HalpDmaFinalizeDoubleBufferingDisposition

VOID __stdcall HalpDmaFinalizeDoubleBufferingDisposition(){
  void *v0; 
  char *v1; 
  NTSTATUS v2; 
  void *PoolWithTag; 
  UINT64 v4; 
  UINT8 *v5; 
  __int64 v6; 
  unsigned __int64 v7; 
  ULONG ResultLength; 
  UINT8 dst[4]; 
  void *KeyHandle; 
  struct _UNICODE_STRING ValueName; 
  __int64 v12[2]; 
  struct _OBJECT_ATTRIBUTES ObjectAttributes; 
  char KeyValueInformation[16]; 
  *(&ObjectAttributes.Length + 1) = 0;
  memset(&ObjectAttributes.Attributes + 1, 0, 20);
  ResultLength = 0;
  v12[1] = (__int64)L"\\Registry\\MACHINE\\SYSTEM\\CurrentControlSet\\Control\\Session Manager\\Memory Management";
  v0 = 0i64;
  KeyHandle = 0i64;
  ObjectAttributes.RootDirectory = 0i64;
  ValueName.Buffer = L"DynamicMemory";
  v12[0] = 11141288i64;
  ObjectAttributes.ObjectName = (_UNICODE_STRING *)v12;
  *(_QWORD *)&ValueName.Length = 1835034i64;
  ObjectAttributes.Length = 48;
  ObjectAttributes.Attributes = 576;
  if( !ZwOpenKey(&KeyHandle, 0x20019u, &ObjectAttributes) )
  {
    v1 = KeyValueInformation;
    v2 = ZwQueryValueKey(KeyHandle, &ValueName, KeyValuePartialInformation, KeyValueInformation, 0x10u, &ResultLength);
    if( (v2 == -2147483643 || v2 == -1073741789) && ResultLength > 0x10 )
    {
      PoolWithTag = ExAllocatePoolWithTag(PagedPool, ResultLength, 0x206C6148ui64);
      v0 = PoolWithTag;
      if( !PoolWithTag )
      {
LABEL_7:
        if( KeyHandle )
          ZwClose(KeyHandle);
        return;
      }
      v1 = (char *)PoolWithTag;
      v2 = ZwQueryValueKey(KeyHandle, &ValueName, KeyValuePartialInformation, PoolWithTag, ResultLength, &ResultLength);
    }
    if( !v2 )
    {
      v4 = *((unsigned int *)v1 + 2);
      v5 = (UINT8 *)(v1 + 12);
      if( (unsigned int)v4 < 4 )
      {
        *(_DWORD *)dst = 0;
        memmove(dst, v5, v4);
        v6 = *(unsigned int *)dst;
      }
      else
      {
        v6 = *(unsigned int *)v5;
      }
      v7 = (v6 << 30) - 1;
      if( v7 > HalpMaximumPhysicalMemoryAddress )
        HalpMaximumPhysicalMemoryAddress = v7;
    }
    if( v0 )
      ExFreePoolWithTag(v0, 0x206C6148u);
    goto LABEL_7;
  }
}

Referenced by: