1 //===- GPUDialect.cpp - MLIR Dialect for GPU Kernels implementation -------===//
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 GPU kernel-related dialect and its operations.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "mlir/Dialect/GPU/GPUDialect.h"
14 
15 #include "mlir/Dialect/Arithmetic/IR/Arithmetic.h"
16 #include "mlir/Dialect/MemRef/IR/MemRef.h"
17 #include "mlir/IR/Attributes.h"
18 #include "mlir/IR/Builders.h"
19 #include "mlir/IR/BuiltinOps.h"
20 #include "mlir/IR/BuiltinTypes.h"
21 #include "mlir/IR/DialectImplementation.h"
22 #include "mlir/IR/FunctionImplementation.h"
23 #include "mlir/IR/Matchers.h"
24 #include "mlir/IR/OpImplementation.h"
25 #include "mlir/IR/PatternMatch.h"
26 #include "mlir/IR/TypeUtilities.h"
27 #include "mlir/Transforms/InliningUtils.h"
28 #include "llvm/ADT/TypeSwitch.h"
29 
30 using namespace mlir;
31 using namespace mlir::gpu;
32 
33 #include "mlir/Dialect/GPU/GPUOpsDialect.cpp.inc"
34 
35 //===----------------------------------------------------------------------===//
36 // MMAMatrixType
37 //===----------------------------------------------------------------------===//
38 
39 MMAMatrixType MMAMatrixType::get(ArrayRef<int64_t> shape, Type elementType,
40                                  StringRef operand) {
41   return Base::get(elementType.getContext(), shape, elementType, operand);
42 }
43 
44 MMAMatrixType
45 MMAMatrixType::getChecked(function_ref<InFlightDiagnostic()> emitError,
46                           ArrayRef<int64_t> shape, Type elementType,
47                           StringRef operand) {
48   return Base::getChecked(emitError, elementType.getContext(), shape,
49                           elementType, operand);
50 }
51 
52 unsigned MMAMatrixType::getNumDims() const { return getImpl()->numDims; }
53 
54 ArrayRef<int64_t> MMAMatrixType::getShape() const {
55   return getImpl()->getShape();
56 }
57 
58 Type MMAMatrixType::getElementType() const { return getImpl()->elementType; }
59 
60 StringRef MMAMatrixType::getOperand() const { return getImpl()->getOperand(); }
61 
62 bool MMAMatrixType::isValidElementType(Type elementType) {
63   return elementType.isF16() || elementType.isF32();
64 }
65 
66 LogicalResult
67 MMAMatrixType::verify(function_ref<InFlightDiagnostic()> emitError,
68                       ArrayRef<int64_t> shape, Type elementType,
69                       StringRef operand) {
70   if (!operand.equals("AOp") && !operand.equals("BOp") &&
71       !operand.equals("COp"))
72     return emitError() << "operand expected to be one of AOp, BOp or COp";
73 
74   if (shape.size() != 2)
75     return emitError() << "MMAMatrixType must have exactly two dimensions";
76 
77   if (!MMAMatrixType::isValidElementType(elementType))
78     return emitError() << "MMAMatrixType elements must be F16 or F32";
79 
80   return success();
81 }
82 
83 //===----------------------------------------------------------------------===//
84 // GPUDialect
85 //===----------------------------------------------------------------------===//
86 
87 /// GPU memory space identifiers.
88 enum GPUMemorySpace {
89   /// Generic memory space identifier.
90   kGenericMemorySpace = 0,
91 
92   /// Global memory space identifier.
93   kGlobalMemorySpace = 1,
94 
95   /// Shared memory space identifier.
96   kSharedMemorySpace = 3
97 };
98 
99 bool GPUDialect::isKernel(Operation *op) {
100   UnitAttr isKernelAttr = op->getAttrOfType<UnitAttr>(getKernelFuncAttrName());
101   return static_cast<bool>(isKernelAttr);
102 }
103 
104 namespace {
105 /// This class defines the interface for handling inlining with gpu
106 /// operations.
107 struct GPUInlinerInterface : public DialectInlinerInterface {
108   using DialectInlinerInterface::DialectInlinerInterface;
109 
110   /// All gpu dialect ops can be inlined.
111   bool isLegalToInline(Operation *, Region *, bool,
112                        BlockAndValueMapping &) const final {
113     return true;
114   }
115 };
116 } // namespace
117 
118 void GPUDialect::initialize() {
119   addTypes<AsyncTokenType>();
120   addTypes<MMAMatrixType>();
121   addOperations<
122 #define GET_OP_LIST
123 #include "mlir/Dialect/GPU/GPUOps.cpp.inc"
124       >();
125   addAttributes<
126 #define GET_ATTRDEF_LIST
127 #include "mlir/Dialect/GPU/GPUOpsAttributes.cpp.inc"
128       >();
129   addInterfaces<GPUInlinerInterface>();
130 }
131 
132 Type GPUDialect::parseType(DialectAsmParser &parser) const {
133   // Parse the main keyword for the type.
134   StringRef keyword;
135   if (parser.parseKeyword(&keyword))
136     return Type();
137   MLIRContext *context = getContext();
138 
139   // Handle 'async token' types.
140   if (keyword == "async.token")
141     return AsyncTokenType::get(context);
142 
143   if (keyword == "mma_matrix") {
144     SMLoc beginLoc = parser.getNameLoc();
145 
146     // Parse '<'.
147     if (parser.parseLess())
148       return nullptr;
149 
150     // Parse the size and elementType.
151     SmallVector<int64_t> shape;
152     Type elementType;
153     if (parser.parseDimensionList(shape, /*allowDynamic=*/false) ||
154         parser.parseType(elementType))
155       return nullptr;
156 
157     // Parse ','
158     if (parser.parseComma())
159       return nullptr;
160 
161     // Parse operand.
162     std::string operand;
163     if (failed(parser.parseOptionalString(&operand)))
164       return nullptr;
165 
166     // Parse '>'.
