1 | //===----------------------------------------------------------------------===// |
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 | #include "mlir/Dialect/Arith/IR/Arith.h" |
10 | #include "mlir/Dialect/Bufferization/IR/BufferizableOpInterface.h" |
11 | #include "mlir/Dialect/Bufferization/IR/Bufferization.h" |
12 | #include "mlir/Dialect/Func/IR/FuncOps.h" |
13 | #include "mlir/Dialect/MemRef/IR/MemRef.h" |
14 | #include "mlir/Dialect/SparseTensor/IR/SparseTensor.h" |
15 | #include "mlir/Dialect/Tensor/IR/Tensor.h" |
16 | #include "mlir/IR/Matchers.h" |
17 | #include <optional> |
18 | |
19 | using namespace mlir; |
20 | using namespace mlir::bufferization; |
21 | |
22 | //===----------------------------------------------------------------------===// |
23 | // Helper functions |
24 | //===----------------------------------------------------------------------===// |
25 | |
26 | FailureOr<Value> mlir::bufferization::castOrReallocMemRefValue( |
27 | OpBuilder &b, Value value, MemRefType destType, |
28 | const BufferizationOptions &options) { |
29 | auto srcType = llvm::cast<MemRefType>(value.getType()); |
30 | |
31 | // Element type and rank must match. |
32 | if (srcType.getElementType() != destType.getElementType()) |
33 | return failure(); |
34 | if (srcType.getRank() != destType.getRank()) |
35 | return failure(); |
36 | |
37 | // In case the affine maps are different, we may need to use a copy if we go |
38 | // from dynamic to static offset or stride (the canonicalization cannot know |
39 | // at this point that it is really cast compatible). |
40 | auto isGuaranteedCastCompatible = [](MemRefType source, MemRefType target) { |
41 | int64_t sourceOffset, targetOffset; |
42 | SmallVector<int64_t, 4> sourceStrides, targetStrides; |
43 | if (failed(source.getStridesAndOffset(sourceStrides, sourceOffset)) || |
44 | failed(target.getStridesAndOffset(targetStrides, targetOffset))) |
45 | return false; |
46 | auto dynamicToStatic = [](int64_t a, int64_t b) { |
47 | return ShapedType::isDynamic(a) && !ShapedType::isDynamic(b); |
48 | }; |
49 | if (dynamicToStatic(sourceOffset, targetOffset)) |
50 | return false; |
51 | for (auto it : zip(t&: sourceStrides, u&: targetStrides)) |
52 | if (dynamicToStatic(std::get<0>(t&: it), std::get<1>(t&: it))) |
53 | return false; |
54 | return true; |
55 | }; |
56 | |
57 | // Note: If `areCastCompatible`, a cast is valid, but may fail at runtime. To |
58 | // ensure that we only generate casts that always succeed at runtime, we check |
59 | // a fix extra conditions in `isGuaranteedCastCompatible`. |
60 | if (memref::CastOp::areCastCompatible(srcType, destType) && |
61 | isGuaranteedCastCompatible(srcType, destType)) { |
62 | Value casted = b.create<memref::CastOp>(value.getLoc(), destType, value); |
63 | return casted; |
64 | } |
65 | |
66 | auto loc = value.getLoc(); |
67 | SmallVector<Value, 4> dynamicOperands; |
68 | for (int i = 0; i < destType.getRank(); ++i) { |
69 | if (destType.getShape()[i] != ShapedType::kDynamic) |
70 | continue; |
71 | Value size = b.create<memref::DimOp>(loc, value, i); |
72 | dynamicOperands.push_back(Elt: size); |
73 | } |
74 | |
75 | FailureOr<Value> copy = |
76 | options.createAlloc(b, loc, type: destType, dynShape: dynamicOperands); |
77 | if (failed(Result: copy)) |
78 | return failure(); |
79 | if (failed(Result: options.createMemCpy(b, loc, from: value, to: *copy))) |
80 | return failure(); |
81 | return copy; |
82 | } |
83 | |
84 | /// Try to fold to_buffer(to_tensor(x)). If x's type and the result type of the |
85 | /// to_buffer op are different, a memref.cast is needed. |
86 | LogicalResult mlir::bufferization::foldToBufferToTensorPair( |
87 | RewriterBase &rewriter, ToBufferOp toBuffer, |
88 | const BufferizationOptions &options) { |
89 | auto bufferToTensor = toBuffer.getTensor().getDefiningOp<ToTensorOp>(); |
90 | if (!bufferToTensor) |
91 | return failure(); |
92 | |
93 | Type srcType = bufferToTensor.getMemref().getType(); |
94 | Type destType = toBuffer.getType(); |
95 | |
96 | // Directly rewrite if the type did not change. |
97 | if (srcType == destType) { |
98 | rewriter.replaceOp(toBuffer, bufferToTensor.getMemref()); |
99 | return success(); |
100 | } |
101 | |
102 | auto rankedSrcType = llvm::dyn_cast<MemRefType>(srcType); |
103 | auto rankedDestType = llvm::dyn_cast<MemRefType>(destType); |
104 | auto unrankedSrcType = llvm::dyn_cast<UnrankedMemRefType>(srcType); |
105 | |
106 | // Ranked memref -> Ranked memref cast. |
107 | if (rankedSrcType && rankedDestType) { |
108 | FailureOr<Value> replacement = castOrReallocMemRefValue( |
109 | rewriter, bufferToTensor.getMemref(), rankedDestType, options); |
110 | if (failed(Result: replacement)) |
111 | return failure(); |
112 | |
113 | rewriter.replaceOp(toBuffer, *replacement); |
114 | return success(); |
115 | } |
116 | |
117 | // Unranked memref -> Ranked memref cast: May require a copy. |
118 | // TODO: Not implemented at the moment. |
119 | if (unrankedSrcType && rankedDestType) |
120 | return failure(); |
121 | |
122 | // Unranked memref -> unranked memref cast |
123 | // Ranked memref -> unranked memref cast: No copy needed. |
124 | assert(memref::CastOp::areCastCompatible(srcType, destType) && |
125 | "expected that types are cast compatible" ); |
126 | rewriter.replaceOpWithNewOp<memref::CastOp>(toBuffer, destType, |
127 | bufferToTensor.getMemref()); |
128 | return success(); |
129 | } |
130 | |
131 | void mlir::bufferization::populateDynamicDimSizes( |
132 | OpBuilder &b, Location loc, Value shapedValue, |
133 | SmallVector<Value> &dynamicDims) { |
134 | auto shapedType = llvm::cast<ShapedType>(shapedValue.getType()); |
135 | for (int64_t i = 0; i < shapedType.getRank(); ++i) { |
136 | if (shapedType.isDynamicDim(i)) { |
137 | if (llvm::isa<MemRefType>(shapedType)) { |
138 | dynamicDims.push_back(b.create<memref::DimOp>(loc, shapedValue, i)); |
139 | } else { |
140 | assert(llvm::isa<RankedTensorType>(shapedType) && "expected tensor" ); |
141 | dynamicDims.push_back(b.create<tensor::DimOp>(loc, shapedValue, i)); |
142 | } |
143 | } |
144 | } |
145 | } |
146 | |
147 | //===----------------------------------------------------------------------===// |
