Bug Summary

File:clang/lib/CodeGen/CGObjCGNU.cpp
Warning:line 2426, column 33
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name CGObjCGNU.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/CodeGen -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/CodeGen -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/lib/CodeGen -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/llvm/include -D NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-14/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/CodeGen -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-09-04-040900-46481-1 -x c++ /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/lib/CodeGen/CGObjCGNU.cpp

/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/lib/CodeGen/CGObjCGNU.cpp

1//===------- CGObjCGNU.cpp - Emit LLVM Code from ASTs for a Module --------===//
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 provides Objective-C code generation targeting the GNU runtime. The
10// class in this file generates structures used by the GNU Objective-C runtime
11// library. These structures are defined in objc/objc.h and objc/objc-api.h in
12// the GNU runtime distribution.
13//
14//===----------------------------------------------------------------------===//
15
16#include "CGCXXABI.h"
17#include "CGCleanup.h"
18#include "CGObjCRuntime.h"
19#include "CodeGenFunction.h"
20#include "CodeGenModule.h"
21#include "clang/AST/ASTContext.h"
22#include "clang/AST/Attr.h"
23#include "clang/AST/Decl.h"
24#include "clang/AST/DeclObjC.h"
25#include "clang/AST/RecordLayout.h"
26#include "clang/AST/StmtObjC.h"
27#include "clang/Basic/FileManager.h"
28#include "clang/Basic/SourceManager.h"
29#include "clang/CodeGen/ConstantInitBuilder.h"
30#include "llvm/ADT/SmallVector.h"
31#include "llvm/ADT/StringMap.h"
32#include "llvm/IR/DataLayout.h"
33#include "llvm/IR/Intrinsics.h"
34#include "llvm/IR/LLVMContext.h"
35#include "llvm/IR/Module.h"
36#include "llvm/Support/Compiler.h"
37#include "llvm/Support/ConvertUTF.h"
38#include <cctype>
39
40using namespace clang;
41using namespace CodeGen;
42
43namespace {
44
45/// Class that lazily initialises the runtime function. Avoids inserting the
46/// types and the function declaration into a module if they're not used, and
47/// avoids constructing the type more than once if it's used more than once.
48class LazyRuntimeFunction {
49 CodeGenModule *CGM;
50 llvm::FunctionType *FTy;
51 const char *FunctionName;
52 llvm::FunctionCallee Function;
53
54public:
55 /// Constructor leaves this class uninitialized, because it is intended to
56 /// be used as a field in another class and not all of the types that are
57 /// used as arguments will necessarily be available at construction time.
58 LazyRuntimeFunction()
59 : CGM(nullptr), FunctionName(nullptr), Function(nullptr) {}
60
61 /// Initialises the lazy function with the name, return type, and the types
62 /// of the arguments.
63 template <typename... Tys>
64 void init(CodeGenModule *Mod, const char *name, llvm::Type *RetTy,
65 Tys *... Types) {
66 CGM = Mod;
67 FunctionName = name;
68 Function = nullptr;
69 if(sizeof...(Tys)) {
70 SmallVector<llvm::Type *, 8> ArgTys({Types...});
71 FTy = llvm::FunctionType::get(RetTy, ArgTys, false);
72 }
73 else {
74 FTy = llvm::FunctionType::get(RetTy, None, false);
75 }
76 }
77
78 llvm::FunctionType *getType() { return FTy; }
79
80 /// Overloaded cast operator, allows the class to be implicitly cast to an
81 /// LLVM constant.
82 operator llvm::FunctionCallee() {
83 if (!Function) {
84 if (!FunctionName)
85 return nullptr;
86 Function = CGM->CreateRuntimeFunction(FTy, FunctionName);
87 }
88 return Function;
89 }
90};
91
92
93/// GNU Objective-C runtime code generation. This class implements the parts of
94/// Objective-C support that are specific to the GNU family of runtimes (GCC,
95/// GNUstep and ObjFW).
96class CGObjCGNU : public CGObjCRuntime {
97protected:
98 /// The LLVM module into which output is inserted
99 llvm::Module &TheModule;
100 /// strut objc_super. Used for sending messages to super. This structure
101 /// contains the receiver (object) and the expected class.
102 llvm::StructType *ObjCSuperTy;
103 /// struct objc_super*. The type of the argument to the superclass message
104 /// lookup functions.
105 llvm::PointerType *PtrToObjCSuperTy;
106 /// LLVM type for selectors. Opaque pointer (i8*) unless a header declaring
107 /// SEL is included in a header somewhere, in which case it will be whatever
108 /// type is declared in that header, most likely {i8*, i8*}.
109 llvm::PointerType *SelectorTy;
110 /// LLVM i8 type. Cached here to avoid repeatedly getting it in all of the
111 /// places where it's used
112 llvm::IntegerType *Int8Ty;
113 /// Pointer to i8 - LLVM type of char*, for all of the places where the
114 /// runtime needs to deal with C strings.
115 llvm::PointerType *PtrToInt8Ty;
116 /// struct objc_protocol type
117 llvm::StructType *ProtocolTy;
118 /// Protocol * type.
119 llvm::PointerType *ProtocolPtrTy;
120 /// Instance Method Pointer type. This is a pointer to a function that takes,
121 /// at a minimum, an object and a selector, and is the generic type for
122 /// Objective-C methods. Due to differences between variadic / non-variadic
123 /// calling conventions, it must always be cast to the correct type before
124 /// actually being used.
125 llvm::PointerType *IMPTy;
126 /// Type of an untyped Objective-C object. Clang treats id as a built-in type
127 /// when compiling Objective-C code, so this may be an opaque pointer (i8*),
128 /// but if the runtime header declaring it is included then it may be a
129 /// pointer to a structure.
130 llvm::PointerType *IdTy;
131 /// Pointer to a pointer to an Objective-C object. Used in the new ABI
132 /// message lookup function and some GC-related functions.
133 llvm::PointerType *PtrToIdTy;
134 /// The clang type of id. Used when using the clang CGCall infrastructure to
135 /// call Objective-C methods.
136 CanQualType ASTIdTy;
137 /// LLVM type for C int type.
138 llvm::IntegerType *IntTy;
139 /// LLVM type for an opaque pointer. This is identical to PtrToInt8Ty, but is
140 /// used in the code to document the difference between i8* meaning a pointer
141 /// to a C string and i8* meaning a pointer to some opaque type.
142 llvm::PointerType *PtrTy;
143 /// LLVM type for C long type. The runtime uses this in a lot of places where
144 /// it should be using intptr_t, but we can't fix this without breaking
145 /// compatibility with GCC...
146 llvm::IntegerType *LongTy;
147 /// LLVM type for C size_t. Used in various runtime data structures.
148 llvm::IntegerType *SizeTy;
149 /// LLVM type for C intptr_t.
150 llvm::IntegerType *IntPtrTy;
151 /// LLVM type for C ptrdiff_t. Mainly used in property accessor functions.
152 llvm::IntegerType *PtrDiffTy;
153 /// LLVM type for C int*. Used for GCC-ABI-compatible non-fragile instance
154 /// variables.
155 llvm::PointerType *PtrToIntTy;
156 /// LLVM type for Objective-C BOOL type.
157 llvm::Type *BoolTy;
158 /// 32-bit integer type, to save us needing to look it up every time it's used.
159 llvm::IntegerType *Int32Ty;
160 /// 64-bit integer type, to save us needing to look it up every time it's used.
161 llvm::IntegerType *Int64Ty;
162 /// The type of struct objc_property.
163 llvm::StructType *PropertyMetadataTy;
164 /// Metadata kind used to tie method lookups to message sends. The GNUstep
165 /// runtime provides some LLVM passes that can use this to do things like
166 /// automatic IMP caching and speculative inlining.
167 unsigned msgSendMDKind;
168 /// Does the current target use SEH-based exceptions? False implies
169 /// Itanium-style DWARF unwinding.
170 bool usesSEHExceptions;
171
172 /// Helper to check if we are targeting a specific runtime version or later.
173 bool isRuntime(ObjCRuntime::Kind kind, unsigned major, unsigned minor=0) {
174 const ObjCRuntime &R = CGM.getLangOpts().ObjCRuntime;
175 return (R.getKind() == kind) &&
176 (R.getVersion() >= VersionTuple(major, minor));
177 }
178
179 std::string ManglePublicSymbol(StringRef Name) {
180 return (StringRef(CGM.getTriple().isOSBinFormatCOFF() ? "$_" : "._") + Name).str();
181 }
182
183 std::string SymbolForProtocol(Twine Name) {
184 return (ManglePublicSymbol("OBJC_PROTOCOL_") + Name).str();
185 }
186
187 std::string SymbolForProtocolRef(StringRef Name) {
188 return (ManglePublicSymbol("OBJC_REF_PROTOCOL_") + Name).str();
189 }
190
191
192 /// Helper function that generates a constant string and returns a pointer to
193 /// the start of the string. The result of this function can be used anywhere
194 /// where the C code specifies const char*.
195 llvm::Constant *MakeConstantString(StringRef Str, const char *Name = "") {
196 ConstantAddress Array =
197 CGM.GetAddrOfConstantCString(std::string(Str), Name);
198 return llvm::ConstantExpr::getGetElementPtr(Array.getElementType(),
199 Array.getPointer(), Zeros);
200 }
201
202 /// Emits a linkonce_odr string, whose name is the prefix followed by the
203 /// string value. This allows the linker to combine the strings between
204 /// different modules. Used for EH typeinfo names, selector strings, and a
205 /// few other things.
206 llvm::Constant *ExportUniqueString(const std::string &Str,
207 const std::string &prefix,
208 bool Private=false) {
209 std::string name = prefix + Str;
210 auto *ConstStr = TheModule.getGlobalVariable(name);
211 if (!ConstStr) {
212 llvm::Constant *value = llvm::ConstantDataArray::getString(VMContext,Str);
213 auto *GV = new llvm::GlobalVariable(TheModule, value->getType(), true,
214 llvm::GlobalValue::LinkOnceODRLinkage, value, name);
215 GV->setComdat(TheModule.getOrInsertComdat(name));
216 if (Private)
217 GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
218 ConstStr = GV;
219 }
220 return llvm::ConstantExpr::getGetElementPtr(ConstStr->getValueType(),
221 ConstStr, Zeros);
222 }
223
224 /// Returns a property name and encoding string.
225 llvm::Constant *MakePropertyEncodingString(const ObjCPropertyDecl *PD,
226 const Decl *Container) {
227 assert(!isRuntime(ObjCRuntime::GNUstep, 2))(static_cast<void> (0));
228 if (isRuntime(ObjCRuntime::GNUstep, 1, 6)) {
229 std::string NameAndAttributes;
230 std::string TypeStr =
231 CGM.getContext().getObjCEncodingForPropertyDecl(PD, Container);
232 NameAndAttributes += '\0';
233 NameAndAttributes += TypeStr.length() + 3;
234 NameAndAttributes += TypeStr;
235 NameAndAttributes += '\0';
236 NameAndAttributes += PD->getNameAsString();
237 return MakeConstantString(NameAndAttributes);
238 }
239 return MakeConstantString(PD->getNameAsString());
240 }
241
242 /// Push the property attributes into two structure fields.
243 void PushPropertyAttributes(ConstantStructBuilder &Fields,
244 const ObjCPropertyDecl *property, bool isSynthesized=true, bool
245 isDynamic=true) {
246 int attrs = property->getPropertyAttributes();
247 // For read-only properties, clear the copy and retain flags
248 if (attrs & ObjCPropertyAttribute::kind_readonly) {
249 attrs &= ~ObjCPropertyAttribute::kind_copy;
250 attrs &= ~ObjCPropertyAttribute::kind_retain;
251 attrs &= ~ObjCPropertyAttribute::kind_weak;
252 attrs &= ~ObjCPropertyAttribute::kind_strong;
253 }
254 // The first flags field has the same attribute values as clang uses internally
255 Fields.addInt(Int8Ty, attrs & 0xff);
256 attrs >>= 8;
257 attrs <<= 2;
258 // For protocol properties, synthesized and dynamic have no meaning, so we
259 // reuse these flags to indicate that this is a protocol property (both set
260 // has no meaning, as a property can't be both synthesized and dynamic)
261 attrs |= isSynthesized ? (1<<0) : 0;
262 attrs |= isDynamic ? (1<<1) : 0;
263 // The second field is the next four fields left shifted by two, with the
264 // low bit set to indicate whether the field is synthesized or dynamic.
265 Fields.addInt(Int8Ty, attrs & 0xff);
266 // Two padding fields
267 Fields.addInt(Int8Ty, 0);
268 Fields.addInt(Int8Ty, 0);
269 }
270
271 virtual llvm::Constant *GenerateCategoryProtocolList(const
272 ObjCCategoryDecl *OCD);
273 virtual ConstantArrayBuilder PushPropertyListHeader(ConstantStructBuilder &Fields,
274 int count) {
275 // int count;
276 Fields.addInt(IntTy, count);
277 // int size; (only in GNUstep v2 ABI.
278 if (isRuntime(ObjCRuntime::GNUstep, 2)) {
279 llvm::DataLayout td(&TheModule);
280 Fields.addInt(IntTy, td.getTypeSizeInBits(PropertyMetadataTy) /
281 CGM.getContext().getCharWidth());
282 }
283 // struct objc_property_list *next;
284 Fields.add(NULLPtr);
285 // struct objc_property properties[]
286 return Fields.beginArray(PropertyMetadataTy);
287 }
288 virtual void PushProperty(ConstantArrayBuilder &PropertiesArray,
289 const ObjCPropertyDecl *property,
290 const Decl *OCD,
291 bool isSynthesized=true, bool
292 isDynamic=true) {
293 auto Fields = PropertiesArray.beginStruct(PropertyMetadataTy);
294 ASTContext &Context = CGM.getContext();
295 Fields.add(MakePropertyEncodingString(property, OCD));
296 PushPropertyAttributes(Fields, property, isSynthesized, isDynamic);
297 auto addPropertyMethod = [&](const ObjCMethodDecl *accessor) {
298 if (accessor) {
299 std::string TypeStr = Context.getObjCEncodingForMethodDecl(accessor);
300 llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
301 Fields.add(MakeConstantString(accessor->getSelector().getAsString()));
302 Fields.add(TypeEncoding);
303 } else {
304 Fields.add(NULLPtr);
305 Fields.add(NULLPtr);
306 }
307 };
308 addPropertyMethod(property->getGetterMethodDecl());
309 addPropertyMethod(property->getSetterMethodDecl());
310 Fields.finishAndAddTo(PropertiesArray);
311 }
312
313 /// Ensures that the value has the required type, by inserting a bitcast if
314 /// required. This function lets us avoid inserting bitcasts that are
315 /// redundant.
316 llvm::Value* EnforceType(CGBuilderTy &B, llvm::Value *V, llvm::Type *Ty) {
317 if (V->getType() == Ty) return V;
318 return B.CreateBitCast(V, Ty);
319 }
320 Address EnforceType(CGBuilderTy &B, Address V, llvm::Type *Ty) {
321 if (V.getType() == Ty) return V;
322 return B.CreateBitCast(V, Ty);
323 }
324
325 // Some zeros used for GEPs in lots of places.
326 llvm::Constant *Zeros[2];
327 /// Null pointer value. Mainly used as a terminator in various arrays.
328 llvm::Constant *NULLPtr;
329 /// LLVM context.
330 llvm::LLVMContext &VMContext;
331
332protected:
333
334 /// Placeholder for the class. Lots of things refer to the class before we've
335 /// actually emitted it. We use this alias as a placeholder, and then replace
336 /// it with a pointer to the class structure before finally emitting the
337 /// module.
338 llvm::GlobalAlias *ClassPtrAlias;
339 /// Placeholder for the metaclass. Lots of things refer to the class before
340 /// we've / actually emitted it. We use this alias as a placeholder, and then
341 /// replace / it with a pointer to the metaclass structure before finally
342 /// emitting the / module.
343 llvm::GlobalAlias *MetaClassPtrAlias;
344 /// All of the classes that have been generated for this compilation units.
345 std::vector<llvm::Constant*> Classes;
346 /// All of the categories that have been generated for this compilation units.
347 std::vector<llvm::Constant*> Categories;
348 /// All of the Objective-C constant strings that have been generated for this
349 /// compilation units.
350 std::vector<llvm::Constant*> ConstantStrings;
351 /// Map from string values to Objective-C constant strings in the output.
352 /// Used to prevent emitting Objective-C strings more than once. This should
353 /// not be required at all - CodeGenModule should manage this list.
354 llvm::StringMap<llvm::Constant*> ObjCStrings;
355 /// All of the protocols that have been declared.
356 llvm::StringMap<llvm::Constant*> ExistingProtocols;
357 /// For each variant of a selector, we store the type encoding and a
358 /// placeholder value. For an untyped selector, the type will be the empty
359 /// string. Selector references are all done via the module's selector table,
360 /// so we create an alias as a placeholder and then replace it with the real
361 /// value later.
362 typedef std::pair<std::string, llvm::GlobalAlias*> TypedSelector;
363 /// Type of the selector map. This is roughly equivalent to the structure
364 /// used in the GNUstep runtime, which maintains a list of all of the valid
365 /// types for a selector in a table.
366 typedef llvm::DenseMap<Selector, SmallVector<TypedSelector, 2> >
367 SelectorMap;
368 /// A map from selectors to selector types. This allows us to emit all
369 /// selectors of the same name and type together.
370 SelectorMap SelectorTable;
371
372 /// Selectors related to memory management. When compiling in GC mode, we
373 /// omit these.
374 Selector RetainSel, ReleaseSel, AutoreleaseSel;
375 /// Runtime functions used for memory management in GC mode. Note that clang
376 /// supports code generation for calling these functions, but neither GNU
377 /// runtime actually supports this API properly yet.
378 LazyRuntimeFunction IvarAssignFn, StrongCastAssignFn, MemMoveFn, WeakReadFn,
379 WeakAssignFn, GlobalAssignFn;
380
381 typedef std::pair<std::string, std::string> ClassAliasPair;
382 /// All classes that have aliases set for them.
383 std::vector<ClassAliasPair> ClassAliases;
384
385protected:
386 /// Function used for throwing Objective-C exceptions.
387 LazyRuntimeFunction ExceptionThrowFn;
388 /// Function used for rethrowing exceptions, used at the end of \@finally or
389 /// \@synchronize blocks.
390 LazyRuntimeFunction ExceptionReThrowFn;
391 /// Function called when entering a catch function. This is required for
392 /// differentiating Objective-C exceptions and foreign exceptions.
393 LazyRuntimeFunction EnterCatchFn;
394 /// Function called when exiting from a catch block. Used to do exception
395 /// cleanup.
396 LazyRuntimeFunction ExitCatchFn;
397 /// Function called when entering an \@synchronize block. Acquires the lock.
398 LazyRuntimeFunction SyncEnterFn;
399 /// Function called when exiting an \@synchronize block. Releases the lock.
400 LazyRuntimeFunction SyncExitFn;
401
402private:
403 /// Function called if fast enumeration detects that the collection is
404 /// modified during the update.
405 LazyRuntimeFunction EnumerationMutationFn;
406 /// Function for implementing synthesized property getters that return an
407 /// object.
408 LazyRuntimeFunction GetPropertyFn;
409 /// Function for implementing synthesized property setters that return an
410 /// object.
411 LazyRuntimeFunction SetPropertyFn;
412 /// Function used for non-object declared property getters.
413 LazyRuntimeFunction GetStructPropertyFn;
414 /// Function used for non-object declared property setters.
415 LazyRuntimeFunction SetStructPropertyFn;
416
417protected:
418 /// The version of the runtime that this class targets. Must match the
419 /// version in the runtime.
420 int RuntimeVersion;
421 /// The version of the protocol class. Used to differentiate between ObjC1
422 /// and ObjC2 protocols. Objective-C 1 protocols can not contain optional
423 /// components and can not contain declared properties. We always emit
424 /// Objective-C 2 property structures, but we have to pretend that they're
425 /// Objective-C 1 property structures when targeting the GCC runtime or it
426 /// will abort.
427 const int ProtocolVersion;
428 /// The version of the class ABI. This value is used in the class structure
429 /// and indicates how various fields should be interpreted.
430 const int ClassABIVersion;
431 /// Generates an instance variable list structure. This is a structure
432 /// containing a size and an array of structures containing instance variable
433 /// metadata. This is used purely for introspection in the fragile ABI. In
434 /// the non-fragile ABI, it's used for instance variable fixup.
435 virtual llvm::Constant *GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames,
436 ArrayRef<llvm::Constant *> IvarTypes,
437 ArrayRef<llvm::Constant *> IvarOffsets,
438 ArrayRef<llvm::Constant *> IvarAlign,
439 ArrayRef<Qualifiers::ObjCLifetime> IvarOwnership);
440
441 /// Generates a method list structure. This is a structure containing a size
442 /// and an array of structures containing method metadata.
443 ///
444 /// This structure is used by both classes and categories, and contains a next
445 /// pointer allowing them to be chained together in a linked list.
446 llvm::Constant *GenerateMethodList(StringRef ClassName,
447 StringRef CategoryName,
448 ArrayRef<const ObjCMethodDecl*> Methods,
449 bool isClassMethodList);
450
451 /// Emits an empty protocol. This is used for \@protocol() where no protocol
452 /// is found. The runtime will (hopefully) fix up the pointer to refer to the
453 /// real protocol.
454 virtual llvm::Constant *GenerateEmptyProtocol(StringRef ProtocolName);
455
456 /// Generates a list of property metadata structures. This follows the same
457 /// pattern as method and instance variable metadata lists.
458 llvm::Constant *GeneratePropertyList(const Decl *Container,
459 const ObjCContainerDecl *OCD,
460 bool isClassProperty=false,
461 bool protocolOptionalProperties=false);
462
463 /// Generates a list of referenced protocols. Classes, categories, and
464 /// protocols all use this structure.
465 llvm::Constant *GenerateProtocolList(ArrayRef<std::string> Protocols);
466
467 /// To ensure that all protocols are seen by the runtime, we add a category on
468 /// a class defined in the runtime, declaring no methods, but adopting the
469 /// protocols. This is a horribly ugly hack, but it allows us to collect all
470 /// of the protocols without changing the ABI.
471 void GenerateProtocolHolderCategory();
472
473 /// Generates a class structure.
474 llvm::Constant *GenerateClassStructure(
475 llvm::Constant *MetaClass,
476 llvm::Constant *SuperClass,
477 unsigned info,
478 const char *Name,
479 llvm::Constant *Version,
480 llvm::Constant *InstanceSize,
481 llvm::Constant *IVars,
482 llvm::Constant *Methods,
483 llvm::Constant *Protocols,
484 llvm::Constant *IvarOffsets,
485 llvm::Constant *Properties,
486 llvm::Constant *StrongIvarBitmap,
487 llvm::Constant *WeakIvarBitmap,
488 bool isMeta=false);
489
490 /// Generates a method list. This is used by protocols to define the required
491 /// and optional methods.
492 virtual llvm::Constant *GenerateProtocolMethodList(
493 ArrayRef<const ObjCMethodDecl*> Methods);
494 /// Emits optional and required method lists.
495 template<class T>
496 void EmitProtocolMethodList(T &&Methods, llvm::Constant *&Required,
497 llvm::Constant *&Optional) {
498 SmallVector<const ObjCMethodDecl*, 16> RequiredMethods;
499 SmallVector<const ObjCMethodDecl*, 16> OptionalMethods;
500 for (const auto *I : Methods)
501 if (I->isOptional())
502 OptionalMethods.push_back(I);
503 else
504 RequiredMethods.push_back(I);
505 Required = GenerateProtocolMethodList(RequiredMethods);
506 Optional = GenerateProtocolMethodList(OptionalMethods);
507 }
508
509 /// Returns a selector with the specified type encoding. An empty string is
510 /// used to return an untyped selector (with the types field set to NULL).
511 virtual llvm::Value *GetTypedSelector(CodeGenFunction &CGF, Selector Sel,
512 const std::string &TypeEncoding);
513
514 /// Returns the name of ivar offset variables. In the GNUstep v1 ABI, this
515 /// contains the class and ivar names, in the v2 ABI this contains the type
516 /// encoding as well.
517 virtual std::string GetIVarOffsetVariableName(const ObjCInterfaceDecl *ID,
518 const ObjCIvarDecl *Ivar) {
519 const std::string Name = "__objc_ivar_offset_" + ID->getNameAsString()
520 + '.' + Ivar->getNameAsString();
521 return Name;
522 }
523 /// Returns the variable used to store the offset of an instance variable.
524 llvm::GlobalVariable *ObjCIvarOffsetVariable(const ObjCInterfaceDecl *ID,
525 const ObjCIvarDecl *Ivar);
526 /// Emits a reference to a class. This allows the linker to object if there
527 /// is no class of the matching name.
528 void EmitClassRef(const std::string &className);
529
530 /// Emits a pointer to the named class
531 virtual llvm::Value *GetClassNamed(CodeGenFunction &CGF,
532 const std::string &Name, bool isWeak);
533
534 /// Looks up the method for sending a message to the specified object. This
535 /// mechanism differs between the GCC and GNU runtimes, so this method must be
536 /// overridden in subclasses.
537 virtual llvm::Value *LookupIMP(CodeGenFunction &CGF,
538 llvm::Value *&Receiver,
539 llvm::Value *cmd,
540 llvm::MDNode *node,
541 MessageSendInfo &MSI) = 0;
542
543 /// Looks up the method for sending a message to a superclass. This
544 /// mechanism differs between the GCC and GNU runtimes, so this method must
545 /// be overridden in subclasses.
546 virtual llvm::Value *LookupIMPSuper(CodeGenFunction &CGF,
547 Address ObjCSuper,
548 llvm::Value *cmd,
549 MessageSendInfo &MSI) = 0;
550
551 /// Libobjc2 uses a bitfield representation where small(ish) bitfields are
552 /// stored in a 64-bit value with the low bit set to 1 and the remaining 63
553 /// bits set to their values, LSB first, while larger ones are stored in a
554 /// structure of this / form:
555 ///
556 /// struct { int32_t length; int32_t values[length]; };
557 ///
558 /// The values in the array are stored in host-endian format, with the least
559 /// significant bit being assumed to come first in the bitfield. Therefore,
560 /// a bitfield with the 64th bit set will be (int64_t)&{ 2, [0, 1<<31] },
561 /// while a bitfield / with the 63rd bit set will be 1<<64.
562 llvm::Constant *MakeBitField(ArrayRef<bool> bits);
563
564public:
565 CGObjCGNU(CodeGenModule &cgm, unsigned runtimeABIVersion,
566 unsigned protocolClassVersion, unsigned classABI=1);
567
568 ConstantAddress GenerateConstantString(const StringLiteral *) override;
569
570 RValue
571 GenerateMessageSend(CodeGenFunction &CGF, ReturnValueSlot Return,
572 QualType ResultType, Selector Sel,
573 llvm::Value *Receiver, const CallArgList &CallArgs,
574 const ObjCInterfaceDecl *Class,
575 const ObjCMethodDecl *Method) override;
576 RValue
577 GenerateMessageSendSuper(CodeGenFunction &CGF, ReturnValueSlot Return,
578 QualType ResultType, Selector Sel,
579 const ObjCInterfaceDecl *Class,
580 bool isCategoryImpl, llvm::Value *Receiver,
581 bool IsClassMessage, const CallArgList &CallArgs,
582 const ObjCMethodDecl *Method) override;
583 llvm::Value *GetClass(CodeGenFunction &CGF,
584 const ObjCInterfaceDecl *OID) override;
585 llvm::Value *GetSelector(CodeGenFunction &CGF, Selector Sel) override;
586 Address GetAddrOfSelector(CodeGenFunction &CGF, Selector Sel) override;
587 llvm::Value *GetSelector(CodeGenFunction &CGF,
588 const ObjCMethodDecl *Method) override;
589 virtual llvm::Constant *GetConstantSelector(Selector Sel,
590 const std::string &TypeEncoding) {
591 llvm_unreachable("Runtime unable to generate constant selector")__builtin_unreachable();
592 }
593 llvm::Constant *GetConstantSelector(const ObjCMethodDecl *M) {
594 return GetConstantSelector(M->getSelector(),
595 CGM.getContext().getObjCEncodingForMethodDecl(M));
596 }
597 llvm::Constant *GetEHType(QualType T) override;
598
599 llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD,
600 const ObjCContainerDecl *CD) override;
601 void GenerateDirectMethodPrologue(CodeGenFunction &CGF, llvm::Function *Fn,
602 const ObjCMethodDecl *OMD,
603 const ObjCContainerDecl *CD) override;
604 void GenerateCategory(const ObjCCategoryImplDecl *CMD) override;
605 void GenerateClass(const ObjCImplementationDecl *ClassDecl) override;
606 void RegisterAlias(const ObjCCompatibleAliasDecl *OAD) override;
607 llvm::Value *GenerateProtocolRef(CodeGenFunction &CGF,
608 const ObjCProtocolDecl *PD) override;
609 void GenerateProtocol(const ObjCProtocolDecl *PD) override;
610
611 virtual llvm::Constant *GenerateProtocolRef(const ObjCProtocolDecl *PD);
612
613 llvm::Constant *GetOrEmitProtocol(const ObjCProtocolDecl *PD) override {
614 return GenerateProtocolRef(PD);
615 }
616
617 llvm::Function *ModuleInitFunction() override;
618 llvm::FunctionCallee GetPropertyGetFunction() override;
619 llvm::FunctionCallee GetPropertySetFunction() override;
620 llvm::FunctionCallee GetOptimizedPropertySetFunction(bool atomic,
621 bool copy) override;
622 llvm::FunctionCallee GetSetStructFunction() override;
623 llvm::FunctionCallee GetGetStructFunction() override;
624 llvm::FunctionCallee GetCppAtomicObjectGetFunction() override;
625 llvm::FunctionCallee GetCppAtomicObjectSetFunction() override;
626 llvm::FunctionCallee EnumerationMutationFunction() override;
627
628 void EmitTryStmt(CodeGenFunction &CGF,
629 const ObjCAtTryStmt &S) override;
630 void EmitSynchronizedStmt(CodeGenFunction &CGF,
631 const ObjCAtSynchronizedStmt &S) override;
632 void EmitThrowStmt(CodeGenFunction &CGF,
633 const ObjCAtThrowStmt &S,
634 bool ClearInsertionPoint=true) override;
635 llvm::Value * EmitObjCWeakRead(CodeGenFunction &CGF,
636 Address AddrWeakObj) override;
637 void EmitObjCWeakAssign(CodeGenFunction &CGF,
638 llvm::Value *src, Address dst) override;
639 void EmitObjCGlobalAssign(CodeGenFunction &CGF,
640 llvm::Value *src, Address dest,
641 bool threadlocal=false) override;
642 void EmitObjCIvarAssign(CodeGenFunction &CGF, llvm::Value *src,
643 Address dest, llvm::Value *ivarOffset) override;
644 void EmitObjCStrongCastAssign(CodeGenFunction &CGF,
645 llvm::Value *src, Address dest) override;
646 void EmitGCMemmoveCollectable(CodeGenFunction &CGF, Address DestPtr,
647 Address SrcPtr,
648 llvm::Value *Size) override;
649 LValue EmitObjCValueForIvar(CodeGenFunction &CGF, QualType ObjectTy,
650 llvm::Value *BaseValue, const ObjCIvarDecl *Ivar,
651 unsigned CVRQualifiers) override;
652 llvm::Value *EmitIvarOffset(CodeGenFunction &CGF,
653 const ObjCInterfaceDecl *Interface,
654 const ObjCIvarDecl *Ivar) override;
655 llvm::Value *EmitNSAutoreleasePoolClassRef(CodeGenFunction &CGF) override;
656 llvm::Constant *BuildGCBlockLayout(CodeGenModule &CGM,
657 const CGBlockInfo &blockInfo) override {
658 return NULLPtr;
659 }
660 llvm::Constant *BuildRCBlockLayout(CodeGenModule &CGM,
661 const CGBlockInfo &blockInfo) override {
662 return NULLPtr;
663 }
664
665 llvm::Constant *BuildByrefLayout(CodeGenModule &CGM, QualType T) override {
666 return NULLPtr;
667 }
668};
669
670/// Class representing the legacy GCC Objective-C ABI. This is the default when
671/// -fobjc-nonfragile-abi is not specified.
672///
673/// The GCC ABI target actually generates code that is approximately compatible
674/// with the new GNUstep runtime ABI, but refrains from using any features that
675/// would not work with the GCC runtime. For example, clang always generates
676/// the extended form of the class structure, and the extra fields are simply
677/// ignored by GCC libobjc.
678class CGObjCGCC : public CGObjCGNU {
679 /// The GCC ABI message lookup function. Returns an IMP pointing to the
680 /// method implementation for this message.
681 LazyRuntimeFunction MsgLookupFn;
682 /// The GCC ABI superclass message lookup function. Takes a pointer to a
683 /// structure describing the receiver and the class, and a selector as
684 /// arguments. Returns the IMP for the corresponding method.
685 LazyRuntimeFunction MsgLookupSuperFn;
686
687protected:
688 llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver,
689 llvm::Value *cmd, llvm::MDNode *node,
690 MessageSendInfo &MSI) override {
691 CGBuilderTy &Builder = CGF.Builder;
692 llvm::Value *args[] = {
693 EnforceType(Builder, Receiver, IdTy),
694 EnforceType(Builder, cmd, SelectorTy) };
695 llvm::CallBase *imp = CGF.EmitRuntimeCallOrInvoke(MsgLookupFn, args);
696 imp->setMetadata(msgSendMDKind, node);
697 return imp;
698 }
699
700 llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, Address ObjCSuper,
701 llvm::Value *cmd, MessageSendInfo &MSI) override {
702 CGBuilderTy &Builder = CGF.Builder;
703 llvm::Value *lookupArgs[] = {EnforceType(Builder, ObjCSuper,
704 PtrToObjCSuperTy).getPointer(), cmd};
705 return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFn, lookupArgs);
706 }
707
708public:
709 CGObjCGCC(CodeGenModule &Mod) : CGObjCGNU(Mod, 8, 2) {
710 // IMP objc_msg_lookup(id, SEL);
711 MsgLookupFn.init(&CGM, "objc_msg_lookup", IMPTy, IdTy, SelectorTy);
712 // IMP objc_msg_lookup_super(struct objc_super*, SEL);
713 MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy,
714 PtrToObjCSuperTy, SelectorTy);
715 }
716};
717
718/// Class used when targeting the new GNUstep runtime ABI.
719class CGObjCGNUstep : public CGObjCGNU {
720 /// The slot lookup function. Returns a pointer to a cacheable structure
721 /// that contains (among other things) the IMP.
722 LazyRuntimeFunction SlotLookupFn;
723 /// The GNUstep ABI superclass message lookup function. Takes a pointer to
724 /// a structure describing the receiver and the class, and a selector as
725 /// arguments. Returns the slot for the corresponding method. Superclass
726 /// message lookup rarely changes, so this is a good caching opportunity.
