llvm-project

b8930cd1 - Add a pass to collect dropped variable statistics (#102233)

Add a pass to collect dropped variable statistics (#102233) This patch is inspired by @Snowy1803 excellent work in swift and the patch: https://github.com/swiftlang/swift/pull/73334/files Add an instrumentation pass to llvm to collect dropped debug information variable statistics for every Function-level and Module-level IR pass. This patch creates adds the class DroppedVariableStats which iterates over every DbgRecord in a function or module before and after an optimization pass and counts the number of variables who's debug information has been dropped due to that pass, then prints that output to stdout in a csv format. I ran this patch on optdriver.cpp can see: Pass Name, Dropped Variables 'InstCombinePass', 1 'SimplifyCFGPass', 6 'JumpThreadingPass', 25