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

[Matt Arsenault via llvm-commits]

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@@ -300,10 +295,9 @@ class SSAUpdaterTraits<MachineSSAUpdater> {
   static Register GetUndefVal(MachineBasicBlock *BB,
                               MachineSSAUpdater *Updater) {
     // Insert an implicit_def to represent an undef value.
-    MachineInstr *NewDef = InsertNewDef(TargetOpcode::IMPLICIT_DEF,
-                                        BB, BB->getFirstNonPHI(),
-                                        Updater->VRC, Updater->MRI,
-                                        Updater->TII);
+    MachineInstr *NewDef =
+        InsertNewDef(TargetOpcode::IMPLICIT_DEF, BB, BB->getFirstNonPHI(),
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arsenm wrote:

Ditto 

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