Operation Costs in CPU Clock Cycles

Re:Operation Costs in CPU Clock Cycles by chrisseaton on Friday November 11, 2016 @05:03PM (#12934899)

Is it that simple for virtual methods in complex class hierarchies? If the class hierarchy isn't linear, how can you assign simple absolute vtable indices for methods?

[ Parent | on HN ]

Re:Operation Costs in CPU Clock Cycles by dom0 on Friday November 11, 2016 @05:26PM (#12935050)

Yes it is. The C++ ABI defines how any permitted inheritance hierarchy is mapped into a surjective, ordered set of vtables. Also, calls into methods of other classes in the hierarchy offset the this pointer accordingly.

It feels counterintuitive that these two mechanisms are sufficient; but they are.

[ Parent | on HN ]