Enabling NEON on 32-bit ARM

By default, ATLAS will not use ARM32's SIMD vectorization (NEON), since it is not IEEE-compliant. However, you can force its use by adding the following flags to your configure command:
   -Fa al -mfpu=neon -Si ieee 0
Note that NEON only supports single precision, so this will not change accuracy or speed for double precision.

R. Clint Whaley 2016-07-28