[llvm] [LV] Adjust exit recipe detection to run on early vplan (PR #183318)

[Florian Hahn via llvm-commits]

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@@ -471,10 +471,9 @@ unsigned vputils::getVFScaleFactor(VPRecipeBase *R) {
   return 1;
 }
 
-std::optional<VPValue *>
-vputils::getRecipesForUncountableExit(VPlan &Plan,
-                                      SmallVectorImpl<VPRecipeBase *> &Recipes,
-                                      SmallVectorImpl<VPRecipeBase *> &GEPs) {
+std::optional<VPValue *> vputils::getRecipesForUncountableExit(
+    VPlan &Plan, SmallVectorImpl<VPInstruction *> &Recipes,
+    SmallVectorImpl<VPInstruction *> &GEPs, VPBasicBlock *LatchVPBB) {
   // Given a VPlan like the following (just including the recipes contributing
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fhahn wrote:

Probably worth updating now that it operates on plain CFG loop
```suggestion
  // Given a plain CFG VPlan loop with countable latch exiting block \p LatchVPBB ....
```

https://github.com/llvm/llvm-project/pull/183318