; ; Copyright (c) 2010 The WebM 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<> 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