167     if (parser.parseGreater())
168       return nullptr;
169 
170     return MMAMatrixType::getChecked(mlir::detail::getDefaultDiagnosticEmitFn(
171                                          parser.getEncodedSourceLoc(beginLoc)),
172                                      shape, elementType, operand);
173   }
174 
175   parser.emitError(parser.getNameLoc(), "unknown gpu type: " + keyword);
176   return Type();
177 }
178 
179 void GPUDialect::printType(Type type, DialectAsmPrinter &os) const {
180   TypeSwitch<Type>(type)
181       .Case<AsyncTokenType>([&](Type) { os << "async.token"; })
182       .Case<MMAMatrixType>([&](MMAMatrixType fragTy) {
183         os << "mma_matrix<";
184         auto shape = fragTy.getShape();
185         for (auto dim = shape.begin(), e = shape.end() - 1; dim != e; ++dim)
186           os << *dim << 'x';
187         os << shape.back() << 'x' << fragTy.getElementType();
188         os << ", \"" << fragTy.getOperand() << "\"" << '>';
189       })
190       .Default([](Type) { llvm_unreachable("unexpected 'gpu' type kind"); });
191 }
192 
193 LogicalResult GPUDialect::verifyOperationAttribute(Operation *op,
194                                                    NamedAttribute attr) {
195   if (!attr.getValue().isa<UnitAttr>() ||
196       attr.getName() != getContainerModuleAttrName())
197     return success();
198 
199   auto module = dyn_cast<ModuleOp>(op);
200   if (!module)
201     return op->emitError("expected '")
202            << getContainerModuleAttrName() << "' attribute to be attached to '"
203            << ModuleOp::getOperationName() << '\'';
204 
205   auto walkResult = module.walk([&module](LaunchFuncOp launchOp) -> WalkResult {
206     // Ignore launches that are nested more or less deep than functions in the
207     // module we are currently checking.
208     if (!launchOp->getParentOp() ||
209         launchOp->getParentOp()->getParentOp() != module)
210       return success();
211 
212     // Ignore launch ops with missing attributes here. The errors will be
213     // reported by the verifiers of those ops.
214     if (!launchOp->getAttrOfType<SymbolRefAttr>(
215             LaunchFuncOp::getKernelAttrName()))
216       return success();
217 
218     // Check that `launch_func` refers to a well-formed GPU kernel module.
219     StringAttr kernelModuleName = launchOp.getKernelModuleName();
220     auto kernelModule = module.lookupSymbol<GPUModuleOp>(kernelModuleName);
221     if (!kernelModule)
222       return launchOp.emitOpError()
223              << "kernel module '" << kernelModuleName.getValue()
224              << "' is undefined";
225 
226     // Check that `launch_func` refers to a well-formed kernel function.
227     Operation *kernelFunc = module.lookupSymbol(launchOp.kernelAttr());
228     if (!kernelFunc)
229       return launchOp.emitOpError("kernel function '")
230              << launchOp.kernel() << "' is undefined";
231     auto kernelConvertedFunction = dyn_cast<FunctionOpInterface>(kernelFunc);
232     if (!kernelConvertedFunction) {
233       InFlightDiagnostic diag = launchOp.emitOpError()
234                                 << "referenced kernel '" << launchOp.kernel()
235                                 << "' is not a function";
236       diag.attachNote(kernelFunc->getLoc()) << "see the kernel definition here";
237       return diag;
238     }
239 
240     if (!kernelFunc->getAttrOfType<mlir::UnitAttr>(
241             GPUDialect::getKernelFuncAttrName()))
242       return launchOp.emitOpError("kernel function is missing the '")
243              << GPUDialect::getKernelFuncAttrName() << "' attribute";
244 
245     // TODO: If the kernel isn't a GPU function (which happens during separate
246     // compilation), do not check type correspondence as it would require the
247     // verifier to be aware of the type conversion.
248     auto kernelGPUFunction = dyn_cast<gpu::GPUFuncOp>(kernelFunc);
249     if (!kernelGPUFunction)
250       return success();
251 
252     unsigned actualNumArguments = launchOp.getNumKernelOperands();
253     unsigned expectedNumArguments = kernelGPUFunction.getNumArguments();
254     if (expectedNumArguments != actualNumArguments)
255       return launchOp.emitOpError("got ")
256              << actualNumArguments << " kernel operands but expected "
257              << expectedNumArguments;
258 
259     auto functionType = kernelGPUFunction.getType();
260     for (unsigned i = 0; i < expectedNumArguments; ++i) {
261       if (launchOp.getKernelOperand(i).getType() != functionType.getInput(i)) {
262         return launchOp.emitOpError("type of function argument ")
263                << i << " does not match";
264       }
265     }
266 
267     return success();
268   });
269 
270   return walkResult.wasInterrupted() ? failure() : success();
271 }
272 
273 template <typename T>
274 static LogicalResult verifyIndexOp(T op) {
275   auto dimension = op.dimension();
276   if (dimension != "x" && dimension != "y" && dimension != "z")
277     return op.emitError("dimension \"") << dimension << "\" is invalid";
278   return success();
279 }
280 
281 static LogicalResult verifyAllReduce(gpu::AllReduceOp allReduce) {
282   if (allReduce.body().empty() != allReduce.op().hasValue())
283     return allReduce.emitError(
284         "expected either an op attribute or a non-empty body");
285   if (!allReduce.body().empty()) {
286     if (allReduce.body().getNumArguments() != 2)
287       return allReduce.emitError("expected two region arguments");
288     for (auto argument : allReduce.body().getArguments()) {
289       if (argument.getType() != allReduce.getType())
290         return allReduce.emitError("incorrect region argument type");
291     }
292     unsigned yieldCount = 0;
293     for (Block &block : allReduce.body()) {
294       if (auto yield = dyn_cast<gpu::YieldOp>(block.getTerminator())) {
295         if (yield.getNumOperands() != 1)
296           return allReduce.emitError("expected one gpu.yield operand");
297         if (yield.getOperand(0).getType() != allReduce.getType())
298           return allReduce.emitError("incorrect gpu.yield type");
299         ++yieldCount;
300       }
301     }
302     if (yieldCount == 0)
303       return allReduce.emitError("expected gpu.yield op in region");
304   } else {
305     gpu::AllReduceOperation opName = *allReduce.op();
306     if ((opName == gpu::AllReduceOperation::AND ||
307          opName == gpu::AllReduceOperation::OR ||
308          opName == gpu::AllReduceOperation::XOR) &&
309         !allReduce.getType().isa<IntegerType>()) {
310       return allReduce.emitError()
311              << '`' << gpu::stringifyAllReduceOperation(opName) << '`'
312              << " accumulator is only compatible with Integer type";
313     }
314   }
315   return success();
316 }
317 
318 // TODO: Support optional custom attributes (without dialect prefix).
