[llvm] [msan][NFCI] Add tests for NEON saturating extract and narrow (PR #125140)

[Florian Mayer via llvm-commits]

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@@ -0,0 +1,750 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt < %s -passes=msan -S | FileCheck %s
+;
+; Forked from llvm/test/CodeGen/AArch64/qshrn.ll
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fmayer wrote:

Add a comment that they are currently incorrectly handled?

https://github.com/llvm/llvm-project/pull/125140