727 LazyRuntimeFunction SlotLookupSuperFn;
728 /// Specialised function for setting atomic retain properties
729 LazyRuntimeFunction SetPropertyAtomic;
730 /// Specialised function for setting atomic copy properties
731 LazyRuntimeFunction SetPropertyAtomicCopy;
732 /// Specialised function for setting nonatomic retain properties
733 LazyRuntimeFunction SetPropertyNonAtomic;
734 /// Specialised function for setting nonatomic copy properties
735 LazyRuntimeFunction SetPropertyNonAtomicCopy;
736 /// Function to perform atomic copies of C++ objects with nontrivial copy
737 /// constructors from Objective-C ivars.
738 LazyRuntimeFunction CxxAtomicObjectGetFn;
739 /// Function to perform atomic copies of C++ objects with nontrivial copy
740 /// constructors to Objective-C ivars.
741 LazyRuntimeFunction CxxAtomicObjectSetFn;
742 /// Type of a slot structure pointer. This is returned by the various
743 /// lookup functions.
744 llvm::Type *SlotTy;
745 /// Type of a slot structure.
746 llvm::Type *SlotStructTy;
747
748 public:
749 llvm::Constant *GetEHType(QualType T) override;
750
751 protected:
752 llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver,
753 llvm::Value *cmd, llvm::MDNode *node,
754 MessageSendInfo &MSI) override {
755 CGBuilderTy &Builder = CGF.Builder;
756 llvm::FunctionCallee LookupFn = SlotLookupFn;
757
758 // Store the receiver on the stack so that we can reload it later
759 Address ReceiverPtr =
760 CGF.CreateTempAlloca(Receiver->getType(), CGF.getPointerAlign());
761 Builder.CreateStore(Receiver, ReceiverPtr);
762
763 llvm::Value *self;
764
765 if (isa<ObjCMethodDecl>(CGF.CurCodeDecl)) {
766 self = CGF.LoadObjCSelf();
767 } else {
768 self = llvm::ConstantPointerNull::get(IdTy);
769 }
770
771 // The lookup function is guaranteed not to capture the receiver pointer.
772 if (auto *LookupFn2 = dyn_cast<llvm::Function>(LookupFn.getCallee()))
773 LookupFn2->addParamAttr(0, llvm::Attribute::NoCapture);
774
775 llvm::Value *args[] = {
776 EnforceType(Builder, ReceiverPtr.getPointer(), PtrToIdTy),
777 EnforceType(Builder, cmd, SelectorTy),
778 EnforceType(Builder, self, IdTy) };
779 llvm::CallBase *slot = CGF.EmitRuntimeCallOrInvoke(LookupFn, args);
780 slot->setOnlyReadsMemory();
781 slot->setMetadata(msgSendMDKind, node);
782
783 // Load the imp from the slot
784 llvm::Value *imp = Builder.CreateAlignedLoad(
785 IMPTy, Builder.CreateStructGEP(SlotStructTy, slot, 4),
786 CGF.getPointerAlign());
787
788 // The lookup function may have changed the receiver, so make sure we use
789 // the new one.
790 Receiver = Builder.CreateLoad(ReceiverPtr, true);
791 return imp;
792 }
793
794 llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, Address ObjCSuper,
795 llvm::Value *cmd,
796 MessageSendInfo &MSI) override {
797 CGBuilderTy &Builder = CGF.Builder;
798 llvm::Value *lookupArgs[] = {ObjCSuper.getPointer(), cmd};
799
800 llvm::CallInst *slot =
801 CGF.EmitNounwindRuntimeCall(SlotLookupSuperFn, lookupArgs);
802 slot->setOnlyReadsMemory();
803
804 return Builder.CreateAlignedLoad(
805 IMPTy, Builder.CreateStructGEP(SlotStructTy, slot, 4),
806 CGF.getPointerAlign());
807 }
808
809 public:
810 CGObjCGNUstep(CodeGenModule &Mod) : CGObjCGNUstep(Mod, 9, 3, 1) {}
811 CGObjCGNUstep(CodeGenModule &Mod, unsigned ABI, unsigned ProtocolABI,
812 unsigned ClassABI) :
813 CGObjCGNU(Mod, ABI, ProtocolABI, ClassABI) {
814 const ObjCRuntime &R = CGM.getLangOpts().ObjCRuntime;
815
816 SlotStructTy = llvm::StructType::get(PtrTy, PtrTy, PtrTy, IntTy, IMPTy);
817 SlotTy = llvm::PointerType::getUnqual(SlotStructTy);
818 // Slot_t objc_msg_lookup_sender(id *receiver, SEL selector, id sender);
819 SlotLookupFn.init(&CGM, "objc_msg_lookup_sender", SlotTy, PtrToIdTy,
820 SelectorTy, IdTy);
821 // Slot_t objc_slot_lookup_super(struct objc_super*, SEL);
822 SlotLookupSuperFn.init(&CGM, "objc_slot_lookup_super", SlotTy,
823 PtrToObjCSuperTy, SelectorTy);
824 // If we're in ObjC++ mode, then we want to make
825 if (usesSEHExceptions) {
826 llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
827 // void objc_exception_rethrow(void)
828 ExceptionReThrowFn.init(&CGM, "objc_exception_rethrow", VoidTy);
829 } else if (CGM.getLangOpts().CPlusPlus) {
830 llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
831 // void *__cxa_begin_catch(void *e)
832 EnterCatchFn.init(&CGM, "__cxa_begin_catch", PtrTy, PtrTy);
833 // void __cxa_end_catch(void)
834 ExitCatchFn.init(&CGM, "__cxa_end_catch", VoidTy);
835 // void _Unwind_Resume_or_Rethrow(void*)
836 ExceptionReThrowFn.init(&CGM, "_Unwind_Resume_or_Rethrow", VoidTy,
837 PtrTy);
838 } else if (R.getVersion() >= VersionTuple(1, 7)) {
839 llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
840 // id objc_begin_catch(void *e)
841 EnterCatchFn.init(&CGM, "objc_begin_catch", IdTy, PtrTy);
842 // void objc_end_catch(void)
843 ExitCatchFn.init(&CGM, "objc_end_catch", VoidTy);
844 // void _Unwind_Resume_or_Rethrow(void*)
845 ExceptionReThrowFn.init(&CGM, "objc_exception_rethrow", VoidTy, PtrTy);
846 }
847 llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
848 SetPropertyAtomic.init(&CGM, "objc_setProperty_atomic", VoidTy, IdTy,
849 SelectorTy, IdTy, PtrDiffTy);
850 SetPropertyAtomicCopy.init(&CGM, "objc_setProperty_atomic_copy", VoidTy,
851 IdTy, SelectorTy, IdTy, PtrDiffTy);
852 SetPropertyNonAtomic.init(&CGM, "objc_setProperty_nonatomic", VoidTy,
853 IdTy, SelectorTy, IdTy, PtrDiffTy);
854 SetPropertyNonAtomicCopy.init(&CGM, "objc_setProperty_nonatomic_copy",
855 VoidTy, IdTy, SelectorTy, IdTy, PtrDiffTy);
856 // void objc_setCppObjectAtomic(void *dest, const void *src, void
857 // *helper);
858 CxxAtomicObjectSetFn.init(&CGM, "objc_setCppObjectAtomic", VoidTy, PtrTy,
859 PtrTy, PtrTy);
860 // void objc_getCppObjectAtomic(void *dest, const void *src, void
861 // *helper);
862 CxxAtomicObjectGetFn.init(&CGM, "objc_getCppObjectAtomic", VoidTy, PtrTy,
863 PtrTy, PtrTy);
864 }
865
866 llvm::FunctionCallee GetCppAtomicObjectGetFunction() override {
867 // The optimised functions were added in version 1.7 of the GNUstep
868 // runtime.
869 assert (CGM.getLangOpts().ObjCRuntime.getVersion() >=(static_cast<void> (0))
870 VersionTuple(1, 7))(static_cast<void> (0));
871 return CxxAtomicObjectGetFn;
872 }
873
874 llvm::FunctionCallee GetCppAtomicObjectSetFunction() override {
875 // The optimised functions were added in version 1.7 of the GNUstep
876 // runtime.
877 assert (CGM.getLangOpts().ObjCRuntime.getVersion() >=(static_cast<void> (0))
878 VersionTuple(1, 7))(static_cast<void> (0));
879 return CxxAtomicObjectSetFn;
880 }
881
882 llvm::FunctionCallee GetOptimizedPropertySetFunction(bool atomic,
883 bool copy) override {
884 // The optimised property functions omit the GC check, and so are not
885 // safe to use in GC mode. The standard functions are fast in GC mode,
886 // so there is less advantage in using them.
887 assert ((CGM.getLangOpts().getGC() == LangOptions::NonGC))(static_cast<void> (0));
888 // The optimised functions were added in version 1.7 of the GNUstep
889 // runtime.
890 assert (CGM.getLangOpts().ObjCRuntime.getVersion() >=(static_cast<void> (0))
891 VersionTuple(1, 7))(static_cast<void> (0));
892
893 if (atomic) {
894 if (copy) return SetPropertyAtomicCopy;
895 return SetPropertyAtomic;
896 }
897
898 return copy ? SetPropertyNonAtomicCopy : SetPropertyNonAtomic;
899 }
900};
901
902/// GNUstep Objective-C ABI version 2 implementation.
903/// This is the ABI that provides a clean break with the legacy GCC ABI and
904/// cleans up a number of things that were added to work around 1980s linkers.
905class CGObjCGNUstep2 : public CGObjCGNUstep {
906 enum SectionKind
907 {
908 SelectorSection = 0,
909 ClassSection,
910 ClassReferenceSection,
911 CategorySection,
912 ProtocolSection,
913 ProtocolReferenceSection,
914 ClassAliasSection,
915 ConstantStringSection
916 };
917 static const char *const SectionsBaseNames[8];
918 static const char *const PECOFFSectionsBaseNames[8];
919 template<SectionKind K>
920 std::string sectionName() {
921 if (CGM.getTriple().isOSBinFormatCOFF()) {
922 std::string name(PECOFFSectionsBaseNames[K]);
923 name += "$m";
924 return name;
925 }
926 return SectionsBaseNames[K];
927 }
928 /// The GCC ABI superclass message lookup function. Takes a pointer to a
929 /// structure describing the receiver and the class, and a selector as
930 /// arguments. Returns the IMP for the corresponding method.
931 LazyRuntimeFunction MsgLookupSuperFn;
932 /// A flag indicating if we've emitted at least one protocol.
933 /// If we haven't, then we need to emit an empty protocol, to ensure that the
934 /// __start__objc_protocols and __stop__objc_protocols sections exist.
935 bool EmittedProtocol = false;
936 /// A flag indicating if we've emitted at least one protocol reference.
937 /// If we haven't, then we need to emit an empty protocol, to ensure that the
938 /// __start__objc_protocol_refs and __stop__objc_protocol_refs sections
939 /// exist.
940 bool EmittedProtocolRef = false;
941 /// A flag indicating if we've emitted at least one class.
942 /// If we haven't, then we need to emit an empty protocol, to ensure that the
943 /// __start__objc_classes and __stop__objc_classes sections / exist.
944 bool EmittedClass = false;
945 /// Generate the name of a symbol for a reference to a class. Accesses to
946 /// classes should be indirected via this.
947
948 typedef std::pair<std::string, std::pair<llvm::GlobalVariable*, int>>
949 EarlyInitPair;
950 std::vector<EarlyInitPair> EarlyInitList;
951
952 std::string SymbolForClassRef(StringRef Name, bool isWeak) {
953 if (isWeak)
954 return (ManglePublicSymbol("OBJC_WEAK_REF_CLASS_") + Name).str();
955 else
956 return (ManglePublicSymbol("OBJC_REF_CLASS_") + Name).str();
957 }
958 /// Generate the name of a class symbol.
959 std::string SymbolForClass(StringRef Name) {
960 return (ManglePublicSymbol("OBJC_CLASS_") + Name).str();
961 }
962 void CallRuntimeFunction(CGBuilderTy &B, StringRef FunctionName,
963 ArrayRef<llvm::Value*> Args) {
964 SmallVector<llvm::Type *,8> Types;
965 for (auto *Arg : Args)
966 Types.push_back(Arg->getType());
967 llvm::FunctionType *FT = llvm::FunctionType::get(B.getVoidTy(), Types,
968 false);
969 llvm::FunctionCallee Fn = CGM.CreateRuntimeFunction(FT, FunctionName);
970 B.CreateCall(Fn, Args);
971 }
972
973 ConstantAddress GenerateConstantString(const StringLiteral *SL) override {
974
975 auto Str = SL->getString();
976 CharUnits Align = CGM.getPointerAlign();
977
978 // Look for an existing one
979 llvm::StringMap<llvm::Constant*>::iterator old = ObjCStrings.find(Str);
980 if (old != ObjCStrings.end())
981 return ConstantAddress(old->getValue(), Align);
982
983 bool isNonASCII = SL->containsNonAscii();
984
985 auto LiteralLength = SL->getLength();
986
987 if ((CGM.getTarget().getPointerWidth(0) == 64) &&
988 (LiteralLength < 9) && !isNonASCII) {
989 // Tiny strings are only used on 64-bit platforms. They store 8 7-bit
990 // ASCII characters in the high 56 bits, followed by a 4-bit length and a
991 // 3-bit tag (which is always 4).
992 uint64_t str = 0;
993 // Fill in the characters
994 for (unsigned i=0 ; i<LiteralLength ; i++)
995 str |= ((uint64_t)SL->getCodeUnit(i)) << ((64 - 4 - 3) - (i*7));
996 // Fill in the length
997 str |= LiteralLength << 3;
998 // Set the tag
999 str |= 4;
1000 auto *ObjCStr = llvm::ConstantExpr::getIntToPtr(
1001 llvm::ConstantInt::get(Int64Ty, str), IdTy);
1002 ObjCStrings[Str] = ObjCStr;
1003 return ConstantAddress(ObjCStr, Align);
1004 }
1005
1006 StringRef StringClass = CGM.getLangOpts().ObjCConstantStringClass;
1007
1008 if (StringClass.empty()) StringClass = "NSConstantString";
1009
1010 std::string Sym = SymbolForClass(StringClass);
1011
1012 llvm::Constant *isa = TheModule.getNamedGlobal(Sym);
1013
1014 if (!isa) {
1015 isa = new llvm::GlobalVariable(TheModule, IdTy, /* isConstant */false,
1016 llvm::GlobalValue::ExternalLinkage, nullptr, Sym);
1017 if (CGM.getTriple().isOSBinFormatCOFF()) {
1018 cast<llvm::GlobalValue>(isa)->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
1019 }
1020 } else if (isa->getType() != PtrToIdTy)
1021 isa = llvm::ConstantExpr::getBitCast(isa, PtrToIdTy);
1022
1023 // struct
1024 // {
1025 // Class isa;
1026 // uint32_t flags;
1027 // uint32_t length; // Number of codepoints
1028 // uint32_t size; // Number of bytes
1029 // uint32_t hash;
1030 // const char *data;
1031 // };
1032
1033 ConstantInitBuilder Builder(CGM);
1034 auto Fields = Builder.beginStruct();
1035 if (!CGM.getTriple().isOSBinFormatCOFF()) {
1036 Fields.add(isa);
1037 } else {
1038 Fields.addNullPointer(PtrTy);
1039 }
1040 // For now, all non-ASCII strings are represented as UTF-16. As such, the
1041 // number of bytes is simply double the number of UTF-16 codepoints. In
1042 // ASCII strings, the number of bytes is equal to the number of non-ASCII
1043 // codepoints.
1044 if (isNonASCII) {
1045 unsigned NumU8CodeUnits = Str.size();
1046 // A UTF-16 representation of a unicode string contains at most the same
1047 // number of code units as a UTF-8 representation. Allocate that much
1048 // space, plus one for the final null character.
1049 SmallVector<llvm::UTF16, 128> ToBuf(NumU8CodeUnits + 1);
1050 const llvm::UTF8 *FromPtr = (const llvm::UTF8 *)Str.data();
1051 llvm::UTF16 *ToPtr = &ToBuf[0];
1052 (void)llvm::ConvertUTF8toUTF16(&FromPtr, FromPtr + NumU8CodeUnits,
1053 &ToPtr, ToPtr + NumU8CodeUnits, llvm::strictConversion);
1054 uint32_t StringLength = ToPtr - &ToBuf[0];
1055 // Add null terminator
1056 *ToPtr = 0;
1057 // Flags: 2 indicates UTF-16 encoding
1058 Fields.addInt(Int32Ty, 2);
1059 // Number of UTF-16 codepoints
1060 Fields.addInt(Int32Ty, StringLength);
1061 // Number of bytes
1062 Fields.addInt(Int32Ty, StringLength * 2);
1063 // Hash. Not currently initialised by the compiler.
1064 Fields.addInt(Int32Ty, 0);
1065 // pointer to the data string.
1066 auto Arr = llvm::makeArrayRef(&ToBuf[0], ToPtr+1);
1067 auto *C = llvm::ConstantDataArray::get(VMContext, Arr);
1068 auto *Buffer = new llvm::GlobalVariable(TheModule, C->getType(),
1069 /*isConstant=*/true, llvm::GlobalValue::PrivateLinkage, C, ".str");
1070 Buffer->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
1071 Fields.add(Buffer);
1072 } else {
1073 // Flags: 0 indicates ASCII encoding
1074 Fields.addInt(Int32Ty, 0);
1075 // Number of UTF-16 codepoints, each ASCII byte is a UTF-16 codepoint
1076 Fields.addInt(Int32Ty, Str.size());
1077 // Number of bytes
1078 Fields.addInt(Int32Ty, Str.size());
1079 // Hash. Not currently initialised by the compiler.
1080 Fields.addInt(Int32Ty, 0);
1081 // Data pointer
1082 Fields.add(MakeConstantString(Str));
1083 }
1084 std::string StringName;
1085 bool isNamed = !isNonASCII;
1086 if (isNamed) {
1087 StringName = ".objc_str_";
1088 for (int i=0,e=Str.size() ; i<e ; ++i) {
1089 unsigned char c = Str[i];
1090 if (isalnum(c))
1091 StringName += c;
1092 else if (c == ' ')
1093 StringName += '_';
1094 else {
1095 isNamed = false;
1096 break;
1097 }
1098 }
1099 }
1100 llvm::GlobalVariable *ObjCStrGV =
1101 Fields.finishAndCreateGlobal(
1102 isNamed ? StringRef(StringName) : ".objc_string",
1103 Align, false, isNamed ? llvm::GlobalValue::LinkOnceODRLinkage
1104 : llvm::GlobalValue::PrivateLinkage);
1105 ObjCStrGV->setSection(sectionName<ConstantStringSection>());
1106 if (isNamed) {
1107 ObjCStrGV->setComdat(TheModule.getOrInsertComdat(StringName));
1108 ObjCStrGV->setVisibility(llvm::GlobalValue::HiddenVisibility);
1109 }
1110 if (CGM.getTriple().isOSBinFormatCOFF()) {
1111 std::pair<llvm::GlobalVariable*, int> v{ObjCStrGV, 0};
1112 EarlyInitList.emplace_back(Sym, v);
1113 }
1114 llvm::Constant *ObjCStr = llvm::ConstantExpr::getBitCast(ObjCStrGV, IdTy);
1115 ObjCStrings[Str] = ObjCStr;
1116 ConstantStrings.push_back(ObjCStr);
1117 return ConstantAddress(ObjCStr, Align);
1118 }
1119
1120 void PushProperty(ConstantArrayBuilder &PropertiesArray,
1121 const ObjCPropertyDecl *property,
1122 const Decl *OCD,
1123 bool isSynthesized=true, bool
1124 isDynamic=true) override {
1125 // struct objc_property
1126 // {
1127 // const char *name;
1128 // const char *attributes;
1129 // const char *type;
1130 // SEL getter;
1131 // SEL setter;
1132 // };
1133 auto Fields = PropertiesArray.beginStruct(PropertyMetadataTy);
1134 ASTContext &Context = CGM.getContext();
1135 Fields.add(MakeConstantString(property->getNameAsString()));
1136 std::string TypeStr =
1137 CGM.getContext().getObjCEncodingForPropertyDecl(property, OCD);
1138 Fields.add(MakeConstantString(TypeStr));
1139 std::string typeStr;
1140 Context.getObjCEncodingForType(property->getType(), typeStr);
1141 Fields.add(MakeConstantString(typeStr));
1142 auto addPropertyMethod = [&](const ObjCMethodDecl *accessor) {
1143 if (accessor) {
1144 std::string TypeStr = Context.getObjCEncodingForMethodDecl(accessor);
1145 Fields.add(GetConstantSelector(accessor->getSelector(), TypeStr));
1146 } else {
1147 Fields.add(NULLPtr);
1148 }
1149 };
1150 addPropertyMethod(property->getGetterMethodDecl());
1151 addPropertyMethod(property->getSetterMethodDecl());
1152 Fields.finishAndAddTo(PropertiesArray);
1153 }
1154
1155 llvm::Constant *
1156 GenerateProtocolMethodList(ArrayRef<const ObjCMethodDecl*> Methods) override {
1157 // struct objc_protocol_method_description
1158 // {
1159 // SEL selector;
1160 // const char *types;
1161 // };
1162 llvm::StructType *ObjCMethodDescTy =
1163 llvm::StructType::get(CGM.getLLVMContext(),
1164 { PtrToInt8Ty, PtrToInt8Ty });
1165 ASTContext &Context = CGM.getContext();
1166 ConstantInitBuilder Builder(CGM);
1167 // struct objc_protocol_method_description_list
1168 // {
1169 // int count;
1170 // int size;
1171 // struct objc_protocol_method_description methods[];
1172 // };
1173 auto MethodList = Builder.beginStruct();
1174 // int count;
1175 MethodList.addInt(IntTy, Methods.size());
1176 // int size; // sizeof(struct objc_method_description)
1177 llvm::DataLayout td(&TheModule);
1178 MethodList.addInt(IntTy, td.getTypeSizeInBits(ObjCMethodDescTy) /
1179 CGM.getContext().getCharWidth());
1180 // struct objc_method_description[]
1181 auto MethodArray = MethodList.beginArray(ObjCMethodDescTy);
1182 for (auto *M : Methods) {
1183 auto Method = MethodArray.beginStruct(ObjCMethodDescTy);
1184 Method.add(CGObjCGNU::GetConstantSelector(M));
1185 Method.add(GetTypeString(Context.getObjCEncodingForMethodDecl(M, true)));
1186 Method.finishAndAddTo(MethodArray);
1187 }
1188 MethodArray.finishAndAddTo(MethodList);
1189 return MethodList.finishAndCreateGlobal(".objc_protocol_method_list",
1190 CGM.getPointerAlign());
1191 }
1192 llvm::Constant *GenerateCategoryProtocolList(const ObjCCategoryDecl *OCD)
1193 override {
1194 const auto &ReferencedProtocols = OCD->getReferencedProtocols();
1195 auto RuntimeProtocols = GetRuntimeProtocolList(ReferencedProtocols.begin(),
1196 ReferencedProtocols.end());
1197 SmallVector<llvm::Constant *, 16> Protocols;
1198 for (const auto *PI : RuntimeProtocols)
1199 Protocols.push_back(
1200 llvm::ConstantExpr::getBitCast(GenerateProtocolRef(PI),
1201 ProtocolPtrTy));
1202 return GenerateProtocolList(Protocols);
1203 }
1204
1205 llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, Address ObjCSuper,
1206 llvm::Value *cmd, MessageSendInfo &MSI) override {
1207 // Don't access the slot unless we're trying to cache the result.
1208 CGBuilderTy &Builder = CGF.Builder;
1209 llvm::Value *lookupArgs[] = {CGObjCGNU::EnforceType(Builder, ObjCSuper,
1210 PtrToObjCSuperTy).getPointer(), cmd};
1211 return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFn, lookupArgs);
1212 }
1213
1214 llvm::GlobalVariable *GetClassVar(StringRef Name, bool isWeak=false) {
1215 std::string SymbolName = SymbolForClassRef(Name, isWeak);
1216 auto *ClassSymbol = TheModule.getNamedGlobal(SymbolName);
1217 if (ClassSymbol)
1218 return ClassSymbol;
1219 ClassSymbol = new llvm::GlobalVariable(TheModule,
1220 IdTy, false, llvm::GlobalValue::ExternalLinkage,
1221 nullptr, SymbolName);
1222 // If this is a weak symbol, then we are creating a valid definition for
1223 // the symbol, pointing to a weak definition of the real class pointer. If
1224 // this is not a weak reference, then we are expecting another compilation
1225 // unit to provide the real indirection symbol.
1226 if (isWeak)
1227 ClassSymbol->setInitializer(new llvm::GlobalVariable(TheModule,
1228 Int8Ty, false, llvm::GlobalValue::ExternalWeakLinkage,
1229 nullptr, SymbolForClass(Name)));
1230 else {
1231 if (CGM.getTriple().isOSBinFormatCOFF()) {
1232 IdentifierInfo &II = CGM.getContext().Idents.get(Name);
1233 TranslationUnitDecl *TUDecl = CGM.getContext().getTranslationUnitDecl();
1234 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl);
1235
1236 const ObjCInterfaceDecl *OID = nullptr;
1237 for (const auto *Result : DC->lookup(&II))
1238 if ((OID = dyn_cast<ObjCInterfaceDecl>(Result)))
1239 break;
1240
1241 // The first Interface we find may be a @class,
1242 // which should only be treated as the source of
1243 // truth in the absence of a true declaration.
1244 assert(OID && "Failed to find ObjCInterfaceDecl")(static_cast<void> (0));
1245 const ObjCInterfaceDecl *OIDDef = OID->getDefinition();
1246 if (OIDDef != nullptr)
1247 OID = OIDDef;
1248
1249 auto Storage = llvm::GlobalValue::DefaultStorageClass;
1250 if (OID->hasAttr<DLLImportAttr>())
1251 Storage = llvm::GlobalValue::DLLImportStorageClass;
1252 else if (OID->hasAttr<DLLExportAttr>())
1253 Storage = llvm::GlobalValue::DLLExportStorageClass;
1254
1255 cast<llvm::GlobalValue>(ClassSymbol)->setDLLStorageClass(Storage);
1256 }
1257 }
1258 assert(ClassSymbol->getName() == SymbolName)(static_cast<void> (0));
1259 return ClassSymbol;
1260 }
1261 llvm::Value *GetClassNamed(CodeGenFunction &CGF,
1262 const std::string &Name,
1263 bool isWeak) override {
1264 return CGF.Builder.CreateLoad(Address(GetClassVar(Name, isWeak),
1265 CGM.getPointerAlign()));
1266 }
1267 int32_t FlagsForOwnership(Qualifiers::ObjCLifetime Ownership) {
1268 // typedef enum {
1269 // ownership_invalid = 0,
1270 // ownership_strong = 1,
1271 // ownership_weak = 2,
1272 // ownership_unsafe = 3
1273 // } ivar_ownership;
1274 int Flag;
1275 switch (Ownership) {
1276 case Qualifiers::OCL_Strong:
1277 Flag = 1;
1278 break;
1279 case Qualifiers::OCL_Weak:
1280 Flag = 2;
1281 break;
1282 case Qualifiers::OCL_ExplicitNone:
1283 Flag = 3;
1284 break;
1285 case Qualifiers::OCL_None:
1286 case Qualifiers::OCL_Autoreleasing:
1287 assert(Ownership != Qualifiers::OCL_Autoreleasing)(static_cast<void> (0));
1288 Flag = 0;
1289 }
1290 return Flag;
1291 }
1292 llvm::Constant *GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames,
1293 ArrayRef<llvm::Constant *> IvarTypes,
1294 ArrayRef<llvm::Constant *> IvarOffsets,
1295 ArrayRef<llvm::Constant *> IvarAlign,
1296 ArrayRef<Qualifiers::ObjCLifetime> IvarOwnership) override {
1297 llvm_unreachable("Method should not be called!")__builtin_unreachable();
1298 }
1299
1300 llvm::Constant *GenerateEmptyProtocol(StringRef ProtocolName) override {
1301 std::string Name = SymbolForProtocol(ProtocolName);
1302 auto *GV = TheModule.getGlobalVariable(Name);
1303 if (!GV) {
1304 // Emit a placeholder symbol.
1305 GV = new llvm::GlobalVariable(TheModule, ProtocolTy, false,
1306 llvm::GlobalValue::ExternalLinkage, nullptr, Name);
1307 GV->setAlignment(CGM.getPointerAlign().getAsAlign());
1308 }
1309 return llvm::ConstantExpr::getBitCast(GV, ProtocolPtrTy);
1310 }
1311
1312 /// Existing protocol references.
1313 llvm::StringMap<llvm::Constant*> ExistingProtocolRefs;
1314
1315 llvm::Value *GenerateProtocolRef(CodeGenFunction &CGF,
1316 const ObjCProtocolDecl *PD) override {
1317 auto Name = PD->getNameAsString();
1318 auto *&Ref = ExistingProtocolRefs[Name];
1319 if (!Ref) {
1320 auto *&Protocol = ExistingProtocols[Name];
1321 if (!Protocol)
1322 Protocol = GenerateProtocolRef(PD);
1323 std::string RefName = SymbolForProtocolRef(Name);
1324 assert(!TheModule.getGlobalVariable(RefName))(static_cast<void> (0));
1325 // Emit a reference symbol.
1326 auto GV = new llvm::GlobalVariable(TheModule, ProtocolPtrTy,
1327 false, llvm::GlobalValue::LinkOnceODRLinkage,
1328 llvm::ConstantExpr::getBitCast(Protocol, ProtocolPtrTy), RefName);
1329 GV->setComdat(TheModule.getOrInsertComdat(RefName));
1330 GV->setSection(sectionName<ProtocolReferenceSection>());
1331 GV->setAlignment(CGM.getPointerAlign().getAsAlign());
1332 Ref = GV;
1333 }
1334 EmittedProtocolRef = true;
1335 return CGF.Builder.CreateAlignedLoad(ProtocolPtrTy, Ref,
1336 CGM.getPointerAlign());
1337 }
1338
1339 llvm::Constant *GenerateProtocolList(ArrayRef<llvm::Constant*> Protocols) {
1340 llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(ProtocolPtrTy,
1341 Protocols.size());
1342 llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy,
1343 Protocols);
1344 ConstantInitBuilder builder(CGM);
1345 auto ProtocolBuilder = builder.beginStruct();
1346 ProtocolBuilder.addNullPointer(PtrTy);
1347 ProtocolBuilder.addInt(SizeTy, Protocols.size());
1348 ProtocolBuilder.add(ProtocolArray);
1349 return ProtocolBuilder.finishAndCreateGlobal(".objc_protocol_list",
1350 CGM.getPointerAlign(), false, llvm::GlobalValue::InternalLinkage);
1351 }
1352
1353 void GenerateProtocol(const ObjCProtocolDecl *PD) override {
1354 // Do nothing - we only emit referenced protocols.
1355 }
1356 llvm::Constant *GenerateProtocolRef(const ObjCProtocolDecl *PD) override {
1357 std::string ProtocolName = PD->getNameAsString();
1358 auto *&Protocol = ExistingProtocols[ProtocolName];
1359 if (Protocol)
1360 return Protocol;
1361
1362 EmittedProtocol = true;
1363
1364 auto SymName = SymbolForProtocol(ProtocolName);
1365 auto *OldGV = TheModule.getGlobalVariable(SymName);
1366
1367 // Use the protocol definition, if there is one.
1368 if (const ObjCProtocolDecl *Def = PD->getDefinition())
1369 PD = Def;
1370 else {
1371 // If there is no definition, then create an external linkage symbol and
1372 // hope that someone else fills it in for us (and fail to link if they
1373 // don't).
1374 assert(!OldGV)(static_cast<void> (0));
1375 Protocol = new llvm::GlobalVariable(TheModule, ProtocolTy,
1376 /*isConstant*/false,
1377 llvm::GlobalValue::ExternalLinkage, nullptr, SymName);
1378 return Protocol;
1379 }
1380
1381 SmallVector<llvm::Constant*, 16> Protocols;
1382 auto RuntimeProtocols =
1383 GetRuntimeProtocolList(PD->protocol_begin(), PD->protocol_end());
1384 for (const auto *PI : RuntimeProtocols)
1385 Protocols.push_back(
1386 llvm::ConstantExpr::getBitCast(GenerateProtocolRef(PI),
1387 ProtocolPtrTy));
1388 llvm::Constant *ProtocolList = GenerateProtocolList(Protocols);
1389
1390 // Collect information about methods
1391 llvm::Constant *InstanceMethodList, *OptionalInstanceMethodList;
1392 llvm::Constant *ClassMethodList, *OptionalClassMethodList;
1393 EmitProtocolMethodList(PD->instance_methods(), InstanceMethodList,
1394 OptionalInstanceMethodList);
1395 EmitProtocolMethodList(PD->class_methods(), ClassMethodList,
1396 OptionalClassMethodList);
1397
1398 // The isa pointer must be set to a magic number so the runtime knows it's
1399 // the correct layout.
1400 ConstantInitBuilder builder(CGM);
1401 auto ProtocolBuilder = builder.beginStruct();
1402 ProtocolBuilder.add(llvm::ConstantExpr::getIntToPtr(
1403 llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy));
1404 ProtocolBuilder.add(MakeConstantString(ProtocolName));
1405 ProtocolBuilder.add(ProtocolList);
1406 ProtocolBuilder.add(InstanceMethodList);
1407 ProtocolBuilder.add(ClassMethodList);
1408 ProtocolBuilder.add(OptionalInstanceMethodList);
1409 ProtocolBuilder.add(OptionalClassMethodList);
1410 // Required instance properties
1411 ProtocolBuilder.add(GeneratePropertyList(nullptr, PD, false, false));
1412 // Optional instance properties
1413 ProtocolBuilder.add(GeneratePropertyList(nullptr, PD, false, true));
1414 // Required class properties
1415 ProtocolBuilder.add(GeneratePropertyList(nullptr, PD, true, false));
1416 // Optional class properties
1417 ProtocolBuilder.add(GeneratePropertyList(nullptr, PD, true, true));
1418
1419 auto *GV = ProtocolBuilder.finishAndCreateGlobal(SymName,
1420 CGM.getPointerAlign(), false, llvm::GlobalValue::ExternalLinkage);
1421 GV->setSection(sectionName<ProtocolSection>());
1422 GV->setComdat(TheModule.getOrInsertComdat(SymName));
1423 if (OldGV) {
1424 OldGV->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GV,
1425 OldGV->getType()));
1426 OldGV->removeFromParent();
1427 GV->setName(SymName);
1428 }
1429 Protocol = GV;
1430 return GV;
1431 }
1432 llvm::Constant *EnforceType(llvm::Constant *Val, llvm::Type *Ty) {
1433 if (Val->getType() == Ty)
1434 return Val;
1435 return llvm::ConstantExpr::getBitCast(Val, Ty);
1436 }
1437 llvm::Value *GetTypedSelector(CodeGenFunction &CGF, Selector Sel,
1438 const std::string &TypeEncoding) override {
1439 return GetConstantSelector(Sel, TypeEncoding);
1440 }
1441 llvm::Constant *GetTypeString(llvm::StringRef TypeEncoding) {
1442 if (TypeEncoding.empty())
1443 return NULLPtr;
1444 std::string MangledTypes = std::string(TypeEncoding);
1445 std::replace(MangledTypes.begin(), MangledTypes.end(),
1446 '@', '\1');
1447 std::string TypesVarName = ".objc_sel_types_" + MangledTypes;
1448 auto *TypesGlobal = TheModule.getGlobalVariable(TypesVarName);
1449 if (!TypesGlobal) {
1450 llvm::Constant *Init = llvm::ConstantDataArray::getString(VMContext,
1451 TypeEncoding);
1452 auto *GV = new llvm::GlobalVariable(TheModule, Init->getType(),
1453 true, llvm::GlobalValue::LinkOnceODRLinkage, Init, TypesVarName);
1454 GV->setComdat(TheModule.getOrInsertComdat(TypesVarName));
1455 GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
1456 TypesGlobal = GV;
1457 }
1458 return llvm::ConstantExpr::getGetElementPtr(TypesGlobal->getValueType(),
1459 TypesGlobal, Zeros);
1460 }
1461 llvm::Constant *GetConstantSelector(Selector Sel,
1462 const std::string &TypeEncoding) override {
1463 // @ is used as a special character in symbol names (used for symbol
1464 // versioning), so mangle the name to not include it. Replace it with a
1465 // character that is not a valid type encoding character (and, being
1466 // non-printable, never will be!)
