[llvm] [CodeGen][AMDGPU] Replace isBasicBlockPrologue with a MachineInstr::BBProlog flag (PR #225433)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,43 @@
+# RUN: not --crash llc -mtriple=amdgpu9.00 -verify-machineinstrs -run-pass=none -filetype=null %s 2>&1 | FileCheck %s
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arsenm wrote:

```suggestion
# RUN: not --crash llc -mtriple=amdgpu9.00 -run-pass=none -filetype=null %s 2>&1 | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/225433