clang  9.0.0svn
CodeGenTypes.cpp
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1 //===--- CodeGenTypes.cpp - Type translation for LLVM CodeGen -------------===//
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 is the code that handles AST -> LLVM type lowering.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "CodeGenTypes.h"
14 #include "CGCXXABI.h"
15 #include "CGCall.h"
16 #include "CGOpenCLRuntime.h"
17 #include "CGRecordLayout.h"
18 #include "TargetInfo.h"
19 #include "clang/AST/ASTContext.h"
20 #include "clang/AST/DeclCXX.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/AST/Expr.h"
23 #include "clang/AST/RecordLayout.h"
25 #include "llvm/IR/DataLayout.h"
26 #include "llvm/IR/DerivedTypes.h"
27 #include "llvm/IR/Module.h"
28 using namespace clang;
29 using namespace CodeGen;
30 
32  : CGM(cgm), Context(cgm.getContext()), TheModule(cgm.getModule()),
33  Target(cgm.getTarget()), TheCXXABI(cgm.getCXXABI()),
34  TheABIInfo(cgm.getTargetCodeGenInfo().getABIInfo()) {
35  SkippedLayout = false;
36 }
37 
39  llvm::DeleteContainerSeconds(CGRecordLayouts);
40 
41  for (llvm::FoldingSet<CGFunctionInfo>::iterator
42  I = FunctionInfos.begin(), E = FunctionInfos.end(); I != E; )
43  delete &*I++;
44 }
45 
47  return CGM.getCodeGenOpts();
48 }
49 
51  llvm::StructType *Ty,
52  StringRef suffix) {
53  SmallString<256> TypeName;
54  llvm::raw_svector_ostream OS(TypeName);
55  OS << RD->getKindName() << '.';
56 
57  // Name the codegen type after the typedef name
58  // if there is no tag type name available
59  if (RD->getIdentifier()) {
60  // FIXME: We should not have to check for a null decl context here.
61  // Right now we do it because the implicit Obj-C decls don't have one.
62  if (RD->getDeclContext())
63  RD->printQualifiedName(OS);
64  else
65  RD->printName(OS);
66  } else if (const TypedefNameDecl *TDD = RD->getTypedefNameForAnonDecl()) {
67  // FIXME: We should not have to check for a null decl context here.
68  // Right now we do it because the implicit Obj-C decls don't have one.
69  if (TDD->getDeclContext())
70  TDD->printQualifiedName(OS);
71  else
72  TDD->printName(OS);
73  } else
74  OS << "anon";
75 
76  if (!suffix.empty())
77  OS << suffix;
78 
79  Ty->setName(OS.str());
80 }
81 
82 /// ConvertTypeForMem - Convert type T into a llvm::Type. This differs from
83 /// ConvertType in that it is used to convert to the memory representation for
84 /// a type. For example, the scalar representation for _Bool is i1, but the
85 /// memory representation is usually i8 or i32, depending on the target.
87  llvm::Type *R = ConvertType(T);
88 
89  // If this is a non-bool type, don't map it.
90  if (!R->isIntegerTy(1))
91  return R;
92 
93  // Otherwise, return an integer of the target-specified size.
94  return llvm::IntegerType::get(getLLVMContext(),
95  (unsigned)Context.getTypeSize(T));
96 }
97 
98 
99 /// isRecordLayoutComplete - Return true if the specified type is already
100 /// completely laid out.
102  llvm::DenseMap<const Type*, llvm::StructType *>::const_iterator I =
103  RecordDeclTypes.find(Ty);
104  return I != RecordDeclTypes.end() && !I->second->isOpaque();
105 }
106 
107 static bool
109  llvm::SmallPtrSet<const RecordDecl*, 16> &AlreadyChecked);
110 
111 
112 /// isSafeToConvert - Return true if it is safe to convert the specified record
113 /// decl to IR and lay it out, false if doing so would cause us to get into a
114 /// recursive compilation mess.
115 static bool
117  llvm::SmallPtrSet<const RecordDecl*, 16> &AlreadyChecked) {
118  // If we have already checked this type (maybe the same type is used by-value
119  // multiple times in multiple structure fields, don't check again.
120  if (!AlreadyChecked.insert(RD).second)
121  return true;
122 
123  const Type *Key = CGT.getContext().getTagDeclType(RD).getTypePtr();
124 
125  // If this type is already laid out, converting it is a noop.
126  if (CGT.isRecordLayoutComplete(Key)) return true;
127 
128  // If this type is currently being laid out, we can't recursively compile it.
129  if (CGT.isRecordBeingLaidOut(Key))
130  return false;
131 
132  // If this type would require laying out bases that are currently being laid
133  // out, don't do it. This includes virtual base classes which get laid out
134  // when a class is translated, even though they aren't embedded by-value into
135  // the class.
136  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) {
137  for (const auto &I : CRD->bases())
138  if (!isSafeToConvert(I.getType()->getAs<RecordType>()->getDecl(),
139  CGT, AlreadyChecked))
140  return false;
141  }
142 
143  // If this type would require laying out members that are currently being laid
144  // out, don't do it.
145  for (const auto *I : RD->fields())
146  if (!isSafeToConvert(I->getType(), CGT, AlreadyChecked))
147  return false;
148 
149  // If there are no problems, lets do it.
150  return true;
151 }
152 
153 /// isSafeToConvert - Return true if it is safe to convert this field type,
154 /// which requires the structure elements contained by-value to all be
155 /// recursively safe to convert.
156 static bool
158  llvm::SmallPtrSet<const RecordDecl*, 16> &AlreadyChecked) {
159  // Strip off atomic type sugar.
160  if (const auto *AT = T->getAs<AtomicType>())
161  T = AT->getValueType();
162 
163  // If this is a record, check it.
164  if (const auto *RT = T->getAs<RecordType>())
165  return isSafeToConvert(RT->getDecl(), CGT, AlreadyChecked);
166 
167  // If this is an array, check the elements, which are embedded inline.
168  if (const auto *AT = CGT.getContext().getAsArrayType(T))
169  return isSafeToConvert(AT->getElementType(), CGT, AlreadyChecked);
170 
171  // Otherwise, there is no concern about transforming this. We only care about
172  // things that are contained by-value in a structure that can have another
173  // structure as a member.
174  return true;
175 }
176 
177 
178 /// isSafeToConvert - Return true if it is safe to convert the specified record
179 /// decl to IR and lay it out, false if doing so would cause us to get into a
180 /// recursive compilation mess.
181 static bool isSafeToConvert(const RecordDecl *RD, CodeGenTypes &CGT) {
182  // If no structs are being laid out, we can certainly do this one.
183  if (CGT.noRecordsBeingLaidOut()) return true;
184 
185  llvm::SmallPtrSet<const RecordDecl*, 16> AlreadyChecked;
186  return isSafeToConvert(RD, CGT, AlreadyChecked);
187 }
188 
189 /// isFuncParamTypeConvertible - Return true if the specified type in a
190 /// function parameter or result position can be converted to an IR type at this
191 /// point. This boils down to being whether it is complete, as well as whether
192 /// we've temporarily deferred expanding the type because we're in a recursive
193 /// context.
195  // Some ABIs cannot have their member pointers represented in IR unless
196  // certain circumstances have been reached.
197  if (const auto *MPT = Ty->getAs<MemberPointerType>())
199 
200  // If this isn't a tagged type, we can convert it!
201  const TagType *TT = Ty->getAs<TagType>();
202  if (!TT) return true;
203 
204  // Incomplete types cannot be converted.
205  if (TT->isIncompleteType())
206  return false;
207 
208  // If this is an enum, then it is always safe to convert.
209  const RecordType *RT = dyn_cast<RecordType>(TT);
210  if (!RT) return true;
211 
212  // Otherwise, we have to be careful. If it is a struct that we're in the
213  // process of expanding, then we can't convert the function type. That's ok
214  // though because we must be in a pointer context under the struct, so we can
215  // just convert it to a dummy type.
216  //
217  // We decide this by checking whether ConvertRecordDeclType returns us an
218  // opaque type for a struct that we know is defined.
219  return isSafeToConvert(RT->getDecl(), *this);
220 }
221 
222 
223 /// Code to verify a given function type is complete, i.e. the return type
224 /// and all of the parameter types are complete. Also check to see if we are in
225 /// a RS_StructPointer context, and if so whether any struct types have been
226 /// pended. If so, we don't want to ask the ABI lowering code to handle a type
227 /// that cannot be converted to an IR type.
230  return false;
231 
232  if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT))
233  for (unsigned i = 0, e = FPT->getNumParams(); i != e; i++)
234  if (!isFuncParamTypeConvertible(FPT->getParamType(i)))
235  return false;
236 
237  return true;
238 }
239 
240 /// UpdateCompletedType - When we find the full definition for a TagDecl,
241 /// replace the 'opaque' type we previously made for it if applicable.
243  // If this is an enum being completed, then we flush all non-struct types from
244  // the cache. This allows function types and other things that may be derived
245  // from the enum to be recomputed.
246  if (const EnumDecl *ED = dyn_cast<EnumDecl>(TD)) {
247  // Only flush the cache if we've actually already converted this type.
248  if (TypeCache.count(ED->getTypeForDecl())) {
249  // Okay, we formed some types based on this. We speculated that the enum
250  // would be lowered to i32, so we only need to flush the cache if this
251  // didn't happen.
252  if (!ConvertType(ED->getIntegerType())->isIntegerTy(32))
253  TypeCache.clear();
254  }
255  // If necessary, provide the full definition of a type only used with a
256  // declaration so far.
257  if (CGDebugInfo *DI = CGM.getModuleDebugInfo())
258  DI->completeType(ED);
259  return;
260  }
261 
262  // If we completed a RecordDecl that we previously used and converted to an
263  // anonymous type, then go ahead and complete it now.
264  const RecordDecl *RD = cast<RecordDecl>(TD);
265  if (RD->isDependentType()) return;
266 
267  // Only complete it if we converted it already. If we haven't converted it
268  // yet, we'll just do it lazily.
269  if (RecordDeclTypes.count(Context.getTagDeclType(RD).getTypePtr()))
271 
272  // If necessary, provide the full definition of a type only used with a
273  // declaration so far.
