We don't need this micro-optimization which just obfuscates the sources
for negligible performance gains. (Un)likeliness of branches in almost
all cases should be derived from profiling, not from hand-written hints,
using profile-guided optimization.
Plenty of bugfixes for Linux kernel later than 3.5 and Ubuntu later than 10.10.
More organized code to improve portability.
Regression tests for Pal to test completeness of implementation.