[RISCV] Fold vector binary operatrion into select with identity constant.

[jacquesguan]

Summary

This patch implements shouldFoldSelectWithIdentityConstant for RISCV. It would try to generate vmerge after the binary instruction and let them folded to maksed instruction later.

[craig.topper]

We've been discussing doing this as a post isel peephole or a DAG combine in D130442. That should have much less impact on the size of the generated isel table.

It might not be a good idea to do this fold without checking that the select is the only user of binary op. If it's not the only user you'll duplicate the binary op and there will be a masked and unmasked version. This can increase register pressure and use more execution resources.

[jacquesguan]

Use DAG combiner instead of pattern.

[jacquesguan]

remove empty line.

[jacquesguan]

In D131551#3713084, @craig.topper wrote:

We've been discussing doing this as a post isel peephole or a DAG combine in D130442. That should have much less impact on the size of the generated isel table.

It might not be a good idea to do this fold without checking that the select is the only user of binary op. If it's not the only user you'll duplicate the binary op and there will be a masked and unmasked version. This can increase register pressure and use more execution resources.

Thanks for your advice, I swtich to the DAG combiner. And I do not support fixed vector in this revision as I have not finished its test cases. I will add anothe revision to make it.

[StephenFan]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

8212

Is it possible to use a macro definition to reduce code lines?

[jacquesguan]

Address comment.

[jacquesguan]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

8212

Done.

[jrtc27]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

8169

Why the blank line when the others don't have one?

8209

Imm isn't that clear, this is really the identity

8212

Undefine helper macros like this once you're done with them

[jacquesguan]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

8209

Which word you suggest to use?

[craig.topper]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

1016

Why !hasStdExtZbb()?

8242

VLMaxSentinel is not to be used in SelectionDAG anymore. Use getRegister(RISCV::X0

[craig.topper]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

8185

std::swap?

8219

Some of these operations aren't commutable. If the select is on the LHS of the SUB this transform isn't valid.

8225

1 is not an identity value for urem or srem, it would always return 0.

[craig.topper]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

8221

1 is also not the identify value for MULHS/MULHU. This returns the high half of the product. MULHU(a, 1) produces 0 since the high product is 0. MULHS(a, 1) is a vector filled with the sigh bit of a.

[jacquesguan]

Address comment.

[jacquesguan]

Remove blank line.

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

1016

if (Subtarget.hasStdExtZbb())
  setTargetDAGCombine({ISD::UMAX, ISD::UMIN, ISD::SMAX, ISD::SMIN});

Because if we have Zbb, we already set ISD::UMIN and ISD::UMAX.

8169

Done.

8185

Done.

8212

Done.

8219

Done.

8221

Done, I removed MULHS, MULHU, UREM and SREM.

8225

Done.

8242

Done.

[reames]

Can you land the tests and rebase this change please? Be helpful to see the deltas.

Please also add tests (for only one op flavor is fine) for binop with multiple uses, and other negative edge cases.

[craig.topper]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

1016

It's harmless to do it again and would make the code less confusing.

8171

This isn't protected against illegal types. DAGCombiners can see any types.

My suggestion is to defer this combine until DCI.isAfterLegalizeDAG() which ensure types are legalized and that we don't create _VL operations too early.

8182

Imm -> IdentityImm

8189

Use TargetLowering::isCommutativeBinOp?

8229

Technically you need to truncate the splat_vector input to element size. But maybe all your tests are before type legalization so you don't test any SPLAT_VECTORS where the scalar input is larger than the element type?

8233

VMV_V_X_VL is allowed to have scalar values both larger and smaller than the element type.

[jacquesguan]

Address comment.

[jacquesguan]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

1016

Done.

8171

Done.

8182

Done.

8189

Done.

8229

Done.

8233

Done.

[jacquesguan]

In D131551#3723187, @reames wrote:

Can you land the tests and rebase this change please? Be helpful to see the deltas.

Please also add tests (for only one op flavor is fine) for binop with multiple uses, and other negative edge cases.

Done, I add a pre-commit test in https://reviews.llvm.org/D131950, and the negative test is added in the llvm/test/CodeGen/RISCV/rvv/vadd-sdnode.ll.

[jacquesguan]

ping.

[craig.topper]

How much does this overlap with implementing RISCVTargetLowering::shouldFoldSelectWithIdentityConstant and letting the generic DAGCombiner do this?

[jacquesguan]

In D131551#3756737, @craig.topper wrote:

How much does this overlap with implementing RISCVTargetLowering::shouldFoldSelectWithIdentityConstant and letting the generic DAGCombiner do this?

Thanks, it should work, but I need https://reviews.llvm.org/D132923 to fold the transformed DAG, could you mind to have a review?

[jacquesguan]

Use RISCVTargetLowering::shouldFoldSelectWithIdentityConstant to make it.

[jacquesguan]

In D131551#3756737, @craig.topper wrote:

How much does this overlap with implementing RISCVTargetLowering::shouldFoldSelectWithIdentityConstant and letting the generic DAGCombiner do this?

Done.

[jacquesguan]

ping.

[craig.topper]

foldSelectWithIdentityConstant handles FP as well, but you have no FP tests. It doesn't look like you did anything to disable FP unless I missed it.

llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

2220 ↗

(On Diff #461806)

This needs to be rebased.

[jacquesguan]

rebase and add fp test.

[jacquesguan]

In D131551#3869552, @craig.topper wrote:

foldSelectWithIdentityConstant handles FP as well, but you have no FP tests. It doesn't look like you did anything to disable FP unless I missed it.

Done, I add FP cases.

llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

2220 ↗

(On Diff #461806)

Done.

[jacquesguan]

ping.

[jacquesguan]

ping.

[craig.topper]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

1236

This is imprecise for FP which has a different ELEN for Zve64f and Zve32x.

I think you can ignore it for scalable vectors since those elements always have to be supported if we see them. For fixed vectors we should check isTypeLegal.

[jacquesguan]

Address comment.

[jacquesguan]

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

1236

Done, thanks.

[jacquesguan]

ping.

[craig.topper]

LGTM

llvm/lib/Target/RISCV/RISCVISelLowering.h

MVT getRegisterTypeForCallingConv(LLVMContext &Context, CallingConv::ID CC,
                                     EVT VT) const override;
 
   /// Return the number of registers for a given MVT, ensuring vectors are
   /// treated as a series of gpr sized integers.
   unsigned getNumRegistersForCallingConv(LLVMContext &Context,
                                          CallingConv::ID CC,
                                          EVT VT) const override;
 
+  bool shouldFoldSelectWithIdentityConstant(unsigned BinOpcode,
+                                            EVT VT) const override;
+
   /// Return true if the given shuffle mask can be codegen'd directly, or if it
   /// should be stack expanded.
   bool isShuffleMaskLegal(ArrayRef<int> M, EVT VT) const override;
 
   bool hasBitPreservingFPLogic(EVT VT) const override;
   bool
   shouldExpandBuildVectorWithShuffles(EVT VT,
                                       unsigned DefinedValues) const override;

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

if (Subtarget.hasStdExtF())
     setTargetDAGCombine({ISD::ZERO_EXTEND, ISD::FP_TO_SINT, ISD::FP_TO_UINT,
                          ISD::FP_TO_SINT_SAT, ISD::FP_TO_UINT_SAT});
   if (Subtarget.hasVInstructions())
     setTargetDAGCombine({ISD::FCOPYSIGN, ISD::MGATHER, ISD::MSCATTER,
                          ISD::VP_GATHER, ISD::VP_SCATTER, ISD::SRA, ISD::SRL,
                          ISD::SHL, ISD::STORE, ISD::SPLAT_VECTOR});
   if (Subtarget.useRVVForFixedLengthVectors())
     setTargetDAGCombine(ISD::BITCAST);
 
   setLibcallName(RTLIB::FPEXT_F16_F32, "__extendhfsf2");
   setLibcallName(RTLIB::FPROUND_F32_F16, "__truncsfhf2");
 }
 
 EVT RISCVTargetLowering::getSetCCResultType(const DataLayout &DL,
                                             LLVMContext &Context,
                                             EVT VT) const {
   if (!VT.isVector())
bool RISCVTargetLowering::hasBitTest(SDValue X, SDValue Y) const {
   // Zbs provides BEXT[_I], which can be used with SEQZ/SNEZ as a bit test.
   if (Subtarget.hasStdExtZbs())
     return X.getValueType().isScalarInteger();
   // We can use ANDI+SEQZ/SNEZ as a bit test. Y contains the bit position.
   auto *C = dyn_cast<ConstantSDNode>(Y);
   return C && C->getAPIntValue().ule(10);
 }
 
+bool RISCVTargetLowering::shouldFoldSelectWithIdentityConstant(unsigned Opcode,
+                                                               EVT VT) const {
+  // Only enable for rvv.
+  if (!VT.isVector() || !Subtarget.hasVInstructions())
+    return false;
+
+  if (VT.isFixedLengthVector() && !isTypeLegal(VT))
+    return false;
+
+  return true;
+}
+
 bool RISCVTargetLowering::shouldConvertConstantLoadToIntImm(const APInt &Imm,
                                                             Type *Ty) const {
   assert(Ty->isIntegerTy());
 
   unsigned BitSize = Ty->getIntegerBitWidth();
   if (BitSize > Subtarget.getXLen())
     return false;
 
SDValue New1 =
       DAG.getNode(ISD::MUL, DL, VT, New0, DAG.getConstant(C0, DL, VT));
   return DAG.getNode(ISD::ADD, DL, VT, New1, DAG.getConstant(CB, DL, VT));
 }
 
 static SDValue performADDCombine(SDNode *N, SelectionDAG &DAG,
                                  const RISCVSubtarget &Subtarget) {
   if (SDValue V = transformAddImmMulImm(N, DAG, Subtarget))
     return V;
   if (SDValue V = transformAddShlImm(N, DAG, Subtarget))
     return V;
   if (SDValue V = combineBinOpToReduce(N, DAG))
     return V;
   // fold (add (select lhs, rhs, cc, 0, y), x) ->
   //      (select lhs, rhs, cc, x, (add x, y))
   return combineSelectAndUseCommutative(N, DAG, /*AllOnes*/ false);
 }
 
 // Try to turn a sub boolean RHS and constant LHS into an addi.
 static SDValue combineSubOfBoolean(SDNode *N, SelectionDAG &DAG) {
   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   EVT VT = N->getValueType(0);
   SDLoc DL(N);
 
   // Require a constant LHS.
   auto *N0C = dyn_cast<ConstantSDNode>(N0);
   if (!N0C)
     return SDValue();
 
   // All our optimizations involve subtracting 1 from the immediate and forming
   // an ADDI. Make sure the new immediate is valid for an ADDI.
   APInt ImmValMinus1 = N0C->getAPIntValue() - 1;
   if (!ImmValMinus1.isSignedIntN(12))
     return SDValue();
 
   SDValue NewLHS;
   if (N1.getOpcode() == ISD::SETCC && N1.hasOneUse()) {
     // (sub constant, (setcc x, y, eq/neq)) ->
     // (add (setcc x, y, neq/eq), constant - 1)
     ISD::CondCode CCVal = cast<CondCodeSDNode>(N1.getOperand(2))->get();
     EVT SetCCOpVT = N1.getOperand(0).getValueType();
     if (!isIntEqualitySetCC(CCVal) || !SetCCOpVT.isInteger())
       return SDValue();
     CCVal = ISD::getSetCCInverse(CCVal, SetCCOpVT);
     NewLHS =
         DAG.getSetCC(SDLoc(N1), VT, N1.getOperand(0), N1.getOperand(1), CCVal);
   } else if (N1.getOpcode() == ISD::XOR && isOneConstant(N1.getOperand(1)) &&
              N1.getOperand(0).getOpcode() == ISD::SETCC) {
     // (sub C, (xor (setcc), 1)) -> (add (setcc), C-1).
     // Since setcc returns a bool the xor is equivalent to 1-setcc.
     NewLHS = N1.getOperand(0);
   } else
     return SDValue();
 
   SDValue NewRHS = DAG.getConstant(ImmValMinus1, DL, VT);
   return DAG.getNode(ISD::ADD, DL, VT, NewLHS, NewRHS);
 }
 
 static SDValue performSUBCombine(SDNode *N, SelectionDAG &DAG) {
   if (SDValue V = combineSubOfBoolean(N, DAG))
     return V;
 
   // fold (sub x, (select lhs, rhs, cc, 0, y)) ->
   //      (select lhs, rhs, cc, x, (sub x, y))
   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   return combineSelectAndUse(N, N1, N0, DAG, /*AllOnes*/ false);
 }
 
 // Apply DeMorgan's law to (and/or (xor X, 1), (xor Y, 1)) if X and Y are 0/1.
 // Legalizing setcc can introduce xors like this. Doing this transform reduces
 // the number of xors and may allow the xor to fold into a branch condition.
 static SDValue combineDeMorganOfBoolean(SDNode *N, SelectionDAG &DAG) {
   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   bool IsAnd = N->getOpcode() == ISD::AND;
 
   if (N0.getOpcode() != ISD::XOR || N1.getOpcode() != ISD::XOR)
     return SDValue();
 
   if (!N0.hasOneUse() || !N1.hasOneUse())
     return SDValue();
 
   SDValue N01 = N0.getOperand(1);
   SDValue N11 = N1.getOperand(1);
 
   // For AND, SimplifyDemandedBits may have turned one of the (xor X, 1) into
   // (xor X, -1) based on the upper bits of the other operand being 0. If the
   // operation is And, allow one of the Xors to use -1.
   if (isOneConstant(N01)) {

llvm/test/CodeGen/RISCV/rvv/vadd-sdnode.ll

; RV64-NEXT:    ret
   %splat2 = shufflevector <vscale x 8 x i64> %head2, <vscale x 8 x i64> poison, <vscale x 8 x i32> zeroinitializer
   %v = add <vscale x 8 x i64> %splat1, %splat2
   ret <vscale x 8 x i64> %v
 }
 
 define <vscale x 8 x i32> @vadd_vv_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i32> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vadd_vv_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 0
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vadd.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vadd.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %vb, <vscale x 8 x i32> zeroinitializer
   %vc = add <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vadd_vx_mask_nxv8i32(<vscale x 8 x i32> %va, i32 signext %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vadd_vx_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vadd.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vadd.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 %b, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = add <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vadd_vi_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vadd_vi_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vim v12, v12, 7, v0
-; CHECK-NEXT:    vadd.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vadd.vi v8, v8, 7, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 7, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = add <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 

llvm/test/CodeGen/RISCV/rvv/vand-sdnode.ll

; RV64-NEXT:    ret
   %splat2 = shufflevector <vscale x 8 x i64> %head2, <vscale x 8 x i64> poison, <vscale x 8 x i32> zeroinitializer
   %v = and <vscale x 8 x i64> %splat1, %splat2
   ret <vscale x 8 x i64> %v
 }
 
 define <vscale x 8 x i32> @vand_vv_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i32> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vand_vv_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, -1
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vand.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vand.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 -1, i32 0
   %allones = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %vb, <vscale x 8 x i32> %allones
   %vc = and <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vand_vx_mask_nxv8i32(<vscale x 8 x i32> %va, i32 signext %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vand_vx_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, -1
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vand.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vand.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head1 = insertelement <vscale x 8 x i32> poison, i32 -1, i32 0
   %allones = shufflevector <vscale x 8 x i32> %head1, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %head2 = insertelement <vscale x 8 x i32> poison, i32 %b, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head2, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> %allones
   %vc = and <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vand_vi_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vand_vi_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, -1
-; CHECK-NEXT:    vmerge.vim v12, v12, 7, v0
-; CHECK-NEXT:    vand.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vand.vi v8, v8, 7, v0.t
 ; CHECK-NEXT:    ret
   %head1 = insertelement <vscale x 8 x i32> poison, i32 -1, i32 0
   %allones = shufflevector <vscale x 8 x i32> %head1, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %head2 = insertelement <vscale x 8 x i32> poison, i32 7, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head2, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> %allones
   %vc = and <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }

llvm/test/CodeGen/RISCV/rvv/vfadd-sdnode.ll

; CHECK-NEXT:    ret
   %splat = shufflevector <vscale x 8 x double> %head, <vscale x 8 x double> poison, <vscale x 8 x i32> zeroinitializer
   %vc = fadd <vscale x 8 x double> %splat, %va
   ret <vscale x 8 x double> %vc
 }
 
 define <vscale x 8 x float> @vfadd_vv_mask_nxv8f32(<vscale x 8 x float> %va, <vscale x 8 x float> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vfadd_vv_mask_nxv8f32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 0
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vfadd.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vfadd.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x float> poison, float 0.0, i32 0
   %splat = shufflevector <vscale x 8 x float> %head, <vscale x 8 x float> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x float> %vb, <vscale x 8 x float> %splat
   %vc = fadd fast <vscale x 8 x float> %va, %vs
   ret <vscale x 8 x float> %vc
 }
 
 define <vscale x 8 x float> @vfadd_vf_mask_nxv8f32(<vscale x 8 x float> %va, float %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vfadd_vf_mask_nxv8f32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vfmerge.vfm v12, v12, fa0, v0
-; CHECK-NEXT:    vfadd.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vfadd.vf v8, v8, fa0, v0.t
 ; CHECK-NEXT:    ret
   %head0 = insertelement <vscale x 8 x float> poison, float 0.0, i32 0
   %splat0 = shufflevector <vscale x 8 x float> %head0, <vscale x 8 x float> poison, <vscale x 8 x i32> zeroinitializer
   %head1 = insertelement <vscale x 8 x float> poison, float %b, i32 0
   %splat1 = shufflevector <vscale x 8 x float> %head1, <vscale x 8 x float> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x float> %splat1, <vscale x 8 x float> %splat0
   %vc = fadd fast <vscale x 8 x float> %va, %vs
   ret <vscale x 8 x float> %vc
 }

llvm/test/CodeGen/RISCV/rvv/vfsub-sdnode.ll

; CHECK-NEXT:    ret
   %splat = shufflevector <vscale x 8 x double> %head, <vscale x 8 x double> poison, <vscale x 8 x i32> zeroinitializer
   %vc = fsub <vscale x 8 x double> %splat, %va
   ret <vscale x 8 x double> %vc
 }
 
 define <vscale x 8 x float> @vfsub_vv_mask_nxv8f32(<vscale x 8 x float> %va, <vscale x 8 x float> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vfsub_vv_mask_nxv8f32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 0
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vfsub.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vfsub.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x float> poison, float 0.0, i32 0
   %splat = shufflevector <vscale x 8 x float> %head, <vscale x 8 x float> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x float> %vb, <vscale x 8 x float> %splat
   %vc = fsub fast <vscale x 8 x float> %va, %vs
   ret <vscale x 8 x float> %vc
 }
 
 define <vscale x 8 x float> @vfsub_vf_mask_nxv8f32(<vscale x 8 x float> %va, float %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vfsub_vf_mask_nxv8f32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vfmerge.vfm v12, v12, fa0, v0
-; CHECK-NEXT:    vfsub.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vfsub.vf v8, v8, fa0, v0.t
 ; CHECK-NEXT:    ret
   %head0 = insertelement <vscale x 8 x float> poison, float 0.0, i32 0
   %splat0 = shufflevector <vscale x 8 x float> %head0, <vscale x 8 x float> poison, <vscale x 8 x i32> zeroinitializer
   %head1 = insertelement <vscale x 8 x float> poison, float %b, i32 0
   %splat1 = shufflevector <vscale x 8 x float> %head1, <vscale x 8 x float> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x float> %splat1, <vscale x 8 x float> %splat0
   %vc = fsub fast <vscale x 8 x float> %va, %vs
   ret <vscale x 8 x float> %vc
 }

llvm/test/CodeGen/RISCV/rvv/vmul-sdnode.ll

; RV64M-NEXT:    ret
   %splat2 = shufflevector <vscale x 8 x i64> %head2, <vscale x 8 x i64> poison, <vscale x 8 x i32> zeroinitializer
   %v = mul <vscale x 8 x i64> %splat1, %splat2
   ret <vscale x 8 x i64> %v
 }
 
