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.