clang 17.0.0git
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 CGCXXABI &TheCXXABI;
61
62 // This should not be moved earlier, since its initialization depends on some
63 // of the previous reference members being already initialized
64 const ABIInfo &TheABIInfo;
65
66 /// The opaque type map for Objective-C interfaces. All direct
67 /// manipulation is done by the runtime interfaces, which are
68 /// responsible for coercing to the appropriate type; these opaque
69 /// types are never refined.
70 llvm::DenseMap<const ObjCInterfaceType*, llvm::Type *> InterfaceTypes;
71
72 /// Maps clang struct type with corresponding record layout info.
73 llvm::DenseMap<const Type*, std::unique_ptr<CGRecordLayout>> CGRecordLayouts;
74
75 /// Contains the LLVM IR type for any converted RecordDecl.
76 llvm::DenseMap<const Type*, llvm::StructType *> RecordDeclTypes;
77
78 /// Hold memoized CGFunctionInfo results.
79 llvm::FoldingSet<CGFunctionInfo> FunctionInfos{FunctionInfosLog2InitSize};
80
81 /// This set keeps track of records that we're currently converting
82 /// to an IR type. For example, when converting:
83 /// struct A { struct B { int x; } } when processing 'x', the 'A' and 'B'
84 /// types will be in this set.
85 llvm::SmallPtrSet<const Type*, 4> RecordsBeingLaidOut;
86
87 llvm::SmallPtrSet<const CGFunctionInfo*, 4> FunctionsBeingProcessed;
88
89 /// True if we didn't layout a function due to a being inside
90 /// a recursive struct conversion, set this to true.
91 bool SkippedLayout;
92
94
95 /// This map keeps cache of llvm::Types and maps clang::Type to
96 /// corresponding llvm::Type.
97 llvm::DenseMap<const Type *, llvm::Type *> TypeCache;
98
99 llvm::DenseMap<const Type *, llvm::Type *> RecordsWithOpaqueMemberPointers;
100
101 static constexpr unsigned FunctionInfosLog2InitSize = 9;
102 /// Helper for ConvertType.
103 llvm::Type *ConvertFunctionTypeInternal(QualType FT);
104
105public:
108
109 const llvm::DataLayout &getDataLayout() const {
110 return TheModule.getDataLayout();
111 }
112 CodeGenModule &getCGM() const { return CGM; }
113 ASTContext &getContext() const { return Context; }
114 const ABIInfo &getABIInfo() const { return TheABIInfo; }
115 const TargetInfo &getTarget() const { return Target; }
116 CGCXXABI &getCXXABI() const { return TheCXXABI; }
117 llvm::LLVMContext &getLLVMContext() { return TheModule.getContext(); }
118 const CodeGenOptions &getCodeGenOpts() const;
119
120 /// Convert clang calling convention to LLVM callilng convention.
122
123 /// Derives the 'this' type for codegen purposes, i.e. ignoring method CVR
124 /// qualification.
126
127 /// ConvertType - Convert type T into a llvm::Type.
128 llvm::Type *ConvertType(QualType T);
129
130 /// ConvertTypeForMem - Convert type T into a llvm::Type. This differs from
131 /// ConvertType in that it is used to convert to the memory representation for
132 /// a type. For example, the scalar representation for _Bool is i1, but the
133 /// memory representation is usually i8 or i32, depending on the target.
134 llvm::Type *ConvertTypeForMem(QualType T, bool ForBitField = false);
135
136 /// GetFunctionType - Get the LLVM function type for \arg Info.
137 llvm::FunctionType *GetFunctionType(const CGFunctionInfo &Info);
138
139 llvm::FunctionType *GetFunctionType(GlobalDecl GD);
140
141 /// isFuncTypeConvertible - Utility to check whether a function type can
142 /// be converted to an LLVM type (i.e. doesn't depend on an incomplete tag
143 /// type).
144 bool isFuncTypeConvertible(const FunctionType *FT);
146
147 /// Determine if a C++ inheriting constructor should have parameters matching
148 /// those of its inherited constructor.
149 bool inheritingCtorHasParams(const InheritedConstructor &Inherited,
151
152 /// GetFunctionTypeForVTable - Get the LLVM function type for use in a vtable,
153 /// given a CXXMethodDecl. If the method to has an incomplete return type,
154 /// and/or incomplete argument types, this will return the opaque type.
155 llvm::Type *GetFunctionTypeForVTable(GlobalDecl GD);
156
158
159 /// UpdateCompletedType - When we find the full definition for a TagDecl,
160 /// replace the 'opaque' type we previously made for it if applicable.
161 void UpdateCompletedType(const TagDecl *TD);
162
163 /// Remove stale types from the type cache when an inheritance model
164 /// gets assigned to a class.
166
167 // The arrangement methods are split into three families:
168 // - those meant to drive the signature and prologue/epilogue
169 // of a function declaration or definition,
170 // - those meant for the computation of the LLVM type for an abstract
171 // appearance of a function, and
172 // - those meant for performing the IR-generation of a call.
173 // They differ mainly in how they deal with optional (i.e. variadic)
174 // arguments, as well as unprototyped functions.
