Double vs float on the iPhone

Question

I have just heard that the iphone cannot do double natively thereby making them much slower that regular float.

Is this true? Evidence?

I am very interested

Answer 1

This slide show gives insight in why there isn't good floating point and why there is (the vector floating point unit). Apparently, it is important you check the "thumb mode" which influences whether or not floating point support is on. This is not always an improvement. It shows how to find the right instructions in the assembly code.

It also depends on what version of the phone you want to run your code. The most recent one seems "more capable" in doing floating point math.

EDIT: here's an interesting read on floating point optimizations on the ARM with VFP and NEON SSE.