clang 20.0.0git
CodeGenTypes.h
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1//===--- CodeGenTypes.h - Type translation for LLVM CodeGen -----*- 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// This is the code that handles AST -> LLVM type lowering.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_CLANG_LIB_CODEGEN_CODEGENTYPES_H
14#define LLVM_CLANG_LIB_CODEGEN_CODEGENTYPES_H
15
16#include "CGCall.h"
17#include "clang/Basic/ABI.h"
19#include "llvm/ADT/DenseMap.h"
20#include "llvm/IR/Module.h"
21
22namespace llvm {
23class FunctionType;
24class DataLayout;
25class Type;
26class LLVMContext;
27class StructType;
28}
29
30namespace clang {
31class ASTContext;
32template <typename> class CanQual;
33class CXXConstructorDecl;
34class CXXMethodDecl;
35class CodeGenOptions;
36class FunctionProtoType;
37class QualType;
38class RecordDecl;
39class TagDecl;
40class TargetInfo;
41class Type;
42typedef CanQual<Type> CanQualType;
43class GlobalDecl;
44
45namespace CodeGen {
46class ABIInfo;
47class CGCXXABI;
48class CGRecordLayout;
49class CodeGenModule;
50class RequiredArgs;
51
52/// This class organizes the cross-module state that is used while lowering
53/// AST types to LLVM types.
55 CodeGenModule &CGM;
56 // Some of this stuff should probably be left on the CGM.
57 ASTContext &Context;
58 llvm::Module &TheModule;
59 const TargetInfo &Target;
60
61 /// The opaque type map for Objective-C interfaces. All direct
62 /// manipulation is done by the runtime interfaces, which are
63 /// responsible for coercing to the appropriate type; these opaque
64 /// types are never refined.
65 llvm::DenseMap<const ObjCInterfaceType*, llvm::Type *> InterfaceTypes;
66
67 /// Maps clang struct type with corresponding record layout info.
68 llvm::DenseMap<const Type*, std::unique_ptr<CGRecordLayout>> CGRecordLayouts;
69
70 /// Contains the LLVM IR type for any converted RecordDecl.
71 llvm::DenseMap<const Type*, llvm::StructType *> RecordDeclTypes;
72
73 /// Hold memoized CGFunctionInfo results.
74 llvm::FoldingSet<CGFunctionInfo> FunctionInfos{FunctionInfosLog2InitSize};
75
76 llvm::SmallPtrSet<const CGFunctionInfo*, 4> FunctionsBeingProcessed;
77
78 /// True if we didn't layout a function due to a being inside
79 /// a recursive struct conversion, set this to true.
80 bool SkippedLayout;
81
82 /// True if any instance of long double types are used.
83 bool LongDoubleReferenced;
84
85 /// This map keeps cache of llvm::Types and maps clang::Type to
86 /// corresponding llvm::Type.
87 llvm::DenseMap<const Type *, llvm::Type *> TypeCache;
88
89 llvm::DenseMap<const Type *, llvm::Type *> RecordsWithOpaqueMemberPointers;
90
91 static constexpr unsigned FunctionInfosLog2InitSize = 9;
92 /// Helper for ConvertType.
93 llvm::Type *ConvertFunctionTypeInternal(QualType FT);
94
95public:
98
99 const llvm::DataLayout &getDataLayout() const {
100 return TheModule.getDataLayout();
101 }
102 CodeGenModule &getCGM() const { return CGM; }
103 ASTContext &getContext() const { return Context; }
104 const TargetInfo &getTarget() const { return Target; }
105 CGCXXABI &getCXXABI() const;
106 llvm::LLVMContext &getLLVMContext() { return TheModule.getContext(); }
107 const CodeGenOptions &getCodeGenOpts() const;
108
109 /// Convert clang calling convention to LLVM callilng convention.
111
112 /// Derives the 'this' type for codegen purposes, i.e. ignoring method CVR
113 /// qualification.
115
116 /// ConvertType - Convert type T into a llvm::Type.
117 llvm::Type *ConvertType(QualType T);
118
119 /// ConvertTypeForMem - Convert type T into a llvm::Type. This differs from
120 /// ConvertType in that it is used to convert to the memory representation for
121 /// a type. For example, the scalar representation for _Bool is i1, but the
122 /// memory representation is usually i8 or i32, depending on the target.
123 llvm::Type *ConvertTypeForMem(QualType T);
124
125 /// Check whether the given type needs to be laid out in memory
126 /// using an opaque byte-array type because its load/store type
127 /// does not have the correct alloc size in the LLVM data layout.
