1 //===- Tiling.cpp - Implementation of linalg Tiling -----------------------===//
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 the linalg dialect Tiling pass.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "PassDetail.h"
14 #include "mlir/Dialect/Affine/EDSC/Intrinsics.h"
15 #include "mlir/Dialect/Linalg/EDSC/FoldedIntrinsics.h"
16 #include "mlir/Dialect/Linalg/IR/LinalgTypes.h"
17 #include "mlir/Dialect/Linalg/Passes.h"
18 #include "mlir/Dialect/Linalg/Transforms/Transforms.h"
19 #include "mlir/Dialect/Linalg/Utils/Utils.h"
20 #include "mlir/Dialect/MemRef/EDSC/Intrinsics.h"
21 #include "mlir/Dialect/MemRef/IR/MemRef.h"
22 #include "mlir/Dialect/SCF/EDSC/Builders.h"
23 #include "mlir/Dialect/StandardOps/EDSC/Intrinsics.h"
24 #include "mlir/Dialect/Tensor/IR/Tensor.h"
25 #include "mlir/IR/AffineExpr.h"
26 #include "mlir/IR/AffineMap.h"
27 #include "mlir/Transforms/FoldUtils.h"
28 #include "mlir/Transforms/GreedyPatternRewriteDriver.h"
29 
30 #include "llvm/Support/CommandLine.h"
31 
32 using namespace mlir;
33 using namespace mlir::edsc;
34 using namespace mlir::edsc::intrinsics;
35 using namespace mlir::linalg;
36 using namespace mlir::scf;
37 
38 #define DEBUG_TYPE "linalg-tiling"
39 
40 static bool isZero(Value v) {
41   if (auto cst = v.getDefiningOp<ConstantIndexOp>())
42     return cst.getValue() == 0;
43   return false;
44 }
45 
46 using LoopIndexToRangeIndexMap = DenseMap<int, int>;
47 
48 // Creates a number of ranges equal to the number of non-zero in `tileSizes`.
49 // One for each loop of the LinalgOp that is tiled. The `tileSizes` argument has
50 // one entry per surrounding loop. It uses zero as the convention that a
51 // particular loop is not tiled. This convention simplifies implementations by
52 // avoiding affine map manipulations.
53 // The returned ranges correspond to the loop ranges, in the proper order, that
54 // are tiled and for which new loops will be created. Also the function returns
55 // a map from loop indices of the LinalgOp to the corresponding non-empty range
56 // indices of newly created loops.
57 static std::tuple<SmallVector<Range, 4>, LoopIndexToRangeIndexMap>
58 makeTiledLoopRanges(OpBuilder &b, Location loc, AffineMap map,
59                     ValueRange allShapeSizes, ValueRange allTileSizes) {
60   assert(allTileSizes.size() == map.getNumResults());
61   // Apply `map` to get shape sizes in loop order.
62   auto shapeSizes = applyMapToValues(b, loc, map, allShapeSizes);
63   SmallVector<Value, 4> tileSizes(allTileSizes.begin(), allTileSizes.end());
64 
65   // Traverse the tile sizes, which are in loop order, erase zeros everywhere.
66   LoopIndexToRangeIndexMap loopIndexToRangeIndex;
67   for (int idx = 0, e = tileSizes.size(), zerosCount = 0; idx < e; ++idx) {
68     if (isZero(tileSizes[idx - zerosCount])) {
69       shapeSizes.erase(shapeSizes.begin() + idx - zerosCount);
70       tileSizes.erase(tileSizes.begin() + idx - zerosCount);
71       ++zerosCount;
72       continue;
73     }
74     loopIndexToRangeIndex[idx] = idx - zerosCount;
75   }
76 
77   // Create a new range with the applied tile sizes.
78   SmallVector<Range, 4> res;
79   for (unsigned idx = 0, e = tileSizes.size(); idx < e; ++idx)
80     res.push_back(
81         Range{std_constant_index(0), shapeSizes[idx], tileSizes[idx]});
82   return std::make_tuple(res, loopIndexToRangeIndex);
83 }
84 
85 // IndexedGenericOp explicitly uses induction variables in the loop body. The
86 // values of the indices that are used in the loop body for any given access of
87 // input/output memref before `subview` op was applied should be invariant with
88 // respect to tiling.
89 //
90 // Therefore, if the operation is tiled, we have to transform the indices
91 // accordingly, i.e. offset them by the values of the corresponding induction
92 // variables that are captured implicitly in the body of the op.
93 //
94 // Example. `linalg.indexed_generic` before tiling:
95 //
96 // #id_2d = (i, j) -> (i, j)
97 // #pointwise_2d_trait = {
98 //   indexing_maps = [#id_2d, #id_2d],
99 //   iterator_types = ["parallel", "parallel"],
100 //   n_views = [1, 1]
101 // }
102 // linalg.indexed_generic #pointwise_2d_trait %operand, %result {
103 //   ^bb0(%i: index, %j: index, %operand_in: f32, %result_in: f32):
104 //     <some operations that use %i, %j>
105 // }: memref<50x100xf32>, memref<50x100xf32>
106 //
107 // After tiling pass with tiles sizes 10 and 25:
108 //
109 // #strided = (i, j)[s0, s1, s2] -> (i * s1 + s0 + j * s2)
110 //
111 // %c1 = constant 1 : index
112 // %c0 = constant 0 : index
113 // %c25 = constant 25 : index
114 // %c10 = constant 10 : index
115 // operand_dim_0 = dim %operand, 0 : memref<50x100xf32>
116 // operand_dim_1 = dim %operand, 1 : memref<50x100xf32>
117 // scf.for %k = %c0 to operand_dim_0 step %c10 {
118 //   scf.for %l = %c0 to operand_dim_1 step %c25 {
119 //     %4 = memref.subview %operand[%k, %l][%c10, %c25][%c1, %c1]
120 //       : memref<50x100xf32> to memref<?x?xf32, #strided>
121 //     %5 = memref.subview %result[%k, %l][%c10, %c25][%c1, %c1]
122 //       : memref<50x100xf32> to memref<?x?xf32, #strided>
123 //     linalg.indexed_generic pointwise_2d_trait %4, %5 {
124 //     ^bb0(%i: index, %j: index, %operand_in: f32, %result_in: f32):
125 //       // Indices `k` and `l` are implicitly captured in the body.
126 //       %transformed_i = addi %i, %k : index // index `i` is offset by %k
127 //       %transformed_j = addi %j, %l : index // index `j` is offset by %l
128 //       // Every use of %i, %j is replaced with %transformed_i, %transformed_j
129 //       <some operations that use %transformed_i, %transformed_j>
130 //     }: memref<?x?xf32, #strided>, memref<?x?xf32, #strided>
131 //   }
132 // }
133 //
134 // TODO: Investigate whether mixing implicit and explicit indices
135 // does not lead to losing information.
136 static void transformIndexedGenericOpIndices(
137     OpBuilder &b, LinalgOp op, SmallVectorImpl<Value> &ivs,
138     const LoopIndexToRangeIndexMap &loopIndexToRangeIndex) {
139   auto indexedGenericOp = dyn_cast<IndexedGenericOp>(op.getOperation());
140   if (!indexedGenericOp)
141     return;
142 
143   // `linalg.indexed_generic` comes in two flavours. One has a region with a
144   // single block that defines the loop body. The other has a `fun` attribute
145   // that refers to an existing function symbol. The `fun` function call will be
146   // inserted in the loop body in that case.
147   //
148   // TODO: Add support for `linalg.indexed_generic` with `fun` attribute.
149   auto &region = indexedGenericOp.region();
150   if (region.empty()) {
151     indexedGenericOp.emitOpError("expected a region");
152     return;
153   }
154   auto &block = region.front();
155 
156   OpBuilder::InsertionGuard g(b);
157   b.setInsertionPointToStart(&block);
158   for (unsigned i = 0; i < indexedGenericOp.getNumLoops(); ++i) {
159     auto rangeIndex = loopIndexToRangeIndex.find(i);
160     if (rangeIndex == loopIndexToRangeIndex.end())
161       continue;
162     Value oldIndex = block.getArgument(i);
163     // Offset the index argument `i` by the value of the corresponding induction
164     // variable and replace all uses of the previous value.
165     Value newIndex = b.create<AddIOp>(indexedGenericOp.getLoc(), oldIndex,
166                                       ivs[rangeIndex->second]);
167     for (auto &use : oldIndex.getUses()) {
168       if (use.getOwner() == newIndex.getDefiningOp())
169         continue;
170       use.set(newIndex);
171     }
172   }
173 }
174 
175 // All indices returned by IndexOp should be invariant with respect to tiling.
176 // Therefore, if an operation is tiled, we have to transform the indices
177 // accordingly, i.e. offset them by the values of the corresponding induction
178 // variables that are captured implicitly in the body of the op.
179 //
180 // Example. `linalg.generic` before tiling:
181 //
182 // #id_2d = (i, j) -> (i, j)
183 // #pointwise_2d_trait = {
184 //   indexing_maps = [#id_2d, #id_2d],
185 //   iterator_types = ["parallel", "parallel"]
186 // }
187 // linalg.generic #pointwise_2d_trait %operand, %result {
188 //   ^bb0(%operand_in: f32, %result_in: f32):
189 //     %i = linalg.index 0 : index
190 //     %j = linalg.index 1 : index
191 //     <some operations that use %i, %j>
192 // }: memref<50x100xf32>, memref<50x100xf32>
193 //
194 // After tiling pass with tiles sizes 10 and 25:
195 //
196 // #strided = (i, j)[s0, s1, s2] -> (i * s1 + s0 + j * s2)
197 //
198 // %c1 = constant 1 : index
199 // %c0 = constant 0 : index
200 // %c25 = constant 25 : index
201 // %c10 = constant 10 : index
202 // operand_dim_0 = dim %operand, 0 : memref<50x100xf32>
203 // operand_dim_1 = dim %operand, 1 : memref<50x100xf32>
204 // scf.for %k = %c0 to operand_dim_0 step %c10 {
205 //   scf.for %l = %c0 to operand_dim_1 step %c25 {
206 //     %4 = std.subview %operand[%k, %l][%c10, %c25][%c1, %c1]
207 //       : memref<50x100xf32> to memref<?x?xf32, #strided>
208 //     %5 = std.subview %result[%k, %l][%c10, %c25][%c1, %c1]
209 //       : memref<50x100xf32> to memref<?x?xf32, #strided>
210 //     linalg.generic pointwise_2d_trait %4, %5 {
211 //     ^bb0(%operand_in: f32, %result_in: f32):
212 //       %i = linalg.index 0 : index
213 //       %j = linalg.index 1 : index
214 //       // Indices `k` and `l` are implicitly captured in the body.
215 //       %transformed_i = addi %i, %k : index // index `i` is offset by %k
216 //       %transformed_j = addi %j, %l : index // index `j` is offset by %l
217 //       // Every use of %i, %j is replaced with %transformed_i, %transformed_j
218 //       <some operations that use %transformed_i, %transformed_j>
219 //     }: memref<?x?xf32, #strided>, memref<?x?xf32, #strided>
220 //   }
221 // }
222 //
223 // TODO: Investigate whether mixing implicit and explicit indices
224 // does not lead to losing information.
225 static void
226 transformIndexOps(OpBuilder &b, LinalgOp op, SmallVectorImpl<Value> &ivs,
227                   const LoopIndexToRangeIndexMap &loopIndexToRangeIndex) {
228   // Skip operations that have no region attached.
229   if (op->getNumRegions() == 0)
230     return;
231   assert(op->getNumRegions() == 1 && op->getRegion(0).getBlocks().size() == 1 &&
232          "expected linalg operation to have one block.");
233   Block &block = op->getRegion(0).front();
234 
235   for (IndexOp indexOp : block.getOps<linalg::IndexOp>()) {
236     auto rangeIndex = loopIndexToRangeIndex.find(indexOp.dim());
237     if (rangeIndex == loopIndexToRangeIndex.end())
238       continue;
239     // Offset the index by the value of the corresponding induction variable and
240     // replace all uses of the previous value.
241     OpBuilder::InsertionGuard g(b);
242     b.setInsertionPointAfter(indexOp);
243     AffineExpr index, iv;
244     bindDims(b.getContext(), index, iv);
245     AffineApplyOp applyOp = b.create<AffineApplyOp>(
246         indexOp.getLoc(), index + iv,
247         ValueRange{indexOp.getResult(), ivs[rangeIndex->second]});
248     indexOp.getResult().replaceAllUsesExcept(
249         applyOp.getResult(), SmallPtrSet<Operation *, 1>{applyOp});
250   }
251 }
252 
253 template <typename LoopTy>
254 static Optional<TiledLinalgOp>
255 tileLinalgOpImpl(OpBuilder &b, LinalgOp op, ValueRange tileSizes,
256                  const LinalgTilingOptions &options) {
257   auto nLoops = op.getNumLoops();
258   // Initial tile sizes may be too big, only take the first nLoops.
259   tileSizes = tileSizes.take_front(nLoops);
260 
261   if (llvm::all_of(tileSizes, isZero))
262     return llvm::None;
263 
264   if (auto convOp = dyn_cast<linalg::ConvOp>(op.getOperation())) {
265     // For conv op only support tiling along batch dimension (which is the first
266     // loop).
267     if (convOp.padding() && !llvm::all_of(tileSizes.drop_front(), isZero))
268       return llvm::None;
269   }
270 
271   // 1. Build the tiled loop ranges.
272   auto allShapeSizes = op.createFlatListOfOperandDims(b, op.getLoc());
273   AffineMap shapeSizesToLoopsMap = op.getShapesToLoopsMap();
274   if (!shapeSizesToLoopsMap)
275     return llvm::None;
276 
277   SmallVector<Range, 4> loopRanges;
278   LoopIndexToRangeIndexMap loopIndexToRangeIndex;
279   std::tie(loopRanges, loopIndexToRangeIndex) = makeTiledLoopRanges(
280       b, op.getLoc(), shapeSizesToLoopsMap, allShapeSizes, tileSizes);
281 
282   SmallVector<Attribute, 4> iteratorTypes;
283   for (auto attr :
284        enumerate(op.iterator_types().cast<ArrayAttr>().getValue())) {
285     if (loopIndexToRangeIndex.count(attr.index()))
286       iteratorTypes.push_back(attr.value());
287   }
288   // If interchangeVector is empty, use the identity. Build the permutation map
289   // otherwise.
290   auto invPermutationMap =
291       AffineMap::getMultiDimIdentityMap(tileSizes.size(), b.getContext());
292   if (!options.interchangeVector.empty()) {
293     // Based on the pruned iterations (due to zero tile size), recompute the
294     // interchange vector.
295     SmallVector<unsigned, 4> interchangeVector;
296     interchangeVector.reserve(options.interchangeVector.size());
297     for (auto pos : options.interchangeVector) {
298       auto it = loopIndexToRangeIndex.find(pos);
299       if (it == loopIndexToRangeIndex.end())
300         continue;
301       interchangeVector.push_back(it->second);
302     }
303     // Interchange vector is guaranteed to be a permutation,
304     // `inversePermutation` must succeed.
305     invPermutationMap = inversePermutation(
306         AffineMap::getPermutationMap(interchangeVector, b.getContext()));
307     assert(invPermutationMap);
308     applyPermutationToVector(loopRanges, interchangeVector);
309     applyPermutationToVector(iteratorTypes, interchangeVector);
310   }
311 
312   // 2. Create the tiled loops.
313   LinalgOp res = op;
314   SmallVector<Value, 4> ivs, tensorResults;
315   GenerateLoopNest<LoopTy>::doit(
316       loopRanges, op, iteratorTypes,
317       [&](ValueRange localIvs, ValueRange iterArgs) -> scf::ValueVector {
318         auto &b = ScopedContext::getBuilderRef();
319         auto loc = ScopedContext::getLocation();
320         ivs.assign(localIvs.begin(), localIvs.end());
321 
322         // When an `interchangeVector` is present, it has been applied to the
323         // loop ranges and the iterator types. Apply its inverse to the
324         // resulting loop `ivs` to match the op definition.
325         SmallVector<Value, 4> interchangedIvs;
326         if (!options.interchangeVector.empty())
327           interchangedIvs = applyMapToValues(b, loc, invPermutationMap, ivs);
328         else
329           interchangedIvs.assign(ivs.begin(), ivs.end());
330 
331         assert(op.getNumOutputTensors() == iterArgs.size() &&
332                "num output tensors must match number of loop iter arguments");
333 
334         auto operands = llvm::to_vector<4>(op.getInputs());
335         SmallVector<Value, 4> outputBuffers = op.getOutputBuffers();
336         // TODO: thanks to simplifying assumption we do not need to worry about
337         // order of output buffers and tensors: there is only ever one kind.
338         assert(outputBuffers.empty() || iterArgs.empty());
339         operands.append(outputBuffers.begin(), outputBuffers.end());
340         operands.append(iterArgs.begin(), iterArgs.end());
341         auto sizeBounds =
342             applyMapToValues(b, loc, shapeSizesToLoopsMap, allShapeSizes);
343         SmallVector<Value, 4> tiledOperands = makeTiledShapes(
344             b, loc, op, operands, interchangedIvs, tileSizes, sizeBounds);
345         auto nonShapedOperands = op.getAssumedNonShapedOperands();
346         tiledOperands.append(nonShapedOperands.begin(),
347                              nonShapedOperands.end());
348 
349         // TODO: use an interface/adaptor to avoid leaking position in
350         // `tiledOperands`.
351         SmallVector<Type, 4> resultTensorTypes;
352         for (OpOperand *opOperand : op.getOutputTensorsOpOperands())
353           resultTensorTypes.push_back(
354               tiledOperands[opOperand->getOperandNumber()].getType());
355 
356         res = op.clone(b, loc, resultTensorTypes, tiledOperands);
357 
358         // Insert a subtensor_insert for each output tensor.
359         unsigned resultIdx = 0;
360         for (OpOperand *opOperand : op.getOutputTensorsOpOperands()) {
361           // TODO: use an interface/adaptor to avoid leaking position in
362           // `tiledOperands`.
363           Value outputTensor = tiledOperands[opOperand->getOperandNumber()];
364           if (auto subtensor = outputTensor.getDefiningOp<SubTensorOp>()) {
365             tensorResults.push_back(b.create<SubTensorInsertOp>(
366                 loc, subtensor.source().getType(), res->getResult(resultIdx),
367                 subtensor.source(), subtensor.offsets(), subtensor.sizes(),
368                 subtensor.strides(), subtensor.static_offsets(),
369                 subtensor.static_sizes(), subtensor.static_strides()));
370           } else {
371             tensorResults.push_back(res->getResult(resultIdx));
372           }
373           ++resultIdx;
374         }
375         return scf::ValueVector(tensorResults.begin(), tensorResults.end());
376       },
377       options.distribution);
378 
379   // 3a. Transforms index arguments of `linalg.generic` w.r.t. to the tiling.
380   transformIndexedGenericOpIndices(b, res, ivs, loopIndexToRangeIndex);
381   // 3b. Transform IndexOp results w.r.t. the tiling.
382   transformIndexOps(b, res, ivs, loopIndexToRangeIndex);
383 
384   // 4. Gather the newly created loops and return them with the new op.
385   SmallVector<Operation *, 8> loops;
386   loops.reserve(ivs.size());
387   for (auto iv : ivs) {
388     if (iv.isa<BlockArgument>()) {
389       loops.push_back(iv.cast<BlockArgument>().getOwner()->getParentOp());
390       assert(loops.back() && "no owner found for induction variable!");
391     } else {
392       // TODO: Instead of doing this, try to recover the ops used instead of the
393       // loop.
394       loops.push_back(nullptr);
395     }
396   }
397 
398   // 5. Get the tensor results from the outermost loop if available. Otherwise
399   // use the previously captured `tensorResults`.
400   Operation *outermostLoop = nullptr;
401   for (Operation *loop : loops)
402     if ((outermostLoop = loop))
403       break;
404 
405   return TiledLinalgOp{
406       res, loops, outermostLoop ? outermostLoop->getResults() : tensorResults};
407 }
408 
409 template <typename LoopTy>
410 Optional<TiledLinalgOp> static tileLinalgOpImpl(
411     OpBuilder &b, LinalgOp op, const LinalgTilingOptions &options) {
412   OpBuilder::InsertionGuard g(b);
413   b.setInsertionPoint(op);
414   ScopedContext scope(b, op.getLoc());
415 
416   if (!options.tileSizeComputationFunction)
417     return llvm::None;
418 
419   // Enforce the convention that "tiling by zero" skips tiling a particular
420   // dimension. This convention is significantly simpler to handle instead of
421   // adjusting affine maps to account for missing dimensions.
422   auto nLoops = op.getNumLoops();
423   SmallVector<Value, 4> tileSizeVector =
424       options.tileSizeComputationFunction(b, op);
425   if (tileSizeVector.size() < nLoops) {
426     auto zero = std_constant_index(0);
427     tileSizeVector.append(nLoops - tileSizeVector.size(), zero);
428   }
429 
430   return tileLinalgOpImpl<LoopTy>(b, op, tileSizeVector, options);
431 }
432 
433 Optional<TiledLinalgOp>
434 mlir::linalg::tileLinalgOp(OpBuilder &b, LinalgOp op,
435                            const LinalgTilingOptions &options) {
436   switch (options.loopType) {
437   case LinalgTilingLoopType::Loops:
438     return tileLinalgOpImpl<scf::ForOp>(b, op, options);
439   case LinalgTilingLoopType::ParallelLoops:
440     return tileLinalgOpImpl<scf::ParallelOp>(b, op, options);
441   case LinalgTilingLoopType::TiledLoops:
442     return tileLinalgOpImpl<linalg::TiledLoopOp>(b, op, options);
443   default:;
444   }
445   return llvm::None;
446 }
447 
448 namespace {
449 /// Helper classes for type list expansion.
450 template <typename... OpTypes>
451 class CanonicalizationPatternList;
452 
453 template <>
454 class CanonicalizationPatternList<> {
455 public:
456   static void insert(RewritePatternSet &patterns) {}
457 };
458 
459 template <typename OpTy, typename... OpTypes>
460 class CanonicalizationPatternList<OpTy, OpTypes...> {
461 public:
462   static void insert(RewritePatternSet &patterns) {
463     OpTy::getCanonicalizationPatterns(patterns, patterns.getContext());
464     CanonicalizationPatternList<OpTypes...>::insert(patterns);
465   }
466 };
467 
468 /// Helper classes for type list expansion.
469 template <typename... OpTypes>
470 class RewritePatternList;
471 
472 template <>
473 class RewritePatternList<> {
474 public:
475   static void insert(RewritePatternSet &patterns,
476                      const LinalgTilingOptions &options) {}
477 };
478 
479 template <typename OpTy, typename... OpTypes>
480 class RewritePatternList<OpTy, OpTypes...> {
481 public:
482   static void insert(RewritePatternSet &patterns,
483                      const LinalgTilingOptions &options) {
484     auto *ctx = patterns.getContext();
485     patterns.add<LinalgTilingPattern<OpTy>>(
486         ctx, options,
487         LinalgTransformationFilter(ArrayRef<Identifier>{},
488                                    Identifier::get("tiled", ctx)));
489     RewritePatternList<OpTypes...>::insert(patterns, options);
490   }
491 };
492 } // namespace
493 
494 RewritePatternSet
495 mlir::linalg::getLinalgTilingCanonicalizationPatterns(MLIRContext *ctx) {
496   RewritePatternSet patterns(ctx);
497   populateLinalgTilingCanonicalizationPatterns(patterns);
498   return patterns;
499 }
500 
501 void mlir::linalg::populateLinalgTilingCanonicalizationPatterns(
502     RewritePatternSet &patterns) {
503   auto *ctx = patterns.getContext();
504   AffineApplyOp::getCanonicalizationPatterns(patterns, ctx);
505   AffineForOp::getCanonicalizationPatterns(patterns, ctx);
506   AffineMinOp::getCanonicalizationPatterns(patterns, ctx);
507   AffineMaxOp::getCanonicalizationPatterns(patterns, ctx);
508   scf::ForOp::getCanonicalizationPatterns(patterns, ctx);
509   scf::ParallelOp::getCanonicalizationPatterns(patterns, ctx);
510   ConstantIndexOp::getCanonicalizationPatterns(patterns, ctx);
511   SubTensorOp::getCanonicalizationPatterns(patterns, ctx);
512   memref::SubViewOp::getCanonicalizationPatterns(patterns, ctx);
513   tensor::CastOp::getCanonicalizationPatterns(patterns, ctx);
514   memref::ViewOp::getCanonicalizationPatterns(patterns, ctx);
515   CanonicalizationPatternList<
516 #define GET_OP_LIST
517 #include "mlir/Dialect/Linalg/IR/LinalgStructuredOps.cpp.inc"
518       >::insert(patterns);
519 }
520 
521 /// Populate the given list with patterns that apply Linalg tiling.
522 static void insertTilingPatterns(RewritePatternSet &patterns,
523                                  const LinalgTilingOptions &options) {
524   RewritePatternList<GenericOp, IndexedGenericOp,
525 #define GET_OP_LIST
526 #include "mlir/Dialect/Linalg/IR/LinalgStructuredOps.cpp.inc"
527                      >::insert(patterns, options);
528 }
529 
530 static void applyTilingToLoopPatterns(LinalgTilingLoopType loopType,
531                                       FuncOp funcOp,
532                                       ArrayRef<int64_t> tileSizes) {
533   auto options =
534       LinalgTilingOptions().setTileSizes(tileSizes).setLoopType(loopType);
535   MLIRContext *ctx = funcOp.getContext();
536   RewritePatternSet patterns(ctx);
537   insertTilingPatterns(patterns, options);
538   (void)applyPatternsAndFoldGreedily(funcOp, std::move(patterns));
539   (void)applyPatternsAndFoldGreedily(
540       funcOp, getLinalgTilingCanonicalizationPatterns(ctx));
541   // Drop the marker.
542   funcOp.walk([](LinalgOp op) {
543     op->removeAttr(LinalgTransforms::kLinalgTransformMarker);
544   });
545 }
546 
547 namespace {
548 struct LinalgTilingPass : public LinalgTilingBase<LinalgTilingPass> {
549   LinalgTilingPass() = default;
550   LinalgTilingPass(ArrayRef<int64_t> sizes) { tileSizes = sizes; }
551 
552   void runOnFunction() override {
553     applyTilingToLoopPatterns(LinalgTilingLoopType::Loops, getFunction(),
554                               tileSizes);
555   }
556 };
557 
558 struct LinalgTilingToParallelLoopsPass
559     : public LinalgTilingToParallelLoopsBase<LinalgTilingToParallelLoopsPass> {
560   LinalgTilingToParallelLoopsPass() = default;
561   LinalgTilingToParallelLoopsPass(ArrayRef<int64_t> sizes) {
562     tileSizes = sizes;
563   }
564 
565   void runOnFunction() override {
566     applyTilingToLoopPatterns(LinalgTilingLoopType::ParallelLoops,
567                               getFunction(), tileSizes);
568   }
569 };
570 
571 struct LinalgTilingToTiledLoopsPass
572     : public LinalgTilingToTiledLoopsBase<LinalgTilingToTiledLoopsPass> {
573   LinalgTilingToTiledLoopsPass() = default;
574   LinalgTilingToTiledLoopsPass(ArrayRef<int64_t> sizes) { tileSizes = sizes; }
575 
576   void runOnFunction() override {
577     applyTilingToLoopPatterns(LinalgTilingLoopType::TiledLoops, getFunction(),
578                               tileSizes);
579   }
580 };
581 
582 } // namespace
583 
584 std::unique_ptr<OperationPass<FuncOp>>
585 mlir::createLinalgTilingPass(ArrayRef<int64_t> tileSizes) {
586   return std::make_unique<LinalgTilingPass>(tileSizes);
587 }
588 
589 std::unique_ptr<OperationPass<FuncOp>>
590 mlir::createLinalgTilingToParallelLoopsPass(ArrayRef<int64_t> tileSizes) {
591   return std::make_unique<LinalgTilingToParallelLoopsPass>(tileSizes);
592 }
593 
594 std::unique_ptr<OperationPass<FuncOp>>
595 mlir::createLinalgTilingToTiledLoopPass(ArrayRef<int64_t> tileSizes) {
596   return std::make_unique<LinalgTilingToTiledLoopsPass>(tileSizes);
597 }
598