1 //===--- Specifiers.h - Declaration and Type Specifiers ---------*- 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 /// Defines various enumerations that describe declaration and 11 /// type specifiers. 12 /// 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_CLANG_BASIC_SPECIFIERS_H 16 #define LLVM_CLANG_BASIC_SPECIFIERS_H 17 18 #include "llvm/ADT/StringRef.h" 19 #include "llvm/Support/DataTypes.h" 20 #include "llvm/Support/ErrorHandling.h" 21 22 namespace clang { 23 24 /// Define the meaning of possible values of the kind in ExplicitSpecifier. 25 enum class ExplicitSpecKind : unsigned { 26 ResolvedFalse, 27 ResolvedTrue, 28 Unresolved, 29 }; 30 31 /// Define the kind of constexpr specifier. 32 enum class ConstexprSpecKind { Unspecified, Constexpr, Consteval, Constinit }; 33 34 /// Specifies the width of a type, e.g., short, long, or long long. 35 enum class TypeSpecifierWidth { Unspecified, Short, Long, LongLong }; 36 37 /// Specifies the signedness of a type, e.g., signed or unsigned. 38 enum class TypeSpecifierSign { Unspecified, Signed, Unsigned }; 39 40 enum class TypeSpecifiersPipe { Unspecified, Pipe }; 41 42 /// Specifies the kind of type. 43 enum TypeSpecifierType { 44 TST_unspecified, 45 TST_void, 46 TST_char, 47 TST_wchar, // C++ wchar_t 48 TST_char8, // C++20 char8_t (proposed) 49 TST_char16, // C++11 char16_t 50 TST_char32, // C++11 char32_t 51 TST_int, 52 TST_int128, 53 TST_extint, // Extended Int types. 54 TST_half, // OpenCL half, ARM NEON __fp16 55 TST_Float16, // C11 extension ISO/IEC TS 18661-3 56 TST_Accum, // ISO/IEC JTC1 SC22 WG14 N1169 Extension 57 TST_Fract, 58 TST_BFloat16, 59 TST_float, 60 TST_double, 61 TST_float128, 62 TST_bool, // _Bool 63 TST_decimal32, // _Decimal32 64 TST_decimal64, // _Decimal64 65 TST_decimal128, // _Decimal128 66 TST_enum, 67 TST_union, 68 TST_struct, 69 TST_class, // C++ class type 70 TST_interface, // C++ (Microsoft-specific) __interface type 71 TST_typename, // Typedef, C++ class-name or enum name, etc. 72 TST_typeofType, 73 TST_typeofExpr, 74 TST_decltype, // C++11 decltype 75 TST_underlyingType, // __underlying_type for C++11 76 TST_auto, // C++11 auto 77 TST_decltype_auto, // C++1y decltype(auto) 78 TST_auto_type, // __auto_type extension 79 TST_unknown_anytype, // __unknown_anytype extension 80 TST_atomic, // C11 _Atomic 81 #define GENERIC_IMAGE_TYPE(ImgType, Id) TST_##ImgType##_t, // OpenCL image types 82 #include "clang/Basic/OpenCLImageTypes.def" 83 TST_error // erroneous type 84 }; 85 86 /// Structure that packs information about the type specifiers that 87 /// were written in a particular type specifier sequence. 88 struct WrittenBuiltinSpecs { 89 static_assert(TST_error < 1 << 6, "Type bitfield not wide enough for TST"); 90 /*DeclSpec::TST*/ unsigned Type : 6; 91 /*DeclSpec::TSS*/ unsigned Sign : 2; 92 /*TypeSpecifierWidth*/ unsigned Width : 2; 93 unsigned ModeAttr : 1; 94 }; 95 96 /// A C++ access specifier (public, private, protected), plus the 97 /// special value "none" which means different things in different contexts. 98 enum AccessSpecifier { 99 AS_public, 100 AS_protected, 101 AS_private, 102 AS_none 103 }; 104 105 /// The categorization of expression values, currently following the 106 /// C++11 scheme. 107 enum ExprValueKind { 108 /// An r-value expression (a pr-value in the C++11 taxonomy) 109 /// produces a temporary value. 110 VK_RValue, 111 112 /// An l-value expression is a reference to an object with 113 /// independent storage. 114 VK_LValue, 115 116 /// An x-value expression is a reference to an object with 117 /// independent storage but which can be "moved", i.e. 118 /// efficiently cannibalized for its resources. 119 VK_XValue 120 }; 121 122 /// A further classification of the kind of object referenced by an 123 /// l-value or x-value. 124 enum ExprObjectKind { 125 /// An ordinary object is located at an address in memory. 126 OK_Ordinary, 127 128 /// A bitfield object is a bitfield on a C or C++ record. 129 OK_BitField, 130 131 /// A vector component is an element or range of elements on a vector. 132 OK_VectorComponent, 133 134 /// An Objective-C property is a logical field of an Objective-C 135 /// object which is read and written via Objective-C method calls. 136 OK_ObjCProperty, 137 138 /// An Objective-C array/dictionary subscripting which reads an 139 /// object or writes at the subscripted array/dictionary element via 140 /// Objective-C method calls. 141 OK_ObjCSubscript, 142 143 /// A matrix component is a single element of a matrix. 144 OK_MatrixComponent 145 }; 146 147 /// The reason why a DeclRefExpr does not constitute an odr-use. 148 enum NonOdrUseReason { 149 /// This is an odr-use. 150 NOUR_None = 0, 151 /// This name appears in an unevaluated operand. 152 NOUR_Unevaluated, 153 /// This name appears as a potential result of an lvalue-to-rvalue 154 /// conversion that is a constant expression. 155 NOUR_Constant, 156 /// This name appears as a potential result of a discarded value 157 /// expression. 158 NOUR_Discarded, 159 }; 160 161 /// Describes the kind of template specialization that a 162 /// particular template specialization declaration represents. 163 enum TemplateSpecializationKind { 164 /// This template specialization was formed from a template-id but 165 /// has not yet been declared, defined, or instantiated. 166 TSK_Undeclared = 0, 167 /// This template specialization was implicitly instantiated from a 168 /// template. (C++ [temp.inst]). 169 TSK_ImplicitInstantiation, 170 /// This template specialization was declared or defined by an 171 /// explicit specialization (C++ [temp.expl.spec]) or partial 172 /// specialization (C++ [temp.class.spec]). 173 TSK_ExplicitSpecialization, 174 /// This template specialization was instantiated from a template 175 /// due to an explicit instantiation declaration request 176 /// (C++11 [temp.explicit]). 177 TSK_ExplicitInstantiationDeclaration, 178 /// This template specialization was instantiated from a template 179 /// due to an explicit instantiation definition request 180 /// (C++ [temp.explicit]). 181 TSK_ExplicitInstantiationDefinition 182 }; 183 184 /// Determine whether this template specialization kind refers 185 /// to an instantiation of an entity (as opposed to a non-template or 186 /// an explicit specialization). isTemplateInstantiation(TemplateSpecializationKind Kind)187 inline bool isTemplateInstantiation(TemplateSpecializationKind Kind) { 188 return Kind != TSK_Undeclared && Kind != TSK_ExplicitSpecialization; 189 } 190 191 /// True if this template specialization kind is an explicit 192 /// specialization, explicit instantiation declaration, or explicit 193 /// instantiation definition. isTemplateExplicitInstantiationOrSpecialization(TemplateSpecializationKind Kind)194 inline bool isTemplateExplicitInstantiationOrSpecialization( 195 TemplateSpecializationKind Kind) { 196 switch (Kind) { 197 case TSK_ExplicitSpecialization: 198 case TSK_ExplicitInstantiationDeclaration: 199 case TSK_ExplicitInstantiationDefinition: 200 return true; 201 202 case TSK_Undeclared: 203 case TSK_ImplicitInstantiation: 204 return false; 205 } 206 llvm_unreachable("bad template specialization kind"); 207 } 208 209 /// Thread storage-class-specifier. 210 enum ThreadStorageClassSpecifier { 211 TSCS_unspecified, 212 /// GNU __thread. 213 TSCS___thread, 214 /// C++11 thread_local. Implies 'static' at block scope, but not at 215 /// class scope. 216 TSCS_thread_local, 217 /// C11 _Thread_local. Must be combined with either 'static' or 'extern' 218 /// if used at block scope. 219 TSCS__Thread_local 220 }; 221 222 /// Storage classes. 223 enum StorageClass { 224 // These are legal on both functions and variables. 225 SC_None, 226 SC_Extern, 227 SC_Static, 228 SC_PrivateExtern, 229 230 // These are only legal on variables. 231 SC_Auto, 232 SC_Register 233 }; 234 235 /// Checks whether the given storage class is legal for functions. isLegalForFunction(StorageClass SC)236 inline bool isLegalForFunction(StorageClass SC) { 237 return SC <= SC_PrivateExtern; 238 } 239 240 /// Checks whether the given storage class is legal for variables. isLegalForVariable(StorageClass SC)241 inline bool isLegalForVariable(StorageClass SC) { 242 return true; 243 } 244 245 /// In-class initialization styles for non-static data members. 246 enum InClassInitStyle { 247 ICIS_NoInit, ///< No in-class initializer. 248 ICIS_CopyInit, ///< Copy initialization. 249 ICIS_ListInit ///< Direct list-initialization. 