| ; |
| ; 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_fast_fdct4x4_neon| |
| |
| ARM |
| REQUIRE8 |
| PRESERVE8 |
| |
| AREA ||.text||, CODE, READONLY, ALIGN=2 |
| ;void vp8_fast_fdct4x4_c(short *input, short *output, int pitch); |
| ;NOTE: |
| ;The input *src_diff. src_diff is calculated as: |
| ;diff_ptr[c] = src_ptr[c] - pred_ptr[c]; (in Subtract* function) |
| ;In which *src_ptr and *pred_ptr both are unsigned char. |
| ;Therefore, *src_diff should be in the range of [-255, 255]. |
| ;CAUTION: |
| ;The input values of 25th block are set in vp8_build_dcblock function, which are out of [-255, 255]. |
| ;But, VP8 encoder only uses vp8_short_fdct4x4_c for 25th block, not vp8_fast_fdct4x4_c. That makes |
| ;it ok for assuming *input in [-255, 255] in vp8_fast_fdct4x4_c, but not ok in vp8_short_fdct4x4_c. |
| |
| |vp8_fast_fdct4x4_neon| PROC |
| vld1.16 {d2}, [r0], r2 ;load input |
| ldr r12, _ffdct_coeff_ |
| vld1.16 {d3}, [r0], r2 |
| vld1.16 {d4}, [r0], r2 |
| vld1.16 {d0}, [r12] |
| vld1.16 {d5}, [r0], r2 |
| |
| ;First for-loop |
| ;transpose d2, d3, d4, d5. Then, d2=ip[0], d3=ip[1], d4=ip[2], d5=ip[3] |
| vtrn.32 d2, d4 |
| vtrn.32 d3, d5 |
| vtrn.16 d2, d3 |
| vtrn.16 d4, d5 |
| |
| vadd.s16 d6, d2, d5 ;ip[0]+ip[3] |
| vadd.s16 d7, d3, d4 ;ip[1]+ip[2] |
| vsub.s16 d8, d3, d4 ;ip[1]-ip[2] |
| vsub.s16 d9, d2, d5 ;ip[0]-ip[3] |
| vshl.i16 q3, q3, #1 ; a1, b1 |
| vshl.i16 q4, q4, #1 ; c1, d1 |
| |
| vadd.s16 d10, d6, d7 ;temp1 = a1 + b1 |
| vsub.s16 d11, d6, d7 ;temp2 = a1 - b1 |
| |
| vqdmulh.s16 q6, q5, d0[1] |
| vqdmulh.s16 q8, q4, d0[0] |
| vqdmulh.s16 q7, q4, d0[2] |
| |
| vshr.s16 q6, q6, #1 |
| vshr.s16 q8, q8, #1 |
| vshr.s16 q7, q7, #1 ;d14:temp1 = ( c1 * x_c3)>>16; d15:temp1 = (d1 * x_c3)>>16 |
| vadd.s16 q8, q4, q8 ;d16:temp2 = ((c1 * x_c1)>>16) + c1; d17:temp2 = ((d1 * x_c1)>>16) + d1 |
| |
| vadd.s16 d2, d10, d12 ;op[0] = ((temp1 * x_c2 )>>16) + temp1 |
| vadd.s16 d4, d11, d13 ;op[2] = ((temp2 * x_c2 )>>16) + temp2 |
| vadd.s16 d3, d14, d17 ;op[1] = temp1 + temp2 -- q is not necessary, just for protection |
| vsub.s16 d5, d15, d16 ;op[3] = temp1 - temp2 |
| |
| ;Second for-loop |
| ;transpose d2, d3, d4, d5. Then, d2=ip[0], d3=ip[4], d4=ip[8], d5=ip[12] |
| vtrn.32 d2, d4 |
| vtrn.32 d3, d5 |
| vtrn.16 d2, d3 |
| vtrn.16 d4, d5 |
| |
| vadd.s16 d6, d2, d5 ;a1 = ip[0]+ip[12] |
| vadd.s16 d7, d3, d4 ;b1 = ip[4]+ip[8] |
| vsub.s16 d8, d3, d4 ;c1 = ip[4]-ip[8] |
| vsub.s16 d9, d2, d5 ;d1 = ip[0]-ip[12] |
| |
| vadd.s16 d10, d6, d7 ;temp1 = a1 + b1 |
| vsub.s16 d11, d6, d7 ;temp2 = a1 - b1 |
| |
| |
| vqdmulh.s16 q6, q5, d0[1] |
| vqdmulh.s16 q8, q4, d0[0] |
| vqdmulh.s16 q7, q4, d0[2] |
| |
| vshr.s16 q6, q6, #1 |
| vshr.s16 q8, q8, #1 |
| vshr.s16 q7, q7, #1 ;d14:temp1 = ( c1 * x_c3)>>16; d15:temp1 = (d1 * x_c3)>>16 |
| vadd.s16 q8, q4, q8 ;d16:temp2 = ((c1 * x_c1)>>16) + c1; d17:temp2 = ((d1 * x_c1)>>16) + d1 |
| |
| vadd.s16 d2, d10, d12 ;a2 = ((temp1 * x_c2 )>>16) + temp1 |
| vadd.s16 d4, d11, d13 ;c2 = ((temp2 * x_c2 )>>16) + temp2 |
| vadd.s16 d3, d14, d17 ;b2 = temp1 + temp2 -- q is not necessary, just for protection |
| vsub.s16 d5, d15, d16 ;d2 = temp1 - temp2 |
| |
| vclt.s16 q3, q1, #0 |
| vclt.s16 q4, q2, #0 |
| |
| vsub.s16 q1, q1, q3 |
| vsub.s16 q2, q2, q4 |
| |
| vshr.s16 q1, q1, #1 |
| vshr.s16 q2, q2, #1 |
| |
| vst1.16 {q1, q2}, [r1] |
| |
| bx lr |
| |
| ENDP |
| |
| ;----------------- |
| AREA fastfdct_dat, DATA, READONLY |
| ;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 ... |
| _ffdct_coeff_ |
| DCD ffdct_coeff |
| ffdct_coeff |
| ; 60547 = 0xEC83 |
| ; 46341 = 0xB505 |
| ; 25080 = 0x61F8 |
| DCD 0xB505EC83, 0x000061F8 |
| |
| END |
