[llvm] [VPlan] Add VPlan-based addMinIterCheck, replace ILV for non-epilogue. (PR #153643)

[via llvm-commits]

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@@ -2414,8 +2388,8 @@ void InnerLoopVectorizer::createVectorLoopSkeleton(StringRef Prefix) {
                  LI, nullptr, Twine(Prefix) + "scalar.ph");
   // NOTE: The Plan's scalar preheader VPBB isn't replaced with a VPIRBasicBlock
   // wrapping LoopScalarPreHeader here at the moment, because the Plan's scalar
-  // preheader may be unreachable at this point. Instead it is replaced in
-  // createVectorizedLoopSkeleton.
+  // preheader may be unreachable at this point and SCEV expansion may add to it
+  // later.
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ayalz wrote:

will this replacement still take place later?

https://github.com/llvm/llvm-project/pull/153643