xref: /llvm-project/clang/lib/Frontend/InitPreprocessor.cpp (revision 2afb63c0010ae69eefb34ce5926dcec21934e394)
1 //===--- InitPreprocessor.cpp - PP initialization code. ---------*- 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 // This file implements the clang::InitializePreprocessor function.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/Frontend/Utils.h"
15 #include "clang/Basic/FileManager.h"
16 #include "clang/Basic/MacroBuilder.h"
17 #include "clang/Basic/SourceManager.h"
18 #include "clang/Basic/TargetInfo.h"
19 #include "clang/Basic/Version.h"
20 #include "clang/Frontend/FrontendDiagnostic.h"
21 #include "clang/Frontend/FrontendOptions.h"
22 #include "clang/Lex/HeaderSearch.h"
23 #include "clang/Lex/Preprocessor.h"
24 #include "clang/Lex/PreprocessorOptions.h"
25 #include "clang/Serialization/ASTReader.h"
26 #include "llvm/ADT/APFloat.h"
27 #include "llvm/Support/FileSystem.h"
28 #include "llvm/Support/MemoryBuffer.h"
29 #include "llvm/Support/Path.h"
30 using namespace clang;
31 
32 static bool MacroBodyEndsInBackslash(StringRef MacroBody) {
33   while (!MacroBody.empty() && isWhitespace(MacroBody.back()))
34     MacroBody = MacroBody.drop_back();
35   return !MacroBody.empty() && MacroBody.back() == '\\';
36 }
37 
38 // Append a #define line to Buf for Macro.  Macro should be of the form XXX,
39 // in which case we emit "#define XXX 1" or "XXX=Y z W" in which case we emit
40 // "#define XXX Y z W".  To get a #define with no value, use "XXX=".
41 static void DefineBuiltinMacro(MacroBuilder &Builder, StringRef Macro,
42                                DiagnosticsEngine &Diags) {
43   std::pair<StringRef, StringRef> MacroPair = Macro.split('=');
44   StringRef MacroName = MacroPair.first;
45   StringRef MacroBody = MacroPair.second;
46   if (MacroName.size() != Macro.size()) {
47     // Per GCC -D semantics, the macro ends at \n if it exists.
48     StringRef::size_type End = MacroBody.find_first_of("\n\r");
49     if (End != StringRef::npos)
50       Diags.Report(diag::warn_fe_macro_contains_embedded_newline)
51         << MacroName;
52     MacroBody = MacroBody.substr(0, End);
53     // We handle macro bodies which end in a backslash by appending an extra
54     // backslash+newline.  This makes sure we don't accidentally treat the
55     // backslash as a line continuation marker.
56     if (MacroBodyEndsInBackslash(MacroBody))
57       Builder.defineMacro(MacroName, Twine(MacroBody) + "\\\n");
58     else
59       Builder.defineMacro(MacroName, MacroBody);
60   } else {
61     // Push "macroname 1".
62     Builder.defineMacro(Macro);
63   }
64 }
65 
66 /// AddImplicitInclude - Add an implicit \#include of the specified file to the
67 /// predefines buffer.
68 static void AddImplicitInclude(MacroBuilder &Builder, StringRef File,
69                                FileManager &FileMgr) {
70   Builder.append(Twine("#include \"") +
71                  HeaderSearch::NormalizeDashIncludePath(File, FileMgr) + "\"");
72 }
73 
74 static void AddImplicitIncludeMacros(MacroBuilder &Builder,
75                                      StringRef File,
76                                      FileManager &FileMgr) {
77   Builder.append(Twine("#__include_macros \"") +
78                  HeaderSearch::NormalizeDashIncludePath(File, FileMgr) + "\"");
79   // Marker token to stop the __include_macros fetch loop.
80   Builder.append("##"); // ##?
81 }
82 
83 /// AddImplicitIncludePTH - Add an implicit \#include using the original file
84 /// used to generate a PTH cache.
85 static void AddImplicitIncludePTH(MacroBuilder &Builder, Preprocessor &PP,
86                                   StringRef ImplicitIncludePTH) {
87   PTHManager *P = PP.getPTHManager();
88   // Null check 'P' in the corner case where it couldn't be created.
89   const char *OriginalFile = P ? P->getOriginalSourceFile() : 0;
90 
91   if (!OriginalFile) {
92     PP.getDiagnostics().Report(diag::err_fe_pth_file_has_no_source_header)
93       << ImplicitIncludePTH;
94     return;
95   }
96 
97   AddImplicitInclude(Builder, OriginalFile, PP.getFileManager());
98 }
99 
100 /// \brief Add an implicit \#include using the original file used to generate
101 /// a PCH file.
102 static void AddImplicitIncludePCH(MacroBuilder &Builder, Preprocessor &PP,
103                                   StringRef ImplicitIncludePCH) {
104   std::string OriginalFile =
105     ASTReader::getOriginalSourceFile(ImplicitIncludePCH, PP.getFileManager(),
106                                      PP.getDiagnostics());
107   if (OriginalFile.empty())
108     return;
109 
110   AddImplicitInclude(Builder, OriginalFile, PP.getFileManager());
111 }
112 
113 /// PickFP - This is used to pick a value based on the FP semantics of the
114 /// specified FP model.