148 | // AllocTensorOp |
149 | //===----------------------------------------------------------------------===// |
150 | |
151 | LogicalResult AllocTensorOp::bufferize(RewriterBase &rewriter, |
152 | const BufferizationOptions &options, |
153 | BufferizationState &state) { |
154 | OpBuilder::InsertionGuard g(rewriter); |
155 | Location loc = getLoc(); |
156 | |
157 | // Nothing to do for dead AllocTensorOps. |
158 | if (getOperation()->getUses().empty()) { |
159 | rewriter.eraseOp(getOperation()); |
160 | return success(); |
161 | } |
162 | |
163 | // Get "copy" buffer. |
164 | Value copyBuffer; |
165 | if (getCopy()) { |
166 | FailureOr<Value> maybeCopyBuffer = |
167 | getBuffer(rewriter, getCopy(), options, state); |
168 | if (failed(maybeCopyBuffer)) |
169 | return failure(); |
170 | copyBuffer = *maybeCopyBuffer; |
171 | } |
172 | |
173 | // Create memory allocation. |
174 | auto allocType = bufferization::getBufferType(getResult(), options, state); |
175 | if (failed(allocType)) |
176 | return failure(); |
177 | SmallVector<Value> dynamicDims = getDynamicSizes(); |
178 | if (getCopy()) { |
179 | assert(dynamicDims.empty() && "expected either `copy` or `dynamicDims`" ); |
180 | populateDynamicDimSizes(rewriter, loc, copyBuffer, dynamicDims); |
181 | } |
182 | FailureOr<Value> alloc = options.createAlloc( |
183 | rewriter, loc, llvm::cast<MemRefType>(*allocType), dynamicDims); |
184 | if (failed(alloc)) |
185 | return failure(); |
186 | |
187 | // Create memory copy (if any). |
188 | if (getCopy()) { |
189 | if (failed(options.createMemCpy(rewriter, loc, copyBuffer, *alloc))) |
190 | return failure(); |
191 | } |
192 | |
193 | // Replace op. |
194 | replaceOpWithBufferizedValues(rewriter, getOperation(), *alloc); |
195 | |
196 | return success(); |
197 | } |
198 | |
199 | bool AllocTensorOp::resultBufferizesToMemoryWrite(OpResult opResult, |
200 | const AnalysisState &state) { |
201 | // AllocTensorOps do not write unless they have a `copy` value. |
202 | return static_cast<bool>(getCopy()); |
203 | } |
204 | |
205 | bool AllocTensorOp::bufferizesToMemoryRead(OpOperand &opOperand, |
206 | const AnalysisState &state) { |
207 | assert(opOperand.getOperandNumber() == getNumOperands() - 1 && |
208 | "expected copy operand" ); |
209 | return true; |
210 | } |
211 | |
212 | bool AllocTensorOp::bufferizesToMemoryWrite(OpOperand &opOperand, |
213 | const AnalysisState &state) { |
214 | assert(opOperand.getOperandNumber() == getNumOperands() - 1 && |
215 | "expected copy operand" ); |
216 | return false; |
217 | } |
218 | |
219 | AliasingValueList AllocTensorOp::getAliasingValues(OpOperand &opOperand, |
220 | const AnalysisState &state) { |
221 | // This is a new allocation. It does not alias with any other buffer. |
222 | return {}; |
223 | } |
224 | |
225 | FailureOr<BaseMemRefType> |
226 | AllocTensorOp::getBufferType(Value value, const BufferizationOptions &options, |
227 | const BufferizationState &state, |
228 | SmallVector<Value> &invocationStack) { |
229 | assert(value == getResult() && "invalid value" ); |
230 | |
231 | // Compute memory space of this allocation. |
232 | Attribute memorySpace; |
233 | if (getMemorySpace().has_value()) { |
234 | memorySpace = *getMemorySpace(); |
235 | } else if (getCopy()) { |
236 | auto copyBufferType = bufferization::getBufferType(getCopy(), options, |
237 | state, invocationStack); |
238 | if (failed(copyBufferType)) |
239 | return failure(); |
240 | memorySpace = copyBufferType->getMemorySpace(); |
241 | } else if (auto ms = options.defaultMemorySpaceFn(getType())) { |
242 | memorySpace = *ms; |
243 | } else { |
244 | return getOperation()->emitError("could not infer memory space" ); |
245 | } |
246 | |
247 | return getMemRefTypeWithStaticIdentityLayout(getType(), memorySpace); |
248 | } |
249 | |
250 | LogicalResult AllocTensorOp::verify() { |
251 | if (getCopy() && !getDynamicSizes().empty()) |
252 | return emitError("dynamic sizes not needed when copying a tensor" ); |
253 | if (!getCopy() && getType().getNumDynamicDims() != getDynamicSizes().size()) |
254 | return emitError("expected " ) |
255 | << getType().getNumDynamicDims() << " dynamic sizes" ; |
256 | if (getCopy() && getCopy().getType() != getType()) |
257 | return emitError("expected that `copy` and return type match" ); |
258 | return success(); |
259 | } |
260 | |
261 | void AllocTensorOp::build(OpBuilder &builder, OperationState &result, |
262 | RankedTensorType type, ValueRange dynamicSizes) { |
263 | build(builder, result, type, dynamicSizes, /*copy=*/Value(), |
264 | /*size_hint=*/Value(), |
265 | /*memory_space=*/IntegerAttr()); |
266 | } |
267 | |
268 | void AllocTensorOp::build(OpBuilder &builder, OperationState &result, |
269 | RankedTensorType type, ValueRange dynamicSizes, |
270 | Value copy) { |
271 | build(builder, result, type, dynamicSizes, copy, /*size_hint=*/Value(), |
272 | /*memory_space=*/IntegerAttr()); |
273 | } |
274 | |
275 | void AllocTensorOp::build(OpBuilder &builder, OperationState &result, |
276 | TensorType type, ValueRange dynamicSizes, Value copy, |
277 | IntegerAttr memorySpace) { |
278 | build(builder, result, type, dynamicSizes, copy, /*size_hint=*/Value(), |
279 | memorySpace); |
280 | } |
281 | |
282 | namespace { |
283 | /// Change the type of the result of a `bufferization.alloc_tensor` by making |
284 | /// the result type statically sized along dimension that in the original |
285 | /// operation where defined as dynamic, but the size was defined using a |
286 | /// `constant` op. For example: |
287 | /// |
288 | /// %c5 = arith.constant 5: index |
289 | /// %0 = bufferization.alloc_tensor(%arg0, %c5) : tensor<?x?xf32> |
290 | /// |
291 | /// to |
292 | /// |
293 | /// %0 = bufferization.alloc_tensor(%arg0) : tensor<?x5xf32> |
294 | struct ReplaceStaticShapeDims : OpRewritePattern<AllocTensorOp> { |
295 | using OpRewritePattern<AllocTensorOp>::OpRewritePattern; |
296 | |
297 | LogicalResult matchAndRewrite(AllocTensorOp op, |
298 | PatternRewriter &rewriter) const override { |
299 | if (op.getCopy()) |
300 | return failure(); |
301 | SmallVector<int64_t> newShape = llvm::to_vector(op.getType().getShape()); |
302 | SmallVector<Value> newDynamicSizes; |
