[llvm] [DAGCombine] `visitANY_EXTEND` - fold `(aext (freeze (load x)))` -> `(aext (truncate (freeze (extload x))))` (PR #218454)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,60 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
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RKSimon wrote:

this test file might be redundant due to the changes to existing similar tests?

https://github.com/llvm/llvm-project/pull/218454