1 //===- MLIRContext.cpp - MLIR Type Classes --------------------------------===//
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/IR/MLIRContext.h"
10 #include "AffineExprDetail.h"
11 #include "AffineMapDetail.h"
12 #include "AttributeDetail.h"
13 #include "IntegerSetDetail.h"
14 #include "LocationDetail.h"
15 #include "TypeDetail.h"
16 #include "mlir/IR/AffineExpr.h"
17 #include "mlir/IR/AffineMap.h"
18 #include "mlir/IR/Attributes.h"
19 #include "mlir/IR/Diagnostics.h"
20 #include "mlir/IR/Dialect.h"
21 #include "mlir/IR/Function.h"
22 #include "mlir/IR/Identifier.h"
23 #include "mlir/IR/IntegerSet.h"
24 #include "mlir/IR/Location.h"
25 #include "mlir/IR/Module.h"
26 #include "mlir/IR/Types.h"
27 #include "llvm/ADT/DenseMap.h"
28 #include "llvm/ADT/DenseSet.h"
29 #include "llvm/ADT/SetVector.h"
30 #include "llvm/ADT/StringSet.h"
31 #include "llvm/ADT/Twine.h"
32 #include "llvm/Support/Allocator.h"
33 #include "llvm/Support/CommandLine.h"
34 #include "llvm/Support/RWMutex.h"
35 #include "llvm/Support/raw_ostream.h"
36 #include <memory>
37 
38 using namespace mlir;
39 using namespace mlir::detail;
40 
41 using llvm::hash_combine;
42 using llvm::hash_combine_range;
43 
44 //===----------------------------------------------------------------------===//
45 // MLIRContext CommandLine Options
46 //===----------------------------------------------------------------------===//
47 
48 namespace {
49 /// This struct contains command line options that can be used to initialize
50 /// various bits of an MLIRContext. This uses a struct wrapper to avoid the need
51 /// for global command line options.
52 struct MLIRContextOptions {
53   llvm::cl::opt<bool> printOpOnDiagnostic{
54       "mlir-print-op-on-diagnostic",
55       llvm::cl::desc("When a diagnostic is emitted on an operation, also print "
56                      "the operation as an attached note"),
57       llvm::cl::init(true)};
58 
59   llvm::cl::opt<bool> printStackTraceOnDiagnostic{
60       "mlir-print-stacktrace-on-diagnostic",
61       llvm::cl::desc("When a diagnostic is emitted, also print the stack trace "
62                      "as an attached note")};
63 };
64 } // end anonymous namespace
65 
66 static llvm::ManagedStatic<MLIRContextOptions> clOptions;
67 
68 /// Register a set of useful command-line options that can be used to configure
69 /// various flags within the MLIRContext. These flags are used when constructing
70 /// an MLIR context for initialization.
71 void mlir::registerMLIRContextCLOptions() {
72   // Make sure that the options struct has been initialized.
73   *clOptions;
74 }
75 
76 //===----------------------------------------------------------------------===//
77 // Builtin Dialect
78 //===----------------------------------------------------------------------===//
79 
80 namespace {
81 /// A builtin dialect to define types/etc that are necessary for the validity of
82 /// the IR.
83 struct BuiltinDialect : public Dialect {
84   BuiltinDialect(MLIRContext *context) : Dialect(/*name=*/"", context) {
85     addAttributes<AffineMapAttr, ArrayAttr, BoolAttr, DenseIntOrFPElementsAttr,
86                   DenseStringElementsAttr, DictionaryAttr, FloatAttr,
87                   SymbolRefAttr, IntegerAttr, IntegerSetAttr, OpaqueAttr,
88                   OpaqueElementsAttr, SparseElementsAttr, StringAttr, TypeAttr,
89                   UnitAttr>();
90     addAttributes<CallSiteLoc, FileLineColLoc, FusedLoc, NameLoc, OpaqueLoc,
91                   UnknownLoc>();
92 
93     addTypes<ComplexType, FloatType, FunctionType, IndexType, IntegerType,
94              MemRefType, UnrankedMemRefType, NoneType, OpaqueType,
95              RankedTensorType, TupleType, UnrankedTensorType, VectorType>();
96 
97     // TODO: These operations should be moved to a different dialect when they
98     // have been fully decoupled from the core.
99     addOperations<FuncOp, ModuleOp, ModuleTerminatorOp>();
100   }
101 };
102 } // end anonymous namespace.
103 
104 //===----------------------------------------------------------------------===//
105 // AffineMap and IntegerSet hashing
106 //===----------------------------------------------------------------------===//
107 
108 /// A utility function to safely get or create a uniqued instance within the
109 /// given set container.
110 template <typename ValueT, typename DenseInfoT, typename KeyT,
111           typename ConstructorFn>
112 static ValueT safeGetOrCreate(DenseSet<ValueT, DenseInfoT> &container,
113                               KeyT &&key, llvm::sys::SmartRWMutex<true> &mutex,
114                               ConstructorFn &&constructorFn) {
115   { // Check for an existing instance in read-only mode.
116     llvm::sys::SmartScopedReader<true> instanceLock(mutex);
117     auto it = container.find_as(key);
118     if (it != container.end())
119       return *it;
120   }
121 
122   // Acquire a writer-lock so that we can safely create the new instance.
123   llvm::sys::SmartScopedWriter<true> instanceLock(mutex);
124 
125   // Check for an existing instance again here, because another writer thread
126   // may have already created one.
127   auto existing = container.insert_as(ValueT(), key);
128   if (!existing.second)
129     return *existing.first;
130 
131   // Otherwise, construct a new instance of the value.
132   return *existing.first = constructorFn();
133 }
134 
135 namespace {
136 struct AffineMapKeyInfo : DenseMapInfo<AffineMap> {
137   // Affine maps are uniqued based on their dim/symbol counts and affine
138   // expressions.
139   using KeyTy = std::tuple<unsigned, unsigned, ArrayRef<AffineExpr>>;
140   using DenseMapInfo<AffineMap>::isEqual;
141 
142   static unsigned getHashValue(const AffineMap &key) {
143     return getHashValue(
144         KeyTy(key.getNumDims(), key.getNumSymbols(), key.getResults()));
145   }
146 
147   static unsigned getHashValue(KeyTy key) {
148     return hash_combine(
149         std::get<0>(key), std::get<1>(key),
150         hash_combine_range(std::get<2>(key).begin(), std::get<2>(key).end()));
151   }
152 
153   static bool isEqual(const KeyTy &lhs, AffineMap rhs) {
154     if (rhs == getEmptyKey() || rhs == getTombstoneKey())
155       return false;
156     return lhs == std::make_tuple(rhs.getNumDims(), rhs.getNumSymbols(),
157                                   rhs.getResults());
158   }
159 };
160 
161 struct IntegerSetKeyInfo : DenseMapInfo<IntegerSet> {
162   // Integer sets are uniqued based on their dim/symbol counts, affine
163   // expressions appearing in the LHS of constraints, and eqFlags.
164   using KeyTy =
165       std::tuple<unsigned, unsigned, ArrayRef<AffineExpr>, ArrayRef<bool>>;
166   using DenseMapInfo<IntegerSet>::isEqual;
167 
168   static unsigned getHashValue(const IntegerSet &key) {
169     return getHashValue(KeyTy(key.getNumDims(), key.getNumSymbols(),
170                               key.getConstraints(), key.getEqFlags()));
171   }
172 
173   static unsigned getHashValue(KeyTy key) {
174     return hash_combine(
175         std::get<0>(key), std::get<1>(key),
176         hash_combine_range(std::get<2>(key).begin(), std::get<2>(key).end()),
177         hash_combine_range(std::get<3>(key).begin(), std::get<3>(key).end()));
178   }
179 
180   static bool isEqual(const KeyTy &lhs, IntegerSet rhs) {
181     if (rhs == getEmptyKey() || rhs == getTombstoneKey())
182       return false;
183     return lhs == std::make_tuple(rhs.getNumDims(), rhs.getNumSymbols(),
184                                   rhs.getConstraints(), rhs.getEqFlags());
185   }
186 };
187 } // end anonymous namespace.
