> Any high-level benchmarks (i.e. other than pybench and similar programs) impacted by this?

Sorry, I don't have any data. Currently I'm not able to run large benchmarks. I would be surprised if this increases the performance of a macrobenchmark even by 1%. But this change is a step in the direction of getting rid from the peephole optimizer.

> Will this negatively impact code coverage reporting or code tracing (by optimizing across basic blocks)?

I can't imagine the case. The compiler doesn't generate separate line numbers neither for JUMP instructions, nor for auxilary stack manipulating instructions in chained comparison, nor for UNARY_NOT. And these are the only things that are changed. Line number marks are left the same in optimized code, and they points to the same instructions. I think that coverage tools and debugger are not affected.