[AutoTVM][Autoscheduler] Default build funcs inherit PassContext

[AndrewZhaoLuo]

See #11618 for old discussion

These funcs used building during the tuning process now inherit PassContext so we can inject things like pass instrumentation into the build process during tuning.

Note, due to the fact subprocesses are used for building by default, we can't naively do something like

with PassContext(...):
   tune()

since new processes will not inherit the parents context.

But what does allow us to do is wrap the existing build functions with new PassContexts and call those instead making it a little more extensible.

[areusch]

@AndrewZhaoLuo ping me when ready for another look

[AndrewZhaoLuo]

Synced offline with @areusch, and created #11656 to track this unintuitive behavior.

[areusch]

i'm good with this, but can you add a unit test to verify check_gpu is applied?

[AndrewZhaoLuo]

Added a test, PTAL @areusch

It's a bit of a doozy though since I had to patch a lot of things

[areusch]

want to check the pass also succeeded? i think if one of those asserts fail we just get measure error here

[AndrewZhaoLuo]

assertions will fail the test so I think it's safe -- we just want to make sure proper passes are run

We don't want to check for success in tuning since the tuning process on GPU is actually flaky (see test_tuning_gpu()) above.

[areusch]

ah ok--maybe the runner is where exceptions don't fail the test. good enough, if you've proven locally an exception causes the test to fail.