RtlFindSetBits

NTSTATUS __fastcall RtlFindSetBits(INT64 a1, UINT64 a2, UINT64 a3){
  unsigned int v3; 
  int v4; 
  unsigned int v5; 
  int v6; 
  int v7; 
  __int64 v8; 
  __int64 v9; 
  int v10; 
  unsigned int v11; 
  unsigned int v12; 
  __int64 v13; 
  unsigned int v14; 
  __int64 v15; 
  unsigned __int64 v16; 
  _QWORD *v17; 
  signed __int64 v18; 
  unsigned __int64 v19; 
  unsigned int v20; 
  bool v21; 
  NTSTATUS v22; 
  unsigned int v24; 
  int v25; 
  _QWORD *v26; 
  bool v27; 
  __int64 v28; 
  unsigned int v29; 
  unsigned __int64 v30; 
  __int64 v31; 
  int v32; 
  unsigned int v33; 
  __int64 v34; 
  unsigned __int64 v35; 
  int v36; 
  char v37; 
  _QWORD *v38; 
  __int64 v39; 
  unsigned int v40; 
  __int64 v41; 
  __int64 v42; 
  __int64 v43; 
  __int64 v44; 
  __int64 v45; 
  int v46; 

  v3 = *(_DWORD *)a1;
  v4 = a3;
  v5 = a2;
  v6 = (unsigned int)a3 < *(_DWORD *)a1 ? a3 : 0;
  v7 = *(_DWORD *)a1 - 1;
  if( !(_DWORD)a2 )
    return v6 & 0xFFFFFFF8;
  v8 = *(_QWORD *)(a1 + 8);
  v45 = v8;
  v9 = v8 & 4;
  v44 = v9;
  v10 = v9 != 0 ? 0x20 : 0;
  while( 1 )
  {
    v11 = v10 + v7;
    v12 = v10 + v6;
    v13 = v8 - (v9 != 0 ? 4 : 0);
    if( v7 - v6 + 1 < v5 )
    {
LABEL_16:
      v20 = -1;
      goto LABEL_17;
    }
    v14 = v11 - v5 + 1;
    v15 = (1i64 << (v12 & 0x3F)) - 1;
    v16 = v13 + 8 * ((unsigned __int64)v14 >> 6);
    v17 = (_QWORD *)(v13 + 8 * ((unsigned __int64)v12 >> 6));
    v18 = ~*v17 | v15;
    if( v5 > 0x7F )
    {
      v35 = v16 + 8;
      if( (v14 & 0x3F) == 0 )
        v35 = v13 + 8 * ((unsigned __int64)(v11 - v5 + 1) >> 6);
      if( !v18 )
      {
        v36 = 0;
        goto LABEL_53;
      }
      if( *++v17 != -1i64 )
        goto LABEL_59;
      v27 = !_BitScanReverse64((unsigned __int64 *)&v43, v18);
      if( !v27 )
      {
        v36 = 63 - v43;
        goto LABEL_53;
      }
LABEL_78:
      v36 = 64;
LABEL_53:
      while( 1 )
      {
        v20 = ((unsigned int)(((__int64)v17 - v13) >> 3) << 6) - v36;
        if( v20 > v14 )
          goto LABEL_16;
        v37 = v5 - v36;
        v38 = &v17[(unsigned __int64)(v5 - v36) >> 6];
        while( ++v17 != v38 )
        {
          if( *v17 != -1i64 )
            goto LABEL_59;
        }
        v40 = v37 & 0x3F;
        if( !v40 )
          goto LABEL_12;
        v27 = !_BitScanForward64((unsigned __int64 *)&v41, ~*v17);
        if( v27 )
          LODWORD(v41) = 64;
        if( (unsigned int)v41 >= v40 )
          goto LABEL_12;
        do
        {
LABEL_59:
          if( (unsigned __int64)v17 > v35 )
            goto LABEL_16;
          ++v17;
        }
        while( *v17 != -1i64 );
        v46 &= ~*(_DWORD *)v17;
        v27 = !_BitScanReverse64((unsigned __int64 *)&v39, ~*(v17 - 1));
        if( v27 )
          goto LABEL_78;
        v36 = 63 - v39;
      }
    }
