[PATCH] D108978: [NFC] [LoopDeletion] Move ICmpInst handling to getValueOnFirstIteration()

Thu Sep 2 09:25:09 PDT 2021

reames accepted this revision.
reames added a comment.
This revision is now accepted and ready to land.

LGTM

Though, I don't believe this is NFC.  It would be stronger in the case such as:
%a = icmp ...
%b = icmp ...
%c = or i1 %a, %b
%d = icmp eq i1 %c, 1
br i1 %d....

This is non-canonical IR so this should be a rare pattern in practice, but I don't think this is actually NFC.

================
Comment at: llvm/lib/Transforms/Scalar/LoopDeletion.cpp:329
+      auto *ICmp = dyn_cast<ICmpInst>(Cond);
+      if (!ICmp || !ICmp->getType()->isIntegerTy()) {
         MarkAllSuccessorsLive(BB);
----------------
As a follow up, it looks like this test is now redundant for the new code structure.  Only part I'm unsure of is the integer test, but I also don't understand why that's there at all.  

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D108978/new/

https://reviews.llvm.org/D108978