop:
66 vl %v16,0(%r5,%r2) /* Load s. */
67 vfenezbs %v16,%v16,%v16 /* Find element not equal with zero search. */
68 je .Llen_found /* Jump away if zero was found. */
69 vl %v16,16(%r5,%r2)
70 vfenezbs %v16,%v16,%v16
71 je .Llen_found16
72 vl %v16,32(%r5,%r2)
73 vfenezbs %v16,%v16,%v16
74 je .Llen_found32
75 vl %v16,48(%r5,%r2)
76 vfenezbs %v16,%v16,%v16
77 je .Llen_found48
78
79 aghi %r5,64
80 j .Llen_loop /* No zero -> loop. */
81
82.Llen_found48:
83 aghi %r5,16
84.Llen_found32:
85 aghi %r5,16
86.Llen_found16:
87 aghi %r5,16
88.Llen_found:
89 vlgvb %r4,%v16,7 /* Load byte index of zero. */
90 algr %r5,%r4
91
92.Llen_end:
93 /* STRCPY
94 %r1 = loaded bytes (tmp)
95 %r4 = zero byte index (tmp)
96 %r3 = curr src pointer
97 %r2 = curr dst pointer
98 */
99 la %r2,0(%r5,%r2) /* strcpy at end of dst-string. */
100
101 vlbb %v16,0(%r3),6 /* Load s until next 4k-byte boundary. */
102 lcbb %r1,0(%r3),6 /* Get bytes to 4k-byte boundary or 16. */
103
104 vfenezb %v17,%v16,%v16 /* Find element not equal with zero search. */
105 vlgvb %r5,%v17,7 /* Load zero index or 16 if not found. */
106 clrjl %r5,%r1,.Lcpy_found_align /* If found zero within loaded bytes,
107 copy bytes before and return. */
108
109 /* Align s to 16 byte. */
110 risbgn %r4,%r3,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
111 lghi %r5,15 /* current_len = 15. */
112 slr %r5,%r4 /* Compute highest index to 16byte boundary. */
113
114 vstl %v16,%r5,0(%r2) /* Copy loaded characters - no zero. */
115 ahi %r5,1 /* Start loop at next character. */
116
117 /* Find zero in 16byte aligned loop. */
118.Lcpy_loop:
119 vl %v16,0(%r5,%r3) /* Load s. */
120 vfenezbs %v17,%v16,%v16 /* Find element not equal with zero search. */
121 je .Lcpy_found_v16_0 /* Jump away if zero was found. */
122 vl %v18,16(%r5,%r3)/* Load next part of s. */
123 vst %v16,0(%r5,%r2) /* Store previous part without zero to dst. */
124 vfenezbs %v17,%v18,%v18
125 je .Lcpy_found_v18_16
126 vl %v16,32(%r5,%r3)
127 vst %v18,16(%r5,%r2)
128 vfenezbs %v17,%v16,%v16
129 je .Lcpy_found_v16_32
130 vl %v18,48(%r5,%r3)
131 vst %v16,32(%r5,%r2)
132 vfenezbs %v17,%v18,%v18
133 je .Lcpy_found_v18_48
134 vst %v18,48(%r5,%r2)
135
136 aghi %r5,64
137 j .Lcpy_loop /* No zero -> loop. */
138
139.Lcpy_found_v16_32:
140 aghi %r5,32
141.Lcpy_found_v16_0:
142 la %r4,0(%r5,%r2)
143 vlgvb %r1,%v17,7 /* Load byte index of zero. */
144 vstl %v16,%r1,0(%r4) /* Copy characters including zero. */
145 lgr %r2,%r0 /* Load saved dest-ptr. */
146 br %r14
147
148.Lcpy_found_v18_48:
149 aghi %r5,32
150.Lcpy_found_v18_16:
151 la %r4,16(%r5,%r2)
152 vlgvb %r1,%v17,7 /* Load byte index of zero. */
153 vstl %v18,%r1,0(%r4) /* Copy characters including zero. */
154 lgr %r2,%r0 /* Load saved dest-ptr. */
155 br %r14
156
157.Lcpy_found_align:
158 vstl %v16,%r5,0(%r2) /* Copy characters including zero. */
159 lgr %r2,%r0 /* Load saved dest-ptr. */
160 br %r14
161END(STRCAT_Z13)
162
163# if ! HAVE_STRCAT_IFUNC
164strong_alias (STRCAT_Z13, strcat)
165# endif
166
167# if ! HAVE_STRCAT_C && defined SHARED && IS_IN (libc)
168strong_alias (STRCAT_Z13, __GI_strcat)
169# endif
170#endif
171

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