1 //===- Canonicalizer.cpp - Canonicalize MLIR operations -------------------===//
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 // This transformation pass converts operations into their canonical forms by
10 // folding constants, applying operation identity transformations etc.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "PassDetail.h"
15 #include "mlir/Pass/Pass.h"
16 #include "mlir/Transforms/GreedyPatternRewriteDriver.h"
17 #include "mlir/Transforms/Passes.h"
18 
19 using namespace mlir;
20 
21 namespace {
22 /// Canonicalize operations in nested regions.
23 struct Canonicalizer : public CanonicalizerBase<Canonicalizer> {
runOnOperation__anona5b21df90111::Canonicalizer24   void runOnOperation() override {
25     OwningRewritePatternList patterns;
26 
27     // TODO: Instead of adding all known patterns from the whole system lazily
28     // add and cache the canonicalization patterns for ops we see in practice
29     // when building the worklist.  For now, we just grab everything.
30     auto *context = &getContext();
31     for (auto *op : context->getRegisteredOperations())
32       op->getCanonicalizationPatterns(patterns, context);
33 
34     Operation *op = getOperation();
35     applyPatternsAndFoldGreedily(op->getRegions(), std::move(patterns));
36   }
37 };
38 } // end anonymous namespace
39 
40 /// Create a Canonicalizer pass.
createCanonicalizerPass()41 std::unique_ptr<Pass> mlir::createCanonicalizerPass() {
42   return std::make_unique<Canonicalizer>();
43 }
44