1467 std::string MangledTypes = TypeEncoding;
1468 std::replace(MangledTypes.begin(), MangledTypes.end(),
1469 '@', '\1');
1470 auto SelVarName = (StringRef(".objc_selector_") + Sel.getAsString() + "_" +
1471 MangledTypes).str();
1472 if (auto *GV = TheModule.getNamedGlobal(SelVarName))
1473 return EnforceType(GV, SelectorTy);
1474 ConstantInitBuilder builder(CGM);
1475 auto SelBuilder = builder.beginStruct();
1476 SelBuilder.add(ExportUniqueString(Sel.getAsString(), ".objc_sel_name_",
1477 true));
1478 SelBuilder.add(GetTypeString(TypeEncoding));
1479 auto *GV = SelBuilder.finishAndCreateGlobal(SelVarName,
1480 CGM.getPointerAlign(), false, llvm::GlobalValue::LinkOnceODRLinkage);
1481 GV->setComdat(TheModule.getOrInsertComdat(SelVarName));
1482 GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
1483 GV->setSection(sectionName<SelectorSection>());
1484 auto *SelVal = EnforceType(GV, SelectorTy);
1485 return SelVal;
1486 }
1487 llvm::StructType *emptyStruct = nullptr;
1488
1489 /// Return pointers to the start and end of a section. On ELF platforms, we
1490 /// use the __start_ and __stop_ symbols that GNU-compatible linkers will set
1491 /// to the start and end of section names, as long as those section names are
1492 /// valid identifiers and the symbols are referenced but not defined. On
1493 /// Windows, we use the fact that MSVC-compatible linkers will lexically sort
1494 /// by subsections and place everything that we want to reference in a middle
1495 /// subsection and then insert zero-sized symbols in subsections a and z.
1496 std::pair<llvm::Constant*,llvm::Constant*>
1497 GetSectionBounds(StringRef Section) {
1498 if (CGM.getTriple().isOSBinFormatCOFF()) {
1499 if (emptyStruct == nullptr) {
1500 emptyStruct = llvm::StructType::create(VMContext, ".objc_section_sentinel");
1501 emptyStruct->setBody({}, /*isPacked*/true);
1502 }
1503 auto ZeroInit = llvm::Constant::getNullValue(emptyStruct);
1504 auto Sym = [&](StringRef Prefix, StringRef SecSuffix) {
1505 auto *Sym = new llvm::GlobalVariable(TheModule, emptyStruct,
1506 /*isConstant*/false,
1507 llvm::GlobalValue::LinkOnceODRLinkage, ZeroInit, Prefix +
1508 Section);
1509 Sym->setVisibility(llvm::GlobalValue::HiddenVisibility);
1510 Sym->setSection((Section + SecSuffix).str());
1511 Sym->setComdat(TheModule.getOrInsertComdat((Prefix +
1512 Section).str()));
1513 Sym->setAlignment(CGM.getPointerAlign().getAsAlign());
1514 return Sym;
1515 };
1516 return { Sym("__start_", "$a"), Sym("__stop", "$z") };
1517 }
1518 auto *Start = new llvm::GlobalVariable(TheModule, PtrTy,
1519 /*isConstant*/false,
1520 llvm::GlobalValue::ExternalLinkage, nullptr, StringRef("__start_") +
1521 Section);
1522 Start->setVisibility(llvm::GlobalValue::HiddenVisibility);
1523 auto *Stop = new llvm::GlobalVariable(TheModule, PtrTy,
1524 /*isConstant*/false,
1525 llvm::GlobalValue::ExternalLinkage, nullptr, StringRef("__stop_") +
1526 Section);
1527 Stop->setVisibility(llvm::GlobalValue::HiddenVisibility);
1528 return { Start, Stop };
1529 }
1530 CatchTypeInfo getCatchAllTypeInfo() override {
1531 return CGM.getCXXABI().getCatchAllTypeInfo();
1532 }
1533 llvm::Function *ModuleInitFunction() override {
1534 llvm::Function *LoadFunction = llvm::Function::Create(
1535 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), false),
1536 llvm::GlobalValue::LinkOnceODRLinkage, ".objcv2_load_function",
1537 &TheModule);
1538 LoadFunction->setVisibility(llvm::GlobalValue::HiddenVisibility);
1539 LoadFunction->setComdat(TheModule.getOrInsertComdat(".objcv2_load_function"));
1540
1541 llvm::BasicBlock *EntryBB =
1542 llvm::BasicBlock::Create(VMContext, "entry", LoadFunction);
1543 CGBuilderTy B(CGM, VMContext);
1544 B.SetInsertPoint(EntryBB);
1545 ConstantInitBuilder builder(CGM);
1546 auto InitStructBuilder = builder.beginStruct();
1547 InitStructBuilder.addInt(Int64Ty, 0);
1548 auto &sectionVec = CGM.getTriple().isOSBinFormatCOFF() ? PECOFFSectionsBaseNames : SectionsBaseNames;
1549 for (auto *s : sectionVec) {
1550 auto bounds = GetSectionBounds(s);
1551 InitStructBuilder.add(bounds.first);
1552 InitStructBuilder.add(bounds.second);
1553 }
1554 auto *InitStruct = InitStructBuilder.finishAndCreateGlobal(".objc_init",
1555 CGM.getPointerAlign(), false, llvm::GlobalValue::LinkOnceODRLinkage);
1556 InitStruct->setVisibility(llvm::GlobalValue::HiddenVisibility);
1557 InitStruct->setComdat(TheModule.getOrInsertComdat(".objc_init"));
1558
1559 CallRuntimeFunction(B, "__objc_load", {InitStruct});;
1560 B.CreateRetVoid();
1561 // Make sure that the optimisers don't delete this function.
1562 CGM.addCompilerUsedGlobal(LoadFunction);
1563 // FIXME: Currently ELF only!
1564 // We have to do this by hand, rather than with @llvm.ctors, so that the
1565 // linker can remove the duplicate invocations.
1566 auto *InitVar = new llvm::GlobalVariable(TheModule, LoadFunction->getType(),
1567 /*isConstant*/false, llvm::GlobalValue::LinkOnceAnyLinkage,
1568 LoadFunction, ".objc_ctor");
1569 // Check that this hasn't been renamed. This shouldn't happen, because
1570 // this function should be called precisely once.
1571 assert(InitVar->getName() == ".objc_ctor")(static_cast<void> (0));
1572 // In Windows, initialisers are sorted by the suffix. XCL is for library
1573 // initialisers, which run before user initialisers. We are running
1574 // Objective-C loads at the end of library load. This means +load methods
1575 // will run before any other static constructors, but that static
1576 // constructors can see a fully initialised Objective-C state.
1577 if (CGM.getTriple().isOSBinFormatCOFF())
1578 InitVar->setSection(".CRT$XCLz");
1579 else
1580 {
1581 if (CGM.getCodeGenOpts().UseInitArray)
1582 InitVar->setSection(".init_array");
1583 else
1584 InitVar->setSection(".ctors");
1585 }
1586 InitVar->setVisibility(llvm::GlobalValue::HiddenVisibility);
1587 InitVar->setComdat(TheModule.getOrInsertComdat(".objc_ctor"));
1588 CGM.addUsedGlobal(InitVar);
1589 for (auto *C : Categories) {
1590 auto *Cat = cast<llvm::GlobalVariable>(C->stripPointerCasts());
1591 Cat->setSection(sectionName<CategorySection>());
1592 CGM.addUsedGlobal(Cat);
1593 }
1594 auto createNullGlobal = [&](StringRef Name, ArrayRef<llvm::Constant*> Init,
1595 StringRef Section) {
1596 auto nullBuilder = builder.beginStruct();
1597 for (auto *F : Init)
1598 nullBuilder.add(F);
1599 auto GV = nullBuilder.finishAndCreateGlobal(Name, CGM.getPointerAlign(),
1600 false, llvm::GlobalValue::LinkOnceODRLinkage);
1601 GV->setSection(Section);
1602 GV->setComdat(TheModule.getOrInsertComdat(Name));
1603 GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
1604 CGM.addUsedGlobal(GV);
1605 return GV;
1606 };
1607 for (auto clsAlias : ClassAliases)
1608 createNullGlobal(std::string(".objc_class_alias") +
1609 clsAlias.second, { MakeConstantString(clsAlias.second),
1610 GetClassVar(clsAlias.first) }, sectionName<ClassAliasSection>());
1611 // On ELF platforms, add a null value for each special section so that we
1612 // can always guarantee that the _start and _stop symbols will exist and be
1613 // meaningful. This is not required on COFF platforms, where our start and
1614 // stop symbols will create the section.
1615 if (!CGM.getTriple().isOSBinFormatCOFF()) {
1616 createNullGlobal(".objc_null_selector", {NULLPtr, NULLPtr},
1617 sectionName<SelectorSection>());
1618 if (Categories.empty())
1619 createNullGlobal(".objc_null_category", {NULLPtr, NULLPtr,
1620 NULLPtr, NULLPtr, NULLPtr, NULLPtr, NULLPtr},
1621 sectionName<CategorySection>());
1622 if (!EmittedClass) {
1623 createNullGlobal(".objc_null_cls_init_ref", NULLPtr,
1624 sectionName<ClassSection>());
1625 createNullGlobal(".objc_null_class_ref", { NULLPtr, NULLPtr },
1626 sectionName<ClassReferenceSection>());
1627 }
1628 if (!EmittedProtocol)
1629 createNullGlobal(".objc_null_protocol", {NULLPtr, NULLPtr, NULLPtr,
1630 NULLPtr, NULLPtr, NULLPtr, NULLPtr, NULLPtr, NULLPtr, NULLPtr,
1631 NULLPtr}, sectionName<ProtocolSection>());
1632 if (!EmittedProtocolRef)
1633 createNullGlobal(".objc_null_protocol_ref", {NULLPtr},
1634 sectionName<ProtocolReferenceSection>());
1635 if (ClassAliases.empty())
1636 createNullGlobal(".objc_null_class_alias", { NULLPtr, NULLPtr },
1637 sectionName<ClassAliasSection>());
1638 if (ConstantStrings.empty()) {
1639 auto i32Zero = llvm::ConstantInt::get(Int32Ty, 0);
1640 createNullGlobal(".objc_null_constant_string", { NULLPtr, i32Zero,
1641 i32Zero, i32Zero, i32Zero, NULLPtr },
1642 sectionName<ConstantStringSection>());
1643 }
1644 }
1645 ConstantStrings.clear();
1646 Categories.clear();
1647 Classes.clear();
1648
1649 if (EarlyInitList.size() > 0) {
1650 auto *Init = llvm::Function::Create(llvm::FunctionType::get(CGM.VoidTy,
1651 {}), llvm::GlobalValue::InternalLinkage, ".objc_early_init",
1652 &CGM.getModule());
1653 llvm::IRBuilder<> b(llvm::BasicBlock::Create(CGM.getLLVMContext(), "entry",
1654 Init));
1655 for (const auto &lateInit : EarlyInitList) {
1656 auto *global = TheModule.getGlobalVariable(lateInit.first);
1657 if (global) {
1658 llvm::GlobalVariable *GV = lateInit.second.first;
1659 b.CreateAlignedStore(
1660 global,
1661 b.CreateStructGEP(GV->getValueType(), GV, lateInit.second.second),
1662 CGM.getPointerAlign().getAsAlign());
1663 }
1664 }
1665 b.CreateRetVoid();
1666 // We can't use the normal LLVM global initialisation array, because we
1667 // need to specify that this runs early in library initialisation.
1668 auto *InitVar = new llvm::GlobalVariable(CGM.getModule(), Init->getType(),
1669 /*isConstant*/true, llvm::GlobalValue::InternalLinkage,
1670 Init, ".objc_early_init_ptr");
1671 InitVar->setSection(".CRT$XCLb");
1672 CGM.addUsedGlobal(InitVar);
1673 }
1674 return nullptr;
1675 }
1676 /// In the v2 ABI, ivar offset variables use the type encoding in their name
1677 /// to trigger linker failures if the types don't match.
1678 std::string GetIVarOffsetVariableName(const ObjCInterfaceDecl *ID,
1679 const ObjCIvarDecl *Ivar) override {
1680 std::string TypeEncoding;
1681 CGM.getContext().getObjCEncodingForType(Ivar->getType(), TypeEncoding);
1682 // Prevent the @ from being interpreted as a symbol version.
1683 std::replace(TypeEncoding.begin(), TypeEncoding.end(),
1684 '@', '\1');
1685 const std::string Name = "__objc_ivar_offset_" + ID->getNameAsString()
1686 + '.' + Ivar->getNameAsString() + '.' + TypeEncoding;
1687 return Name;
1688 }
1689 llvm::Value *EmitIvarOffset(CodeGenFunction &CGF,
1690 const ObjCInterfaceDecl *Interface,
1691 const ObjCIvarDecl *Ivar) override {
1692 const std::string Name = GetIVarOffsetVariableName(Ivar->getContainingInterface(), Ivar);
1693 llvm::GlobalVariable *IvarOffsetPointer = TheModule.getNamedGlobal(Name);
1694 if (!IvarOffsetPointer)
1695 IvarOffsetPointer = new llvm::GlobalVariable(TheModule, IntTy, false,
1696 llvm::GlobalValue::ExternalLinkage, nullptr, Name);
1697 CharUnits Align = CGM.getIntAlign();
1698 llvm::Value *Offset =
1699 CGF.Builder.CreateAlignedLoad(IntTy, IvarOffsetPointer, Align);
1700 if (Offset->getType() != PtrDiffTy)
1701 Offset = CGF.Builder.CreateZExtOrBitCast(Offset, PtrDiffTy);
1702 return Offset;
1703 }
1704 void GenerateClass(const ObjCImplementationDecl *OID) override {
1705 ASTContext &Context = CGM.getContext();
1706 bool IsCOFF = CGM.getTriple().isOSBinFormatCOFF();
1707
1708 // Get the class name
1709 ObjCInterfaceDecl *classDecl =
1710 const_cast<ObjCInterfaceDecl *>(OID->getClassInterface());
1711 std::string className = classDecl->getNameAsString();
1712 auto *classNameConstant = MakeConstantString(className);
1713
1714 ConstantInitBuilder builder(CGM);
1715 auto metaclassFields = builder.beginStruct();
1716 // struct objc_class *isa;
1717 metaclassFields.addNullPointer(PtrTy);
1718 // struct objc_class *super_class;
1719 metaclassFields.addNullPointer(PtrTy);
1720 // const char *name;
1721 metaclassFields.add(classNameConstant);
1722 // long version;
1723 metaclassFields.addInt(LongTy, 0);
1724 // unsigned long info;
1725 // objc_class_flag_meta
1726 metaclassFields.addInt(LongTy, 1);
1727 // long instance_size;
1728 // Setting this to zero is consistent with the older ABI, but it might be
1729 // more sensible to set this to sizeof(struct objc_class)
1730 metaclassFields.addInt(LongTy, 0);
1731 // struct objc_ivar_list *ivars;
1732 metaclassFields.addNullPointer(PtrTy);
1733 // struct objc_method_list *methods
1734 // FIXME: Almost identical code is copied and pasted below for the
1735 // class, but refactoring it cleanly requires C++14 generic lambdas.
1736 if (OID->classmeth_begin() == OID->classmeth_end())
1737 metaclassFields.addNullPointer(PtrTy);
1738 else {
1739 SmallVector<ObjCMethodDecl*, 16> ClassMethods;
1740 ClassMethods.insert(ClassMethods.begin(), OID->classmeth_begin(),
1741 OID->classmeth_end());
1742 metaclassFields.addBitCast(
1743 GenerateMethodList(className, "", ClassMethods, true),
1744 PtrTy);
1745 }
1746 // void *dtable;
1747 metaclassFields.addNullPointer(PtrTy);
1748 // IMP cxx_construct;
1749 metaclassFields.addNullPointer(PtrTy);
1750 // IMP cxx_destruct;
1751 metaclassFields.addNullPointer(PtrTy);
1752 // struct objc_class *subclass_list
1753 metaclassFields.addNullPointer(PtrTy);
1754 // struct objc_class *sibling_class
1755 metaclassFields.addNullPointer(PtrTy);
1756 // struct objc_protocol_list *protocols;
1757 metaclassFields.addNullPointer(PtrTy);
1758 // struct reference_list *extra_data;
1759 metaclassFields.addNullPointer(PtrTy);
1760 // long abi_version;
1761 metaclassFields.addInt(LongTy, 0);
1762 // struct objc_property_list *properties
1763 metaclassFields.add(GeneratePropertyList(OID, classDecl, /*isClassProperty*/true));
1764
1765 auto *metaclass = metaclassFields.finishAndCreateGlobal(
1766 ManglePublicSymbol("OBJC_METACLASS_") + className,
1767 CGM.getPointerAlign());
1768
1769 auto classFields = builder.beginStruct();
1770 // struct objc_class *isa;
1771 classFields.add(metaclass);
1772 // struct objc_class *super_class;
1773 // Get the superclass name.
1774 const ObjCInterfaceDecl * SuperClassDecl =
1775 OID->getClassInterface()->getSuperClass();
1776 llvm::Constant *SuperClass = nullptr;
1777 if (SuperClassDecl) {
1778 auto SuperClassName = SymbolForClass(SuperClassDecl->getNameAsString());
1779 SuperClass = TheModule.getNamedGlobal(SuperClassName);
1780 if (!SuperClass)
1781 {
1782 SuperClass = new llvm::GlobalVariable(TheModule, PtrTy, false,
1783 llvm::GlobalValue::ExternalLinkage, nullptr, SuperClassName);
1784 if (IsCOFF) {
1785 auto Storage = llvm::GlobalValue::DefaultStorageClass;
1786 if (SuperClassDecl->hasAttr<DLLImportAttr>())
1787 Storage = llvm::GlobalValue::DLLImportStorageClass;
1788 else if (SuperClassDecl->hasAttr<DLLExportAttr>())
1789 Storage = llvm::GlobalValue::DLLExportStorageClass;
1790
1791 cast<llvm::GlobalValue>(SuperClass)->setDLLStorageClass(Storage);
1792 }
1793 }
1794 if (!IsCOFF)
1795 classFields.add(llvm::ConstantExpr::getBitCast(SuperClass, PtrTy));
1796 else
1797 classFields.addNullPointer(PtrTy);
1798 } else
1799 classFields.addNullPointer(PtrTy);
1800 // const char *name;
1801 classFields.add(classNameConstant);
1802 // long version;
1803 classFields.addInt(LongTy, 0);
1804 // unsigned long info;
1805 // !objc_class_flag_meta
1806 classFields.addInt(LongTy, 0);
1807 // long instance_size;
1808 int superInstanceSize = !SuperClassDecl ? 0 :
1809 Context.getASTObjCInterfaceLayout(SuperClassDecl).getSize().getQuantity();
1810 // Instance size is negative for classes that have not yet had their ivar
1811 // layout calculated.
1812 classFields.addInt(LongTy,
1813 0 - (Context.getASTObjCImplementationLayout(OID).getSize().getQuantity() -
1814 superInstanceSize));
1815
1816 if (classDecl->all_declared_ivar_begin() == nullptr)
1817 classFields.addNullPointer(PtrTy);
1818 else {
1819 int ivar_count = 0;
1820 for (const ObjCIvarDecl *IVD = classDecl->all_declared_ivar_begin(); IVD;
1821 IVD = IVD->getNextIvar()) ivar_count++;
1822 llvm::DataLayout td(&TheModule);
1823 // struct objc_ivar_list *ivars;
1824 ConstantInitBuilder b(CGM);
1825 auto ivarListBuilder = b.beginStruct();
1826 // int count;
1827 ivarListBuilder.addInt(IntTy, ivar_count);
1828 // size_t size;
1829 llvm::StructType *ObjCIvarTy = llvm::StructType::get(
1830 PtrToInt8Ty,
1831 PtrToInt8Ty,
1832 PtrToInt8Ty,
1833 Int32Ty,
1834 Int32Ty);
1835 ivarListBuilder.addInt(SizeTy, td.getTypeSizeInBits(ObjCIvarTy) /
1836 CGM.getContext().getCharWidth());
1837 // struct objc_ivar ivars[]
1838 auto ivarArrayBuilder = ivarListBuilder.beginArray();
1839 for (const ObjCIvarDecl *IVD = classDecl->all_declared_ivar_begin(); IVD;
1840 IVD = IVD->getNextIvar()) {
1841 auto ivarTy = IVD->getType();
1842 auto ivarBuilder = ivarArrayBuilder.beginStruct();
1843 // const char *name;
1844 ivarBuilder.add(MakeConstantString(IVD->getNameAsString()));
1845 // const char *type;
1846 std::string TypeStr;
1847 //Context.getObjCEncodingForType(ivarTy, TypeStr, IVD, true);
1848 Context.getObjCEncodingForMethodParameter(Decl::OBJC_TQ_None, ivarTy, TypeStr, true);
1849 ivarBuilder.add(MakeConstantString(TypeStr));
1850 // int *offset;
1851 uint64_t BaseOffset = ComputeIvarBaseOffset(CGM, OID, IVD);
1852 uint64_t Offset = BaseOffset - superInstanceSize;
1853 llvm::Constant *OffsetValue = llvm::ConstantInt::get(IntTy, Offset);
1854 std::string OffsetName = GetIVarOffsetVariableName(classDecl, IVD);
1855 llvm::GlobalVariable *OffsetVar = TheModule.getGlobalVariable(OffsetName);
1856 if (OffsetVar)
1857 OffsetVar->setInitializer(OffsetValue);
1858 else
1859 OffsetVar = new llvm::GlobalVariable(TheModule, IntTy,
1860 false, llvm::GlobalValue::ExternalLinkage,
1861 OffsetValue, OffsetName);
1862 auto ivarVisibility =
1863 (IVD->getAccessControl() == ObjCIvarDecl::Private ||
1864 IVD->getAccessControl() == ObjCIvarDecl::Package ||
1865 classDecl->getVisibility() == HiddenVisibility) ?
1866 llvm::GlobalValue::HiddenVisibility :
1867 llvm::GlobalValue::DefaultVisibility;
1868 OffsetVar->setVisibility(ivarVisibility);
1869 ivarBuilder.add(OffsetVar);
1870 // Ivar size
1871 ivarBuilder.addInt(Int32Ty,
1872 CGM.getContext().getTypeSizeInChars(ivarTy).getQuantity());
1873 // Alignment will be stored as a base-2 log of the alignment.
1874 unsigned align =
1875 llvm::Log2_32(Context.getTypeAlignInChars(ivarTy).getQuantity());
1876 // Objects that require more than 2^64-byte alignment should be impossible!
1877 assert(align < 64)(static_cast<void> (0));
1878 // uint32_t flags;
1879 // Bits 0-1 are ownership.
1880 // Bit 2 indicates an extended type encoding
1881 // Bits 3-8 contain log2(aligment)
1882 ivarBuilder.addInt(Int32Ty,
1883 (align << 3) | (1<<2) |
1884 FlagsForOwnership(ivarTy.getQualifiers().getObjCLifetime()));
1885 ivarBuilder.finishAndAddTo(ivarArrayBuilder);
1886 }
1887 ivarArrayBuilder.finishAndAddTo(ivarListBuilder);
1888 auto ivarList = ivarListBuilder.finishAndCreateGlobal(".objc_ivar_list",
1889 CGM.getPointerAlign(), /*constant*/ false,
1890 llvm::GlobalValue::PrivateLinkage);
1891 classFields.add(ivarList);
1892 }
1893 // struct objc_method_list *methods
1894 SmallVector<const ObjCMethodDecl*, 16> InstanceMethods;
1895 InstanceMethods.insert(InstanceMethods.begin(), OID->instmeth_begin(),
1896 OID->instmeth_end());
1897 for (auto *propImpl : OID->property_impls())
1898 if (propImpl->getPropertyImplementation() ==
1899 ObjCPropertyImplDecl::Synthesize) {
1900 auto addIfExists = [&](const ObjCMethodDecl *OMD) {
1901 if (OMD && OMD->hasBody())
1902 InstanceMethods.push_back(OMD);
1903 };
1904 addIfExists(propImpl->getGetterMethodDecl());
1905 addIfExists(propImpl->getSetterMethodDecl());
1906 }
1907
1908 if (InstanceMethods.size() == 0)
1909 classFields.addNullPointer(PtrTy);
1910 else
1911 classFields.addBitCast(
1912 GenerateMethodList(className, "", InstanceMethods, false),
1913 PtrTy);
1914 // void *dtable;
1915 classFields.addNullPointer(PtrTy);
1916 // IMP cxx_construct;
1917 classFields.addNullPointer(PtrTy);
1918 // IMP cxx_destruct;
1919 classFields.addNullPointer(PtrTy);
1920 // struct objc_class *subclass_list
1921 classFields.addNullPointer(PtrTy);
1922 // struct objc_class *sibling_class
1923 classFields.addNullPointer(PtrTy);
1924 // struct objc_protocol_list *protocols;
1925 auto RuntimeProtocols = GetRuntimeProtocolList(classDecl->protocol_begin(),
1926 classDecl->protocol_end());
1927 SmallVector<llvm::Constant *, 16> Protocols;
1928 for (const auto *I : RuntimeProtocols)
1929 Protocols.push_back(
1930 llvm::ConstantExpr::getBitCast(GenerateProtocolRef(I),
1931 ProtocolPtrTy));
1932 if (Protocols.empty())
1933 classFields.addNullPointer(PtrTy);
1934 else
1935 classFields.add(GenerateProtocolList(Protocols));
1936 // struct reference_list *extra_data;
1937 classFields.addNullPointer(PtrTy);
1938 // long abi_version;
1939 classFields.addInt(LongTy, 0);
1940 // struct objc_property_list *properties
1941 classFields.add(GeneratePropertyList(OID, classDecl));
1942
1943 llvm::GlobalVariable *classStruct =
1944 classFields.finishAndCreateGlobal(SymbolForClass(className),
1945 CGM.getPointerAlign(), false, llvm::GlobalValue::ExternalLinkage);
1946
1947 auto *classRefSymbol = GetClassVar(className);
1948 classRefSymbol->setSection(sectionName<ClassReferenceSection>());
1949 classRefSymbol->setInitializer(llvm::ConstantExpr::getBitCast(classStruct, IdTy));
1950
1951 if (IsCOFF) {
1952 // we can't import a class struct.
1953 if (OID->getClassInterface()->hasAttr<DLLExportAttr>()) {
1954 classStruct->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
1955 cast<llvm::GlobalValue>(classRefSymbol)->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
1956 }
1957
1958 if (SuperClass) {
1959 std::pair<llvm::GlobalVariable*, int> v{classStruct, 1};
1960 EarlyInitList.emplace_back(std::string(SuperClass->getName()),
1961 std::move(v));
1962 }
1963
1964 }
1965
1966
1967 // Resolve the class aliases, if they exist.
1968 // FIXME: Class pointer aliases shouldn't exist!
1969 if (ClassPtrAlias) {
1970 ClassPtrAlias->replaceAllUsesWith(
1971 llvm::ConstantExpr::getBitCast(classStruct, IdTy));
1972 ClassPtrAlias->eraseFromParent();
1973 ClassPtrAlias = nullptr;
1974 }
1975 if (auto Placeholder =
1976 TheModule.getNamedGlobal(SymbolForClass(className)))
1977 if (Placeholder != classStruct) {
1978 Placeholder->replaceAllUsesWith(
1979 llvm::ConstantExpr::getBitCast(classStruct, Placeholder->getType()));
1980 Placeholder->eraseFromParent();
1981 classStruct->setName(SymbolForClass(className));
1982 }
1983 if (MetaClassPtrAlias) {
1984 MetaClassPtrAlias->replaceAllUsesWith(
1985 llvm::ConstantExpr::getBitCast(metaclass, IdTy));
1986 MetaClassPtrAlias->eraseFromParent();
1987 MetaClassPtrAlias = nullptr;
1988 }
1989 assert(classStruct->getName() == SymbolForClass(className))(static_cast<void> (0));
1990
1991 auto classInitRef = new llvm::GlobalVariable(TheModule,
1992 classStruct->getType(), false, llvm::GlobalValue::ExternalLinkage,
1993 classStruct, ManglePublicSymbol("OBJC_INIT_CLASS_") + className);
1994 classInitRef->setSection(sectionName<ClassSection>());
1995 CGM.addUsedGlobal(classInitRef);
1996
1997 EmittedClass = true;
1998 }
1999 public:
2000 CGObjCGNUstep2(CodeGenModule &Mod) : CGObjCGNUstep(Mod, 10, 4, 2) {
2001 MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy,
2002 PtrToObjCSuperTy, SelectorTy);
2003 // struct objc_property
2004 // {
2005 // const char *name;
2006 // const char *attributes;
2007 // const char *type;
2008 // SEL getter;
2009 // SEL setter;
2010 // }
2011 PropertyMetadataTy =
2012 llvm::StructType::get(CGM.getLLVMContext(),
2013 { PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty });
2014 }
2015
2016};
2017
2018const char *const CGObjCGNUstep2::SectionsBaseNames[8] =
2019{
2020"__objc_selectors",
2021"__objc_classes",
2022"__objc_class_refs",
2023"__objc_cats",
2024"__objc_protocols",
2025"__objc_protocol_refs",
2026"__objc_class_aliases",
2027"__objc_constant_string"
2028};
2029
2030const char *const CGObjCGNUstep2::PECOFFSectionsBaseNames[8] =
2031{
2032".objcrt$SEL",
2033".objcrt$CLS",
2034".objcrt$CLR",
2035".objcrt$CAT",
2036".objcrt$PCL",
2037".objcrt$PCR",
2038".objcrt$CAL",
2039".objcrt$STR"
2040};
2041
2042/// Support for the ObjFW runtime.
2043class CGObjCObjFW: public CGObjCGNU {
2044protected:
2045 /// The GCC ABI message lookup function. Returns an IMP pointing to the
2046 /// method implementation for this message.
2047 LazyRuntimeFunction MsgLookupFn;
2048 /// stret lookup function. While this does not seem to make sense at the
2049 /// first look, this is required to call the correct forwarding function.
2050 LazyRuntimeFunction MsgLookupFnSRet;
2051 /// The GCC ABI superclass message lookup function. Takes a pointer to a
2052 /// structure describing the receiver and the class, and a selector as
2053 /// arguments. Returns the IMP for the corresponding method.
2054 LazyRuntimeFunction MsgLookupSuperFn, MsgLookupSuperFnSRet;
2055
2056 llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver,
2057 llvm::Value *cmd, llvm::MDNode *node,
2058 MessageSendInfo &MSI) override {
2059 CGBuilderTy &Builder = CGF.Builder;
2060 llvm::Value *args[] = {
2061 EnforceType(Builder, Receiver, IdTy),
2062 EnforceType(Builder, cmd, SelectorTy) };
2063
2064 llvm::CallBase *imp;
2065 if (CGM.ReturnTypeUsesSRet(MSI.CallInfo))
2066 imp = CGF.EmitRuntimeCallOrInvoke(MsgLookupFnSRet, args);
2067 else
2068 imp = CGF.EmitRuntimeCallOrInvoke(MsgLookupFn, args);
2069
2070 imp->setMetadata(msgSendMDKind, node);
2071 return imp;
2072 }
2073
2074 llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, Address ObjCSuper,
2075 llvm::Value *cmd, MessageSendInfo &MSI) override {
2076 CGBuilderTy &Builder = CGF.Builder;
2077 llvm::Value *lookupArgs[] = {
2078 EnforceType(Builder, ObjCSuper.getPointer(), PtrToObjCSuperTy), cmd,
2079 };
2080
2081 if (CGM.ReturnTypeUsesSRet(MSI.CallInfo))
2082 return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFnSRet, lookupArgs);
2083 else
2084 return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFn, lookupArgs);
2085 }
2086
2087 llvm::Value *GetClassNamed(CodeGenFunction &CGF, const std::string &Name,
2088 bool isWeak) override {
2089 if (isWeak)
2090 return CGObjCGNU::GetClassNamed(CGF, Name, isWeak);
2091
2092 EmitClassRef(Name);
2093 std::string SymbolName = "_OBJC_CLASS_" + Name;
2094 llvm::GlobalVariable *ClassSymbol = TheModule.getGlobalVariable(SymbolName);
2095 if (!ClassSymbol)
2096 ClassSymbol = new llvm::GlobalVariable(TheModule, LongTy, false,
2097 llvm::GlobalValue::ExternalLinkage,
2098 nullptr, SymbolName);
2099 return ClassSymbol;
2100 }
2101
2102public:
2103 CGObjCObjFW(CodeGenModule &Mod): CGObjCGNU(Mod, 9, 3) {
2104 // IMP objc_msg_lookup(id, SEL);
2105 MsgLookupFn.init(&CGM, "objc_msg_lookup", IMPTy, IdTy, SelectorTy);
2106 MsgLookupFnSRet.init(&CGM, "objc_msg_lookup_stret", IMPTy, IdTy,
2107 SelectorTy);
2108 // IMP objc_msg_lookup_super(struct objc_super*, SEL);
2109 MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy,
2110 PtrToObjCSuperTy, SelectorTy);
2111 MsgLookupSuperFnSRet.init(&CGM, "objc_msg_lookup_super_stret", IMPTy,
2112 PtrToObjCSuperTy, SelectorTy);
2113 }
2114};
2115} // end anonymous namespace
2116
2117/// Emits a reference to a dummy variable which is emitted with each class.
2118/// This ensures that a linker error will be generated when trying to link
2119/// together modules where a referenced class is not defined.
