[llvm] [AMDGPU] Cost of i8 vector insert/extract is free in some cases (PR #194991)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,150 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
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arsenm wrote:

Using old update_llc_test_checks version 

https://github.com/llvm/llvm-project/pull/194991