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 llvm { 23 class raw_ostream; 24 } // namespace llvm 25 namespace clang { 26 27 /// Define the meaning of possible values of the kind in ExplicitSpecifier. 28 enum class ExplicitSpecKind : unsigned { 29 ResolvedFalse, 30 ResolvedTrue, 31 Unresolved, 32 }; 33 34 /// Define the kind of constexpr specifier. 35 enum class ConstexprSpecKind { Unspecified, Constexpr, Consteval, Constinit }; 36 37 /// In an if statement, this denotes whether the statement is 38 /// a constexpr or consteval if statement. 39 enum class IfStatementKind : unsigned { 40 Ordinary, 41 Constexpr, 42 ConstevalNonNegated, 43 ConstevalNegated 44 }; 45 46 /// Specifies the width of a type, e.g., short, long, or long long. 47 enum class TypeSpecifierWidth { Unspecified, Short, Long, LongLong }; 48 49 /// Specifies the signedness of a type, e.g., signed or unsigned. 50 enum class TypeSpecifierSign { Unspecified, Signed, Unsigned }; 51 52 enum class TypeSpecifiersPipe { Unspecified, Pipe }; 53 54 /// Specifies the kind of type. 55 enum TypeSpecifierType { 56 TST_unspecified, 57 TST_void, 58 TST_char, 59 TST_wchar, // C++ wchar_t 60 TST_char8, // C++20 char8_t (proposed) 61 TST_char16, // C++11 char16_t 62 TST_char32, // C++11 char32_t 63 TST_int, 64 TST_int128, 65 TST_bitint, // Bit-precise integer types. 66 TST_half, // OpenCL half, ARM NEON __fp16 67 TST_Float16, // C11 extension ISO/IEC TS 18661-3 68 TST_Accum, // ISO/IEC JTC1 SC22 WG14 N1169 Extension 69 TST_Fract, 70 TST_BFloat16, 71 TST_float, 72 TST_double, 73 TST_float128, 74 TST_ibm128, 75 TST_bool, // _Bool 76 TST_decimal32, // _Decimal32 77 TST_decimal64, // _Decimal64 78 TST_decimal128, // _Decimal128 79 TST_enum, 80 TST_union, 81 TST_struct, 82 TST_class, // C++ class type 83 TST_interface, // C++ (Microsoft-specific) __interface type 84 TST_typename, // Typedef, C++ class-name or enum name, etc. 85 TST_typeofType, // C2x (and GNU extension) typeof(type-name) 86 TST_typeofExpr, // C2x (and GNU extension) typeof(expression) 87 TST_typeof_unqualType, // C2x typeof_unqual(type-name) 88 TST_typeof_unqualExpr, // C2x typeof_unqual(expression) 89 TST_decltype, // C++11 decltype 90 #define TRANSFORM_TYPE_TRAIT_DEF(_, Trait) TST_##Trait, 91 #include "clang/Basic/TransformTypeTraits.def" 92 TST_auto, // C++11 auto 93 TST_decltype_auto, // C++1y decltype(auto) 94 TST_auto_type, // __auto_type extension 95 TST_unknown_anytype, // __unknown_anytype extension 96 TST_atomic, // C11 _Atomic 97 #define GENERIC_IMAGE_TYPE(ImgType, Id) TST_##ImgType##_t, // OpenCL image types 98 #include "clang/Basic/OpenCLImageTypes.def" 99 TST_error // erroneous type 100 }; 101 102 /// Structure that packs information about the type specifiers that 103 /// were written in a particular type specifier sequence. 104 struct WrittenBuiltinSpecs { 105 static_assert(TST_error < 1 << 7, "Type bitfield not wide enough for TST"); 106 /*DeclSpec::TST*/ unsigned Type : 7; 107 /*DeclSpec::TSS*/ unsigned Sign : 2; 108 /*TypeSpecifierWidth*/ unsigned Width : 2; 109 unsigned ModeAttr : 1; 110 }; 111 112 /// A C++ access specifier (public, private, protected), plus the 113 /// special value "none" which means different things in different contexts. 114 enum AccessSpecifier { 115 AS_public, 116 AS_protected, 117 AS_private, 118 AS_none 119 }; 120 121 /// The categorization of expression values, currently following the 122 /// C++11 scheme. 123 enum ExprValueKind { 124 /// A pr-value expression (in the C++11 taxonomy) 125 /// produces a temporary value. 126 VK_PRValue, 127 128 /// An l-value expression is a reference to an object with 129 /// independent storage. 130 VK_LValue, 131 132 /// An x-value expression is a reference to an object with 133 /// independent storage but which can be "moved", i.e. 134 /// efficiently cannibalized for its resources. 135 VK_XValue 136 }; 137 138 /// A further classification of the kind of object referenced by an 139 /// l-value or x-value. 140 enum ExprObjectKind { 141 /// An ordinary object is located at an address in memory. 142 OK_Ordinary, 143 144 /// A bitfield object is a bitfield on a C or C++ record. 145 OK_BitField, 146 147 /// A vector component is an element or range of elements on a vector. 148 OK_VectorComponent, 149 150 /// An Objective-C property is a logical field of an Objective-C 151 /// object which is read and written via Objective-C method calls. 152 OK_ObjCProperty, 153 154 /// An Objective-C array/dictionary subscripting which reads an 155 /// object or writes at the subscripted array/dictionary element via 156 /// Objective-C method calls. 