// Copyright 2023 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "riscv/riscv32g_encoding.h"

#include <cstdint>
#include <string>
#include <utility>

#include "absl/log/log.h"
#include "absl/strings/str_cat.h"
#include "mpact/sim/generic/immediate_operand.h"
#include "mpact/sim/generic/literal_operand.h"
#include "mpact/sim/generic/simple_resource.h"
#include "mpact/sim/generic/simple_resource_operand.h"
#include "riscv/riscv32g_bin_decoder.h"
#include "riscv/riscv32g_decoder.h"
#include "riscv/riscv32g_enums.h"
#include "riscv/riscv_register.h"
#include "riscv/riscv_state.h"

namespace mpact {
namespace sim {
namespace riscv {
namespace isa32 {

using generic::SimpleResourceOperand;

// Generic helper functions to create register operands.
template <typename RegType>
inline DestinationOperandInterface *GetRegisterDestinationOp(RiscVState *state,
                                                             std::string name,
                                                             int latency) {
  auto *reg = state->GetRegister<RegType>(name).first;
  return reg->CreateDestinationOperand(latency);
}

template <typename RegType>
inline DestinationOperandInterface *GetRegisterDestinationOp(
    RiscVState *state, std::string name, int latency, std::string op_name) {
  auto *reg = state->GetRegister<RegType>(name).first;
  return reg->CreateDestinationOperand(latency, op_name);
}

template <typename T>
inline DestinationOperandInterface *GetCSRSetBitsDestinationOp(
    RiscVState *state, std::string name, int latency, std::string op_name) {
  auto result = state->csr_set()->GetCsr(name);
  if (!result.ok()) {
    LOG(ERROR) << "No such CSR '" << name << "'";
    return nullptr;
  }
  auto *csr = result.value();
  auto *op = csr->CreateSetDestinationOperand(latency, op_name);
  return op;
}

template <typename RegType>
inline SourceOperandInterface *GetRegisterSourceOp(RiscVState *state,
                                                   std::string name) {
  auto *reg = state->GetRegister<RegType>(name).first;
  auto *op = reg->CreateSourceOperand();
  return op;
}

template <typename RegType>
inline SourceOperandInterface *GetRegisterSourceOp(RiscVState *state,
                                                   std::string name,
                                                   std::string op_name) {
  auto *reg = state->GetRegister<RegType>(name).first;
  auto *op = reg->CreateSourceOperand(op_name);
  return op;
}

RiscV32GEncoding::RiscV32GEncoding(RiscVState *state) : state_(state) {
  InitializeSourceOperandGetters();
  InitializeDestinationOperandGetters();
  InitializeSimpleResourceGetters();
  resource_pool_ = new generic::SimpleResourcePool("RiscV32G", 128);
  resource_delay_line_ =
      state_->CreateAndAddDelayLine<generic::SimpleResourceDelayLine>(8);
}

