xref: /llvm-project/clang/lib/Frontend/InitPreprocessor.cpp (revision 2875e2448c147d8a2335882819acdd4c8eb97ea6)
1 //===--- InitPreprocessor.cpp - PP initialization code. ---------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements the clang::InitializePreprocessor function.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/Basic/FileManager.h"
14 #include "clang/Basic/HLSLRuntime.h"
15 #include "clang/Basic/MacroBuilder.h"
16 #include "clang/Basic/SourceManager.h"
17 #include "clang/Basic/SyncScope.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/Frontend/Utils.h"
23 #include "clang/Lex/HeaderSearch.h"
24 #include "clang/Lex/Preprocessor.h"
25 #include "clang/Lex/PreprocessorOptions.h"
26 #include "clang/Serialization/ASTReader.h"
27 #include "llvm/ADT/APFloat.h"
28 #include "llvm/IR/DataLayout.h"
29 #include "llvm/IR/DerivedTypes.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 /// As these includes are generated by -include arguments the header search
69 /// logic is going to search relatively to the current working directory.
70 static void AddImplicitInclude(MacroBuilder &Builder, StringRef File) {
71   Builder.append(Twine("#include \"") + File + "\"");
72 }
73 
74 static void AddImplicitIncludeMacros(MacroBuilder &Builder, StringRef File) {
75   Builder.append(Twine("#__include_macros \"") + File + "\"");
76   // Marker token to stop the __include_macros fetch loop.
77   Builder.append("##"); // ##?
78 }
79 
80 /// Add an implicit \#include using the original file used to generate
81 /// a PCH file.
82 static void AddImplicitIncludePCH(MacroBuilder &Builder, Preprocessor &PP,
83                                   const PCHContainerReader &PCHContainerRdr,
84                                   StringRef ImplicitIncludePCH) {
85   std::string OriginalFile = ASTReader::getOriginalSourceFile(
86       std::string(ImplicitIncludePCH), PP.getFileManager(), PCHContainerRdr,
87       PP.getDiagnostics());
88   if (OriginalFile.empty())
89     return;
90 
91   AddImplicitInclude(Builder, OriginalFile);
92 }
93 
94 /// PickFP - This is used to pick a value based on the FP semantics of the
95 /// specified FP model.
96 template <typename T>
97 static T PickFP(const llvm::fltSemantics *Sem, T IEEEHalfVal, T IEEESingleVal,
98                 T IEEEDoubleVal, T X87DoubleExtendedVal, T PPCDoubleDoubleVal,
99                 T IEEEQuadVal) {
100   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEhalf())
101     return IEEEHalfVal;
102   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEsingle())
103     return IEEESingleVal;
104   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEdouble())
105     return IEEEDoubleVal;
106   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::x87DoubleExtended())
107     return X87DoubleExtendedVal;
108   if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::PPCDoubleDouble())
109     return PPCDoubleDoubleVal;
110   assert(Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEquad());
111   return IEEEQuadVal;
112 }
113 
114 static void DefineFloatMacros(MacroBuilder &Builder, StringRef Prefix,
115                               const llvm::fltSemantics *Sem, StringRef Ext) {
116   const char *DenormMin, *Epsilon, *Max, *Min;
117   DenormMin = PickFP(Sem, "5.9604644775390625e-8", "1.40129846e-45",
118                      "4.9406564584124654e-324", "3.64519953188247460253e-4951",
119                      "4.94065645841246544176568792868221e-324",
120                      "6.47517511943802511092443895822764655e-4966");
121   int Digits = PickFP(Sem, 3, 6, 15, 18, 31, 33);
122   int DecimalDigits = PickFP(Sem, 5, 9, 17, 21, 33, 36);
123   Epsilon = PickFP(Sem, "9.765625e-4", "1.19209290e-7",
124                    "2.2204460492503131e-16", "1.08420217248550443401e-19",
125                    "4.94065645841246544176568792868221e-324",
126                    "1.92592994438723585305597794258492732e-34");
127   int MantissaDigits = PickFP(Sem, 11, 24, 53, 64, 106, 113);
128   int Min10Exp = PickFP(Sem, -4, -37, -307, -4931, -291, -4931);
129   int Max10Exp = PickFP(Sem, 4, 38, 308, 4932, 308, 4932);
130   int MinExp = PickFP(Sem, -13, -125, -1021, -16381, -968, -16381);
131   int MaxExp = PickFP(Sem, 16, 128, 1024, 16384, 1024, 16384);
132   Min = PickFP(Sem, "6.103515625e-5", "1.17549435e-38", "2.2250738585072014e-308",
133                "3.36210314311209350626e-4932",
134                "2.00416836000897277799610805135016e-292",
135                "3.36210314311209350626267781732175260e-4932");
136   Max = PickFP(Sem, "6.5504e+4", "3.40282347e+38", "1.7976931348623157e+308",
137                "1.18973149535723176502e+4932",
138                "1.79769313486231580793728971405301e+308",
139                "1.18973149535723176508575932662800702e+4932");
140 
141   SmallString<32> DefPrefix;
142   DefPrefix = "__";
143   DefPrefix += Prefix;
144   DefPrefix += "_";
145 
146   Builder.defineMacro(DefPrefix + "DENORM_MIN__", Twine(DenormMin)+Ext);
147   Builder.defineMacro(DefPrefix + "HAS_DENORM__");
148   Builder.defineMacro(DefPrefix + "DIG__", Twine(Digits));
149   Builder.defineMacro(DefPrefix + "DECIMAL_DIG__", Twine(DecimalDigits));
150   Builder.defineMacro(DefPrefix + "EPSILON__", Twine(Epsilon)+Ext);
151   Builder.defineMacro(DefPrefix + "HAS_INFINITY__");
152   Builder.defineMacro(DefPrefix + "HAS_QUIET_NAN__");
153   Builder.defineMacro(DefPrefix + "MANT_DIG__", Twine(MantissaDigits));
154 
155   Builder.defineMacro(DefPrefix + "MAX_10_EXP__", Twine(Max10Exp));
156   Builder.defineMacro(DefPrefix + "MAX_EXP__", Twine(MaxExp));
157   Builder.defineMacro(DefPrefix + "MAX__", Twine(Max)+Ext);
158 
159   Builder.defineMacro(DefPrefix + "MIN_10_EXP__","("+Twine(Min10Exp)+")");
160   Builder.defineMacro(DefPrefix + "MIN_EXP__", "("+Twine(MinExp)+")");
161   Builder.defineMacro(DefPrefix + "MIN__", Twine(Min)+Ext);
162 }
163 
164 
165 /// DefineTypeSize - Emit a macro to the predefines buffer that declares a macro
166 /// named MacroName with the max value for a type with width 'TypeWidth' a
167 /// signedness of 'isSigned' and with a value suffix of 'ValSuffix' (e.g. LL).
168 static void DefineTypeSize(const Twine &MacroName, unsigned TypeWidth,
169                            StringRef ValSuffix, bool isSigned,
170                            MacroBuilder &Builder) {
171   llvm::APInt MaxVal = isSigned ? llvm::APInt::getSignedMaxValue(TypeWidth)
172                                 : llvm::APInt::getMaxValue(TypeWidth);
173   Builder.defineMacro(MacroName, toString(MaxVal, 10, isSigned) + ValSuffix);
174 }
175 
176 /// DefineTypeSize - An overloaded helper that uses TargetInfo to determine
177 /// the width, suffix, and signedness of the given type
178 static void DefineTypeSize(const Twine &MacroName, TargetInfo::IntType Ty,
179                            const TargetInfo &TI, MacroBuilder &Builder) {
180   DefineTypeSize(MacroName, TI.getTypeWidth(Ty), TI.getTypeConstantSuffix(Ty),
181                  TI.isTypeSigned(Ty), Builder);
182 }
183 
184 static void DefineFmt(const LangOptions &LangOpts, const Twine &Prefix,
185                       TargetInfo::IntType Ty, const TargetInfo &TI,
186                       MacroBuilder &Builder) {
187   StringRef FmtModifier = TI.getTypeFormatModifier(Ty);
188   auto Emitter = [&](char Fmt) {
189     Builder.defineMacro(Prefix + "_FMT" + Twine(Fmt) + "__",
190                         Twine("\"") + FmtModifier + Twine(Fmt) + "\"");
191   };
192   bool IsSigned = TI.isTypeSigned(Ty);
193   llvm::for_each(StringRef(IsSigned ? "di" : "ouxX"), Emitter);
194 
195   // C23 added the b and B modifiers for printing binary output of unsigned
196   // integers. Conditionally define those if compiling in C23 mode.
197   if (LangOpts.C23 && !IsSigned)
198     llvm::for_each(StringRef("bB"), Emitter);
199 }
200 
201 static void DefineType(const Twine &MacroName, TargetInfo::IntType Ty,
202                        MacroBuilder &Builder) {
203   Builder.defineMacro(MacroName, TargetInfo::getTypeName(Ty));
204 }
205 
206 static void DefineTypeWidth(const Twine &MacroName, TargetInfo::IntType Ty,
207                             const TargetInfo &TI, MacroBuilder &Builder) {
208   Builder.defineMacro(MacroName, Twine(TI.getTypeWidth(Ty)));
209 }
210 
211 static void DefineTypeSizeof(StringRef MacroName, unsigned BitWidth,
212                              const TargetInfo &TI, MacroBuilder &Builder) {
213   Builder.defineMacro(MacroName,
214                       Twine(BitWidth / TI.getCharWidth()));
215 }
216 
217 // This will generate a macro based on the prefix with `_MAX__` as the suffix
218 // for the max value representable for the type, and a macro with a `_WIDTH__`
219 // suffix for the width of the type.
220 static void DefineTypeSizeAndWidth(const Twine &Prefix, TargetInfo::IntType Ty,
221                                    const TargetInfo &TI,
222                                    MacroBuilder &Builder) {
223   DefineTypeSize(Prefix + "_MAX__", Ty, TI, Builder);
224   DefineTypeWidth(Prefix + "_WIDTH__", Ty, TI, Builder);
225 }
226 
227 static void DefineExactWidthIntType(const LangOptions &LangOpts,
228                                     TargetInfo::IntType Ty,
229                                     const TargetInfo &TI,
230                                     MacroBuilder &Builder) {
231   int TypeWidth = TI.getTypeWidth(Ty);
232   bool IsSigned = TI.isTypeSigned(Ty);
233 
234   // Use the target specified int64 type, when appropriate, so that [u]int64_t
235   // ends up being defined in terms of the correct type.
236   if (TypeWidth == 64)
237     Ty = IsSigned ? TI.getInt64Type() : TI.getUInt64Type();
238 
239   // Use the target specified int16 type when appropriate. Some MCU targets
240   // (such as AVR) have definition of [u]int16_t to [un]signed int.
241   if (TypeWidth == 16)
242     Ty = IsSigned ? TI.getInt16Type() : TI.getUInt16Type();
243 
244   const char *Prefix = IsSigned ? "__INT" : "__UINT";
245 
246   DefineType(Prefix + Twine(TypeWidth) + "_TYPE__", Ty, Builder);
247   DefineFmt(LangOpts, Prefix + Twine(TypeWidth), Ty, TI, Builder);
248 
249   StringRef ConstSuffix(TI.getTypeConstantSuffix(Ty));
250   Builder.defineMacro(Prefix + Twine(TypeWidth) + "_C_SUFFIX__", ConstSuffix);
251 }
252 
253 static void DefineExactWidthIntTypeSize(TargetInfo::IntType Ty,
254                                         const TargetInfo &TI,
255                                         MacroBuilder &Builder) {
256   int TypeWidth = TI.getTypeWidth(Ty);
257   bool IsSigned = TI.isTypeSigned(Ty);
258 
259   // Use the target specified int64 type, when appropriate, so that [u]int64_t
260   // ends up being defined in terms of the correct type.
261   if (TypeWidth == 64)
262     Ty = IsSigned ? TI.getInt64Type() : TI.getUInt64Type();
263 
264   // We don't need to define a _WIDTH macro for the exact-width types because
265   // we already know the width.
266   const char *Prefix = IsSigned ? "__INT" : "__UINT";
267   DefineTypeSize(Prefix + Twine(TypeWidth) + "_MAX__", Ty, TI, Builder);
268 }
269 
270 static void DefineLeastWidthIntType(const LangOptions &LangOpts,
271                                     unsigned TypeWidth, bool IsSigned,
272                                     const TargetInfo &TI,
273                                     MacroBuilder &Builder) {
274   TargetInfo::IntType Ty = TI.getLeastIntTypeByWidth(TypeWidth, IsSigned);
275   if (Ty == TargetInfo::NoInt)
276     return;
277 
278   const char *Prefix = IsSigned ? "__INT_LEAST" : "__UINT_LEAST";
279   DefineType(Prefix + Twine(TypeWidth) + "_TYPE__", Ty, Builder);
280   // We only want the *_WIDTH macro for the signed types to avoid too many
281   // predefined macros (the unsigned width and the signed width are identical.)
282   if (IsSigned)
283     DefineTypeSizeAndWidth(Prefix + Twine(TypeWidth), Ty, TI, Builder);
284   else
285     DefineTypeSize(Prefix + Twine(TypeWidth) + "_MAX__", Ty, TI, Builder);
286   DefineFmt(LangOpts, Prefix + Twine(TypeWidth), Ty, TI, Builder);
287 }
288 
289 static void DefineFastIntType(const LangOptions &LangOpts, unsigned TypeWidth,
290                               bool IsSigned, const TargetInfo &TI,
291                               MacroBuilder &Builder) {
292   // stdint.h currently defines the fast int types as equivalent to the least
293   // types.
294   TargetInfo::IntType Ty = TI.getLeastIntTypeByWidth(TypeWidth, IsSigned);
295   if (Ty == TargetInfo::NoInt)
296     return;
297 
298   const char *Prefix = IsSigned ? "__INT_FAST" : "__UINT_FAST";
299   DefineType(Prefix + Twine(TypeWidth) + "_TYPE__", Ty, Builder);
300   // We only want the *_WIDTH macro for the signed types to avoid too many
301   // predefined macros (the unsigned width and the signed width are identical.)
302   if (IsSigned)
303     DefineTypeSizeAndWidth(Prefix + Twine(TypeWidth), Ty, TI, Builder);
304   else
305     DefineTypeSize(Prefix + Twine(TypeWidth) + "_MAX__", Ty, TI, Builder);
306   DefineFmt(LangOpts, Prefix + Twine(TypeWidth), Ty, TI, Builder);
307 }
308 
309 
310 /// Get the value the ATOMIC_*_LOCK_FREE macro should have for a type with
311 /// the specified properties.
312 static const char *getLockFreeValue(unsigned TypeWidth, const TargetInfo &TI) {
313   // Fully-aligned, power-of-2 sizes no larger than the inline
314   // width will be inlined as lock-free operations.
315   // Note: we do not need to check alignment since _Atomic(T) is always
316   // appropriately-aligned in clang.
317   if (TI.hasBuiltinAtomic(TypeWidth, TypeWidth))
318     return "2"; // "always lock free"
319   // We cannot be certain what operations the lib calls might be
320   // able to implement as lock-free on future processors.
321   return "1"; // "sometimes lock free"
322 }
323 
324 /// Add definitions required for a smooth interaction between
325 /// Objective-C++ automated reference counting and libstdc++ (4.2).
326 static void AddObjCXXARCLibstdcxxDefines(const LangOptions &LangOpts,
327                                          MacroBuilder &Builder) {
328   Builder.defineMacro("_GLIBCXX_PREDEFINED_OBJC_ARC_IS_SCALAR");
329 
330   std::string Result;
331   {
332     // Provide specializations for the __is_scalar type trait so that
333     // lifetime-qualified objects are not considered "scalar" types, which
334     // libstdc++ uses as an indicator of the presence of trivial copy, assign,
335     // default-construct, and destruct semantics (none of which hold for
336     // lifetime-qualified objects in ARC).
337     llvm::raw_string_ostream Out(Result);
338 
339     Out << "namespace std {\n"
340         << "\n"
341         << "struct __true_type;\n"
342         << "struct __false_type;\n"
343         << "\n";
344 
345     Out << "template<typename _Tp> struct __is_scalar;\n"
346         << "\n";
347 
348     if (LangOpts.ObjCAutoRefCount) {
349       Out << "template<typename _Tp>\n"
350           << "struct __is_scalar<__attribute__((objc_ownership(strong))) _Tp> {\n"
351           << "  enum { __value = 0 };\n"
352           << "  typedef __false_type __type;\n"
353           << "};\n"
354           << "\n";
355     }
356 
357     if (LangOpts.ObjCWeak) {
358       Out << "template<typename _Tp>\n"
359           << "struct __is_scalar<__attribute__((objc_ownership(weak))) _Tp> {\n"
360           << "  enum { __value = 0 };\n"
361           << "  typedef __false_type __type;\n"
362           << "};\n"
363           << "\n";
364     }
365 
366     if (LangOpts.ObjCAutoRefCount) {
367       Out << "template<typename _Tp>\n"
368           << "struct __is_scalar<__attribute__((objc_ownership(autoreleasing)))"
369           << " _Tp> {\n"
370           << "  enum { __value = 0 };\n"
371           << "  typedef __false_type __type;\n"
372           << "};\n"
373           << "\n";
374     }
375 
376     Out << "}\n";
377   }
378   Builder.append(Result);
379 }
380 
381 static void InitializeStandardPredefinedMacros(const TargetInfo &TI,
382                                                const LangOptions &LangOpts,
383                                                const FrontendOptions &FEOpts,
384                                                MacroBuilder &Builder) {
385   if (LangOpts.HLSL) {
386     Builder.defineMacro("__hlsl_clang");
387     // HLSL Version
388     Builder.defineMacro("__HLSL_VERSION",
389                         Twine((unsigned)LangOpts.getHLSLVersion()));
390 
391     if (LangOpts.NativeHalfType)
392       Builder.defineMacro("__HLSL_ENABLE_16_BIT",
393                           Twine((unsigned)LangOpts.getHLSLVersion()));
394 
395     // Shader target information
396     // "enums" for shader stages
397     Builder.defineMacro("__SHADER_STAGE_VERTEX",
398                         Twine((uint32_t)ShaderStage::Vertex));
399     Builder.defineMacro("__SHADER_STAGE_PIXEL",
400                         Twine((uint32_t)ShaderStage::Pixel));
401     Builder.defineMacro("__SHADER_STAGE_GEOMETRY",
402                         Twine((uint32_t)ShaderStage::Geometry));
403     Builder.defineMacro("__SHADER_STAGE_HULL",
404                         Twine((uint32_t)ShaderStage::Hull));
405     Builder.defineMacro("__SHADER_STAGE_DOMAIN",
406                         Twine((uint32_t)ShaderStage::Domain));
407     Builder.defineMacro("__SHADER_STAGE_COMPUTE",
408                         Twine((uint32_t)ShaderStage::Compute));
409     Builder.defineMacro("__SHADER_STAGE_AMPLIFICATION",
410                         Twine((uint32_t)ShaderStage::Amplification));
411     Builder.defineMacro("__SHADER_STAGE_MESH",
412                         Twine((uint32_t)ShaderStage::Mesh));
413     Builder.defineMacro("__SHADER_STAGE_LIBRARY",
414                         Twine((uint32_t)ShaderStage::Library));
415     // The current shader stage itself
416     uint32_t StageInteger = static_cast<uint32_t>(
417         hlsl::getStageFromEnvironment(TI.getTriple().getEnvironment()));
418 
419     Builder.defineMacro("__SHADER_TARGET_STAGE", Twine(StageInteger));
420     // Add target versions
421     if (TI.getTriple().getOS() == llvm::Triple::ShaderModel) {
422       VersionTuple Version = TI.getTriple().getOSVersion();
423       Builder.defineMacro("__SHADER_TARGET_MAJOR", Twine(Version.getMajor()));
424       unsigned Minor = Version.getMinor().value_or(0);
425       Builder.defineMacro("__SHADER_TARGET_MINOR", Twine(Minor));
426     }
427     return;
428   }
429   // C++ [cpp.predefined]p1:
430   //   The following macro names shall be defined by the implementation:
431 
432   //   -- __STDC__
433   //      [C++] Whether __STDC__ is predefined and if so, what its value is,
434   //      are implementation-defined.
435   // (Removed in C++20.)
436   if (!LangOpts.MSVCCompat && !LangOpts.TraditionalCPP)
437     Builder.defineMacro("__STDC__");
438   //   -- __STDC_HOSTED__
439   //      The integer literal 1 if the implementation is a hosted
440   //      implementation or the integer literal 0 if it is not.
441   if (LangOpts.Freestanding)
442     Builder.defineMacro("__STDC_HOSTED__", "0");
443   else
444     Builder.defineMacro("__STDC_HOSTED__");
445 
446   //   -- __STDC_VERSION__
447   //      [C++] Whether __STDC_VERSION__ is predefined and if so, what its
448   //      value is, are implementation-defined.
449   // (Removed in C++20.)
450   if (!LangOpts.CPlusPlus) {
451     if (LangOpts.C23)
452       Builder.defineMacro("__STDC_VERSION__", "202311L");
453     else if (LangOpts.C17)
454       Builder.defineMacro("__STDC_VERSION__", "201710L");
455     else if (LangOpts.C11)
456       Builder.defineMacro("__STDC_VERSION__", "201112L");
457     else if (LangOpts.C99)
458       Builder.defineMacro("__STDC_VERSION__", "199901L");
459     else if (!LangOpts.GNUMode && LangOpts.Digraphs)
460       Builder.defineMacro("__STDC_VERSION__", "199409L");
461   } else {
462     //   -- __cplusplus
463     if (LangOpts.CPlusPlus26)
464       // FIXME: Use correct value for C++26.
