2 ; Copyright (c) 2010 The VP8 project authors. All Rights Reserved.
4 ; Use of this source code is governed by a BSD-style license and patent
5 ; grant that can be found in the LICENSE file in the root of the source
6 ; tree. All contributing project authors may be found in the AUTHORS
7 ; file in the root of the source tree.
11 EXPORT |vp8cx_pack_tokens_into_partitions_armv7|
13 INCLUDE vpx_vp8_enc_asm_offsets.asm
19 AREA |.text|, CODE, READONLY
22 ; r1 unsigned char *cx_data
25 ; s0 vp8_coef_encodings
27 ; s2 const vp8_tree_index *,
29 |vp8cx_pack_tokens_into_partitions_armv7| PROC
33 ; Compute address of cpi->common.mb_rows
34 ldr r4, _VP8_COMP_common_
35 ldr r6, _VP8_COMMON_MBrows_
38 ldr r5, [r4, r6] ; load up mb_rows
40 str r5, [sp, #36] ; save mb_rows
41 str r1, [sp, #24] ; save cx_data
42 str r2, [sp, #20] ; save num_part
43 str r3, [sp, #8] ; save *size
45 ; *size = 3*(num_part -1 );
46 sub r2, r2, #1 ; num_part - 1
47 add r2, r2, r2, lsl #1 ; 3*(num_part - 1)
50 add r2, r2, r1 ; cx_data + *size
51 str r2, [sp, #40] ; ptr
53 ldr r4, _VP8_COMP_tplist_
55 ldr r7, [r4, #0] ; dereference cpi->tp_list
56 str r7, [sp, #32] ; store start of cpi->tp_list
58 ldr r11, _VP8_COMP_bc2_ ; load up vp8_writer out of cpi
62 str r11, [sp, #28] ; i
65 ldr r10, [sp, #40] ; ptr
66 ldr r5, [sp, #36] ; move mb_rows to the counting section
69 ; Reset all of the VP8 Writer data for each partition that
72 mov r2, #0 ; vp8_writer_lowvalue
73 mov r5, #255 ; vp8_writer_range
74 mvn r3, #23 ; vp8_writer_count
76 str r2, [r0, #vp8_writer_value]
77 str r2, [r0, #vp8_writer_pos]
78 str r10, [r0, #vp8_writer_buffer]
82 ldr r1, [r7, #tokenlist_start]
83 ldr r9, [r7, #tokenlist_stop]
84 str r9, [sp, #0] ; save stop for later comparison
85 str r7, [sp, #16] ; tokenlist address for next time
89 ; actual work gets done here!
92 ldr r6, [r1, #tokenextra_token] ; t
93 ldr r4, [sp, #80] ; vp8_coef_encodings
95 add r4, r4, r6, lsl #3 ; a = vp8_coef_encodings + t
96 ldr r9, [r1, #tokenextra_context_tree] ; pp
98 ldr r7, [r1, #tokenextra_skip_eob_node]
100 ldr r6, [r4, #vp8_token_value] ; v
101 ldr r8, [r4, #vp8_token_len] ; n
103 ; vp8 specific skip_eob_node
106 subne r8, r8, #1 ; --n
108 ; reverse the stream of bits to be packed. Normally
109 ; the most significant bit is peeled off and compared
110 ; in the form of (v >> --n) & 1. ARM architecture has
111 ; the ability to set a flag based on the value of the
112 ; bit shifted off the bottom of the register. To make
113 ; that happen the bitstream is reversed.
115 rsb r4, r8, #32 ; 32-n
116 ldr r10, [sp, #88] ; vp8_coef_tree
118 ; v is kept in r12 during the token pack loop
119 lsr r12, r12, r4 ; v >>= 32 - n
123 ldrb r4, [r9, lr, asr #1] ; pp [i>>1]
124 sub r7, r5, #1 ; range-1
126 ; Decisions are made based on the bit value shifted
127 ; off of v, so set a flag here based on this.
128 ; This value is refered to as "bb"
129 lsrs r12, r12, #1 ; bb = v >> n
130 mul r4, r4, r7 ; ((range-1) * pp[i>>1]))
132 ; bb can only be 0 or 1. So only execute this statement
133 ; if bb == 1, otherwise it will act like i + 0
134 addcs lr, lr, #1 ; i + bb
137 ldrsb lr, [r10, lr] ; i = vp8_coef_tree[i+bb]
138 add r4, r7, r4, lsr #8 ; 1 + (((range-1) * pp[i>>1]) >> 8)
140 addcs r2, r2, r4 ; if (bb) lowvalue += split
141 subcs r4, r5, r4 ; if (bb) range = range-split
143 ; Counting the leading zeros is used to normalize range.
