As I already noted, I have played a little with valgrind and kcachegrind, and measured some new code against ideal, hand-written code. The first thing I noted is amount of time spent in malloc and free functions. Another thing is that time spent in single wrapper function became significiant when that function is called about millions of times. Let's look closer at WMCreateObject function. It is simple wrapper over malloc with few checks. In the nearest future this function will be called everywhere. Why not make it inline?
Another issue, that eats time on many calls is checks for null-pointers. I don't like the idea of terminating application once I got out of memory. It's application's job to decide what to do. Construction functions return NULL if memory allocation fails. If it doesn't fail they're filling allocated memory with some data. And those checks are really taking time. Generally I don't need more than one check for single object construction call.
The solution I came is to divide API. Internal API will be set on small, mostly inline functions, mostly without any checks. This doesn't mean it would call malloc and than unconditionally write something in returned pointer. Memory allocation and filling object with data is just different functions. With this structure I will be able to allocate memory, check for NULL, and call multiple filling functions without penalty for additional checks.
