ref: 9fdfb8e92823abadc54d825d0603a7e9fd344520
dir: /vp8/encoder/arm/armv6/walsh_v6.asm/
;
; 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_short_walsh4x4_armv6|
ARM
REQUIRE8
PRESERVE8
AREA |.text|, CODE, READONLY ; name this block of code
;short vp8_short_walsh4x4_armv6(short *input, short *output, int pitch)
|vp8_short_walsh4x4_armv6| PROC
stmdb sp!, {r4 - r11, lr}
mov r12, r2 ; ugh. not clean
ldr r2, [r0] ; [1 | 0]
ldr r3, [r0, #4] ; [3 | 2]
ldr r4, [r0, r12]! ; [5 | 4]
ldr r5, [r0, #4] ; [7 | 6]
ldr r6, [r0, r12]! ; [9 | 8]
ldr r7, [r0, #4] ; [11 | 10]
ldr r8, [r0, r12]! ; [13 | 12]
ldr r9, [r0, #4] ; [15 | 14]
qsubaddx r10, r2, r3 ; [c1|a1] [1-2 | 0+3]
qaddsubx r11, r2, r3 ; [b1|d1] [1+2 | 0-3]
qsubaddx r12, r4, r5 ; [c1|a1] [5-6 | 4+7]
qaddsubx lr, r4, r5 ; [b1|d1] [5+6 | 4-7]
qaddsubx r2, r10, r11 ; [1 | 2] [c1+d1 | a1-b1]
qaddsubx r3, r11, r10 ; [0 | 3] [b1+a1 | d1-c1]
qaddsubx r4, r12, lr ; [5 | 6] [c1+d1 | a1-b1]
qaddsubx r5, lr, r12 ; [4 | 7] [b1+a1 | d1-c1]
qsubaddx r10, r6, r7 ; [c1|a1] [9-10 | 8+11]
qaddsubx r11, r6, r7 ; [b1|d1] [9+10 | 8-11]
qsubaddx r12, r8, r9 ; [c1|a1] [13-14 | 12+15]
qaddsubx lr, r8, r9 ; [b1|d1] [13+14 | 12-15]
qaddsubx r6, r10, r11 ; [9 |10] [c1+d1 | a1-b1]
qaddsubx r7, r11, r10 ; [8 |11] [b1+a1 | d1-c1]
qaddsubx r8, r12, lr ; [13|14] [c1+d1 | a1-b1]
qaddsubx r9, lr, r12 ; [12|15] [b1+a1 | d1-c1]
; first transform complete
qadd16 r10, r3, r9 ; a1 [0+12 | 3+15]
qadd16 r11, r5, r7 ; b1 [4+8 | 7+11]
qsub16 r12, r5, r7 ; c1 [4-8 | 7-11]
qsub16 lr, r3, r9 ; d1 [0-12 | 3-15]
qadd16 r3, r10, r11 ; a2 [a1+b1] [0 | 3]
qadd16 r5, r12, lr ; b2 [c1+d1] [4 | 7]
qsub16 r7, r10, r11 ; c2 [a1-b1] [8 |11]
qsub16 r9, lr, r12 ; d2 [d1-c1] [12|15]
qadd16 r10, r2, r8 ; a1 [1+13 | 2+14]
qadd16 r11, r4, r6 ; b1 [5+9 | 6+10]
qsub16 r12, r4, r6 ; c1 [5-9 | 6-10]
qsub16 lr, r2, r8 ; d1 [1-13 | 2-14]
qadd16 r2, r10, r11 ; a2 [a1+b1] [1 | 2]
qadd16 r4, r12, lr ; b2 [c1+d1] [5 | 6]
qsub16 r6, r10, r11 ; c2 [a1-b1] [9 |10]
qsub16 r8, lr, r12 ; d2 [d1-c1] [13|14]
; [a-d]2 += ([a-d]2 > 0)
asrs r10, r3, #16
addpl r10, r10, #1 ; [~0]
asrs r11, r2, #16
addpl r11, r11, #1 ; [~1]
lsl r11, r11, #15 ; [1 | x]
pkhtb r10, r11, r10, asr #1; [1 | 0]
str r10, [r1], #4
lsls r11, r2, #16
addpl r11, r11, #0x10000 ; [~2]
lsls r12, r3, #16
addpl r12, r12, #0x10000 ; [~3]
asr r12, r12, #1 ; [3 | x]
pkhtb r11, r12, r11, asr #17; [3 | 2]
str r11, [r1], #4
asrs r2, r5, #16
addpl r2, r2, #1 ; [~4]
asrs r3, r4, #16
addpl r3, r3, #1 ; [~5]
lsl r3, r3, #15 ; [5 | x]
pkhtb r2, r3, r2, asr #1 ; [5 | 4]
str r2, [r1], #4
lsls r2, r4, #16
addpl r2, r2, #0x10000 ; [~6]
lsls r3, r5, #16
addpl r3, r3, #0x10000 ; [~7]
asr r3, r3, #1 ; [7 | x]
pkhtb r2, r3, r2, asr #17 ; [7 | 6]
str r2, [r1], #4
asrs r2, r7, #16
addpl r2, r2, #1 ; [~8]
asrs r3, r6, #16
addpl r3, r3, #1 ; [~9]
lsl r3, r3, #15 ; [9 | x]
pkhtb r2, r3, r2, asr #1 ; [9 | 8]
str r2, [r1], #4
lsls r2, r6, #16
addpl r2, r2, #0x10000 ; [~10]
lsls r3, r7, #16
addpl r3, r3, #0x10000 ; [~11]
asr r3, r3, #1 ; [11 | x]
pkhtb r2, r3, r2, asr #17 ; [11 | 10]
str r2, [r1], #4
asrs r2, r9, #16
addpl r2, r2, #1 ; [~12]
asrs r3, r8, #16
addpl r3, r3, #1 ; [~13]
lsl r3, r3, #15 ; [13 | x]
pkhtb r2, r3, r2, asr #1 ; [13 | 12]
str r2, [r1], #4
lsls r2, r8, #16
addpl r2, r2, #0x10000 ; [~14]
lsls r3, r9, #16
addpl r3, r3, #0x10000 ; [~15]
asr r3, r3, #1 ; [15 | x]
pkhtb r2, r3, r2, asr #17 ; [15 | 14]
str r2, [r1]
ldmia sp!, {r4 - r11, pc}
ENDP ; |vp8_short_walsh4x4_armv6|
END