465       Builder.defineMacro("__cplusplus", "202400L");
466     else if (LangOpts.CPlusPlus23)
467       Builder.defineMacro("__cplusplus", "202302L");
468     //      [C++20] The integer literal 202002L.
469     else if (LangOpts.CPlusPlus20)
470       Builder.defineMacro("__cplusplus", "202002L");
471     //      [C++17] The integer literal 201703L.
472     else if (LangOpts.CPlusPlus17)
473       Builder.defineMacro("__cplusplus", "201703L");
474     //      [C++14] The name __cplusplus is defined to the value 201402L when
475     //      compiling a C++ translation unit.
476     else if (LangOpts.CPlusPlus14)
477       Builder.defineMacro("__cplusplus", "201402L");
478     //      [C++11] The name __cplusplus is defined to the value 201103L when
479     //      compiling a C++ translation unit.
480     else if (LangOpts.CPlusPlus11)
481       Builder.defineMacro("__cplusplus", "201103L");
482     //      [C++03] The name __cplusplus is defined to the value 199711L when
483     //      compiling a C++ translation unit.
484     else
485       Builder.defineMacro("__cplusplus", "199711L");
486 
487     //   -- __STDCPP_DEFAULT_NEW_ALIGNMENT__
488     //      [C++17] An integer literal of type std::size_t whose value is the
489     //      alignment guaranteed by a call to operator new(std::size_t)
490     //
491     // We provide this in all language modes, since it seems generally useful.
492     Builder.defineMacro("__STDCPP_DEFAULT_NEW_ALIGNMENT__",
493                         Twine(TI.getNewAlign() / TI.getCharWidth()) +
494                             TI.getTypeConstantSuffix(TI.getSizeType()));
495 
496     //   -- __STDCPP_­THREADS__
497     //      Defined, and has the value integer literal 1, if and only if a
498     //      program can have more than one thread of execution.
499     if (LangOpts.getThreadModel() == LangOptions::ThreadModelKind::POSIX)
500       Builder.defineMacro("__STDCPP_THREADS__", "1");
501   }
502 
503   // In C11 these are environment macros. In C++11 they are only defined
504   // as part of <cuchar>. To prevent breakage when mixing C and C++
505   // code, define these macros unconditionally. We can define them
506   // unconditionally, as Clang always uses UTF-16 and UTF-32 for 16-bit
507   // and 32-bit character literals.
508   Builder.defineMacro("__STDC_UTF_16__", "1");
509   Builder.defineMacro("__STDC_UTF_32__", "1");
510 
511   if (LangOpts.ObjC)
512     Builder.defineMacro("__OBJC__");
513 
514   // OpenCL v1.0/1.1 s6.9, v1.2/2.0 s6.10: Preprocessor Directives and Macros.
515   if (LangOpts.OpenCL) {
516     if (LangOpts.CPlusPlus) {
517       switch (LangOpts.OpenCLCPlusPlusVersion) {
518       case 100:
519         Builder.defineMacro("__OPENCL_CPP_VERSION__", "100");
520         break;
521       case 202100:
522         Builder.defineMacro("__OPENCL_CPP_VERSION__", "202100");
523         break;
524       default:
525         llvm_unreachable("Unsupported C++ version for OpenCL");
526       }
527       Builder.defineMacro("__CL_CPP_VERSION_1_0__", "100");
528       Builder.defineMacro("__CL_CPP_VERSION_2021__", "202100");
529     } else {
530       // OpenCL v1.0 and v1.1 do not have a predefined macro to indicate the
531       // language standard with which the program is compiled. __OPENCL_VERSION__
532       // is for the OpenCL version supported by the OpenCL device, which is not
533       // necessarily the language standard with which the program is compiled.
534       // A shared OpenCL header file requires a macro to indicate the language
535       // standard. As a workaround, __OPENCL_C_VERSION__ is defined for
536       // OpenCL v1.0 and v1.1.
537       switch (LangOpts.OpenCLVersion) {
538       case 100:
539         Builder.defineMacro("__OPENCL_C_VERSION__", "100");
540         break;
541       case 110:
542         Builder.defineMacro("__OPENCL_C_VERSION__", "110");
543         break;
544       case 120:
545         Builder.defineMacro("__OPENCL_C_VERSION__", "120");
546         break;
547       case 200:
548         Builder.defineMacro("__OPENCL_C_VERSION__", "200");
549         break;
550       case 300:
551         Builder.defineMacro("__OPENCL_C_VERSION__", "300");
552         break;
553       default:
554         llvm_unreachable("Unsupported OpenCL version");
555       }
556     }
557     Builder.defineMacro("CL_VERSION_1_0", "100");
558     Builder.defineMacro("CL_VERSION_1_1", "110");
559     Builder.defineMacro("CL_VERSION_1_2", "120");
560     Builder.defineMacro("CL_VERSION_2_0", "200");
561     Builder.defineMacro("CL_VERSION_3_0", "300");
562 
563     if (TI.isLittleEndian())
564       Builder.defineMacro("__ENDIAN_LITTLE__");
565 
566     if (LangOpts.FastRelaxedMath)
567       Builder.defineMacro("__FAST_RELAXED_MATH__");
568   }
569 
570   if (LangOpts.SYCLIsDevice || LangOpts.SYCLIsHost) {
571     // SYCL Version is set to a value when building SYCL applications
572     if (LangOpts.getSYCLVersion() == LangOptions::SYCL_2017)
573       Builder.defineMacro("CL_SYCL_LANGUAGE_VERSION", "121");
574     else if (LangOpts.getSYCLVersion() == LangOptions::SYCL_2020)
575       Builder.defineMacro("SYCL_LANGUAGE_VERSION", "202001");
576   }
577 
578   // Not "standard" per se, but available even with the -undef flag.
579   if (LangOpts.AsmPreprocessor)
580     Builder.defineMacro("__ASSEMBLER__");
581   if (LangOpts.CUDA) {
582     if (LangOpts.GPURelocatableDeviceCode)
583       Builder.defineMacro("__CLANG_RDC__");
584     if (!LangOpts.HIP)
585       Builder.defineMacro("__CUDA__");
586     if (LangOpts.GPUDefaultStream ==
587         LangOptions::GPUDefaultStreamKind::PerThread)
588       Builder.defineMacro("CUDA_API_PER_THREAD_DEFAULT_STREAM");
589   }
590   if (LangOpts.HIP) {
591     Builder.defineMacro("__HIP__");
592     Builder.defineMacro("__HIPCC__");
593     Builder.defineMacro("__HIP_MEMORY_SCOPE_SINGLETHREAD", "1");
594     Builder.defineMacro("__HIP_MEMORY_SCOPE_WAVEFRONT", "2");
595     Builder.defineMacro("__HIP_MEMORY_SCOPE_WORKGROUP", "3");
596     Builder.defineMacro("__HIP_MEMORY_SCOPE_AGENT", "4");
597     Builder.defineMacro("__HIP_MEMORY_SCOPE_SYSTEM", "5");
598     if (LangOpts.HIPStdPar) {
599       Builder.defineMacro("__HIPSTDPAR__");
600       if (LangOpts.HIPStdParInterposeAlloc)
601         Builder.defineMacro("__HIPSTDPAR_INTERPOSE_ALLOC__");
602     }
603     if (LangOpts.CUDAIsDevice) {
604       Builder.defineMacro("__HIP_DEVICE_COMPILE__");
605       if (!TI.hasHIPImageSupport()) {
606         Builder.defineMacro("__HIP_NO_IMAGE_SUPPORT__", "1");
607         // Deprecated.
608         Builder.defineMacro("__HIP_NO_IMAGE_SUPPORT", "1");
609       }
610     }
611     if (LangOpts.GPUDefaultStream ==
612         LangOptions::GPUDefaultStreamKind::PerThread) {
613       Builder.defineMacro("__HIP_API_PER_THREAD_DEFAULT_STREAM__");
614       // Deprecated.
615       Builder.defineMacro("HIP_API_PER_THREAD_DEFAULT_STREAM");
616     }
617   }
618 
619   if (LangOpts.OpenACC) {
620     // FIXME: When we have full support for OpenACC, we should set this to the
621     // version we support. Until then, set as '1' by default, but provide a
622     // temporary mechanism for users to override this so real-world examples can
623     // be tested against.
624     if (!LangOpts.OpenACCMacroOverride.empty())
625       Builder.defineMacro("_OPENACC", LangOpts.OpenACCMacroOverride);
626     else
627       Builder.defineMacro("_OPENACC", "1");
628   }
629 }
630 
631 /// Initialize the predefined C++ language feature test macros defined in
632 /// ISO/IEC JTC1/SC22/WG21 (C++) SD-6: "SG10 Feature Test Recommendations".
633 static void InitializeCPlusPlusFeatureTestMacros(const LangOptions &LangOpts,
634                                                  MacroBuilder &Builder) {
635   // C++98 features.
636   if (LangOpts.RTTI)
637     Builder.defineMacro("__cpp_rtti", "199711L");
638   if (LangOpts.CXXExceptions)
639     Builder.defineMacro("__cpp_exceptions", "199711L");
640 
641   // C++11 features.
642   if (LangOpts.CPlusPlus11) {
643     Builder.defineMacro("__cpp_unicode_characters", "200704L");
644     Builder.defineMacro("__cpp_raw_strings", "200710L");
645     Builder.defineMacro("__cpp_unicode_literals", "200710L");
646     Builder.defineMacro("__cpp_user_defined_literals", "200809L");
647     Builder.defineMacro("__cpp_lambdas", "200907L");
648     Builder.defineMacro("__cpp_constexpr", LangOpts.CPlusPlus26   ? "202306L"
649                                            : LangOpts.CPlusPlus23 ? "202211L"
650                                            : LangOpts.CPlusPlus20 ? "201907L"
651                                            : LangOpts.CPlusPlus17 ? "201603L"
652                                            : LangOpts.CPlusPlus14 ? "201304L"
653                                                                   : "200704");
654     Builder.defineMacro("__cpp_constexpr_in_decltype", "201711L");
655     Builder.defineMacro("__cpp_range_based_for",
656                         LangOpts.CPlusPlus23   ? "202211L"
657                         : LangOpts.CPlusPlus17 ? "201603L"
658                                                : "200907");
659     Builder.defineMacro("__cpp_static_assert", LangOpts.CPlusPlus26 ? "202306L"
660                                                : LangOpts.CPlusPlus17
661                                                    ? "201411L"
662                                                    : "200410");
663     Builder.defineMacro("__cpp_decltype", "200707L");
664     Builder.defineMacro("__cpp_attributes", "200809L");
665     Builder.defineMacro("__cpp_rvalue_references", "200610L");
666     Builder.defineMacro("__cpp_variadic_templates", "200704L");
667     Builder.defineMacro("__cpp_initializer_lists", "200806L");
668     Builder.defineMacro("__cpp_delegating_constructors", "200604L");
669     Builder.defineMacro("__cpp_nsdmi", "200809L");
670     Builder.defineMacro("__cpp_inheriting_constructors", "201511L");
671     Builder.defineMacro("__cpp_ref_qualifiers", "200710L");
672     Builder.defineMacro("__cpp_alias_templates", "200704L");
673   }
674   if (LangOpts.ThreadsafeStatics)
675     Builder.defineMacro("__cpp_threadsafe_static_init", "200806L");
676 
677   // C++14 features.
