[llvm] [BOLT] Fix debug line emission for functions in multiple compilation units (PR #151230)

[Alexander Yermolovich via llvm-commits]

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@@ -679,74 +681,104 @@ void BinaryEmitter::emitConstantIslands(BinaryFunction &BF, bool EmitColdPart,
 SMLoc BinaryEmitter::emitLineInfo(const BinaryFunction &BF, SMLoc NewLoc,
                                   SMLoc PrevLoc, bool FirstInstr,
                                   MCSymbol *&InstrLabel) {
-  DWARFUnit *FunctionCU = BF.getDWARFUnit();
-  const DWARFDebugLine::LineTable *FunctionLineTable = BF.getDWARFLineTable();
-  assert(FunctionCU && "cannot emit line info for function without CU");
-
-  DebugLineTableRowRef RowReference = DebugLineTableRowRef::fromSMLoc(NewLoc);
-
-  // Check if no new line info needs to be emitted.
-  if (RowReference == DebugLineTableRowRef::NULL_ROW ||
+  if (NewLoc.getPointer() == nullptr ||
       NewLoc.getPointer() == PrevLoc.getPointer())
     return PrevLoc;
+  const ClusteredRows *Cluster = ClusteredRows::fromSMLoc(NewLoc);
+
+  auto addToLineTable = [&](DebugLineTableRowRef RowReference,
+                            const DWARFUnit *TargetCU, unsigned Flags,
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ayermolo wrote:

Pass by reference if it can't be null, otherwise check.

https://github.com/llvm/llvm-project/pull/151230