SIL: need to clear the bitfield ID when moving instructions between functions

I forgot to do this when introducing the `NodeBitfield`.

rdar://97095506

Author: eeckstein

lib/SIL/IR/SILInstruction.cpp

@@ -77,12 +77,21 @@ transferNodesFromList(llvm::ilist_traits<SILInstruction> &L2,
   // If transferring instructions within the same basic block, no reason to
   // update their parent pointers.
   SILBasicBlock *ThisParent = getContainingBlock();
-  if (ThisParent == L2.getContainingBlock()) return;
+  SILBasicBlock *l2Block = L2.getContainingBlock();
+  if (ThisParent == l2Block) return;
+  
+  bool differentFunctions = (ThisParent->getFunction() != l2Block->getFunction());
 
   // Update the parent fields in the instructions.
   for (; first != last; ++first) {
     SWIFT_FUNC_STAT_NAMED("sil");
     first->ParentBB = ThisParent;
+    if (differentFunctions) {
+      for (SILValue result : first->getResults()) {
+        result->resetBitfields();
+      }
+      first->asSILNode()->resetBitfields();
+    }
   }
 }