From Andre@G||||bert @end|ng |rom chu-rouen@|r  Mon Jul 11 13:48:51 2022
From: Andre@G||||bert @end|ng |rom chu-rouen@|r (GILLIBERT, Andre)
Date: Mon, 11 Jul 2022 11:48:51 +0000
Subject: [Rd] Floating point issue
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> From my current experiences, I dare to say that the M1 with all
> its speed is just a tad less reliable numerically than the
> Intel/AMD floating point implementations..


80 bits floating point (FP) numbers are great, but I think we cannot rely on it for the future.
I expect, the marketshare of ARM CPUs to grow. It's hard to predict, but ARM may spread in desktop computers in a timeframe of 10 years, and I would not expect it to gain extended precision FP.
Moreover, performance of FP80 is not a priority of Intel. FP80 in recent Intel microprocessors are very slow when using special representations (NaN, NA, Inf, -Inf) or denormal numbers.

Therefore, it may be wise to update R algorithms to make them work quite well with 64 bits FP.

--
Sincerely
Andr? GILLIBERT

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[Rd] Floating point issue
GILLIBERT, Andre