clang 8.0.0

CodeGenTypes.h
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1 //===--- CodeGenTypes.h - Type translation for LLVM CodeGen -----*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This is the code that handles AST -> LLVM type lowering.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #ifndef LLVM_CLANG_LIB_CODEGEN_CODEGENTYPES_H
15 #define LLVM_CLANG_LIB_CODEGEN_CODEGENTYPES_H
16
17 #include "CGCall.h"
18 #include "clang/Basic/ABI.h"
19 #include "clang/CodeGen/CGFunctionInfo.h"
20 #include "llvm/ADT/DenseMap.h"
21 #include "llvm/IR/Module.h"
22
23 namespace llvm {
24 class FunctionType;
25 class DataLayout;
26 class Type;
27 class LLVMContext;
28 class StructType;
29 }
30
31 namespace clang {
32 class ASTContext;
33 template <typename> class CanQual;
34 class CXXConstructorDecl;
35 class CXXDestructorDecl;
36 class CXXMethodDecl;
37 class CodeGenOptions;
38 class FieldDecl;
39 class FunctionProtoType;
40 class ObjCInterfaceDecl;
41 class ObjCIvarDecl;
42 class PointerType;
43 class QualType;
44 class RecordDecl;
45 class TagDecl;
46 class TargetInfo;
47 class Type;
48 typedef CanQual<Type> CanQualType;
49 class GlobalDecl;
50
51 namespace CodeGen {
52 class ABIInfo;
53 class CGCXXABI;
54 class CGRecordLayout;
55 class CodeGenModule;
56 class RequiredArgs;
57
58 enum class StructorType {
59 Complete, // constructor or destructor
60 Base, // constructor or destructor
61 Deleting // destructor only
62 };
63
64 inline CXXCtorType toCXXCtorType(StructorType T) {
65 switch (T) {
66 case StructorType::Complete:
67 return Ctor_Complete;
68 case StructorType::Base:
69 return Ctor_Base;
70 case StructorType::Deleting:
71 llvm_unreachable("cannot have a deleting ctor");
72 }
73 llvm_unreachable("not a StructorType");
74 }
75
76 inline StructorType getFromCtorType(CXXCtorType T) {
77 switch (T) {
78 case Ctor_Complete:
79 return StructorType::Complete;
80 case Ctor_Base:
81 return StructorType::Base;
82 case Ctor_Comdat:
83 llvm_unreachable("not expecting a COMDAT");
84 case Ctor_CopyingClosure:
85 case Ctor_DefaultClosure:
86 llvm_unreachable("not expecting a closure");
87 }
88 llvm_unreachable("not a CXXCtorType");
89 }
90
91 inline CXXDtorType toCXXDtorType(StructorType T) {
92 switch (T) {
93 case StructorType::Complete:
94 return Dtor_Complete;
95 case StructorType::Base:
96 return Dtor_Base;
97 case StructorType::Deleting:
98 return Dtor_Deleting;
99 }
100 llvm_unreachable("not a StructorType");
101 }
102
103 inline StructorType getFromDtorType(CXXDtorType T) {
104 switch (T) {
105 case Dtor_Deleting:
106 return StructorType::Deleting;
107 case Dtor_Complete:
108 return StructorType::Complete;
109 case Dtor_Base:
110 return StructorType::Base;
111 case Dtor_Comdat:
112 llvm_unreachable("not expecting a COMDAT");
113 }
114 llvm_unreachable("not a CXXDtorType");
115 }
116
117 /// This class organizes the cross-module state that is used while lowering
118 /// AST types to LLVM types.
119 class CodeGenTypes {
120 CodeGenModule &CGM;
121 // Some of this stuff should probably be left on the CGM.
122 ASTContext &Context;
123 llvm::Module &TheModule;
124 const TargetInfo &Target;
125 CGCXXABI &TheCXXABI;
126
127 // This should not be moved earlier, since its initialization depends on some
128 // of the previous reference members being already initialized
129 const ABIInfo &TheABIInfo;
130
131 /// The opaque type map for Objective-C interfaces. All direct
132 /// manipulation is done by the runtime interfaces, which are
133 /// responsible for coercing to the appropriate type; these opaque
134 /// types are never refined.
135 llvm::DenseMap<const ObjCInterfaceType*, llvm::Type *> InterfaceTypes;
136
137 /// Maps clang struct type with corresponding record layout info.
138 llvm::DenseMap<const Type*, CGRecordLayout *> CGRecordLayouts;
139
140 /// Contains the LLVM IR type for any converted RecordDecl.
141 llvm::DenseMap<const Type*, llvm::StructType *> RecordDeclTypes;
142
143 /// Hold memoized CGFunctionInfo results.
144 llvm::FoldingSet<CGFunctionInfo> FunctionInfos;
145
146 /// This set keeps track of records that we're currently converting
147 /// to an IR type. For example, when converting:
148 /// struct A { struct B { int x; } } when processing 'x', the 'A' and 'B'
149 /// types will be in this set.
150 llvm::SmallPtrSet<const Type*, 4> RecordsBeingLaidOut;
151
152 llvm::SmallPtrSet<const CGFunctionInfo*, 4> FunctionsBeingProcessed;
153
154 /// True if we didn't layout a function due to a being inside
155 /// a recursive struct conversion, set this to true.
156 bool SkippedLayout;
157
158 SmallVector<const RecordDecl *, 8> DeferredRecords;
159
160 /// This map keeps cache of llvm::Types and maps clang::Type to
161 /// corresponding llvm::Type.
162 llvm::DenseMap<const Type *, llvm::Type *> TypeCache;
163
164 llvm::SmallSet<const Type *, 8> RecordsWithOpaqueMemberPointers;
165
166 public:
167 CodeGenTypes(CodeGenModule &cgm);
168 ~CodeGenTypes();
169
170 const llvm::DataLayout &getDataLayout() const {
171 return TheModule.getDataLayout();
172 }
173 ASTContext &getContext() const { return Context; }
174 const ABIInfo &getABIInfo() const { return TheABIInfo; }
175 const TargetInfo &getTarget() const { return Target; }
176 CGCXXABI &getCXXABI() const { return TheCXXABI; }
177 llvm::LLVMContext &getLLVMContext() { return TheModule.getContext(); }
178 const CodeGenOptions &getCodeGenOpts() const;
179
180 /// Convert clang calling convention to LLVM callilng convention.
181 unsigned ClangCallConvToLLVMCallConv(CallingConv CC);
182
183 /// ConvertType - Convert type T into a llvm::Type.
184 llvm::Type *ConvertType(QualType T);
185
186 /// Converts the GlobalDecl into an llvm::Type. This should be used
187 /// when we know the target of the function we want to convert. This is
188 /// because some functions (explicitly, those with pass_object_size
189 /// parameters) may not have the same signature as their type portrays, and
190 /// can only be called directly.
191 llvm::Type *ConvertFunctionType(QualType FT,
192 const FunctionDecl *FD = nullptr);
193
194 /// ConvertTypeForMem - Convert type T into a llvm::Type. This differs from
195 /// ConvertType in that it is used to convert to the memory representation for
196 /// a type. For example, the scalar representation for _Bool is i1, but the
197 /// memory representation is usually i8 or i32, depending on the target.
198 llvm::Type *ConvertTypeForMem(QualType T);
199
200 /// GetFunctionType - Get the LLVM function type for \arg Info.
201 llvm::FunctionType *GetFunctionType(const CGFunctionInfo &Info);
202
203 llvm::FunctionType *GetFunctionType(GlobalDecl GD);
204
205 /// isFuncTypeConvertible - Utility to check whether a function type can
206 /// be converted to an LLVM type (i.e. doesn't depend on an incomplete tag
207 /// type).
208 bool isFuncTypeConvertible(const FunctionType *FT);
209 bool isFuncParamTypeConvertible(QualType Ty);
210
211 /// Determine if a C++ inheriting constructor should have parameters matching
212 /// those of its inherited constructor.
213 bool inheritingCtorHasParams(const InheritedConstructor &Inherited,
214 CXXCtorType Type);
215
216 /// GetFunctionTypeForVTable - Get the LLVM function type for use in a vtable,
217 /// given a CXXMethodDecl. If the method to has an incomplete return type,
218 /// and/or incomplete argument types, this will return the opaque type.
219 llvm::Type *GetFunctionTypeForVTable(GlobalDecl GD);
220
221 const CGRecordLayout &getCGRecordLayout(const RecordDecl*);
222
223 /// UpdateCompletedType - When we find the full definition for a TagDecl,
224 /// replace the 'opaque' type we previously made for it if applicable.
225 void UpdateCompletedType(const TagDecl *TD);
226
227 /// Remove stale types from the type cache when an inheritance model
228 /// gets assigned to a class.
229 void RefreshTypeCacheForClass(const CXXRecordDecl *RD);
230
231 // The arrangement methods are split into three families:
232 // - those meant to drive the signature and prologue/epilogue
233 // of a function declaration or definition,
234 // - those meant for the computation of the LLVM type for an abstract
235 // appearance of a function, and
236 // - those meant for performing the IR-generation of a call.
237 // They differ mainly in how they deal with optional (i.e. variadic)
238 // arguments, as well as unprototyped functions.
239 //
240 // Key points:
241 // - The CGFunctionInfo for emitting a specific call site must include
242 // entries for the optional arguments.
243 // - The function type used at the call site must reflect the formal
244 // signature of the declaration being called, or else the call will
245 // go awry.
246 // - For the most part, unprototyped functions are called by casting to
247 // a formal signature inferred from the specific argument types used
248 // at the call-site. However, some targets (e.g. x86-64) screw with
249 // this for compatibility reasons.
250
251 const CGFunctionInfo &arrangeGlobalDeclaration(GlobalDecl GD);
252
253 /// Given a function info for a declaration, return the function info
254 /// for a call with the given arguments.
255 ///
256 /// Often this will be able to simply return the declaration info.
257 const CGFunctionInfo &arrangeCall(const CGFunctionInfo &declFI,
258 const CallArgList &args);
259
260 /// Free functions are functions that are compatible with an ordinary
261 /// C function pointer type.
262 const CGFunctionInfo &arrangeFunctionDeclaration(const FunctionDecl *FD);
263 const CGFunctionInfo &arrangeFreeFunctionCall(const CallArgList &Args,
264 const FunctionType *Ty,
265 bool ChainCall);
266 const CGFunctionInfo &arrangeFreeFunctionType(CanQual<FunctionProtoType> Ty,
267 const FunctionDecl *FD);
268 const CGFunctionInfo &arrangeFreeFunctionType(CanQual<FunctionNoProtoType> Ty);
269
270 /// A nullary function is a freestanding function of type 'void ()'.
271 /// This method works for both calls and declarations.
272 const CGFunctionInfo &arrangeNullaryFunction();
273
274 /// A builtin function is a freestanding function using the default
275 /// C conventions.
276 const CGFunctionInfo &
277 arrangeBuiltinFunctionDeclaration(QualType resultType,
278 const FunctionArgList &args);
279 const CGFunctionInfo &
280 arrangeBuiltinFunctionDeclaration(CanQualType resultType,
281 ArrayRef<CanQualType> argTypes);
282 const CGFunctionInfo &arrangeBuiltinFunctionCall(QualType resultType,
283 const CallArgList &args);
284
285 /// Objective-C methods are C functions with some implicit parameters.
286 const CGFunctionInfo &arrangeObjCMethodDeclaration(const ObjCMethodDecl *MD);
287 const CGFunctionInfo &arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD,
288 QualType receiverType);
289 const CGFunctionInfo &arrangeUnprototypedObjCMessageSend(
290 QualType returnType,
291 const CallArgList &args);
292
293 /// Block invocation functions are C functions with an implicit parameter.
294 const CGFunctionInfo &arrangeBlockFunctionDeclaration(
295 const FunctionProtoType *type,
296 const FunctionArgList &args);
297 const CGFunctionInfo &arrangeBlockFunctionCall(const CallArgList &args,
298 const FunctionType *type);
299
300 /// C++ methods have some special rules and also have implicit parameters.
