50 lines · cpp
1//===- ConcatOpPatterns.cpp - Patterns related to tensor.concat lowering --===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "mlir/Dialect/Tensor/IR/Tensor.h"10#include "mlir/Dialect/Tensor/Transforms/Transforms.h"11#include "mlir/IR/PatternMatch.h"12 13using namespace mlir;14using namespace mlir::tensor;15 16namespace {17 18/// Decompose `tensor.concat` into `tensor.empty` and a chain of slice inserts.19///20/// %concat = tensor.concat dim(1) %0, %1 :21/// (tensor<2x3xf32>, tensor<2x4xf32>) -> tensor<2x7xf32>22///23/// Becomes24///25/// %empty = tensor.empty() : tensor<2x7xf32>26/// %insert0 = tensor.insert_slice %0 into %empty[0, 0][2, 3][1, 1]27/// %concat = tensor.insert_slice %1 into %insert0[0, 3][2, 4][1, 1]28struct DecomposeTensorConcatOp : public OpRewritePattern<ConcatOp> {29 using OpRewritePattern<ConcatOp>::OpRewritePattern;30 31 LogicalResult matchAndRewrite(ConcatOp concatOp,32 PatternRewriter &rewriter) const override {33 FailureOr<SmallVector<Value>> decomposed =34 concatOp.decomposeOperation(rewriter);35 if (failed(decomposed)) {36 return rewriter.notifyMatchFailure(37 concatOp, "failed to get the decomposed insert slices");38 }39 rewriter.replaceOp(concatOp, decomposed.value()[0]);40 return success();41 }42};43 44} // namespace45 46void mlir::tensor::populateDecomposeTensorConcatPatterns(47 RewritePatternSet &patterns) {48 patterns.add<DecomposeTensorConcatOp>(patterns.getContext());49}50