//===- DXILEmitter.cpp - DXIL operation Emitter ---------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// DXILEmitter uses the descriptions of DXIL operation to construct enum and
// helper functions for DXIL operation.
//
//===----------------------------------------------------------------------===//

#include "Basic/SequenceToOffsetTable.h"
#include "Common/CodeGenTarget.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/CodeGenTypes/MachineValueType.h"
#include "llvm/Support/DXILABI.h"
#include "llvm/Support/VersionTuple.h"
#include "llvm/TableGen/Error.h"
#include "llvm/TableGen/Record.h"
#include "llvm/TableGen/TableGenBackend.h"

#include <string>
#include <vector>

using namespace llvm;
using namespace llvm::dxil;

namespace {

struct DXILOperationDesc {
  std::string OpName; // name of DXIL operation
  int OpCode;         // ID of DXIL operation
  StringRef OpClass;  // name of the opcode class
  StringRef Doc;      // the documentation description of this instruction
  // Vector of operand type records - return type is at index 0
  SmallVector<Record *> OpTypes;
  SmallVector<Record *> OverloadRecs;
  SmallVector<Record *> StageRecs;
  SmallVector<Record *> AttrRecs;
  StringRef Intrinsic; // The llvm intrinsic map to OpName. Default is "" which
                       // means no map exists
  SmallVector<StringRef, 4>
      ShaderStages; // shader stages to which this applies, empty for all.
  int OverloadParamIndex;             // Index of parameter with overload type.
                                      //   -1 : no overload types
  SmallVector<StringRef, 4> counters; // counters for this inst.
  DXILOperationDesc(const Record *);
};
} // end anonymous namespace

/// Return dxil::ParameterKind corresponding to input LLVMType record
///
/// \param R TableGen def record of class LLVMType
/// \return ParameterKind As defined in llvm/Support/DXILABI.h

static ParameterKind getParameterKind(const Record *R) {
  auto VTRec = R->getValueAsDef("VT");
  switch (getValueType(VTRec)) {
  case MVT::isVoid:
    return ParameterKind::Void;
  case MVT::f16:
    return ParameterKind::Half;
  case MVT::f32:
    return ParameterKind::Float;
  case MVT::f64:
    return ParameterKind::Double;
  case MVT::i1:
    return ParameterKind::I1;
  case MVT::i8:
    return ParameterKind::I8;
  case MVT::i16:
    return ParameterKind::I16;
  case MVT::i32:
    return ParameterKind::I32;
  case MVT::fAny:
  case MVT::iAny:
  case MVT::Any:
    return ParameterKind::Overload;
  default:
    llvm_unreachable(
        "Support for specified parameter type not yet implemented");
  }
}

/// In-place sort TableGen records of class with a field
///    Version dxil_version
/// in the ascending version order.
static void AscendingSortByVersion(std::vector<Record *> &Recs) {
  std::sort(Recs.begin(), Recs.end(), [](Record *RecA, Record *RecB) {
    unsigned RecAMaj =
        RecA->getValueAsDef("dxil_version")->getValueAsInt("Major");
    unsigned RecAMin =
        RecA->getValueAsDef("dxil_version")->getValueAsInt("Minor");
    unsigned RecBMaj =
        RecB->getValueAsDef("dxil_version")->getValueAsInt("Major");
    unsigned RecBMin =
        RecB->getValueAsDef("dxil_version")->getValueAsInt("Minor");

    return (VersionTuple(RecAMaj, RecAMin) < VersionTuple(RecBMaj, RecBMin));
  });
}

/// Construct an object using the DXIL Operation records specified
/// in DXIL.td. This serves as the single source of reference of
/// the information extracted from the specified Record R, for
/// C++ code generated by this TableGen backend.
//  \param R Object representing TableGen record of a DXIL Operation
DXILOperationDesc::DXILOperationDesc(const Record *R) {
  OpName = R->getNameInitAsString();
  OpCode = R->getValueAsInt("OpCode");

  Doc = R->getValueAsString("Doc");
  SmallVector<Record *> ParamTypeRecs;

  ParamTypeRecs.push_back(R->getValueAsDef("result"));

  std::vector<Record *> ArgTys = R->getValueAsListOfDefs("arguments");
  for (auto Ty : ArgTys) {
    ParamTypeRecs.push_back(Ty);
  }
  size_t ParamTypeRecsSize = ParamTypeRecs.size();
  // Populate OpTypes with return type and parameter types

  // Parameter indices of overloaded parameters.
  // This vector contains overload parameters in the order used to
  // resolve an LLVMMatchType in accordance with  convention outlined in
  // the comment before the definition of class LLVMMatchType in
  // llvm/IR/Intrinsics.td
  SmallVector<int> OverloadParamIndices;
  for (unsigned i = 0; i < ParamTypeRecsSize; i++) {
    auto TR = ParamTypeRecs[i];
    // Track operation parameter indices of any overload types
    auto isAny = TR->getValueAsInt("isAny");
    if (isAny == 1) {
      // All overload types in a DXIL Op are required to be of the same type.
      if (!OverloadParamIndices.empty()) {
        [[maybe_unused]] bool knownType = true;
        // Ensure that the same overload type registered earlier is being used
        for (auto Idx : OverloadParamIndices) {
          if (TR != ParamTypeRecs[Idx]) {
            knownType = false;
            break;
          }
        }
        assert(knownType && "Specification of multiple differing overload "
                            "parameter types not yet supported");
      } else {
        OverloadParamIndices.push_back(i);
      }
    }
    // Populate OpTypes array according to the type specification
    if (TR->isAnonymous()) {
      // Check prior overload types exist
      assert(!OverloadParamIndices.empty() &&
             "No prior overloaded parameter found to match.");
      // Get the parameter index of anonymous type, TR, references
      auto OLParamIndex = TR->getValueAsInt("Number");
      // Resolve and insert the type to that at OLParamIndex
      OpTypes.emplace_back(ParamTypeRecs[OLParamIndex]);
    } else {
      // A non-anonymous type. Just record it in OpTypes
      OpTypes.emplace_back(TR);
    }
  }

  // Set the index of the overload parameter, if any.
  OverloadParamIndex = -1; // default; indicating none
  if (!OverloadParamIndices.empty()) {
    assert(OverloadParamIndices.size() == 1 &&
           "Multiple overload type specification not supported");
    OverloadParamIndex = OverloadParamIndices[0];
  }

  // Get overload records
  std::vector<Record *> Recs = R->getValueAsListOfDefs("overloads");

  // Sort records in ascending order of DXIL version
  AscendingSortByVersion(Recs);

  for (Record *CR : Recs) {
    OverloadRecs.push_back(CR);
  }

  // Get stage records
  Recs = R->getValueAsListOfDefs("stages");

  if (Recs.empty()) {
    PrintFatalError(R, Twine("Atleast one specification of valid stage for ") +
                           OpName + " is required");
  }

  // Sort records in ascending order of DXIL version
  AscendingSortByVersion(Recs);

  for (Record *CR : Recs) {
    StageRecs.push_back(CR);
  }

  // Get attribute records
  Recs = R->getValueAsListOfDefs("attributes");

  // Sort records in ascending order of DXIL version
  AscendingSortByVersion(Recs);

  for (Record *CR : Recs) {
    AttrRecs.push_back(CR);
  }

  // Get the operation class
  OpClass = R->getValueAsDef("OpClass")->getName();

  if (!OpClass.str().compare("UnknownOpClass")) {
    PrintFatalError(R, Twine("Unspecified DXIL OpClass for DXIL operation - ") +
                           OpName);
  }

  const RecordVal *RV = R->getValue("LLVMIntrinsic");
  if (RV && RV->getValue()) {
    if (DefInit *DI = dyn_cast<DefInit>(RV->getValue())) {
      auto *IntrinsicDef = DI->getDef();
      auto DefName = IntrinsicDef->getName();
      assert(DefName.starts_with("int_") && "invalid intrinsic name");
      // Remove the int_ from intrinsic name.
      Intrinsic = DefName.substr(4);
    }
  }
}

/// Return a string representation of ParameterKind enum
/// \param Kind Parameter Kind enum value
/// \return std::string string representation of input Kind
static std::string getParameterKindStr(ParameterKind Kind) {
  switch (Kind) {
  case ParameterKind::Invalid:
    return "Invalid";
  case ParameterKind::Void:
    return "Void";
  case ParameterKind::Half:
    return "Half";
  case ParameterKind::Float:
    return "Float";
  case ParameterKind::Double:
    return "Double";
  case ParameterKind::I1:
    return "I1";
  case ParameterKind::I8:
    return "I8";
  case ParameterKind::I16:
    return "I16";
  case ParameterKind::I32:
    return "I32";
  case ParameterKind::I64:
    return "I64";
  case ParameterKind::Overload:
    return "Overload";
  case ParameterKind::CBufferRet:
    return "CBufferRet";
  case ParameterKind::ResourceRet:
    return "ResourceRet";
  case ParameterKind::DXILHandle:
    return "DXILHandle";
  }
  llvm_unreachable("Unknown llvm::dxil::ParameterKind enum");
}

/// Return a string representation of OverloadKind enum that maps to
/// input LLVMType record
/// \param R TableGen def record of class LLVMType
/// \return std::string string representation of OverloadKind

static std::string getOverloadKindStr(const Record *R) {
  Record *VTRec = R->getValueAsDef("VT");
  switch (getValueType(VTRec)) {
  case MVT::f16:
    return "OverloadKind::HALF";
  case MVT::f32:
    return "OverloadKind::FLOAT";
  case MVT::f64:
    return "OverloadKind::DOUBLE";
  case MVT::i1:
    return "OverloadKind::I1";
  case MVT::i8:
    return "OverloadKind::I8";
  case MVT::i16:
    return "OverloadKind::I16";
  case MVT::i32:
    return "OverloadKind::I32";
  case MVT::i64:
    return "OverloadKind::I64";
  default:
    llvm_unreachable("Support for specified fixed type option for overload "
                     "type not supported");
  }
}

/// Return a string representation of valid overload information denoted
// by input records
//
/// \param Recs A vector of records of TableGen Overload records
/// \return std::string string representation of overload mask string
///         predicated by DXIL Version. E.g.,
//          {{{1, 0}, Mask1}, {{1, 2}, Mask2}, ...}
static std::string getOverloadMaskString(const SmallVector<Record *> Recs) {
  std::string MaskString = "";
  std::string Prefix = "";
  MaskString.append("{");
  // If no overload information records were specified, assume the operation
  // a) to be supported in DXIL Version 1.0 and later
  // b) has no overload types
  if (Recs.empty()) {
    MaskString.append("{{1, 0}, OverloadKind::UNDEFINED}}");
  } else {
    for (auto Rec : Recs) {
      unsigned Major =
          Rec->getValueAsDef("dxil_version")->getValueAsInt("Major");
      unsigned Minor =
          Rec->getValueAsDef("dxil_version")->getValueAsInt("Minor");
      MaskString.append(Prefix)
          .append("{{")
          .append(std::to_string(Major))
          .append(", ")
          .append(std::to_string(Minor).append("}, "));

      std::string PipePrefix = "";
      auto Tys = Rec->getValueAsListOfDefs("overload_types");
      if (Tys.empty()) {
        MaskString.append("OverloadKind::UNDEFINED");
      }
      for (const auto *Ty : Tys) {
        MaskString.append(PipePrefix).append(getOverloadKindStr(Ty));
        PipePrefix = " | ";
      }

      MaskString.append("}");
      Prefix = ", ";
    }
    MaskString.append("}");
  }
  return MaskString;
}

/// Return a string representation of valid shader stag information denoted
// by input records
//
/// \param Recs A vector of records of TableGen Stages records
/// \return std::string string representation of stages mask string
///         predicated by DXIL Version. E.g.,
//          {{{1, 0}, Mask1}, {{1, 2}, Mask2}, ...}
static std::string getStageMaskString(const SmallVector<Record *> Recs) {
  std::string MaskString = "";
  std::string Prefix = "";
  MaskString.append("{");
  // Atleast one stage information record is expected to be specified.
  if (Recs.empty()) {
    PrintFatalError("Atleast one specification of valid stages for "
                    "operation must be specified");
  }

  for (auto Rec : Recs) {
    unsigned Major = Rec->getValueAsDef("dxil_version")->getValueAsInt("Major");
    unsigned Minor = Rec->getValueAsDef("dxil_version")->getValueAsInt("Minor");
    MaskString.append(Prefix)
        .append("{{")
        .append(std::to_string(Major))
        .append(", ")
        .append(std::to_string(Minor).append("}, "));

    std::string PipePrefix = "";
    auto Stages = Rec->getValueAsListOfDefs("shader_stages");
    if (Stages.empty()) {
      PrintFatalError("No valid stages for operation specified");
    }
    for (const auto *S : Stages) {
      MaskString.append(PipePrefix).append("ShaderKind::").append(S->getName());
      PipePrefix = " | ";
    }

    MaskString.append("}");
    Prefix = ", ";
  }
  MaskString.append("}");
  return MaskString;
}

/// Return a string representation of valid attribute information denoted
// by input records
//
/// \param Recs A vector of records of TableGen Attribute records
/// \return std::string string representation of stages mask string
///         predicated by DXIL Version. E.g.,
//          {{{1, 0}, Mask1}, {{1, 2}, Mask2}, ...}
static std::string getAttributeMaskString(const SmallVector<Record *> Recs) {
  std::string MaskString = "";
  std::string Prefix = "";
  MaskString.append("{");

  for (auto Rec : Recs) {
    unsigned Major = Rec->getValueAsDef("dxil_version")->getValueAsInt("Major");
    unsigned Minor = Rec->getValueAsDef("dxil_version")->getValueAsInt("Minor");
    MaskString.append(Prefix)
        .append("{{")
        .append(std::to_string(Major))
        .append(", ")
        .append(std::to_string(Minor).append("}, "));

    std::string PipePrefix = "";
    auto Attrs = Rec->getValueAsListOfDefs("op_attrs");
    if (Attrs.empty()) {
      MaskString.append("Attribute::None");
    } else {
      for (const auto *Attr : Attrs) {
        MaskString.append(PipePrefix)
            .append("Attribute::")
            .append(Attr->getName());
        PipePrefix = " | ";
      }
    }

    MaskString.append("}");
    Prefix = ", ";
  }
  MaskString.append("}");
  return MaskString;
}

/// Emit Enums of DXIL Ops
/// \param A vector of DXIL Ops
/// \param Output stream
static void emitDXILEnums(std::vector<DXILOperationDesc> &Ops,
                          raw_ostream &OS) {
  OS << "#ifdef DXIL_OP_ENUM\n\n";
  OS << "// Enumeration for operations specified by DXIL\n";
  OS << "enum class OpCode : unsigned {\n";

  for (auto &Op : Ops) {
    // Name = ID, // Doc
    OS << Op.OpName << " = " << Op.OpCode << ", // " << Op.Doc << "\n";
  }

  OS << "\n};\n\n";

  OS << "// Groups for DXIL operations with equivalent function templates\n";
  OS << "enum class OpCodeClass : unsigned {\n";
  // Build an OpClass set to print
  SmallSet<StringRef, 2> OpClassSet;
  for (auto &Op : Ops) {
    OpClassSet.insert(Op.OpClass);
  }
  for (auto &C : OpClassSet) {
    OS << C << ",\n";
  }
  OS << "\n};\n\n";
  OS << "#undef DXIL_OP_ENUM\n";
  OS << "#endif\n\n";
}

/// Emit map of DXIL operation to LLVM or DirectX intrinsic
/// \param A vector of DXIL Ops
/// \param Output stream
static void emitDXILIntrinsicMap(std::vector<DXILOperationDesc> &Ops,
                                 raw_ostream &OS) {
  OS << "#ifdef DXIL_OP_INTRINSIC\n";
  OS << "\n";
  for (const auto &Op : Ops) {
    if (Op.Intrinsic.empty())
      continue;
    OS << "DXIL_OP_INTRINSIC(dxil::OpCode::" << Op.OpName
       << ", Intrinsic::" << Op.Intrinsic << ")\n";
  }
  OS << "\n";
  OS << "#undef DXIL_OP_INTRINSIC\n";
  OS << "#endif\n\n";
}

