[llvm] [TailDup][MachineSSAUpdater] Let RewriteUse insert a COPY when needed (PR #95553)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,198 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -verify-machineinstrs -mtriple aarch64-none-linux-gnu -run-pass early-tailduplication -o - %s | FileCheck %s
+
+# These tests used to hit verification failure due to register class
+# mismatches after tail dupilication (and the SSA form updates).
+
+# In test1 we have a simple case when the COPY:s already are duplicated, but
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arsenm wrote:

```suggestion
# In test1 we have a simple case when the COPYs already are duplicated, but
```

https://github.com/llvm/llvm-project/pull/95553