Index: lib/Transforms/Vectorize/SLPVectorizer.cpp
===================================================================
--- lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -304,7 +304,8 @@
   typedef SmallVector<Instruction *, 16> InstrList;
   typedef SmallPtrSet<Value *, 16> ValueSet;
   typedef SmallVector<StoreInst *, 8> StoreList;
-  typedef MapVector<Value *, SmallVector<DebugLoc, 2>> ExtraValueToDebugLocsMap;
+  typedef MapVector<Value *, SmallVector<Instruction *, 2>>
+      ExtraValueToDebugLocsMap;
 
   BoUpSLP(Function *Func, ScalarEvolution *Se, TargetTransformInfo *Tti,
           TargetLibraryInfo *TLi, AliasAnalysis *Aa, LoopInfo *Li,
@@ -4444,7 +4445,7 @@
     // The same extra argument may be used several time, so log each attempt
     // to use it.
     for (auto &Pair : ExtraArgs)
-      ExternallyUsedValues[Pair.second].push_back(Pair.first->getDebugLoc());
+      ExternallyUsedValues[Pair.second].push_back(Pair.first);
     while (i < NumReducedVals - ReduxWidth + 1 && ReduxWidth > 2) {
       auto VL = makeArrayRef(&ReducedVals[i], ReduxWidth);
       V.buildTree(VL, ExternallyUsedValues, ReductionOps);
@@ -4495,10 +4496,11 @@
         assert(!Pair.second.empty() &&
                "At least one DebugLoc must be inserted");
         // Add each externally used value to the final reduction.
-        for (auto &DL : Pair.second) {
-          Builder.SetCurrentDebugLocation(DL);
+        for (auto *I : Pair.second) {
+          Builder.SetCurrentDebugLocation(I->getDebugLoc());
           VectorizedTree = Builder.CreateBinOp(ReductionOpcode, VectorizedTree,
                                                Pair.first, "bin.extra");
+          propagateIRFlags(VectorizedTree, I);
         }
       }
       // Update users.
Index: test/Transforms/SLPVectorizer/X86/horizontal-list.ll
===================================================================
--- test/Transforms/SLPVectorizer/X86/horizontal-list.ll
+++ test/Transforms/SLPVectorizer/X86/horizontal-list.ll
@@ -1679,8 +1679,8 @@
 ; CHECK-NEXT:    [[RDX_SHUF1:%.*]] = shufflevector <4 x i32> [[BIN_RDX]], <4 x i32> undef, <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef>
 ; CHECK-NEXT:    [[BIN_RDX2:%.*]] = add <4 x i32> [[BIN_RDX]], [[RDX_SHUF1]]
 ; CHECK-NEXT:    [[TMP12:%.*]] = extractelement <4 x i32> [[BIN_RDX2]], i32 0
-; CHECK-NEXT:    [[BIN_EXTRA:%.*]] = add i32 [[TMP12]], [[ARG]]
-; CHECK-NEXT:    [[BIN_EXTRA3:%.*]] = add i32 [[BIN_EXTRA]], [[TMP9]]
+; CHECK-NEXT:    [[BIN_EXTRA:%.*]] = add nuw i32 [[TMP12]], [[ARG]]
+; CHECK-NEXT:    [[BIN_EXTRA3:%.*]] = add nsw i32 [[BIN_EXTRA]], [[TMP9]]
 ; CHECK-NEXT:    [[R5:%.*]] = add nsw i32 [[R4]], undef
 ; CHECK-NEXT:    ret i32 [[BIN_EXTRA3]]
 ;
@@ -1707,8 +1707,8 @@
 ; THRESHOLD-NEXT:    [[RDX_SHUF1:%.*]] = shufflevector <4 x i32> [[BIN_RDX]], <4 x i32> undef, <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef>
 ; THRESHOLD-NEXT:    [[BIN_RDX2:%.*]] = add <4 x i32> [[BIN_RDX]], [[RDX_SHUF1]]
 ; THRESHOLD-NEXT:    [[TMP12:%.*]] = extractelement <4 x i32> [[BIN_RDX2]], i32 0
-; THRESHOLD-NEXT:    [[BIN_EXTRA:%.*]] = add i32 [[TMP12]], [[ARG]]
-; THRESHOLD-NEXT:    [[BIN_EXTRA3:%.*]] = add i32 [[BIN_EXTRA]], [[TMP9]]
+; THRESHOLD-NEXT:    [[BIN_EXTRA:%.*]] = add nuw i32 [[TMP12]], [[ARG]]
+; THRESHOLD-NEXT:    [[BIN_EXTRA3:%.*]] = add nsw i32 [[BIN_EXTRA]], [[TMP9]]
 ; THRESHOLD-NEXT:    [[R5:%.*]] = add nsw i32 [[R4]], undef
 ; THRESHOLD-NEXT:    ret i32 [[BIN_EXTRA3]]
 ;