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Re: [Qemu-devel] mini documentation of "info registers" output


From: Paul Brook
Subject: Re: [Qemu-devel] mini documentation of "info registers" output
Date: Fri, 1 Jul 2005 13:17:43 +0100
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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






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