188 
189 //===----------------------------------------------------------------------===//
190 // MLIRContextImpl
191 //===----------------------------------------------------------------------===//
192 
193 namespace mlir {
194 /// This is the implementation of the MLIRContext class, using the pImpl idiom.
195 /// This class is completely private to this file, so everything is public.
196 class MLIRContextImpl {
197 public:
198   //===--------------------------------------------------------------------===//
199   // Identifier uniquing
200   //===--------------------------------------------------------------------===//
201 
202   // Identifier allocator and mutex for thread safety.
203   llvm::BumpPtrAllocator identifierAllocator;
204   llvm::sys::SmartRWMutex<true> identifierMutex;
205 
206   //===--------------------------------------------------------------------===//
207   // Diagnostics
208   //===--------------------------------------------------------------------===//
209   DiagnosticEngine diagEngine;
210 
211   //===--------------------------------------------------------------------===//
212   // Options
213   //===--------------------------------------------------------------------===//
214 
215   /// In most cases, creating operation in unregistered dialect is not desired
216   /// and indicate a misconfiguration of the compiler. This option enables to
217   /// detect such use cases
218   bool allowUnregisteredDialects = false;
219 
220   /// If the operation should be attached to diagnostics printed via the
221   /// Operation::emit methods.
222   bool printOpOnDiagnostic = true;
223 
224   /// If the current stack trace should be attached when emitting diagnostics.
225   bool printStackTraceOnDiagnostic = false;
226 
227   //===--------------------------------------------------------------------===//
228   // Other
229   //===--------------------------------------------------------------------===//
230 
231   /// A general purpose mutex to lock access to parts of the context that do not
232   /// have a more specific mutex, e.g. registry operations.
233   llvm::sys::SmartRWMutex<true> contextMutex;
234 
235   /// This is a list of dialects that are created referring to this context.
236   /// The MLIRContext owns the objects.
237   std::vector<std::unique_ptr<Dialect>> dialects;
238 
239   /// This is a mapping from operation name to AbstractOperation for registered
240   /// operations.
241   llvm::StringMap<AbstractOperation> registeredOperations;
242 
243   /// This is a mapping from type id to Dialect for registered attributes and
244   /// types.
245   DenseMap<TypeID, Dialect *> registeredDialectSymbols;
246 
247   /// These are identifiers uniqued into this MLIRContext.
248   llvm::StringSet<llvm::BumpPtrAllocator &> identifiers;
249 
250   //===--------------------------------------------------------------------===//
251   // Affine uniquing
252   //===--------------------------------------------------------------------===//
253 
254   // Affine allocator and mutex for thread safety.
255   llvm::BumpPtrAllocator affineAllocator;
256   llvm::sys::SmartRWMutex<true> affineMutex;
257 
258   // Affine map uniquing.
259   using AffineMapSet = DenseSet<AffineMap, AffineMapKeyInfo>;
260   AffineMapSet affineMaps;
261 
262   // Integer set uniquing.
263   using IntegerSets = DenseSet<IntegerSet, IntegerSetKeyInfo>;
264   IntegerSets integerSets;
265 
266   // Affine expression uniquing.
267   StorageUniquer affineUniquer;
268 
269   //===--------------------------------------------------------------------===//
270   // Type uniquing
271   //===--------------------------------------------------------------------===//
272   StorageUniquer typeUniquer;
273 
274   /// Cached Type Instances.
275   FloatType bf16Ty, f16Ty, f32Ty, f64Ty;
276   IndexType indexTy;
277   IntegerType int1Ty, int8Ty, int16Ty, int32Ty, int64Ty, int128Ty;
278   NoneType noneType;
279 
280   //===--------------------------------------------------------------------===//
281   // Attribute uniquing
282   //===--------------------------------------------------------------------===//
283   StorageUniquer attributeUniquer;
284 
285   /// Cached Attribute Instances.
286   BoolAttr falseAttr, trueAttr;
287   UnitAttr unitAttr;
288   UnknownLoc unknownLocAttr;
289 
290 public:
291   MLIRContextImpl() : identifiers(identifierAllocator) {
292     // Initialize values based on the command line flags if they were provided.
