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Operating System Specific Discussions => Amiga OS => Amiga OS -- Development => Topic started by: Karlos on November 11, 2003, 12:35:50 AM

Title: Quick assembler question
Post by: Karlos on November 11, 2003, 12:35:50 AM

Hi all,

Does anybody know if the 68040 single/double precision rounded FPU instructions such as fsmul, fsadd etc. work on 68060?

Title: Re: Quick assembler question
Post by: iamaboringperson on November 11, 2003, 06:44:41 AM

From memory, I think there were a couple of multiply instructions left out.

Obviously the 68060 should fix it all up.

Does that help?



Waddya mean NO??    

Title: Re: Quick assembler question
Post by: Steady on November 11, 2003, 09:50:28 AM

Perhaps obvious, but maybe the resources here (http://e-www.motorola.com/webapp/sps/library/documentationlist.jsp?rootNodeId=01&nodeId=018rH3YTLC4622&Device=MC68060&DocTypeKey=10Ksfwlk&Results=25) might help.

P.S. How do I embed? I thought the anchor tag was enough. Extract website from the info above until I get the embedding right.

[EDIT: Fixed URL]

Title: Re: Quick assembler question
Post by: GadgetMaster on November 11, 2003, 10:06:02 AM

Quote

Steady wrote:

P.S. How do I embed? I thought the anchor tag was enough. Extract website from the info above until I get the embedding right.

http://e-www.motorola.com/webapp/sps/library/documentationlist.jsp?rootNodeId=01&nodeId=018rH3YTLC4622&Device=MC68060&DocTypeKey=10Ksfwlk&Results=25 (http://e-www.motorola.com/webapp/sps/library/documentationlist.jsp?rootNodeId=01&nodeId=018rH3YTLC4622&Device=MC68060&DocTypeKey=10Ksfwlk&Results=25)

There! You just click the URL button and add your link. :-)

You can even keep it short
Like This (http://e-www.motorola.com/webapp/sps/library/documentationlist.jsp?rootNodeId=01&nodeId=018rH3YTLC4622&Device=MC68060&DocTypeKey=10Ksfwlk&Results=25)

Title: Re: Quick assembler question
Post by: Steady on November 11, 2003, 02:22:20 PM

DOH!

Thanks GadgetMaster. I suffer severely from domestic blindness (can't see something that is directly in front of you.

I fixed my link now  :-D

Title: Re: Quick assembler question
Post by: Karlos on November 11, 2003, 02:50:56 PM

Thanks chaps ;-)

Title: Re: Quick assembler question
Post by: PiR on November 12, 2003, 11:10:45 AM

Hi Karlos

Just checked it last night in 68060 UM. They're hardware implemented. However what do these really do is rounding the result to single/double, regardless on the current FPU control setting, AND NOT making calculations in single/double. Calculations are always done in extended precision (or even more).

I've found SGLMUL, which makes calculations in single precision, but this is 6888x only and only emulated both on 68040 and 68060.

You can find all this in the manuals  from that link to motorola site.

Good luck

Title: Re: Quick assembler question
Post by: Karlos on November 16, 2003, 03:30:38 AM

@PiR

That's OK, its just that I had some code using those rounded instructions. I have rewritten it anyway so it isn't a concern now.

Anyway I got another RTFM for you all :-)

Can anybody confirm for me if repetetive indirect calls to an address such as

jsr (a0)

on the 68060 are folded out by the branch prediction unit or not? I don't have time to trawl through the 68060 User Manual just now but wondered if anybody happens to know...

Thanks :-)