[PATCH] D56242: Elevate instructions across if-else blocks for better constant propagation

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

Please include a few simpler testcases, so it's more obvious what the pass actually does.  As far as I can tell, this is similar to InstCombiner::foldOpIntoPhi, but it's a lot more aggressive?

It looks like this increases codesize, in general; do we need some limit to prevent codesize from exploding in general?  Should that limit depend on optsize?



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Comment at: test/Transforms/Elevate/elevate-if-else.ll:1
+; RUN: opt < %s -O3 -elevate -S | FileCheck %s
+
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Please don't use -O3 in opt testcases.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D56242/new/

https://reviews.llvm.org/D56242