1 //===--- OSTargets.cpp - Implement OS target feature support --------------===//
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 OS specific TargetInfo types.
10 //===----------------------------------------------------------------------===//
11 
12 #include "OSTargets.h"
13 #include "clang/Basic/MacroBuilder.h"
14 #include "llvm/ADT/StringRef.h"
15 
16 using namespace clang;
17 using namespace clang::targets;
18 
19 namespace clang {
20 namespace targets {
21 
22 void getDarwinDefines(MacroBuilder &Builder, const LangOptions &Opts,
23                       const llvm::Triple &Triple, StringRef &PlatformName,
24                       VersionTuple &PlatformMinVersion) {
25   Builder.defineMacro("__APPLE_CC__", "6000");
26   Builder.defineMacro("__APPLE__");
27   Builder.defineMacro("__STDC_NO_THREADS__");
28 
29   // AddressSanitizer doesn't play well with source fortification, which is on
30   // by default on Darwin.
31   if (Opts.Sanitize.has(SanitizerKind::Address))
32     Builder.defineMacro("_FORTIFY_SOURCE", "0");
33 
34   // Darwin defines __weak, __strong, and __unsafe_unretained even in C mode.
35   if (!Opts.ObjC) {
36     // __weak is always defined, for use in blocks and with objc pointers.
37     Builder.defineMacro("__weak", "__attribute__((objc_gc(weak)))");
38     Builder.defineMacro("__strong", "");
39     Builder.defineMacro("__unsafe_unretained", "");
40   }
41 
42   if (Opts.Static)
43     Builder.defineMacro("__STATIC__");
44   else
45     Builder.defineMacro("__DYNAMIC__");
46 
47   if (Opts.POSIXThreads)
48     Builder.defineMacro("_REENTRANT");
49 
50   // Get the platform type and version number from the triple.
51   VersionTuple OsVersion;
52   if (Triple.isMacOSX()) {
53     Triple.getMacOSXVersion(OsVersion);
54     PlatformName = "macos";
55   } else {
56     OsVersion = Triple.getOSVersion();
57     PlatformName = llvm::Triple::getOSTypeName(Triple.getOS());
58     if (PlatformName == "ios" && Triple.isMacCatalystEnvironment())
59       PlatformName = "maccatalyst";
60   }
61 
62   // If -target arch-pc-win32-macho option specified, we're
63   // generating code for Win32 ABI. No need to emit
64   // __ENVIRONMENT_XX_OS_VERSION_MIN_REQUIRED__.
65   if (PlatformName == "win32") {
66     PlatformMinVersion = OsVersion;
67     return;
68   }
69 
70   assert(OsVersion < VersionTuple(100) && "Invalid version!");
71   char Str[7];
72   if (Triple.isMacOSX() && OsVersion < VersionTuple(10, 10)) {
73     Str[0] = '0' + (OsVersion.getMajor() / 10);
74     Str[1] = '0' + (OsVersion.getMajor() % 10);
75     Str[2] = '0' + std::min(OsVersion.getMinor().value_or(0), 9U);
76     Str[3] = '0' + std::min(OsVersion.getSubminor().value_or(0), 9U);
77     Str[4] = '\0';
78   } else if (!Triple.isMacOSX() && OsVersion.getMajor() < 10) {
79     Str[0] = '0' + OsVersion.getMajor();
80     Str[1] = '0' + (OsVersion.getMinor().value_or(0) / 10);
81     Str[2] = '0' + (OsVersion.getMinor().value_or(0) % 10);
82     Str[3] = '0' + (OsVersion.getSubminor().value_or(0) / 10);
83     Str[4] = '0' + (OsVersion.getSubminor().value_or(0) % 10);
84     Str[5] = '\0';
85   } else {
86     // Handle versions >= 10.
87     Str[0] = '0' + (OsVersion.getMajor() / 10);
88     Str[1] = '0' + (OsVersion.getMajor() % 10);
89     Str[2] = '0' + (OsVersion.getMinor().value_or(0) / 10);
90     Str[3] = '0' + (OsVersion.getMinor().value_or(0) % 10);
91     Str[4] = '0' + (OsVersion.getSubminor().value_or(0) / 10);
92     Str[5] = '0' + (OsVersion.getSubminor().value_or(0) % 10);
93     Str[6] = '\0';
94   }
95 
96   // Set the appropriate OS version define.