303 | unsigned int dynValCounter = 0; |
304 | for (int64_t i = 0; i < op.getType().getRank(); ++i) { |
305 | if (!op.isDynamicDim(i)) |
306 | continue; |
307 | Value value = op.getDynamicSizes()[dynValCounter++]; |
308 | APInt intVal; |
309 | if (matchPattern(value, m_ConstantInt(&intVal))) { |
310 | int64_t dim = intVal.getSExtValue(); |
311 | if (dim >= 0) |
312 | newShape[i] = intVal.getSExtValue(); |
313 | else |
314 | newDynamicSizes.push_back(Elt: value); |
315 | } else { |
316 | newDynamicSizes.push_back(Elt: value); |
317 | } |
318 | } |
319 | RankedTensorType newType = RankedTensorType::get( |
320 | newShape, op.getType().getElementType(), op.getType().getEncoding()); |
321 | if (newType == op.getType()) |
322 | return failure(); |
323 | auto newOp = rewriter.create<AllocTensorOp>( |
324 | op.getLoc(), newType, newDynamicSizes, /*copy=*/Value()); |
325 | rewriter.replaceOpWithNewOp<tensor::CastOp>(op, op.getType(), newOp); |
326 | return success(); |
327 | } |
328 | }; |
329 | |
330 | struct FoldDimOfAllocTensorOp : public OpRewritePattern<tensor::DimOp> { |
331 | using OpRewritePattern<tensor::DimOp>::OpRewritePattern; |
332 | |
333 | LogicalResult matchAndRewrite(tensor::DimOp dimOp, |
334 | PatternRewriter &rewriter) const override { |
335 | std::optional<int64_t> maybeConstantIndex = dimOp.getConstantIndex(); |
336 | auto allocTensorOp = dimOp.getSource().getDefiningOp<AllocTensorOp>(); |
337 | if (!allocTensorOp || !maybeConstantIndex) |
338 | return failure(); |
339 | if (*maybeConstantIndex < 0 || |
340 | *maybeConstantIndex >= allocTensorOp.getType().getRank()) |
341 | return failure(); |
342 | if (!allocTensorOp.getType().isDynamicDim(*maybeConstantIndex)) |
343 | return failure(); |
344 | rewriter.replaceOp( |
345 | dimOp, allocTensorOp.getDynamicSize(rewriter, *maybeConstantIndex)); |
346 | return success(); |
347 | } |
348 | }; |
349 | } // namespace |
350 | |
351 | void AllocTensorOp::getCanonicalizationPatterns(RewritePatternSet &results, |
352 | MLIRContext *ctx) { |
353 | results.add<FoldDimOfAllocTensorOp, ReplaceStaticShapeDims>(ctx); |
354 | } |
355 | |
356 | LogicalResult AllocTensorOp::reifyResultShapes( |
357 | OpBuilder &builder, ReifiedRankedShapedTypeDims &reifiedReturnShapes) { |
358 | auto shapes = llvm::to_vector<4>( |
359 | llvm::map_range(llvm::seq<int64_t>(0, getType().getRank()), |
360 | [&](int64_t dim) -> OpFoldResult { |
361 | if (isDynamicDim(dim)) |
362 | return getDynamicSize(builder, dim); |
363 | return builder.getIndexAttr(getStaticSize(dim)); |
364 | })); |
365 | reifiedReturnShapes.emplace_back(std::move(shapes)); |
366 | return success(); |
367 | } |
368 | |
369 | ParseResult AllocTensorOp::parse(OpAsmParser &parser, OperationState &result) { |
370 | SmallVector<OpAsmParser::UnresolvedOperand> dynamicSizesOperands; |
371 | if (parser.parseLParen() || parser.parseOperandList(dynamicSizesOperands) || |
372 | parser.parseRParen()) |
373 | return failure(); |
374 | ParseResult copyKeyword = parser.parseOptionalKeyword("copy" ); |
375 | OpAsmParser::UnresolvedOperand copyOperand; |
376 | if (copyKeyword.succeeded()) |
377 | if (parser.parseLParen() || parser.parseOperand(copyOperand) || |
378 | parser.parseRParen()) |
379 | return failure(); |
380 | ParseResult sizeHintKeyword = parser.parseOptionalKeyword("size_hint" ); |
381 | OpAsmParser::UnresolvedOperand sizeHintOperand; |
382 | if (sizeHintKeyword.succeeded()) |
383 | if (parser.parseEqual() || parser.parseOperand(sizeHintOperand)) |
384 | return failure(); |
385 | if (parser.parseOptionalAttrDict(result.attributes) || parser.parseColon()) |
386 | return failure(); |
387 | |
388 | TensorType type; |
389 | if (parser.parseCustomTypeWithFallback(type)) |
390 | return failure(); |
391 | result.addTypes(type); |
392 | |
393 | Type indexType = parser.getBuilder().getIndexType(); |
394 | if (parser.resolveOperands(dynamicSizesOperands, indexType, result.operands)) |
395 | return failure(); |
396 | if (copyKeyword.succeeded()) |
397 | if (parser.resolveOperand(copyOperand, type, result.operands)) |
398 | return failure(); |
399 | if (sizeHintKeyword.succeeded()) |
400 | if (parser.resolveOperand(sizeHintOperand, indexType, result.operands)) |
401 | return failure(); |
402 | result.addAttribute(AllocTensorOp::getOperandSegmentSizeAttr(), |
403 | parser.getBuilder().getDenseI32ArrayAttr( |
404 | {static_cast<int32_t>(dynamicSizesOperands.size()), |
405 | static_cast<int32_t>(copyKeyword.succeeded()), |
406 | static_cast<int32_t>(sizeHintKeyword.succeeded())})); |
407 | return success(); |
408 | } |
409 | |
410 | void AllocTensorOp::print(OpAsmPrinter &p) { |
411 | p << "(" << getDynamicSizes() << ")" ; |
412 | if (getCopy()) |
413 | p << " copy(" << getCopy() << ")" ; |
414 | if (getSizeHint()) |
415 | p << " size_hint=" << getSizeHint(); |
416 | p.printOptionalAttrDict((*this)->getAttrs(), /*elidedAttrs=*/{ |
417 | AllocTensorOp::getOperandSegmentSizeAttr()}); |
418 | p << " : " ; |
419 | auto type = getResult().getType(); |
420 | if (auto validType = llvm::dyn_cast<::mlir::TensorType>(type)) |
421 | p.printStrippedAttrOrType(validType); |
422 | else |
423 | p << type; |
424 | } |
425 | |
426 | Value AllocTensorOp::getDynamicSize(OpBuilder &b, unsigned idx) { |
427 | assert(isDynamicDim(idx) && "expected dynamic dim" ); |
428 | if (getCopy()) |
429 | return b.create<tensor::DimOp>(getLoc(), getCopy(), idx); |
430 | return getOperand(getIndexOfDynamicSize(idx)); |
431 | } |
432 | |
433 | //===----------------------------------------------------------------------===// |
434 | // CloneOp |
435 | //===----------------------------------------------------------------------===// |
436 | |
437 | OpFoldResult CloneOp::fold(FoldAdaptor adaptor) { |
438 | return succeeded(memref::foldMemRefCast(*this)) ? getResult() : Value(); |
439 | } |
440 | |
441 | namespace { |
442 | |
443 | /// Merge the clone and its source (by converting the clone to a cast) when |
444 | /// possible. |
445 | struct SimplifyClones : public OpRewritePattern<CloneOp> { |
446 | using OpRewritePattern<CloneOp>::OpRewritePattern; |
447 | |
448 | LogicalResult matchAndRewrite(CloneOp cloneOp, |
449 | PatternRewriter &rewriter) const override { |