301 const CGFunctionInfo &arrangeCXXMethodDeclaration(const CXXMethodDecl *MD);
302 const CGFunctionInfo &arrangeCXXStructorDeclaration(const CXXMethodDecl *MD,
303 StructorType Type);
304 const CGFunctionInfo &arrangeCXXConstructorCall(const CallArgList &Args,
305 const CXXConstructorDecl *D,
306 CXXCtorType CtorKind,
307 unsigned ExtraPrefixArgs,
308 unsigned ExtraSuffixArgs,
309 bool PassProtoArgs = true);
310
311 const CGFunctionInfo &arrangeCXXMethodCall(const CallArgList &args,
312 const FunctionProtoType *type,
313 RequiredArgs required,
314 unsigned numPrefixArgs);
315 const CGFunctionInfo &
316 arrangeUnprototypedMustTailThunk(const CXXMethodDecl *MD);
317 const CGFunctionInfo &arrangeMSCtorClosure(const CXXConstructorDecl *CD,
318 CXXCtorType CT);
319 const CGFunctionInfo &arrangeCXXMethodType(const CXXRecordDecl *RD,
320 const FunctionProtoType *FTP,
321 const CXXMethodDecl *MD);
322
323 /// "Arrange" the LLVM information for a call or type with the given
324 /// signature. This is largely an internal method; other clients
325 /// should use one of the above routines, which ultimately defer to
326 /// this.
327 ///
328 /// \param argTypes - must all actually be canonical as params
329 const CGFunctionInfo &arrangeLLVMFunctionInfo(CanQualType returnType,
330 bool instanceMethod,
331 bool chainCall,
332 ArrayRef<CanQualType> argTypes,
333 FunctionType::ExtInfo info,
334 ArrayRef<FunctionProtoType::ExtParameterInfo> paramInfos,
335 RequiredArgs args);
336
337 /// Compute a new LLVM record layout object for the given record.
338 CGRecordLayout *ComputeRecordLayout(const RecordDecl *D,
339 llvm::StructType *Ty);
340
341 /// addRecordTypeName - Compute a name from the given record decl with an
342 /// optional suffix and name the given LLVM type using it.
343 void addRecordTypeName(const RecordDecl *RD, llvm::StructType *Ty,
344 StringRef suffix);
345
346
347 public: // These are internal details of CGT that shouldn't be used externally.
348 /// ConvertRecordDeclType - Lay out a tagged decl type like struct or union.
349 llvm::StructType *ConvertRecordDeclType(const RecordDecl *TD);
350
351 /// getExpandedTypes - Expand the type \arg Ty into the LLVM
352 /// argument types it would be passed as. See ABIArgInfo::Expand.
353 void getExpandedTypes(QualType Ty,
354 SmallVectorImpl<llvm::Type *>::iterator &TI);
355
356 /// IsZeroInitializable - Return whether a type can be
357 /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer.
358 bool isZeroInitializable(QualType T);
359
360 /// Check if the pointer type can be zero-initialized (in the C++ sense)
361 /// with an LLVM zeroinitializer.
362 bool isPointerZeroInitializable(QualType T);
363
364 /// IsZeroInitializable - Return whether a record type can be
365 /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer.
366 bool isZeroInitializable(const RecordDecl *RD);
367
368 bool isRecordLayoutComplete(const Type *Ty) const;
369 bool noRecordsBeingLaidOut() const {
370 return RecordsBeingLaidOut.empty();
371 }
372 bool isRecordBeingLaidOut(const Type *Ty) const {
373 return RecordsBeingLaidOut.count(Ty);
374 }
375
376 };
377
378 } // end namespace CodeGen
379 } // end namespace clang
380
381 #endif
clang::CodeGen::CodeGenTypes::noRecordsBeingLaidOut
bool noRecordsBeingLaidOut() const
Definition: CodeGenTypes.h:369
clang::CodeGen::CodeGenTypes::getCXXABI
CGCXXABI & getCXXABI() const
Definition: CodeGenTypes.h:176
clang::FunctionDecl
Represents a function declaration or definition.
