optimizer: code quality and performance improvements to post-opt analysis (#51211)
This PR is composed of a set of fixes and improvements to
`ipo_dataflow_analysis!`.
I will rebase this once we merge #51185 and #51188, so still WIP, but
let's see benchmark.
@nanosoldier `runbenchmarks("inference", vs=":master")`
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Co-authored-by: Keno Fischer <keno@juliahub.com>