[llvm] [AMDGPU] SelDAG: fix lowering of undefined workitem intrinsics (PR #126058)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,36 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=amdgcn -mcpu=gfx942 -O0 --global-isel=false -o - %s | FileCheck %s
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arsenm wrote:

Does this really need -O0? Is there an existing test this can merge with? The -undefined-attr is misleading because no attribute is involved here

Should test with and without globalisel 

https://github.com/llvm/llvm-project/pull/126058