RtlFindSetBitsAndClear

NTSTATUS __fastcall RtlFindSetBitsAndClear(INT64 a1, UINT64 a2, UINT64 a3){
  unsigned int v3; 
  int v4; 
  UINT32 v5; 
  _RTL_BITMAP *v6; 
  int v7; 
  int v8; 
  unsigned int v9; 
  __int64 v10; 
  int v11; 
  unsigned int v12; 
  unsigned int v13; 
  __int64 v14; 
  unsigned int v15; 
  unsigned int v16; 
  __int64 v17; 
  unsigned __int64 v18; 
  _QWORD *v19; 
  signed __int64 v20; 
  unsigned __int64 v21; 
  int v22; 
  __int64 v23; 
  bool v24; 
  __int64 v25; 
  char v26; 
  _QWORD *v27; 
  unsigned int v28; 
  __int64 v29; 
  unsigned int v30; 
  int v31; 
  _QWORD *v32; 
  __int64 v33; 
  unsigned int v34; 
  unsigned __int64 v35; 
  __int64 v36; 
  int v37; 
  unsigned int v38; 
  __int64 v39; 
  __int64 v40; 
  bool v41; 
  unsigned __int64 v42; 
  int v44; 
  __int64 v45; 
  int v47; 
  int v48; 

  v47 = a3;
  v3 = *(_DWORD *)a1;
  v4 = a3;
  v5 = a2;
  v6 = (_RTL_BITMAP *)a1;
  v7 = (unsigned int)a3 < *(_DWORD *)a1 ? a3 : 0;
  v8 = *(_DWORD *)a1 - 1;
  if( !(_DWORD)a2 )
  {
    v9 = v7 & 0xFFFFFFF8;
    goto LABEL_79;
  }
  v10 = *(_QWORD *)(a1 + 8);
  v45 = v10;
  v11 = (v10 & 4) != 0 ? 0x20 : 0;
  while( 1 )
  {
    v12 = v11 + v8;
    v13 = v11 + v7;
    v14 = v10 - ((v45 & 4) != 0 ? 4 : 0);
    if( v8 - v7 + 1 < v5 )
    {
      v15 = -1;
      goto LABEL_29;
    }
    v16 = v12 - v5 + 1;
    v17 = (1i64 << (v13 & 0x3F)) - 1;
    v18 = v14 + 8 * ((unsigned __int64)v16 >> 6);
    v19 = (_QWORD *)(v14 + 8 * ((unsigned __int64)v13 >> 6));
    v20 = ~*v19 | v17;
    if( v5 > 0x7F )
    {
      v21 = v18 + 8;
      if( (v16 & 0x3F) == 0 )
        v21 = v14 + 8 * ((unsigned __int64)(v12 - v5 + 1) >> 6);
      if( v20 )
      {
        v23 = ~*++v19;
        if( *v19 != -1i64 )
          goto LABEL_15;
        v48 &= v23;
        v24 = !_BitScanReverse64((unsigned __int64 *)&v23, v20);
        if( v24 )
LABEL_13:
          v22 = 64;
        else
          v22 = 63 - v23;
      }
      else
      {
        v22 = 0;
      }
LABEL_19:
      v15 = ((unsigned int)(((__int64)v19 - v14) >> 3) << 6) - v22;
      if( v15 <= v16 )
      {
        v26 = v5 - v22;
        v27 = &v19[(unsigned __int64)(v5 - v22) >> 6];
        while( ++v19 != v27 )
        {
          if( *v19 != -1i64 )
            goto LABEL_15;
        }
        v28 = v26 & 0x3F;
        if( !v28 )
          goto LABEL_27;
        v24 = !_BitScanForward64((unsigned __int64 *)&v29, ~*v19);
        if( v24 )
          LODWORD(v29) = 64;
        if( (unsigned int)v29 >= v28 )
          goto LABEL_27;
LABEL_15:
        while( (unsigned __int64)v19 <= v21 )
        {
          if( *++v19 == -1i64 )
          {
            v44 &= ~*(_DWORD *)v19;
            v24 = !_BitScanReverse64((unsigned __int64 *)&v25, ~*(v19 - 1));
            if( v24 )
              goto LABEL_13;
            v22 = 63 - v25;
            goto LABEL_19;
          }
        }
      }
      goto LABEL_68;
    }
    if( v5 >= 0x40 )
    {