115 template <typename T>
116 static T PickFP(const llvm::fltSemantics *Sem, T IEEESingleVal,
117                 T IEEEDoubleVal, T X87DoubleExtendedVal, T PPCDoubleDoubleVal,
118                 T IEEEQuadVal) {
119   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEsingle)
120     return IEEESingleVal;
121   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEdouble)
122     return IEEEDoubleVal;
123   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::x87DoubleExtended)
124     return X87DoubleExtendedVal;
125   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::PPCDoubleDouble)
126     return PPCDoubleDoubleVal;
127   assert(Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEquad);
128   return IEEEQuadVal;
129 }
130 
131 static void DefineFloatMacros(MacroBuilder &Builder, StringRef Prefix,
132                               const llvm::fltSemantics *Sem, StringRef Ext) {
133   const char *DenormMin, *Epsilon, *Max, *Min;
134   DenormMin = PickFP(Sem, "1.40129846e-45", "4.9406564584124654e-324",
135                      "3.64519953188247460253e-4951",
136                      "4.94065645841246544176568792868221e-324",
137                      "6.47517511943802511092443895822764655e-4966");
138   int Digits = PickFP(Sem, 6, 15, 18, 31, 33);
139   Epsilon = PickFP(Sem, "1.19209290e-7", "2.2204460492503131e-16",
140                    "1.08420217248550443401e-19",
141                    "4.94065645841246544176568792868221e-324",
142                    "1.92592994438723585305597794258492732e-34");
143   int MantissaDigits = PickFP(Sem, 24, 53, 64, 106, 113);
144   int Min10Exp = PickFP(Sem, -37, -307, -4931, -291, -4931);
145   int Max10Exp = PickFP(Sem, 38, 308, 4932, 308, 4932);
146   int MinExp = PickFP(Sem, -125, -1021, -16381, -968, -16381);
147   int MaxExp = PickFP(Sem, 128, 1024, 16384, 1024, 16384);
148   Min = PickFP(Sem, "1.17549435e-38", "2.2250738585072014e-308",
149                "3.36210314311209350626e-4932",
150                "2.00416836000897277799610805135016e-292",
151                "3.36210314311209350626267781732175260e-4932");
152   Max = PickFP(Sem, "3.40282347e+38", "1.7976931348623157e+308",
153                "1.18973149535723176502e+4932",
154                "1.79769313486231580793728971405301e+308",
155                "1.18973149535723176508575932662800702e+4932");
156 
157   SmallString<32> DefPrefix;
158   DefPrefix = "__";
159   DefPrefix += Prefix;
160   DefPrefix += "_";
161 
162   Builder.defineMacro(DefPrefix + "DENORM_MIN__", Twine(DenormMin)+Ext);
163   Builder.defineMacro(DefPrefix + "HAS_DENORM__");
164   Builder.defineMacro(DefPrefix + "DIG__", Twine(Digits));
165   Builder.defineMacro(DefPrefix + "EPSILON__", Twine(Epsilon)+Ext);
166   Builder.defineMacro(DefPrefix + "HAS_INFINITY__");
167   Builder.defineMacro(DefPrefix + "HAS_QUIET_NAN__");
168   Builder.defineMacro(DefPrefix + "MANT_DIG__", Twine(MantissaDigits));
169 
170   Builder.defineMacro(DefPrefix + "MAX_10_EXP__", Twine(Max10Exp));
171   Builder.defineMacro(DefPrefix + "MAX_EXP__", Twine(MaxExp));
172   Builder.defineMacro(DefPrefix + "MAX__", Twine(Max)+Ext);
173 
174   Builder.defineMacro(DefPrefix + "MIN_10_EXP__","("+Twine(Min10Exp)+")");
175   Builder.defineMacro(DefPrefix + "MIN_EXP__", "("+Twine(MinExp)+")");
176   Builder.defineMacro(DefPrefix + "MIN__", Twine(Min)+Ext);
177 }
178 
179 
180 /// DefineTypeSize - Emit a macro to the predefines buffer that declares a macro
181 /// named MacroName with the max value for a type with width 'TypeWidth' a
182 /// signedness of 'isSigned' and with a value suffix of 'ValSuffix' (e.g. LL).
183 static void DefineTypeSize(StringRef MacroName, unsigned TypeWidth,
184                            StringRef ValSuffix, bool isSigned,
185                            MacroBuilder &Builder) {
186   llvm::APInt MaxVal = isSigned ? llvm::APInt::getSignedMaxValue(TypeWidth)
187                                 : llvm::APInt::getMaxValue(TypeWidth);
188   Builder.defineMacro(MacroName, MaxVal.toString(10, isSigned) + ValSuffix);
189 }
190 
191 /// DefineTypeSize - An overloaded helper that uses TargetInfo to determine
192 /// the width, suffix, and signedness of the given type
193 static void DefineTypeSize(StringRef MacroName, TargetInfo::IntType Ty,
194                            const TargetInfo &TI, MacroBuilder &Builder) {
195   DefineTypeSize(MacroName, TI.getTypeWidth(Ty), TI.getTypeConstantSuffix(Ty),
196                  TI.isTypeSigned(Ty), Builder);
197 }
198 
199 static void DefineType(const Twine &MacroName, TargetInfo::IntType Ty,
200                        MacroBuilder &Builder) {
201   Builder.defineMacro(MacroName, TargetInfo::getTypeName(Ty));
202 }
203 
204 static void DefineTypeWidth(StringRef MacroName, TargetInfo::IntType Ty,
205                             const TargetInfo &TI, MacroBuilder &Builder) {
206   Builder.defineMacro(MacroName, Twine(TI.getTypeWidth(Ty)));
207 }
208 
209 static void DefineTypeSizeof(StringRef MacroName, unsigned BitWidth,
210                              const TargetInfo &TI, MacroBuilder &Builder) {
211   Builder.defineMacro(MacroName,
212                       Twine(BitWidth / TI.getCharWidth()));
213 }
214 
215 static void DefineExactWidthIntType(TargetInfo::IntType Ty,
216                                const TargetInfo &TI, MacroBuilder &Builder) {
217   int TypeWidth = TI.getTypeWidth(Ty);
218 
219   // Use the target specified int64 type, when appropriate, so that [u]int64_t
220   // ends up being defined in terms of the correct type.
