xref: /llvm-project-15.0.7/mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp (revision b9378690)

//===- LLVMDialect.cpp - LLVM IR Ops and Dialect registration -------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines the types and operation details for the LLVM IR dialect in
// MLIR, and the LLVM IR dialect.  It also registers the dialect.
//
//===----------------------------------------------------------------------===//
#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
#include "mlir/Dialect/LLVMIR/LLVMTypes.h"
#include "mlir/IR/Builders.h"
#include "mlir/IR/BuiltinOps.h"
#include "mlir/IR/BuiltinTypes.h"
#include "mlir/IR/DialectImplementation.h"
#include "mlir/IR/FunctionImplementation.h"
#include "mlir/IR/MLIRContext.h"

#include "llvm/ADT/StringSwitch.h"
#include "llvm/AsmParser/Parser.h"
#include "llvm/Bitcode/BitcodeReader.h"
#include "llvm/Bitcode/BitcodeWriter.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Support/SourceMgr.h"

using namespace mlir;
using namespace mlir::LLVM;

static constexpr const char kVolatileAttrName[] = "volatile_";
static constexpr const char kNonTemporalAttrName[] = "nontemporal";

#include "mlir/Dialect/LLVMIR/LLVMOpsEnums.cpp.inc"
#include "mlir/Dialect/LLVMIR/LLVMOpsInterfaces.cpp.inc"

namespace mlir {
namespace LLVM {
namespace detail {
struct BitmaskEnumStorage : public AttributeStorage {
  using KeyTy = uint64_t;

  BitmaskEnumStorage(KeyTy val) : value(val) {}

  bool operator==(const KeyTy &key) const { return value == key; }

  static BitmaskEnumStorage *construct(AttributeStorageAllocator &allocator,
                                       const KeyTy &key) {
    return new (allocator.allocate<BitmaskEnumStorage>())
        BitmaskEnumStorage(key);
  }

  KeyTy value = 0;
};
} // namespace detail
} // namespace LLVM
} // namespace mlir

static auto processFMFAttr(ArrayRef<NamedAttribute> attrs) {
  SmallVector<NamedAttribute, 8> filteredAttrs(
      llvm::make_filter_range(attrs, [&](NamedAttribute attr) {
        if (attr.first == "fastmathFlags") {
          auto defAttr = FMFAttr::get({}, attr.second.getContext());
          return defAttr != attr.second;
        }
        return true;
      }));
  return filteredAttrs;
}

static ParseResult parseLLVMOpAttrs(OpAsmParser &parser,
                                    NamedAttrList &result) {
  return parser.parseOptionalAttrDict(result);
}

static void printLLVMOpAttrs(OpAsmPrinter &printer, Operation *op,
                             DictionaryAttr attrs) {
  printer.printOptionalAttrDict(processFMFAttr(attrs.getValue()));
}

//===----------------------------------------------------------------------===//
// Printing/parsing for LLVM::CmpOp.
//===----------------------------------------------------------------------===//
static void printICmpOp(OpAsmPrinter &p, ICmpOp &op) {
  p << op.getOperationName() << " \"" << stringifyICmpPredicate(op.predicate())
    << "\" " << op.getOperand(0) << ", " << op.getOperand(1);
  p.printOptionalAttrDict(op.getAttrs(), {"predicate"});
  p << " : " << op.lhs().getType();
}

static void printFCmpOp(OpAsmPrinter &p, FCmpOp &op) {
  p << op.getOperationName() << " \"" << stringifyFCmpPredicate(op.predicate())
    << "\" " << op.getOperand(0) << ", " << op.getOperand(1);
  p.printOptionalAttrDict(processFMFAttr(op.getAttrs()), {"predicate"});
  p << " : " << op.lhs().getType();
}

// <operation> ::= `llvm.icmp` string-literal ssa-use `,` ssa-use
//                 attribute-dict? `:` type
// <operation> ::= `llvm.fcmp` string-literal ssa-use `,` ssa-use
//                 attribute-dict? `:` type
template <typename CmpPredicateType>
static ParseResult parseCmpOp(OpAsmParser &parser, OperationState &result) {
  Builder &builder = parser.getBuilder();

  StringAttr predicateAttr;
  OpAsmParser::OperandType lhs, rhs;
  Type type;
  llvm::SMLoc predicateLoc, trailingTypeLoc;
  if (parser.getCurrentLocation(&predicateLoc) ||
      parser.parseAttribute(predicateAttr, "predicate", result.attributes) ||
      parser.parseOperand(lhs) || parser.parseComma() ||
      parser.parseOperand(rhs) ||
      parser.parseOptionalAttrDict(result.attributes) || parser.parseColon() ||
      parser.getCurrentLocation(&trailingTypeLoc) || parser.parseType(type) ||
      parser.resolveOperand(lhs, type, result.operands) ||
      parser.resolveOperand(rhs, type, result.operands))
    return failure();

  // Replace the string attribute `predicate` with an integer attribute.
  int64_t predicateValue = 0;
  if (std::is_same<CmpPredicateType, ICmpPredicate>()) {
    Optional<ICmpPredicate> predicate =
        symbolizeICmpPredicate(predicateAttr.getValue());
    if (!predicate)
      return parser.emitError(predicateLoc)
             << "'" << predicateAttr.getValue()
             << "' is an incorrect value of the 'predicate' attribute";
    predicateValue = static_cast<int64_t>(predicate.getValue());
  } else {
    Optional<FCmpPredicate> predicate =
        symbolizeFCmpPredicate(predicateAttr.getValue());
    if (!predicate)
      return parser.emitError(predicateLoc)
             << "'" << predicateAttr.getValue()
             << "' is an incorrect value of the 'predicate' attribute";
    predicateValue = static_cast<int64_t>(predicate.getValue());
  }

  result.attributes.set("predicate",
                        parser.getBuilder().getI64IntegerAttr(predicateValue));

  // The result type is either i1 or a vector type <? x i1> if the inputs are
  // vectors.
  Type resultType = IntegerType::get(builder.getContext(), 1);
  if (!isCompatibleType(type))
    return parser.emitError(trailingTypeLoc,
                            "expected LLVM dialect-compatible type");
  if (LLVM::isCompatibleVectorType(type))
    resultType = LLVM::getFixedVectorType(
        resultType, LLVM::getVectorNumElements(type).getFixedValue());
  assert(!type.isa<LLVM::LLVMScalableVectorType>() &&
         "unhandled scalable vector");

  result.addTypes({resultType});
  return success();
}

//===----------------------------------------------------------------------===//
// Printing/parsing for LLVM::AllocaOp.
//===----------------------------------------------------------------------===//

static void printAllocaOp(OpAsmPrinter &p, AllocaOp &op) {
  auto elemTy = op.getType().cast<LLVM::LLVMPointerType>().getElementType();

  auto funcTy = FunctionType::get(op.getContext(), {op.arraySize().getType()},
                                  {op.getType()});

  p << op.getOperationName() << ' ' << op.arraySize() << " x " << elemTy;
  if (op.alignment().hasValue() && *op.alignment() != 0)
    p.printOptionalAttrDict(op.getAttrs());
  else
    p.printOptionalAttrDict(op.getAttrs(), {"alignment"});
  p << " : " << funcTy;
}

// <operation> ::= `llvm.alloca` ssa-use `x` type attribute-dict?
//                 `:` type `,` type
static ParseResult parseAllocaOp(OpAsmParser &parser, OperationState &result) {
  OpAsmParser::OperandType arraySize;
  Type type, elemType;
  llvm::SMLoc trailingTypeLoc;
  if (parser.parseOperand(arraySize) || parser.parseKeyword("x") ||
      parser.parseType(elemType) ||
      parser.parseOptionalAttrDict(result.attributes) || parser.parseColon() ||
      parser.getCurrentLocation(&trailingTypeLoc) || parser.parseType(type))
    return failure();

  Optional<NamedAttribute> alignmentAttr =
      result.attributes.getNamed("alignment");
  if (alignmentAttr.hasValue()) {
    auto alignmentInt = alignmentAttr.getValue().second.dyn_cast<IntegerAttr>();
    if (!alignmentInt)
      return parser.emitError(parser.getNameLoc(),
                              "expected integer alignment");
    if (alignmentInt.getValue().isNullValue())
      result.attributes.erase("alignment");
  }

  // Extract the result type from the trailing function type.
  auto funcType = type.dyn_cast<FunctionType>();
  if (!funcType || funcType.getNumInputs() != 1 ||
      funcType.getNumResults() != 1)
    return parser.emitError(
        trailingTypeLoc,
        "expected trailing function type with one argument and one result");

  if (parser.resolveOperand(arraySize, funcType.getInput(0), result.operands))
    return failure();

  result.addTypes({funcType.getResult(0)});
  return success();
}

//===----------------------------------------------------------------------===//
// LLVM::BrOp
//===----------------------------------------------------------------------===//

Optional<MutableOperandRange>
BrOp::getMutableSuccessorOperands(unsigned index) {
  assert(index == 0 && "invalid successor index");
  return destOperandsMutable();
}

//===----------------------------------------------------------------------===//
// LLVM::CondBrOp
//===----------------------------------------------------------------------===//

Optional<MutableOperandRange>
CondBrOp::getMutableSuccessorOperands(unsigned index) {
  assert(index < getNumSuccessors() && "invalid successor index");
  return index == 0 ? trueDestOperandsMutable() : falseDestOperandsMutable();
}

//===----------------------------------------------------------------------===//
// LLVM::SwitchOp
//===----------------------------------------------------------------------===//

void SwitchOp::build(OpBuilder &builder, OperationState &result, Value value,
                     Block *defaultDestination, ValueRange defaultOperands,
                     ArrayRef<int32_t> caseValues, BlockRange caseDestinations,
                     ArrayRef<ValueRange> caseOperands,
                     ArrayRef<int32_t> branchWeights) {
  SmallVector<Value> flattenedCaseOperands;
  SmallVector<int32_t> caseOperandOffsets;
  int32_t offset = 0;
  for (ValueRange operands : caseOperands) {
    flattenedCaseOperands.append(operands.begin(), operands.end());
    caseOperandOffsets.push_back(offset);
    offset += operands.size();
  }
  ElementsAttr caseValuesAttr;
  if (!caseValues.empty())
    caseValuesAttr = builder.getI32VectorAttr(caseValues);
  ElementsAttr caseOperandOffsetsAttr;
  if (!caseOperandOffsets.empty())
    caseOperandOffsetsAttr = builder.getI32VectorAttr(caseOperandOffsets);

  ElementsAttr weightsAttr;
  if (!branchWeights.empty())
    weightsAttr = builder.getI32VectorAttr(llvm::to_vector<4>(branchWeights));

  build(builder, result, value, defaultOperands, flattenedCaseOperands,
        caseValuesAttr, caseOperandOffsetsAttr, weightsAttr, defaultDestination,
        caseDestinations);
}

/// <cases> ::= integer `:` bb-id (`(` ssa-use-and-type-list `)`)?
///             ( `,` integer `:` bb-id (`(` ssa-use-and-type-list `)`)? )?
static ParseResult
parseSwitchOpCases(OpAsmParser &parser, ElementsAttr &caseValues,
                   SmallVectorImpl<Block *> &caseDestinations,
                   SmallVectorImpl<OpAsmParser::OperandType> &caseOperands,
                   SmallVectorImpl<Type> &caseOperandTypes,
                   ElementsAttr &caseOperandOffsets) {
  SmallVector<int32_t> values;
  SmallVector<int32_t> offsets;
  int32_t value, offset = 0;
  do {
    OptionalParseResult integerParseResult = parser.parseOptionalInteger(value);
    if (values.empty() && !integerParseResult.hasValue())
      return success();

    if (!integerParseResult.hasValue() || integerParseResult.getValue())
      return failure();
    values.push_back(value);

    Block *destination;
    SmallVector<OpAsmParser::OperandType> operands;
    if (parser.parseColon() || parser.parseSuccessor(destination))
      return failure();
    if (!parser.parseOptionalLParen()) {
      if (parser.parseRegionArgumentList(operands) ||
          parser.parseColonTypeList(caseOperandTypes) || parser.parseRParen())
        return failure();
    }
    caseDestinations.push_back(destination);
    caseOperands.append(operands.begin(), operands.end());
    offsets.push_back(offset);
    offset += operands.size();
  } while (!parser.parseOptionalComma());

  Builder &builder = parser.getBuilder();
  caseValues = builder.getI32VectorAttr(values);
  caseOperandOffsets = builder.getI32VectorAttr(offsets);

  return success();
}

static void printSwitchOpCases(OpAsmPrinter &p, SwitchOp op,
                               ElementsAttr caseValues,
                               SuccessorRange caseDestinations,
                               OperandRange caseOperands,
                               TypeRange caseOperandTypes,
                               ElementsAttr caseOperandOffsets) {
  if (!caseValues)
    return;

  size_t index = 0;
  llvm::interleave(
      llvm::zip(caseValues.cast<DenseIntElementsAttr>(), caseDestinations),
      [&](auto i) {
        p << "  ";
        p << std::get<0>(i).getLimitedValue();
        p << ": ";
        p.printSuccessorAndUseList(std::get<1>(i), op.getCaseOperands(index++));
      },
      [&] {
        p << ',';
        p.printNewline();
      });
  p.printNewline();
}

static LogicalResult verify(SwitchOp op) {
  if ((!op.case_values() && !op.caseDestinations().empty()) ||
      (op.case_values() &&
       op.case_values()->size() !=
           static_cast<int64_t>(op.caseDestinations().size())))
    return op.emitOpError("expects number of case values to match number of "
                          "case destinations");
  if (op.branch_weights() &&
      op.branch_weights()->size() != op.getNumSuccessors())
    return op.emitError("expects number of branch weights to match number of "
                        "successors: ")
           << op.branch_weights()->size() << " vs " << op.getNumSuccessors();
  return success();
}

OperandRange SwitchOp::getCaseOperands(unsigned index) {
  return getCaseOperandsMutable(index);
}

MutableOperandRange SwitchOp::getCaseOperandsMutable(unsigned index) {
  MutableOperandRange caseOperands = caseOperandsMutable();
  if (!case_operand_offsets()) {
    assert(caseOperands.size() == 0 &&
           "non-empty case operands must have offsets");
    return caseOperands;
  }

  ElementsAttr offsets = case_operand_offsets().getValue();
  assert(index < offsets.size() && "invalid case operand offset index");

  int64_t begin = offsets.getValue(index).cast<IntegerAttr>().getInt();
  int64_t end = index + 1 == offsets.size()
                    ? caseOperands.size()
                    : offsets.getValue(index + 1).cast<IntegerAttr>().getInt();
  return caseOperandsMutable().slice(begin, end - begin);
}

Optional<MutableOperandRange>
SwitchOp::getMutableSuccessorOperands(unsigned index) {
  assert(index < getNumSuccessors() && "invalid successor index");
  return index == 0 ? defaultOperandsMutable()
                    : getCaseOperandsMutable(index - 1);
}

//===----------------------------------------------------------------------===//
// Builder, printer and parser for for LLVM::LoadOp.
//===----------------------------------------------------------------------===//

void LoadOp::build(OpBuilder &builder, OperationState &result, Type t,
                   Value addr, unsigned alignment, bool isVolatile,
                   bool isNonTemporal) {
  result.addOperands(addr);
  result.addTypes(t);
  if (isVolatile)
    result.addAttribute(kVolatileAttrName, builder.getUnitAttr());
  if (isNonTemporal)
    result.addAttribute(kNonTemporalAttrName, builder.getUnitAttr());
  if (alignment != 0)
    result.addAttribute("alignment", builder.getI64IntegerAttr(alignment));
}

static void printLoadOp(OpAsmPrinter &p, LoadOp &op) {
  p << op.getOperationName() << ' ';
  if (op.volatile_())
    p << "volatile ";
  p << op.addr();
  p.printOptionalAttrDict(op.getAttrs(), {kVolatileAttrName});
  p << " : " << op.addr().getType();
}

// Extract the pointee type from the LLVM pointer type wrapped in MLIR.  Return
// the resulting type wrapped in MLIR, or nullptr on error.
static Type getLoadStoreElementType(OpAsmParser &parser, Type type,
                                    llvm::SMLoc trailingTypeLoc) {
  auto llvmTy = type.dyn_cast<LLVM::LLVMPointerType>();
  if (!llvmTy)
    return parser.emitError(trailingTypeLoc, "expected LLVM pointer type"),
           nullptr;
  return llvmTy.getElementType();
}

// <operation> ::= `llvm.load` `volatile` ssa-use attribute-dict? `:` type
static ParseResult parseLoadOp(OpAsmParser &parser, OperationState &result) {
  OpAsmParser::OperandType addr;
  Type type;
  llvm::SMLoc trailingTypeLoc;

  if (succeeded(parser.parseOptionalKeyword("volatile")))
    result.addAttribute(kVolatileAttrName, parser.getBuilder().getUnitAttr());

  if (parser.parseOperand(addr) ||
      parser.parseOptionalAttrDict(result.attributes) || parser.parseColon() ||
      parser.getCurrentLocation(&trailingTypeLoc) || parser.parseType(type) ||
      parser.resolveOperand(addr, type, result.operands))
    return failure();

  Type elemTy = getLoadStoreElementType(parser, type, trailingTypeLoc);

  result.addTypes(elemTy);
  return success();
}

//===----------------------------------------------------------------------===//
// Builder, printer and parser for LLVM::StoreOp.
//===----------------------------------------------------------------------===//

void StoreOp::build(OpBuilder &builder, OperationState &result, Value value,
                    Value addr, unsigned alignment, bool isVolatile,
                    bool isNonTemporal) {
  result.addOperands({value, addr});
  result.addTypes({});
  if (isVolatile)
    result.addAttribute(kVolatileAttrName, builder.getUnitAttr());
  if (isNonTemporal)
    result.addAttribute(kNonTemporalAttrName, builder.getUnitAttr());
  if (alignment != 0)
    result.addAttribute("alignment", builder.getI64IntegerAttr(alignment));
}

static void printStoreOp(OpAsmPrinter &p, StoreOp &op) {
  p << op.getOperationName() << ' ';
  if (op.volatile_())
    p << "volatile ";
  p << op.value() << ", " << op.addr();
  p.printOptionalAttrDict(op.getAttrs(), {kVolatileAttrName});
  p << " : " << op.addr().getType();
}

// <operation> ::= `llvm.store` `volatile` ssa-use `,` ssa-use
//                 attribute-dict? `:` type
static ParseResult parseStoreOp(OpAsmParser &parser, OperationState &result) {
  OpAsmParser::OperandType addr, value;
  Type type;
  llvm::SMLoc trailingTypeLoc;

  if (succeeded(parser.parseOptionalKeyword("volatile")))
    result.addAttribute(kVolatileAttrName, parser.getBuilder().getUnitAttr());

  if (parser.parseOperand(value) || parser.parseComma() ||
      parser.parseOperand(addr) ||
      parser.parseOptionalAttrDict(result.attributes) || parser.parseColon() ||
      parser.getCurrentLocation(&trailingTypeLoc) || parser.parseType(type))
    return failure();

  Type elemTy = getLoadStoreElementType(parser, type, trailingTypeLoc);
  if (!elemTy)
    return failure();

  if (parser.resolveOperand(value, elemTy, result.operands) ||
      parser.resolveOperand(addr, type, result.operands))
    return failure();

  return success();
}

///===---------------------------------------------------------------------===//
/// LLVM::InvokeOp
///===---------------------------------------------------------------------===//

Optional<MutableOperandRange>
InvokeOp::getMutableSuccessorOperands(unsigned index) {
  assert(index < getNumSuccessors() && "invalid successor index");
  return index == 0 ? normalDestOperandsMutable() : unwindDestOperandsMutable();
}

static LogicalResult verify(InvokeOp op) {
  if (op.getNumResults() > 1)
    return op.emitOpError("must have 0 or 1 result");

  Block *unwindDest = op.unwindDest();
  if (unwindDest->empty())
    return op.emitError(
        "must have at least one operation in unwind destination");

  // In unwind destination, first operation must be LandingpadOp
  if (!isa<LandingpadOp>(unwindDest->front()))
    return op.emitError("first operation in unwind destination should be a "
                        "llvm.landingpad operation");

  return success();
}

static void printInvokeOp(OpAsmPrinter &p, InvokeOp op) {
  auto callee = op.callee();
  bool isDirect = callee.hasValue();

  p << op.getOperationName() << ' ';

  // Either function name or pointer
  if (isDirect)
    p.printSymbolName(callee.getValue());
  else
    p << op.getOperand(0);

  p << '(' << op.getOperands().drop_front(isDirect ? 0 : 1) << ')';
  p << " to ";
  p.printSuccessorAndUseList(op.normalDest(), op.normalDestOperands());
  p << " unwind ";
  p.printSuccessorAndUseList(op.unwindDest(), op.unwindDestOperands());

  p.printOptionalAttrDict(op.getAttrs(),
                          {InvokeOp::getOperandSegmentSizeAttr(), "callee"});
  p << " : ";
  p.printFunctionalType(
      llvm::drop_begin(op.getOperandTypes(), isDirect ? 0 : 1),
      op.getResultTypes());
}

/// <operation> ::= `llvm.invoke` (function-id | ssa-use) `(` ssa-use-list `)`
///                  `to` bb-id (`[` ssa-use-and-type-list `]`)?
///                  `unwind` bb-id (`[` ssa-use-and-type-list `]`)?
///                  attribute-dict? `:` function-type
static ParseResult parseInvokeOp(OpAsmParser &parser, OperationState &result) {
  SmallVector<OpAsmParser::OperandType, 8> operands;
  FunctionType funcType;
  SymbolRefAttr funcAttr;
  llvm::SMLoc trailingTypeLoc;
  Block *normalDest, *unwindDest;
  SmallVector<Value, 4> normalOperands, unwindOperands;
  Builder &builder = parser.getBuilder();

  // Parse an operand list that will, in practice, contain 0 or 1 operand.  In
  // case of an indirect call, there will be 1 operand before `(`.  In case of a
  // direct call, there will be no operands and the parser will stop at the
  // function identifier without complaining.
  if (parser.parseOperandList(operands))
    return failure();
  bool isDirect = operands.empty();

  // Optionally parse a function identifier.
  if (isDirect && parser.parseAttribute(funcAttr, "callee", result.attributes))
    return failure();

  if (parser.parseOperandList(operands, OpAsmParser::Delimiter::Paren) ||
      parser.parseKeyword("to") ||
      parser.parseSuccessorAndUseList(normalDest, normalOperands) ||
      parser.parseKeyword("unwind") ||
      parser.parseSuccessorAndUseList(unwindDest, unwindOperands) ||
      parser.parseOptionalAttrDict(result.attributes) || parser.parseColon() ||
      parser.getCurrentLocation(&trailingTypeLoc) || parser.parseType(funcType))
    return failure();

  if (isDirect) {
    // Make sure types match.
    if (parser.resolveOperands(operands, funcType.getInputs(),
                               parser.getNameLoc(), result.operands))
      return failure();
    result.addTypes(funcType.getResults());
  } else {
    // Construct the LLVM IR Dialect function type that the first operand
    // should match.
    if (funcType.getNumResults() > 1)
      return parser.emitError(trailingTypeLoc,
                              "expected function with 0 or 1 result");

    Type llvmResultType;
    if (funcType.getNumResults() == 0) {
      llvmResultType = LLVM::LLVMVoidType::get(builder.getContext());
    } else {
      llvmResultType = funcType.getResult(0);
      if (!isCompatibleType(llvmResultType))
        return parser.emitError(trailingTypeLoc,
                                "expected result to have LLVM type");
    }

    SmallVector<Type, 8> argTypes;
    argTypes.reserve(funcType.getNumInputs());
    for (Type ty : funcType.getInputs()) {
      if (isCompatibleType(ty))
        argTypes.push_back(ty);
      else
        return parser.emitError(trailingTypeLoc,
                                "expected LLVM types as inputs");
    }

    auto llvmFuncType = LLVM::LLVMFunctionType::get(llvmResultType, argTypes);
    auto wrappedFuncType = LLVM::LLVMPointerType::get(llvmFuncType);

    auto funcArguments = llvm::makeArrayRef(operands).drop_front();

    // Make sure that the first operand (indirect callee) matches the wrapped
    // LLVM IR function type, and that the types of the other call operands
    // match the types of the function arguments.
    if (parser.resolveOperand(operands[0], wrappedFuncType, result.operands) ||
        parser.resolveOperands(funcArguments, funcType.getInputs(),
                               parser.getNameLoc(), result.operands))
      return failure();

    result.addTypes(llvmResultType);
  }
  result.addSuccessors({normalDest, unwindDest});
  result.addOperands(normalOperands);
  result.addOperands(unwindOperands);

  result.addAttribute(
      InvokeOp::getOperandSegmentSizeAttr(),
      builder.getI32VectorAttr({static_cast<int32_t>(operands.size()),
                                static_cast<int32_t>(normalOperands.size()),
                                static_cast<int32_t>(unwindOperands.size())}));
  return success();
}

///===----------------------------------------------------------------------===//
/// Verifying/Printing/Parsing for LLVM::LandingpadOp.
///===----------------------------------------------------------------------===//

static LogicalResult verify(LandingpadOp op) {
  Value value;
  if (LLVMFuncOp func = op->getParentOfType<LLVMFuncOp>()) {
    if (!func.personality().hasValue())
      return op.emitError(
          "llvm.landingpad needs to be in a function with a personality");
  }

  if (!op.cleanup() && op.getOperands().empty())
    return op.emitError("landingpad instruction expects at least one clause or "
                        "cleanup attribute");

  for (unsigned idx = 0, ie = op.getNumOperands(); idx < ie; idx++) {
    value = op.getOperand(idx);
    bool isFilter = value.getType().isa<LLVMArrayType>();
    if (isFilter) {
      // FIXME: Verify filter clauses when arrays are appropriately handled
    } else {
      // catch - global addresses only.
      // Bitcast ops should have global addresses as their args.
      if (auto bcOp = value.getDefiningOp<BitcastOp>()) {
        if (auto addrOp = bcOp.arg().getDefiningOp<AddressOfOp>())
          continue;
        return op.emitError("constant clauses expected")
                   .attachNote(bcOp.getLoc())
               << "global addresses expected as operand to "
                  "bitcast used in clauses for landingpad";
      }
      // NullOp and AddressOfOp allowed
      if (value.getDefiningOp<NullOp>())
        continue;
      if (value.getDefiningOp<AddressOfOp>())
        continue;
      return op.emitError("clause #")
             << idx << " is not a known constant - null, addressof, bitcast";
    }
  }
  return success();
}

static void printLandingpadOp(OpAsmPrinter &p, LandingpadOp &op) {
  p << op.getOperationName() << (op.cleanup() ? " cleanup " : " ");

  // Clauses
  for (auto value : op.getOperands()) {
    // Similar to llvm - if clause is an array type then it is filter
    // clause else catch clause
    bool isArrayTy = value.getType().isa<LLVMArrayType>();
    p << '(' << (isArrayTy ? "filter " : "catch ") << value << " : "
      << value.getType() << ") ";
  }

  p.printOptionalAttrDict(op.getAttrs(), {"cleanup"});

  p << ": " << op.getType();
}

/// <operation> ::= `llvm.landingpad` `cleanup`?
///                 ((`catch` | `filter`) operand-type ssa-use)* attribute-dict?
static ParseResult parseLandingpadOp(OpAsmParser &parser,
                                     OperationState &result) {
  // Check for cleanup
  if (succeeded(parser.parseOptionalKeyword("cleanup")))
    result.addAttribute("cleanup", parser.getBuilder().getUnitAttr());

  // Parse clauses with types
  while (succeeded(parser.parseOptionalLParen()) &&
         (succeeded(parser.parseOptionalKeyword("filter")) ||
          succeeded(parser.parseOptionalKeyword("catch")))) {
    OpAsmParser::OperandType operand;
    Type ty;
    if (parser.parseOperand(operand) || parser.parseColon() ||
        parser.parseType(ty) ||
        parser.resolveOperand(operand, ty, result.operands) ||
        parser.parseRParen())
      return failure();
  }

  Type type;
  if (parser.parseColon() || parser.parseType(type))
    return failure();

  result.addTypes(type);
  return success();
}

//===----------------------------------------------------------------------===//
// Verifying/Printing/parsing for LLVM::CallOp.
//===----------------------------------------------------------------------===//

static LogicalResult verify(CallOp &op) {
  if (op.getNumResults() > 1)
    return op.emitOpError("must have 0 or 1 result");

  // Type for the callee, we'll get it differently depending if it is a direct
  // or indirect call.
  Type fnType;

  bool isIndirect = false;

  // If this is an indirect call, the callee attribute is missing.
  Optional<StringRef> calleeName = op.callee();
  if (!calleeName) {
    isIndirect = true;
    if (!op.getNumOperands())
      return op.emitOpError(
          "must have either a `callee` attribute or at least an operand");
    auto ptrType = op.getOperand(0).getType().dyn_cast<LLVMPointerType>();
    if (!ptrType)
      return op.emitOpError("indirect call expects a pointer as callee: ")
             << ptrType;
    fnType = ptrType.getElementType();
  } else {
    Operation *callee = SymbolTable::lookupNearestSymbolFrom(op, *calleeName);
    if (!callee)
      return op.emitOpError()
             << "'" << *calleeName
             << "' does not reference a symbol in the current scope";
    auto fn = dyn_cast<LLVMFuncOp>(callee);
    if (!fn)
      return op.emitOpError() << "'" << *calleeName
                              << "' does not reference a valid LLVM function";

    fnType = fn.getType();
  }

  LLVMFunctionType funcType = fnType.dyn_cast<LLVMFunctionType>();
  if (!funcType)
    return op.emitOpError("callee does not have a functional type: ") << fnType;

  // Verify that the operand and result types match the callee.

  if (!funcType.isVarArg() &&
      funcType.getNumParams() != (op.getNumOperands() - isIndirect))
    return op.emitOpError()
           << "incorrect number of operands ("
           << (op.getNumOperands() - isIndirect)
           << ") for callee (expecting: " << funcType.getNumParams() << ")";

  if (funcType.getNumParams() > (op.getNumOperands() - isIndirect))
    return op.emitOpError() << "incorrect number of operands ("
                            << (op.getNumOperands() - isIndirect)
                            << ") for varargs callee (expecting at least: "
                            << funcType.getNumParams() << ")";

  for (unsigned i = 0, e = funcType.getNumParams(); i != e; ++i)
    if (op.getOperand(i + isIndirect).getType() != funcType.getParamType(i))
      return op.emitOpError() << "operand type mismatch for operand " << i
                              << ": " << op.getOperand(i + isIndirect).getType()
                              << " != " << funcType.getParamType(i);

  if (op.getNumResults() &&
      op.getResult(0).getType() != funcType.getReturnType())
    return op.emitOpError()
           << "result type mismatch: " << op.getResult(0).getType()
           << " != " << funcType.getReturnType();

  return success();
}

static void printCallOp(OpAsmPrinter &p, CallOp &op) {
  auto callee = op.callee();
  bool isDirect = callee.hasValue();

  // Print the direct callee if present as a function attribute, or an indirect
  // callee (first operand) otherwise.
  p << op.getOperationName() << ' ';
  if (isDirect)
    p.printSymbolName(callee.getValue());
  else
    p << op.getOperand(0);

  auto args = op.getOperands().drop_front(isDirect ? 0 : 1);
  p << '(' << args << ')';
  p.printOptionalAttrDict(processFMFAttr(op.getAttrs()), {"callee"});

  // Reconstruct the function MLIR function type from operand and result types.
  p << " : "
    << FunctionType::get(op.getContext(), args.getTypes(), op.getResultTypes());
}

// <operation> ::= `llvm.call` (function-id | ssa-use) `(` ssa-use-list `)`
//                 attribute-dict? `:` function-type
static ParseResult parseCallOp(OpAsmParser &parser, OperationState &result) {
  SmallVector<OpAsmParser::OperandType, 8> operands;
  Type type;
  SymbolRefAttr funcAttr;
  llvm::SMLoc trailingTypeLoc;

  // Parse an operand list that will, in practice, contain 0 or 1 operand.  In
  // case of an indirect call, there will be 1 operand before `(`.  In case of a
  // direct call, there will be no operands and the parser will stop at the
  // function identifier without complaining.
  if (parser.parseOperandList(operands))
    return failure();
  bool isDirect = operands.empty();

  // Optionally parse a function identifier.
  if (isDirect)
    if (parser.parseAttribute(funcAttr, "callee", result.attributes))
      return failure();

  if (parser.parseOperandList(operands, OpAsmParser::Delimiter::Paren) ||
      parser.parseOptionalAttrDict(result.attributes) || parser.parseColon() ||
      parser.getCurrentLocation(&trailingTypeLoc) || parser.parseType(type))
    return failure();

  auto funcType = type.dyn_cast<FunctionType>();
  if (!funcType)
    return parser.emitError(trailingTypeLoc, "expected function type");
  if (isDirect) {
    // Make sure types match.
    if (parser.resolveOperands(operands, funcType.getInputs(),
                               parser.getNameLoc(), result.operands))
      return failure();
    result.addTypes(funcType.getResults());
  } else {
    // Construct the LLVM IR Dialect function type that the first operand
    // should match.
    if (funcType.getNumResults() > 1)
      return parser.emitError(trailingTypeLoc,
                              "expected function with 0 or 1 result");

    Builder &builder = parser.getBuilder();
    Type llvmResultType;
    if (funcType.getNumResults() == 0) {
      llvmResultType = LLVM::LLVMVoidType::get(builder.getContext());
    } else {
      llvmResultType = funcType.getResult(0);
      if (!isCompatibleType(llvmResultType))
        return parser.emitError(trailingTypeLoc,
                                "expected result to have LLVM type");
    }

    SmallVector<Type, 8> argTypes;
    argTypes.reserve(funcType.getNumInputs());
    for (int i = 0, e = funcType.getNumInputs(); i < e; ++i) {
      auto argType = funcType.getInput(i);
      if (!isCompatibleType(argType))
        return parser.emitError(trailingTypeLoc,
                                "expected LLVM types as inputs");
      argTypes.push_back(argType);
    }
    auto llvmFuncType = LLVM::LLVMFunctionType::get(llvmResultType, argTypes);
    auto wrappedFuncType = LLVM::LLVMPointerType::get(llvmFuncType);

    auto funcArguments =
        ArrayRef<OpAsmParser::OperandType>(operands).drop_front();

    // Make sure that the first operand (indirect callee) matches the wrapped
    // LLVM IR function type, and that the types of the other call operands
    // match the types of the function arguments.
    if (parser.resolveOperand(operands[0], wrappedFuncType, result.operands) ||
        parser.resolveOperands(funcArguments, funcType.getInputs(),
                               parser.getNameLoc(), result.operands))
      return failure();

    result.addTypes(llvmResultType);
  }

  return success();
}

//===----------------------------------------------------------------------===//
// Printing/parsing for LLVM::ExtractElementOp.
//===----------------------------------------------------------------------===//
// Expects vector to be of wrapped LLVM vector type and position to be of
// wrapped LLVM i32 type.
void LLVM::ExtractElementOp::build(OpBuilder &b, OperationState &result,
                                   Value vector, Value position,
                                   ArrayRef<NamedAttribute> attrs) {
  auto vectorType = vector.getType();
  auto llvmType = LLVM::getVectorElementType(vectorType);
  build(b, result, llvmType, vector, position);
  result.addAttributes(attrs);
}

static void printExtractElementOp(OpAsmPrinter &p, ExtractElementOp &op) {
  p << op.getOperationName() << ' ' << op.vector() << "[" << op.position()
    << " : " << op.position().getType() << "]";
  p.printOptionalAttrDict(op.getAttrs());
  p << " : " << op.vector().getType();
}

// <operation> ::= `llvm.extractelement` ssa-use `, ` ssa-use
//                 attribute-dict? `:` type
static ParseResult parseExtractElementOp(OpAsmParser &parser,
                                         OperationState &result) {
  llvm::SMLoc loc;
  OpAsmParser::OperandType vector, position;
  Type type, positionType;
  if (parser.getCurrentLocation(&loc) || parser.parseOperand(vector) ||
      parser.parseLSquare() || parser.parseOperand(position) ||
      parser.parseColonType(positionType) || parser.parseRSquare() ||
      parser.parseOptionalAttrDict(result.attributes) ||
      parser.parseColonType(type) ||
      parser.resolveOperand(vector, type, result.operands) ||
      parser.resolveOperand(position, positionType, result.operands))
    return failure();
  if (!LLVM::isCompatibleVectorType(type))
    return parser.emitError(
        loc, "expected LLVM dialect-compatible vector type for operand #1");
  result.addTypes(LLVM::getVectorElementType(type));
  return success();
}

//===----------------------------------------------------------------------===//
// Printing/parsing for LLVM::ExtractValueOp.
//===----------------------------------------------------------------------===//

static void printExtractValueOp(OpAsmPrinter &p, ExtractValueOp &op) {
  p << op.getOperationName() << ' ' << op.container() << op.position();
  p.printOptionalAttrDict(op.getAttrs(), {"position"});
  p << " : " << op.container().getType();
}

// Extract the type at `position` in the wrapped LLVM IR aggregate type
// `containerType`.  Position is an integer array attribute where each value
// is a zero-based position of the element in the aggregate type.  Return the
// resulting type wrapped in MLIR, or nullptr on error.
static Type getInsertExtractValueElementType(OpAsmParser &parser,
                                             Type containerType,
                                             ArrayAttr positionAttr,
                                             llvm::SMLoc attributeLoc,
                                             llvm::SMLoc typeLoc) {
  Type llvmType = containerType;
  if (!isCompatibleType(containerType))
    return parser.emitError(typeLoc, "expected LLVM IR Dialect type"), nullptr;

  // Infer the element type from the structure type: iteratively step inside the
  // type by taking the element type, indexed by the position attribute for
  // structures.  Check the position index before accessing, it is supposed to
  // be in bounds.
  for (Attribute subAttr : positionAttr) {
    auto positionElementAttr = subAttr.dyn_cast<IntegerAttr>();
    if (!positionElementAttr)
      return parser.emitError(attributeLoc,
                              "expected an array of integer literals"),
             nullptr;
    int position = positionElementAttr.getInt();
    if (auto arrayType = llvmType.dyn_cast<LLVMArrayType>()) {
      if (position < 0 ||
          static_cast<unsigned>(position) >= arrayType.getNumElements())
        return parser.emitError(attributeLoc, "position out of bounds"),
               nullptr;
      llvmType = arrayType.getElementType();
    } else if (auto structType = llvmType.dyn_cast<LLVMStructType>()) {
      if (position < 0 ||
          static_cast<unsigned>(position) >= structType.getBody().size())
        return parser.emitError(attributeLoc, "position out of bounds"),
               nullptr;
      llvmType = structType.getBody()[position];
    } else {
      return parser.emitError(typeLoc, "expected LLVM IR structure/array type"),
             nullptr;
    }
  }
  return llvmType;
}

// <operation> ::= `llvm.extractvalue` ssa-use
//                 `[` integer-literal (`,` integer-literal)* `]`
//                 attribute-dict? `:` type
static ParseResult parseExtractValueOp(OpAsmParser &parser,
                                       OperationState &result) {
  OpAsmParser::OperandType container;
  Type containerType;
  ArrayAttr positionAttr;
  llvm::SMLoc attributeLoc, trailingTypeLoc;

  if (parser.parseOperand(container) ||
      parser.getCurrentLocation(&attributeLoc) ||
      parser.parseAttribute(positionAttr, "position", result.attributes) ||
      parser.parseOptionalAttrDict(result.attributes) || parser.parseColon() ||
      parser.getCurrentLocation(&trailingTypeLoc) ||
      parser.parseType(containerType) ||
      parser.resolveOperand(container, containerType, result.operands))
    return failure();

  auto elementType = getInsertExtractValueElementType(
      parser, containerType, positionAttr, attributeLoc, trailingTypeLoc);
  if (!elementType)
    return failure();

  result.addTypes(elementType);
  return success();
}

//===----------------------------------------------------------------------===//
// Printing/parsing for LLVM::InsertElementOp.
//===----------------------------------------------------------------------===//

static void printInsertElementOp(OpAsmPrinter &p, InsertElementOp &op) {
  p << op.getOperationName() << ' ' << op.value() << ", " << op.vector() << "["
    << op.position() << " : " << op.position().getType() << "]";
  p.printOptionalAttrDict(op.getAttrs());
  p << " : " << op.vector().getType();
}

// <operation> ::= `llvm.insertelement` ssa-use `,` ssa-use `,` ssa-use
//                 attribute-dict? `:` type
static ParseResult parseInsertElementOp(OpAsmParser &parser,
                                        OperationState &result) {
  llvm::SMLoc loc;
  OpAsmParser::OperandType vector, value, position;
  Type vectorType, positionType;
  if (parser.getCurrentLocation(&loc) || parser.parseOperand(value) ||
      parser.parseComma() || parser.parseOperand(vector) ||
      parser.parseLSquare() || parser.parseOperand(position) ||
      parser.parseColonType(positionType) || parser.parseRSquare() ||
      parser.parseOptionalAttrDict(result.attributes) ||
      parser.parseColonType(vectorType))
    return failure();

  if (!LLVM::isCompatibleVectorType(vectorType))
    return parser.emitError(
        loc, "expected LLVM dialect-compatible vector type for operand #1");
  Type valueType = LLVM::getVectorElementType(vectorType);
  if (!valueType)
    return failure();

  if (parser.resolveOperand(vector, vectorType, result.operands) ||
      parser.resolveOperand(value, valueType, result.operands) ||
      parser.resolveOperand(position, positionType, result.operands))
    return failure();

  result.addTypes(vectorType);
  return success();
}

//===----------------------------------------------------------------------===//
// Printing/parsing for LLVM::InsertValueOp.
//===----------------------------------------------------------------------===//

static void printInsertValueOp(OpAsmPrinter &p, InsertValueOp &op) {
  p << op.getOperationName() << ' ' << op.value() << ", " << op.container()
    << op.position();
  p.printOptionalAttrDict(op.getAttrs(), {"position"});
  p << " : " << op.container().getType();
}

// <operation> ::= `llvm.insertvaluevalue` ssa-use `,` ssa-use
//                 `[` integer-literal (`,` integer-literal)* `]`
//                 attribute-dict? `:` type
static ParseResult parseInsertValueOp(OpAsmParser &parser,
                                      OperationState &result) {
  OpAsmParser::OperandType container, value;
  Type containerType;
  ArrayAttr positionAttr;
  llvm::SMLoc attributeLoc, trailingTypeLoc;

  if (parser.parseOperand(value) || parser.parseComma() ||
      parser.parseOperand(container) ||
      parser.getCurrentLocation(&attributeLoc) ||
      parser.parseAttribute(positionAttr, "position", result.attributes) ||
      parser.parseOptionalAttrDict(result.attributes) || parser.parseColon() ||
      parser.getCurrentLocation(&trailingTypeLoc) ||
      parser.parseType(containerType))
    return failure();

  auto valueType = getInsertExtractValueElementType(
      parser, containerType, positionAttr, attributeLoc, trailingTypeLoc);
  if (!valueType)
    return failure();

  if (parser.resolveOperand(container, containerType, result.operands) ||
      parser.resolveOperand(value, valueType, result.operands))
    return failure();

  result.addTypes(containerType);
  return success();
}

//===----------------------------------------------------------------------===//
// Printing/parsing for LLVM::ReturnOp.
//===----------------------------------------------------------------------===//

static void printReturnOp(OpAsmPrinter &p, ReturnOp &op) {
  p << op.getOperationName();
  p.printOptionalAttrDict(op.getAttrs());
  assert(op.getNumOperands() <= 1);

  if (op.getNumOperands() == 0)
    return;

  p << ' ' << op.getOperand(0) << " : " << op.getOperand(0).getType();
}

// <operation> ::= `llvm.return` ssa-use-list attribute-dict? `:`
//                 type-list-no-parens
static ParseResult parseReturnOp(OpAsmParser &parser, OperationState &result) {
  SmallVector<OpAsmParser::OperandType, 1> operands;
  Type type;

  if (parser.parseOperandList(operands) ||
      parser.parseOptionalAttrDict(result.attributes))
    return failure();
  if (operands.empty())
    return success();

  if (parser.parseColonType(type) ||
      parser.resolveOperand(operands[0], type, result.operands))
    return failure();
  return success();
}

//===----------------------------------------------------------------------===//
// Verifier for LLVM::AddressOfOp.
//===----------------------------------------------------------------------===//

template <typename OpTy>
static OpTy lookupSymbolInModule(Operation *parent, StringRef name) {
  Operation *module = parent;
  while (module && !satisfiesLLVMModule(module))
    module = module->getParentOp();
  assert(module && "unexpected operation outside of a module");
  return dyn_cast_or_null<OpTy>(
      mlir::SymbolTable::lookupSymbolIn(module, name));
}

