dsputil_h264_template_altivec.c

ffmpeg源码分析

  srcbis += srcStride;
  const vector unsigned char srcM1a = vec_ld(0, srcbis);
  const vector unsigned char srcM1b = vec_ld(16, srcbis);
  const vector unsigned char srcM1 = vec_perm(srcM1a, srcM1b, perm);
  srcbis += srcStride;
  const vector unsigned char srcP0a = vec_ld(0, srcbis);
  const vector unsigned char srcP0b = vec_ld(16, srcbis);
  const vector unsigned char srcP0 = vec_perm(srcP0a, srcP0b, perm);
  srcbis += srcStride;
  const vector unsigned char srcP1a = vec_ld(0, srcbis);
  const vector unsigned char srcP1b = vec_ld(16, srcbis);
  const vector unsigned char srcP1 = vec_perm(srcP1a, srcP1b, perm);
  srcbis += srcStride;
  const vector unsigned char srcP2a = vec_ld(0, srcbis);
  const vector unsigned char srcP2b = vec_ld(16, srcbis);
  const vector unsigned char srcP2 = vec_perm(srcP2a, srcP2b, perm);
  srcbis += srcStride;

  vector signed short srcM2ssA = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcM2);
  vector signed short srcM2ssB = (vector signed short)vec_mergel((vector unsigned char)vzero, srcM2);
  vector signed short srcM1ssA = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcM1);
  vector signed short srcM1ssB = (vector signed short)vec_mergel((vector unsigned char)vzero, srcM1);
  vector signed short srcP0ssA = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcP0);
  vector signed short srcP0ssB = (vector signed short)vec_mergel((vector unsigned char)vzero, srcP0);
  vector signed short srcP1ssA = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcP1);
  vector signed short srcP1ssB = (vector signed short)vec_mergel((vector unsigned char)vzero, srcP1);
  vector signed short srcP2ssA = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcP2);
  vector signed short srcP2ssB = (vector signed short)vec_mergel((vector unsigned char)vzero, srcP2);

  for (i = 0 ; i < 16 ; i++) {
    const vector unsigned char srcP3a = vec_ld(0, srcbis);
    const vector unsigned char srcP3b = vec_ld(16, srcbis);
    const vector unsigned char srcP3 = vec_perm(srcP3a, srcP3b, perm);
    const vector signed short srcP3ssA = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcP3);
    const vector signed short srcP3ssB = (vector signed short)vec_mergel((vector unsigned char)vzero, srcP3);
    srcbis += srcStride;

    const vector signed short sum1A = vec_adds(srcP0ssA, srcP1ssA);
    const vector signed short sum1B = vec_adds(srcP0ssB, srcP1ssB);
    const vector signed short sum2A = vec_adds(srcM1ssA, srcP2ssA);
    const vector signed short sum2B = vec_adds(srcM1ssB, srcP2ssB);
    const vector signed short sum3A = vec_adds(srcM2ssA, srcP3ssA);
    const vector signed short sum3B = vec_adds(srcM2ssB, srcP3ssB);

    srcM2ssA = srcM1ssA;
    srcM2ssB = srcM1ssB;
    srcM1ssA = srcP0ssA;
    srcM1ssB = srcP0ssB;
    srcP0ssA = srcP1ssA;
    srcP0ssB = srcP1ssB;
    srcP1ssA = srcP2ssA;
    srcP1ssB = srcP2ssB;
    srcP2ssA = srcP3ssA;
    srcP2ssB = srcP3ssB;

    const vector signed short pp1A = vec_mladd(sum1A, v20ss, v16ss);
    const vector signed short pp1B = vec_mladd(sum1B, v20ss, v16ss);

    const vector signed short pp2A = vec_mladd(sum2A, v5ss, (vector signed short)vzero);
    const vector signed short pp2B = vec_mladd(sum2B, v5ss, (vector signed short)vzero);

    const vector signed short pp3A = vec_add(sum3A, pp1A);
    const vector signed short pp3B = vec_add(sum3B, pp1B);

    const vector signed short psumA = vec_sub(pp3A, pp2A);
    const vector signed short psumB = vec_sub(pp3B, pp2B);

    const vector signed short sumA = vec_sra(psumA, v5us);
    const vector signed short sumB = vec_sra(psumB, v5us);

    const vector unsigned char sum = vec_packsu(sumA, sumB);

    const vector unsigned char dst1 = vec_ld(0, dst);
    const vector unsigned char dst2 = vec_ld(16, dst);
    const vector unsigned char vdst = vec_perm(dst1, dst2, vec_lvsl(0, dst));

    vector unsigned char fsum;
    OP_U8_ALTIVEC(fsum, sum, vdst);

    const vector unsigned char rsum = vec_perm(fsum, fsum, dstperm);
    const vector unsigned char fdst1 = vec_sel(dst1, rsum, dstmask);
    const vector unsigned char fdst2 = vec_sel(rsum, dst2, dstmask);

    vec_st(fdst1, 0, dst);
    vec_st(fdst2, 16, dst);

    dst += dstStride;
  }
  POWERPC_PERF_STOP_COUNT(PREFIX_h264_qpel16_v_lowpass_num, 1);
}

/* this code assume stride % 16 == 0 *and* tmp is properly aligned */
static void PREFIX_h264_qpel16_hv_lowpass_altivec(uint8_t * dst, int16_t * tmp, uint8_t * src, int dstStride, int tmpStride, int srcStride) {
  POWERPC_PERF_DECLARE(PREFIX_h264_qpel16_hv_lowpass_num, 1);
  POWERPC_PERF_START_COUNT(PREFIX_h264_qpel16_hv_lowpass_num, 1);
  register int i;
  const vector signed int vzero = vec_splat_s32(0);
  const vector unsigned char permM2 = vec_lvsl(-2, src);
  const vector unsigned char permM1 = vec_lvsl(-1, src);
  const vector unsigned char permP0 = vec_lvsl(+0, src);
  const vector unsigned char permP1 = vec_lvsl(+1, src);
  const vector unsigned char permP2 = vec_lvsl(+2, src);
  const vector unsigned char permP3 = vec_lvsl(+3, src);
  const vector signed short v20ss = vec_sl(vec_splat_s16(5),vec_splat_u16(2));
  const vector unsigned int v10ui = vec_splat_u32(10);
  const vector signed short v5ss = vec_splat_s16(5);
  const vector signed short v1ss = vec_splat_s16(1);
  const vector signed int v512si = vec_sl(vec_splat_s32(1),vec_splat_u32(9));
  const vector unsigned int v16ui = vec_sl(vec_splat_u32(1),vec_splat_u32(4));

  register int align = ((((unsigned long)src) - 2) % 16);

  src -= (2 * srcStride);

  for (i = 0 ; i < 21 ; i ++) {
    vector unsigned char srcM2, srcM1, srcP0, srcP1, srcP2, srcP3;
    vector unsigned char srcR1 = vec_ld(-2, src);
    vector unsigned char srcR2 = vec_ld(14, src);

    switch (align) {
    default: {
      srcM2 = vec_perm(srcR1, srcR2, permM2);
      srcM1 = vec_perm(srcR1, srcR2, permM1);
      srcP0 = vec_perm(srcR1, srcR2, permP0);
      srcP1 = vec_perm(srcR1, srcR2, permP1);
      srcP2 = vec_perm(srcR1, srcR2, permP2);
      srcP3 = vec_perm(srcR1, srcR2, permP3);
    } break;
    case 11: {
      srcM2 = vec_perm(srcR1, srcR2, permM2);
      srcM1 = vec_perm(srcR1, srcR2, permM1);
      srcP0 = vec_perm(srcR1, srcR2, permP0);
      srcP1 = vec_perm(srcR1, srcR2, permP1);
      srcP2 = vec_perm(srcR1, srcR2, permP2);
      srcP3 = srcR2;
    } break;
    case 12: {
      vector unsigned char srcR3 = vec_ld(30, src);
      srcM2 = vec_perm(srcR1, srcR2, permM2);
      srcM1 = vec_perm(srcR1, srcR2, permM1);
      srcP0 = vec_perm(srcR1, srcR2, permP0);
      srcP1 = vec_perm(srcR1, srcR2, permP1);
      srcP2 = srcR2;
      srcP3 = vec_perm(srcR2, srcR3, permP3);
    } break;
    case 13: {
      vector unsigned char srcR3 = vec_ld(30, src);
      srcM2 = vec_perm(srcR1, srcR2, permM2);
      srcM1 = vec_perm(srcR1, srcR2, permM1);
      srcP0 = vec_perm(srcR1, srcR2, permP0);
      srcP1 = srcR2;
      srcP2 = vec_perm(srcR2, srcR3, permP2);
      srcP3 = vec_perm(srcR2, srcR3, permP3);
    } break;
    case 14: {
      vector unsigned char srcR3 = vec_ld(30, src);
      srcM2 = vec_perm(srcR1, srcR2, permM2);
      srcM1 = vec_perm(srcR1, srcR2, permM1);
      srcP0 = srcR2;
      srcP1 = vec_perm(srcR2, srcR3, permP1);
      srcP2 = vec_perm(srcR2, srcR3, permP2);
      srcP3 = vec_perm(srcR2, srcR3, permP3);
    } break;
    case 15: {
      vector unsigned char srcR3 = vec_ld(30, src);
      srcM2 = vec_perm(srcR1, srcR2, permM2);
      srcM1 = srcR2;
      srcP0 = vec_perm(srcR2, srcR3, permP0);
      srcP1 = vec_perm(srcR2, srcR3, permP1);
      srcP2 = vec_perm(srcR2, srcR3, permP2);
      srcP3 = vec_perm(srcR2, srcR3, permP3);
    } break;
    }

