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Re: Optimising std::find on x86 and PPC
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.