On Wed, Mar 10, 2010 at 8:54 PM, Siarhei Siamashka <siarhei.siamas...@gmail.com> wrote: [...] > I wonder why the compiler does not use real NEON instructions with -ffast-math > option, it should be quite useful even for scalar code. > > something like: > > vld1.32 {d0[0]}, [r0] > vadd.f32 d0, d0, d0 > vst1.32 {d0[0]}, [r0] > > instead of: > > flds s0, [r0] > fadds s0, s0, s0 > fsts s0, [r0] > > for: > > *float_ptr = *float_ptr + *float_ptr; > > At least NEON is pipelined and should be a lot faster on more complex code > examples where it can actually benefit from pipelining. On x86, SSE2 is used > quite nicely for floating point math.
Even if fast-math is known to break some rules, it only breaks C rules IIRC. OTOH, NEON FP has no support for NaN and other nice things from IEEE754. Anyway you're perhaps looking for -mfpu=neon, no? Laurent _______________________________________________ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers