[llvm] [VPlan] Move splitAt test to unit test. NFC (PR #164636)

[Florian Hahn via llvm-commits]

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@@ -239,110 +239,6 @@ exit:
   ret i32 %res
 }
 
-; To sink the replicate region containing %rem, we need to split the block
-; containing %conv at the end, because %conv is the last recipe in the block.
-define void @sink_replicate_region_4_requires_split_at_end_of_block(i32 %x, ptr %ptr, ptr noalias %dst) optsize {
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fhahn wrote:

Can/should we keep the test in addition with an explicit predicate, to keep testing the merge/sink logic as-is at the moment?

https://github.com/llvm/llvm-project/pull/164636