      while( 1 )
      {
        while( 1 )
        {
          while( v20 < 0 )
          {
            if( (unsigned __int64)++v19 > v18 )
              goto LABEL_68;
            v20 = ~*v19;
          }
          v24 = !_BitScanReverse64((unsigned __int64 *)&v36, v20);
          if( v24 )
            v37 = 64;
          else
            v37 = 63 - v36;
          v15 = (((unsigned int)(((__int64)v19 - v14) >> 3) + 1) << 6) - v37;
          if( v15 > v16 )
            goto LABEL_68;
          v38 = v5 - v37;
          if( v5 == v37 )
            goto LABEL_27;
          v20 = ~*++v19;
          if( v38 >= 0x40 )
            break;
LABEL_59:
          v24 = !_BitScanForward64((unsigned __int64 *)&v39, v20);
          if( v24 )
            LODWORD(v39) = 64;
          if( (unsigned int)v39 >= v38 )
            goto LABEL_27;
        }
        if( *v19 == -1i64 )
        {
          v38 -= 64;
          if( !v38 )
            goto LABEL_27;
          v20 = ~*++v19;
          goto LABEL_59;
        }
      }
    }
    if( v5 <= 1 )
    {
      while( v20 == -1 )
      {
        if( (unsigned __int64)++v19 > v18 )
          goto LABEL_68;
        v20 = ~*v19;
      }
      _BitScanForward64(&v42, ~v20);
      v15 = v42 + ((unsigned int)(((__int64)v19 - v14) >> 3) << 6);
      v41 = v15 <= v16;
LABEL_71:
      if( v41 )
      {
LABEL_27:
        if( v15 != -1 )
          break;
        goto LABEL_28;
      }
    }
    else
    {
      v31 = 0;
      v32 = (_QWORD *)(v14 + 8 * ((unsigned __int64)v12 >> 6));
      while( v20 != -1 )
      {
LABEL_40:
        v24 = !_BitScanForward64((unsigned __int64 *)&v33, v20);
        if( v24 )
          LODWORD(v33) = 64;
        if( v31 + (int)v33 >= v5 )
        {
          LODWORD(v35) = -v31;
LABEL_70:
          v15 = ((unsigned int)(((__int64)v19 - v14) >> 3) << 6) + v35;
          v41 = v15 <= v16;
          goto LABEL_71;
        }
        v34 = v5;
        v35 = ~v20;
        while( 1 )
        {
          v35 &= v35 >> (v34 >> 1);
          if( !v35 )
            break;
          v34 -= v34 >> 1;
          if( v34 <= 1 )
          {
            _BitScanForward64(&v35, v35);
            goto LABEL_70;
          }
        }
        if( v19 == v32 )
          goto LABEL_68;
        v24 = !_BitScanReverse64((unsigned __int64 *)&v40, v20);
        if( v24 )
          v31 = 64;
        else
          v31 = 63 - v40;
        v20 = ~*++v19;
      }
      while( (unsigned __int64)++v19 <= v18 )
      {
        v20 = ~*v19;
        if( *v19 )
        {
          v31 = 0;
          goto LABEL_40;
        }
      }
    }
LABEL_68:
    v15 = -1;
LABEL_28:
    v4 = v47;
LABEL_29:
    if( !v7 )
      break;
    v10 = v45;
    v30 = v5 + v4;
    if( v5 + v4 > v3 )
      v30 = v3;
    v8 = v30 - 1;
    v7 = 0;
  }
  v6 = (_RTL_BITMAP *)a1;
  v9 = v15 - v11;
  if( v15 == -1 )
    v9 = -1;
LABEL_79:
  if( v9 != -1 )
    RtlClearBits(v6, v9, v5);
  return v9;
}

Referenced by: