diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 675a230bd2c94..af5273bd210d3 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -7949,6 +7949,7 @@ VPWidenRecipe *VPRecipeBuilder::tryToWiden(Instruction *I,
       VPValue *One =
           Plan.getOrAddLiveIn(ConstantInt::get(I->getType(), 1u, false));
       auto *SafeRHS = Builder.createSelect(Mask, Ops[1], One, I->getDebugLoc());
+      SafeRHS->setUnderlyingValue(I);
       Ops[1] = SafeRHS;
       return new VPWidenRecipe(*I, Ops);
     }
diff --git a/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp b/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
index fa62547d374cd..da11f922b5362 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
@@ -972,6 +972,19 @@ InstructionCost VPInstruction::computeCost(ElementCount VF,
     return Ctx.TTI.getVectorInstrCost(Instruction::ExtractElement, VecTy,
                                       Ctx.CostKind);
   }
+  case Instruction::Select: {
+    // TODO: Compute cost for VPInstructions without underlying values once
+    // the legacy cost model has been retired.
+    if (!getUnderlyingValue())
+      return 0;
+    Type *ResTy = Ctx.Types.inferScalarType(this);
+    if (!vputils::onlyFirstLaneUsed(this))
+      ResTy = toVectorTy(ResTy, VF);
+    return Ctx.TTI.getCmpSelInstrCost(
+        Instruction::Select, ResTy,
+        ResTy->getWithNewType(Type::getInt1Ty(ResTy->getContext())),
+        CmpInst::BAD_ICMP_PREDICATE, Ctx.CostKind);
+  }
   case VPInstruction::AnyOf: {
     auto *VecTy = toVectorTy(Ctx.Types.inferScalarType(this), VF);
     return Ctx.TTI.getArithmeticReductionCost(
@@ -2037,8 +2050,6 @@ InstructionCost VPWidenRecipe::computeCost(ElementCount VF,
   case Instruction::SDiv:
   case Instruction::SRem:
   case Instruction::URem:
-    // More complex computation, let the legacy cost-model handle this for now.
-    return Ctx.getLegacyCost(cast<Instruction>(getUnderlyingValue()), VF);
   case Instruction::Add:
   case Instruction::FAdd:
   case Instruction::Sub:
diff --git a/llvm/test/Transforms/LoopVectorize/RISCV/pr154103.ll b/llvm/test/Transforms/LoopVectorize/RISCV/pr154103.ll
new file mode 100644
index 0000000000000..d4b3cfffa4501
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/RISCV/pr154103.ll
@@ -0,0 +1,108 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 5
+; RUN: opt -p loop-vectorize -mtriple riscv64 -mattr=+v < %s -S | FileCheck %s
+
+define void @pr154103(ptr noalias %a, ptr noalias %b, ptr noalias %c, ptr noalias %d) {
+; CHECK-LABEL: define void @pr154103(
+; CHECK-SAME: ptr noalias [[A:%.*]], ptr noalias [[B:%.*]], ptr noalias [[C:%.*]], ptr noalias [[D:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    br i1 false, label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <vscale x 4 x ptr> poison, ptr [[B]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <vscale x 4 x ptr> [[BROADCAST_SPLATINSERT]], <vscale x 4 x ptr> poison, <vscale x 4 x i32> zeroinitializer
