[llvm] [DebugInfo] Helper method for finding the deepest inlining location (PR #161696)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -2600,14 +2600,23 @@ class DILocation : public MDNode {
   StringRef getDirectory() const { return getScope()->getDirectory(); }
   std::optional<StringRef> getSource() const { return getScope()->getSource(); }
 
+  /// Get the location where this is inlined
+  ///
+  /// Walk through \a getInlinedAt() and return the \a DILocation where this is
+  /// inlined.
+  const DILocation *getInlinedAtLocation() const {
+    const DILocation *Current = this, *Next = nullptr;
+    while (Next = Current->getInlinedAt())
+      Current = Next;
+    return Current;
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OCHyams wrote:

```suggestion
    const DILocation *Current = this
    while (const DILocation *Next = Current->getInlinedAt())
      Current = Next;
    return Current;
```
nit - I think this is a bit neater, what do you think? (and as a side note I would personally avoid multiple variable declarations on the same line).

https://github.com/llvm/llvm-project/pull/161696