[PATCH] D132571: [RLEV] Pick a correct insert point when incoming instruction is itself a phi node

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/Transforms/Utils/LoopUtils.cpp:1400
+          (isa<PHINode>(Inst) || isa<LandingPadInst>(Inst)) ?
+          &*Inst->getParent()->getFirstInsertionPt() : Inst;
+        RewritePhiSet.emplace_back(PN, i, ExitValue, InsertPt, HighCost);
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Any reason we don't just use `PN->getIncomingBlock(i)->getTerminator()` as the insertion point? That seems like a more obvious place to materialize an edge value.


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Comment at: llvm/test/Transforms/IndVarSimplify/rewrite-loop-exit-value.ll:188
+  %inc137.lcssa = phi i32 [ %inc137, %for.body ]
+  %conv = trunc i32 %inc137.lcssa to i16
+  ret void
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Can you please return the value from the function? The problem is a bit hard to understand if the RLEV results gets optimized away.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D132571/new/

https://reviews.llvm.org/D132571