[llvm] [PassBuilder] Add a pass to LTO postlink step (PR #124053)

[Paul Kirth via llvm-commits]

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@@ -1926,6 +1926,8 @@ PassBuilder::buildLTODefaultPipeline(OptimizationLevel Level,
   // Remove unused arguments from functions.
   MPM.addPass(DeadArgumentEliminationPass());
 
+  MPM.addPass(RelLookupTableConverterPass());
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ilovepi wrote:

Well, I was thinking that wanting PIC friendly lookup tables isn't necessarily something tied to the optimization level. For instance, I'd suppose if you care about PIC friendliness, you'd want it on even at low opt levels. That's also something easy to revisit, though, so its probably fine to start here and revisit as needed.

https://github.com/llvm/llvm-project/pull/124053