221   if (TypeWidth == 64)
222     Ty = TI.getInt64Type();
223 
224   DefineType("__INT" + Twine(TypeWidth) + "_TYPE__", Ty, Builder);
225 
226   StringRef ConstSuffix(TargetInfo::getTypeConstantSuffix(Ty));
227   if (!ConstSuffix.empty())
228     Builder.defineMacro("__INT" + Twine(TypeWidth) + "_C_SUFFIX__",
229                         ConstSuffix);
230 }
231 
232 /// Get the value the ATOMIC_*_LOCK_FREE macro should have for a type with
233 /// the specified properties.
234 static const char *getLockFreeValue(unsigned TypeWidth, unsigned TypeAlign,
235                                     unsigned InlineWidth) {
236   // Fully-aligned, power-of-2 sizes no larger than the inline
237   // width will be inlined as lock-free operations.
238   if (TypeWidth == TypeAlign && (TypeWidth & (TypeWidth - 1)) == 0 &&
239       TypeWidth <= InlineWidth)
240     return "2"; // "always lock free"
241   // We cannot be certain what operations the lib calls might be
242   // able to implement as lock-free on future processors.
243   return "1"; // "sometimes lock free"
244 }
245 
246 /// \brief Add definitions required for a smooth interaction between
247 /// Objective-C++ automated reference counting and libstdc++ (4.2).
248 static void AddObjCXXARCLibstdcxxDefines(const LangOptions &LangOpts,
249                                          MacroBuilder &Builder) {
250   Builder.defineMacro("_GLIBCXX_PREDEFINED_OBJC_ARC_IS_SCALAR");
251 
252   std::string Result;
253   {
254     // Provide specializations for the __is_scalar type trait so that
255     // lifetime-qualified objects are not considered "scalar" types, which
256     // libstdc++ uses as an indicator of the presence of trivial copy, assign,
257     // default-construct, and destruct semantics (none of which hold for
258     // lifetime-qualified objects in ARC).
259     llvm::raw_string_ostream Out(Result);
260 
261     Out << "namespace std {\n"
262         << "\n"
263         << "struct __true_type;\n"
264         << "struct __false_type;\n"
265         << "\n";
266 
267     Out << "template<typename _Tp> struct __is_scalar;\n"
268         << "\n";
269 
270     Out << "template<typename _Tp>\n"
271         << "struct __is_scalar<__attribute__((objc_ownership(strong))) _Tp> {\n"
272         << "  enum { __value = 0 };\n"
273         << "  typedef __false_type __type;\n"
274         << "};\n"
275         << "\n";
276 
277     if (LangOpts.ObjCARCWeak) {
278       Out << "template<typename _Tp>\n"
279           << "struct __is_scalar<__attribute__((objc_ownership(weak))) _Tp> {\n"
280           << "  enum { __value = 0 };\n"
281           << "  typedef __false_type __type;\n"
282           << "};\n"
283           << "\n";
284     }
285 
286     Out << "template<typename _Tp>\n"
287         << "struct __is_scalar<__attribute__((objc_ownership(autoreleasing)))"
288         << " _Tp> {\n"
289         << "  enum { __value = 0 };\n"
290         << "  typedef __false_type __type;\n"
291         << "};\n"
292         << "\n";
293 
294     Out << "}\n";
295   }
296   Builder.append(Result);
297 }
298 
299 static void InitializeStandardPredefinedMacros(const TargetInfo &TI,
300                                                const LangOptions &LangOpts,
301                                                const FrontendOptions &FEOpts,
302                                                MacroBuilder &Builder) {
303   if (!LangOpts.MicrosoftMode && !LangOpts.TraditionalCPP)
304     Builder.defineMacro("__STDC__");
305   if (LangOpts.Freestanding)
306     Builder.defineMacro("__STDC_HOSTED__", "0");
307   else
308     Builder.defineMacro("__STDC_HOSTED__");
309 
310   if (!LangOpts.CPlusPlus) {
311     if (LangOpts.C11)
312       Builder.defineMacro("__STDC_VERSION__", "201112L");
313     else if (LangOpts.C99)
314       Builder.defineMacro("__STDC_VERSION__", "199901L");
315     else if (!LangOpts.GNUMode && LangOpts.Digraphs)
316       Builder.defineMacro("__STDC_VERSION__", "199409L");
317   } else {
318     // FIXME: Use the right value for __cplusplus for C++1y once one is chosen.
319     if (LangOpts.CPlusPlus1y)
320       Builder.defineMacro("__cplusplus", "201305L");
321     // C++11 [cpp.predefined]p1:
322     //   The name __cplusplus is defined to the value 201103L when compiling a
323     //   C++ translation unit.
