This is a refactor, which should (in theory) not change the behavior of
the compiler. But since this is a pretty large change, there is a chance
there will be some regressions. For that reason, the previous commits
added a bunch of tests to make sure most error messages will not be
changed due to this refactor.
This is just one optimizer pass that's easy to test for. There are
others, but I'm ignoring them for now.
The one other that would be reasonable to test is when starting a
goroutine with -gc=none, but I'm leaving that one for another time.
Match the error messages in testdata/errors/*.go like LLVM FileCheck,
which includes regular expressions.
I believe this is much more flexible, and LLVM uses it in nearly all of
their tests so it must work quite well for compilers.
This is needed for some improvements I'm going to make next.
This commit also refactors error handling slightly to make it more
easily testable, this should hopefully not result in any actual changes
in behavior.
Ayke van Laethem