157 OK_ObjCSubscript, 158 159 /// A matrix component is a single element of a matrix. 160 OK_MatrixComponent 161 }; 162 163 /// The reason why a DeclRefExpr does not constitute an odr-use. 164 enum NonOdrUseReason { 165 /// This is an odr-use. 166 NOUR_None = 0, 167 /// This name appears in an unevaluated operand. 168 NOUR_Unevaluated, 169 /// This name appears as a potential result of an lvalue-to-rvalue 170 /// conversion that is a constant expression. 171 NOUR_Constant, 172 /// This name appears as a potential result of a discarded value 173 /// expression. 174 NOUR_Discarded, 175 }; 176 177 /// Describes the kind of template specialization that a 178 /// particular template specialization declaration represents. 179 enum TemplateSpecializationKind { 180 /// This template specialization was formed from a template-id but 181 /// has not yet been declared, defined, or instantiated. 182 TSK_Undeclared = 0, 183 /// This template specialization was implicitly instantiated from a 184 /// template. (C++ [temp.inst]). 185 TSK_ImplicitInstantiation, 186 /// This template specialization was declared or defined by an 187 /// explicit specialization (C++ [temp.expl.spec]) or partial 188 /// specialization (C++ [temp.class.spec]). 189 TSK_ExplicitSpecialization, 190 /// This template specialization was instantiated from a template 191 /// due to an explicit instantiation declaration request 192 /// (C++11 [temp.explicit]). 193 TSK_ExplicitInstantiationDeclaration, 194 /// This template specialization was instantiated from a template 195 /// due to an explicit instantiation definition request 196 /// (C++ [temp.explicit]). 197 TSK_ExplicitInstantiationDefinition 198 }; 199 200 /// Determine whether this template specialization kind refers 201 /// to an instantiation of an entity (as opposed to a non-template or 202 /// an explicit specialization). 203 inline bool isTemplateInstantiation(TemplateSpecializationKind Kind) { 204 return Kind != TSK_Undeclared && Kind != TSK_ExplicitSpecialization; 205 } 206 207 /// True if this template specialization kind is an explicit 208 /// specialization, explicit instantiation declaration, or explicit 209 /// instantiation definition. 210 inline bool isTemplateExplicitInstantiationOrSpecialization( 211 TemplateSpecializationKind Kind) { 212 switch (Kind) { 213 case TSK_ExplicitSpecialization: 214 case TSK_ExplicitInstantiationDeclaration: 215 case TSK_ExplicitInstantiationDefinition: 216 return true; 217 218 case TSK_Undeclared: 219 case TSK_ImplicitInstantiation: 220 return false; 221 } 222 llvm_unreachable("bad template specialization kind"); 223 } 224 225 /// Thread storage-class-specifier. 226 enum ThreadStorageClassSpecifier { 227 TSCS_unspecified, 228 /// GNU __thread. 229 TSCS___thread, 230 /// C++11 thread_local. Implies 'static' at block scope, but not at 231 /// class scope. 232 TSCS_thread_local, 233 /// C11 _Thread_local. Must be combined with either 'static' or 'extern' 234 /// if used at block scope. 235 TSCS__Thread_local 236 }; 237 238 /// Storage classes. 239 enum StorageClass { 240 // These are legal on both functions and variables. 241 SC_None, 242 SC_Extern, 243 SC_Static, 244 SC_PrivateExtern, 245 246 // These are only legal on variables. 247 SC_Auto, 248 SC_Register 249 }; 250 251 /// Checks whether the given storage class is legal for functions. 252 inline bool isLegalForFunction(StorageClass SC) { 253 return SC <= SC_PrivateExtern; 254 } 255 256 /// Checks whether the given storage class is legal for variables. 257 inline bool isLegalForVariable(StorageClass SC) { 258 return true; 259 } 260 261 /// In-class initialization styles for non-static data members. 262 enum InClassInitStyle { 263 ICIS_NoInit, ///< No in-class initializer. 264 ICIS_CopyInit, ///< Copy initialization. 265 ICIS_ListInit ///< Direct list-initialization. 