[llvm] [InitUndef] Enable the InitUndef pass on non-AMDGPU targets (PR #108353)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,44 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -mtriple=aarch64-- -run-pass=init-undef -o - %s | FileCheck %s
+
+--- |
+  define dso_local i32 @test_stxp_undef(ptr %p, i64 %x) #0 {
+    %res = call i32 @llvm.aarch64.stxp(i64 undef, i64 %x, ptr %p)
+    ret i32 %res
+  }
+
+...
+---
+name:            test_stxp_undef
+alignment:       4
+tracksRegLiveness: true
+registers:
+  - { id: 0, class: gpr64common }
+  - { id: 1, class: gpr64 }
+  - { id: 2, class: gpr32 }
+  - { id: 3, class: gpr64 }
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arsenm wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/108353