128 /// If this is false, the load/store type (convertTypeForLoadStore)
129 /// and memory representation type (ConvertTypeForMem) will
130 /// be the same type.
132 llvm::Type *LLVMTy = nullptr);
133
134 /// Given that T is a scalar type, return the IR type that should
135 /// be used for load and store operations. For example, this might
136 /// be i8 for _Bool or i96 for _BitInt(65). The store size of the
137 /// load/store type (as reported by LLVM's data layout) is always
138 /// the same as the alloc size of the memory representation type
139 /// returned by ConvertTypeForMem.
140 ///
141 /// As an optimization, if you already know the scalar value type
142 /// for T (as would be returned by ConvertType), you can pass
143 /// it as the second argument so that it does not need to be
144 /// recomputed in common cases where the value type and
145 /// load/store type are the same.
146 llvm::Type *convertTypeForLoadStore(QualType T, llvm::Type *LLVMTy = nullptr);
147
148 /// GetFunctionType - Get the LLVM function type for \arg Info.
149 llvm::FunctionType *GetFunctionType(const CGFunctionInfo &Info);
150
151 llvm::FunctionType *GetFunctionType(GlobalDecl GD);
152
153 /// isFuncTypeConvertible - Utility to check whether a function type can
154 /// be converted to an LLVM type (i.e. doesn't depend on an incomplete tag
155 /// type).
156 bool isFuncTypeConvertible(const FunctionType *FT);
158
159 /// Determine if a C++ inheriting constructor should have parameters matching
160 /// those of its inherited constructor.
161 bool inheritingCtorHasParams(const InheritedConstructor &Inherited,
163
164 /// GetFunctionTypeForVTable - Get the LLVM function type for use in a vtable,
165 /// given a CXXMethodDecl. If the method to has an incomplete return type,
166 /// and/or incomplete argument types, this will return the opaque type.
167 llvm::Type *GetFunctionTypeForVTable(GlobalDecl GD);
168
170
171 /// UpdateCompletedType - When we find the full definition for a TagDecl,
172 /// replace the 'opaque' type we previously made for it if applicable.
173 void UpdateCompletedType(const TagDecl *TD);
174
175 /// Remove stale types from the type cache when an inheritance model
176 /// gets assigned to a class.
178
179 // The arrangement methods are split into three families:
180 // - those meant to drive the signature and prologue/epilogue
181 // of a function declaration or definition,
182 // - those meant for the computation of the LLVM type for an abstract
183 // appearance of a function, and
184 // - those meant for performing the IR-generation of a call.
185 // They differ mainly in how they deal with optional (i.e. variadic)
186 // arguments, as well as unprototyped functions.
187 //
188 // Key points:
189 // - The CGFunctionInfo for emitting a specific call site must include
190 // entries for the optional arguments.
191 // - The function type used at the call site must reflect the formal
192 // signature of the declaration being called, or else the call will
193 // go awry.
194 // - For the most part, unprototyped functions are called by casting to
195 // a formal signature inferred from the specific argument types used
196 // at the call-site. However, some targets (e.g. x86-64) screw with
197 // this for compatibility reasons.
198
200
201 /// Given a function info for a declaration, return the function info
202 /// for a call with the given arguments.
203 ///
204 /// Often this will be able to simply return the declaration info.
205 const CGFunctionInfo &arrangeCall(const CGFunctionInfo &declFI,
206 const CallArgList &args);
207
208 /// Free functions are functions that are compatible with an ordinary
209 /// C function pointer type.
212 const FunctionType *Ty,
213 bool ChainCall);
216
217 /// A nullary function is a freestanding function of type 'void ()'.
218 /// This method works for both calls and declarations.
220
221 /// A builtin function is a freestanding function using the default
222 /// C conventions.
223 const CGFunctionInfo &
225 const FunctionArgList &args);
226 const CGFunctionInfo &
228 ArrayRef<CanQualType> argTypes);
230 const CallArgList &args);
231
232 /// Objective-C methods are C functions with some implicit parameters.
235 QualType receiverType);
237 QualType returnType,
238 const CallArgList &args);
239
240 /// Block invocation functions are C functions with an implicit parameter.
242 const FunctionProtoType *type,
243 const FunctionArgList &args);
245 const FunctionType *type);
246
247 /// C++ methods have some special rules and also have implicit parameters.
