[FRIAM] Q_rsqrt() vs 1/sqrt()

[Stephen Taylor]

Because the hardware environment has changed, and the tradeoffs on integer
and floating-point arithmetic are different. (Like it says in the Wikipedia
article.)  Out of order execution might be messing up your measurements,
too.

---------- message ----------
From: "uǝlƃ ↙↙↙" <gepropella at gmail.com>
To: FriAM <friam at redfish.com>
Cc:
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Date: Thu, 7 Jan 2021 15:24:15 -0800
Subject: [FRIAM] Q_rsqrt() vs 1/sqrt()
https://en.wikipedia.org/wiki/Fast_inverse_square_root

So, why is Q_rsqrt() *slower* than 1/sqrt()?

1/sqrt() took 0.294771 s
Q_rsqrt() took 0.51579 s

-- 
↙↙↙ uǝlƃ
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