[llvm] [AMDGPU][True16][CodeGen] sext i16 inreg in true16 mode (PR #144024)

[Joe Nash via llvm-commits]

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@@ -1,131 +1,411 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
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Sisyph wrote:

I believe no tests in this file cover the code changes in this patch? If so, please revert the auto-generation change and gfx11 coverage. If you want it, please open a separate patch. 

https://github.com/llvm/llvm-project/pull/144024