Uday Bondhugula | cf4f4c4 | 2018-09-12 10:21:23 -0700 | [diff] [blame^] | 1 | //===- LoopAnalysis.h - loop analysis methods -------------------*- C++ -*-===// |
| 2 | // |
| 3 | // Copyright 2019 The MLIR Authors. |
| 4 | // |
| 5 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | // you may not use this file except in compliance with the License. |
| 7 | // You may obtain a copy of the License at |
| 8 | // |
| 9 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | // |
| 11 | // Unless required by applicable law or agreed to in writing, software |
| 12 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | // See the License for the specific language governing permissions and |
| 15 | // limitations under the License. |
| 16 | // ============================================================================= |
| 17 | // |
| 18 | // This header file defines prototypes for methods to analyze loops. |
| 19 | // |
| 20 | //===----------------------------------------------------------------------===// |
| 21 | |
| 22 | #ifndef MLIR_ANALYSIS_LOOP_ANALYSIS_H |
| 23 | #define MLIR_ANALYSIS_LOOP_ANALYSIS_H |
| 24 | |
| 25 | #include "llvm/ADT/Optional.h" |
| 26 | |
| 27 | namespace mlir { |
| 28 | |
| 29 | class AffineExpr; |
| 30 | class ForStmt; |
| 31 | |
| 32 | /// Returns the trip count of the loop as an affine expression if the latter is |
| 33 | /// expressible as an affine expression, and nullptr otherwise. The trip count |
| 34 | /// expression is simplified before returning. |
| 35 | AffineExpr *getTripCount(const ForStmt &forStmt); |
| 36 | |
| 37 | /// Returns the trip count of the loop if it's a constant, None otherwise. This |
| 38 | /// uses affine expression analysis and is able to determine constant trip count |
| 39 | /// in non-trivial cases. |
| 40 | llvm::Optional<uint64_t> getConstantTripCount(const ForStmt &forStmt); |
| 41 | |
| 42 | /// Returns the greatest known integral divisor of the trip count. Affine |
| 43 | /// expression analysis is used (indirectly through getTripCount), and |
| 44 | /// this method is thus able to determine non-trivial divisors. |
| 45 | uint64_t getLargestDivisorOfTripCount(const ForStmt &forStmt); |
| 46 | |
| 47 | } // end namespace mlir |
| 48 | |
| 49 | #endif // MLIR_ANALYSIS_LOOP_ANALYSIS_H |