145 sub r6, r6, #24 ; shift
147 ; Flag is set on the sum of count. This flag is used later
148 ; to determine if count >= 0
149 adds r3, r3, r6 ; count += shift
150 lsl r5, r4, r6 ; range <<= shift
151 bmi token_count_lt_zero ; if(count >= 0)
153 sub r6, r6, r3 ; offset = shift - count
154 sub r4, r6, #1 ; offset-1
155 lsls r4, r2, r4 ; if((lowvalue<<(offset-1)) & 0x80000000 )
156 bpl token_high_bit_not_set
158 ldr r4, [r0, #vp8_writer_pos] ; x
159 sub r4, r4, #1 ; x = w->pos-1
160 b token_zero_while_start
161 token_zero_while_loop
163 strb r10, [r7, r4] ; w->buffer[x] =(unsigned char)0
165 token_zero_while_start
167 ldrge r7, [r0, #vp8_writer_buffer]
170 beq token_zero_while_loop
172 ldr r7, [r0, #vp8_writer_buffer]
173 ldrb r10, [r7, r4] ; w->buffer[x]
175 strb r10, [r7, r4] ; w->buffer[x] + 1
176 token_high_bit_not_set
177 rsb r4, r6, #24 ; 24-offset
178 ldr r10, [r0, #vp8_writer_buffer]
179 lsr r7, r2, r4 ; lowvalue >> (24-offset)
180 ldr r4, [r0, #vp8_writer_pos] ; w->pos
181 lsl r2, r2, r6 ; lowvalue <<= offset
182 mov r6, r3 ; shift = count
183 add r11, r4, #1 ; w->pos++
184 bic r2, r2, #0xff000000 ; lowvalue &= 0xffffff
185 str r11, [r0, #vp8_writer_pos]
186 sub r3, r3, #8 ; count -= 8
187 strb r7, [r10, r4] ; w->buffer[w->pos++]
189 ; r10 is used earlier in the loop, but r10 is used as
190 ; temp variable here. So after r10 is used, reload
191 ; vp8_coef_tree_dcd into r10
192 ldr r10, [sp, #88] ; vp8_coef_tree
195 lsl r2, r2, r6 ; lowvalue <<= shift
197 subs r8, r8, #1 ; --n
200 ldr r6, [r1, #tokenextra_token] ; t
201 ldr r7, [sp, #84] ; vp8_extra_bits
202 ; Add t * sizeof (vp8_extra_bit_struct) to get the desired
203 ; element. Here vp8_extra_bit_struct == 20
204 add r6, r6, r6, lsl #2 ; b = vp8_extra_bits + t
205 add r12, r7, r6, lsl #2 ; b = vp8_extra_bits + t
207 ldr r4, [r12, #vp8_extra_bit_struct_base_val]
212 ldr r8, [r12, #vp8_extra_bit_struct_len] ; L
213 ldr lr, [r1, #tokenextra_extra] ; e = p->Extra
217 ldr r9, [r12, #vp8_extra_bit_struct_prob]
218 asr r7, lr, #1 ; v=e>>1
220 ldr r10, [r12, #vp8_extra_bit_struct_tree]
221 str r10, [sp, #4] ; b->tree
223 rbit r12, r7 ; reverse v
230 ldrb r4, [r9, lr, asr #1] ; pp[i>>1]
231 sub r7, r5, #1 ; range-1
232 lsrs r12, r12, #1 ; v >> n
233 mul r4, r4, r7 ; (range-1) * pp[i>>1]
234 addcs lr, lr, #1 ; i + bb
237 ldrsb lr, [r10, lr] ; i = b->tree[i+bb]
238 add r4, r7, r4, lsr #8 ; split = 1 + (((range-1) * pp[i>>1]) >> 8)
240 addcs r2, r2, r4 ; if (bb) lowvalue += split
241 subcs r4, r5, r4 ; if (bb) range = range-split
246 adds r3, r3, r6 ; count += shift
247 lsl r5, r4, r6 ; range <<= shift
248 bmi extra_count_lt_zero ; if(count >= 0)
250 sub r6, r6, r3 ; offset= shift - count
251 sub r4, r6, #1 ; offset-1
252 lsls r4, r2, r4 ; if((lowvalue<<(offset-1)) & 0x80000000 )
253 bpl extra_high_bit_not_set
255 ldr r4, [r0, #vp8_writer_pos] ; x
256 sub r4, r4, #1 ; x = w->pos - 1
257 b extra_zero_while_start
258 extra_zero_while_loop
260 strb r10, [r7, r4] ; w->buffer[x] =(unsigned char)0
262 extra_zero_while_start
264 ldrge r7, [r0, #vp8_writer_buffer]
267 beq extra_zero_while_loop
269 ldr r7, [r0, #vp8_writer_buffer]
273 extra_high_bit_not_set
274 rsb r4, r6, #24 ; 24-offset
275 ldr r10, [r0, #vp8_writer_buffer]
276 lsr r7, r2, r4 ; lowvalue >> (24-offset)
277 ldr r4, [r0, #vp8_writer_pos]
278 lsl r2, r2, r6 ; lowvalue <<= offset
279 mov r6, r3 ; shift = count
280 add r11, r4, #1 ; w->pos++
281 bic r2, r2, #0xff000000 ; lowvalue &= 0xffffff
282 str r11, [r0, #vp8_writer_pos]
283 sub r3, r3, #8 ; count -= 8
284 strb r7, [r10, r4] ; w->buffer[w->pos++]=(lowvalue >> (24-offset))
285 ldr r10, [sp, #4] ; b->tree
289 subs r8, r8, #1 ; --n
290 bne extra_bits_loop ; while (n)
293 ldr lr, [r1, #4] ; e = p->Extra
294 add r4, r5, #1 ; range + 1
296 lsr r4, r4, #1 ; split = (range + 1) >> 1
297 addne r2, r2, r4 ; lowvalue += split
298 subne r4, r5, r4 ; range = range-split
299 tst r2, #0x80000000 ; lowvalue & 0x80000000
300 lsl r5, r4, #1 ; range <<= 1
301 beq end_high_bit_not_set
303 ldr r4, [r0, #vp8_writer_pos]
306 b end_zero_while_start
312 ldrge r6, [r0, #vp8_writer_buffer]
315 beq end_zero_while_loop
317 ldr r6, [r0, #vp8_writer_buffer]
322 adds r3, r3, #1 ; ++count
323 lsl r2, r2, #1 ; lowvalue <<= 1
326 ldr r4, [r0, #vp8_writer_pos]
328 ldr r7, [r0, #vp8_writer_buffer]
329 lsr r6, r2, #24 ; lowvalue >> 24
330 add r12, r4, #1 ; w->pos++
331 bic r2, r2, #0xff000000 ; lowvalue &= 0xffffff
336 add r1, r1, #TOKENEXTRA_SZ ; ++p
338 ldr r4, [sp, #0] ; stop
339 cmp r1, r4 ; while( p < stop)
342 ldr r10, [sp, #20] ; num_parts
343 mov r1, #TOKENLIST_SZ
346 ldr r6, [sp, #12] ; mb_rows
347 ldr r7, [sp, #16] ; tokenlist address
349 add r7, r7, r1 ; next element in the array
356 sub r7, r5, #1 ; range-1
358 mov r4, r7, lsl #7 ; ((range-1) * 128)
361 add r4, r7, r4, lsr #8 ; 1 + (((range-1) * 128) >> 8)
363 ; Counting the leading zeros is used to normalize range.
365 sub r6, r6, #24 ; shift
367 ; Flag is set on the sum of count. This flag is used later
368 ; to determine if count >= 0
369 adds r3, r3, r6 ; count += shift
370 lsl r5, r4, r6 ; range <<= shift
371 bmi token_count_lt_zero_se ; if(count >= 0)
373 sub r6, r6, r3 ; offset = shift - count
374 sub r4, r6, #1 ; offset-1
375 lsls r4, r2, r4 ; if((lowvalue<<(offset-1)) & 0x80000000 )
376 bpl token_high_bit_not_set_se
378 ldr r4, [r0, #vp8_writer_pos] ; x
379 sub r4, r4, #1 ; x = w->pos-1
380 b token_zero_while_start_se
381 token_zero_while_loop_se
383 strb r10, [r7, r4] ; w->buffer[x] =(unsigned char)0
385 token_zero_while_start_se
387 ldrge r7, [r0, #vp8_writer_buffer]
390 beq token_zero_while_loop_se
392 ldr r7, [r0, #vp8_writer_buffer]
393 ldrb r10, [r7, r4] ; w->buffer[x]
395 strb r10, [r7, r4] ; w->buffer[x] + 1
396 token_high_bit_not_set_se
397 rsb r4, r6, #24 ; 24-offset
398 ldr r10, [r0, #vp8_writer_buffer]
399 lsr r7, r2, r4 ; lowvalue >> (24-offset)
400 ldr r4, [r0, #vp8_writer_pos] ; w->pos
401 lsl r2, r2, r6 ; lowvalue <<= offset
402 mov r6, r3 ; shift = count
403 add r11, r4, #1 ; w->pos++
404 bic r2, r2, #0xff000000 ; lowvalue &= 0xffffff
405 str r11, [r0, #vp8_writer_pos]
406 sub r3, r3, #8 ; count -= 8
407 strb r7, [r10, r4] ; w->buffer[w->pos++]
409 token_count_lt_zero_se
410 lsl r2, r2, r6 ; lowvalue <<= shift
415 ldr r10, [sp, #8] ; *size
417 ldr r4, [r0, #vp8_writer_pos] ; w->pos
418 add r11, r11, r4 ; *size += w->pos
421 ldr r9, [sp, #20] ; num_parts
423 ldr r10, [sp, #28] ; i
424 cmp r10, r9 ; if(i<(num_part - 1))
425 bge skip_write_partition
427 ldr r12, [sp, #40] ; ptr
428 add r12, r12, r4 ; ptr += w->pos
431 ldr r9, [sp, #24] ; cx_data
438 add r9, r9, #3 ; cx_data += 3
443 ldr r11, [sp, #28] ; i
444 ldr r10, [sp, #20] ; num_parts
446 add r11, r11, #1 ; i++
449 ldr r7, [sp, #32] ; cpi->tp_list[i]
450 mov r1, #TOKENLIST_SZ
451 add r7, r7, r1 ; next element in cpi->tp_list
452 str r7, [sp, #32] ; cpi->tp_list[i+1]
465 DCD vp8_common_mb_rows