On sexta-feira, 3 de fevereiro de 2017 13:48:46 PST Kevin Kofler wrote: > The overhead compared to using QString will be reduced, but only part of it > (the avoided memory allocation) is really an optimization. The rest of the > "reduced" overhead is because QString will get the same overhead bloated > onto it (copying the entire string). So, sure, technically, QStringView will > have less overhead over QString, but the way you achieved that is > counterproductive. And all this is only valid for very short strings, longer > strings will still behave the same as before, except for the overhead of > the unused SSO array in both cases.
Note how libstdc++ implemented SSO: instead of bit-check and branch, std::__cxx11::string always keeps a pointer to the beginning of the data, only that reflects back to itself. Interestingly, that's what QStringData did in Qt 4. -- Thiago Macieira - thiago.macieira (AT) intel.com Software Architect - Intel Open Source Technology Center _______________________________________________ Development mailing list [email protected] http://lists.qt-project.org/mailman/listinfo/development