319 static ParseResult parseAllReduceOperation(AsmParser &parser,
320                                            AllReduceOperationAttr &attr) {
321   StringRef enumStr;
322   if (!parser.parseOptionalKeyword(&enumStr)) {
323     Optional<AllReduceOperation> op = gpu::symbolizeAllReduceOperation(enumStr);
324     if (!op)
325       return parser.emitError(parser.getCurrentLocation(), "invalid op kind");
326     attr = AllReduceOperationAttr::get(parser.getContext(), *op);
327   }
328   return success();
329 }
330 
331 static void printAllReduceOperation(AsmPrinter &printer, Operation *op,
332                                     AllReduceOperationAttr attr) {
333   if (attr)
334     attr.print(printer);
335 }
336 
337 //===----------------------------------------------------------------------===//
338 // AsyncOpInterface
339 //===----------------------------------------------------------------------===//
340 
341 void gpu::addAsyncDependency(Operation *op, Value token) {
342   op->insertOperands(0, {token});
343   if (!op->template hasTrait<OpTrait::AttrSizedOperandSegments>())
344     return;
345   auto attrName =
346       OpTrait::AttrSizedOperandSegments<void>::getOperandSegmentSizeAttr();
347   auto sizeAttr = op->template getAttrOfType<DenseIntElementsAttr>(attrName);
348 
349   // Async dependencies is the only variadic operand.
350   if (!sizeAttr)
351     return;
352 
353   SmallVector<int32_t, 8> sizes(sizeAttr.getValues<int32_t>());
354   ++sizes.front();
355   op->setAttr(attrName, Builder(op->getContext()).getI32VectorAttr(sizes));
356 }
357 
358 //===----------------------------------------------------------------------===//
359 // LaunchOp
360 //===----------------------------------------------------------------------===//
361 
362 void LaunchOp::build(OpBuilder &builder, OperationState &result,
363                      Value gridSizeX, Value gridSizeY, Value gridSizeZ,
364                      Value blockSizeX, Value blockSizeY, Value blockSizeZ,
365                      Value dynamicSharedMemorySize) {
366   // Add grid and block sizes as op operands, followed by the data operands.
367   result.addOperands(
368       {gridSizeX, gridSizeY, gridSizeZ, blockSizeX, blockSizeY, blockSizeZ});
369   if (dynamicSharedMemorySize)
370     result.addOperands(dynamicSharedMemorySize);
371 
372   // Create a kernel body region with kNumConfigRegionAttributes + N arguments,
373   // where the first kNumConfigRegionAttributes arguments have `index` type and
374   // the rest have the same types as the data operands.
375   Region *kernelRegion = result.addRegion();
376   Block *body = new Block();
377   for (unsigned i = 0; i < kNumConfigRegionAttributes; ++i)
378     body->addArgument(builder.getIndexType(), result.location);
379   kernelRegion->push_back(body);
380 }
381 
382 KernelDim3 LaunchOp::getBlockIds() {
383   assert(!body().empty() && "LaunchOp body must not be empty.");
384   auto args = body().getArguments();
385   return KernelDim3{args[0], args[1], args[2]};
386 }
387 
388 KernelDim3 LaunchOp::getThreadIds() {
389   assert(!body().empty() && "LaunchOp body must not be empty.");
390   auto args = body().getArguments();
391   return KernelDim3{args[3], args[4], args[5]};
392 }
393 
394 KernelDim3 LaunchOp::getGridSize() {
395   assert(!body().empty() && "LaunchOp body must not be empty.");
396   auto args = body().getArguments();
397   return KernelDim3{args[6], args[7], args[8]};
398 }
399 
400 KernelDim3 LaunchOp::getBlockSize() {
401   assert(!body().empty() && "LaunchOp body must not be empty.");
402   auto args = body().getArguments();
403   return KernelDim3{args[9], args[10], args[11]};
404 }
405 
406 KernelDim3 LaunchOp::getGridSizeOperandValues() {
407   return KernelDim3{getOperand(0), getOperand(1), getOperand(2)};
408 }
409 
410 KernelDim3 LaunchOp::getBlockSizeOperandValues() {
411   return KernelDim3{getOperand(3), getOperand(4), getOperand(5)};
412 }
413 
414 static LogicalResult verify(LaunchOp op) {
415   // Kernel launch takes kNumConfigOperands leading operands for grid/block
416   // sizes and transforms them into kNumConfigRegionAttributes region arguments
417   // for block/thread identifiers and grid/block sizes.
418   if (!op.body().empty()) {
419     if (op.body().getNumArguments() !=
420         LaunchOp::kNumConfigOperands + op.getNumOperands() -
421             (op.dynamicSharedMemorySize() ? 1 : 0))
422       return op.emitOpError("unexpected number of region arguments");
423   }
424 
425   // Block terminators without successors are expected to exit the kernel region
426   // and must be `gpu.terminator`.
427   for (Block &block : op.body()) {
428     if (block.empty())
429       continue;
430     if (block.back().getNumSuccessors() != 0)
431       continue;
432     if (!isa<gpu::TerminatorOp>(&block.back())) {
433       return block.back()
434           .emitError()
435           .append("expected '", gpu::TerminatorOp::getOperationName(),
436                   "' or a terminator with successors")
437           .attachNote(op.getLoc())
438           .append("in '", LaunchOp::getOperationName(), "' body region");
439     }
440   }
441 
442   return success();
443 }
444 
445 // Pretty-print the kernel grid/block size assignment as
446 //   (%iter-x, %iter-y, %iter-z) in
447 //   (%size-x = %ssa-use, %size-y = %ssa-use, %size-z = %ssa-use)
448 // where %size-* and %iter-* will correspond to the body region arguments.
449 static void printSizeAssignment(OpAsmPrinter &p, KernelDim3 size,
450                                 KernelDim3 operands, KernelDim3 ids) {
451   p << '(' << ids.x << ", " << ids.y << ", " << ids.z << ") in (";
452   p << size.x << " = " << operands.x << ", ";
453   p << size.y << " = " << operands.y << ", ";
454   p << size.z << " = " << operands.z << ')';
455 }
456 
457 static void printLaunchOp(OpAsmPrinter &p, LaunchOp op) {
458   // Print the launch configuration.
459   p << ' ' << op.getBlocksKeyword();
460   printSizeAssignment(p, op.getGridSize(), op.getGridSizeOperandValues(),
461                       op.getBlockIds());
462   p << ' ' << op.getThreadsKeyword();
463   printSizeAssignment(p, op.getBlockSize(), op.getBlockSizeOperandValues(),
464                       op.getThreadIds());
465   if (op.dynamicSharedMemorySize())
466     p << ' ' << op.getDynamicSharedMemorySizeKeyword() << ' '
467       << op.dynamicSharedMemorySize();
468 
469   p << ' ';
470   p.printRegion(op.body(), /*printEntryBlockArgs=*/false);
471   p.printOptionalAttrDict(op->getAttrs());
472 }
473 
474 // Parse the size assignment blocks for blocks and threads.  These have the form
475 //   (%region_arg, %region_arg, %region_arg) in
476 //   (%region_arg = %operand, %region_arg = %operand, %region_arg = %operand)
477 // where %region_arg are percent-identifiers for the region arguments to be
478 // introduced further (SSA defs), and %operand are percent-identifiers for the
479 // SSA value uses.
