Optimising std::find on x86 and PPC

[Paolo Carlini]

Chris Jefferson wrote:

> Only one minor point on this.. in 4.0, we really either need our 
> unrolled code, or a better loop optimiser unless we want to take a 40% 
> speed hit on std::find... so if we remove it and they can't get the 
> loop optimiser fixed, either the current version or (I'd perfer, but 
> won't force) the new version I originally posted should go back in.

While waiting for something to happen in the loop unrolling area, I 
would suggest experimenting a bit with 3.3.x (-O2 -funroll-loops) or 
3.4.x (-O2 -fold-unroll-loops) and seeing what happens if the std::find 
loop is simplified to the bare bones on x86-linux and powerpc-darwin.

Paolo.