1 | //===- ShapeToShapeLowering.cpp - Prepare for lowering to Standard --------===// |
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-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | |
9 | #include "mlir/Dialect/Shape/Transforms/Passes.h" |
10 | |
11 | #include "mlir/Dialect/Arith/IR/Arith.h" |
12 | #include "mlir/Dialect/Func/IR/FuncOps.h" |
13 | #include "mlir/Dialect/Shape/IR/Shape.h" |
14 | #include "mlir/IR/Builders.h" |
15 | #include "mlir/IR/PatternMatch.h" |
16 | #include "mlir/Pass/Pass.h" |
17 | #include "mlir/Transforms/DialectConversion.h" |
18 | |
19 | namespace mlir { |
20 | #define GEN_PASS_DEF_SHAPETOSHAPELOWERING |
21 | #include "mlir/Dialect/Shape/Transforms/Passes.h.inc" |
22 | } // namespace mlir |
23 | |
24 | using namespace mlir; |
25 | using namespace mlir::shape; |
26 | |
27 | namespace { |
28 | /// Converts `shape.num_elements` to `shape.reduce`. |
29 | struct NumElementsOpConverter : public OpRewritePattern<NumElementsOp> { |
30 | public: |
31 | using OpRewritePattern::OpRewritePattern; |
32 | |
33 | LogicalResult matchAndRewrite(NumElementsOp op, |
34 | PatternRewriter &rewriter) const final; |
35 | }; |
36 | } // namespace |
37 | |
38 | LogicalResult |
39 | NumElementsOpConverter::matchAndRewrite(NumElementsOp op, |
40 | PatternRewriter &rewriter) const { |
41 | auto loc = op.getLoc(); |
42 | Type valueType = op.getResult().getType(); |
43 | Value init = op->getDialect() |
44 | ->materializeConstant(rewriter, rewriter.getIndexAttr(1), |
45 | valueType, loc) |
46 | ->getResult(0); |
47 | ReduceOp reduce = rewriter.create<ReduceOp>(loc, op.getShape(), init); |
48 | |
49 | // Generate reduce operator. |
50 | Block *body = reduce.getBody(); |
51 | OpBuilder b = OpBuilder::atBlockEnd(block: body); |
52 | Value product = b.create<MulOp>(loc, valueType, body->getArgument(1), |
53 | body->getArgument(2)); |
54 | b.create<shape::YieldOp>(loc, product); |
55 | |
56 | rewriter.replaceOp(op, reduce.getResult()); |
57 | return success(); |
58 | } |
59 | |
60 | namespace { |
61 | struct ShapeToShapeLowering |
62 | : public impl::ShapeToShapeLoweringBase<ShapeToShapeLowering> { |
63 | void runOnOperation() override; |
64 | }; |
65 | } // namespace |
66 | |
67 | void ShapeToShapeLowering::runOnOperation() { |
68 | MLIRContext &ctx = getContext(); |
69 | |
70 | RewritePatternSet patterns(&ctx); |
71 | populateShapeRewritePatterns(patterns); |
72 | |
73 | ConversionTarget target(getContext()); |
74 | target.addLegalDialect<arith::ArithDialect, ShapeDialect>(); |
75 | target.addIllegalOp<NumElementsOp>(); |
76 | if (failed(mlir::applyPartialConversion(getOperation(), target, |
77 | std::move(patterns)))) |
78 | signalPassFailure(); |
79 | } |
80 | |
81 | void mlir::populateShapeRewritePatterns(RewritePatternSet &patterns) { |
82 | patterns.add<NumElementsOpConverter>(arg: patterns.getContext()); |
83 | } |
84 | |
85 | std::unique_ptr<Pass> mlir::createShapeToShapeLowering() { |
86 | return std::make_unique<ShapeToShapeLowering>(); |
87 | } |
88 | |