480 static ParseResult
481 parseSizeAssignment(OpAsmParser &parser,
482                     MutableArrayRef<OpAsmParser::OperandType> sizes,
483                     MutableArrayRef<OpAsmParser::OperandType> regionSizes,
484                     MutableArrayRef<OpAsmParser::OperandType> indices) {
485   assert(indices.size() == 3 && "space for three indices expected");
486   SmallVector<OpAsmParser::OperandType, 3> args;
487   if (parser.parseRegionArgumentList(args, /*requiredOperandCount=*/3,
488                                      OpAsmParser::Delimiter::Paren) ||
489       parser.parseKeyword("in") || parser.parseLParen())
490     return failure();
491   std::move(args.begin(), args.end(), indices.begin());
492 
493   for (int i = 0; i < 3; ++i) {
494     if (i != 0 && parser.parseComma())
495       return failure();
496     if (parser.parseRegionArgument(regionSizes[i]) || parser.parseEqual() ||
497         parser.parseOperand(sizes[i]))
498       return failure();
499   }
500 
501   return parser.parseRParen();
502 }
503 
504 // Parses a Launch operation.
505 // operation ::= `gpu.launch` `blocks` `(` ssa-id-list `)` `in` ssa-reassignment
506 //                           `threads` `(` ssa-id-list `)` `in` ssa-reassignment
507 //                            region attr-dict?
508 // ssa-reassignment ::= `(` ssa-id `=` ssa-use (`,` ssa-id `=` ssa-use)* `)`
509 static ParseResult parseLaunchOp(OpAsmParser &parser, OperationState &result) {
510   // Sizes of the grid and block.
511   SmallVector<OpAsmParser::OperandType, LaunchOp::kNumConfigOperands> sizes(
512       LaunchOp::kNumConfigOperands);
513   MutableArrayRef<OpAsmParser::OperandType> sizesRef(sizes);
514 
515   // Actual (data) operands passed to the kernel.
516   SmallVector<OpAsmParser::OperandType, 4> dataOperands;
517 
518   // Region arguments to be created.
519   SmallVector<OpAsmParser::OperandType, 16> regionArgs(
520       LaunchOp::kNumConfigRegionAttributes);
521   MutableArrayRef<OpAsmParser::OperandType> regionArgsRef(regionArgs);
522 
523   // Parse the size assignment segments: the first segment assigns grid sizes
524   // and defines values for block identifiers; the second segment assigns block
525   // sizes and defines values for thread identifiers.  In the region argument
526   // list, identifiers precede sizes, and block-related values precede
527   // thread-related values.
528   if (parser.parseKeyword(LaunchOp::getBlocksKeyword().data()) ||
529       parseSizeAssignment(parser, sizesRef.take_front(3),
530                           regionArgsRef.slice(6, 3),
531                           regionArgsRef.slice(0, 3)) ||
532       parser.parseKeyword(LaunchOp::getThreadsKeyword().data()) ||
533       parseSizeAssignment(parser, sizesRef.drop_front(3),
534                           regionArgsRef.slice(9, 3),
535                           regionArgsRef.slice(3, 3)) ||
536       parser.resolveOperands(sizes, parser.getBuilder().getIndexType(),
537                              result.operands))
538     return failure();
539 
540   OpAsmParser::OperandType dynamicSharedMemorySize;
541   if (!parser.parseOptionalKeyword(
542           LaunchOp::getDynamicSharedMemorySizeKeyword()))
543     if (parser.parseOperand(dynamicSharedMemorySize) ||
544         parser.resolveOperand(dynamicSharedMemorySize,
545                               parser.getBuilder().getI32Type(),
546                               result.operands))
547       return failure();
548 
549   // Introduce the body region and parse it. The region has
550   // kNumConfigRegionAttributes arguments that correspond to
551   // block/thread identifiers and grid/block sizes, all of the `index` type.
552   Type index = parser.getBuilder().getIndexType();
553   SmallVector<Type, LaunchOp::kNumConfigRegionAttributes> dataTypes(
554       LaunchOp::kNumConfigRegionAttributes, index);
555   Region *body = result.addRegion();
556   return failure(parser.parseRegion(*body, regionArgs, dataTypes) ||
557                  parser.parseOptionalAttrDict(result.attributes));
558 }
559 
560 /// Simplify the gpu.launch when the range of a thread or block ID is
561 /// trivially known to be one.
562 struct FoldLaunchArguments : public OpRewritePattern<LaunchOp> {
563   using OpRewritePattern<LaunchOp>::OpRewritePattern;
564   LogicalResult matchAndRewrite(LaunchOp op,
565                                 PatternRewriter &rewriter) const override {
566     // If the range implies a single value for `id`, replace `id`'s uses by
567     // zero.
568     Value zero;
569     bool simplified = false;
570     auto constPropIdUses = [&](Value id, Value size) {
571       // Check if size is trivially one.
572       if (!matchPattern(size, m_One()))
573         return;
574       if (!simplified) {
575         // Create a zero value the first time.
576         OpBuilder::InsertionGuard guard(rewriter);
577         rewriter.setInsertionPointToStart(&op.body().front());
578         zero =
579             rewriter.create<arith::ConstantIndexOp>(op.getLoc(), /*value=*/0);
580       }
581       id.replaceAllUsesWith(zero);
582       simplified = true;
583     };
584     constPropIdUses(op.getBlockIds().x, op.gridSizeX());
585     constPropIdUses(op.getBlockIds().y, op.gridSizeY());
586     constPropIdUses(op.getBlockIds().z, op.gridSizeZ());
587     constPropIdUses(op.getThreadIds().x, op.blockSizeX());
588     constPropIdUses(op.getThreadIds().y, op.blockSizeY());
589     constPropIdUses(op.getThreadIds().z, op.blockSizeZ());
590 
591     return success(simplified);
592   }
593 };
594 
595 void LaunchOp::getCanonicalizationPatterns(RewritePatternSet &rewrites,
596                                            MLIRContext *context) {
597   rewrites.add<FoldLaunchArguments>(context);
598 }
599 
600 //===----------------------------------------------------------------------===//
601 // LaunchFuncOp
602 //===----------------------------------------------------------------------===//
603 
604 void LaunchFuncOp::build(OpBuilder &builder, OperationState &result,
605                          GPUFuncOp kernelFunc, KernelDim3 gridSize,
606                          KernelDim3 blockSize, Value dynamicSharedMemorySize,
607                          ValueRange kernelOperands) {
608   // Add grid and block sizes as op operands, followed by the data operands.