450 | if (cloneOp.use_empty()) { |
451 | rewriter.eraseOp(op: cloneOp); |
452 | return success(); |
453 | } |
454 | |
455 | Value source = cloneOp.getInput(); |
456 | if (source.getType() != cloneOp.getType() && |
457 | !memref::CastOp::areCastCompatible({source.getType()}, |
458 | {cloneOp.getType()})) |
459 | return failure(); |
460 | |
461 | // Aims to find the dealloc op for the canonical source |
462 | // which otherwise could prevent removal of unnecessary allocs. |
463 | Value canonicalSource = source; |
464 | while (auto iface = dyn_cast_or_null<ViewLikeOpInterface>( |
465 | canonicalSource.getDefiningOp())) |
466 | canonicalSource = iface.getViewSource(); |
467 | |
468 | std::optional<Operation *> maybeCloneDeallocOp = |
469 | memref::findDealloc(allocValue: cloneOp.getOutput()); |
470 | // Skip if either of them has > 1 deallocate operations. |
471 | if (!maybeCloneDeallocOp.has_value()) |
472 | return failure(); |
473 | std::optional<Operation *> maybeSourceDeallocOp = |
474 | memref::findDealloc(allocValue: canonicalSource); |
475 | if (!maybeSourceDeallocOp.has_value()) |
476 | return failure(); |
477 | Operation *cloneDeallocOp = *maybeCloneDeallocOp; |
478 | Operation *sourceDeallocOp = *maybeSourceDeallocOp; |
479 | |
480 | // If both are deallocated in the same block, their in-block lifetimes |
481 | // might not fully overlap, so we cannot decide which one to drop. |
482 | if (cloneDeallocOp && sourceDeallocOp && |
483 | cloneDeallocOp->getBlock() == sourceDeallocOp->getBlock()) |
484 | return failure(); |
485 | |
486 | Block *currentBlock = cloneOp->getBlock(); |
487 | Operation *redundantDealloc = nullptr; |
488 | if (cloneDeallocOp && cloneDeallocOp->getBlock() == currentBlock) { |
489 | redundantDealloc = cloneDeallocOp; |
490 | } else if (sourceDeallocOp && sourceDeallocOp->getBlock() == currentBlock) { |
491 | redundantDealloc = sourceDeallocOp; |
492 | } |
493 | |
494 | if (!redundantDealloc) |
495 | return failure(); |
496 | |
497 | // Safety check that there are no other deallocations inbetween |
498 | // cloneOp and redundantDealloc, as otherwise we might deallocate an alias |
499 | // of source before the uses of the clone. With alias information, we could |
500 | // restrict this to only fail of the dealloc's operand is an alias |
501 | // of the source. |
502 | for (Operation *pos = cloneOp->getNextNode(); pos != redundantDealloc; |
503 | pos = pos->getNextNode()) { |
504 | // Bail if we run out of operations while looking for a deallocation op. |
505 | if (!pos) |
506 | return failure(); |
507 | auto effectInterface = dyn_cast<MemoryEffectOpInterface>(pos); |
508 | if (!effectInterface) |
509 | continue; |
510 | if (effectInterface.hasEffect<MemoryEffects::Free>()) |
511 | return failure(); |
512 | } |
513 | |
514 | if (source.getType() != cloneOp.getType()) |
515 | source = rewriter.create<memref::CastOp>(cloneOp.getLoc(), |
516 | cloneOp.getType(), source); |
517 | rewriter.replaceOp(cloneOp, source); |
518 | rewriter.eraseOp(op: redundantDealloc); |
519 | return success(); |
520 | } |
521 | }; |
522 | |
523 | } // namespace |
524 | |
525 | void CloneOp::getCanonicalizationPatterns(RewritePatternSet &results, |
526 | MLIRContext *context) { |
527 | results.add<SimplifyClones>(context); |
528 | } |
529 | |
530 | //===----------------------------------------------------------------------===// |
531 | // DeallocTensorOp |
532 | //===----------------------------------------------------------------------===// |
533 | |
534 | LogicalResult DeallocTensorOp::bufferize(RewriterBase &rewriter, |
535 | const BufferizationOptions &options, |
536 | BufferizationState &state) { |
537 | FailureOr<Value> buffer = getBuffer(rewriter, getTensor(), options, state); |
538 | if (failed(buffer)) |
539 | return failure(); |
540 | rewriter.create<memref::DeallocOp>(getLoc(), *buffer); |
541 | rewriter.eraseOp(getOperation()); |
542 | return success(); |
543 | } |
544 | |
545 | //===----------------------------------------------------------------------===// |
546 | // MaterializeInDestinationOp |
547 | //===----------------------------------------------------------------------===// |
548 | |
549 | bool MaterializeInDestinationOp::bufferizesToMemoryRead( |
550 | OpOperand &opOperand, const AnalysisState &state) { |
551 | return opOperand == getSourceMutable(); |
552 | } |
553 | |
554 | bool MaterializeInDestinationOp::bufferizesToMemoryWrite( |
555 | OpOperand &opOperand, const AnalysisState &state) { |
556 | if (opOperand == getDestMutable()) { |
557 | assert(isa<TensorType>(getDest().getType()) && "expected tensor type" ); |
558 | return true; |
559 | } |
560 | return false; |
561 | } |
562 | |
563 | bool MaterializeInDestinationOp::mustBufferizeInPlace( |
564 | OpOperand &opOperand, const AnalysisState &state) { |
565 | // The source is only read and not written, so it always bufferizes in-place |
566 | // by default. The destination is written and is forced to bufferize in-place |
567 | // (if it is a tensor). |
568 | return true; |
569 | } |
570 | |
571 | AliasingValueList |
572 | MaterializeInDestinationOp::getAliasingValues(OpOperand &opOperand, |
573 | const AnalysisState &state) { |
574 | if (opOperand == getDestMutable()) { |
575 | assert(isa<TensorType>(getDest().getType()) && "expected tensor type" ); |
576 | return {{getOperation()->getResult(0), BufferRelation::Equivalent}}; |
577 | } |
578 | return {}; |
579 | } |
580 | |
581 | LogicalResult |
582 | MaterializeInDestinationOp::bufferize(RewriterBase &rewriter, |
583 | const BufferizationOptions &options, |
584 | BufferizationState &state) { |
585 | bool tensorDest = isa<TensorType>(getDest().getType()); |
586 | Value buffer; |
587 | if (tensorDest) { |
588 | FailureOr<Value> maybeBuffer = |
589 | getBuffer(rewriter, getDest(), options, state); |
590 | if (failed(maybeBuffer)) |
591 | return failure(); |
592 | buffer = *maybeBuffer; |
593 | } else { |
594 | assert(isa<BaseMemRefType>(getDest().getType()) && "expected memref type" ); |
595 | buffer = getDest(); |
596 | } |
597 | auto srcBuffer = getBuffer(rewriter, getSource(), options, state); |
598 | if (failed(srcBuffer)) |
599 | return failure(); |
600 | if (failed(options.createMemCpy(rewriter, getLoc(), *srcBuffer, buffer))) |
