[llvm] [AMDGPU] Generate waterfall for calls with SGPR(inreg) argument (PR #146997)

[Matt Arsenault via llvm-commits]

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@@ -1,22 +1,452 @@
-; RUN: not llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -verify-machineinstrs=0 -filetype=null %s 2>&1 | FileCheck -enable-var-scope %s
-
-; CHECK: illegal VGPR to SGPR copy
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -verify-machineinstrs < %s | FileCheck -enable-var-scope %s
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arsenm wrote:

```suggestion
; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 < %s | FileCheck -enable-var-scope %s
```

https://github.com/llvm/llvm-project/pull/146997