ExAcquireFastMutexUnsafe

VOID *__stdcall ExAcquireFastMutexUnsafe(PFAST_MUTEX FastMutex){
  _ETHREAD *CurrentThread; 
  __int64 v2; 
  __int64 v4; 
  char v5; 
  NTSTATUS SessionId; 
  VOID *result; 
  bool v8; 
  unsigned __int8 AbOrphanedEntrySummary; 
  UINT64 a3; 

  CurrentThread = (_ETHREAD *)KeGetCurrentThread();
  v2 = 0i64;
  LODWORD(a3) = 0;
  --CurrentThread->Tcb.SpecialApcDisable;
  if( ++CurrentThread->Tcb.AbAllocationRegionCount != 1 )
    KeBugCheckEx(0x192u, CurrentThread, FastMutex, (PVOID)KeGetCurrentIrql(), 0i64);
  LOBYTE(v4) = CurrentThread->Tcb.AbEntrySummary;
  if( !(_BYTE)v4 )
  {
    if( !CurrentThread->Tcb.AbOrphanedEntrySummary )
      goto LABEL_18;
    AbOrphanedEntrySummary = CurrentThread->Tcb.AbOrphanedEntrySummary;
    CurrentThread->Tcb.AbOrphanedEntrySummary = 0;
    LOBYTE(v4) = AbOrphanedEntrySummary | CurrentThread->Tcb.AbEntrySummary;
  }
  v5 = v4;
  _BitScanForward((unsigned int *)&v4, (unsigned __int8)v4);
  CurrentThread->Tcb.AbEntrySummary = v5 & ~(1 << v4);
  v2 = (__int64)&CurrentThread->Tcb.LockEntries[v4];
  if( !v2 )
  {
LABEL_18:
    _interlockedbittestandset((volatile signed __int32 *)&CurrentThread->Tcb.116 + 1, 0x10u);
    goto LABEL_8;
  }
  if( (unsigned __int64)FastMutex >= 0xFFFF800000000000ui64
    && *((_BYTE *)&stru_140C4DB30 + (((unsigned __int64)FastMutex >> 39) & 0x1FF) + 6872) == 1 )
  {
    SessionId = MmGetSessionIdEx(CurrentThread->Tcb.ApcState.Process);
  }
  else
  {
    SessionId = -1;
  }
  *(_DWORD *)(v2 + 40) = SessionId;
  *(_QWORD *)(v2 + 32) = (unsigned __int64)FastMutex & 0x7FFFFFFFFFFFFFFCi64;
LABEL_8:
  --CurrentThread->Tcb.AbAllocationRegionCount;
  KiAbThreadRemoveBoosts(&CurrentThread->Tcb, FastMutex, &a3);
  v8 = CurrentThread->Tcb.SpecialApcDisable++ == -1;
  if( v8
    && ($F25F8C4BA33AF922A5F1AF68CD89DDDF *)CurrentThread->Tcb.ApcState.ApcListHead[0].Flink != &CurrentThread->Tcb.152 )
  {
    KiCheckForKernelApcDelivery();
  }
  if( !_interlockedbittestandreset(&FastMutex->Count, 0) )
    ExpAcquireFastMutexContended(FastMutex, (VOID *)v2);
  if( v2 )
    *(_BYTE *)(v2 + 26) |= 1u;
  FastMutex->Owner = CurrentThread;
  return result;
}

Referenced by: