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Diffstat (limited to 'vp8/encoder/arm/neon/boolhuff_armv7.asm')
-rw-r--r--vp8/encoder/arm/neon/boolhuff_armv7.asm292
1 files changed, 292 insertions, 0 deletions
diff --git a/vp8/encoder/arm/neon/boolhuff_armv7.asm b/vp8/encoder/arm/neon/boolhuff_armv7.asm
new file mode 100644
index 000000000..9a5f36661
--- /dev/null
+++ b/vp8/encoder/arm/neon/boolhuff_armv7.asm
@@ -0,0 +1,292 @@
+;
+; Copyright (c) 2010 The VP8 project authors. All Rights Reserved.
+;
+; Use of this source code is governed by a BSD-style license and patent
+; grant that can be found in the LICENSE file in the root of the source
+; tree. All contributing project authors may be found in the AUTHORS
+; file in the root of the source tree.
+;
+
+
+ EXPORT |vp8_start_encode|
+ EXPORT |vp8_encode_bool|
+ EXPORT |vp8_stop_encode|
+ EXPORT |vp8_encode_value|
+
+ INCLUDE vpx_vp8_enc_asm_offsets.asm
+
+ ARM
+ REQUIRE8
+ PRESERVE8
+
+ AREA |.text|, CODE, READONLY
+
+; r0 BOOL_CODER *br
+; r1 unsigned char *source
+
+|vp8_start_encode| PROC
+ mov r12, #0
+ mov r3, #255
+ mvn r2, #23
+ str r12, [r0, #vp8_writer_lowvalue]
+ str r3, [r0, #vp8_writer_range]
+ str r12, [r0, #vp8_writer_value]
+ str r2, [r0, #vp8_writer_count]
+ str r12, [r0, #vp8_writer_pos]
+ str r1, [r0, #vp8_writer_buffer]
+ bx lr
+ ENDP
+
+; r0 BOOL_CODER *br
+; r1 int bit
+; r2 int probability
+|vp8_encode_bool| PROC
+ push {r4-r9, lr}
+
+ mov r4, r2
+
+ ldr r2, [r0, #vp8_writer_lowvalue]
+ ldr r5, [r0, #vp8_writer_range]
+ ldr r3, [r0, #vp8_writer_count]
+
+ sub r7, r5, #1 ; range-1
+
+ cmp r1, #0
+ mul r4, r4, r7 ; ((range-1) * probability)
+
+ mov r7, #1
+ add r4, r7, r4, lsr #8 ; 1 + (((range-1) * probability) >> 8)
+
+ addne r2, r2, r4 ; if (bit) lowvalue += split
+ subne r4, r5, r4 ; if (bit) range = range-split
+
+ ; Counting the leading zeros is used to normalize range.
+ clz r6, r4
+ sub r6, r6, #24 ; shift
+
+ ; Flag is set on the sum of count. This flag is used later
+ ; to determine if count >= 0
+ adds r3, r3, r6 ; count += shift
+ lsl r5, r4, r6 ; range <<= shift
+ bmi token_count_lt_zero ; if(count >= 0)
+
+ sub r6, r6, r3 ; offset = shift - count
+ sub r4, r6, #1 ; offset-1
+ lsls r4, r2, r4 ; if((lowvalue<<(offset-1)) & 0x80000000 )
+ bpl token_high_bit_not_set
+
+ ldr r4, [r0, #vp8_writer_pos] ; x
+ sub r4, r4, #1 ; x = w->pos-1
+ b token_zero_while_start
+token_zero_while_loop
+ mov r9, #0
+ strb r9, [r7, r4] ; w->buffer[x] =(unsigned char)0
+ sub r4, r4, #1 ; x--
+token_zero_while_start
+ cmp r4, #0
+ ldrge r7, [r0, #vp8_writer_buffer]
+ ldrb r1, [r7, r4]
+ cmpge r1, #0xff
+ beq token_zero_while_loop
+
+ ldr r7, [r0, #vp8_writer_buffer]
+ ldrb r9, [r7, r4] ; w->buffer[x]
+ add r9, r9, #1
+ strb r9, [r7, r4] ; w->buffer[x] + 1
+token_high_bit_not_set
+ rsb r4, r6, #24 ; 24-offset
+ ldr r9, [r0, #vp8_writer_buffer]
+ lsr r7, r2, r4 ; lowvalue >> (24-offset)
+ ldr r4, [r0, #vp8_writer_pos] ; w->pos
