summaryrefslogtreecommitdiffstats
path: root/arch/arc/lib/memcpy-archs.S
blob: 1b2b3acfed52df6f1fb0aad58fa834d3d689482d (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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
/*
 * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/linkage.h>

#ifdef __LITTLE_ENDIAN__
# define SHIFT_1(RX,RY,IMM)	asl	RX, RY, IMM	; <<
# define SHIFT_2(RX,RY,IMM)	lsr	RX, RY, IMM	; >>
# define MERGE_1(RX,RY,IMM)	asl	RX, RY, IMM
# define MERGE_2(RX,RY,IMM)
# define EXTRACT_1(RX,RY,IMM)	and	RX, RY, 0xFFFF
# define EXTRACT_2(RX,RY,IMM)	lsr	RX, RY, IMM
#else
# define SHIFT_1(RX,RY,IMM)	lsr	RX, RY, IMM	; >>
# define SHIFT_2(RX,RY,IMM)	asl	RX, RY, IMM	; <<
# define MERGE_1(RX,RY,IMM)	asl	RX, RY, IMM	; <<
# define MERGE_2(RX,RY,IMM)	asl	RX, RY, IMM	; <<
# define EXTRACT_1(RX,RY,IMM)	lsr	RX, RY, IMM
# define EXTRACT_2(RX,RY,IMM)	lsr	RX, RY, 0x08
#endif

#ifdef CONFIG_ARC_HAS_LL64
# define PREFETCH_READ(RX)	prefetch    [RX, 56]
# define PREFETCH_WRITE(RX)	prefetchw   [RX, 64]
# define LOADX(DST,RX)		ldd.ab	DST, [RX, 8]
# define STOREX(SRC,RX)		std.ab	SRC, [RX, 8]
# define ZOLSHFT		5
# define ZOLAND			0x1F
#else
# define PREFETCH_READ(RX)	prefetch    [RX, 28]
# define PREFETCH_WRITE(RX)	prefetchw   [RX, 32]
# define LOADX(DST,RX)		ld.ab	DST, [RX, 4]
# define STOREX(SRC,RX)		st.ab	SRC, [RX, 4]
# define ZOLSHFT		4
# define ZOLAND			0xF
#endif

ENTRY(memcpy)
	prefetch [r1]		; Prefetch the read location
	prefetchw [r0]		; Prefetch the write location
	mov.f	0, r2
;;; if size is zero
	jz.d	[blink]
	mov	r3, r0		; don;t clobber ret val

;;; if size <= 8
	cmp	r2, 8
	bls.d	@smallchunk
	mov.f	lp_count, r2

	and.f	r4, r0, 0x03
	rsub	lp_count, r4, 4
	lpnz	@aligndestination
	;; LOOP BEGIN
	ldb.ab	r5, [r1,1]
	sub	r2, r2, 1
	stb.ab	r5, [r3,1]
aligndestination:

;;; Check the alignment of the source
	and.f	r4, r1, 0x03
	bnz.d	@sourceunaligned

;;; CASE 0: Both source and destination are 32bit aligned
;;; Convert len to Dwords, unfold x4
	lsr.f	lp_count, r2, ZOLSHFT
	lpnz	@copy32_64bytes
	;; LOOP START
	LOADX (r6, r1)
	PREFETCH_READ (r1)
	PREFETCH_WRITE (r3)
	LOADX (r8, r1)
	LOADX (r10, r1)
	LOADX (r4, r1)
	STOREX (r6, r3)
	STOREX (r8, r3)
	STOREX (r10, r3)
	STOREX (r4, r3)
copy32_64bytes:

	and.f	lp_count, r2, ZOLAND ;Last remaining 31 bytes
smallchunk:
	lpnz	@copyremainingbytes
	;; LOOP START
	ldb.ab	r5, [r1,1]
	stb.ab	r5, [r3,1]
copyremainingbytes:

	j	[blink]
;;; END CASE 0

sourceunaligned:
	cmp	r4, 2
	beq.d	@unalignedOffby2
	sub	r2, r2, 1

	bhi.d	@unalignedOffby3
	ldb.ab	r5, [r1, 1]

;;; CASE 1: The source is unaligned, off by 1
	;; Hence I need to read 1 byte for a 16bit alignment
	;; and 2bytes to reach 32bit alignment
	ldh.ab	r6, [r1, 2]
	sub	r2, r2, 2
	;; Convert to words, unfold x2
	lsr.f	lp_count, r2, 3
	MERGE_1 (r6, r6, 8)
	MERGE_2 (r5, r5, 24)
	or	r5, r5, r6

	;; Both src and dst are aligned
	lpnz	@copy8bytes_1
	;; LOOP START
	ld.ab	r6, [r1, 4]
	prefetch [r1, 28]	;Prefetch the next read location
	ld.ab	r8, [r1,4]
	prefetchw [r3, 32]	;Prefetch the next write location

	SHIFT_1	(r7, r6, 24)
	or	r7, r7, r5
	SHIFT_2	(r5, r6, 8)

	SHIFT_1	(r9, r8, 24)
	or	r9, r9, r5
	SHIFT_2	(r5, r8, 8)

	st.ab	r7, [r3, 4]
	st.ab	r9, [r3, 4]
copy8bytes_1:

	;; Write back the remaining 16bits
	EXTRACT_1 (r6, r5, 16)
	sth.ab	r6, [r3, 2]
	;; Write back the remaining 8bits
	EXTRACT_2 (r5, r5, 16)
	stb.ab	r5, [r3, 1]

	and.f	lp_count, r2, 0x07 ;Last 8bytes
	lpnz	@copybytewise_1
	;; LOOP START
	ldb.ab	r6, [r1,1]
	stb.ab	r6, [r3,1]
copybytewise_1:
	j	[blink]

unalignedOffby2:
;;; CASE 2: The source is unaligned, off by 2
	ldh.ab	r5, [r1, 2]
	sub	r2, r2, 1

	;; Both src and dst are aligned
	;; Convert to words, unfold x2
	lsr.f	lp_count, r2, 3
#ifdef __BIG_ENDIAN__
	asl.nz	r5, r5, 16
#endif
	lpnz	@copy8bytes_2
	;; LOOP START
	ld.ab	r6, [r1, 4]
	prefetch [r1, 28]	;Prefetch the next read location
	ld.ab	r8, [r1,4]
	prefetchw [r3, 32]	;Prefetch the next write location

	SHIFT_1	(r7, r6, 16)
	or	r7, r7, r5
	SHIFT_2	(r5, r6, 16)

	SHIFT_1	(r9, r8, 16)
	or	r9, r9, r5
	SHIFT_2	(r5, r8, 16)

	st.ab	r7, [r3, 4]
	st.ab	r9, [r3, 4]
copy8bytes_2:

#ifdef __BIG_ENDIAN__
	lsr.nz	r5, r5, 16
#endif
	sth.ab	r5, [r3, 2]

	and.f	lp_count, r2, 0x07 ;Last 8bytes
	lpnz	@copybytewise_2
	;; LOOP START
	ldb.ab	r6, [r1,1]
	stb.ab	r6, [r3,1]
copybytewise_2:
	j	[blink]

unalignedOffby3:
;;; CASE 3: The source is unaligned, off by 3
;;; Hence, I need to read 1byte for achieve the 32bit alignment

	;; Both src and dst are aligned
	;; Convert to words, unfold x2
	lsr.f	lp_count, r2, 3
#ifdef __BIG_ENDIAN__
	asl.ne	r5, r5, 24
#endif
	lpnz	@copy8bytes_3
	;; LOOP START
	ld.ab	r6, [r1, 4]
	prefetch [r1, 28]	;Prefetch the next read location
	ld.ab	r8, [r1,4]
	prefetch [r3, 32]	;Prefetch the next write location

	SHIFT_1	(r7, r6, 8)
	or	r7, r7, r5
	SHIFT_2	(r5, r6, 24)

	SHIFT_1	(r9, r8, 8)
	or	r9, r9, r5
	SHIFT_2	(r5, r8, 24)

	st.ab	r7, [r3, 4]
	st.ab	r9, [r3, 4]
copy8bytes_3:

#ifdef __BIG_ENDIAN__
	lsr.nz	r5, r5, 24
#endif
	stb.ab	r5, [r3, 1]

	and.f	lp_count, r2, 0x07 ;Last 8bytes
	lpnz	@copybytewise_3
	;; LOOP START
	ldb.ab	r6, [r1,1]
	stb.ab	r6, [r3,1]
copybytewise_3:
	j	[blink]

END(memcpy)
OpenPOWER on IntegriCloud