clang  3.9.0
Builtins.h
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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 "llvm/ADT/ArrayRef.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  OCLC20_LANG = 0x20, // builtin for OpenCL C only.
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 };
44 
45 namespace Builtin {
46 enum ID {
47  NotBuiltin = 0, // This is not a builtin function.
48 #define BUILTIN(ID, TYPE, ATTRS) BI##ID,
49 #include "clang/Basic/Builtins.def"
51 };
52 
53 struct Info {
54  const char *Name, *Type, *Attributes, *HeaderName;
56  const char *Features;
57 };
58 
59 /// \brief Holds information about both target-independent and
60 /// target-specific builtins, allowing easy queries by clients.
61 ///
62 /// Builtins from an optional auxiliary target are stored in
63 /// AuxTSRecords. Their IDs are shifted up by TSRecords.size() and need to
64 /// be translated back with getAuxBuiltinID() before use.
65 class Context {
66  llvm::ArrayRef<Info> TSRecords;
67  llvm::ArrayRef<Info> AuxTSRecords;
68 
69 public:
70  Context() {}
71 
72  /// \brief Perform target-specific initialization
73  /// \param AuxTarget Target info to incorporate builtins from. May be nullptr.
74  void InitializeTarget(const TargetInfo &Target, const TargetInfo *AuxTarget);
75 
76  /// \brief Mark the identifiers for all the builtins with their
77  /// appropriate builtin ID # and mark any non-portable builtin identifiers as
78  /// such.
79  void initializeBuiltins(IdentifierTable &Table, const LangOptions& LangOpts);
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 is a target-specific builtin.
93  bool isTSBuiltin(unsigned ID) const {
94  return ID >= Builtin::FirstTSBuiltin;
95  }
96 
97  /// \brief Return true if this function has no side effects.
98  bool isPure(unsigned ID) const {
99  return strchr(getRecord(ID).Attributes, 'U') != nullptr;
100  }
101 
102  /// \brief Return true if this function has no side effects and doesn't
103  /// read memory.
104  bool isConst(unsigned ID) const {
105  return strchr(getRecord(ID).Attributes, 'c') != nullptr;
106  }
107 
108  /// \brief Return true if we know this builtin never throws an exception.
109  bool isNoThrow(unsigned ID) const {
110  return strchr(getRecord(ID).Attributes, 'n') != nullptr;
111  }
112 
113  /// \brief Return true if we know this builtin never returns.
114  bool isNoReturn(unsigned ID) const {
115  return strchr(getRecord(ID).Attributes, 'r') != nullptr;
116  }
117 
118  /// \brief Return true if we know this builtin can return twice.
119  bool isReturnsTwice(unsigned ID) const {
120  return strchr(getRecord(ID).Attributes, 'j') != nullptr;
121  }
122 
123  /// \brief Returns true if this builtin does not perform the side-effects
124  /// of its arguments.
125  bool isUnevaluated(unsigned ID) const {
126  return strchr(getRecord(ID).Attributes, 'u') != nullptr;
127  }
128 
129  /// \brief Return true if this is a builtin for a libc/libm function,
130  /// with a "__builtin_" prefix (e.g. __builtin_abs).
131  bool isLibFunction(unsigned ID) const {
132  return strchr(getRecord(ID).Attributes, 'F') != nullptr;
133  }
134 
135  /// \brief Determines whether this builtin is a predefined libc/libm
136  /// function, such as "malloc", where we know the signature a
137  /// priori.
138  bool isPredefinedLibFunction(unsigned ID) const {
139  return strchr(getRecord(ID).Attributes, 'f') != nullptr;
140  }
141 
142  /// \brief Determines whether this builtin is a predefined compiler-rt/libgcc
143  /// function, such as "__clear_cache", where we know the signature a
144  /// priori.
145  bool isPredefinedRuntimeFunction(unsigned ID) const {
146  return strchr(getRecord(ID).Attributes, 'i') != nullptr;
147  }
148 
149  /// \brief Determines whether this builtin has custom typechecking.
