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/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, FunctionPass> {
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){};
36 
37   void runOnFunction() 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 } // end anonymous namespace
48 
49 void TestLoopPermutation::runOnFunction() {
50   // Get the first maximal perfect nest.
51   SmallVector<AffineForOp, 6> nest;
52   for (auto &op : getFunction().front()) {
53     if (auto forOp = dyn_cast<AffineForOp>(op)) {
54       getPerfectlyNestedLoops(nest, forOp);
55       break;
56     }
57   }
58 
59   // Nothing to do.
60   if (nest.size() < 2)
61     return;
62 
63   SmallVector<unsigned, 4> permMap(permList.begin(), permList.end());
64   permuteLoops(nest, permMap);
65 }
66 
67 namespace mlir {
68 void registerTestLoopPermutationPass() {
69   PassRegistration<TestLoopPermutation>();
70 }
71 } // namespace mlir
72