601 | return failure(); |
602 | replaceOpWithBufferizedValues(rewriter, getOperation(), |
603 | tensorDest ? ValueRange(buffer) : ValueRange()); |
604 | return success(); |
605 | } |
606 | |
607 | bool MaterializeInDestinationOp::bufferizesToElementwiseAccess( |
608 | const AnalysisState &state, ArrayRef<OpOperand *> opOperands) { |
609 | // As elements are copied from the "source" buffer to the "dest" buffer, |
610 | // already copied elements are not read a second time. |
611 | return true; |
612 | } |
613 | |
614 | LogicalResult MaterializeInDestinationOp::reifyResultShapes( |
615 | OpBuilder &builder, ReifiedRankedShapedTypeDims &reifiedReturnShapes) { |
616 | if (getOperation()->getNumResults() == 1) { |
617 | assert(isa<TensorType>(getDest().getType()) && "expected tensor type" ); |
618 | reifiedReturnShapes.resize(1, |
619 | SmallVector<OpFoldResult>(getType().getRank())); |
620 | reifiedReturnShapes[0] = |
621 | tensor::getMixedSizes(builder, getLoc(), getDest()); |
622 | } |
623 | return success(); |
624 | } |
625 | |
626 | Value MaterializeInDestinationOp::buildSubsetExtraction(OpBuilder &builder, |
627 | Location loc) { |
628 | if (isa<TensorType>(getDest().getType())) { |
629 | // The subset is the entire destination tensor. |
630 | return getDest(); |
631 | } |
632 | |
633 | // The "restrict" attribute is transferred from this op to the newly created |
634 | // to_tensor op. If this op does not the "restrict" attribute, the subset |
635 | // extraction cannot be built because there is no guarantee that there is no |
636 | // pre-existing "restrict" to_tensor op with the same/an aliasing destination. |
637 | if (!getRestrict()) |
638 | return {}; |
639 | |
640 | // Build a bufferization.to_tensor op. |
641 | assert(isa<BaseMemRefType>(getDest().getType()) && "expected memref type" ); |
642 | assert(getRestrict() && |
643 | "expected that ops with memrefs dest have 'restrict'" ); |
644 | setRestrict(false); |
645 | return builder.create<ToTensorOp>(loc, getDest(), /*restrict=*/true, |
646 | getWritable()); |
647 | } |
648 | |
649 | bool MaterializeInDestinationOp::isEquivalentSubset( |
650 | Value candidate, function_ref<bool(Value, Value)> equivalenceFn) { |
651 | return equivalenceFn(getDest(), candidate); |
652 | } |
653 | |
654 | SmallVector<Value> |
655 | MaterializeInDestinationOp::getValuesNeededToBuildSubsetExtraction() { |
656 | return {getDest()}; |
657 | } |
658 | |
659 | OpOperand &MaterializeInDestinationOp::getSourceOperand() { |
660 | return getOperation()->getOpOperand(0) /*source*/; |
661 | } |
662 | |
663 | bool MaterializeInDestinationOp::operatesOnEquivalentSubset( |
664 | SubsetOpInterface subsetOp, |
665 | function_ref<bool(Value, Value)> equivalenceFn) { |
666 | return false; |
667 | } |
668 | |
669 | bool MaterializeInDestinationOp::operatesOnDisjointSubset( |
670 | SubsetOpInterface subsetOp, |
671 | function_ref<bool(Value, Value)> equivalenceFn) { |
672 | return false; |
673 | } |
674 | |
675 | LogicalResult MaterializeInDestinationOp::verify() { |
676 | if (!isa<TensorType, BaseMemRefType>(getDest().getType())) |
677 | return emitOpError("'dest' must be a tensor or a memref" ); |
678 | if (auto destType = dyn_cast<TensorType>(getDest().getType())) { |
679 | if (getOperation()->getNumResults() != 1) |
680 | return emitOpError("tensor 'dest' implies exactly one tensor result" ); |
681 | if (destType != getResult().getType()) |
682 | return emitOpError("result and 'dest' types must match" ); |
683 | } |
684 | if (isa<BaseMemRefType>(getDest().getType()) && |
685 | getOperation()->getNumResults() != 0) |
686 | return emitOpError("memref 'dest' implies zero results" ); |
687 | if (getRestrict() && !isa<BaseMemRefType>(getDest().getType())) |
688 | return emitOpError("'restrict' is valid only for memref destinations" ); |
689 | if (getWritable() != isa<BaseMemRefType>(getDest().getType())) |
690 | return emitOpError("'writable' must be specified if and only if the " |
691 | "destination is of memref type" ); |
692 | TensorType srcType = getSource().getType(); |
693 | ShapedType destType = cast<ShapedType>(getDest().getType()); |
694 | if (srcType.hasRank() != destType.hasRank()) |
695 | return emitOpError("source/destination shapes are incompatible" ); |
696 | if (srcType.hasRank()) { |
697 | if (srcType.getRank() != destType.getRank()) |
698 | return emitOpError("rank mismatch between source and destination shape" ); |
699 | for (auto [src, dest] : |
700 | llvm::zip(srcType.getShape(), destType.getShape())) { |
701 | if (src == ShapedType::kDynamic || dest == ShapedType::kDynamic) { |
702 | // Cannot verify dynamic dimension size. Assume that that they match at |
703 | // runtime. |
704 | continue; |
705 | } |
706 | if (src != dest) |
707 | return emitOpError("source/destination shapes are incompatible" ); |
708 | } |
709 | } |
710 | return success(); |
711 | } |
712 | |
713 | void MaterializeInDestinationOp::build(OpBuilder &builder, |
714 | OperationState &state, Value source, |
715 | Value dest) { |
716 | auto destTensorType = dyn_cast<TensorType>(dest.getType()); |
717 | build(builder, state, /*result=*/destTensorType ? destTensorType : Type(), |
718 | source, dest); |
719 | } |
720 | |
721 | bool MaterializeInDestinationOp::isWritable(Value value, |
722 | const AnalysisState &state) { |
723 | return isa<TensorType>(getDest().getType()) ? true : getWritable(); |
724 | } |
725 | |
726 | MutableOperandRange MaterializeInDestinationOp::getDpsInitsMutable() { |
727 | return getDestMutable(); |
728 | } |
729 | |
730 | void MaterializeInDestinationOp::getEffects( |
731 | SmallVectorImpl<SideEffects::EffectInstance<MemoryEffects::Effect>> |
732 | &effects) { |
733 | if (isa<BaseMemRefType>(getDest().getType())) |
734 | effects.emplace_back(MemoryEffects::Write::get(), &getDestMutable(), |
735 | SideEffects::DefaultResource::get()); |
736 | } |
737 | |
738 | //===----------------------------------------------------------------------===// |
739 | // ToTensorOp |
740 | //===----------------------------------------------------------------------===// |
741 | |
742 | bool ToTensorOp::isWritable(Value value, const AnalysisState &state) { |
743 | return getWritable(); |
744 | } |
745 | |
746 | OpFoldResult ToTensorOp::fold(FoldAdaptor) { |
747 | if (auto toBuffer = getMemref().getDefiningOp<ToBufferOp>()) |
748 | // Approximate alias analysis by conservatively folding only when no there |
749 | // is no interleaved operation. |
750 | if (toBuffer->getBlock() == this->getOperation()->getBlock() && |
751 | toBuffer->getNextNode() == this->getOperation()) |
752 | return toBuffer.getTensor(); |
753 | return {}; |
754 | } |
755 | |
756 | namespace { |
757 | struct DimOfToTensorFolder : public OpRewritePattern<tensor::DimOp> { |
758 | using OpRewritePattern<tensor::DimOp>::OpRewritePattern; |
759 | |
760 | LogicalResult matchAndRewrite(tensor::DimOp dimOp, |
761 | PatternRewriter &rewriter) const override { |
762 | auto memrefToTensorOp = dimOp.getSource().getDefiningOp<ToTensorOp>(); |
763 | if (!memrefToTensorOp) |
764 | return failure(); |
765 | |
766 | rewriter.replaceOpWithNewOp<memref::DimOp>( |
767 | dimOp, memrefToTensorOp.getMemref(), dimOp.getIndex()); |
768 | return success(); |
769 | } |
770 | }; |
771 | } // namespace |
772 | |
773 | void ToTensorOp::getCanonicalizationPatterns(RewritePatternSet &results, |
774 | MLIRContext *context) { |
775 | results.add<DimOfToTensorFolder>(context); |
776 | } |
777 | |
778 | //===----------------------------------------------------------------------===// |
779 | // ToBufferOp |
780 | //===----------------------------------------------------------------------===// |
781 | |
782 | OpFoldResult ToBufferOp::fold(FoldAdaptor) { |
783 | if (auto memrefToTensor = getTensor().getDefiningOp<ToTensorOp>()) |
784 | if (memrefToTensor.getMemref().getType() == getType()) |
785 | return memrefToTensor.getMemref(); |
786 | return {}; |
787 | } |
788 | |
789 | namespace { |
790 | |
791 | /// Replace tensor.cast + to_buffer by to_buffer + memref.cast. |
792 | struct ToBufferOfCast : public OpRewritePattern<ToBufferOp> { |
793 | using OpRewritePattern<ToBufferOp>::OpRewritePattern; |
794 | |
795 | LogicalResult matchAndRewrite(ToBufferOp toBuffer, |
796 | PatternRewriter &rewriter) const final { |
797 | auto tensorCastOperand = |
798 | toBuffer.getOperand().getDefiningOp<tensor::CastOp>(); |
799 | if (!tensorCastOperand) |
800 | return failure(); |
801 | auto srcTensorType = llvm::dyn_cast<RankedTensorType>( |
802 | tensorCastOperand.getOperand().getType()); |
803 | if (!srcTensorType) |
804 | return failure(); |
805 | auto memrefType = MemRefType::get(srcTensorType.getShape(), |
806 | srcTensorType.getElementType()); |
807 | Value memref = rewriter.create<ToBufferOp>(toBuffer.getLoc(), memrefType, |
808 | tensorCastOperand.getOperand()); |
809 | rewriter.replaceOpWithNewOp<memref::CastOp>(toBuffer, toBuffer.getType(), |
810 | memref); |
811 | return success(); |
812 | } |
813 | }; |
814 | |
815 | /// Canonicalize bufferization.to_tensor + bufferization.to_buffer. Insert a |
816 | /// cast if necessary. |
817 | struct ToBufferToTensorFolding : public OpRewritePattern<ToBufferOp> { |
818 | using OpRewritePattern<ToBufferOp>::OpRewritePattern; |
819 | |
820 | LogicalResult matchAndRewrite(ToBufferOp toBuffer, |
821 | PatternRewriter &rewriter) const final { |
822 | BufferizationOptions options; |
823 | options.bufferAlignment = 0; |
824 | return foldToBufferToTensorPair(rewriter, toBuffer, options); |
825 | } |
826 | }; |
827 | |
828 | /// Fold a load on a to_buffer operation into an tensor.extract on the |
829 | /// corresponding tensor. |
830 | struct LoadOfToBuffer : public OpRewritePattern<memref::LoadOp> { |
831 | using OpRewritePattern<memref::LoadOp>::OpRewritePattern; |
832 | |
833 | LogicalResult matchAndRewrite(memref::LoadOp load, |
834 | PatternRewriter &rewriter) const override { |
835 | auto toBuffer = load.getMemref().getDefiningOp<ToBufferOp>(); |
836 | if (!toBuffer) |
837 | return failure(); |
838 | |
839 | rewriter.replaceOpWithNewOp<tensor::ExtractOp>(load, toBuffer.getTensor(), |
840 | load.getIndices()); |
841 | return success(); |
842 | } |
843 | }; |
844 | |
845 | /// Fold dim of a to_buffer into the dim of the tensor. |
846 | struct DimOfCastOp : public OpRewritePattern<memref::DimOp> { |
847 | using OpRewritePattern<memref::DimOp>::OpRewritePattern; |
848 | |
849 | LogicalResult matchAndRewrite(memref::DimOp dimOp, |
850 | PatternRewriter &rewriter) const override { |
851 | auto castOp = dimOp.getSource().getDefiningOp<ToBufferOp>(); |
852 | if (!castOp) |
853 | return failure(); |
854 | Value newSource = castOp.getOperand(); |
855 | rewriter.replaceOpWithNewOp<tensor::DimOp>(dimOp, newSource, |
856 | dimOp.getIndex()); |
857 | return success(); |
858 | } |
859 | }; |
860 | |
861 | } // namespace |
862 | |
863 | void ToBufferOp::getCanonicalizationPatterns(RewritePatternSet &results, |
864 | MLIRContext *context) { |
865 | results.add<DimOfCastOp, LoadOfToBuffer, ToBufferOfCast, |
866 | ToBufferToTensorFolding>(context); |
867 | } |
868 | |
869 | LogicalResult ToBufferOp::bufferize(RewriterBase &rewriter, |
870 | const BufferizationOptions &options, |
871 | BufferizationState &state) { |
872 | // Fold to_buffer(to_tensor(x)) to x. Insert a cast if necessary. |
873 | (void)foldToBufferToTensorPair(rewriter, *this, options); |
874 | // Note: The return value of `bufferize` indicates whether there was an error |
875 | // or not. (And not whether the pattern matched or not.) |
876 | return success(); |
877 | } |
878 | |
879 | std::optional<Operation *> CloneOp::buildDealloc(OpBuilder &builder, |
880 | Value alloc) { |
881 | return builder.create<memref::DeallocOp>(alloc.getLoc(), alloc) |
882 | .getOperation(); |
883 | } |
884 | |
885 | std::optional<Value> CloneOp::buildClone(OpBuilder &builder, Value alloc) { |
886 | return builder.create<CloneOp>(alloc.getLoc(), alloc).getResult(); |
887 | } |
888 | |
889 | //===----------------------------------------------------------------------===// |
890 | // DeallocOp |
891 | //===----------------------------------------------------------------------===// |
892 | |
893 | LogicalResult DeallocOp::inferReturnTypes( |
894 | MLIRContext *context, std::optional<::mlir::Location> location, |
895 | ValueRange operands, DictionaryAttr attributes, OpaqueProperties properties, |
