diff --git a/llvm/lib/CodeGen/MachineScheduler.cpp b/llvm/lib/CodeGen/MachineScheduler.cpp
--- a/llvm/lib/CodeGen/MachineScheduler.cpp
+++ b/llvm/lib/CodeGen/MachineScheduler.cpp
@@ -198,6 +198,7 @@
 INITIALIZE_PASS_BEGIN(MachineScheduler, DEBUG_TYPE,
                       "Machine Instruction Scheduler", false, false)
 INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
 INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
 INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
 INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
@@ -210,7 +211,7 @@
 
 void MachineScheduler::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.setPreservesCFG();
-  AU.addRequiredID(MachineDominatorsID);
+  AU.addRequired<MachineDominatorTree>();
   AU.addRequired<MachineLoopInfo>();
   AU.addRequired<AAResultsWrapperPass>();
   AU.addRequired<TargetPassConfig>();
@@ -234,7 +235,7 @@
 
 void PostMachineScheduler::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.setPreservesCFG();
-  AU.addRequiredID(MachineDominatorsID);
+  AU.addRequired<MachineDominatorTree>();
   AU.addRequired<MachineLoopInfo>();
   AU.addRequired<TargetPassConfig>();
   MachineFunctionPass::getAnalysisUsage(AU);
diff --git a/llvm/lib/CodeGen/PHIElimination.cpp b/llvm/lib/CodeGen/PHIElimination.cpp
--- a/llvm/lib/CodeGen/PHIElimination.cpp
+++ b/llvm/lib/CodeGen/PHIElimination.cpp
@@ -148,6 +148,7 @@
   MRI = &MF.getRegInfo();
   LV = getAnalysisIfAvailable<LiveVariables>();
   LIS = getAnalysisIfAvailable<LiveIntervals>();
+  auto *MDT = getAnalysisIfAvailable<MachineDominatorTree>();
 
   bool Changed = false;
 
@@ -185,6 +186,9 @@
     MF.DeleteMachineInstr(I.first);
   }
 
+  if (Changed && MDT)
+    MDT->getBase().recalculate(MF);
+
   LoweredPHIs.clear();
   ImpDefs.clear();
   VRegPHIUseCount.clear();
diff --git a/llvm/test/CodeGen/AArch64/tailmerging_in_mbp.ll b/llvm/test/CodeGen/AArch64/tailmerging_in_mbp.ll
--- a/llvm/test/CodeGen/AArch64/tailmerging_in_mbp.ll
+++ b/llvm/test/CodeGen/AArch64/tailmerging_in_mbp.ll
@@ -1,5 +1,4 @@
 ; RUN: llc <%s -mtriple=aarch64-eabi -verify-machine-dom-info | FileCheck %s
-; XFAIL: *
 
 ; CHECK-LABEL: test:
 ; CHECK-LABEL: %cond.false12.i