2120void CGObjCGNU::EmitClassRef(const std::string &className) {
2121 std::string symbolRef = "__objc_class_ref_" + className;
2122 // Don't emit two copies of the same symbol
2123 if (TheModule.getGlobalVariable(symbolRef))
2124 return;
2125 std::string symbolName = "__objc_class_name_" + className;
2126 llvm::GlobalVariable *ClassSymbol = TheModule.getGlobalVariable(symbolName);
2127 if (!ClassSymbol) {
2128 ClassSymbol = new llvm::GlobalVariable(TheModule, LongTy, false,
2129 llvm::GlobalValue::ExternalLinkage,
2130 nullptr, symbolName);
2131 }
2132 new llvm::GlobalVariable(TheModule, ClassSymbol->getType(), true,
2133 llvm::GlobalValue::WeakAnyLinkage, ClassSymbol, symbolRef);
2134}
2135
2136CGObjCGNU::CGObjCGNU(CodeGenModule &cgm, unsigned runtimeABIVersion,
2137 unsigned protocolClassVersion, unsigned classABI)
2138 : CGObjCRuntime(cgm), TheModule(CGM.getModule()),
2139 VMContext(cgm.getLLVMContext()), ClassPtrAlias(nullptr),
2140 MetaClassPtrAlias(nullptr), RuntimeVersion(runtimeABIVersion),
2141 ProtocolVersion(protocolClassVersion), ClassABIVersion(classABI) {
2142
2143 msgSendMDKind = VMContext.getMDKindID("GNUObjCMessageSend");
2144 usesSEHExceptions =
2145 cgm.getContext().getTargetInfo().getTriple().isWindowsMSVCEnvironment();
2146
2147 CodeGenTypes &Types = CGM.getTypes();
2148 IntTy = cast<llvm::IntegerType>(
2149 Types.ConvertType(CGM.getContext().IntTy));
2150 LongTy = cast<llvm::IntegerType>(
2151 Types.ConvertType(CGM.getContext().LongTy));
2152 SizeTy = cast<llvm::IntegerType>(
2153 Types.ConvertType(CGM.getContext().getSizeType()));
2154 PtrDiffTy = cast<llvm::IntegerType>(
2155 Types.ConvertType(CGM.getContext().getPointerDiffType()));
2156 BoolTy = CGM.getTypes().ConvertType(CGM.getContext().BoolTy);
2157
2158 Int8Ty = llvm::Type::getInt8Ty(VMContext);
2159 // C string type. Used in lots of places.
2160 PtrToInt8Ty = llvm::PointerType::getUnqual(Int8Ty);
2161 ProtocolPtrTy = llvm::PointerType::getUnqual(
2162 Types.ConvertType(CGM.getContext().getObjCProtoType()));
2163
2164 Zeros[0] = llvm::ConstantInt::get(LongTy, 0);
2165 Zeros[1] = Zeros[0];
2166 NULLPtr = llvm::ConstantPointerNull::get(PtrToInt8Ty);
2167 // Get the selector Type.
2168 QualType selTy = CGM.getContext().getObjCSelType();
2169 if (QualType() == selTy) {
2170 SelectorTy = PtrToInt8Ty;
2171 } else {
2172 SelectorTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(selTy));
2173 }
2174
2175 PtrToIntTy = llvm::PointerType::getUnqual(IntTy);
2176 PtrTy = PtrToInt8Ty;
2177
2178 Int32Ty = llvm::Type::getInt32Ty(VMContext);
2179 Int64Ty = llvm::Type::getInt64Ty(VMContext);
2180
2181 IntPtrTy =
2182 CGM.getDataLayout().getPointerSizeInBits() == 32 ? Int32Ty : Int64Ty;
2183
2184 // Object type
2185 QualType UnqualIdTy = CGM.getContext().getObjCIdType();
2186 ASTIdTy = CanQualType();
2187 if (UnqualIdTy != QualType()) {
2188 ASTIdTy = CGM.getContext().getCanonicalType(UnqualIdTy);
2189 IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy));
2190 } else {
2191 IdTy = PtrToInt8Ty;
2192 }
2193 PtrToIdTy = llvm::PointerType::getUnqual(IdTy);
2194 ProtocolTy = llvm::StructType::get(IdTy,
2195 PtrToInt8Ty, // name
2196 PtrToInt8Ty, // protocols
2197 PtrToInt8Ty, // instance methods
2198 PtrToInt8Ty, // class methods
2199 PtrToInt8Ty, // optional instance methods
2200 PtrToInt8Ty, // optional class methods
2201 PtrToInt8Ty, // properties
2202 PtrToInt8Ty);// optional properties
2203
2204 // struct objc_property_gsv1
2205 // {
2206 // const char *name;
2207 // char attributes;
2208 // char attributes2;
2209 // char unused1;
2210 // char unused2;
2211 // const char *getter_name;
2212 // const char *getter_types;
2213 // const char *setter_name;
2214 // const char *setter_types;
2215 // }
2216 PropertyMetadataTy = llvm::StructType::get(CGM.getLLVMContext(), {
2217 PtrToInt8Ty, Int8Ty, Int8Ty, Int8Ty, Int8Ty, PtrToInt8Ty, PtrToInt8Ty,
2218 PtrToInt8Ty, PtrToInt8Ty });
2219
2220 ObjCSuperTy = llvm::StructType::get(IdTy, IdTy);
2221 PtrToObjCSuperTy = llvm::PointerType::getUnqual(ObjCSuperTy);
2222
2223 llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
2224
2225 // void objc_exception_throw(id);
2226 ExceptionThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy);
2227 ExceptionReThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy);
2228 // int objc_sync_enter(id);
2229 SyncEnterFn.init(&CGM, "objc_sync_enter", IntTy, IdTy);
2230 // int objc_sync_exit(id);
2231 SyncExitFn.init(&CGM, "objc_sync_exit", IntTy, IdTy);
2232
2233 // void objc_enumerationMutation (id)
2234 EnumerationMutationFn.init(&CGM, "objc_enumerationMutation", VoidTy, IdTy);
2235
2236 // id objc_getProperty(id, SEL, ptrdiff_t, BOOL)
2237 GetPropertyFn.init(&CGM, "objc_getProperty", IdTy, IdTy, SelectorTy,
2238 PtrDiffTy, BoolTy);
2239 // void objc_setProperty(id, SEL, ptrdiff_t, id, BOOL, BOOL)
2240 SetPropertyFn.init(&CGM, "objc_setProperty", VoidTy, IdTy, SelectorTy,
2241 PtrDiffTy, IdTy, BoolTy, BoolTy);
2242 // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL)
2243 GetStructPropertyFn.init(&CGM, "objc_getPropertyStruct", VoidTy, PtrTy, PtrTy,
2244 PtrDiffTy, BoolTy, BoolTy);
2245 // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL)
2246 SetStructPropertyFn.init(&CGM, "objc_setPropertyStruct", VoidTy, PtrTy, PtrTy,
2247 PtrDiffTy, BoolTy, BoolTy);
2248
2249 // IMP type
2250 llvm::Type *IMPArgs[] = { IdTy, SelectorTy };
2251 IMPTy = llvm::PointerType::getUnqual(llvm::FunctionType::get(IdTy, IMPArgs,
2252 true));
2253
2254 const LangOptions &Opts = CGM.getLangOpts();
2255 if ((Opts.getGC() != LangOptions::NonGC) || Opts.ObjCAutoRefCount)
2256 RuntimeVersion = 10;
2257
2258 // Don't bother initialising the GC stuff unless we're compiling in GC mode
2259 if (Opts.getGC() != LangOptions::NonGC) {
2260 // This is a bit of an hack. We should sort this out by having a proper
2261 // CGObjCGNUstep subclass for GC, but we may want to really support the old
2262 // ABI and GC added in ObjectiveC2.framework, so we fudge it a bit for now
2263 // Get selectors needed in GC mode
2264 RetainSel = GetNullarySelector("retain", CGM.getContext());
2265 ReleaseSel = GetNullarySelector("release", CGM.getContext());
2266 AutoreleaseSel = GetNullarySelector("autorelease", CGM.getContext());
2267
2268 // Get functions needed in GC mode
2269
2270 // id objc_assign_ivar(id, id, ptrdiff_t);
2271 IvarAssignFn.init(&CGM, "objc_assign_ivar", IdTy, IdTy, IdTy, PtrDiffTy);
2272 // id objc_assign_strongCast (id, id*)
2273 StrongCastAssignFn.init(&CGM, "objc_assign_strongCast", IdTy, IdTy,
2274 PtrToIdTy);
2275 // id objc_assign_global(id, id*);
2276 GlobalAssignFn.init(&CGM, "objc_assign_global", IdTy, IdTy, PtrToIdTy);
2277 // id objc_assign_weak(id, id*);
2278 WeakAssignFn.init(&CGM, "objc_assign_weak", IdTy, IdTy, PtrToIdTy);
2279 // id objc_read_weak(id*);
2280 WeakReadFn.init(&CGM, "objc_read_weak", IdTy, PtrToIdTy);
2281 // void *objc_memmove_collectable(void*, void *, size_t);
2282 MemMoveFn.init(&CGM, "objc_memmove_collectable", PtrTy, PtrTy, PtrTy,
2283 SizeTy);
2284 }
2285}
2286
2287llvm::Value *CGObjCGNU::GetClassNamed(CodeGenFunction &CGF,
2288 const std::string &Name, bool isWeak) {
2289 llvm::Constant *ClassName = MakeConstantString(Name);
2290 // With the incompatible ABI, this will need to be replaced with a direct
2291 // reference to the class symbol. For the compatible nonfragile ABI we are
2292 // still performing this lookup at run time but emitting the symbol for the
2293 // class externally so that we can make the switch later.
2294 //
2295 // Libobjc2 contains an LLVM pass that replaces calls to objc_lookup_class
2296 // with memoized versions or with static references if it's safe to do so.
2297 if (!isWeak)
2298 EmitClassRef(Name);
2299
2300 llvm::FunctionCallee ClassLookupFn = CGM.CreateRuntimeFunction(
2301 llvm::FunctionType::get(IdTy, PtrToInt8Ty, true), "objc_lookup_class");
2302 return CGF.EmitNounwindRuntimeCall(ClassLookupFn, ClassName);
2303}
2304
2305// This has to perform the lookup every time, since posing and related
2306// techniques can modify the name -> class mapping.
2307llvm::Value *CGObjCGNU::GetClass(CodeGenFunction &CGF,
2308 const ObjCInterfaceDecl *OID) {
2309 auto *Value =
2310 GetClassNamed(CGF, OID->getNameAsString(), OID->isWeakImported());
2311 if (auto *ClassSymbol = dyn_cast<llvm::GlobalVariable>(Value))
2312 CGM.setGVProperties(ClassSymbol, OID);
2313 return Value;
2314}
2315
2316llvm::Value *CGObjCGNU::EmitNSAutoreleasePoolClassRef(CodeGenFunction &CGF) {
2317 auto *Value = GetClassNamed(CGF, "NSAutoreleasePool", false);
2318 if (CGM.getTriple().isOSBinFormatCOFF()) {
2319 if (auto *ClassSymbol = dyn_cast<llvm::GlobalVariable>(Value)) {
2320 IdentifierInfo &II = CGF.CGM.getContext().Idents.get("NSAutoreleasePool");
2321 TranslationUnitDecl *TUDecl = CGM.getContext().getTranslationUnitDecl();
2322 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl);
2323
2324 const VarDecl *VD = nullptr;
2325 for (const auto *Result : DC->lookup(&II))
2326 if ((VD = dyn_cast<VarDecl>(Result)))
2327 break;
2328
2329 CGM.setGVProperties(ClassSymbol, VD);
2330 }
2331 }
2332 return Value;
2333}
2334
2335llvm::Value *CGObjCGNU::GetTypedSelector(CodeGenFunction &CGF, Selector Sel,
2336 const std::string &TypeEncoding) {
2337 SmallVectorImpl<TypedSelector> &Types = SelectorTable[Sel];
2338 llvm::GlobalAlias *SelValue = nullptr;
2339
2340 for (SmallVectorImpl<TypedSelector>::iterator i = Types.begin(),
2341 e = Types.end() ; i!=e ; i++) {
2342 if (i->first == TypeEncoding) {
2343 SelValue = i->second;
2344 break;
2345 }
2346 }
2347 if (!SelValue) {
2348 SelValue = llvm::GlobalAlias::create(
2349 SelectorTy->getElementType(), 0, llvm::GlobalValue::PrivateLinkage,
2350 ".objc_selector_" + Sel.getAsString(), &TheModule);
2351 Types.emplace_back(TypeEncoding, SelValue);
2352 }
2353
2354 return SelValue;
2355}
2356
2357Address CGObjCGNU::GetAddrOfSelector(CodeGenFunction &CGF, Selector Sel) {
2358 llvm::Value *SelValue = GetSelector(CGF, Sel);
2359
2360 // Store it to a temporary. Does this satisfy the semantics of
2361 // GetAddrOfSelector? Hopefully.
2362 Address tmp = CGF.CreateTempAlloca(SelValue->getType(),
2363 CGF.getPointerAlign());
2364 CGF.Builder.CreateStore(SelValue, tmp);
2365 return tmp;
2366}
2367
2368llvm::Value *CGObjCGNU::GetSelector(CodeGenFunction &CGF, Selector Sel) {
2369 return GetTypedSelector(CGF, Sel, std::string());
2370}
2371
2372llvm::Value *CGObjCGNU::GetSelector(CodeGenFunction &CGF,
2373 const ObjCMethodDecl *Method) {
2374 std::string SelTypes = CGM.getContext().getObjCEncodingForMethodDecl(Method);
2375 return GetTypedSelector(CGF, Method->getSelector(), SelTypes);
2376}
2377
2378llvm::Constant *CGObjCGNU::GetEHType(QualType T) {
2379 if (T->isObjCIdType() || T->isObjCQualifiedIdType()) {
2380 // With the old ABI, there was only one kind of catchall, which broke
2381 // foreign exceptions. With the new ABI, we use __objc_id_typeinfo as
2382 // a pointer indicating object catchalls, and NULL to indicate real
2383 // catchalls
2384 if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
2385 return MakeConstantString("@id");
2386 } else {
2387 return nullptr;
2388 }
2389 }
2390
2391 // All other types should be Objective-C interface pointer types.
2392 const ObjCObjectPointerType *OPT = T->getAs<ObjCObjectPointerType>();
2393 assert(OPT && "Invalid @catch type.")(static_cast<void> (0));
2394 const ObjCInterfaceDecl *IDecl = OPT->getObjectType()->getInterface();
2395 assert(IDecl && "Invalid @catch type.")(static_cast<void> (0));
2396 return MakeConstantString(IDecl->getIdentifier()->getName());
2397}
2398
2399llvm::Constant *CGObjCGNUstep::GetEHType(QualType T) {
2400 if (usesSEHExceptions)
1
Assuming field 'usesSEHExceptions' is false
2
Taking false branch
2401 return CGM.getCXXABI().getAddrOfRTTIDescriptor(T);
2402
2403 if (!CGM.getLangOpts().CPlusPlus)
3
Assuming field 'CPlusPlus' is not equal to 0
2404 return CGObjCGNU::GetEHType(T);
2405
2406 // For Objective-C++, we want to provide the ability to catch both C++ and
2407 // Objective-C objects in the same function.
2408
2409 // There's a particular fixed type info for 'id'.
2410 if (T->isObjCIdType() ||
4
Calling 'Type::isObjCIdType'
8
Returning from 'Type::isObjCIdType'
14
Taking false branch
2411 T->isObjCQualifiedIdType()) {
9
Calling 'Type::isObjCQualifiedIdType'
13
Returning from 'Type::isObjCQualifiedIdType'
2412 llvm::Constant *IDEHType =
2413 CGM.getModule().getGlobalVariable("__objc_id_type_info");
2414 if (!IDEHType)
2415 IDEHType =
2416 new llvm::GlobalVariable(CGM.getModule(), PtrToInt8Ty,
2417 false,
2418 llvm::GlobalValue::ExternalLinkage,
2419 nullptr, "__objc_id_type_info");
2420 return llvm::ConstantExpr::getBitCast(IDEHType, PtrToInt8Ty);
2421 }
2422
2423 const ObjCObjectPointerType *PT =
16
'PT' initialized to a null pointer value
2424 T->getAs<ObjCObjectPointerType>();
15
Assuming the object is not a 'ObjCObjectPointerType'
2425 assert(PT && "Invalid @catch type.")(static_cast<void> (0));
2426 const ObjCInterfaceType *IT = PT->getInterfaceType();
17
Called C++ object pointer is null
2427 assert(IT && "Invalid @catch type.")(static_cast<void> (0));
2428 std::string className =
2429 std::string(IT->getDecl()->getIdentifier()->getName());
2430
2431 std::string typeinfoName = "__objc_eh_typeinfo_" + className;
2432
2433 // Return the existing typeinfo if it exists
2434 llvm::Constant *typeinfo = TheModule.getGlobalVariable(typeinfoName);
2435 if (typeinfo)
2436 return llvm::ConstantExpr::getBitCast(typeinfo, PtrToInt8Ty);
2437
2438 // Otherwise create it.
2439
2440 // vtable for gnustep::libobjc::__objc_class_type_info
2441 // It's quite ugly hard-coding this. Ideally we'd generate it using the host
2442 // platform's name mangling.
2443 const char *vtableName = "_ZTVN7gnustep7libobjc22__objc_class_type_infoE";
2444 auto *Vtable = TheModule.getGlobalVariable(vtableName);
2445 if (!Vtable) {
2446 Vtable = new llvm::GlobalVariable(TheModule, PtrToInt8Ty, true,
2447 llvm::GlobalValue::ExternalLinkage,
2448 nullptr, vtableName);
2449 }
2450 llvm::Constant *Two = llvm::ConstantInt::get(IntTy, 2);
2451 auto *BVtable = llvm::ConstantExpr::getBitCast(
2452 llvm::ConstantExpr::getGetElementPtr(Vtable->getValueType(), Vtable, Two),
2453 PtrToInt8Ty);
2454
2455 llvm::Constant *typeName =
2456 ExportUniqueString(className, "__objc_eh_typename_");
2457
2458 ConstantInitBuilder builder(CGM);
2459 auto fields = builder.beginStruct();
2460 fields.add(BVtable);
2461 fields.add(typeName);
2462 llvm::Constant *TI =
2463 fields.finishAndCreateGlobal("__objc_eh_typeinfo_" + className,
2464 CGM.getPointerAlign(),
2465 /*constant*/ false,
2466 llvm::GlobalValue::LinkOnceODRLinkage);
2467 return llvm::ConstantExpr::getBitCast(TI, PtrToInt8Ty);
2468}
2469
2470/// Generate an NSConstantString object.
2471ConstantAddress CGObjCGNU::GenerateConstantString(const StringLiteral *SL) {
2472
2473 std::string Str = SL->getString().str();
2474 CharUnits Align = CGM.getPointerAlign();
2475
2476 // Look for an existing one
2477 llvm::StringMap<llvm::Constant*>::iterator old = ObjCStrings.find(Str);
2478 if (old != ObjCStrings.end())
2479 return ConstantAddress(old->getValue(), Align);
2480
2481 StringRef StringClass = CGM.getLangOpts().ObjCConstantStringClass;
2482
2483 if (StringClass.empty()) StringClass = "NSConstantString";
2484
2485 std::string Sym = "_OBJC_CLASS_";
2486 Sym += StringClass;
2487
2488 llvm::Constant *isa = TheModule.getNamedGlobal(Sym);
2489
2490 if (!isa)
2491 isa = new llvm::GlobalVariable(TheModule, IdTy, /* isConstant */false,
2492 llvm::GlobalValue::ExternalWeakLinkage, nullptr, Sym);
2493 else if (isa->getType() != PtrToIdTy)
2494 isa = llvm::ConstantExpr::getBitCast(isa, PtrToIdTy);
2495
2496 ConstantInitBuilder Builder(CGM);
2497 auto Fields = Builder.beginStruct();
2498 Fields.add(isa);
2499 Fields.add(MakeConstantString(Str));
2500 Fields.addInt(IntTy, Str.size());
2501 llvm::Constant *ObjCStr =
2502 Fields.finishAndCreateGlobal(".objc_str", Align);
2503 ObjCStr = llvm::ConstantExpr::getBitCast(ObjCStr, PtrToInt8Ty);
2504 ObjCStrings[Str] = ObjCStr;
2505 ConstantStrings.push_back(ObjCStr);
2506 return ConstantAddress(ObjCStr, Align);
2507}
2508
2509///Generates a message send where the super is the receiver. This is a message
2510///send to self with special delivery semantics indicating which class's method
2511///should be called.
2512RValue
2513CGObjCGNU::GenerateMessageSendSuper(CodeGenFunction &CGF,
2514 ReturnValueSlot Return,
2515 QualType ResultType,
2516 Selector Sel,
2517 const ObjCInterfaceDecl *Class,
2518 bool isCategoryImpl,
2519 llvm::Value *Receiver,
2520 bool IsClassMessage,
2521 const CallArgList &CallArgs,
2522 const ObjCMethodDecl *Method) {
2523 CGBuilderTy &Builder = CGF.Builder;
2524 if (CGM.getLangOpts().getGC() == LangOptions::GCOnly) {
2525 if (Sel == RetainSel || Sel == AutoreleaseSel) {
2526 return RValue::get(EnforceType(Builder, Receiver,
2527 CGM.getTypes().ConvertType(ResultType)));
2528 }
2529 if (Sel == ReleaseSel) {
2530 return RValue::get(nullptr);
2531 }
2532 }
2533
2534 llvm::Value *cmd = GetSelector(CGF, Sel);
2535 CallArgList ActualArgs;
2536
2537 ActualArgs.add(RValue::get(EnforceType(Builder, Receiver, IdTy)), ASTIdTy);
2538 ActualArgs.add(RValue::get(cmd), CGF.getContext().getObjCSelType());
2539 ActualArgs.addFrom(CallArgs);
2540
2541 MessageSendInfo MSI = getMessageSendInfo(Method, ResultType, ActualArgs);
2542
2543 llvm::Value *ReceiverClass = nullptr;
2544 bool isV2ABI = isRuntime(ObjCRuntime::GNUstep, 2);
2545 if (isV2ABI) {
2546 ReceiverClass = GetClassNamed(CGF,
2547 Class->getSuperClass()->getNameAsString(), /*isWeak*/false);
2548 if (IsClassMessage) {
2549 // Load the isa pointer of the superclass is this is a class method.
2550 ReceiverClass = Builder.CreateBitCast(ReceiverClass,
2551 llvm::PointerType::getUnqual(IdTy));
2552 ReceiverClass =
2553 Builder.CreateAlignedLoad(IdTy, ReceiverClass, CGF.getPointerAlign());
2554 }
2555 ReceiverClass = EnforceType(Builder, ReceiverClass, IdTy);
2556 } else {
2557 if (isCategoryImpl) {
2558 llvm::FunctionCallee classLookupFunction = nullptr;
2559 if (IsClassMessage) {
2560 classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get(
2561 IdTy, PtrTy, true), "objc_get_meta_class");
2562 } else {
2563 classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get(
2564 IdTy, PtrTy, true), "objc_get_class");
2565 }
2566 ReceiverClass = Builder.CreateCall(classLookupFunction,
2567 MakeConstantString(Class->getNameAsString()));
2568 } else {
2569 // Set up global aliases for the metaclass or class pointer if they do not
2570 // already exist. These will are forward-references which will be set to
2571 // pointers to the class and metaclass structure created for the runtime
2572 // load function. To send a message to super, we look up the value of the
2573 // super_class pointer from either the class or metaclass structure.
2574 if (IsClassMessage) {
2575 if (!MetaClassPtrAlias) {
2576 MetaClassPtrAlias = llvm::GlobalAlias::create(
2577 IdTy->getElementType(), 0, llvm::GlobalValue::InternalLinkage,
2578 ".objc_metaclass_ref" + Class->getNameAsString(), &TheModule);
2579 }
2580 ReceiverClass = MetaClassPtrAlias;
2581 } else {
2582 if (!ClassPtrAlias) {
2583 ClassPtrAlias = llvm::GlobalAlias::create(
2584 IdTy->getElementType(), 0, llvm::GlobalValue::InternalLinkage,
2585 ".objc_class_ref" + Class->getNameAsString(), &TheModule);
2586 }
2587 ReceiverClass = ClassPtrAlias;
2588 }
2589 }
2590 // Cast the pointer to a simplified version of the class structure
2591 llvm::Type *CastTy = llvm::StructType::get(IdTy, IdTy);
2592 ReceiverClass = Builder.CreateBitCast(ReceiverClass,
2593 llvm::PointerType::getUnqual(CastTy));
2594 // Get the superclass pointer
2595 ReceiverClass = Builder.CreateStructGEP(CastTy, ReceiverClass, 1);
2596 // Load the superclass pointer
2597 ReceiverClass =
2598 Builder.CreateAlignedLoad(IdTy, ReceiverClass, CGF.getPointerAlign());
2599 }
2600 // Construct the structure used to look up the IMP
2601 llvm::StructType *ObjCSuperTy =
2602 llvm::StructType::get(Receiver->getType(), IdTy);
2603
2604 Address ObjCSuper = CGF.CreateTempAlloca(ObjCSuperTy,
2605 CGF.getPointerAlign());
2606
2607 Builder.CreateStore(Receiver, Builder.CreateStructGEP(ObjCSuper, 0));
2608 Builder.CreateStore(ReceiverClass, Builder.CreateStructGEP(ObjCSuper, 1));
2609
2610 ObjCSuper = EnforceType(Builder, ObjCSuper, PtrToObjCSuperTy);
2611
2612 // Get the IMP
2613 llvm::Value *imp = LookupIMPSuper(CGF, ObjCSuper, cmd, MSI);
2614 imp = EnforceType(Builder, imp, MSI.MessengerType);
2615
2616 llvm::Metadata *impMD[] = {
2617 llvm::MDString::get(VMContext, Sel.getAsString()),
2618 llvm::MDString::get(VMContext, Class->getSuperClass()->getNameAsString()),
2619 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
2620 llvm::Type::getInt1Ty(VMContext), IsClassMessage))};
2621 llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD);
2622
2623 CGCallee callee(CGCalleeInfo(), imp);
2624
2625 llvm::CallBase *call;
2626 RValue msgRet = CGF.EmitCall(MSI.CallInfo, callee, Return, ActualArgs, &call);
2627 call->setMetadata(msgSendMDKind, node);
2628 return msgRet;
2629}
2630
2631/// Generate code for a message send expression.
2632RValue
2633CGObjCGNU::GenerateMessageSend(CodeGenFunction &CGF,
2634 ReturnValueSlot Return,
2635 QualType ResultType,
2636 Selector Sel,
2637 llvm::Value *Receiver,
2638 const CallArgList &CallArgs,
2639 const ObjCInterfaceDecl *Class,
2640 const ObjCMethodDecl *Method) {
2641 CGBuilderTy &Builder = CGF.Builder;
2642
2643 // Strip out message sends to retain / release in GC mode
2644 if (CGM.getLangOpts().getGC() == LangOptions::GCOnly) {
2645 if (Sel == RetainSel || Sel == AutoreleaseSel) {
2646 return RValue::get(EnforceType(Builder, Receiver,
2647 CGM.getTypes().ConvertType(ResultType)));
2648 }
2649 if (Sel == ReleaseSel) {
2650 return RValue::get(nullptr);
2651 }
2652 }
2653
2654 // If the return type is something that goes in an integer register, the
2655 // runtime will handle 0 returns. For other cases, we fill in the 0 value
2656 // ourselves.
2657 //
2658 // The language spec says the result of this kind of message send is
2659 // undefined, but lots of people seem to have forgotten to read that
2660 // paragraph and insist on sending messages to nil that have structure
2661 // returns. With GCC, this generates a random return value (whatever happens
2662 // to be on the stack / in those registers at the time) on most platforms,
2663 // and generates an illegal instruction trap on SPARC. With LLVM it corrupts
2664 // the stack.
2665 bool isPointerSizedReturn = (ResultType->isAnyPointerType() ||
2666 ResultType->isIntegralOrEnumerationType() || ResultType->isVoidType());
2667
2668 llvm::BasicBlock *startBB = nullptr;
2669 llvm::BasicBlock *messageBB = nullptr;
2670 llvm::BasicBlock *continueBB = nullptr;
2671
2672 if (!isPointerSizedReturn) {
2673 startBB = Builder.GetInsertBlock();
2674 messageBB = CGF.createBasicBlock("msgSend");
2675 continueBB = CGF.createBasicBlock("continue");
2676
2677 llvm::Value *isNil = Builder.CreateICmpEQ(Receiver,
2678 llvm::Constant::getNullValue(Receiver->getType()));
2679 Builder.CreateCondBr(isNil, continueBB, messageBB);
2680 CGF.EmitBlock(messageBB);
2681 }
2682
2683 IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy));
2684 llvm::Value *cmd;
2685 if (Method)
2686 cmd = GetSelector(CGF, Method);
2687 else
2688 cmd = GetSelector(CGF, Sel);
2689 cmd = EnforceType(Builder, cmd, SelectorTy);
2690 Receiver = EnforceType(Builder, Receiver, IdTy);
2691
2692 llvm::Metadata *impMD[] = {
2693 llvm::MDString::get(VMContext, Sel.getAsString()),
2694 llvm::MDString::get(VMContext, Class ? Class->getNameAsString() : ""),
2695 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
2696 llvm::Type::getInt1Ty(VMContext), Class != nullptr))};
2697 llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD);
2698
2699 CallArgList ActualArgs;
2700 ActualArgs.add(RValue::get(Receiver), ASTIdTy);
2701 ActualArgs.add(RValue::get(cmd), CGF.getContext().getObjCSelType());
2702 ActualArgs.addFrom(CallArgs);
2703
2704 MessageSendInfo MSI = getMessageSendInfo(Method, ResultType, ActualArgs);
2705
2706 // Get the IMP to call
2707 llvm::Value *imp;
2708
2709 // If we have non-legacy dispatch specified, we try using the objc_msgSend()
2710 // functions. These are not supported on all platforms (or all runtimes on a
2711 // given platform), so we
2712 switch (CGM.getCodeGenOpts().getObjCDispatchMethod()) {
2713 case CodeGenOptions::Legacy:
2714 imp = LookupIMP(CGF, Receiver, cmd, node, MSI);
2715 break;
2716 case CodeGenOptions::Mixed:
2717 case CodeGenOptions::NonLegacy:
2718 if (CGM.ReturnTypeUsesFPRet(ResultType)) {
2719 imp =
2720 CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, IdTy, true),
2721 "objc_msgSend_fpret")
2722 .getCallee();
2723 } else if (CGM.ReturnTypeUsesSRet(MSI.CallInfo)) {
2724 // The actual types here don't matter - we're going to bitcast the
2725 // function anyway
2726 imp =
2727 CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, IdTy, true),
2728 "objc_msgSend_stret")
2729 .getCallee();
2730 } else {
2731 imp = CGM.CreateRuntimeFunction(
2732 llvm::FunctionType::get(IdTy, IdTy, true), "objc_msgSend")
2733 .getCallee();
2734 }
2735 }
2736
2737 // Reset the receiver in case the lookup modified it
2738 ActualArgs[0] = CallArg(RValue::get(Receiver), ASTIdTy);
2739
2740 imp = EnforceType(Builder, imp, MSI.MessengerType);
2741
2742 llvm::CallBase *call;
2743 CGCallee callee(CGCalleeInfo(), imp);
2744 RValue msgRet = CGF.EmitCall(MSI.CallInfo, callee, Return, ActualArgs, &call);
2745 call->setMetadata(msgSendMDKind, node);
2746
2747
2748 if (!isPointerSizedReturn) {
2749 messageBB = CGF.Builder.GetInsertBlock();
2750 CGF.Builder.CreateBr(continueBB);
2751 CGF.EmitBlock(continueBB);
2752 if (msgRet.isScalar()) {
2753 llvm::Value *v = msgRet.getScalarVal();
2754 llvm::PHINode *phi = Builder.CreatePHI(v->getType(), 2);
2755 phi->addIncoming(v, messageBB);
2756 phi->addIncoming(llvm::Constant::getNullValue(v->getType()), startBB);
2757 msgRet = RValue::get(phi);
2758 } else if (msgRet.isAggregate()) {
2759 Address v = msgRet.getAggregateAddress();
2760 llvm::PHINode *phi = Builder.CreatePHI(v.getType(), 2);
2761 llvm::Type *RetTy = v.getElementType();
2762 Address NullVal = CGF.CreateTempAlloca(RetTy, v.getAlignment(), "null");
2763 CGF.InitTempAlloca(NullVal, llvm::Constant::getNullValue(RetTy));
2764 phi->addIncoming(v.getPointer(), messageBB);
2765 phi->addIncoming(NullVal.getPointer(), startBB);
2766 msgRet = RValue::getAggregate(Address(phi, v.getAlignment()));
2767 } else /* isComplex() */ {
2768 std::pair<llvm::Value*,llvm::Value*> v = msgRet.getComplexVal();
2769 llvm::PHINode *phi = Builder.CreatePHI(v.first->getType(), 2);
2770 phi->addIncoming(v.first, messageBB);
2771 phi->addIncoming(llvm::Constant::getNullValue(v.first->getType()),
2772 startBB);
2773 llvm::PHINode *phi2 = Builder.CreatePHI(v.second->getType(), 2);
2774 phi2->addIncoming(v.second, messageBB);
2775 phi2->addIncoming(llvm::Constant::getNullValue(v.second->getType()),
2776 startBB);
2777 msgRet = RValue::getComplex(phi, phi2);
2778 }
2779 }
2780 return msgRet;
2781}
2782
2783/// Generates a MethodList. Used in construction of a objc_class and
2784/// objc_category structures.
2785llvm::Constant *CGObjCGNU::
2786GenerateMethodList(StringRef ClassName,
2787 StringRef CategoryName,
2788 ArrayRef<const ObjCMethodDecl*> Methods,
2789 bool isClassMethodList) {
2790 if (Methods.empty())
2791 return NULLPtr;
2792
2793 ConstantInitBuilder Builder(CGM);
2794
2795 auto MethodList = Builder.beginStruct();
2796 MethodList.addNullPointer(CGM.Int8PtrTy);
2797 MethodList.addInt(Int32Ty, Methods.size());
2798
2799 // Get the method structure type.