609   result.addOperands({gridSize.x, gridSize.y, gridSize.z, blockSize.x,
610                       blockSize.y, blockSize.z});
611   if (dynamicSharedMemorySize)
612     result.addOperands(dynamicSharedMemorySize);
613   result.addOperands(kernelOperands);
614   auto kernelModule = kernelFunc->getParentOfType<GPUModuleOp>();
615   auto kernelSymbol =
616       SymbolRefAttr::get(kernelModule.getNameAttr(),
617                          {SymbolRefAttr::get(kernelFunc.getNameAttr())});
618   result.addAttribute(getKernelAttrName(), kernelSymbol);
619   SmallVector<int32_t, 9> segmentSizes(9, 1);
620   segmentSizes.front() = 0; // Initially no async dependencies.
621   segmentSizes[segmentSizes.size() - 2] = dynamicSharedMemorySize ? 1 : 0;
622   segmentSizes.back() = static_cast<int32_t>(kernelOperands.size());
623   result.addAttribute(getOperandSegmentSizeAttr(),
624                       builder.getI32VectorAttr(segmentSizes));
625 }
626 
627 unsigned LaunchFuncOp::getNumKernelOperands() {
628   return getNumOperands() - asyncDependencies().size() - kNumConfigOperands -
629          (dynamicSharedMemorySize() ? 1 : 0);
630 }
631 
632 StringAttr LaunchFuncOp::getKernelModuleName() {
633   return kernel().getRootReference();
634 }
635 
636 StringAttr LaunchFuncOp::getKernelName() { return kernel().getLeafReference(); }
637 
638 Value LaunchFuncOp::getKernelOperand(unsigned i) {
639   return getOperand(asyncDependencies().size() + kNumConfigOperands +
640                     (dynamicSharedMemorySize() ? 1 : 0) + i);
641 }
642 
643 KernelDim3 LaunchFuncOp::getGridSizeOperandValues() {
644   auto operands = getOperands().drop_front(asyncDependencies().size());
645   return KernelDim3{operands[0], operands[1], operands[2]};
646 }
647 
648 KernelDim3 LaunchFuncOp::getBlockSizeOperandValues() {
649   auto operands = getOperands().drop_front(asyncDependencies().size());
650   return KernelDim3{operands[3], operands[4], operands[5]};
651 }
652 
653 static LogicalResult verify(LaunchFuncOp op) {
654   auto module = op->getParentOfType<ModuleOp>();
655   if (!module)
656     return op.emitOpError("expected to belong to a module");
657 
658   if (!module->getAttrOfType<UnitAttr>(
659           GPUDialect::getContainerModuleAttrName()))
660     return op.emitOpError(
661         "expected the closest surrounding module to have the '" +
662         GPUDialect::getContainerModuleAttrName() + "' attribute");
663 
664   auto kernelAttr = op->getAttrOfType<SymbolRefAttr>(op.getKernelAttrName());
665   if (!kernelAttr)
666     return op.emitOpError("symbol reference attribute '" +
667                           op.getKernelAttrName() + "' must be specified");
668 
669   return success();
670 }
671 
672 static ParseResult
673 parseLaunchFuncOperands(OpAsmParser &parser,
674                         SmallVectorImpl<OpAsmParser::OperandType> &argNames,
675                         SmallVectorImpl<Type> &argTypes) {
676   if (parser.parseOptionalKeyword("args"))
677     return success();
678   SmallVector<NamedAttrList> argAttrs;
679   SmallVector<Location> argLocations;
680   bool isVariadic = false;
681   return function_interface_impl::parseFunctionArgumentList(
682       parser, /*allowAttributes=*/false,
683       /*allowVariadic=*/false, argNames, argTypes, argAttrs, argLocations,
684       isVariadic);
685 }
686 
687 static void printLaunchFuncOperands(OpAsmPrinter &printer, Operation *,
688                                     OperandRange operands, TypeRange types) {
689   if (operands.empty())
690     return;
691   printer << "args(";
692   llvm::interleaveComma(llvm::zip(operands, types), printer,
693                         [&](const auto &pair) {
694                           printer.printOperand(std::get<0>(pair));
695                           printer << " : ";
696                           printer.printType(std::get<1>(pair));
697                         });
698   printer << ")";
699 }
700 
701 //===----------------------------------------------------------------------===//
702 // GPUFuncOp
703 //===----------------------------------------------------------------------===//
704 
705 /// Adds a new block argument that corresponds to buffers located in
706 /// workgroup memory.
707 BlockArgument GPUFuncOp::addWorkgroupAttribution(Type type, Location loc) {
708   auto attrName = getNumWorkgroupAttributionsAttrName();
709   auto attr = (*this)->getAttrOfType<IntegerAttr>(attrName);
710   (*this)->setAttr(attrName,
711                    IntegerAttr::get(attr.getType(), attr.getValue() + 1));
712   return getBody().insertArgument(getType().getNumInputs() + attr.getInt(),
713                                   type, loc);
714 }
715 
716 /// Adds a new block argument that corresponds to buffers located in
717 /// private memory.
718 BlockArgument GPUFuncOp::addPrivateAttribution(Type type, Location loc) {
719   // Buffers on the private memory always come after buffers on the workgroup
720   // memory.
721   return getBody().addArgument(type, loc);
722 }
723 
724 void GPUFuncOp::build(OpBuilder &builder, OperationState &result,
725                       StringRef name, FunctionType type,
726                       TypeRange workgroupAttributions,
727                       TypeRange privateAttributions,
728                       ArrayRef<NamedAttribute> attrs) {
729   result.addAttribute(SymbolTable::getSymbolAttrName(),
730                       builder.getStringAttr(name));
731   result.addAttribute(getTypeAttrName(), TypeAttr::get(type));
732   result.addAttribute(getNumWorkgroupAttributionsAttrName(),
733                       builder.getI64IntegerAttr(workgroupAttributions.size()));
734   result.addAttributes(attrs);
735   Region *body = result.addRegion();
736   Block *entryBlock = new Block;
737 
738   // TODO: Allow passing in proper locations here.
739   for (Type argTy : type.getInputs())
740     entryBlock->addArgument(argTy, result.location);
741   for (Type argTy : workgroupAttributions)
742     entryBlock->addArgument(argTy, result.location);
743   for (Type argTy : privateAttributions)
744     entryBlock->addArgument(argTy, result.location);
745 
746   body->getBlocks().push_back(entryBlock);
747 }
748 
749 /// Parses a GPU function memory attribution.
