[llvm] [ValueTracking] Handle recursive select/PHI in ComputeKnownBits (PR #114689)

[via llvm-commits]

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@@ -580,6 +580,43 @@ static bool cmpExcludesZero(CmpInst::Predicate Pred, const Value *RHS) {
   return true;
 }
 
+static void breakSelfRecursivePHI(const Use *U, const PHINode *PHI,
+                                  Value *&ValOut, Instruction *&CtxIOut,
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goldsteinn wrote:

Although this seems aligned with how we do output variables for other helpers.

https://github.com/llvm/llvm-project/pull/114689