Re: discussion reset! thumb2/thumbee code as on armv7-a
> On Thursday 15 July 2010 21:11:50 Paul Brook wrote:
> > Choice of ISA is independent of the ABI. Generally speaking ARM code is
> > still faster. This is another instance of where you want multiple
> > builds of the same package within the same port, so users can choose
> > between
> > speed (-marm -O2) and size (-mthumb -Os) optimized builds.
> That's still not entirely true. In a benchmark for Eigen3 library -with
> NEON enabled- the binary (bench_gemm) compiled with -mthumb gave
> ~0.1GFLOPS more (0.93, vs 0.83GFLOPS) than the one without -both on
> hardfp, btw. The reason is simple, there simply was more room in the L1/L2
> caches for data and the code was equally fast to process them.
> So, thumb is actually not a bad thing for speed either.
Depends on your benchmark. The last set I saw showed ARM mode still wins on