293     if (clOptions.isConstructed()) {
294       printOpOnDiagnostic = clOptions->printOpOnDiagnostic;
295       printStackTraceOnDiagnostic = clOptions->printStackTraceOnDiagnostic;
296     }
297   }
298 };
299 } // end namespace mlir
300 
301 MLIRContext::MLIRContext() : impl(new MLIRContextImpl()) {
302   new BuiltinDialect(this);
303   registerAllDialects(this);
304 
305   // Initialize several common attributes and types to avoid the need to lock
306   // the context when accessing them.
307 
308   //// Types.
309   /// Floating-point Types.
310   impl->bf16Ty = TypeUniquer::get<FloatType>(this, StandardTypes::BF16);
311   impl->f16Ty = TypeUniquer::get<FloatType>(this, StandardTypes::F16);
312   impl->f32Ty = TypeUniquer::get<FloatType>(this, StandardTypes::F32);
313   impl->f64Ty = TypeUniquer::get<FloatType>(this, StandardTypes::F64);
314   /// Index Type.
315   impl->indexTy = TypeUniquer::get<IndexType>(this, StandardTypes::Index);
316   /// Integer Types.
317   impl->int1Ty = TypeUniquer::get<IntegerType>(this, StandardTypes::Integer, 1,
318                                                IntegerType::Signless);
319   impl->int8Ty = TypeUniquer::get<IntegerType>(this, StandardTypes::Integer, 8,
320                                                IntegerType::Signless);
321   impl->int16Ty = TypeUniquer::get<IntegerType>(this, StandardTypes::Integer,
322                                                 16, IntegerType::Signless);
323   impl->int32Ty = TypeUniquer::get<IntegerType>(this, StandardTypes::Integer,
324                                                 32, IntegerType::Signless);
325   impl->int64Ty = TypeUniquer::get<IntegerType>(this, StandardTypes::Integer,
326                                                 64, IntegerType::Signless);
327   impl->int128Ty = TypeUniquer::get<IntegerType>(this, StandardTypes::Integer,
328                                                  128, IntegerType::Signless);
329   /// None Type.
330   impl->noneType = TypeUniquer::get<NoneType>(this, StandardTypes::None);
331 
332   //// Attributes.
333   //// Note: These must be registered after the types as they may generate one
334   //// of the above types internally.
335   /// Bool Attributes.
336   // Note: The context is also used within the BoolAttrStorage.
337   impl->falseAttr = AttributeUniquer::get<BoolAttr>(
338       this, StandardAttributes::Bool, this, false);
339   impl->trueAttr = AttributeUniquer::get<BoolAttr>(
340       this, StandardAttributes::Bool, this, true);
341   /// Unit Attribute.
342   impl->unitAttr =
343       AttributeUniquer::get<UnitAttr>(this, StandardAttributes::Unit);
344   /// Unknown Location Attribute.
345   impl->unknownLocAttr = AttributeUniquer::get<UnknownLoc>(
346       this, StandardAttributes::UnknownLocation);
347 }
348 
349 MLIRContext::~MLIRContext() {}
350 
351 /// Copy the specified array of elements into memory managed by the provided
352 /// bump pointer allocator.  This assumes the elements are all PODs.
353 template <typename T>
354 static ArrayRef<T> copyArrayRefInto(llvm::BumpPtrAllocator &allocator,
355                                     ArrayRef<T> elements) {
356   auto result = allocator.Allocate<T>(elements.size());
357   std::uninitialized_copy(elements.begin(), elements.end(), result);
358   return ArrayRef<T>(result, elements.size());
359 }
360 
361 //===----------------------------------------------------------------------===//
362 // Diagnostic Handlers
363 //===----------------------------------------------------------------------===//
364 
365 /// Returns the diagnostic engine for this context.
366 DiagnosticEngine &MLIRContext::getDiagEngine() { return getImpl().diagEngine; }
367 
368 //===----------------------------------------------------------------------===//
369 // Dialect and Operation Registration
370 //===----------------------------------------------------------------------===//
371 
372 /// Return information about all registered IR dialects.
373 std::vector<Dialect *> MLIRContext::getRegisteredDialects() {
374   // Lock access to the context registry.
