mini documentation of "info registers" output

Dear list

Here is a little cheat sheet for you to better understand what "info 
registers" shows on qemu's monitor. This infomations are strictly for 
x86

Feel free to correct or send feedbacks about this document

PS: Hetz, please "copy" this document toward Qemu forums.... Thank you 
in advance...

regards

Mulyadi

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Re: mini documentation of "info registers" output

On Friday 01 July 2005 05:33, Mulyadi Santosa wrote:
> Dear list
>
> Here is a little cheat sheet for you to better understand what "info
> registers" shows on qemu's monitor. This infomations are strictly for
> x86

> CCS : Compiled Code Source (?)

Condition Code Source.

> CCD : Compiled Code Destination (?)

Condition Code Source.

> CCO : (?) instruction name

Condition Code Operation

These 3 are used to implement lazy flag evaluation. Most x86 instructions set 
the condition code flags, but only a relatively small subset of instructions 
actually use these flags.

Calculating the flags at every operation would be very slow. Instead qemu just 
remembers the destination, one source operand and the instruction class of a 
flag setting operation, then lazily evaluates the flags as needed.

Paul

documentation of Qemu+openSSI

Hello everybody

here is my first version of openSSI+qemu HOWTO.  I cc'ed this to 
qemu-devel in case anyone might have similar interest to build virtual 
cluster like I did.

Feel free to give commentaries and feedback.

PS: I am so glad that finally I can write it! Fighting laziness is so 
damn hard

regards

Mulyadi

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Re: Re: mini documentation of "info registers" output

Hello Paul...

> > CCD : Compiled Code Destination (?)
>
> Condition Code Source.

Or Condition Code Destination?

> These 3 are used to implement lazy flag evaluation. Most x86
> instructions set the condition code flags, but only a relatively
> small subset of instructions actually use these flags.

hm, i see....BTW, these two lazy flags, CCS and CCD, they are the 
representation of EFLAGS? CMIIW. If yes, can I assume that they have 
same format as EFLAGS?

anyway, it is safe to frequently ignore flags? For example, if MUL 
generate overflow and set Zero Flag, Qemu must be aware of it, right? 
Or we can still safely ignore it?

regards

Mulyadi

Re: mini documentation of "info registers" output

Le samedi, 2 jul 2005, à 06:12 Europe/Paris, Mulyadi Santosa a écrit :

> hm, i see....BTW, these two lazy flags, CCS and CCD, they are the
> representation of EFLAGS?

CCS/CCD = Condition Codes Source/Destination values. Those represent 
part of the state (input and/or result + operation type) used to 
evaluate the EFLAGS, when necessary. Hence the term lazy evaluation of 
condition codes and they aren't in the EFLAGS format.

> anyway, it is safe to frequently ignore flags? For example, if MUL
> generate overflow and set Zero Flag, Qemu must be aware of it, right?
> Or we can still safely ignore it?

Liveness analysis of the EFLAGS bits is performed to determine where 
computation of EFLAGS is really needed.

Bye,
Gwenolé.

Re: documentation of Qemu+openSSI

Mulyadi,

I think it will be a good idea if you put the Howto that you've sent
to here - inside the QEMU forums in the HOWTOs section. That way, you
could always edit your text in the forum and it's the most accessible
way for everyone.

Check it at http://qemu.dad-answers.com/

PS: you could also put the file you sent me in the forum too, as I
don't have SSH right now from where I type this right now. Just don't
put it as a ZIP file please :)

Thanks,
Hetz

On 7/2/05, Mulyadi Santosa <a_mulyadi <at> softhome.net> wrote:
> Hello everybody
> 
> here is my first version of openSSI+qemu HOWTO.  I cc'ed this to
> qemu-devel in case anyone might have similar interest to build virtual
> cluster like I did.
> 
> Feel free to give commentaries and feedback.
> 
> PS: I am so glad that finally I can write it! Fighting laziness is so
> damn hard
> 
> regards
> 

Re: Re: documentation of Qemu+openSSI

Dear Hetz ...

> I think it will be a good idea if you put the Howto that you've sent
> to here - inside the QEMU forums in the HOWTOs section. That way, you
> could always edit your text in the forum and it's the most accessible
> way for everyone.

Ahhh, yes, sorry...I forgot about the Qemu forum...anyway...I already 
submit it there...

Qemu+openSSI
http://qemu.dad-answers.com/viewtopic.php?t=29

Info registers cheat sheet
http://qemu.dad-answers.com/viewtopic.php?t=28

thank you for your help

regards

Mulyadi

qemu exec-all.h

CVSROOT:	/cvsroot/qemu
Module name:	qemu
Branch: 	
Changes by:	Fabrice Bellard <bellard <at> savannah.gnu.org>	05/07/02 13:31:24

Modified files:
	.              : exec-all.h 

Log message:
	correct __builtin_expect definition - increased code gen buffer size for x86

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/qemu/qemu/exec-all.h.diff?tr1=1.31&tr2=1.32&r1=text&r2=text

qemu configure

CVSROOT:	/cvsroot/qemu
Module name:	qemu
Branch: 	
Changes by:	Fabrice Bellard <bellard <at> savannah.gnu.org>	05/07/02 13:32:17

Modified files:
	.              : configure 

Log message:
	Configure check for graphical output (Paul Brook)

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/qemu/qemu/configure.diff?tr1=1.68&tr2=1.69&r1=text&r2=text

qemu block-vmdk.c Changelog

CVSROOT:	/cvsroot/qemu
Module name:	qemu
Branch: 	
Changes by:	Fabrice Bellard <bellard <at> savannah.gnu.org>	05/07/02 14:02:54

Modified files:
	.              : block-vmdk.c Changelog 

Log message:
	VMDK disk image creation (Filip Navara)

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/qemu/qemu/block-vmdk.c.diff?tr1=1.5&tr2=1.6&r1=text&r2=text
http://savannah.gnu.org/cgi-bin/viewcvs/qemu/qemu/Changelog.diff?tr1=1.90&tr2=1.91&r1=text&r2=text