Follow-up to https://reviews.llvm.org/D97810.
Sorry, I forgot that codegen is still legacy PM, so -debug-pass=Structure does give the correct output. Then users need to specify both -debug-pass-manager and -debug-pass=x to get the pass information. Hmm, not a big deal but seems hassles. Maybe we should bridge -debug-pass=Structure to -debug-pass-manager ? Or actually, this could be a feature where users can specify either pipeline they want the pass information for. WDYT?