diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index 125f2cbc516..190fc5a2dc4 100644
--- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -4315,7 +4315,33 @@ BasicBlock::iterator
 LSRInstance::HoistInsertPosition(BasicBlock::iterator IP,
                                  const SmallVectorImpl<Instruction *> &Inputs)
                                                                          const {
+  Instruction *Tentative = &*IP;
   for (;;) {
+    bool AllDominate = true;
+    Instruction *BetterPos = nullptr;
+    // Don't bother attempting to insert before a catchswitch, their basic block
+    // cannot have other non-PHI instructions.
+    if (isa<CatchSwitchInst>(Tentative))
+      return IP;
+
+    for (Instruction *Inst : Inputs) {
+      if (Inst == Tentative || !DT.dominates(Inst, Tentative)) {
+        AllDominate = false;
+        break;
+      }
+      // Attempt to find an insert position in the middle of the block,
+      // instead of at the end, so that it can be used for other expansions.
+      if (Tentative->getParent() == Inst->getParent() &&
+          (!BetterPos || !DT.dominates(Inst, BetterPos)))
+        BetterPos = &*std::next(BasicBlock::iterator(Inst));
+    }
+    if (!AllDominate)
+      break;
+    if (BetterPos)
+      IP = BetterPos->getIterator();
+    else
+      IP = Tentative->getIterator();
+
     const Loop *IPLoop = LI.getLoopFor(IP->getParent());
     unsigned IPLoopDepth = IPLoop ? IPLoop->getLoopDepth() : 0;
 
@@ -4334,31 +4360,7 @@ LSRInstance::HoistInsertPosition(BasicBlock::iterator IP,
         break;
     }
 
-    bool AllDominate = true;
-    Instruction *BetterPos = nullptr;
-    Instruction *Tentative = IDom->getTerminator();
-    // Don't bother attempting to insert before a catchswitch, their basic block
-    // cannot have other non-PHI instructions.
-    if (isa<CatchSwitchInst>(Tentative))
-      return IP;
-
-    for (Instruction *Inst : Inputs) {
-      if (Inst == Tentative || !DT.dominates(Inst, Tentative)) {
-        AllDominate = false;
-        break;
-      }
-      // Attempt to find an insert position in the middle of the block,
-      // instead of at the end, so that it can be used for other expansions.
-      if (IDom == Inst->getParent() &&
-          (!BetterPos || !DT.dominates(Inst, BetterPos)))
-        BetterPos = &*std::next(BasicBlock::iterator(Inst));
-    }
-    if (!AllDominate)
-      break;
-    if (BetterPos)
-      IP = BetterPos->getIterator();
-    else
-      IP = Tentative->getIterator();
+    Tentative = IDom->getTerminator();
   }
 
   return IP;
diff --git a/test/Transforms/LoopStrengthReduce/AArch64/lsr-reuse.ll b/test/Transforms/LoopStrengthReduce/AArch64/lsr-reuse.ll
new file mode 100644
index 00000000000..a2dfe81b108
--- /dev/null
+++ b/test/Transforms/LoopStrengthReduce/AArch64/lsr-reuse.ll
@@ -0,0 +1,34 @@
+; RUN: llc -mtriple=arm64-unknown-unknown -print-lsr-output < %s 2>&1 | FileCheck %s
+
+declare void @foo(i64)
+
+; Verify that redundant adds aren't inserted by LSR.
+; CHECK-LABEL: @bar(
+define void @bar(double* %A) {
+entry:
+  br label %while.cond
+
+while.cond:
+; CHECK-LABEL: while.cond:
+; CHECK: add i64 %lsr.iv, 1
+; CHECK-NOT: add i64 %lsr.iv, 1
+; CHECK-LABEL: land.rhs:
+  %indvars.iv28 = phi i64 [ %indvars.iv.next29, %land.rhs ], [ 50, %entry ]
+  %cmp = icmp sgt i64 %indvars.iv28, 0
+  br i1 %cmp, label %land.rhs, label %while.end
+
+land.rhs:
+  %indvars.iv.next29 = add nsw i64 %indvars.iv28, -1
+  %arrayidx = getelementptr inbounds double, double* %A, i64 %indvars.iv.next29
+  %Aload = load double, double* %arrayidx, align 8
+  %cmp1 = fcmp oeq double %Aload, 0.000000e+00
+  br i1 %cmp1, label %while.cond, label %if.end
+
+while.end:
+  %indvars.iv28.lcssa = phi i64 [ %indvars.iv28, %while.cond ]
+  tail call void @foo(i64 %indvars.iv28.lcssa)
+  br label %if.end
+
+if.end:
+  ret void
+}
diff --git a/test/Transforms/LoopStrengthReduce/scev-insertpt-bug.ll b/test/Transforms/LoopStrengthReduce/scev-insertpt-bug.ll
new file mode 100644
index 00000000000..81a6b07fe95
--- /dev/null
+++ b/test/Transforms/LoopStrengthReduce/scev-insertpt-bug.ll
@@ -0,0 +1,47 @@
+; RUN: opt < %s -loop-reduce -S
+
+; Test that SCEV insertpoint's don't get corrupted and cause an
+; invalid instruction to be inserted in a block other than its parent.
+; See http://reviews.llvm.org/D20703 for context.
+define void @test() {
+entry:
+  %bf.load = load i32, i32* null, align 4
+  %bf.clear = lshr i32 %bf.load, 1
+  %div = and i32 %bf.clear, 134217727
+  %sub = add nsw i32 %div, -1
+  %0 = zext i32 %sub to i64
+  br label %while.cond
+
+while.cond:                                       ; preds = %cond.end, %entry
+  %indvars.iv = phi i64 [ %indvars.iv.next, %cond.end ], [ 0, %entry ]
+  %cmp = icmp eq i64 %indvars.iv, %0
+  br i1 %cmp, label %cleanup16, label %while.body
+
+while.body:                                       ; preds = %while.cond
+  %1 = trunc i64 %indvars.iv to i32
+  %mul = shl i32 %1, 1
+  %add = add nuw i32 %mul, 2
+  %cmp3 = icmp ult i32 %add, 0
+  br i1 %cmp3, label %if.end, label %if.then
+
+if.then:                                          ; preds = %while.body
+  unreachable
+
+if.end:                                           ; preds = %while.body
+  br i1 false, label %cond.end, label %cond.true
+
+cond.true:                                        ; preds = %if.end
+  br label %cond.end
+
+cond.end:                                         ; preds = %cond.true, %if.end
+  %add7 = add i32 %1, 1
+  %cmp12 = icmp ugt i32 %add7, %sub
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  br i1 %cmp12, label %if.then13, label %while.cond
+
+if.then13:                                        ; preds = %cond.end
+  unreachable
+
+cleanup16:                                        ; preds = %while.cond
+  ret void
+}