750 ///
751 /// memory-attribution ::= (`workgroup` `(` ssa-id-and-type-list `)`)?
752 ///                        (`private` `(` ssa-id-and-type-list `)`)?
753 ///
754 /// Note that this function parses only one of the two similar parts, with the
755 /// keyword provided as argument.
756 static ParseResult
757 parseAttributions(OpAsmParser &parser, StringRef keyword,
758                   SmallVectorImpl<OpAsmParser::OperandType> &args,
759                   SmallVectorImpl<Type> &argTypes) {
760   // If we could not parse the keyword, just assume empty list and succeed.
761   if (failed(parser.parseOptionalKeyword(keyword)))
762     return success();
763 
764   if (failed(parser.parseLParen()))
765     return failure();
766 
767   // Early exit for an empty list.
768   if (succeeded(parser.parseOptionalRParen()))
769     return success();
770 
771   do {
772     OpAsmParser::OperandType arg;
773     Type type;
774 
775     if (parser.parseRegionArgument(arg) || parser.parseColonType(type))
776       return failure();
777 
778     args.push_back(arg);
779     argTypes.push_back(type);
780   } while (succeeded(parser.parseOptionalComma()));
781 
782   return parser.parseRParen();
783 }
784 
785 /// Parses a GPU function.
786 ///
787 /// <operation> ::= `gpu.func` symbol-ref-id `(` argument-list `)`
788 ///                 (`->` function-result-list)? memory-attribution `kernel`?
789 ///                 function-attributes? region
790 static ParseResult parseGPUFuncOp(OpAsmParser &parser, OperationState &result) {
791   SmallVector<OpAsmParser::OperandType> entryArgs;
792   SmallVector<NamedAttrList> argAttrs;
793   SmallVector<NamedAttrList> resultAttrs;
794   SmallVector<Type> argTypes;
795   SmallVector<Type> resultTypes;
796   SmallVector<Location> argLocations;
797   bool isVariadic;
798 
799   // Parse the function name.
800   StringAttr nameAttr;
801   if (parser.parseSymbolName(nameAttr, ::mlir::SymbolTable::getSymbolAttrName(),
802                              result.attributes))
803     return failure();
804 
805   auto signatureLocation = parser.getCurrentLocation();
806   if (failed(function_interface_impl::parseFunctionSignature(
807           parser, /*allowVariadic=*/false, entryArgs, argTypes, argAttrs,
808           argLocations, isVariadic, resultTypes, resultAttrs)))
809     return failure();
810 
811   if (entryArgs.empty() && !argTypes.empty())
812     return parser.emitError(signatureLocation)
813            << "gpu.func requires named arguments";
814 
815   // Construct the function type. More types will be added to the region, but
816   // not to the function type.
817   Builder &builder = parser.getBuilder();
818   auto type = builder.getFunctionType(argTypes, resultTypes);
819   result.addAttribute(GPUFuncOp::getTypeAttrName(), TypeAttr::get(type));
820 
821   // Parse workgroup memory attributions.
822   if (failed(parseAttributions(parser, GPUFuncOp::getWorkgroupKeyword(),
823                                entryArgs, argTypes)))
824     return failure();
825 
826   // Store the number of operands we just parsed as the number of workgroup
827   // memory attributions.
828   unsigned numWorkgroupAttrs = argTypes.size() - type.getNumInputs();
829   result.addAttribute(GPUFuncOp::getNumWorkgroupAttributionsAttrName(),
830                       builder.getI64IntegerAttr(numWorkgroupAttrs));
831 
832   // Parse private memory attributions.
833   if (failed(parseAttributions(parser, GPUFuncOp::getPrivateKeyword(),
834                                entryArgs, argTypes)))
835     return failure();
836 
837   // Parse the kernel attribute if present.
838   if (succeeded(parser.parseOptionalKeyword(GPUFuncOp::getKernelKeyword())))
839     result.addAttribute(GPUDialect::getKernelFuncAttrName(),
840                         builder.getUnitAttr());
841 
842   // Parse attributes.
843   if (failed(parser.parseOptionalAttrDictWithKeyword(result.attributes)))
844     return failure();
845   function_interface_impl::addArgAndResultAttrs(builder, result, argAttrs,
846                                                 resultAttrs);
847 
848   // Parse the region. If no argument names were provided, take all names
849   // (including those of attributions) from the entry block.
850   auto *body = result.addRegion();
851   return parser.parseRegion(*body, entryArgs, argTypes);
852 }
853 
854 static void printAttributions(OpAsmPrinter &p, StringRef keyword,
855                               ArrayRef<BlockArgument> values) {
856   if (values.empty())
857     return;
858 
859   p << ' ' << keyword << '(';
860   llvm::interleaveComma(
861       values, p, [&p](BlockArgument v) { p << v << " : " << v.getType(); });
862   p << ')';
863 }
864 
865 /// Prints a GPU Func op.
866 static void printGPUFuncOp(OpAsmPrinter &p, GPUFuncOp op) {
867   p << ' ';
868   p.printSymbolName(op.getName());
869 
870   FunctionType type = op.getType();
871   function_interface_impl::printFunctionSignature(
872       p, op.getOperation(), type.getInputs(),
873       /*isVariadic=*/false, type.getResults());
874 
875   printAttributions(p, op.getWorkgroupKeyword(), op.getWorkgroupAttributions());
876   printAttributions(p, op.getPrivateKeyword(), op.getPrivateAttributions());
877   if (op.isKernel())
878     p << ' ' << op.getKernelKeyword();
879 
880   function_interface_impl::printFunctionAttributes(
881       p, op.getOperation(), type.getNumInputs(), type.getNumResults(),
882       {op.getNumWorkgroupAttributionsAttrName(),
883        GPUDialect::getKernelFuncAttrName()});
884   p << ' ';
885   p.printRegion(op.getBody(), /*printEntryBlockArgs=*/false);
886 }
887 
888 LogicalResult GPUFuncOp::verifyType() {
889   Type type = getTypeAttr().getValue();
890   if (!type.isa<FunctionType>())
891     return emitOpError("requires '" + getTypeAttrName() +
892                        "' attribute of function type");
893 
894   if (isKernel() && getType().getNumResults() != 0)
895     return emitOpError() << "expected void return type for kernel function";
896 
897   return success();
898 }
899 
900 static LogicalResult verifyAttributions(Operation *op,
901                                         ArrayRef<BlockArgument> attributions,
902                                         unsigned memorySpace) {
903   for (Value v : attributions) {
904     auto type = v.getType().dyn_cast<MemRefType>();
905     if (!type)
906       return op->emitOpError() << "expected memref type in attribution";
907 
908     if (type.getMemorySpaceAsInt() != memorySpace) {
909       return op->emitOpError()
910              << "expected memory space " << memorySpace << " in attribution";
911     }
912   }
913   return success();
914 }
915 
916 /// Verifies the body of the function.