251 const CXXConstructorDecl *D,
252 CXXCtorType CtorKind,
253 unsigned ExtraPrefixArgs,
254 unsigned ExtraSuffixArgs,
255 bool PassProtoArgs = true);
256
258 const FunctionProtoType *type,
259 RequiredArgs required,
260 unsigned numPrefixArgs);
261 const CGFunctionInfo &
264 CXXCtorType CT);
266 const FunctionProtoType *FTP,
267 const CXXMethodDecl *MD);
268
269 /// "Arrange" the LLVM information for a call or type with the given
270 /// signature. This is largely an internal method; other clients
271 /// should use one of the above routines, which ultimately defer to
272 /// this.
273 ///
274 /// \param argTypes - must all actually be canonical as params
276 CanQualType returnType, FnInfoOpts opts, ArrayRef<CanQualType> argTypes,
279 RequiredArgs args);
280
281 /// Compute a new LLVM record layout object for the given record.
282 std::unique_ptr<CGRecordLayout> ComputeRecordLayout(const RecordDecl *D,
283 llvm::StructType *Ty);
284
285 /// addRecordTypeName - Compute a name from the given record decl with an
286 /// optional suffix and name the given LLVM type using it.
287 void addRecordTypeName(const RecordDecl *RD, llvm::StructType *Ty,
288 StringRef suffix);
289
290
291public: // These are internal details of CGT that shouldn't be used externally.
292 /// ConvertRecordDeclType - Lay out a tagged decl type like struct or union.
293 llvm::StructType *ConvertRecordDeclType(const RecordDecl *TD);
294
295 /// getExpandedTypes - Expand the type \arg Ty into the LLVM
296 /// argument types it would be passed as. See ABIArgInfo::Expand.
299
300 /// IsZeroInitializable - Return whether a type can be
301 /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer.
303
304 /// Check if the pointer type can be zero-initialized (in the C++ sense)
305 /// with an LLVM zeroinitializer.
307
308 /// IsZeroInitializable - Return whether a record type can be
309 /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer.
310 bool isZeroInitializable(const RecordDecl *RD);
311
312 bool isLongDoubleReferenced() const { return LongDoubleReferenced; }
313 bool isRecordLayoutComplete(const Type *Ty) const;
314 unsigned getTargetAddressSpace(QualType T) const;
315};
316
317} // end namespace CodeGen
318} // end namespace clang
319
320#endif
Enums/classes describing ABI related information about constructors, destructors and thunks.
MatchType Type
const Decl * D
llvm::MachO::Target Target
Definition: MachO.h:51
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:187
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2539
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2064
Represents a C++ struct/union/class.
Definition: DeclCXX.h:258
CodeGenOptions - Track various options which control how the code is optimized and passed to the back...
Implements C++ ABI-specific code generation functions.
Definition: CGCXXABI.h:43
CGFunctionInfo - Class to encapsulate the information about a function definition.
CGRecordLayout - This class handles struct and union layout info while lowering AST types to LLVM typ...
CallArgList - Type for representing both the value and type of arguments in a call.
Definition: CGCall.h:274
This class organizes the cross-function state that is used while generating LLVM code.
This class organizes the cross-module state that is used while lowering AST types to LLVM types.
Definition: CodeGenTypes.h:54
const CGFunctionInfo & arrangeCXXMethodType(const CXXRecordDecl *RD, const FunctionProtoType *FTP, const CXXMethodDecl *MD)
Arrange the argument and result information for a call to an unknown C++ non-static member function o...
Definition: CGCall.cpp:279
llvm::Type * ConvertType(QualType T)
ConvertType - Convert type T into a llvm::Type.
CGCXXABI & getCXXABI() const
const CGFunctionInfo & arrangeCXXMethodDeclaration(const CXXMethodDecl *MD)
C++ methods have some special rules and also have implicit parameters.
Definition: CGCall.cpp:307
bool isPointerZeroInitializable(QualType T)
Check if the pointer type can be zero-initialized (in the C++ sense) with an LLVM zeroinitializer.
const CodeGenOptions & getCodeGenOpts() const
ASTContext & getContext() const
Definition: CodeGenTypes.h:103
const CGFunctionInfo & arrangeLLVMFunctionInfo(CanQualType returnType, FnInfoOpts opts, ArrayRef< CanQualType > argTypes, FunctionType::ExtInfo info, ArrayRef< FunctionProtoType::ExtParameterInfo > paramInfos, RequiredArgs args)
"Arrange" the LLVM information for a call or type with the given signature.