678   if (LangOpts.CPlusPlus14) {
679     Builder.defineMacro("__cpp_binary_literals", "201304L");
680     Builder.defineMacro("__cpp_digit_separators", "201309L");
681     Builder.defineMacro("__cpp_init_captures",
682                         LangOpts.CPlusPlus20 ? "201803L" : "201304L");
683     Builder.defineMacro("__cpp_generic_lambdas",
684                         LangOpts.CPlusPlus20 ? "201707L" : "201304L");
685     Builder.defineMacro("__cpp_decltype_auto", "201304L");
686     Builder.defineMacro("__cpp_return_type_deduction", "201304L");
687     Builder.defineMacro("__cpp_aggregate_nsdmi", "201304L");
688     Builder.defineMacro("__cpp_variable_templates", "201304L");
689   }
690   if (LangOpts.SizedDeallocation)
691     Builder.defineMacro("__cpp_sized_deallocation", "201309L");
692 
693   // C++17 features.
694   if (LangOpts.CPlusPlus17) {
695     Builder.defineMacro("__cpp_hex_float", "201603L");
696     Builder.defineMacro("__cpp_inline_variables", "201606L");
697     Builder.defineMacro("__cpp_noexcept_function_type", "201510L");
698     Builder.defineMacro("__cpp_capture_star_this", "201603L");
699     Builder.defineMacro("__cpp_if_constexpr", "201606L");
700     Builder.defineMacro("__cpp_deduction_guides", "201703L"); // (not latest)
701     Builder.defineMacro("__cpp_template_auto", "201606L"); // (old name)
702     Builder.defineMacro("__cpp_namespace_attributes", "201411L");
703     Builder.defineMacro("__cpp_enumerator_attributes", "201411L");
704     Builder.defineMacro("__cpp_nested_namespace_definitions", "201411L");
705     Builder.defineMacro("__cpp_variadic_using", "201611L");
706     Builder.defineMacro("__cpp_aggregate_bases", "201603L");
707     Builder.defineMacro("__cpp_structured_bindings", "201606L");
708     Builder.defineMacro("__cpp_nontype_template_args",
709                         "201411L"); // (not latest)
710     Builder.defineMacro("__cpp_fold_expressions", "201603L");
711     Builder.defineMacro("__cpp_guaranteed_copy_elision", "201606L");
712     Builder.defineMacro("__cpp_nontype_template_parameter_auto", "201606L");
713   }
714   if (LangOpts.AlignedAllocation && !LangOpts.AlignedAllocationUnavailable)
715     Builder.defineMacro("__cpp_aligned_new", "201606L");
716   if (LangOpts.RelaxedTemplateTemplateArgs)
717     Builder.defineMacro("__cpp_template_template_args", "201611L");
718 
719   // C++20 features.
720   if (LangOpts.CPlusPlus20) {
721     Builder.defineMacro("__cpp_aggregate_paren_init", "201902L");
722 
723     Builder.defineMacro("__cpp_concepts", "202002");
724     Builder.defineMacro("__cpp_conditional_explicit", "201806L");
725     Builder.defineMacro("__cpp_consteval", "202211L");
726     Builder.defineMacro("__cpp_constexpr_dynamic_alloc", "201907L");
727     Builder.defineMacro("__cpp_constinit", "201907L");
728     Builder.defineMacro("__cpp_impl_coroutine", "201902L");
729     Builder.defineMacro("__cpp_designated_initializers", "201707L");
730     Builder.defineMacro("__cpp_impl_three_way_comparison", "201907L");
731     //Builder.defineMacro("__cpp_modules", "201907L");
732     Builder.defineMacro("__cpp_using_enum", "201907L");
733   }
734   // C++23 features.
735   if (LangOpts.CPlusPlus23) {
736     Builder.defineMacro("__cpp_implicit_move", "202207L");
737     Builder.defineMacro("__cpp_size_t_suffix", "202011L");
738     Builder.defineMacro("__cpp_if_consteval", "202106L");
739     Builder.defineMacro("__cpp_multidimensional_subscript", "202211L");
740     Builder.defineMacro("__cpp_auto_cast", "202110L");
741   }
742 
743   // We provide those C++23 features as extensions in earlier language modes, so
744   // we also define their feature test macros.
745   if (LangOpts.CPlusPlus11)
746     Builder.defineMacro("__cpp_static_call_operator", "202207L");
747   Builder.defineMacro("__cpp_named_character_escapes", "202207L");
748   Builder.defineMacro("__cpp_placeholder_variables", "202306L");
749 
750   if (LangOpts.Char8)
751     Builder.defineMacro("__cpp_char8_t", "202207L");
752   Builder.defineMacro("__cpp_impl_destroying_delete", "201806L");
753 }
754 
755 /// InitializeOpenCLFeatureTestMacros - Define OpenCL macros based on target
756 /// settings and language version
757 void InitializeOpenCLFeatureTestMacros(const TargetInfo &TI,
758                                        const LangOptions &Opts,
759                                        MacroBuilder &Builder) {
760   const llvm::StringMap<bool> &OpenCLFeaturesMap = TI.getSupportedOpenCLOpts();
761   // FIXME: OpenCL options which affect language semantics/syntax
762   // should be moved into LangOptions.
763   auto defineOpenCLExtMacro = [&](llvm::StringRef Name, auto... OptArgs) {
764     // Check if extension is supported by target and is available in this
765     // OpenCL version
766     if (TI.hasFeatureEnabled(OpenCLFeaturesMap, Name) &&
767         OpenCLOptions::isOpenCLOptionAvailableIn(Opts, OptArgs...))
768       Builder.defineMacro(Name);
769   };
770 #define OPENCL_GENERIC_EXTENSION(Ext, ...)                                     \
771   defineOpenCLExtMacro(#Ext, __VA_ARGS__);
772 #include "clang/Basic/OpenCLExtensions.def"
773 
774   // Assume compiling for FULL profile
775   Builder.defineMacro("__opencl_c_int64");
776 }
777 
778 llvm::SmallString<32> ConstructFixedPointLiteral(llvm::APFixedPoint Val,
779                                                  llvm::StringRef Suffix) {
780   if (Val.isSigned() && Val == llvm::APFixedPoint::getMin(Val.getSemantics())) {
781     // When representing the min value of a signed fixed point type in source
782     // code, we cannot simply write `-<lowest value>`. For example, the min
783     // value of a `short _Fract` cannot be written as `-1.0hr`. This is because
784     // the parser will read this (and really any negative numerical literal) as
785     // a UnaryOperator that owns a FixedPointLiteral with a positive value
786     // rather than just a FixedPointLiteral with a negative value. Compiling
787     // `-1.0hr` results in an overflow to the maximal value of that fixed point
788     // type. The correct way to represent a signed min value is to instead split
789     // it into two halves, like `(-0.5hr-0.5hr)` which is what the standard
790     // defines SFRACT_MIN as.
791     llvm::SmallString<32> Literal;
792     Literal.push_back('(');
793     llvm::SmallString<32> HalfStr =
794         ConstructFixedPointLiteral(Val.shr(1), Suffix);
795     Literal += HalfStr;
796     Literal += HalfStr;
797     Literal.push_back(')');
798     return Literal;
799   }
800 
801   llvm::SmallString<32> Str(Val.toString());
802   Str += Suffix;
803   return Str;
804 }
805 
806 void DefineFixedPointMacros(const TargetInfo &TI, MacroBuilder &Builder,
807                             llvm::StringRef TypeName, llvm::StringRef Suffix,
808                             unsigned Width, unsigned Scale, bool Signed) {
809   // Saturation doesn't affect the size or scale of a fixed point type, so we
810   // don't need it here.
811   llvm::FixedPointSemantics FXSema(
812       Width, Scale, Signed, /*IsSaturated=*/false,
813       !Signed && TI.doUnsignedFixedPointTypesHavePadding());
814   llvm::SmallString<32> MacroPrefix("__");
815   MacroPrefix += TypeName;
816   Builder.defineMacro(MacroPrefix + "_EPSILON__",
817                       ConstructFixedPointLiteral(
818                           llvm::APFixedPoint::getEpsilon(FXSema), Suffix));
819   Builder.defineMacro(MacroPrefix + "_FBIT__", Twine(Scale));
820   Builder.defineMacro(
821       MacroPrefix + "_MAX__",
822       ConstructFixedPointLiteral(llvm::APFixedPoint::getMax(FXSema), Suffix));
823 
824   // ISO/IEC TR 18037:2008 doesn't specify MIN macros for unsigned types since
825   // they're all just zero.
826   if (Signed)
827     Builder.defineMacro(
828         MacroPrefix + "_MIN__",
829         ConstructFixedPointLiteral(llvm::APFixedPoint::getMin(FXSema), Suffix));
830 }
831 
832 static void InitializePredefinedMacros(const TargetInfo &TI,
833                                        const LangOptions &LangOpts,
834                                        const FrontendOptions &FEOpts,
835                                        const PreprocessorOptions &PPOpts,
836                                        MacroBuilder &Builder) {
837   // Compiler version introspection macros.
838   Builder.defineMacro("__llvm__");  // LLVM Backend
839   Builder.defineMacro("__clang__"); // Clang Frontend
840 #define TOSTR2(X) #X
841 #define TOSTR(X) TOSTR2(X)
842   Builder.defineMacro("__clang_major__", TOSTR(CLANG_VERSION_MAJOR));
843   Builder.defineMacro("__clang_minor__", TOSTR(CLANG_VERSION_MINOR));
844   Builder.defineMacro("__clang_patchlevel__", TOSTR(CLANG_VERSION_PATCHLEVEL));
845 #undef TOSTR
846 #undef TOSTR2
847   Builder.defineMacro("__clang_version__",
848                       "\"" CLANG_VERSION_STRING " "
849                       + getClangFullRepositoryVersion() + "\"");
850 
851   if (LangOpts.GNUCVersion != 0) {
852     // Major, minor, patch, are given two decimal places each, so 4.2.1 becomes
853     // 40201.