/// Emit DXIL operation table
/// \param A vector of DXIL Ops
/// \param Output stream
static void emitDXILOperationTable(std::vector<DXILOperationDesc> &Ops,
                                   raw_ostream &OS) {
  // Collect Names.
  SequenceToOffsetTable<std::string> OpClassStrings;
  SequenceToOffsetTable<std::string> OpStrings;
  SequenceToOffsetTable<SmallVector<ParameterKind>> Parameters;

  StringMap<SmallVector<ParameterKind>> ParameterMap;
  StringSet<> ClassSet;
  for (auto &Op : Ops) {
    OpStrings.add(Op.OpName);

    if (ClassSet.contains(Op.OpClass))
      continue;
    ClassSet.insert(Op.OpClass);
    OpClassStrings.add(Op.OpClass.data());
    SmallVector<ParameterKind> ParamKindVec;
    // ParamKindVec is a vector of parameters. Skip return type at index 0
    for (unsigned i = 1; i < Op.OpTypes.size(); i++) {
      ParamKindVec.emplace_back(getParameterKind(Op.OpTypes[i]));
    }
    ParameterMap[Op.OpClass] = ParamKindVec;
    Parameters.add(ParamKindVec);
  }

  // Layout names.
  OpStrings.layout();
  OpClassStrings.layout();
  Parameters.layout();

  // Emit access function getOpcodeProperty() that embeds DXIL Operation table
  // with entries of type struct OpcodeProperty.
  OS << "static const OpCodeProperty *getOpCodeProperty(dxil::OpCode Op) "
        "{\n";

  OS << "  static const OpCodeProperty OpCodeProps[] = {\n";
  std::string Prefix = "";
  for (auto &Op : Ops) {
    // Consider Op.OverloadParamIndex as the overload parameter index, by
    // default
    auto OLParamIdx = Op.OverloadParamIndex;
    // If no overload parameter index is set, treat first parameter type as
    // overload type - unless the Op has no parameters, in which case treat the
    // return type - as overload parameter to emit the appropriate overload kind
    // enum.
    if (OLParamIdx < 0) {
      OLParamIdx = (Op.OpTypes.size() > 1) ? 1 : 0;
    }
    OS << Prefix << "  { dxil::OpCode::" << Op.OpName << ", "
       << OpStrings.get(Op.OpName) << ", OpCodeClass::" << Op.OpClass << ", "
       << OpClassStrings.get(Op.OpClass.data()) << ", "
       << getOverloadMaskString(Op.OverloadRecs) << ", "
       << getStageMaskString(Op.StageRecs) << ", "
       << getAttributeMaskString(Op.AttrRecs) << ", " << Op.OverloadParamIndex
       << ", " << Op.OpTypes.size() - 1 << ", "
       << Parameters.get(ParameterMap[Op.OpClass]) << " }";
    Prefix = ",\n";
  }
  OS << "  };\n";

  OS << "  // FIXME: change search to indexing with\n";
  OS << "  // Op once all DXIL operations are added.\n";
  OS << "  OpCodeProperty TmpProp;\n";
  OS << "  TmpProp.OpCode = Op;\n";
  OS << "  const OpCodeProperty *Prop =\n";
  OS << "      llvm::lower_bound(OpCodeProps, TmpProp,\n";
  OS << "                        [](const OpCodeProperty &A, const "
        "OpCodeProperty &B) {\n";
  OS << "                          return A.OpCode < B.OpCode;\n";
  OS << "                        });\n";
  OS << "  assert(Prop && \"failed to find OpCodeProperty\");\n";
  OS << "  return Prop;\n";
  OS << "}\n\n";

  // Emit the string tables.
  OS << "static const char *getOpCodeName(dxil::OpCode Op) {\n\n";

  OpStrings.emitStringLiteralDef(OS,
                                 "  static const char DXILOpCodeNameTable[]");

  OS << "  auto *Prop = getOpCodeProperty(Op);\n";
  OS << "  unsigned Index = Prop->OpCodeNameOffset;\n";
  OS << "  return DXILOpCodeNameTable + Index;\n";
  OS << "}\n\n";

  OS << "static const char *getOpCodeClassName(const OpCodeProperty &Prop) "
        "{\n\n";

  OpClassStrings.emitStringLiteralDef(
      OS, "  static const char DXILOpCodeClassNameTable[]");

  OS << "  unsigned Index = Prop.OpCodeClassNameOffset;\n";
  OS << "  return DXILOpCodeClassNameTable + Index;\n";
  OS << "}\n ";

  OS << "static const ParameterKind *getOpCodeParameterKind(const "
        "OpCodeProperty &Prop) "
        "{\n\n";
  OS << "  static const ParameterKind DXILOpParameterKindTable[] = {\n";
  Parameters.emit(
      OS,
      [](raw_ostream &ParamOS, ParameterKind Kind) {
        ParamOS << "ParameterKind::" << getParameterKindStr(Kind);
      },
      "ParameterKind::Invalid");
  OS << "  };\n\n";
  OS << "  unsigned Index = Prop.ParameterTableOffset;\n";
  OS << "  return DXILOpParameterKindTable + Index;\n";
  OS << "}\n\n";
}

static void emitDXILOperationTableDataStructs(RecordKeeper &Records,
                                              raw_ostream &OS) {
  // Get Shader stage records
  std::vector<Record *> ShaderKindRecs =
      Records.getAllDerivedDefinitions("DXILShaderStage");
  // Sort records by name
  llvm::sort(ShaderKindRecs,
             [](Record *A, Record *B) { return A->getName() < B->getName(); });

  OS << "// Valid shader kinds\n\n";
  // Choose the type of enum ShaderKind based on the number of stages declared.
  // This gives the flexibility to just add add new stage records in DXIL.td, if
  // needed, with no need to change this backend code.
  size_t ShaderKindCount = ShaderKindRecs.size();
  uint64_t ShaderKindTySz = PowerOf2Ceil(ShaderKindRecs.size() + 1);
  OS << "enum ShaderKind : uint" << ShaderKindTySz << "_t {\n";
  const std::string allStages("all_stages");
  const std::string removed("removed");
  int shiftVal = 1;
  for (auto R : ShaderKindRecs) {
    auto Name = R->getName();
    if (Name.compare(removed) == 0) {
      OS << "  " << Name
         << " =  0,  // Pseudo-stage indicating op not supported in any "
            "stage\n";
    } else if (Name.compare(allStages) == 0) {
      OS << "  " << Name << " =  0x"
         << utohexstr(((1 << ShaderKindCount) - 1), false, 0)
         << ", // Pseudo-stage indicating op is supported in all stages\n";
    } else if (Name.compare(allStages)) {
      OS << "  " << Name << " = 1 << " << std::to_string(shiftVal++) << ",\n";
    }
  }
  OS << "}; // enum ShaderKind\n\n";
}

/// Entry function call that invokes the functionality of this TableGen backend
/// \param Records TableGen records of DXIL Operations defined in DXIL.td
/// \param OS output stream
static void EmitDXILOperation(RecordKeeper &Records, raw_ostream &OS) {
  OS << "// Generated code, do not edit.\n";
  OS << "\n";
  // Get all DXIL Ops property records
  std::vector<Record *> OpIntrProps =
      Records.getAllDerivedDefinitions("DXILOp");
  std::vector<DXILOperationDesc> DXILOps;
  for (auto *Record : OpIntrProps) {
    DXILOps.emplace_back(DXILOperationDesc(Record));
  }
  // Sort by opcode.
  llvm::sort(DXILOps, [](DXILOperationDesc &A, DXILOperationDesc &B) {
    return A.OpCode < B.OpCode;
  });
  int PrevOp = -1;
  for (DXILOperationDesc &Desc : DXILOps) {
    if (Desc.OpCode == PrevOp)
      PrintFatalError(Twine("Duplicate opcode: ") + Twine(Desc.OpCode));
    PrevOp = Desc.OpCode;
  }

  emitDXILEnums(DXILOps, OS);
  emitDXILIntrinsicMap(DXILOps, OS);
  OS << "#ifdef DXIL_OP_OPERATION_TABLE\n\n";
  emitDXILOperationTableDataStructs(Records, OS);
  emitDXILOperationTable(DXILOps, OS);
  OS << "#undef DXIL_OP_OPERATION_TABLE\n";
  OS << "#endif\n\n";
}

static TableGen::Emitter::Opt X("gen-dxil-operation", EmitDXILOperation,
                                "Generate DXIL operation information");