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//===-- RISCVISelDAGToDAG.cpp - A dag to dag inst selector for RISCV ------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines an instruction selector for the RISCV target.
//
//===----------------------------------------------------------------------===//
#include "RISCVISelDAGToDAG.h"
#include "MCTargetDesc/RISCVMCTargetDesc.h"
#include "MCTargetDesc/RISCVMatInt.h"
#include "RISCVISelLowering.h"
#include "RISCVMachineFunctionInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/IR/IntrinsicsRISCV.h"
#include "llvm/Support/Alignment.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/KnownBits.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#define DEBUG_TYPE "riscv-isel"
namespace llvm {
namespace RISCV {
#define GET_RISCVVSSEGTable_IMPL
#define GET_RISCVVLSEGTable_IMPL
#define GET_RISCVVLXSEGTable_IMPL
#define GET_RISCVVSXSEGTable_IMPL
#define GET_RISCVVLETable_IMPL
#define GET_RISCVVSETable_IMPL
#define GET_RISCVVLXTable_IMPL
#define GET_RISCVVSXTable_IMPL
#include "RISCVGenSearchableTables.inc"
} // namespace RISCV
} // namespace llvm
void RISCVDAGToDAGISel::PreprocessISelDAG() {
for (SelectionDAG::allnodes_iterator I = CurDAG->allnodes_begin(),
E = CurDAG->allnodes_end();
I != E;) {
SDNode *N = &*I++; // Preincrement iterator to avoid invalidation issues.
// Lower SPLAT_VECTOR_SPLIT_I64 to two scalar stores and a stride 0 vector
// load. Done after lowering and combining so that we have a chance to
// optimize this to VMV_V_X_VL when the upper bits aren't needed.
if (N->getOpcode() != RISCVISD::SPLAT_VECTOR_SPLIT_I64_VL)
continue;
assert(N->getNumOperands() == 3 && "Unexpected number of operands");
MVT VT = N->getSimpleValueType(0);
SDValue Lo = N->getOperand(0);
SDValue Hi = N->getOperand(1);
SDValue VL = N->getOperand(2);
assert(VT.getVectorElementType() == MVT::i64 && VT.isScalableVector() &&
Lo.getValueType() == MVT::i32 && Hi.getValueType() == MVT::i32 &&
"Unexpected VTs!");
MachineFunction &MF = CurDAG->getMachineFunction();
RISCVMachineFunctionInfo *FuncInfo = MF.getInfo<RISCVMachineFunctionInfo>();
SDLoc DL(N);
// We use the same frame index we use for moving two i32s into 64-bit FPR.
// This is an analogous operation.
int FI = FuncInfo->getMoveF64FrameIndex(MF);
MachinePointerInfo MPI = MachinePointerInfo::getFixedStack(MF, FI);
const TargetLowering &TLI = CurDAG->getTargetLoweringInfo();
SDValue StackSlot =
CurDAG->getFrameIndex(FI, TLI.getPointerTy(CurDAG->getDataLayout()));
SDValue Chain = CurDAG->getEntryNode();
Lo = CurDAG->getStore(Chain, DL, Lo, StackSlot, MPI, Align(8));
SDValue OffsetSlot =
CurDAG->getMemBasePlusOffset(StackSlot, TypeSize::Fixed(4), DL);
Hi = CurDAG->getStore(Chain, DL, Hi, OffsetSlot, MPI.getWithOffset(4),
Align(8));
Chain = CurDAG->getNode(ISD::TokenFactor, DL, MVT::Other, Lo, Hi);
SDVTList VTs = CurDAG->getVTList({VT, MVT::Other});
SDValue IntID =
CurDAG->getTargetConstant(Intrinsic::riscv_vlse, DL, MVT::i64);
SDValue Ops[] = {Chain, IntID, StackSlot,
CurDAG->getRegister(RISCV::X0, MVT::i64), VL};
SDValue Result = CurDAG->getMemIntrinsicNode(
ISD::INTRINSIC_W_CHAIN, DL, VTs, Ops, MVT::i64, MPI, Align(8),
MachineMemOperand::MOLoad);
// We're about to replace all uses of the SPLAT_VECTOR_SPLIT_I64 with the
// vlse we created. This will cause general havok on the dag because
// anything below the conversion could be folded into other existing nodes.
// To avoid invalidating 'I', back it up to the convert node.
--I;
CurDAG->ReplaceAllUsesOfValueWith(SDValue(N, 0), Result);
// Now that we did that, the node is dead. Increment the iterator to the
// next node to process, then delete N.
++I;
CurDAG->DeleteNode(N);
}
}
void RISCVDAGToDAGISel::PostprocessISelDAG() {
SelectionDAG::allnodes_iterator Position = CurDAG->allnodes_end();
bool MadeChange = false;
while (Position != CurDAG->allnodes_begin()) {
SDNode *N = &*--Position;
// Skip dead nodes and any non-machine opcodes.
if (N->use_empty() || !N->isMachineOpcode())
continue;
MadeChange |= doPeepholeSExtW(N);
MadeChange |= doPeepholeLoadStoreADDI(N);
}
if (MadeChange)
CurDAG->RemoveDeadNodes();
}
static SDNode *selectImm(SelectionDAG *CurDAG, const SDLoc &DL, int64_t Imm,
const RISCVSubtarget &Subtarget) {
MVT XLenVT = Subtarget.getXLenVT();
RISCVMatInt::InstSeq Seq =
RISCVMatInt::generateInstSeq(Imm, Subtarget.getFeatureBits());
SDNode *Result = nullptr;
SDValue SrcReg = CurDAG->getRegister(RISCV::X0, XLenVT);
for (RISCVMatInt::Inst &Inst : Seq) {
SDValue SDImm = CurDAG->getTargetConstant(Inst.Imm, DL, XLenVT);
if (Inst.Opc == RISCV::LUI)
Result = CurDAG->getMachineNode(RISCV::LUI, DL, XLenVT, SDImm);
else if (Inst.Opc == RISCV::ADDUW)
Result = CurDAG->getMachineNode(RISCV::ADDUW, DL, XLenVT, SrcReg,
CurDAG->getRegister(RISCV::X0, XLenVT));
else if (Inst.Opc == RISCV::SH1ADD || Inst.Opc == RISCV::SH2ADD ||
Inst.Opc == RISCV::SH3ADD)
Result = CurDAG->getMachineNode(Inst.Opc, DL, XLenVT, SrcReg, SrcReg);
else
Result = CurDAG->getMachineNode(Inst.Opc, DL, XLenVT, SrcReg, SDImm);
// Only the first instruction has X0 as its source.
SrcReg = SDValue(Result, 0);
}
return Result;
}
static SDValue createTupleImpl(SelectionDAG &CurDAG, ArrayRef<SDValue> Regs,
unsigned RegClassID, unsigned SubReg0) {
assert(Regs.size() >= 2 && Regs.size() <= 8);
SDLoc DL(Regs[0]);
SmallVector<SDValue, 8> Ops;
Ops.push_back(CurDAG.getTargetConstant(RegClassID, DL, MVT::i32));
for (unsigned I = 0; I < Regs.size(); ++I) {
Ops.push_back(Regs[I]);
Ops.push_back(CurDAG.getTargetConstant(SubReg0 + I, DL, MVT::i32));
}
SDNode *N =
CurDAG.getMachineNode(TargetOpcode::REG_SEQUENCE, DL, MVT::Untyped, Ops);
return SDValue(N, 0);
}
static SDValue createM1Tuple(SelectionDAG &CurDAG, ArrayRef<SDValue> Regs,
unsigned NF) {
static const unsigned RegClassIDs[] = {
RISCV::VRN2M1RegClassID, RISCV::VRN3M1RegClassID, RISCV::VRN4M1RegClassID,
RISCV::VRN5M1RegClassID, RISCV::VRN6M1RegClassID, RISCV::VRN7M1RegClassID,
RISCV::VRN8M1RegClassID};
return createTupleImpl(CurDAG, Regs, RegClassIDs[NF - 2], RISCV::sub_vrm1_0);
}
static SDValue createM2Tuple(SelectionDAG &CurDAG, ArrayRef<SDValue> Regs,
unsigned NF) {
static const unsigned RegClassIDs[] = {RISCV::VRN2M2RegClassID,
RISCV::VRN3M2RegClassID,
RISCV::VRN4M2RegClassID};
return createTupleImpl(CurDAG, Regs, RegClassIDs[NF - 2], RISCV::sub_vrm2_0);
}
static SDValue createM4Tuple(SelectionDAG &CurDAG, ArrayRef<SDValue> Regs,
unsigned NF) {
return createTupleImpl(CurDAG, Regs, RISCV::VRN2M4RegClassID,
RISCV::sub_vrm4_0);
}
static SDValue createTuple(SelectionDAG &CurDAG, ArrayRef<SDValue> Regs,
unsigned NF, RISCVII::VLMUL LMUL) {
switch (LMUL) {
default:
llvm_unreachable("Invalid LMUL.");
case RISCVII::VLMUL::LMUL_F8:
case RISCVII::VLMUL::LMUL_F4:
case RISCVII::VLMUL::LMUL_F2:
case RISCVII::VLMUL::LMUL_1:
return createM1Tuple(CurDAG, Regs, NF);
case RISCVII::VLMUL::LMUL_2:
return createM2Tuple(CurDAG, Regs, NF);
case RISCVII::VLMUL::LMUL_4:
return createM4Tuple(CurDAG, Regs, NF);
}
}
void RISCVDAGToDAGISel::addVectorLoadStoreOperands(
SDNode *Node, unsigned Log2SEW, const SDLoc &DL, unsigned CurOp,
bool IsMasked, bool IsStridedOrIndexed, SmallVectorImpl<SDValue> &Operands,
bool IsLoad, MVT *IndexVT) {
SDValue Chain = Node->getOperand(0);
SDValue Glue;
SDValue Base;
SelectBaseAddr(Node->getOperand(CurOp++), Base);
Operands.push_back(Base); // Base pointer.
if (IsStridedOrIndexed) {
Operands.push_back(Node->getOperand(CurOp++)); // Index.
if (IndexVT)
*IndexVT = Operands.back()->getSimpleValueType(0);
}
if (IsMasked) {
// Mask needs to be copied to V0.
SDValue Mask = Node->getOperand(CurOp++);
Chain = CurDAG->getCopyToReg(Chain, DL, RISCV::V0, Mask, SDValue());
Glue = Chain.getValue(1);
Operands.push_back(CurDAG->getRegister(RISCV::V0, Mask.getValueType()));
}
SDValue VL;
selectVLOp(Node->getOperand(CurOp++), VL);
Operands.push_back(VL);
MVT XLenVT = Subtarget->getXLenVT();
SDValue SEWOp = CurDAG->getTargetConstant(Log2SEW, DL, XLenVT);
Operands.push_back(SEWOp);
// Masked load has the tail policy argument.
if (IsMasked && IsLoad) {
// Policy must be a constant.
uint64_t Policy = Node->getConstantOperandVal(CurOp++);
SDValue PolicyOp = CurDAG->getTargetConstant(Policy, DL, XLenVT);
Operands.push_back(PolicyOp);
}
Operands.push_back(Chain); // Chain.
if (Glue)
Operands.push_back(Glue);
}
void RISCVDAGToDAGISel::selectVLSEG(SDNode *Node, bool IsMasked,
bool IsStrided) {
SDLoc DL(Node);
unsigned NF = Node->getNumValues() - 1;
MVT VT = Node->getSimpleValueType(0);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
unsigned CurOp = 2;
SmallVector<SDValue, 8> Operands;
if (IsMasked) {
SmallVector<SDValue, 8> Regs(Node->op_begin() + CurOp,
Node->op_begin() + CurOp + NF);
SDValue MaskedOff = createTuple(*CurDAG, Regs, NF, LMUL);
Operands.push_back(MaskedOff);
CurOp += NF;
}
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked, IsStrided,
Operands, /*IsLoad=*/true);
const RISCV::VLSEGPseudo *P =
RISCV::getVLSEGPseudo(NF, IsMasked, IsStrided, /*FF*/ false, Log2SEW,
static_cast<unsigned>(LMUL));
MachineSDNode *Load =
CurDAG->getMachineNode(P->Pseudo, DL, MVT::Untyped, MVT::Other, Operands);
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Load, {MemOp->getMemOperand()});
SDValue SuperReg = SDValue(Load, 0);
for (unsigned I = 0; I < NF; ++I) {
unsigned SubRegIdx = RISCVTargetLowering::getSubregIndexByMVT(VT, I);
ReplaceUses(SDValue(Node, I),
CurDAG->getTargetExtractSubreg(SubRegIdx, DL, VT, SuperReg));
}
ReplaceUses(SDValue(Node, NF), SDValue(Load, 1));
CurDAG->RemoveDeadNode(Node);
}
void RISCVDAGToDAGISel::selectVLSEGFF(SDNode *Node, bool IsMasked) {
SDLoc DL(Node);
unsigned NF = Node->getNumValues() - 2; // Do not count VL and Chain.
MVT VT = Node->getSimpleValueType(0);
MVT XLenVT = Subtarget->getXLenVT();
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
unsigned CurOp = 2;
SmallVector<SDValue, 7> Operands;
if (IsMasked) {
SmallVector<SDValue, 8> Regs(Node->op_begin() + CurOp,
Node->op_begin() + CurOp + NF);
SDValue MaskedOff = createTuple(*CurDAG, Regs, NF, LMUL);
Operands.push_back(MaskedOff);
CurOp += NF;
}
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked,
/*IsStridedOrIndexed*/ false, Operands,
/*IsLoad=*/true);
const RISCV::VLSEGPseudo *P =
RISCV::getVLSEGPseudo(NF, IsMasked, /*Strided*/ false, /*FF*/ true,
Log2SEW, static_cast<unsigned>(LMUL));
MachineSDNode *Load = CurDAG->getMachineNode(P->Pseudo, DL, MVT::Untyped,
MVT::Other, MVT::Glue, Operands);
SDNode *ReadVL = CurDAG->getMachineNode(RISCV::PseudoReadVL, DL, XLenVT,
/*Glue*/ SDValue(Load, 2));
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Load, {MemOp->getMemOperand()});
SDValue SuperReg = SDValue(Load, 0);
for (unsigned I = 0; I < NF; ++I) {
unsigned SubRegIdx = RISCVTargetLowering::getSubregIndexByMVT(VT, I);
ReplaceUses(SDValue(Node, I),
CurDAG->getTargetExtractSubreg(SubRegIdx, DL, VT, SuperReg));
}
ReplaceUses(SDValue(Node, NF), SDValue(ReadVL, 0)); // VL
ReplaceUses(SDValue(Node, NF + 1), SDValue(Load, 1)); // Chain
CurDAG->RemoveDeadNode(Node);
}
void RISCVDAGToDAGISel::selectVLXSEG(SDNode *Node, bool IsMasked,
bool IsOrdered) {
SDLoc DL(Node);
unsigned NF = Node->getNumValues() - 1;
MVT VT = Node->getSimpleValueType(0);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
unsigned CurOp = 2;
SmallVector<SDValue, 8> Operands;
if (IsMasked) {
SmallVector<SDValue, 8> Regs(Node->op_begin() + CurOp,
Node->op_begin() + CurOp + NF);
SDValue MaskedOff = createTuple(*CurDAG, Regs, NF, LMUL);
Operands.push_back(MaskedOff);
CurOp += NF;
}
MVT IndexVT;
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked,
/*IsStridedOrIndexed*/ true, Operands,
/*IsLoad=*/true, &IndexVT);
assert(VT.getVectorElementCount() == IndexVT.getVectorElementCount() &&
"Element count mismatch");
RISCVII::VLMUL IndexLMUL = RISCVTargetLowering::getLMUL(IndexVT);
unsigned IndexLog2EEW = Log2_32(IndexVT.getScalarSizeInBits());
const RISCV::VLXSEGPseudo *P = RISCV::getVLXSEGPseudo(
NF, IsMasked, IsOrdered, IndexLog2EEW, static_cast<unsigned>(LMUL),
static_cast<unsigned>(IndexLMUL));
MachineSDNode *Load =
CurDAG->getMachineNode(P->Pseudo, DL, MVT::Untyped, MVT::Other, Operands);
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Load, {MemOp->getMemOperand()});
SDValue SuperReg = SDValue(Load, 0);
for (unsigned I = 0; I < NF; ++I) {
unsigned SubRegIdx = RISCVTargetLowering::getSubregIndexByMVT(VT, I);
ReplaceUses(SDValue(Node, I),
CurDAG->getTargetExtractSubreg(SubRegIdx, DL, VT, SuperReg));
}
ReplaceUses(SDValue(Node, NF), SDValue(Load, 1));
CurDAG->RemoveDeadNode(Node);
}
void RISCVDAGToDAGISel::selectVSSEG(SDNode *Node, bool IsMasked,
bool IsStrided) {
SDLoc DL(Node);
unsigned NF = Node->getNumOperands() - 4;
if (IsStrided)
NF--;
if (IsMasked)
NF--;
MVT VT = Node->getOperand(2)->getSimpleValueType(0);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
SmallVector<SDValue, 8> Regs(Node->op_begin() + 2, Node->op_begin() + 2 + NF);
SDValue StoreVal = createTuple(*CurDAG, Regs, NF, LMUL);
SmallVector<SDValue, 8> Operands;
Operands.push_back(StoreVal);
unsigned CurOp = 2 + NF;
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked, IsStrided,
Operands);
const RISCV::VSSEGPseudo *P = RISCV::getVSSEGPseudo(
NF, IsMasked, IsStrided, Log2SEW, static_cast<unsigned>(LMUL));
MachineSDNode *Store =
CurDAG->getMachineNode(P->Pseudo, DL, Node->getValueType(0), Operands);
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Store, {MemOp->getMemOperand()});
ReplaceNode(Node, Store);
}
void RISCVDAGToDAGISel::selectVSXSEG(SDNode *Node, bool IsMasked,
bool IsOrdered) {
SDLoc DL(Node);
unsigned NF = Node->getNumOperands() - 5;
if (IsMasked)
--NF;
MVT VT = Node->getOperand(2)->getSimpleValueType(0);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
SmallVector<SDValue, 8> Regs(Node->op_begin() + 2, Node->op_begin() + 2 + NF);
SDValue StoreVal = createTuple(*CurDAG, Regs, NF, LMUL);
SmallVector<SDValue, 8> Operands;
Operands.push_back(StoreVal);
unsigned CurOp = 2 + NF;
MVT IndexVT;
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked,
/*IsStridedOrIndexed*/ true, Operands,
/*IsLoad=*/false, &IndexVT);
assert(VT.getVectorElementCount() == IndexVT.getVectorElementCount() &&
"Element count mismatch");
RISCVII::VLMUL IndexLMUL = RISCVTargetLowering::getLMUL(IndexVT);
unsigned IndexLog2EEW = Log2_32(IndexVT.getScalarSizeInBits());
const RISCV::VSXSEGPseudo *P = RISCV::getVSXSEGPseudo(
NF, IsMasked, IsOrdered, IndexLog2EEW, static_cast<unsigned>(LMUL),
static_cast<unsigned>(IndexLMUL));
MachineSDNode *Store =
CurDAG->getMachineNode(P->Pseudo, DL, Node->getValueType(0), Operands);
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Store, {MemOp->getMemOperand()});
ReplaceNode(Node, Store);
}
void RISCVDAGToDAGISel::Select(SDNode *Node) {
// If we have a custom node, we have already selected.
if (Node->isMachineOpcode()) {
LLVM_DEBUG(dbgs() << "== "; Node->dump(CurDAG); dbgs() << "\n");
Node->setNodeId(-1);
return;
}
// Instruction Selection not handled by the auto-generated tablegen selection
// should be handled here.
unsigned Opcode = Node->getOpcode();
MVT XLenVT = Subtarget->getXLenVT();
SDLoc DL(Node);
MVT VT = Node->getSimpleValueType(0);
switch (Opcode) {
case ISD::Constant: {
auto *ConstNode = cast<ConstantSDNode>(Node);
if (VT == XLenVT && ConstNode->isZero()) {
SDValue New =
CurDAG->getCopyFromReg(CurDAG->getEntryNode(), DL, RISCV::X0, XLenVT);
ReplaceNode(Node, New.getNode());
return;
}
int64_t Imm = ConstNode->getSExtValue();
// If the upper XLen-16 bits are not used, try to convert this to a simm12
// by sign extending bit 15.
if (isUInt<16>(Imm) && isInt<12>(SignExtend64(Imm, 16)) &&
hasAllHUsers(Node))
Imm = SignExtend64(Imm, 16);
// If the upper 32-bits are not used try to convert this into a simm32 by
// sign extending bit 32.
if (!isInt<32>(Imm) && isUInt<32>(Imm) && hasAllWUsers(Node))
Imm = SignExtend64(Imm, 32);
ReplaceNode(Node, selectImm(CurDAG, DL, Imm, *Subtarget));
return;
}
case ISD::FrameIndex: {
SDValue Imm = CurDAG->getTargetConstant(0, DL, XLenVT);
int FI = cast<FrameIndexSDNode>(Node)->getIndex();
SDValue TFI = CurDAG->getTargetFrameIndex(FI, VT);
ReplaceNode(Node, CurDAG->getMachineNode(RISCV::ADDI, DL, VT, TFI, Imm));
return;
}
case ISD::SRL: {
// We don't need this transform if zext.h is supported.
if (Subtarget->hasStdExtZbb() || Subtarget->hasStdExtZbp())
break;
// Optimize (srl (and X, 0xffff), C) ->
// (srli (slli X, (XLen-16), (XLen-16) + C)
// Taking into account that the 0xffff may have had lower bits unset by
// SimplifyDemandedBits. This avoids materializing the 0xffff immediate.
// This pattern occurs when type legalizing i16 right shifts.
// FIXME: This could be extended to other AND masks.
auto *N1C = dyn_cast<ConstantSDNode>(Node->getOperand(1));
if (N1C) {
uint64_t ShAmt = N1C->getZExtValue();
SDValue N0 = Node->getOperand(0);
if (ShAmt < 16 && N0.getOpcode() == ISD::AND && N0.hasOneUse() &&
isa<ConstantSDNode>(N0.getOperand(1))) {
uint64_t Mask = N0.getConstantOperandVal(1);
Mask |= maskTrailingOnes<uint64_t>(ShAmt);
if (Mask == 0xffff) {
unsigned LShAmt = Subtarget->getXLen() - 16;
SDNode *SLLI =
CurDAG->getMachineNode(RISCV::SLLI, DL, VT, N0->getOperand(0),
CurDAG->getTargetConstant(LShAmt, DL, VT));
SDNode *SRLI = CurDAG->getMachineNode(
RISCV::SRLI, DL, VT, SDValue(SLLI, 0),
CurDAG->getTargetConstant(LShAmt + ShAmt, DL, VT));
ReplaceNode(Node, SRLI);
return;
}
}
}
break;
}
case ISD::AND: {
auto *N1C = dyn_cast<ConstantSDNode>(Node->getOperand(1));
if (!N1C)
break;
SDValue N0 = Node->getOperand(0);
bool LeftShift = N0.getOpcode() == ISD::SHL;
if (!LeftShift && N0.getOpcode() != ISD::SRL)
break;
auto *C = dyn_cast<ConstantSDNode>(N0.getOperand(1));
if (!C)
break;
uint64_t C2 = C->getZExtValue();
unsigned XLen = Subtarget->getXLen();
if (!C2 || C2 >= XLen)
break;
uint64_t C1 = N1C->getZExtValue();
// Keep track of whether this is a andi, zext.h, or zext.w.
bool ZExtOrANDI = isInt<12>(N1C->getSExtValue());
if (C1 == UINT64_C(0xFFFF) &&
(Subtarget->hasStdExtZbb() || Subtarget->hasStdExtZbp()))
ZExtOrANDI = true;
if (C1 == UINT64_C(0xFFFFFFFF) && Subtarget->hasStdExtZba())
ZExtOrANDI = true;
// Clear irrelevant bits in the mask.
if (LeftShift)
C1 &= maskTrailingZeros<uint64_t>(C2);
else
C1 &= maskTrailingOnes<uint64_t>(XLen - C2);
// Some transforms should only be done if the shift has a single use or
// the AND would become (srli (slli X, 32), 32)
bool OneUseOrZExtW = N0.hasOneUse() || C1 == UINT64_C(0xFFFFFFFF);
SDValue X = N0.getOperand(0);
// Turn (and (srl x, c2) c1) -> (srli (slli x, c3-c2), c3) if c1 is a mask
// with c3 leading zeros.
if (!LeftShift && isMask_64(C1)) {
uint64_t C3 = XLen - (64 - countLeadingZeros(C1));
if (C2 < C3) {
// If the number of leading zeros is C2+32 this can be SRLIW.
if (C2 + 32 == C3) {
SDNode *SRLIW =
CurDAG->getMachineNode(RISCV::SRLIW, DL, XLenVT, X,
CurDAG->getTargetConstant(C2, DL, XLenVT));
ReplaceNode(Node, SRLIW);
return;
}
// (and (srl (sexti32 Y), c2), c1) -> (srliw (sraiw Y, 31), c3 - 32) if
// c1 is a mask with c3 leading zeros and c2 >= 32 and c3-c2==1.
//
// This pattern occurs when (i32 (srl (sra 31), c3 - 32)) is type
// legalized and goes through DAG combine.
SDValue Y;
if (C2 >= 32 && (C3 - C2) == 1 && N0.hasOneUse() &&
selectSExti32(X, Y)) {
SDNode *SRAIW =
CurDAG->getMachineNode(RISCV::SRAIW, DL, XLenVT, Y,
CurDAG->getTargetConstant(31, DL, XLenVT));
SDNode *SRLIW = CurDAG->getMachineNode(
RISCV::SRLIW, DL, XLenVT, SDValue(SRAIW, 0),
CurDAG->getTargetConstant(C3 - 32, DL, XLenVT));
ReplaceNode(Node, SRLIW);
return;
}
// (srli (slli x, c3-c2), c3).
if (OneUseOrZExtW && !ZExtOrANDI) {
SDNode *SLLI = CurDAG->getMachineNode(
RISCV::SLLI, DL, XLenVT, X,
CurDAG->getTargetConstant(C3 - C2, DL, XLenVT));
SDNode *SRLI =
CurDAG->getMachineNode(RISCV::SRLI, DL, XLenVT, SDValue(SLLI, 0),
CurDAG->getTargetConstant(C3, DL, XLenVT));
ReplaceNode(Node, SRLI);
return;
}
}
}
// Turn (and (shl x, c2), c1) -> (srli (slli c2+c3), c3) if c1 is a mask
// shifted by c2 bits with c3 leading zeros.
if (LeftShift && isShiftedMask_64(C1)) {
uint64_t C3 = XLen - (64 - countLeadingZeros(C1));
if (C2 + C3 < XLen &&
C1 == (maskTrailingOnes<uint64_t>(XLen - (C2 + C3)) << C2)) {
// Use slli.uw when possible.
if ((XLen - (C2 + C3)) == 32 && Subtarget->hasStdExtZba()) {
SDNode *SLLIUW =
CurDAG->getMachineNode(RISCV::SLLIUW, DL, XLenVT, X,
CurDAG->getTargetConstant(C2, DL, XLenVT));
ReplaceNode(Node, SLLIUW);
return;
}
// (srli (slli c2+c3), c3)
if (OneUseOrZExtW && !ZExtOrANDI) {
SDNode *SLLI = CurDAG->getMachineNode(
RISCV::SLLI, DL, XLenVT, X,
CurDAG->getTargetConstant(C2 + C3, DL, XLenVT));
SDNode *SRLI =
CurDAG->getMachineNode(RISCV::SRLI, DL, XLenVT, SDValue(SLLI, 0),
CurDAG->getTargetConstant(C3, DL, XLenVT));
ReplaceNode(Node, SRLI);
return;
}
}
}
// Turn (and (shr x, c2), c1) -> (slli (srli x, c2+c3), c3) if c1 is a
// shifted mask with c2 leading zeros and c3 trailing zeros.
if (!LeftShift && isShiftedMask_64(C1)) {
uint64_t Leading = XLen - (64 - countLeadingZeros(C1));
uint64_t C3 = countTrailingZeros(C1);
if (Leading == C2 && C2 + C3 < XLen && OneUseOrZExtW && !ZExtOrANDI) {
SDNode *SRLI = CurDAG->getMachineNode(
RISCV::SRLI, DL, XLenVT, X,
CurDAG->getTargetConstant(C2 + C3, DL, XLenVT));
SDNode *SLLI =
CurDAG->getMachineNode(RISCV::SLLI, DL, XLenVT, SDValue(SRLI, 0),
CurDAG->getTargetConstant(C3, DL, XLenVT));
ReplaceNode(Node, SLLI);
return;
}
// If the leading zero count is C2+32, we can use SRLIW instead of SRLI.
if (Leading > 32 && (Leading - 32) == C2 && C2 + C3 < 32 &&
OneUseOrZExtW && !ZExtOrANDI) {
SDNode *SRLIW = CurDAG->getMachineNode(
RISCV::SRLIW, DL, XLenVT, X,
CurDAG->getTargetConstant(C2 + C3, DL, XLenVT));
SDNode *SLLI =
CurDAG->getMachineNode(RISCV::SLLI, DL, XLenVT, SDValue(SRLIW, 0),
CurDAG->getTargetConstant(C3, DL, XLenVT));
ReplaceNode(Node, SLLI);
return;
}
}
// Turn (and (shl x, c2), c1) -> (slli (srli x, c3-c2), c3) if c1 is a
// shifted mask with no leading zeros and c3 trailing zeros.
if (LeftShift && isShiftedMask_64(C1)) {
uint64_t Leading = XLen - (64 - countLeadingZeros(C1));
uint64_t C3 = countTrailingZeros(C1);
if (Leading == 0 && C2 < C3 && OneUseOrZExtW && !ZExtOrANDI) {
SDNode *SRLI = CurDAG->getMachineNode(
RISCV::SRLI, DL, XLenVT, X,
CurDAG->getTargetConstant(C3 - C2, DL, XLenVT));
SDNode *SLLI =
CurDAG->getMachineNode(RISCV::SLLI, DL, XLenVT, SDValue(SRLI, 0),
CurDAG->getTargetConstant(C3, DL, XLenVT));
ReplaceNode(Node, SLLI);
return;
}
// If we have (32-C2) leading zeros, we can use SRLIW instead of SRLI.
if (C2 < C3 && Leading + C2 == 32 && OneUseOrZExtW && !ZExtOrANDI) {
SDNode *SRLIW = CurDAG->getMachineNode(
RISCV::SRLIW, DL, XLenVT, X,
CurDAG->getTargetConstant(C3 - C2, DL, XLenVT));
SDNode *SLLI =
CurDAG->getMachineNode(RISCV::SLLI, DL, XLenVT, SDValue(SRLIW, 0),
CurDAG->getTargetConstant(C3, DL, XLenVT));
ReplaceNode(Node, SLLI);
return;
}
}
break;
}
case ISD::INTRINSIC_WO_CHAIN: {
unsigned IntNo = Node->getConstantOperandVal(0);
switch (IntNo) {
// By default we do not custom select any intrinsic.
default:
break;
case Intrinsic::riscv_vmsgeu:
case Intrinsic::riscv_vmsge: {
SDValue Src1 = Node->getOperand(1);
SDValue Src2 = Node->getOperand(2);
// Only custom select scalar second operand.
if (Src2.getValueType() != XLenVT)
break;
// Small constants are handled with patterns.
if (auto *C = dyn_cast<ConstantSDNode>(Src2)) {
int64_t CVal = C->getSExtValue();
if (CVal >= -15 && CVal <= 16)
break;
}
bool IsUnsigned = IntNo == Intrinsic::riscv_vmsgeu;
MVT Src1VT = Src1.getSimpleValueType();
unsigned VMSLTOpcode, VMNANDOpcode;
switch (RISCVTargetLowering::getLMUL(Src1VT)) {
default:
llvm_unreachable("Unexpected LMUL!");
case RISCVII::VLMUL::LMUL_F8:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_MF8 : RISCV::PseudoVMSLT_VX_MF8;
VMNANDOpcode = RISCV::PseudoVMNAND_MM_MF8;
break;
case RISCVII::VLMUL::LMUL_F4:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_MF4 : RISCV::PseudoVMSLT_VX_MF4;
VMNANDOpcode = RISCV::PseudoVMNAND_MM_MF4;
break;
case RISCVII::VLMUL::LMUL_F2:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_MF2 : RISCV::PseudoVMSLT_VX_MF2;
VMNANDOpcode = RISCV::PseudoVMNAND_MM_MF2;
break;
case RISCVII::VLMUL::LMUL_1:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_M1 : RISCV::PseudoVMSLT_VX_M1;
VMNANDOpcode = RISCV::PseudoVMNAND_MM_M1;
break;
case RISCVII::VLMUL::LMUL_2:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_M2 : RISCV::PseudoVMSLT_VX_M2;
VMNANDOpcode = RISCV::PseudoVMNAND_MM_M2;
break;
case RISCVII::VLMUL::LMUL_4:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_M4 : RISCV::PseudoVMSLT_VX_M4;
VMNANDOpcode = RISCV::PseudoVMNAND_MM_M4;
break;
case RISCVII::VLMUL::LMUL_8:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_M8 : RISCV::PseudoVMSLT_VX_M8;
VMNANDOpcode = RISCV::PseudoVMNAND_MM_M8;
break;
}
SDValue SEW = CurDAG->getTargetConstant(
Log2_32(Src1VT.getScalarSizeInBits()), DL, XLenVT);
SDValue VL;
selectVLOp(Node->getOperand(3), VL);
// Expand to
// vmslt{u}.vx vd, va, x; vmnand.mm vd, vd, vd
SDValue Cmp = SDValue(
CurDAG->getMachineNode(VMSLTOpcode, DL, VT, {Src1, Src2, VL, SEW}),
0);
ReplaceNode(Node, CurDAG->getMachineNode(VMNANDOpcode, DL, VT,
{Cmp, Cmp, VL, SEW}));
return;
}
case Intrinsic::riscv_vmsgeu_mask:
case Intrinsic::riscv_vmsge_mask: {
SDValue Src1 = Node->getOperand(2);
SDValue Src2 = Node->getOperand(3);
// Only custom select scalar second operand.
if (Src2.getValueType() != XLenVT)
break;
// Small constants are handled with patterns.
if (auto *C = dyn_cast<ConstantSDNode>(Src2)) {
int64_t CVal = C->getSExtValue();
if (CVal >= -15 && CVal <= 16)
break;
}
bool IsUnsigned = IntNo == Intrinsic::riscv_vmsgeu_mask;
MVT Src1VT = Src1.getSimpleValueType();
unsigned VMSLTOpcode, VMSLTMaskOpcode, VMXOROpcode, VMANDNOpcode;
switch (RISCVTargetLowering::getLMUL(Src1VT)) {
default:
llvm_unreachable("Unexpected LMUL!");
case RISCVII::VLMUL::LMUL_F8:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_MF8 : RISCV::PseudoVMSLT_VX_MF8;
VMSLTMaskOpcode = IsUnsigned ? RISCV::PseudoVMSLTU_VX_MF8_MASK
: RISCV::PseudoVMSLT_VX_MF8_MASK;
break;
case RISCVII::VLMUL::LMUL_F4:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_MF4 : RISCV::PseudoVMSLT_VX_MF4;
VMSLTMaskOpcode = IsUnsigned ? RISCV::PseudoVMSLTU_VX_MF4_MASK
: RISCV::PseudoVMSLT_VX_MF4_MASK;
break;
case RISCVII::VLMUL::LMUL_F2:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_MF2 : RISCV::PseudoVMSLT_VX_MF2;
VMSLTMaskOpcode = IsUnsigned ? RISCV::PseudoVMSLTU_VX_MF2_MASK
: RISCV::PseudoVMSLT_VX_MF2_MASK;
break;
case RISCVII::VLMUL::LMUL_1:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_M1 : RISCV::PseudoVMSLT_VX_M1;
VMSLTMaskOpcode = IsUnsigned ? RISCV::PseudoVMSLTU_VX_M1_MASK
: RISCV::PseudoVMSLT_VX_M1_MASK;
break;
case RISCVII::VLMUL::LMUL_2:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_M2 : RISCV::PseudoVMSLT_VX_M2;
VMSLTMaskOpcode = IsUnsigned ? RISCV::PseudoVMSLTU_VX_M2_MASK
: RISCV::PseudoVMSLT_VX_M2_MASK;
break;
case RISCVII::VLMUL::LMUL_4:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_M4 : RISCV::PseudoVMSLT_VX_M4;
VMSLTMaskOpcode = IsUnsigned ? RISCV::PseudoVMSLTU_VX_M4_MASK
: RISCV::PseudoVMSLT_VX_M4_MASK;
break;
case RISCVII::VLMUL::LMUL_8:
VMSLTOpcode =
IsUnsigned ? RISCV::PseudoVMSLTU_VX_M8 : RISCV::PseudoVMSLT_VX_M8;
VMSLTMaskOpcode = IsUnsigned ? RISCV::PseudoVMSLTU_VX_M8_MASK
: RISCV::PseudoVMSLT_VX_M8_MASK;
break;
}
// Mask operations use the LMUL from the mask type.
switch (RISCVTargetLowering::getLMUL(VT)) {
default:
llvm_unreachable("Unexpected LMUL!");
case RISCVII::VLMUL::LMUL_F8:
VMXOROpcode = RISCV::PseudoVMXOR_MM_MF8;
VMANDNOpcode = RISCV::PseudoVMANDN_MM_MF8;
break;
case RISCVII::VLMUL::LMUL_F4:
VMXOROpcode = RISCV::PseudoVMXOR_MM_MF4;
VMANDNOpcode = RISCV::PseudoVMANDN_MM_MF4;
break;
case RISCVII::VLMUL::LMUL_F2:
VMXOROpcode = RISCV::PseudoVMXOR_MM_MF2;
VMANDNOpcode = RISCV::PseudoVMANDN_MM_MF2;
break;
case RISCVII::VLMUL::LMUL_1:
VMXOROpcode = RISCV::PseudoVMXOR_MM_M1;
VMANDNOpcode = RISCV::PseudoVMANDN_MM_M1;
break;
case RISCVII::VLMUL::LMUL_2:
VMXOROpcode = RISCV::PseudoVMXOR_MM_M2;
VMANDNOpcode = RISCV::PseudoVMANDN_MM_M2;
break;
case RISCVII::VLMUL::LMUL_4:
VMXOROpcode = RISCV::PseudoVMXOR_MM_M4;
VMANDNOpcode = RISCV::PseudoVMANDN_MM_M4;
break;
case RISCVII::VLMUL::LMUL_8:
VMXOROpcode = RISCV::PseudoVMXOR_MM_M8;
VMANDNOpcode = RISCV::PseudoVMANDN_MM_M8;
break;
}
SDValue SEW = CurDAG->getTargetConstant(
Log2_32(Src1VT.getScalarSizeInBits()), DL, XLenVT);
SDValue MaskSEW = CurDAG->getTargetConstant(0, DL, XLenVT);
SDValue VL;
selectVLOp(Node->getOperand(5), VL);
SDValue MaskedOff = Node->getOperand(1);
SDValue Mask = Node->getOperand(4);
// If the MaskedOff value and the Mask are the same value use
// vmslt{u}.vx vt, va, x; vmandn.mm vd, vd, vt
// This avoids needing to copy v0 to vd before starting the next sequence.
if (Mask == MaskedOff) {
SDValue Cmp = SDValue(
CurDAG->getMachineNode(VMSLTOpcode, DL, VT, {Src1, Src2, VL, SEW}),
0);
ReplaceNode(Node, CurDAG->getMachineNode(VMANDNOpcode, DL, VT,
{Mask, Cmp, VL, MaskSEW}));
return;
}
// Mask needs to be copied to V0.
