[llvm] [SCEV] Use SCEVUse for ValuesAtScope (NFC). (PR #207062)

[Ramkumar Ramachandra via llvm-commits]

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@@ -2372,7 +2385,14 @@ class ScalarEvolution {
   void forgetMemoizedResults(ArrayRef<SCEVUse> SCEVs);
 
   /// Helper for forgetMemoizedResults.
-  void forgetMemoizedResultsImpl(const SCEV *S);
+  void forgetMemoizedResultsImpl(SCEVUse S);
+
+  /// If \p U carries use-specific flags, record it as a flagged use of the
+  /// underlying canonical SCEV.
+  void registerFlaggedUse(SCEVUse U) {
+    if (U.hasUseFlags())
+      FlaggedUses[U.getPointer()].insert(U);
+  }
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artagnon wrote:

Slightly confused about why we need to register FlaggedUses? Wouldn't the right solution be to use SCEVUse uniformly everywhere?

https://github.com/llvm/llvm-project/pull/207062