854     unsigned GNUCMajor = LangOpts.GNUCVersion / 100 / 100;
855     unsigned GNUCMinor = LangOpts.GNUCVersion / 100 % 100;
856     unsigned GNUCPatch = LangOpts.GNUCVersion % 100;
857     Builder.defineMacro("__GNUC__", Twine(GNUCMajor));
858     Builder.defineMacro("__GNUC_MINOR__", Twine(GNUCMinor));
859     Builder.defineMacro("__GNUC_PATCHLEVEL__", Twine(GNUCPatch));
860     Builder.defineMacro("__GXX_ABI_VERSION", "1002");
861 
862     if (LangOpts.CPlusPlus) {
863       Builder.defineMacro("__GNUG__", Twine(GNUCMajor));
864       Builder.defineMacro("__GXX_WEAK__");
865     }
866   }
867 
868   // Define macros for the C11 / C++11 memory orderings
869   Builder.defineMacro("__ATOMIC_RELAXED", "0");
870   Builder.defineMacro("__ATOMIC_CONSUME", "1");
871   Builder.defineMacro("__ATOMIC_ACQUIRE", "2");
872   Builder.defineMacro("__ATOMIC_RELEASE", "3");
873   Builder.defineMacro("__ATOMIC_ACQ_REL", "4");
874   Builder.defineMacro("__ATOMIC_SEQ_CST", "5");
875 
876   // Define macros for the clang atomic scopes.
877   Builder.defineMacro("__MEMORY_SCOPE_SYSTEM", "0");
878   Builder.defineMacro("__MEMORY_SCOPE_DEVICE", "1");
879   Builder.defineMacro("__MEMORY_SCOPE_WRKGRP", "2");
880   Builder.defineMacro("__MEMORY_SCOPE_WVFRNT", "3");
881   Builder.defineMacro("__MEMORY_SCOPE_SINGLE", "4");
882 
883   // Define macros for the OpenCL memory scope.
884   // The values should match AtomicScopeOpenCLModel::ID enum.
885   static_assert(
886       static_cast<unsigned>(AtomicScopeOpenCLModel::WorkGroup) == 1 &&
887           static_cast<unsigned>(AtomicScopeOpenCLModel::Device) == 2 &&
888           static_cast<unsigned>(AtomicScopeOpenCLModel::AllSVMDevices) == 3 &&
889           static_cast<unsigned>(AtomicScopeOpenCLModel::SubGroup) == 4,
890       "Invalid OpenCL memory scope enum definition");
891   Builder.defineMacro("__OPENCL_MEMORY_SCOPE_WORK_ITEM", "0");
892   Builder.defineMacro("__OPENCL_MEMORY_SCOPE_WORK_GROUP", "1");
893   Builder.defineMacro("__OPENCL_MEMORY_SCOPE_DEVICE", "2");
894   Builder.defineMacro("__OPENCL_MEMORY_SCOPE_ALL_SVM_DEVICES", "3");
895   Builder.defineMacro("__OPENCL_MEMORY_SCOPE_SUB_GROUP", "4");
896 
897   // Define macros for floating-point data classes, used in __builtin_isfpclass.
898   Builder.defineMacro("__FPCLASS_SNAN", "0x0001");
899   Builder.defineMacro("__FPCLASS_QNAN", "0x0002");
900   Builder.defineMacro("__FPCLASS_NEGINF", "0x0004");
901   Builder.defineMacro("__FPCLASS_NEGNORMAL", "0x0008");
902   Builder.defineMacro("__FPCLASS_NEGSUBNORMAL", "0x0010");
903   Builder.defineMacro("__FPCLASS_NEGZERO", "0x0020");
904   Builder.defineMacro("__FPCLASS_POSZERO", "0x0040");
905   Builder.defineMacro("__FPCLASS_POSSUBNORMAL", "0x0080");
906   Builder.defineMacro("__FPCLASS_POSNORMAL", "0x0100");
907   Builder.defineMacro("__FPCLASS_POSINF", "0x0200");
908 
909   // Support for #pragma redefine_extname (Sun compatibility)
910   Builder.defineMacro("__PRAGMA_REDEFINE_EXTNAME", "1");
911 
912   // Previously this macro was set to a string aiming to achieve compatibility
913   // with GCC 4.2.1. Now, just return the full Clang version
914   Builder.defineMacro("__VERSION__", "\"" +
915                       Twine(getClangFullCPPVersion()) + "\"");
916 
917   // Initialize language-specific preprocessor defines.
918 
919   // Standard conforming mode?
920   if (!LangOpts.GNUMode && !LangOpts.MSVCCompat)
921     Builder.defineMacro("__STRICT_ANSI__");
922 
923   if (LangOpts.GNUCVersion && LangOpts.CPlusPlus11)
924     Builder.defineMacro("__GXX_EXPERIMENTAL_CXX0X__");
925 
926   if (LangOpts.ObjC) {
927     if (LangOpts.ObjCRuntime.isNonFragile()) {
928       Builder.defineMacro("__OBJC2__");
929 
930       if (LangOpts.ObjCExceptions)
931         Builder.defineMacro("OBJC_ZEROCOST_EXCEPTIONS");
932     }
933 
934     if (LangOpts.getGC() != LangOptions::NonGC)
935       Builder.defineMacro("__OBJC_GC__");
936 
937     if (LangOpts.ObjCRuntime.isNeXTFamily())
938       Builder.defineMacro("__NEXT_RUNTIME__");
939 
940     if (LangOpts.ObjCRuntime.getKind() == ObjCRuntime::GNUstep) {
941       auto version = LangOpts.ObjCRuntime.getVersion();
942       std::string versionString = "1";
943       // Don't rely on the tuple argument, because we can be asked to target
944       // later ABIs than we actually support, so clamp these values to those
945       // currently supported
946       if (version >= VersionTuple(2, 0))
947         Builder.defineMacro("__OBJC_GNUSTEP_RUNTIME_ABI__", "20");
948       else
949         Builder.defineMacro(
950             "__OBJC_GNUSTEP_RUNTIME_ABI__",
951             "1" + Twine(std::min(8U, version.getMinor().value_or(0))));
952     }
953 
954     if (LangOpts.ObjCRuntime.getKind() == ObjCRuntime::ObjFW) {
955       VersionTuple tuple = LangOpts.ObjCRuntime.getVersion();
956       unsigned minor = tuple.getMinor().value_or(0);
957       unsigned subminor = tuple.getSubminor().value_or(0);
958       Builder.defineMacro("__OBJFW_RUNTIME_ABI__",
959                           Twine(tuple.getMajor() * 10000 + minor * 100 +
960                                 subminor));
961     }
962 
963     Builder.defineMacro("IBOutlet", "__attribute__((iboutlet))");
964     Builder.defineMacro("IBOutletCollection(ClassName)",
965                         "__attribute__((iboutletcollection(ClassName)))");
966     Builder.defineMacro("IBAction", "void)__attribute__((ibaction)");
967     Builder.defineMacro("IBInspectable", "");
968     Builder.defineMacro("IB_DESIGNABLE", "");
969   }
970 
971   // Define a macro that describes the Objective-C boolean type even for C
972   // and C++ since BOOL can be used from non Objective-C code.
973   Builder.defineMacro("__OBJC_BOOL_IS_BOOL",
974                       Twine(TI.useSignedCharForObjCBool() ? "0" : "1"));
975 
976   if (LangOpts.CPlusPlus)
977     InitializeCPlusPlusFeatureTestMacros(LangOpts, Builder);
978 
979   // darwin_constant_cfstrings controls this. This is also dependent
980   // on other things like the runtime I believe.  This is set even for C code.
981   if (!LangOpts.NoConstantCFStrings)
982       Builder.defineMacro("__CONSTANT_CFSTRINGS__");
983 
984   if (LangOpts.ObjC)
985     Builder.defineMacro("OBJC_NEW_PROPERTIES");
986 
987   if (LangOpts.PascalStrings)
988     Builder.defineMacro("__PASCAL_STRINGS__");
989 
990   if (LangOpts.Blocks) {
991     Builder.defineMacro("__block", "__attribute__((__blocks__(byref)))");
992     Builder.defineMacro("__BLOCKS__");
993   }
994 
995   if (!LangOpts.MSVCCompat && LangOpts.Exceptions)
996     Builder.defineMacro("__EXCEPTIONS");
997   if (LangOpts.GNUCVersion && LangOpts.RTTI)
998     Builder.defineMacro("__GXX_RTTI");
999 
1000   if (LangOpts.hasSjLjExceptions())
1001     Builder.defineMacro("__USING_SJLJ_EXCEPTIONS__");
1002   else if (LangOpts.hasSEHExceptions())
1003     Builder.defineMacro("__SEH__");
1004   else if (LangOpts.hasDWARFExceptions() &&
1005            (TI.getTriple().isThumb() || TI.getTriple().isARM()))
1006     Builder.defineMacro("__ARM_DWARF_EH__");
1007 
1008   if (LangOpts.Deprecated)
1009     Builder.defineMacro("__DEPRECATED");
1010 
1011   if (!LangOpts.MSVCCompat && LangOpts.CPlusPlus)
1012     Builder.defineMacro("__private_extern__", "extern");
1013 
1014   if (LangOpts.MicrosoftExt) {
1015     if (LangOpts.WChar) {
1016       // wchar_t supported as a keyword.
1017       Builder.defineMacro("_WCHAR_T_DEFINED");
1018       Builder.defineMacro("_NATIVE_WCHAR_T_DEFINED");
1019     }
1020   }
1021 
1022   // Macros to help identify the narrow and wide character sets
1023   // FIXME: clang currently ignores -fexec-charset=. If this changes,
1024   // then this may need to be updated.
1025   Builder.defineMacro("__clang_literal_encoding__", "\"UTF-8\"");
1026   if (TI.getTypeWidth(TI.getWCharType()) >= 32) {
1027     // FIXME: 32-bit wchar_t signals UTF-32. This may change
1028     // if -fwide-exec-charset= is ever supported.
1029     Builder.defineMacro("__clang_wide_literal_encoding__", "\"UTF-32\"");
1030   } else {
1031     // FIXME: Less-than 32-bit wchar_t generally means UTF-16
1032     // (e.g., Windows, 32-bit IBM). This may need to be
1033     // updated if -fwide-exec-charset= is ever supported.
1034     Builder.defineMacro("__clang_wide_literal_encoding__", "\"UTF-16\"");
1035   }
1036 
1037   if (LangOpts.Optimize)
1038     Builder.defineMacro("__OPTIMIZE__");
1039   if (LangOpts.OptimizeSize)
1040     Builder.defineMacro("__OPTIMIZE_SIZE__");
1041 
1042   if (LangOpts.FastMath)
1043     Builder.defineMacro("__FAST_MATH__");
1044 
1045   // Initialize target-specific preprocessor defines.
1046 
1047   // __BYTE_ORDER__ was added in GCC 4.6. It's analogous
1048   // to the macro __BYTE_ORDER (no trailing underscores)
1049   // from glibc's <endian.h> header.
