llvm-project/mlir/lib/Dialect/Linalg/Transforms/SwapExtractSliceWithFillPat...

42 lines
1.7 KiB
C++

//===- SwapExtractSliceWithFillPatterns.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
//
//===----------------------------------------------------------------------===//
#include "mlir/Dialect/Linalg/Transforms/Transforms.h"
#include "mlir/IR/PatternMatch.h"
using namespace mlir;
using namespace mlir::linalg;
/// Swaps tensor.extract_slice(linalg.fill(%cst, %init)) into linalg.fill(%cst,
/// tensor.extract_slice(%init)) when the linalg.fill op have no other users.
/// This helps to reduce the fill footprint.
struct SwapExtractSliceOfFill final
: public OpRewritePattern<tensor::ExtractSliceOp> {
using OpRewritePattern::OpRewritePattern;
LogicalResult matchAndRewrite(tensor::ExtractSliceOp extractOp,
PatternRewriter &rewriter) const override {
auto fillOp = extractOp.getSource().getDefiningOp<FillOp>();
if (!fillOp || !fillOp->hasOneUse())
return failure();
auto newExtractOp = rewriter.create<tensor::ExtractSliceOp>(
extractOp.getLoc(), extractOp.getType(), fillOp.getOutputs()[0],
extractOp.getMixedOffsets(), extractOp.getMixedSizes(),
extractOp.getMixedStrides());
rewriter.replaceOpWithNewOp<FillOp>(extractOp, fillOp.getInputs(),
ValueRange{newExtractOp.getResult()});
return success();
}
};
void mlir::linalg::populateSwapExtractSliceWithFillPatterns(
RewritePatternSet &patterns) {
patterns.add<SwapExtractSliceOfFill>(patterns.getContext());
}