SDValue Chain = CurDAG->getCopyToReg(CurDAG->getEntryNode(), DL,
RISCV::V0, Mask, SDValue());
SDValue Glue = Chain.getValue(1);
SDValue V0 = CurDAG->getRegister(RISCV::V0, VT);
// Otherwise use
// vmslt{u}.vx vd, va, x, v0.t; vmxor.mm vd, vd, v0
SDValue Cmp = SDValue(
CurDAG->getMachineNode(VMSLTMaskOpcode, DL, VT,
{MaskedOff, Src1, Src2, V0, VL, SEW, Glue}),
0);
ReplaceNode(Node, CurDAG->getMachineNode(VMXOROpcode, DL, VT,
{Cmp, Mask, VL, MaskSEW}));
return;
}
}
break;
}
case ISD::INTRINSIC_W_CHAIN: {
unsigned IntNo = cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue();
switch (IntNo) {
// By default we do not custom select any intrinsic.
default:
break;
case Intrinsic::riscv_vsetvli:
case Intrinsic::riscv_vsetvlimax: {
if (!Subtarget->hasVInstructions())
break;
bool VLMax = IntNo == Intrinsic::riscv_vsetvlimax;
unsigned Offset = VLMax ? 2 : 3;
assert(Node->getNumOperands() == Offset + 2 &&
"Unexpected number of operands");
unsigned SEW =
RISCVVType::decodeVSEW(Node->getConstantOperandVal(Offset) & 0x7);
RISCVII::VLMUL VLMul = static_cast<RISCVII::VLMUL>(
Node->getConstantOperandVal(Offset + 1) & 0x7);
unsigned VTypeI = RISCVVType::encodeVTYPE(
VLMul, SEW, /*TailAgnostic*/ true, /*MaskAgnostic*/ false);
SDValue VTypeIOp = CurDAG->getTargetConstant(VTypeI, DL, XLenVT);
SDValue VLOperand;
unsigned Opcode = RISCV::PseudoVSETVLI;
if (VLMax) {
VLOperand = CurDAG->getRegister(RISCV::X0, XLenVT);
Opcode = RISCV::PseudoVSETVLIX0;
} else {
VLOperand = Node->getOperand(2);
if (auto *C = dyn_cast<ConstantSDNode>(VLOperand)) {
uint64_t AVL = C->getZExtValue();
if (isUInt<5>(AVL)) {
SDValue VLImm = CurDAG->getTargetConstant(AVL, DL, XLenVT);
ReplaceNode(
Node, CurDAG->getMachineNode(RISCV::PseudoVSETIVLI, DL, XLenVT,
MVT::Other, VLImm, VTypeIOp,
/* Chain */ Node->getOperand(0)));
return;
}
}
}
ReplaceNode(Node,
CurDAG->getMachineNode(Opcode, DL, XLenVT,
MVT::Other, VLOperand, VTypeIOp,
/* Chain */ Node->getOperand(0)));
return;
}
case Intrinsic::riscv_vlseg2:
case Intrinsic::riscv_vlseg3:
case Intrinsic::riscv_vlseg4:
case Intrinsic::riscv_vlseg5:
case Intrinsic::riscv_vlseg6:
case Intrinsic::riscv_vlseg7:
case Intrinsic::riscv_vlseg8: {
selectVLSEG(Node, /*IsMasked*/ false, /*IsStrided*/ false);
return;
}
case Intrinsic::riscv_vlseg2_mask:
case Intrinsic::riscv_vlseg3_mask:
case Intrinsic::riscv_vlseg4_mask:
case Intrinsic::riscv_vlseg5_mask:
case Intrinsic::riscv_vlseg6_mask:
case Intrinsic::riscv_vlseg7_mask:
case Intrinsic::riscv_vlseg8_mask: {
selectVLSEG(Node, /*IsMasked*/ true, /*IsStrided*/ false);
return;
}
case Intrinsic::riscv_vlsseg2:
case Intrinsic::riscv_vlsseg3:
case Intrinsic::riscv_vlsseg4:
case Intrinsic::riscv_vlsseg5:
case Intrinsic::riscv_vlsseg6:
case Intrinsic::riscv_vlsseg7:
case Intrinsic::riscv_vlsseg8: {
selectVLSEG(Node, /*IsMasked*/ false, /*IsStrided*/ true);
return;
}
case Intrinsic::riscv_vlsseg2_mask:
case Intrinsic::riscv_vlsseg3_mask:
case Intrinsic::riscv_vlsseg4_mask:
case Intrinsic::riscv_vlsseg5_mask:
case Intrinsic::riscv_vlsseg6_mask:
case Intrinsic::riscv_vlsseg7_mask:
case Intrinsic::riscv_vlsseg8_mask: {
selectVLSEG(Node, /*IsMasked*/ true, /*IsStrided*/ true);
return;
}
case Intrinsic::riscv_vloxseg2:
case Intrinsic::riscv_vloxseg3:
case Intrinsic::riscv_vloxseg4:
case Intrinsic::riscv_vloxseg5:
case Intrinsic::riscv_vloxseg6:
case Intrinsic::riscv_vloxseg7:
case Intrinsic::riscv_vloxseg8:
selectVLXSEG(Node, /*IsMasked*/ false, /*IsOrdered*/ true);
return;
case Intrinsic::riscv_vluxseg2:
case Intrinsic::riscv_vluxseg3:
case Intrinsic::riscv_vluxseg4:
case Intrinsic::riscv_vluxseg5:
case Intrinsic::riscv_vluxseg6:
case Intrinsic::riscv_vluxseg7:
case Intrinsic::riscv_vluxseg8:
selectVLXSEG(Node, /*IsMasked*/ false, /*IsOrdered*/ false);
return;
case Intrinsic::riscv_vloxseg2_mask:
case Intrinsic::riscv_vloxseg3_mask:
case Intrinsic::riscv_vloxseg4_mask:
case Intrinsic::riscv_vloxseg5_mask:
case Intrinsic::riscv_vloxseg6_mask:
case Intrinsic::riscv_vloxseg7_mask:
case Intrinsic::riscv_vloxseg8_mask:
selectVLXSEG(Node, /*IsMasked*/ true, /*IsOrdered*/ true);
return;
case Intrinsic::riscv_vluxseg2_mask:
case Intrinsic::riscv_vluxseg3_mask:
case Intrinsic::riscv_vluxseg4_mask:
case Intrinsic::riscv_vluxseg5_mask:
case Intrinsic::riscv_vluxseg6_mask:
case Intrinsic::riscv_vluxseg7_mask:
case Intrinsic::riscv_vluxseg8_mask:
selectVLXSEG(Node, /*IsMasked*/ true, /*IsOrdered*/ false);
return;
case Intrinsic::riscv_vlseg8ff:
case Intrinsic::riscv_vlseg7ff:
case Intrinsic::riscv_vlseg6ff:
case Intrinsic::riscv_vlseg5ff:
case Intrinsic::riscv_vlseg4ff:
case Intrinsic::riscv_vlseg3ff:
case Intrinsic::riscv_vlseg2ff: {
selectVLSEGFF(Node, /*IsMasked*/ false);
return;
}
case Intrinsic::riscv_vlseg8ff_mask:
case Intrinsic::riscv_vlseg7ff_mask:
case Intrinsic::riscv_vlseg6ff_mask:
case Intrinsic::riscv_vlseg5ff_mask:
case Intrinsic::riscv_vlseg4ff_mask:
case Intrinsic::riscv_vlseg3ff_mask:
case Intrinsic::riscv_vlseg2ff_mask: {
selectVLSEGFF(Node, /*IsMasked*/ true);
return;
}
case Intrinsic::riscv_vloxei:
case Intrinsic::riscv_vloxei_mask:
case Intrinsic::riscv_vluxei:
case Intrinsic::riscv_vluxei_mask: {
bool IsMasked = IntNo == Intrinsic::riscv_vloxei_mask ||
IntNo == Intrinsic::riscv_vluxei_mask;
bool IsOrdered = IntNo == Intrinsic::riscv_vloxei ||
IntNo == Intrinsic::riscv_vloxei_mask;
MVT VT = Node->getSimpleValueType(0);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
unsigned CurOp = 2;
SmallVector<SDValue, 8> Operands;
if (IsMasked)
Operands.push_back(Node->getOperand(CurOp++));
MVT IndexVT;
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked,
/*IsStridedOrIndexed*/ true, Operands,
/*IsLoad=*/true, &IndexVT);
assert(VT.getVectorElementCount() == IndexVT.getVectorElementCount() &&
"Element count mismatch");
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
RISCVII::VLMUL IndexLMUL = RISCVTargetLowering::getLMUL(IndexVT);
unsigned IndexLog2EEW = Log2_32(IndexVT.getScalarSizeInBits());
const RISCV::VLX_VSXPseudo *P = RISCV::getVLXPseudo(
IsMasked, IsOrdered, IndexLog2EEW, static_cast<unsigned>(LMUL),
static_cast<unsigned>(IndexLMUL));
MachineSDNode *Load =
CurDAG->getMachineNode(P->Pseudo, DL, Node->getVTList(), Operands);
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Load, {MemOp->getMemOperand()});
ReplaceNode(Node, Load);
return;
}
case Intrinsic::riscv_vlm:
case Intrinsic::riscv_vle:
case Intrinsic::riscv_vle_mask:
case Intrinsic::riscv_vlse:
case Intrinsic::riscv_vlse_mask: {
bool IsMasked = IntNo == Intrinsic::riscv_vle_mask ||
IntNo == Intrinsic::riscv_vlse_mask;
bool IsStrided =
IntNo == Intrinsic::riscv_vlse || IntNo == Intrinsic::riscv_vlse_mask;
MVT VT = Node->getSimpleValueType(0);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
unsigned CurOp = 2;
SmallVector<SDValue, 8> Operands;
if (IsMasked)
Operands.push_back(Node->getOperand(CurOp++));
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked, IsStrided,
Operands, /*IsLoad=*/true);
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
const RISCV::VLEPseudo *P =
RISCV::getVLEPseudo(IsMasked, IsStrided, /*FF*/ false, Log2SEW,
static_cast<unsigned>(LMUL));
MachineSDNode *Load =
CurDAG->getMachineNode(P->Pseudo, DL, Node->getVTList(), Operands);
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Load, {MemOp->getMemOperand()});
ReplaceNode(Node, Load);
return;
}
case Intrinsic::riscv_vleff:
case Intrinsic::riscv_vleff_mask: {
bool IsMasked = IntNo == Intrinsic::riscv_vleff_mask;
MVT VT = Node->getSimpleValueType(0);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
unsigned CurOp = 2;
SmallVector<SDValue, 7> Operands;
if (IsMasked)
Operands.push_back(Node->getOperand(CurOp++));
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked,
/*IsStridedOrIndexed*/ false, Operands,
/*IsLoad=*/true);
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
const RISCV::VLEPseudo *P =
RISCV::getVLEPseudo(IsMasked, /*Strided*/ false, /*FF*/ true, Log2SEW,
static_cast<unsigned>(LMUL));
MachineSDNode *Load =
CurDAG->getMachineNode(P->Pseudo, DL, Node->getValueType(0),
MVT::Other, MVT::Glue, Operands);
SDNode *ReadVL = CurDAG->getMachineNode(RISCV::PseudoReadVL, DL, XLenVT,
