[clang] [llvm] [AMDGPU] Introduce asyncmark/wait intrinsics (PR #173259)

[Matt Arsenault via cfe-commits]

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@@ -0,0 +1,898 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -march=amdgcn -mcpu=gfx900  < %s | FileCheck %s -check-prefixes=GFX900
+; RUN: llc -march=amdgcn -mcpu=gfx942  < %s | FileCheck %s -check-prefixes=GFX942
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arsenm wrote:

```suggestion
; RUN: llc -march=amdgcn -mcpu=gfx900 < %s | FileCheck %s -check-prefixes=GFX900
; RUN: llc -march=amdgcn -mcpu=gfx942 < %s | FileCheck %s -check-prefixes=GFX942
```

https://github.com/llvm/llvm-project/pull/173259