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

[Felipe de Azevedo Piovezan via llvm-commits]

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

An _instcombine_ test in order to test a change to DIEExpression::append operation feels like the wrong granularity. Not to mention this test could start failing for other reasons in the future.

Suggestion:  could you have a look at unittests and check if you can build a DIEExpression manually there, and then call `appendToStack`?

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