[llvm] [LV] Move check if any vector insts will be generated to VPlan. (PR #96622)

[Florian Hahn via llvm-commits]

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@@ -1,4 +1,4 @@
-; RUN: opt < %s -passes=loop-vectorize -S | FileCheck %s
+; RUN: opt < %s -passes=loop-vectorize -force-vector-width=4 -S | FileCheck %s
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fhahn wrote:

I think it makes sense, as there won't be any code at all generated for dead instructions that have been cleaned up by DCE

https://github.com/llvm/llvm-project/pull/96622