Index: lib/Target/Mips/MipsHazardSchedule.cpp
===================================================================
--- lib/Target/Mips/MipsHazardSchedule.cpp
+++ lib/Target/Mips/MipsHazardSchedule.cpp
@@ -103,23 +103,24 @@
 
 // Find the next real instruction from the current position, looking through
 // basic block boundaries.
-static Iter getNextMachineInstr(Iter Position, MachineBasicBlock *Parent) {
+static std::pair<Iter, bool> getNextMachineInstr(Iter Position, MachineBasicBlock * Parent) {
   if (Position == Parent->end()) {
-    MachineBasicBlock *Succ = Parent->getNextNode();
-    if (Succ != nullptr && Parent->isSuccessor(Succ)) {
-      Position = Succ->begin();
-      Parent = Succ;
-    } else {
-      llvm_unreachable(
-          "Should have identified the end of the function earlier!");
-    }
+    do {
+      MachineBasicBlock *Succ = Parent->getNextNode();
+      if (Succ != nullptr && Parent->isSuccessor(Succ)) {
+        Position = Succ->begin();
+        Parent = Succ;
+      } else {
+        return std::make_pair(Position, true);
+      }
+    } while (Parent->empty());
   }
 
   Iter Instr = getNextMachineInstrInBB(Position);
   if (Instr == Parent->end()) {
     return getNextMachineInstr(Instr, Parent);
   }
-  return Instr;
+  return std::make_pair(Instr, false);
 }
 
 bool MipsHazardSchedule::runOnMachineFunction(MachineFunction &MF) {
@@ -145,7 +146,9 @@
       bool LastInstInFunction =
           std::next(I) == FI->end() && std::next(FI) == MF.end();
       if (!LastInstInFunction) {
-        Inst = getNextMachineInstr(std::next(I), &*FI);
+        std::pair<Iter, bool> Res = getNextMachineInstr(std::next(I), &*FI);
+        LastInstInFunction |= Res.second;
+        Inst = Res.first;
       }
 
       if (LastInstInFunction || !TII->SafeInForbiddenSlot(*Inst)) {
Index: test/CodeGen/Mips/compactbranches/empty-block.mir
===================================================================
--- /dev/null
+++ test/CodeGen/Mips/compactbranches/empty-block.mir
@@ -0,0 +1,92 @@
+# RUN: llc -march=mipsel -mcpu=mips32r6 -start-after=block-placement %s -o - | FileCheck %s
+
+# Check that empty blocks in the cfg don't cause the mips hazard scheduler to
+# crash and that the nop is inserted correctly.
+
+# CHECK:  blezc
+# CHECK:  nop
+# CHECK: # BB#1:
+# CHECK:  .insn
+# CHECK: # BB#2:
+# CHECK:  .insn
+# CHECK: # BB#3:
+# CHECK:  jal
+
+--- |
+  ; ModuleID = '<stdin>'
+  source_filename = "<stdin>"
+  target datalayout = "e-m:m-p:32:32-i8:8:32-i16:16:32-i64:64-n32-S64"
+
+  declare i32 @k()
+
+  declare void @f(i32)
+
+  define void @l5() {
+  entry:
+    %call = tail call i32 @k()
+    %cmp = icmp sgt i32 %call, 0
+    br i1 %cmp, label %if.then, label %if.end
+
+  if.then:                                          ; preds = %entry
+    tail call void @f(i32 signext 2)
+    br label %if.end
+
+  if.end:                                           ; preds = %if.then, %entry
+    ret void
+  }
+
+---
+name:            l5
+alignment:       2
+exposesReturnsTwice: false
+noVRegs:         true
+legalized:       false
+regBankSelected: false
+selected:        false
+tracksRegLiveness: true
+frameInfo:
+  isFrameAddressTaken: false
+  isReturnAddressTaken: false
+  hasStackMap:     false
+  hasPatchPoint:   false
+  stackSize:       24
+  offsetAdjustment: 0
+  maxAlignment:    4
+  adjustsStack:    true
+  hasCalls:        true
+  maxCallFrameSize: 16
+  hasOpaqueSPAdjustment: false
+  hasVAStart:      false
+  hasMustTailInVarArgFunc: false
+stack:
+  - { id: 0, type: spill-slot, offset: -4, size: 4, alignment: 4, callee-saved-register: '%ra' }
+body:             |
+  bb.0.entry:
+    successors: %bb.1.if.then(0x50000000), %bb.4.if.end(0x30000000)
+    liveins: %ra
+
+    %sp = ADDiu %sp, -24
+    CFI_INSTRUCTION def_cfa_offset 24
+    SW killed %ra, %sp, 20 :: (store 4 into %stack.0)
+    CFI_INSTRUCTION offset %ra_64, -4
+    JAL @k, csr_o32_fp64, implicit-def dead %ra, implicit-def %sp, implicit-def %v0
+    BLEZ %v0, %bb.4.if.end, implicit-def %at
+
+  bb.1.if.then:
+    successors: %bb.2.if.then(0x80000000)
+
+  bb.2.if.then:
+    successors: %bb.3.if.then(0x80000000)
+
+  bb.3.if.then:
+    successors: %bb.4.if.end(0x80000000)
+
+    %a0 = ADDiu %zero, 2
+    JAL @f, csr_o32_fp64, implicit-def dead %ra, implicit killed %a0, implicit-def %sp
+
+  bb.4.if.end:
+    %ra = LW %sp, 20 :: (load 4 from %stack.0)
+    %sp = ADDiu %sp, 24
+    PseudoReturn undef %ra
+
+...