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
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
|
;
; Copyright (c) 2010 The VP8 project authors. All Rights Reserved.
;
; Use of this source code is governed by a BSD-style license
; that can be found in the LICENSE file in the root of the source
; tree. An additional intellectual property rights grant can be found
; in the file PATENTS. All contributing project authors may
; be found in the AUTHORS file in the root of the source tree.
;
EXPORT |vp8_decode_mb_tokens_v6|
AREA |.text|, CODE, READONLY ; name this block of code
INCLUDE vpx_asm_offsets.asm
l_qcoeff EQU 0
l_i EQU 4
l_type EQU 8
l_stop EQU 12
l_c EQU 16
l_l_ptr EQU 20
l_a_ptr EQU 24
l_bc EQU 28
l_coef_ptr EQU 32
l_stacksize EQU 64
;; constant offsets -- these should be created at build time
c_block2above_offset EQU 25
c_entropy_nodes EQU 11
c_dct_eob_token EQU 11
|vp8_decode_mb_tokens_v6| PROC
stmdb sp!, {r4 - r11, lr}
sub sp, sp, #l_stacksize
mov r7, r1 ; type
mov r9, r0 ; detoken
ldr r1, [r9, #detok_current_bc]
ldr r0, [r9, #detok_qcoeff_start_ptr]
mov r11, #0 ; i
mov r3, #16 ; stop
cmp r7, #1 ; type ?= 1
addeq r11, r11, #24 ; i = 24
addeq r3, r3, #8 ; stop = 24
addeq r0, r0, #3, 24 ; qcoefptr += 24*16
str r0, [sp, #l_qcoeff]
str r11, [sp, #l_i]
str r7, [sp, #l_type]
str r3, [sp, #l_stop]
str r1, [sp, #l_bc]
add lr, r9, r7, lsl #2 ; detoken + type*4
ldr r8, [r1, #bool_decoder_user_buffer]
ldr r10, [lr, #detok_coef_probs]
ldr r5, [r1, #bool_decoder_count]
ldr r6, [r1, #bool_decoder_range]
ldr r4, [r1, #bool_decoder_value]
str r10, [sp, #l_coef_ptr]
BLOCK_LOOP
ldr r3, [r9, #detok_ptr_block2leftabove]
ldr r1, [r9, #detok_L]
ldr r2, [r9, #detok_A]
ldrb r12, [r3, r11]! ; block2left[i]
ldrb r3, [r3, #c_block2above_offset]; block2above[i]
cmp r7, #0 ; c = !type
moveq r7, #1
movne r7, #0
ldrb r0, [r1, r12]! ; *(L += block2left[i])
ldrb r3, [r2, r3]! ; *(A += block2above[i])
mov lr, #c_entropy_nodes ; ENTROPY_NODES = 11
; VP8_COMBINEENTROPYCONTETEXTS(t, *a, *l) => t = ((*a) != 0) + ((*l) !=0)
cmp r0, #0 ; *l ?= 0
movne r0, #1
cmp r3, #0 ; *a ?= 0
addne r0, r0, #1 ; t
str r1, [sp, #l_l_ptr] ; save &l
str r2, [sp, #l_a_ptr] ; save &a
smlabb r0, r0, lr, r10 ; Prob = coef_probs + (t * ENTROPY_NODES)
mov r1, #0 ; t = 0
str r7, [sp, #l_c]
;align 4
COEFF_LOOP
ldr r3, [r9, #detok_ptr_coef_bands_x]
ldr lr, [r9, #detok_coef_tree_ptr]
;STALL
ldrb r3, [r3, r7] ; coef_bands_x[c]
;STALL
;STALL
add r0, r0, r3 ; Prob += coef_bands_x[c]
get_token_loop
ldrb r2, [r0, +r1, asr #1] ; Prob[t >> 1]
mov r3, r6, lsl #8 ; range << 8
sub r3, r3, #256 ; (range << 8) - (1 << 8)