324     else if (LangOpts.CPlusPlus11)
325       Builder.defineMacro("__cplusplus", "201103L");
326     // C++03 [cpp.predefined]p1:
327     //   The name __cplusplus is defined to the value 199711L when compiling a
328     //   C++ translation unit.
329     else
330       Builder.defineMacro("__cplusplus", "199711L");
331   }
332 
333   if (LangOpts.ObjC1)
334     Builder.defineMacro("__OBJC__");
335 
336   // Not "standard" per se, but available even with the -undef flag.
337   if (LangOpts.AsmPreprocessor)
338     Builder.defineMacro("__ASSEMBLER__");
339 }
340 
341 static void InitializePredefinedMacros(const TargetInfo &TI,
342                                        const LangOptions &LangOpts,
343                                        const FrontendOptions &FEOpts,
344                                        MacroBuilder &Builder) {
345   // Compiler version introspection macros.
346   Builder.defineMacro("__llvm__");  // LLVM Backend
347   Builder.defineMacro("__clang__"); // Clang Frontend
348 #define TOSTR2(X) #X
349 #define TOSTR(X) TOSTR2(X)
350   Builder.defineMacro("__clang_major__", TOSTR(CLANG_VERSION_MAJOR));
351   Builder.defineMacro("__clang_minor__", TOSTR(CLANG_VERSION_MINOR));
352 #ifdef CLANG_VERSION_PATCHLEVEL
353   Builder.defineMacro("__clang_patchlevel__", TOSTR(CLANG_VERSION_PATCHLEVEL));
354 #else
355   Builder.defineMacro("__clang_patchlevel__", "0");
356 #endif
357   Builder.defineMacro("__clang_version__",
358                       "\"" CLANG_VERSION_STRING " "
359                       + getClangFullRepositoryVersion() + "\"");
360 #undef TOSTR
361 #undef TOSTR2
362   if (!LangOpts.MicrosoftMode) {
363     // Currently claim to be compatible with GCC 4.2.1-5621, but only if we're
364     // not compiling for MSVC compatibility
365     Builder.defineMacro("__GNUC_MINOR__", "2");
366     Builder.defineMacro("__GNUC_PATCHLEVEL__", "1");
367     Builder.defineMacro("__GNUC__", "4");
368     Builder.defineMacro("__GXX_ABI_VERSION", "1002");
369   }
370 
371   // Define macros for the C11 / C++11 memory orderings
372   Builder.defineMacro("__ATOMIC_RELAXED", "0");
373   Builder.defineMacro("__ATOMIC_CONSUME", "1");
374   Builder.defineMacro("__ATOMIC_ACQUIRE", "2");
375   Builder.defineMacro("__ATOMIC_RELEASE", "3");
376   Builder.defineMacro("__ATOMIC_ACQ_REL", "4");
377   Builder.defineMacro("__ATOMIC_SEQ_CST", "5");
378 
379   // Support for #pragma redefine_extname (Sun compatibility)
380   Builder.defineMacro("__PRAGMA_REDEFINE_EXTNAME", "1");
381 
382   // As sad as it is, enough software depends on the __VERSION__ for version
383   // checks that it is necessary to report 4.2.1 (the base GCC version we claim
384   // compatibility with) first.
385   Builder.defineMacro("__VERSION__", "\"4.2.1 Compatible " +
386                       Twine(getClangFullCPPVersion()) + "\"");
387 
388   // Initialize language-specific preprocessor defines.
389 
390   // Standard conforming mode?
391   if (!LangOpts.GNUMode)
392     Builder.defineMacro("__STRICT_ANSI__");
393 
394   if (LangOpts.CPlusPlus11)
395     Builder.defineMacro("__GXX_EXPERIMENTAL_CXX0X__");
396 
397   if (LangOpts.ObjC1) {
398     if (LangOpts.ObjCRuntime.isNonFragile()) {
399       Builder.defineMacro("__OBJC2__");
400 
401       if (LangOpts.ObjCExceptions)
402         Builder.defineMacro("OBJC_ZEROCOST_EXCEPTIONS");
403     }
404 
405     if (LangOpts.getGC() != LangOptions::NonGC)
406       Builder.defineMacro("__OBJC_GC__");
407 
408     if (LangOpts.ObjCRuntime.isNeXTFamily())
409       Builder.defineMacro("__NEXT_RUNTIME__");
410 
411     Builder.defineMacro("IBOutlet", "__attribute__((iboutlet))");
412     Builder.defineMacro("IBOutletCollection(ClassName)",
413                         "__attribute__((iboutletcollection(ClassName)))");
414     Builder.defineMacro("IBAction", "void)__attribute__((ibaction)");
415   }
416 
417   // darwin_constant_cfstrings controls this. This is also dependent
418   // on other things like the runtime I believe.  This is set even for C code.
