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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 |
User-agent: |
KMail/1.7.2 |
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