Fix walks when the prefix doesn't match any strings
Currently, the walk code doesn't check to see if any prefixes matching the string actually exist. --HG-- extra : amend_source : 4bedf30
Replace aligned malloc calls with plain malloc
--HG-- extra : amend_source : 472f1f7
--HG-- extra : amend_source : a37648d
I Don't want to add preprocessor macros for feature testing.
Use a faster "SWAR" algorithm to find MSB.