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
|
;===========================================================================
; Copyright (c) 1990-1999 Info-ZIP. All rights reserved.
;
; See the accompanying file LICENSE, version 1999-Oct-05 or later
; (the contents of which are also included in zip.h) for terms of use.
; If, for some reason, both of these files are missing, the Info-ZIP license
; also may be found at: ftp://ftp.cdrom.com/pub/infozip/license.html
;===========================================================================
; match.s for ARM by Sergio Monesi.
r0 RN 0
r1 RN 1
r2 RN 2
r3 RN 3
r4 RN 4
r5 RN 5
r6 RN 6
r7 RN 7
r8 RN 8
r9 RN 9
sl RN 10
fp RN 11
ip RN 12
sp RN 13
lr RN 14
pc RN 15
MAX_DIST EQU 32506
WMASK EQU 32767
MAX_MATCH EQU 258
AREA |C$$code|, CODE, READONLY
; r1 = chain_lenght
; r2 = scan
; r3 = match
; r4 = len (tmp)
; r5 = best_len
; r6 = limit
; r7 = strend
; r8 = scan_end1
; r9 = scan_end
; lr = window
; fp = prev
|__max_chain_length|
IMPORT max_chain_length
DCD max_chain_length
|__window|
IMPORT window
DCD window
|__prev|
IMPORT prev
DCD prev
|__prev_length|
IMPORT prev_length
DCD prev_length
|__strstart|
IMPORT strstart
DCD strstart
|__good_match|
IMPORT good_match
DCD good_match
|__nice_match|
IMPORT nice_match
DCD nice_match
|__match_start|
IMPORT match_start
DCD match_start
DCB "longest_match"
DCB &00,&00,&00
DCD &ff000010
EXPORT longest_match
longest_match
STMFD sp!, {r4-r9,fp,lr}
LDR fp, [pc, #|__prev|-.-8]
LDR r1, [pc, #|__max_chain_length|-.-8]
LDR r1, [r1]
LDR lr, [pc, #|__window|-.-8]
LDR ip, [pc, #|__strstart|-.-8]
LDR ip, [ip]
ADD r2, lr, ip
LDR r5, [pc, #|__prev_length|-.-8]
LDR r5, [r5]
SUBS ip, ip, #MAX_DIST-250 ; if r6 > MAX_DIST
SUBCSS r6, ip, #250 ; r6 = r6 - MAXDIST
MOVLS r6, #0 ; else r6 = 0
ADD r7, r2, #MAX_MATCH-256
ADD r7, r7, #256 ; r7 = r2 + MAX_MATCH (=258);
SUB ip, r5, #1
LDRB r8, [r2, ip]
LDRB r9, [r2, r5]
LDR ip, [pc, #|__good_match|-.-8]
LDR ip, [ip]
CMP r5, ip
MOVCS r1, r1, LSR #2
cycle
ADD r3, lr, r0
LDRB ip, [r3, r5]
CMP ip, r9
BNE cycle_end
SUB ip, r5, #1
LDRB ip, [r3, ip]
CMP ip, r8
BNE cycle_end
LDRB ip, [r2]
LDRB r4, [r3]
CMP ip, r4
BNE cycle_end
LDRB ip, [r3, #1]
LDRB r4, [r2, #1]
CMP ip, r4
BNE cycle_end
ADD r2, r2, #2
ADD r3, r3, #2
inn_cycle
LDRB ip, [r2, #1]!
LDRB r4, [r3, #1]!
CMP ip, r4
BNE exit_inn_cycle
LDRB ip, [r2, #1]!
LDRB r4, [r3, #1]!
CMP ip, r4
BNE exit_inn_cycle
LDRB ip, [r2, #1]!
LDRB r4, [r3, #1]!
CMP ip, r4
BNE exit_inn_cycle
LDRB ip, [r2, #1]!
LDRB r4, [r3, #1]!
CMP ip, r4
BNE exit_inn_cycle
LDRB ip, [r2, #1]!
LDRB r4, [r3, #1]!
CMP ip, r4
BNE exit_inn_cycle
LDRB ip, [r2, #1]!
LDRB r4, [r3, #1]!
CMP ip, r4
BNE exit_inn_cycle
LDRB ip, [r2, #1]!
LDRB r4, [r3, #1]!
CMP ip, r4
BNE exit_inn_cycle
LDRB ip, [r2, #1]!
LDRB r4, [r3, #1]!
CMP ip, r4
BNE exit_inn_cycle
CMP r2, r7
BCC inn_cycle
exit_inn_cycle
SUB r4, r2, r7 ; len = MAX_MATCH - (int)(strend - scan);
ADD r4, r4, #MAX_MATCH-256
ADD r4, r4, #256
SUB r2, r2, r4 ; scan = strend - MAX_MATCH
CMP r4, r5 ; if (len > best_len) {
BLE cycle_end
LDR ip, [pc, #|__match_start|-.-8] ; match_start = cur_match;
STR r0, [ip]
MOV r5, r4 ; best_len = len;
LDR ip, [pc, #|__nice_match|-.-8] ; if (len >= nice_match)
LDR ip, [ip]
CMP r4, ip
BGE exit_match ; break;
SUB ip, r5, #1 ; scan_end1 = scan[best_len-1];
LDRB r8, [r2, ip]
LDRB r9, [r2, r5] ; scan_end = scan[best_len];
cycle_end
MOV ip, r0, LSL #17 ; cur_match & WMASK
MOV ip, ip, LSR #17
LDR r0, [fp, ip, ASL #1] ; cur_match = prev[cur_match & WMASK]
MOV r0, r0, ASL #16
MOV r0, r0, LSR #16
CMP r0, r6 ; cur_match > limit
BLS exit_match
SUBS r1, r1, #1 ; --chain_length
BNE cycle ; chain_length != 0
exit_match
MOV r0, r5
LDMFD sp!, {r4-r9,fp,pc}^
END
|