97   if (Triple.isTvOS()) {
98     Builder.defineMacro("__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__", Str);
99   } else if (Triple.isiOS()) {
100     Builder.defineMacro("__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__", Str);
101   } else if (Triple.isWatchOS()) {
102     Builder.defineMacro("__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__", Str);
103   } else if (Triple.isDriverKit()) {
104     assert(OsVersion.getMinor().value_or(0) < 100 &&
105            OsVersion.getSubminor().value_or(0) < 100 && "Invalid version!");
106     Builder.defineMacro("__ENVIRONMENT_DRIVERKIT_VERSION_MIN_REQUIRED__", Str);
107   } else if (Triple.isMacOSX()) {
108     Builder.defineMacro("__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__", Str);
109   }
110 
111   // Tell users about the kernel if there is one.
112   if (Triple.isOSDarwin())
113     Builder.defineMacro("__MACH__");
114 
115   PlatformMinVersion = OsVersion;
116 }
117 
118 static void addMinGWDefines(const llvm::Triple &Triple, const LangOptions &Opts,
119                             MacroBuilder &Builder) {
120   DefineStd(Builder, "WIN32", Opts);
121   DefineStd(Builder, "WINNT", Opts);
122   if (Triple.isArch64Bit()) {
123     DefineStd(Builder, "WIN64", Opts);
124     Builder.defineMacro("__MINGW64__");
125   }
126   Builder.defineMacro("__MSVCRT__");
127   Builder.defineMacro("__MINGW32__");
128   addCygMingDefines(Opts, Builder);
129 }
130 
131 static void addVisualCDefines(const LangOptions &Opts, MacroBuilder &Builder) {
132   if (Opts.CPlusPlus) {
133     if (Opts.RTTIData)
134       Builder.defineMacro("_CPPRTTI");
135 
136     if (Opts.CXXExceptions)
137       Builder.defineMacro("_CPPUNWIND");
138   }
139 
140   if (Opts.Bool)
141     Builder.defineMacro("__BOOL_DEFINED");
142 
143   if (!Opts.CharIsSigned)
144     Builder.defineMacro("_CHAR_UNSIGNED");
145 
146   // "The /fp:contract option allows the compiler to generate floating-point
147   // contractions [...]"
148   if (Opts.getDefaultFPContractMode() != LangOptions::FPModeKind::FPM_Off)
149     Builder.defineMacro("_M_FP_CONTRACT");
150 
151   // "The /fp:except option generates code to ensures that any unmasked
152   // floating-point exceptions are raised at the exact point at which they
153   // occur, and that no other floating-point exceptions are raised."
154   if (Opts.getDefaultExceptionMode() ==
155       LangOptions::FPExceptionModeKind::FPE_Strict)
156     Builder.defineMacro("_M_FP_EXCEPT");
157 
158   // "The /fp:fast option allows the compiler to reorder, combine, or simplify
159   // floating-point operations to optimize floating-point code for speed and
160   // space. The compiler may omit rounding at assignment statements,
161   // typecasts, or function calls. It may reorder operations or make algebraic
162   // transforms, for example, by use of associative and distributive laws. It
163   // may reorder code even if such transformations result in observably
164   // different rounding behavior."
165   //
166   // "Under /fp:precise and /fp:strict, the compiler doesn't do any mathematical
167   // transformation unless the transformation is guaranteed to produce a bitwise
168   // identical result."
169   const bool any_imprecise_flags =
170       Opts.FastMath || Opts.FiniteMathOnly || Opts.UnsafeFPMath ||
171       Opts.AllowFPReassoc || Opts.NoHonorNaNs || Opts.NoHonorInfs ||
172       Opts.NoSignedZero || Opts.AllowRecip || Opts.ApproxFunc;
173 
174   // "Under both /fp:precise and /fp:fast, the compiler generates code intended
175   // to run in the default floating-point environment."
176   //
177   // "[The] default floating point environment [...] sets the rounding mode
178   // to round to nearest."
