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Re: Why you are wrong [Was: On linux kernel packaging issue]

On Mon, 10 Nov 2003, Joe Wreschnig wrote:

> A program that is CPU-bound *and* can be encoded more efficiently will
> benefit from compiler optimizations. Some CPU bound things just aren't
> going to be helped much by vectorization, instruction reordering, etc. I
> mean, integer multiply is integer multiply.

But if the target cpu supports pipelining, and has multiple multiplication
units(which means it can do them in parallel), or can do a 128bit multiple, or
1 64 bit multiple, at once, then it's more efficient to do a partial loop
unroll, and thereby have faster code, because of more efficient parallization.

(sorry, read Dr. Dobbs last week).

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