1 //===- TestLoopPermutation.cpp - Test affine loop permutation -------------===//
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 file implements a pass to test the affine for op permutation utility.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "mlir/Dialect/Affine/Analysis/Utils.h"
14 #include "mlir/Dialect/Affine/IR/AffineOps.h"
15 #include "mlir/Pass/Pass.h"
16 #include "mlir/Transforms/LoopUtils.h"
17 #include "mlir/Transforms/Passes.h"
18 
19 #define PASS_NAME "test-loop-permutation"
20 
21 using namespace mlir;
22 
23 static llvm::cl::OptionCategory clOptionsCategory(PASS_NAME " options");
24 
25 namespace {
26 
27 /// This pass applies the permutation on the first maximal perfect nest.
28 struct TestLoopPermutation
29     : public PassWrapper<TestLoopPermutation, OperationPass<FuncOp>> {
30   StringRef getArgument() const final { return PASS_NAME; }
31   StringRef getDescription() const final {
32     return "Tests affine loop permutation utility";
33   }
34   TestLoopPermutation() = default;
35   TestLoopPermutation(const TestLoopPermutation &pass) : PassWrapper(pass){};
36 
37   void runOnOperation() override;
38 
39 private:
40   /// Permutation specifying loop i is mapped to permList[i] in
41   /// transformed nest (with i going from outermost to innermost).
42   ListOption<unsigned> permList{*this, "permutation-map",
43                                 llvm::cl::desc("Specify the loop permutation"),
44                                 llvm::cl::OneOrMore, llvm::cl::CommaSeparated};
45 };
46 
47 } // namespace
48 
49 void TestLoopPermutation::runOnOperation() {
50 
51   SmallVector<unsigned, 4> permMap(permList.begin(), permList.end());
52 
53   SmallVector<AffineForOp, 2> forOps;
54   getOperation().walk([&](AffineForOp forOp) { forOps.push_back(forOp); });
55 
56   for (auto forOp : forOps) {
57     SmallVector<AffineForOp, 6> nest;
58     // Get the maximal perfect nest.
59     getPerfectlyNestedLoops(nest, forOp);
60     // Permute if the nest's size is consistent with the specified
61     // permutation.
62     if (nest.size() >= 2 && nest.size() == permMap.size()) {
63       permuteLoops(nest, permMap);
64     }
65   }
66 }
67 
68 namespace mlir {
69 void registerTestLoopPermutationPass() {
70   PassRegistration<TestLoopPermutation>();
71 }
72 } // namespace mlir
73