xref: /llvm-project/mlir/test/lib/Dialect/Affine/TestAffineDataCopy.cpp (revision 09dfc5713d7e2342bea4c8447d1ed76c85eb8225)
1 //===- TestAffineDataCopy.cpp - Test affine data copy utility -------------===//
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 affine data copy utility functions and
10 // options.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "mlir/Dialect/Affine/Analysis/Utils.h"
15 #include "mlir/Dialect/Affine/IR/AffineOps.h"
16 #include "mlir/Dialect/Affine/LoopUtils.h"
17 #include "mlir/Dialect/Func/IR/FuncOps.h"
18 #include "mlir/Dialect/MemRef/IR/MemRef.h"
19 #include "mlir/Pass/Pass.h"
20 #include "mlir/Transforms/GreedyPatternRewriteDriver.h"
21 #include "mlir/Transforms/Passes.h"
22 
23 #define PASS_NAME "test-affine-data-copy"
24 
25 using namespace mlir;
26 using namespace mlir::affine;
27 
28 namespace {
29 
30 struct TestAffineDataCopy
31     : public PassWrapper<TestAffineDataCopy, OperationPass<func::FuncOp>> {
32   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(TestAffineDataCopy)
33 
34   StringRef getArgument() const final { return PASS_NAME; }
35   StringRef getDescription() const final {
36     return "Tests affine data copy utility functions.";
37   }
38   TestAffineDataCopy() = default;
39   TestAffineDataCopy(const TestAffineDataCopy &pass) : PassWrapper(pass){};
40 
41   void getDependentDialects(DialectRegistry &registry) const override {
42     registry.insert<memref::MemRefDialect>();
43   }
44   void runOnOperation() override;
45 
46 private:
47   Option<bool> clMemRefFilter{
48       *this, "memref-filter",
49       llvm::cl::desc(
50           "Enable memref filter testing in affine data copy optimization"),
51       llvm::cl::init(false)};
52   Option<bool> clTestGenerateCopyForMemRegion{
53       *this, "for-memref-region",
54       llvm::cl::desc("Test copy generation for a single memref region"),
55       llvm::cl::init(false)};
56 };
57 
58 } // namespace
59 
60 void TestAffineDataCopy::runOnOperation() {
61   // Gather all AffineForOps by loop depth.
62   std::vector<SmallVector<AffineForOp, 2>> depthToLoops;
63   gatherLoops(getOperation(), depthToLoops);
64   if (depthToLoops.empty())
65     return;
66 
67   // Only support tests with a single loop nest and a single innermost loop
68   // for now.
69   unsigned innermostLoopIdx = depthToLoops.size() - 1;
70   if (depthToLoops[0].size() != 1 || depthToLoops[innermostLoopIdx].size() != 1)
71     return;
72 
73   auto loopNest = depthToLoops[0][0];
74   auto innermostLoop = depthToLoops[innermostLoopIdx][0];
75   AffineLoadOp load;
76   if (clMemRefFilter || clTestGenerateCopyForMemRegion) {
77     // Gather MemRef filter. For simplicity, we use the first loaded memref
78     // found in the innermost loop.
79     for (auto &op : *innermostLoop.getBody()) {
80       if (auto ld = dyn_cast<AffineLoadOp>(op)) {
81         load = ld;
82         break;
83       }
84     }
85   }
86   if (!load)
87     return;
88 
89   AffineCopyOptions copyOptions = {/*generateDma=*/false,
90                                    /*slowMemorySpace=*/0,
91                                    /*fastMemorySpace=*/0,
92                                    /*tagMemorySpace=*/0,
93                                    /*fastMemCapacityBytes=*/32 * 1024 * 1024UL};
94   DenseSet<Operation *> copyNests;
95   if (clMemRefFilter) {
96     if (failed(affineDataCopyGenerate(loopNest, copyOptions, load.getMemRef(),
97                                       copyNests)))
98       return;
99   } else if (clTestGenerateCopyForMemRegion) {
100     CopyGenerateResult result;
101     MemRefRegion region(loopNest.getLoc());
102     if (failed(region.compute(load, /*loopDepth=*/0)))
103       return;
104     if (failed(generateCopyForMemRegion(region, loopNest, copyOptions, result)))
105       return;
106   }
107 
108   // Promote any single iteration loops in the copy nests and simplify
109   // load/stores.
110   SmallVector<Operation *, 4> copyOps;
111   for (Operation *nest : copyNests) {
112     // With a post order walk, the erasure of loops does not affect
113     // continuation of the walk or the collection of load/store ops.
114     nest->walk([&](Operation *op) {
115       if (auto forOp = dyn_cast<AffineForOp>(op))
116         (void)promoteIfSingleIteration(forOp);
117       else if (auto loadOp = dyn_cast<AffineLoadOp>(op))
118         copyOps.push_back(loadOp);
119       else if (auto storeOp = dyn_cast<AffineStoreOp>(op))
120         copyOps.push_back(storeOp);
121     });
122   }
123 
124   // Promoting single iteration loops could lead to simplification of
125   // generated load's/store's, and the latter could anyway also be
126   // canonicalized.
127   RewritePatternSet patterns(&getContext());
128   for (Operation *op : copyOps) {
129     patterns.clear();
130     if (isa<AffineLoadOp>(op)) {
131       AffineLoadOp::getCanonicalizationPatterns(patterns, &getContext());
132     } else {
133       assert(isa<AffineStoreOp>(op) && "expected affine store op");
134       AffineStoreOp::getCanonicalizationPatterns(patterns, &getContext());
135     }
136   }
137   GreedyRewriteConfig config;
138   config.strictMode = GreedyRewriteStrictness::ExistingAndNewOps;
139   (void)applyOpPatternsGreedily(copyOps, std::move(patterns), config);
140 }
141 
142 namespace mlir {
143 void registerTestAffineDataCopyPass() {
144   PassRegistration<TestAffineDataCopy>();
145 }
146 } // namespace mlir
147