274  if (CGDebugInfo *DI = CGM.getModuleDebugInfo())
275  DI->completeType(RD);
276 }
277 
279  QualType T = Context.getRecordType(RD);
280  T = Context.getCanonicalType(T);
281 
282  const Type *Ty = T.getTypePtr();
283  if (RecordsWithOpaqueMemberPointers.count(Ty)) {
284  TypeCache.clear();
285  RecordsWithOpaqueMemberPointers.clear();
286  }
287 }
288 
289 static llvm::Type *getTypeForFormat(llvm::LLVMContext &VMContext,
290  const llvm::fltSemantics &format,
291  bool UseNativeHalf = false) {
292  if (&format == &llvm::APFloat::IEEEhalf()) {
293  if (UseNativeHalf)
294  return llvm::Type::getHalfTy(VMContext);
295  else
296  return llvm::Type::getInt16Ty(VMContext);
297  }
298  if (&format == &llvm::APFloat::IEEEsingle())
299  return llvm::Type::getFloatTy(VMContext);
300  if (&format == &llvm::APFloat::IEEEdouble())
301  return llvm::Type::getDoubleTy(VMContext);
302  if (&format == &llvm::APFloat::IEEEquad())
303  return llvm::Type::getFP128Ty(VMContext);
304  if (&format == &llvm::APFloat::PPCDoubleDouble())
305  return llvm::Type::getPPC_FP128Ty(VMContext);
306  if (&format == &llvm::APFloat::x87DoubleExtended())
307  return llvm::Type::getX86_FP80Ty(VMContext);
308  llvm_unreachable("Unknown float format!");
309 }
310 
311 llvm::Type *CodeGenTypes::ConvertFunctionTypeInternal(QualType QFT) {
312  assert(QFT.isCanonical());
313  const Type *Ty = QFT.getTypePtr();
314  const FunctionType *FT = cast<FunctionType>(QFT.getTypePtr());
315  // First, check whether we can build the full function type. If the
316  // function type depends on an incomplete type (e.g. a struct or enum), we
317  // cannot lower the function type.
318  if (!isFuncTypeConvertible(FT)) {
319  // This function's type depends on an incomplete tag type.
320 
321  // Force conversion of all the relevant record types, to make sure
322  // we re-convert the FunctionType when appropriate.
323  if (const RecordType *RT = FT->getReturnType()->getAs<RecordType>())
324  ConvertRecordDeclType(RT->getDecl());
325  if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT))
326  for (unsigned i = 0, e = FPT->getNumParams(); i != e; i++)
327  if (const RecordType *RT = FPT->getParamType(i)->getAs<RecordType>())
328  ConvertRecordDeclType(RT->getDecl());
329 
330  SkippedLayout = true;
331 
332  // Return a placeholder type.
333  return llvm::StructType::get(getLLVMContext());
334  }
335 
336  // While we're converting the parameter types for a function, we don't want
337  // to recursively convert any pointed-to structs. Converting directly-used
338  // structs is ok though.
339  if (!RecordsBeingLaidOut.insert(Ty).second) {
340  SkippedLayout = true;
341  return llvm::StructType::get(getLLVMContext());
342  }
343 
344  // The function type can be built; call the appropriate routines to
345  // build it.
346  const CGFunctionInfo *FI;
347  if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
350  } else {
351  const FunctionNoProtoType *FNPT = cast<FunctionNoProtoType>(FT);
354  }
355 
356  llvm::Type *ResultType = nullptr;
357  // If there is something higher level prodding our CGFunctionInfo, then
358  // don't recurse into it again.
359  if (FunctionsBeingProcessed.count(FI)) {
360 
361  ResultType = llvm::StructType::get(getLLVMContext());
362  SkippedLayout = true;
363  } else {
364 
365  // Otherwise, we're good to go, go ahead and convert it.
366  ResultType = GetFunctionType(*FI);
367  }
368 
369  RecordsBeingLaidOut.erase(Ty);
370 
371  if (SkippedLayout)
372  TypeCache.clear();
373 
374  if (RecordsBeingLaidOut.empty())
375  while (!DeferredRecords.empty())
376  ConvertRecordDeclType(DeferredRecords.pop_back_val());
377  return ResultType;
378 }
379 
380 /// ConvertType - Convert the specified type to its LLVM form.
382  T = Context.getCanonicalType(T);
383 
384  const Type *Ty = T.getTypePtr();
385 
386  // RecordTypes are cached and processed specially.
387  if (const RecordType *RT = dyn_cast<RecordType>(Ty))
388  return ConvertRecordDeclType(RT->getDecl());
389 
390  // See if type is already cached.
391  llvm::DenseMap<const Type *, llvm::Type *>::iterator TCI = TypeCache.find(Ty);
392  // If type is found in map then use it. Otherwise, convert type T.
393  if (TCI != TypeCache.end())
394  return TCI->second;
395 
396  // If we don't have it in the cache, convert it now.
397  llvm::Type *ResultType = nullptr;
398  switch (Ty->getTypeClass()) {
399  case Type::Record: // Handled above.
400 #define TYPE(Class, Base)
401 #define ABSTRACT_TYPE(Class, Base)
402 #define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
403 #define DEPENDENT_TYPE(Class, Base) case Type::Class:
404 #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
405 #include "clang/AST/TypeNodes.def"
406  llvm_unreachable("Non-canonical or dependent types aren't possible.");
407 
408  case Type::Builtin: {
409  switch (cast<BuiltinType>(Ty)->getKind()) {
410  case BuiltinType::Void:
411  case BuiltinType::ObjCId:
412  case BuiltinType::ObjCClass:
413  case BuiltinType::ObjCSel:
414  // LLVM void type can only be used as the result of a function call. Just
415  // map to the same as char.
