projects/linux·blob master · refs

149 lines · 2.4 KiB

1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4 */
5
6#include <linux/linkage.h>
7
8#ifdef __LITTLE_ENDIAN__
9#define WORD2 r2
10#define SHIFT r3
11#else /* BIG ENDIAN */
12#define WORD2 r3
13#define SHIFT r2
14#endif
15
16ENTRY_CFI(memcmp)
17 or r12,r0,r1
18 asl_s r12,r12,30
19 sub r3,r2,1
20 brls r2,r12,.Lbytewise
21 ld r4,[r0,0]
22 ld r5,[r1,0]
23 lsr.f lp_count,r3,3
24#ifdef CONFIG_ISA_ARCV2
25 /* In ARCv2 a branch can't be the last instruction in a zero overhead
26 * loop.
27 * So we move the branch to the start of the loop, duplicate it
28 * after the end, and set up r12 so that the branch isn't taken
29 * initially.
30 */
31 mov_s r12,WORD2
32 lpne .Loop_end
33 brne WORD2,r12,.Lodd
34 ld WORD2,[r0,4]
35#else
36 lpne .Loop_end
37 ld_s WORD2,[r0,4]
38#endif
39 ld_s r12,[r1,4]
40 brne r4,r5,.Leven
41 ld.a r4,[r0,8]
42 ld.a r5,[r1,8]
43#ifdef CONFIG_ISA_ARCV2
44.Loop_end:
45 brne WORD2,r12,.Lodd
46#else
47 brne WORD2,r12,.Lodd
48.Loop_end:
49#endif
50 asl_s SHIFT,SHIFT,3
51 bhs_s .Last_cmp
52 brne r4,r5,.Leven
53 ld r4,[r0,4]
54 ld r5,[r1,4]
55#ifdef __LITTLE_ENDIAN__
56 nop_s
57 ; one more load latency cycle
58.Last_cmp:
59 xor r0,r4,r5
60 bset r0,r0,SHIFT
61 sub_s r1,r0,1
62 bic_s r1,r1,r0
63 norm r1,r1
64 b.d .Leven_cmp
65 and r1,r1,24
66.Leven:
67 xor r0,r4,r5
68 sub_s r1,r0,1
69 bic_s r1,r1,r0
70 norm r1,r1
71 ; slow track insn
72 and r1,r1,24
73.Leven_cmp:
74 asl r2,r4,r1
75 asl r12,r5,r1
76 lsr_s r2,r2,1
77 lsr_s r12,r12,1
78 j_s.d [blink]
79 sub r0,r2,r12
80 .balign 4
81.Lodd:
82 xor r0,WORD2,r12
83 sub_s r1,r0,1
84 bic_s r1,r1,r0
85 norm r1,r1
86 ; slow track insn
87 and r1,r1,24
88 asl_s r2,r2,r1
89 asl_s r12,r12,r1
90 lsr_s r2,r2,1
91 lsr_s r12,r12,1
92 j_s.d [blink]
93 sub r0,r2,r12
94#else /* BIG ENDIAN */
95.Last_cmp:
96 neg_s SHIFT,SHIFT
97 lsr r4,r4,SHIFT
98 lsr r5,r5,SHIFT
99 ; slow track insn
100.Leven:
101 sub.f r0,r4,r5
102 mov.ne r0,1
103 j_s.d [blink]
104 bset.cs r0,r0,31
105.Lodd:
106 cmp_s WORD2,r12
107 mov_s r0,1
108 j_s.d [blink]
109 bset.cs r0,r0,31
110#endif /* ENDIAN */
111 .balign 4
112.Lbytewise:
113 breq r2,0,.Lnil
114 ldb r4,[r0,0]
115 ldb r5,[r1,0]
116 lsr.f lp_count,r3
117#ifdef CONFIG_ISA_ARCV2
118 mov r12,r3
119 lpne .Lbyte_end
120 brne r3,r12,.Lbyte_odd
121#else
122 lpne .Lbyte_end
123#endif
124 ldb_s r3,[r0,1]
125 ldb r12,[r1,1]
126 brne r4,r5,.Lbyte_even
127 ldb.a r4,[r0,2]
128 ldb.a r5,[r1,2]
129#ifdef CONFIG_ISA_ARCV2
130.Lbyte_end:
131 brne r3,r12,.Lbyte_odd
132#else
133 brne r3,r12,.Lbyte_odd
134.Lbyte_end:
135#endif
136 bcc .Lbyte_even
137 brne r4,r5,.Lbyte_even
138 ldb_s r3,[r0,1]
139 ldb_s r12,[r1,1]
140.Lbyte_odd:
141 j_s.d [blink]
142 sub r0,r3,r12
143.Lbyte_even:
144 j_s.d [blink]
145 sub r0,r4,r5
146.Lnil:
147 j_s.d [blink]
148 mov r0,0
149END_CFI(memcmp)