//===- RISCVVIntrinsicUtils.cpp - RISC-V Vector Intrinsic Utils -*- C++ -*-===//
//
// 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
//
//===----------------------------------------------------------------------===//

#include "clang/Support/RISCVVIntrinsicUtils.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include <numeric>
#include <optional>

using namespace llvm;

namespace clang {
namespace RISCV {

const PrototypeDescriptor PrototypeDescriptor::Mask = PrototypeDescriptor(
    BaseTypeModifier::Vector, VectorTypeModifier::MaskVector);
const PrototypeDescriptor PrototypeDescriptor::VL =
    PrototypeDescriptor(BaseTypeModifier::SizeT);
const PrototypeDescriptor PrototypeDescriptor::Vector =
    PrototypeDescriptor(BaseTypeModifier::Vector);

//===----------------------------------------------------------------------===//
// Type implementation
//===----------------------------------------------------------------------===//

LMULType::LMULType(int NewLog2LMUL) {
  // Check Log2LMUL is -3, -2, -1, 0, 1, 2, 3
  assert(NewLog2LMUL <= 3 && NewLog2LMUL >= -3 && "Bad LMUL number!");
  Log2LMUL = NewLog2LMUL;
}

std::string LMULType::str() const {
  if (Log2LMUL < 0)
    return "mf" + utostr(1ULL << (-Log2LMUL));
  return "m" + utostr(1ULL << Log2LMUL);
}

VScaleVal LMULType::getScale(unsigned ElementBitwidth) const {
  int Log2ScaleResult = 0;
  switch (ElementBitwidth) {
  default:
    break;
  case 8:
    Log2ScaleResult = Log2LMUL + 3;
    break;
  case 16:
    Log2ScaleResult = Log2LMUL + 2;
    break;
  case 32:
    Log2ScaleResult = Log2LMUL + 1;
    break;
  case 64:
    Log2ScaleResult = Log2LMUL;
    break;
  }
  // Illegal vscale result would be less than 1
  if (Log2ScaleResult < 0)
    return std::nullopt;
  return 1 << Log2ScaleResult;
}

void LMULType::MulLog2LMUL(int log2LMUL) { Log2LMUL += log2LMUL; }

RVVType::RVVType(BasicType BT, int Log2LMUL,
                 const PrototypeDescriptor &prototype)
    : BT(BT), LMUL(LMULType(Log2LMUL)) {
  applyBasicType();
  applyModifier(prototype);
  Valid = verifyType();
  if (Valid) {
    initBuiltinStr();
    initTypeStr();
    if (isVector()) {
      initClangBuiltinStr();
    }
  }
}

// clang-format off
// boolean type are encoded the ratio of n (SEW/LMUL)
// SEW/LMUL | 1         | 2         | 4         | 8        | 16        | 32        | 64
// c type   | vbool64_t | vbool32_t | vbool16_t | vbool8_t | vbool4_t  | vbool2_t  | vbool1_t
// IR type  | nxv1i1    | nxv2i1    | nxv4i1    | nxv8i1   | nxv16i1   | nxv32i1   | nxv64i1

// type\lmul | 1/8    | 1/4      | 1/2     | 1       | 2        | 4        | 8
// --------  |------  | -------- | ------- | ------- | -------- | -------- | --------
// i64       | N/A    | N/A      | N/A     | nxv1i64 | nxv2i64  | nxv4i64  | nxv8i64
// i32       | N/A    | N/A      | nxv1i32 | nxv2i32 | nxv4i32  | nxv8i32  | nxv16i32
// i16       | N/A    | nxv1i16  | nxv2i16 | nxv4i16 | nxv8i16  | nxv16i16 | nxv32i16
// i8        | nxv1i8 | nxv2i8   | nxv4i8  | nxv8i8  | nxv16i8  | nxv32i8  | nxv64i8
// double    | N/A    | N/A      | N/A     | nxv1f64 | nxv2f64  | nxv4f64  | nxv8f64
// float     | N/A    | N/A      | nxv1f32 | nxv2f32 | nxv4f32  | nxv8f32  | nxv16f32
// half      | N/A    | nxv1f16  | nxv2f16 | nxv4f16 | nxv8f16  | nxv16f16 | nxv32f16
// bfloat16  | N/A    | nxv1bf16 | nxv2bf16| nxv4bf16| nxv8bf16 | nxv16bf16| nxv32bf16
// clang-format on

bool RVVType::verifyType() const {
  if (ScalarType == Invalid)
    return false;
  if (isScalar())
    return true;
  if (!Scale)
    return false;
  if (isFloat() && ElementBitwidth == 8)
    return false;
  if (isBFloat() && ElementBitwidth != 16)
    return false;
  if (IsTuple && (NF == 1 || NF > 8))
    return false;
  if (IsTuple && (1 << std::max(0, LMUL.Log2LMUL)) * NF > 8)
    return false;
  unsigned V = *Scale;
  switch (ElementBitwidth) {
  case 1:
  case 8:
    // Check Scale is 1,2,4,8,16,32,64
    return (V <= 64 && isPowerOf2_32(V));
  case 16:
    // Check Scale is 1,2,4,8,16,32
    return (V <= 32 && isPowerOf2_32(V));
  case 32:
    // Check Scale is 1,2,4,8,16
    return (V <= 16 && isPowerOf2_32(V));
  case 64:
    // Check Scale is 1,2,4,8
    return (V <= 8 && isPowerOf2_32(V));
  }
  return false;
}

void RVVType::initBuiltinStr() {
  assert(isValid() && "RVVType is invalid");
  switch (ScalarType) {
  case ScalarTypeKind::Void:
    BuiltinStr = "v";
    return;
  case ScalarTypeKind::Size_t:
    BuiltinStr = "z";
    if (IsImmediate)
      BuiltinStr = "I" + BuiltinStr;
    if (IsPointer)
      BuiltinStr += "*";
    return;
  case ScalarTypeKind::Ptrdiff_t:
    BuiltinStr = "Y";
    return;
  case ScalarTypeKind::UnsignedLong:
    BuiltinStr = "ULi";
    return;
  case ScalarTypeKind::SignedLong:
    BuiltinStr = "Li";
    return;
  case ScalarTypeKind::Boolean:
    assert(ElementBitwidth == 1);
    BuiltinStr += "b";
    break;
  case ScalarTypeKind::SignedInteger:
  case ScalarTypeKind::UnsignedInteger:
    switch (ElementBitwidth) {
    case 8:
      BuiltinStr += "c";
      break;
    case 16:
      BuiltinStr += "s";
      break;
    case 32:
      BuiltinStr += "i";
      break;
    case 64:
      BuiltinStr += "Wi";
      break;
    default:
      llvm_unreachable("Unhandled ElementBitwidth!");
    }
    if (isSignedInteger())
      BuiltinStr = "S" + BuiltinStr;
    else
      BuiltinStr = "U" + BuiltinStr;
    break;
  case ScalarTypeKind::Float:
    switch (ElementBitwidth) {
    case 16:
      BuiltinStr += "x";
      break;
    case 32:
      BuiltinStr += "f";
      break;
    case 64:
      BuiltinStr += "d";
      break;
    default:
      llvm_unreachable("Unhandled ElementBitwidth!");
    }
    break;
  case ScalarTypeKind::BFloat:
    BuiltinStr += "y";
    break;
  default:
    llvm_unreachable("ScalarType is invalid!");
  }
  if (IsImmediate)
    BuiltinStr = "I" + BuiltinStr;
  if (isScalar()) {
    if (IsConstant)
      BuiltinStr += "C";
    if (IsPointer)
      BuiltinStr += "*";
    return;
  }
  BuiltinStr = "q" + utostr(*Scale) + BuiltinStr;
  // Pointer to vector types. Defined for segment load intrinsics.
  // segment load intrinsics have pointer type arguments to store the loaded
  // vector values.
  if (IsPointer)
    BuiltinStr += "*";

  if (IsTuple)
    BuiltinStr = "T" + utostr(NF) + BuiltinStr;
}

void RVVType::initClangBuiltinStr() {
  assert(isValid() && "RVVType is invalid");
  assert(isVector() && "Handle Vector type only");

  ClangBuiltinStr = "__rvv_";
  switch (ScalarType) {
  case ScalarTypeKind::Boolean:
    ClangBuiltinStr += "bool" + utostr(64 / *Scale) + "_t";
    return;
  case ScalarTypeKind::Float:
    ClangBuiltinStr += "float";
    break;
  case ScalarTypeKind::BFloat:
    ClangBuiltinStr += "bfloat";
    break;
  case ScalarTypeKind::SignedInteger:
    ClangBuiltinStr += "int";
    break;
  case ScalarTypeKind::UnsignedInteger:
    ClangBuiltinStr += "uint";
    break;
  default:
    llvm_unreachable("ScalarTypeKind is invalid");
  }
  ClangBuiltinStr += utostr(ElementBitwidth) + LMUL.str() +
                     (IsTuple ? "x" + utostr(NF) : "") + "_t";
}

void RVVType::initTypeStr() {
  assert(isValid() && "RVVType is invalid");

  if (IsConstant)
    Str += "const ";

  auto getTypeString = [&](StringRef TypeStr) {
    if (isScalar())
      return Twine(TypeStr + Twine(ElementBitwidth) + "_t").str();
    return Twine("v" + TypeStr + Twine(ElementBitwidth) + LMUL.str() +
                 (IsTuple ? "x" + utostr(NF) : "") + "_t")
        .str();
  };

  switch (ScalarType) {
  case ScalarTypeKind::Void:
    Str = "void";
    return;
  case ScalarTypeKind::Size_t:
    Str = "size_t";
    if (IsPointer)
      Str += " *";
    return;
  case ScalarTypeKind::Ptrdiff_t:
    Str = "ptrdiff_t";
    return;
  case ScalarTypeKind::UnsignedLong:
    Str = "unsigned long";
    return;
  case ScalarTypeKind::SignedLong:
    Str = "long";
    return;
  case ScalarTypeKind::Boolean:
    if (isScalar())
      Str += "bool";
    else
      // Vector bool is special case, the formulate is
      // `vbool<N>_t = MVT::nxv<64/N>i1` ex. vbool16_t = MVT::4i1
      Str += "vbool" + utostr(64 / *Scale) + "_t";
    break;
  case ScalarTypeKind::Float:
    if (isScalar()) {
      if (ElementBitwidth == 64)
        Str += "double";
      else if (ElementBitwidth == 32)
        Str += "float";
      else if (ElementBitwidth == 16)
        Str += "_Float16";
      else
        llvm_unreachable("Unhandled floating type.");
    } else
      Str += getTypeString("float");
    break;
  case ScalarTypeKind::BFloat:
    if (isScalar()) {
      if (ElementBitwidth == 16)
        Str += "__bf16";
      else
        llvm_unreachable("Unhandled floating type.");
    } else
      Str += getTypeString("bfloat");
    break;
  case ScalarTypeKind::SignedInteger:
    Str += getTypeString("int");
    break;
  case ScalarTypeKind::UnsignedInteger:
    Str += getTypeString("uint");
    break;
  default:
    llvm_unreachable("ScalarType is invalid!");
  }
  if (IsPointer)
    Str += " *";
}

void RVVType::initShortStr() {
  switch (ScalarType) {
  case ScalarTypeKind::Boolean:
    assert(isVector());
    ShortStr = "b" + utostr(64 / *Scale);
    return;
  case ScalarTypeKind::Float:
    ShortStr = "f" + utostr(ElementBitwidth);
    break;
  case ScalarTypeKind::BFloat:
    ShortStr = "bf" + utostr(ElementBitwidth);
    break;
  case ScalarTypeKind::SignedInteger:
    ShortStr = "i" + utostr(ElementBitwidth);
    break;
  case ScalarTypeKind::UnsignedInteger:
    ShortStr = "u" + utostr(ElementBitwidth);
    break;
  default:
    llvm_unreachable("Unhandled case!");
  }
  if (isVector())
    ShortStr += LMUL.str();
  if (isTuple())
    ShortStr += "x" + utostr(NF);
}

static VectorTypeModifier getTupleVTM(unsigned NF) {
  assert(2 <= NF && NF <= 8 && "2 <= NF <= 8");
  return static_cast<VectorTypeModifier>(
      static_cast<uint8_t>(VectorTypeModifier::Tuple2) + (NF - 2));
}

void RVVType::applyBasicType() {
  switch (BT) {
  case BasicType::Int8:
    ElementBitwidth = 8;
    ScalarType = ScalarTypeKind::SignedInteger;
    break;
  case BasicType::Int16:
    ElementBitwidth = 16;
    ScalarType = ScalarTypeKind::SignedInteger;
    break;
  case BasicType::Int32:
    ElementBitwidth = 32;
    ScalarType = ScalarTypeKind::SignedInteger;
    break;
  case BasicType::Int64:
    ElementBitwidth = 64;
    ScalarType = ScalarTypeKind::SignedInteger;
    break;
  case BasicType::Float16:
    ElementBitwidth = 16;
    ScalarType = ScalarTypeKind::Float;
    break;
  case BasicType::Float32:
    ElementBitwidth = 32;
    ScalarType = ScalarTypeKind::Float;
    break;
  case BasicType::Float64:
    ElementBitwidth = 64;
    ScalarType = ScalarTypeKind::Float;
    break;
  case BasicType::BFloat16:
    ElementBitwidth = 16;
    ScalarType = ScalarTypeKind::BFloat;
    break;
  default:
    llvm_unreachable("Unhandled type code!");
  }
  assert(ElementBitwidth != 0 && "Bad element bitwidth!");
}

std::optional<PrototypeDescriptor>
PrototypeDescriptor::parsePrototypeDescriptor(
    llvm::StringRef PrototypeDescriptorStr) {
  PrototypeDescriptor PD;
  BaseTypeModifier PT = BaseTypeModifier::Invalid;
  VectorTypeModifier VTM = VectorTypeModifier::NoModifier;

  if (PrototypeDescriptorStr.empty())
    return PD;

  // Handle base type modifier
  auto PType = PrototypeDescriptorStr.back();
  switch (PType) {
  case 'e':
    PT = BaseTypeModifier::Scalar;
    break;
  case 'v':
    PT = BaseTypeModifier::Vector;
    break;
  case 'w':
    PT = BaseTypeModifier::Vector;
    VTM = VectorTypeModifier::Widening2XVector;
    break;
  case 'q':
    PT = BaseTypeModifier::Vector;
    VTM = VectorTypeModifier::Widening4XVector;
    break;
  case 'o':
    PT = BaseTypeModifier::Vector;
    VTM = VectorTypeModifier::Widening8XVector;
    break;
  case 'm':
    PT = BaseTypeModifier::Vector;
    VTM = VectorTypeModifier::MaskVector;
    break;
  case '0':
    PT = BaseTypeModifier::Void;
    break;
  case 'z':
    PT = BaseTypeModifier::SizeT;
    break;
  case 't':
    PT = BaseTypeModifier::Ptrdiff;
    break;
  case 'u':
    PT = BaseTypeModifier::UnsignedLong;
    break;
  case 'l':
    PT = BaseTypeModifier::SignedLong;
    break;
  case 'f':
    PT = BaseTypeModifier::Float32;
    break;
  default:
    llvm_unreachable("Illegal primitive type transformers!");
  }
  PD.PT = static_cast<uint8_t>(PT);
  PrototypeDescriptorStr = PrototypeDescriptorStr.drop_back();

  // Compute the vector type transformers, it can only appear one time.
  if (PrototypeDescriptorStr.starts_with("(")) {
    assert(VTM == VectorTypeModifier::NoModifier &&
           "VectorTypeModifier should only have one modifier");
    size_t Idx = PrototypeDescriptorStr.find(')');
    assert(Idx != StringRef::npos);
    StringRef ComplexType = PrototypeDescriptorStr.slice(1, Idx);
    PrototypeDescriptorStr = PrototypeDescriptorStr.drop_front(Idx + 1);
    assert(!PrototypeDescriptorStr.contains('(') &&
           "Only allow one vector type modifier");

    auto ComplexTT = ComplexType.split(":");
    if (ComplexTT.first == "Log2EEW") {
      uint32_t Log2EEW;
      if (ComplexTT.second.getAsInteger(10, Log2EEW)) {
        llvm_unreachable("Invalid Log2EEW value!");
        return std::nullopt;
      }
      switch (Log2EEW) {
      case 3:
        VTM = VectorTypeModifier::Log2EEW3;
        break;
      case 4:
        VTM = VectorTypeModifier::Log2EEW4;
        break;
      case 5:
        VTM = VectorTypeModifier::Log2EEW5;
        break;
      case 6:
        VTM = VectorTypeModifier::Log2EEW6;
        break;
      default:
        llvm_unreachable("Invalid Log2EEW value, should be [3-6]");
        return std::nullopt;
      }
    } else if (ComplexTT.first == "FixedSEW") {
      uint32_t NewSEW;
      if (ComplexTT.second.getAsInteger(10, NewSEW)) {
        llvm_unreachable("Invalid FixedSEW value!");
        return std::nullopt;
      }
      switch (NewSEW) {
      case 8:
        VTM = VectorTypeModifier::FixedSEW8;
        break;
      case 16:
        VTM = VectorTypeModifier::FixedSEW16;
        break;
      case 32:
        VTM = VectorTypeModifier::FixedSEW32;
        break;
      case 64:
        VTM = VectorTypeModifier::FixedSEW64;
        break;
      default:
        llvm_unreachable("Invalid FixedSEW value, should be 8, 16, 32 or 64");
        return std::nullopt;
      }
    } else if (ComplexTT.first == "LFixedLog2LMUL") {
      int32_t Log2LMUL;
      if (ComplexTT.second.getAsInteger(10, Log2LMUL)) {
        llvm_unreachable("Invalid LFixedLog2LMUL value!");
        return std::nullopt;
      }
      switch (Log2LMUL) {
      case -3:
        VTM = VectorTypeModifier::LFixedLog2LMULN3;
        break;
      case -2:
        VTM = VectorTypeModifier::LFixedLog2LMULN2;
        break;
      case -1:
        VTM = VectorTypeModifier::LFixedLog2LMULN1;
        break;
      case 0:
        VTM = VectorTypeModifier::LFixedLog2LMUL0;
        break;
      case 1:
        VTM = VectorTypeModifier::LFixedLog2LMUL1;
        break;
      case 2:
        VTM = VectorTypeModifier::LFixedLog2LMUL2;
        break;
      case 3:
        VTM = VectorTypeModifier::LFixedLog2LMUL3;
        break;
      default:
        llvm_unreachable("Invalid LFixedLog2LMUL value, should be [-3, 3]");
        return std::nullopt;
      }
    } else if (ComplexTT.first == "SFixedLog2LMUL") {
      int32_t Log2LMUL;
      if (ComplexTT.second.getAsInteger(10, Log2LMUL)) {
        llvm_unreachable("Invalid SFixedLog2LMUL value!");
        return std::nullopt;
      }
      switch (Log2LMUL) {
      case -3:
        VTM = VectorTypeModifier::SFixedLog2LMULN3;
        break;
      case -2:
        VTM = VectorTypeModifier::SFixedLog2LMULN2;
        break;
      case -1:
        VTM = VectorTypeModifier::SFixedLog2LMULN1;
        break;
      case 0:
        VTM = VectorTypeModifier::SFixedLog2LMUL0;
        break;
      case 1:
        VTM = VectorTypeModifier::SFixedLog2LMUL1;
        break;
      case 2:
        VTM = VectorTypeModifier::SFixedLog2LMUL2;
        break;
      case 3:
        VTM = VectorTypeModifier::SFixedLog2LMUL3;
        break;
      default:
        llvm_unreachable("Invalid LFixedLog2LMUL value, should be [-3, 3]");
        return std::nullopt;
      }

    } else if (ComplexTT.first == "SEFixedLog2LMUL") {
      int32_t Log2LMUL;
      if (ComplexTT.second.getAsInteger(10, Log2LMUL)) {
        llvm_unreachable("Invalid SEFixedLog2LMUL value!");
        return std::nullopt;
      }
      switch (Log2LMUL) {
      case -3:
        VTM = VectorTypeModifier::SEFixedLog2LMULN3;
        break;
      case -2:
        VTM = VectorTypeModifier::SEFixedLog2LMULN2;
        break;
      case -1:
        VTM = VectorTypeModifier::SEFixedLog2LMULN1;
        break;
      case 0:
        VTM = VectorTypeModifier::SEFixedLog2LMUL0;
        break;
      case 1:
        VTM = VectorTypeModifier::SEFixedLog2LMUL1;
        break;
      case 2:
        VTM = VectorTypeModifier::SEFixedLog2LMUL2;
        break;
      case 3:
        VTM = VectorTypeModifier::SEFixedLog2LMUL3;
        break;
      default:
        llvm_unreachable("Invalid LFixedLog2LMUL value, should be [-3, 3]");
        return std::nullopt;
      }
    } else if (ComplexTT.first == "Tuple") {
      unsigned NF = 0;
      if (ComplexTT.second.getAsInteger(10, NF)) {
        llvm_unreachable("Invalid NF value!");
        return std::nullopt;
      }
      VTM = getTupleVTM(NF);
    } else {
      llvm_unreachable("Illegal complex type transformers!");
    }
  }
  PD.VTM = static_cast<uint8_t>(VTM);

  // Compute the remain type transformers
  TypeModifier TM = TypeModifier::NoModifier;
  for (char I : PrototypeDescriptorStr) {
    switch (I) {
    case 'P':
      if ((TM & TypeModifier::Const) == TypeModifier::Const)
        llvm_unreachable("'P' transformer cannot be used after 'C'");
      if ((TM & TypeModifier::Pointer) == TypeModifier::Pointer)
        llvm_unreachable("'P' transformer cannot be used twice");
      TM |= TypeModifier::Pointer;
      break;
    case 'C':
      TM |= TypeModifier::Const;
      break;
    case 'K':
      TM |= TypeModifier::Immediate;
      break;
    case 'U':
      TM |= TypeModifier::UnsignedInteger;
      break;
    case 'I':
      TM |= TypeModifier::SignedInteger;
      break;
    case 'F':
      TM |= TypeModifier::Float;
      break;
    case 'S':
      TM |= TypeModifier::LMUL1;
      break;
    default:
      llvm_unreachable("Illegal non-primitive type transformer!");
    }
  }
  PD.TM = static_cast<uint8_t>(TM);

  return PD;
}

void RVVType::applyModifier(const PrototypeDescriptor &Transformer) {
  // Handle primitive type transformer
  switch (static_cast<BaseTypeModifier>(Transformer.PT)) {
  case BaseTypeModifier::Scalar:
    Scale = 0;
    break;
  case BaseTypeModifier::Vector:
    Scale = LMUL.getScale(ElementBitwidth);
    break;
  case BaseTypeModifier::Void:
    ScalarType = ScalarTypeKind::Void;
    break;
  case BaseTypeModifier::SizeT:
    ScalarType = ScalarTypeKind::Size_t;
    break;
  case BaseTypeModifier::Ptrdiff:
    ScalarType = ScalarTypeKind::Ptrdiff_t;
    break;
  case BaseTypeModifier::UnsignedLong:
    ScalarType = ScalarTypeKind::UnsignedLong;
    break;
  case BaseTypeModifier::SignedLong:
    ScalarType = ScalarTypeKind::SignedLong;
    break;
  case BaseTypeModifier::Float32:
    ElementBitwidth = 32;
    ScalarType = ScalarTypeKind::Float;
    break;
  case BaseTypeModifier::Invalid:
    ScalarType = ScalarTypeKind::Invalid;
    return;
  }

  switch (static_cast<VectorTypeModifier>(Transformer.VTM)) {
  case VectorTypeModifier::Widening2XVector:
    ElementBitwidth *= 2;
    LMUL.MulLog2LMUL(1);
    Scale = LMUL.getScale(ElementBitwidth);
    break;
  case VectorTypeModifier::Widening4XVector:
    ElementBitwidth *= 4;
    LMUL.MulLog2LMUL(2);
    Scale = LMUL.getScale(ElementBitwidth);
    break;
  case VectorTypeModifier::Widening8XVector:
    ElementBitwidth *= 8;
    LMUL.MulLog2LMUL(3);
    Scale = LMUL.getScale(ElementBitwidth);
    break;
  case VectorTypeModifier::MaskVector:
    ScalarType = ScalarTypeKind::Boolean;
    Scale = LMUL.getScale(ElementBitwidth);
    ElementBitwidth = 1;
    break;
  case VectorTypeModifier::Log2EEW3:
    applyLog2EEW(3);
    break;
  case VectorTypeModifier::Log2EEW4:
    applyLog2EEW(4);
    break;
  case VectorTypeModifier::Log2EEW5:
    applyLog2EEW(5);
    break;
  case VectorTypeModifier::Log2EEW6:
    applyLog2EEW(6);
    break;
  case VectorTypeModifier::FixedSEW8:
    applyFixedSEW(8);
    break;
  case VectorTypeModifier::FixedSEW16:
    applyFixedSEW(16);
    break;
  case VectorTypeModifier::FixedSEW32:
    applyFixedSEW(32);
    break;
  case VectorTypeModifier::FixedSEW64:
    applyFixedSEW(64);
    break;
  case VectorTypeModifier::LFixedLog2LMULN3:
    applyFixedLog2LMUL(-3, FixedLMULType::LargerThan);
    break;
  case VectorTypeModifier::LFixedLog2LMULN2:
    applyFixedLog2LMUL(-2, FixedLMULType::LargerThan);
    break;
  case VectorTypeModifier::LFixedLog2LMULN1:
    applyFixedLog2LMUL(-1, FixedLMULType::LargerThan);
    break;
  case VectorTypeModifier::LFixedLog2LMUL0:
    applyFixedLog2LMUL(0, FixedLMULType::LargerThan);
    break;
  case VectorTypeModifier::LFixedLog2LMUL1:
    applyFixedLog2LMUL(1, FixedLMULType::LargerThan);
    break;
  case VectorTypeModifier::LFixedLog2LMUL2:
    applyFixedLog2LMUL(2, FixedLMULType::LargerThan);
    break;
  case VectorTypeModifier::LFixedLog2LMUL3:
    applyFixedLog2LMUL(3, FixedLMULType::LargerThan);
    break;
  case VectorTypeModifier::SFixedLog2LMULN3:
    applyFixedLog2LMUL(-3, FixedLMULType::SmallerThan);
    break;
  case VectorTypeModifier::SFixedLog2LMULN2:
    applyFixedLog2LMUL(-2, FixedLMULType::SmallerThan);
    break;
  case VectorTypeModifier::SFixedLog2LMULN1:
    applyFixedLog2LMUL(-1, FixedLMULType::SmallerThan);
    break;
  case VectorTypeModifier::SFixedLog2LMUL0:
    applyFixedLog2LMUL(0, FixedLMULType::SmallerThan);
    break;
  case VectorTypeModifier::SFixedLog2LMUL1:
    applyFixedLog2LMUL(1, FixedLMULType::SmallerThan);
    break;
  case VectorTypeModifier::SFixedLog2LMUL2:
    applyFixedLog2LMUL(2, FixedLMULType::SmallerThan);
    break;
  case VectorTypeModifier::SFixedLog2LMUL3:
    applyFixedLog2LMUL(3, FixedLMULType::SmallerThan);
    break;
  case VectorTypeModifier::SEFixedLog2LMULN3:
    applyFixedLog2LMUL(-3, FixedLMULType::SmallerOrEqual);
    break;
  case VectorTypeModifier::SEFixedLog2LMULN2:
    applyFixedLog2LMUL(-2, FixedLMULType::SmallerOrEqual);
    break;
  case VectorTypeModifier::SEFixedLog2LMULN1:
    applyFixedLog2LMUL(-1, FixedLMULType::SmallerOrEqual);
    break;
  case VectorTypeModifier::SEFixedLog2LMUL0:
    applyFixedLog2LMUL(0, FixedLMULType::SmallerOrEqual);
    break;
  case VectorTypeModifier::SEFixedLog2LMUL1:
    applyFixedLog2LMUL(1, FixedLMULType::SmallerOrEqual);
    break;
  case VectorTypeModifier::SEFixedLog2LMUL2:
    applyFixedLog2LMUL(2, FixedLMULType::SmallerOrEqual);
    break;
  case VectorTypeModifier::SEFixedLog2LMUL3:
    applyFixedLog2LMUL(3, FixedLMULType::SmallerOrEqual);
    break;
  case VectorTypeModifier::Tuple2:
  case VectorTypeModifier::Tuple3:
  case VectorTypeModifier::Tuple4:
  case VectorTypeModifier::Tuple5:
  case VectorTypeModifier::Tuple6:
  case VectorTypeModifier::Tuple7:
  case VectorTypeModifier::Tuple8: {
    IsTuple = true;
    NF = 2 + static_cast<uint8_t>(Transformer.VTM) -
         static_cast<uint8_t>(VectorTypeModifier::Tuple2);
    break;
  }
  case VectorTypeModifier::NoModifier:
    break;
  }

  // Early return if the current type modifier is already invalid.
  if (ScalarType == Invalid)
    return;

  for (unsigned TypeModifierMaskShift = 0;
       TypeModifierMaskShift <= static_cast<unsigned>(TypeModifier::MaxOffset);
       ++TypeModifierMaskShift) {
    unsigned TypeModifierMask = 1 << TypeModifierMaskShift;
    if ((static_cast<unsigned>(Transformer.TM) & TypeModifierMask) !=
        TypeModifierMask)
      continue;
    switch (static_cast<TypeModifier>(TypeModifierMask)) {
    case TypeModifier::Pointer:
      IsPointer = true;
      break;
    case TypeModifier::Const:
      IsConstant = true;
      break;
    case TypeModifier::Immediate:
      IsImmediate = true;
      IsConstant = true;
      break;
    case TypeModifier::UnsignedInteger:
      ScalarType = ScalarTypeKind::UnsignedInteger;
      break;
    case TypeModifier::SignedInteger:
      ScalarType = ScalarTypeKind::SignedInteger;
      break;
    case TypeModifier::Float:
      ScalarType = ScalarTypeKind::Float;
      break;
    case TypeModifier::BFloat:
      ScalarType = ScalarTypeKind::BFloat;
      break;
    case TypeModifier::LMUL1:
      LMUL = LMULType(0);
      // Update ElementBitwidth need to update Scale too.
      Scale = LMUL.getScale(ElementBitwidth);
      break;
    default:
      llvm_unreachable("Unknown type modifier mask!");
    }
  }
}

void RVVType::applyLog2EEW(unsigned Log2EEW) {
  // update new elmul = (eew/sew) * lmul
  LMUL.MulLog2LMUL(Log2EEW - Log2_32(ElementBitwidth));
  // update new eew
  ElementBitwidth = 1 << Log2EEW;
  ScalarType = ScalarTypeKind::SignedInteger;
  Scale = LMUL.getScale(ElementBitwidth);
}

void RVVType::applyFixedSEW(unsigned NewSEW) {
  // Set invalid type if src and dst SEW are same.
  if (ElementBitwidth == NewSEW) {
    ScalarType = ScalarTypeKind::Invalid;
    return;
  }
  // Update new SEW
  ElementBitwidth = NewSEW;
  Scale = LMUL.getScale(ElementBitwidth);
}

void RVVType::applyFixedLog2LMUL(int Log2LMUL, enum FixedLMULType Type) {
  switch (Type) {
  case FixedLMULType::LargerThan:
    if (Log2LMUL <= LMUL.Log2LMUL) {
      ScalarType = ScalarTypeKind::Invalid;
      return;
    }
    break;
  case FixedLMULType::SmallerThan:
    if (Log2LMUL >= LMUL.Log2LMUL) {
      ScalarType = ScalarTypeKind::Invalid;
      return;
    }
    break;
  case FixedLMULType::SmallerOrEqual:
    if (Log2LMUL > LMUL.Log2LMUL) {
      ScalarType = ScalarTypeKind::Invalid;
      return;
    }
    break;
  }

  // Update new LMUL
  LMUL = LMULType(Log2LMUL);
  Scale = LMUL.getScale(ElementBitwidth);
}

std::optional<RVVTypes>
RVVTypeCache::computeTypes(BasicType BT, int Log2LMUL, unsigned NF,
                           ArrayRef<PrototypeDescriptor> Prototype) {
  RVVTypes Types;
  for (const PrototypeDescriptor &Proto : Prototype) {
    auto T = computeType(BT, Log2LMUL, Proto);
    if (!T)
      return std::nullopt;
    // Record legal type index
    Types.push_back(*T);
  }
  return Types;
}

// Compute the hash value of RVVType, used for cache the result of computeType.
static uint64_t computeRVVTypeHashValue(BasicType BT, int Log2LMUL,
                                        PrototypeDescriptor Proto) {
  // Layout of hash value:
  // 0               8    16          24        32          40
  // | Log2LMUL + 3  | BT  | Proto.PT | Proto.TM | Proto.VTM |
  assert(Log2LMUL >= -3 && Log2LMUL <= 3);
  return (Log2LMUL + 3) | (static_cast<uint64_t>(BT) & 0xff) << 8 |
         ((uint64_t)(Proto.PT & 0xff) << 16) |
         ((uint64_t)(Proto.TM & 0xff) << 24) |
         ((uint64_t)(Proto.VTM & 0xff) << 32);
}

std::optional<RVVTypePtr> RVVTypeCache::computeType(BasicType BT, int Log2LMUL,
                                                    PrototypeDescriptor Proto) {
  uint64_t Idx = computeRVVTypeHashValue(BT, Log2LMUL, Proto);
  // Search first
  auto It = LegalTypes.find(Idx);
  if (It != LegalTypes.end())
    return &(It->second);

  if (IllegalTypes.count(Idx))
    return std::nullopt;

  // Compute type and record the result.
  RVVType T(BT, Log2LMUL, Proto);
  if (T.isValid()) {
    // Record legal type index and value.
    std::pair<std::unordered_map<uint64_t, RVVType>::iterator, bool>
        InsertResult = LegalTypes.insert({Idx, T});
    return &(InsertResult.first->second);
  }
  // Record illegal type index.
  IllegalTypes.insert(Idx);
  return std::nullopt;
}

