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 : public FunctionPass<TestLoopPermutation> {
29   TestLoopPermutation() = default;
30   TestLoopPermutation(const TestLoopPermutation &pass){};
31 
32   void runOnFunction() override;
33 
34 private:
35   /// Permutation specifying loop i is mapped to permList[i] in
36   /// transformed nest (with i going from outermost to innermost).
37   ListOption<unsigned> permList{*this, "permutation-map",
38                                 llvm::cl::desc("Specify the loop permutation"),
39                                 llvm::cl::OneOrMore, llvm::cl::CommaSeparated};
40 };
41 
42 } // end anonymous namespace
43 
44 void TestLoopPermutation::runOnFunction() {
45   // Get the first maximal perfect nest.
46   SmallVector<AffineForOp, 6> nest;
47   for (auto &op : getFunction().front()) {
48     if (auto forOp = dyn_cast<AffineForOp>(op)) {
49       getPerfectlyNestedLoops(nest, forOp);
50       break;
51     }
52   }
53 
54   // Nothing to do.
55   if (nest.size() < 2)
56     return;
57 
58   SmallVector<unsigned, 4> permMap(permList.begin(), permList.end());
59   permuteLoops(nest, permMap);
60 }
61 
62 namespace mlir {
63 void registerTestLoopPermutationPass() {
64   PassRegistration<TestLoopPermutation>(
65       PASS_NAME, "Tests affine loop permutation utility");
66 }
67 } // namespace mlir
68