[clang] [CIR] Make collectUnreachable more robust (PR #197334)

[Erich Keane via cfe-commits]

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@@ -30,6 +32,13 @@ mlir::Block *replaceCallWithTryCall(cir::CallOp callOp, mlir::Block *unwindDest,
                                     mlir::Location loc,
                                     mlir::RewriterBase &rewriter);
 
+/// Collect ops in blocks that are unreachable from their region's entry,
+/// appending them to \p ops. Used by CIR passes that drive
+/// `applyPartialConversion` and need to feed it operations the conversion
+/// driver's dominance-order traversal would otherwise skip.
+void collectUnreachable(mlir::Operation *parent,
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erichkeane wrote:

Ah, I see... yeah, I think it is worth leaving as is then.  

https://github.com/llvm/llvm-project/pull/197334