Index: llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
===================================================================
--- llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
+++ llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
@@ -1792,20 +1792,49 @@
   // instructions as normal vector adds. This is the only arithmetic vector
   // reduction operation for which we have an instruction.
   static const CostTblEntry CostTblNoPairwise[]{
-      {ISD::ADD, MVT::v8i8,  1},
-      {ISD::ADD, MVT::v16i8, 1},
-      {ISD::ADD, MVT::v4i16, 1},
-      {ISD::ADD, MVT::v8i16, 1},
-      {ISD::ADD, MVT::v4i32, 1},
+      {ISD::ADD, MVT::v8i8,   1},
+      {ISD::ADD, MVT::v16i8,  1},
+      {ISD::ADD, MVT::v4i16,  1},
+      {ISD::ADD, MVT::v8i16,  1},
+      {ISD::ADD, MVT::v4i32,  1},
+      {ISD::OR,  MVT::v8i8,  15},
+      {ISD::OR,  MVT::v16i8, 17},
+      {ISD::OR,  MVT::v4i16,  7},
+      {ISD::OR,  MVT::v8i16,  9},
+      {ISD::OR,  MVT::v4i32,  5},
+      {ISD::OR,  MVT::v2i64,  3},
   };
-
-  if (const auto *Entry = CostTableLookup(CostTblNoPairwise, ISD, MTy))
-    return LT.first * Entry->Cost;
-
+  switch (ISD) {
+  default:
+    break;
+  case ISD::ADD:
+    if (const auto *Entry = CostTableLookup(CostTblNoPairwise, ISD, MTy))
+      return LT.first * Entry->Cost;
+    break;
+  case ISD::OR:
+    if (const auto *Entry = CostTableLookup(CostTblNoPairwise, ISD, MTy)) {
+      auto *ValVTy = cast<FixedVectorType>(ValTy);
+      if (!ValVTy->getElementType()->isIntegerTy(1) &&
+          MTy.getVectorNumElements() <= ValVTy->getNumElements() &&
+          isPowerOf2_32(ValVTy->getNumElements())) {
+        InstructionCost ExtraCost = 0;
+        if (LT.first != 1) {
+          // Type needs to be split, so there is an extra cost of LT.first - 1
+          // arithmetic ops.
+          auto *Ty = FixedVectorType::get(ValTy->getElementType(),
+                                          MTy.getVectorNumElements());
+          ExtraCost = getArithmeticInstrCost(Opcode, Ty, CostKind);
+          ExtraCost *= LT.first - 1;
+        }
+        return Entry->Cost + ExtraCost;
+      }
+    }
+    break;
+  }
   return BaseT::getArithmeticReductionCost(Opcode, ValTy, IsPairwiseForm,
                                            CostKind);
 }

 InstructionCost AArch64TTIImpl::getShuffleCost(TTI::ShuffleKind Kind,
                                                VectorType *Tp,
                                                ArrayRef<int> Mask, int Index,
Index: llvm/test/Analysis/CostModel/AArch64/reduce-or.ll
===================================================================
--- llvm/test/Analysis/CostModel/AArch64/reduce-or.ll
+++ llvm/test/Analysis/CostModel/AArch64/reduce-or.ll
@@ -11,8 +11,23 @@
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 91 for instruction: %V32 = call i1 @llvm.vector.reduce.or.v32i1(<32 x i1> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 181 for instruction: %V64 = call i1 @llvm.vector.reduce.or.v64i1(<64 x i1> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 362 for instruction: %V128 = call i1 @llvm.vector.reduce.or.v128i1(<128 x i1> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: %V1i8 = call i8 @llvm.vector.reduce.or.v1i8(<1 x i8> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 13 for instruction: %V3i8 = call i8 @llvm.vector.reduce.or.v3i8(<3 x i8> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 7 for instruction: %V4i8 = call i8 @llvm.vector.reduce.or.v4i8(<4 x i8> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 15 for instruction: %V8i8 = call i8 @llvm.vector.reduce.or.v8i8(<8 x i8> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 