Boost C++ Libraries of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is the documentation for a snapshot of the develop branch, built from commit c5994560ca.
Lookup Table?

The ideal way to optimize the constants would be to have a carefully-tuned lookup-table instead of the get_max_count function, but 4 tuning variables is simpler, get_max_count enforces worst-case performance minimization rules, and such a lookup table would be difficult to optimize for cross-platform performance.

Alternatively, get_max_count could be used to generate a static lookup table. This hasn't been done due to concerns about cross-platform compatibility and flexibility.