mov r10, #1 ; 1
smlawb r2, r3, r2, r10 ; split = 1 + (((range-1) * probability) >> 8)
ldrb r12, [r8] ; load cx data byte in stall slot : r8 = bufptr
;++
subs r3, r4, r2, lsl #24 ; value-(split<<24): used later to calculate shift for NORMALIZE
addhs r1, r1, #1 ; t += 1
movhs r4, r3 ; value -= bigsplit (split << 24)
subhs r2, r6, r2 ; range -= split
; movlo r6, r2 ; range = split
ldrsb r1, [lr, r1] ; t = onyx_coef_tree_ptr[t]
; NORMALIZE
clz r3, r2 ; vp8dx_bitreader_norm[range] + 24
sub r3, r3, #24 ; vp8dx_bitreader_norm[range]
subs r5, r5, r3 ; count -= shift
mov r6, r2, lsl r3 ; range <<= shift
mov r4, r4, lsl r3 ; value <<= shift
; if count <= 0, += BR_COUNT; value |= *bufptr++ << (BR_COUNT-count); BR_COUNT = 8, but need to upshift values by +16
addle r5, r5, #8 ; count += 8
rsble r3, r5, #24 ; 24 - count
addle r8, r8, #1 ; bufptr++
orrle r4, r4, r12, lsl r3 ; value |= *bufptr << shift + 16
cmp r1, #0 ; t ?= 0
bgt get_token_loop ; while (t > 0)
cmn r1, #c_dct_eob_token ; if(t == -DCT_EOB_TOKEN)
beq END_OF_BLOCK ; break
rsb lr, r1, #0 ; v = -t;
cmp lr, #4 ; if(v > FOUR_TOKEN)
ble SKIP_EXTRABITS
ldr r3, [r9, #detok_teb_base_ptr]
mov r11, #1 ; 1 in split = 1 + ... nope, v+= 1 << bits_count
add r7, r3, lr, lsl #4 ; detok_teb_base_ptr + (v << 4)
ldrsh lr, [r7, #tokenextrabits_min_val] ; v = teb_ptr->min_val
ldrsh r0, [r7, #tokenextrabits_length] ; bits_count = teb_ptr->Length
extrabits_loop
add r3, r0, r7 ; &teb_ptr->Probs[bits_count]
ldrb r2, [r3, #4] ; probability. why +4?
mov r3, r6, lsl #8 ; range << 8
sub r3, r3, #256 ; range << 8 + 1 << 8
smlawb r2, r3, r2, r11 ; split = 1 + (((range-1) * probability) >> 8)
ldrb r12, [r8] ; *bufptr
;++
subs r10, r4, r2, lsl #24 ; value - (split<<24)
movhs r4, r10 ; value = value - (split << 24)
subhs r2, r6, r2 ; range = range - split
addhs lr, lr, r11, lsl r0 ; v += ((UINT16)1<<bits_count)
; NORMALIZE
clz r3, r2 ; shift - leading zeros in split
sub r3, r3, #24 ; don't count first 3 bytes
subs r5, r5, r3 ; count -= shift
mov r6, r2, lsl r3 ; range = range << shift
mov r4, r4, lsl r3 ; value <<= shift
addle r5, r5, #8 ; count += BR_COUNT
addle r8, r8, #1 ; bufptr++
rsble r3, r5, #24 ; BR_COUNT - count
orrle r4, r4, r12, lsl r3 ; value |= *bufptr << (BR_COUNT - count)
subs r0, r0, #1 ; bits_count --
bpl extrabits_loop
SKIP_EXTRABITS
ldr r11, [sp, #l_qcoeff]
ldr r0, [sp, #l_coef_ptr] ; Prob = coef_probs
cmp r1, #0 ; check for nonzero token - if (t)
beq SKIP_EOB_CHECK ; if t is zero, we will skip the eob table chec
add r3, r6, #1 ; range + 1
mov r2, r3, lsr #1 ; split = (range + 1) >> 1
subs r3, r4, r2, lsl #24 ; value - (split<<24)
