[llvm] [VPlan] Simplify PredPHI LiveIn -> LiveIn (PR #142271)

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,150 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 5
+; RUN: opt -passes=loop-vectorize -S %s | FileCheck %s
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fhahn wrote:

Can this test be made independent of the X86 target, by providing something like `-force-vector-width=2`?

https://github.com/llvm/llvm-project/pull/142271