419   if (!LangOpts.NoConstantCFStrings)
420       Builder.defineMacro("__CONSTANT_CFSTRINGS__");
421 
422   if (LangOpts.ObjC2)
423     Builder.defineMacro("OBJC_NEW_PROPERTIES");
424 
425   if (LangOpts.PascalStrings)
426     Builder.defineMacro("__PASCAL_STRINGS__");
427 
428   if (LangOpts.Blocks) {
429     Builder.defineMacro("__block", "__attribute__((__blocks__(byref)))");
430     Builder.defineMacro("__BLOCKS__");
431   }
432 
433   if (LangOpts.CXXExceptions)
434     Builder.defineMacro("__EXCEPTIONS");
435   if (LangOpts.RTTI)
436     Builder.defineMacro("__GXX_RTTI");
437   if (LangOpts.SjLjExceptions)
438     Builder.defineMacro("__USING_SJLJ_EXCEPTIONS__");
439 
440   if (LangOpts.Deprecated)
441     Builder.defineMacro("__DEPRECATED");
442 
443   if (LangOpts.CPlusPlus) {
444     Builder.defineMacro("__GNUG__", "4");
445     Builder.defineMacro("__GXX_WEAK__");
446     Builder.defineMacro("__private_extern__", "extern");
447   }
448 
449   if (LangOpts.MicrosoftExt) {
450     // Both __PRETTY_FUNCTION__ and __FUNCTION__ are GCC extensions, however
451     // VC++ appears to only like __FUNCTION__.
452     Builder.defineMacro("__PRETTY_FUNCTION__", "__FUNCTION__");
453     // Work around some issues with Visual C++ headers.
454     if (LangOpts.WChar) {
455       // wchar_t supported as a keyword.
456       Builder.defineMacro("_WCHAR_T_DEFINED");
457       Builder.defineMacro("_NATIVE_WCHAR_T_DEFINED");
458     }
459     if (LangOpts.CPlusPlus) {
460       // FIXME: Support Microsoft's __identifier extension in the lexer.
461       Builder.append("#define __identifier(x) x");
462       Builder.append("class type_info;");
463     }
464   }
465 
466   if (LangOpts.Optimize)
467     Builder.defineMacro("__OPTIMIZE__");
468   if (LangOpts.OptimizeSize)
469     Builder.defineMacro("__OPTIMIZE_SIZE__");
470 
471   if (LangOpts.FastMath)
472     Builder.defineMacro("__FAST_MATH__");
473 
474   // Initialize target-specific preprocessor defines.
475 
476   // __BYTE_ORDER__ was added in GCC 4.6. It's analogous
477   // to the macro __BYTE_ORDER (no trailing underscores)
478   // from glibc's <endian.h> header.
479   // We don't support the PDP-11 as a target, but include
480   // the define so it can still be compared against.
481   Builder.defineMacro("__ORDER_LITTLE_ENDIAN__", "1234");
482   Builder.defineMacro("__ORDER_BIG_ENDIAN__",    "4321");
483   Builder.defineMacro("__ORDER_PDP_ENDIAN__",    "3412");
484   if (TI.isBigEndian())
485     Builder.defineMacro("__BYTE_ORDER__", "__ORDER_BIG_ENDIAN__");
486   else
487     Builder.defineMacro("__BYTE_ORDER__", "__ORDER_LITTLE_ENDIAN__");
488 
489 
490   if (TI.getPointerWidth(0) == 64 && TI.getLongWidth() == 64
491       && TI.getIntWidth() == 32) {
492     Builder.defineMacro("_LP64");
493     Builder.defineMacro("__LP64__");
494   }
495 
496   // Define type sizing macros based on the target properties.
497   assert(TI.getCharWidth() == 8 && "Only support 8-bit char so far");
498   Builder.defineMacro("__CHAR_BIT__", "8");
499 
500   DefineTypeSize("__SCHAR_MAX__", TI.getCharWidth(), "", true, Builder);
501   DefineTypeSize("__SHRT_MAX__", TargetInfo::SignedShort, TI, Builder);
502   DefineTypeSize("__INT_MAX__", TargetInfo::SignedInt, TI, Builder);
503   DefineTypeSize("__LONG_MAX__", TargetInfo::SignedLong, TI, Builder);
504   DefineTypeSize("__LONG_LONG_MAX__", TargetInfo::SignedLongLong, TI, Builder);
505   DefineTypeSize("__WCHAR_MAX__", TI.getWCharType(), TI, Builder);
506   DefineTypeSize("__INTMAX_MAX__", TI.getIntMaxType(), TI, Builder);
507   DefineTypeSize("__SIZE_MAX__", TI.getSizeType(), TI, Builder);
508 
509   DefineTypeSizeof("__SIZEOF_DOUBLE__", TI.getDoubleWidth(), TI, Builder);
510   DefineTypeSizeof("__SIZEOF_FLOAT__", TI.getFloatWidth(), TI, Builder);
511   DefineTypeSizeof("__SIZEOF_INT__", TI.getIntWidth(), TI, Builder);
512   DefineTypeSizeof("__SIZEOF_LONG__", TI.getLongWidth(), TI, Builder);
513   DefineTypeSizeof("__SIZEOF_LONG_DOUBLE__",TI.getLongDoubleWidth(),TI,Builder);
