This is a series of patch to enhance _Hashtable insertion operations
that I'd like to see in gcc 14. I've already submitted something similar
a couple of months ago but it is quite a revisited version.
1/5 Is adding benches to show the impact of the different optimizations
2/5 Implementation inconsistencies fixes already submitted individually.
3/5 Avoid redundant rehash check on unordered_multi[map/set]
4/5 Extend the small size optimization to all methods
5/5 Insert node for empty bucket after last rather than before-begin
The last patch of the series will require to bump version namespace but
it is already plan for the cxx11 abi adoption in this mode.
I still need to run the benches that I've already run previously on this
new version of the patches.
Successfully tested in normal and gnu-versioned namespace modes.
François