/*Glue*/ SDValue(Load, 2));
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Load, {MemOp->getMemOperand()});
ReplaceUses(SDValue(Node, 0), SDValue(Load, 0));
ReplaceUses(SDValue(Node, 1), SDValue(ReadVL, 0)); // VL
ReplaceUses(SDValue(Node, 2), SDValue(Load, 1)); // Chain
CurDAG->RemoveDeadNode(Node);
return;
}
}
break;
}
case ISD::INTRINSIC_VOID: {
unsigned IntNo = cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue();
switch (IntNo) {
case Intrinsic::riscv_vsseg2:
case Intrinsic::riscv_vsseg3:
case Intrinsic::riscv_vsseg4:
case Intrinsic::riscv_vsseg5:
case Intrinsic::riscv_vsseg6:
case Intrinsic::riscv_vsseg7:
case Intrinsic::riscv_vsseg8: {
selectVSSEG(Node, /*IsMasked*/ false, /*IsStrided*/ false);
return;
}
case Intrinsic::riscv_vsseg2_mask:
case Intrinsic::riscv_vsseg3_mask:
case Intrinsic::riscv_vsseg4_mask:
case Intrinsic::riscv_vsseg5_mask:
case Intrinsic::riscv_vsseg6_mask:
case Intrinsic::riscv_vsseg7_mask:
case Intrinsic::riscv_vsseg8_mask: {
selectVSSEG(Node, /*IsMasked*/ true, /*IsStrided*/ false);
return;
}
case Intrinsic::riscv_vssseg2:
case Intrinsic::riscv_vssseg3:
case Intrinsic::riscv_vssseg4:
case Intrinsic::riscv_vssseg5:
case Intrinsic::riscv_vssseg6:
case Intrinsic::riscv_vssseg7:
case Intrinsic::riscv_vssseg8: {
selectVSSEG(Node, /*IsMasked*/ false, /*IsStrided*/ true);
return;
}
case Intrinsic::riscv_vssseg2_mask:
case Intrinsic::riscv_vssseg3_mask:
case Intrinsic::riscv_vssseg4_mask:
case Intrinsic::riscv_vssseg5_mask:
case Intrinsic::riscv_vssseg6_mask:
case Intrinsic::riscv_vssseg7_mask:
case Intrinsic::riscv_vssseg8_mask: {
selectVSSEG(Node, /*IsMasked*/ true, /*IsStrided*/ true);
return;
}
case Intrinsic::riscv_vsoxseg2:
case Intrinsic::riscv_vsoxseg3:
case Intrinsic::riscv_vsoxseg4:
case Intrinsic::riscv_vsoxseg5:
case Intrinsic::riscv_vsoxseg6:
case Intrinsic::riscv_vsoxseg7:
case Intrinsic::riscv_vsoxseg8:
selectVSXSEG(Node, /*IsMasked*/ false, /*IsOrdered*/ true);
return;
case Intrinsic::riscv_vsuxseg2:
case Intrinsic::riscv_vsuxseg3:
case Intrinsic::riscv_vsuxseg4:
case Intrinsic::riscv_vsuxseg5:
case Intrinsic::riscv_vsuxseg6:
case Intrinsic::riscv_vsuxseg7:
case Intrinsic::riscv_vsuxseg8:
selectVSXSEG(Node, /*IsMasked*/ false, /*IsOrdered*/ false);
return;
case Intrinsic::riscv_vsoxseg2_mask:
case Intrinsic::riscv_vsoxseg3_mask:
case Intrinsic::riscv_vsoxseg4_mask:
case Intrinsic::riscv_vsoxseg5_mask:
case Intrinsic::riscv_vsoxseg6_mask:
case Intrinsic::riscv_vsoxseg7_mask:
case Intrinsic::riscv_vsoxseg8_mask:
selectVSXSEG(Node, /*IsMasked*/ true, /*IsOrdered*/ true);
return;
case Intrinsic::riscv_vsuxseg2_mask:
case Intrinsic::riscv_vsuxseg3_mask:
case Intrinsic::riscv_vsuxseg4_mask:
case Intrinsic::riscv_vsuxseg5_mask:
case Intrinsic::riscv_vsuxseg6_mask:
case Intrinsic::riscv_vsuxseg7_mask:
case Intrinsic::riscv_vsuxseg8_mask:
selectVSXSEG(Node, /*IsMasked*/ true, /*IsOrdered*/ false);
return;
case Intrinsic::riscv_vsoxei:
case Intrinsic::riscv_vsoxei_mask:
case Intrinsic::riscv_vsuxei:
case Intrinsic::riscv_vsuxei_mask: {
bool IsMasked = IntNo == Intrinsic::riscv_vsoxei_mask ||
IntNo == Intrinsic::riscv_vsuxei_mask;
bool IsOrdered = IntNo == Intrinsic::riscv_vsoxei ||
IntNo == Intrinsic::riscv_vsoxei_mask;
MVT VT = Node->getOperand(2)->getSimpleValueType(0);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
unsigned CurOp = 2;
SmallVector<SDValue, 8> Operands;
Operands.push_back(Node->getOperand(CurOp++)); // Store value.
MVT IndexVT;
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked,
/*IsStridedOrIndexed*/ true, Operands,
/*IsLoad=*/false, &IndexVT);
assert(VT.getVectorElementCount() == IndexVT.getVectorElementCount() &&
"Element count mismatch");
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
RISCVII::VLMUL IndexLMUL = RISCVTargetLowering::getLMUL(IndexVT);
unsigned IndexLog2EEW = Log2_32(IndexVT.getScalarSizeInBits());
const RISCV::VLX_VSXPseudo *P = RISCV::getVSXPseudo(
IsMasked, IsOrdered, IndexLog2EEW, static_cast<unsigned>(LMUL),
static_cast<unsigned>(IndexLMUL));
MachineSDNode *Store =
CurDAG->getMachineNode(P->Pseudo, DL, Node->getVTList(), Operands);
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Store, {MemOp->getMemOperand()});
ReplaceNode(Node, Store);
return;
}
case Intrinsic::riscv_vsm:
case Intrinsic::riscv_vse:
case Intrinsic::riscv_vse_mask:
case Intrinsic::riscv_vsse:
case Intrinsic::riscv_vsse_mask: {
bool IsMasked = IntNo == Intrinsic::riscv_vse_mask ||
IntNo == Intrinsic::riscv_vsse_mask;
bool IsStrided =
IntNo == Intrinsic::riscv_vsse || IntNo == Intrinsic::riscv_vsse_mask;
MVT VT = Node->getOperand(2)->getSimpleValueType(0);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
unsigned CurOp = 2;
SmallVector<SDValue, 8> Operands;
Operands.push_back(Node->getOperand(CurOp++)); // Store value.
addVectorLoadStoreOperands(Node, Log2SEW, DL, CurOp, IsMasked, IsStrided,
Operands);
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
const RISCV::VSEPseudo *P = RISCV::getVSEPseudo(
IsMasked, IsStrided, Log2SEW, static_cast<unsigned>(LMUL));
MachineSDNode *Store =
CurDAG->getMachineNode(P->Pseudo, DL, Node->getVTList(), Operands);
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Store, {MemOp->getMemOperand()});
ReplaceNode(Node, Store);
return;
}
}
break;
}
case ISD::BITCAST: {
MVT SrcVT = Node->getOperand(0).getSimpleValueType();
// Just drop bitcasts between vectors if both are fixed or both are
// scalable.
if ((VT.isScalableVector() && SrcVT.isScalableVector()) ||
(VT.isFixedLengthVector() && SrcVT.isFixedLengthVector())) {
ReplaceUses(SDValue(Node, 0), Node->getOperand(0));
CurDAG->RemoveDeadNode(Node);
return;
}
break;
}
case ISD::INSERT_SUBVECTOR: {
SDValue V = Node->getOperand(0);
SDValue SubV = Node->getOperand(1);
SDLoc DL(SubV);
auto Idx = Node->getConstantOperandVal(2);
MVT SubVecVT = SubV.getSimpleValueType();
const RISCVTargetLowering &TLI = *Subtarget->getTargetLowering();
MVT SubVecContainerVT = SubVecVT;
// Establish the correct scalable-vector types for any fixed-length type.
if (SubVecVT.isFixedLengthVector())
SubVecContainerVT = TLI.getContainerForFixedLengthVector(SubVecVT);
if (VT.isFixedLengthVector())
VT = TLI.getContainerForFixedLengthVector(VT);
const auto *TRI = Subtarget->getRegisterInfo();
unsigned SubRegIdx;
std::tie(SubRegIdx, Idx) =
RISCVTargetLowering::decomposeSubvectorInsertExtractToSubRegs(
VT, SubVecContainerVT, Idx, TRI);
// If the Idx hasn't been completely eliminated then this is a subvector
// insert which doesn't naturally align to a vector register. These must
// be handled using instructions to manipulate the vector registers.
if (Idx != 0)
break;
RISCVII::VLMUL SubVecLMUL = RISCVTargetLowering::getLMUL(SubVecContainerVT);
bool IsSubVecPartReg = SubVecLMUL == RISCVII::VLMUL::LMUL_F2 ||
SubVecLMUL == RISCVII::VLMUL::LMUL_F4 ||
SubVecLMUL == RISCVII::VLMUL::LMUL_F8;
(void)IsSubVecPartReg; // Silence unused variable warning without asserts.
assert((!IsSubVecPartReg || V.isUndef()) &&
"Expecting lowering to have created legal INSERT_SUBVECTORs when "
"the subvector is smaller than a full-sized register");
// If we haven't set a SubRegIdx, then we must be going between
// equally-sized LMUL groups (e.g. VR -> VR). This can be done as a copy.
if (SubRegIdx == RISCV::NoSubRegister) {
unsigned InRegClassID = RISCVTargetLowering::getRegClassIDForVecVT(VT);
assert(RISCVTargetLowering::getRegClassIDForVecVT(SubVecContainerVT) ==
InRegClassID &&
"Unexpected subvector extraction");
SDValue RC = CurDAG->getTargetConstant(InRegClassID, DL, XLenVT);
SDNode *NewNode = CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS,
DL, VT, SubV, RC);
ReplaceNode(Node, NewNode);
return;
}
SDValue Insert = CurDAG->getTargetInsertSubreg(SubRegIdx, DL, VT, V, SubV);
ReplaceNode(Node, Insert.getNode());
return;
}
case ISD::EXTRACT_SUBVECTOR: {
SDValue V = Node->getOperand(0);
auto Idx = Node->getConstantOperandVal(1);
MVT InVT = V.getSimpleValueType();
SDLoc DL(V);
const RISCVTargetLowering &TLI = *Subtarget->getTargetLowering();
MVT SubVecContainerVT = VT;
// Establish the correct scalable-vector types for any fixed-length type.
