1/* Vector optimized 32/64 bit S/390 version of strcmp.
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-strcmp.h>
20#if HAVE_STRCMP_Z13
21
22# include "sysdep.h"
23# include "asm-syntax.h"
24
25	.text
26
27/* int strcmp (const char *s1, const char *s2)
28   Compare two strings
29
30   Register usage:
31   -r1=loaded byte count s1
32   -r2=s1
33   -r3=s2
34   -r4=loaded byte coutn s2, tmp
35   -r5=current_len
36   -v16=part of s1
37   -v17=part of s2
38   -v18=index of unequal
39*/
40ENTRY(STRCMP_Z13)
41	.machine "z13"
42	.machinemode "zarch_nohighgprs"
43
44	lghi	%r5,0		/* current_len = 0.  */
45
46.Lloop:
47	vlbb	%v16,0(%r5,%r2),6 /* Load s1 to block boundary.  */
48	vlbb	%v17,0(%r5,%r3),6 /* Load s2 to block boundary.  */
49	lcbb	%r1,0(%r5,%r2),6 /* Get loaded byte count of s1.  */
50	jo	.Llt16_1	/* Jump away if vr is not fully loaded.  */
51	lcbb	%r4,0(%r5,%r3),6
52	jo	.Llt16_2	/* Jump away if vr is not fully loaded.  */
53	/* Both vrs are fully loaded.  */
54	aghi	%r5,16
55	vfenezbs %v18,%v16,%v17	/* Compare not equal with zero search.  */
56	jno	.Lfound
57
58	vlbb	%v16,0(%r5,%r2),6
59	vlbb	%v17,0(%r5,%r3),6
60	lcbb	%r1,0(%r5,%r2),6
61	jo	.Llt16_1
62	lcbb	%r4,0(%r5,%r3),6
63	jo	.Llt16_2
64	aghi	%r5,16
65	vfenezbs %v18,%v16,%v17
66	jno	.Lfound
67
68	vlbb	%v16,0(%r5,%r2),6
69	vlbb	%v17,0(%r5,%r3),6
70	lcbb	%r1,0(%r5,%r2),6
71	jo	.Llt16_1
72	lcbb	%r4,0(%r5,%r3),6
73	jo	.Llt16_2
74	aghi	%r5,16
75	vfenezbs %v18,%v16,%v17
76	jno	.Lfound
77
78	vlbb	%v16,0(%r5,%r2),6
79	vlbb	%v17,0(%r5,%r3),6
80	lcbb	%r1,0(%r5,%r2),6
81	jo	.Llt16_1
82	lcbb	%r4,0(%r5,%r3),6
83	jo	.Llt16_2
84	aghi	%r5,16
85	vfenezbs %v18,%v16,%v17
86	jno	.Lfound
87	j	.Lloop
88
89.Llt16_1:
90	lcbb	%r4,0(%r5,%r3),6 /* Get loaded byte count of s2.  */
91.Llt16_2:
92	clr	%r1,%r4
93	locrh	%r1,%r4		/* Get minimum of bytes loaded in s1/2.  */
94	algfr	%r5,%r1		/* Add smallest loaded bytes to current_len.  */
95	vfenezbs %v18,%v16,%v17	/* Compare not equal with zero search.  */
96	vlgvb	%r4,%v18,7	/* Get not equal index or 16 if all equal.  */
97	clrjl	%r4,%r1,.Lfound /* Jump away if miscompare is within loaded
98				    bytes.  */
99	j	.Lloop
100
101.Lfound:
102	je	.Lend_equal
103	lghi	%r2,1
104	lghi	%r1,-1
105	locgrl	%r2,%r1
106	br	%r14
107.Lend_equal:
108	lghi	%r2,0
109	br	%r14
110END(STRCMP_Z13)
111
112# if ! HAVE_STRCMP_IFUNC
113strong_alias (STRCMP_Z13, strcmp)
114# endif
115
116# if ! HAVE_STRCMP_Z900_G5 && defined SHARED && IS_IN (libc)
117strong_alias (STRCMP_Z13, __GI_strcmp)
118# endif
119#endif
120