917 LogicalResult GPUFuncOp::verifyBody() {
918   unsigned numFuncArguments = getNumArguments();
919   unsigned numWorkgroupAttributions = getNumWorkgroupAttributions();
920   unsigned numBlockArguments = front().getNumArguments();
921   if (numBlockArguments < numFuncArguments + numWorkgroupAttributions)
922     return emitOpError() << "expected at least "
923                          << numFuncArguments + numWorkgroupAttributions
924                          << " arguments to body region";
925 
926   ArrayRef<Type> funcArgTypes = getType().getInputs();
927   for (unsigned i = 0; i < numFuncArguments; ++i) {
928     Type blockArgType = front().getArgument(i).getType();
929     if (funcArgTypes[i] != blockArgType)
930       return emitOpError() << "expected body region argument #" << i
931                            << " to be of type " << funcArgTypes[i] << ", got "
932                            << blockArgType;
933   }
934 
935   if (failed(verifyAttributions(getOperation(), getWorkgroupAttributions(),
936                                 GPUDialect::getWorkgroupAddressSpace())) ||
937       failed(verifyAttributions(getOperation(), getPrivateAttributions(),
938                                 GPUDialect::getPrivateAddressSpace())))
939     return failure();
940 
941   return success();
942 }
943 
944 //===----------------------------------------------------------------------===//
945 // ReturnOp
946 //===----------------------------------------------------------------------===//
947 
948 static LogicalResult verify(gpu::ReturnOp returnOp) {
949   GPUFuncOp function = returnOp->getParentOfType<GPUFuncOp>();
950 
951   FunctionType funType = function.getType();
952 
953   if (funType.getNumResults() != returnOp.operands().size())
954     return returnOp.emitOpError()
955         .append("expected ", funType.getNumResults(), " result operands")
956         .attachNote(function.getLoc())
957         .append("return type declared here");
958 
959   for (const auto &pair : llvm::enumerate(
960            llvm::zip(function.getType().getResults(), returnOp.operands()))) {
961     Type type;
962     Value operand;
963     std::tie(type, operand) = pair.value();
964     if (type != operand.getType())
965       return returnOp.emitOpError() << "unexpected type `" << operand.getType()
966                                     << "' for operand #" << pair.index();
967   }
968   return success();
969 }
970 
971 //===----------------------------------------------------------------------===//
972 // GPUModuleOp
973 //===----------------------------------------------------------------------===//
974 
975 void GPUModuleOp::build(OpBuilder &builder, OperationState &result,
976                         StringRef name) {
977   ensureTerminator(*result.addRegion(), builder, result.location);
978   result.attributes.push_back(builder.getNamedAttr(
979       ::mlir::SymbolTable::getSymbolAttrName(), builder.getStringAttr(name)));
980 }
981 
982 static ParseResult parseGPUModuleOp(OpAsmParser &parser,
983                                     OperationState &result) {
984   StringAttr nameAttr;
985   if (parser.parseSymbolName(nameAttr, SymbolTable::getSymbolAttrName(),
986                              result.attributes))
987     return failure();
988 
989   // If module attributes are present, parse them.
990   if (parser.parseOptionalAttrDictWithKeyword(result.attributes))
991     return failure();
992 
993   // Parse the module body.
994   auto *body = result.addRegion();
995   if (parser.parseRegion(*body, None, None))
996     return failure();
997 
998   // Ensure that this module has a valid terminator.
999   GPUModuleOp::ensureTerminator(*body, parser.getBuilder(), result.location);
1000   return success();
1001 }
1002 
1003 static void print(OpAsmPrinter &p, GPUModuleOp op) {
1004   p << ' ';
1005   p.printSymbolName(op.getName());
1006   p.printOptionalAttrDictWithKeyword(op->getAttrs(),
1007                                      {SymbolTable::getSymbolAttrName()});
1008   p << ' ';
1009   p.printRegion(op->getRegion(0), /*printEntryBlockArgs=*/false,
1010                 /*printBlockTerminators=*/false);
1011 }
1012 
1013 //===----------------------------------------------------------------------===//
1014 // GPUMemcpyOp
1015 //===----------------------------------------------------------------------===//
1016 
1017 static LogicalResult verify(MemcpyOp op) {
1018   auto srcType = op.src().getType();
1019   auto dstType = op.dst().getType();
1020 
1021   if (getElementTypeOrSelf(srcType) != getElementTypeOrSelf(dstType))
1022     return op.emitOpError("arguments have incompatible element type");
1023 
1024   if (failed(verifyCompatibleShape(srcType, dstType)))
1025     return op.emitOpError("arguments have incompatible shape");
1026 
1027   return success();
1028 }
1029 
1030 static ParseResult parseAsyncDependencies(
1031     OpAsmParser &parser, Type &asyncTokenType,
1032     SmallVectorImpl<OpAsmParser::OperandType> &asyncDependencies) {
1033   auto loc = parser.getCurrentLocation();
1034   if (succeeded(parser.parseOptionalKeyword("async"))) {
1035     if (parser.getNumResults() == 0)
1036       return parser.emitError(loc, "needs to be named when marked 'async'");
1037     asyncTokenType = parser.getBuilder().getType<AsyncTokenType>();
1038   }
1039   return parser.parseOperandList(asyncDependencies,
1040                                  OpAsmParser::Delimiter::OptionalSquare);
1041 }
1042 
1043 static void printAsyncDependencies(OpAsmPrinter &printer, Operation *op,
1044                                    Type asyncTokenType,
1045                                    OperandRange asyncDependencies) {
1046   if (asyncTokenType)
1047     printer << "async ";
1048   if (asyncDependencies.empty())
1049     return;
1050   printer << "[";
1051   llvm::interleaveComma(asyncDependencies, printer);
1052   printer << "]";
1053 }
1054 
1055 //===----------------------------------------------------------------------===//
1056 // GPU_SubgroupMmaLoadMatrixOp
1057 //===----------------------------------------------------------------------===//
1058 
1059 static LogicalResult verify(SubgroupMmaLoadMatrixOp op) {
