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

[Yingwei Zheng via llvm-commits]

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@@ -0,0 +1,36 @@
+; RUN: opt -passes=instcombine -S < %s | FileCheck %s
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dtcxzyw wrote:

1. Please regenerate this test with `llvm/utils/update_test_checks.py`.
2. Please add some negative tests.


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