416  ResultType = llvm::Type::getInt8Ty(getLLVMContext());
417  break;
418 
419  case BuiltinType::Bool:
420  // Note that we always return bool as i1 for use as a scalar type.
421  ResultType = llvm::Type::getInt1Ty(getLLVMContext());
422  break;
423 
424  case BuiltinType::Char_S:
425  case BuiltinType::Char_U:
426  case BuiltinType::SChar:
427  case BuiltinType::UChar:
428  case BuiltinType::Short:
429  case BuiltinType::UShort:
430  case BuiltinType::Int:
431  case BuiltinType::UInt:
432  case BuiltinType::Long:
433  case BuiltinType::ULong:
434  case BuiltinType::LongLong:
435  case BuiltinType::ULongLong:
436  case BuiltinType::WChar_S:
437  case BuiltinType::WChar_U:
438  case BuiltinType::Char8:
439  case BuiltinType::Char16:
440  case BuiltinType::Char32:
441  case BuiltinType::ShortAccum:
442  case BuiltinType::Accum:
443  case BuiltinType::LongAccum:
444  case BuiltinType::UShortAccum:
445  case BuiltinType::UAccum:
446  case BuiltinType::ULongAccum:
447  case BuiltinType::ShortFract:
448  case BuiltinType::Fract:
449  case BuiltinType::LongFract:
450  case BuiltinType::UShortFract:
451  case BuiltinType::UFract:
452  case BuiltinType::ULongFract:
453  case BuiltinType::SatShortAccum:
454  case BuiltinType::SatAccum:
455  case BuiltinType::SatLongAccum:
456  case BuiltinType::SatUShortAccum:
457  case BuiltinType::SatUAccum:
458  case BuiltinType::SatULongAccum:
459  case BuiltinType::SatShortFract:
460  case BuiltinType::SatFract:
461  case BuiltinType::SatLongFract:
462  case BuiltinType::SatUShortFract:
463  case BuiltinType::SatUFract:
464  case BuiltinType::SatULongFract:
465  ResultType = llvm::IntegerType::get(getLLVMContext(),
466  static_cast<unsigned>(Context.getTypeSize(T)));
467  break;
468 
469  case BuiltinType::Float16:
470  ResultType =
472  /* UseNativeHalf = */ true);
473  break;
474 
475  case BuiltinType::Half:
476  // Half FP can either be storage-only (lowered to i16) or native.
477  ResultType = getTypeForFormat(
479  Context.getLangOpts().NativeHalfType ||
481  break;
482  case BuiltinType::Float:
483  case BuiltinType::Double:
484  case BuiltinType::LongDouble:
485  case BuiltinType::Float128:
486  ResultType = getTypeForFormat(getLLVMContext(),
487  Context.getFloatTypeSemantics(T),
488  /* UseNativeHalf = */ false);
489  break;
490 
491  case BuiltinType::NullPtr:
492  // Model std::nullptr_t as i8*
493  ResultType = llvm::Type::getInt8PtrTy(getLLVMContext());
494  break;
495 
496  case BuiltinType::UInt128:
497  case BuiltinType::Int128:
498  ResultType = llvm::IntegerType::get(getLLVMContext(), 128);
499  break;
500 
501 #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
502  case BuiltinType::Id:
503 #include "clang/Basic/OpenCLImageTypes.def"
504 #define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
505  case BuiltinType::Id:
506 #include "clang/Basic/OpenCLExtensionTypes.def"
507  case BuiltinType::OCLSampler:
508  case BuiltinType::OCLEvent:
509  case BuiltinType::OCLClkEvent:
510  case BuiltinType::OCLQueue:
511  case BuiltinType::OCLReserveID:
512  ResultType = CGM.getOpenCLRuntime().convertOpenCLSpecificType(Ty);
513  break;
514 
515  case BuiltinType::Dependent:
516 #define BUILTIN_TYPE(Id, SingletonId)
517 #define PLACEHOLDER_TYPE(Id, SingletonId) \
518  case BuiltinType::Id:
519 #include "clang/AST/BuiltinTypes.def"
520  llvm_unreachable("Unexpected placeholder builtin type!");
521  }
522  break;
523  }
524  case Type::Auto:
525  case Type::DeducedTemplateSpecialization:
526  llvm_unreachable("Unexpected undeduced type!");
527  case Type::Complex: {
528  llvm::Type *EltTy = ConvertType(cast<ComplexType>(Ty)->getElementType());
529  ResultType = llvm::StructType::get(EltTy, EltTy);
530  break;
531  }
532  case Type::LValueReference:
533  case Type::RValueReference: {
534  const ReferenceType *RTy = cast<ReferenceType>(Ty);
535  QualType ETy = RTy->getPointeeType();
536  llvm::Type *PointeeType = ConvertTypeForMem(ETy);
537  unsigned AS = Context.getTargetAddressSpace(ETy);
538  ResultType = llvm::PointerType::get(PointeeType, AS);
539  break;
540  }
541  case Type::Pointer: {
542  const PointerType *PTy = cast<PointerType>(Ty);
543  QualType ETy = PTy->getPointeeType();
544  llvm::Type *PointeeType = ConvertTypeForMem(ETy);
545  if (PointeeType->isVoidTy())
546  PointeeType = llvm::Type::getInt8Ty(getLLVMContext());
547  unsigned AS = Context.getTargetAddressSpace(ETy);
548  ResultType = llvm::PointerType::get(PointeeType, AS);
549  break;
550  }
551 
552  case Type::VariableArray: {
553  const VariableArrayType *A = cast<VariableArrayType>(Ty);
554  assert(A->getIndexTypeCVRQualifiers() == 0 &&
555  "FIXME: We only handle trivial array types so far!");
556  // VLAs resolve to the innermost element type; this matches
557  // the return of alloca, and there isn't any obviously better choice.
