[llvm] [MIR] Replace bespoke DIExpression parser (PR #96827)

[Scott Linder via llvm-commits]

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@@ -0,0 +1,152 @@
+# RUN: not llc -run-pass none -o - %s 2>&1 | FileCheck %s
+# Note: generated via:
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slinder1 wrote:

Yes, I wanted to ensure the diagnostic retains essentially the same character before and after the change.

The diff between the first and second commit in the PR shows that the error message changes (with both versions being equivalent) but the line+column in the diagnostic is identical.

I didn't trim the test as I couldn't find a great reference for what extent to do so (e.g. https://groups.google.com/g/llvm-dev/c/6heEIwca_t0 doesn't seem to have a resolution wrt. the metadata itself), and testing "real world" input IR seemed the least likely to mistakenly verify something that isn't true in practice. I seem to run into this every time I write a test, and still haven't come up with a great approach.

https://github.com/llvm/llvm-project/pull/96827