896 | RegionRange regions, SmallVectorImpl<Type> &inferredReturnTypes) { |
897 | DeallocOpAdaptor adaptor(operands, attributes, properties, regions); |
898 | inferredReturnTypes = SmallVector<Type>(adaptor.getRetained().size(), |
899 | IntegerType::get(context, 1)); |
900 | return success(); |
901 | } |
902 | |
903 | LogicalResult DeallocOp::verify() { |
904 | if (getMemrefs().size() != getConditions().size()) |
905 | return emitOpError( |
906 | "must have the same number of conditions as memrefs to deallocate" ); |
907 | if (getRetained().size() != getUpdatedConditions().size()) |
908 | return emitOpError("must have the same number of updated conditions " |
909 | "(results) as retained operands" ); |
910 | return success(); |
911 | } |
912 | |
913 | static LogicalResult updateDeallocIfChanged(DeallocOp deallocOp, |
914 | ValueRange memrefs, |
915 | ValueRange conditions, |
916 | PatternRewriter &rewriter) { |
917 | if (deallocOp.getMemrefs() == memrefs && |
918 | deallocOp.getConditions() == conditions) |
919 | return failure(); |
920 | |
921 | rewriter.modifyOpInPlace(deallocOp, [&]() { |
922 | deallocOp.getMemrefsMutable().assign(memrefs); |
923 | deallocOp.getConditionsMutable().assign(conditions); |
924 | }); |
925 | return success(); |
926 | } |
927 | |
928 | namespace { |
929 | |
930 | /// Remove duplicate values in the list of memrefs to be deallocated. We need to |
931 | /// make sure the corresponding condition value is updated accordingly since |
932 | /// their two conditions might not cover the same set of cases. In that case, we |
933 | /// have to combine them (by computing the disjunction of them). |
934 | /// Example: |
935 | /// ```mlir |
936 | /// bufferization.dealloc (%arg0, %arg0 : ...) if (%arg1, %arg2) |
937 | /// ``` |
938 | /// is canonicalized to |
939 | /// ```mlir |
940 | /// %0 = arith.ori %arg1, %arg2 : i1 |
941 | /// bufferization.dealloc (%arg0 : memref<2xi32>) if (%0) |
942 | /// ``` |
943 | struct DeallocRemoveDuplicateDeallocMemrefs |
944 | : public OpRewritePattern<DeallocOp> { |
945 | using OpRewritePattern<DeallocOp>::OpRewritePattern; |
946 | |
947 | LogicalResult matchAndRewrite(DeallocOp deallocOp, |
948 | PatternRewriter &rewriter) const override { |
949 | // Unique memrefs to be deallocated. |
950 | DenseMap<Value, unsigned> memrefToCondition; |
951 | SmallVector<Value> newMemrefs, newConditions; |
952 | for (auto [i, memref, cond] : |
953 | llvm::enumerate(deallocOp.getMemrefs(), deallocOp.getConditions())) { |
954 | if (memrefToCondition.count(memref)) { |
955 | // If the dealloc conditions don't match, we need to make sure that the |
956 | // dealloc happens on the union of cases. |
957 | Value &newCond = newConditions[memrefToCondition[memref]]; |
958 | if (newCond != cond) |
959 | newCond = |
960 | rewriter.create<arith::OrIOp>(deallocOp.getLoc(), newCond, cond); |
961 | } else { |
962 | memrefToCondition.insert({memref, newConditions.size()}); |
963 | newMemrefs.push_back(memref); |
964 | newConditions.push_back(cond); |
965 | } |
966 | } |
967 | |
968 | // Return failure if we don't change anything such that we don't run into an |
969 | // infinite loop of pattern applications. |
970 | return updateDeallocIfChanged(deallocOp, newMemrefs, newConditions, |
971 | rewriter); |
972 | } |
973 | }; |
974 | |
975 | /// Remove duplicate values in the list of retained memrefs. We need to make |
976 | /// sure the corresponding result condition value is replaced properly. |
977 | /// Example: |
978 | /// ```mlir |
979 | /// %0:2 = bufferization.dealloc retain (%arg3, %arg3 : ...) |
980 | /// ``` |
981 | /// is canonicalized to |
982 | /// ```mlir |
983 | /// %0 = bufferization.dealloc retain (%arg3 : memref<2xi32>) |
984 | /// ``` |
985 | struct DeallocRemoveDuplicateRetainedMemrefs |
986 | : public OpRewritePattern<DeallocOp> { |
987 | using OpRewritePattern<DeallocOp>::OpRewritePattern; |
988 | |
989 | LogicalResult matchAndRewrite(DeallocOp deallocOp, |
990 | PatternRewriter &rewriter) const override { |
991 | // Unique retained values |
992 | DenseMap<Value, unsigned> seen; |
993 | SmallVector<Value> newRetained; |
994 | SmallVector<unsigned> resultReplacementIdx; |
995 | unsigned i = 0; |
996 | for (auto retained : deallocOp.getRetained()) { |
997 | if (seen.count(retained)) { |
998 | resultReplacementIdx.push_back(seen[retained]); |
999 | continue; |
1000 | } |
1001 | |
1002 | seen[retained] = i; |
1003 | newRetained.push_back(retained); |
1004 | resultReplacementIdx.push_back(i++); |
1005 | } |
1006 | |
1007 | // Return failure if we don't change anything such that we don't run into an |
1008 | // infinite loop of pattern applications. |
1009 | if (newRetained.size() == deallocOp.getRetained().size()) |
1010 | return failure(); |
1011 | |
1012 | // We need to create a new op because the number of results is always the |
1013 | // same as the number of condition operands. |
1014 | auto newDeallocOp = |
1015 | rewriter.create<DeallocOp>(deallocOp.getLoc(), deallocOp.getMemrefs(), |
1016 | deallocOp.getConditions(), newRetained); |
1017 | SmallVector<Value> replacements( |
1018 | llvm::map_range(resultReplacementIdx, [&](unsigned idx) { |
1019 | return newDeallocOp.getUpdatedConditions()[idx]; |
1020 | })); |
1021 | rewriter.replaceOp(deallocOp, replacements); |
1022 | return success(); |
1023 | } |
1024 | }; |
1025 | |
1026 | /// Erase deallocation operations where the variadic list of memrefs to |
1027 | /// deallocate is empty. Example: |
1028 | /// ```mlir |
1029 | /// %0 = bufferization.dealloc retain (%arg0: memref<2xi32>) |
1030 | /// ``` |
1031 | struct EraseEmptyDealloc : public OpRewritePattern<DeallocOp> { |
1032 | using OpRewritePattern<DeallocOp>::OpRewritePattern; |
1033 | |
1034 | LogicalResult matchAndRewrite(DeallocOp deallocOp, |
1035 | PatternRewriter &rewriter) const override { |
1036 | if (deallocOp.getMemrefs().empty()) { |
1037 | Value constFalse = rewriter.create<arith::ConstantOp>( |
1038 | deallocOp.getLoc(), rewriter.getBoolAttr(false)); |
1039 | rewriter.replaceOp( |
1040 | deallocOp, SmallVector<Value>(deallocOp.getUpdatedConditions().size(), |
1041 | constFalse)); |
1042 | return success(); |
1043 | } |