17 for instruction: %V16i8 = call i8 @llvm.vector.reduce.or.v16i8(<16 x i8> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 18 for instruction: %V32i8 = call i8 @llvm.vector.reduce.or.v32i8(<32 x i8> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 20 for instruction: %V64i8 = call i8 @llvm.vector.reduce.or.v64i8(<64 x i8> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 7 for instruction: %V4i16 = call i16 @llvm.vector.reduce.or.v4i16(<4 x i16> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 9 for instruction: %V8i16 = call i16 @llvm.vector.reduce.or.v8i16(<8 x i16> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 10 for instruction: %V16i16 = call i16 @llvm.vector.reduce.or.v16i16(<16 x i16> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 5 for instruction: %V4i32 = call i32 @llvm.vector.reduce.or.v4i32(<4 x i32> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %V8i32 = call i32 @llvm.vector.reduce.or.v8i32(<8 x i32> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %V2i64 = call i64 @llvm.vector.reduce.or.v2i64(<2 x i64> undef)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %V4i64 = call i64 @llvm.vector.reduce.or.v4i64(<4 x i64> undef)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 undef
 ;
+
   %V1   = call i1 @llvm.vector.reduce.or.v1i1(<1 x i1> undef)
   %V2   = call i1 @llvm.vector.reduce.or.v2i1(<2 x i1> undef)
   %V4   = call i1 @llvm.vector.reduce.or.v4i1(<4 x i1> undef)
@@ -21,9 +36,24 @@
   %V32  = call i1 @llvm.vector.reduce.or.v32i1(<32 x i1> undef)
   %V64  = call i1 @llvm.vector.reduce.or.v64i1(<64 x i1> undef)
   %V128 = call i1 @llvm.vector.reduce.or.v128i1(<128 x i1> undef)
+
+  %V1i8 = call i8 @llvm.vector.reduce.or.v1i8(<1 x i8> undef)
+  %V3i8 = call i8 @llvm.vector.reduce.or.v3i8(<3 x i8> undef)
+  %V4i8 = call i8 @llvm.vector.reduce.or.v4i8(<4 x i8> undef)
+  %V8i8 = call i8 @llvm.vector.reduce.or.v8i8(<8 x i8> undef)
+  %V16i8 = call i8 @llvm.vector.reduce.or.v16i8(<16 x i8> undef)
+  %V32i8 = call i8 @llvm.vector.reduce.or.v32i8(<32 x i8> undef)
+  %V64i8 = call i8 @llvm.vector.reduce.or.v64i8(<64 x i8> undef)
+  %V4i16 = call i16 @llvm.vector.reduce.or.v4i16(<4 x i16> undef)
+  %V8i16 = call i16 @llvm.vector.reduce.or.v8i16(<8 x i16> undef)
+  %V16i16 = call i16 @llvm.vector.reduce.or.v16i16(<16 x i16> undef)
+  %V4i32 = call i32 @llvm.vector.reduce.or.v4i32(<4 x i32> undef)
+  %V8i32 = call i32 @llvm.vector.reduce.or.v8i32(<8 x i32> undef)
+  %V2i64 = call i64 @llvm.vector.reduce.or.v2i64(<2 x i64> undef)
+  %V4i64 = call i64 @llvm.vector.reduce.or.v4i64(<4 x i64> undef)
   ret i32 undef
 }

 declare i1 @llvm.vector.reduce.or.v1i1(<1 x i1>)
 declare i1 @llvm.vector.reduce.or.v2i1(<2 x i1>)
 declare i1 @llvm.vector.reduce.or.v4i1(<4 x i1>)
@@ -32,3 +62,17 @@
 declare i1 @llvm.vector.reduce.or.v32i1(<32 x i1>)
 declare i1 @llvm.vector.reduce.or.v64i1(<64 x i1>)
 declare i1 @llvm.vector.reduce.or.v128i1(<128 x i1>)
+declare i8 @llvm.vector.reduce.or.v1i8(<1 x i8>)
+declare i8 @llvm.vector.reduce.or.v3i8(<3 x i8>)
+declare i8 @llvm.vector.reduce.or.v4i8(<4 x i8>)
+declare i8 @llvm.vector.reduce.or.v8i8(<8 x i8>)
+declare i8 @llvm.vector.reduce.or.v16i8(<16 x i8>)
+declare i8 @llvm.vector.reduce.or.v32i8(<32 x i8>)
+declare i8 @llvm.vector.reduce.or.v64i8(<64 x i8>)
+declare i16 @llvm.vector.reduce.or.v4i16(<4 x i16>)
+declare i16 @llvm.vector.reduce.or.v8i16(<8 x i16>)
+declare i16 @llvm.vector.reduce.or.v16i16(<16 x i16>)
+declare i32 @llvm.vector.reduce.or.v4i32(<4 x i32>)
+declare i32 @llvm.vector.reduce.or.v8i32(<8 x i32>)
+declare i64 @llvm.vector.reduce.or.v2i64(<2 x i64>)
+declare i64 @llvm.vector.reduce.or.v4i64(<4 x i64>)