[llvm] [GenericCycle] Add a Cache for getExitBlocks in GenericCycle (PR #112290)

[Sameer Sahasrabuddhe via llvm-commits]

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@@ -124,7 +141,12 @@ template <typename ContextT> class GenericCycle {
   bool contains(const GenericCycle *C) const;
 
   const GenericCycle *getParentCycle() const { return ParentCycle; }
-  GenericCycle *getParentCycle() { return ParentCycle; }
+
+  GenericCycle *getParentCycle() {
+    clearCache();
+    return ParentCycle;
+  }
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ssahasra wrote:

Yeah, clearly there is no change in state here and we don't need to clear the cache. At least this one is obvious enough. We could later revisit other non-const functions too, maybe as a future enhancement.

https://github.com/llvm/llvm-project/pull/112290