PCode test improvements

[antoniovazquezblanco]

I've recently started playing with processor support. I discovered the PCode test suite and tryed to use it. After some code reading I had some ideas that may help improve user experience around the test suite.

I've opened a pull request (#6549) to improve (by my opinionated criteria) the python code that preprocesses the test files. The PR should make this code easyer to maintain and it helped me to understand what was this preprocessor doing.

In a summarized way, it defines test functions and adds them to a couple of tables that are later on used to generate a main file that calls all the different test functions.

I've been thinking for a while on how to get rid of this preprocessor. In my opinion, although it works, it is not the best way to carry out this task. I was thinking on how to do this and I landed a way to do it with macros and sections only from C code. I've uploaded a test implementation of the idea in https://github.com/antoniovazquezblanco/func-autoreg-test.

I was wondering what is your opinion on trying to implement this idea in the PCode test suite to get rid of the python code preprocessor. Do you see any pros or cons in favour or against the idea?

Thanks

[antoniovazquezblanco]

Friendly ping to bring @GhidorahRex and @ryanmkurtz because they have interacted in the original PR. Any pointers from the team? Do you like the idea or do you find it convoluted?

Thanks!