+ lsl r2, r2, r6 ; lowvalue <<= offset
+ mov r6, r3 ; shift = count
+ add r1, r4, #1 ; w->pos++
+ bic r2, r2, #0xff000000 ; lowvalue &= 0xffffff
+ str r1, [r0, #vp8_writer_pos]
+ sub r3, r3, #8 ; count -= 8
+ strb r7, [r9, r4] ; w->buffer[w->pos++]
+
+token_count_lt_zero
+ lsl r2, r2, r6 ; lowvalue <<= shift
+
+ str r2, [r0, #vp8_writer_lowvalue]
+ str r5, [r0, #vp8_writer_range]
+ str r3, [r0, #vp8_writer_count]
+ pop {r4-r9, pc}
+ ENDP
+
+; r0 BOOL_CODER *br
+|vp8_stop_encode| PROC
+ push {r4-r10, lr}
+
+ ldr r2, [r0, #vp8_writer_lowvalue]
+ ldr r5, [r0, #vp8_writer_range]
+ ldr r3, [r0, #vp8_writer_count]
+
+ mov r10, #32
+
+stop_encode_loop
+ sub r7, r5, #1 ; range-1
+
+ mov r4, r7, lsl #7 ; ((range-1) * 128)
+
+ mov r7, #1
+ add r4, r7, r4, lsr #8 ; 1 + (((range-1) * 128) >> 8)
+
+ ; Counting the leading zeros is used to normalize range.
+ clz r6, r4
+ sub r6, r6, #24 ; shift
+
+ ; Flag is set on the sum of count. This flag is used later
+ ; to determine if count >= 0
+ adds r3, r3, r6 ; count += shift
+ lsl r5, r4, r6 ; range <<= shift
+ bmi token_count_lt_zero_se ; if(count >= 0)
+
+ sub r6, r6, r3 ; offset = shift - count
+ sub r4, r6, #1 ; offset-1
+ lsls r4, r2, r4 ; if((lowvalue<<(offset-1)) & 0x80000000 )
+ bpl token_high_bit_not_set_se
+
+ ldr r4, [r0, #vp8_writer_pos] ; x
+ sub r4, r4, #1 ; x = w->pos-1
+ b token_zero_while_start_se
+token_zero_while_loop_se
+ mov r9, #0
+ strb r9, [r7, r4] ; w->buffer[x] =(unsigned char)0
+ sub r4, r4, #1 ; x--
+token_zero_while_start_se
+ cmp r4, #0
+ ldrge r7, [r0, #vp8_writer_buffer]
+ ldrb r1, [r7, r4]
+ cmpge r1, #0xff
+ beq token_zero_while_loop_se
+
+ ldr r7, [r0, #vp8_writer_buffer]
+ ldrb r9, [r7, r4] ; w->buffer[x]
+ add r9, r9, #1
+ strb r9, [r7, r4] ; w->buffer[x] + 1
+token_high_bit_not_set_se
+ rsb r4, r6, #24 ; 24-offset
+ ldr r9, [r0, #vp8_writer_buffer]
+ lsr r7, r2, r4 ; lowvalue >> (24-offset)
+ ldr r4, [r0, #vp8_writer_pos] ; w->pos
+ lsl r2, r2, r6 ; lowvalue <<= offset
+ mov r6, r3 ; shift = count
+ add r1, r4, #1 ; w->pos++
+ bic r2, r2, #0xff000000 ; lowvalue &= 0xffffff
+ str r1, [r0, #vp8_writer_pos]
+ sub r3, r3, #8 ; count -= 8
+ strb r7, [r9, r4] ; w->buffer[w->pos++]
+
+token_count_lt_zero_se
+ lsl r2, r2, r6 ; lowvalue <<= shift
+
+ subs r10, r10, #1
+ bne stop_encode_loop
+
+ str r2, [r0, #vp8_writer_lowvalue]
+ str r5, [r0, #vp8_writer_range]
+ str r3, [r0, #vp8_writer_count]
+ pop {r4-r10, pc}
+
+ ENDP
+
+; r0 BOOL_CODER *br
+; r1 int data
+; r2 int bits
+|vp8_encode_value| PROC
+ push {r4-r11, lr}
+
+ mov r10, r2
+
+ ldr r2, [r0, #vp8_writer_lowvalue]
+ ldr r5, [r0, #vp8_writer_range]
+ ldr r3, [r0, #vp8_writer_count]
+
+ ; reverse the stream of bits to be packed. Normally
+ ; the most significant bit is peeled off and compared
+ ; in the form of (v >> --n) & 1. ARM architecture has
+ ; the ability to set a flag based on the value of the
+ ; bit shifted off the bottom of the register. To make
+ ; that happen the bitstream is reversed.
