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Re: gcc 3.5 integration branch proposal


> Yes; this kind of logic is why many people waste a lot of time
> optimising the wrong place in their code.  Logically, deleting
> instructions means the processor has to do less work and therefore
> makes the program faster.  In practise, though, a write to L1 cache
> takes about 1/3 cycle, but a L2 cache miss takes ~100, and so L2 cache
> misses dominate execution time.

I don't dispute this, but when I see memset() in the top ten on a flat
profile, it seems hard to believe that reducing use of memset won't
speed things up.

zw


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