summaryrefslogtreecommitdiffstats
path: root/arch/sparc/lib/memscan_64.S
blob: daa96f4b03e6007fbc415a70514f3f56be8a4ef1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/*
 * memscan.S: Optimized memscan for Sparc64.
 *
 * Copyright (C) 1997,1998 Jakub Jelinek (jj@ultra.linux.cz)
 * Copyright (C) 1998 David S. Miller (davem@redhat.com)
 */

	#include <asm/export.h>

#define HI_MAGIC	0x8080808080808080
#define LO_MAGIC	0x0101010101010101
#define ASI_PL		0x88

	.text
	.align	32
	.globl		__memscan_zero, __memscan_generic
	.globl		memscan
	EXPORT_SYMBOL(__memscan_zero)
	EXPORT_SYMBOL(__memscan_generic)

__memscan_zero:
	/* %o0 = bufp, %o1 = size */
	brlez,pn	%o1, szzero
	 andcc		%o0, 7, %g0
	be,pt		%icc, we_are_aligned
	 sethi		%hi(HI_MAGIC), %o4
	ldub		[%o0], %o5
1:	subcc		%o1, 1, %o1
	brz,pn		%o5, 10f
	 add		%o0, 1, %o0

	be,pn		%xcc, szzero
	 andcc		%o0, 7, %g0
	bne,a,pn	%icc, 1b
	 ldub		[%o0], %o5
we_are_aligned:
	ldxa		[%o0] ASI_PL, %o5
	or		%o4, %lo(HI_MAGIC), %o3
	sllx		%o3, 32, %o4
	or		%o4, %o3, %o3

	srlx		%o3, 7, %o2
msloop:
	sub		%o1, 8, %o1
	add		%o0, 8, %o0
	sub		%o5, %o2, %o4
	xor		%o4, %o5, %o4
	andcc		%o4, %o3, %g3
	bne,pn		%xcc, check_bytes
	 srlx		%o4, 32, %g3

	brgz,a,pt	%o1, msloop
	 ldxa		[%o0] ASI_PL, %o5
check_bytes:
	bne,a,pn	%icc, 2f
	 andcc		%o5, 0xff, %g0
	add		%o0, -5, %g2
	ba,pt		%xcc, 3f
	 srlx		%o5, 32, %g7

2:	srlx		%o5, 8, %g7
	be,pn		%icc, 1f
	 add		%o0, -8, %g2
	andcc		%g7, 0xff, %g0
	srlx		%g7, 8, %g7
	be,pn		%icc, 1f
	 inc		%g2
	andcc		%g7, 0xff, %g0

	srlx		%g7, 8, %g7
	be,pn		%icc, 1f
	 inc		%g2
	andcc		%g7, 0xff, %g0
	srlx		%g7, 8, %g7
	be,pn		%icc, 1f
	 inc		%g2
	andcc		%g3, %o3, %g0

	be,a,pn		%icc, 2f
	 mov		%o0, %g2
3:	andcc		%g7, 0xff, %g0
	srlx		%g7, 8, %g7
	be,pn		%icc, 1f
	 inc		%g2
	andcc		%g7, 0xff, %g0
	srlx		%g7, 8, %g7

	be,pn		%icc, 1f
	 inc		%g2
	andcc		%g7, 0xff, %g0
	srlx		%g7, 8, %g7
	be,pn		%icc, 1f
	 inc		%g2
	andcc		%g7, 0xff, %g0
	srlx		%g7, 8, %g7

	be,pn		%icc, 1f
	 inc		%g2
2:	brgz,a,pt	%o1, msloop
	 ldxa		[%o0] ASI_PL, %o5
	inc		%g2
1:	add		%o0, %o1, %o0
	cmp		%g2, %o0
	retl

	 movle		%xcc, %g2, %o0
10:	retl
	 sub		%o0, 1, %o0
szzero:	retl
	 nop

memscan:
__memscan_generic:
	/* %o0 = addr, %o1 = c, %o2 = size */
	brz,pn		%o2, 3f
	 add		%o0, %o2, %o3
	ldub		[%o0], %o5
	sub		%g0, %o2, %o4
1:
	cmp		%o5, %o1
	be,pn		%icc, 2f
	 addcc		%o4, 1, %o4
	bne,a,pt 	%xcc, 1b
	 ldub		[%o3 + %o4], %o5
	retl
	/* The delay slot is the same as the next insn, this is just to make it look more awful */
2:
	 add		%o3, %o4, %o0
	retl
	 sub		%o0, 1, %o0
3:
	retl
	 nop