xref: /llvm-project/clang/lib/Frontend/InitPreprocessor.cpp (revision fa35df628a4ab331347dc448ccde573d6a7fa81d)
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/Basic/Version.h"
15 #include "clang/Frontend/Utils.h"
16 #include "clang/Basic/MacroBuilder.h"
17 #include "clang/Basic/TargetInfo.h"
18 #include "clang/Frontend/FrontendDiagnostic.h"
19 #include "clang/Frontend/FrontendOptions.h"
20 #include "clang/Frontend/PreprocessorOptions.h"
21 #include "clang/Lex/HeaderSearch.h"
22 #include "clang/Lex/Preprocessor.h"
23 #include "clang/Basic/FileManager.h"
24 #include "clang/Basic/SourceManager.h"
25 #include "llvm/ADT/APFloat.h"
26 #include "llvm/Support/FileSystem.h"
27 #include "llvm/Support/MemoryBuffer.h"
28 #include "llvm/Support/Path.h"
29 using namespace clang;
30 
31 // Append a #define line to Buf for Macro.  Macro should be of the form XXX,
32 // in which case we emit "#define XXX 1" or "XXX=Y z W" in which case we emit
33 // "#define XXX Y z W".  To get a #define with no value, use "XXX=".
34 static void DefineBuiltinMacro(MacroBuilder &Builder, StringRef Macro,
35                                DiagnosticsEngine &Diags) {
36   std::pair<StringRef, StringRef> MacroPair = Macro.split('=');
37   StringRef MacroName = MacroPair.first;
38   StringRef MacroBody = MacroPair.second;
39   if (MacroName.size() != Macro.size()) {
40     // Per GCC -D semantics, the macro ends at \n if it exists.
41     StringRef::size_type End = MacroBody.find_first_of("\n\r");
42     if (End != StringRef::npos)
43       Diags.Report(diag::warn_fe_macro_contains_embedded_newline)
44         << MacroName;
45     Builder.defineMacro(MacroName, MacroBody.substr(0, End));
46   } else {
47     // Push "macroname 1".
48     Builder.defineMacro(Macro);
49   }
50 }
51 
52 /// AddImplicitInclude - Add an implicit #include of the specified file to the
53 /// predefines buffer.
54 static void AddImplicitInclude(MacroBuilder &Builder, StringRef File,
55                                FileManager &FileMgr) {
56   Builder.append(Twine("#include \"") +
57                  HeaderSearch::NormalizeDashIncludePath(File, FileMgr) + "\"");
58 }
59 
60 static void AddImplicitIncludeMacros(MacroBuilder &Builder,
61                                      StringRef File,
62                                      FileManager &FileMgr) {
63   Builder.append(Twine("#__include_macros \"") +
64                  HeaderSearch::NormalizeDashIncludePath(File, FileMgr) + "\"");
65   // Marker token to stop the __include_macros fetch loop.
66   Builder.append("##"); // ##?
67 }
68 
69 /// AddImplicitIncludePTH - Add an implicit #include using the original file
70 ///  used to generate a PTH cache.
71 static void AddImplicitIncludePTH(MacroBuilder &Builder, Preprocessor &PP,
72                                   StringRef ImplicitIncludePTH) {
73   PTHManager *P = PP.getPTHManager();
74   // Null check 'P' in the corner case where it couldn't be created.
75   const char *OriginalFile = P ? P->getOriginalSourceFile() : 0;
76 
77   if (!OriginalFile) {
78     PP.getDiagnostics().Report(diag::err_fe_pth_file_has_no_source_header)
79       << ImplicitIncludePTH;
80     return;
81   }
82 
83   AddImplicitInclude(Builder, OriginalFile, PP.getFileManager());
84 }
85 
86 /// PickFP - This is used to pick a value based on the FP semantics of the
87 /// specified FP model.
