1 //===--- CodeGenTypes.cpp - Type translation for LLVM CodeGen -------------===//
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
7 //===----------------------------------------------------------------------===//
9 // This is the code that handles AST -> LLVM type lowering.
11 //===----------------------------------------------------------------------===//
13 #include "CodeGenTypes.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"
24 #include "clang/CodeGen/CGFunctionInfo.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;
31 CodeGenTypes::CodeGenTypes(CodeGenModule &cgm)
32 : CGM(cgm), Context(cgm.getContext()), TheModule(cgm.getModule()),
33 Target(cgm.getTarget()), TheCXXABI(cgm.getCXXABI()),
34 TheABIInfo(cgm.getTargetCodeGenInfo().getABIInfo()) {
35 SkippedLayout = false;
38 CodeGenTypes::~CodeGenTypes() {
39 llvm::DeleteContainerSeconds(CGRecordLayouts);
41 for (llvm::FoldingSet<CGFunctionInfo>::iterator
42 I = FunctionInfos.begin(), E = FunctionInfos.end(); I != E; )
46 const CodeGenOptions &CodeGenTypes::getCodeGenOpts() const {
47 return CGM.getCodeGenOpts();
50 void CodeGenTypes::addRecordTypeName(const RecordDecl *RD,
53 SmallString<256> TypeName;
54 llvm::raw_svector_ostream OS(TypeName);
55 OS << RD->getKindName() << '.';
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);
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);
79 Ty->setName(OS.str());
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.
86 llvm::Type *CodeGenTypes::ConvertTypeForMem(QualType T) {
87 llvm::Type *R = ConvertType(T);
89 // If this is a non-bool type, don't map it.
90 if (!R->isIntegerTy(1))
93 // Otherwise, return an integer of the target-specified size.
94 return llvm::IntegerType::get(getLLVMContext(),
95 (unsigned)Context.getTypeSize(T));
99 /// isRecordLayoutComplete - Return true if the specified type is already
100 /// completely laid out.
101 bool CodeGenTypes::isRecordLayoutComplete(const Type *Ty) const {
102 llvm::DenseMap<const Type*, llvm::StructType *>::const_iterator I =
103 RecordDeclTypes.find(Ty);
104 return I != RecordDeclTypes.end() && !I->second->isOpaque();
108 isSafeToConvert(QualType T, CodeGenTypes &CGT,
109 llvm::SmallPtrSet<const RecordDecl*, 16> &AlreadyChecked);
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.
116 isSafeToConvert(const RecordDecl *RD, CodeGenTypes &CGT,
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)
123 const Type *Key = CGT.getContext().getTagDeclType(RD).getTypePtr();
125 // If this type is already laid out, converting it is a noop.
126 if (CGT.isRecordLayoutComplete(Key)) return true;
128 // If this type is currently being laid out, we can't recursively compile it.
129 if (CGT.isRecordBeingLaidOut(Key))
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
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))
143 // If this type would require laying out members that are currently being laid
145 for (const auto *I : RD->fields())
146 if (!isSafeToConvert(I->getType(), CGT, AlreadyChecked))
149 // If there are no problems, lets do it.
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.
157 isSafeToConvert(QualType T, CodeGenTypes &CGT,
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();
163 // If this is a record, check it.
164 if (const auto *RT = T->getAs<RecordType>())
165 return isSafeToConvert(RT->getDecl(), CGT, AlreadyChecked);
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);
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.
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;
185 llvm::SmallPtrSet<const RecordDecl*, 16> AlreadyChecked;
186 return isSafeToConvert(RD, CGT, AlreadyChecked);
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
194 bool CodeGenTypes::isFuncParamTypeConvertible(QualType Ty) {
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>())
198 return getCXXABI().isMemberPointerConvertible(MPT);
200 // If this isn't a tagged type, we can convert it!
201 const TagType *TT = Ty->getAs<TagType>();
202 if (!TT) return true;
204 // Incomplete types cannot be converted.
205 if (TT->isIncompleteType())
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;
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.
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);
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.
228 bool CodeGenTypes::isFuncTypeConvertible(const FunctionType *FT) {
229 if (!isFuncParamTypeConvertible(FT->getReturnType()))
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)))
240 /// UpdateCompletedType - When we find the full definition for a TagDecl,
241 /// replace the 'opaque' type we previously made for it if applicable.