Definition: CGCall.cpp:765
const CGFunctionInfo & arrangeFreeFunctionType(CanQual< FunctionProtoType > Ty)
Arrange the argument and result information for a value of the given freestanding function type.
Definition: CGCall.cpp:206
CanQualType DeriveThisType(const CXXRecordDecl *RD, const CXXMethodDecl *MD)
Derives the 'this' type for codegen purposes, i.e.
Definition: CGCall.cpp:87
llvm::FunctionType * GetFunctionType(const CGFunctionInfo &Info)
GetFunctionType - Get the LLVM function type for.
Definition: CGCall.cpp:1606
bool inheritingCtorHasParams(const InheritedConstructor &Inherited, CXXCtorType Type)
Determine if a C++ inheriting constructor should have parameters matching those of its inherited cons...
Definition: CGCall.cpp:325
bool isFuncTypeConvertible(const FunctionType *FT)
isFuncTypeConvertible - Utility to check whether a function type can be converted to an LLVM type (i....
const CGFunctionInfo & arrangeBlockFunctionCall(const CallArgList &args, const FunctionType *type)
A block function is essentially a free function with an extra implicit argument.
Definition: CGCall.cpp:648
const CGFunctionInfo & arrangeBuiltinFunctionDeclaration(QualType resultType, const FunctionArgList &args)
A builtin function is a freestanding function using the default C conventions.
Definition: CGCall.cpp:679
const CGFunctionInfo & arrangeUnprototypedObjCMessageSend(QualType returnType, const CallArgList &args)
Definition: CGCall.cpp:532
const TargetInfo & getTarget() const
Definition: CodeGenTypes.h:104
std::unique_ptr< CGRecordLayout > ComputeRecordLayout(const RecordDecl *D, llvm::StructType *Ty)
Compute a new LLVM record layout object for the given record.
llvm::Type * convertTypeForLoadStore(QualType T, llvm::Type *LLVMTy=nullptr)
Given that T is a scalar type, return the IR type that should be used for load and store operations.
const CGRecordLayout & getCGRecordLayout(const RecordDecl *)
getCGRecordLayout - Return record layout info for the given record decl.
unsigned getTargetAddressSpace(QualType T) const
void getExpandedTypes(QualType Ty, SmallVectorImpl< llvm::Type * >::iterator &TI)
getExpandedTypes - Expand the type
Definition: CGCall.cpp:1013
llvm::StructType * ConvertRecordDeclType(const RecordDecl *TD)
ConvertRecordDeclType - Lay out a tagged decl type like struct or union.
void RefreshTypeCacheForClass(const CXXRecordDecl *RD)
Remove stale types from the type cache when an inheritance model gets assigned to a class.
bool isRecordLayoutComplete(const Type *Ty) const
isRecordLayoutComplete - Return true if the specified type is already completely laid out.
llvm::Type * ConvertTypeForMem(QualType T)
ConvertTypeForMem - Convert type T into a llvm::Type.
const CGFunctionInfo & arrangeObjCMethodDeclaration(const ObjCMethodDecl *MD)
Objective-C methods are C functions with some implicit parameters.
Definition: CGCall.cpp:486
CodeGenModule & getCGM() const
Definition: CodeGenTypes.h:102
void UpdateCompletedType(const TagDecl *TD)
UpdateCompletedType - When we find the full definition for a TagDecl, replace the 'opaque' type we pr...
llvm::LLVMContext & getLLVMContext()
Definition: CodeGenTypes.h:106
bool typeRequiresSplitIntoByteArray(QualType ASTTy, llvm::Type *LLVMTy=nullptr)
Check whether the given type needs to be laid out in memory using an opaque byte-array type because i...
const CGFunctionInfo & arrangeGlobalDeclaration(GlobalDecl GD)
Definition: CGCall.cpp:542
bool isLongDoubleReferenced() const
Definition: CodeGenTypes.h:312
const CGFunctionInfo & arrangeUnprototypedMustTailThunk(const CXXMethodDecl *MD)
Arrange a thunk that takes 'this' as the first parameter followed by varargs.
Definition: CGCall.cpp:559
const CGFunctionInfo & arrangeCXXMethodCall(const CallArgList &args, const FunctionProtoType *type, RequiredArgs required, unsigned numPrefixArgs)
Arrange a call to a C++ method, passing the given arguments.