    if( v5 >= 0x40 )
    {
      while( 1 )
      {
        while( 1 )
        {
          while( v18 < 0 )
          {
            if( (unsigned __int64)++v17 > v16 )
              goto LABEL_16;
            v18 = ~*v17;
          }
          v27 = !_BitScanReverse64((unsigned __int64 *)&v31, v18);
          if( v27 )
            v32 = 64;
          else
            v32 = 63 - v31;
          v20 = (((unsigned int)(((__int64)v17 - v13) >> 3) + 1) << 6) - v32;
          if( v20 > v14 )
            goto LABEL_16;
          v33 = v5 - v32;
          if( v5 == v32 )
            goto LABEL_12;
          v18 = ~*++v17;
          if( v33 >= 0x40 )
            break;
LABEL_45:
          v27 = !_BitScanForward64((unsigned __int64 *)&v34, v18);
          if( v27 )
            LODWORD(v34) = 64;
          if( (unsigned int)v34 >= v33 )
            goto LABEL_12;
        }
        if( *v17 == -1i64 )
        {
          v33 -= 64;
          if( !v33 )
            goto LABEL_12;
          v18 = ~*++v17;
          goto LABEL_45;
        }
      }
    }
    if( v5 > 1 )
    {
      v25 = 0;
      v26 = (_QWORD *)(v13 + 8 * ((unsigned __int64)v11 >> 6));
      while( v18 != -1 )
      {
LABEL_23:
        v27 = !_BitScanForward64((unsigned __int64 *)&v28, v18);
        if( v27 )
          LODWORD(v28) = 64;
        if( v25 + (int)v28 >= v5 )
        {
          LODWORD(v30) = -v25;
LABEL_30:
          v20 = ((unsigned int)(((__int64)v17 - v13) >> 3) << 6) + v30;
          v21 = v20 <= v14;
          goto LABEL_11;
        }
        v29 = v5;
        v30 = ~v18;
        while( 1 )
        {
          v30 &= v30 >> (v29 >> 1);
          if( !v30 )
            break;
          v29 -= v29 >> 1;
          if( v29 <= 1 )
          {
            _BitScanForward64(&v30, v30);
            goto LABEL_30;
          }
        }
        if( v17 == v26 )
          goto LABEL_16;
        v27 = !_BitScanReverse64((unsigned __int64 *)&v42, v18);
        if( v27 )
          v25 = 64;
        else
          v25 = 63 - v42;
        v18 = ~*++v17;
      }
      while( 1 )
      {
        if( (unsigned __int64)++v17 > v16 )
          goto LABEL_16;
        v18 = ~*v17;
        if( *v17 )
        {
          v25 = 0;
          goto LABEL_23;
        }
      }
    }
    while( v18 == -1 )
    {
      if( (unsigned __int64)++v17 > v16 )
        goto LABEL_16;
      v18 = ~*v17;
    }
    _BitScanForward64(&v19, ~v18);
    v20 = v19 + ((unsigned int)(((__int64)v17 - v13) >> 3) << 6);
    v21 = v20 <= v14;
LABEL_11:
    if( !v21 )
      goto LABEL_16;
LABEL_12:
    if( v20 != -1 )
      break;
LABEL_17:
    if( !v6 )
      break;
    v9 = v44;
    v24 = v5 + v4;
    v8 = v45;
    if( v5 + v4 > v3 )
      v24 = v3;
    v7 = v24 - 1;
    v6 = 0;
  }
  v22 = v20 - v10;
  if( v20 == -1 )
    return -1;
  return v22;
}

Referenced by: