[llvm] Missing opt with ctlz and shifts of power of 2 constants (#41333) (PR #74175)

[Yingwei Zheng via llvm-commits]

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@@ -514,6 +514,8 @@ static Instruction *foldCttzCtlz(IntrinsicInst &II, InstCombinerImpl &IC) {
     return IC.replaceInstUsesWith(II, ConstantInt::getNullValue(II.getType()));
   }
 
+  ConstantInt *CInt;
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dtcxzyw wrote:

Seems like it cannot handle constant splat vectors.

https://github.com/llvm/llvm-project/pull/74175