Re: [Qemu-devel] [PATCH] ppc: Convert op_440_dlmzb to TCG

[Laurent Desnogues]

On Sun, Nov 30, 2008 at 7:03 PM, Andreas Färber <address@hidden> wrote:
>
> So, if I encounter a dyngen op that calls a helper, then in general I should
> convert it to TCG code calling the helper?

I guess it depends, but in most cases probably.  If an instruction is
not used often and its implementation in the old helper is rather
long or uses branches (if/else, loops), you should keep it as a
helper.

> My next problem is op_440_tlbre, which does call a helper, but with a PARAM1
> argument. Any hint how to translate that?

I am not familiar at all with the old generator, so take what I say with
a grain of salt :-)

PARAM1 probably was a parameter passed at runtime.  Now with
the way helper calls are generated, you explicitly pass parameters.
Your best bet is to look at how Aurélien reimplemented dlmzb or
any other complex helpers since he started the conversion to TCG.


Laurent