[llvm] [DebugInfo][RemoveDIs] Use autoupgrader to convert old debug-info (PR #143452)

[via llvm-commits]

github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {undef deprecator}-->


:warning: undef deprecator found issues in your code. :warning:

<details>
<summary>
You can test this locally with the following command:
</summary>

``````````bash
git diff -U0 --pickaxe-regex -S '([^a-zA-Z0-9#_-]undef[^a-zA-Z0-9_-]|UndefValue::get)' 'HEAD~1' HEAD llvm/test/Verifier/RemoveDI/invalid-dbg-declare-operands.ll llvm/test/Verifier/dbg-declare-invalid-debug-loc.ll llvm/lib/AsmParser/LLParser.cpp llvm/lib/IR/AsmWriter.cpp llvm/lib/IR/AutoUpgrade.cpp llvm/lib/IR/BasicBlock.cpp llvm/lib/IR/Verifier.cpp llvm/test/Assembler/drop-debug-info-nonzero-alloca.ll llvm/test/DebugInfo/Generic/assignment-tracking/parse-and-verify/verify.ll llvm/test/DebugInfo/Generic/sroa-extract-bits.ll llvm/test/Transforms/IROutliner/outlining-debug-statements.ll llvm/test/Transforms/ObjCARC/code-motion.ll llvm/test/Verifier/diexpression-entry-value-llvm-ir.ll llvm/test/Verifier/llvm.dbg.declare-address.ll llvm/test/Verifier/llvm.dbg.declare-expression.ll llvm/test/Verifier/llvm.dbg.declare-variable.ll llvm/test/Verifier/llvm.dbg.intrinsic-dbg-attachment.ll llvm/test/Verifier/llvm.dbg.value-expression.ll llvm/test/Verifier/llvm.dbg.value-value.ll llvm/test/Verifier/llvm.dbg.value-variable.ll llvm/unittests/IR/DebugInfoTest.cpp
``````````

</details>


The following files introduce new uses of undef:
 - llvm/test/Assembler/drop-debug-info-nonzero-alloca.ll
 - llvm/test/Verifier/dbg-declare-invalid-debug-loc.ll

[Undef](https://llvm.org/docs/LangRef.html#undefined-values) is now deprecated and should only be used in the rare cases where no replacement is possible. For example, a load of uninitialized memory yields `undef`. You should use `poison` values for placeholders instead.

In tests, avoid using `undef` and having tests that trigger undefined behavior. If you need an operand with some unimportant value, you can add a new argument to the function and use that instead.

For example, this is considered a bad practice:
```llvm
define void @fn() {
  ...
  br i1 undef, ...
}
```

Please use the following instead:
```llvm
define void @fn(i1 %cond) {
  ...
  br i1 %cond, ...
}
```

Please refer to the [Undefined Behavior Manual](https://llvm.org/docs/UndefinedBehavior.html) for more information.



https://github.com/llvm/llvm-project/pull/143452