375   llvm::sys::SmartScopedReader<true> registryLock(getImpl().contextMutex);
376 
377   std::vector<Dialect *> result;
378   result.reserve(getImpl().dialects.size());
379   for (auto &dialect : getImpl().dialects)
380     result.push_back(dialect.get());
381   return result;
382 }
383 
384 /// Get a registered IR dialect with the given namespace. If none is found,
385 /// then return nullptr.
386 Dialect *MLIRContext::getRegisteredDialect(StringRef name) {
387   // Lock access to the context registry.
388   llvm::sys::SmartScopedReader<true> registryLock(getImpl().contextMutex);
389   for (auto &dialect : getImpl().dialects)
390     if (name == dialect->getNamespace())
391       return dialect.get();
392   return nullptr;
393 }
394 
395 /// Register this dialect object with the specified context.  The context
396 /// takes ownership of the heap allocated dialect.
397 void Dialect::registerDialect(MLIRContext *context) {
398   auto &impl = context->getImpl();
399   std::unique_ptr<Dialect> dialect(this);
400 
401   // Lock access to the context registry.
402   llvm::sys::SmartScopedWriter<true> registryLock(impl.contextMutex);
403 
404   // Get the correct insertion position sorted by namespace.
405   auto insertPt =
406       llvm::lower_bound(impl.dialects, dialect,
407                         [](const std::unique_ptr<Dialect> &lhs,
408                            const std::unique_ptr<Dialect> &rhs) {
409                           return lhs->getNamespace() < rhs->getNamespace();
410                         });
411 
412   // Abort if dialect with namespace has already been registered.
413   if (insertPt != impl.dialects.end() &&
414       (*insertPt)->getNamespace() == getNamespace()) {
415     llvm::report_fatal_error("a dialect with namespace '" + getNamespace() +
416                              "' has already been registered");
417   }
418   impl.dialects.insert(insertPt, std::move(dialect));
419 }
420 
421 bool MLIRContext::allowsUnregisteredDialects() {
422   return impl->allowUnregisteredDialects;
423 }
424 
425 void MLIRContext::allowUnregisteredDialects(bool allowing) {
426   impl->allowUnregisteredDialects = allowing;
427 }
428 
429 /// Return true if we should attach the operation to diagnostics emitted via
430 /// Operation::emit.
431 bool MLIRContext::shouldPrintOpOnDiagnostic() {
432   return impl->printOpOnDiagnostic;
433 }
434 
435 /// Set the flag specifying if we should attach the operation to diagnostics
436 /// emitted via Operation::emit.
437 void MLIRContext::printOpOnDiagnostic(bool enable) {
438   impl->printOpOnDiagnostic = enable;
439 }
440 
441 /// Return true if we should attach the current stacktrace to diagnostics when
442 /// emitted.
443 bool MLIRContext::shouldPrintStackTraceOnDiagnostic() {
444   return impl->printStackTraceOnDiagnostic;
445 }
446 
447 /// Set the flag specifying if we should attach the current stacktrace when
448 /// emitting diagnostics.
449 void MLIRContext::printStackTraceOnDiagnostic(bool enable) {
450   impl->printStackTraceOnDiagnostic = enable;
451 }
452 
453 /// Return information about all registered operations.  This isn't very
454 /// efficient, typically you should ask the operations about their properties
455 /// directly.
456 std::vector<AbstractOperation *> MLIRContext::getRegisteredOperations() {
457   std::vector<std::pair<StringRef, AbstractOperation *>> opsToSort;
458 
459   { // Lock access to the context registry.
460     llvm::sys::SmartScopedReader<true> registryLock(getImpl().contextMutex);
461 
462     // We just have the operations in a non-deterministic hash table order. Dump
463     // into a temporary array, then sort it by operation name to get a stable
464     // ordering.