514   DefineTypeSizeof("__SIZEOF_LONG_LONG__", TI.getLongLongWidth(), TI, Builder);
515   DefineTypeSizeof("__SIZEOF_POINTER__", TI.getPointerWidth(0), TI, Builder);
516   DefineTypeSizeof("__SIZEOF_SHORT__", TI.getShortWidth(), TI, Builder);
517   DefineTypeSizeof("__SIZEOF_PTRDIFF_T__",
518                    TI.getTypeWidth(TI.getPtrDiffType(0)), TI, Builder);
519   DefineTypeSizeof("__SIZEOF_SIZE_T__",
520                    TI.getTypeWidth(TI.getSizeType()), TI, Builder);
521   DefineTypeSizeof("__SIZEOF_WCHAR_T__",
522                    TI.getTypeWidth(TI.getWCharType()), TI, Builder);
523   DefineTypeSizeof("__SIZEOF_WINT_T__",
524                    TI.getTypeWidth(TI.getWIntType()), TI, Builder);
525   if (TI.hasInt128Type())
526     DefineTypeSizeof("__SIZEOF_INT128__", 128, TI, Builder);
527 
528   DefineType("__INTMAX_TYPE__", TI.getIntMaxType(), Builder);
529   DefineType("__UINTMAX_TYPE__", TI.getUIntMaxType(), Builder);
530   DefineTypeWidth("__INTMAX_WIDTH__",  TI.getIntMaxType(), TI, Builder);
531   DefineType("__PTRDIFF_TYPE__", TI.getPtrDiffType(0), Builder);
532   DefineTypeWidth("__PTRDIFF_WIDTH__", TI.getPtrDiffType(0), TI, Builder);
533   DefineType("__INTPTR_TYPE__", TI.getIntPtrType(), Builder);
534   DefineTypeWidth("__INTPTR_WIDTH__", TI.getIntPtrType(), TI, Builder);
535   DefineType("__SIZE_TYPE__", TI.getSizeType(), Builder);
536   DefineTypeWidth("__SIZE_WIDTH__", TI.getSizeType(), TI, Builder);
537   DefineType("__WCHAR_TYPE__", TI.getWCharType(), Builder);
538   DefineTypeWidth("__WCHAR_WIDTH__", TI.getWCharType(), TI, Builder);
539   DefineType("__WINT_TYPE__", TI.getWIntType(), Builder);
540   DefineTypeWidth("__WINT_WIDTH__", TI.getWIntType(), TI, Builder);
541   DefineTypeWidth("__SIG_ATOMIC_WIDTH__", TI.getSigAtomicType(), TI, Builder);
542   DefineType("__CHAR16_TYPE__", TI.getChar16Type(), Builder);
543   DefineType("__CHAR32_TYPE__", TI.getChar32Type(), Builder);
544 
545   DefineFloatMacros(Builder, "FLT", &TI.getFloatFormat(), "F");
546   DefineFloatMacros(Builder, "DBL", &TI.getDoubleFormat(), "");
547   DefineFloatMacros(Builder, "LDBL", &TI.getLongDoubleFormat(), "L");
548 
549   // Define a __POINTER_WIDTH__ macro for stdint.h.
550   Builder.defineMacro("__POINTER_WIDTH__",
551                       Twine((int)TI.getPointerWidth(0)));
552 
553   if (!LangOpts.CharIsSigned)
554     Builder.defineMacro("__CHAR_UNSIGNED__");
555 
556   if (!TargetInfo::isTypeSigned(TI.getWCharType()))
557     Builder.defineMacro("__WCHAR_UNSIGNED__");
558 
559   if (!TargetInfo::isTypeSigned(TI.getWIntType()))
560     Builder.defineMacro("__WINT_UNSIGNED__");
561 
562   // Define exact-width integer types for stdint.h
563   Builder.defineMacro("__INT" + Twine(TI.getCharWidth()) + "_TYPE__",
564                       "char");
565 
566   if (TI.getShortWidth() > TI.getCharWidth())
567     DefineExactWidthIntType(TargetInfo::SignedShort, TI, Builder);
568 
569   if (TI.getIntWidth() > TI.getShortWidth())
570     DefineExactWidthIntType(TargetInfo::SignedInt, TI, Builder);
571 
572   if (TI.getLongWidth() > TI.getIntWidth())
573     DefineExactWidthIntType(TargetInfo::SignedLong, TI, Builder);
574 
575   if (TI.getLongLongWidth() > TI.getLongWidth())
576     DefineExactWidthIntType(TargetInfo::SignedLongLong, TI, Builder);
577 
578   if (const char *Prefix = TI.getUserLabelPrefix())
579     Builder.defineMacro("__USER_LABEL_PREFIX__", Prefix);
580 
581   if (LangOpts.FastMath || LangOpts.FiniteMathOnly)
582     Builder.defineMacro("__FINITE_MATH_ONLY__", "1");
583   else
584     Builder.defineMacro("__FINITE_MATH_ONLY__", "0");
585 
586   if (LangOpts.GNUInline)
587     Builder.defineMacro("__GNUC_GNU_INLINE__");
588   else
589     Builder.defineMacro("__GNUC_STDC_INLINE__");
590 
591   // The value written by __atomic_test_and_set.
592   // FIXME: This is target-dependent.
593   Builder.defineMacro("__GCC_ATOMIC_TEST_AND_SET_TRUEVAL", "1");
594 
595   // Used by libstdc++ to implement ATOMIC_<foo>_LOCK_FREE.
596   unsigned InlineWidthBits = TI.getMaxAtomicInlineWidth();
597 #define DEFINE_LOCK_FREE_MACRO(TYPE, Type) \
598   Builder.defineMacro("__GCC_ATOMIC_" #TYPE "_LOCK_FREE", \
599                       getLockFreeValue(TI.get##Type##Width(), \
600                                        TI.get##Type##Align(), \
601                                        InlineWidthBits));
602   DEFINE_LOCK_FREE_MACRO(BOOL, Bool);
603   DEFINE_LOCK_FREE_MACRO(CHAR, Char);
604   DEFINE_LOCK_FREE_MACRO(CHAR16_T, Char16);
605   DEFINE_LOCK_FREE_MACRO(CHAR32_T, Char32);
606   DEFINE_LOCK_FREE_MACRO(WCHAR_T, WChar);
607   DEFINE_LOCK_FREE_MACRO(SHORT, Short);
608   DEFINE_LOCK_FREE_MACRO(INT, Int);
609   DEFINE_LOCK_FREE_MACRO(LONG, Long);
610   DEFINE_LOCK_FREE_MACRO(LLONG, LongLong);
611   Builder.defineMacro("__GCC_ATOMIC_POINTER_LOCK_FREE",
612                       getLockFreeValue(TI.getPointerWidth(0),
613                                        TI.getPointerAlign(0),
614                                        InlineWidthBits));
615 #undef DEFINE_LOCK_FREE_MACRO
616 
617   if (LangOpts.NoInlineDefine)
618     Builder.defineMacro("__NO_INLINE__");
619 
620   if (unsigned PICLevel = LangOpts.PICLevel) {
621     Builder.defineMacro("__PIC__", Twine(PICLevel));
622     Builder.defineMacro("__pic__", Twine(PICLevel));
623   }
624   if (unsigned PIELevel = LangOpts.PIELevel) {
625     Builder.defineMacro("__PIE__", Twine(PIELevel));
626     Builder.defineMacro("__pie__", Twine(PIELevel));
627   }
628 
629   // Macros to control C99 numerics and <float.h>
630   Builder.defineMacro("__FLT_EVAL_METHOD__", Twine(TI.getFloatEvalMethod()));
631   Builder.defineMacro("__FLT_RADIX__", "2");
632   int Dig = PickFP(&TI.getLongDoubleFormat(), -1/*FIXME*/, 17, 21, 33, 36);
633   Builder.defineMacro("__DECIMAL_DIG__", Twine(Dig));
634 
635   if (LangOpts.getStackProtector() == LangOptions::SSPOn)
636     Builder.defineMacro("__SSP__");
637   else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
638     Builder.defineMacro("__SSP_ALL__", "2");
639 
640   if (FEOpts.ProgramAction == frontend::RewriteObjC)
641     Builder.defineMacro("__weak", "__attribute__((objc_gc(weak)))");
642 
643   // Define a macro that exists only when using the static analyzer.
644   if (FEOpts.ProgramAction == frontend::RunAnalysis)
645     Builder.defineMacro("__clang_analyzer__");
646 
647   if (LangOpts.FastRelaxedMath)
648     Builder.defineMacro("__FAST_RELAXED_MATH__");
649 
650   if (LangOpts.ObjCAutoRefCount) {
651     Builder.defineMacro("__weak", "__attribute__((objc_ownership(weak)))");
652     Builder.defineMacro("__strong", "__attribute__((objc_ownership(strong)))");
653     Builder.defineMacro("__autoreleasing",
654                         "__attribute__((objc_ownership(autoreleasing)))");
655     Builder.defineMacro("__unsafe_unretained",
656                         "__attribute__((objc_ownership(none)))");
657   }
658 
659   // OpenMP definition
660   if (LangOpts.OpenMP) {
661     // OpenMP 2.2:
662     //   In implementations that support a preprocessor, the _OPENMP
663     //   macro name is defined to have the decimal value yyyymm where
664     //   yyyy and mm are the year and the month designations of the
665     //   version of the OpenMP API that the implementation support.
666     Builder.defineMacro("_OPENMP", "201107");
667   }
668 
669   // Get other target #defines.
670   TI.getTargetDefines(LangOpts, Builder);
671 }
672 
673 // Initialize the remapping of files to alternative contents, e.g.,
674 // those specified through other files.
675 static void InitializeFileRemapping(DiagnosticsEngine &Diags,
676                                     SourceManager &SourceMgr,
677                                     FileManager &FileMgr,
678                                     const PreprocessorOptions &InitOpts) {
679   // Remap files in the source manager (with buffers).
680   for (PreprocessorOptions::const_remapped_file_buffer_iterator
681          Remap = InitOpts.remapped_file_buffer_begin(),
682          RemapEnd = InitOpts.remapped_file_buffer_end();
683        Remap != RemapEnd;
684        ++Remap) {
685     // Create the file entry for the file that we're mapping from.
686     const FileEntry *FromFile = FileMgr.getVirtualFile(Remap->first,
687                                                 Remap->second->getBufferSize(),
688                                                        0);
689     if (!FromFile) {
690       Diags.Report(diag::err_fe_remap_missing_from_file)
691         << Remap->first;
692       if (!InitOpts.RetainRemappedFileBuffers)
693         delete Remap->second;
694       continue;
695     }
696 
697     // Override the contents of the "from" file with the contents of
698     // the "to" file.
699     SourceMgr.overrideFileContents(FromFile, Remap->second,
700                                    InitOpts.RetainRemappedFileBuffers);
701   }
702 
703   // Remap files in the source manager (with other files).
704   for (PreprocessorOptions::const_remapped_file_iterator
705          Remap = InitOpts.remapped_file_begin(),
706          RemapEnd = InitOpts.remapped_file_end();
707        Remap != RemapEnd;
708        ++Remap) {
709     // Find the file that we're mapping to.
710     const FileEntry *ToFile = FileMgr.getFile(Remap->second);
711     if (!ToFile) {
712       Diags.Report(diag::err_fe_remap_missing_to_file)
713       << Remap->first << Remap->second;
714       continue;
715     }
716 
717     // Create the file entry for the file that we're mapping from.
718     const FileEntry *FromFile = FileMgr.getVirtualFile(Remap->first,
719                                                        ToFile->getSize(), 0);
720     if (!FromFile) {
721       Diags.Report(diag::err_fe_remap_missing_from_file)
722       << Remap->first;
723       continue;
724     }
725 
726     // Override the contents of the "from" file with the contents of
727     // the "to" file.
728     SourceMgr.overrideFileContents(FromFile, ToFile);
729   }
730 
731   SourceMgr.setOverridenFilesKeepOriginalName(
732                                         InitOpts.RemappedFilesKeepOriginalName);
733 }
734 
735 /// InitializePreprocessor - Initialize the preprocessor getting it and the
736 /// environment ready to process a single file. This returns true on error.
737 ///
738 void clang::InitializePreprocessor(Preprocessor &PP,
739                                    const PreprocessorOptions &InitOpts,
740                                    const HeaderSearchOptions &HSOpts,
741                                    const FrontendOptions &FEOpts) {
742   const LangOptions &LangOpts = PP.getLangOpts();
743   std::string PredefineBuffer;
744   PredefineBuffer.reserve(4080);
745   llvm::raw_string_ostream Predefines(PredefineBuffer);
746   MacroBuilder Builder(Predefines);
747 
748   InitializeFileRemapping(PP.getDiagnostics(), PP.getSourceManager(),
749                           PP.getFileManager(), InitOpts);
750 
751   // Emit line markers for various builtin sections of the file.  We don't do
752   // this in asm preprocessor mode, because "# 4" is not a line marker directive
753   // in this mode.
754   if (!PP.getLangOpts().AsmPreprocessor)
755     Builder.append("# 1 \"<built-in>\" 3");
756 
757   // Install things like __POWERPC__, __GNUC__, etc into the macro table.
758   if (InitOpts.UsePredefines) {
759     InitializePredefinedMacros(PP.getTargetInfo(), LangOpts, FEOpts, Builder);
760 
761     // Install definitions to make Objective-C++ ARC work well with various
762     // C++ Standard Library implementations.
763     if (LangOpts.ObjC1 && LangOpts.CPlusPlus && LangOpts.ObjCAutoRefCount) {
764       switch (InitOpts.ObjCXXARCStandardLibrary) {
765       case ARCXX_nolib:
766         case ARCXX_libcxx:
767         break;
768 
769       case ARCXX_libstdcxx:
770         AddObjCXXARCLibstdcxxDefines(LangOpts, Builder);
771         break;
772       }
773     }
774   }
775 
776   // Even with predefines off, some macros are still predefined.
777   // These should all be defined in the preprocessor according to the
778   // current language configuration.
779   InitializeStandardPredefinedMacros(PP.getTargetInfo(), PP.getLangOpts(),
780                                      FEOpts, Builder);
781 
782   // Add on the predefines from the driver.  Wrap in a #line directive to report
783   // that they come from the command line.
784   if (!PP.getLangOpts().AsmPreprocessor)
785     Builder.append("# 1 \"<command line>\" 1");
786 
787   // Process #define's and #undef's in the order they are given.
788   for (unsigned i = 0, e = InitOpts.Macros.size(); i != e; ++i) {
789     if (InitOpts.Macros[i].second)  // isUndef
790       Builder.undefineMacro(InitOpts.Macros[i].first);
791     else
792       DefineBuiltinMacro(Builder, InitOpts.Macros[i].first,
793                          PP.getDiagnostics());
794   }
795 
796   // If -imacros are specified, include them now.  These are processed before
797   // any -include directives.
798   for (unsigned i = 0, e = InitOpts.MacroIncludes.size(); i != e; ++i)
799     AddImplicitIncludeMacros(Builder, InitOpts.MacroIncludes[i],
800                              PP.getFileManager());
801 
802   // Process -include-pch/-include-pth directives.
803   if (!InitOpts.ImplicitPCHInclude.empty())
804     AddImplicitIncludePCH(Builder, PP, InitOpts.ImplicitPCHInclude);
805   if (!InitOpts.ImplicitPTHInclude.empty())
806     AddImplicitIncludePTH(Builder, PP, InitOpts.ImplicitPTHInclude);
807 
808   // Process -include directives.
809   for (unsigned i = 0, e = InitOpts.Includes.size(); i != e; ++i) {
810     const std::string &Path = InitOpts.Includes[i];
811     AddImplicitInclude(Builder, Path, PP.getFileManager());
812   }
813 
814   // Exit the command line and go back to <built-in> (2 is LC_LEAVE).
815   if (!PP.getLangOpts().AsmPreprocessor)
816     Builder.append("# 1 \"<built-in>\" 2");
817 
818   // Instruct the preprocessor to skip the preamble.
819   PP.setSkipMainFilePreamble(InitOpts.PrecompiledPreambleBytes.first,
820                              InitOpts.PrecompiledPreambleBytes.second);
821 
822   // Copy PredefinedBuffer into the Preprocessor.
823   PP.setPredefines(Predefines.str());
824 
825   // Initialize the header search object.
826   ApplyHeaderSearchOptions(PP.getHeaderSearchInfo(), HSOpts,
827                            PP.getLangOpts(),
828                            PP.getTargetInfo().getTriple());
829 }
830