[llvm] [LV] Provide utility routine to find uncounted exit recipes (PR #152530)

[Graham Hunter via llvm-commits]

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@@ -148,6 +148,8 @@ class LLVM_ABI_FOR_TEST VPValue {
     return Current != user_end();
   }
 
+  bool hasOneUse() const { return getNumUsers() == 1; }
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huntergr-arm wrote:

_Uses_ are not directly modeled in VPlan, afaict.

Instead, a User may be recorded multiple times for a given VPValue. See the function directly above this, `hasMoreThanOneUniqueUser`, which looks through the list of Users seeing if there's one that's different from the first.

https://github.com/llvm/llvm-project/pull/152530