mlir-hlo/lib/Dialect/mhlo/IR/lhlo_ops.cc

/* Copyright 2019 The TensorFlow Authors. All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==============================================================================*/

// This file defines the operations used in the LMHLO dialect.

#include "mlir-hlo/Dialect/mhlo/IR/lhlo_ops.h"

#include <assert.h>
#include <stddef.h>
#include <stdint.h>

#include "llvm/ADT/APFloat.h"
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/FormatVariadic.h"
#include "mlir-hlo/Dialect/mhlo/IR/lhlo_ops.h.inc"
#include "mlir/Dialect/StandardOps/IR/Ops.h"
#include "mlir/IR/Attributes.h"
#include "mlir/IR/Builders.h"
#include "mlir/IR/Dialect.h"
#include "mlir/IR/Location.h"
#include "mlir/IR/MLIRContext.h"
#include "mlir/IR/OpDefinition.h"
#include "mlir/IR/OpImplementation.h"
#include "mlir/IR/Operation.h"
#include "mlir/IR/OperationSupport.h"
#include "mlir/IR/PatternMatch.h"
#include "mlir/IR/StandardTypes.h"
#include "mlir/IR/TypeUtilities.h"
#include "mlir/IR/Types.h"
#include "mlir/IR/Value.h"

namespace mlir {
namespace lmhlo {

LmhloDialect::LmhloDialect(MLIRContext *context)
    : Dialect(getDialectNamespace(), context, TypeID::get<LmhloDialect>()) {
  addOperations<
#define GET_OP_LIST
#include "mlir-hlo/Dialect/mhlo/IR/lhlo_ops.cc.inc"
      >();
}

//===----------------------------------------------------------------------===//
// ConstOp.
//===----------------------------------------------------------------------===//

/// An lho.constant on an memref that is locally allocated and with no other
/// users (other than dealloc's) can be erased.
// TODO: This can be generalized to an arbitrary op by making use of memory
// effects (write memory effect).
struct EraseConstOp : public OpRewritePattern<ConstOp> {
  using OpRewritePattern<ConstOp>::OpRewritePattern;

  LogicalResult matchAndRewrite(ConstOp op,
                                PatternRewriter& rewriter) const override {
    Value memref = op.output();
    if (!memref.getDefiningOp<AllocOp>()) {
      return failure();
    }

    // Check that all uses of the memref are either DeallocOps or this op.
    for (Operation* user : memref.getUsers())
      if (user != op && !isa<DeallocOp>(user)) return failure();

    rewriter.eraseOp(op);
    return success();
  }
};

void ConstOp::getCanonicalizationPatterns(OwningRewritePatternList& results,
                                          MLIRContext* context) {
  results.insert<EraseConstOp>(context);
}

}  // namespace lmhlo
}  // namespace mlir

#define GET_OP_CLASSES
#include "mlir-hlo/Dialect/mhlo/IR/lhlo_ops.cc.inc"

namespace mlir {
namespace lmhlo {

// TODO(cheshire): Support folding, reuse code from hlo_ops.cc.

void FusionOp::build(OpBuilder &builder, OperationState &result,
                     ArrayRef<NamedAttribute> attributes) {
  result.addAttributes(attributes);
  Region *bodyRegion = result.addRegion();
  FusionOp::ensureTerminator(*bodyRegion, builder, result.location);
}

}  // namespace lmhlo
}  // namespace mlir