88 template <typename T>
89 static T PickFP(const llvm::fltSemantics *Sem, T IEEESingleVal,
90                 T IEEEDoubleVal, T X87DoubleExtendedVal, T PPCDoubleDoubleVal,
91                 T IEEEQuadVal) {
92   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEsingle)
93     return IEEESingleVal;
94   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEdouble)
95     return IEEEDoubleVal;
96   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::x87DoubleExtended)
97     return X87DoubleExtendedVal;
98   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::PPCDoubleDouble)
99     return PPCDoubleDoubleVal;
100   assert(Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEquad);
101   return IEEEQuadVal;
102 }
103 
104 static void DefineFloatMacros(MacroBuilder &Builder, StringRef Prefix,
105                               const llvm::fltSemantics *Sem) {
106   const char *DenormMin, *Epsilon, *Max, *Min;
107   DenormMin = PickFP(Sem, "1.40129846e-45F", "4.9406564584124654e-324",
108                      "3.64519953188247460253e-4951L",
109                      "4.94065645841246544176568792868221e-324L",
110                      "6.47517511943802511092443895822764655e-4966L");
111   int Digits = PickFP(Sem, 6, 15, 18, 31, 33);
112   Epsilon = PickFP(Sem, "1.19209290e-7F", "2.2204460492503131e-16",
113                    "1.08420217248550443401e-19L",
114                    "4.94065645841246544176568792868221e-324L",
115                    "1.92592994438723585305597794258492732e-34L");
116   int MantissaDigits = PickFP(Sem, 24, 53, 64, 106, 113);
117   int Min10Exp = PickFP(Sem, -37, -307, -4931, -291, -4931);
118   int Max10Exp = PickFP(Sem, 38, 308, 4932, 308, 4932);
119   int MinExp = PickFP(Sem, -125, -1021, -16381, -968, -16381);
120   int MaxExp = PickFP(Sem, 128, 1024, 16384, 1024, 16384);
121   Min = PickFP(Sem, "1.17549435e-38F", "2.2250738585072014e-308",
122                "3.36210314311209350626e-4932L",
123                "2.00416836000897277799610805135016e-292L",
124                "3.36210314311209350626267781732175260e-4932L");
125   Max = PickFP(Sem, "3.40282347e+38F", "1.7976931348623157e+308",
126                "1.18973149535723176502e+4932L",
127                "1.79769313486231580793728971405301e+308L",
128                "1.18973149535723176508575932662800702e+4932L");
129 
130   llvm::SmallString<32> DefPrefix;
131   DefPrefix = "__";
132   DefPrefix += Prefix;
133   DefPrefix += "_";
134 
135   Builder.defineMacro(DefPrefix + "DENORM_MIN__", DenormMin);
136   Builder.defineMacro(DefPrefix + "HAS_DENORM__");
137   Builder.defineMacro(DefPrefix + "DIG__", Twine(Digits));
138   Builder.defineMacro(DefPrefix + "EPSILON__", Twine(Epsilon));
139   Builder.defineMacro(DefPrefix + "HAS_INFINITY__");
140   Builder.defineMacro(DefPrefix + "HAS_QUIET_NAN__");
141   Builder.defineMacro(DefPrefix + "MANT_DIG__", Twine(MantissaDigits));
142 
143   Builder.defineMacro(DefPrefix + "MAX_10_EXP__", Twine(Max10Exp));
144   Builder.defineMacro(DefPrefix + "MAX_EXP__", Twine(MaxExp));
145   Builder.defineMacro(DefPrefix + "MAX__", Twine(Max));
146 
147   Builder.defineMacro(DefPrefix + "MIN_10_EXP__","("+Twine(Min10Exp)+")");
148   Builder.defineMacro(DefPrefix + "MIN_EXP__", "("+Twine(MinExp)+")");
149   Builder.defineMacro(DefPrefix + "MIN__", Twine(Min));
150 }
151 
152 
153 /// DefineTypeSize - Emit a macro to the predefines buffer that declares a macro
154 /// named MacroName with the max value for a type with width 'TypeWidth' a
155 /// signedness of 'isSigned' and with a value suffix of 'ValSuffix' (e.g. LL).
156 static void DefineTypeSize(StringRef MacroName, unsigned TypeWidth,
157                            StringRef ValSuffix, bool isSigned,
158                            MacroBuilder &Builder) {
159   llvm::APInt MaxVal = isSigned ? llvm::APInt::getSignedMaxValue(TypeWidth)
160                                 : llvm::APInt::getMaxValue(TypeWidth);
161   Builder.defineMacro(MacroName, MaxVal.toString(10, isSigned) + ValSuffix);
162 }
163 
164 /// DefineTypeSize - An overloaded helper that uses TargetInfo to determine
165 /// the width, suffix, and signedness of the given type
166 static void DefineTypeSize(StringRef MacroName, TargetInfo::IntType Ty,
167                            const TargetInfo &TI, MacroBuilder &Builder) {
168   DefineTypeSize(MacroName, TI.getTypeWidth(Ty), TI.getTypeConstantSuffix(Ty),
169                  TI.isTypeSigned(Ty), Builder);
170 }
171 
172 static void DefineType(const Twine &MacroName, TargetInfo::IntType Ty,
173                        MacroBuilder &Builder) {
174   Builder.defineMacro(MacroName, TargetInfo::getTypeName(Ty));
175 }
176 
177 static void DefineTypeWidth(StringRef MacroName, TargetInfo::IntType Ty,
178                             const TargetInfo &TI, MacroBuilder &Builder) {
179   Builder.defineMacro(MacroName, Twine(TI.getTypeWidth(Ty)));
180 }
181 
182 static void DefineTypeSizeof(StringRef MacroName, unsigned BitWidth,
183                              const TargetInfo &TI, MacroBuilder &Builder) {
184   Builder.defineMacro(MacroName,
185                       Twine(BitWidth / TI.getCharWidth()));
186 }
187 
188 static void DefineExactWidthIntType(TargetInfo::IntType Ty,
189                                const TargetInfo &TI, MacroBuilder &Builder) {
190   int TypeWidth = TI.getTypeWidth(Ty);
191 
192   // Use the target specified int64 type, when appropriate, so that [u]int64_t
193   // ends up being defined in terms of the correct type.