558  ResultType = ConvertTypeForMem(A->getElementType());
559  break;
560  }
561  case Type::IncompleteArray: {
562  const IncompleteArrayType *A = cast<IncompleteArrayType>(Ty);
563  assert(A->getIndexTypeCVRQualifiers() == 0 &&
564  "FIXME: We only handle trivial array types so far!");
565  // int X[] -> [0 x int], unless the element type is not sized. If it is
566  // unsized (e.g. an incomplete struct) just use [0 x i8].
567  ResultType = ConvertTypeForMem(A->getElementType());
568  if (!ResultType->isSized()) {
569  SkippedLayout = true;
570  ResultType = llvm::Type::getInt8Ty(getLLVMContext());
571  }
572  ResultType = llvm::ArrayType::get(ResultType, 0);
573  break;
574  }
575  case Type::ConstantArray: {
576  const ConstantArrayType *A = cast<ConstantArrayType>(Ty);
578 
579  // Lower arrays of undefined struct type to arrays of i8 just to have a
580  // concrete type.
581  if (!EltTy->isSized()) {
582  SkippedLayout = true;
583  EltTy = llvm::Type::getInt8Ty(getLLVMContext());
584  }
585 
586  ResultType = llvm::ArrayType::get(EltTy, A->getSize().getZExtValue());
587  break;
588  }
589  case Type::ExtVector:
590  case Type::Vector: {
591  const VectorType *VT = cast<VectorType>(Ty);
592  ResultType = llvm::VectorType::get(ConvertType(VT->getElementType()),
593  VT->getNumElements());
594  break;
595  }
596  case Type::FunctionNoProto:
597  case Type::FunctionProto:
598  ResultType = ConvertFunctionTypeInternal(T);
599  break;
600  case Type::ObjCObject:
601  ResultType = ConvertType(cast<ObjCObjectType>(Ty)->getBaseType());
602  break;
603 
604  case Type::ObjCInterface: {
605  // Objective-C interfaces are always opaque (outside of the
606  // runtime, which can do whatever it likes); we never refine
607  // these.
608  llvm::Type *&T = InterfaceTypes[cast<ObjCInterfaceType>(Ty)];
609  if (!T)
611  ResultType = T;
612  break;
613  }
614 
615  case Type::ObjCObjectPointer: {
616  // Protocol qualifications do not influence the LLVM type, we just return a
617  // pointer to the underlying interface type. We don't need to worry about
618  // recursive conversion.
619  llvm::Type *T =
620  ConvertTypeForMem(cast<ObjCObjectPointerType>(Ty)->getPointeeType());
621  ResultType = T->getPointerTo();
622  break;
623  }
624 
625  case Type::Enum: {
626  const EnumDecl *ED = cast<EnumType>(Ty)->getDecl();
627  if (ED->isCompleteDefinition() || ED->isFixed())
628  return ConvertType(ED->getIntegerType());
629  // Return a placeholder 'i32' type. This can be changed later when the
630  // type is defined (see UpdateCompletedType), but is likely to be the
631  // "right" answer.
632  ResultType = llvm::Type::getInt32Ty(getLLVMContext());
633  break;
634  }
635 
636  case Type::BlockPointer: {
637  const QualType FTy = cast<BlockPointerType>(Ty)->getPointeeType();
638  llvm::Type *PointeeType = CGM.getLangOpts().OpenCL
640  : ConvertTypeForMem(FTy);
641  unsigned AS = Context.getTargetAddressSpace(FTy);
642  ResultType = llvm::PointerType::get(PointeeType, AS);
643  break;
644  }
645 
646  case Type::MemberPointer: {
647  auto *MPTy = cast<MemberPointerType>(Ty);
648  if (!getCXXABI().isMemberPointerConvertible(MPTy)) {
649  RecordsWithOpaqueMemberPointers.insert(MPTy->getClass());
651  } else {
652  ResultType = getCXXABI().ConvertMemberPointerType(MPTy);
653  }
654  break;
655  }
656 
657  case Type::Atomic: {
658  QualType valueType = cast<AtomicType>(Ty)->getValueType();
659  ResultType = ConvertTypeForMem(valueType);
660 
661  // Pad out to the inflated size if necessary.
662  uint64_t valueSize = Context.getTypeSize(valueType);
663  uint64_t atomicSize = Context.getTypeSize(Ty);
664  if (valueSize != atomicSize) {
665  assert(valueSize < atomicSize);
666  llvm::Type *elts[] = {
667  ResultType,
668  llvm::ArrayType::get(CGM.Int8Ty, (atomicSize - valueSize) / 8)
669  };
670  ResultType = llvm::StructType::get(getLLVMContext(),
671  llvm::makeArrayRef(elts));
672  }
673  break;
674  }
675  case Type::Pipe: {
676  ResultType = CGM.getOpenCLRuntime().getPipeType(cast<PipeType>(Ty));
677  break;
678  }
679  }
680 
681  assert(ResultType && "Didn't convert a type?");
682 
683  TypeCache[Ty] = ResultType;
684  return ResultType;
685 }
686 
688  return isPaddedAtomicType(type->castAs<AtomicType>());
689 }
690 
692  return Context.getTypeSize(type) != Context.getTypeSize(type->getValueType());
693 }
694 
695 /// ConvertRecordDeclType - Lay out a tagged decl type like struct or union.
