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