> Is SSE(2) inherently faster then (at least in real-world implementations) than
> x87, even when you don't vectorize?  Would I be able to expect any speedup 
> from
> going from x87 to SSE(2) for code that has a decent amount of implicit 
> instruction
> level parallelism but wasn't explicitly vectorized either by me or the 
> compiler?

There is a couple of interesting scalar instructions in SSE

- cvttss2si : floorf without modifying the rounding mode (SSE2)
- 32-bit float square root and inverse square root
- min, max

SSE doesn't suffer from denormalization which can be very useful.
I personnally don't mind if the compiler use them or not, provided one can use 
inline assembly :)



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