1//===--- Builtins.h - Builtin function header -------------------*- 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 enum values for all the target-independent builtin 11/// functions. 12/// 13//===----------------------------------------------------------------------===// 14 15#ifndef LLVM_CLANG_BASIC_BUILTINS_H 16#define LLVM_CLANG_BASIC_BUILTINS_H 17 18#include "llvm/ADT/ArrayRef.h" 19#include <cstring> 20 21// VC++ defines 'alloca' as an object-like macro, which interferes with our 22// builtins. 23#undef alloca 24 25namespace clang { 26class TargetInfo; 27class IdentifierTable; 28class LangOptions; 29 30enum LanguageID { 31 GNU_LANG = 0x1, // builtin requires GNU mode. 32 C_LANG = 0x2, // builtin for c only. 33 CXX_LANG = 0x4, // builtin for cplusplus only. 34 OBJC_LANG = 0x8, // builtin for objective-c and objective-c++ 35 MS_LANG = 0x10, // builtin requires MS mode. 36 OCLC20_LANG = 0x20, // builtin for OpenCL C 2.0 only. 37 OCLC1X_LANG = 0x40, // builtin for OpenCL C 1.x only. 38 OMP_LANG = 0x80, // builtin requires OpenMP. 39 CUDA_LANG = 0x100, // builtin requires CUDA. 40 ALL_LANGUAGES = C_LANG | CXX_LANG | OBJC_LANG, // builtin for all languages. 41 ALL_GNU_LANGUAGES = ALL_LANGUAGES | GNU_LANG, // builtin requires GNU mode. 42 ALL_MS_LANGUAGES = ALL_LANGUAGES | MS_LANG, // builtin requires MS mode. 43 ALL_OCLC_LANGUAGES = OCLC1X_LANG | OCLC20_LANG // builtin for OCLC languages. 44}; 45 46namespace Builtin { 47enum ID { 48 NotBuiltin = 0, // This is not a builtin function. 49#define BUILTIN(ID, TYPE, ATTRS) BI##ID, 50#include "clang/Basic/Builtins.def" 51 FirstTSBuiltin 52}; 53 54struct Info { 55 const char *Name, *Type, *Attributes, *HeaderName; 56 LanguageID Langs; 57 const char *Features; 58}; 59 60/// Holds information about both target-independent and 61/// target-specific builtins, allowing easy queries by clients. 62/// 63/// Builtins from an optional auxiliary target are stored in 64/// AuxTSRecords. Their IDs are shifted up by TSRecords.size() and need to 65/// be translated back with getAuxBuiltinID() before use. 66class Context { 67 llvm::ArrayRef<Info> TSRecords; 68 llvm::ArrayRef<Info> AuxTSRecords; 69 70public: 71 Context() {} 72 73 /// Perform target-specific initialization 74 /// \param AuxTarget Target info to incorporate builtins from. May be nullptr. 75 void InitializeTarget(const TargetInfo &Target, const TargetInfo *AuxTarget); 76 77 /// Mark the identifiers for all the builtins with their 78 /// appropriate builtin ID # and mark any non-portable builtin identifiers as 79 /// such. 80 void initializeBuiltins(IdentifierTable &Table, const LangOptions& LangOpts); 81 82 /// Return the identifier name for the specified builtin, 83 /// e.g. "__builtin_abs". 84 const char *getName(unsigned ID) const { 85 return getRecord(ID).Name; 86 } 87 88 /// Get the type descriptor string for the specified builtin. 89 const char *getTypeString(unsigned ID) const { 90 return getRecord(ID).Type; 91 } 92 93 /// Return true if this function is a target-specific builtin. 94 bool isTSBuiltin(unsigned ID) const { 95 return ID >= Builtin::FirstTSBuiltin; 96 } 97 98 /// Return true if this function has no side effects. 99 bool isPure(unsigned ID) const { 100 return strchr(getRecord(ID).Attributes, 'U') != nullptr; 101 } 102 103 /// Return true if this function has no side effects and doesn't 104 /// read memory. 105 bool isConst(unsigned ID) const { 106 return strchr(getRecord(ID).Attributes, 'c') != nullptr; 107 } 108 109 /// Return true if we know this builtin never throws an exception. 110 bool isNoThrow(unsigned ID) const { 111 return strchr(getRecord(ID).Attributes, 'n') != nullptr; 112 } 113 114 /// Return true if we know this builtin never returns. 115 bool isNoReturn(unsigned ID) const { 116 return strchr(getRecord(ID).Attributes, 'r') != nullptr; 117 } 118 119 /// Return true if we know this builtin can return twice. 120 bool isReturnsTwice(unsigned ID) const { 121 return strchr(getRecord(ID).Attributes, 'j') != nullptr; 122 } 123 124 /// Returns true if this builtin does not perform the side-effects 125 /// of its arguments. 126 bool isUnevaluated(unsigned ID) const { 127 return strchr(getRecord(ID).Attributes, 'u') != nullptr; 128 } 129 130 /// Return true if this is a builtin for a libc/libm function, 131 /// with a "__builtin_" prefix (e.g. __builtin_abs). 132 bool isLibFunction(unsigned ID) const { 133 return strchr(getRecord(ID).Attributes, 'F') != nullptr; 134 } 135 136 /// Determines whether this builtin is a predefined libc/libm 137 /// function, such as "malloc", where we know the signature a 138 /// priori. 139 bool isPredefinedLibFunction(unsigned ID) const { 140 return strchr(getRecord(ID).Attributes, 'f') != nullptr; 141 } 142 143 /// Returns true if this builtin requires appropriate header in other 144 /// compilers. In Clang it will work even without including it, but we can emit 145 /// a warning about missing header. 146 bool isHeaderDependentFunction(unsigned ID) const { 147 return strchr(getRecord(ID).Attributes, 'h') != nullptr; 148 } 149 150 /// Determines whether this builtin is a predefined compiler-rt/libgcc 151 /// function, such as "__clear_cache", where we know the signature a 152 /// priori. 153 bool isPredefinedRuntimeFunction(unsigned ID) const { 154 return strchr(getRecord(ID).Attributes, 'i') != nullptr; 155 } 156 157 /// Determines whether this builtin has custom typechecking. 158 bool hasCustomTypechecking(unsigned ID) const { 159 return strchr(getRecord(ID).Attributes, 't') != nullptr; 160 } 161 162 /// Determines whether a declaration of this builtin should be recognized 163 /// even if the type doesn't match the specified signature. 164 bool allowTypeMismatch(unsigned ID) const { 165 return strchr(getRecord(ID).Attributes, 'T') != nullptr || 166 hasCustomTypechecking(ID); 167 } 168 169 /// Determines whether this builtin has a result or any arguments which 170 /// are pointer types. 171 bool hasPtrArgsOrResult(unsigned ID) const { 172 return strchr(getRecord(ID).Type, '*') != nullptr; 173 } 174 175 /// Return true if this builtin has a result or any arguments which are 176 /// reference types. 177 bool hasReferenceArgsOrResult(unsigned ID) const { 178 return strchr(getRecord(ID).Type, '&') != nullptr || 179 strchr(getRecord(ID).Type, 'A') != nullptr; 180 } 181 182 /// If this is a library function that comes from a specific 183 /// header, retrieve that header name. 184 const char *getHeaderName(unsigned ID) const { 185 return getRecord(ID).HeaderName; 186 } 187 188 /// Determine whether this builtin is like printf in its 189 /// formatting rules and, if so, set the index to the format string 190 /// argument and whether this function as a va_list argument. 191 bool isPrintfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg); 192 193 /// Determine whether this builtin is like scanf in its 194 /// formatting rules and, if so, set the index to the format string 195 /// argument and whether this function as a va_list argument. 196 bool isScanfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg); 197 198 /// Determine whether this builtin has callback behavior (see 199 /// llvm::AbstractCallSites for details). If so, add the index to the 200 /// callback callee argument and the callback payload arguments. 201 bool performsCallback(unsigned ID, 202 llvm::SmallVectorImpl<int> &Encoding) const; 203 204 /// Return true if this function has no side effects and doesn't 205 /// read memory, except for possibly errno. 206 /// 207 /// Such functions can be const when the MathErrno lang option is disabled. 208 bool isConstWithoutErrno(unsigned ID) const { 209 return strchr(getRecord(ID).Attributes, 'e') != nullptr; 210 } 211 212 const char *getRequiredFeatures(unsigned ID) const { 213 return getRecord(ID).Features; 214 } 215 216 unsigned getRequiredVectorWidth(unsigned ID) const; 217 218 /// Return true if builtin ID belongs to AuxTarget. 219 bool isAuxBuiltinID(unsigned ID) const { 220 return ID >= (Builtin::FirstTSBuiltin + TSRecords.size()); 221 } 222 223 /// Return real builtin ID (i.e. ID it would have during compilation 224 /// for AuxTarget). 225 unsigned getAuxBuiltinID(unsigned ID) const { return ID - TSRecords.size(); } 226 227 /// Returns true if this is a libc/libm function without the '__builtin_' 228 /// prefix. 229 static bool isBuiltinFunc(llvm::StringRef Name); 230 231 /// Returns true if this is a builtin that can be redeclared. Returns true 232 /// for non-builtins. 233 bool canBeRedeclared(unsigned ID) const; 234 235private: 236 const Info &getRecord(unsigned ID) const; 237 238 /// Is this builtin supported according to the given language options? 239 bool builtinIsSupported(const Builtin::Info &BuiltinInfo, 240 const LangOptions &LangOpts); 241 242 /// Helper function for isPrintfLike and isScanfLike. 243 bool isLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg, 244 const char *Fmt) const; 245}; 246 247} 248 249/// Kinds of BuiltinTemplateDecl. 250enum BuiltinTemplateKind : int { 251 /// This names the __make_integer_seq BuiltinTemplateDecl. 252 BTK__make_integer_seq, 253 254 /// This names the __type_pack_element BuiltinTemplateDecl. 255 BTK__type_pack_element 256}; 257 258} // end namespace clang 259#endif 260