//===-- FIRDialect.cpp ----------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// Coding style: https://mlir.llvm.org/getting_started/DeveloperGuide/
//
//===----------------------------------------------------------------------===//

#include "flang/Optimizer/Dialect/FIRDialect.h"
#include "flang/Optimizer/Dialect/CUF/Attributes/CUFAttr.h"
#include "flang/Optimizer/Dialect/FIRAttr.h"
#include "flang/Optimizer/Dialect/FIROps.h"
#include "flang/Optimizer/Dialect/FIRType.h"
#include "mlir/Dialect/Arith/IR/Arith.h"
#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
#include "mlir/Target/LLVMIR/ModuleTranslation.h"
#include "mlir/Transforms/InliningUtils.h"

#include "flang/Optimizer/Dialect/FIRDialect.cpp.inc"

using namespace fir;

namespace {
/// This class defines the interface for handling inlining of FIR calls.
struct FIRInlinerInterface : public mlir::DialectInlinerInterface {
  using DialectInlinerInterface::DialectInlinerInterface;

  bool isLegalToInline(mlir::Operation *call, mlir::Operation *callable,
                       bool wouldBeCloned) const final {
    return fir::canLegallyInline(call, callable, wouldBeCloned);
  }

  /// This hook checks to see if the operation `op` is legal to inline into the
  /// given region `reg`.
  bool isLegalToInline(mlir::Operation *op, mlir::Region *reg,
                       bool wouldBeCloned, mlir::IRMapping &map) const final {
    return fir::canLegallyInline(op, reg, wouldBeCloned, map);
  }

  /// This hook is called when a terminator operation has been inlined.
  /// We handle the return (a Fortran FUNCTION) by replacing the values
  /// previously returned by the call operation with the operands of the
  /// return.
  void handleTerminator(mlir::Operation *op,
                        mlir::ValueRange valuesToRepl) const final {
    auto returnOp = llvm::cast<mlir::func::ReturnOp>(op);
    assert(returnOp.getNumOperands() == valuesToRepl.size());
    for (const auto &it : llvm::enumerate(returnOp.getOperands()))
      valuesToRepl[it.index()].replaceAllUsesWith(it.value());
  }

  mlir::Operation *materializeCallConversion(mlir::OpBuilder &builder,
                                             mlir::Value input,
                                             mlir::Type resultType,
                                             mlir::Location loc) const final {
    return fir::ConvertOp::create(builder, loc, resultType, input);
  }
};
} // namespace

void fir::FIROpsDialect::initialize() {
  registerTypes();
  registerAttributes();
  addOperations<
#define GET_OP_LIST
#include "flang/Optimizer/Dialect/FIROps.cpp.inc"
      >();
  registerOpExternalInterfaces();
}

mlir::Operation *
fir::FIROpsDialect::materializeConstant(mlir::OpBuilder &builder,
                                        mlir::Attribute value, mlir::Type type,
                                        mlir::Location loc) {
  if (mlir::isa<mlir::IntegerAttr>(value) && mlir::isa<mlir::IntegerType>(type))
    return mlir::arith::ConstantOp::materialize(builder, value, type, loc);
  return nullptr;
}

// Register the FIRInlinerInterface to FIROpsDialect
void fir::addFIRInlinerExtension(mlir::DialectRegistry &registry) {
  registry.addExtension(
      +[](mlir::MLIRContext *ctx, fir::FIROpsDialect *dialect) {
        dialect->addInterface<FIRInlinerInterface>();
      });
}

// We do not provide LLVMTranslationDialectInterface implementation
// for FIR dialect, since at the point of translation to LLVM IR
// there should not be any FIR operations (the CodeGen converts
// them to LLVMIR dialect operations).
// Here we register the default implementation of
// LLVMTranslationDialectInterface that will drop all FIR dialect
// attributes - this helps to avoid warnings about unhandled attributes.
// We can provide our own implementation of the interface,
// when more sophisticated translation is required.
void fir::addFIRToLLVMIRExtension(mlir::DialectRegistry &registry) {
  registry.addExtension(
      +[](mlir::MLIRContext *ctx, fir::FIROpsDialect *dialect) {
        dialect->addInterface<mlir::LLVMTranslationDialectInterface>();
      });
}

mlir::Type fir::FIROpsDialect::parseType(mlir::DialectAsmParser &parser) const {
  return parseFirType(const_cast<FIROpsDialect *>(this), parser);
}

void fir::FIROpsDialect::printType(mlir::Type ty,
                                   mlir::DialectAsmPrinter &p) const {
  return printFirType(const_cast<FIROpsDialect *>(this), ty, p);
}

mlir::Attribute
fir::FIROpsDialect::parseAttribute(mlir::DialectAsmParser &parser,
                                   mlir::Type type) const {
  return parseFirAttribute(const_cast<FIROpsDialect *>(this), parser, type);
}

void fir::FIROpsDialect::printAttribute(mlir::Attribute attr,
                                        mlir::DialectAsmPrinter &p) const {
  printFirAttribute(const_cast<FIROpsDialect *>(this), attr, p);
}