[libre-riscv-dev] FP transcendentals (trigonometry, root/exp/log) proposal

MitchAlsup MitchAlsup at aol.com
Wed Aug 7 23:36:17 BST 2019

Is this proposal going to <eventually> include::

a) statement on required/delivered numeric accuracy per transcendental ?
b) a reserve on the OpCode space for the double precision equivalents ?
c) a statement on <approximate> execution time ?

You may have more transcendentals than necessary::
1) for example all of the inverse hyperbolic can be calculated to GRAPHICs 
numeric quality with short sequences of already existing transcendentals
..... ASINH( x ) = ln( x + SQRT(x**2+1) )

2) LOG(x) = LOGP1(x) + 1.0
... EXP(x) = EXPM1(x-1.0)

That is:: LOGP1 and EXPM1 provide greater precision (especially when the 
result is near zero) than their sister functions, and the compiler can 
easily add the additional instruction to the instruction stream where 

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