[llvm] [LV] Nest cl::opts under namespace llvm (NFC) (PR #221891)

[Florian Hahn via llvm-commits]

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@@ -51,6 +51,9 @@
 
 namespace llvm {
 
+LLVM_ABI extern cl::opt<unsigned> NumberOfStoresToPredicate;
+LLVM_ABI extern cl::opt<bool> VPlanBuildOuterloopStressTest;
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fhahn wrote:

Yep, but I think it can be moved to `namespace llvm {}` without moving to the header? I am just thinking that pulling this into the header may introduce dependencies, which would be good to avoid unless necessary.

https://github.com/llvm/llvm-project/pull/221891