Agreed, I'm only interested in hardfloat versus softfloat ABI...
Dave
On Wed, 2011-09-07 at 23:25 +0100, Mans Rullgard wrote:
On 7 September 2011 23:01, David Rusling david.rusling@linaro.org wrote:
I'm a little confused. There's two comparisons to be made.
The comparison between vfp enabled in all cases, comparing using the soft float ABI with using the hard float ABI means that you'll identify the effect of moving VFP registers in and out of integer registers to make function call (soft float ABI) versus using them directly (hard float ABI).
The comparision of using VFP at all versus only using integer emulation of floating point is separate and different.
Both have an effect, the effects manifest themselves differently.
I don't think we need to run any tests at all to know the outcome of VFP (regardless of ABI) versus emulation.
In addition to the above, a few applications have both floating-point and fixed-point implementations of the same algorithms with a compile- time choice of which is used. In these cases, a speed comparison is of course of interest, although one must keep in mind that the output is likely to be different, floating-point often having better accuracy.