696 llvm::StructType *CodeGenTypes::ConvertRecordDeclType(const RecordDecl *RD) {
697  // TagDecl's are not necessarily unique, instead use the (clang)
698  // type connected to the decl.
699  const Type *Key = Context.getTagDeclType(RD).getTypePtr();
700 
701  llvm::StructType *&Entry = RecordDeclTypes[Key];
702 
703  // If we don't have a StructType at all yet, create the forward declaration.
704  if (!Entry) {
706  addRecordTypeName(RD, Entry, "");
707  }
708  llvm::StructType *Ty = Entry;
709 
710  // If this is still a forward declaration, or the LLVM type is already
711  // complete, there's nothing more to do.
712  RD = RD->getDefinition();
713  if (!RD || !RD->isCompleteDefinition() || !Ty->isOpaque())
714  return Ty;
715 
716  // If converting this type would cause us to infinitely loop, don't do it!
717  if (!isSafeToConvert(RD, *this)) {
718  DeferredRecords.push_back(RD);
719  return Ty;
720  }
721 
722  // Okay, this is a definition of a type. Compile the implementation now.
723  bool InsertResult = RecordsBeingLaidOut.insert(Key).second;
724  (void)InsertResult;
725  assert(InsertResult && "Recursively compiling a struct?");
726 
727  // Force conversion of non-virtual base classes recursively.
728  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) {
729  for (const auto &I : CRD->bases()) {
730  if (I.isVirtual()) continue;
731 
732  ConvertRecordDeclType(I.getType()->getAs<RecordType>()->getDecl());
733  }
734  }
735 
736  // Layout fields.
737  CGRecordLayout *Layout = ComputeRecordLayout(RD, Ty);
738  CGRecordLayouts[Key] = Layout;
739 
740  // We're done laying out this struct.
741  bool EraseResult = RecordsBeingLaidOut.erase(Key); (void)EraseResult;
742  assert(EraseResult && "struct not in RecordsBeingLaidOut set?");
743 
744  // If this struct blocked a FunctionType conversion, then recompute whatever
745  // was derived from that.
746  // FIXME: This is hugely overconservative.
747  if (SkippedLayout)
748  TypeCache.clear();
749 
750  // If we're done converting the outer-most record, then convert any deferred
751  // structs as well.
752  if (RecordsBeingLaidOut.empty())
753  while (!DeferredRecords.empty())
754  ConvertRecordDeclType(DeferredRecords.pop_back_val());
755 
756  return Ty;
757 }
758 
759 /// getCGRecordLayout - Return record layout info for the given record decl.
760 const CGRecordLayout &
762  const Type *Key = Context.getTagDeclType(RD).getTypePtr();
763 
764  const CGRecordLayout *Layout = CGRecordLayouts.lookup(Key);
765  if (!Layout) {
766  // Compute the type information.
768 
769  // Now try again.
770  Layout = CGRecordLayouts.lookup(Key);
771  }
772 
773  assert(Layout && "Unable to find record layout information for type");
774  return *Layout;
775 }
776 
778  assert((T->isAnyPointerType() || T->isBlockPointerType()) && "Invalid type");
779  return isZeroInitializable(T);
780 }
781 
783  if (T->getAs<PointerType>())
784  return Context.getTargetNullPointerValue(T) == 0;
785 
786  if (const auto *AT = Context.getAsArrayType(T)) {
787  if (isa<IncompleteArrayType>(AT))
788  return true;
789  if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
790  if (Context.getConstantArrayElementCount(CAT) == 0)
791  return true;
792  T = Context.getBaseElementType(T);
793  }
794 
795  // Records are non-zero-initializable if they contain any
796  // non-zero-initializable subobjects.
797  if (const RecordType *RT = T->getAs<RecordType>()) {
798  const RecordDecl *RD = RT->getDecl();
799  return isZeroInitializable(RD);
800  }
801 
802  // We have to ask the ABI about member pointers.
803  if (const MemberPointerType *MPT = T->getAs<MemberPointerType>())
804  return getCXXABI().isZeroInitializable(MPT);
805 
806  // Everything else is okay.
807  return true;
808 }
809 
812 }
bool noRecordsBeingLaidOut() const
Definition: CodeGenTypes.h:306
CGCXXABI & getCXXABI() const
Definition: CodeGenTypes.h:119
CGOpenCLRuntime & getOpenCLRuntime()
Return a reference to the configured OpenCL runtime.
Defines the clang::ASTContext interface.
llvm::Type * getGenericBlockLiteralType()
The type of a generic block literal.
Definition: CGBlocks.cpp:1217
PointerType - C99 6.7.5.1 - Pointer Declarators.
Definition: Type.h:2554
QualType getPointeeType() const
Definition: Type.h:2567
A (possibly-)qualified type.
