ref: d4c97f949f9e4ffe3461feacc8adb639c2824d49
dir: /vp8/common/arm/neon/iwalsh_neon.asm/
; ; 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_short_inv_walsh4x4_neon| ARM REQUIRE8 PRESERVE8 AREA |.text|, CODE, READONLY ; name this block of code ;short vp8_short_inv_walsh4x4_neon(short *input, short *mb_dqcoeff) |vp8_short_inv_walsh4x4_neon| PROC ; read in all four lines of values: d0->d3 vld1.i16 {q0-q1}, [r0@128] ; first for loop vadd.s16 d4, d0, d3 ;a = [0] + [12] vadd.s16 d6, d1, d2 ;b = [4] + [8] vsub.s16 d5, d0, d3 ;d = [0] - [12] vsub.s16 d7, d1, d2 ;c = [4] - [8] vadd.s16 q0, q2, q3 ; a+b d+c vsub.s16 q1, q2, q3 ; a-b d-c vtrn.32 d0, d2 ;d0: 0 1 8 9 ;d2: 2 3 10 11 vtrn.32 d1, d3 ;d1: 4 5 12 13 ;d3: 6 7 14 15 vtrn.16 d0, d1 ;d0: 0 4 8 12 ;d1: 1 5 9 13 vtrn.16 d2, d3 ;d2: 2 6 10 14 ;d3: 3 7 11 15 ; second for loop vadd.s16 d4, d0, d3 ;a = [0] + [3] vadd.s16 d6, d1, d2 ;b = [1] + [2] vsub.s16 d5, d0, d3 ;d = [0] - [3] vsub.s16 d7, d1, d2 ;c = [1] - [2] vmov.i16 q8, #3 vadd.s16 q0, q2, q3 ; a+b d+c vsub.s16 q1, q2, q3 ; a-b d-c vadd.i16 q0, q0, q8 ;e/f += 3 vadd.i16 q1, q1, q8 ;g/h += 3 vshr.s16 q0, q0, #3 ;e/f >> 3 vshr.s16 q1, q1, #3 ;g/h >> 3 mov r2, #64 add r3, r1, #32 vst1.i16 d0[0], [r1],r2 vst1.i16 d1[0], [r3],r2 vst1.i16 d2[0], [r1],r2 vst1.i16 d3[0], [r3],r2 vst1.i16 d0[1], [r1],r2 vst1.i16 d1[1], [r3],r2 vst1.i16 d2[1], [r1],r2 vst1.i16 d3[1], [r3],r2 vst1.i16 d0[2], [r1],r2 vst1.i16 d1[2], [r3],r2 vst1.i16 d2[2], [r1],r2 vst1.i16 d3[2], [r3],r2 vst1.i16 d0[3], [r1],r2 vst1.i16 d1[3], [r3],r2 vst1.i16 d2[3], [r1] vst1.i16 d3[3], [r3] bx lr ENDP ; |vp8_short_inv_walsh4x4_neon| END