[llvm] GlobalISel lane masks merging (PR #73337)

[Matt Arsenault via llvm-commits]

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@@ -197,8 +192,8 @@ Register MachineSSAUpdater::GetValueInMiddleOfBlock(MachineBasicBlock *BB,
 
   // Otherwise, we do need a PHI: insert one now.
   MachineBasicBlock::iterator Loc = BB->empty() ? BB->end() : BB->begin();
-  MachineInstrBuilder InsertedPHI = InsertNewDef(TargetOpcode::PHI, BB,
-                                                 Loc, VRC, MRI, TII);
+  MachineInstrBuilder InsertedPHI =
+      InsertNewDef(TargetOpcode::PHI, BB, Loc, RegAttrs, MRI, TII);
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arsenm wrote:

Same as with IMPLICIT_DEF, G_PHI for generic virtual registers 

https://github.com/llvm/llvm-project/pull/73337