465     llvm::StringMap<AbstractOperation> &registeredOps =
466         getImpl().registeredOperations;
467 
468     opsToSort.reserve(registeredOps.size());
469     for (auto &elt : registeredOps)
470       opsToSort.push_back({elt.first(), &elt.second});
471   }
472 
473   llvm::array_pod_sort(opsToSort.begin(), opsToSort.end());
474 
475   std::vector<AbstractOperation *> result;
476   result.reserve(opsToSort.size());
477   for (auto &elt : opsToSort)
478     result.push_back(elt.second);
479   return result;
480 }
481 
482 void Dialect::addOperation(AbstractOperation opInfo) {
483   assert((getNamespace().empty() ||
484           opInfo.name.split('.').first == getNamespace()) &&
485          "op name doesn't start with dialect namespace");
486   assert(&opInfo.dialect == this && "Dialect object mismatch");
487   auto &impl = context->getImpl();
488 
489   // Lock access to the context registry.
490   llvm::sys::SmartScopedWriter<true> registryLock(impl.contextMutex);
491   if (!impl.registeredOperations.insert({opInfo.name, opInfo}).second) {
492     llvm::errs() << "error: operation named '" << opInfo.name
493                  << "' is already registered.\n";
494     abort();
495   }
496 }
497 
498 /// Register a dialect-specific symbol(e.g. type) with the current context.
499 void Dialect::addSymbol(TypeID typeID) {
500   auto &impl = context->getImpl();
501 
502   // Lock access to the context registry.
503   llvm::sys::SmartScopedWriter<true> registryLock(impl.contextMutex);
504   if (!impl.registeredDialectSymbols.insert({typeID, this}).second) {
505     llvm::errs() << "error: dialect symbol already registered.\n";
506     abort();
507   }
508 }
509 
510 /// Look up the specified operation in the operation set and return a pointer
511 /// to it if present.  Otherwise, return a null pointer.
512 const AbstractOperation *AbstractOperation::lookup(StringRef opName,
513                                                    MLIRContext *context) {
514   auto &impl = context->getImpl();
515 
516   // Lock access to the context registry.
517   llvm::sys::SmartScopedReader<true> registryLock(impl.contextMutex);
518   auto it = impl.registeredOperations.find(opName);
519   if (it != impl.registeredOperations.end())
520     return &it->second;
521   return nullptr;
522 }
523 
524 //===----------------------------------------------------------------------===//
525 // Identifier uniquing
526 //===----------------------------------------------------------------------===//
527 
528 /// Return an identifier for the specified string.
529 Identifier Identifier::get(StringRef str, MLIRContext *context) {
530   auto &impl = context->getImpl();
531 
532   { // Check for an existing identifier in read-only mode.
533     llvm::sys::SmartScopedReader<true> contextLock(impl.identifierMutex);
534     auto it = impl.identifiers.find(str);
535     if (it != impl.identifiers.end())
536       return Identifier(&*it);
537   }
538 
539   // Check invariants after seeing if we already have something in the
540   // identifier table - if we already had it in the table, then it already
541   // passed invariant checks.
542   assert(!str.empty() && "Cannot create an empty identifier");
543   assert(str.find('\0') == StringRef::npos &&
544          "Cannot create an identifier with a nul character");
545 
546   // Acquire a writer-lock so that we can safely create the new instance.
547   llvm::sys::SmartScopedWriter<true> contextLock(impl.identifierMutex);
548   auto it = impl.identifiers.insert(str).first;
549   return Identifier(&*it);
550 }
551 
552 //===----------------------------------------------------------------------===//
553 // Type uniquing
554 //===----------------------------------------------------------------------===//
555 
556 static Dialect &lookupDialectForSymbol(MLIRContext *ctx, TypeID typeID) {
557   auto &impl = ctx->getImpl();
558   auto it = impl.registeredDialectSymbols.find(typeID);
559   assert(it != impl.registeredDialectSymbols.end() &&
560          "symbol is not registered.");
561   return *it->second;
562 }
563 
564 /// Returns the storage uniquer used for constructing type storage instances.
565 /// This should not be used directly.
566 StorageUniquer &MLIRContext::getTypeUniquer() { return getImpl().typeUniquer; }
567 
568 /// Get the dialect that registered the type with the provided typeid.
569 Dialect &TypeUniquer::lookupDialectForType(MLIRContext *ctx, TypeID typeID) {
570   return lookupDialectForSymbol(ctx, typeID);
571 }
572 
573 FloatType FloatType::get(StandardTypes::Kind kind, MLIRContext *context) {
574   assert(kindof(kind) && "Not a FP kind.");
575   switch (kind) {
576   case StandardTypes::BF16:
577     return context->getImpl().bf16Ty;
578   case StandardTypes::F16:
579     return context->getImpl().f16Ty;
580   case StandardTypes::F32:
581     return context->getImpl().f32Ty;
582   case StandardTypes::F64:
583     return context->getImpl().f64Ty;
584   default:
585     llvm_unreachable("unexpected floating-point kind");
586   }
587 }
588 
589 /// Get an instance of the IndexType.
590 IndexType IndexType::get(MLIRContext *context) {
591   return context->getImpl().indexTy;
592 }
593 
594 /// Return an existing integer type instance if one is cached within the
595 /// context.
596 static IntegerType
597 getCachedIntegerType(unsigned width,
598                      IntegerType::SignednessSemantics signedness,
599                      MLIRContext *context) {
600   if (signedness != IntegerType::Signless)
601     return IntegerType();
602 
603   switch (width) {
604   case 1:
605     return context->getImpl().int1Ty;
606   case 8:
607     return context->getImpl().int8Ty;
608   case 16:
609     return context->getImpl().int16Ty;
610   case 32:
611     return context->getImpl().int32Ty;
612   case 64:
613     return context->getImpl().int64Ty;
614   case 128:
615     return context->getImpl().int128Ty;
616   default:
617     return IntegerType();
618   }
619 }
620 
621 IntegerType IntegerType::get(unsigned width, MLIRContext *context) {
622   return get(width, IntegerType::Signless, context);
623 }
624 
625 IntegerType IntegerType::get(unsigned width,
626                              IntegerType::SignednessSemantics signedness,
627                              MLIRContext *context) {
628   if (auto cached = getCachedIntegerType(width, signedness, context))
629     return cached;
630   return Base::get(context, StandardTypes::Integer, width, signedness);
631 }
632 
633 IntegerType IntegerType::getChecked(unsigned width, Location location) {
634   return getChecked(width, IntegerType::Signless, location);
635 }
636 
637 IntegerType IntegerType::getChecked(unsigned width,
638                                     SignednessSemantics signedness,
639                                     Location location) {
640   if (auto cached =
641           getCachedIntegerType(width, signedness, location->getContext()))
642     return cached;
643   return Base::getChecked(location, StandardTypes::Integer, width, signedness);
644 }
645 
646 /// Get an instance of the NoneType.
647 NoneType NoneType::get(MLIRContext *context) {
648   return context->getImpl().noneType;
649 }
650 
651 //===----------------------------------------------------------------------===//
652 // Attribute uniquing
653 //===----------------------------------------------------------------------===//
654 
655 /// Returns the storage uniquer used for constructing attribute storage
656 /// instances. This should not be used directly.
657 StorageUniquer &MLIRContext::getAttributeUniquer() {
658   return getImpl().attributeUniquer;
659 }
660 
661 /// Initialize the given attribute storage instance.
662 void AttributeUniquer::initializeAttributeStorage(AttributeStorage *storage,
663                                                   MLIRContext *ctx,
664                                                   TypeID attrID) {
665   storage->initializeDialect(lookupDialectForSymbol(ctx, attrID));
666 
667   // If the attribute did not provide a type, then default to NoneType.
668   if (!storage->getType())
669     storage->setType(NoneType::get(ctx));
670 }
671 
672 BoolAttr BoolAttr::get(bool value, MLIRContext *context) {
673   return value ? context->getImpl().trueAttr : context->getImpl().falseAttr;
674 }
675 
676 UnitAttr UnitAttr::get(MLIRContext *context) {
677   return context->getImpl().unitAttr;
678 }
679 
680 Location UnknownLoc::get(MLIRContext *context) {
681   return context->getImpl().unknownLocAttr;
682 }
683 
684 //===----------------------------------------------------------------------===//
685 // AffineMap uniquing
686 //===----------------------------------------------------------------------===//
687 
688 StorageUniquer &MLIRContext::getAffineUniquer() {
689   return getImpl().affineUniquer;
690 }
691 
692 AffineMap AffineMap::getImpl(unsigned dimCount, unsigned symbolCount,
693                              ArrayRef<AffineExpr> results,
694                              MLIRContext *context) {
695   auto &impl = context->getImpl();
696   auto key = std::make_tuple(dimCount, symbolCount, results);
697 
698   // Safely get or create an AffineMap instance.
