You must use RVCT 3.1 or later, or ARM Compiler 4.1 or later, with a valid NEON compiler license.
To generate NEON instructions from C or C++ code, you must specify the following compiler options:
a target
--cputhat has NEON capability, for example Cortex-A8, Cortex-A9, or Cortex-A15--vectorizeto enable NEON vectorization-O2(default) or-O3optimization level-Otimeto optimize for performance instead of code size.
You can also use --diag_warning=optimizations to
obtain useful diagnostics from the compiler on what it can and cannot
optimize or vectorize. For example:
armcc --cpu Cortex-A8 --vectorize -O3 -Otime --diag_warning=optimizations source.c
See also- Tasks
- Concepts
- Reference
Compiler Reference:
- Other information
Introducing the ARM Compiler toolchain:
PDF version