1050   // We don't support the PDP-11 as a target, but include
1051   // the define so it can still be compared against.
1052   Builder.defineMacro("__ORDER_LITTLE_ENDIAN__", "1234");
1053   Builder.defineMacro("__ORDER_BIG_ENDIAN__",    "4321");
1054   Builder.defineMacro("__ORDER_PDP_ENDIAN__",    "3412");
1055   if (TI.isBigEndian()) {
1056     Builder.defineMacro("__BYTE_ORDER__", "__ORDER_BIG_ENDIAN__");
1057     Builder.defineMacro("__BIG_ENDIAN__");
1058   } else {
1059     Builder.defineMacro("__BYTE_ORDER__", "__ORDER_LITTLE_ENDIAN__");
1060     Builder.defineMacro("__LITTLE_ENDIAN__");
1061   }
1062 
1063   if (TI.getPointerWidth(LangAS::Default) == 64 && TI.getLongWidth() == 64 &&
1064       TI.getIntWidth() == 32) {
1065     Builder.defineMacro("_LP64");
1066     Builder.defineMacro("__LP64__");
1067   }
1068 
1069   if (TI.getPointerWidth(LangAS::Default) == 32 && TI.getLongWidth() == 32 &&
1070       TI.getIntWidth() == 32) {
1071     Builder.defineMacro("_ILP32");
1072     Builder.defineMacro("__ILP32__");
1073   }
1074 
1075   // Define type sizing macros based on the target properties.
1076   assert(TI.getCharWidth() == 8 && "Only support 8-bit char so far");
1077   Builder.defineMacro("__CHAR_BIT__", Twine(TI.getCharWidth()));
1078 
1079   Builder.defineMacro("__BOOL_WIDTH__", Twine(TI.getBoolWidth()));
1080   Builder.defineMacro("__SHRT_WIDTH__", Twine(TI.getShortWidth()));
1081   Builder.defineMacro("__INT_WIDTH__", Twine(TI.getIntWidth()));
1082   Builder.defineMacro("__LONG_WIDTH__", Twine(TI.getLongWidth()));
1083   Builder.defineMacro("__LLONG_WIDTH__", Twine(TI.getLongLongWidth()));
1084 
1085   size_t BitIntMaxWidth = TI.getMaxBitIntWidth();
1086   assert(BitIntMaxWidth <= llvm::IntegerType::MAX_INT_BITS &&
1087          "Target defined a max bit width larger than LLVM can support!");
1088   assert(BitIntMaxWidth >= TI.getLongLongWidth() &&
1089          "Target defined a max bit width smaller than the C standard allows!");
1090   Builder.defineMacro("__BITINT_MAXWIDTH__", Twine(BitIntMaxWidth));
1091 
1092   DefineTypeSize("__SCHAR_MAX__", TargetInfo::SignedChar, TI, Builder);
1093   DefineTypeSize("__SHRT_MAX__", TargetInfo::SignedShort, TI, Builder);
1094   DefineTypeSize("__INT_MAX__", TargetInfo::SignedInt, TI, Builder);
1095   DefineTypeSize("__LONG_MAX__", TargetInfo::SignedLong, TI, Builder);
1096   DefineTypeSize("__LONG_LONG_MAX__", TargetInfo::SignedLongLong, TI, Builder);
1097   DefineTypeSizeAndWidth("__WCHAR", TI.getWCharType(), TI, Builder);
1098   DefineTypeSizeAndWidth("__WINT", TI.getWIntType(), TI, Builder);
1099   DefineTypeSizeAndWidth("__INTMAX", TI.getIntMaxType(), TI, Builder);
1100   DefineTypeSizeAndWidth("__SIZE", TI.getSizeType(), TI, Builder);
1101 
1102   DefineTypeSizeAndWidth("__UINTMAX", TI.getUIntMaxType(), TI, Builder);
1103   DefineTypeSizeAndWidth("__PTRDIFF", TI.getPtrDiffType(LangAS::Default), TI,
1104                          Builder);
1105   DefineTypeSizeAndWidth("__INTPTR", TI.getIntPtrType(), TI, Builder);
1106   DefineTypeSizeAndWidth("__UINTPTR", TI.getUIntPtrType(), TI, Builder);
1107 
1108   DefineTypeSizeof("__SIZEOF_DOUBLE__", TI.getDoubleWidth(), TI, Builder);
1109   DefineTypeSizeof("__SIZEOF_FLOAT__", TI.getFloatWidth(), TI, Builder);
1110   DefineTypeSizeof("__SIZEOF_INT__", TI.getIntWidth(), TI, Builder);
1111   DefineTypeSizeof("__SIZEOF_LONG__", TI.getLongWidth(), TI, Builder);
1112   DefineTypeSizeof("__SIZEOF_LONG_DOUBLE__",TI.getLongDoubleWidth(),TI,Builder);
1113   DefineTypeSizeof("__SIZEOF_LONG_LONG__", TI.getLongLongWidth(), TI, Builder);
1114   DefineTypeSizeof("__SIZEOF_POINTER__", TI.getPointerWidth(LangAS::Default),
1115                    TI, Builder);
1116   DefineTypeSizeof("__SIZEOF_SHORT__", TI.getShortWidth(), TI, Builder);
1117   DefineTypeSizeof("__SIZEOF_PTRDIFF_T__",
1118                    TI.getTypeWidth(TI.getPtrDiffType(LangAS::Default)), TI,
1119                    Builder);
1120   DefineTypeSizeof("__SIZEOF_SIZE_T__",
1121                    TI.getTypeWidth(TI.getSizeType()), TI, Builder);
1122   DefineTypeSizeof("__SIZEOF_WCHAR_T__",
1123                    TI.getTypeWidth(TI.getWCharType()), TI, Builder);
1124   DefineTypeSizeof("__SIZEOF_WINT_T__",
1125                    TI.getTypeWidth(TI.getWIntType()), TI, Builder);
1126   if (TI.hasInt128Type())
1127     DefineTypeSizeof("__SIZEOF_INT128__", 128, TI, Builder);
1128 
1129   DefineType("__INTMAX_TYPE__", TI.getIntMaxType(), Builder);
1130   DefineFmt(LangOpts, "__INTMAX", TI.getIntMaxType(), TI, Builder);
1131   Builder.defineMacro("__INTMAX_C_SUFFIX__",
1132                       TI.getTypeConstantSuffix(TI.getIntMaxType()));
1133   DefineType("__UINTMAX_TYPE__", TI.getUIntMaxType(), Builder);
1134   DefineFmt(LangOpts, "__UINTMAX", TI.getUIntMaxType(), TI, Builder);
1135   Builder.defineMacro("__UINTMAX_C_SUFFIX__",
1136                       TI.getTypeConstantSuffix(TI.getUIntMaxType()));
1137   DefineType("__PTRDIFF_TYPE__", TI.getPtrDiffType(LangAS::Default), Builder);
1138   DefineFmt(LangOpts, "__PTRDIFF", TI.getPtrDiffType(LangAS::Default), TI,
1139             Builder);
1140   DefineType("__INTPTR_TYPE__", TI.getIntPtrType(), Builder);
1141   DefineFmt(LangOpts, "__INTPTR", TI.getIntPtrType(), TI, Builder);
1142   DefineType("__SIZE_TYPE__", TI.getSizeType(), Builder);
1143   DefineFmt(LangOpts, "__SIZE", TI.getSizeType(), TI, Builder);
1144   DefineType("__WCHAR_TYPE__", TI.getWCharType(), Builder);
1145   DefineType("__WINT_TYPE__", TI.getWIntType(), Builder);
1146   DefineTypeSizeAndWidth("__SIG_ATOMIC", TI.getSigAtomicType(), TI, Builder);
1147   DefineType("__CHAR16_TYPE__", TI.getChar16Type(), Builder);
1148   DefineType("__CHAR32_TYPE__", TI.getChar32Type(), Builder);
1149 
1150   DefineType("__UINTPTR_TYPE__", TI.getUIntPtrType(), Builder);
1151   DefineFmt(LangOpts, "__UINTPTR", TI.getUIntPtrType(), TI, Builder);
1152 
1153   // The C standard requires the width of uintptr_t and intptr_t to be the same,
1154   // per 7.20.2.4p1. Same for intmax_t and uintmax_t, per 7.20.2.5p1.
1155   assert(TI.getTypeWidth(TI.getUIntPtrType()) ==
1156              TI.getTypeWidth(TI.getIntPtrType()) &&
1157          "uintptr_t and intptr_t have different widths?");
1158   assert(TI.getTypeWidth(TI.getUIntMaxType()) ==
1159              TI.getTypeWidth(TI.getIntMaxType()) &&
1160          "uintmax_t and intmax_t have different widths?");
1161 
1162   if (LangOpts.FixedPoint) {
1163     // Each unsigned type has the same width as their signed type.
1164     DefineFixedPointMacros(TI, Builder, "SFRACT", "HR", TI.getShortFractWidth(),
1165                            TI.getShortFractScale(), /*Signed=*/true);
1166     DefineFixedPointMacros(TI, Builder, "USFRACT", "UHR",
1167                            TI.getShortFractWidth(),
1168                            TI.getUnsignedShortFractScale(), /*Signed=*/false);
1169     DefineFixedPointMacros(TI, Builder, "FRACT", "R", TI.getFractWidth(),
1170                            TI.getFractScale(), /*Signed=*/true);
1171     DefineFixedPointMacros(TI, Builder, "UFRACT", "UR", TI.getFractWidth(),
1172                            TI.getUnsignedFractScale(), /*Signed=*/false);
1173     DefineFixedPointMacros(TI, Builder, "LFRACT", "LR", TI.getLongFractWidth(),
1174                            TI.getLongFractScale(), /*Signed=*/true);
1175     DefineFixedPointMacros(TI, Builder, "ULFRACT", "ULR",
1176                            TI.getLongFractWidth(),
1177                            TI.getUnsignedLongFractScale(), /*Signed=*/false);
1178     DefineFixedPointMacros(TI, Builder, "SACCUM", "HK", TI.getShortAccumWidth(),
1179                            TI.getShortAccumScale(), /*Signed=*/true);
1180     DefineFixedPointMacros(TI, Builder, "USACCUM", "UHK",
1181                            TI.getShortAccumWidth(),
1182                            TI.getUnsignedShortAccumScale(), /*Signed=*/false);
1183     DefineFixedPointMacros(TI, Builder, "ACCUM", "K", TI.getAccumWidth(),
1184                            TI.getAccumScale(), /*Signed=*/true);
1185     DefineFixedPointMacros(TI, Builder, "UACCUM", "UK", TI.getAccumWidth(),
1186                            TI.getUnsignedAccumScale(), /*Signed=*/false);
1187     DefineFixedPointMacros(TI, Builder, "LACCUM", "LK", TI.getLongAccumWidth(),
1188                            TI.getLongAccumScale(), /*Signed=*/true);
1189     DefineFixedPointMacros(TI, Builder, "ULACCUM", "ULK",
1190                            TI.getLongAccumWidth(),
1191                            TI.getUnsignedLongAccumScale(), /*Signed=*/false);
1192 
1193     Builder.defineMacro("__SACCUM_IBIT__", Twine(TI.getShortAccumIBits()));
1194     Builder.defineMacro("__USACCUM_IBIT__",
1195                         Twine(TI.getUnsignedShortAccumIBits()));
1196     Builder.defineMacro("__ACCUM_IBIT__", Twine(TI.getAccumIBits()));
1197     Builder.defineMacro("__UACCUM_IBIT__", Twine(TI.getUnsignedAccumIBits()));
1198     Builder.defineMacro("__LACCUM_IBIT__", Twine(TI.getLongAccumIBits()));
1199     Builder.defineMacro("__ULACCUM_IBIT__",
1200                         Twine(TI.getUnsignedLongAccumIBits()));
1201   }
1202 
1203   if (TI.hasFloat16Type())
1204     DefineFloatMacros(Builder, "FLT16", &TI.getHalfFormat(), "F16");
1205   DefineFloatMacros(Builder, "FLT", &TI.getFloatFormat(), "F");
1206   DefineFloatMacros(Builder, "DBL", &TI.getDoubleFormat(), "");
1207   DefineFloatMacros(Builder, "LDBL", &TI.getLongDoubleFormat(), "L");
1208 
1209   // Define a __POINTER_WIDTH__ macro for stdint.h.
