[llvm] [Attributor]: Fix Potential bug when handling PHI in AAPointerInfo (PR #97321)

[Shilei Tian via llvm-commits]

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@@ -214,7 +214,7 @@ ChangeStatus clampStateAndIndicateChange<DerefState>(DerefState &S,
 static bool mayBeInCycle(const CycleInfo *CI, const Instruction *I,
                          bool HeaderOnly, Cycle **CPtr = nullptr) {
   if (!CI)
-    return true;
+    return false;
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shiltian wrote:

I thought we need to assume the worst if certain info is not available?

https://github.com/llvm/llvm-project/pull/97321