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A comment on Designing a New Rust Class at Stanford: Safety in Systems Programming. Parent comment

Re:Designing a New Rust Class at Stanford: Safety in Systems... by eska on Wednesday October 07, 2020 @05:59PM (#24713259)
I think you should worry. One of my math professors taught us how factoring to a(x+b(x+c*(...))) is a great optimization in an introductory class, because he had no idea about CPU pipelines for example.
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Re:Designing a New Rust Class at Stanford: Safety in Systems... by vladf on Wednesday October 07, 2020 @08:10PM (#24714308)
Horner’s method for polynomial evaluation is used because of numerical stability, not speed.
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Re:Designing a New Rust Class at Stanford: Safety in Systems... by gregod on Thursday October 08, 2020 @09:36AM (#24718971)
Could you elaborate?

I'm working on a project where the evaluation of a 4th degree polynomial is on the hot path. My micro benchmark (evaluating two polynomials + little bit of addition) shows that using simple Horner's rule is already somewhat faster, and implementing Horner's rule with fused-mul-add is more than twice as fast.

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