//===- Bufferize.cpp - Bufferization for func ops -------------------------===//
//
// 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 implements bufferization of func.func's and func.call's.
//
//===----------------------------------------------------------------------===//

#include "PassDetail.h"
#include "mlir/Dialect/Bufferization/IR/Bufferization.h"
#include "mlir/Dialect/Bufferization/Transforms/Bufferize.h"
#include "mlir/Dialect/Func/IR/FuncOps.h"
#include "mlir/Dialect/Func/Transforms/FuncConversions.h"
#include "mlir/Dialect/Func/Transforms/Passes.h"
#include "mlir/Dialect/MemRef/IR/MemRef.h"
#include "mlir/Transforms/DialectConversion.h"

using namespace mlir;
using namespace mlir::func;

namespace {
struct FuncBufferizePass : public FuncBufferizeBase<FuncBufferizePass> {
  using FuncBufferizeBase<FuncBufferizePass>::FuncBufferizeBase;
  void runOnOperation() override {
    auto module = getOperation();
    auto *context = &getContext();

    bufferization::BufferizeTypeConverter typeConverter;
    RewritePatternSet patterns(context);
    ConversionTarget target(*context);

    populateFunctionOpInterfaceTypeConversionPattern<FuncOp>(patterns,
                                                             typeConverter);
    target.addDynamicallyLegalOp<FuncOp>([&](FuncOp op) {
      return typeConverter.isSignatureLegal(op.getFunctionType()) &&
             typeConverter.isLegal(&op.getBody());
    });
    populateCallOpTypeConversionPattern(patterns, typeConverter);
    target.addDynamicallyLegalOp<CallOp>(
        [&](CallOp op) { return typeConverter.isLegal(op); });

    populateBranchOpInterfaceTypeConversionPattern(patterns, typeConverter);
    populateReturnOpTypeConversionPattern(patterns, typeConverter);
    target.addLegalOp<ModuleOp, bufferization::ToTensorOp,
                      bufferization::ToMemrefOp>();

    target.markUnknownOpDynamicallyLegal([&](Operation *op) {
      return isNotBranchOpInterfaceOrReturnLikeOp(op) ||
             isLegalForBranchOpInterfaceTypeConversionPattern(op,
                                                              typeConverter) ||
             isLegalForReturnOpTypeConversionPattern(op, typeConverter);
    });

    if (failed(applyFullConversion(module, target, std::move(patterns))))
      signalPassFailure();
  }
};
} // namespace

std::unique_ptr<Pass> mlir::func::createFuncBufferizePass() {
  return std::make_unique<FuncBufferizePass>();
}