Definition: CGCall.cpp:701
const llvm::DataLayout & getDataLayout() const
Definition: CodeGenTypes.h:99
const CGFunctionInfo & arrangeFreeFunctionCall(const CallArgList &Args, const FunctionType *Ty, bool ChainCall)
Figure out the rules for calling a function with the given formal type using the given arguments.
Definition: CGCall.cpp:638
bool isFuncParamTypeConvertible(QualType Ty)
isFuncParamTypeConvertible - Return true if the specified type in a function parameter or result posi...
const CGFunctionInfo & arrangeBuiltinFunctionCall(QualType resultType, const CallArgList &args)
Definition: CGCall.cpp:667
const CGFunctionInfo & arrangeFunctionDeclaration(const FunctionDecl *FD)
Free functions are functions that are compatible with an ordinary C function pointer type.
Definition: CGCall.cpp:462
bool isZeroInitializable(QualType T)
IsZeroInitializable - Return whether a type can be zero-initialized (in the C++ sense) with an LLVM z...
const CGFunctionInfo & arrangeBlockFunctionDeclaration(const FunctionProtoType *type, const FunctionArgList &args)
Block invocation functions are C functions with an implicit parameter.
Definition: CGCall.cpp:655
unsigned ClangCallConvToLLVMCallConv(CallingConv CC)
Convert clang calling convention to LLVM callilng convention.
Definition: CGCall.cpp:50
llvm::Type * GetFunctionTypeForVTable(GlobalDecl GD)
GetFunctionTypeForVTable - Get the LLVM function type for use in a vtable, given a CXXMethodDecl.
Definition: CGCall.cpp:1733
void addRecordTypeName(const RecordDecl *RD, llvm::StructType *Ty, StringRef suffix)
addRecordTypeName - Compute a name from the given record decl with an optional suffix and name the gi...
const CGFunctionInfo & arrangeCXXConstructorCall(const CallArgList &Args, const CXXConstructorDecl *D, CXXCtorType CtorKind, unsigned ExtraPrefixArgs, unsigned ExtraSuffixArgs, bool PassProtoArgs=true)
Arrange a call to a C++ method, passing the given arguments.
Definition: CGCall.cpp:419
const CGFunctionInfo & arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD, QualType receiverType)
Arrange the argument and result information for the function type through which to perform a send to ...
Definition: CGCall.cpp:499
const CGFunctionInfo & arrangeCXXStructorDeclaration(GlobalDecl GD)
Definition: CGCall.cpp:335
const CGFunctionInfo & arrangeMSCtorClosure(const CXXConstructorDecl *CD, CXXCtorType CT)
Definition: CGCall.cpp:568
const CGFunctionInfo & arrangeCall(const CGFunctionInfo &declFI, const CallArgList &args)
Given a function info for a declaration, return the function info for a call with the given arguments...
Definition: CGCall.cpp:728
const CGFunctionInfo & arrangeNullaryFunction()
A nullary function is a freestanding function of type 'void ()'.
Definition: CGCall.cpp:721
FunctionArgList - Type for representing both the decl and type of parameters to a function.
Definition: CGCall.h:368
A class for recording the number of arguments that a function signature requires.
Represents a function declaration or definition.
Definition: Decl.h:1932
Represents a prototype with parameter type info, e.g.
Definition: Type.h:5007
A class which abstracts out some details necessary for making a call.
Definition: Type.h:4424
FunctionType - C99 6.7.5.3 - Function Declarators.
Definition: Type.h:4313
GlobalDecl - represents a global declaration.
Definition: GlobalDecl.h:56
Description of a constructor that was inherited from a base class.
Definition: DeclCXX.h:2510
ObjCMethodDecl - Represents an instance or class method declaration.
Definition: DeclObjC.h:140
A (possibly-)qualified type.
Definition: Type.h:941
Represents a struct/union/class.
Definition: Decl.h:4145
Represents the declaration of a struct/union/class/enum.
Definition: Decl.h:3561
Exposes information about the current target.
Definition: TargetInfo.h:218
The base class of the type hierarchy.
Definition: Type.h:1829
const internal::VariadicAllOfMatcher< Type > type
Matches Types in the clang AST.
The JSON file list parser is used to communicate input to InstallAPI.
CXXCtorType
C++ constructor types.
Definition: ABI.h:24
CanQual< Type > CanQualType
Represents a canonical, potentially-qualified type.
const FunctionProtoType * T
CallingConv
CallingConv - Specifies the calling convention that a function uses.
Definition: Specifiers.h:278
Diagnostic wrappers for TextAPI types for error reporting.
Definition: Dominators.h:30