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A comment on Did any processor implement an integer square root instruction?. Parent comment

Re:Did any processor implement an integer square root instru... by colechristensen on Sunday April 07, 2024 @12:54PM (#39962022)
Inverse square root is for normalizing vectors particularly in computer graphics calculations, it needs to be run a whole lot very fast.

https://en.m.wikipedia.org/wiki/Fast_inverse_square_root#Mot...

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Re:Did any processor implement an integer square root instru... by hinkley on Sunday April 07, 2024 @03:44PM (#39963235)
Famously the magic constant in the Quake engine that nobody remembers inventing.

That article does say there’s an SSE instruction rsqrtss that is better.

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