@alsutton Just looked - yep, #defines, typedefs and more syscall wrappers with #pragmas.

Looking at timings for a micro, and nothing like loop unrolling to ruin your timings. Luckily, there is _Pragma to let you put #pragmas in macros, and "GCC unroll 1" to prevent loop unrolling, so you get the nop/subs/bne.n to match expected timing.