Definition: Type.h:643
bool isBlockPointerType() const
Definition: Type.h:6359
const CodeGenOptions & getCodeGenOpts() const
void UpdateCompletedType(const TagDecl *TD)
UpdateCompletedType - When we find the full definition for a TagDecl, replace the &#39;opaque&#39; type we pr...
CGRecordLayout - This class handles struct and union layout info while lowering AST types to LLVM typ...
static llvm::Type * getTypeForFormat(llvm::LLVMContext &VMContext, const llvm::fltSemantics &format, bool UseNativeHalf=false)
FunctionType - C99 6.7.5.3 - Function Declarators.
Definition: Type.h:3372
void addRecordTypeName(const RecordDecl *RD, llvm::StructType *Ty, StringRef suffix)
addRecordTypeName - Compute a name from the given record decl with an optional suffix and name the gi...
bool isRecordBeingLaidOut(const Type *Ty) const
Definition: CodeGenTypes.h:309
The base class of the type hierarchy.
Definition: Type.h:1418
const TargetInfo & getTargetInfo() const
Definition: ASTContext.h:693
QualType getValueType() const
Gets the type contained by this atomic type, i.e.
Definition: Type.h:6038
bool isFuncTypeConvertible(const FunctionType *FT)
isFuncTypeConvertible - Utility to check whether a function type can be converted to an LLVM type (i...
llvm::IntegerType * Int8Ty
i8, i16, i32, and i64
QualType getElementType() const
Definition: Type.h:2864
bool isCompleteDefinition() const
Return true if this decl has its body fully specified.
Definition: Decl.h:3200
bool isFixed() const
Returns true if this is an Objective-C, C++11, or Microsoft-style enumeration with a fixed underlying...
Definition: Decl.h:3560
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6818
CGDebugInfo * getModuleDebugInfo()
This class gathers all debug information during compilation and is responsible for emitting to llvm g...
Definition: CGDebugInfo.h:54
llvm::Type * ConvertTypeForMem(QualType T)
ConvertTypeForMem - Convert type T into a llvm::Type.
const CGFunctionInfo & arrangeFreeFunctionType(CanQual< FunctionProtoType > Ty)
Arrange the argument and result information for a value of the given freestanding function type...
Definition: CGCall.cpp:193
long i
Definition: xmmintrin.h:1456
IdentifierInfo * getIdentifier() const
Get the identifier that names this declaration, if there is one.
Definition: Decl.h:269
Represents a struct/union/class.
Definition: Decl.h:3624
llvm::Type * ConvertType(QualType T)
ConvertType - Convert type T into a llvm::Type.
RecordDecl * getDefinition() const
Returns the RecordDecl that actually defines this struct/union/class.
Definition: Decl.h:3805
field_range fields() const
Definition: Decl.h:3815
bool isPaddedAtomicType(QualType type)
static bool isSafeToConvert(QualType T, CodeGenTypes &CGT, llvm::SmallPtrSet< const RecordDecl *, 16 > &AlreadyChecked)
isSafeToConvert - Return true if it is safe to convert this field type, which requires the structure ...
uint64_t getConstantArrayElementCount(const ConstantArrayType *CA) const
Return number of constant array elements.
const Type * getTypePtr() const
Retrieves a pointer to the underlying (unqualified) type.
Definition: Type.h:6127
bool isZeroInitializable() const
Check whether this struct can be C++ zero-initialized with a zeroinitializer.
virtual llvm::Type * ConvertMemberPointerType(const MemberPointerType *MPT)
Find the LLVM type used to represent the given member pointer type.
Definition: CGCXXABI.cpp:36
virtual llvm::Type * getPipeType(const PipeType *T, StringRef Name, llvm::Type *&PipeTy)
virtual llvm::Type * convertOpenCLSpecificType(const Type *T)
virtual bool isZeroInitializable(const MemberPointerType *MPT)
Return true if the given member pointer can be zero-initialized (in the C++ sense) with an LLVM zeroi...
Definition: CGCXXABI.cpp:116
Represents a K&R-style &#39;int foo()&#39; function, which has no information available about its arguments...
Definition: Type.h:3667
Represents a prototype with parameter type info, e.g.
Definition: Type.h:3704
bool isPointerZeroInitializable(QualType T)
Check if the pointer type can be zero-initialized (in the C++ sense) with an LLVM zeroinitializer...
bool isDependentType() const
Whether this declaration declares a type that is dependent, i.e., a type that somehow depends on temp...
Definition: Decl.h:3251
CodeGenTypes(CodeGenModule &cgm)
StringRef getKindName() const
Definition: Decl.h:3270
QualType getPointeeType() const
Definition: Type.h:2711
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:6883
QualType getTagDeclType(const TagDecl *Decl) const
Return the unique reference to the type for the specified TagDecl (struct/union/class/enum) decl...
DeclContext * getDeclContext()
Definition: DeclBase.h:438
const CodeGenOptions & getCodeGenOpts() const
QualType getRecordType(const RecordDecl *Decl) const
Represents a GCC generic vector type.
Definition: Type.h:3185
void printQualifiedName(raw_ostream &OS) const
Returns a human-readable qualified name for this declaration, like A::B::i, for i being member of nam...
Definition: Decl.cpp:1555
const LangOptions & getLangOpts() const
The l-value was considered opaque, so the alignment was determined from a type.