242 void CodeGenTypes::UpdateCompletedType(const TagDecl *TD) {
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
252 if (!ConvertType(ED->getIntegerType())->isIntegerTy(32))
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);
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;
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()))
270 ConvertRecordDeclType(RD);
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);
278 void CodeGenTypes::RefreshTypeCacheForClass(const CXXRecordDecl *RD) {
279 QualType T = Context.getRecordType(RD);
280 T = Context.getCanonicalType(T);
282 const Type *Ty = T.getTypePtr();
283 if (RecordsWithOpaqueMemberPointers.count(Ty)) {
285 RecordsWithOpaqueMemberPointers.clear();
289 static llvm::Type *getTypeForFormat(llvm::LLVMContext &VMContext,
290 const llvm::fltSemantics &format,
291 bool UseNativeHalf = false) {
292 if (&format == &llvm::APFloat::IEEEhalf()) {
294 return llvm::Type::getHalfTy(VMContext);
296 return llvm::Type::getInt16Ty(VMContext);
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!");
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.
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());
330 SkippedLayout = true;
332 // Return a placeholder type.
333 return llvm::StructType::get(getLLVMContext());
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());
344 // The function type can be built; call the appropriate routines to
346 const CGFunctionInfo *FI;
347 if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FT)) {
348 FI = &arrangeFreeFunctionType(
349 CanQual<FunctionProtoType>::CreateUnsafe(QualType(FPT, 0)));
351 const FunctionNoProtoType *FNPT = cast<FunctionNoProtoType>(FT);
352 FI = &arrangeFreeFunctionType(
353 CanQual<FunctionNoProtoType>::CreateUnsafe(QualType(FNPT, 0)));
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)) {
361 ResultType = llvm::StructType::get(getLLVMContext());
362 SkippedLayout = true;
365 // Otherwise, we're good to go, go ahead and convert it.
366 ResultType = GetFunctionType(*FI);
369 RecordsBeingLaidOut.erase(Ty);
374 if (RecordsBeingLaidOut.empty())
375 while (!DeferredRecords.empty())
376 ConvertRecordDeclType(DeferredRecords.pop_back_val());
380 /// ConvertType - Convert the specified type to its LLVM form.
381 llvm::Type *CodeGenTypes::ConvertType(QualType T) {
382 T = Context.getCanonicalType(T);
384 const Type *Ty = T.getTypePtr();
386 // RecordTypes are cached and processed specially.
387 if (const RecordType *RT = dyn_cast<RecordType>(Ty))
388 return ConvertRecordDeclType(RT->getDecl());
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())
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.");
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());
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());
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)));
469 case BuiltinType::Float16:
471 getTypeForFormat(getLLVMContext(), Context.getFloatTypeSemantics(T),
472 /* UseNativeHalf = */ true);
475 case BuiltinType::Half:
476 // Half FP can either be storage-only (lowered to i16) or native.
477 ResultType = getTypeForFormat(
478 getLLVMContext(), Context.getFloatTypeSemantics(T),
479 Context.getLangOpts().NativeHalfType ||
480 !Context.getTargetInfo().useFP16ConversionIntrinsics());
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);
491 case BuiltinType::NullPtr:
492 // Model std::nullptr_t as i8*
493 ResultType = llvm::Type::getInt8PtrTy(getLLVMContext());
496 case BuiltinType::UInt128:
497 case BuiltinType::Int128:
498 ResultType = llvm::IntegerType::get(getLLVMContext(), 128);
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);
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!");
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);
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);
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);
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());
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());
572 ResultType = llvm::ArrayType::get(ResultType, 0);
575 case Type::ConstantArray: {
576 const ConstantArrayType *A = cast<ConstantArrayType>(Ty);
577 llvm::Type *EltTy = ConvertTypeForMem(A->getElementType());
579 // Lower arrays of undefined struct type to arrays of i8 just to have a
581 if (!EltTy->isSized()) {
582 SkippedLayout = true;
583 EltTy = llvm::Type::getInt8Ty(getLLVMContext());
586 ResultType = llvm::ArrayType::get(EltTy, A->getSize().getZExtValue());
589 case Type::ExtVector:
591 const VectorType *VT = cast<VectorType>(Ty);
592 ResultType = llvm::VectorType::get(ConvertType(VT->getElementType()),
593 VT->getNumElements());
596 case Type::FunctionNoProto:
597 case Type::FunctionProto:
598 ResultType = ConvertFunctionTypeInternal(T);
600 case Type::ObjCObject:
601 ResultType = ConvertType(cast<ObjCObjectType>(Ty)->getBaseType());
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
608 llvm::Type *&T = InterfaceTypes[cast<ObjCInterfaceType>(Ty)];
610 T = llvm::StructType::create(getLLVMContext());
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.
