[lldb] [llvm] [NFC][DebugInfo] Make some block-start-position methods return iterators (PR #124287)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -448,6 +455,9 @@ BasicBlock::const_iterator BasicBlock::getFirstNonPHIOrDbgOrAlloca() const {
       ++InsertPt;
     }
   }
+
+  // Signal that this comes after any debug records.
+  InsertPt.setHeadBit(false);
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OCHyams wrote:

And again

https://github.com/llvm/llvm-project/pull/124287