2800 llvm::StructType *ObjCMethodTy =
2801 llvm::StructType::get(CGM.getLLVMContext(), {
2802 PtrToInt8Ty, // Really a selector, but the runtime creates it us.
2803 PtrToInt8Ty, // Method types
2804 IMPTy // Method pointer
2805 });
2806 bool isV2ABI = isRuntime(ObjCRuntime::GNUstep, 2);
2807 if (isV2ABI) {
2808 // size_t size;
2809 llvm::DataLayout td(&TheModule);
2810 MethodList.addInt(SizeTy, td.getTypeSizeInBits(ObjCMethodTy) /
2811 CGM.getContext().getCharWidth());
2812 ObjCMethodTy =
2813 llvm::StructType::get(CGM.getLLVMContext(), {
2814 IMPTy, // Method pointer
2815 PtrToInt8Ty, // Selector
2816 PtrToInt8Ty // Extended type encoding
2817 });
2818 } else {
2819 ObjCMethodTy =
2820 llvm::StructType::get(CGM.getLLVMContext(), {
2821 PtrToInt8Ty, // Really a selector, but the runtime creates it us.
2822 PtrToInt8Ty, // Method types
2823 IMPTy // Method pointer
2824 });
2825 }
2826 auto MethodArray = MethodList.beginArray();
2827 ASTContext &Context = CGM.getContext();
2828 for (const auto *OMD : Methods) {
2829 llvm::Constant *FnPtr =
2830 TheModule.getFunction(getSymbolNameForMethod(OMD));
2831 assert(FnPtr && "Can't generate metadata for method that doesn't exist")(static_cast<void> (0));
2832 auto Method = MethodArray.beginStruct(ObjCMethodTy);
2833 if (isV2ABI) {
2834 Method.addBitCast(FnPtr, IMPTy);
2835 Method.add(GetConstantSelector(OMD->getSelector(),
2836 Context.getObjCEncodingForMethodDecl(OMD)));
2837 Method.add(MakeConstantString(Context.getObjCEncodingForMethodDecl(OMD, true)));
2838 } else {
2839 Method.add(MakeConstantString(OMD->getSelector().getAsString()));
2840 Method.add(MakeConstantString(Context.getObjCEncodingForMethodDecl(OMD)));
2841 Method.addBitCast(FnPtr, IMPTy);
2842 }
2843 Method.finishAndAddTo(MethodArray);
2844 }
2845 MethodArray.finishAndAddTo(MethodList);
2846
2847 // Create an instance of the structure
2848 return MethodList.finishAndCreateGlobal(".objc_method_list",
2849 CGM.getPointerAlign());
2850}
2851
2852/// Generates an IvarList. Used in construction of a objc_class.
2853llvm::Constant *CGObjCGNU::
2854GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames,
2855 ArrayRef<llvm::Constant *> IvarTypes,
2856 ArrayRef<llvm::Constant *> IvarOffsets,
2857 ArrayRef<llvm::Constant *> IvarAlign,
2858 ArrayRef<Qualifiers::ObjCLifetime> IvarOwnership) {
2859 if (IvarNames.empty())
2860 return NULLPtr;
2861
2862 ConstantInitBuilder Builder(CGM);
2863
2864 // Structure containing array count followed by array.
2865 auto IvarList = Builder.beginStruct();
2866 IvarList.addInt(IntTy, (int)IvarNames.size());
2867
2868 // Get the ivar structure type.
2869 llvm::StructType *ObjCIvarTy =
2870 llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty, IntTy);
2871
2872 // Array of ivar structures.
2873 auto Ivars = IvarList.beginArray(ObjCIvarTy);
2874 for (unsigned int i = 0, e = IvarNames.size() ; i < e ; i++) {
2875 auto Ivar = Ivars.beginStruct(ObjCIvarTy);
2876 Ivar.add(IvarNames[i]);
2877 Ivar.add(IvarTypes[i]);
2878 Ivar.add(IvarOffsets[i]);
2879 Ivar.finishAndAddTo(Ivars);
2880 }
2881 Ivars.finishAndAddTo(IvarList);
2882
2883 // Create an instance of the structure
2884 return IvarList.finishAndCreateGlobal(".objc_ivar_list",
2885 CGM.getPointerAlign());
2886}
2887
2888/// Generate a class structure
2889llvm::Constant *CGObjCGNU::GenerateClassStructure(
2890 llvm::Constant *MetaClass,
2891 llvm::Constant *SuperClass,
2892 unsigned info,
2893 const char *Name,
2894 llvm::Constant *Version,
2895 llvm::Constant *InstanceSize,
2896 llvm::Constant *IVars,
2897 llvm::Constant *Methods,
2898 llvm::Constant *Protocols,
2899 llvm::Constant *IvarOffsets,
2900 llvm::Constant *Properties,
2901 llvm::Constant *StrongIvarBitmap,
2902 llvm::Constant *WeakIvarBitmap,
2903 bool isMeta) {
2904 // Set up the class structure
2905 // Note: Several of these are char*s when they should be ids. This is
2906 // because the runtime performs this translation on load.
2907 //
2908 // Fields marked New ABI are part of the GNUstep runtime. We emit them
2909 // anyway; the classes will still work with the GNU runtime, they will just
2910 // be ignored.
2911 llvm::StructType *ClassTy = llvm::StructType::get(
2912 PtrToInt8Ty, // isa
2913 PtrToInt8Ty, // super_class
2914 PtrToInt8Ty, // name
2915 LongTy, // version
2916 LongTy, // info
2917 LongTy, // instance_size
2918 IVars->getType(), // ivars
2919 Methods->getType(), // methods
2920 // These are all filled in by the runtime, so we pretend
2921 PtrTy, // dtable
2922 PtrTy, // subclass_list
2923 PtrTy, // sibling_class
2924 PtrTy, // protocols
2925 PtrTy, // gc_object_type
2926 // New ABI:
2927 LongTy, // abi_version
2928 IvarOffsets->getType(), // ivar_offsets
2929 Properties->getType(), // properties
2930 IntPtrTy, // strong_pointers
2931 IntPtrTy // weak_pointers
2932 );
2933
2934 ConstantInitBuilder Builder(CGM);
2935 auto Elements = Builder.beginStruct(ClassTy);
2936
2937 // Fill in the structure
2938
2939 // isa
2940 Elements.addBitCast(MetaClass, PtrToInt8Ty);
2941 // super_class
2942 Elements.add(SuperClass);
2943 // name
2944 Elements.add(MakeConstantString(Name, ".class_name"));
2945 // version
2946 Elements.addInt(LongTy, 0);
2947 // info
2948 Elements.addInt(LongTy, info);
2949 // instance_size
2950 if (isMeta) {
2951 llvm::DataLayout td(&TheModule);
2952 Elements.addInt(LongTy,
2953 td.getTypeSizeInBits(ClassTy) /
2954 CGM.getContext().getCharWidth());
2955 } else
2956 Elements.add(InstanceSize);
2957 // ivars
2958 Elements.add(IVars);
2959 // methods
2960 Elements.add(Methods);
2961 // These are all filled in by the runtime, so we pretend
2962 // dtable
2963 Elements.add(NULLPtr);
2964 // subclass_list
2965 Elements.add(NULLPtr);
2966 // sibling_class
2967 Elements.add(NULLPtr);
2968 // protocols
2969 Elements.addBitCast(Protocols, PtrTy);
2970 // gc_object_type
2971 Elements.add(NULLPtr);
2972 // abi_version
2973 Elements.addInt(LongTy, ClassABIVersion);
2974 // ivar_offsets
2975 Elements.add(IvarOffsets);
2976 // properties
2977 Elements.add(Properties);
2978 // strong_pointers
2979 Elements.add(StrongIvarBitmap);
2980 // weak_pointers
2981 Elements.add(WeakIvarBitmap);
2982 // Create an instance of the structure
2983 // This is now an externally visible symbol, so that we can speed up class
2984 // messages in the next ABI. We may already have some weak references to
2985 // this, so check and fix them properly.
2986 std::string ClassSym((isMeta ? "_OBJC_METACLASS_": "_OBJC_CLASS_") +
2987 std::string(Name));
2988 llvm::GlobalVariable *ClassRef = TheModule.getNamedGlobal(ClassSym);
2989 llvm::Constant *Class =
2990 Elements.finishAndCreateGlobal(ClassSym, CGM.getPointerAlign(), false,
2991 llvm::GlobalValue::ExternalLinkage);
2992 if (ClassRef) {
2993 ClassRef->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(Class,
2994 ClassRef->getType()));
2995 ClassRef->removeFromParent();
2996 Class->setName(ClassSym);
2997 }
2998 return Class;
2999}
3000
3001llvm::Constant *CGObjCGNU::
3002GenerateProtocolMethodList(ArrayRef<const ObjCMethodDecl*> Methods) {
3003 // Get the method structure type.
3004 llvm::StructType *ObjCMethodDescTy =
3005 llvm::StructType::get(CGM.getLLVMContext(), { PtrToInt8Ty, PtrToInt8Ty });
3006 ASTContext &Context = CGM.getContext();
3007 ConstantInitBuilder Builder(CGM);
3008 auto MethodList = Builder.beginStruct();
3009 MethodList.addInt(IntTy, Methods.size());
3010 auto MethodArray = MethodList.beginArray(ObjCMethodDescTy);
3011 for (auto *M : Methods) {
3012 auto Method = MethodArray.beginStruct(ObjCMethodDescTy);
3013 Method.add(MakeConstantString(M->getSelector().getAsString()));
3014 Method.add(MakeConstantString(Context.getObjCEncodingForMethodDecl(M)));
3015 Method.finishAndAddTo(MethodArray);
3016 }
3017 MethodArray.finishAndAddTo(MethodList);
3018 return MethodList.finishAndCreateGlobal(".objc_method_list",
3019 CGM.getPointerAlign());
3020}
3021
3022// Create the protocol list structure used in classes, categories and so on
3023llvm::Constant *
3024CGObjCGNU::GenerateProtocolList(ArrayRef<std::string> Protocols) {
3025
3026 ConstantInitBuilder Builder(CGM);
3027 auto ProtocolList = Builder.beginStruct();
3028 ProtocolList.add(NULLPtr);
3029 ProtocolList.addInt(LongTy, Protocols.size());
3030
3031 auto Elements = ProtocolList.beginArray(PtrToInt8Ty);
3032 for (const std::string *iter = Protocols.begin(), *endIter = Protocols.end();
3033 iter != endIter ; iter++) {
3034 llvm::Constant *protocol = nullptr;
3035 llvm::StringMap<llvm::Constant*>::iterator value =
3036 ExistingProtocols.find(*iter);
3037 if (value == ExistingProtocols.end()) {
3038 protocol = GenerateEmptyProtocol(*iter);
3039 } else {
3040 protocol = value->getValue();
3041 }
3042 Elements.addBitCast(protocol, PtrToInt8Ty);
3043 }
3044 Elements.finishAndAddTo(ProtocolList);
3045 return ProtocolList.finishAndCreateGlobal(".objc_protocol_list",
3046 CGM.getPointerAlign());
3047}
3048
3049llvm::Value *CGObjCGNU::GenerateProtocolRef(CodeGenFunction &CGF,
3050 const ObjCProtocolDecl *PD) {
3051 auto protocol = GenerateProtocolRef(PD);
3052 llvm::Type *T =
3053 CGM.getTypes().ConvertType(CGM.getContext().getObjCProtoType());
3054 return CGF.Builder.CreateBitCast(protocol, llvm::PointerType::getUnqual(T));
3055}
3056
3057llvm::Constant *CGObjCGNU::GenerateProtocolRef(const ObjCProtocolDecl *PD) {
3058 llvm::Constant *&protocol = ExistingProtocols[PD->getNameAsString()];
3059 if (!protocol)
3060 GenerateProtocol(PD);
3061 assert(protocol && "Unknown protocol")(static_cast<void> (0));
3062 return protocol;
3063}
3064
3065llvm::Constant *
3066CGObjCGNU::GenerateEmptyProtocol(StringRef ProtocolName) {
3067 llvm::Constant *ProtocolList = GenerateProtocolList({});
3068 llvm::Constant *MethodList = GenerateProtocolMethodList({});
3069 MethodList = llvm::ConstantExpr::getBitCast(MethodList, PtrToInt8Ty);
3070 // Protocols are objects containing lists of the methods implemented and
3071 // protocols adopted.
3072 ConstantInitBuilder Builder(CGM);
3073 auto Elements = Builder.beginStruct();
3074
3075 // The isa pointer must be set to a magic number so the runtime knows it's
3076 // the correct layout.
3077 Elements.add(llvm::ConstantExpr::getIntToPtr(
3078 llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy));
3079
3080 Elements.add(MakeConstantString(ProtocolName, ".objc_protocol_name"));
3081 Elements.add(ProtocolList); /* .protocol_list */
3082 Elements.add(MethodList); /* .instance_methods */
3083 Elements.add(MethodList); /* .class_methods */
3084 Elements.add(MethodList); /* .optional_instance_methods */
3085 Elements.add(MethodList); /* .optional_class_methods */
3086 Elements.add(NULLPtr); /* .properties */
3087 Elements.add(NULLPtr); /* .optional_properties */
3088 return Elements.finishAndCreateGlobal(SymbolForProtocol(ProtocolName),
3089 CGM.getPointerAlign());
3090}
3091
3092void CGObjCGNU::GenerateProtocol(const ObjCProtocolDecl *PD) {
3093 if (PD->isNonRuntimeProtocol())
3094 return;
3095
3096 std::string ProtocolName = PD->getNameAsString();
3097
3098 // Use the protocol definition, if there is one.
3099 if (const ObjCProtocolDecl *Def = PD->getDefinition())
3100 PD = Def;
3101
3102 SmallVector<std::string, 16> Protocols;
3103 for (const auto *PI : PD->protocols())
3104 Protocols.push_back(PI->getNameAsString());
3105 SmallVector<const ObjCMethodDecl*, 16> InstanceMethods;
3106 SmallVector<const ObjCMethodDecl*, 16> OptionalInstanceMethods;
3107 for (const auto *I : PD->instance_methods())
3108 if (I->isOptional())
3109 OptionalInstanceMethods.push_back(I);
3110 else
3111 InstanceMethods.push_back(I);
3112 // Collect information about class methods:
3113 SmallVector<const ObjCMethodDecl*, 16> ClassMethods;
3114 SmallVector<const ObjCMethodDecl*, 16> OptionalClassMethods;
3115 for (const auto *I : PD->class_methods())
3116 if (I->isOptional())
3117 OptionalClassMethods.push_back(I);
3118 else
3119 ClassMethods.push_back(I);
3120
3121 llvm::Constant *ProtocolList = GenerateProtocolList(Protocols);
3122 llvm::Constant *InstanceMethodList =
3123 GenerateProtocolMethodList(InstanceMethods);
3124 llvm::Constant *ClassMethodList =
3125 GenerateProtocolMethodList(ClassMethods);
3126 llvm::Constant *OptionalInstanceMethodList =
3127 GenerateProtocolMethodList(OptionalInstanceMethods);
3128 llvm::Constant *OptionalClassMethodList =
3129 GenerateProtocolMethodList(OptionalClassMethods);
3130
3131 // Property metadata: name, attributes, isSynthesized, setter name, setter
3132 // types, getter name, getter types.
3133 // The isSynthesized value is always set to 0 in a protocol. It exists to
3134 // simplify the runtime library by allowing it to use the same data
3135 // structures for protocol metadata everywhere.
3136
3137 llvm::Constant *PropertyList =
3138 GeneratePropertyList(nullptr, PD, false, false);
3139 llvm::Constant *OptionalPropertyList =
3140 GeneratePropertyList(nullptr, PD, false, true);
3141
3142 // Protocols are objects containing lists of the methods implemented and
3143 // protocols adopted.
3144 // The isa pointer must be set to a magic number so the runtime knows it's
3145 // the correct layout.
3146 ConstantInitBuilder Builder(CGM);
3147 auto Elements = Builder.beginStruct();
3148 Elements.add(
3149 llvm::ConstantExpr::getIntToPtr(
3150 llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy));
3151 Elements.add(MakeConstantString(ProtocolName));
3152 Elements.add(ProtocolList);
3153 Elements.add(InstanceMethodList);
3154 Elements.add(ClassMethodList);
3155 Elements.add(OptionalInstanceMethodList);
3156 Elements.add(OptionalClassMethodList);
3157 Elements.add(PropertyList);
3158 Elements.add(OptionalPropertyList);
3159 ExistingProtocols[ProtocolName] =
3160 llvm::ConstantExpr::getBitCast(
3161 Elements.finishAndCreateGlobal(".objc_protocol", CGM.getPointerAlign()),
3162 IdTy);
3163}
3164void CGObjCGNU::GenerateProtocolHolderCategory() {
3165 // Collect information about instance methods
3166
3167 ConstantInitBuilder Builder(CGM);
3168 auto Elements = Builder.beginStruct();
3169
3170 const std::string ClassName = "__ObjC_Protocol_Holder_Ugly_Hack";
3171 const std::string CategoryName = "AnotherHack";
3172 Elements.add(MakeConstantString(CategoryName));
3173 Elements.add(MakeConstantString(ClassName));
3174 // Instance method list
3175 Elements.addBitCast(GenerateMethodList(
3176 ClassName, CategoryName, {}, false), PtrTy);
3177 // Class method list
3178 Elements.addBitCast(GenerateMethodList(
3179 ClassName, CategoryName, {}, true), PtrTy);
3180
3181 // Protocol list
3182 ConstantInitBuilder ProtocolListBuilder(CGM);
3183 auto ProtocolList = ProtocolListBuilder.beginStruct();
3184 ProtocolList.add(NULLPtr);
3185 ProtocolList.addInt(LongTy, ExistingProtocols.size());
3186 auto ProtocolElements = ProtocolList.beginArray(PtrTy);
3187 for (auto iter = ExistingProtocols.begin(), endIter = ExistingProtocols.end();
3188 iter != endIter ; iter++) {
3189 ProtocolElements.addBitCast(iter->getValue(), PtrTy);
3190 }
3191 ProtocolElements.finishAndAddTo(ProtocolList);
3192 Elements.addBitCast(
3193 ProtocolList.finishAndCreateGlobal(".objc_protocol_list",
3194 CGM.getPointerAlign()),
3195 PtrTy);
3196 Categories.push_back(llvm::ConstantExpr::getBitCast(
3197 Elements.finishAndCreateGlobal("", CGM.getPointerAlign()),
3198 PtrTy));
3199}
3200
3201/// Libobjc2 uses a bitfield representation where small(ish) bitfields are
3202/// stored in a 64-bit value with the low bit set to 1 and the remaining 63
3203/// bits set to their values, LSB first, while larger ones are stored in a
3204/// structure of this / form:
3205///
3206/// struct { int32_t length; int32_t values[length]; };
3207///
3208/// The values in the array are stored in host-endian format, with the least
3209/// significant bit being assumed to come first in the bitfield. Therefore, a
3210/// bitfield with the 64th bit set will be (int64_t)&{ 2, [0, 1<<31] }, while a
3211/// bitfield / with the 63rd bit set will be 1<<64.
3212llvm::Constant *CGObjCGNU::MakeBitField(ArrayRef<bool> bits) {
3213 int bitCount = bits.size();
3214 int ptrBits = CGM.getDataLayout().getPointerSizeInBits();
3215 if (bitCount < ptrBits) {
3216 uint64_t val = 1;
3217 for (int i=0 ; i<bitCount ; ++i) {
3218 if (bits[i]) val |= 1ULL<<(i+1);
3219 }
3220 return llvm::ConstantInt::get(IntPtrTy, val);
3221 }
3222 SmallVector<llvm::Constant *, 8> values;
3223 int v=0;
3224 while (v < bitCount) {
3225 int32_t word = 0;
3226 for (int i=0 ; (i<32) && (v<bitCount) ; ++i) {
3227 if (bits[v]) word |= 1<<i;
3228 v++;
3229 }
3230 values.push_back(llvm::ConstantInt::get(Int32Ty, word));
3231 }
3232
3233 ConstantInitBuilder builder(CGM);
3234 auto fields = builder.beginStruct();
3235 fields.addInt(Int32Ty, values.size());
3236 auto array = fields.beginArray();
3237 for (auto v : values) array.add(v);
3238 array.finishAndAddTo(fields);
3239
3240 llvm::Constant *GS =
3241 fields.finishAndCreateGlobal("", CharUnits::fromQuantity(4));
3242 llvm::Constant *ptr = llvm::ConstantExpr::getPtrToInt(GS, IntPtrTy);
3243 return ptr;
3244}
3245
3246llvm::Constant *CGObjCGNU::GenerateCategoryProtocolList(const
3247 ObjCCategoryDecl *OCD) {
3248 const auto &RefPro = OCD->getReferencedProtocols();
3249 const auto RuntimeProtos =
3250 GetRuntimeProtocolList(RefPro.begin(), RefPro.end());
3251 SmallVector<std::string, 16> Protocols;
3252 for (const auto *PD : RuntimeProtos)
3253 Protocols.push_back(PD->getNameAsString());
3254 return GenerateProtocolList(Protocols);
3255}
3256
3257void CGObjCGNU::GenerateCategory(const ObjCCategoryImplDecl *OCD) {
3258 const ObjCInterfaceDecl *Class = OCD->getClassInterface();
3259 std::string ClassName = Class->getNameAsString();
3260 std::string CategoryName = OCD->getNameAsString();
3261
3262 // Collect the names of referenced protocols
3263 const ObjCCategoryDecl *CatDecl = OCD->getCategoryDecl();
3264
3265 ConstantInitBuilder Builder(CGM);
3266 auto Elements = Builder.beginStruct();
3267 Elements.add(MakeConstantString(CategoryName));
3268 Elements.add(MakeConstantString(ClassName));
3269 // Instance method list
3270 SmallVector<ObjCMethodDecl*, 16> InstanceMethods;
3271 InstanceMethods.insert(InstanceMethods.begin(), OCD->instmeth_begin(),
3272 OCD->instmeth_end());
3273 Elements.addBitCast(
3274 GenerateMethodList(ClassName, CategoryName, InstanceMethods, false),
3275 PtrTy);
3276 // Class method list
3277
3278 SmallVector<ObjCMethodDecl*, 16> ClassMethods;
3279 ClassMethods.insert(ClassMethods.begin(), OCD->classmeth_begin(),
3280 OCD->classmeth_end());
3281 Elements.addBitCast(
3282 GenerateMethodList(ClassName, CategoryName, ClassMethods, true),
3283 PtrTy);
3284 // Protocol list
3285 Elements.addBitCast(GenerateCategoryProtocolList(CatDecl), PtrTy);
3286 if (isRuntime(ObjCRuntime::GNUstep, 2)) {
3287 const ObjCCategoryDecl *Category =
3288 Class->FindCategoryDeclaration(OCD->getIdentifier());
3289 if (Category) {
3290 // Instance properties
3291 Elements.addBitCast(GeneratePropertyList(OCD, Category, false), PtrTy);
3292 // Class properties
3293 Elements.addBitCast(GeneratePropertyList(OCD, Category, true), PtrTy);
3294 } else {
3295 Elements.addNullPointer(PtrTy);
3296 Elements.addNullPointer(PtrTy);
3297 }
3298 }
3299
3300 Categories.push_back(llvm::ConstantExpr::getBitCast(
3301 Elements.finishAndCreateGlobal(
3302 std::string(".objc_category_")+ClassName+CategoryName,
3303 CGM.getPointerAlign()),
3304 PtrTy));
3305}
3306
3307llvm::Constant *CGObjCGNU::GeneratePropertyList(const Decl *Container,
3308 const ObjCContainerDecl *OCD,
3309 bool isClassProperty,
3310 bool protocolOptionalProperties) {
3311
3312 SmallVector<const ObjCPropertyDecl *, 16> Properties;
3313 llvm::SmallPtrSet<const IdentifierInfo*, 16> PropertySet;
3314 bool isProtocol = isa<ObjCProtocolDecl>(OCD);
3315 ASTContext &Context = CGM.getContext();
3316
3317 std::function<void(const ObjCProtocolDecl *Proto)> collectProtocolProperties
3318 = [&](const ObjCProtocolDecl *Proto) {
3319 for (const auto *P : Proto->protocols())
3320 collectProtocolProperties(P);
3321 for (const auto *PD : Proto->properties()) {
3322 if (isClassProperty != PD->isClassProperty())
3323 continue;
3324 // Skip any properties that are declared in protocols that this class
3325 // conforms to but are not actually implemented by this class.
3326 if (!isProtocol && !Context.getObjCPropertyImplDeclForPropertyDecl(PD, Container))
3327 continue;
3328 if (!PropertySet.insert(PD->getIdentifier()).second)
3329 continue;
3330 Properties.push_back(PD);
3331 }
3332 };
3333
3334 if (const ObjCInterfaceDecl *OID = dyn_cast<ObjCInterfaceDecl>(OCD))
3335 for (const ObjCCategoryDecl *ClassExt : OID->known_extensions())
3336 for (auto *PD : ClassExt->properties()) {
3337 if (isClassProperty != PD->isClassProperty())
3338 continue;
3339 PropertySet.insert(PD->getIdentifier());
3340 Properties.push_back(PD);
3341 }
3342
3343 for (const auto *PD : OCD->properties()) {
3344 if (isClassProperty != PD->isClassProperty())
3345 continue;
3346 // If we're generating a list for a protocol, skip optional / required ones
3347 // when generating the other list.
3348 if (isProtocol && (protocolOptionalProperties != PD->isOptional()))
3349 continue;
3350 // Don't emit duplicate metadata for properties that were already in a
3351 // class extension.
3352 if (!PropertySet.insert(PD->getIdentifier()).second)
3353 continue;
3354
3355 Properties.push_back(PD);
3356 }
3357
3358 if (const ObjCInterfaceDecl *OID = dyn_cast<ObjCInterfaceDecl>(OCD))
3359 for (const auto *P : OID->all_referenced_protocols())
3360 collectProtocolProperties(P);
3361 else if (const ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(OCD))
3362 for (const auto *P : CD->protocols())
3363 collectProtocolProperties(P);
3364
3365 auto numProperties = Properties.size();
3366
3367 if (numProperties == 0)
3368 return NULLPtr;
3369
3370 ConstantInitBuilder builder(CGM);
3371 auto propertyList = builder.beginStruct();
3372 auto properties = PushPropertyListHeader(propertyList, numProperties);
3373
3374 // Add all of the property methods need adding to the method list and to the
3375 // property metadata list.
3376 for (auto *property : Properties) {
3377 bool isSynthesized = false;
3378 bool isDynamic = false;
3379 if (!isProtocol) {
3380 auto *propertyImpl = Context.getObjCPropertyImplDeclForPropertyDecl(property, Container);
3381 if (propertyImpl) {
3382 isSynthesized = (propertyImpl->getPropertyImplementation() ==
3383 ObjCPropertyImplDecl::Synthesize);
3384 isDynamic = (propertyImpl->getPropertyImplementation() ==
3385 ObjCPropertyImplDecl::Dynamic);
3386 }
3387 }
3388 PushProperty(properties, property, Container, isSynthesized, isDynamic);
3389 }
3390 properties.finishAndAddTo(propertyList);
3391
3392 return propertyList.finishAndCreateGlobal(".objc_property_list",
3393 CGM.getPointerAlign());
3394}
3395
3396void CGObjCGNU::RegisterAlias(const ObjCCompatibleAliasDecl *OAD) {
3397 // Get the class declaration for which the alias is specified.
3398 ObjCInterfaceDecl *ClassDecl =
3399 const_cast<ObjCInterfaceDecl *>(OAD->getClassInterface());
3400 ClassAliases.emplace_back(ClassDecl->getNameAsString(),
3401 OAD->getNameAsString());
3402}
3403
3404void CGObjCGNU::GenerateClass(const ObjCImplementationDecl *OID) {
3405 ASTContext &Context = CGM.getContext();
3406
3407 // Get the superclass name.
3408 const ObjCInterfaceDecl * SuperClassDecl =
3409 OID->getClassInterface()->getSuperClass();
3410 std::string SuperClassName;
3411 if (SuperClassDecl) {
3412 SuperClassName = SuperClassDecl->getNameAsString();
3413 EmitClassRef(SuperClassName);
3414 }
3415
3416 // Get the class name
3417 ObjCInterfaceDecl *ClassDecl =
3418 const_cast<ObjCInterfaceDecl *>(OID->getClassInterface());
3419 std::string ClassName = ClassDecl->getNameAsString();
3420
3421 // Emit the symbol that is used to generate linker errors if this class is
3422 // referenced in other modules but not declared.
3423 std::string classSymbolName = "__objc_class_name_" + ClassName;
3424 if (auto *symbol = TheModule.getGlobalVariable(classSymbolName)) {
3425 symbol->setInitializer(llvm::ConstantInt::get(LongTy, 0));
3426 } else {
3427 new llvm::GlobalVariable(TheModule, LongTy, false,
3428 llvm::GlobalValue::ExternalLinkage,
3429 llvm::ConstantInt::get(LongTy, 0),
3430 classSymbolName);
3431 }
3432
3433 // Get the size of instances.
3434 int instanceSize =
3435 Context.getASTObjCImplementationLayout(OID).getSize().getQuantity();
3436
3437 // Collect information about instance variables.
3438 SmallVector<llvm::Constant*, 16> IvarNames;
3439 SmallVector<llvm::Constant*, 16> IvarTypes;
3440 SmallVector<llvm::Constant*, 16> IvarOffsets;
3441 SmallVector<llvm::Constant*, 16> IvarAligns;
3442 SmallVector<Qualifiers::ObjCLifetime, 16> IvarOwnership;
3443
3444 ConstantInitBuilder IvarOffsetBuilder(CGM);
3445 auto IvarOffsetValues = IvarOffsetBuilder.beginArray(PtrToIntTy);
3446 SmallVector<bool, 16> WeakIvars;
3447 SmallVector<bool, 16> StrongIvars;
3448
3449 int superInstanceSize = !SuperClassDecl ? 0 :
3450 Context.getASTObjCInterfaceLayout(SuperClassDecl).getSize().getQuantity();
3451 // For non-fragile ivars, set the instance size to 0 - {the size of just this
3452 // class}. The runtime will then set this to the correct value on load.
3453 if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
3454 instanceSize = 0 - (instanceSize - superInstanceSize);
3455 }
3456
3457 for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD;
3458 IVD = IVD->getNextIvar()) {
3459 // Store the name
3460 IvarNames.push_back(MakeConstantString(IVD->getNameAsString()));
3461 // Get the type encoding for this ivar
3462 std::string TypeStr;
3463 Context.getObjCEncodingForType(IVD->getType(), TypeStr, IVD);
3464 IvarTypes.push_back(MakeConstantString(TypeStr));
3465 IvarAligns.push_back(llvm::ConstantInt::get(IntTy,
3466 Context.getTypeSize(IVD->getType())));
3467 // Get the offset
3468 uint64_t BaseOffset = ComputeIvarBaseOffset(CGM, OID, IVD);
3469 uint64_t Offset = BaseOffset;
3470 if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
3471 Offset = BaseOffset - superInstanceSize;
3472 }
3473 llvm::Constant *OffsetValue = llvm::ConstantInt::get(IntTy, Offset);
3474 // Create the direct offset value
3475 std::string OffsetName = "__objc_ivar_offset_value_" + ClassName +"." +
3476 IVD->getNameAsString();
3477
3478 llvm::GlobalVariable *OffsetVar = TheModule.getGlobalVariable(OffsetName);
3479 if (OffsetVar) {
3480 OffsetVar->setInitializer(OffsetValue);
3481 // If this is the real definition, change its linkage type so that
3482 // different modules will use this one, rather than their private
3483 // copy.
3484 OffsetVar->setLinkage(llvm::GlobalValue::ExternalLinkage);
3485 } else
3486 OffsetVar = new llvm::GlobalVariable(TheModule, Int32Ty,
3487 false, llvm::GlobalValue::ExternalLinkage,
3488 OffsetValue, OffsetName);
3489 IvarOffsets.push_back(OffsetValue);
3490 IvarOffsetValues.add(OffsetVar);
3491 Qualifiers::ObjCLifetime lt = IVD->getType().getQualifiers().getObjCLifetime();
3492 IvarOwnership.push_back(lt);
3493 switch (lt) {
3494 case Qualifiers::OCL_Strong:
3495 StrongIvars.push_back(true);
3496 WeakIvars.push_back(false);
3497 break;
3498 case Qualifiers::OCL_Weak:
3499 StrongIvars.push_back(false);
3500 WeakIvars.push_back(true);
3501 break;
3502 default:
3503 StrongIvars.push_back(false);
3504 WeakIvars.push_back(false);
3505 }
3506 }
3507 llvm::Constant *StrongIvarBitmap = MakeBitField(StrongIvars);
3508 llvm::Constant *WeakIvarBitmap = MakeBitField(WeakIvars);
3509 llvm::GlobalVariable *IvarOffsetArray =
3510 IvarOffsetValues.finishAndCreateGlobal(".ivar.offsets",
3511 CGM.getPointerAlign());
3512
3513 // Collect information about instance methods
3514 SmallVector<const ObjCMethodDecl*, 16> InstanceMethods;
3515 InstanceMethods.insert(InstanceMethods.begin(), OID->instmeth_begin(),
3516 OID->instmeth_end());
3517
3518 SmallVector<const ObjCMethodDecl*, 16> ClassMethods;
3519 ClassMethods.insert(ClassMethods.begin(), OID->classmeth_begin(),
3520 OID->classmeth_end());
3521
3522 llvm::Constant *Properties = GeneratePropertyList(OID, ClassDecl);
3523
3524 // Collect the names of referenced protocols
3525 auto RefProtocols = ClassDecl->protocols();
3526 auto RuntimeProtocols =
3527 GetRuntimeProtocolList(RefProtocols.begin(), RefProtocols.end());
3528 SmallVector<std::string, 16> Protocols;
3529 for (const auto *I : RuntimeProtocols)
3530 Protocols.push_back(I->getNameAsString());
3531
3532 // Get the superclass pointer.
3533 llvm::Constant *SuperClass;
3534 if (!SuperClassName.empty()) {
3535 SuperClass = MakeConstantString(SuperClassName, ".super_class_name");
3536 } else {
3537 SuperClass = llvm::ConstantPointerNull::get(PtrToInt8Ty);
3538 }
3539 // Empty vector used to construct empty method lists
3540 SmallVector<llvm::Constant*, 1> empty;
3541 // Generate the method and instance variable lists
3542 llvm::Constant *MethodList = GenerateMethodList(ClassName, "",
3543 InstanceMethods, false);
3544 llvm::Constant *ClassMethodList = GenerateMethodList(ClassName, "",
3545 ClassMethods, true);
3546 llvm::Constant *IvarList = GenerateIvarList(IvarNames, IvarTypes,
3547 IvarOffsets, IvarAligns, IvarOwnership);
3548 // Irrespective of whether we are compiling for a fragile or non-fragile ABI,
3549 // we emit a symbol containing the offset for each ivar in the class. This
3550 // allows code compiled for the non-Fragile ABI to inherit from code compiled
3551 // for the legacy ABI, without causing problems. The converse is also
3552 // possible, but causes all ivar accesses to be fragile.