1060   auto srcType = op.srcMemref().getType();
1061   auto resType = op.res().getType();
1062   auto resMatrixType = resType.cast<gpu::MMAMatrixType>();
1063   auto operand = resMatrixType.getOperand();
1064   auto srcMemrefType = srcType.cast<MemRefType>();
1065   auto srcMemSpace = srcMemrefType.getMemorySpaceAsInt();
1066 
1067   if (!srcMemrefType.getLayout().isIdentity())
1068     return op.emitError("expected identity layout map for source memref");
1069 
1070   if (srcMemSpace != kGenericMemorySpace && srcMemSpace != kSharedMemorySpace &&
1071       srcMemSpace != kGlobalMemorySpace)
1072     return op.emitError(
1073         "source memorySpace kGenericMemorySpace, kSharedMemorySpace or "
1074         "kGlobalMemorySpace only allowed");
1075 
1076   if (!operand.equals("AOp") && !operand.equals("BOp") &&
1077       !operand.equals("COp"))
1078     return op.emitError("only AOp, BOp and COp can be loaded");
1079 
1080   return success();
1081 }
1082 
1083 //===----------------------------------------------------------------------===//
1084 // GPU_SubgroupMmaStoreMatrixOp
1085 //===----------------------------------------------------------------------===//
1086 
1087 static LogicalResult verify(SubgroupMmaStoreMatrixOp op) {
1088   auto srcType = op.src().getType();
1089   auto dstType = op.dstMemref().getType();
1090   auto srcMatrixType = srcType.cast<gpu::MMAMatrixType>();
1091   auto dstMemrefType = dstType.cast<MemRefType>();
1092   auto dstMemSpace = dstMemrefType.getMemorySpaceAsInt();
1093   if (!dstMemrefType.getLayout().isIdentity())
1094     return op.emitError("expected identity layout map for destination memref");
1095 
1096   if (dstMemSpace != kGenericMemorySpace && dstMemSpace != kSharedMemorySpace &&
1097       dstMemSpace != kGlobalMemorySpace)
1098     return op.emitError(
1099         "destination memorySpace of kGenericMemorySpace, "
1100         "kGlobalMemorySpace or kSharedMemorySpace only allowed");
1101 
1102   if (!srcMatrixType.getOperand().equals("COp"))
1103     return op.emitError(
1104         "expected the operand matrix being stored to have 'COp' operand type");
1105 
1106   return success();
1107 }
1108 
1109 //===----------------------------------------------------------------------===//
1110 // GPU_SubgroupMmaComputeOp
1111 //===----------------------------------------------------------------------===//
1112 
1113 static LogicalResult verify(SubgroupMmaComputeOp op) {
1114   enum OperandMap { A, B, C };
1115   SmallVector<MMAMatrixType, 3> opTypes;
1116 
1117   auto populateOpInfo = [&opTypes, &op]() {
1118     opTypes.push_back(op.opA().getType().cast<MMAMatrixType>());
1119     opTypes.push_back(op.opB().getType().cast<MMAMatrixType>());
1120     opTypes.push_back(op.opC().getType().cast<MMAMatrixType>());
1121   };
1122   populateOpInfo();
1123 
1124   if (!opTypes[A].getOperand().equals("AOp") ||
1125       !opTypes[B].getOperand().equals("BOp") ||
1126       !opTypes[C].getOperand().equals("COp"))
1127     return op.emitError("operands must be in the order AOp, BOp, COp");
1128 
1129   ArrayRef<int64_t> aShape, bShape, cShape;
1130   aShape = opTypes[A].getShape();
1131   bShape = opTypes[B].getShape();
1132   cShape = opTypes[C].getShape();
1133 
1134   if (aShape[1] != bShape[0] || aShape[0] != cShape[0] ||
1135       bShape[1] != cShape[1])
1136     return op.emitError("operand shapes do not satisfy matmul constraints");
1137 
1138   return success();
1139 }
1140 
1141 /// This is a common class used for patterns of the form
1142 /// "someop(memrefcast) -> someop".  It folds the source of any memref.cast
1143 /// into the root operation directly.
1144 static LogicalResult foldMemRefCast(Operation *op) {
1145   bool folded = false;
1146   for (OpOperand &operand : op->getOpOperands()) {
1147     auto cast = operand.get().getDefiningOp<mlir::memref::CastOp>();
1148     if (cast) {
1149       operand.set(cast.getOperand());
1150       folded = true;
1151     }
1152   }
1153   return success(folded);
1154 }
1155 
1156 LogicalResult MemcpyOp::fold(ArrayRef<Attribute> operands,
1157                              SmallVectorImpl<::mlir::OpFoldResult> &results) {
1158   return foldMemRefCast(*this);
1159 }
1160 
1161 LogicalResult MemsetOp::fold(ArrayRef<Attribute> operands,
1162                              SmallVectorImpl<::mlir::OpFoldResult> &results) {
1163   return foldMemRefCast(*this);
1164 }
1165 
1166 //===----------------------------------------------------------------------===//
1167 // GPU_AllocOp
1168 //===----------------------------------------------------------------------===//
1169 namespace {
1170 
1171 /// Folding of memref.dim(gpu.alloc(%size), %idx) -> %size similar to
1172 /// `memref::AllocOp`.
1173 struct SimplifyDimOfAllocOp : public OpRewritePattern<memref::DimOp> {
1174   using OpRewritePattern<memref::DimOp>::OpRewritePattern;
1175 
1176   LogicalResult matchAndRewrite(memref::DimOp dimOp,
1177                                 PatternRewriter &rewriter) const override {
1178     auto index = dimOp.index().getDefiningOp<arith::ConstantIndexOp>();
1179     if (!index)
1180       return failure();
1181 
1182     auto memrefType = dimOp.source().getType().dyn_cast<MemRefType>();
1183     if (!memrefType || !memrefType.isDynamicDim(index.value()))
1184       return failure();
1185 
1186     auto alloc = dimOp.source().getDefiningOp<AllocOp>();
1187     if (!alloc)
1188       return failure();
1189 
1190     Value substituteOp = *(alloc.dynamicSizes().begin() +
1191                            memrefType.getDynamicDimIndex(index.value()));
1192     rewriter.replaceOp(dimOp, substituteOp);
1193     return success();
1194   }
1195 };
1196 
1197 } // namespace
1198 
1199 void AllocOp::getCanonicalizationPatterns(RewritePatternSet &results,
1200                                           MLIRContext *context) {
1201   results.add<SimplifyDimOfAllocOp>(context);
1202 }
1203 
1204 #include "mlir/Dialect/GPU/GPUOpInterfaces.cpp.inc"
1205 #include "mlir/Dialect/GPU/GPUOpsEnums.cpp.inc"
1206 
1207 #define GET_ATTRDEF_CLASSES
1208 #include "mlir/Dialect/GPU/GPUOpsAttributes.cpp.inc"
1209 
1210 #define GET_OP_CLASSES
1211 #include "mlir/Dialect/GPU/GPUOps.cpp.inc"
1212