Definition: Decl.h:1738
clang::Ctor_Complete
Complete object ctor.
Definition: ABI.h:26
clang::QualType
A (possibly-)qualified type.
Definition: Type.h:638
CGCall.h
clang::CodeGen::CGRecordLayout
CGRecordLayout - This class handles struct and union layout info while lowering AST types to LLVM typ...
Definition: CGRecordLayout.h:109
clang::Ctor_Comdat
The COMDAT used for ctors.
Definition: ABI.h:28
llvm
DominatorTree GraphTraits specialization so the DominatorTree can be iterable by generic graph iterat...
Definition: Dominators.h:30
clang::CodeGen::CodeGenTypes::getABIInfo
const ABIInfo & getABIInfo() const
Definition: CodeGenTypes.h:174
clang::FunctionType
FunctionType - C99 6.7.5.3 - Function Declarators.
Definition: Type.h:3355
Base
clang::CodeGen::CodeGenTypes::isRecordBeingLaidOut
bool isRecordBeingLaidOut(const Type *Ty) const
Definition: CodeGenTypes.h:372
clang::CodeGen::CodeGenTypes::getDataLayout
const llvm::DataLayout & getDataLayout() const
Definition: CodeGenTypes.h:170
clang::Type
The base class of the type hierarchy.
Definition: Type.h:1407
clang::CodeGen::StructorType::Deleting
clang::CXXConstructorDecl
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2484
clang::Ctor_DefaultClosure
Default closure variant of a ctor.
Definition: ABI.h:30
clang::ObjCMethodDecl
ObjCMethodDecl - Represents an instance or class method declaration.
Definition: DeclObjC.h:139
clang::CodeGen::arrangeCXXMethodType
const CGFunctionInfo & arrangeCXXMethodType(CodeGenModule &CGM, const CXXRecordDecl *RD, const FunctionProtoType *FTP, const CXXMethodDecl *MD)
Definition: CodeGenABITypes.cpp:50
clang::MultiVersionKind::Target
clang::RecordDecl
Represents a struct/union/class.
Definition: Decl.h:3593
clang::InheritedConstructor
Description of a constructor that was inherited from a base class.
Definition: DeclCXX.h:2458
clang::ASTContext
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:155
clang::CodeGen::StructorType
StructorType
Definition: CodeGenTypes.h:58
clang::CodeGen::getFromDtorType
StructorType getFromDtorType(CXXDtorType T)
Definition: CodeGenTypes.h:103
llvm::SmallVectorImpl
Definition: LLVM.h:37
clang::CodeGen::arrangeFreeFunctionType
const CGFunctionInfo & arrangeFreeFunctionType(CodeGenModule &CGM, CanQual< FunctionProtoType > Ty, const FunctionDecl *FD)
Definition: CodeGenABITypes.cpp:37
clang::Ctor_Base
Base object ctor.
Definition: ABI.h:27
clang::Dtor_Deleting
Deleting dtor.
Definition: ABI.h:35
ABI.h
Enums/classes describing ABI related information about constructors, destructors and thunks...
CGFunctionInfo.h
llvm::ArrayRef
Definition: LLVM.h:32
clang::CodeGen::arrangeObjCMessageSendSignature
const CGFunctionInfo & arrangeObjCMessageSendSignature(CodeGenModule &CGM, const ObjCMethodDecl *MD, QualType receiverType)
Definition: CodeGenABITypes.cpp:30
clang::FunctionProtoType
Represents a prototype with parameter type info, e.g.
Definition: Type.h:3687
clang::TargetInfo
Exposes information about the current target.
Definition: TargetInfo.h:54
clang::CXXDtorType
CXXDtorType
C++ destructor types.
Definition: ABI.h:34
clang::CodeGen::StructorType::Complete
clang::CodeGen::RequiredArgs
A class for recording the number of arguments that a function signature requires. ...
Definition: CGFunctionInfo.h:426
clang::Dtor_Base
Base object dtor.
Definition: ABI.h:37
clang::Dtor_Comdat
The COMDAT used for dtors.
Definition: ABI.h:38
clang::CallingConv
CallingConv
CallingConv - Specifies the calling convention that a function uses.
