[llvm] [VPlan][PseudoProbe] Fix `pseudoprobe` duplication when `VF=1` (PR #185238)

[David Sherwood via llvm-commits]

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@@ -25,15 +56,44 @@ for.end:                                          ; preds = %for.body
   ret i32 0
 }
 
+define void @test2() {
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david-arm wrote:

What is this testing that's different to `test1`? The CHECK lines seem to be the same at least.

https://github.com/llvm/llvm-project/pull/185238