    const vector signed short srcP0A = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcP0);
    const vector signed short srcP0B = (vector signed short)vec_mergel((vector unsigned char)vzero, srcP0);
    const vector signed short srcP1A = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcP1);
    const vector signed short srcP1B = (vector signed short)vec_mergel((vector unsigned char)vzero, srcP1);

    const vector signed short srcP2A = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcP2);
    const vector signed short srcP2B = (vector signed short)vec_mergel((vector unsigned char)vzero, srcP2);
    const vector signed short srcP3A = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcP3);
    const vector signed short srcP3B = (vector signed short)vec_mergel((vector unsigned char)vzero, srcP3);

    const vector signed short srcM1A = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcM1);
    const vector signed short srcM1B = (vector signed short)vec_mergel((vector unsigned char)vzero, srcM1);
    const vector signed short srcM2A = (vector signed short)vec_mergeh((vector unsigned char)vzero, srcM2);
    const vector signed short srcM2B = (vector signed short)vec_mergel((vector unsigned char)vzero, srcM2);

    const vector signed short sum1A = vec_adds(srcP0A, srcP1A);
    const vector signed short sum1B = vec_adds(srcP0B, srcP1B);
    const vector signed short sum2A = vec_adds(srcM1A, srcP2A);
    const vector signed short sum2B = vec_adds(srcM1B, srcP2B);
    const vector signed short sum3A = vec_adds(srcM2A, srcP3A);
    const vector signed short sum3B = vec_adds(srcM2B, srcP3B);

    const vector signed short pp1A = vec_mladd(sum1A, v20ss, sum3A);
    const vector signed short pp1B = vec_mladd(sum1B, v20ss, sum3B);

    const vector signed short pp2A = vec_mladd(sum2A, v5ss, (vector signed short)vzero);
    const vector signed short pp2B = vec_mladd(sum2B, v5ss, (vector signed short)vzero);

    const vector signed short psumA = vec_sub(pp1A, pp2A);
    const vector signed short psumB = vec_sub(pp1B, pp2B);

    vec_st(psumA, 0, tmp);
    vec_st(psumB, 16, tmp);

    src += srcStride;
    tmp += tmpStride; /* int16_t*, and stride is 16, so it's OK here */
  }

  const vector unsigned char dstperm = vec_lvsr(0, dst);
  const vector unsigned char neg1 = (const vector unsigned char)vec_splat_s8(-1);
  const vector unsigned char dstmask = vec_perm((const vector unsigned char)vzero, neg1, dstperm);
  const vector unsigned char mperm = (const vector unsigned char)
    AVV(0x00, 0x08, 0x01, 0x09, 0x02, 0x0A, 0x03, 0x0B,
        0x04, 0x0C, 0x05, 0x0D, 0x06, 0x0E, 0x07, 0x0F);

  int16_t *tmpbis = tmp - (tmpStride * 21);

  vector signed short tmpM2ssA = vec_ld(0, tmpbis);
  vector signed short tmpM2ssB = vec_ld(16, tmpbis);
  tmpbis += tmpStride;
  vector signed short tmpM1ssA = vec_ld(0, tmpbis);
  vector signed short tmpM1ssB = vec_ld(16, tmpbis);
  tmpbis += tmpStride;
  vector signed short tmpP0ssA = vec_ld(0, tmpbis);
  vector signed short tmpP0ssB = vec_ld(16, tmpbis);
  tmpbis += tmpStride;
  vector signed short tmpP1ssA = vec_ld(0, tmpbis);
  vector signed short tmpP1ssB = vec_ld(16, tmpbis);
  tmpbis += tmpStride;
  vector signed short tmpP2ssA = vec_ld(0, tmpbis);
  vector signed short tmpP2ssB = vec_ld(16, tmpbis);
  tmpbis += tmpStride;