RiscV32GEncoding::~RiscV32GEncoding() { delete resource_pool_; }

void RiscV32GEncoding::InitializeSourceOperandGetters() {
  // Source operand getters.
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kAAq),
                     [this]() -> SourceOperandInterface * {
                       if (encoding::inst32_format::ExtractAq(inst_word_)) {
                         return new generic::IntLiteralOperand<1>();
                       }
                       return new generic::IntLiteralOperand<0>();
                     }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kARl),
                     [this]() -> SourceOperandInterface * {
                       if (encoding::inst32_format::ExtractRl(inst_word_)) {
                         return new generic::IntLiteralOperand<1>();
                       }
                       return new generic::IntLiteralOperand<0>();
                     }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kBImm12), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst32_format::ExtractBImm(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kC3drs2), [this]() {
        auto num = encoding::inst16_format::ExtractCsRs2(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kC3frs2), [this]() {
        auto num = encoding::inst16_format::ExtractCsRs2(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kC3rs1), [this]() {
        auto num = encoding::inst16_format::ExtractCsRs1(inst_word_);
        return GetRegisterSourceOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, num),
            xreg_alias_[num]);
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kC3rs2), [this]() {
        auto num = encoding::inst16_format::ExtractCsRs2(inst_word_);
        return GetRegisterSourceOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, num),
            xreg_alias_[num]);
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kCSRUimm5), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst32_format::ExtractIUimm5(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kCdrs2), [this]() {
        auto num = encoding::c_r::ExtractRs2(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kCfrs2), [this]() {
        auto num = encoding::c_r::ExtractRs2(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kCrs1), [this]() {
        auto num = encoding::c_r::ExtractRs1(inst_word_);
        return GetRegisterSourceOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, num),
            xreg_alias_[num]);
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kCrs2), [this]() {
        auto num = encoding::c_r::ExtractRs2(inst_word_);
        return GetRegisterSourceOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, num),
            xreg_alias_[num]);
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kCsr), [this]() {
        auto csr_indx = encoding::i_type::ExtractUImm12(inst_word_);
        auto res = state_->csr_set()->GetCsr(csr_indx);
        if (!res.ok()) {
          return new generic::ImmediateOperand<uint32_t>(csr_indx);
        }
        auto *csr = res.value();
        return new generic::ImmediateOperand<uint32_t>(csr_indx, csr->name());
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kDrs1), [this]() {
        int num = encoding::r_type::ExtractRs1(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kDrs2), [this]() {
        int num = encoding::r_type::ExtractRs2(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kDrs3), [this]() {
        int num = encoding::r4_type::ExtractRs3(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kFrs1), [this]() {
        int num = encoding::r_type::ExtractRs1(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kFrs2), [this]() {
        int num = encoding::r_type::ExtractRs2(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kFrs3), [this]() {
        int num = encoding::r4_type::ExtractRs3(inst_word_);
        return GetRegisterSourceOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICbImm8), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst16_format::ExtractBimm(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICiImm6), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::c_i::ExtractImm6(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICiImm612), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst16_format::ExtractImm18(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICiImm6x16), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst16_format::ExtractCiImm10(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICiUimm6), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst16_format::ExtractUimm6(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICiUimm6x4), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst16_format::ExtractCiImmW(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICiUimm6x8), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst16_format::ExtractCiImmD(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICiwUimm8x4), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst16_format::ExtractCiwImm10(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICjImm11), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst16_format::ExtractJimm(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kIClUimm5x4), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst16_format::ExtractClImmW(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kIClUimm5x8), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst16_format::ExtractClImmD(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICssUimm6x4), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst16_format::ExtractCssImmW(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kICssUimm6x8), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst16_format::ExtractCssImmD(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kIImm12), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst32_format::ExtractImm12(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kIUimm5), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst32_format::ExtractRUimm5(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kJImm12), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst32_format::ExtractImm12(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kJImm20), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst32_format::ExtractJImm(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kPred), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst32_format::ExtractPred(inst_word_));
      }));
  source_op_getters_.insert(std::make_pair(
      static_cast<int>(SourceOpEnum::kRd),
      [this]() -> SourceOperandInterface * {
        int num = encoding::r_type::ExtractRd(inst_word_);
        if (num == 0)
          return new generic::IntLiteralOperand<0>({1}, xreg_alias_[0]);
        return GetRegisterSourceOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, num),
            xreg_alias_[num]);
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kRm),
                     [this]() -> SourceOperandInterface * {
                       uint32_t rm = (inst_word_ >> 12) & 0x7;
                       switch (rm) {
                         case 0:
                           return new generic::IntLiteralOperand<0>();
                         case 1:
                           return new generic::IntLiteralOperand<1>();
                         case 2:
                           return new generic::IntLiteralOperand<2>();
                         case 3:
                           return new generic::IntLiteralOperand<3>();
                         case 4:
                           return new generic::IntLiteralOperand<4>();
                         case 5:
                           return new generic::IntLiteralOperand<5>();
                         case 6:
                           return new generic::IntLiteralOperand<6>();
                         case 7:
                           return new generic::IntLiteralOperand<7>();
                         default:
                           return nullptr;
                       }
                     }));
  source_op_getters_.insert(std::make_pair(
      static_cast<int>(SourceOpEnum::kRs1),
      [this]() -> SourceOperandInterface * {
        int num = encoding::r_type::ExtractRs1(inst_word_);
        if (num == 0)
          return new generic::IntLiteralOperand<0>({1}, xreg_alias_[0]);
        return GetRegisterSourceOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, num),
            xreg_alias_[num]);
      }));
  source_op_getters_.insert(std::make_pair(
      static_cast<int>(SourceOpEnum::kRs2),
      [this]() -> SourceOperandInterface * {
        int num = encoding::r_type::ExtractRs2(inst_word_);
        if (num == 0)
          return new generic::IntLiteralOperand<0>({1}, xreg_alias_[0]);
        return GetRegisterSourceOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, num),
            xreg_alias_[num]);
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kSImm12), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst32_format::ExtractSImm(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kSucc), [this]() {
        return new generic::ImmediateOperand<uint32_t>(
            encoding::inst32_format::ExtractSucc(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kUImm20), [this]() {
        return new generic::ImmediateOperand<int32_t>(
            encoding::inst32_format::ExtractUImm(inst_word_));
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kX0), [this]() {
        return new generic::IntLiteralOperand<0>({1}, xreg_alias_[0]);
      }));
  source_op_getters_.insert(
      std::make_pair(static_cast<int>(SourceOpEnum::kX2), [this]() {
        return GetRegisterSourceOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, 2), xreg_alias_[2]);
      }));
  source_op_getters_.insert(std::make_pair(
      static_cast<int>(SourceOpEnum::kNone), []() { return nullptr; }));
}

void RiscV32GEncoding::InitializeDestinationOperandGetters() {
  // Destination operand getters.
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kC3drd), [this](int latency) {
        int num = encoding::inst16_format::ExtractClRd(inst_word_);
        return GetRegisterDestinationOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num), latency);
      }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kC3frd), [this](int latency) {
        int num = encoding::inst16_format::ExtractClRd(inst_word_);
        return GetRegisterDestinationOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num), latency);
      }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kC3rd), [this](int latency) {
        int num = encoding::inst16_format::ExtractClRd(inst_word_);
        return GetRegisterDestinationOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, num), latency);
      }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kC3rs1), [this](int latency) {
        int num = encoding::inst16_format::ExtractClRs1(inst_word_);
        return GetRegisterDestinationOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, num), latency,
            xreg_alias_[num]);
      }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kCsr), [this](int latency) {
        return GetRegisterDestinationOp<RV32Register>(
            state_, RiscVState::kCsrName, latency);
      }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kDrd), [this](int latency) {
        int num = encoding::r_type::ExtractRd(inst_word_);
        return GetRegisterDestinationOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num), latency);
      }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kFrd), [this](int latency) {
        int num = encoding::r_type::ExtractRd(inst_word_);
        return GetRegisterDestinationOp<RVFpRegister>(
            state_, absl::StrCat(RiscVState::kFregPrefix, num), latency);
      }));
  dest_op_getters_.insert(std::make_pair(
      static_cast<int>(DestOpEnum::kNextPc), [this](int latency) {
        return GetRegisterDestinationOp<RV32Register>(
            state_, RiscVState::kPcName, latency);
      }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kRd),
                     [this](int latency) -> DestinationOperandInterface * {
                       int num = encoding::r_type::ExtractRd(inst_word_);
                       if (num == 0) {
                         return GetRegisterDestinationOp<RV32Register>(
                             state_, "X0Dest", 0, xreg_alias_[0]);
                       } else {
                         return GetRegisterDestinationOp<RV32Register>(
                             state_, absl::StrCat(RiscVState::kXregPrefix, num),
                             latency, xreg_alias_[num]);
                       }
                     }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kX0), [this](int) {
        return GetRegisterDestinationOp<RV32Register>(state_, "X0Dest", 0,
                                                      xreg_alias_[0]);
      }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kX1), [this](int latency) {
        return GetRegisterDestinationOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, 1), latency,
            xreg_alias_[1]);
      }));
  dest_op_getters_.insert(
      std::make_pair(static_cast<int>(DestOpEnum::kX2), [this](int latency) {
        return GetRegisterDestinationOp<RV32Register>(
            state_, absl::StrCat(RiscVState::kXregPrefix, 2), latency,
            xreg_alias_[2]);
      }));
  dest_op_getters_.insert(std::make_pair(
      static_cast<int>(DestOpEnum::kFflags), [this](int latency) {
        return GetCSRSetBitsDestinationOp<uint32_t>(state_, "fflags", latency,
                                                    "");
      }));
  dest_op_getters_.insert(std::make_pair(static_cast<int>(DestOpEnum::kNone),
                                         [](int latency) { return nullptr; }));
}

// Parse the instruction word to determine the opcode.
void RiscV32GEncoding::ParseInstruction(uint32_t inst_word) {
  inst_word_ = inst_word;
  if ((inst_word_ & 0x3) == 3) {
    opcode_ = mpact::sim::riscv::encoding::DecodeRiscVGInst32(inst_word_);
    return;
  }

  opcode_ = mpact::sim::riscv::encoding::DecodeRiscVCInst16(
      static_cast<uint16_t>(inst_word_ & 0xffff));
}

void RiscV32GEncoding::InitializeComplexResourceOperandGetters() {
  complex_resource_getters_.insert(
      std::make_pair(static_cast<int>(ComplexResourceEnum::kNone),
                     [](int begin, int end) { return nullptr; }));
}

ResourceOperandInterface *RiscV32GEncoding::GetComplexResourceOperand(
    SlotEnum, int, OpcodeEnum, ComplexResourceEnum resource, int begin,
    int end) {
  int index = static_cast<int>(resource);
  auto iter = complex_resource_getters_.find(index);
  if (iter == complex_resource_getters_.end()) {
    LOG(WARNING) << "No complex resource getter found for resource: " << index;
    return nullptr;
  }
  return (iter->second)(begin, end);
}

void RiscV32GEncoding::InitializeSimpleResourceGetters() {
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kNone), []() { return nullptr; }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kC3drd),
      [this]() -> generic::SimpleResource * {
        int num = encoding::inst16_format::ExtractClRd(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kC3drs2),
      [this]() -> generic::SimpleResource * {
        int num = encoding::inst16_format::ExtractCsRs2(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kC3frd),
      [this]() -> generic::SimpleResource * {
        int num = encoding::inst16_format::ExtractClRd(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kC3frs2),
      [this]() -> generic::SimpleResource * {
        int num = encoding::inst16_format::ExtractCsRs2(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kC3rd),
      [this]() -> generic::SimpleResource * {
        int num = encoding::inst16_format::ExtractClRd(inst_word_);
        // If num is 0 it refers to the zero register. No resource.
        if (num == 0) return nullptr;
        return resource_pool_->GetOrAddResource(absl::StrCat("x", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kC3rs1),
      [this]() -> generic::SimpleResource * {
        int num = encoding::inst16_format::ExtractClRs1(inst_word_);
        // If num is 0 it refers to the zero register. No resource.
        if (num == 0) return nullptr;
        return resource_pool_->GetOrAddResource(absl::StrCat("x", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kC3rs2),
      [this]() -> generic::SimpleResource * {
        int num = encoding::inst16_format::ExtractCsRs2(inst_word_);
        // If num is 0 it refers to the zero register. No resource.
        if (num == 0) return nullptr;
        return resource_pool_->GetOrAddResource(absl::StrCat("x", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kCdrs2),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::c_r::ExtractRs2(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kCfrs2),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::c_r::ExtractRs2(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kCrs1),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::c_r::ExtractRs1(inst_word_);
        // If num is 0 it refers to the zero register. No resource.
        if (num == 0) return nullptr;
        return resource_pool_->GetOrAddResource(absl::StrCat("x", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kCrs2),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::c_r::ExtractRs2(inst_word_);
        // If num is 0 it refers to the zero register. No resource.
        if (num == 0) return nullptr;
        return resource_pool_->GetOrAddResource(absl::StrCat("x", num));
      }));
  simple_resource_getters_.insert(
      std::make_pair(static_cast<int>(SimpleResourceEnum::kCsr),
                     [this]() -> generic::SimpleResource * {
                       return resource_pool_->GetOrAddResource("csr");
                     }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kDrd),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::r4_type::ExtractRd(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kDrs1),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::a_type::ExtractRs1(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kDrs2),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::a_type::ExtractRs2(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kDrs3),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::r4_type::ExtractRs3(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kFrd),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::r4_type::ExtractRd(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kFrs1),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::r4_type::ExtractRs1(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kFrs2),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::r4_type::ExtractRs2(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kFrs3),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::r4_type::ExtractRs3(inst_word_);
        return resource_pool_->GetOrAddResource(absl::StrCat("d", num));
      }));
  simple_resource_getters_.insert(
      std::make_pair(static_cast<int>(SimpleResourceEnum::kNextPc),
                     [this]() -> generic::SimpleResource * {
                       return resource_pool_->GetOrAddResource("next_pc");
                     }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kRd),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::a_type::ExtractRd(inst_word_);
        // If num is 0 it refers to the zero register. No resource.
        if (num == 0) return nullptr;
        return resource_pool_->GetOrAddResource(absl::StrCat("x", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kRs1),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::a_type::ExtractRs1(inst_word_);
        // If num is 0 it refers to the zero register. No resource.
        if (num == 0) return nullptr;
        return resource_pool_->GetOrAddResource(absl::StrCat("x", num));
      }));
  simple_resource_getters_.insert(std::make_pair(
      static_cast<int>(SimpleResourceEnum::kRs2),
      [this]() -> generic::SimpleResource * {
        auto num = encoding::a_type::ExtractRs2(inst_word_);
        // If num is 0 it refers to the zero register. No resource.
        if (num == 0) return nullptr;
        return resource_pool_->GetOrAddResource(absl::StrCat("x", num));
      }));
  // X0 is constant 0, so no resource issue.
  simple_resource_getters_.insert(
      std::make_pair(static_cast<int>(SimpleResourceEnum::kX0),
                     []() -> generic::SimpleResource * { return nullptr; }));
  simple_resource_getters_.insert(
      std::make_pair(static_cast<int>(SimpleResourceEnum::kX1),
                     [this]() -> generic::SimpleResource * {
                       return resource_pool_->GetOrAddResource("x1");
                     }));
  simple_resource_getters_.insert(
      std::make_pair(static_cast<int>(SimpleResourceEnum::kX2),
                     [this]() -> generic::SimpleResource * {
                       return resource_pool_->GetOrAddResource("x2");
                     }));
}

ResourceOperandInterface *RiscV32GEncoding::GetSimpleResourceOperand(
    SlotEnum, int, OpcodeEnum, SimpleResourceVector &resource_vec, int end) {
  if (resource_vec.empty()) return nullptr;
  auto *resource_set = resource_pool_->CreateResourceSet();
  for (auto resource_enum : resource_vec) {
    int index = static_cast<int>(resource_enum);
    auto iter = simple_resource_getters_.find(index);
    if (iter == simple_resource_getters_.end()) {
      LOG(WARNING) << "No getter for simple resource " << index;
      continue;
    }
    auto *resource = (iter->second)();
    auto status = resource_set->AddResource(resource);
    if (!status.ok()) {
      LOG(ERROR) << "Unable to add resource to resource set ("
                 << static_cast<int>(resource_enum) << ")";
    }
  }
  auto *op = new SimpleResourceOperand(resource_set, end, resource_delay_line_);
  return op;
}

DestinationOperandInterface *RiscV32GEncoding::GetDestination(
    SlotEnum, int, OpcodeEnum opcode, DestOpEnum dest_op, int dest_no,
    int latency) {
  int index = static_cast<int>(dest_op);
  auto iter = dest_op_getters_.find(index);
  if (iter == dest_op_getters_.end()) {
    LOG(ERROR) << absl::StrCat("No getter for destination op enum value ",
                               index, "for instruction ",
                               kOpcodeNames[static_cast<int>(opcode)]);
    return nullptr;
  }
  return (iter->second)(latency);
}

SourceOperandInterface *RiscV32GEncoding::GetSource(SlotEnum, int,
                                                    OpcodeEnum opcode,
                                                    SourceOpEnum source_op,
                                                    int source_no) {
  int index = static_cast<int>(source_op);
  auto iter = source_op_getters_.find(index);
  if (iter == source_op_getters_.end()) {
    LOG(ERROR) << absl::StrCat("No getter for source op enum value ", index,
                               " for instruction ",
                               kOpcodeNames[static_cast<int>(opcode)]);
    return nullptr;
  }
  return (iter->second)();
}

}  // namespace isa32
}  // namespace riscv
}  // namespace sim
}  // namespace mpact