3553
3554 // Offset pointer for getting at the correct field in the ivar list when
3555 // setting up the alias. These are: The base address for the global, the
3556 // ivar array (second field), the ivar in this list (set for each ivar), and
3557 // the offset (third field in ivar structure)
3558 llvm::Type *IndexTy = Int32Ty;
3559 llvm::Constant *offsetPointerIndexes[] = {Zeros[0],
3560 llvm::ConstantInt::get(IndexTy, ClassABIVersion > 1 ? 2 : 1), nullptr,
3561 llvm::ConstantInt::get(IndexTy, ClassABIVersion > 1 ? 3 : 2) };
3562
3563 unsigned ivarIndex = 0;
3564 for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD;
3565 IVD = IVD->getNextIvar()) {
3566 const std::string Name = GetIVarOffsetVariableName(ClassDecl, IVD);
3567 offsetPointerIndexes[2] = llvm::ConstantInt::get(IndexTy, ivarIndex);
3568 // Get the correct ivar field
3569 llvm::Constant *offsetValue = llvm::ConstantExpr::getGetElementPtr(
3570 cast<llvm::GlobalVariable>(IvarList)->getValueType(), IvarList,
3571 offsetPointerIndexes);
3572 // Get the existing variable, if one exists.
3573 llvm::GlobalVariable *offset = TheModule.getNamedGlobal(Name);
3574 if (offset) {
3575 offset->setInitializer(offsetValue);
3576 // If this is the real definition, change its linkage type so that
3577 // different modules will use this one, rather than their private
3578 // copy.
3579 offset->setLinkage(llvm::GlobalValue::ExternalLinkage);
3580 } else
3581 // Add a new alias if there isn't one already.
3582 new llvm::GlobalVariable(TheModule, offsetValue->getType(),
3583 false, llvm::GlobalValue::ExternalLinkage, offsetValue, Name);
3584 ++ivarIndex;
3585 }
3586 llvm::Constant *ZeroPtr = llvm::ConstantInt::get(IntPtrTy, 0);
3587
3588 //Generate metaclass for class methods
3589 llvm::Constant *MetaClassStruct = GenerateClassStructure(
3590 NULLPtr, NULLPtr, 0x12L, ClassName.c_str(), nullptr, Zeros[0],
3591 NULLPtr, ClassMethodList, NULLPtr, NULLPtr,
3592 GeneratePropertyList(OID, ClassDecl, true), ZeroPtr, ZeroPtr, true);
3593 CGM.setGVProperties(cast<llvm::GlobalValue>(MetaClassStruct),
3594 OID->getClassInterface());
3595
3596 // Generate the class structure
3597 llvm::Constant *ClassStruct = GenerateClassStructure(
3598 MetaClassStruct, SuperClass, 0x11L, ClassName.c_str(), nullptr,
3599 llvm::ConstantInt::get(LongTy, instanceSize), IvarList, MethodList,
3600 GenerateProtocolList(Protocols), IvarOffsetArray, Properties,
3601 StrongIvarBitmap, WeakIvarBitmap);
3602 CGM.setGVProperties(cast<llvm::GlobalValue>(ClassStruct),
3603 OID->getClassInterface());
3604
3605 // Resolve the class aliases, if they exist.
3606 if (ClassPtrAlias) {
3607 ClassPtrAlias->replaceAllUsesWith(
3608 llvm::ConstantExpr::getBitCast(ClassStruct, IdTy));
3609 ClassPtrAlias->eraseFromParent();
3610 ClassPtrAlias = nullptr;
3611 }
3612 if (MetaClassPtrAlias) {
3613 MetaClassPtrAlias->replaceAllUsesWith(
3614 llvm::ConstantExpr::getBitCast(MetaClassStruct, IdTy));
3615 MetaClassPtrAlias->eraseFromParent();
3616 MetaClassPtrAlias = nullptr;
3617 }
3618
3619 // Add class structure to list to be added to the symtab later
3620 ClassStruct = llvm::ConstantExpr::getBitCast(ClassStruct, PtrToInt8Ty);
3621 Classes.push_back(ClassStruct);
3622}
3623
3624llvm::Function *CGObjCGNU::ModuleInitFunction() {
3625 // Only emit an ObjC load function if no Objective-C stuff has been called
3626 if (Classes.empty() && Categories.empty() && ConstantStrings.empty() &&
3627 ExistingProtocols.empty() && SelectorTable.empty())
3628 return nullptr;
3629
3630 // Add all referenced protocols to a category.
3631 GenerateProtocolHolderCategory();
3632
3633 llvm::StructType *selStructTy =
3634 dyn_cast<llvm::StructType>(SelectorTy->getElementType());
3635 llvm::Type *selStructPtrTy = SelectorTy;
3636 if (!selStructTy) {
3637 selStructTy = llvm::StructType::get(CGM.getLLVMContext(),
3638 { PtrToInt8Ty, PtrToInt8Ty });
3639 selStructPtrTy = llvm::PointerType::getUnqual(selStructTy);
3640 }
3641
3642 // Generate statics list:
3643 llvm::Constant *statics = NULLPtr;
3644 if (!ConstantStrings.empty()) {
3645 llvm::GlobalVariable *fileStatics = [&] {
3646 ConstantInitBuilder builder(CGM);
3647 auto staticsStruct = builder.beginStruct();
3648
3649 StringRef stringClass = CGM.getLangOpts().ObjCConstantStringClass;
3650 if (stringClass.empty()) stringClass = "NXConstantString";
3651 staticsStruct.add(MakeConstantString(stringClass,
3652 ".objc_static_class_name"));
3653
3654 auto array = staticsStruct.beginArray();
3655 array.addAll(ConstantStrings);
3656 array.add(NULLPtr);
3657 array.finishAndAddTo(staticsStruct);
3658
3659 return staticsStruct.finishAndCreateGlobal(".objc_statics",
3660 CGM.getPointerAlign());
3661 }();
3662
3663 ConstantInitBuilder builder(CGM);
3664 auto allStaticsArray = builder.beginArray(fileStatics->getType());
3665 allStaticsArray.add(fileStatics);
3666 allStaticsArray.addNullPointer(fileStatics->getType());
3667
3668 statics = allStaticsArray.finishAndCreateGlobal(".objc_statics_ptr",
3669 CGM.getPointerAlign());
3670 statics = llvm::ConstantExpr::getBitCast(statics, PtrTy);
3671 }
3672
3673 // Array of classes, categories, and constant objects.
3674
3675 SmallVector<llvm::GlobalAlias*, 16> selectorAliases;
3676 unsigned selectorCount;
3677
3678 // Pointer to an array of selectors used in this module.
3679 llvm::GlobalVariable *selectorList = [&] {
3680 ConstantInitBuilder builder(CGM);
3681 auto selectors = builder.beginArray(selStructTy);
3682 auto &table = SelectorTable; // MSVC workaround
3683 std::vector<Selector> allSelectors;
3684 for (auto &entry : table)
3685 allSelectors.push_back(entry.first);
3686 llvm::sort(allSelectors);
3687
3688 for (auto &untypedSel : allSelectors) {
3689 std::string selNameStr = untypedSel.getAsString();
3690 llvm::Constant *selName = ExportUniqueString(selNameStr, ".objc_sel_name");
3691
3692 for (TypedSelector &sel : table[untypedSel]) {
3693 llvm::Constant *selectorTypeEncoding = NULLPtr;
3694 if (!sel.first.empty())
3695 selectorTypeEncoding =
3696 MakeConstantString(sel.first, ".objc_sel_types");
3697
3698 auto selStruct = selectors.beginStruct(selStructTy);
3699 selStruct.add(selName);
3700 selStruct.add(selectorTypeEncoding);
3701 selStruct.finishAndAddTo(selectors);
3702
3703 // Store the selector alias for later replacement
3704 selectorAliases.push_back(sel.second);
3705 }
3706 }
3707
3708 // Remember the number of entries in the selector table.
3709 selectorCount = selectors.size();
3710
3711 // NULL-terminate the selector list. This should not actually be required,
3712 // because the selector list has a length field. Unfortunately, the GCC
3713 // runtime decides to ignore the length field and expects a NULL terminator,
3714 // and GCC cooperates with this by always setting the length to 0.
3715 auto selStruct = selectors.beginStruct(selStructTy);
3716 selStruct.add(NULLPtr);
3717 selStruct.add(NULLPtr);
3718 selStruct.finishAndAddTo(selectors);
3719
3720 return selectors.finishAndCreateGlobal(".objc_selector_list",
3721 CGM.getPointerAlign());
3722 }();
3723
3724 // Now that all of the static selectors exist, create pointers to them.
3725 for (unsigned i = 0; i < selectorCount; ++i) {
3726 llvm::Constant *idxs[] = {
3727 Zeros[0],
3728 llvm::ConstantInt::get(Int32Ty, i)
3729 };
3730 // FIXME: We're generating redundant loads and stores here!
3731 llvm::Constant *selPtr = llvm::ConstantExpr::getGetElementPtr(
3732 selectorList->getValueType(), selectorList, idxs);
3733 // If selectors are defined as an opaque type, cast the pointer to this
3734 // type.
3735 selPtr = llvm::ConstantExpr::getBitCast(selPtr, SelectorTy);
3736 selectorAliases[i]->replaceAllUsesWith(selPtr);
3737 selectorAliases[i]->eraseFromParent();
3738 }
3739
3740 llvm::GlobalVariable *symtab = [&] {
3741 ConstantInitBuilder builder(CGM);
3742 auto symtab = builder.beginStruct();
3743
3744 // Number of static selectors
3745 symtab.addInt(LongTy, selectorCount);
3746
3747 symtab.addBitCast(selectorList, selStructPtrTy);
3748
3749 // Number of classes defined.
3750 symtab.addInt(CGM.Int16Ty, Classes.size());
3751 // Number of categories defined
3752 symtab.addInt(CGM.Int16Ty, Categories.size());
3753
3754 // Create an array of classes, then categories, then static object instances
3755 auto classList = symtab.beginArray(PtrToInt8Ty);
3756 classList.addAll(Classes);
3757 classList.addAll(Categories);
3758 // NULL-terminated list of static object instances (mainly constant strings)
3759 classList.add(statics);
3760 classList.add(NULLPtr);
3761 classList.finishAndAddTo(symtab);
3762
3763 // Construct the symbol table.
3764 return symtab.finishAndCreateGlobal("", CGM.getPointerAlign());
3765 }();
3766
3767 // The symbol table is contained in a module which has some version-checking
3768 // constants
3769 llvm::Constant *module = [&] {
3770 llvm::Type *moduleEltTys[] = {
3771 LongTy, LongTy, PtrToInt8Ty, symtab->getType(), IntTy
3772 };
3773 llvm::StructType *moduleTy =
3774 llvm::StructType::get(CGM.getLLVMContext(),
3775 makeArrayRef(moduleEltTys).drop_back(unsigned(RuntimeVersion < 10)));
3776
3777 ConstantInitBuilder builder(CGM);
3778 auto module = builder.beginStruct(moduleTy);
3779 // Runtime version, used for ABI compatibility checking.
3780 module.addInt(LongTy, RuntimeVersion);
3781 // sizeof(ModuleTy)
3782 module.addInt(LongTy, CGM.getDataLayout().getTypeStoreSize(moduleTy));
3783
3784 // The path to the source file where this module was declared
3785 SourceManager &SM = CGM.getContext().getSourceManager();
3786 const FileEntry *mainFile = SM.getFileEntryForID(SM.getMainFileID());
3787 std::string path =
3788 (Twine(mainFile->getDir()->getName()) + "/" + mainFile->getName()).str();
3789 module.add(MakeConstantString(path, ".objc_source_file_name"));
3790 module.add(symtab);
3791
3792 if (RuntimeVersion >= 10) {
3793 switch (CGM.getLangOpts().getGC()) {
3794 case LangOptions::GCOnly:
3795 module.addInt(IntTy, 2);
3796 break;
3797 case LangOptions::NonGC:
3798 if (CGM.getLangOpts().ObjCAutoRefCount)
3799 module.addInt(IntTy, 1);
3800 else
3801 module.addInt(IntTy, 0);
3802 break;
3803 case LangOptions::HybridGC:
3804 module.addInt(IntTy, 1);
3805 break;
3806 }
3807 }
3808
3809 return module.finishAndCreateGlobal("", CGM.getPointerAlign());
3810 }();
3811
3812 // Create the load function calling the runtime entry point with the module
3813 // structure
3814 llvm::Function * LoadFunction = llvm::Function::Create(
3815 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), false),
3816 llvm::GlobalValue::InternalLinkage, ".objc_load_function",
3817 &TheModule);
3818 llvm::BasicBlock *EntryBB =
3819 llvm::BasicBlock::Create(VMContext, "entry", LoadFunction);
3820 CGBuilderTy Builder(CGM, VMContext);
3821 Builder.SetInsertPoint(EntryBB);
3822
3823 llvm::FunctionType *FT =
3824 llvm::FunctionType::get(Builder.getVoidTy(), module->getType(), true);
3825 llvm::FunctionCallee Register =
3826 CGM.CreateRuntimeFunction(FT, "__objc_exec_class");
3827 Builder.CreateCall(Register, module);
3828
3829 if (!ClassAliases.empty()) {
3830 llvm::Type *ArgTypes[2] = {PtrTy, PtrToInt8Ty};
3831 llvm::FunctionType *RegisterAliasTy =
3832 llvm::FunctionType::get(Builder.getVoidTy(),
3833 ArgTypes, false);
3834 llvm::Function *RegisterAlias = llvm::Function::Create(
3835 RegisterAliasTy,
3836 llvm::GlobalValue::ExternalWeakLinkage, "class_registerAlias_np",
3837 &TheModule);
3838 llvm::BasicBlock *AliasBB =
3839 llvm::BasicBlock::Create(VMContext, "alias", LoadFunction);
3840 llvm::BasicBlock *NoAliasBB =
3841 llvm::BasicBlock::Create(VMContext, "no_alias", LoadFunction);
3842
3843 // Branch based on whether the runtime provided class_registerAlias_np()
3844 llvm::Value *HasRegisterAlias = Builder.CreateICmpNE(RegisterAlias,
3845 llvm::Constant::getNullValue(RegisterAlias->getType()));
3846 Builder.CreateCondBr(HasRegisterAlias, AliasBB, NoAliasBB);
3847
3848 // The true branch (has alias registration function):
3849 Builder.SetInsertPoint(AliasBB);
3850 // Emit alias registration calls:
3851 for (std::vector<ClassAliasPair>::iterator iter = ClassAliases.begin();
3852 iter != ClassAliases.end(); ++iter) {
3853 llvm::Constant *TheClass =
3854 TheModule.getGlobalVariable("_OBJC_CLASS_" + iter->first, true);
3855 if (TheClass) {
3856 TheClass = llvm::ConstantExpr::getBitCast(TheClass, PtrTy);
3857 Builder.CreateCall(RegisterAlias,
3858 {TheClass, MakeConstantString(iter->second)});
3859 }
3860 }
3861 // Jump to end:
3862 Builder.CreateBr(NoAliasBB);
3863
3864 // Missing alias registration function, just return from the function:
3865 Builder.SetInsertPoint(NoAliasBB);
3866 }
3867 Builder.CreateRetVoid();
3868
3869 return LoadFunction;
3870}
3871
3872llvm::Function *CGObjCGNU::GenerateMethod(const ObjCMethodDecl *OMD,
3873 const ObjCContainerDecl *CD) {
3874 CodeGenTypes &Types = CGM.getTypes();
3875 llvm::FunctionType *MethodTy =
3876 Types.GetFunctionType(Types.arrangeObjCMethodDeclaration(OMD));
3877 std::string FunctionName = getSymbolNameForMethod(OMD);
3878
3879 llvm::Function *Method
3880 = llvm::Function::Create(MethodTy,
3881 llvm::GlobalValue::InternalLinkage,
3882 FunctionName,
3883 &TheModule);
3884 return Method;
3885}
3886
3887void CGObjCGNU::GenerateDirectMethodPrologue(CodeGenFunction &CGF,
3888 llvm::Function *Fn,
3889 const ObjCMethodDecl *OMD,
3890 const ObjCContainerDecl *CD) {
3891 // GNU runtime doesn't support direct calls at this time
3892}
3893
3894llvm::FunctionCallee CGObjCGNU::GetPropertyGetFunction() {
3895 return GetPropertyFn;
3896}
3897
3898llvm::FunctionCallee CGObjCGNU::GetPropertySetFunction() {
3899 return SetPropertyFn;
3900}
3901
3902llvm::FunctionCallee CGObjCGNU::GetOptimizedPropertySetFunction(bool atomic,
3903 bool copy) {
3904 return nullptr;
3905}
3906
3907llvm::FunctionCallee CGObjCGNU::GetGetStructFunction() {
3908 return GetStructPropertyFn;
3909}
3910
3911llvm::FunctionCallee CGObjCGNU::GetSetStructFunction() {
3912 return SetStructPropertyFn;
3913}
3914
3915llvm::FunctionCallee CGObjCGNU::GetCppAtomicObjectGetFunction() {
3916 return nullptr;
3917}
3918
3919llvm::FunctionCallee CGObjCGNU::GetCppAtomicObjectSetFunction() {
3920 return nullptr;
3921}
3922
3923llvm::FunctionCallee CGObjCGNU::EnumerationMutationFunction() {
3924 return EnumerationMutationFn;
3925}
3926
3927void CGObjCGNU::EmitSynchronizedStmt(CodeGenFunction &CGF,
3928 const ObjCAtSynchronizedStmt &S) {
3929 EmitAtSynchronizedStmt(CGF, S, SyncEnterFn, SyncExitFn);
3930}
3931
3932
3933void CGObjCGNU::EmitTryStmt(CodeGenFunction &CGF,
3934 const ObjCAtTryStmt &S) {
3935 // Unlike the Apple non-fragile runtimes, which also uses
3936 // unwind-based zero cost exceptions, the GNU Objective C runtime's
3937 // EH support isn't a veneer over C++ EH. Instead, exception
3938 // objects are created by objc_exception_throw and destroyed by
3939 // the personality function; this avoids the need for bracketing
3940 // catch handlers with calls to __blah_begin_catch/__blah_end_catch
3941 // (or even _Unwind_DeleteException), but probably doesn't
3942 // interoperate very well with foreign exceptions.
3943 //
3944 // In Objective-C++ mode, we actually emit something equivalent to the C++
3945 // exception handler.
3946 EmitTryCatchStmt(CGF, S, EnterCatchFn, ExitCatchFn, ExceptionReThrowFn);
3947}
3948
3949void CGObjCGNU::EmitThrowStmt(CodeGenFunction &CGF,
3950 const ObjCAtThrowStmt &S,
3951 bool ClearInsertionPoint) {
3952 llvm::Value *ExceptionAsObject;
3953 bool isRethrow = false;
3954
3955 if (const Expr *ThrowExpr = S.getThrowExpr()) {
3956 llvm::Value *Exception = CGF.EmitObjCThrowOperand(ThrowExpr);
3957 ExceptionAsObject = Exception;
3958 } else {
3959 assert((!CGF.ObjCEHValueStack.empty() && CGF.ObjCEHValueStack.back()) &&(static_cast<void> (0))
3960 "Unexpected rethrow outside @catch block.")(static_cast<void> (0));
3961 ExceptionAsObject = CGF.ObjCEHValueStack.back();
3962 isRethrow = true;
3963 }
3964 if (isRethrow && usesSEHExceptions) {
3965 // For SEH, ExceptionAsObject may be undef, because the catch handler is
3966 // not passed it for catchalls and so it is not visible to the catch
3967 // funclet. The real thrown object will still be live on the stack at this
3968 // point and will be rethrown. If we are explicitly rethrowing the object
3969 // that was passed into the `@catch` block, then this code path is not
3970 // reached and we will instead call `objc_exception_throw` with an explicit
3971 // argument.
3972 llvm::CallBase *Throw = CGF.EmitRuntimeCallOrInvoke(ExceptionReThrowFn);
3973 Throw->setDoesNotReturn();
3974 }
3975 else {
3976 ExceptionAsObject = CGF.Builder.CreateBitCast(ExceptionAsObject, IdTy);
3977 llvm::CallBase *Throw =
3978 CGF.EmitRuntimeCallOrInvoke(ExceptionThrowFn, ExceptionAsObject);
3979 Throw->setDoesNotReturn();
3980 }
3981 CGF.Builder.CreateUnreachable();
3982 if (ClearInsertionPoint)
3983 CGF.Builder.ClearInsertionPoint();
3984}
3985
3986llvm::Value * CGObjCGNU::EmitObjCWeakRead(CodeGenFunction &CGF,
3987 Address AddrWeakObj) {
3988 CGBuilderTy &B = CGF.Builder;
3989 AddrWeakObj = EnforceType(B, AddrWeakObj, PtrToIdTy);
3990 return B.CreateCall(WeakReadFn, AddrWeakObj.getPointer());
3991}
3992
3993void CGObjCGNU::EmitObjCWeakAssign(CodeGenFunction &CGF,
3994 llvm::Value *src, Address dst) {
3995 CGBuilderTy &B = CGF.Builder;
3996 src = EnforceType(B, src, IdTy);
3997 dst = EnforceType(B, dst, PtrToIdTy);
3998 B.CreateCall(WeakAssignFn, {src, dst.getPointer()});
3999}
4000
4001void CGObjCGNU::EmitObjCGlobalAssign(CodeGenFunction &CGF,
4002 llvm::Value *src, Address dst,
4003 bool threadlocal) {
4004 CGBuilderTy &B = CGF.Builder;
4005 src = EnforceType(B, src, IdTy);
4006 dst = EnforceType(B, dst, PtrToIdTy);
4007 // FIXME. Add threadloca assign API
4008 assert(!threadlocal && "EmitObjCGlobalAssign - Threal Local API NYI")(static_cast<void> (0));
4009 B.CreateCall(GlobalAssignFn, {src, dst.getPointer()});
4010}
4011
4012void CGObjCGNU::EmitObjCIvarAssign(CodeGenFunction &CGF,
4013 llvm::Value *src, Address dst,
4014 llvm::Value *ivarOffset) {
4015 CGBuilderTy &B = CGF.Builder;
4016 src = EnforceType(B, src, IdTy);
4017 dst = EnforceType(B, dst, IdTy);
4018 B.CreateCall(IvarAssignFn, {src, dst.getPointer(), ivarOffset});
4019}
4020
4021void CGObjCGNU::EmitObjCStrongCastAssign(CodeGenFunction &CGF,
4022 llvm::Value *src, Address dst) {
4023 CGBuilderTy &B = CGF.Builder;
4024 src = EnforceType(B, src, IdTy);
4025 dst = EnforceType(B, dst, PtrToIdTy);
4026 B.CreateCall(StrongCastAssignFn, {src, dst.getPointer()});
4027}
4028
4029void CGObjCGNU::EmitGCMemmoveCollectable(CodeGenFunction &CGF,
4030 Address DestPtr,
4031 Address SrcPtr,
4032 llvm::Value *Size) {
4033 CGBuilderTy &B = CGF.Builder;
4034 DestPtr = EnforceType(B, DestPtr, PtrTy);
4035 SrcPtr = EnforceType(B, SrcPtr, PtrTy);
4036
4037 B.CreateCall(MemMoveFn, {DestPtr.getPointer(), SrcPtr.getPointer(), Size});
4038}
4039
4040llvm::GlobalVariable *CGObjCGNU::ObjCIvarOffsetVariable(
4041 const ObjCInterfaceDecl *ID,
4042 const ObjCIvarDecl *Ivar) {
4043 const std::string Name = GetIVarOffsetVariableName(ID, Ivar);
4044 // Emit the variable and initialize it with what we think the correct value
4045 // is. This allows code compiled with non-fragile ivars to work correctly
4046 // when linked against code which isn't (most of the time).
4047 llvm::GlobalVariable *IvarOffsetPointer = TheModule.getNamedGlobal(Name);
4048 if (!IvarOffsetPointer)
4049 IvarOffsetPointer = new llvm::GlobalVariable(TheModule,
4050 llvm::Type::getInt32PtrTy(VMContext), false,
4051 llvm::GlobalValue::ExternalLinkage, nullptr, Name);
4052 return IvarOffsetPointer;
4053}
4054
4055LValue CGObjCGNU::EmitObjCValueForIvar(CodeGenFunction &CGF,
4056 QualType ObjectTy,
4057 llvm::Value *BaseValue,
4058 const ObjCIvarDecl *Ivar,
4059 unsigned CVRQualifiers) {
4060 const ObjCInterfaceDecl *ID =
4061 ObjectTy->castAs<ObjCObjectType>()->getInterface();
4062 return EmitValueForIvarAtOffset(CGF, ID, BaseValue, Ivar, CVRQualifiers,
4063 EmitIvarOffset(CGF, ID, Ivar));
4064}
4065
4066static const ObjCInterfaceDecl *FindIvarInterface(ASTContext &Context,
4067 const ObjCInterfaceDecl *OID,
4068 const ObjCIvarDecl *OIVD) {
4069 for (const ObjCIvarDecl *next = OID->all_declared_ivar_begin(); next;
4070 next = next->getNextIvar()) {
4071 if (OIVD == next)
4072 return OID;
4073 }
4074
4075 // Otherwise check in the super class.
4076 if (const ObjCInterfaceDecl *Super = OID->getSuperClass())
4077 return FindIvarInterface(Context, Super, OIVD);
4078
4079 return nullptr;
4080}
4081
4082llvm::Value *CGObjCGNU::EmitIvarOffset(CodeGenFunction &CGF,
4083 const ObjCInterfaceDecl *Interface,
4084 const ObjCIvarDecl *Ivar) {
4085 if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
4086 Interface = FindIvarInterface(CGM.getContext(), Interface, Ivar);
4087
4088 // The MSVC linker cannot have a single global defined as LinkOnceAnyLinkage
4089 // and ExternalLinkage, so create a reference to the ivar global and rely on
4090 // the definition being created as part of GenerateClass.
4091 if (RuntimeVersion < 10 ||
4092 CGF.CGM.getTarget().getTriple().isKnownWindowsMSVCEnvironment())
4093 return CGF.Builder.CreateZExtOrBitCast(
4094 CGF.Builder.CreateAlignedLoad(
4095 Int32Ty, CGF.Builder.CreateAlignedLoad(
4096 llvm::Type::getInt32PtrTy(VMContext),
4097 ObjCIvarOffsetVariable(Interface, Ivar),
4098 CGF.getPointerAlign(), "ivar"),
4099 CharUnits::fromQuantity(4)),
4100 PtrDiffTy);
4101 std::string name = "__objc_ivar_offset_value_" +
4102 Interface->getNameAsString() +"." + Ivar->getNameAsString();
4103 CharUnits Align = CGM.getIntAlign();
4104 llvm::Value *Offset = TheModule.getGlobalVariable(name);
4105 if (!Offset) {
4106 auto GV = new llvm::GlobalVariable(TheModule, IntTy,
4107 false, llvm::GlobalValue::LinkOnceAnyLinkage,
4108 llvm::Constant::getNullValue(IntTy), name);
4109 GV->setAlignment(Align.getAsAlign());
4110 Offset = GV;
4111 }
4112 Offset = CGF.Builder.CreateAlignedLoad(IntTy, Offset, Align);
4113 if (Offset->getType() != PtrDiffTy)
4114 Offset = CGF.Builder.CreateZExtOrBitCast(Offset, PtrDiffTy);
4115 return Offset;
4116 }
4117 uint64_t Offset = ComputeIvarBaseOffset(CGF.CGM, Interface, Ivar);
4118 return llvm::ConstantInt::get(PtrDiffTy, Offset, /*isSigned*/true);
4119}
4120
4121CGObjCRuntime *
4122clang::CodeGen::CreateGNUObjCRuntime(CodeGenModule &CGM) {
4123 auto Runtime = CGM.getLangOpts().ObjCRuntime;
4124 switch (Runtime.getKind()) {
4125 case ObjCRuntime::GNUstep:
4126 if (Runtime.getVersion() >= VersionTuple(2, 0))
4127 return new CGObjCGNUstep2(CGM);
4128 return new CGObjCGNUstep(CGM);
4129
4130 case ObjCRuntime::GCC:
4131 return new CGObjCGCC(CGM);
4132
4133 case ObjCRuntime::ObjFW:
4134 return new CGObjCObjFW(CGM);
4135
4136 case ObjCRuntime::FragileMacOSX:
4137 case ObjCRuntime::MacOSX:
4138 case ObjCRuntime::iOS:
4139 case ObjCRuntime::WatchOS:
4140 llvm_unreachable("these runtimes are not GNU runtimes")__builtin_unreachable();
4141 }
4142 llvm_unreachable("bad runtime")__builtin_unreachable();
4143}

/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/include/clang/AST/Type.h

1//===- Type.h - C Language Family Type Representation -----------*- C++ -*-===//
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/// \file
10/// C Language Family Type Representation
11///
12/// This file defines the clang::Type interface and subclasses, used to
13/// represent types for languages in the C family.
14//
15//===----------------------------------------------------------------------===//
16
17#ifndef LLVM_CLANG_AST_TYPE_H
18#define LLVM_CLANG_AST_TYPE_H
19
20#include "clang/AST/DependenceFlags.h"
21#include "clang/AST/NestedNameSpecifier.h"
22#include "clang/AST/TemplateName.h"
23#include "clang/Basic/AddressSpaces.h"
24#include "clang/Basic/AttrKinds.h"
25#include "clang/Basic/Diagnostic.h"
26#include "clang/Basic/ExceptionSpecificationType.h"
27#include "clang/Basic/LLVM.h"
28#include "clang/Basic/Linkage.h"
29#include "clang/Basic/PartialDiagnostic.h"
30#include "clang/Basic/SourceLocation.h"
31#include "clang/Basic/Specifiers.h"
32#include "clang/Basic/Visibility.h"
33#include "llvm/ADT/APInt.h"
34#include "llvm/ADT/APSInt.h"
35#include "llvm/ADT/ArrayRef.h"
36#include "llvm/ADT/FoldingSet.h"
37#include "llvm/ADT/None.h"
38#include "llvm/ADT/Optional.h"
39#include "llvm/ADT/PointerIntPair.h"
40#include "llvm/ADT/PointerUnion.h"
41#include "llvm/ADT/StringRef.h"
42#include "llvm/ADT/Twine.h"
43#include "llvm/ADT/iterator_range.h"
44#include "llvm/Support/Casting.h"
45#include "llvm/Support/Compiler.h"
46#include "llvm/Support/ErrorHandling.h"
47#include "llvm/Support/PointerLikeTypeTraits.h"
48#include "llvm/Support/TrailingObjects.h"
49#include "llvm/Support/type_traits.h"
50#include <cassert>
51#include <cstddef>
52#include <cstdint>
53#include <cstring>
54#include <string>
55#include <type_traits>
56#include <utility>
57
58namespace clang {
59
60class ExtQuals;
61class QualType;
62class ConceptDecl;
63class TagDecl;
64class TemplateParameterList;
65class Type;
66
67enum {
68 TypeAlignmentInBits = 4,
69 TypeAlignment = 1 << TypeAlignmentInBits
70};
71
72namespace serialization {
73 template <class T> class AbstractTypeReader;
74 template <class T> class AbstractTypeWriter;
75}
76
77} // namespace clang
78
79namespace llvm {
80
81 template <typename T>
82 struct PointerLikeTypeTraits;
83 template<>
84 struct PointerLikeTypeTraits< ::clang::Type*> {
85 static inline void *getAsVoidPointer(::clang::Type *P) { return P; }
86
87 static inline ::clang::Type *getFromVoidPointer(void *P) {
88 return static_cast< ::clang::Type*>(P);
89 }
90
91 static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
92 };
93
94 template<>
95 struct PointerLikeTypeTraits< ::clang::ExtQuals*> {
96 static inline void *getAsVoidPointer(::clang::ExtQuals *P) { return P; }
97
98 static inline ::clang::ExtQuals *getFromVoidPointer(void *P) {
99 return static_cast< ::clang::ExtQuals*>(P);
100 }
101
102 static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
103 };
104
105} // namespace llvm
106
107namespace clang {
108
109class ASTContext;
110template <typename> class CanQual;
111class CXXRecordDecl;
112class DeclContext;
113class EnumDecl;
114class Expr;
115class ExtQualsTypeCommonBase;
116class FunctionDecl;
117class IdentifierInfo;
118class NamedDecl;
119class ObjCInterfaceDecl;
120class ObjCProtocolDecl;
121class ObjCTypeParamDecl;
122struct PrintingPolicy;
123class RecordDecl;
124class Stmt;
125class TagDecl;
126class TemplateArgument;
127class TemplateArgumentListInfo;
128class TemplateArgumentLoc;
129class TemplateTypeParmDecl;
130class TypedefNameDecl;
131class UnresolvedUsingTypenameDecl;
132
133using CanQualType = CanQual<Type>;
134
135// Provide forward declarations for all of the *Type classes.
136#define TYPE(Class, Base) class Class##Type;
137#include "clang/AST/TypeNodes.inc"
138
139/// The collection of all-type qualifiers we support.
140/// Clang supports five independent qualifiers:
141/// * C99: const, volatile, and restrict
142/// * MS: __unaligned
143/// * Embedded C (TR18037): address spaces
144/// * Objective C: the GC attributes (none, weak, or strong)
145class Qualifiers {
146public:
147 enum TQ { // NOTE: These flags must be kept in sync with DeclSpec::TQ.
148 Const = 0x1,
149 Restrict = 0x2,
150 Volatile = 0x4,
151 CVRMask = Const | Volatile | Restrict
152 };
153
154 enum GC {
155 GCNone = 0,
156 Weak,
157 Strong
158 };
159
160 enum ObjCLifetime {
161 /// There is no lifetime qualification on this type.
162 OCL_None,
163
164 /// This object can be modified without requiring retains or
165 /// releases.
166 OCL_ExplicitNone,
167
168 /// Assigning into this object requires the old value to be
169 /// released and the new value to be retained. The timing of the
170 /// release of the old value is inexact: it may be moved to
171 /// immediately after the last known point where the value is
172 /// live.
173 OCL_Strong,
174
175 /// Reading or writing from this object requires a barrier call.
176 OCL_Weak,
177
178 /// Assigning into this object requires a lifetime extension.
179 OCL_Autoreleasing
180 };
181
182 enum {
183 /// The maximum supported address space number.
184 /// 23 bits should be enough for anyone.
185 MaxAddressSpace = 0x7fffffu,
186
187 /// The width of the "fast" qualifier mask.
188 FastWidth = 3,
189
190 /// The fast qualifier mask.
191 FastMask = (1 << FastWidth) - 1
192 };
193
194 /// Returns the common set of qualifiers while removing them from
195 /// the given sets.
196 static Qualifiers removeCommonQualifiers(Qualifiers &L, Qualifiers &R) {
197 // If both are only CVR-qualified, bit operations are sufficient.
