[libre-riscv-dev] daily kan-ban update, 22jul2020

[Luke Kenneth Casson Leighton]

On Thursday, July 23, 2020, Jacob Lifshay <programmerjake at gmail.com> wrote:

>
> for soc, we can copy the test case generation logic from DivPipeCore's
> tests in ieee754fpu since that covers waaay more cases (nicely
> exponentially distributed too) but is also deterministic. it covers the
> cases:
> for all 0 <= a < 2^8 and 0 <= b < 64:
> the case a << b if b < 64 - 8
> and the case ~(a << b) if b < 64 - 8
> and the case (1 << b) - 1
> and the case ~((1 << b) - 1)


ohh yeh i remember now.



> It might use a different value than 8 -- icr.
>
> this covers all the corner cases I can think of, which random testing has a
> very small chance of ever hitting


yehyeh this is why the ieee754fp tests have to have special cornercase
handling, zero, inf, nan etc.

(small enough that you'd need every
> person on the planet to all run the test on the order of a billion times
> each to hit the case once).


:)

we need a way to express these, cross language, so that they can be run in
multiple scenarios.

qemu, pia, ISACaller, HDL.

l.



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