250 }; 251 252 /// CallingConv - Specifies the calling convention that a function uses. 253 enum CallingConv { 254 CC_C, // __attribute__((cdecl)) 255 CC_X86StdCall, // __attribute__((stdcall)) 256 CC_X86FastCall, // __attribute__((fastcall)) 257 CC_X86ThisCall, // __attribute__((thiscall)) 258 CC_X86VectorCall, // __attribute__((vectorcall)) 259 CC_X86Pascal, // __attribute__((pascal)) 260 CC_Win64, // __attribute__((ms_abi)) 261 CC_X86_64SysV, // __attribute__((sysv_abi)) 262 CC_X86RegCall, // __attribute__((regcall)) 263 CC_AAPCS, // __attribute__((pcs("aapcs"))) 264 CC_AAPCS_VFP, // __attribute__((pcs("aapcs-vfp"))) 265 CC_IntelOclBicc, // __attribute__((intel_ocl_bicc)) 266 CC_SpirFunction, // default for OpenCL functions on SPIR target 267 CC_OpenCLKernel, // inferred for OpenCL kernels 268 CC_Swift, // __attribute__((swiftcall)) 269 CC_PreserveMost, // __attribute__((preserve_most)) 270 CC_PreserveAll, // __attribute__((preserve_all)) 271 CC_AArch64VectorCall, // __attribute__((aarch64_vector_pcs)) 272 }; 273 274 /// Checks whether the given calling convention supports variadic 275 /// calls. Unprototyped calls also use the variadic call rules. supportsVariadicCall(CallingConv CC)276 inline bool supportsVariadicCall(CallingConv CC) { 277 switch (CC) { 278 case CC_X86StdCall: 279 case CC_X86FastCall: 280 case CC_X86ThisCall: 281 case CC_X86RegCall: 282 case CC_X86Pascal: 283 case CC_X86VectorCall: 284 case CC_SpirFunction: 285 case CC_OpenCLKernel: 286 case CC_Swift: 287 return false; 288 default: 289 return true; 290 } 291 } 292 293 /// The storage duration for an object (per C++ [basic.stc]). 294 enum StorageDuration { 295 SD_FullExpression, ///< Full-expression storage duration (for temporaries). 296 SD_Automatic, ///< Automatic storage duration (most local variables). 297 SD_Thread, ///< Thread storage duration. 298 SD_Static, ///< Static storage duration. 299 SD_Dynamic ///< Dynamic storage duration. 300 }; 301 302 /// Describes the nullability of a particular type. 303 enum class NullabilityKind : uint8_t { 304 /// Values of this type can never be null. 305 NonNull = 0, 306 /// Values of this type can be null. 307 Nullable, 308 /// Whether values of this type can be null is (explicitly) 309 /// unspecified. This captures a (fairly rare) case where we 310 /// can't conclude anything about the nullability of the type even 311 /// though it has been considered. 312 Unspecified, 313 // Generally behaves like Nullable, except when used in a block parameter 314 // that was imported into a swift async method. There, swift will assume 315 // that the parameter can get null even if no error occured. _Nullable 316 // parameters are assumed to only get null on error. 317 NullableResult, 318 }; 319 320 /// Return true if \p L has a weaker nullability annotation than \p R. The 321 /// ordering is: Unspecified < Nullable < NonNull. hasWeakerNullability(NullabilityKind L,NullabilityKind R)322 inline bool hasWeakerNullability(NullabilityKind L, NullabilityKind R) { 323 return uint8_t(L) > uint8_t(R); 324 } 325 326 /// Retrieve the spelling of the given nullability kind. 327 llvm::StringRef getNullabilitySpelling(NullabilityKind kind, 328 bool isContextSensitive = false); 329 330 /// Kinds of parameter ABI. 331 enum class ParameterABI { 332 /// This parameter uses ordinary ABI rules for its type. 333 Ordinary, 334 335 /// This parameter (which must have pointer type) is a Swift 336 /// indirect result parameter. 337 SwiftIndirectResult, 338 339 /// This parameter (which must have pointer-to-pointer type) uses 340 /// the special Swift error-result ABI treatment. There can be at 341 /// most one parameter on a given function that uses this treatment. 342 SwiftErrorResult, 343 344 /// This parameter (which must have pointer type) uses the special 345 /// Swift context-pointer ABI treatment. There can be at 346 /// most one parameter on a given function that uses this treatment. 347 SwiftContext 348 }; 349 350 /// Assigned inheritance model for a class in the MS C++ ABI. Must match order 351 /// of spellings in MSInheritanceAttr. 352 enum class MSInheritanceModel { 353 Single = 0, 354 Multiple = 1, 355 Virtual = 2, 356 Unspecified = 3, 357 }; 358 359 llvm::StringRef getParameterABISpelling(ParameterABI kind); 360 getAccessSpelling(AccessSpecifier AS)361 inline llvm::StringRef getAccessSpelling(AccessSpecifier AS) { 362 switch (AS) { 363 case AccessSpecifier::AS_public: 364 return "public"; 365 case AccessSpecifier::AS_protected: 366 return "protected"; 367 case AccessSpecifier::AS_private: 368 return "private"; 369 case AccessSpecifier::AS_none: 370 return {}; 371 } 372 llvm_unreachable("Unknown AccessSpecifier"); 373 } 374 } // end namespace clang 375 376 #endif // LLVM_CLANG_BASIC_SPECIFIERS_H 377