1 //===--- Builtins.h - Builtin function header -------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 /// 10 /// \file 11 /// \brief Defines enum values for all the target-independent builtin 12 /// functions. 13 /// 14 //===----------------------------------------------------------------------===// 15 16 #ifndef LLVM_CLANG_BASIC_BUILTINS_H 17 #define LLVM_CLANG_BASIC_BUILTINS_H 18 19 #include "clang/Basic/LLVM.h" 20 #include <cstring> 21 22 // VC++ defines 'alloca' as an object-like macro, which interferes with our 23 // builtins. 24 #undef alloca 25 26 namespace clang { 27 class TargetInfo; 28 class IdentifierTable; 29 class ASTContext; 30 class QualType; 31 class LangOptions; 32 33 enum LanguageID { 34 GNU_LANG = 0x1, // builtin requires GNU mode. 35 C_LANG = 0x2, // builtin for c only. 36 CXX_LANG = 0x4, // builtin for cplusplus only. 37 OBJC_LANG = 0x8, // builtin for objective-c and objective-c++ 38 MS_LANG = 0x10, // builtin requires MS mode. 39 ALL_LANGUAGES = C_LANG | CXX_LANG | OBJC_LANG, // builtin for all languages. 40 ALL_GNU_LANGUAGES = ALL_LANGUAGES | GNU_LANG, // builtin requires GNU mode. 41 ALL_MS_LANGUAGES = ALL_LANGUAGES | MS_LANG // builtin requires MS mode. 42 }; 43 44 namespace Builtin { 45 enum ID { 46 NotBuiltin = 0, // This is not a builtin function. 47 #define BUILTIN(ID, TYPE, ATTRS) BI##ID, 48 #include "clang/Basic/Builtins.def" 49 FirstTSBuiltin 50 }; 51 52 struct Info { 53 const char *Name, *Type, *Attributes, *HeaderName; 54 LanguageID builtin_lang; 55 56 bool operator==(const Info &RHS) const { 57 return !strcmp(Name, RHS.Name) && 58 !strcmp(Type, RHS.Type) && 59 !strcmp(Attributes, RHS.Attributes); 60 } 61 bool operator!=(const Info &RHS) const { return !(*this == RHS); } 62 }; 63 64 /// \brief Holds information about both target-independent and 65 /// target-specific builtins, allowing easy queries by clients. 66 class Context { 67 const Info *TSRecords; 68 unsigned NumTSRecords; 69 public: 70 Context(); 71 72 /// \brief Perform target-specific initialization 73 void InitializeTarget(const TargetInfo &Target); 74 75 /// \brief Mark the identifiers for all the builtins with their 76 /// appropriate builtin ID # and mark any non-portable builtin identifiers as 77 /// such. 78 void InitializeBuiltins(IdentifierTable &Table, const LangOptions& LangOpts); 79 80 /// \brief Populate the vector with the names of all of the builtins. 81 void GetBuiltinNames(SmallVectorImpl<const char *> &Names); 82 83 /// \brief Return the identifier name for the specified builtin, 84 /// e.g. "__builtin_abs". 85 const char *GetName(unsigned ID) const { 86 return GetRecord(ID).Name; 87 } 88 89 /// \brief Get the type descriptor string for the specified builtin. 90 const char *GetTypeString(unsigned ID) const { 91 return GetRecord(ID).Type; 92 } 93 94 /// \brief Return true if this function has no side effects and doesn't 95 /// read memory. 96 bool isConst(unsigned ID) const { 97 return strchr(GetRecord(ID).Attributes, 'c') != nullptr; 98 } 99 100 /// \brief Return true if we know this builtin never throws an exception. 101 bool isNoThrow(unsigned ID) const { 102 return strchr(GetRecord(ID).Attributes, 'n') != nullptr; 103 } 104 105 /// \brief Return true if we know this builtin never returns. 106 bool isNoReturn(unsigned ID) const { 107 return strchr(GetRecord(ID).Attributes, 'r') != nullptr; 108 } 109 110 /// \brief Return true if we know this builtin can return twice. 111 bool isReturnsTwice(unsigned ID) const { 112 return strchr(GetRecord(ID).Attributes, 'j') != nullptr; 113 } 114 115 /// \brief Returns true if this builtin does not perform the side-effects 116 /// of its arguments. 117 bool isUnevaluated(unsigned ID) const { 118 return strchr(GetRecord(ID).Attributes, 'u') != nullptr; 119 } 120 121 /// \brief Return true if this is a builtin for a libc/libm function, 122 /// with a "__builtin_" prefix (e.g. __builtin_abs). 123 bool isLibFunction(unsigned ID) const { 124 return strchr(GetRecord(ID).Attributes, 'F') != nullptr; 125 } 126 127 /// \brief Determines whether this builtin is a predefined libc/libm 128 /// function, such as "malloc", where we know the signature a 129 /// priori. 130 bool isPredefinedLibFunction(unsigned ID) const { 131 return strchr(GetRecord(ID).Attributes, 'f') != nullptr; 132 } 133 134 /// \brief Determines whether this builtin is a predefined compiler-rt/libgcc 135 /// function, such as "__clear_cache", where we know the signature a 136 /// priori. 137 bool isPredefinedRuntimeFunction(unsigned ID) const { 138 return strchr(GetRecord(ID).Attributes, 'i') != nullptr; 139 } 140 141 /// \brief Determines whether this builtin has custom typechecking. 142 bool hasCustomTypechecking(unsigned ID) const { 143 return strchr(GetRecord(ID).Attributes, 't') != nullptr; 144 } 145 146 /// \brief Completely forget that the given ID was ever considered a builtin, 147 /// e.g., because the user provided a conflicting signature. 148 void ForgetBuiltin(unsigned ID, IdentifierTable &Table); 149 150 /// \brief If this is a library function that comes from a specific 151 /// header, retrieve that header name. 152 const char *getHeaderName(unsigned ID) const { 153 return GetRecord(ID).HeaderName; 154 } 155 156 /// \brief Determine whether this builtin is like printf in its 157 /// formatting rules and, if so, set the index to the format string 158 /// argument and whether this function as a va_list argument. 159 bool isPrintfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg); 160 161 /// \brief Determine whether this builtin is like scanf in its 162 /// formatting rules and, if so, set the index to the format string 163 /// argument and whether this function as a va_list argument. 164 bool isScanfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg); 165 166 /// \brief Return true if this function has no side effects and doesn't 167 /// read memory, except for possibly errno. 168 /// 169 /// Such functions can be const when the MathErrno lang option is disabled. 170 bool isConstWithoutErrno(unsigned ID) const { 171 return strchr(GetRecord(ID).Attributes, 'e') != nullptr; 172 } 173 174 private: 175 const Info &GetRecord(unsigned ID) const; 176 177 /// \brief Is this builtin supported according to the given language options? 178 bool BuiltinIsSupported(const Builtin::Info &BuiltinInfo, 179 const LangOptions &LangOpts); 180 181 /// \brief Helper function for isPrintfLike and isScanfLike. 182 bool isLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg, 183 const char *Fmt) const; 184 }; 185 186 } 187 } // end namespace clang 188 #endif 189
