Re: How to profile a VC++ program?

fastgo@gmail.com wrote:


Getter functions returning classes are hard to optimize, and often the
convenient getter functions are suboptimal, because returning a class by
value involves making a copy.

If it's possible, you can try to return values by reference, like this:

class A
{
public:
    std::string SlowGetter() const { return s; }
    const std::string& FastGetter() const { return s; }
private:
    std::string s;
};

It's not always possible, like in this case:
    std::string GetPathName() const { return dir + "\" + path; }

In this case a less convenient getter function has a chance to be faster:
    void GetPathName(std::string& s)
    {
       s.reserve(dir.size() + 1 + path.size());
       s = dir; s += "\"; s += path;
    }

Andrei Alexandrescu has an article about optimizing return values from
functions:

http://www.ddj.com/dept/cpp/184403855

Tom