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   if (Triple.isOSDarwin()) {
112     // Any darwin OS defines a general darwin OS version macro in addition
113     // to the other OS specific macros.
114     assert(OsVersion.getMinor().value_or(0) < 100 &&
115            OsVersion.getSubminor().value_or(0) < 100 && "Invalid version!");
116     Builder.defineMacro("__ENVIRONMENT_OS_VERSION_MIN_REQUIRED__", Str);
117 
118     // Tell users about the kernel if there is one.
119     Builder.defineMacro("__MACH__");
120   }
121 
122   PlatformMinVersion = OsVersion;
123 }
124 
125 static void addMinGWDefines(const llvm::Triple &Triple, const LangOptions &Opts,
126                             MacroBuilder &Builder) {
127   DefineStd(Builder, "WIN32", Opts);
128   DefineStd(Builder, "WINNT", Opts);
129   if (Triple.isArch64Bit()) {
130     DefineStd(Builder, "WIN64", Opts);
131     Builder.defineMacro("__MINGW64__");
132   }
133   Builder.defineMacro("__MSVCRT__");
134   Builder.defineMacro("__MINGW32__");
135   addCygMingDefines(Opts, Builder);
136 }
137 
138 static void addVisualCDefines(const LangOptions &Opts, MacroBuilder &Builder) {
139   if (Opts.CPlusPlus) {
140     if (Opts.RTTIData)
141       Builder.defineMacro("_CPPRTTI");
142 
143     if (Opts.CXXExceptions)
144       Builder.defineMacro("_CPPUNWIND");
145   }
146 
147   if (Opts.Bool)
148     Builder.defineMacro("__BOOL_DEFINED");
149 
150   if (!Opts.CharIsSigned)
151     Builder.defineMacro("_CHAR_UNSIGNED");
152 
153   // "The /fp:contract option allows the compiler to generate floating-point
154   // contractions [...]"
155   if (Opts.getDefaultFPContractMode() != LangOptions::FPModeKind::FPM_Off)
156     Builder.defineMacro("_M_FP_CONTRACT");
157 
158   // "The /fp:except option generates code to ensures that any unmasked
159   // floating-point exceptions are raised at the exact point at which they
160   // occur, and that no other floating-point exceptions are raised."
161   if (Opts.getDefaultExceptionMode() ==
162       LangOptions::FPExceptionModeKind::FPE_Strict)
163     Builder.defineMacro("_M_FP_EXCEPT");
164 
165   // "The /fp:fast option allows the compiler to reorder, combine, or simplify
166   // floating-point operations to optimize floating-point code for speed and
167   // space. The compiler may omit rounding at assignment statements,
168   // typecasts, or function calls. It may reorder operations or make algebraic
169   // transforms, for example, by use of associative and distributive laws. It
170   // may reorder code even if such transformations result in observably
171   // different rounding behavior."
172   //
173   // "Under /fp:precise and /fp:strict, the compiler doesn't do any mathematical
174   // transformation unless the transformation is guaranteed to produce a bitwise
175   // identical result."
176   const bool any_imprecise_flags =
177       Opts.FastMath || Opts.FiniteMathOnly || Opts.UnsafeFPMath ||
178       Opts.AllowFPReassoc || Opts.NoHonorNaNs || Opts.NoHonorInfs ||
179       Opts.NoSignedZero || Opts.AllowRecip || Opts.ApproxFunc;
180 
181   // "Under both /fp:precise and /fp:fast, the compiler generates code intended
182   // to run in the default floating-point environment."
183   //
184   // "[The] default floating point environment [...] sets the rounding mode
185   // to round to nearest."