RecordDecl * getDecl() const
Definition: Type.h:4433
virtual bool useFP16ConversionIntrinsics() const
Check whether llvm intrinsics such as llvm.convert.to.fp16 should be used to convert to and from __fp...
Definition: TargetInfo.h:749
virtual void printName(raw_ostream &os) const
Definition: Decl.cpp:1544
QualType getReturnType() const
Definition: Type.h:3630
Represents the declaration of a struct/union/class/enum.
Definition: Decl.h:3095
QualType getElementType() const
Definition: Type.h:3220
QualType getBaseElementType(const ArrayType *VAT) const
Return the innermost element type of an array type.
const ArrayType * getAsArrayType(QualType T) const
Type Query functions.
Represents a canonical, potentially-qualified type.
Definition: CanonicalType.h:65
bool isRecordLayoutComplete(const Type *Ty) const
isRecordLayoutComplete - Return true if the specified type is already completely laid out...
bool isAnyPointerType() const
Definition: Type.h:6355
llvm::LLVMContext & getLLVMContext()
Definition: CodeGenTypes.h:120
TypeClass getTypeClass() const
Definition: Type.h:1824
bool isCanonical() const
Definition: Type.h:6171
const llvm::fltSemantics & getFloatTypeSemantics(QualType T) const
Return the APFloat &#39;semantics&#39; for the specified scalar floating point type.
Base class for declarations which introduce a typedef-name.
Definition: Decl.h:2947
CGFunctionInfo - Class to encapsulate the information about a function definition.
This class organizes the cross-function state that is used while generating LLVM code.
Dataflow Directional Tag Classes.
std::unique_ptr< DiagnosticConsumer > create(StringRef OutputFile, DiagnosticOptions *Diags, bool MergeChildRecords=false)
Returns a DiagnosticConsumer that serializes diagnostics to a bitcode file.
virtual bool isMemberPointerConvertible(const MemberPointerType *MPT) const
Return whether or not a member pointers type is convertible to an IR type.
Definition: CGCXXABI.h:181
Represents an enum.
Definition: Decl.h:3357
A pointer to member type per C++ 8.3.3 - Pointers to members.
Definition: Type.h:2773
llvm::StructType * ConvertRecordDeclType(const RecordDecl *TD)
ConvertRecordDeclType - Lay out a tagged decl type like struct or union.
A helper class that allows the use of isa/cast/dyncast to detect TagType objects of structs/unions/cl...
Definition: Type.h:4423
unsigned getIndexTypeCVRQualifiers() const
Definition: Type.h:2874
const llvm::APInt & getSize() const
Definition: Type.h:2907
This class organizes the cross-module state that is used while lowering AST types to LLVM types...
Definition: CodeGenTypes.h:59
CodeGenOptions - Track various options which control how the code is optimized and passed to the back...
Base for LValueReferenceType and RValueReferenceType.
Definition: Type.h:2690
uint64_t getTypeSize(QualType T) const
Return the size of the specified (complete) type T, in bits.
Definition: ASTContext.h:2079
bool isIncompleteType(NamedDecl **Def=nullptr) const
Types are partitioned into 3 broad categories (C99 6.2.5p1): object types, function types...
Definition: Type.cpp:2062
ASTContext & getContext() const
Definition: CodeGenTypes.h:116
CanQualType getCanonicalType(QualType T) const
Return the canonical (structural) type corresponding to the specified potentially non-canonical type ...
Definition: ASTContext.h:2280
Defines the C++ Decl subclasses, other than those for templates (found in DeclTemplate.h) and friends (in DeclFriend.h).
TypedefNameDecl * getTypedefNameForAnonDecl() const
Definition: Decl.h:3305
Represents a C++ struct/union/class.
Definition: DeclCXX.h:300
Represents a C array with an unspecified size.
Definition: Type.h:2943
bool isFuncParamTypeConvertible(QualType Ty)
isFuncParamTypeConvertible - Return true if the specified type in a function parameter or result posi...
void RefreshTypeCacheForClass(const CXXRecordDecl *RD)
Remove stale types from the type cache when an inheritance model gets assigned to a class...
QualType getIntegerType() const
Return the integer type this enum decl corresponds to.
Definition: Decl.h:3511
static Decl::Kind getKind(const Decl *D)
Definition: DeclBase.cpp:943
unsigned getNumElements() const
Definition: Type.h:3221
uint64_t getTargetNullPointerValue(QualType QT) const
Get target-dependent integer value for null pointer which is used for constant folding.
CGRecordLayout * ComputeRecordLayout(const RecordDecl *D, llvm::StructType *Ty)
Compute a new LLVM record layout object for the given record.
Represents a C array with a specified size that is not an integer-constant-expression.
Definition: Type.h:2988
unsigned getTargetAddressSpace(QualType T) const
Definition: ASTContext.h:2532
const CGRecordLayout & getCGRecordLayout(const RecordDecl *)
getCGRecordLayout - Return record layout info for the given record decl.
const LangOptions & getLangOpts() const
Definition: ASTContext.h:710
Represents the canonical version of C arrays with a specified constant size.
Definition: Type.h:2889
bool isZeroInitializable(QualType T)
IsZeroInitializable - Return whether a type can be zero-initialized (in the C++ sense) with an LLVM z...
llvm::FunctionType * GetFunctionType(const CGFunctionInfo &Info)
GetFunctionType - Get the LLVM function type for.
Definition: CGCall.cpp:1541