diff --git a/llvm/include/llvm/CodeGen/GlobalISel/Localizer.h b/llvm/include/llvm/CodeGen/GlobalISel/Localizer.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/Localizer.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/Localizer.h
@@ -21,6 +21,7 @@
 #ifndef LLVM_CODEGEN_GLOBALISEL_LOCALIZER_H
 #define LLVM_CODEGEN_GLOBALISEL_LOCALIZER_H
 
+#include "llvm/ADT/SetVector.h"
 #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 
@@ -60,12 +61,14 @@
   /// Initialize the field members using \p MF.
   void init(MachineFunction &MF);
 
+  typedef SmallSetVector<MachineInstr *, 32> LocalizedSetVecT;
+
   /// Do inter-block localization from the entry block.
   bool localizeInterBlock(MachineFunction &MF,
-                          SmallPtrSetImpl<MachineInstr *> &LocalizedInstrs);
+                          LocalizedSetVecT &LocalizedInstrs);
 
   /// Do intra-block localization of already localized instructions.
-  bool localizeIntraBlock(SmallPtrSetImpl<MachineInstr *> &LocalizedInstrs);
+  bool localizeIntraBlock(LocalizedSetVecT &LocalizedInstrs);
 
 public:
   Localizer();
diff --git a/llvm/lib/CodeGen/GlobalISel/Localizer.cpp b/llvm/lib/CodeGen/GlobalISel/Localizer.cpp
--- a/llvm/lib/CodeGen/GlobalISel/Localizer.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/Localizer.cpp
@@ -12,7 +12,6 @@
 #include "llvm/CodeGen/GlobalISel/Localizer.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/Support/Debug.h"
 
@@ -76,6 +75,7 @@
   case TargetOpcode::G_CONSTANT:
   case TargetOpcode::G_FCONSTANT:
   case TargetOpcode::G_FRAME_INDEX:
+  case TargetOpcode::G_INTTOPTR:
     return true;
   case TargetOpcode::G_GLOBAL_VALUE: {
     unsigned RematCost = TTI->getGISelRematGlobalCost();
@@ -104,8 +104,8 @@
   return InsertMBB == Def.getParent();
 }
 
-bool Localizer::localizeInterBlock(
-    MachineFunction &MF, SmallPtrSetImpl<MachineInstr *> &LocalizedInstrs) {
+bool Localizer::localizeInterBlock(MachineFunction &MF,
+                                   LocalizedSetVecT &LocalizedInstrs) {
   bool Changed = false;
   DenseMap<std::pair<MachineBasicBlock *, unsigned>, unsigned> MBBWithLocalDef;
 
@@ -114,7 +114,8 @@
   // we only localize instructions in the entry block here. This might change if
   // we start doing CSE across blocks.
   auto &MBB = MF.front();
-  for (MachineInstr &MI : MBB) {
+  for (auto RI = MBB.rbegin(), RE = MBB.rend(); RI != RE; ++RI) {
+    MachineInstr &MI = *RI;
     if (!shouldLocalize(MI))
       continue;
     LLVM_DEBUG(dbgs() << "Should localize: " << MI);
@@ -166,8 +167,7 @@
   return Changed;
 }
 
-bool Localizer::localizeIntraBlock(
-    SmallPtrSetImpl<MachineInstr *> &LocalizedInstrs) {
+bool Localizer::localizeIntraBlock(LocalizedSetVecT &LocalizedInstrs) {
   bool Changed = false;
 
   // For each already-localized instruction which has multiple users, then we
@@ -179,15 +179,16 @@
   for (MachineInstr *MI : LocalizedInstrs) {
     unsigned Reg = MI->getOperand(0).getReg();
     MachineBasicBlock &MBB = *MI->getParent();
-    // If the instruction has a single use, we would have already moved it right
-    // before its user in localizeInterBlock().
-    if (MRI->hasOneUse(Reg))
-      continue;
-
     // All of the user MIs of this reg.
     SmallPtrSet<MachineInstr *, 32> Users;
-    for (MachineInstr &UseMI : MRI->use_nodbg_instructions(Reg))
-      Users.insert(&UseMI);
+    for (MachineInstr &UseMI : MRI->use_nodbg_instructions(Reg)) {
+      if (!UseMI.isPHI())
+        Users.insert(&UseMI);
+    }
+    // If all the users were PHIs then they're not going to be in our block,
+    // don't try to move this instruction.
+    if (Users.empty())
+      continue;
 
     MachineBasicBlock::iterator II(MI);
     ++II;
@@ -216,7 +217,7 @@
 
   // Keep track of the instructions we localized. We'll do a second pass of
   // intra-block localization to further reduce live ranges.
-  SmallPtrSet<MachineInstr *, 32> LocalizedInstrs;
+  LocalizedSetVecT LocalizedInstrs;
 
   bool Changed = localizeInterBlock(MF, LocalizedInstrs);
   return Changed |= localizeIntraBlock(LocalizedInstrs);
diff --git a/llvm/test/CodeGen/AArch64/GlobalISel/localizer.mir b/llvm/test/CodeGen/AArch64/GlobalISel/localizer.mir
--- a/llvm/test/CodeGen/AArch64/GlobalISel/localizer.mir
+++ b/llvm/test/CodeGen/AArch64/GlobalISel/localizer.mir
@@ -38,6 +38,8 @@
     ret i32 0
   }
 
+  define void @test_inttoptr() { ret void }
+
 ...
 
 ---
@@ -350,8 +352,8 @@
   ; CHECK:   [[GV3:%[0-9]+]]:gpr(p0) = G_GLOBAL_VALUE @var2
   ; CHECK:   [[C4:%[0-9]+]]:gpr(s32) = G_CONSTANT i32 2
   ; CHECK:   G_STORE [[C4]](s32), [[GV3]](p0) :: (store 4 into @var2)
-  ; CHECK:   [[GV4:%[0-9]+]]:gpr(p0) = G_GLOBAL_VALUE @var1
   ; CHECK:   [[C5:%[0-9]+]]:gpr(s32) = G_CONSTANT i32 3
+  ; CHECK:   [[GV4:%[0-9]+]]:gpr(p0) = G_GLOBAL_VALUE @var1
   ; CHECK:   G_STORE [[C5]](s32), [[GV4]](p0) :: (store 4 into @var1)
   ; CHECK:   [[GV5:%[0-9]+]]:gpr(p0) = G_GLOBAL_VALUE @var3
   ; CHECK:   G_STORE [[C4]](s32), [[GV5]](p0) :: (store 4 into @var3)
@@ -388,3 +390,63 @@
     RET_ReallyLR implicit $w0
 
 ...
+---
+name:            test_inttoptr
+alignment:       2
+legalized:       true
+regBankSelected: true
+tracksRegLiveness: true
+body:             |
+  ; CHECK-LABEL: name: test_inttoptr
+  ; CHECK: bb.0:
+  ; CHECK:   successors: %bb.1(0x40000000), %bb.2(0x40000000)
+  ; CHECK:   liveins: $w0, $x1
+  ; CHECK:   [[COPY:%[0-9]+]]:gpr(s32) = COPY $w0
+  ; CHECK:   [[COPY1:%[0-9]+]]:gpr(p0) = COPY $x1
+  ; CHECK:   [[C:%[0-9]+]]:gpr(s64) = G_CONSTANT i64 128
+  ; CHECK:   [[C1:%[0-9]+]]:gpr(s32) = G_CONSTANT i32 0
+  ; CHECK:   [[C2:%[0-9]+]]:gpr(s64) = G_CONSTANT i64 0
+  ; CHECK:   [[INTTOPTR:%[0-9]+]]:gpr(p0) = G_INTTOPTR [[C2]](s64)
+  ; CHECK:   [[INTTOPTR1:%[0-9]+]]:gpr(p0) = G_INTTOPTR [[C]](s64)
+  ; CHECK:   [[ICMP:%[0-9]+]]:gpr(s32) = G_ICMP intpred(eq), [[COPY]](s32), [[C1]]
+  ; CHECK:   [[TRUNC:%[0-9]+]]:gpr(s1) = G_TRUNC [[ICMP]](s32)
+  ; CHECK:   G_BRCOND [[TRUNC]](s1), %bb.1
+  ; CHECK:   G_BR %bb.2
+  ; CHECK: bb.1:
+  ; CHECK:   [[ADD:%[0-9]+]]:gpr(s32) = G_ADD [[COPY]], [[COPY]]
+  ; CHECK:   G_STORE [[ADD]](s32), [[COPY1]](p0) :: (store 4)
+  ; CHECK:   [[C3:%[0-9]+]]:gpr(s64) = G_CONSTANT i64 128
+  ; CHECK:   [[INTTOPTR2:%[0-9]+]]:gpr(p0) = G_INTTOPTR [[C3]](s64)
+  ; CHECK:   $x0 = COPY [[INTTOPTR2]](p0)
+  ; CHECK:   RET_ReallyLR implicit $x0
+  ; CHECK: bb.2:
+  ; CHECK:   [[C4:%[0-9]+]]:gpr(s64) = G_CONSTANT i64 0
+  ; CHECK:   [[INTTOPTR3:%[0-9]+]]:gpr(p0) = G_INTTOPTR [[C4]](s64)
+  ; CHECK:   $x0 = COPY [[INTTOPTR3]](p0)
+  ; CHECK:   RET_ReallyLR implicit $x0
+  bb.1:
+    liveins: $w0, $x1
+
+    %0:gpr(s32) = COPY $w0
+    %1:gpr(p0) = COPY $x1
+    %2:gpr(s64) = G_CONSTANT i64 128
+    %4:gpr(s32) = G_CONSTANT i32 0
+    %7:gpr(s64) = G_CONSTANT i64 0
+    %6:gpr(p0) = G_INTTOPTR %7(s64)
+    %3:gpr(p0) = G_INTTOPTR %2(s64)
+    %9:gpr(s32) = G_ICMP intpred(eq), %0(s32), %4
+    %5:gpr(s1) = G_TRUNC %9(s32)
+    G_BRCOND %5(s1), %bb.2
+    G_BR %bb.3
+
+  bb.2:
+    %8:gpr(s32) = G_ADD %0, %0
+    G_STORE %8(s32), %1(p0) :: (store 4)
+    $x0 = COPY %3(p0)
+    RET_ReallyLR implicit $x0
+
+  bb.3:
+    $x0 = COPY %6(p0)
+    RET_ReallyLR implicit $x0
+
+...