//===----------------------------------------------------------------------===//
// RVVIntrinsic implementation
//===----------------------------------------------------------------------===//
RVVIntrinsic::RVVIntrinsic(
    StringRef NewName, StringRef Suffix, StringRef NewOverloadedName,
    StringRef OverloadedSuffix, StringRef IRName, bool IsMasked,
    bool HasMaskedOffOperand, bool HasVL, PolicyScheme Scheme,
    bool SupportOverloading, bool HasBuiltinAlias, StringRef ManualCodegen,
    const RVVTypes &OutInTypes, const std::vector<int64_t> &NewIntrinsicTypes,
    const std::vector<StringRef> &RequiredFeatures, unsigned NF,
    Policy NewPolicyAttrs, bool HasFRMRoundModeOp)
    : IRName(IRName), IsMasked(IsMasked),
      HasMaskedOffOperand(HasMaskedOffOperand), HasVL(HasVL), Scheme(Scheme),
      SupportOverloading(SupportOverloading), HasBuiltinAlias(HasBuiltinAlias),
      ManualCodegen(ManualCodegen.str()), NF(NF), PolicyAttrs(NewPolicyAttrs) {

  // Init BuiltinName, Name and OverloadedName
  BuiltinName = NewName.str();
  Name = BuiltinName;
  if (NewOverloadedName.empty())
    OverloadedName = NewName.split("_").first.str();
  else
    OverloadedName = NewOverloadedName.str();
  if (!Suffix.empty())
    Name += "_" + Suffix.str();
  if (!OverloadedSuffix.empty())
    OverloadedName += "_" + OverloadedSuffix.str();

  updateNamesAndPolicy(IsMasked, hasPolicy(), Name, BuiltinName, OverloadedName,
                       PolicyAttrs, HasFRMRoundModeOp);

  // Init OutputType and InputTypes
  OutputType = OutInTypes[0];
  InputTypes.assign(OutInTypes.begin() + 1, OutInTypes.end());

  // IntrinsicTypes is unmasked TA version index. Need to update it
  // if there is merge operand (It is always in first operand).
  IntrinsicTypes = NewIntrinsicTypes;
  if ((IsMasked && hasMaskedOffOperand()) ||
      (!IsMasked && hasPassthruOperand())) {
    for (auto &I : IntrinsicTypes) {
      if (I >= 0)
        I += NF;
    }
  }
}

std::string RVVIntrinsic::getBuiltinTypeStr() const {
  std::string S;
  S += OutputType->getBuiltinStr();
  for (const auto &T : InputTypes) {
    S += T->getBuiltinStr();
  }
  return S;
}

std::string RVVIntrinsic::getSuffixStr(
    RVVTypeCache &TypeCache, BasicType Type, int Log2LMUL,
    llvm::ArrayRef<PrototypeDescriptor> PrototypeDescriptors) {
  SmallVector<std::string> SuffixStrs;
  for (auto PD : PrototypeDescriptors) {
    auto T = TypeCache.computeType(Type, Log2LMUL, PD);
    SuffixStrs.push_back((*T)->getShortStr());
  }
  return join(SuffixStrs, "_");
}

llvm::SmallVector<PrototypeDescriptor> RVVIntrinsic::computeBuiltinTypes(
    llvm::ArrayRef<PrototypeDescriptor> Prototype, bool IsMasked,
    bool HasMaskedOffOperand, bool HasVL, unsigned NF,
    PolicyScheme DefaultScheme, Policy PolicyAttrs, bool IsTuple) {
  SmallVector<PrototypeDescriptor> NewPrototype(Prototype.begin(),
                                                Prototype.end());
  bool HasPassthruOp = DefaultScheme == PolicyScheme::HasPassthruOperand;
  if (IsMasked) {
    // If HasMaskedOffOperand, insert result type as first input operand if
    // need.
    if (HasMaskedOffOperand && !PolicyAttrs.isTAMAPolicy()) {
      if (NF == 1) {
        NewPrototype.insert(NewPrototype.begin() + 1, NewPrototype[0]);
      } else if (NF > 1) {
        if (IsTuple) {
          PrototypeDescriptor BasePtrOperand = Prototype[1];
          PrototypeDescriptor MaskoffType = PrototypeDescriptor(
              static_cast<uint8_t>(BaseTypeModifier::Vector),
              static_cast<uint8_t>(getTupleVTM(NF)),
              BasePtrOperand.TM & ~static_cast<uint8_t>(TypeModifier::Pointer));
          NewPrototype.insert(NewPrototype.begin() + 1, MaskoffType);
        } else {
          // Convert
          // (void, op0 address, op1 address, ...)
          // to
          // (void, op0 address, op1 address, ..., maskedoff0, maskedoff1, ...)
          PrototypeDescriptor MaskoffType = NewPrototype[1];
          MaskoffType.TM &= ~static_cast<uint8_t>(TypeModifier::Pointer);
          NewPrototype.insert(NewPrototype.begin() + NF + 1, NF, MaskoffType);
        }
      }
    }
    if (HasMaskedOffOperand && NF > 1) {
      // Convert
      // (void, op0 address, op1 address, ..., maskedoff0, maskedoff1, ...)
      // to
      // (void, op0 address, op1 address, ..., mask, maskedoff0, maskedoff1,
      // ...)
      if (IsTuple)
        NewPrototype.insert(NewPrototype.begin() + 1,
                            PrototypeDescriptor::Mask);
      else
        NewPrototype.insert(NewPrototype.begin() + NF + 1,
                            PrototypeDescriptor::Mask);
    } else {
      // If IsMasked, insert PrototypeDescriptor:Mask as first input operand.
      NewPrototype.insert(NewPrototype.begin() + 1, PrototypeDescriptor::Mask);
    }
  } else {
    if (NF == 1) {
      if (PolicyAttrs.isTUPolicy() && HasPassthruOp)
        NewPrototype.insert(NewPrototype.begin(), NewPrototype[0]);
    } else if (PolicyAttrs.isTUPolicy() && HasPassthruOp) {
      if (IsTuple) {
        PrototypeDescriptor BasePtrOperand = Prototype[0];
        PrototypeDescriptor MaskoffType = PrototypeDescriptor(
            static_cast<uint8_t>(BaseTypeModifier::Vector),
            static_cast<uint8_t>(getTupleVTM(NF)),
            BasePtrOperand.TM & ~static_cast<uint8_t>(TypeModifier::Pointer));
        NewPrototype.insert(NewPrototype.begin(), MaskoffType);
      } else {
        // NF > 1 cases for segment load operations.
        // Convert
        // (void, op0 address, op1 address, ...)
        // to
        // (void, op0 address, op1 address, maskedoff0, maskedoff1, ...)
        PrototypeDescriptor MaskoffType = Prototype[1];
        MaskoffType.TM &= ~static_cast<uint8_t>(TypeModifier::Pointer);
        NewPrototype.insert(NewPrototype.begin() + NF + 1, NF, MaskoffType);
      }
    }
 }