194   if (TypeWidth == 64)
195     Ty = TI.getInt64Type();
196 
197   DefineType("__INT" + Twine(TypeWidth) + "_TYPE__", Ty, Builder);
198 
199   StringRef ConstSuffix(TargetInfo::getTypeConstantSuffix(Ty));
200   if (!ConstSuffix.empty())
201     Builder.defineMacro("__INT" + Twine(TypeWidth) + "_C_SUFFIX__",
202                         ConstSuffix);
203 }
204 
205 /// \brief Add definitions required for a smooth interaction between
206 /// Objective-C++ automated reference counting and libstdc++ (4.2).
207 static void AddObjCXXARCLibstdcxxDefines(const LangOptions &LangOpts,
208                                          MacroBuilder &Builder) {
209   Builder.defineMacro("_GLIBCXX_PREDEFINED_OBJC_ARC_IS_SCALAR");
210 
211   std::string Result;
212   {
213     // Provide specializations for the __is_scalar type trait so that
214     // lifetime-qualified objects are not considered "scalar" types, which
215     // libstdc++ uses as an indicator of the presence of trivial copy, assign,
216     // default-construct, and destruct semantics (none of which hold for
217     // lifetime-qualified objects in ARC).
218     llvm::raw_string_ostream Out(Result);
219 
220     Out << "namespace std {\n"
221         << "\n"
222         << "struct __true_type;\n"
223         << "struct __false_type;\n"
224         << "\n";
225 
226     Out << "template<typename _Tp> struct __is_scalar;\n"
227         << "\n";
228 
229     Out << "template<typename _Tp>\n"
230         << "struct __is_scalar<__attribute__((objc_ownership(strong))) _Tp> {\n"
231         << "  enum { __value = 0 };\n"
232         << "  typedef __false_type __type;\n"
233         << "};\n"
234         << "\n";
235 
236     if (LangOpts.ObjCRuntimeHasWeak) {
237       Out << "template<typename _Tp>\n"
238           << "struct __is_scalar<__attribute__((objc_ownership(weak))) _Tp> {\n"
239           << "  enum { __value = 0 };\n"
240           << "  typedef __false_type __type;\n"
241           << "};\n"
242           << "\n";
243     }
244 
245     Out << "template<typename _Tp>\n"
246         << "struct __is_scalar<__attribute__((objc_ownership(autoreleasing)))"
247         << " _Tp> {\n"
248         << "  enum { __value = 0 };\n"
249         << "  typedef __false_type __type;\n"
250         << "};\n"
251         << "\n";
252 
253     Out << "}\n";
254   }
255   Builder.append(Result);
256 }
257 
258 static void InitializeStandardPredefinedMacros(const TargetInfo &TI,
259                                                const LangOptions &LangOpts,
260                                                const FrontendOptions &FEOpts,
261                                                MacroBuilder &Builder) {
262   if (!LangOpts.MicrosoftMode && !LangOpts.TraditionalCPP)
263     Builder.defineMacro("__STDC__");
264   if (LangOpts.Freestanding)
265     Builder.defineMacro("__STDC_HOSTED__", "0");
266   else
267     Builder.defineMacro("__STDC_HOSTED__");
268 
269   if (!LangOpts.CPlusPlus) {
270     if (LangOpts.C11)
271       Builder.defineMacro("__STDC_VERSION__", "201112L");
272     else if (LangOpts.C99)
273       Builder.defineMacro("__STDC_VERSION__", "199901L");
274     else if (!LangOpts.GNUMode && LangOpts.Digraphs)
275       Builder.defineMacro("__STDC_VERSION__", "199409L");
276   } else {
277     if (LangOpts.GNUMode)
278       Builder.defineMacro("__cplusplus");
279     else {
280       // C++0x [cpp.predefined]p1:
281       //   The name_ _cplusplus is defined to the value 201103L when compiling a
282       //   C++ translation unit.
283       if (LangOpts.CPlusPlus0x)
284         Builder.defineMacro("__cplusplus", "201103L");
285       // C++03 [cpp.predefined]p1:
286       //   The name_ _cplusplus is defined to the value 199711L when compiling a
287       //   C++ translation unit.
288       else
289         Builder.defineMacro("__cplusplus", "199711L");
290     }
291   }
292 
293   if (LangOpts.ObjC1)
294     Builder.defineMacro("__OBJC__");
295 
296   // Not "standard" per se, but available even with the -undef flag.
297   if (LangOpts.AsmPreprocessor)
298     Builder.defineMacro("__ASSEMBLER__");
299 }
300 
301 static void InitializePredefinedMacros(const TargetInfo &TI,
302                                        const LangOptions &LangOpts,
303                                        const FrontendOptions &FEOpts,
304                                        MacroBuilder &Builder) {
305   // Compiler version introspection macros.
306   Builder.defineMacro("__llvm__");  // LLVM Backend
307   Builder.defineMacro("__clang__"); // Clang Frontend
308 #define TOSTR2(X) #X
309 #define TOSTR(X) TOSTR2(X)
310   Builder.defineMacro("__clang_major__", TOSTR(CLANG_VERSION_MAJOR));
311   Builder.defineMacro("__clang_minor__", TOSTR(CLANG_VERSION_MINOR));
312 #ifdef CLANG_VERSION_PATCHLEVEL
313   Builder.defineMacro("__clang_patchlevel__", TOSTR(CLANG_VERSION_PATCHLEVEL));
314 #else
315   Builder.defineMacro("__clang_patchlevel__", "0");
316 #endif
317   Builder.defineMacro("__clang_version__",
318                       "\"" CLANG_VERSION_STRING " ("
319                       + getClangFullRepositoryVersion() + ")\"");
320 #undef TOSTR
321 #undef TOSTR2
322   // Currently claim to be compatible with GCC 4.2.1-5621.
323   Builder.defineMacro("__GNUC_MINOR__", "2");
324   Builder.defineMacro("__GNUC_PATCHLEVEL__", "1");
325   Builder.defineMacro("__GNUC__", "4");
326   Builder.defineMacro("__GXX_ABI_VERSION", "1002");
327 
328   // Define macros for the C11 / C++11 memory orderings
329   Builder.defineMacro("__ATOMIC_RELAXED", "0");
330   Builder.defineMacro("__ATOMIC_CONSUME", "1");
331   Builder.defineMacro("__ATOMIC_ACQUIRE", "2");
332   Builder.defineMacro("__ATOMIC_RELEASE", "3");
333   Builder.defineMacro("__ATOMIC_ACQ_REL", "4");
334   Builder.defineMacro("__ATOMIC_SEQ_CST", "5");
335 
336   // As sad as it is, enough software depends on the __VERSION__ for version
337   // checks that it is necessary to report 4.2.1 (the base GCC version we claim
338   // compatibility with) first.
339   Builder.defineMacro("__VERSION__", "\"4.2.1 Compatible " +
340                       Twine(getClangFullCPPVersion()) + "\"");
341 
342   // Initialize language-specific preprocessor defines.
343 
344   // Standard conforming mode?
345   if (!LangOpts.GNUMode)
346     Builder.defineMacro("__STRICT_ANSI__");
347 
348   if (LangOpts.CPlusPlus0x)
349     Builder.defineMacro("__GXX_EXPERIMENTAL_CXX0X__");
350 
351   if (LangOpts.ObjC1) {
352     if (LangOpts.ObjCNonFragileABI) {
353       Builder.defineMacro("__OBJC2__");
354 
355       if (LangOpts.ObjCExceptions)
356         Builder.defineMacro("OBJC_ZEROCOST_EXCEPTIONS");
357     }
358 
359     if (LangOpts.getGC() != LangOptions::NonGC)
360       Builder.defineMacro("__OBJC_GC__");
361 
362     if (LangOpts.NeXTRuntime)
363       Builder.defineMacro("__NEXT_RUNTIME__");
364   }
365 
366   // darwin_constant_cfstrings controls this. This is also dependent
367   // on other things like the runtime I believe.  This is set even for C code.
368   if (!LangOpts.NoConstantCFStrings)
369       Builder.defineMacro("__CONSTANT_CFSTRINGS__");
370 
371   if (LangOpts.ObjC2)
372     Builder.defineMacro("OBJC_NEW_PROPERTIES");
373 
374   if (LangOpts.PascalStrings)
375     Builder.defineMacro("__PASCAL_STRINGS__");
376 
377   if (LangOpts.Blocks) {
378     Builder.defineMacro("__block", "__attribute__((__blocks__(byref)))");
379     Builder.defineMacro("__BLOCKS__");
380   }
381 
382   if (LangOpts.CXXExceptions)
383     Builder.defineMacro("__EXCEPTIONS");
384   if (LangOpts.RTTI)
385     Builder.defineMacro("__GXX_RTTI");
386   if (LangOpts.SjLjExceptions)
387     Builder.defineMacro("__USING_SJLJ_EXCEPTIONS__");
388 
389   if (LangOpts.Deprecated)
390     Builder.defineMacro("__DEPRECATED");
391 
392   if (LangOpts.CPlusPlus) {
393     Builder.defineMacro("__GNUG__", "4");
394     Builder.defineMacro("__GXX_WEAK__");
395     Builder.defineMacro("__private_extern__", "extern");
396   }
397 
398   if (LangOpts.MicrosoftExt) {
399     // Both __PRETTY_FUNCTION__ and __FUNCTION__ are GCC extensions, however
400     // VC++ appears to only like __FUNCTION__.
401     Builder.defineMacro("__PRETTY_FUNCTION__", "__FUNCTION__");
402     // Work around some issues with Visual C++ headerws.
403     if (LangOpts.CPlusPlus) {
404       // Since we define wchar_t in C++ mode.
405       Builder.defineMacro("_WCHAR_T_DEFINED");
406       Builder.defineMacro("_NATIVE_WCHAR_T_DEFINED");
407       // FIXME: Support Microsoft's __identifier extension in the lexer.
408       Builder.append("#define __identifier(x) x");
409       Builder.append("class type_info;");
410     }
411 
412     if (LangOpts.CPlusPlus0x) {
413       Builder.defineMacro("_HAS_CHAR16_T_LANGUAGE_SUPPORT", "1");
414     }
415   }
416 
417   if (LangOpts.Optimize)
418     Builder.defineMacro("__OPTIMIZE__");
419   if (LangOpts.OptimizeSize)
420     Builder.defineMacro("__OPTIMIZE_SIZE__");
421 
422   if (LangOpts.FastMath)
423     Builder.defineMacro("__FAST_MATH__");
424 
425   // Initialize target-specific preprocessor defines.
426 
427   // Define type sizing macros based on the target properties.
428   assert(TI.getCharWidth() == 8 && "Only support 8-bit char so far");
429   Builder.defineMacro("__CHAR_BIT__", "8");
430 
431   DefineTypeSize("__SCHAR_MAX__", TI.getCharWidth(), "", true, Builder);
432   DefineTypeSize("__SHRT_MAX__", TargetInfo::SignedShort, TI, Builder);
433   DefineTypeSize("__INT_MAX__", TargetInfo::SignedInt, TI, Builder);
434   DefineTypeSize("__LONG_MAX__", TargetInfo::SignedLong, TI, Builder);
435   DefineTypeSize("__LONG_LONG_MAX__", TargetInfo::SignedLongLong, TI, Builder);
436   DefineTypeSize("__WCHAR_MAX__", TI.getWCharType(), TI, Builder);
437   DefineTypeSize("__INTMAX_MAX__", TI.getIntMaxType(), TI, Builder);
438 
439   DefineTypeSizeof("__SIZEOF_DOUBLE__", TI.getDoubleWidth(), TI, Builder);
440   DefineTypeSizeof("__SIZEOF_FLOAT__", TI.getFloatWidth(), TI, Builder);
441   DefineTypeSizeof("__SIZEOF_INT__", TI.getIntWidth(), TI, Builder);
442   DefineTypeSizeof("__SIZEOF_LONG__", TI.getLongWidth(), TI, Builder);
443   DefineTypeSizeof("__SIZEOF_LONG_DOUBLE__",TI.getLongDoubleWidth(),TI,Builder);
444   DefineTypeSizeof("__SIZEOF_LONG_LONG__", TI.getLongLongWidth(), TI, Builder);