  for (i = 0 ; i < 16 ; i++) {
    const vector signed short tmpP3ssA = vec_ld(0, tmpbis);
    const vector signed short tmpP3ssB = vec_ld(16, tmpbis);
    tmpbis += tmpStride;

    const vector signed short sum1A = vec_adds(tmpP0ssA, tmpP1ssA);
    const vector signed short sum1B = vec_adds(tmpP0ssB, tmpP1ssB);
    const vector signed short sum2A = vec_adds(tmpM1ssA, tmpP2ssA);
    const vector signed short sum2B = vec_adds(tmpM1ssB, tmpP2ssB);
    const vector signed short sum3A = vec_adds(tmpM2ssA, tmpP3ssA);
    const vector signed short sum3B = vec_adds(tmpM2ssB, tmpP3ssB);

    tmpM2ssA = tmpM1ssA;
    tmpM2ssB = tmpM1ssB;
    tmpM1ssA = tmpP0ssA;
    tmpM1ssB = tmpP0ssB;
    tmpP0ssA = tmpP1ssA;
    tmpP0ssB = tmpP1ssB;
    tmpP1ssA = tmpP2ssA;
    tmpP1ssB = tmpP2ssB;
    tmpP2ssA = tmpP3ssA;
    tmpP2ssB = tmpP3ssB;

    const vector signed int pp1Ae = vec_mule(sum1A, v20ss);
    const vector signed int pp1Ao = vec_mulo(sum1A, v20ss);
    const vector signed int pp1Be = vec_mule(sum1B, v20ss);
    const vector signed int pp1Bo = vec_mulo(sum1B, v20ss);

    const vector signed int pp2Ae = vec_mule(sum2A, v5ss);
    const vector signed int pp2Ao = vec_mulo(sum2A, v5ss);
    const vector signed int pp2Be = vec_mule(sum2B, v5ss);
    const vector signed int pp2Bo = vec_mulo(sum2B, v5ss);

    const vector signed int pp3Ae = vec_sra((vector signed int)sum3A, v16ui);
    const vector signed int pp3Ao = vec_mulo(sum3A, v1ss);
    const vector signed int pp3Be = vec_sra((vector signed int)sum3B, v16ui);
    const vector signed int pp3Bo = vec_mulo(sum3B, v1ss);

    const vector signed int pp1cAe = vec_add(pp1Ae, v512si);
    const vector signed int pp1cAo = vec_add(pp1Ao, v512si);
    const vector signed int pp1cBe = vec_add(pp1Be, v512si);
    const vector signed int pp1cBo = vec_add(pp1Bo, v512si);

    const vector signed int pp32Ae = vec_sub(pp3Ae, pp2Ae);
    const vector signed int pp32Ao = vec_sub(pp3Ao, pp2Ao);
    const vector signed int pp32Be = vec_sub(pp3Be, pp2Be);
    const vector signed int pp32Bo = vec_sub(pp3Bo, pp2Bo);

    const vector signed int sumAe = vec_add(pp1cAe, pp32Ae);
    const vector signed int sumAo = vec_add(pp1cAo, pp32Ao);
    const vector signed int sumBe = vec_add(pp1cBe, pp32Be);
    const vector signed int sumBo = vec_add(pp1cBo, pp32Bo);

    const vector signed int ssumAe = vec_sra(sumAe, v10ui);
    const vector signed int ssumAo = vec_sra(sumAo, v10ui);
    const vector signed int ssumBe = vec_sra(sumBe, v10ui);
    const vector signed int ssumBo = vec_sra(sumBo, v10ui);

    const vector signed short ssume = vec_packs(ssumAe, ssumBe);
    const vector signed short ssumo = vec_packs(ssumAo, ssumBo);

    const vector unsigned char sumv = vec_packsu(ssume, ssumo);
    const vector unsigned char sum = vec_perm(sumv, sumv, mperm);

    const vector unsigned char dst1 = vec_ld(0, dst);
    const vector unsigned char dst2 = vec_ld(16, dst);
    const vector unsigned char vdst = vec_perm(dst1, dst2, vec_lvsl(0, dst));

    vector unsigned char fsum;
    OP_U8_ALTIVEC(fsum, sum, vdst);

    const vector unsigned char rsum = vec_perm(fsum, fsum, dstperm);
    const vector unsigned char fdst1 = vec_sel(dst1, rsum, dstmask);
    const vector unsigned char fdst2 = vec_sel(rsum, dst2, dstmask);

    vec_st(fdst1, 0, dst);
    vec_st(fdst2, 16, dst);

    dst += dstStride;
  }
  POWERPC_PERF_STOP_COUNT(PREFIX_h264_qpel16_hv_lowpass_num, 1);
}