[llvm] [RemoveDIs][DebugInfo] Add DPVAssign variant of DPValue (PR #77912)

[Jeremy Morse via llvm-commits]

================
@@ -117,6 +120,22 @@ class DPValue : public ilist_node<DPValue>, private DebugValueUser {
   /// assigning \p Location to the DV / Expr / DI variable.
   DPValue(Metadata *Location, DILocalVariable *DV, DIExpression *Expr,
           const DILocation *DI, LocationType Type = LocationType::Value);
+  DPValue(Metadata *Value, DILocalVariable *Variable, DIExpression *Expression,
+          DIAssignID *AssignID, Metadata *Address,
+          DIExpression *AddressExpression, const DILocation *DI);
+
+  static DPValue *createDPVAssign(Metadata *Value, DILocalVariable *Variable,
+                                  DIExpression *Expression,
+                                  DIAssignID *AssignID, Metadata *Address,
+                                  DIExpression *AddressExpression,
+                                  const DILocation *DI,
+                                  Instruction *InsertBefore = nullptr);
----------------
jmorse wrote:

This is going to want to be a BasicBlock::iterator so that we can take the head bit

https://github.com/llvm/llvm-project/pull/77912