186   if (Opts.getDefaultRoundingMode() ==
187       LangOptions::RoundingMode::NearestTiesToEven) {
188     if (any_imprecise_flags) {
189       Builder.defineMacro("_M_FP_FAST");
190     } else {
191       Builder.defineMacro("_M_FP_PRECISE");
192     }
193   } else if (!any_imprecise_flags && Opts.getDefaultRoundingMode() ==
194                                          LangOptions::RoundingMode::Dynamic) {
195     // "Under /fp:strict, the compiler generates code that allows the
196     // program to safely unmask floating-point exceptions, read or write
197     // floating-point status registers, or change rounding modes."
198     Builder.defineMacro("_M_FP_STRICT");
199   }
200 
201   // FIXME: POSIXThreads isn't exactly the option this should be defined for,
202   //        but it works for now.
203   if (Opts.POSIXThreads)
204     Builder.defineMacro("_MT");
205 
206   if (Opts.MSCompatibilityVersion) {
207     Builder.defineMacro("_MSC_VER",
208                         Twine(Opts.MSCompatibilityVersion / 100000));
209     Builder.defineMacro("_MSC_FULL_VER", Twine(Opts.MSCompatibilityVersion));
210     // FIXME We cannot encode the revision information into 32-bits
211     Builder.defineMacro("_MSC_BUILD", Twine(1));
212 
213     if (Opts.CPlusPlus11 && Opts.isCompatibleWithMSVC(LangOptions::MSVC2015))
214       Builder.defineMacro("_HAS_CHAR16_T_LANGUAGE_SUPPORT", Twine(1));
215 
216     if (Opts.isCompatibleWithMSVC(LangOptions::MSVC2015)) {
217       if (Opts.CPlusPlus23)
218         // TODO update to the proper value.
219         Builder.defineMacro("_MSVC_LANG", "202004L");
220       else if (Opts.CPlusPlus20)
221         Builder.defineMacro("_MSVC_LANG", "202002L");
222       else if (Opts.CPlusPlus17)
223         Builder.defineMacro("_MSVC_LANG", "201703L");
224       else if (Opts.CPlusPlus14)
225         Builder.defineMacro("_MSVC_LANG", "201402L");
226     }
227   }
228 
229   if (Opts.MicrosoftExt) {
230     Builder.defineMacro("_MSC_EXTENSIONS");
231 
232     if (Opts.CPlusPlus11) {
233       Builder.defineMacro("_RVALUE_REFERENCES_V2_SUPPORTED");
234       Builder.defineMacro("_RVALUE_REFERENCES_SUPPORTED");
235       Builder.defineMacro("_NATIVE_NULLPTR_SUPPORTED");
236     }
237   }
238 
239   if (!Opts.MSVolatile)
240     Builder.defineMacro("_ISO_VOLATILE");
241 
242   if (Opts.Kernel)
243     Builder.defineMacro("_KERNEL_MODE");
244 
245   Builder.defineMacro("_INTEGRAL_MAX_BITS", "64");
246   Builder.defineMacro("__STDC_NO_THREADS__");
247 
248   // Starting with VS 2022 17.1, MSVC predefines the below macro to inform
249   // users of the execution character set defined at compile time.
250   // The value given is the Windows Code Page Identifier:
251   // https://docs.microsoft.com/en-us/windows/win32/intl/code-page-identifiers
252   //
253   // Clang currently only supports UTF-8, so we'll use 65001
254   Builder.defineMacro("_MSVC_EXECUTION_CHARACTER_SET", "65001");
255 }
256 
257 void addWindowsDefines(const llvm::Triple &Triple, const LangOptions &Opts,
258                        MacroBuilder &Builder) {
259   Builder.defineMacro("_WIN32");
260   if (Triple.isArch64Bit())
261     Builder.defineMacro("_WIN64");
262   if (Triple.isWindowsGNUEnvironment())
263     addMinGWDefines(Triple, Opts, Builder);
264   else if (Triple.isKnownWindowsMSVCEnvironment() ||
265            (Triple.isWindowsItaniumEnvironment() && Opts.MSVCCompat))
266     addVisualCDefines(Opts, Builder);
267 }
268 
269 } // namespace targets
270 } // namespace clang
271