445   DefineTypeSizeof("__SIZEOF_POINTER__", TI.getPointerWidth(0), TI, Builder);
446   DefineTypeSizeof("__SIZEOF_SHORT__", TI.getShortWidth(), TI, Builder);
447   DefineTypeSizeof("__SIZEOF_PTRDIFF_T__",
448                    TI.getTypeWidth(TI.getPtrDiffType(0)), TI, Builder);
449   DefineTypeSizeof("__SIZEOF_SIZE_T__",
450                    TI.getTypeWidth(TI.getSizeType()), TI, Builder);
451   DefineTypeSizeof("__SIZEOF_WCHAR_T__",
452                    TI.getTypeWidth(TI.getWCharType()), TI, Builder);
453   DefineTypeSizeof("__SIZEOF_WINT_T__",
454                    TI.getTypeWidth(TI.getWIntType()), TI, Builder);
455 
456   DefineType("__INTMAX_TYPE__", TI.getIntMaxType(), Builder);
457   DefineType("__UINTMAX_TYPE__", TI.getUIntMaxType(), Builder);
458   DefineTypeWidth("__INTMAX_WIDTH__",  TI.getIntMaxType(), TI, Builder);
459   DefineType("__PTRDIFF_TYPE__", TI.getPtrDiffType(0), Builder);
460   DefineTypeWidth("__PTRDIFF_WIDTH__", TI.getPtrDiffType(0), TI, Builder);
461   DefineType("__INTPTR_TYPE__", TI.getIntPtrType(), Builder);
462   DefineTypeWidth("__INTPTR_WIDTH__", TI.getIntPtrType(), TI, Builder);
463   DefineType("__SIZE_TYPE__", TI.getSizeType(), Builder);
464   DefineTypeWidth("__SIZE_WIDTH__", TI.getSizeType(), TI, Builder);
465   DefineType("__WCHAR_TYPE__", TI.getWCharType(), Builder);
466   DefineTypeWidth("__WCHAR_WIDTH__", TI.getWCharType(), TI, Builder);
467   DefineType("__WINT_TYPE__", TI.getWIntType(), Builder);
468   DefineTypeWidth("__WINT_WIDTH__", TI.getWIntType(), TI, Builder);
469   DefineTypeWidth("__SIG_ATOMIC_WIDTH__", TI.getSigAtomicType(), TI, Builder);
470   DefineType("__CHAR16_TYPE__", TI.getChar16Type(), Builder);
471   DefineType("__CHAR32_TYPE__", TI.getChar32Type(), Builder);
472 
473   DefineFloatMacros(Builder, "FLT", &TI.getFloatFormat());
474   DefineFloatMacros(Builder, "DBL", &TI.getDoubleFormat());
475   DefineFloatMacros(Builder, "LDBL", &TI.getLongDoubleFormat());
476 
477   // Define a __POINTER_WIDTH__ macro for stdint.h.
478   Builder.defineMacro("__POINTER_WIDTH__",
479                       Twine((int)TI.getPointerWidth(0)));
480 
481   if (!LangOpts.CharIsSigned)
482     Builder.defineMacro("__CHAR_UNSIGNED__");
483 
484   if (!TargetInfo::isTypeSigned(TI.getWIntType()))
485     Builder.defineMacro("__WINT_UNSIGNED__");
486 
487   // Define exact-width integer types for stdint.h
488   Builder.defineMacro("__INT" + Twine(TI.getCharWidth()) + "_TYPE__",
489                       "char");
490 
491   if (TI.getShortWidth() > TI.getCharWidth())
492     DefineExactWidthIntType(TargetInfo::SignedShort, TI, Builder);
493 
494   if (TI.getIntWidth() > TI.getShortWidth())
495     DefineExactWidthIntType(TargetInfo::SignedInt, TI, Builder);
496 
497   if (TI.getLongWidth() > TI.getIntWidth())
498     DefineExactWidthIntType(TargetInfo::SignedLong, TI, Builder);
499 
500   if (TI.getLongLongWidth() > TI.getLongWidth())
501     DefineExactWidthIntType(TargetInfo::SignedLongLong, TI, Builder);
502 
503   // Add __builtin_va_list typedef.
504   Builder.append(TI.getVAListDeclaration());
505 
506   if (const char *Prefix = TI.getUserLabelPrefix())
507     Builder.defineMacro("__USER_LABEL_PREFIX__", Prefix);
508 
509   // Build configuration options.  FIXME: these should be controlled by
510   // command line options or something.
