Index: lib/Transforms/Utils/SimplifyIndVar.cpp
===================================================================
--- lib/Transforms/Utils/SimplifyIndVar.cpp
+++ lib/Transforms/Utils/SimplifyIndVar.cpp
@@ -19,7 +19,7 @@
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/LoopPass.h"
-#include "llvm/Analysis/ScalarEvolutionExpressions.h"
+#include "llvm/Analysis/ScalarEvolutionExpander.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/IRBuilder.h"
@@ -77,7 +77,7 @@
     Value *foldIVUser(Instruction *UseInst, Instruction *IVOperand);
 
     bool eliminateIdentitySCEV(Instruction *UseInst, Instruction *IVOperand);
-    bool foldConstantSCEV(Instruction *UseInst);
+    bool replaceIVUserWithLoopInvariant(Instruction *UseInst);
 
     bool eliminateOverflowIntrinsic(CallInst *CI);
     bool eliminateIVUser(Instruction *UseInst, Instruction *IVOperand);
@@ -537,7 +537,7 @@
 }
 
 /// Replace the UseInst with a constant if possible
-bool SimplifyIndvar::foldConstantSCEV(Instruction *I) {
+bool SimplifyIndvar::replaceIVUserWithLoopInvariant(Instruction *I) {
   if (!SE->isSCEVable(I->getType()))
     return false;
 
@@ -546,21 +546,16 @@
 
   const Loop *L = LI->getLoopFor(I->getParent());
   S = SE->getSCEVAtScope(S, L);
-  auto *C = dyn_cast<SCEVConstant>(S);
 
-  if (!C)
+  if (!SE->isLoopInvariant(S, L))
     return false;
 
-  Constant *V = C->getValue();
-  // The SCEV will have a different type than the instruction if the instruction
-  // has a pointer type. Skip the replacement
-  // TODO: Replace ConstantInt Zero by ConstantPointerNull
-  if (V->getType() != I->getType())
-    return false;
+  SCEVExpander Expander(*SE, SE->getDataLayout(), "loop.invarant");
+  auto *Invariant = Expander.expandCodeFor(S, I->getType(), I);
 
-  I->replaceAllUsesWith(V);
-  DEBUG(dbgs() << "INDVARS: Replace IV user: " << *I << " with constant: " << *C
-               << '\n');
+  I->replaceAllUsesWith(Invariant);
+  DEBUG(dbgs() << "INDVARS: Replace IV user: " << *I
+               << " with loop invariant: " << *S << '\n');
   ++NumFoldedUser;
   Changed = true;
   DeadInsts.emplace_back(I);
@@ -774,8 +769,9 @@
     // Bypass back edges to avoid extra work.
     if (UseInst == CurrIV) continue;
 
-    // Try to replace UseInst with a constant before any other simplifications
-    if (foldConstantSCEV(UseInst))
+    // Try to replace UseInst with a loop invariant before any other
+    // simplifications
+    if (replaceIVUserWithLoopInvariant(UseInst))
       continue;
 
     Instruction *IVOperand = UseOper.second;
Index: test/Transforms/IndVarSimplify/constant-fold-1.ll
===================================================================
--- test/Transforms/IndVarSimplify/constant-fold-1.ll
+++ /dev/null
@@ -1,39 +0,0 @@
-; RUN: opt < %s -indvars -S | FileCheck %s
-
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-target triple = "x86_64-unknown-linux-gnu"
-
-define void @test(i64* %arg) unnamed_addr align 2 {
-bb:
-  switch i64 undef, label %bb1 [
-  ]
-
-bb1:                                              ; preds = %bb
-  br label %bb2
-
-bb2:                                              ; preds = %bb6, %bb1
-  %tmp = phi i64* [%arg, %bb1 ], [ %tmp7, %bb6 ]
-  switch i2 undef, label %bb6 [
-    i2 1, label %bb5
-    i2 -2, label %bb3
-    i2 -1, label %bb3
-  ]
-
-bb3:                                              ; preds = %bb2, %bb2
-  %tmp4 = call fastcc i32* @wobble(i64* nonnull %tmp, i32* null)
-  %tmp5 = load i32, i32* %tmp4 , align 8
-  br label %bb6
-
-bb5:                                              ; preds = %bb2
-  unreachable
-
-bb6:                                              ; preds = %bb3, %bb2
-  %tmp7 = load i64*, i64** undef, align 8
-  br label %bb2
-}
-
-declare i32* @wobble(i64*, i32* returned)
-
-; Should not fail when SCEV is fold to ConstantPointerNull
-; CHECK-LABEL: void @test
-; CHECK:         load i32, i32* %{{[a-zA-Z$._0-9]+}}
Index: test/Transforms/IndVarSimplify/replace-iv-with-loop-invariant.ll
===================================================================
--- /dev/null
+++ test/Transforms/IndVarSimplify/replace-iv-with-loop-invariant.ll
@@ -0,0 +1,69 @@
+; RUN: opt < %s -indvars -S | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@G = external global i32
+
+define void @test0(i64* %arg) {
+bb:
+  br label %bb2
+
+bb2:
+  %tmp = phi i64* [%arg, %bb ], [ %tmp7, %bb2 ]
+  %tmp4 = call i32* @wobble(i64* nonnull %tmp, i32* null)
+  %tmp5 = load i32, i32* %tmp4, align 8
+  %tmp7 = load i64*, i64** undef, align 8
+  br label %bb2
+}
+
+; CHECK-LABEL: void @test0
+; CHECK:         load i32, i32* null
+
+define void @test1(i64* %arg) {
+bb:
+  br label %bb2
+
+bb2:
+  %tmp = phi i64* [%arg, %bb ], [ %tmp7, %bb2 ]
+  %tmp4 = call i32* @wobble(i64* nonnull %tmp, i32* inttoptr (i64 4 to i32*))
+  %tmp5 = load i32, i32* %tmp4
+  %tmp7 = load i64*, i64** undef, align 8
+  br label %bb2
+}
+
+; CHECK-LABEL: void @test1
+; CHECK:         load i32, i32* inttoptr (i64 4 to i32*)
+
+define void @test2(i64* %arg) {
+bb:
+  br label %bb2
+
+bb2:
+  %tmp = phi i64* [%arg, %bb ], [ %tmp7, %bb2 ]
+  %tmp4 = call i32* @wobble(i64* nonnull %tmp, i32* @G)
+  %tmp5 = load i32, i32* %tmp4
+  %tmp7 = load i64*, i64** undef, align 8
+  br label %bb2
+}
+
+; CHECK-LABEL: void @test2
+; CHECK:         load i32, i32* @G
+
+
+define void @test3(i64* %arg, i32* %loop.invariant) {
+bb:
+  br label %bb2
+
+bb2:
+  %tmp = phi i64* [%arg, %bb ], [ %tmp7, %bb2 ]
+  %tmp4 = call i32* @wobble(i64* nonnull %tmp, i32* %loop.invariant)
+  %tmp5 = load i32, i32* %tmp4
+  %tmp7 = load i64*, i64** undef, align 8
+  br label %bb2
+}
+
+; CHECK-LABEL: void @test3
+; CHECK:         load i32, i32* %loop.invariant
+
+declare i32* @wobble(i64*, i32* returned)