movhs r4, r3 ; value -= (split << 24)
subhs r2, r6, r2 ; range -= split
mvnhs r3, lr ; -v
addhs lr, r3, #1 ; v = (v ^ -1) + 1
; NORMALIZE
clz r3, r2 ; leading 0s in split
sub r3, r3, #24 ; shift
subs r5, r5, r3 ; count -= shift
mov r6, r2, lsl r3 ; range <<= shift
mov r4, r4, lsl r3 ; value <<= shift
ldrleb r2, [r8], #1 ; *(bufptr++)
addle r5, r5, #8 ; count += 8
rsble r3, r5, #24 ; BR_COUNT - count
orrle r4, r4, r2, lsl r3 ; value |= *bufptr << (BR_COUNT - count)
add r0, r0, #11 ; Prob += ENTROPY_NODES (11)
cmn r1, #1 ; t < -ONE_TOKEN
addlt r0, r0, #11 ; Prob += ENTROPY_NODES (11)
mvn r1, #1 ; t = -1 ???? C is -2
SKIP_EOB_CHECK
ldr r7, [sp, #l_c] ; c
ldr r3, [r9, #detok_scan]
add r1, r1, #2 ; t+= 2
cmp r7, #15 ; c should will be one higher
ldr r3, [r3, +r7, lsl #2] ; scan[c] this needs pre-inc c value
add r7, r7, #1 ; c++
add r3, r11, r3, lsl #1 ; qcoeff + scan[c]
str r7, [sp, #l_c] ; store c
strh lr, [r3] ; qcoef_ptr[scan[c]] = v
blt COEFF_LOOP
sub r7, r7, #1 ; if(t != -DCT_EOB_TOKEN) --c
END_OF_BLOCK
ldr r3, [sp, #l_type] ; type
ldr r10, [sp, #l_coef_ptr] ; coef_ptr
ldr r0, [sp, #l_qcoeff] ; qcoeff
ldr r11, [sp, #l_i] ; i
ldr r12, [sp, #l_stop] ; stop
cmp r3, #0 ; type ?= 0
moveq r1, #1
movne r1, #0
add r3, r11, r9 ; detok + i
cmp r7, r1 ; c ?= !type
strb r7, [r3, #detok_eob] ; eob[i] = c
ldr r7, [sp, #l_l_ptr] ; l
ldr r2, [sp, #l_a_ptr] ; a
movne r3, #1 ; t
moveq r3, #0
add r0, r0, #32 ; qcoeff += 32 (16 * 2?)
add r11, r11, #1 ; i++
strb r3, [r7] ; *l = t
strb r3, [r2] ; *a = t
str r0, [sp, #l_qcoeff] ; qcoeff
str r11, [sp, #l_i] ; i
cmp r11, r12 ; i < stop
ldr r7, [sp, #l_type] ; type
blt BLOCK_LOOP
cmp r11, #25 ; i ?= 25
bne ln2_decode_mb_to
ldr r12, [r9, #detok_qcoeff_start_ptr]
ldr r10, [r9, #detok_coef_probs]
mov r7, #0 ; type/i = 0
mov r3, #16 ; stop = 16
str r12, [sp, #l_qcoeff] ; qcoeff_ptr = qcoeff_start_ptr
str r7, [sp, #l_i]
str r7, [sp, #l_type]
str r3, [sp, #l_stop]
str r10, [sp, #l_coef_ptr] ; coef_probs = coef_probs[type=0]
b BLOCK_LOOP
ln2_decode_mb_to
cmp r11, #16 ; i ?= 16
bne ln1_decode_mb_to
mov r10, #detok_coef_probs
add r10, r10, #2*4 ; coef_probs[type]
ldr r10, [r9, r10] ; detok + detok_coef_probs[type]
mov r7, #2 ; type = 2
mov r3, #24 ; stop = 24
str r7, [sp, #l_type]
str r3, [sp, #l_stop]
str r10, [sp, #l_coef_ptr] ; coef_probs = coef_probs[type]
b BLOCK_LOOP
ln1_decode_mb_to
ldr r2, [sp, #l_bc]
mov r0, #0
nop
str r8, [r2, #bool_decoder_user_buffer]
str r5, [r2, #bool_decoder_count]
str r4, [r2, #bool_decoder_value]
str r6, [r2, #bool_decoder_range]
add sp, sp, #l_stacksize
ldmia sp!, {r4 - r11, pc}
ENDP ; |vp8_decode_mb_tokens_v6|
END
|