 define <vscale x 8 x i32> @vmul_vv_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i32> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vmul_vv_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 1
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vmul.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vmul.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 1, i32 0
   %one = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %vb, <vscale x 8 x i32> %one
   %vc = mul <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vmul_vx_mask_nxv8i32(<vscale x 8 x i32> %va, i32 signext %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vmul_vx_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 1
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vmul.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vmul.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head1 = insertelement <vscale x 8 x i32> poison, i32 1, i32 0
   %one = shufflevector <vscale x 8 x i32> %head1, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %head2 = insertelement <vscale x 8 x i32> poison, i32 %b, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head2, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> %one
   %vc = mul <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vmul_vi_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vmul_vi_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 1
-; CHECK-NEXT:    vmerge.vim v12, v12, 7, v0
-; CHECK-NEXT:    vmul.vv v8, v8, v12
+; CHECK-NEXT:    li a0, 7
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vmul.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head1 = insertelement <vscale x 8 x i32> poison, i32 1, i32 0
   %one = shufflevector <vscale x 8 x i32> %head1, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %head2 = insertelement <vscale x 8 x i32> poison, i32 7, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head2, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> %one
   %vc = mul <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 

llvm/test/CodeGen/RISCV/rvv/vor-sdnode.ll

; RV64-NEXT:    ret
   %splat2 = shufflevector <vscale x 8 x i64> %head2, <vscale x 8 x i64> poison, <vscale x 8 x i32> zeroinitializer
   %v = or <vscale x 8 x i64> %splat1, %splat2
   ret <vscale x 8 x i64> %v
 }
 
 define <vscale x 8 x i32> @vor_vv_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i32> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vor_vv_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 0
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vor.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vor.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %vb, <vscale x 8 x i32> zeroinitializer
   %vc = or <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vor_vx_mask_nxv8i32(<vscale x 8 x i32> %va, i32 signext %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vor_vx_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vor.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vor.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 %b, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = or <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vor_vi_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vor_vi_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vim v12, v12, 7, v0
-; CHECK-NEXT:    vor.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vor.vi v8, v8, 7, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 7, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = or <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }

llvm/test/CodeGen/RISCV/rvv/vshl-sdnode.ll

; CHECK-NEXT:    ret
   %splat = shufflevector <vscale x 8 x i64> %head, <vscale x 8 x i64> poison, <vscale x 8 x i32> zeroinitializer
   %vc = shl <vscale x 8 x i64> %va, %splat
   ret <vscale x 8 x i64> %vc
 }
 
 define <vscale x 8 x i32> @vshl_vv_mask_nxv4i32(<vscale x 8 x i32> %va, <vscale x 8 x i32> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vshl_vv_mask_nxv4i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 0
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vsll.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsll.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %vb, <vscale x 8 x i32> zeroinitializer
   %vc = shl <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vshl_vx_mask_nxv8i32(<vscale x 8 x i32> %va, i32 signext %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vshl_vx_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vsll.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsll.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 %b, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = shl <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vshl_vi_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vshl_vi_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    li a0, 31
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vsll.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsll.vi v8, v8, 31, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 31, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = shl <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }

llvm/test/CodeGen/RISCV/rvv/vsra-sdnode.ll

; CHECK-NEXT:    ret
   %splat = shufflevector <vscale x 8 x i64> %head, <vscale x 8 x i64> poison, <vscale x 8 x i32> zeroinitializer
   %vc = ashr <vscale x 8 x i64> %va, %splat
   ret <vscale x 8 x i64> %vc
 }
 
 define <vscale x 8 x i32> @vsra_vv_mask_nxv4i32(<vscale x 8 x i32> %va, <vscale x 8 x i32> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vsra_vv_mask_nxv4i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 0
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vsra.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsra.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %vb, <vscale x 8 x i32> zeroinitializer
   %vc = ashr <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vsra_vx_mask_nxv8i32(<vscale x 8 x i32> %va, i32 signext %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vsra_vx_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vsra.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsra.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 %b, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = ashr <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vsra_vi_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vsra_vi_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    li a0, 31
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vsra.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsra.vi v8, v8, 31, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 31, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = ashr <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }

llvm/test/CodeGen/RISCV/rvv/vsrl-sdnode.ll

; CHECK-NEXT:    ret
   %splat = shufflevector <vscale x 8 x i64> %head, <vscale x 8 x i64> poison, <vscale x 8 x i32> zeroinitializer
   %vc = lshr <vscale x 8 x i64> %va, %splat
   ret <vscale x 8 x i64> %vc
 }
 
 define <vscale x 8 x i32> @vsrl_vv_mask_nxv4i32(<vscale x 8 x i32> %va, <vscale x 8 x i32> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vsrl_vv_mask_nxv4i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 0
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vsrl.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsrl.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %vb, <vscale x 8 x i32> zeroinitializer
   %vc = lshr <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vsrl_vx_mask_nxv8i32(<vscale x 8 x i32> %va, i32 signext %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vsrl_vx_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vsrl.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsrl.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 %b, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = lshr <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vsrl_vi_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vsrl_vi_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    li a0, 31
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vsrl.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsrl.vi v8, v8, 31, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 31, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = lshr <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }

llvm/test/CodeGen/RISCV/rvv/vsub-sdnode.ll

; RV64-NEXT:    ret
   %splat2 = shufflevector <vscale x 8 x i64> %head2, <vscale x 8 x i64> poison, <vscale x 8 x i32> zeroinitializer
   %v = sub <vscale x 8 x i64> %splat1, %splat2
   ret <vscale x 8 x i64> %v
 }
 
 define <vscale x 8 x i32> @vsub_vv_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i32> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vsub_vv_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 0
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vsub.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsub.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
 
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %vb, <vscale x 8 x i32> zeroinitializer
   %vc = sub <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vsub_vx_mask_nxv8i32(<vscale x 8 x i32> %va, i32 signext %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vsub_vx_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vsub.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsub.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 %b, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = sub <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vsub_vi_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vsub_vi_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vim v12, v12, 7, v0
-; CHECK-NEXT:    vsub.vv v8, v8, v12
+; CHECK-NEXT:    li a0, 7
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vsub.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 7, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = sub <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }

llvm/test/CodeGen/RISCV/rvv/vxor-sdnode.ll

; RV64-NEXT:    ret
   %splat2 = shufflevector <vscale x 8 x i64> %head2, <vscale x 8 x i64> poison, <vscale x 8 x i32> zeroinitializer
   %v = xor <vscale x 8 x i64> %splat1, %splat2
   ret <vscale x 8 x i64> %v
 }
 
 define <vscale x 8 x i32> @vxor_vv_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i32> %vb, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vxor_vv_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v16, 0
-; CHECK-NEXT:    vmerge.vvm v12, v16, v12, v0
-; CHECK-NEXT:    vxor.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vxor.vv v8, v8, v12, v0.t
 ; CHECK-NEXT:    ret
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %vb, <vscale x 8 x i32> zeroinitializer
   %vc = xor <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vxor_vx_mask_nxv8i32(<vscale x 8 x i32> %va, i32 signext %b, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vxor_vx_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vxm v12, v12, a0, v0
-; CHECK-NEXT:    vxor.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a1, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vxor.vx v8, v8, a0, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 %b, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = xor <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }
 
 define <vscale x 8 x i32> @vxor_vi_mask_nxv8i32(<vscale x 8 x i32> %va, <vscale x 8 x i1> %mask) {
 ; CHECK-LABEL: vxor_vi_mask_nxv8i32:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, ma
-; CHECK-NEXT:    vmv.v.i v12, 0
-; CHECK-NEXT:    vmerge.vim v12, v12, 7, v0
-; CHECK-NEXT:    vxor.vv v8, v8, v12
+; CHECK-NEXT:    vsetvli a0, zero, e32, m4, ta, mu
+; CHECK-NEXT:    vxor.vi v8, v8, 7, v0.t
 ; CHECK-NEXT:    ret
   %head = insertelement <vscale x 8 x i32> poison, i32 7, i32 0
   %splat = shufflevector <vscale x 8 x i32> %head, <vscale x 8 x i32> poison, <vscale x 8 x i32> zeroinitializer
   %vs = select <vscale x 8 x i1> %mask, <vscale x 8 x i32> %splat, <vscale x 8 x i32> zeroinitializer
   %vc = xor <vscale x 8 x i32> %va, %vs
   ret <vscale x 8 x i32> %vc
 }