[PATCH] D94355: [Passes] Add relative lookup table converter pass

[Arthur Eubanks via Phabricator via llvm-commits]

aeubanks added inline comments.


================
Comment at: llvm/test/Other/opt-O3-pipeline-enable-matrix.ll:322-323
 ; CHECK-NEXT:       Simplify the CFG
+; CHECK-NEXT:     Relative Lookup Table Converter
+; CHECK-NEXT:     FunctionPass Manager
 ; CHECK-NEXT:       Annotation Remarks
----------------
rnk wrote:
> Putting a ModulePass in the middle of the CodeGen pass pipeline creates a "pass barrier": now instead of applying every pass to each function in turn, the old pass manager will stop, run this whole-module pass, and then run subseqeunt passes in the next function pass manager on each function in turn. This isn't ideal. @aeubanks, can you follow-up to make sure this is addressed?
> 
> We had the same issues with the SymbolRewriter pass, which if you grep for "Rewrite Symbols" you can see has the same issue. I remember writing a patch to fix it, but I guess I never landed it.
I see "Rewrite Symbols" in the codegen pipeline and yeah it's splitting the function pass manager.

For this patch, can we just not add the pass to the legacy PM pipeline? It's deprecated and the new PM is already the default for the optimization pipeline.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D94355/new/

https://reviews.llvm.org/D94355