1/* Optimized strcasecmp implementation for PowerPC32.
2   Copyright (C) 2011-2021 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 <sysdep.h>
20#include <locale-defines.h>
21
22/* int [r3] strcasecmp (const char *s1 [r3], const char *s2 [r4] )
23
24   or if defined USE_IN_EXTENDED_LOCALE_MODEL:
25
26   int [r3] strcasecmp_l (const char *s1 [r3], const char *s2 [r4],
27                          locale_t loc [r5]) */
28
29#ifndef STRCMP
30# define __STRCMP __strcasecmp
31# define STRCMP   strcasecmp
32#endif
33
34ENTRY (__STRCMP)
35
36#define rRTN	r3	/* Return value */
37#define rSTR1	r5	/* 1st string */
38#define rSTR2	r4	/* 2nd string */
39#define rLOCARG	r5	/* 3rd argument: locale_t */
40#define rCHAR1	r6	/* Byte read from 1st string */
41#define rCHAR2	r7	/* Byte read from 2nd string */
42#define rADDR1	r8	/* Address of tolower(rCHAR1) */
43#define rADDR2	r12	/* Address of tolower(rCHAR2) */
44#define rLWR1	r8	/* Byte tolower(rCHAR1) */
45#define rLWR2	r12	/* Byte tolower(rCHAR2) */
46#define rTMP	r0
47#define rGOT	r9	/* Address of the Global Offset Table */
48#define rLOC	r11	/* Default locale address */
49
50	cmpw    cr7, r3, r4
51#ifndef USE_IN_EXTENDED_LOCALE_MODEL
52# ifdef SHARED
53	mflr	rTMP
54	bcl	20,31,.L1
55.L1:	mflr	rGOT
56	addis	rGOT, rGOT, _GLOBAL_OFFSET_TABLE_-.L1@ha
57	addi 	rGOT, rGOT, _GLOBAL_OFFSET_TABLE_-.L1@l
58	lwz	rLOC, __libc_tsd_LOCALE@got@tprel(rGOT)
59	add 	rLOC, rLOC, __libc_tsd_LOCALE@tls
60	lwz	rLOC, 0(rLOC)
61	mtlr	rTMP
62# else
63	lis	rTMP,_GLOBAL_OFFSET_TABLE_@ha
64	la	rLOC,_GLOBAL_OFFSET_TABLE_@l(rTMP)
65	lwz	rLOC, __libc_tsd_LOCALE@got@tprel(rGOT)
66	add	rLOC, rLOC, __libc_tsd_LOCALE@tls
67	lwz	rLOC, 0(rLOC)
68# endif /* SHARED */
69#else
70	mr	rLOC, rLOCARG
71#endif
72	mr	rSTR1, rRTN
73	lwz	rLOC, LOCALE_CTYPE_TOLOWER(rLOC)
74	li	rRTN, 0
75	beqlr	cr7
76
77	/* Unrolling loop for POWER: loads are done with 'lbz' plus
78	offset and string descriptors are only updated in the end
79	of loop unrolling. */
80
81L(loop):
82	lbz	rCHAR1, 0(rSTR1)	/* Load char from s1 */
83	lbz	rCHAR2, 0(rSTR2)	/* Load char from s2 */
84	sldi	rADDR1, rCHAR1, 2	/* Calculate address for tolower(*s1) */
85	sldi	rADDR2, rCHAR2, 2	/* Calculate address for tolower(*s2) */
86	lwzx	rLWR1, rLOC, rADDR1	/* Load tolower(*s1) */
87	lwzx	rLWR2, rLOC, rADDR2	/* Load tolower(*s2) */
88	cmpwi	cr7, rCHAR1, 0		/* *s1 == '\0' ? */
89	subf.	r3, rLWR2, rLWR1
90	bnelr
91	beqlr	cr7
92	lbz	rCHAR1, 1(rSTR1)
93	lbz	rCHAR2, 1(rSTR2)
94	sldi	rADDR1, rCHAR1, 2
95	sldi	rADDR2, rCHAR2, 2
96	lwzx	rLWR1, rLOC, rADDR1
97	lwzx	rLWR2, rLOC, rADDR2
98	cmpwi	cr7, rCHAR1, 0
99	subf.	r3, rLWR2, rLWR1
100	bnelr
101	beqlr	cr7
102	lbz	rCHAR1, 2(rSTR1)
103	lbz	rCHAR2, 2(rSTR2)
104	sldi	rADDR1, rCHAR1, 2
105	sldi	rADDR2, rCHAR2, 2
106	lwzx	rLWR1, rLOC, rADDR1
107	lwzx	rLWR2, rLOC, rADDR2
108	cmpwi	cr7, rCHAR1, 0
109	subf.	r3, rLWR2, rLWR1
110	bnelr
111	beqlr	cr7
112	lbz	rCHAR1, 3(rSTR1)
113	lbz	rCHAR2, 3(rSTR2)
114	/* Increment both string descriptors */
115	addi	rSTR1, rSTR1, 4
116	addi	rSTR2, rSTR2, 4
117	sldi	rADDR1, rCHAR1, 2
118	sldi	rADDR2, rCHAR2, 2
119	lwzx	rLWR1, rLOC, rADDR1
120	lwzx	rLWR2, rLOC, rADDR2
121	cmpwi	cr7, rCHAR1, 0
122	subf.	r3, rLWR2, rLWR1
123	bnelr
124	bne	cr7,L(loop)
125	blr
126END (__STRCMP)
127
128weak_alias (__STRCMP, STRCMP)
129libc_hidden_builtin_def (__STRCMP)
130