266 }; 267 268 /// CallingConv - Specifies the calling convention that a function uses. 269 enum CallingConv { 270 CC_C, // __attribute__((cdecl)) 271 CC_X86StdCall, // __attribute__((stdcall)) 272 CC_X86FastCall, // __attribute__((fastcall)) 273 CC_X86ThisCall, // __attribute__((thiscall)) 274 CC_X86VectorCall, // __attribute__((vectorcall)) 275 CC_X86Pascal, // __attribute__((pascal)) 276 CC_Win64, // __attribute__((ms_abi)) 277 CC_X86_64SysV, // __attribute__((sysv_abi)) 278 CC_X86RegCall, // __attribute__((regcall)) 279 CC_AAPCS, // __attribute__((pcs("aapcs"))) 280 CC_AAPCS_VFP, // __attribute__((pcs("aapcs-vfp"))) 281 CC_IntelOclBicc, // __attribute__((intel_ocl_bicc)) 282 CC_SpirFunction, // default for OpenCL functions on SPIR target 283 CC_OpenCLKernel, // inferred for OpenCL kernels 284 CC_Swift, // __attribute__((swiftcall)) 285 CC_SwiftAsync, // __attribute__((swiftasynccall)) 286 CC_PreserveMost, // __attribute__((preserve_most)) 287 CC_PreserveAll, // __attribute__((preserve_all)) 288 CC_AArch64VectorCall, // __attribute__((aarch64_vector_pcs)) 289 CC_AArch64SVEPCS, // __attribute__((aarch64_sve_pcs)) 290 CC_AMDGPUKernelCall, // __attribute__((amdgpu_kernel)) 291 }; 292 293 /// Checks whether the given calling convention supports variadic 294 /// calls. Unprototyped calls also use the variadic call rules. 295 inline bool supportsVariadicCall(CallingConv CC) { 296 switch (CC) { 297 case CC_X86StdCall: 298 case CC_X86FastCall: 299 case CC_X86ThisCall: 300 case CC_X86RegCall: 301 case CC_X86Pascal: 302 case CC_X86VectorCall: 303 case CC_SpirFunction: 304 case CC_OpenCLKernel: 305 case CC_Swift: 306 case CC_SwiftAsync: 307 return false; 308 default: 309 return true; 310 } 311 } 312 313 /// The storage duration for an object (per C++ [basic.stc]). 314 enum StorageDuration { 315 SD_FullExpression, ///< Full-expression storage duration (for temporaries). 316 SD_Automatic, ///< Automatic storage duration (most local variables). 317 SD_Thread, ///< Thread storage duration. 318 SD_Static, ///< Static storage duration. 319 SD_Dynamic ///< Dynamic storage duration. 320 }; 321 322 /// Describes the nullability of a particular type. 323 enum class NullabilityKind : uint8_t { 324 /// Values of this type can never be null. 325 NonNull = 0, 326 /// Values of this type can be null. 327 Nullable, 328 /// Whether values of this type can be null is (explicitly) 329 /// unspecified. This captures a (fairly rare) case where we 330 /// can't conclude anything about the nullability of the type even 331 /// though it has been considered. 332 Unspecified, 333 // Generally behaves like Nullable, except when used in a block parameter 334 // that was imported into a swift async method. There, swift will assume 335 // that the parameter can get null even if no error occurred. _Nullable 336 // parameters are assumed to only get null on error. 337 NullableResult, 338 }; 339 /// Prints human-readable debug representation. 340 llvm::raw_ostream &operator<<(llvm::raw_ostream&, NullabilityKind); 341 342 /// Return true if \p L has a weaker nullability annotation than \p R. The 343 /// ordering is: Unspecified < Nullable < NonNull. 344 inline bool hasWeakerNullability(NullabilityKind L, NullabilityKind R) { 345 return uint8_t(L) > uint8_t(R); 346 } 347 348 /// Retrieve the spelling of the given nullability kind. 349 llvm::StringRef getNullabilitySpelling(NullabilityKind kind, 350 bool isContextSensitive = false); 351 352 /// Kinds of parameter ABI. 353 enum class ParameterABI { 354 /// This parameter uses ordinary ABI rules for its type. 355 Ordinary, 356 357 /// This parameter (which must have pointer type) is a Swift 358 /// indirect result parameter. 359 SwiftIndirectResult, 360 361 /// This parameter (which must have pointer-to-pointer type) uses 362 /// the special Swift error-result ABI treatment. There can be at 363 /// most one parameter on a given function that uses this treatment. 364 SwiftErrorResult, 365 366 /// This parameter (which must have pointer type) uses the special 367 /// Swift context-pointer ABI treatment. There can be at 368 /// most one parameter on a given function that uses this treatment. 369 SwiftContext, 370 371 /// This parameter (which must have pointer type) uses the special 372 /// Swift asynchronous context-pointer ABI treatment. There can be at 373 /// most one parameter on a given function that uses this treatment. 374 SwiftAsyncContext, 375 }; 376 377 /// Assigned inheritance model for a class in the MS C++ ABI. Must match order 378 /// of spellings in MSInheritanceAttr. 379 enum class MSInheritanceModel { 380 Single = 0, 381 Multiple = 1, 382 Virtual = 2, 383 Unspecified = 3, 384 }; 385 386 llvm::StringRef getParameterABISpelling(ParameterABI kind); 387 388 inline llvm::StringRef getAccessSpelling(AccessSpecifier AS) { 389 switch (AS) { 390 case AccessSpecifier::AS_public: 391 return "public"; 392 case AccessSpecifier::AS_protected: 393 return "protected"; 394 case AccessSpecifier::AS_private: 395 return "private"; 396 case AccessSpecifier::AS_none: 397 return {}; 398 } 399 llvm_unreachable("Unknown AccessSpecifier"); 400 } 401 } // end namespace clang 402 403 #endif // LLVM_CLANG_BASIC_SPECIFIERS_H 404