Re: [hatari-devel] FPU update

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Am 19.01.2017 um 08:36 schrieb Toni Wilen <twilen@xxxxxxxxxx>:

>>> Wouldn't the easiest way be to check this on actual hardware?
>> Absolutely. But i don't have any 68k hardware. So if anyone wants to
>> test this, that would be very helpful. Some changes to SoftFloat's
>> core functions would be required. I don't want to touch them without
>> some reliable information about how this should work.
> I have already volunteered to do that. (68030 + 68882) I only need
> (tiny) test source code.

I'm not able to write an assembly program, but i can provide some pseudo code:

1. set FPCR to 80-bit rounding precision
	0x0000 --> FPCR

2. load register with denormal number:
	0x00000000 0x10000000 0x00000000 --> FPx

3. load another register with integer 2
	2 --> FPy

4. do following loop:
	for (int i = 0; i < 6; i++)
		FPx = FMUL(FPx, FPy);
		print content of FPx in hexadecimal format

That will answer the question.

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