| ; |
| ; 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_short_idct4x4llm_neon| |
| ARM |
| REQUIRE8 |
| PRESERVE8 |
| |
| AREA ||.text||, CODE, READONLY, ALIGN=2 |
| |
| ;************************************************************* |
| ;void vp8_short_idct4x4llm_c(short *input, short *output, int pitch) |
| ;r0 short * input |
| ;r1 short * output |
| ;r2 int pitch |
| ;************************************************************* |
| ;static const int cospi8sqrt2minus1=20091; |
| ;static const int sinpi8sqrt2 =35468; |
| ;static const int rounding = 0; |
| ;Optimization note: The resulted data from dequantization are signed 13-bit data that is |
| ;in the range of [-4096, 4095]. This allows to use "vqdmulh"(neon) instruction since |
| ;it won't go out of range (13+16+1=30bits<32bits). This instruction gives the high half |
| ;result of the multiplication that is needed in IDCT. |
| |
| |vp8_short_idct4x4llm_neon| PROC |
| ldr r12, _idct_coeff_ |
| vld1.16 {q1, q2}, [r0] |
| vld1.16 {d0}, [r12] |
| |
| vswp d3, d4 ;q2(vp[4] vp[12]) |
| |
| vqdmulh.s16 q3, q2, d0[2] |
| vqdmulh.s16 q4, q2, d0[0] |
| |
| vqadd.s16 d12, d2, d3 ;a1 |
| vqsub.s16 d13, d2, d3 ;b1 |
| |
| vshr.s16 q3, q3, #1 |
| vshr.s16 q4, q4, #1 |
| |
| vqadd.s16 q3, q3, q2 ;modify since sinpi8sqrt2 > 65536/2 (negtive number) |
| vqadd.s16 q4, q4, q2 |
| |
| ;d6 - c1:temp1 |
| ;d7 - d1:temp2 |
| ;d8 - d1:temp1 |
| ;d9 - c1:temp2 |
| |
| vqsub.s16 d10, d6, d9 ;c1 |
| vqadd.s16 d11, d7, d8 ;d1 |
| |
| vqadd.s16 d2, d12, d11 |
| vqadd.s16 d3, d13, d10 |
| vqsub.s16 d4, d13, d10 |
| vqsub.s16 d5, d12, d11 |
| |
| vtrn.32 d2, d4 |
| vtrn.32 d3, d5 |
| vtrn.16 d2, d3 |
| vtrn.16 d4, d5 |
| |
| vswp d3, d4 |
| |
| vqdmulh.s16 q3, q2, d0[2] |
| vqdmulh.s16 q4, q2, d0[0] |
| |
| vqadd.s16 d12, d2, d3 ;a1 |
| vqsub.s16 d13, d2, d3 ;b1 |
| |
| vshr.s16 q3, q3, #1 |
| vshr.s16 q4, q4, #1 |
| |
| vqadd.s16 q3, q3, q2 ;modify since sinpi8sqrt2 > 65536/2 (negtive number) |
| vqadd.s16 q4, q4, q2 |
| |
| vqsub.s16 d10, d6, d9 ;c1 |
| vqadd.s16 d11, d7, d8 ;d1 |
| |
| vqadd.s16 d2, d12, d11 |
| vqadd.s16 d3, d13, d10 |
| vqsub.s16 d4, d13, d10 |
| vqsub.s16 d5, d12, d11 |
| |
| vrshr.s16 d2, d2, #3 |
| vrshr.s16 d3, d3, #3 |
| vrshr.s16 d4, d4, #3 |
| vrshr.s16 d5, d5, #3 |
| |
| add r3, r1, r2 |
| add r12, r3, r2 |
| add r0, r12, r2 |
| |
| vtrn.32 d2, d4 |
| vtrn.32 d3, d5 |
| vtrn.16 d2, d3 |
| vtrn.16 d4, d5 |
| |
| vst1.16 {d2}, [r1] |
| vst1.16 {d3}, [r3] |
| vst1.16 {d4}, [r12] |
| vst1.16 {d5}, [r0] |
| |
| bx lr |
| |
| ENDP |
| |
| ;----------------- |
| AREA idct4x4_dat, DATA, READWRITE ;read/write by default |
| ;Data section with name data_area is specified. DCD reserves space in memory for 48 data. |
| ;One word each is reserved. Label filter_coeff can be used to access the data. |
| ;Data address: filter_coeff, filter_coeff+4, filter_coeff+8 ... |
| _idct_coeff_ |
| DCD idct_coeff |
| idct_coeff |
| DCD 0x4e7b4e7b, 0x8a8c8a8c |
| |
| ;20091, 20091, 35468, 35468 |
| |
| END |