511   Builder.defineMacro("__FINITE_MATH_ONLY__", "0");
512 
513   if (LangOpts.GNUInline)
514     Builder.defineMacro("__GNUC_GNU_INLINE__");
515   else
516     Builder.defineMacro("__GNUC_STDC_INLINE__");
517 
518   if (LangOpts.NoInline)
519     Builder.defineMacro("__NO_INLINE__");
520 
521   if (unsigned PICLevel = LangOpts.PICLevel) {
522     Builder.defineMacro("__PIC__", Twine(PICLevel));
523     Builder.defineMacro("__pic__", Twine(PICLevel));
524   }
525 
526   // Macros to control C99 numerics and <float.h>
527   Builder.defineMacro("__FLT_EVAL_METHOD__", Twine(TI.getFloatEvalMethod()));
528   Builder.defineMacro("__FLT_RADIX__", "2");
529   int Dig = PickFP(&TI.getLongDoubleFormat(), -1/*FIXME*/, 17, 21, 33, 36);
530   Builder.defineMacro("__DECIMAL_DIG__", Twine(Dig));
531 
532   if (LangOpts.getStackProtector() == LangOptions::SSPOn)
533     Builder.defineMacro("__SSP__");
534   else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
535     Builder.defineMacro("__SSP_ALL__", "2");
536 
537   if (FEOpts.ProgramAction == frontend::RewriteObjC)
538     Builder.defineMacro("__weak", "__attribute__((objc_gc(weak)))");
539 
540   // Define a macro that exists only when using the static analyzer.
541   if (FEOpts.ProgramAction == frontend::RunAnalysis)
542     Builder.defineMacro("__clang_analyzer__");
543 
544   if (LangOpts.FastRelaxedMath)
545     Builder.defineMacro("__FAST_RELAXED_MATH__");
546 
547   if (LangOpts.ObjCAutoRefCount) {
548     Builder.defineMacro("__weak", "__attribute__((objc_ownership(weak)))");
549     Builder.defineMacro("__strong", "__attribute__((objc_ownership(strong)))");
550     Builder.defineMacro("__autoreleasing",
551                         "__attribute__((objc_ownership(autoreleasing)))");
552     Builder.defineMacro("__unsafe_unretained",
553                         "__attribute__((objc_ownership(none)))");
554   }
555 
556   // Get other target #defines.
557   TI.getTargetDefines(LangOpts, Builder);
558 }
559 
560 // Initialize the remapping of files to alternative contents, e.g.,
561 // those specified through other files.
562 static void InitializeFileRemapping(DiagnosticsEngine &Diags,
563                                     SourceManager &SourceMgr,
564                                     FileManager &FileMgr,
565                                     const PreprocessorOptions &InitOpts) {
566   // Remap files in the source manager (with buffers).
567   for (PreprocessorOptions::const_remapped_file_buffer_iterator
568          Remap = InitOpts.remapped_file_buffer_begin(),
569          RemapEnd = InitOpts.remapped_file_buffer_end();
570        Remap != RemapEnd;
571        ++Remap) {
572     // Create the file entry for the file that we're mapping from.
573     const FileEntry *FromFile = FileMgr.getVirtualFile(Remap->first,
574                                                 Remap->second->getBufferSize(),
575                                                        0);
576     if (!FromFile) {
577       Diags.Report(diag::err_fe_remap_missing_from_file)
578         << Remap->first;
579       if (!InitOpts.RetainRemappedFileBuffers)
580         delete Remap->second;
581       continue;
582     }
583 
584     // Override the contents of the "from" file with the contents of
585     // the "to" file.
586     SourceMgr.overrideFileContents(FromFile, Remap->second,
587                                    InitOpts.RetainRemappedFileBuffers);
588   }
589 
590   // Remap files in the source manager (with other files).
591   for (PreprocessorOptions::const_remapped_file_iterator
592          Remap = InitOpts.remapped_file_begin(),
593          RemapEnd = InitOpts.remapped_file_end();
594        Remap != RemapEnd;
595        ++Remap) {
596     // Find the file that we're mapping to.
597     const FileEntry *ToFile = FileMgr.getFile(Remap->second);
598     if (!ToFile) {
599       Diags.Report(diag::err_fe_remap_missing_to_file)
600       << Remap->first << Remap->second;
601       continue;
602     }
603 
604     // Create the file entry for the file that we're mapping from.
605     const FileEntry *FromFile = FileMgr.getVirtualFile(Remap->first,
606                                                        ToFile->getSize(), 0);
607     if (!FromFile) {
608       Diags.Report(diag::err_fe_remap_missing_from_file)
609       << Remap->first;
610       continue;
611     }
612 
613     // Override the contents of the "from" file with the contents of
614     // the "to" file.