+ rbit r11, r1
+ rsb r4, r10, #32 ; 32-n
+
+ ; v is kept in r1 during the token pack loop
+ lsr r1, r11, r4 ; v >>= 32 - n
+
+encode_value_loop
+ sub r7, r5, #1 ; range-1
+
+ ; Decisions are made based on the bit value shifted
+ ; off of v, so set a flag here based on this.
+ ; This value is refered to as "bb"
+ lsrs r1, r1, #1 ; bit = v >> n
+ mov r4, r7, lsl #7 ; ((range-1) * 128)
+
+ mov r7, #1
+ add r4, r7, r4, lsr #8 ; 1 + (((range-1) * 128) >> 8)
+
+ addcs r2, r2, r4 ; if (bit) lowvalue += split
+ subcs r4, r5, r4 ; if (bit) range = range-split
+
+ ; Counting the leading zeros is used to normalize range.
+ clz r6, r4
+ sub r6, r6, #24 ; shift
+
+ ; Flag is set on the sum of count. This flag is used later
+ ; to determine if count >= 0
+ adds r3, r3, r6 ; count += shift
+ lsl r5, r4, r6 ; range <<= shift
+ bmi token_count_lt_zero_ev ; if(count >= 0)
+
+ sub r6, r6, r3 ; offset = shift - count
+ sub r4, r6, #1 ; offset-1
+ lsls r4, r2, r4 ; if((lowvalue<<(offset-1)) & 0x80000000 )
+ bpl token_high_bit_not_set_ev
+
+ ldr r4, [r0, #vp8_writer_pos] ; x
+ sub r4, r4, #1 ; x = w->pos-1
+ b token_zero_while_start_ev
+token_zero_while_loop_ev
+ mov r9, #0
+ strb r9, [r7, r4] ; w->buffer[x] =(unsigned char)0
+ sub r4, r4, #1 ; x--
+token_zero_while_start_ev
+ cmp r4, #0
+ ldrge r7, [r0, #vp8_writer_buffer]
+ ldrb r11, [r7, r4]
+ cmpge r11, #0xff
+ beq token_zero_while_loop_ev
+
+ ldr r7, [r0, #vp8_writer_buffer]
+ ldrb r9, [r7, r4] ; w->buffer[x]
+ add r9, r9, #1
+ strb r9, [r7, r4] ; w->buffer[x] + 1
+token_high_bit_not_set_ev
+ rsb r4, r6, #24 ; 24-offset
+ ldr r9, [r0, #vp8_writer_buffer]
+ lsr r7, r2, r4 ; lowvalue >> (24-offset)
+ ldr r4, [r0, #vp8_writer_pos] ; w->pos
+ lsl r2, r2, r6 ; lowvalue <<= offset
+ mov r6, r3 ; shift = count
+ add r11, r4, #1 ; w->pos++
+ bic r2, r2, #0xff000000 ; lowvalue &= 0xffffff
+ str r11, [r0, #vp8_writer_pos]
+ sub r3, r3, #8 ; count -= 8
+ strb r7, [r9, r4] ; w->buffer[w->pos++]
+
+token_count_lt_zero_ev
+ lsl r2, r2, r6 ; lowvalue <<= shift
+
+ subs r10, r10, #1
+ bne encode_value_loop
+
+ str r2, [r0, #vp8_writer_lowvalue]
+ str r5, [r0, #vp8_writer_range]
+ str r3, [r0, #vp8_writer_count]
+ pop {r4-r11, pc}
+ ENDP
+
+ END