699   return safeGetOrCreate(impl.affineMaps, key, impl.affineMutex, [&] {
700     auto *res = impl.affineAllocator.Allocate<detail::AffineMapStorage>();
701 
702     // Copy the results into the bump pointer.
703     results = copyArrayRefInto(impl.affineAllocator, results);
704 
705     // Initialize the memory using placement new.
706     new (res) detail::AffineMapStorage{dimCount, symbolCount, results, context};
707     return AffineMap(res);
708   });
709 }
710 
711 AffineMap AffineMap::get(MLIRContext *context) {
712   return getImpl(/*dimCount=*/0, /*symbolCount=*/0, /*results=*/{}, context);
713 }
714 
715 AffineMap AffineMap::get(unsigned dimCount, unsigned symbolCount,
716                          MLIRContext *context) {
717   return getImpl(dimCount, symbolCount, /*results=*/{}, context);
718 }
719 
720 AffineMap AffineMap::get(unsigned dimCount, unsigned symbolCount,
721                          AffineExpr result) {
722   return getImpl(dimCount, symbolCount, {result}, result.getContext());
723 }
724 
725 AffineMap AffineMap::get(unsigned dimCount, unsigned symbolCount,
726                          ArrayRef<AffineExpr> results, MLIRContext *context) {
727   return getImpl(dimCount, symbolCount, results, context);
728 }
729 
730 //===----------------------------------------------------------------------===//
731 // Integer Sets: these are allocated into the bump pointer, and are immutable.
732 // Unlike AffineMap's, these are uniqued only if they are small.
733 //===----------------------------------------------------------------------===//
734 
735 IntegerSet IntegerSet::get(unsigned dimCount, unsigned symbolCount,
736                            ArrayRef<AffineExpr> constraints,
737                            ArrayRef<bool> eqFlags) {
738   // The number of constraints can't be zero.
739   assert(!constraints.empty());
740   assert(constraints.size() == eqFlags.size());
741 
742   auto &impl = constraints[0].getContext()->getImpl();
743 
744   // A utility function to construct a new IntegerSetStorage instance.
745   auto constructorFn = [&] {
746     auto *res = impl.affineAllocator.Allocate<detail::IntegerSetStorage>();
747 
748     // Copy the results and equality flags into the bump pointer.
749     constraints = copyArrayRefInto(impl.affineAllocator, constraints);
750     eqFlags = copyArrayRefInto(impl.affineAllocator, eqFlags);
751 
752     // Initialize the memory using placement new.
753     new (res)
754         detail::IntegerSetStorage{dimCount, symbolCount, constraints, eqFlags};
755     return IntegerSet(res);
756   };
757 
758   // If this instance is uniqued, then we handle it separately so that multiple
759   // threads may simultaneously access existing instances.
760   if (constraints.size() < IntegerSet::kUniquingThreshold) {
761     auto key = std::make_tuple(dimCount, symbolCount, constraints, eqFlags);
762     return safeGetOrCreate(impl.integerSets, key, impl.affineMutex,
763                            constructorFn);
764   }
765 
766   // Otherwise, acquire a writer-lock so that we can safely create the new
767   // instance.
768   llvm::sys::SmartScopedWriter<true> affineLock(impl.affineMutex);
769   return constructorFn();
770 }
771 
772 //===----------------------------------------------------------------------===//
773 // StorageUniquerSupport
774 //===----------------------------------------------------------------------===//
775 
776 /// Utility method to generate a default location for use when checking the
777 /// construction invariants of a storage object. This is defined out-of-line to
778 /// avoid the need to include Location.h.
779 const AttributeStorage *
780 mlir::detail::generateUnknownStorageLocation(MLIRContext *ctx) {
781   return reinterpret_cast<const AttributeStorage *>(
782       ctx->getImpl().unknownLocAttr.getAsOpaquePointer());
783 }
784