1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Sy
4 */
5
6 /* ARC700 has a relatively long pipeline and b
7 to avoid branches that are hard to predict.
8 presence of the norm instruction makes it e
9 words branch-free. */
10
11 #include <linux/linkage.h>
12
13 ENTRY_CFI(strchr)
14 extb_s r1,r1
15 asl r5,r1,8
16 bmsk r2,r0,1
17 or r5,r5,r1
18 mov_s r3,0x01010101
19 breq.d r2,r0,.Laligned
20 asl r4,r5,16
21 sub_s r0,r0,r2
22 asl r7,r2,3
23 ld_s r2,[r0]
24 #ifdef __LITTLE_ENDIAN__
25 asl r7,r3,r7
26 #else
27 lsr r7,r3,r7
28 #endif
29 or r5,r5,r4
30 ror r4,r3
31 sub r12,r2,r7
32 bic_s r12,r12,r2
33 and r12,r12,r4
34 brne.d r12,0,.Lfound0_ua
35 xor r6,r2,r5
36 ld.a r2,[r0,4]
37 sub r12,r6,r7
38 bic r12,r12,r6
39 #ifdef __LITTLE_ENDIAN__
40 and r7,r12,r4
41 breq r7,0,.Loop ; For speed, we wan
42 b .Lfound_char ; Likewise this o
43 #else
44 and r12,r12,r4
45 breq r12,0,.Loop ; For speed, we wa
46 lsr_s r12,r12,7
47 bic r2,r7,r6
48 b.d .Lfound_char_b
49 and_s r2,r2,r12
50 #endif
51 ; /* We require this code address to be unalig
52 .Laligned:
53 ld_s r2,[r0]
54 or r5,r5,r4
55 ror r4,r3
56 ; /* ... so that this code address is aligned,
57 .Loop:
58 sub r12,r2,r3
59 bic_s r12,r12,r2
60 and r12,r12,r4
61 brne.d r12,0,.Lfound0
62 xor r6,r2,r5
63 ld.a r2,[r0,4]
64 sub r12,r6,r3
65 bic r12,r12,r6
66 and r7,r12,r4
67 breq r7,0,.Loop /* ... so that this
68 ; Found searched-for character. r0 ha
69 #ifdef __LITTLE_ENDIAN__
70 /* We only need the information about the firs
71 (i.e. the least significant matching byte)
72 hence there is no problem with carry effect
73 .Lfound_char:
74 sub r3,r7,1
75 bic r3,r3,r7
76 norm r2,r3
77 sub_s r0,r0,1
78 asr_s r2,r2,3
79 j.d [blink]
80 sub_s r0,r0,r2
81
82 .balign 4
83 .Lfound0_ua:
84 mov r3,r7
85 .Lfound0:
86 sub r3,r6,r3
87 bic r3,r3,r6
88 and r2,r3,r4
89 or_s r12,r12,r2
90 sub_s r3,r12,1
91 bic_s r3,r3,r12
92 norm r3,r3
93 add_s r0,r0,3
94 asr_s r12,r3,3
95 asl.f 0,r2,r3
96 sub_s r0,r0,r12
97 j_s.d [blink]
98 mov.pl r0,0
99 #else /* BIG ENDIAN */
100 .Lfound_char:
101 lsr r7,r7,7
102
103 bic r2,r7,r6
104 .Lfound_char_b:
105 norm r2,r2
106 sub_s r0,r0,4
107 asr_s r2,r2,3
108 j.d [blink]
109 add_s r0,r0,r2
110
111 .Lfound0_ua:
112 mov_s r3,r7
113 .Lfound0:
114 asl_s r2,r2,7
115 or r7,r6,r4
116 bic_s r12,r12,r2
117 sub r2,r7,r3
118 or r2,r2,r6
119 bic r12,r2,r12
120 bic.f r3,r4,r12
121 norm r3,r3
122
123 add.pl r3,r3,1
124 asr_s r12,r3,3
125 asl.f 0,r2,r3
126 add_s r0,r0,r12
127 j_s.d [blink]
128 mov.mi r0,0
129 #endif /* ENDIAN */
130 END_CFI(strchr)
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