if (VT.isFixedLengthVector())
SubVecContainerVT = TLI.getContainerForFixedLengthVector(VT);
if (InVT.isFixedLengthVector())
InVT = TLI.getContainerForFixedLengthVector(InVT);
const auto *TRI = Subtarget->getRegisterInfo();
unsigned SubRegIdx;
std::tie(SubRegIdx, Idx) =
RISCVTargetLowering::decomposeSubvectorInsertExtractToSubRegs(
InVT, SubVecContainerVT, Idx, TRI);
// If the Idx hasn't been completely eliminated then this is a subvector
// extract which doesn't naturally align to a vector register. These must
// be handled using instructions to manipulate the vector registers.
if (Idx != 0)
break;
// If we haven't set a SubRegIdx, then we must be going between
// equally-sized LMUL types (e.g. VR -> VR). This can be done as a copy.
if (SubRegIdx == RISCV::NoSubRegister) {
unsigned InRegClassID = RISCVTargetLowering::getRegClassIDForVecVT(InVT);
assert(RISCVTargetLowering::getRegClassIDForVecVT(SubVecContainerVT) ==
InRegClassID &&
"Unexpected subvector extraction");
SDValue RC = CurDAG->getTargetConstant(InRegClassID, DL, XLenVT);
SDNode *NewNode =
CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, DL, VT, V, RC);
ReplaceNode(Node, NewNode);
return;
}
SDValue Extract = CurDAG->getTargetExtractSubreg(SubRegIdx, DL, VT, V);
ReplaceNode(Node, Extract.getNode());
return;
}
case RISCVISD::VMV_V_X_VL:
case RISCVISD::VFMV_V_F_VL: {
// Try to match splat of a scalar load to a strided load with stride of x0.
SDValue Src = Node->getOperand(0);
auto *Ld = dyn_cast<LoadSDNode>(Src);
if (!Ld)
break;
EVT MemVT = Ld->getMemoryVT();
// The memory VT should be the same size as the element type.
if (MemVT.getStoreSize() != VT.getVectorElementType().getStoreSize())
break;
if (!IsProfitableToFold(Src, Node, Node) ||
!IsLegalToFold(Src, Node, Node, TM.getOptLevel()))
break;
SDValue VL;
selectVLOp(Node->getOperand(1), VL);
unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits());
SDValue SEW = CurDAG->getTargetConstant(Log2SEW, DL, XLenVT);
SDValue Operands[] = {Ld->getBasePtr(),
CurDAG->getRegister(RISCV::X0, XLenVT), VL, SEW,
Ld->getChain()};
RISCVII::VLMUL LMUL = RISCVTargetLowering::getLMUL(VT);
const RISCV::VLEPseudo *P = RISCV::getVLEPseudo(
/*IsMasked*/ false, /*IsStrided*/ true, /*FF*/ false, Log2SEW,
static_cast<unsigned>(LMUL));
MachineSDNode *Load =
CurDAG->getMachineNode(P->Pseudo, DL, Node->getVTList(), Operands);
if (auto *MemOp = dyn_cast<MemSDNode>(Node))
CurDAG->setNodeMemRefs(Load, {MemOp->getMemOperand()});
ReplaceNode(Node, Load);
return;
}
}
// Select the default instruction.
SelectCode(Node);
}
bool RISCVDAGToDAGISel::SelectInlineAsmMemoryOperand(
const SDValue &Op, unsigned ConstraintID, std::vector<SDValue> &OutOps) {
switch (ConstraintID) {
case InlineAsm::Constraint_m:
// We just support simple memory operands that have a single address
// operand and need no special handling.
OutOps.push_back(Op);
return false;
case InlineAsm::Constraint_A:
OutOps.push_back(Op);
return false;
default:
break;
}
return true;
}
bool RISCVDAGToDAGISel::SelectAddrFI(SDValue Addr, SDValue &Base) {
if (auto *FIN = dyn_cast<FrameIndexSDNode>(Addr)) {
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), Subtarget->getXLenVT());
return true;
}
return false;
}
bool RISCVDAGToDAGISel::SelectBaseAddr(SDValue Addr, SDValue &Base) {
// If this is FrameIndex, select it directly. Otherwise just let it get
// selected to a register independently.
if (auto *FIN = dyn_cast<FrameIndexSDNode>(Addr))
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), Subtarget->getXLenVT());
else
Base = Addr;
return true;
}
bool RISCVDAGToDAGISel::selectShiftMask(SDValue N, unsigned ShiftWidth,
SDValue &ShAmt) {
// Shift instructions on RISCV only read the lower 5 or 6 bits of the shift
// amount. If there is an AND on the shift amount, we can bypass it if it
// doesn't affect any of those bits.
if (N.getOpcode() == ISD::AND && isa<ConstantSDNode>(N.getOperand(1))) {
const APInt &AndMask = N->getConstantOperandAPInt(1);
// Since the max shift amount is a power of 2 we can subtract 1 to make a
// mask that covers the bits needed to represent all shift amounts.
assert(isPowerOf2_32(ShiftWidth) && "Unexpected max shift amount!");
APInt ShMask(AndMask.getBitWidth(), ShiftWidth - 1);
if (ShMask.isSubsetOf(AndMask)) {
ShAmt = N.getOperand(0);
return true;
}
// SimplifyDemandedBits may have optimized the mask so try restoring any
// bits that are known zero.
KnownBits Known = CurDAG->computeKnownBits(N->getOperand(0));
if (ShMask.isSubsetOf(AndMask | Known.Zero)) {
ShAmt = N.getOperand(0);
return true;
}
}
ShAmt = N;
return true;
}
bool RISCVDAGToDAGISel::selectSExti32(SDValue N, SDValue &Val) {
if (N.getOpcode() == ISD::SIGN_EXTEND_INREG &&
cast<VTSDNode>(N.getOperand(1))->getVT() == MVT::i32) {
Val = N.getOperand(0);
return true;
}
MVT VT = N.getSimpleValueType();
if (CurDAG->ComputeNumSignBits(N) > (VT.getSizeInBits() - 32)) {
Val = N;
return true;
}
return false;
}
bool RISCVDAGToDAGISel::selectZExti32(SDValue N, SDValue &Val) {
if (N.getOpcode() == ISD::AND) {
auto *C = dyn_cast<ConstantSDNode>(N.getOperand(1));
if (C && C->getZExtValue() == UINT64_C(0xFFFFFFFF)) {
Val = N.getOperand(0);
return true;
}
}
MVT VT = N.getSimpleValueType();
APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(), 32);
if (CurDAG->MaskedValueIsZero(N, Mask)) {
Val = N;
return true;
}
return false;
}
// Return true if all users of this SDNode* only consume the lower \p Bits.
// This can be used to form W instructions for add/sub/mul/shl even when the
// root isn't a sext_inreg. This can allow the ADDW/SUBW/MULW/SLLIW to CSE if
// SimplifyDemandedBits has made it so some users see a sext_inreg and some
// don't. The sext_inreg+add/sub/mul/shl will get selected, but still leave
// the add/sub/mul/shl to become non-W instructions. By checking the users we
// may be able to use a W instruction and CSE with the other instruction if
// this has happened. We could try to detect that the CSE opportunity exists
// before doing this, but that would be more complicated.
// TODO: Does this need to look through AND/OR/XOR to their users to find more
// opportunities.
bool RISCVDAGToDAGISel::hasAllNBitUsers(SDNode *Node, unsigned Bits) const {
assert((Node->getOpcode() == ISD::ADD || Node->getOpcode() == ISD::SUB ||
Node->getOpcode() == ISD::MUL || Node->getOpcode() == ISD::SHL ||
Node->getOpcode() == ISD::SRL ||
Node->getOpcode() == ISD::SIGN_EXTEND_INREG ||
isa<ConstantSDNode>(Node)) &&
"Unexpected opcode");
for (auto UI = Node->use_begin(), UE = Node->use_end(); UI != UE; ++UI) {
SDNode *User = *UI;
// Users of this node should have already been instruction selected
if (!User->isMachineOpcode())
return false;
// TODO: Add more opcodes?
switch (User->getMachineOpcode()) {
default:
return false;
case RISCV::ADDW:
case RISCV::ADDIW:
case RISCV::SUBW:
case RISCV::MULW:
case RISCV::SLLW:
case RISCV::SLLIW:
case RISCV::SRAW:
case RISCV::SRAIW:
case RISCV::SRLW:
case RISCV::SRLIW:
case RISCV::DIVW:
case RISCV::DIVUW:
case RISCV::REMW:
case RISCV::REMUW:
case RISCV::ROLW:
case RISCV::RORW:
case RISCV::RORIW:
case RISCV::CLZW:
case RISCV::CTZW:
case RISCV::CPOPW:
case RISCV::SLLIUW:
case RISCV::FCVT_H_W:
case RISCV::FCVT_H_WU:
case RISCV::FCVT_S_W:
case RISCV::FCVT_S_WU:
case RISCV::FCVT_D_W:
case RISCV::FCVT_D_WU:
if (Bits < 32)
return false;
break;
case RISCV::SLLI:
// SLLI only uses the lower (XLen - ShAmt) bits.
if (Bits < Subtarget->getXLen() - User->getConstantOperandVal(1))
return false;
break;
case RISCV::ADDUW:
case RISCV::SH1ADDUW:
case RISCV::SH2ADDUW:
case RISCV::SH3ADDUW:
// The first operand to add.uw/shXadd.uw is implicitly zero extended from
// 32 bits.
if (UI.getOperandNo() != 0 || Bits < 32)
return false;
break;
case RISCV::SB:
if (UI.getOperandNo() != 0 || Bits < 8)
return false;
break;
case RISCV::SH:
if (UI.getOperandNo() != 0 || Bits < 16)
return false;
break;
case RISCV::SW:
if (UI.getOperandNo() != 0 || Bits < 32)
return false;
break;
}
}
return true;
}
// Select VL as a 5 bit immediate or a value that will become a register. This
// allows us to choose betwen VSETIVLI or VSETVLI later.
bool RISCVDAGToDAGISel::selectVLOp(SDValue N, SDValue &VL) {
auto *C = dyn_cast<ConstantSDNode>(N);
if (C && isUInt<5>(C->getZExtValue()))
VL = CurDAG->getTargetConstant(C->getZExtValue(), SDLoc(N),
N->getValueType(0));
else
VL = N;
return true;
}
bool RISCVDAGToDAGISel::selectVSplat(SDValue N, SDValue &SplatVal) {
if (N.getOpcode() != ISD::SPLAT_VECTOR &&
N.getOpcode() != RISCVISD::SPLAT_VECTOR_I64 &&
N.getOpcode() != RISCVISD::VMV_V_X_VL)
return false;
SplatVal = N.getOperand(0);
return true;
}
using ValidateFn = bool (*)(int64_t);
static bool selectVSplatSimmHelper(SDValue N, SDValue &SplatVal,
SelectionDAG &DAG,
const RISCVSubtarget &Subtarget,
ValidateFn ValidateImm) {
if ((N.getOpcode() != ISD::SPLAT_VECTOR &&
N.getOpcode() != RISCVISD::SPLAT_VECTOR_I64 &&
N.getOpcode() != RISCVISD::VMV_V_X_VL) ||
!isa<ConstantSDNode>(N.getOperand(0)))
return false;
int64_t SplatImm = cast<ConstantSDNode>(N.getOperand(0))->getSExtValue();
// ISD::SPLAT_VECTOR, RISCVISD::SPLAT_VECTOR_I64 and RISCVISD::VMV_V_X_VL
// share semantics when the operand type is wider than the resulting vector
// element type: an implicit truncation first takes place. Therefore, perform
// a manual truncation/sign-extension in order to ignore any truncated bits
// and catch any zero-extended immediate.
