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Re: Optimising std::find on x86 and PPC

Paolo Carlini wrote:

Chris Jefferson wrote:

Then the current loop optimise doesn't do loop unrolling to something more like:


Besided what Gaby and Benjamin already replied, out of curiosity, what the loop
unroller is doing, right now?!? Nothing!?!

Yep, with -funroll-loops -O3 on last week's CVS, if I give:
int* check(int* a,int* b)
{
for(;a<b;++a)
  if(*a==1) return a;
return a;
}

Then it does no optimising at all. I suspect if it could unroll this by itself, then it would deal with the processor-specific fixes itself.

Chris

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