  // If HasVL, append PrototypeDescriptor:VL to last operand
  if (HasVL)
    NewPrototype.push_back(PrototypeDescriptor::VL);

  return NewPrototype;
}

llvm::SmallVector<Policy> RVVIntrinsic::getSupportedUnMaskedPolicies() {
  return {Policy(Policy::PolicyType::Undisturbed)}; // TU
}

llvm::SmallVector<Policy>
RVVIntrinsic::getSupportedMaskedPolicies(bool HasTailPolicy,
                                         bool HasMaskPolicy) {
  if (HasTailPolicy && HasMaskPolicy)
    return {Policy(Policy::PolicyType::Undisturbed,
                   Policy::PolicyType::Agnostic), // TUM
            Policy(Policy::PolicyType::Undisturbed,
                   Policy::PolicyType::Undisturbed), // TUMU
            Policy(Policy::PolicyType::Agnostic,
                   Policy::PolicyType::Undisturbed)}; // MU
  if (HasTailPolicy && !HasMaskPolicy)
    return {Policy(Policy::PolicyType::Undisturbed,
                   Policy::PolicyType::Agnostic)}; // TU
  if (!HasTailPolicy && HasMaskPolicy)
    return {Policy(Policy::PolicyType::Agnostic,
                   Policy::PolicyType::Undisturbed)}; // MU
  llvm_unreachable("An RVV instruction should not be without both tail policy "
                   "and mask policy");
}

void RVVIntrinsic::updateNamesAndPolicy(
    bool IsMasked, bool HasPolicy, std::string &Name, std::string &BuiltinName,
    std::string &OverloadedName, Policy &PolicyAttrs, bool HasFRMRoundModeOp) {

  auto appendPolicySuffix = [&](const std::string &suffix) {
    Name += suffix;
    BuiltinName += suffix;
    OverloadedName += suffix;
  };

  // This follows the naming guideline under riscv-c-api-doc to add the
  // `__riscv_` suffix for all RVV intrinsics.
  Name = "__riscv_" + Name;
  OverloadedName = "__riscv_" + OverloadedName;

  if (HasFRMRoundModeOp) {
    Name += "_rm";
    BuiltinName += "_rm";
  }

  if (IsMasked) {
    if (PolicyAttrs.isTUMUPolicy())
      appendPolicySuffix("_tumu");
    else if (PolicyAttrs.isTUMAPolicy())
      appendPolicySuffix("_tum");
    else if (PolicyAttrs.isTAMUPolicy())
      appendPolicySuffix("_mu");
    else if (PolicyAttrs.isTAMAPolicy()) {
      Name += "_m";
      BuiltinName += "_m";
    } else
      llvm_unreachable("Unhandled policy condition");
  } else {
    if (PolicyAttrs.isTUPolicy())
      appendPolicySuffix("_tu");
    else if (PolicyAttrs.isTAPolicy()) // no suffix needed
      return;
    else
      llvm_unreachable("Unhandled policy condition");
  }
}

SmallVector<PrototypeDescriptor> parsePrototypes(StringRef Prototypes) {
  SmallVector<PrototypeDescriptor> PrototypeDescriptors;
  const StringRef Primaries("evwqom0ztulf");
  while (!Prototypes.empty()) {
    size_t Idx = 0;
    // Skip over complex prototype because it could contain primitive type
    // character.
    if (Prototypes[0] == '(')
      Idx = Prototypes.find_first_of(')');
    Idx = Prototypes.find_first_of(Primaries, Idx);
    assert(Idx != StringRef::npos);
    auto PD = PrototypeDescriptor::parsePrototypeDescriptor(
        Prototypes.slice(0, Idx + 1));
    if (!PD)
      llvm_unreachable("Error during parsing prototype.");
    PrototypeDescriptors.push_back(*PD);
    Prototypes = Prototypes.drop_front(Idx + 1);
  }
  return PrototypeDescriptors;
}

raw_ostream &operator<<(raw_ostream &OS, const RVVIntrinsicRecord &Record) {
  OS << "{";
  OS << "\"" << Record.Name << "\",";
  if (Record.OverloadedName == nullptr ||
      StringRef(Record.OverloadedName).empty())
    OS << "nullptr,";
  else
    OS << "\"" << Record.OverloadedName << "\",";
  OS << Record.PrototypeIndex << ",";
  OS << Record.SuffixIndex << ",";
  OS << Record.OverloadedSuffixIndex << ",";
  OS << (int)Record.PrototypeLength << ",";
  OS << (int)Record.SuffixLength << ",";
  OS << (int)Record.OverloadedSuffixSize << ",";
  OS << Record.RequiredExtensions << ",";
  OS << (int)Record.TypeRangeMask << ",";
  OS << (int)Record.Log2LMULMask << ",";
  OS << (int)Record.NF << ",";
  OS << (int)Record.HasMasked << ",";
  OS << (int)Record.HasVL << ",";
  OS << (int)Record.HasMaskedOffOperand << ",";
  OS << (int)Record.HasTailPolicy << ",";
  OS << (int)Record.HasMaskPolicy << ",";
  OS << (int)Record.HasFRMRoundModeOp << ",";
  OS << (int)Record.IsTuple << ",";
  OS << (int)Record.UnMaskedPolicyScheme << ",";
  OS << (int)Record.MaskedPolicyScheme << ",";
  OS << "},\n";
  return OS;
}

} // end namespace RISCV
} // end namespace clang