// For example, we wish to match (i8 -1) -> (XLenVT 255) as a simm5 by first
// sign-extending to (XLenVT -1).
MVT XLenVT = Subtarget.getXLenVT();
assert(XLenVT == N.getOperand(0).getSimpleValueType() &&
"Unexpected splat operand type");
MVT EltVT = N.getSimpleValueType().getVectorElementType();
if (EltVT.bitsLT(XLenVT))
SplatImm = SignExtend64(SplatImm, EltVT.getSizeInBits());
if (!ValidateImm(SplatImm))
return false;
SplatVal = DAG.getTargetConstant(SplatImm, SDLoc(N), XLenVT);
return true;
}
bool RISCVDAGToDAGISel::selectVSplatSimm5(SDValue N, SDValue &SplatVal) {
return selectVSplatSimmHelper(N, SplatVal, *CurDAG, *Subtarget,
[](int64_t Imm) { return isInt<5>(Imm); });
}
bool RISCVDAGToDAGISel::selectVSplatSimm5Plus1(SDValue N, SDValue &SplatVal) {
return selectVSplatSimmHelper(
N, SplatVal, *CurDAG, *Subtarget,
[](int64_t Imm) { return (isInt<5>(Imm) && Imm != -16) || Imm == 16; });
}
bool RISCVDAGToDAGISel::selectVSplatSimm5Plus1NonZero(SDValue N,
SDValue &SplatVal) {
return selectVSplatSimmHelper(
N, SplatVal, *CurDAG, *Subtarget, [](int64_t Imm) {
return Imm != 0 && ((isInt<5>(Imm) && Imm != -16) || Imm == 16);
});
}
bool RISCVDAGToDAGISel::selectVSplatUimm5(SDValue N, SDValue &SplatVal) {
if ((N.getOpcode() != ISD::SPLAT_VECTOR &&
N.getOpcode() != RISCVISD::SPLAT_VECTOR_I64 &&
N.getOpcode() != RISCVISD::VMV_V_X_VL) ||
!isa<ConstantSDNode>(N.getOperand(0)))
return false;
int64_t SplatImm = cast<ConstantSDNode>(N.getOperand(0))->getSExtValue();
if (!isUInt<5>(SplatImm))
return false;
SplatVal =
CurDAG->getTargetConstant(SplatImm, SDLoc(N), Subtarget->getXLenVT());
return true;
}
bool RISCVDAGToDAGISel::selectRVVSimm5(SDValue N, unsigned Width,
SDValue &Imm) {
if (auto *C = dyn_cast<ConstantSDNode>(N)) {
int64_t ImmVal = SignExtend64(C->getSExtValue(), Width);
if (!isInt<5>(ImmVal))
return false;
Imm = CurDAG->getTargetConstant(ImmVal, SDLoc(N), Subtarget->getXLenVT());
return true;
}
return false;
}
// Merge an ADDI into the offset of a load/store instruction where possible.
// (load (addi base, off1), off2) -> (load base, off1+off2)
// (store val, (addi base, off1), off2) -> (store val, base, off1+off2)
// This is possible when off1+off2 fits a 12-bit immediate.
bool RISCVDAGToDAGISel::doPeepholeLoadStoreADDI(SDNode *N) {
int OffsetOpIdx;
int BaseOpIdx;
// Only attempt this optimisation for I-type loads and S-type stores.
switch (N->getMachineOpcode()) {
default:
return false;
case RISCV::LB:
case RISCV::LH:
case RISCV::LW:
case RISCV::LBU:
case RISCV::LHU:
case RISCV::LWU:
case RISCV::LD:
case RISCV::FLH:
case RISCV::FLW:
case RISCV::FLD:
BaseOpIdx = 0;
OffsetOpIdx = 1;
break;
case RISCV::SB:
case RISCV::SH:
case RISCV::SW:
case RISCV::SD:
case RISCV::FSH:
case RISCV::FSW:
case RISCV::FSD:
BaseOpIdx = 1;
OffsetOpIdx = 2;
break;
}
if (!isa<ConstantSDNode>(N->getOperand(OffsetOpIdx)))
return false;
SDValue Base = N->getOperand(BaseOpIdx);
// If the base is an ADDI, we can merge it in to the load/store.
if (!Base.isMachineOpcode() || Base.getMachineOpcode() != RISCV::ADDI)
return false;
SDValue ImmOperand = Base.getOperand(1);
uint64_t Offset2 = N->getConstantOperandVal(OffsetOpIdx);
if (auto *Const = dyn_cast<ConstantSDNode>(ImmOperand)) {
int64_t Offset1 = Const->getSExtValue();
int64_t CombinedOffset = Offset1 + Offset2;
if (!isInt<12>(CombinedOffset))
return false;
ImmOperand = CurDAG->getTargetConstant(CombinedOffset, SDLoc(ImmOperand),
ImmOperand.getValueType());
} else if (auto *GA = dyn_cast<GlobalAddressSDNode>(ImmOperand)) {
// If the off1 in (addi base, off1) is a global variable's address (its
// low part, really), then we can rely on the alignment of that variable
// to provide a margin of safety before off1 can overflow the 12 bits.
// Check if off2 falls within that margin; if so off1+off2 can't overflow.
const DataLayout &DL = CurDAG->getDataLayout();
Align Alignment = GA->getGlobal()->getPointerAlignment(DL);
if (Offset2 != 0 && Alignment <= Offset2)
return false;
int64_t Offset1 = GA->getOffset();
int64_t CombinedOffset = Offset1 + Offset2;
ImmOperand = CurDAG->getTargetGlobalAddress(
GA->getGlobal(), SDLoc(ImmOperand), ImmOperand.getValueType(),
CombinedOffset, GA->getTargetFlags());
} else if (auto *CP = dyn_cast<ConstantPoolSDNode>(ImmOperand)) {
// Ditto.
Align Alignment = CP->getAlign();
if (Offset2 != 0 && Alignment <= Offset2)
return false;
int64_t Offset1 = CP->getOffset();
int64_t CombinedOffset = Offset1 + Offset2;
ImmOperand = CurDAG->getTargetConstantPool(
CP->getConstVal(), ImmOperand.getValueType(), CP->getAlign(),
CombinedOffset, CP->getTargetFlags());
} else {
return false;
}
LLVM_DEBUG(dbgs() << "Folding add-immediate into mem-op:\nBase: ");
LLVM_DEBUG(Base->dump(CurDAG));
LLVM_DEBUG(dbgs() << "\nN: ");
LLVM_DEBUG(N->dump(CurDAG));
LLVM_DEBUG(dbgs() << "\n");
// Modify the offset operand of the load/store.
if (BaseOpIdx == 0) // Load
CurDAG->UpdateNodeOperands(N, Base.getOperand(0), ImmOperand,
N->getOperand(2));
else // Store
CurDAG->UpdateNodeOperands(N, N->getOperand(0), Base.getOperand(0),
ImmOperand, N->getOperand(3));
return true;
}
// Try to remove sext.w if the input is a W instruction or can be made into
// a W instruction cheaply.
bool RISCVDAGToDAGISel::doPeepholeSExtW(SDNode *N) {
// Look for the sext.w pattern, addiw rd, rs1, 0.
if (N->getMachineOpcode() != RISCV::ADDIW ||
!isNullConstant(N->getOperand(1)))
return false;
SDValue N0 = N->getOperand(0);
if (!N0.isMachineOpcode())
return false;
switch (N0.getMachineOpcode()) {
default:
break;
case RISCV::ADD:
case RISCV::ADDI:
case RISCV::SUB:
case RISCV::MUL:
case RISCV::SLLI: {
// Convert sext.w+add/sub/mul to their W instructions. This will create
// a new independent instruction. This improves latency.
unsigned Opc;
switch (N0.getMachineOpcode()) {
default:
llvm_unreachable("Unexpected opcode!");
case RISCV::ADD: Opc = RISCV::ADDW; break;
case RISCV::ADDI: Opc = RISCV::ADDIW; break;
case RISCV::SUB: Opc = RISCV::SUBW; break;
case RISCV::MUL: Opc = RISCV::MULW; break;
case RISCV::SLLI: Opc = RISCV::SLLIW; break;
}
SDValue N00 = N0.getOperand(0);
SDValue N01 = N0.getOperand(1);
// Shift amount needs to be uimm5.
if (N0.getMachineOpcode() == RISCV::SLLI &&
!isUInt<5>(cast<ConstantSDNode>(N01)->getSExtValue()))
break;
SDNode *Result =
CurDAG->getMachineNode(Opc, SDLoc(N), N->getValueType(0),
N00, N01);
ReplaceUses(N, Result);
return true;
}
case RISCV::ADDW:
case RISCV::ADDIW:
case RISCV::SUBW:
case RISCV::MULW:
case RISCV::SLLIW:
// Result is already sign extended just remove the sext.w.
// NOTE: We only handle the nodes that are selected with hasAllWUsers.
ReplaceUses(N, N0.getNode());
return true;
}
return false;
}
// This pass converts a legalized DAG into a RISCV-specific DAG, ready
// for instruction scheduling.
FunctionPass *llvm::createRISCVISelDag(RISCVTargetMachine &TM) {
return new RISCVDAGToDAGISel(TM);
}