[llvm] [DebugInfo] Fix faulty DIExpression::appendToStack assert (PR #85255)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -0,0 +1,49 @@
+; RUN: opt -passes=instcombine -S < %s | FileCheck %s
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OCHyams wrote:

+1, seems reasonable to explore putting this in a unittest instead

https://github.com/llvm/llvm-project/pull/85255