anchor.diff:  
          PrefixCharClasses:TFLREPrefixCharClasses;
          CountPrefixCharClasses:longint;
  -       CountObviousPrefixCharClasses:longint;
  +       AveragePrefixCharClassesVariance:longint;
          PrefixPatternBitMasks:TFLRECharPatternBitMasks;
   
          ByteMap:TFLREByteMap;
  
positive.code:    end;
    end;
   end;
  var ThreadIndex,Count,Index:longint;
      CurrentThreadList,NewThreadList,TemporaryThreadList:PThreadList;
      CurrentThread:PThread;
      Instruction:PFLREInstruction;
  
negative.code:       inc(Count);
       end;
      end;
      inc(TotalCount,Count);
     end;
     if CountPrefixCharClasses>0 then begin
      AveragePrefixCharClassesVariance:=(TotalCount+((CountPrefixCharClasses+1) div 2)) div CountPrefixCharClasses;
     end else begin
      AveragePrefixCharClassesVariance:=255;
     end;
     DFAFastBeginningSearch:=AveragePrefixCharClassesVariance<32;
  
     CompilePrefixPattern;
  
  