198 if (!(L.Mask & ~CVRMask) && !(R.Mask & ~CVRMask)) {
199 Qualifiers Q;
200 Q.Mask = L.Mask & R.Mask;
201 L.Mask &= ~Q.Mask;
202 R.Mask &= ~Q.Mask;
203 return Q;
204 }
205
206 Qualifiers Q;
207 unsigned CommonCRV = L.getCVRQualifiers() & R.getCVRQualifiers();
208 Q.addCVRQualifiers(CommonCRV);
209 L.removeCVRQualifiers(CommonCRV);
210 R.removeCVRQualifiers(CommonCRV);
211
212 if (L.getObjCGCAttr() == R.getObjCGCAttr()) {
213 Q.setObjCGCAttr(L.getObjCGCAttr());
214 L.removeObjCGCAttr();
215 R.removeObjCGCAttr();
216 }
217
218 if (L.getObjCLifetime() == R.getObjCLifetime()) {
219 Q.setObjCLifetime(L.getObjCLifetime());
220 L.removeObjCLifetime();
221 R.removeObjCLifetime();
222 }
223
224 if (L.getAddressSpace() == R.getAddressSpace()) {
225 Q.setAddressSpace(L.getAddressSpace());
226 L.removeAddressSpace();
227 R.removeAddressSpace();
228 }
229 return Q;
230 }
231
232 static Qualifiers fromFastMask(unsigned Mask) {
233 Qualifiers Qs;
234 Qs.addFastQualifiers(Mask);
235 return Qs;
236 }
237
238 static Qualifiers fromCVRMask(unsigned CVR) {
239 Qualifiers Qs;
240 Qs.addCVRQualifiers(CVR);
241 return Qs;
242 }
243
244 static Qualifiers fromCVRUMask(unsigned CVRU) {
245 Qualifiers Qs;
246 Qs.addCVRUQualifiers(CVRU);
247 return Qs;
248 }
249
250 // Deserialize qualifiers from an opaque representation.
251 static Qualifiers fromOpaqueValue(unsigned opaque) {
252 Qualifiers Qs;
253 Qs.Mask = opaque;
254 return Qs;
255 }
256
257 // Serialize these qualifiers into an opaque representation.
258 unsigned getAsOpaqueValue() const {
259 return Mask;
260 }
261
262 bool hasConst() const { return Mask & Const; }
263 bool hasOnlyConst() const { return Mask == Const; }
264 void removeConst() { Mask &= ~Const; }
265 void addConst() { Mask |= Const; }
266
267 bool hasVolatile() const { return Mask & Volatile; }
268 bool hasOnlyVolatile() const { return Mask == Volatile; }
269 void removeVolatile() { Mask &= ~Volatile; }
270 void addVolatile() { Mask |= Volatile; }
271
272 bool hasRestrict() const { return Mask & Restrict; }
273 bool hasOnlyRestrict() const { return Mask == Restrict; }
274 void removeRestrict() { Mask &= ~Restrict; }
275 void addRestrict() { Mask |= Restrict; }
276
277 bool hasCVRQualifiers() const { return getCVRQualifiers(); }
278 unsigned getCVRQualifiers() const { return Mask & CVRMask; }
279 unsigned getCVRUQualifiers() const { return Mask & (CVRMask | UMask); }
280
281 void setCVRQualifiers(unsigned mask) {
282 assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")(static_cast<void> (0));
283 Mask = (Mask & ~CVRMask) | mask;
284 }
285 void removeCVRQualifiers(unsigned mask) {
286 assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")(static_cast<void> (0));
287 Mask &= ~mask;
288 }
289 void removeCVRQualifiers() {
290 removeCVRQualifiers(CVRMask);
291 }
292 void addCVRQualifiers(unsigned mask) {
293 assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")(static_cast<void> (0));
294 Mask |= mask;
295 }
296 void addCVRUQualifiers(unsigned mask) {
297 assert(!(mask & ~CVRMask & ~UMask) && "bitmask contains non-CVRU bits")(static_cast<void> (0));
298 Mask |= mask;
299 }
300
301 bool hasUnaligned() const { return Mask & UMask; }
302 void setUnaligned(bool flag) {
303 Mask = (Mask & ~UMask) | (flag ? UMask : 0);
304 }
305 void removeUnaligned() { Mask &= ~UMask; }
306 void addUnaligned() { Mask |= UMask; }
307
308 bool hasObjCGCAttr() const { return Mask & GCAttrMask; }
309 GC getObjCGCAttr() const { return GC((Mask & GCAttrMask) >> GCAttrShift); }
310 void setObjCGCAttr(GC type) {
311 Mask = (Mask & ~GCAttrMask) | (type << GCAttrShift);
312 }
313 void removeObjCGCAttr() { setObjCGCAttr(GCNone); }
314 void addObjCGCAttr(GC type) {
315 assert(type)(static_cast<void> (0));
316 setObjCGCAttr(type);
317 }
318 Qualifiers withoutObjCGCAttr() const {
319 Qualifiers qs = *this;
320 qs.removeObjCGCAttr();
321 return qs;
322 }
323 Qualifiers withoutObjCLifetime() const {
324 Qualifiers qs = *this;
325 qs.removeObjCLifetime();
326 return qs;
327 }
328 Qualifiers withoutAddressSpace() const {
329 Qualifiers qs = *this;
330 qs.removeAddressSpace();
331 return qs;
332 }
333
334 bool hasObjCLifetime() const { return Mask & LifetimeMask; }
335 ObjCLifetime getObjCLifetime() const {
336 return ObjCLifetime((Mask & LifetimeMask) >> LifetimeShift);
337 }
338 void setObjCLifetime(ObjCLifetime type) {
339 Mask = (Mask & ~LifetimeMask) | (type << LifetimeShift);
340 }
341 void removeObjCLifetime() { setObjCLifetime(OCL_None); }
342 void addObjCLifetime(ObjCLifetime type) {
343 assert(type)(static_cast<void> (0));
344 assert(!hasObjCLifetime())(static_cast<void> (0));
345 Mask |= (type << LifetimeShift);
346 }
347
348 /// True if the lifetime is neither None or ExplicitNone.
349 bool hasNonTrivialObjCLifetime() const {
350 ObjCLifetime lifetime = getObjCLifetime();
351 return (lifetime > OCL_ExplicitNone);
352 }
353
354 /// True if the lifetime is either strong or weak.
355 bool hasStrongOrWeakObjCLifetime() const {
356 ObjCLifetime lifetime = getObjCLifetime();
357 return (lifetime == OCL_Strong || lifetime == OCL_Weak);
358 }
359
360 bool hasAddressSpace() const { return Mask & AddressSpaceMask; }
361 LangAS getAddressSpace() const {
362 return static_cast<LangAS>(Mask >> AddressSpaceShift);
363 }
364 bool hasTargetSpecificAddressSpace() const {
365 return isTargetAddressSpace(getAddressSpace());
366 }
367 /// Get the address space attribute value to be printed by diagnostics.
368 unsigned getAddressSpaceAttributePrintValue() const {
369 auto Addr = getAddressSpace();
370 // This function is not supposed to be used with language specific
371 // address spaces. If that happens, the diagnostic message should consider
372 // printing the QualType instead of the address space value.
373 assert(Addr == LangAS::Default || hasTargetSpecificAddressSpace())(static_cast<void> (0));
374 if (Addr != LangAS::Default)
375 return toTargetAddressSpace(Addr);
376 // TODO: The diagnostic messages where Addr may be 0 should be fixed
377 // since it cannot differentiate the situation where 0 denotes the default
378 // address space or user specified __attribute__((address_space(0))).
379 return 0;
380 }
381 void setAddressSpace(LangAS space) {
382 assert((unsigned)space <= MaxAddressSpace)(static_cast<void> (0));
383 Mask = (Mask & ~AddressSpaceMask)
384 | (((uint32_t) space) << AddressSpaceShift);
385 }
386 void removeAddressSpace() { setAddressSpace(LangAS::Default); }
387 void addAddressSpace(LangAS space) {
388 assert(space != LangAS::Default)(static_cast<void> (0));
389 setAddressSpace(space);
390 }
391
392 // Fast qualifiers are those that can be allocated directly
393 // on a QualType object.
394 bool hasFastQualifiers() const { return getFastQualifiers(); }
395 unsigned getFastQualifiers() const { return Mask & FastMask; }
396 void setFastQualifiers(unsigned mask) {
397 assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")(static_cast<void> (0));
398 Mask = (Mask & ~FastMask) | mask;
399 }
400 void removeFastQualifiers(unsigned mask) {
401 assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")(static_cast<void> (0));
402 Mask &= ~mask;
403 }
404 void removeFastQualifiers() {
405 removeFastQualifiers(FastMask);
406 }
407 void addFastQualifiers(unsigned mask) {
408 assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")(static_cast<void> (0));
409 Mask |= mask;
410 }
411
412 /// Return true if the set contains any qualifiers which require an ExtQuals
413 /// node to be allocated.
414 bool hasNonFastQualifiers() const { return Mask & ~FastMask; }
415 Qualifiers getNonFastQualifiers() const {
416 Qualifiers Quals = *this;
417 Quals.setFastQualifiers(0);
418 return Quals;
419 }
420
421 /// Return true if the set contains any qualifiers.
422 bool hasQualifiers() const { return Mask; }
423 bool empty() const { return !Mask; }
424
425 /// Add the qualifiers from the given set to this set.
426 void addQualifiers(Qualifiers Q) {
427 // If the other set doesn't have any non-boolean qualifiers, just
428 // bit-or it in.
429 if (!(Q.Mask & ~CVRMask))
430 Mask |= Q.Mask;
431 else {
432 Mask |= (Q.Mask & CVRMask);
433 if (Q.hasAddressSpace())
434 addAddressSpace(Q.getAddressSpace());
435 if (Q.hasObjCGCAttr())
436 addObjCGCAttr(Q.getObjCGCAttr());
437 if (Q.hasObjCLifetime())
438 addObjCLifetime(Q.getObjCLifetime());
439 }
440 }
441
442 /// Remove the qualifiers from the given set from this set.
443 void removeQualifiers(Qualifiers Q) {
444 // If the other set doesn't have any non-boolean qualifiers, just
445 // bit-and the inverse in.
446 if (!(Q.Mask & ~CVRMask))
447 Mask &= ~Q.Mask;
448 else {
449 Mask &= ~(Q.Mask & CVRMask);
450 if (getObjCGCAttr() == Q.getObjCGCAttr())
451 removeObjCGCAttr();
452 if (getObjCLifetime() == Q.getObjCLifetime())
453 removeObjCLifetime();
454 if (getAddressSpace() == Q.getAddressSpace())
455 removeAddressSpace();
456 }
457 }
458
459 /// Add the qualifiers from the given set to this set, given that
460 /// they don't conflict.
461 void addConsistentQualifiers(Qualifiers qs) {
462 assert(getAddressSpace() == qs.getAddressSpace() ||(static_cast<void> (0))
463 !hasAddressSpace() || !qs.hasAddressSpace())(static_cast<void> (0));
464 assert(getObjCGCAttr() == qs.getObjCGCAttr() ||(static_cast<void> (0))
465 !hasObjCGCAttr() || !qs.hasObjCGCAttr())(static_cast<void> (0));
466 assert(getObjCLifetime() == qs.getObjCLifetime() ||(static_cast<void> (0))
467 !hasObjCLifetime() || !qs.hasObjCLifetime())(static_cast<void> (0));
468 Mask |= qs.Mask;
469 }
470
471 /// Returns true if address space A is equal to or a superset of B.
472 /// OpenCL v2.0 defines conversion rules (OpenCLC v2.0 s6.5.5) and notion of
473 /// overlapping address spaces.
474 /// CL1.1 or CL1.2:
475 /// every address space is a superset of itself.
476 /// CL2.0 adds:
477 /// __generic is a superset of any address space except for __constant.
478 static bool isAddressSpaceSupersetOf(LangAS A, LangAS B) {
479 // Address spaces must match exactly.
480 return A == B ||
481 // Otherwise in OpenCLC v2.0 s6.5.5: every address space except
482 // for __constant can be used as __generic.
483 (A == LangAS::opencl_generic && B != LangAS::opencl_constant) ||
484 // We also define global_device and global_host address spaces,
485 // to distinguish global pointers allocated on host from pointers
486 // allocated on device, which are a subset of __global.
487 (A == LangAS::opencl_global && (B == LangAS::opencl_global_device ||
488 B == LangAS::opencl_global_host)) ||
489 (A == LangAS::sycl_global && (B == LangAS::sycl_global_device ||
490 B == LangAS::sycl_global_host)) ||
491 // Consider pointer size address spaces to be equivalent to default.
492 ((isPtrSizeAddressSpace(A) || A == LangAS::Default) &&
493 (isPtrSizeAddressSpace(B) || B == LangAS::Default)) ||
494 // Default is a superset of SYCL address spaces.
495 (A == LangAS::Default &&
496 (B == LangAS::sycl_private || B == LangAS::sycl_local ||
497 B == LangAS::sycl_global || B == LangAS::sycl_global_device ||
498 B == LangAS::sycl_global_host)) ||
499 // In HIP device compilation, any cuda address space is allowed
500 // to implicitly cast into the default address space.
501 (A == LangAS::Default &&
502 (B == LangAS::cuda_constant || B == LangAS::cuda_device ||
503 B == LangAS::cuda_shared));
504 }
505
506 /// Returns true if the address space in these qualifiers is equal to or
507 /// a superset of the address space in the argument qualifiers.
508 bool isAddressSpaceSupersetOf(Qualifiers other) const {
509 return isAddressSpaceSupersetOf(getAddressSpace(), other.getAddressSpace());
510 }
511
512 /// Determines if these qualifiers compatibly include another set.
513 /// Generally this answers the question of whether an object with the other
514 /// qualifiers can be safely used as an object with these qualifiers.
515 bool compatiblyIncludes(Qualifiers other) const {
516 return isAddressSpaceSupersetOf(other) &&
517 // ObjC GC qualifiers can match, be added, or be removed, but can't
518 // be changed.
519 (getObjCGCAttr() == other.getObjCGCAttr() || !hasObjCGCAttr() ||
520 !other.hasObjCGCAttr()) &&
521 // ObjC lifetime qualifiers must match exactly.
522 getObjCLifetime() == other.getObjCLifetime() &&
523 // CVR qualifiers may subset.
524 (((Mask & CVRMask) | (other.Mask & CVRMask)) == (Mask & CVRMask)) &&
525 // U qualifier may superset.
526 (!other.hasUnaligned() || hasUnaligned());
527 }
528
529 /// Determines if these qualifiers compatibly include another set of
530 /// qualifiers from the narrow perspective of Objective-C ARC lifetime.
531 ///
532 /// One set of Objective-C lifetime qualifiers compatibly includes the other
533 /// if the lifetime qualifiers match, or if both are non-__weak and the
534 /// including set also contains the 'const' qualifier, or both are non-__weak
535 /// and one is None (which can only happen in non-ARC modes).
536 bool compatiblyIncludesObjCLifetime(Qualifiers other) const {
537 if (getObjCLifetime() == other.getObjCLifetime())
538 return true;
539
540 if (getObjCLifetime() == OCL_Weak || other.getObjCLifetime() == OCL_Weak)
541 return false;
542
543 if (getObjCLifetime() == OCL_None || other.getObjCLifetime() == OCL_None)
544 return true;
545
546 return hasConst();
547 }
548
549 /// Determine whether this set of qualifiers is a strict superset of
550 /// another set of qualifiers, not considering qualifier compatibility.
551 bool isStrictSupersetOf(Qualifiers Other) const;
552
553 bool operator==(Qualifiers Other) const { return Mask == Other.Mask; }
554 bool operator!=(Qualifiers Other) const { return Mask != Other.Mask; }
555
556 explicit operator bool() const { return hasQualifiers(); }
557
558 Qualifiers &operator+=(Qualifiers R) {
559 addQualifiers(R);
560 return *this;
561 }
562
563 // Union two qualifier sets. If an enumerated qualifier appears
564 // in both sets, use the one from the right.
565 friend Qualifiers operator+(Qualifiers L, Qualifiers R) {
566 L += R;
567 return L;
568 }
569
570 Qualifiers &operator-=(Qualifiers R) {
571 removeQualifiers(R);
572 return *this;
573 }
574
575 /// Compute the difference between two qualifier sets.
576 friend Qualifiers operator-(Qualifiers L, Qualifiers R) {
577 L -= R;
578 return L;
579 }
580
581 std::string getAsString() const;
582 std::string getAsString(const PrintingPolicy &Policy) const;
583
584 static std::string getAddrSpaceAsString(LangAS AS);
585
586 bool isEmptyWhenPrinted(const PrintingPolicy &Policy) const;
587 void print(raw_ostream &OS, const PrintingPolicy &Policy,
588 bool appendSpaceIfNonEmpty = false) const;
589
590 void Profile(llvm::FoldingSetNodeID &ID) const {
591 ID.AddInteger(Mask);
592 }
593
594private:
595 // bits: |0 1 2|3|4 .. 5|6 .. 8|9 ... 31|
596 // |C R V|U|GCAttr|Lifetime|AddressSpace|
597 uint32_t Mask = 0;
598
599 static const uint32_t UMask = 0x8;
600 static const uint32_t UShift = 3;
601 static const uint32_t GCAttrMask = 0x30;
602 static const uint32_t GCAttrShift = 4;
603 static const uint32_t LifetimeMask = 0x1C0;
604 static const uint32_t LifetimeShift = 6;
605 static const uint32_t AddressSpaceMask =
606 ~(CVRMask | UMask | GCAttrMask | LifetimeMask);
607 static const uint32_t AddressSpaceShift = 9;
608};
609
610/// A std::pair-like structure for storing a qualified type split
611/// into its local qualifiers and its locally-unqualified type.
612struct SplitQualType {
613 /// The locally-unqualified type.
614 const Type *Ty = nullptr;
615
616 /// The local qualifiers.
617 Qualifiers Quals;
618
619 SplitQualType() = default;
620 SplitQualType(const Type *ty, Qualifiers qs) : Ty(ty), Quals(qs) {}
621
622 SplitQualType getSingleStepDesugaredType() const; // end of this file
623
624 // Make std::tie work.
625 std::pair<const Type *,Qualifiers> asPair() const {
626 return std::pair<const Type *, Qualifiers>(Ty, Quals);
627 }
628
629 friend bool operator==(SplitQualType a, SplitQualType b) {
630 return a.Ty == b.Ty && a.Quals == b.Quals;
631 }
632 friend bool operator!=(SplitQualType a, SplitQualType b) {
633 return a.Ty != b.Ty || a.Quals != b.Quals;
634 }
635};
636
637/// The kind of type we are substituting Objective-C type arguments into.
638///
639/// The kind of substitution affects the replacement of type parameters when
640/// no concrete type information is provided, e.g., when dealing with an
641/// unspecialized type.
642enum class ObjCSubstitutionContext {
643 /// An ordinary type.
644 Ordinary,
645
646 /// The result type of a method or function.
647 Result,
648
649 /// The parameter type of a method or function.
650 Parameter,
651
652 /// The type of a property.
653 Property,
654
655 /// The superclass of a type.
656 Superclass,
657};
658
659/// A (possibly-)qualified type.
660///
661/// For efficiency, we don't store CV-qualified types as nodes on their
662/// own: instead each reference to a type stores the qualifiers. This
663/// greatly reduces the number of nodes we need to allocate for types (for
664/// example we only need one for 'int', 'const int', 'volatile int',
665/// 'const volatile int', etc).
666///
667/// As an added efficiency bonus, instead of making this a pair, we
668/// just store the two bits we care about in the low bits of the
669/// pointer. To handle the packing/unpacking, we make QualType be a
670/// simple wrapper class that acts like a smart pointer. A third bit
671/// indicates whether there are extended qualifiers present, in which
672/// case the pointer points to a special structure.
673class QualType {
674 friend class QualifierCollector;
675
676 // Thankfully, these are efficiently composable.
677 llvm::PointerIntPair<llvm::PointerUnion<const Type *, const ExtQuals *>,
678 Qualifiers::FastWidth> Value;
679
680 const ExtQuals *getExtQualsUnsafe() const {
681 return Value.getPointer().get<const ExtQuals*>();
682 }
683
684 const Type *getTypePtrUnsafe() const {
685 return Value.getPointer().get<const Type*>();
686 }
687
688 const ExtQualsTypeCommonBase *getCommonPtr() const {
689 assert(!isNull() && "Cannot retrieve a NULL type pointer")(static_cast<void> (0));
690 auto CommonPtrVal = reinterpret_cast<uintptr_t>(Value.getOpaqueValue());
691 CommonPtrVal &= ~(uintptr_t)((1 << TypeAlignmentInBits) - 1);
692 return reinterpret_cast<ExtQualsTypeCommonBase*>(CommonPtrVal);
693 }
694
695public:
696 QualType() = default;
697 QualType(const Type *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
698 QualType(const ExtQuals *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
699
700 unsigned getLocalFastQualifiers() const { return Value.getInt(); }
701 void setLocalFastQualifiers(unsigned Quals) { Value.setInt(Quals); }
702
703 /// Retrieves a pointer to the underlying (unqualified) type.
704 ///
705 /// This function requires that the type not be NULL. If the type might be
706 /// NULL, use the (slightly less efficient) \c getTypePtrOrNull().
707 const Type *getTypePtr() const;
708
709 const Type *getTypePtrOrNull() const;
710
711 /// Retrieves a pointer to the name of the base type.
712 const IdentifierInfo *getBaseTypeIdentifier() const;
713
714 /// Divides a QualType into its unqualified type and a set of local
715 /// qualifiers.
716 SplitQualType split() const;
717
718 void *getAsOpaquePtr() const { return Value.getOpaqueValue(); }
719
720 static QualType getFromOpaquePtr(const void *Ptr) {
721 QualType T;
722 T.Value.setFromOpaqueValue(const_cast<void*>(Ptr));
723 return T;
724 }
725
726 const Type &operator*() const {
727 return *getTypePtr();
728 }
729
730 const Type *operator->() const {
731 return getTypePtr();
732 }
733
734 bool isCanonical() const;
735 bool isCanonicalAsParam() const;
736
737 /// Return true if this QualType doesn't point to a type yet.
738 bool isNull() const {
739 return Value.getPointer().isNull();
740 }
741
742 /// Determine whether this particular QualType instance has the
743 /// "const" qualifier set, without looking through typedefs that may have
744 /// added "const" at a different level.
745 bool isLocalConstQualified() const {
746 return (getLocalFastQualifiers() & Qualifiers::Const);
747 }
748
749 /// Determine whether this type is const-qualified.
750 bool isConstQualified() const;
751
752 /// Determine whether this particular QualType instance has the
753 /// "restrict" qualifier set, without looking through typedefs that may have
754 /// added "restrict" at a different level.
755 bool isLocalRestrictQualified() const {
756 return (getLocalFastQualifiers() & Qualifiers::Restrict);
757 }
758
759 /// Determine whether this type is restrict-qualified.
760 bool isRestrictQualified() const;
761
762 /// Determine whether this particular QualType instance has the
763 /// "volatile" qualifier set, without looking through typedefs that may have
764 /// added "volatile" at a different level.
765 bool isLocalVolatileQualified() const {
766 return (getLocalFastQualifiers() & Qualifiers::Volatile);
767 }
768
769 /// Determine whether this type is volatile-qualified.
770 bool isVolatileQualified() const;
771
772 /// Determine whether this particular QualType instance has any
773 /// qualifiers, without looking through any typedefs that might add
774 /// qualifiers at a different level.
775 bool hasLocalQualifiers() const {
776 return getLocalFastQualifiers() || hasLocalNonFastQualifiers();
777 }
778
779 /// Determine whether this type has any qualifiers.
780 bool hasQualifiers() const;
781
782 /// Determine whether this particular QualType instance has any
783 /// "non-fast" qualifiers, e.g., those that are stored in an ExtQualType
784 /// instance.
785 bool hasLocalNonFastQualifiers() const {
786 return Value.getPointer().is<const ExtQuals*>();
787 }
788
789 /// Retrieve the set of qualifiers local to this particular QualType
790 /// instance, not including any qualifiers acquired through typedefs or
791 /// other sugar.
792 Qualifiers getLocalQualifiers() const;
793
794 /// Retrieve the set of qualifiers applied to this type.
795 Qualifiers getQualifiers() const;
796
797 /// Retrieve the set of CVR (const-volatile-restrict) qualifiers
798 /// local to this particular QualType instance, not including any qualifiers
799 /// acquired through typedefs or other sugar.
800 unsigned getLocalCVRQualifiers() const {
801 return getLocalFastQualifiers();
802 }
803
804 /// Retrieve the set of CVR (const-volatile-restrict) qualifiers
805 /// applied to this type.
806 unsigned getCVRQualifiers() const;
807
808 bool isConstant(const ASTContext& Ctx) const {
809 return QualType::isConstant(*this, Ctx);
810 }
811
812 /// Determine whether this is a Plain Old Data (POD) type (C++ 3.9p10).
813 bool isPODType(const ASTContext &Context) const;
814
815 /// Return true if this is a POD type according to the rules of the C++98
816 /// standard, regardless of the current compilation's language.
817 bool isCXX98PODType(const ASTContext &Context) const;
818
819 /// Return true if this is a POD type according to the more relaxed rules
820 /// of the C++11 standard, regardless of the current compilation's language.
821 /// (C++0x [basic.types]p9). Note that, unlike
822 /// CXXRecordDecl::isCXX11StandardLayout, this takes DRs into account.
823 bool isCXX11PODType(const ASTContext &Context) const;
824
825 /// Return true if this is a trivial type per (C++0x [basic.types]p9)
826 bool isTrivialType(const ASTContext &Context) const;
827
828 /// Return true if this is a trivially copyable type (C++0x [basic.types]p9)
829 bool isTriviallyCopyableType(const ASTContext &Context) const;
830
831
832 /// Returns true if it is a class and it might be dynamic.
833 bool mayBeDynamicClass() const;
834
835 /// Returns true if it is not a class or if the class might not be dynamic.
836 bool mayBeNotDynamicClass() const;
837
838 // Don't promise in the API that anything besides 'const' can be
839 // easily added.
840
841 /// Add the `const` type qualifier to this QualType.
842 void addConst() {
843 addFastQualifiers(Qualifiers::Const);
844 }
845 QualType withConst() const {
846 return withFastQualifiers(Qualifiers::Const);
847 }
848
849 /// Add the `volatile` type qualifier to this QualType.
850 void addVolatile() {
851 addFastQualifiers(Qualifiers::Volatile);
852 }
853 QualType withVolatile() const {
854 return withFastQualifiers(Qualifiers::Volatile);
855 }
856
857 /// Add the `restrict` qualifier to this QualType.
858 void addRestrict() {
859 addFastQualifiers(Qualifiers::Restrict);
860 }
861 QualType withRestrict() const {
862 return withFastQualifiers(Qualifiers::Restrict);
863 }
864
865 QualType withCVRQualifiers(unsigned CVR) const {
866 return withFastQualifiers(CVR);
867 }
868
869 void addFastQualifiers(unsigned TQs) {
870 assert(!(TQs & ~Qualifiers::FastMask)(static_cast<void> (0))
871 && "non-fast qualifier bits set in mask!")(static_cast<void> (0));
872 Value.setInt(Value.getInt() | TQs);
873 }
874
875 void removeLocalConst();
876 void removeLocalVolatile();
877 void removeLocalRestrict();
878 void removeLocalCVRQualifiers(unsigned Mask);
879
880 void removeLocalFastQualifiers() { Value.setInt(0); }
881 void removeLocalFastQualifiers(unsigned Mask) {
882 assert(!(Mask & ~Qualifiers::FastMask) && "mask has non-fast qualifiers")(static_cast<void> (0));
883 Value.setInt(Value.getInt() & ~Mask);
884 }
885
886 // Creates a type with the given qualifiers in addition to any
887 // qualifiers already on this type.
888 QualType withFastQualifiers(unsigned TQs) const {
889 QualType T = *this;
890 T.addFastQualifiers(TQs);
891 return T;
892 }
893
894 // Creates a type with exactly the given fast qualifiers, removing
895 // any existing fast qualifiers.
896 QualType withExactLocalFastQualifiers(unsigned TQs) const {
897 return withoutLocalFastQualifiers().withFastQualifiers(TQs);
898 }
899
900 // Removes fast qualifiers, but leaves any extended qualifiers in place.
901 QualType withoutLocalFastQualifiers() const {
902 QualType T = *this;
903 T.removeLocalFastQualifiers();
904 return T;
905 }
906
907 QualType getCanonicalType() const;
908
909 /// Return this type with all of the instance-specific qualifiers
910 /// removed, but without removing any qualifiers that may have been applied
911 /// through typedefs.
912 QualType getLocalUnqualifiedType() const { return QualType(getTypePtr(), 0); }
913
914 /// Retrieve the unqualified variant of the given type,
915 /// removing as little sugar as possible.
916 ///
917 /// This routine looks through various kinds of sugar to find the
918 /// least-desugared type that is unqualified. For example, given:
919 ///
920 /// \code
921 /// typedef int Integer;
922 /// typedef const Integer CInteger;
923 /// typedef CInteger DifferenceType;
924 /// \endcode
925 ///
926 /// Executing \c getUnqualifiedType() on the type \c DifferenceType will
927 /// desugar until we hit the type \c Integer, which has no qualifiers on it.
928 ///
929 /// The resulting type might still be qualified if it's sugar for an array
930 /// type. To strip qualifiers even from within a sugared array type, use
931 /// ASTContext::getUnqualifiedArrayType.
932 inline QualType getUnqualifiedType() const;
933
934 /// Retrieve the unqualified variant of the given type, removing as little
935 /// sugar as possible.
936 ///
937 /// Like getUnqualifiedType(), but also returns the set of
938 /// qualifiers that were built up.
939 ///
940 /// The resulting type might still be qualified if it's sugar for an array
941 /// type. To strip qualifiers even from within a sugared array type, use
942 /// ASTContext::getUnqualifiedArrayType.
943 inline SplitQualType getSplitUnqualifiedType() const;
944
945 /// Determine whether this type is more qualified than the other
946 /// given type, requiring exact equality for non-CVR qualifiers.
947 bool isMoreQualifiedThan(QualType Other) const;
948
949 /// Determine whether this type is at least as qualified as the other
950 /// given type, requiring exact equality for non-CVR qualifiers.
951 bool isAtLeastAsQualifiedAs(QualType Other) const;
952
953 QualType getNonReferenceType() const;
954
955 /// Determine the type of a (typically non-lvalue) expression with the
956 /// specified result type.
957 ///
958 /// This routine should be used for expressions for which the return type is
959 /// explicitly specified (e.g., in a cast or call) and isn't necessarily
960 /// an lvalue. It removes a top-level reference (since there are no
961 /// expressions of reference type) and deletes top-level cvr-qualifiers
962 /// from non-class types (in C++) or all types (in C).
963 QualType getNonLValueExprType(const ASTContext &Context) const;
964
965 /// Remove an outer pack expansion type (if any) from this type. Used as part
966 /// of converting the type of a declaration to the type of an expression that
967 /// references that expression. It's meaningless for an expression to have a
968 /// pack expansion type.
969 QualType getNonPackExpansionType() const;
970
971 /// Return the specified type with any "sugar" removed from
972 /// the type. This takes off typedefs, typeof's etc. If the outer level of
973 /// the type is already concrete, it returns it unmodified. This is similar
974 /// to getting the canonical type, but it doesn't remove *all* typedefs. For
975 /// example, it returns "T*" as "T*", (not as "int*"), because the pointer is
976 /// concrete.
977 ///
978 /// Qualifiers are left in place.
979 QualType getDesugaredType(const ASTContext &Context) const {
980 return getDesugaredType(*this, Context);
981 }
982
983 SplitQualType getSplitDesugaredType() const {
984 return getSplitDesugaredType(*this);
985 }
986
987 /// Return the specified type with one level of "sugar" removed from
988 /// the type.
989 ///
990 /// This routine takes off the first typedef, typeof, etc. If the outer level
991 /// of the type is already concrete, it returns it unmodified.
992 QualType getSingleStepDesugaredType(const ASTContext &Context) const {
993 return getSingleStepDesugaredTypeImpl(*this, Context);
994 }
995
996 /// Returns the specified type after dropping any
997 /// outer-level parentheses.
998 QualType IgnoreParens() const {
999 if (isa<ParenType>(*this))
1000 return QualType::IgnoreParens(*this);
1001 return *this;
1002 }
1003
1004 /// Indicate whether the specified types and qualifiers are identical.
1005 friend bool operator==(const QualType &LHS, const QualType &RHS) {
1006 return LHS.Value == RHS.Value;
1007 }
1008 friend bool operator!=(const QualType &LHS, const QualType &RHS) {
1009 return LHS.Value != RHS.Value;
1010 }
1011 friend bool operator<(const QualType &LHS, const QualType &RHS) {
1012 return LHS.Value < RHS.Value;
1013 }
1014
1015 static std::string getAsString(SplitQualType split,
1016 const PrintingPolicy &Policy) {
1017 return getAsString(split.Ty, split.Quals, Policy);
1018 }
1019 static std::string getAsString(const Type *ty, Qualifiers qs,
1020 const PrintingPolicy &Policy);
1021
1022 std::string getAsString() const;
1023 std::string getAsString(const PrintingPolicy &Policy) const;
1024
1025 void print(raw_ostream &OS, const PrintingPolicy &Policy,
1026 const Twine &PlaceHolder = Twine(),
1027 unsigned Indentation = 0) const;
1028
1029 static void print(SplitQualType split, raw_ostream &OS,
1030 const PrintingPolicy &policy, const Twine &PlaceHolder,
1031 unsigned Indentation = 0) {
1032 return print(split.Ty, split.Quals, OS, policy, PlaceHolder, Indentation);
1033 }
1034
1035 static void print(const Type *ty, Qualifiers qs,
1036 raw_ostream &OS, const PrintingPolicy &policy,
1037 const Twine &PlaceHolder,
1038 unsigned Indentation = 0);
1039
1040 void getAsStringInternal(std::string &Str,
1041 const PrintingPolicy &Policy) const;
1042
1043 static void getAsStringInternal(SplitQualType split, std::string &out,
1044 const PrintingPolicy &policy) {
1045 return getAsStringInternal(split.Ty, split.Quals, out, policy);
1046 }
1047
1048 static void getAsStringInternal(const Type *ty, Qualifiers qs,
1049 std::string &out,
1050 const PrintingPolicy &policy);
1051
1052 class StreamedQualTypeHelper {
1053 const QualType &T;
1054 const PrintingPolicy &Policy;
1055 const Twine &PlaceHolder;
1056 unsigned Indentation;
1057
1058 public:
1059 StreamedQualTypeHelper(const QualType &T, const PrintingPolicy &Policy,
1060 const Twine &PlaceHolder, unsigned Indentation)
1061 : T(T), Policy(Policy), PlaceHolder(PlaceHolder),
1062 Indentation(Indentation) {}
1063
1064 friend raw_ostream &operator<<(raw_ostream &OS,
1065 const StreamedQualTypeHelper &SQT) {
1066 SQT.T.print(OS, SQT.Policy, SQT.PlaceHolder, SQT.Indentation);
1067 return OS;
1068 }
1069 };
1070
1071 StreamedQualTypeHelper stream(const PrintingPolicy &Policy,
1072 const Twine &PlaceHolder = Twine(),
1073 unsigned Indentation = 0) const {
1074 return StreamedQualTypeHelper(*this, Policy, PlaceHolder, Indentation);
1075 }
1076
1077 void dump(const char *s) const;
1078 void dump() const;
1079 void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
1080
1081 void Profile(llvm::FoldingSetNodeID &ID) const {
1082 ID.AddPointer(getAsOpaquePtr());
1083 }
1084
1085 /// Check if this type has any address space qualifier.
