; ; 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_fast_fdct8x4_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_fdct8x4_neon| PROC vld1.16 {q1}, [r0], r2 ;load input ldr r12, _ffdct8_coeff_ vld1.16 {q2}, [r0], r2 vld1.16 {q3}, [r0], r2 vld1.16 {d0}, [r12] vld1.16 {q4}, [r0], r2 ;First for-loop ;transpose d2, d4, d6, d8. Then, d2=ip[0], d4=ip[1], d6=ip[2], d8=ip[3] ;transpose d3, d5, d7, d9. Then, d3=ip[0], d5=ip[1], d7=ip[2], d9=ip[3] vtrn.32 d2, d6 vtrn.32 d3, d7 vtrn.32 d4, d8 vtrn.32 d5, d9 vtrn.16 d2, d4 vtrn.16 d3, d5 vtrn.16 d6, d8 vtrn.16 d7, d9 vadd.s16 d10, d2, d8 ;ip[0]+ip[3] vadd.s16 d11, d4, d6 ;ip[1]+ip[2] vsub.s16 d12, d4, d6 ;ip[1]-ip[2] vsub.s16 d13, d2, d8 ;ip[0]-ip[3] vadd.s16 d22, d3, d9 vadd.s16 d23, d5, d7 vsub.s16 d24, d5, d7 vsub.s16 d25, d3, d9 vshl.i16 q5, q5, #1 ; a1, b1 vshl.i16 q6, q6, #1 ; c1, d1 vshl.i16 q1, q11, #1 vshl.i16 q2, q12, #1 vadd.s16 d14, d10, d11 ;temp1 = a1 + b1 vsub.s16 d15, d10, d11 ;temp2 = a1 - b1 vadd.s16 d24, d2, d3 vsub.s16 d25, d2, d3 vqdmulh.s16 q8, q7, d0[1] vqdmulh.s16 q13, q12, d0[1] vqdmulh.s16 q10, q6, d0[0] vqdmulh.s16 q15, q2, d0[0] vqdmulh.s16 q9, q6, d0[2] vqdmulh.s16 q14, q2, d0[2] vshr.s16 q8, q8, #1 vshr.s16 q13, q13, #1 vshr.s16 q10, q10, #1 vshr.s16 q15, q15, #1 vshr.s16 q9, q9, #1 ;d18:temp1 = ( c1 * x_c3)>>16; d19:temp1 = (d1 * x_c3)>>16 vshr.s16 q14, q14, #1 ;d28:temp1 = ( c1 * x_c3)>>16; d29:temp1 = (d1 * x_c3)>>16 vadd.s16 q10, q6, q10 ;d20:temp2 = ((c1 * x_c1)>>16) + c1; d21:temp2 = ((d1 * x_c1)>>16) + d1 vadd.s16 q15, q2, q15 ;d30:temp2 = ((c1 * x_c1)>>16) + c1; d31:temp2 = ((d1 * x_c1)>>16) + d1 vadd.s16 d2, d14, d16 ;op[0] = ((temp1 * x_c2 )>>16) + temp1 vadd.s16 d3, d24, d26 ;op[0] = ((temp1 * x_c2 )>>16) + temp1 vadd.s16 d6, d15, d17 ;op[2] = ((temp2 * x_c2 )>>16) + temp2 vadd.s16 d7, d25, d27 ;op[2] = ((temp2 * x_c2 )>>16) + temp2 vadd.s16 d4, d18, d21 ;op[1] = temp1 + temp2 -- q is not necessary, just for protection vadd.s16 d5, d28, d31 ;op[1] = temp1 + temp2 -- q is not necessary, just for protection vsub.s16 d8, d19, d20 ;op[3] = temp1 - temp2 vsub.s16 d9, d29, d30 ;op[3] = temp1 - temp2 ;Second for-loop ;transpose