175 //
176 // Key points:
177 // - The CGFunctionInfo for emitting a specific call site must include
178 // entries for the optional arguments.
179 // - The function type used at the call site must reflect the formal
180 // signature of the declaration being called, or else the call will
181 // go awry.
182 // - For the most part, unprototyped functions are called by casting to
183 // a formal signature inferred from the specific argument types used
184 // at the call-site. However, some targets (e.g. x86-64) screw with
185 // this for compatibility reasons.
186
188
189 /// Given a function info for a declaration, return the function info
190 /// for a call with the given arguments.
191 ///
192 /// Often this will be able to simply return the declaration info.
193 const CGFunctionInfo &arrangeCall(const CGFunctionInfo &declFI,
194 const CallArgList &args);
195
196 /// Free functions are functions that are compatible with an ordinary
197 /// C function pointer type.
200 const FunctionType *Ty,
201 bool ChainCall);
204
205 /// A nullary function is a freestanding function of type 'void ()'.
206 /// This method works for both calls and declarations.
208
209 /// A builtin function is a freestanding function using the default
210 /// C conventions.
211 const CGFunctionInfo &
213 const FunctionArgList &args);
214 const CGFunctionInfo &
216 ArrayRef<CanQualType> argTypes);
218 const CallArgList &args);
219
220 /// Objective-C methods are C functions with some implicit parameters.
223 QualType receiverType);
225 QualType returnType,
226 const CallArgList &args);
227
228 /// Block invocation functions are C functions with an implicit parameter.
230 const FunctionProtoType *type,
231 const FunctionArgList &args);
233 const FunctionType *type);
234
235 /// C++ methods have some special rules and also have implicit parameters.
239 const CXXConstructorDecl *D,
240 CXXCtorType CtorKind,
241 unsigned ExtraPrefixArgs,
242 unsigned ExtraSuffixArgs,
243 bool PassProtoArgs = true);
244
246 const FunctionProtoType *type,
247 RequiredArgs required,
248 unsigned numPrefixArgs);
249 const CGFunctionInfo &
252 CXXCtorType CT);
254 const FunctionProtoType *FTP,
255 const CXXMethodDecl *MD);
256
257 /// "Arrange" the LLVM information for a call or type with the given
258 /// signature. This is largely an internal method; other clients
259 /// should use one of the above routines, which ultimately defer to
260 /// this.
261 ///
262 /// \param argTypes - must all actually be canonical as params
264 bool instanceMethod,
265 bool chainCall,
266 ArrayRef<CanQualType> argTypes,
269 RequiredArgs args);
270
271 /// Compute a new LLVM record layout object for the given record.
272 std::unique_ptr<CGRecordLayout> ComputeRecordLayout(const RecordDecl *D,
273 llvm::StructType *Ty);
274
275 /// addRecordTypeName - Compute a name from the given record decl with an
276 /// optional suffix and name the given LLVM type using it.
277 void addRecordTypeName(const RecordDecl *RD, llvm::StructType *Ty,
278 StringRef suffix);
279
280
281public: // These are internal details of CGT that shouldn't be used externally.
282 /// ConvertRecordDeclType - Lay out a tagged decl type like struct or union.
283 llvm::StructType *ConvertRecordDeclType(const RecordDecl *TD);
284
285 /// getExpandedTypes - Expand the type \arg Ty into the LLVM
286 /// argument types it would be passed as. See ABIArgInfo::Expand.
289
290 /// IsZeroInitializable - Return whether a type can be
291 /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer.
293
294 /// Check if the pointer type can be zero-initialized (in the C++ sense)
295 /// with an LLVM zeroinitializer.
297
298 /// IsZeroInitializable - Return whether a record type can be
299 /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer.
300 bool isZeroInitializable(const RecordDecl *RD);
301
302 bool isRecordLayoutComplete(const Type *Ty) const;
304 return RecordsBeingLaidOut.empty();
305 }
306 bool isRecordBeingLaidOut(const Type *Ty) const {
307 return RecordsBeingLaidOut.count(Ty);
308 }
309 unsigned getTargetAddressSpace(QualType T) const;
310};
311
312} // end namespace CodeGen
313} // end namespace clang
314
315#endif
Enums/classes describing ABI related information about constructors, destructors and thunks.
MatchType Type
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:182
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2474
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2018
Represents a C++ struct/union/class.
Definition: DeclCXX.h:254
CodeGenOptions - Track various options which control how the code is optimized and passed to the back...
ABIInfo - Target specific hooks for defining how a type should be passed or returned from functions.
Definition: ABIInfo.h:45
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:259
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:264
const CGFunctionInfo & arrangeLLVMFunctionInfo(CanQualType returnType, bool instanceMethod, bool chainCall, 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:755
bool noRecordsBeingLaidOut() const
Definition: CodeGenTypes.h:303
llvm::Type * ConvertType(QualType T)
ConvertType - Convert type T into a llvm::Type.
const CGFunctionInfo & arrangeCXXMethodDeclaration(const CXXMethodDecl *MD)
C++ methods have some special rules and also have implicit parameters.