1086 inline bool hasAddressSpace() const;
1087
1088 /// Return the address space of this type.
1089 inline LangAS getAddressSpace() const;
1090
1091 /// Returns true if address space qualifiers overlap with T address space
1092 /// qualifiers.
1093 /// OpenCL C defines conversion rules for pointers to different address spaces
1094 /// and notion of overlapping address spaces.
1095 /// CL1.1 or CL1.2:
1096 /// address spaces overlap iff they are they same.
1097 /// OpenCL C v2.0 s6.5.5 adds:
1098 /// __generic overlaps with any address space except for __constant.
1099 bool isAddressSpaceOverlapping(QualType T) const {
1100 Qualifiers Q = getQualifiers();
1101 Qualifiers TQ = T.getQualifiers();
1102 // Address spaces overlap if at least one of them is a superset of another
1103 return Q.isAddressSpaceSupersetOf(TQ) || TQ.isAddressSpaceSupersetOf(Q);
1104 }
1105
1106 /// Returns gc attribute of this type.
1107 inline Qualifiers::GC getObjCGCAttr() const;
1108
1109 /// true when Type is objc's weak.
1110 bool isObjCGCWeak() const {
1111 return getObjCGCAttr() == Qualifiers::Weak;
1112 }
1113
1114 /// true when Type is objc's strong.
1115 bool isObjCGCStrong() const {
1116 return getObjCGCAttr() == Qualifiers::Strong;
1117 }
1118
1119 /// Returns lifetime attribute of this type.
1120 Qualifiers::ObjCLifetime getObjCLifetime() const {
1121 return getQualifiers().getObjCLifetime();
1122 }
1123
1124 bool hasNonTrivialObjCLifetime() const {
1125 return getQualifiers().hasNonTrivialObjCLifetime();
1126 }
1127
1128 bool hasStrongOrWeakObjCLifetime() const {
1129 return getQualifiers().hasStrongOrWeakObjCLifetime();
1130 }
1131
1132 // true when Type is objc's weak and weak is enabled but ARC isn't.
1133 bool isNonWeakInMRRWithObjCWeak(const ASTContext &Context) const;
1134
1135 enum PrimitiveDefaultInitializeKind {
1136 /// The type does not fall into any of the following categories. Note that
1137 /// this case is zero-valued so that values of this enum can be used as a
1138 /// boolean condition for non-triviality.
1139 PDIK_Trivial,
1140
1141 /// The type is an Objective-C retainable pointer type that is qualified
1142 /// with the ARC __strong qualifier.
1143 PDIK_ARCStrong,
1144
1145 /// The type is an Objective-C retainable pointer type that is qualified
1146 /// with the ARC __weak qualifier.
1147 PDIK_ARCWeak,
1148
1149 /// The type is a struct containing a field whose type is not PCK_Trivial.
1150 PDIK_Struct
1151 };
1152
1153 /// Functions to query basic properties of non-trivial C struct types.
1154
1155 /// Check if this is a non-trivial type that would cause a C struct
1156 /// transitively containing this type to be non-trivial to default initialize
1157 /// and return the kind.
1158 PrimitiveDefaultInitializeKind
1159 isNonTrivialToPrimitiveDefaultInitialize() const;
1160
1161 enum PrimitiveCopyKind {
1162 /// The type does not fall into any of the following categories. Note that
1163 /// this case is zero-valued so that values of this enum can be used as a
1164 /// boolean condition for non-triviality.
1165 PCK_Trivial,
1166
1167 /// The type would be trivial except that it is volatile-qualified. Types
1168 /// that fall into one of the other non-trivial cases may additionally be
1169 /// volatile-qualified.
1170 PCK_VolatileTrivial,
1171
1172 /// The type is an Objective-C retainable pointer type that is qualified
1173 /// with the ARC __strong qualifier.
1174 PCK_ARCStrong,
1175
1176 /// The type is an Objective-C retainable pointer type that is qualified
1177 /// with the ARC __weak qualifier.
1178 PCK_ARCWeak,
1179
1180 /// The type is a struct containing a field whose type is neither
1181 /// PCK_Trivial nor PCK_VolatileTrivial.
1182 /// Note that a C++ struct type does not necessarily match this; C++ copying
1183 /// semantics are too complex to express here, in part because they depend
1184 /// on the exact constructor or assignment operator that is chosen by
1185 /// overload resolution to do the copy.
1186 PCK_Struct
1187 };
1188
1189 /// Check if this is a non-trivial type that would cause a C struct
1190 /// transitively containing this type to be non-trivial to copy and return the
1191 /// kind.
1192 PrimitiveCopyKind isNonTrivialToPrimitiveCopy() const;
1193
1194 /// Check if this is a non-trivial type that would cause a C struct
1195 /// transitively containing this type to be non-trivial to destructively
1196 /// move and return the kind. Destructive move in this context is a C++-style
1197 /// move in which the source object is placed in a valid but unspecified state
1198 /// after it is moved, as opposed to a truly destructive move in which the
1199 /// source object is placed in an uninitialized state.
1200 PrimitiveCopyKind isNonTrivialToPrimitiveDestructiveMove() const;
1201
1202 enum DestructionKind {
1203 DK_none,
1204 DK_cxx_destructor,
1205 DK_objc_strong_lifetime,
1206 DK_objc_weak_lifetime,
1207 DK_nontrivial_c_struct
1208 };
1209
1210 /// Returns a nonzero value if objects of this type require
1211 /// non-trivial work to clean up after. Non-zero because it's
1212 /// conceivable that qualifiers (objc_gc(weak)?) could make
1213 /// something require destruction.
1214 DestructionKind isDestructedType() const {
1215 return isDestructedTypeImpl(*this);
1216 }
1217
1218 /// Check if this is or contains a C union that is non-trivial to
1219 /// default-initialize, which is a union that has a member that is non-trivial
1220 /// to default-initialize. If this returns true,
1221 /// isNonTrivialToPrimitiveDefaultInitialize returns PDIK_Struct.
1222 bool hasNonTrivialToPrimitiveDefaultInitializeCUnion() const;
1223
1224 /// Check if this is or contains a C union that is non-trivial to destruct,
1225 /// which is a union that has a member that is non-trivial to destruct. If
1226 /// this returns true, isDestructedType returns DK_nontrivial_c_struct.
1227 bool hasNonTrivialToPrimitiveDestructCUnion() const;
1228
1229 /// Check if this is or contains a C union that is non-trivial to copy, which
1230 /// is a union that has a member that is non-trivial to copy. If this returns
1231 /// true, isNonTrivialToPrimitiveCopy returns PCK_Struct.
1232 bool hasNonTrivialToPrimitiveCopyCUnion() const;
1233
1234 /// Determine whether expressions of the given type are forbidden
1235 /// from being lvalues in C.
1236 ///
1237 /// The expression types that are forbidden to be lvalues are:
1238 /// - 'void', but not qualified void
1239 /// - function types
1240 ///
1241 /// The exact rule here is C99 6.3.2.1:
1242 /// An lvalue is an expression with an object type or an incomplete
1243 /// type other than void.
1244 bool isCForbiddenLValueType() const;
1245
1246 /// Substitute type arguments for the Objective-C type parameters used in the
1247 /// subject type.
1248 ///
1249 /// \param ctx ASTContext in which the type exists.
1250 ///
1251 /// \param typeArgs The type arguments that will be substituted for the
1252 /// Objective-C type parameters in the subject type, which are generally
1253 /// computed via \c Type::getObjCSubstitutions. If empty, the type
1254 /// parameters will be replaced with their bounds or id/Class, as appropriate
1255 /// for the context.
1256 ///
1257 /// \param context The context in which the subject type was written.
1258 ///
1259 /// \returns the resulting type.
1260 QualType substObjCTypeArgs(ASTContext &ctx,
1261 ArrayRef<QualType> typeArgs,
1262 ObjCSubstitutionContext context) const;
1263
1264 /// Substitute type arguments from an object type for the Objective-C type
1265 /// parameters used in the subject type.
1266 ///
1267 /// This operation combines the computation of type arguments for
1268 /// substitution (\c Type::getObjCSubstitutions) with the actual process of
1269 /// substitution (\c QualType::substObjCTypeArgs) for the convenience of
1270 /// callers that need to perform a single substitution in isolation.
1271 ///
1272 /// \param objectType The type of the object whose member type we're
1273 /// substituting into. For example, this might be the receiver of a message
1274 /// or the base of a property access.
1275 ///
1276 /// \param dc The declaration context from which the subject type was
1277 /// retrieved, which indicates (for example) which type parameters should
1278 /// be substituted.
1279 ///
1280 /// \param context The context in which the subject type was written.
1281 ///
1282 /// \returns the subject type after replacing all of the Objective-C type
1283 /// parameters with their corresponding arguments.
1284 QualType substObjCMemberType(QualType objectType,
1285 const DeclContext *dc,
1286 ObjCSubstitutionContext context) const;
1287
1288 /// Strip Objective-C "__kindof" types from the given type.
1289 QualType stripObjCKindOfType(const ASTContext &ctx) const;
1290
1291 /// Remove all qualifiers including _Atomic.
1292 QualType getAtomicUnqualifiedType() const;
1293
1294private:
1295 // These methods are implemented in a separate translation unit;
1296 // "static"-ize them to avoid creating temporary QualTypes in the
1297 // caller.
1298 static bool isConstant(QualType T, const ASTContext& Ctx);
1299 static QualType getDesugaredType(QualType T, const ASTContext &Context);
1300 static SplitQualType getSplitDesugaredType(QualType T);
1301 static SplitQualType getSplitUnqualifiedTypeImpl(QualType type);
1302 static QualType getSingleStepDesugaredTypeImpl(QualType type,
1303 const ASTContext &C);
1304 static QualType IgnoreParens(QualType T);
1305 static DestructionKind isDestructedTypeImpl(QualType type);
1306
1307 /// Check if \param RD is or contains a non-trivial C union.
1308 static bool hasNonTrivialToPrimitiveDefaultInitializeCUnion(const RecordDecl *RD);
1309 static bool hasNonTrivialToPrimitiveDestructCUnion(const RecordDecl *RD);
1310 static bool hasNonTrivialToPrimitiveCopyCUnion(const RecordDecl *RD);
1311};
1312
1313} // namespace clang
1314
1315namespace llvm {
1316
1317/// Implement simplify_type for QualType, so that we can dyn_cast from QualType
1318/// to a specific Type class.
1319template<> struct simplify_type< ::clang::QualType> {
1320 using SimpleType = const ::clang::Type *;
1321
1322 static SimpleType getSimplifiedValue(::clang::QualType Val) {
1323 return Val.getTypePtr();
1324 }
1325};
1326
1327// Teach SmallPtrSet that QualType is "basically a pointer".
1328template<>
1329struct PointerLikeTypeTraits<clang::QualType> {
1330 static inline void *getAsVoidPointer(clang::QualType P) {
1331 return P.getAsOpaquePtr();
1332 }
1333
1334 static inline clang::QualType getFromVoidPointer(void *P) {
1335 return clang::QualType::getFromOpaquePtr(P);
1336 }
1337
1338 // Various qualifiers go in low bits.
1339 static constexpr int NumLowBitsAvailable = 0;
1340};
1341
1342} // namespace llvm
1343
1344namespace clang {
1345
1346/// Base class that is common to both the \c ExtQuals and \c Type
1347/// classes, which allows \c QualType to access the common fields between the
1348/// two.
1349class ExtQualsTypeCommonBase {
1350 friend class ExtQuals;
1351 friend class QualType;
1352 friend class Type;
1353
1354 /// The "base" type of an extended qualifiers type (\c ExtQuals) or
1355 /// a self-referential pointer (for \c Type).
1356 ///
1357 /// This pointer allows an efficient mapping from a QualType to its
1358 /// underlying type pointer.
1359 const Type *const BaseType;
1360
1361 /// The canonical type of this type. A QualType.
1362 QualType CanonicalType;
1363
1364 ExtQualsTypeCommonBase(const Type *baseType, QualType canon)
1365 : BaseType(baseType), CanonicalType(canon) {}
1366};
1367
1368/// We can encode up to four bits in the low bits of a
1369/// type pointer, but there are many more type qualifiers that we want
1370/// to be able to apply to an arbitrary type. Therefore we have this
1371/// struct, intended to be heap-allocated and used by QualType to
1372/// store qualifiers.
1373///
1374/// The current design tags the 'const', 'restrict', and 'volatile' qualifiers
1375/// in three low bits on the QualType pointer; a fourth bit records whether
1376/// the pointer is an ExtQuals node. The extended qualifiers (address spaces,
1377/// Objective-C GC attributes) are much more rare.
1378class ExtQuals : public ExtQualsTypeCommonBase, public llvm::FoldingSetNode {
1379 // NOTE: changing the fast qualifiers should be straightforward as
1380 // long as you don't make 'const' non-fast.
1381 // 1. Qualifiers:
1382 // a) Modify the bitmasks (Qualifiers::TQ and DeclSpec::TQ).
1383 // Fast qualifiers must occupy the low-order bits.
1384 // b) Update Qualifiers::FastWidth and FastMask.
1385 // 2. QualType:
1386 // a) Update is{Volatile,Restrict}Qualified(), defined inline.
1387 // b) Update remove{Volatile,Restrict}, defined near the end of
1388 // this header.
1389 // 3. ASTContext:
1390 // a) Update get{Volatile,Restrict}Type.
1391
1392 /// The immutable set of qualifiers applied by this node. Always contains
1393 /// extended qualifiers.
1394 Qualifiers Quals;
1395
1396 ExtQuals *this_() { return this; }
1397
1398public:
1399 ExtQuals(const Type *baseType, QualType canon, Qualifiers quals)
1400 : ExtQualsTypeCommonBase(baseType,
1401 canon.isNull() ? QualType(this_(), 0) : canon),
1402 Quals(quals) {
1403 assert(Quals.hasNonFastQualifiers()(static_cast<void> (0))
1404 && "ExtQuals created with no fast qualifiers")(static_cast<void> (0));
1405 assert(!Quals.hasFastQualifiers()(static_cast<void> (0))
1406 && "ExtQuals created with fast qualifiers")(static_cast<void> (0));
1407 }
1408
1409 Qualifiers getQualifiers() const { return Quals; }
1410
1411 bool hasObjCGCAttr() const { return Quals.hasObjCGCAttr(); }
1412 Qualifiers::GC getObjCGCAttr() const { return Quals.getObjCGCAttr(); }
1413
1414 bool hasObjCLifetime() const { return Quals.hasObjCLifetime(); }
1415 Qualifiers::ObjCLifetime getObjCLifetime() const {
1416 return Quals.getObjCLifetime();
1417 }
1418
1419 bool hasAddressSpace() const { return Quals.hasAddressSpace(); }
1420 LangAS getAddressSpace() const { return Quals.getAddressSpace(); }
1421
1422 const Type *getBaseType() const { return BaseType; }
1423
1424public:
1425 void Profile(llvm::FoldingSetNodeID &ID) const {
1426 Profile(ID, getBaseType(), Quals);
1427 }
1428
1429 static void Profile(llvm::FoldingSetNodeID &ID,
1430 const Type *BaseType,
1431 Qualifiers Quals) {
1432 assert(!Quals.hasFastQualifiers() && "fast qualifiers in ExtQuals hash!")(static_cast<void> (0));
1433 ID.AddPointer(BaseType);
1434 Quals.Profile(ID);
1435 }
1436};
1437
1438/// The kind of C++11 ref-qualifier associated with a function type.
1439/// This determines whether a member function's "this" object can be an
1440/// lvalue, rvalue, or neither.
1441enum RefQualifierKind {
1442 /// No ref-qualifier was provided.
1443 RQ_None = 0,
1444
1445 /// An lvalue ref-qualifier was provided (\c &).
1446 RQ_LValue,
1447
1448 /// An rvalue ref-qualifier was provided (\c &&).
1449 RQ_RValue
1450};
1451
1452/// Which keyword(s) were used to create an AutoType.
1453enum class AutoTypeKeyword {
1454 /// auto
1455 Auto,
1456
1457 /// decltype(auto)
1458 DecltypeAuto,
1459
1460 /// __auto_type (GNU extension)
1461 GNUAutoType
1462};
1463
1464/// The base class of the type hierarchy.
1465///
1466/// A central concept with types is that each type always has a canonical
1467/// type. A canonical type is the type with any typedef names stripped out
1468/// of it or the types it references. For example, consider:
1469///
1470/// typedef int foo;
1471/// typedef foo* bar;
1472/// 'int *' 'foo *' 'bar'
1473///
1474/// There will be a Type object created for 'int'. Since int is canonical, its
1475/// CanonicalType pointer points to itself. There is also a Type for 'foo' (a
1476/// TypedefType). Its CanonicalType pointer points to the 'int' Type. Next
1477/// there is a PointerType that represents 'int*', which, like 'int', is
1478/// canonical. Finally, there is a PointerType type for 'foo*' whose canonical
1479/// type is 'int*', and there is a TypedefType for 'bar', whose canonical type
1480/// is also 'int*'.
1481///
1482/// Non-canonical types are useful for emitting diagnostics, without losing
1483/// information about typedefs being used. Canonical types are useful for type
1484/// comparisons (they allow by-pointer equality tests) and useful for reasoning
1485/// about whether something has a particular form (e.g. is a function type),
1486/// because they implicitly, recursively, strip all typedefs out of a type.
1487///
1488/// Types, once created, are immutable.
1489///
1490class alignas(8) Type : public ExtQualsTypeCommonBase {
1491public:
1492 enum TypeClass {
1493#define TYPE(Class, Base) Class,
1494#define LAST_TYPE(Class) TypeLast = Class
1495#define ABSTRACT_TYPE(Class, Base)
1496#include "clang/AST/TypeNodes.inc"
1497 };
1498
1499private:
1500 /// Bitfields required by the Type class.
1501 class TypeBitfields {
1502 friend class Type;
1503 template <class T> friend class TypePropertyCache;
1504
1505 /// TypeClass bitfield - Enum that specifies what subclass this belongs to.
1506 unsigned TC : 8;
1507
1508 /// Store information on the type dependency.
1509 unsigned Dependence : llvm::BitWidth<TypeDependence>;
1510
1511 /// True if the cache (i.e. the bitfields here starting with
1512 /// 'Cache') is valid.
1513 mutable unsigned CacheValid : 1;
1514
1515 /// Linkage of this type.
1516 mutable unsigned CachedLinkage : 3;
1517
1518 /// Whether this type involves and local or unnamed types.
1519 mutable unsigned CachedLocalOrUnnamed : 1;
1520
1521 /// Whether this type comes from an AST file.
1522 mutable unsigned FromAST : 1;
1523
1524 bool isCacheValid() const {
1525 return CacheValid;
1526 }
1527
1528 Linkage getLinkage() const {
1529 assert(isCacheValid() && "getting linkage from invalid cache")(static_cast<void> (0));
1530 return static_cast<Linkage>(CachedLinkage);
1531 }
1532
1533 bool hasLocalOrUnnamedType() const {
1534 assert(isCacheValid() && "getting linkage from invalid cache")(static_cast<void> (0));
1535 return CachedLocalOrUnnamed;
1536 }
1537 };
1538 enum { NumTypeBits = 8 + llvm::BitWidth<TypeDependence> + 6 };
1539
1540protected:
1541 // These classes allow subclasses to somewhat cleanly pack bitfields
1542 // into Type.
1543
1544 class ArrayTypeBitfields {
1545 friend class ArrayType;
1546
1547 unsigned : NumTypeBits;
1548
1549 /// CVR qualifiers from declarations like
1550 /// 'int X[static restrict 4]'. For function parameters only.
1551 unsigned IndexTypeQuals : 3;
1552
1553 /// Storage class qualifiers from declarations like
1554 /// 'int X[static restrict 4]'. For function parameters only.
1555 /// Actually an ArrayType::ArraySizeModifier.
1556 unsigned SizeModifier : 3;
1557 };
1558
1559 class ConstantArrayTypeBitfields {
1560 friend class ConstantArrayType;
1561
1562 unsigned : NumTypeBits + 3 + 3;
1563
1564 /// Whether we have a stored size expression.
1565 unsigned HasStoredSizeExpr : 1;
1566 };
1567
1568 class BuiltinTypeBitfields {
1569 friend class BuiltinType;
1570
1571 unsigned : NumTypeBits;
1572
1573 /// The kind (BuiltinType::Kind) of builtin type this is.
1574 unsigned Kind : 8;
1575 };
1576
1577 /// FunctionTypeBitfields store various bits belonging to FunctionProtoType.
1578 /// Only common bits are stored here. Additional uncommon bits are stored
1579 /// in a trailing object after FunctionProtoType.
1580 class FunctionTypeBitfields {
1581 friend class FunctionProtoType;
1582 friend class FunctionType;
1583
1584 unsigned : NumTypeBits;
1585
1586 /// Extra information which affects how the function is called, like
1587 /// regparm and the calling convention.
1588 unsigned ExtInfo : 13;
1589
1590 /// The ref-qualifier associated with a \c FunctionProtoType.
1591 ///
1592 /// This is a value of type \c RefQualifierKind.
1593 unsigned RefQualifier : 2;
1594
1595 /// Used only by FunctionProtoType, put here to pack with the
1596 /// other bitfields.
1597 /// The qualifiers are part of FunctionProtoType because...
1598 ///
1599 /// C++ 8.3.5p4: The return type, the parameter type list and the
1600 /// cv-qualifier-seq, [...], are part of the function type.
1601 unsigned FastTypeQuals : Qualifiers::FastWidth;
1602 /// Whether this function has extended Qualifiers.
1603 unsigned HasExtQuals : 1;
1604
1605 /// The number of parameters this function has, not counting '...'.
1606 /// According to [implimits] 8 bits should be enough here but this is
1607 /// somewhat easy to exceed with metaprogramming and so we would like to
1608 /// keep NumParams as wide as reasonably possible.
1609 unsigned NumParams : 16;
1610
1611 /// The type of exception specification this function has.
1612 unsigned ExceptionSpecType : 4;
1613
1614 /// Whether this function has extended parameter information.
1615 unsigned HasExtParameterInfos : 1;
1616
1617 /// Whether the function is variadic.
1618 unsigned Variadic : 1;
1619
1620 /// Whether this function has a trailing return type.
1621 unsigned HasTrailingReturn : 1;
1622 };
1623
1624 class ObjCObjectTypeBitfields {
1625 friend class ObjCObjectType;
1626
1627 unsigned : NumTypeBits;
1628
1629 /// The number of type arguments stored directly on this object type.
1630 unsigned NumTypeArgs : 7;
1631
1632 /// The number of protocols stored directly on this object type.
1633 unsigned NumProtocols : 6;
1634
1635 /// Whether this is a "kindof" type.
1636 unsigned IsKindOf : 1;
1637 };
1638
1639 class ReferenceTypeBitfields {
1640 friend class ReferenceType;
1641
1642 unsigned : NumTypeBits;
1643
1644 /// True if the type was originally spelled with an lvalue sigil.
1645 /// This is never true of rvalue references but can also be false
1646 /// on lvalue references because of C++0x [dcl.typedef]p9,
1647 /// as follows:
1648 ///
1649 /// typedef int &ref; // lvalue, spelled lvalue
1650 /// typedef int &&rvref; // rvalue
1651 /// ref &a; // lvalue, inner ref, spelled lvalue
1652 /// ref &&a; // lvalue, inner ref
1653 /// rvref &a; // lvalue, inner ref, spelled lvalue
1654 /// rvref &&a; // rvalue, inner ref
1655 unsigned SpelledAsLValue : 1;
1656
1657 /// True if the inner type is a reference type. This only happens
1658 /// in non-canonical forms.
1659 unsigned InnerRef : 1;
1660 };
1661
1662 class TypeWithKeywordBitfields {
1663 friend class TypeWithKeyword;
1664
1665 unsigned : NumTypeBits;
1666
1667 /// An ElaboratedTypeKeyword. 8 bits for efficient access.
1668 unsigned Keyword : 8;
1669 };
1670
1671 enum { NumTypeWithKeywordBits = 8 };
1672
1673 class ElaboratedTypeBitfields {
1674 friend class ElaboratedType;
1675
1676 unsigned : NumTypeBits;
1677 unsigned : NumTypeWithKeywordBits;
1678
1679 /// Whether the ElaboratedType has a trailing OwnedTagDecl.
1680 unsigned HasOwnedTagDecl : 1;
1681 };
1682
1683 class VectorTypeBitfields {
1684 friend class VectorType;
1685 friend class DependentVectorType;
1686
1687 unsigned : NumTypeBits;
1688
1689 /// The kind of vector, either a generic vector type or some
1690 /// target-specific vector type such as for AltiVec or Neon.
1691 unsigned VecKind : 3;
1692 /// The number of elements in the vector.
1693 uint32_t NumElements;
1694 };
1695
1696 class AttributedTypeBitfields {
1697 friend class AttributedType;
1698
1699 unsigned : NumTypeBits;
1700
1701 /// An AttributedType::Kind
1702 unsigned AttrKind : 32 - NumTypeBits;
1703 };
1704
1705 class AutoTypeBitfields {
1706 friend class AutoType;
1707
1708 unsigned : NumTypeBits;
1709
1710 /// Was this placeholder type spelled as 'auto', 'decltype(auto)',
1711 /// or '__auto_type'? AutoTypeKeyword value.
1712 unsigned Keyword : 2;
1713
1714 /// The number of template arguments in the type-constraints, which is
1715 /// expected to be able to hold at least 1024 according to [implimits].
1716 /// However as this limit is somewhat easy to hit with template
1717 /// metaprogramming we'd prefer to keep it as large as possible.
1718 /// At the moment it has been left as a non-bitfield since this type
1719 /// safely fits in 64 bits as an unsigned, so there is no reason to
1720 /// introduce the performance impact of a bitfield.
1721 unsigned NumArgs;
1722 };
1723
1724 class SubstTemplateTypeParmPackTypeBitfields {
1725 friend class SubstTemplateTypeParmPackType;
1726
1727 unsigned : NumTypeBits;
1728
1729 /// The number of template arguments in \c Arguments, which is
1730 /// expected to be able to hold at least 1024 according to [implimits].
1731 /// However as this limit is somewhat easy to hit with template
1732 /// metaprogramming we'd prefer to keep it as large as possible.
1733 /// At the moment it has been left as a non-bitfield since this type
1734 /// safely fits in 64 bits as an unsigned, so there is no reason to
1735 /// introduce the performance impact of a bitfield.
1736 unsigned NumArgs;
1737 };
1738
1739 class TemplateSpecializationTypeBitfields {
1740 friend class TemplateSpecializationType;
1741
1742 unsigned : NumTypeBits;
1743
1744 /// Whether this template specialization type is a substituted type alias.
1745 unsigned TypeAlias : 1;
1746
1747 /// The number of template arguments named in this class template
1748 /// specialization, which is expected to be able to hold at least 1024
1749 /// according to [implimits]. However, as this limit is somewhat easy to
1750 /// hit with template metaprogramming we'd prefer to keep it as large
1751 /// as possible. At the moment it has been left as a non-bitfield since
1752 /// this type safely fits in 64 bits as an unsigned, so there is no reason
1753 /// to introduce the performance impact of a bitfield.
1754 unsigned NumArgs;
1755 };
1756
1757 class DependentTemplateSpecializationTypeBitfields {
1758 friend class DependentTemplateSpecializationType;
1759
1760 unsigned : NumTypeBits;
1761 unsigned : NumTypeWithKeywordBits;
1762
1763 /// The number of template arguments named in this class template
1764 /// specialization, which is expected to be able to hold at least 1024
1765 /// according to [implimits]. However, as this limit is somewhat easy to
1766 /// hit with template metaprogramming we'd prefer to keep it as large
1767 /// as possible. At the moment it has been left as a non-bitfield since
1768 /// this type safely fits in 64 bits as an unsigned, so there is no reason
1769 /// to introduce the performance impact of a bitfield.
1770 unsigned NumArgs;
1771 };
1772
1773 class PackExpansionTypeBitfields {
1774 friend class PackExpansionType;
1775
1776 unsigned : NumTypeBits;
1777
1778 /// The number of expansions that this pack expansion will
1779 /// generate when substituted (+1), which is expected to be able to
1780 /// hold at least 1024 according to [implimits]. However, as this limit
1781 /// is somewhat easy to hit with template metaprogramming we'd prefer to
1782 /// keep it as large as possible. At the moment it has been left as a
1783 /// non-bitfield since this type safely fits in 64 bits as an unsigned, so
1784 /// there is no reason to introduce the performance impact of a bitfield.
1785 ///
1786 /// This field will only have a non-zero value when some of the parameter
1787 /// packs that occur within the pattern have been substituted but others
1788 /// have not.
1789 unsigned NumExpansions;
1790 };
1791
1792 union {
1793 TypeBitfields TypeBits;
1794 ArrayTypeBitfields ArrayTypeBits;
1795 ConstantArrayTypeBitfields ConstantArrayTypeBits;
1796 AttributedTypeBitfields AttributedTypeBits;
1797 AutoTypeBitfields AutoTypeBits;
1798 BuiltinTypeBitfields BuiltinTypeBits;
1799 FunctionTypeBitfields FunctionTypeBits;
1800 ObjCObjectTypeBitfields ObjCObjectTypeBits;
1801 ReferenceTypeBitfields ReferenceTypeBits;
1802 TypeWithKeywordBitfields TypeWithKeywordBits;
1803 ElaboratedTypeBitfields ElaboratedTypeBits;
1804 VectorTypeBitfields VectorTypeBits;
1805 SubstTemplateTypeParmPackTypeBitfields SubstTemplateTypeParmPackTypeBits;
1806 TemplateSpecializationTypeBitfields TemplateSpecializationTypeBits;
1807 DependentTemplateSpecializationTypeBitfields
1808 DependentTemplateSpecializationTypeBits;
1809 PackExpansionTypeBitfields PackExpansionTypeBits;
1810 };
1811
1812private:
1813 template <class T> friend class TypePropertyCache;
1814
1815 /// Set whether this type comes from an AST file.
1816 void setFromAST(bool V = true) const {
1817 TypeBits.FromAST = V;
1818 }
1819
1820protected:
1821 friend class ASTContext;
1822
1823 Type(TypeClass tc, QualType canon, TypeDependence Dependence)
1824 : ExtQualsTypeCommonBase(this,
1825 canon.isNull() ? QualType(this_(), 0) : canon) {
1826 static_assert(sizeof(*this) <= 8 + sizeof(ExtQualsTypeCommonBase),
1827 "changing bitfields changed sizeof(Type)!");
1828 static_assert(alignof(decltype(*this)) % sizeof(void *) == 0,
1829 "Insufficient alignment!");
1830 TypeBits.TC = tc;
1831 TypeBits.Dependence = static_cast<unsigned>(Dependence);
1832 TypeBits.CacheValid = false;
1833 TypeBits.CachedLocalOrUnnamed = false;
1834 TypeBits.CachedLinkage = NoLinkage;
1835 TypeBits.FromAST = false;
1836 }
1837
1838 // silence VC++ warning C4355: 'this' : used in base member initializer list
1839 Type *this_() { return this; }
1840
1841 void setDependence(TypeDependence D) {
1842 TypeBits.Dependence = static_cast<unsigned>(D);
1843 }
1844
1845 void addDependence(TypeDependence D) { setDependence(getDependence() | D); }
1846
1847public:
1848 friend class ASTReader;
1849 friend class ASTWriter;
1850 template <class T> friend class serialization::AbstractTypeReader;
1851 template <class T> friend class serialization::AbstractTypeWriter;
1852
1853 Type(const Type &) = delete;
1854 Type(Type &&) = delete;
1855 Type &operator=(const Type &) = delete;
1856 Type &operator=(Type &&) = delete;
1857
1858 TypeClass getTypeClass() const { return static_cast<TypeClass>(TypeBits.TC); }
1859
1860 /// Whether this type comes from an AST file.
1861 bool isFromAST() const { return TypeBits.FromAST; }
1862
1863 /// Whether this type is or contains an unexpanded parameter
1864 /// pack, used to support C++0x variadic templates.
1865 ///
1866 /// A type that contains a parameter pack shall be expanded by the
1867 /// ellipsis operator at some point. For example, the typedef in the
1868 /// following example contains an unexpanded parameter pack 'T':
1869 ///
1870 /// \code
1871 /// template<typename ...T>
1872 /// struct X {
1873 /// typedef T* pointer_types; // ill-formed; T is a parameter pack.
1874 /// };
1875 /// \endcode
1876 ///
1877 /// Note that this routine does not specify which
1878 bool containsUnexpandedParameterPack() const {
1879 return getDependence() & TypeDependence::UnexpandedPack;
1880 }
1881
1882 /// Determines if this type would be canonical if it had no further
1883 /// qualification.
1884 bool isCanonicalUnqualified() const {
1885 return CanonicalType == QualType(this, 0);
1886 }
1887
1888 /// Pull a single level of sugar off of this locally-unqualified type.
1889 /// Users should generally prefer SplitQualType::getSingleStepDesugaredType()
1890 /// or QualType::getSingleStepDesugaredType(const ASTContext&).
1891 QualType getLocallyUnqualifiedSingleStepDesugaredType() const;
1892
1893 /// As an extension, we classify types as one of "sized" or "sizeless";
1894 /// every type is one or the other. Standard types are all sized;
1895 /// sizeless types are purely an extension.
1896 ///
1897 /// Sizeless types contain data with no specified size, alignment,
1898 /// or layout.
1899 bool isSizelessType() const;
1900 bool isSizelessBuiltinType() const;
1901
1902 /// Determines if this is a sizeless type supported by the
1903 /// 'arm_sve_vector_bits' type attribute, which can be applied to a single
1904 /// SVE vector or predicate, excluding tuple types such as svint32x4_t.
1905 bool isVLSTBuiltinType() const;
1906
1907 /// Returns the representative type for the element of an SVE builtin type.
1908 /// This is used to represent fixed-length SVE vectors created with the
1909 /// 'arm_sve_vector_bits' type attribute as VectorType.
1910 QualType getSveEltType(const ASTContext &Ctx) const;
1911
1912 /// Types are partitioned into 3 broad categories (C99 6.2.5p1):
1913 /// object types, function types, and incomplete types.
1914
1915 /// Return true if this is an incomplete type.
1916 /// A type that can describe objects, but which lacks information needed to
1917 /// determine its size (e.g. void, or a fwd declared struct). Clients of this
1918 /// routine will need to determine if the size is actually required.
1919 ///
1920 /// Def If non-null, and the type refers to some kind of declaration
1921 /// that can be completed (such as a C struct, C++ class, or Objective-C
1922 /// class), will be set to the declaration.
1923 bool isIncompleteType(NamedDecl **Def = nullptr) const;
1924
1925 /// Return true if this is an incomplete or object
1926 /// type, in other words, not a function type.
1927 bool isIncompleteOrObjectType() const {
1928 return !isFunctionType();
1929 }
1930