| //===- ToyCombine.td - Pattern Match Optimizations for Toy -*- tablegen -*-===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // Defines language-specific pattern match optimizations for Toy using |
| // Declarative Rewrite Rules (DRR) specified using TableGen records. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef TOY_COMBINE |
| #define TOY_COMBINE |
| |
| include "toy/Ops.td" |
| |
| /// Note: The DRR definition used for defining patterns is shown below: |
| /// |
| /// class Pattern< |
| /// dag sourcePattern, list<dag> resultPatterns, |
| /// list<dag> additionalConstraints = [], |
| /// dag benefitsAdded = (addBenefit 0) |
| /// >; |
| |
| //===----------------------------------------------------------------------===// |
| // Basic Pattern-Match and Rewrite |
| //===----------------------------------------------------------------------===// |
| |
| // Reshape(Reshape(x)) = Reshape(x) |
| def ReshapeReshapeOptPattern : Pat<(ReshapeOp(ReshapeOp $arg)), |
| (ReshapeOp $arg)>; |
| |
| //===----------------------------------------------------------------------===// |
| // Pattern-Match and Rewrite using Native Code Call |
| //===----------------------------------------------------------------------===// |
| |
| // Native Code Calls may be used for more complex transformations using inline |
| // C++ and C++ helper functions. |
| |
| // Reshape(Constant(x)) = x' |
| def ReshapeConstant : |
| NativeCodeCall<"$0.reshape(($1.getType()).cast<ShapedType>())">; |
| def FoldConstantReshapeOptPattern : Pat< |
| (ReshapeOp:$res (ConstantOp $arg)), |
| (ConstantOp (ReshapeConstant $arg, $res))>; |
| |
| //===----------------------------------------------------------------------===// |
| // Pattern-Match and Rewrite with Constraints |
| //===----------------------------------------------------------------------===// |
| |
| // DRR allows for constraint checking when the transformation is conditional |
| // on operand properties. |
| |
| // Reshape(x) = x, where input and output shapes are identical |
| def TypesAreIdentical : Constraint<CPred<"$0.getType() == $1.getType()">>; |
| def RedundantReshapeOptPattern : Pat< |
| (ReshapeOp:$res $arg), (replaceWithValue $arg), |
| [(TypesAreIdentical $res, $arg)]>; |
| |
| #endif // TOY_COMBINE |
