UINT64 __stdcall KeFindFirstSetLeftGroupAffinity(GROUP_AFFINITY *GroupAffinity){
unsigned __int64 Mask;
Mask = GroupAffinity->Mask;
if( !Mask )
return 0xFFFFFFFFi64;
_BitScanReverse64(&Mask, Mask);
return(unsigned int)KiProcessorNumberToIndexMappingTable[64 * GroupAffinity->Group + (unsigned int)Mask];
}