d2, d4, d6, d8. Then, d2=ip[0], d4=ip[4], d6=ip[8], d8=ip[12] ;transpose d3, d5, d7, d9. Then, d3=ip[0], d5=ip[4], d7=ip[8], d9=ip[12] vtrn.32 d2, d6 vtrn.32 d3, d7 vtrn.32 d4, d8 vtrn.32 d5, d9 vtrn.16 d2, d4 vtrn.16 d3, d5 vtrn.16 d6, d8 vtrn.16 d7, d9 vadd.s16 d10, d2, d8 ;a1 = ip[0]+ip[12] vadd.s16 d11, d4, d6 ;b1 = ip[4]+ip[8] vsub.s16 d12, d4, d6 ;c1 = ip[4]-ip[8] vsub.s16 d13, d2, d8 ;d1 = ip[0]-ip[12] vadd.s16 d2, d3, d9 vadd.s16 d4, d5, d7 vsub.s16 d24, d5, d7 vsub.s16 d25, d3, d9 vadd.s16 d14, d10, d11 ;temp1 = a1 + b1 vsub.s16 d15, d10, d11 ;temp2 = a1 - b1 vadd.s16 d22, d2, d4 vsub.s16 d23, d2, d4 vqdmulh.s16 q8, q7, d0[1] vqdmulh.s16 q13, q11, d0[1] vqdmulh.s16 q10, q6, d0[0] vqdmulh.s16 q15, q12, d0[0] vqdmulh.s16 q9, q6, d0[2] vqdmulh.s16 q14, q12, d0[2] vshr.s16 q8, q8, #1 vshr.s16 q13, q13, #1 vshr.s16 q10, q10, #1 vshr.s16 q15, q15, #1 vshr.s16 q9, q9, #1 ;d18:temp1 = ( c1 * x_c3)>>16; d19:temp1 = (d1 * x_c3)>>16 vshr.s16 q14, q14, #1 ;d28:temp1 = ( c1 * x_c3)>>16; d29:temp1 = (d1 * x_c3)>>16 vadd.s16 q10, q6, q10 ;d20:temp2 = ((c1 * x_c1)>>16) + c1; d21:temp2 = ((d1 * x_c1)>>16) + d1 vadd.s16 q15, q12, q15 ;d30:temp2 = ((c1 * x_c1)>>16) + c1; d31:temp2 = ((d1 * x_c1)>>16) + d1 vadd.s16 d2, d14, d16 ;a2 = ((temp1 * x_c2 )>>16) + temp1 vadd.s16 d6, d22, d26 ;a2 = ((temp1 * x_c2 )>>16) + temp1 vadd.s16 d4, d15, d17 ;c2 = ((temp2 * x_c2 )>>16) + temp2 vadd.s16 d8, d23, d27 ;c2 = ((temp2 * x_c2 )>>16) + temp2 vadd.s16 d3, d18, d21 ;b2 = temp1 + temp2 -- q is not necessary, just for protection vadd.s16 d7, d28, d31 ;b2 = temp1 + temp2 -- q is not necessary, just for protection vsub.s16 d5, d19, d20 ;d2 = temp1 - temp2 vsub.s16 d9, d29, d30 ;d2 = temp1 - temp2 vclt.s16 q5, q1, #0 vclt.s16 q6, q2, #0 vclt.s16 q7, q3, #0 vclt.s16 q8, q4, #0 vsub.s16 q1, q1, q5 vsub.s16 q2, q2, q6 vsub.s16 q3, q3, q7 vsub.s16 q4, q4, q8 vshr.s16 q1, q1, #1 vshr.s16 q2, q2, #1 vshr.s16 q3, q3, #1 vshr.s16 q4, q4, #1 vst1.16 {q1, q2}, [r1]! vst1.16 {q3, q4}, [r1] bx lr ENDP ;----------------- AREA fastfdct8x4_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 ... _ffdct8_coeff_ DCD ffdct8_coeff ffdct8_coeff ; 60547 = 0xEC83 ; 46341 = 0xB505 ; 25080 = 0x61F8 DCD 0xB505EC83, 0x000061F8 END