150  bool hasCustomTypechecking(unsigned ID) const {
151  return strchr(getRecord(ID).Attributes, 't') != nullptr;
152  }
153 
154  /// \brief Determines whether this builtin has a result or any arguments which
155  /// are pointer types.
156  bool hasPtrArgsOrResult(unsigned ID) const {
157  return strchr(getRecord(ID).Type, '*') != nullptr;
158  }
159 
160  /// \brief Completely forget that the given ID was ever considered a builtin,
161  /// e.g., because the user provided a conflicting signature.
162  void forgetBuiltin(unsigned ID, IdentifierTable &Table);
163 
164  /// \brief If this is a library function that comes from a specific
165  /// header, retrieve that header name.
166  const char *getHeaderName(unsigned ID) const {
167  return getRecord(ID).HeaderName;
168  }
169 
170  /// \brief Determine whether this builtin is like printf in its
171  /// formatting rules and, if so, set the index to the format string
172  /// argument and whether this function as a va_list argument.
173  bool isPrintfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg);
174 
175  /// \brief Determine whether this builtin is like scanf in its
176  /// formatting rules and, if so, set the index to the format string
177  /// argument and whether this function as a va_list argument.
178  bool isScanfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg);
179 
180  /// \brief Return true if this function has no side effects and doesn't
181  /// read memory, except for possibly errno.
182  ///
183  /// Such functions can be const when the MathErrno lang option is disabled.
184  bool isConstWithoutErrno(unsigned ID) const {
185  return strchr(getRecord(ID).Attributes, 'e') != nullptr;
186  }
187 
188  const char *getRequiredFeatures(unsigned ID) const {
189  return getRecord(ID).Features;
190  }
191 
192  /// \brief Return true if builtin ID belongs to AuxTarget.
193  bool isAuxBuiltinID(unsigned ID) const {
194  return ID >= (Builtin::FirstTSBuiltin + TSRecords.size());
195  }
196 
197  /// Return real buitin ID (i.e. ID it would have furing compilation
198  /// for AuxTarget).
199  unsigned getAuxBuiltinID(unsigned ID) const { return ID - TSRecords.size(); }
200 
201  /// Returns true if this is a libc/libm function without the '__builtin_'
202  /// prefix.
203  static bool isBuiltinFunc(const char *Name);
204 
205 private:
206  const Info &getRecord(unsigned ID) const;
207 
208  /// \brief Is this builtin supported according to the given language options?
209  bool builtinIsSupported(const Builtin::Info &BuiltinInfo,
210  const LangOptions &LangOpts);
211 
212  /// \brief Helper function for isPrintfLike and isScanfLike.
213  bool isLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg,
214  const char *Fmt) const;
215 };
216 
217 }
218 
219 /// \brief Kinds of BuiltinTemplateDecl.
221  /// \brief This names the __make_integer_seq BuiltinTemplateDecl.
223 
224  /// \brief This names the __type_pack_element BuiltinTemplateDecl.
226 };
227 
228 } // end namespace clang
229 #endif
Holds information about both target-independent and target-specific builtins, allowing easy queries b...
Definition: Builtins.h:65
const char * Attributes
Definition: Builtins.h:54
bool isNoReturn(unsigned ID) const
Return true if we know this builtin never returns.
Definition: Builtins.h:114
static const Builtin::Info BuiltinInfo[]
Definition: Builtins.cpp:21
static bool isBuiltinFunc(const char *Name)
Returns true if this is a libc/libm function without the '__builtin_' prefix.
Definition: Builtins.cpp:51
void forgetBuiltin(unsigned ID, IdentifierTable &Table)
Completely forget that the given ID was ever considered a builtin, e.g., because the user provided a ...
Definition: Builtins.cpp:100
bool isPredefinedLibFunction(unsigned ID) const
Determines whether this builtin is a predefined libc/libm function, such as "malloc", where we know the signature a priori.