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <vscale x 4 x ptr> poison, ptr [[C]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT2:%.*]] = shufflevector <vscale x 4 x ptr> [[BROADCAST_SPLATINSERT1]], <vscale x 4 x ptr> poison, <vscale x 4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP0:%.*]] = call <vscale x 4 x i64> @llvm.stepvector.nxv4i64()
+; CHECK-NEXT:    [[TMP1:%.*]] = mul <vscale x 4 x i64> [[TMP0]], splat (i64 7)
+; CHECK-NEXT:    [[INDUCTION:%.*]] = add <vscale x 4 x i64> splat (i64 1), [[TMP1]]
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[EVL_BASED_IV:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_EVL_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <vscale x 4 x i64> [ [[INDUCTION]], %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[AVL:%.*]] = phi i64 [ -7905747460161236406, %[[VECTOR_PH]] ], [ [[AVL_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[TMP2:%.*]] = call i32 @llvm.experimental.get.vector.length.i64(i64 [[AVL]], i32 4, i1 true)
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT5:%.*]] = insertelement <vscale x 4 x i32> poison, i32 [[TMP2]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT6:%.*]] = shufflevector <vscale x 4 x i32> [[BROADCAST_SPLATINSERT5]], <vscale x 4 x i32> poison, <vscale x 4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP3:%.*]] = zext i32 [[TMP2]] to i64
+; CHECK-NEXT:    [[TMP4:%.*]] = mul i64 7, [[TMP3]]
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT3:%.*]] = insertelement <vscale x 4 x i64> poison, i64 [[TMP4]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT4:%.*]] = shufflevector <vscale x 4 x i64> [[BROADCAST_SPLATINSERT3]], <vscale x 4 x i64> poison, <vscale x 4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP5:%.*]] = call <vscale x 4 x i32> @llvm.stepvector.nxv4i32()
+; CHECK-NEXT:    [[TMP6:%.*]] = icmp ult <vscale x 4 x i32> [[TMP5]], [[BROADCAST_SPLAT6]]
+; CHECK-NEXT:    [[TMP7:%.*]] = getelementptr i8, ptr [[A]], <vscale x 4 x i64> [[VEC_IND]]
+; CHECK-NEXT:    [[WIDE_MASKED_GATHER:%.*]] = call <vscale x 4 x i8> @llvm.vp.gather.nxv4i8.nxv4p0(<vscale x 4 x ptr> align 1 [[TMP7]], <vscale x 4 x i1> splat (i1 true), i32 [[TMP2]])
+; CHECK-NEXT:    [[TMP8:%.*]] = zext <vscale x 4 x i8> [[WIDE_MASKED_GATHER]] to <vscale x 4 x i64>
+; CHECK-NEXT:    [[TMP9:%.*]] = call <vscale x 4 x i64> @llvm.vp.merge.nxv4i64(<vscale x 4 x i1> splat (i1 true), <vscale x 4 x i64> [[TMP8]], <vscale x 4 x i64> splat (i64 1), i32 [[TMP2]])
+; CHECK-NEXT:    [[TMP10:%.*]] = sdiv <vscale x 4 x i64> zeroinitializer, [[TMP9]]
+; CHECK-NEXT:    [[TMP11:%.*]] = icmp sgt <vscale x 4 x i64> [[TMP10]], zeroinitializer
+; CHECK-NEXT:    [[TMP12:%.*]] = select <vscale x 4 x i1> [[TMP6]], <vscale x 4 x i1> [[TMP11]], <vscale x 4 x i1> zeroinitializer
+; CHECK-NEXT:    [[WIDE_MASKED_GATHER7:%.*]] = call <vscale x 4 x i8> @llvm.vp.gather.nxv4i8.nxv4p0(<vscale x 4 x ptr> align 1 [[BROADCAST_SPLAT]], <vscale x 4 x i1> [[TMP11]], i32 [[TMP2]])
+; CHECK-NEXT:    [[TMP13:%.*]] = zext <vscale x 4 x i8> [[WIDE_MASKED_GATHER7]] to <vscale x 4 x i64>