1210   Builder.defineMacro("__POINTER_WIDTH__",
1211                       Twine((int)TI.getPointerWidth(LangAS::Default)));
1212 
1213   // Define __BIGGEST_ALIGNMENT__ to be compatible with gcc.
1214   Builder.defineMacro("__BIGGEST_ALIGNMENT__",
1215                       Twine(TI.getSuitableAlign() / TI.getCharWidth()) );
1216 
1217   if (!LangOpts.CharIsSigned)
1218     Builder.defineMacro("__CHAR_UNSIGNED__");
1219 
1220   if (!TargetInfo::isTypeSigned(TI.getWCharType()))
1221     Builder.defineMacro("__WCHAR_UNSIGNED__");
1222 
1223   if (!TargetInfo::isTypeSigned(TI.getWIntType()))
1224     Builder.defineMacro("__WINT_UNSIGNED__");
1225 
1226   // Define exact-width integer types for stdint.h
1227   DefineExactWidthIntType(LangOpts, TargetInfo::SignedChar, TI, Builder);
1228 
1229   if (TI.getShortWidth() > TI.getCharWidth())
1230     DefineExactWidthIntType(LangOpts, TargetInfo::SignedShort, TI, Builder);
1231 
1232   if (TI.getIntWidth() > TI.getShortWidth())
1233     DefineExactWidthIntType(LangOpts, TargetInfo::SignedInt, TI, Builder);
1234 
1235   if (TI.getLongWidth() > TI.getIntWidth())
1236     DefineExactWidthIntType(LangOpts, TargetInfo::SignedLong, TI, Builder);
1237 
1238   if (TI.getLongLongWidth() > TI.getLongWidth())
1239     DefineExactWidthIntType(LangOpts, TargetInfo::SignedLongLong, TI, Builder);
1240 
1241   DefineExactWidthIntType(LangOpts, TargetInfo::UnsignedChar, TI, Builder);
1242   DefineExactWidthIntTypeSize(TargetInfo::UnsignedChar, TI, Builder);
1243   DefineExactWidthIntTypeSize(TargetInfo::SignedChar, TI, Builder);
1244 
1245   if (TI.getShortWidth() > TI.getCharWidth()) {
1246     DefineExactWidthIntType(LangOpts, TargetInfo::UnsignedShort, TI, Builder);
1247     DefineExactWidthIntTypeSize(TargetInfo::UnsignedShort, TI, Builder);
1248     DefineExactWidthIntTypeSize(TargetInfo::SignedShort, TI, Builder);
1249   }
1250 
1251   if (TI.getIntWidth() > TI.getShortWidth()) {
1252     DefineExactWidthIntType(LangOpts, TargetInfo::UnsignedInt, TI, Builder);
1253     DefineExactWidthIntTypeSize(TargetInfo::UnsignedInt, TI, Builder);
1254     DefineExactWidthIntTypeSize(TargetInfo::SignedInt, TI, Builder);
1255   }
1256 
1257   if (TI.getLongWidth() > TI.getIntWidth()) {
1258     DefineExactWidthIntType(LangOpts, TargetInfo::UnsignedLong, TI, Builder);
1259     DefineExactWidthIntTypeSize(TargetInfo::UnsignedLong, TI, Builder);
1260     DefineExactWidthIntTypeSize(TargetInfo::SignedLong, TI, Builder);
1261   }
1262 
1263   if (TI.getLongLongWidth() > TI.getLongWidth()) {
1264     DefineExactWidthIntType(LangOpts, TargetInfo::UnsignedLongLong, TI,
1265                             Builder);
1266     DefineExactWidthIntTypeSize(TargetInfo::UnsignedLongLong, TI, Builder);
1267     DefineExactWidthIntTypeSize(TargetInfo::SignedLongLong, TI, Builder);
1268   }
1269 
1270   DefineLeastWidthIntType(LangOpts, 8, true, TI, Builder);
1271   DefineLeastWidthIntType(LangOpts, 8, false, TI, Builder);
1272   DefineLeastWidthIntType(LangOpts, 16, true, TI, Builder);
1273   DefineLeastWidthIntType(LangOpts, 16, false, TI, Builder);
1274   DefineLeastWidthIntType(LangOpts, 32, true, TI, Builder);
1275   DefineLeastWidthIntType(LangOpts, 32, false, TI, Builder);
1276   DefineLeastWidthIntType(LangOpts, 64, true, TI, Builder);
1277   DefineLeastWidthIntType(LangOpts, 64, false, TI, Builder);
1278 
1279   DefineFastIntType(LangOpts, 8, true, TI, Builder);
1280   DefineFastIntType(LangOpts, 8, false, TI, Builder);
1281   DefineFastIntType(LangOpts, 16, true, TI, Builder);
1282   DefineFastIntType(LangOpts, 16, false, TI, Builder);
1283   DefineFastIntType(LangOpts, 32, true, TI, Builder);
1284   DefineFastIntType(LangOpts, 32, false, TI, Builder);
1285   DefineFastIntType(LangOpts, 64, true, TI, Builder);
1286   DefineFastIntType(LangOpts, 64, false, TI, Builder);
1287 
1288   Builder.defineMacro("__USER_LABEL_PREFIX__", TI.getUserLabelPrefix());
1289 
1290   if (!LangOpts.MathErrno)
1291     Builder.defineMacro("__NO_MATH_ERRNO__");
1292 
1293   if (LangOpts.FastMath || LangOpts.FiniteMathOnly)
1294     Builder.defineMacro("__FINITE_MATH_ONLY__", "1");
1295   else
1296     Builder.defineMacro("__FINITE_MATH_ONLY__", "0");
1297 
1298   if (LangOpts.GNUCVersion) {
1299     if (LangOpts.GNUInline || LangOpts.CPlusPlus)
1300       Builder.defineMacro("__GNUC_GNU_INLINE__");
1301     else
1302       Builder.defineMacro("__GNUC_STDC_INLINE__");
1303 
1304     // The value written by __atomic_test_and_set.
1305     // FIXME: This is target-dependent.
1306     Builder.defineMacro("__GCC_ATOMIC_TEST_AND_SET_TRUEVAL", "1");
1307   }
1308 
1309   auto addLockFreeMacros = [&](const llvm::Twine &Prefix) {
1310     // Used by libc++ and libstdc++ to implement ATOMIC_<foo>_LOCK_FREE.
1311 #define DEFINE_LOCK_FREE_MACRO(TYPE, Type)                                     \
1312   Builder.defineMacro(Prefix + #TYPE "_LOCK_FREE",                             \
1313                       getLockFreeValue(TI.get##Type##Width(), TI));
1314     DEFINE_LOCK_FREE_MACRO(BOOL, Bool);
1315     DEFINE_LOCK_FREE_MACRO(CHAR, Char);
1316     if (LangOpts.Char8)
1317       DEFINE_LOCK_FREE_MACRO(CHAR8_T, Char); // Treat char8_t like char.
1318     DEFINE_LOCK_FREE_MACRO(CHAR16_T, Char16);
1319     DEFINE_LOCK_FREE_MACRO(CHAR32_T, Char32);
1320     DEFINE_LOCK_FREE_MACRO(WCHAR_T, WChar);
1321     DEFINE_LOCK_FREE_MACRO(SHORT, Short);
1322     DEFINE_LOCK_FREE_MACRO(INT, Int);
1323     DEFINE_LOCK_FREE_MACRO(LONG, Long);
1324     DEFINE_LOCK_FREE_MACRO(LLONG, LongLong);
1325     Builder.defineMacro(
1326         Prefix + "POINTER_LOCK_FREE",
1327         getLockFreeValue(TI.getPointerWidth(LangAS::Default), TI));
1328 #undef DEFINE_LOCK_FREE_MACRO
1329   };
1330   addLockFreeMacros("__CLANG_ATOMIC_");
1331   if (LangOpts.GNUCVersion)
1332     addLockFreeMacros("__GCC_ATOMIC_");
1333 
1334   if (LangOpts.NoInlineDefine)
1335     Builder.defineMacro("__NO_INLINE__");
1336 
1337   if (unsigned PICLevel = LangOpts.PICLevel) {
1338     Builder.defineMacro("__PIC__", Twine(PICLevel));
1339     Builder.defineMacro("__pic__", Twine(PICLevel));
1340     if (LangOpts.PIE) {
1341       Builder.defineMacro("__PIE__", Twine(PICLevel));
1342       Builder.defineMacro("__pie__", Twine(PICLevel));
1343     }
1344   }
1345 
1346   // Macros to control C99 numerics and <float.h>
1347   Builder.defineMacro("__FLT_RADIX__", "2");
1348   Builder.defineMacro("__DECIMAL_DIG__", "__LDBL_DECIMAL_DIG__");
1349 
1350   if (LangOpts.getStackProtector() == LangOptions::SSPOn)
1351     Builder.defineMacro("__SSP__");
1352   else if (LangOpts.getStackProtector() == LangOptions::SSPStrong)
1353     Builder.defineMacro("__SSP_STRONG__", "2");
1354   else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
1355     Builder.defineMacro("__SSP_ALL__", "3");
1356 
1357   if (PPOpts.SetUpStaticAnalyzer)
1358     Builder.defineMacro("__clang_analyzer__");
1359 
1360   if (LangOpts.FastRelaxedMath)
1361     Builder.defineMacro("__FAST_RELAXED_MATH__");
1362 
1363   if (FEOpts.ProgramAction == frontend::RewriteObjC ||
1364       LangOpts.getGC() != LangOptions::NonGC) {
1365     Builder.defineMacro("__weak", "__attribute__((objc_gc(weak)))");
1366     Builder.defineMacro("__strong", "__attribute__((objc_gc(strong)))");
1367     Builder.defineMacro("__autoreleasing", "");
1368     Builder.defineMacro("__unsafe_unretained", "");
1369   } else if (LangOpts.ObjC) {
1370     Builder.defineMacro("__weak", "__attribute__((objc_ownership(weak)))");
1371     Builder.defineMacro("__strong", "__attribute__((objc_ownership(strong)))");
1372     Builder.defineMacro("__autoreleasing",
1373                         "__attribute__((objc_ownership(autoreleasing)))");
1374     Builder.defineMacro("__unsafe_unretained",
1375                         "__attribute__((objc_ownership(none)))");
1376   }
1377 
1378   // On Darwin, there are __double_underscored variants of the type
1379   // nullability qualifiers.
