[LAD] Android audio plugins

[Olivier Guilyardi]

On 06/29/2011 07:59 PM, Nick Copeland wrote:
>> - Mobile processors generally do NOT have good
>> floating point power. Sometimes by a factor
>> of 1000 flops.
> 
> It can be a factor of 1000 if the binaries are built assuming there is
> an FPU.
> What happens is you get a system call for every failed float operation.
> If the
> toolset is geared to understand that none is available then it generates
> soft
> floating point operations that just occur in the user thread.
> Performance hit
> is about two zeroes less than you are discussing here. Android appears to
> generate softfloat code.

No, when building with Android NDK using the armeabi-v7a ABI, hard floats are
used. This works on ARMv7, which means a lot of devices, and certainly the
majority.


> The ARM
> softfloat overhead is not that great and the coding required to get
> access to the GPUs is suitable that developers will implement them
> for optimisations.

Soft floats are insanely slow on Android in my experience.

You got an FPU on most devices, you can compile for hard floats, activate ARM
NEON if you wish too, and even check for cpu features at runtime. I don't see
why you want to use the GPU for optimization.

--
  Olivier