[fpc-devel] Faster InitObject

[Tommi Prami]

 >
>
> > Incl.   Self.   Called     Function
> > 29.78   29.72    26M        SYSTEM_FILLCHAR$formal$INT64$BYTE
> > 19.07   19.07    123M       SYSTEM_MOVE$formal$formal$INT64
> >  3.63    3.63    70M       SYSTEM_SYSGETMEM_FIXED$QWORD$$POINTER
> > ....
> >
> > The main caller of FillChar function is
> > system_TObject_$__NewInstance$$TObject which called Fillchar 26 Million
> > times.
> >
> > NewInstance method in TObject calls InitInstance which is an inline
> > function and defined as follows:
> >
> >       class function TObject.InitInstance(instance : pointer) :
> > tobject; {$ifdef SYSTEMINLINE} inline; {$ENDIF}
> >
> >         begin
> >            { the size is saved at offset 0 }
> >            fillchar(instance^, InstanceSize, 0);
> >            { insert VMT pointer into the new created memory area }
> >            { (in class methods self contains the VMT!)           }
> >            ppointer(instance)^:=pointer(self);
> >            if PVmt(self)^.vIntfTable <> @emptyintf then
> >              InitInterfacePointers(self,instance);
> >            InitInstance:=TObject(Instance);
> >         end;
> >
> > My question is do we need to call fillchar in InitInstance? Or Is there
> > any way to avoid calling InitInstance?
>
> Yes, FillChar is needed, because a class instance is guaranteed to 
> have Bennett initialized with zero before the first constructor is 
> called (this way the fields are basically initialized by 0, Nil or '' 
> depending on the field type).
>
>

But still...

Any improvement done in the Creating and Freeing an Objects would be 
welcome :)

We need the FillChar there, but if the object creation could be 
optimized even a little bit, it would benefit almost all the code. Some 
more than others... But still...

-Tee-