1380   if (TI.getTriple().isOSDarwin()) {
1381     Builder.defineMacro("__nonnull", "_Nonnull");
1382     Builder.defineMacro("__null_unspecified", "_Null_unspecified");
1383     Builder.defineMacro("__nullable", "_Nullable");
1384   }
1385 
1386   // Add a macro to differentiate between regular iOS/tvOS/watchOS targets and
1387   // the corresponding simulator targets.
1388   if (TI.getTriple().isOSDarwin() && TI.getTriple().isSimulatorEnvironment())
1389     Builder.defineMacro("__APPLE_EMBEDDED_SIMULATOR__", "1");
1390 
1391   // OpenMP definition
1392   // OpenMP 2.2:
1393   //   In implementations that support a preprocessor, the _OPENMP
1394   //   macro name is defined to have the decimal value yyyymm where
1395   //   yyyy and mm are the year and the month designations of the
1396   //   version of the OpenMP API that the implementation support.
1397   if (!LangOpts.OpenMPSimd) {
1398     switch (LangOpts.OpenMP) {
1399     case 0:
1400       break;
1401     case 31:
1402       Builder.defineMacro("_OPENMP", "201107");
1403       break;
1404     case 40:
1405       Builder.defineMacro("_OPENMP", "201307");
1406       break;
1407     case 45:
1408       Builder.defineMacro("_OPENMP", "201511");
1409       break;
1410     case 50:
1411       Builder.defineMacro("_OPENMP", "201811");
1412       break;
1413     case 52:
1414       Builder.defineMacro("_OPENMP", "202111");
1415       break;
1416     default: // case 51:
1417       // Default version is OpenMP 5.1
1418       Builder.defineMacro("_OPENMP", "202011");
1419       break;
1420     }
1421   }
1422 
1423   // CUDA device path compilaton
1424   if (LangOpts.CUDAIsDevice && !LangOpts.HIP) {
1425     // The CUDA_ARCH value is set for the GPU target specified in the NVPTX
1426     // backend's target defines.
1427     Builder.defineMacro("__CUDA_ARCH__");
1428   }
1429 
1430   // We need to communicate this to our CUDA/HIP header wrapper, which in turn
1431   // informs the proper CUDA/HIP headers of this choice.
1432   if (LangOpts.GPUDeviceApproxTranscendentals)
1433     Builder.defineMacro("__CLANG_GPU_APPROX_TRANSCENDENTALS__");
1434 
1435   // Define a macro indicating that the source file is being compiled with a
1436   // SYCL device compiler which doesn't produce host binary.
1437   if (LangOpts.SYCLIsDevice) {
1438     Builder.defineMacro("__SYCL_DEVICE_ONLY__", "1");
1439   }
1440 
1441   // OpenCL definitions.
1442   if (LangOpts.OpenCL) {
1443     InitializeOpenCLFeatureTestMacros(TI, LangOpts, Builder);
1444 
1445     if (TI.getTriple().isSPIR() || TI.getTriple().isSPIRV())
1446       Builder.defineMacro("__IMAGE_SUPPORT__");
1447   }
1448 
1449   if (TI.hasInt128Type() && LangOpts.CPlusPlus && LangOpts.GNUMode) {
1450     // For each extended integer type, g++ defines a macro mapping the
1451     // index of the type (0 in this case) in some list of extended types
1452     // to the type.
1453     Builder.defineMacro("__GLIBCXX_TYPE_INT_N_0", "__int128");
1454     Builder.defineMacro("__GLIBCXX_BITSIZE_INT_N_0", "128");
1455   }
1456 
1457   // ELF targets define __ELF__
1458   if (TI.getTriple().isOSBinFormatELF())
1459     Builder.defineMacro("__ELF__");
1460 
1461   // Target OS macro definitions.
1462   if (PPOpts.DefineTargetOSMacros) {
1463     const llvm::Triple &Triple = TI.getTriple();
1464 #define TARGET_OS(Name, Predicate)                                             \
1465   Builder.defineMacro(#Name, (Predicate) ? "1" : "0");
1466 #include "clang/Basic/TargetOSMacros.def"
1467 #undef TARGET_OS
1468   }
1469 
1470   // Get other target #defines.
1471   TI.getTargetDefines(LangOpts, Builder);
1472 }
1473 
1474 static void InitializePGOProfileMacros(const CodeGenOptions &CodeGenOpts,
1475                                        MacroBuilder &Builder) {
1476   if (CodeGenOpts.hasProfileInstr())
1477     Builder.defineMacro("__LLVM_INSTR_PROFILE_GENERATE");
1478 
1479   if (CodeGenOpts.hasProfileIRUse() || CodeGenOpts.hasProfileClangUse())
1480     Builder.defineMacro("__LLVM_INSTR_PROFILE_USE");
1481 }
1482 
1483 /// InitializePreprocessor - Initialize the preprocessor getting it and the
1484 /// environment ready to process a single file.
1485 void clang::InitializePreprocessor(Preprocessor &PP,
1486                                    const PreprocessorOptions &InitOpts,
1487                                    const PCHContainerReader &PCHContainerRdr,
1488                                    const FrontendOptions &FEOpts,
1489                                    const CodeGenOptions &CodeGenOpts) {
1490   const LangOptions &LangOpts = PP.getLangOpts();
1491   std::string PredefineBuffer;
1492   PredefineBuffer.reserve(4080);
1493   llvm::raw_string_ostream Predefines(PredefineBuffer);
1494   MacroBuilder Builder(Predefines);
1495 
1496   // Emit line markers for various builtin sections of the file. The 3 here
1497   // marks <built-in> as being a system header, which suppresses warnings when
1498   // the same macro is defined multiple times.
1499   Builder.append("# 1 \"<built-in>\" 3");
1500 
1501   // Install things like __POWERPC__, __GNUC__, etc into the macro table.
1502   if (InitOpts.UsePredefines) {
1503     // FIXME: This will create multiple definitions for most of the predefined
1504     // macros. This is not the right way to handle this.
1505     if ((LangOpts.CUDA || LangOpts.OpenMPIsTargetDevice ||
1506          LangOpts.SYCLIsDevice) &&
1507         PP.getAuxTargetInfo())
1508       InitializePredefinedMacros(*PP.getAuxTargetInfo(), LangOpts, FEOpts,
1509                                  PP.getPreprocessorOpts(), Builder);
1510 
1511     InitializePredefinedMacros(PP.getTargetInfo(), LangOpts, FEOpts,
1512                                PP.getPreprocessorOpts(), Builder);
1513 
1514     // Install definitions to make Objective-C++ ARC work well with various
1515     // C++ Standard Library implementations.
1516     if (LangOpts.ObjC && LangOpts.CPlusPlus &&
1517         (LangOpts.ObjCAutoRefCount || LangOpts.ObjCWeak)) {
1518       switch (InitOpts.ObjCXXARCStandardLibrary) {
1519       case ARCXX_nolib:
1520       case ARCXX_libcxx:
1521         break;
1522 
1523       case ARCXX_libstdcxx:
1524         AddObjCXXARCLibstdcxxDefines(LangOpts, Builder);
1525         break;
1526       }
1527     }
1528   }
1529 
1530   // Even with predefines off, some macros are still predefined.
1531   // These should all be defined in the preprocessor according to the
1532   // current language configuration.
1533   InitializeStandardPredefinedMacros(PP.getTargetInfo(), PP.getLangOpts(),
1534                                      FEOpts, Builder);
1535 
1536   // The PGO instrumentation profile macros are driven by options
1537   // -fprofile[-instr]-generate/-fcs-profile-generate/-fprofile[-instr]-use,
1538   // hence they are not guarded by InitOpts.UsePredefines.
1539   InitializePGOProfileMacros(CodeGenOpts, Builder);
1540 
1541   // Add on the predefines from the driver.  Wrap in a #line directive to report
1542   // that they come from the command line.
1543   Builder.append("# 1 \"<command line>\" 1");
1544 
1545   // Process #define's and #undef's in the order they are given.
1546   for (unsigned i = 0, e = InitOpts.Macros.size(); i != e; ++i) {
1547     if (InitOpts.Macros[i].second)  // isUndef
1548       Builder.undefineMacro(InitOpts.Macros[i].first);
1549     else
1550       DefineBuiltinMacro(Builder, InitOpts.Macros[i].first,
1551                          PP.getDiagnostics());
1552   }
1553 
1554   // Exit the command line and go back to <built-in> (2 is LC_LEAVE).
1555   Builder.append("# 1 \"<built-in>\" 2");
1556 
1557   // If -imacros are specified, include them now.  These are processed before
1558   // any -include directives.
1559   for (unsigned i = 0, e = InitOpts.MacroIncludes.size(); i != e; ++i)
1560     AddImplicitIncludeMacros(Builder, InitOpts.MacroIncludes[i]);
1561 
1562   // Process -include-pch/-include-pth directives.
1563   if (!InitOpts.ImplicitPCHInclude.empty())
1564     AddImplicitIncludePCH(Builder, PP, PCHContainerRdr,
1565                           InitOpts.ImplicitPCHInclude);
1566 
1567   // Process -include directives.
1568   for (unsigned i = 0, e = InitOpts.Includes.size(); i != e; ++i) {
1569     const std::string &Path = InitOpts.Includes[i];
1570     AddImplicitInclude(Builder, Path);
1571   }
1572 
1573   // Instruct the preprocessor to skip the preamble.
1574   PP.setSkipMainFilePreamble(InitOpts.PrecompiledPreambleBytes.first,
1575                              InitOpts.PrecompiledPreambleBytes.second);
1576 
1577   // Copy PredefinedBuffer into the Preprocessor.
1578   PP.setPredefines(std::move(PredefineBuffer));
1579 }
1580