[C++-sig] Profiling object instantiation... a preliminary report

[Ullrich Koethe]

David Abrahams wrote:
> 
> <<But then, why wouldn't it be possible to place a function into the
> table
> that does the lookup in another table (that just contains time-critical
> functions with C++ linkage) instead of a dictionary? >>
> 
> Yes. What makes you think you can do better than Python's highly-tuned
> dictionaries for this purpose?
> 

I don't want to replace Python's mechanism for all functions - only a
fixed set of special functions will get special treatment. Since the set
is fixed, those function pointers can be stored in an array rather than
a hash table, so that lookup will be faster, no matter how clever the
hash is implemented. 

slot for special function => forward to function array
slot for not so special function => forward to function dictionary

Whether the gain is worth the trouble is another question, though...

Ulli
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