[llvm] [VPlan] Fix LastActiveLane assertion on scalar VF (PR #167897)

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,53 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 6
+; RUN: opt -p loop-vectorize -prefer-predicate-over-epilogue=predicate-else-scalar-epilogue -force-vector-width=1 -force-vector-interleave=2 -S %s | FileCheck %s
+
+define i64 @live_out_scalar_vf(i64 %n) {
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fhahn wrote:

if possible, might be good to add this to `llvm/test/Transforms/LoopVectorize/tail-folding-vectorization-factor-1.ll`, which already contains a set of test cases for interleaving only with tail-folding.

https://github.com/llvm/llvm-project/pull/167897