0aa9b52efa
This optimized version is primarily targeted at cortex-a15. Tested on all nexus devices using the system/extras/libc_test strlen test. Tested alignments from 1 to 32 that are powers of 2. Tested that strlen does not cross page boundaries at all alignments. Speed improvements listed below: cortex-a15 - Sizes >= 32 bytes, ~75% improvement. - Sizes >= 1024 bytes, ~250% improvement. cortex-a9 - Sizes >= 32 bytes, ~75% improvement. - Sizes >= 1024 bytes, ~85% improvement. krait - Sizes >= 32 bytes, ~95% improvement. - Sizes >= 1024 bytes, ~160% improvement. Merge from internal master. (cherry-picked from 2fc071797743b88a9a47427d46baed7c7b24f4d2) Change-Id: I1ceceb4e745fd68e9d946f96d1d42e0cdaff6ccf