[llvm] [LiveDebugVariables] Add tests for stale SlotIndexes (PR #225375)

[Jay Foad via llvm-commits]

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@@ -0,0 +1,70 @@
+; RUN: llc -mtriple=aarch64-unknown-linux-gnu -O2 -stop-after=virtregrewriter %s -o - | FileCheck %s
+
+; LiveDebugVariables records SlotIndexes during register allocation and uses
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jayfoad wrote:

Combined a bit so there is only one test file for each target.

https://github.com/llvm/llvm-project/pull/225375