[llvm] [LV] Add initial legality checks for ee loops with stores (PR #145663)

[Florian Hahn via llvm-commits]

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@@ -515,20 +523,87 @@ class LoopVectorizationLegality {
   /// Returns true if this is an early exit loop that can be vectorized.
   /// Currently, a loop with an uncountable early exit is considered
   /// vectorizable if:
-  ///   1. There are no writes to memory in the loop.
+  ///   1. Writes to memory do not form a dependence with any load used as
+  ///      part of the uncounted exit condition.
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fhahn wrote:

```suggestion
  ///      part of the uncountable exit condition.
```

https://github.com/llvm/llvm-project/pull/145663