The ARM Advanced Single Instruction Multiple Data (SIMD) Extension, also known as NEON technology, is a 64/128-bit hybrid SIMD architecture developed by ARM to accelerate the performance of multimedia and signal processing applications. NEON is implemented as part of the processor, but has its own execution pipelines and a register bank that is distinct from the ARM register bank. Key features include aligned and unaligned data access, support for integer, fixed-point and single-precision floating point data types, tight coupling to the ARM core, and a large register file with multiple views. NEON instructions are available in both ARM and Thumb-2.

The ARM compiler provides support for Cortex™ processors equipped with a NEON unit. To generate NEON instructions you must specify a Cortex processor that includes NEON technology on the command line, for example, --cpu=Cortex-A8. There is no NEON support for architectures before ARMv7.

See Appendix E Using NEON Support in the Compiler Reference Guide for more information.