1044 | return failure(); |
1045 | } |
1046 | }; |
1047 | |
1048 | /// Removes memrefs from the deallocation list if their associated condition is |
1049 | /// always 'false'. |
1050 | /// |
1051 | /// Example: |
1052 | /// ``` |
1053 | /// bufferization.dealloc (%arg0, %arg1 : memref<2xi32>, memref<2xi32>) |
1054 | /// if (%arg2, %false) |
1055 | /// ``` |
1056 | /// becomes |
1057 | /// ``` |
1058 | /// bufferization.dealloc (%arg0 : memref<2xi32>) if (%arg2) |
1059 | /// ``` |
1060 | struct EraseAlwaysFalseDealloc : public OpRewritePattern<DeallocOp> { |
1061 | using OpRewritePattern<DeallocOp>::OpRewritePattern; |
1062 | |
1063 | LogicalResult matchAndRewrite(DeallocOp deallocOp, |
1064 | PatternRewriter &rewriter) const override { |
1065 | SmallVector<Value> newMemrefs, newConditions; |
1066 | for (auto [memref, cond] : |
1067 | llvm::zip(deallocOp.getMemrefs(), deallocOp.getConditions())) { |
1068 | if (!matchPattern(cond, m_Zero())) { |
1069 | newMemrefs.push_back(memref); |
1070 | newConditions.push_back(cond); |
1071 | } |
1072 | } |
1073 | |
1074 | return updateDeallocIfChanged(deallocOp, newMemrefs, newConditions, |
1075 | rewriter); |
1076 | } |
1077 | }; |
1078 | |
1079 | /// The `memref.extract_strided_metadata` is often inserted to get the base |
1080 | /// memref if the operand is not already guaranteed to be the result of a memref |
1081 | /// allocation operation. This canonicalization pattern removes this extraction |
1082 | /// operation if the operand is now produced by an allocation operation (e.g., |
1083 | /// due to other canonicalizations simplifying the IR). |
1084 | /// |
1085 | /// Example: |
1086 | /// ```mlir |
1087 | /// %alloc = memref.alloc() : memref<2xi32> |
1088 | /// %base_memref, %offset, %size, %stride = memref.extract_strided_metadata |
1089 | /// %alloc : memref<2xi32> -> memref<i32>, index, index, index |
1090 | /// bufferization.dealloc (%base_memref : memref<i32>) if (%cond) |
1091 | /// ``` |
1092 | /// is canonicalized to |
1093 | /// ```mlir |
1094 | /// %alloc = memref.alloc() : memref<2xi32> |
1095 | /// bufferization.dealloc (%alloc : memref<2xi32>) if (%cond) |
1096 | /// ``` |
1097 | struct : public OpRewritePattern<DeallocOp> { |
1098 | using OpRewritePattern<DeallocOp>::OpRewritePattern; |
1099 | |
1100 | LogicalResult matchAndRewrite(DeallocOp deallocOp, |
1101 | PatternRewriter &rewriter) const override { |
1102 | SmallVector<Value> newMemrefs( |
1103 | llvm::map_range(deallocOp.getMemrefs(), [&](Value memref) { |
1104 | auto = |
1105 | memref.getDefiningOp<memref::ExtractStridedMetadataOp>(); |
1106 | if (!extractStridedOp) |
1107 | return memref; |
1108 | Value allocMemref = extractStridedOp.getOperand(); |
1109 | auto allocOp = allocMemref.getDefiningOp<MemoryEffectOpInterface>(); |
1110 | if (!allocOp) |
1111 | return memref; |
1112 | if (allocOp.getEffectOnValue<MemoryEffects::Allocate>(allocMemref)) |
1113 | return allocMemref; |
1114 | return memref; |
1115 | })); |
1116 | |
1117 | return updateDeallocIfChanged(deallocOp, newMemrefs, |
1118 | deallocOp.getConditions(), rewriter); |
1119 | } |
1120 | }; |
1121 | |
1122 | /// Removes pairs of `bufferization.dealloc` and alloc operations if there is no |
1123 | /// other user of the allocated value and the allocating operation can be safely |
1124 | /// removed. If the same value is present multiple times, this pattern relies on |
1125 | /// other canonicalization patterns to remove the duplicate first. |
1126 | /// |
1127 | /// Example: |
1128 | /// ```mlir |
1129 | /// %alloc = memref.alloc() : memref<2xi32> |
1130 | /// bufferization.dealloc (%alloc, %arg0, : ...) if (%true, %true) |
1131 | /// ``` |
1132 | /// is canonicalized to |
1133 | /// ```mlir |
1134 | /// bufferization.dealloc (%arg0 : ...) if (%true) |
1135 | /// ``` |
1136 | struct RemoveAllocDeallocPairWhenNoOtherUsers |
1137 | : public OpRewritePattern<DeallocOp> { |
1138 | using OpRewritePattern<DeallocOp>::OpRewritePattern; |
1139 | |
1140 | LogicalResult matchAndRewrite(DeallocOp deallocOp, |
1141 | PatternRewriter &rewriter) const override { |
1142 | SmallVector<Value> newMemrefs, newConditions; |
1143 | SmallVector<Operation *> toDelete; |
1144 | for (auto [memref, cond] : |
1145 | llvm::zip(deallocOp.getMemrefs(), deallocOp.getConditions())) { |
1146 | if (auto allocOp = memref.getDefiningOp<MemoryEffectOpInterface>()) { |
1147 | // Check that it is indeed an allocate effect, that the op has no other |
1148 | // side effects (which would not allow us to remove the op), and that |
1149 | // there are no other users. |
1150 | if (allocOp.getEffectOnValue<MemoryEffects::Allocate>(memref) && |
1151 | hasSingleEffect<MemoryEffects::Allocate>(allocOp, memref) && |
1152 | memref.hasOneUse()) { |
1153 | toDelete.push_back(allocOp); |
1154 | continue; |
1155 | } |
1156 | } |
1157 | |
1158 | newMemrefs.push_back(memref); |
1159 | newConditions.push_back(cond); |
1160 | } |
1161 | |
1162 | if (failed(updateDeallocIfChanged(deallocOp, newMemrefs, newConditions, |
1163 | rewriter))) |
1164 | return failure(); |
1165 | |
1166 | for (Operation *op : toDelete) |
1167 | rewriter.eraseOp(op); |
1168 | |
1169 | return success(); |
1170 | } |
1171 | }; |
1172 | |
1173 | } // anonymous namespace |
1174 | |
1175 | void DeallocOp::getCanonicalizationPatterns(RewritePatternSet &results, |
1176 | MLIRContext *context) { |
1177 | populateDeallocOpCanonicalizationPatterns(results, context); |
1178 | } |
1179 | |
1180 | void bufferization::populateDeallocOpCanonicalizationPatterns( |
1181 | RewritePatternSet &patterns, MLIRContext *context) { |
1182 | patterns.add<DeallocRemoveDuplicateDeallocMemrefs, |
1183 | DeallocRemoveDuplicateRetainedMemrefs, EraseEmptyDealloc, |
1184 | EraseAlwaysFalseDealloc, SkipExtractMetadataOfAlloc, |
1185 | RemoveAllocDeallocPairWhenNoOtherUsers>(arg&: context); |
1186 | } |
1187 | |
1188 | //===----------------------------------------------------------------------===// |
1189 | // TableGen'd op method definitions |
1190 | //===----------------------------------------------------------------------===// |
1191 | |
1192 | #define GET_OP_CLASSES |
1193 | #include "mlir/Dialect/Bufferization/IR/BufferizationOps.cpp.inc" |
1194 | |