[llvm] [CodeGen] Guard copy propagation in machine CSE against undefs (PR #97413)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,22 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -mtriple=amdgcn -run-pass=machine-cse -verify-machineinstrs -o - %s | FileCheck %s
+
+# Test to ensure that this does not crash on undefs
+---
+name: machine-cse-copyprop
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arsenm wrote:

Name should indicate it's testing the undef case 

https://github.com/llvm/llvm-project/pull/97413