| //===- SimplifyAffineExpr.cpp - MLIR Affine Structures Class-----*- C++ -*-===// |
| // |
| // Copyright 2019 The MLIR Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| // ============================================================================= |
| // |
| // This file implements a pass to simplify affine expressions. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "mlir/Analysis/AffineStructures.h" |
| #include "mlir/IR/MLFunction.h" |
| #include "mlir/IR/StmtVisitor.h" |
| #include "mlir/Pass.h" |
| #include "mlir/Transforms/Passes.h" |
| |
| #define DEBUG_TYPE "simplify-affine-structure" |
| |
| using namespace mlir; |
| using llvm::report_fatal_error; |
| |
| namespace { |
| |
| /// Simplifies all affine expressions appearing in the operation statements of |
| /// the MLFunction. This is mainly to test the simplifyAffineExpr method. |
| // TODO(someone): Gradually, extend this to all affine map references found in |
| // ML functions and CFG functions. |
| struct SimplifyAffineStructures : public FunctionPass, |
| StmtWalker<SimplifyAffineStructures> { |
| explicit SimplifyAffineStructures() {} |
| |
| PassResult runOnMLFunction(MLFunction *f) override; |
| // Does nothing on CFG functions for now. No reusable walkers/visitors exist |
| // for this yet? TODO(someone). |
| PassResult runOnCFGFunction(CFGFunction *f) override { return success(); } |
| |
| void visitIfStmt(IfStmt *ifStmt); |
| void visitOperationStmt(OperationStmt *opStmt); |
| |
| static char passID; |
| }; |
| |
| } // end anonymous namespace |
| |
| char SimplifyAffineStructures::passID = 0; |
| |
| FunctionPass *mlir::createSimplifyAffineStructuresPass() { |
| return new SimplifyAffineStructures(); |
| } |
| |
| static IntegerSet simplifyIntegerSet(IntegerSet set) { |
| FlatAffineConstraints fac(set); |
| if (fac.isEmpty()) |
| return IntegerSet::getEmptySet(set.getNumDims(), set.getNumSymbols(), |
| set.getContext()); |
| return set; |
| } |
| |
| void SimplifyAffineStructures::visitIfStmt(IfStmt *ifStmt) { |
| auto set = ifStmt->getCondition().getIntegerSet(); |
| ifStmt->setIntegerSet(simplifyIntegerSet(set)); |
| } |
| |
| void SimplifyAffineStructures::visitOperationStmt(OperationStmt *opStmt) { |
| for (auto attr : opStmt->getAttrs()) { |
| if (auto mapAttr = attr.second.dyn_cast<AffineMapAttr>()) { |
| MutableAffineMap mMap(mapAttr.getValue()); |
| mMap.simplify(); |
| auto map = mMap.getAffineMap(); |
| opStmt->setAttr(attr.first, AffineMapAttr::get(map)); |
| } |
| } |
| } |
| |
| PassResult SimplifyAffineStructures::runOnMLFunction(MLFunction *f) { |
| walk(f); |
| return success(); |
| } |
| |
| static PassRegistration<SimplifyAffineStructures> |
| pass("simplify-affine-structures", "Simplify affine expressions"); |