Definition: Builtins.h:138
bool isPrintfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg)
Determine whether this builtin is like printf in its formatting rules and, if so, set the index to th...
Definition: Builtins.cpp:127
The base class of the type hierarchy.
Definition: Type.h:1281
const char * Name
Definition: Builtins.h:54
bool isAuxBuiltinID(unsigned ID) const
Return true if builtin ID belongs to AuxTarget.
Definition: Builtins.h:193
bool hasPtrArgsOrResult(unsigned ID) const
Determines whether this builtin has a result or any arguments which are pointer types.
Definition: Builtins.h:156
class LLVM_ALIGNAS(8) DependentTemplateSpecializationType const IdentifierInfo * Name
Represents a template specialization type whose template cannot be resolved, e.g. ...
Definition: Type.h:4549
bool isUnevaluated(unsigned ID) const
Returns true if this builtin does not perform the side-effects of its arguments.
Definition: Builtins.h:125
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:48
const char * getTypeString(unsigned ID) const
Get the type descriptor string for the specified builtin.
Definition: Builtins.h:88
const char * getHeaderName(unsigned ID) const
If this is a library function that comes from a specific header, retrieve that header name...
Definition: Builtins.h:166
LanguageID Langs
Definition: Builtins.h:55
const char * Type
Definition: Builtins.h:54
bool isReturnsTwice(unsigned ID) const
Return true if we know this builtin can return twice.
Definition: Builtins.h:119
bool isPure(unsigned ID) const
Return true if this function has no side effects.
Definition: Builtins.h:98
Exposes information about the current target.
bool isNoThrow(unsigned ID) const
Return true if we know this builtin never throws an exception.
Definition: Builtins.h:109
friend class ASTContext
Definition: Type.h:4178
const char * getName(unsigned ID) const
Return the identifier name for the specified builtin, e.g.
Definition: Builtins.h:83
Implements an efficient mapping from strings to IdentifierInfo nodes.
bool hasCustomTypechecking(unsigned ID) const
Determines whether this builtin has custom typechecking.
Definition: Builtins.h:150
const char * HeaderName
Definition: Builtins.h:54
bool isConst(unsigned ID) const
Return true if this function has no side effects and doesn't read memory.
Definition: Builtins.h:104
bool isPredefinedRuntimeFunction(unsigned ID) const
Determines whether this builtin is a predefined compiler-rt/libgcc function, such as "__clear_cache"...
Definition: Builtins.h:145
This names the __make_integer_seq BuiltinTemplateDecl.
Definition: Builtins.h:222
const char * getRequiredFeatures(unsigned ID) const
Definition: Builtins.h:188
bool isConstWithoutErrno(unsigned ID) const
Return true if this function has no side effects and doesn't read memory, except for possibly errno...
Definition: Builtins.h:184
void initializeBuiltins(IdentifierTable &Table, const LangOptions &LangOpts)
Mark the identifiers for all the builtins with their appropriate builtin ID # and mark any non-portab...
Definition: Builtins.cpp:81
unsigned getAuxBuiltinID(unsigned ID) const
Return real buitin ID (i.e.
Definition: Builtins.h:199
BuiltinTemplateKind
Kinds of BuiltinTemplateDecl.
Definition: Builtins.h:220
bool isScanfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg)
Determine whether this builtin is like scanf in its formatting rules and, if so, set the index to the...
Definition: Builtins.cpp:132
bool isTSBuiltin(unsigned ID) const
Return true if this function is a target-specific builtin.
Definition: Builtins.h:93
This names the __type_pack_element BuiltinTemplateDecl.
Definition: Builtins.h:225
bool isLibFunction(unsigned ID) const
Return true if this is a builtin for a libc/libm function, with a "__builtin_" prefix (e...
Definition: Builtins.h:131
const char * Features
Definition: Builtins.h:56
void InitializeTarget(const TargetInfo &Target, const TargetInfo *AuxTarget)
Perform target-specific initialization.
Definition: Builtins.cpp:43
LanguageID
Definition: Builtins.h:33