620 ConvertTypeForMem(cast<ObjCObjectPointerType>(Ty)->getPointeeType());
621 ResultType = T->getPointerTo();
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
632 ResultType = llvm::Type::getInt32Ty(getLLVMContext());
636 case Type::BlockPointer: {
637 const QualType FTy = cast<BlockPointerType>(Ty)->getPointeeType();
638 llvm::Type *PointeeType = CGM.getLangOpts().OpenCL
639 ? CGM.getGenericBlockLiteralType()
640 : ConvertTypeForMem(FTy);
641 unsigned AS = Context.getTargetAddressSpace(FTy);
642 ResultType = llvm::PointerType::get(PointeeType, AS);
646 case Type::MemberPointer: {
647 auto *MPTy = cast<MemberPointerType>(Ty);
648 if (!getCXXABI().isMemberPointerConvertible(MPTy)) {
649 RecordsWithOpaqueMemberPointers.insert(MPTy->getClass());
650 ResultType = llvm::StructType::create(getLLVMContext());
652 ResultType = getCXXABI().ConvertMemberPointerType(MPTy);
658 QualType valueType = cast<AtomicType>(Ty)->getValueType();
659 ResultType = ConvertTypeForMem(valueType);
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[] = {
668 llvm::ArrayType::get(CGM.Int8Ty, (atomicSize - valueSize) / 8)
670 ResultType = llvm::StructType::get(getLLVMContext(),
671 llvm::makeArrayRef(elts));
676 ResultType = CGM.getOpenCLRuntime().getPipeType(cast<PipeType>(Ty));
681 assert(ResultType && "Didn't convert a type?");
683 TypeCache[Ty] = ResultType;
687 bool CodeGenModule::isPaddedAtomicType(QualType type) {
688 return isPaddedAtomicType(type->castAs<AtomicType>());
691 bool CodeGenModule::isPaddedAtomicType(const AtomicType *type) {
692 return Context.getTypeSize(type) != Context.getTypeSize(type->getValueType());
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();
701 llvm::StructType *&Entry = RecordDeclTypes[Key];
703 // If we don't have a StructType at all yet, create the forward declaration.
705 Entry = llvm::StructType::create(getLLVMContext());
706 addRecordTypeName(RD, Entry, "");
708 llvm::StructType *Ty = Entry;
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())
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);
722 // Okay, this is a definition of a type. Compile the implementation now.
723 bool InsertResult = RecordsBeingLaidOut.insert(Key).second;
725 assert(InsertResult && "Recursively compiling a struct?");
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;
732 ConvertRecordDeclType(I.getType()->getAs<RecordType>()->getDecl());
737 CGRecordLayout *Layout = ComputeRecordLayout(RD, Ty);
738 CGRecordLayouts[Key] = Layout;
740 // We're done laying out this struct.
741 bool EraseResult = RecordsBeingLaidOut.erase(Key); (void)EraseResult;
742 assert(EraseResult && "struct not in RecordsBeingLaidOut set?");
744 // If this struct blocked a FunctionType conversion, then recompute whatever
745 // was derived from that.
746 // FIXME: This is hugely overconservative.
750 // If we're done converting the outer-most record, then convert any deferred
752 if (RecordsBeingLaidOut.empty())
753 while (!DeferredRecords.empty())
754 ConvertRecordDeclType(DeferredRecords.pop_back_val());
759 /// getCGRecordLayout - Return record layout info for the given record decl.
760 const CGRecordLayout &
761 CodeGenTypes::getCGRecordLayout(const RecordDecl *RD) {
762 const Type *Key = Context.getTagDeclType(RD).getTypePtr();
764 const CGRecordLayout *Layout = CGRecordLayouts.lookup(Key);
766 // Compute the type information.
767 ConvertRecordDeclType(RD);
770 Layout = CGRecordLayouts.lookup(Key);
773 assert(Layout && "Unable to find record layout information for type");
777 bool CodeGenTypes::isPointerZeroInitializable(QualType T) {
778 assert((T->isAnyPointerType() || T->isBlockPointerType()) && "Invalid type");
779 return isZeroInitializable(T);
782 bool CodeGenTypes::isZeroInitializable(QualType T) {
783 if (T->getAs<PointerType>())
784 return Context.getTargetNullPointerValue(T) == 0;
786 if (const auto *AT = Context.getAsArrayType(T)) {
787 if (isa<IncompleteArrayType>(AT))
789 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
790 if (Context.getConstantArrayElementCount(CAT) == 0)
792 T = Context.getBaseElementType(T);
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);
802 // We have to ask the ABI about member pointers.
803 if (const MemberPointerType *MPT = T->getAs<MemberPointerType>())
804 return getCXXABI().isZeroInitializable(MPT);
806 // Everything else is okay.
810 bool CodeGenTypes::isZeroInitializable(const RecordDecl *RD) {
811 return getCGRecordLayout(RD).isZeroInitializable();