Definition: CGCall.cpp:292
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:113
const ABIInfo & getABIInfo() const
Definition: CodeGenTypes.h:114
const CGFunctionInfo & arrangeFreeFunctionType(CanQual< FunctionProtoType > Ty)
Arrange the argument and result information for a value of the given freestanding function type.
Definition: CGCall.cpp:200
CanQualType DeriveThisType(const CXXRecordDecl *RD, const CXXMethodDecl *MD)
Derives the 'this' type for codegen purposes, i.e.
Definition: CGCall.cpp:80
llvm::FunctionType * GetFunctionType(const CGFunctionInfo &Info)
GetFunctionType - Get the LLVM function type for.
Definition: CGCall.cpp:1618
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:309
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:639
const CGFunctionInfo & arrangeBuiltinFunctionDeclaration(QualType resultType, const FunctionArgList &args)
A builtin function is a freestanding function using the default C conventions.
Definition: CGCall.cpp:671
const CGFunctionInfo & arrangeUnprototypedObjCMessageSend(QualType returnType, const CallArgList &args)
Definition: CGCall.cpp:520
const TargetInfo & getTarget() const
Definition: CodeGenTypes.h:115
std::unique_ptr< CGRecordLayout > ComputeRecordLayout(const RecordDecl *D, llvm::StructType *Ty)
Compute a new LLVM record layout object for the given record.
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:999
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.
const CGFunctionInfo & arrangeObjCMethodDeclaration(const ObjCMethodDecl *MD)
Objective-C methods are C functions with some implicit parameters.
Definition: CGCall.cpp:474
CodeGenModule & getCGM() const
Definition: CodeGenTypes.h:112
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:117
const CGFunctionInfo & arrangeGlobalDeclaration(GlobalDecl GD)
Definition: CGCall.cpp:531
const CGFunctionInfo & arrangeUnprototypedMustTailThunk(const CXXMethodDecl *MD)
Arrange a thunk that takes 'this' as the first parameter followed by varargs.
Definition: CGCall.cpp:548
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:693
const llvm::DataLayout & getDataLayout() const
Definition: CodeGenTypes.h:109
CGCXXABI & getCXXABI() const
Definition: CodeGenTypes.h:116
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:629
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:658
const CGFunctionInfo & arrangeFunctionDeclaration(const FunctionDecl *FD)
Free functions are functions that are compatible with an ordinary C function pointer type.
Definition: CGCall.cpp:449
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:646
unsigned ClangCallConvToLLVMCallConv(CallingConv CC)
Convert clang calling convention to LLVM callilng convention.
Definition: CGCall.cpp:48
llvm::Type * ConvertTypeForMem(QualType T, bool ForBitField=false)
ConvertTypeForMem - Convert type T into a llvm::Type.
llvm::Type * GetFunctionTypeForVTable(GlobalDecl GD)
GetFunctionTypeForVTable - Get the LLVM function type for use in a vtable, given a CXXMethodDecl.
Definition: CGCall.cpp:1752
bool isRecordBeingLaidOut(const Type *Ty) const
Definition: CodeGenTypes.h:306
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:405
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:487
const CGFunctionInfo & arrangeCXXStructorDeclaration(GlobalDecl GD)
Definition: CGCall.cpp:319
const CGFunctionInfo & arrangeMSCtorClosure(const CXXConstructorDecl *CD, CXXCtorType CT)
Definition: CGCall.cpp:558
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:720
const CGFunctionInfo & arrangeNullaryFunction()
A nullary function is a freestanding function of type 'void ()'.
Definition: CGCall.cpp:713
FunctionArgList - Type for representing both the decl and type of parameters to a function.
Definition: CGCall.h:353
A class for recording the number of arguments that a function signature requires.
Represents a function declaration or definition.
Definition: Decl.h:1917
Represents a prototype with parameter type info, e.g.
Definition: Type.h:4041
A class which abstracts out some details necessary for making a call.
Definition: Type.h:3805
FunctionType - C99 6.7.5.3 - Function Declarators.
Definition: Type.h:3694
GlobalDecl - represents a global declaration.
Definition: GlobalDecl.h:56
Description of a constructor that was inherited from a base class.
Definition: DeclCXX.h:2445
ObjCMethodDecl - Represents an instance or class method declaration.
Definition: DeclObjC.h:138
A (possibly-)qualified type.
Definition: Type.h:736
Represents a struct/union/class.
Definition: Decl.h:3998
Represents the declaration of a struct/union/class/enum.
Definition: Decl.h:3440
Exposes information about the current target.
Definition: TargetInfo.h:206
The base class of the type hierarchy.
Definition: Type.h:1566
const internal::VariadicAllOfMatcher< Type > type
Matches Types in the clang AST.
CXXCtorType
C++ constructor types.
Definition: ABI.h:24
CanQual< Type > CanQualType
Represents a canonical, potentially-qualified type.
CallingConv
CallingConv - Specifies the calling convention that a function uses.
Definition: Specifiers.h:266
YAML serialization mapping.
Definition: Dominators.h:30