Re: [Qemu-devel] [RFC] TCG unit testing

[Rob Landley <rob@landley.net>]

On 09/02/2013 11:07:03 AM, Aurelien Jarno wrote:
> On Fri, Aug 23, 2013 at 12:47:43PM -0700, Richard Henderson wrote:
> > I've been thinking for a while about how to reliably test TCG  
> backends, and
> > maybe how to do regression testing on them.  Having to begin the  
> test from a
> > guest binary, especially considering the vast cross-compilation  
> problem, is
> > pretty much a non-starter.
> 
> Given the regular breakages we have with TCG, it's really a gread  
> idea.
> Usually most of the targets are working correctly so the problem is  
> not
> found immediately.
> 
> > I've been thinking of a truly stripped down target for the purpose,  
> with a
> > special-purpose machine loop and main to go with it.  I.e. avoid  
> vl.c.
> 
> I think we should use as much as possible of the current  
> infrastructure,
> having two different main loops means they are going to be
> desynchronised at some point.
> 
> Ideally it would be nice to have a machine called TCG (maybe with a  
> few
> variants for big/little endian, 32 and 64-bits) which loads TCG "code"
> from a text file and execute it. Then we can imagine zillions of small
> testcases like the GCC ones, and more can be added when a problem is
> discovered and fixed.

Someday, I'd still like to hook Fabrice's old tinycc front end to tcg  
as the code generation backend...

Rob