Definition: Specifiers.h:236
clang::GlobalDecl
GlobalDecl - represents a global declaration.
Definition: GlobalDecl.h:35
clang::TagDecl
Represents the declaration of a struct/union/class/enum.
Definition: Decl.h:3064
clang::CXXMethodDecl
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2041
clang::CodeGen::arrangeFreeFunctionCall
const CGFunctionInfo & arrangeFreeFunctionCall(CodeGenModule &CGM, CanQualType returnType, ArrayRef< CanQualType > argTypes, FunctionType::ExtInfo info, RequiredArgs args)
Definition: CodeGenABITypes.cpp:58
clang::CanQual< FunctionProtoType >
clang::CanQualType
CanQual< Type > CanQualType
Represents a canonical, potentially-qualified type.
Definition: CanonicalType.h:213
llvm::SmallVector
Definition: LLVM.h:36
clang::CodeGen::CodeGenTypes::getLLVMContext
llvm::LLVMContext & getLLVMContext()
Definition: CodeGenTypes.h:177
clang::Dtor_Complete
Complete object dtor.
Definition: ABI.h:36
clang::CXXCtorType
CXXCtorType
C++ constructor types.
Definition: ABI.h:25
clang::CodeGen::FunctionArgList
FunctionArgList - Type for representing both the decl and type of parameters to a function...
Definition: CGCall.h:356
clang::CodeGen::CodeGenTypes::getTarget
const TargetInfo & getTarget() const
Definition: CodeGenTypes.h:175
clang::CodeGen::CGFunctionInfo
CGFunctionInfo - Class to encapsulate the information about a function definition.
Definition: CGFunctionInfo.h:493
clang::CodeGen::CodeGenModule
This class organizes the cross-function state that is used while generating LLVM code.
Definition: CodeGenModule.h:274
Type
Optional< types::ID > Type
Definition: InterpolatingCompilationDatabase.cpp:128
clang
Dataflow Directional Tag Classes.
Definition: CFGReachabilityAnalysis.h:22
clang::CodeGen::toCXXDtorType
CXXDtorType toCXXDtorType(StructorType T)
Definition: CodeGenTypes.h:91
arrangeLLVMFunctionInfo
static const CGFunctionInfo & arrangeLLVMFunctionInfo(CodeGenTypes &CGT, bool instanceMethod, SmallVectorImpl< CanQualType > &prefix, CanQual< FunctionProtoType > FTP, const FunctionDecl *FD)
Arrange the LLVM function layout for a value of the given function type, on top of any implicit param...
Definition: CGCall.cpp:170
type
clang::CodeGen::getFromCtorType
StructorType getFromCtorType(CXXCtorType T)
Definition: CodeGenTypes.h:76
clang::CodeGen::CGCXXABI
Implements C++ ABI-specific code generation functions.
Definition: CGCXXABI.h:44
clang::CodeGen::CodeGenTypes
This class organizes the cross-module state that is used while lowering AST types to LLVM types...
Definition: CodeGenTypes.h:119
clang::CodeGenOptions
CodeGenOptions - Track various options which control how the code is optimized and passed to the back...
Definition: CodeGenOptions.h:46
clang::CodeGen::CodeGenTypes::getContext
ASTContext & getContext() const
Definition: CodeGenTypes.h:173
clang::CXXRecordDecl
Represents a C++ struct/union/class.
Definition: DeclCXX.h:300
clang::Ctor_CopyingClosure
Copying closure variant of a ctor.
Definition: ABI.h:29
clang::CodeGen::ABIInfo
ABIInfo - Target specific hooks for defining how a type should be passed or returned from functions...
Definition: ABIInfo.h:51
clang::CodeGen::toCXXCtorType
CXXCtorType toCXXCtorType(StructorType T)
Definition: CodeGenTypes.h:64
clang::CodeGen::CallArgList
CallArgList - Type for representing both the value and type of arguments in a call.
Definition: CGCall.h:260
clang::FunctionType::ExtInfo
A class which abstracts out some details necessary for making a call.
Definition: Type.h:3466