Optimization settings for UB in XCode

Just playing around with these settings when compiling msp externals and thought the results might be interesting to others.

The UB SDK sets the optimisation level to Os (Fastest / Smallest) for deployment (rather than O3 - fastest - which apple say may produce larger binaries).

I discovered the following:

1 - The O3 Faster setting may produce code that runs quite a lot faster. As an example I compiled the plus~ project in the SDK with this setting and also with the Os (Fastest/Smallest) setting. I then tested a patch filled only with plus~ objects (both inlets connected to a signal)

Under Os - CPU was at 56-58%

Under O3 - CPU was at 39-42%

Which I think is a pretty decent saving. In both cases the external came out as being 36K.

I also had the same result with the code for times~ from an older SDK (also

2 - On the other hand...

A couple of more complex msp externals were marginally slower with this setting (and a bit bigger as well)

These observations hold true for intel only (Compiled and tested on a MBP only).

So it looks like it might be trying different settings for each individual case.

Alex