+; CHECK-NEXT:    [[TMP14:%.*]] = xor <vscale x 4 x i64> [[TMP13]], zeroinitializer
+; CHECK-NEXT:    [[PREDPHI:%.*]] = select <vscale x 4 x i1> [[TMP12]], <vscale x 4 x i64> [[TMP14]], <vscale x 4 x i64> zeroinitializer
+; CHECK-NEXT:    [[TMP15:%.*]] = trunc <vscale x 4 x i64> [[PREDPHI]] to <vscale x 4 x i16>
+; CHECK-NEXT:    call void @llvm.vp.scatter.nxv4i16.nxv4p0(<vscale x 4 x i16> [[TMP15]], <vscale x 4 x ptr> align 2 [[BROADCAST_SPLAT2]], <vscale x 4 x i1> splat (i1 true), i32 [[TMP2]])
+; CHECK-NEXT:    store i32 0, ptr [[D]], align 4
+; CHECK-NEXT:    [[TMP16:%.*]] = zext i32 [[TMP2]] to i64
+; CHECK-NEXT:    [[INDEX_EVL_NEXT]] = add i64 [[TMP16]], [[EVL_BASED_IV]]
+; CHECK-NEXT:    [[AVL_NEXT]] = sub nuw i64 [[AVL]], [[TMP16]]
+; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <vscale x 4 x i64> [[VEC_IND]], [[BROADCAST_SPLAT4]]
+; CHECK-NEXT:    [[TMP17:%.*]] = icmp eq i64 [[INDEX_EVL_NEXT]], -7905747460161236406
+; CHECK-NEXT:    br i1 [[TMP17]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    br label %[[EXIT:.*]]
+; CHECK:       [[SCALAR_PH]]:
+; CHECK-NEXT:    br label %[[LOOP:.*]]
+; CHECK:       [[LOOP]]:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 1, %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LATCH:.*]] ]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i8, ptr [[A]], i64 [[IV]]
+; CHECK-NEXT:    [[X:%.*]] = load i8, ptr [[GEP]], align 1
+; CHECK-NEXT:    [[CONV:%.*]] = zext i8 [[X]] to i64
+; CHECK-NEXT:    [[DIV:%.*]] = sdiv i64 0, [[CONV]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i64 [[DIV]], 0
+; CHECK-NEXT:    br i1 [[CMP]], label %[[THEN:.*]], label %[[LATCH]]
+; CHECK:       [[THEN]]:
+; CHECK-NEXT:    [[Y:%.*]] = load i8, ptr [[B]], align 1
+; CHECK-NEXT:    [[ZEXT:%.*]] = zext i8 [[Y]] to i64
+; CHECK-NEXT:    [[NOT:%.*]] = xor i64 [[ZEXT]], 0
+; CHECK-NEXT:    br label %[[LATCH]]
+; CHECK:       [[LATCH]]:
+; CHECK-NEXT:    [[COND:%.*]] = phi i64 [ [[NOT]], %[[THEN]] ], [ 0, %[[LOOP]] ]
+; CHECK-NEXT:    [[TRUNC:%.*]] = trunc i64 [[COND]] to i16
+; CHECK-NEXT:    store i16 [[TRUNC]], ptr [[C]], align 2
+; CHECK-NEXT:    store i32 0, ptr [[D]], align 4
+; CHECK-NEXT:    [[IV_NEXT]] = add i64 [[IV]], 7
+; CHECK-NEXT:    [[DONE:%.*]] = icmp eq i64 [[IV]], 0
+; CHECK-NEXT:    br i1 [[DONE]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK:       [[EXIT]]:
+; CHECK-NEXT:    ret void
+;
+entry:
+  br label %loop
+
+loop:
+  %iv = phi i64 [ 1, %entry ], [ %iv.next, %latch ]
+  %gep = getelementptr i8, ptr %a, i64 %iv
+  %x = load i8, ptr %gep, align 1
+  %conv = zext i8 %x to i64
+  %div = sdiv i64 0, %conv
+  %cmp = icmp sgt i64 %div, 0
+  br i1 %cmp, label %then, label %latch
+
+then:
+  %y = load i8, ptr %b
+  %zext = zext i8 %y to i64
+  %not = xor i64 %zext, 0
+  br label %latch
+
+latch:
+  %cond = phi i64 [ %not, %then ], [ 0, %loop ]
+  %trunc = trunc i64 %cond to i16
+  store i16 %trunc, ptr %c
+  store i32 0, ptr %d
+  %iv.next = add i64 %iv, 7
+  %done = icmp eq i64 %iv, 0
+  br i1 %done, label %exit, label %loop
+
+exit:
+  ret void
+}