GlobalOp AddressOfOp::getGlobal() {
  return lookupSymbolInModule<LLVM::GlobalOp>((*this)->getParentOp(),
                                              global_name());
}

LLVMFuncOp AddressOfOp::getFunction() {
  return lookupSymbolInModule<LLVM::LLVMFuncOp>((*this)->getParentOp(),
                                                global_name());
}

static LogicalResult verify(AddressOfOp op) {
  auto global = op.getGlobal();
  auto function = op.getFunction();
  if (!global && !function)
    return op.emitOpError(
        "must reference a global defined by 'llvm.mlir.global' or 'llvm.func'");

  if (global &&
      LLVM::LLVMPointerType::get(global.getType(), global.addr_space()) !=
          op.getResult().getType())
    return op.emitOpError(
        "the type must be a pointer to the type of the referenced global");

  if (function && LLVM::LLVMPointerType::get(function.getType()) !=
                      op.getResult().getType())
    return op.emitOpError(
        "the type must be a pointer to the type of the referenced function");

  return success();
}

//===----------------------------------------------------------------------===//
// Builder, printer and verifier for LLVM::GlobalOp.
//===----------------------------------------------------------------------===//

/// Returns the name used for the linkage attribute. This *must* correspond to
/// the name of the attribute in ODS.
static StringRef getLinkageAttrName() { return "linkage"; }

void GlobalOp::build(OpBuilder &builder, OperationState &result, Type type,
                     bool isConstant, Linkage linkage, StringRef name,
                     Attribute value, unsigned addrSpace,
                     ArrayRef<NamedAttribute> attrs) {
  result.addAttribute(SymbolTable::getSymbolAttrName(),
                      builder.getStringAttr(name));
  result.addAttribute("type", TypeAttr::get(type));
  if (isConstant)
    result.addAttribute("constant", builder.getUnitAttr());
  if (value)
    result.addAttribute("value", value);
  result.addAttribute(getLinkageAttrName(),
                      builder.getI64IntegerAttr(static_cast<int64_t>(linkage)));
  if (addrSpace != 0)
    result.addAttribute("addr_space", builder.getI32IntegerAttr(addrSpace));
  result.attributes.append(attrs.begin(), attrs.end());
  result.addRegion();
}

static void printGlobalOp(OpAsmPrinter &p, GlobalOp op) {
  p << op.getOperationName() << ' ' << stringifyLinkage(op.linkage()) << ' ';
  if (op.constant())
    p << "constant ";
  p.printSymbolName(op.sym_name());
  p << '(';
  if (auto value = op.getValueOrNull())
    p.printAttribute(value);
  p << ')';
  p.printOptionalAttrDict(op.getAttrs(),
                          {SymbolTable::getSymbolAttrName(), "type", "constant",
                           "value", getLinkageAttrName()});

  // Print the trailing type unless it's a string global.
  if (op.getValueOrNull().dyn_cast_or_null<StringAttr>())
    return;
  p << " : " << op.type();

  Region &initializer = op.getInitializerRegion();
  if (!initializer.empty())
    p.printRegion(initializer, /*printEntryBlockArgs=*/false);
}

//===----------------------------------------------------------------------===//
// Verifier for LLVM::DialectCastOp.
//===----------------------------------------------------------------------===//

/// Checks if `llvmType` is dialect cast-compatible with `index` type. Does not
/// report the error, the user is expected to produce an appropriate message.
// TODO: make the size depend on data layout rather than on the conversion
// pass option, and pull that information here.
static LogicalResult verifyCastWithIndex(Type llvmType) {
  return success(llvmType.isa<IntegerType>());
}

/// Checks if `llvmType` is dialect cast-compatible with built-in `type` and
/// reports errors to the location of `op`. `isElement` indicates whether the
/// verification is performed for types that are element types inside a
/// container; we don't want casts from X to X at the top level, but c1<X> to
/// c2<X> may be fine.
static LogicalResult verifyCast(DialectCastOp op, Type llvmType, Type type,
                                bool isElement = false) {
  // Equal element types are directly compatible.
  if (isElement && llvmType == type)
    return success();

  // Index is compatible with any integer.
  if (type.isIndex()) {
    if (succeeded(verifyCastWithIndex(llvmType)))
      return success();

    return op.emitOpError("invalid cast between index and non-integer type");
  }

  if (type.isa<IntegerType>()) {
    auto llvmIntegerType = llvmType.dyn_cast<IntegerType>();
    if (!llvmIntegerType)
      return op->emitOpError("invalid cast between integer and non-integer");
    if (llvmIntegerType.getWidth() != type.getIntOrFloatBitWidth())
      return op.emitOpError("invalid cast changing integer width");
    return success();
  }

  // Vectors are compatible if they are 1D non-scalable, and their element types
  // are compatible. nD vectors are compatible with (n-1)D arrays containing 1D
  // vector.
  if (auto vectorType = type.dyn_cast<VectorType>()) {
    if (vectorType == llvmType && !isElement)
      return op.emitOpError("vector types should not be casted");

    if (vectorType.getRank() == 1) {
      auto llvmVectorType = llvmType.dyn_cast<VectorType>();
      if (!llvmVectorType || llvmVectorType.getRank() != 1)
        return op.emitOpError("invalid cast for vector types");

      return verifyCast(op, llvmVectorType.getElementType(),
                        vectorType.getElementType(), /*isElement=*/true);
    }

    auto arrayType = llvmType.dyn_cast<LLVM::LLVMArrayType>();
    if (!arrayType ||
        arrayType.getNumElements() != vectorType.getShape().front())
      return op.emitOpError("invalid cast for vector, expected array");
    return verifyCast(op, arrayType.getElementType(),
                      VectorType::get(vectorType.getShape().drop_front(),
                                      vectorType.getElementType()),
                      /*isElement=*/true);
  }

  if (auto memrefType = type.dyn_cast<MemRefType>()) {
    // Bare pointer convention: statically-shaped memref is compatible with an
    // LLVM pointer to the element type.
    if (auto ptrType = llvmType.dyn_cast<LLVMPointerType>()) {
      if (!memrefType.hasStaticShape())
        return op->emitOpError(
            "unexpected bare pointer for dynamically shaped memref");
      if (memrefType.getMemorySpace() != ptrType.getAddressSpace())
        return op->emitError("invalid conversion between memref and pointer in "
                             "different memory spaces");

      return verifyCast(op, ptrType.getElementType(),
                        memrefType.getElementType(), /*isElement=*/true);
    }

    // Otherwise, memrefs are convertible to a descriptor, which is a structure
    // type.
    auto structType = llvmType.dyn_cast<LLVMStructType>();
    if (!structType)
      return op->emitOpError("invalid cast between a memref and a type other "
                             "than pointer or memref descriptor");

    unsigned expectedNumElements = memrefType.getRank() == 0 ? 3 : 5;
    if (structType.getBody().size() != expectedNumElements) {
      return op->emitOpError() << "expected memref descriptor with "
                               << expectedNumElements << " elements";
    }

    // The first two elements are pointers to the element type.
    auto allocatedPtr = structType.getBody()[0].dyn_cast<LLVMPointerType>();
    if (!allocatedPtr ||
        allocatedPtr.getAddressSpace() != memrefType.getMemorySpace())
      return op->emitOpError("expected first element of a memref descriptor to "
                             "be a pointer in the address space of the memref");
    if (failed(verifyCast(op, allocatedPtr.getElementType(),
                          memrefType.getElementType(), /*isElement=*/true)))
      return failure();

    auto alignedPtr = structType.getBody()[1].dyn_cast<LLVMPointerType>();
    if (!alignedPtr ||
        alignedPtr.getAddressSpace() != memrefType.getMemorySpace())
      return op->emitOpError(
          "expected second element of a memref descriptor to "
          "be a pointer in the address space of the memref");
    if (failed(verifyCast(op, alignedPtr.getElementType(),
                          memrefType.getElementType(), /*isElement=*/true)))
      return failure();

    // The second element (offset) is an equivalent of index.
    if (failed(verifyCastWithIndex(structType.getBody()[2])))
      return op->emitOpError("expected third element of a memref descriptor to "
                             "be index-compatible integers");

    // 0D memrefs don't have sizes/strides.
    if (memrefType.getRank() == 0)
      return success();

    // Sizes and strides are rank-sized arrays of `index` equivalents.
    auto sizes = structType.getBody()[3].dyn_cast<LLVMArrayType>();
    if (!sizes || failed(verifyCastWithIndex(sizes.getElementType())) ||
        sizes.getNumElements() != memrefType.getRank())
      return op->emitOpError(
          "expected fourth element of a memref descriptor "
          "to be an array of <rank> index-compatible integers");

    auto strides = structType.getBody()[4].dyn_cast<LLVMArrayType>();
    if (!strides || failed(verifyCastWithIndex(strides.getElementType())) ||
        strides.getNumElements() != memrefType.getRank())
      return op->emitOpError(
          "expected fifth element of a memref descriptor "
          "to be an array of <rank> index-compatible integers");

    return success();
  }

  // Unranked memrefs are compatible with their descriptors.
  if (auto unrankedMemrefType = type.dyn_cast<UnrankedMemRefType>()) {
    auto structType = llvmType.dyn_cast<LLVMStructType>();
    if (!structType || structType.getBody().size() != 2)
      return op->emitOpError(
          "expected descriptor to be a struct with two elements");

    if (failed(verifyCastWithIndex(structType.getBody()[0])))
      return op->emitOpError("expected first element of a memref descriptor to "
                             "be an index-compatible integer");

    auto ptrType = structType.getBody()[1].dyn_cast<LLVMPointerType>();
    auto ptrElementType =
        ptrType ? ptrType.getElementType().dyn_cast<IntegerType>() : nullptr;
    if (!ptrElementType || ptrElementType.getWidth() != 8)
      return op->emitOpError("expected second element of a memref descriptor "
                             "to be an !llvm.ptr<i8>");

    return success();
  }

  // Complex types are compatible with the two-element structs.
  if (auto complexType = type.dyn_cast<ComplexType>()) {
    auto structType = llvmType.dyn_cast<LLVMStructType>();
    if (!structType || structType.getBody().size() != 2 ||
        structType.getBody()[0] != structType.getBody()[1] ||
        structType.getBody()[0] != complexType.getElementType())
      return op->emitOpError("expected 'complex' to map to two-element struct "
                             "with identical element types");
    return success();
  }

  // Everything else is not supported.
  return op->emitError("unsupported cast");
}

static LogicalResult verify(DialectCastOp op) {
  if (isCompatibleType(op.getType()))
    return verifyCast(op, op.getType(), op.in().getType());

  if (!isCompatibleType(op.in().getType()))
    return op->emitOpError("expected one LLVM type and one built-in type");

  return verifyCast(op, op.in().getType(), op.getType());
}

// Parses one of the keywords provided in the list `keywords` and returns the
// position of the parsed keyword in the list. If none of the keywords from the
// list is parsed, returns -1.
static int parseOptionalKeywordAlternative(OpAsmParser &parser,
                                           ArrayRef<StringRef> keywords) {
  for (auto en : llvm::enumerate(keywords)) {
    if (succeeded(parser.parseOptionalKeyword(en.value())))
      return en.index();
  }
  return -1;
}

namespace {
template <typename Ty> struct EnumTraits {};

#define REGISTER_ENUM_TYPE(Ty)                                                 \
  template <> struct EnumTraits<Ty> {                                          \
    static StringRef stringify(Ty value) { return stringify##Ty(value); }      \
    static unsigned getMaxEnumVal() { return getMaxEnumValFor##Ty(); }         \
  }

REGISTER_ENUM_TYPE(Linkage);
} // end namespace

template <typename EnumTy>
static ParseResult parseOptionalLLVMKeyword(OpAsmParser &parser,
                                            OperationState &result,
                                            StringRef name) {
  SmallVector<StringRef, 10> names;
  for (unsigned i = 0, e = getMaxEnumValForLinkage(); i <= e; ++i)
    names.push_back(EnumTraits<EnumTy>::stringify(static_cast<EnumTy>(i)));

  int index = parseOptionalKeywordAlternative(parser, names);
  if (index == -1)
    return failure();
  result.addAttribute(name, parser.getBuilder().getI64IntegerAttr(index));
  return success();
}

// operation ::= `llvm.mlir.global` linkage? `constant`? `@` identifier
//               `(` attribute? `)` attribute-list? (`:` type)? region?
//
// The type can be omitted for string attributes, in which case it will be
// inferred from the value of the string as [strlen(value) x i8].
static ParseResult parseGlobalOp(OpAsmParser &parser, OperationState &result) {
  if (failed(parseOptionalLLVMKeyword<Linkage>(parser, result,
                                               getLinkageAttrName())))
    result.addAttribute(getLinkageAttrName(),
                        parser.getBuilder().getI64IntegerAttr(
                            static_cast<int64_t>(LLVM::Linkage::External)));

  if (succeeded(parser.parseOptionalKeyword("constant")))
    result.addAttribute("constant", parser.getBuilder().getUnitAttr());

  StringAttr name;
  if (parser.parseSymbolName(name, SymbolTable::getSymbolAttrName(),
                             result.attributes) ||
      parser.parseLParen())
    return failure();

  Attribute value;
  if (parser.parseOptionalRParen()) {
    if (parser.parseAttribute(value, "value", result.attributes) ||
        parser.parseRParen())
      return failure();
  }

  SmallVector<Type, 1> types;
  if (parser.parseOptionalAttrDict(result.attributes) ||
      parser.parseOptionalColonTypeList(types))
    return failure();

  if (types.size() > 1)
    return parser.emitError(parser.getNameLoc(), "expected zero or one type");

  Region &initRegion = *result.addRegion();
  if (types.empty()) {
    if (auto strAttr = value.dyn_cast_or_null<StringAttr>()) {
      MLIRContext *context = parser.getBuilder().getContext();
      auto arrayType = LLVM::LLVMArrayType::get(IntegerType::get(context, 8),
                                                strAttr.getValue().size());
      types.push_back(arrayType);
    } else {
      return parser.emitError(parser.getNameLoc(),
                              "type can only be omitted for string globals");
    }
  } else {
    OptionalParseResult parseResult =
        parser.parseOptionalRegion(initRegion, /*arguments=*/{},
                                   /*argTypes=*/{});
    if (parseResult.hasValue() && failed(*parseResult))
      return failure();
  }

  result.addAttribute("type", TypeAttr::get(types[0]));
  return success();
}

static LogicalResult verify(GlobalOp op) {
  if (!LLVMPointerType::isValidElementType(op.getType()))
    return op.emitOpError(
        "expects type to be a valid element type for an LLVM pointer");
  if (op->getParentOp() && !satisfiesLLVMModule(op->getParentOp()))
    return op.emitOpError("must appear at the module level");

  if (auto strAttr = op.getValueOrNull().dyn_cast_or_null<StringAttr>()) {
    auto type = op.getType().dyn_cast<LLVMArrayType>();
    IntegerType elementType =
        type ? type.getElementType().dyn_cast<IntegerType>() : nullptr;
    if (!elementType || elementType.getWidth() != 8 ||
        type.getNumElements() != strAttr.getValue().size())
      return op.emitOpError(
          "requires an i8 array type of the length equal to that of the string "
          "attribute");
  }

  if (Block *b = op.getInitializerBlock()) {
    ReturnOp ret = cast<ReturnOp>(b->getTerminator());
    if (ret.operand_type_begin() == ret.operand_type_end())
      return op.emitOpError("initializer region cannot return void");
    if (*ret.operand_type_begin() != op.getType())
      return op.emitOpError("initializer region type ")
             << *ret.operand_type_begin() << " does not match global type "
             << op.getType();

    if (op.getValueOrNull())
      return op.emitOpError("cannot have both initializer value and region");
  }
  return success();
}

//===----------------------------------------------------------------------===//
// Printing/parsing for LLVM::ShuffleVectorOp.
//===----------------------------------------------------------------------===//
// Expects vector to be of wrapped LLVM vector type and position to be of
// wrapped LLVM i32 type.
void LLVM::ShuffleVectorOp::build(OpBuilder &b, OperationState &result,
                                  Value v1, Value v2, ArrayAttr mask,
                                  ArrayRef<NamedAttribute> attrs) {
  auto containerType = v1.getType();
  auto vType = LLVM::getFixedVectorType(
      LLVM::getVectorElementType(containerType), mask.size());
  build(b, result, vType, v1, v2, mask);
  result.addAttributes(attrs);
}

static void printShuffleVectorOp(OpAsmPrinter &p, ShuffleVectorOp &op) {
  p << op.getOperationName() << ' ' << op.v1() << ", " << op.v2() << " "
    << op.mask();
  p.printOptionalAttrDict(op.getAttrs(), {"mask"});
  p << " : " << op.v1().getType() << ", " << op.v2().getType();
}

// <operation> ::= `llvm.shufflevector` ssa-use `, ` ssa-use
//                 `[` integer-literal (`,` integer-literal)* `]`
//                 attribute-dict? `:` type
static ParseResult parseShuffleVectorOp(OpAsmParser &parser,
                                        OperationState &result) {
  llvm::SMLoc loc;
  OpAsmParser::OperandType v1, v2;
  ArrayAttr maskAttr;
  Type typeV1, typeV2;
  if (parser.getCurrentLocation(&loc) || parser.parseOperand(v1) ||
      parser.parseComma() || parser.parseOperand(v2) ||
      parser.parseAttribute(maskAttr, "mask", result.attributes) ||
      parser.parseOptionalAttrDict(result.attributes) ||
      parser.parseColonType(typeV1) || parser.parseComma() ||
      parser.parseType(typeV2) ||
      parser.resolveOperand(v1, typeV1, result.operands) ||
      parser.resolveOperand(v2, typeV2, result.operands))
    return failure();
  if (!LLVM::isCompatibleVectorType(typeV1))
    return parser.emitError(
        loc, "expected LLVM IR dialect vector type for operand #1");
  auto vType = LLVM::getFixedVectorType(LLVM::getVectorElementType(typeV1),
                                        maskAttr.size());
  result.addTypes(vType);
  return success();
}

//===----------------------------------------------------------------------===//
// Implementations for LLVM::LLVMFuncOp.
//===----------------------------------------------------------------------===//

// Add the entry block to the function.
Block *LLVMFuncOp::addEntryBlock() {
  assert(empty() && "function already has an entry block");
  assert(!isVarArg() && "unimplemented: non-external variadic functions");

  auto *entry = new Block;
  push_back(entry);

  LLVMFunctionType type = getType();
  for (unsigned i = 0, e = type.getNumParams(); i < e; ++i)
    entry->addArgument(type.getParamType(i));
  return entry;
}

void LLVMFuncOp::build(OpBuilder &builder, OperationState &result,
                       StringRef name, Type type, LLVM::Linkage linkage,
                       ArrayRef<NamedAttribute> attrs,
                       ArrayRef<DictionaryAttr> argAttrs) {
  result.addRegion();
  result.addAttribute(SymbolTable::getSymbolAttrName(),
                      builder.getStringAttr(name));
  result.addAttribute("type", TypeAttr::get(type));
  result.addAttribute(getLinkageAttrName(),
                      builder.getI64IntegerAttr(static_cast<int64_t>(linkage)));
  result.attributes.append(attrs.begin(), attrs.end());
  if (argAttrs.empty())
    return;

  unsigned numInputs = type.cast<LLVMFunctionType>().getNumParams();
  assert(numInputs == argAttrs.size() &&
         "expected as many argument attribute lists as arguments");
  SmallString<8> argAttrName;
  for (unsigned i = 0; i < numInputs; ++i)
    if (DictionaryAttr argDict = argAttrs[i])
      result.addAttribute(getArgAttrName(i, argAttrName), argDict);
}

// Builds an LLVM function type from the given lists of input and output types.
// Returns a null type if any of the types provided are non-LLVM types, or if
// there is more than one output type.
static Type buildLLVMFunctionType(OpAsmParser &parser, llvm::SMLoc loc,
                                  ArrayRef<Type> inputs, ArrayRef<Type> outputs,
                                  impl::VariadicFlag variadicFlag) {
  Builder &b = parser.getBuilder();
  if (outputs.size() > 1) {
    parser.emitError(loc, "failed to construct function type: expected zero or "
                          "one function result");
    return {};
  }

  // Convert inputs to LLVM types, exit early on error.
  SmallVector<Type, 4> llvmInputs;
  for (auto t : inputs) {
    if (!isCompatibleType(t)) {
      parser.emitError(loc, "failed to construct function type: expected LLVM "
                            "type for function arguments");
      return {};
    }
    llvmInputs.push_back(t);
  }

  // No output is denoted as "void" in LLVM type system.
  Type llvmOutput =
      outputs.empty() ? LLVMVoidType::get(b.getContext()) : outputs.front();
  if (!isCompatibleType(llvmOutput)) {
    parser.emitError(loc, "failed to construct function type: expected LLVM "
                          "type for function results")
        << llvmOutput;
    return {};
  }
  return LLVMFunctionType::get(llvmOutput, llvmInputs,
                               variadicFlag.isVariadic());
}

// Parses an LLVM function.
//
// operation ::= `llvm.func` linkage? function-signature function-attributes?
//               function-body
//
static ParseResult parseLLVMFuncOp(OpAsmParser &parser,
                                   OperationState &result) {
  // Default to external linkage if no keyword is provided.
  if (failed(parseOptionalLLVMKeyword<Linkage>(parser, result,
                                               getLinkageAttrName())))
    result.addAttribute(getLinkageAttrName(),
                        parser.getBuilder().getI64IntegerAttr(
                            static_cast<int64_t>(LLVM::Linkage::External)));

  StringAttr nameAttr;
  SmallVector<OpAsmParser::OperandType, 8> entryArgs;
  SmallVector<NamedAttrList, 1> argAttrs;
  SmallVector<NamedAttrList, 1> resultAttrs;
  SmallVector<Type, 8> argTypes;
  SmallVector<Type, 4> resultTypes;
  bool isVariadic;

  auto signatureLocation = parser.getCurrentLocation();
  if (parser.parseSymbolName(nameAttr, SymbolTable::getSymbolAttrName(),
                             result.attributes) ||
      impl::parseFunctionSignature(parser, /*allowVariadic=*/true, entryArgs,
                                   argTypes, argAttrs, isVariadic, resultTypes,
                                   resultAttrs))
    return failure();

  auto type =
      buildLLVMFunctionType(parser, signatureLocation, argTypes, resultTypes,
                            impl::VariadicFlag(isVariadic));
  if (!type)
    return failure();
  result.addAttribute(impl::getTypeAttrName(), TypeAttr::get(type));

  if (failed(parser.parseOptionalAttrDictWithKeyword(result.attributes)))
    return failure();
  impl::addArgAndResultAttrs(parser.getBuilder(), result, argAttrs,
                             resultAttrs);

  auto *body = result.addRegion();
  OptionalParseResult parseResult = parser.parseOptionalRegion(
      *body, entryArgs, entryArgs.empty() ? ArrayRef<Type>() : argTypes);
  return failure(parseResult.hasValue() && failed(*parseResult));
}

// Print the LLVMFuncOp. Collects argument and result types and passes them to
// helper functions. Drops "void" result since it cannot be parsed back. Skips
// the external linkage since it is the default value.
static void printLLVMFuncOp(OpAsmPrinter &p, LLVMFuncOp op) {
  p << op.getOperationName() << ' ';
  if (op.linkage() != LLVM::Linkage::External)
    p << stringifyLinkage(op.linkage()) << ' ';
  p.printSymbolName(op.getName());

  LLVMFunctionType fnType = op.getType();
  SmallVector<Type, 8> argTypes;
  SmallVector<Type, 1> resTypes;
  argTypes.reserve(fnType.getNumParams());
  for (unsigned i = 0, e = fnType.getNumParams(); i < e; ++i)
    argTypes.push_back(fnType.getParamType(i));

  Type returnType = fnType.getReturnType();
  if (!returnType.isa<LLVMVoidType>())
    resTypes.push_back(returnType);

  impl::printFunctionSignature(p, op, argTypes, op.isVarArg(), resTypes);
  impl::printFunctionAttributes(p, op, argTypes.size(), resTypes.size(),
                                {getLinkageAttrName()});

  // Print the body if this is not an external function.
  Region &body = op.body();
  if (!body.empty())
    p.printRegion(body, /*printEntryBlockArgs=*/false,
                  /*printBlockTerminators=*/true);
}

// Hook for OpTrait::FunctionLike, called after verifying that the 'type'
// attribute is present.  This can check for preconditions of the
// getNumArguments hook not failing.
LogicalResult LLVMFuncOp::verifyType() {
  auto llvmType = getTypeAttr().getValue().dyn_cast_or_null<LLVMFunctionType>();
  if (!llvmType)
    return emitOpError("requires '" + getTypeAttrName() +
                       "' attribute of wrapped LLVM function type");

  return success();
}

// Hook for OpTrait::FunctionLike, returns the number of function arguments.
// Depends on the type attribute being correct as checked by verifyType
unsigned LLVMFuncOp::getNumFuncArguments() { return getType().getNumParams(); }

// Hook for OpTrait::FunctionLike, returns the number of function results.
// Depends on the type attribute being correct as checked by verifyType
unsigned LLVMFuncOp::getNumFuncResults() {
  // We model LLVM functions that return void as having zero results,
  // and all others as having one result.
  // If we modeled a void return as one result, then it would be possible to
  // attach an MLIR result attribute to it, and it isn't clear what semantics we
  // would assign to that.
  if (getType().getReturnType().isa<LLVMVoidType>())
    return 0;
  return 1;
}

// Verifies LLVM- and implementation-specific properties of the LLVM func Op:
// - functions don't have 'common' linkage
// - external functions have 'external' or 'extern_weak' linkage;
// - vararg is (currently) only supported for external functions;
// - entry block arguments are of LLVM types and match the function signature.
static LogicalResult verify(LLVMFuncOp op) {
  if (op.linkage() == LLVM::Linkage::Common)
    return op.emitOpError()
           << "functions cannot have '"
           << stringifyLinkage(LLVM::Linkage::Common) << "' linkage";

  if (op.isExternal()) {
    if (op.linkage() != LLVM::Linkage::External &&
        op.linkage() != LLVM::Linkage::ExternWeak)
      return op.emitOpError()
             << "external functions must have '"
             << stringifyLinkage(LLVM::Linkage::External) << "' or '"
             << stringifyLinkage(LLVM::Linkage::ExternWeak) << "' linkage";
    return success();
  }

  if (op.isVarArg())
    return op.emitOpError("only external functions can be variadic");

  unsigned numArguments = op.getType().getNumParams();
  Block &entryBlock = op.front();
  for (unsigned i = 0; i < numArguments; ++i) {
    Type argType = entryBlock.getArgument(i).getType();
    if (!isCompatibleType(argType))
      return op.emitOpError("entry block argument #")
             << i << " is not of LLVM type";
    if (op.getType().getParamType(i) != argType)
      return op.emitOpError("the type of entry block argument #")
             << i << " does not match the function signature";
  }

  return success();
}

//===----------------------------------------------------------------------===//
// Verification for LLVM::ConstantOp.
//===----------------------------------------------------------------------===//

static LogicalResult verify(LLVM::ConstantOp op) {
  if (!(op.value().isa<IntegerAttr>() || op.value().isa<FloatAttr>() ||
        op.value().isa<ElementsAttr>() || op.value().isa<StringAttr>()))
    return op.emitOpError()
           << "only supports integer, float, string or elements attributes";
  return success();
}

//===----------------------------------------------------------------------===//
// Utility functions for parsing atomic ops
//===----------------------------------------------------------------------===//

// Helper function to parse a keyword into the specified attribute named by
// `attrName`. The keyword must match one of the string values defined by the
// AtomicBinOp enum. The resulting I64 attribute is added to the `result`
// state.
static ParseResult parseAtomicBinOp(OpAsmParser &parser, OperationState &result,
                                    StringRef attrName) {
  llvm::SMLoc loc;
  StringRef keyword;
  if (parser.getCurrentLocation(&loc) || parser.parseKeyword(&keyword))
    return failure();

  // Replace the keyword `keyword` with an integer attribute.
  auto kind = symbolizeAtomicBinOp(keyword);
  if (!kind) {
    return parser.emitError(loc)
           << "'" << keyword << "' is an incorrect value of the '" << attrName
           << "' attribute";
  }

  auto value = static_cast<int64_t>(kind.getValue());
  auto attr = parser.getBuilder().getI64IntegerAttr(value);
  result.addAttribute(attrName, attr);

  return success();
}

// Helper function to parse a keyword into the specified attribute named by
// `attrName`. The keyword must match one of the string values defined by the
// AtomicOrdering enum. The resulting I64 attribute is added to the `result`
// state.
static ParseResult parseAtomicOrdering(OpAsmParser &parser,
                                       OperationState &result,
                                       StringRef attrName) {
  llvm::SMLoc loc;
  StringRef ordering;
  if (parser.getCurrentLocation(&loc) || parser.parseKeyword(&ordering))
    return failure();

  // Replace the keyword `ordering` with an integer attribute.
  auto kind = symbolizeAtomicOrdering(ordering);
  if (!kind) {
    return parser.emitError(loc)
           << "'" << ordering << "' is an incorrect value of the '" << attrName
           << "' attribute";
  }

  auto value = static_cast<int64_t>(kind.getValue());
  auto attr = parser.getBuilder().getI64IntegerAttr(value);
  result.addAttribute(attrName, attr);

  return success();
}

//===----------------------------------------------------------------------===//
// Printer, parser and verifier for LLVM::AtomicRMWOp.
//===----------------------------------------------------------------------===//

static void printAtomicRMWOp(OpAsmPrinter &p, AtomicRMWOp &op) {
  p << op.getOperationName() << ' ' << stringifyAtomicBinOp(op.bin_op()) << ' '
    << op.ptr() << ", " << op.val() << ' '
    << stringifyAtomicOrdering(op.ordering()) << ' ';
  p.printOptionalAttrDict(op.getAttrs(), {"bin_op", "ordering"});
  p << " : " << op.res().getType();
}

// <operation> ::= `llvm.atomicrmw` keyword ssa-use `,` ssa-use keyword
//                 attribute-dict? `:` type
static ParseResult parseAtomicRMWOp(OpAsmParser &parser,
                                    OperationState &result) {
  Type type;
  OpAsmParser::OperandType ptr, val;
  if (parseAtomicBinOp(parser, result, "bin_op") || parser.parseOperand(ptr) ||
      parser.parseComma() || parser.parseOperand(val) ||
      parseAtomicOrdering(parser, result, "ordering") ||
      parser.parseOptionalAttrDict(result.attributes) ||
      parser.parseColonType(type) ||
      parser.resolveOperand(ptr, LLVM::LLVMPointerType::get(type),
                            result.operands) ||
      parser.resolveOperand(val, type, result.operands))
    return failure();

  result.addTypes(type);
  return success();
}

static LogicalResult verify(AtomicRMWOp op) {
  auto ptrType = op.ptr().getType().cast<LLVM::LLVMPointerType>();
  auto valType = op.val().getType();
  if (valType != ptrType.getElementType())
    return op.emitOpError("expected LLVM IR element type for operand #0 to "
                          "match type for operand #1");
  auto resType = op.res().getType();
  if (resType != valType)
    return op.emitOpError(
        "expected LLVM IR result type to match type for operand #1");
  if (op.bin_op() == AtomicBinOp::fadd || op.bin_op() == AtomicBinOp::fsub) {
    if (!mlir::LLVM::isCompatibleFloatingPointType(valType))
      return op.emitOpError("expected LLVM IR floating point type");
  } else if (op.bin_op() == AtomicBinOp::xchg) {
    auto intType = valType.dyn_cast<IntegerType>();
    unsigned intBitWidth = intType ? intType.getWidth() : 0;
    if (intBitWidth != 8 && intBitWidth != 16 && intBitWidth != 32 &&
        intBitWidth != 64 && !valType.isa<BFloat16Type>() &&
        !valType.isa<Float16Type>() && !valType.isa<Float32Type>() &&
        !valType.isa<Float64Type>())
      return op.emitOpError("unexpected LLVM IR type for 'xchg' bin_op");
  } else {
    auto intType = valType.dyn_cast<IntegerType>();
    unsigned intBitWidth = intType ? intType.getWidth() : 0;
    if (intBitWidth != 8 && intBitWidth != 16 && intBitWidth != 32 &&
        intBitWidth != 64)
      return op.emitOpError("expected LLVM IR integer type");
  }
  return success();
}

//===----------------------------------------------------------------------===//
// Printer, parser and verifier for LLVM::AtomicCmpXchgOp.
//===----------------------------------------------------------------------===//

static void printAtomicCmpXchgOp(OpAsmPrinter &p, AtomicCmpXchgOp &op) {
  p << op.getOperationName() << ' ' << op.ptr() << ", " << op.cmp() << ", "
    << op.val() << ' ' << stringifyAtomicOrdering(op.success_ordering()) << ' '
    << stringifyAtomicOrdering(op.failure_ordering());
  p.printOptionalAttrDict(op.getAttrs(),
                          {"success_ordering", "failure_ordering"});
  p << " : " << op.val().getType();
}

// <operation> ::= `llvm.cmpxchg` ssa-use `,` ssa-use `,` ssa-use
//                 keyword keyword attribute-dict? `:` type
static ParseResult parseAtomicCmpXchgOp(OpAsmParser &parser,
                                        OperationState &result) {
  auto &builder = parser.getBuilder();
  Type type;
  OpAsmParser::OperandType ptr, cmp, val;
  if (parser.parseOperand(ptr) || parser.parseComma() ||
      parser.parseOperand(cmp) || parser.parseComma() ||
      parser.parseOperand(val) ||
      parseAtomicOrdering(parser, result, "success_ordering") ||
      parseAtomicOrdering(parser, result, "failure_ordering") ||
      parser.parseOptionalAttrDict(result.attributes) ||
      parser.parseColonType(type) ||
      parser.resolveOperand(ptr, LLVM::LLVMPointerType::get(type),
                            result.operands) ||
      parser.resolveOperand(cmp, type, result.operands) ||
      parser.resolveOperand(val, type, result.operands))
    return failure();

  auto boolType = IntegerType::get(builder.getContext(), 1);
  auto resultType =
      LLVMStructType::getLiteral(builder.getContext(), {type, boolType});
  result.addTypes(resultType);

  return success();
}

static LogicalResult verify(AtomicCmpXchgOp op) {
  auto ptrType = op.ptr().getType().cast<LLVM::LLVMPointerType>();
  if (!ptrType)
    return op.emitOpError("expected LLVM IR pointer type for operand #0");
  auto cmpType = op.cmp().getType();
  auto valType = op.val().getType();
  if (cmpType != ptrType.getElementType() || cmpType != valType)
    return op.emitOpError("expected LLVM IR element type for operand #0 to "
                          "match type for all other operands");
  auto intType = valType.dyn_cast<IntegerType>();
  unsigned intBitWidth = intType ? intType.getWidth() : 0;
  if (!valType.isa<LLVMPointerType>() && intBitWidth != 8 &&
      intBitWidth != 16 && intBitWidth != 32 && intBitWidth != 64 &&
      !valType.isa<BFloat16Type>() && !valType.isa<Float16Type>() &&
      !valType.isa<Float32Type>() && !valType.isa<Float64Type>())
    return op.emitOpError("unexpected LLVM IR type");
  if (op.success_ordering() < AtomicOrdering::monotonic ||
      op.failure_ordering() < AtomicOrdering::monotonic)
    return op.emitOpError("ordering must be at least 'monotonic'");
  if (op.failure_ordering() == AtomicOrdering::release ||
      op.failure_ordering() == AtomicOrdering::acq_rel)
    return op.emitOpError("failure ordering cannot be 'release' or 'acq_rel'");
  return success();
}

//===----------------------------------------------------------------------===//
// Printer, parser and verifier for LLVM::FenceOp.
//===----------------------------------------------------------------------===//

// <operation> ::= `llvm.fence` (`syncscope(`strAttr`)`)? keyword
// attribute-dict?
static ParseResult parseFenceOp(OpAsmParser &parser, OperationState &result) {
  StringAttr sScope;
  StringRef syncscopeKeyword = "syncscope";
  if (!failed(parser.parseOptionalKeyword(syncscopeKeyword))) {
    if (parser.parseLParen() ||
        parser.parseAttribute(sScope, syncscopeKeyword, result.attributes) ||
        parser.parseRParen())
      return failure();
  } else {
    result.addAttribute(syncscopeKeyword,
                        parser.getBuilder().getStringAttr(""));
  }
  if (parseAtomicOrdering(parser, result, "ordering") ||
      parser.parseOptionalAttrDict(result.attributes))
    return failure();
  return success();
}

static void printFenceOp(OpAsmPrinter &p, FenceOp &op) {
  StringRef syncscopeKeyword = "syncscope";
  p << op.getOperationName() << ' ';
  if (!op->getAttr(syncscopeKeyword).cast<StringAttr>().getValue().empty())
    p << "syncscope(" << op->getAttr(syncscopeKeyword) << ") ";
  p << stringifyAtomicOrdering(op.ordering());
}

static LogicalResult verify(FenceOp &op) {
  if (op.ordering() == AtomicOrdering::not_atomic ||
      op.ordering() == AtomicOrdering::unordered ||
      op.ordering() == AtomicOrdering::monotonic)
    return op.emitOpError("can be given only acquire, release, acq_rel, "
                          "and seq_cst orderings");
  return success();
}

//===----------------------------------------------------------------------===//
// LLVMDialect initialization, type parsing, and registration.
//===----------------------------------------------------------------------===//

void LLVMDialect::initialize() {
  addAttributes<FMFAttr>();

  // clang-format off
  addTypes<LLVMVoidType,
           LLVMPPCFP128Type,
           LLVMX86MMXType,
           LLVMTokenType,
           LLVMLabelType,
           LLVMMetadataType,
           LLVMFunctionType,
           LLVMPointerType,
           LLVMFixedVectorType,
           LLVMScalableVectorType,
           LLVMArrayType,
           LLVMStructType>();
  // clang-format on
  addOperations<
#define GET_OP_LIST
#include "mlir/Dialect/LLVMIR/LLVMOps.cpp.inc"
      >();

  // Support unknown operations because not all LLVM operations are registered.
  allowUnknownOperations();
}

#define GET_OP_CLASSES
#include "mlir/Dialect/LLVMIR/LLVMOps.cpp.inc"

/// Parse a type registered to this dialect.
Type LLVMDialect::parseType(DialectAsmParser &parser) const {
  return detail::parseType(parser);
}

/// Print a type registered to this dialect.
void LLVMDialect::printType(Type type, DialectAsmPrinter &os) const {
  return detail::printType(type, os);
}

LogicalResult LLVMDialect::verifyDataLayoutString(
    StringRef descr, llvm::function_ref<void(const Twine &)> reportError) {
  llvm::Expected<llvm::DataLayout> maybeDataLayout =
      llvm::DataLayout::parse(descr);
  if (maybeDataLayout)
    return success();

  std::string message;
  llvm::raw_string_ostream messageStream(message);
  llvm::logAllUnhandledErrors(maybeDataLayout.takeError(), messageStream);
  reportError("invalid data layout descriptor: " + messageStream.str());
  return failure();
}

/// Verify LLVM dialect attributes.
LogicalResult LLVMDialect::verifyOperationAttribute(Operation *op,
                                                    NamedAttribute attr) {
  // If the data layout attribute is present, it must use the LLVM data layout
  // syntax. Try parsing it and report errors in case of failure. Users of this
  // attribute may assume it is well-formed and can pass it to the (asserting)
  // llvm::DataLayout constructor.
  if (attr.first.strref() != LLVM::LLVMDialect::getDataLayoutAttrName())
    return success();
  if (auto stringAttr = attr.second.dyn_cast<StringAttr>())
    return verifyDataLayoutString(
        stringAttr.getValue(),
        [op](const Twine &message) { op->emitOpError() << message.str(); });

  return op->emitOpError() << "expected '"
                           << LLVM::LLVMDialect::getDataLayoutAttrName()
                           << "' to be a string attribute";
}

/// Verify LLVMIR function argument attributes.
LogicalResult LLVMDialect::verifyRegionArgAttribute(Operation *op,
                                                    unsigned regionIdx,
                                                    unsigned argIdx,
                                                    NamedAttribute argAttr) {
  // Check that llvm.noalias is a boolean attribute.
  if (argAttr.first == LLVMDialect::getNoAliasAttrName() &&
      !argAttr.second.isa<BoolAttr>())
    return op->emitError()
           << "llvm.noalias argument attribute of non boolean type";
  // Check that llvm.align is an integer attribute.
  if (argAttr.first == LLVMDialect::getAlignAttrName() &&
      !argAttr.second.isa<IntegerAttr>())
    return op->emitError()
           << "llvm.align argument attribute of non integer type";
  return success();
}

//===----------------------------------------------------------------------===//
// Utility functions.
//===----------------------------------------------------------------------===//

Value mlir::LLVM::createGlobalString(Location loc, OpBuilder &builder,
                                     StringRef name, StringRef value,
                                     LLVM::Linkage linkage) {
  assert(builder.getInsertionBlock() &&
         builder.getInsertionBlock()->getParentOp() &&
         "expected builder to point to a block constrained in an op");
  auto module =
      builder.getInsertionBlock()->getParentOp()->getParentOfType<ModuleOp>();
  assert(module && "builder points to an op outside of a module");

  // Create the global at the entry of the module.
  OpBuilder moduleBuilder(module.getBodyRegion(), builder.getListener());
  MLIRContext *ctx = builder.getContext();
  auto type = LLVM::LLVMArrayType::get(IntegerType::get(ctx, 8), value.size());
  auto global = moduleBuilder.create<LLVM::GlobalOp>(
      loc, type, /*isConstant=*/true, linkage, name,
      builder.getStringAttr(value));

  // Get the pointer to the first character in the global string.
  Value globalPtr = builder.create<LLVM::AddressOfOp>(loc, global);
  Value cst0 = builder.create<LLVM::ConstantOp>(
      loc, IntegerType::get(ctx, 64),
      builder.getIntegerAttr(builder.getIndexType(), 0));
  return builder.create<LLVM::GEPOp>(
      loc, LLVM::LLVMPointerType::get(IntegerType::get(ctx, 8)), globalPtr,
      ValueRange{cst0, cst0});
}

bool mlir::LLVM::satisfiesLLVMModule(Operation *op) {
  return op->hasTrait<OpTrait::SymbolTable>() &&
         op->hasTrait<OpTrait::IsIsolatedFromAbove>();
}

FMFAttr FMFAttr::get(FastmathFlags flags, MLIRContext *context) {
  return Base::get(context, static_cast<uint64_t>(flags));
}

FastmathFlags FMFAttr::getFlags() const {
  return static_cast<FastmathFlags>(getImpl()->value);
}

static constexpr const FastmathFlags FastmathFlagsList[] = {
    // clang-format off
    FastmathFlags::nnan,
    FastmathFlags::ninf,
    FastmathFlags::nsz,
    FastmathFlags::arcp,
    FastmathFlags::contract,
    FastmathFlags::afn,
    FastmathFlags::reassoc,
    FastmathFlags::fast,
    // clang-format on
};

void FMFAttr::print(DialectAsmPrinter &printer) const {
  printer << "fastmath<";
  auto flags = llvm::make_filter_range(FastmathFlagsList, [&](auto flag) {
    return bitEnumContains(this->getFlags(), flag);
  });
  llvm::interleaveComma(flags, printer,
                        [&](auto flag) { printer << stringifyEnum(flag); });
  printer << ">";
}

Attribute FMFAttr::parse(DialectAsmParser &parser) {
  if (failed(parser.parseLess()))
    return {};

  FastmathFlags flags = {};
  if (failed(parser.parseOptionalGreater())) {
    do {
      StringRef elemName;
      if (failed(parser.parseKeyword(&elemName)))
        return {};

      auto elem = symbolizeFastmathFlags(elemName);
      if (!elem) {
        parser.emitError(parser.getNameLoc(), "Unknown fastmath flag: ")
            << elemName;
        return {};
      }

      flags = flags | *elem;
    } while (succeeded(parser.parseOptionalComma()));

    if (failed(parser.parseGreater()))
      return {};
  }

  return FMFAttr::get(flags, parser.getBuilder().getContext());
}

Attribute LLVMDialect::parseAttribute(DialectAsmParser &parser,
                                      Type type) const {
  if (type) {
    parser.emitError(parser.getNameLoc(), "unexpected type");
    return {};
  }
  StringRef attrKind;
  if (parser.parseKeyword(&attrKind))
    return {};

  if (attrKind == "fastmath")
    return FMFAttr::parse(parser);

  parser.emitError(parser.getNameLoc(), "Unknown attrribute type: ")
      << attrKind;
  return {};
}

void LLVMDialect::printAttribute(Attribute attr, DialectAsmPrinter &os) const {
  if (auto fmf = attr.dyn_cast<FMFAttr>())
    fmf.print(os);
  else
    llvm_unreachable("Unknown attribute type");
}