IopCalculateStackInformation

CHAR __fastcall IopCalculateStackInformation(INT64 a1, INT64 a2, UINT64 *a3, UINT64 *a4){
  CHAR v4; 
  UINT64 v7; 
  UINT64 v8; 
  UINT64 v9; 
  INT64 v10; 
  UINT64 v11; 
  unsigned int v12; 
  void *v13; 
  int MaxValidMemorySize; 
  v4 = 0;
  if( a1 && (*(_DWORD *)(a1 + 120) & 0x20000) != 0 )
  {
    v7 = *(_QWORD *)(a2 + 152);
    v8 = *(_QWORD *)(a1 + 48);
    v9 = *(_QWORD *)(a1 + 56);
    if( v8 > v7 || v7 >= v9 )
    {
      *a3 = *(_QWORD *)(a1 + 48);
      if( (*((_BYTE *)KeGetPcr() + 12972) & 1) != 0 && a1 != *((_QWORD *)KeGetCurrentPrcb() + 3) )
      {
        v10 = *((_QWORD *)KeGetPcr() + 1618);
        if( KiIsAddressRangeValid(v10, 80i64) )
        {
          v11 = *(_QWORD *)(v10 + 64);
          if( v8 <= v11 && v11 < v9 )
            *a3 = v11;
        }
      }
    }
    else
    {
      *a3 = v7;
    }
    v12 = v9 - *(_DWORD *)a3;
    v13 = (void *)*a3;
    *(_DWORD *)a4 = v12;
    MaxValidMemorySize = IopGetMaxValidMemorySize(v13, v12);
    *(_DWORD *)a4 = MaxValidMemorySize;
    if( *a3 && MaxValidMemorySize )
      return 1;
  }
  return v4;
}

Referenced by: