Running the compat testsuite in "non-mirror" mode

[Eric Botcazou]

Hello Janis,

I'd like to automatically run the compat testsuite in "non-mirror" mode on the 
SPARC, to assert internal consistency for vector calling conventions, in 
addition to the regular "mirror" mode.

What is the best approach to achieve that?  Can I duplicate compat.exp and 
override ALT_CC_UNDER_TEST and COMPAT_OPTIONS in a sparc-compat.exp driver?  
Would it be feasible to invoke compat.exp from another driver, for example 
located in the gcc.target/sparc directory?

Thanks in advance.

-- 
Eric Botcazou