179   if (Opts.getDefaultRoundingMode() ==
180       LangOptions::RoundingMode::NearestTiesToEven) {
181     if (any_imprecise_flags) {
182       Builder.defineMacro("_M_FP_FAST");
183     } else {
184       Builder.defineMacro("_M_FP_PRECISE");
185     }
186   } else if (!any_imprecise_flags && Opts.getDefaultRoundingMode() ==
187                                          LangOptions::RoundingMode::Dynamic) {
188     // "Under /fp:strict, the compiler generates code that allows the
189     // program to safely unmask floating-point exceptions, read or write
190     // floating-point status registers, or change rounding modes."
191     Builder.defineMacro("_M_FP_STRICT");
192   }
193 
194   // FIXME: POSIXThreads isn't exactly the option this should be defined for,
195   //        but it works for now.
196   if (Opts.POSIXThreads)
197     Builder.defineMacro("_MT");
198 
199   if (Opts.MSCompatibilityVersion) {
200     Builder.defineMacro("_MSC_VER",
201                         Twine(Opts.MSCompatibilityVersion / 100000));
202     Builder.defineMacro("_MSC_FULL_VER", Twine(Opts.MSCompatibilityVersion));
203     // FIXME We cannot encode the revision information into 32-bits
204     Builder.defineMacro("_MSC_BUILD", Twine(1));
205 
206     if (Opts.CPlusPlus11 && Opts.isCompatibleWithMSVC(LangOptions::MSVC2015))
207       Builder.defineMacro("_HAS_CHAR16_T_LANGUAGE_SUPPORT", Twine(1));
208 
209     if (Opts.isCompatibleWithMSVC(LangOptions::MSVC2015)) {
210       if (Opts.CPlusPlus2b)
211         Builder.defineMacro("_MSVC_LANG", "202004L");
212       else if (Opts.CPlusPlus20)
213         Builder.defineMacro("_MSVC_LANG", "202002L");
214       else if (Opts.CPlusPlus17)
215         Builder.defineMacro("_MSVC_LANG", "201703L");
216       else if (Opts.CPlusPlus14)
217         Builder.defineMacro("_MSVC_LANG", "201402L");
218     }
219   }
220 
221   if (Opts.MicrosoftExt) {
222     Builder.defineMacro("_MSC_EXTENSIONS");
223 
224     if (Opts.CPlusPlus11) {
225       Builder.defineMacro("_RVALUE_REFERENCES_V2_SUPPORTED");
226       Builder.defineMacro("_RVALUE_REFERENCES_SUPPORTED");
227       Builder.defineMacro("_NATIVE_NULLPTR_SUPPORTED");
228     }
229   }
230 
231   if (!Opts.MSVolatile)
232     Builder.defineMacro("_ISO_VOLATILE");
233 
234   if (Opts.Kernel)
235     Builder.defineMacro("_KERNEL_MODE");
236 
237   Builder.defineMacro("_INTEGRAL_MAX_BITS", "64");
238   Builder.defineMacro("__STDC_NO_THREADS__");
239 
240   // Starting with VS 2022 17.1, MSVC predefines the below macro to inform
241   // users of the execution character set defined at compile time.
242   // The value given is the Windows Code Page Identifier:
243   // https://docs.microsoft.com/en-us/windows/win32/intl/code-page-identifiers
244   //
245   // Clang currently only supports UTF-8, so we'll use 65001
246   Builder.defineMacro("_MSVC_EXECUTION_CHARACTER_SET", "65001");
247 }
248 
249 void addWindowsDefines(const llvm::Triple &Triple, const LangOptions &Opts,
250                        MacroBuilder &Builder) {
251   Builder.defineMacro("_WIN32");
252   if (Triple.isArch64Bit())
253     Builder.defineMacro("_WIN64");
254   if (Triple.isWindowsGNUEnvironment())
255     addMinGWDefines(Triple, Opts, Builder);
256   else if (Triple.isKnownWindowsMSVCEnvironment() ||
257            (Triple.isWindowsItaniumEnvironment() && Opts.MSVCCompat))
258     addVisualCDefines(Opts, Builder);
259 }
260 
261 } // namespace targets
262 } // namespace clang
263