Index: lib/Target/AArch64/AArch64BranchRelaxation.cpp
===================================================================
--- lib/Target/AArch64/AArch64BranchRelaxation.cpp
+++ lib/Target/AArch64/AArch64BranchRelaxation.cpp
@@ -90,7 +90,7 @@
   void scanFunction();
   MachineBasicBlock *splitBlockBeforeInstr(MachineInstr *MI);
   void adjustBlockOffsets(MachineBasicBlock &MBB);
-  bool isBlockInRange(MachineInstr *MI, MachineBasicBlock *BB, unsigned Disp);
+  bool isBlockInRange(MachineInstr &MI, MachineBasicBlock *BB, unsigned Disp);
   bool fixupConditionalBranch(MachineInstr *MI);
   void computeBlockSize(const MachineBasicBlock &MBB);
   unsigned getInstrOffset(MachineInstr *MI) const;
@@ -262,18 +262,18 @@
 
 /// isBlockInRange - Returns true if the distance between specific MI and
 /// specific BB can fit in MI's displacement field.
-bool AArch64BranchRelaxation::isBlockInRange(MachineInstr *MI,
+bool AArch64BranchRelaxation::isBlockInRange(MachineInstr &MI,
                                              MachineBasicBlock *DestBB,
                                              unsigned Bits) {
   unsigned MaxOffs = ((1 << (Bits - 1)) - 1) << 2;
-  unsigned BrOffset = getInstrOffset(MI);
+  unsigned BrOffset = getInstrOffset(&MI);
   unsigned DestOffset = BlockInfo[DestBB->getNumber()].Offset;
 
   DEBUG(dbgs() << "Branch of destination BB#" << DestBB->getNumber()
-               << " from BB#" << MI->getParent()->getNumber()
-               << " max delta=" << MaxOffs << " from " << getInstrOffset(MI)
+               << " from BB#" << MI.getParent()->getNumber()
+               << " max delta=" << MaxOffs << " from " << BrOffset
                << " to " << DestOffset << " offset "
-               << int(DestOffset - BrOffset) << "\t" << *MI);
+               << int(DestOffset - BrOffset) << '\t' << MI);
 
   // Branch before the Dest.
   if (BrOffset <= DestOffset)
@@ -298,21 +298,21 @@
   }
 }
 
-static MachineBasicBlock *getDestBlock(MachineInstr *MI) {
-  switch (MI->getOpcode()) {
+static MachineBasicBlock *getDestBlock(MachineInstr &MI) {
+  switch (MI.getOpcode()) {
   default:
     llvm_unreachable("unexpected opcode!");
   case AArch64::TBZW:
   case AArch64::TBNZW:
   case AArch64::TBZX:
   case AArch64::TBNZX:
-    return MI->getOperand(2).getMBB();
+    return MI.getOperand(2).getMBB();
   case AArch64::CBZW:
   case AArch64::CBNZW:
   case AArch64::CBZX:
   case AArch64::CBNZX:
   case AArch64::Bcc:
-    return MI->getOperand(1).getMBB();
+    return MI.getOperand(1).getMBB();
   }
 }
 
@@ -362,7 +362,7 @@
 /// too far away to fit in its displacement field. It is converted to an inverse
 /// conditional branch + an unconditional branch to the destination.
 bool AArch64BranchRelaxation::fixupConditionalBranch(MachineInstr *MI) {
-  MachineBasicBlock *DestBB = getDestBlock(MI);
+  MachineBasicBlock *DestBB = getDestBlock(*MI);
 
   // Add an unconditional branch to the destination and invert the branch
   // condition to jump over it:
@@ -391,7 +391,7 @@
       // bne L2
       // b   L1
       MachineBasicBlock *NewDest = BMI->getOperand(0).getMBB();
-      if (isBlockInRange(MI, NewDest,
+      if (isBlockInRange(*MI, NewDest,
                          getBranchDisplacementBits(MI->getOpcode()))) {
         DEBUG(dbgs() << "  Invert condition and swap its destination with "
                      << *BMI);
@@ -465,11 +465,15 @@
   // end() for termination.
   for (MachineFunction::iterator I = MF->begin(); I != MF->end(); ++I) {
     MachineBasicBlock &MBB = *I;
-    MachineInstr *MI = MBB.getFirstTerminator();
-    if (isConditionalBranch(MI->getOpcode()) &&
+    MachineBasicBlock::iterator J = MBB.getFirstTerminator();
+    if (J == MBB.end())
+      continue;
+
+    MachineInstr &MI = *J;
+    if (isConditionalBranch(MI.getOpcode()) &&
         !isBlockInRange(MI, getDestBlock(MI),
-                        getBranchDisplacementBits(MI->getOpcode()))) {
-      fixupConditionalBranch(MI);
+                        getBranchDisplacementBits(MI.getOpcode()))) {
+      fixupConditionalBranch(&MI);
       ++NumRelaxed;
       Changed = true;
     }