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