[PATCH] D97219: [LSR] Unify scheduling of existing and inserted addrecs

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev added inline comments.


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Comment at: llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp:5574
+    // First, filter out anything not an obvious addrec
+    if (!SE.isSCEVable(PN.getType()) || !isa<SCEVAddRecExpr>(SE.getSCEV(&PN)))
+      continue;
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Because of simplifications, `isa<SCEVAddRecExpr>(SE.getSCEV(&PN))` is potentially more expensive than everything you are going to make here. If it's not a legality check, I think it should be removed.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D97219/new/

https://reviews.llvm.org/D97219