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

[Robert Imschweiler via llvm-commits]

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@@ -0,0 +1,55 @@
+; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=amdgcn -mcpu=gfx942 -O0 -stop-after=amdgpu-isel -o - %s | FileCheck --check-prefix=SelDAG %s
+; RUN: llc -global-isel -mtriple=amdgcn -mcpu=gfx942 -stop-after=legalizer -o - %s | FileCheck --check-prefix=GlobalISel %s
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ro-i wrote:

Ok, done. But then I only get an empty block (so `%bb.0: s_endpgm`). At least for GlobalIsel (no matter if `-O0` or not) and also for SelDAG if I remove the `-O0`.

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