615     SourceMgr.overrideFileContents(FromFile, ToFile);
616   }
617 
618   SourceMgr.setOverridenFilesKeepOriginalName(
619                                         InitOpts.RemappedFilesKeepOriginalName);
620 }
621 
622 /// InitializePreprocessor - Initialize the preprocessor getting it and the
623 /// environment ready to process a single file. This returns true on error.
624 ///
625 void clang::InitializePreprocessor(Preprocessor &PP,
626                                    const PreprocessorOptions &InitOpts,
627                                    const HeaderSearchOptions &HSOpts,
628                                    const FrontendOptions &FEOpts) {
629   const LangOptions &LangOpts = PP.getLangOptions();
630   std::string PredefineBuffer;
631   PredefineBuffer.reserve(4080);
632   llvm::raw_string_ostream Predefines(PredefineBuffer);
633   MacroBuilder Builder(Predefines);
634 
635   InitializeFileRemapping(PP.getDiagnostics(), PP.getSourceManager(),
636                           PP.getFileManager(), InitOpts);
637 
638   // Emit line markers for various builtin sections of the file.  We don't do
639   // this in asm preprocessor mode, because "# 4" is not a line marker directive
640   // in this mode.
641   if (!PP.getLangOptions().AsmPreprocessor)
642     Builder.append("# 1 \"<built-in>\" 3");
643 
644   // Install things like __POWERPC__, __GNUC__, etc into the macro table.
645   if (InitOpts.UsePredefines) {
646     InitializePredefinedMacros(PP.getTargetInfo(), LangOpts, FEOpts, Builder);
647 
648     // Install definitions to make Objective-C++ ARC work well with various
649     // C++ Standard Library implementations.
650     if (LangOpts.ObjC1 && LangOpts.CPlusPlus && LangOpts.ObjCAutoRefCount) {
651       switch (InitOpts.ObjCXXARCStandardLibrary) {
652       case ARCXX_nolib:
653         case ARCXX_libcxx:
654         break;
655 
656       case ARCXX_libstdcxx:
657         AddObjCXXARCLibstdcxxDefines(LangOpts, Builder);
658         break;
659       }
660     }
661   }
662 
663   // Even with predefines off, some macros are still predefined.
664   // These should all be defined in the preprocessor according to the
665   // current language configuration.
666   InitializeStandardPredefinedMacros(PP.getTargetInfo(), PP.getLangOptions(),
667                                      FEOpts, Builder);
668 
669   // Add on the predefines from the driver.  Wrap in a #line directive to report
670   // that they come from the command line.
671   if (!PP.getLangOptions().AsmPreprocessor)
672     Builder.append("# 1 \"<command line>\" 1");
673 
674   // Process #define's and #undef's in the order they are given.
675   for (unsigned i = 0, e = InitOpts.Macros.size(); i != e; ++i) {
676     if (InitOpts.Macros[i].second)  // isUndef
677       Builder.undefineMacro(InitOpts.Macros[i].first);
678     else
679       DefineBuiltinMacro(Builder, InitOpts.Macros[i].first,
680                          PP.getDiagnostics());
681   }
682 
683   // If -imacros are specified, include them now.  These are processed before
684   // any -include directives.
685   for (unsigned i = 0, e = InitOpts.MacroIncludes.size(); i != e; ++i)
686     AddImplicitIncludeMacros(Builder, InitOpts.MacroIncludes[i],
687                              PP.getFileManager());
688 
689   // Process -include directives.
690   for (unsigned i = 0, e = InitOpts.Includes.size(); i != e; ++i) {
691     const std::string &Path = InitOpts.Includes[i];
692     if (Path == InitOpts.ImplicitPTHInclude)
693       AddImplicitIncludePTH(Builder, PP, Path);
694     else
695       AddImplicitInclude(Builder, Path, PP.getFileManager());
696   }
697 
698   // Exit the command line and go back to <built-in> (2 is LC_LEAVE).
699   if (!PP.getLangOptions().AsmPreprocessor)
700     Builder.append("# 1 \"<built-in>\" 2");
701 
702   // Instruct the preprocessor to skip the preamble.
703   PP.setSkipMainFilePreamble(InitOpts.PrecompiledPreambleBytes.first,
704                              InitOpts.PrecompiledPreambleBytes.second);
705 
706   // Copy PredefinedBuffer into the Preprocessor.
707   PP.setPredefines(Predefines.str());
708 
709   // Initialize the header search object.
710   ApplyHeaderSearchOptions(PP.getHeaderSearchInfo(), HSOpts,
711                            PP.getLangOptions(),
712                            PP.getTargetInfo().getTriple());
713 }
714