1 //===- LangOptions.cpp - C Language Family Language Options ---------------===//
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 defines the LangOptions class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/Basic/LangOptions.h"
14 #include "llvm/ADT/SmallString.h"
15 #include "llvm/Support/Path.h"
16 
17 using namespace clang;
18 
19 LangOptions::LangOptions() : LangStd(LangStandard::lang_unspecified) {
20 #define LANGOPT(Name, Bits, Default, Description) Name = Default;
21 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) set##Name(Default);
22 #include "clang/Basic/LangOptions.def"
23 }
24 
25 void LangOptions::resetNonModularOptions() {
26 #define LANGOPT(Name, Bits, Default, Description)
27 #define BENIGN_LANGOPT(Name, Bits, Default, Description) Name = Default;
28 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
29   Name = static_cast<unsigned>(Default);
30 #include "clang/Basic/LangOptions.def"
31 
32   // Reset "benign" options with implied values (Options.td ImpliedBy relations)
33   // rather than their defaults. This avoids unexpected combinations and
34   // invocations that cannot be round-tripped to arguments.
35   // FIXME: we should derive this automatically from ImpliedBy in tablegen.
36   AllowFPReassoc = UnsafeFPMath;
37   NoHonorNaNs = FiniteMathOnly;
38   NoHonorInfs = FiniteMathOnly;
39 
40   // These options do not affect AST generation.
41   NoSanitizeFiles.clear();
42   XRayAlwaysInstrumentFiles.clear();
43   XRayNeverInstrumentFiles.clear();
44 
45   CurrentModule.clear();
46   IsHeaderFile = false;
47 }
48 
49 bool LangOptions::isNoBuiltinFunc(StringRef FuncName) const {
50   for (unsigned i = 0, e = NoBuiltinFuncs.size(); i != e; ++i)
51     if (FuncName.equals(NoBuiltinFuncs[i]))
52       return true;
53   return false;
54 }
55 
56 VersionTuple LangOptions::getOpenCLVersionTuple() const {
57   const int Ver = OpenCLCPlusPlus ? OpenCLCPlusPlusVersion : OpenCLVersion;
58   if (OpenCLCPlusPlus && Ver != 100)
59     return VersionTuple(Ver / 100);
60   return VersionTuple(Ver / 100, (Ver % 100) / 10);
61 }
62 
63 unsigned LangOptions::getOpenCLCompatibleVersion() const {
64   if (!OpenCLCPlusPlus)
65     return OpenCLVersion;
66   if (OpenCLCPlusPlusVersion == 100)
67     return 200;
68   if (OpenCLCPlusPlusVersion == 202100)
69     return 300;
70   llvm_unreachable("Unknown OpenCL version");
71 }
72 
73 void LangOptions::remapPathPrefix(SmallVectorImpl<char> &Path) const {
74   for (const auto &Entry : MacroPrefixMap)
75     if (llvm::sys::path::replace_path_prefix(Path, Entry.first, Entry.second))
76       break;
77 }
78 
79 std::string LangOptions::getOpenCLVersionString() const {
80   std::string Result;
81   {
82     llvm::raw_string_ostream Out(Result);
83     Out << (OpenCLCPlusPlus ? "C++ for OpenCL" : "OpenCL C") << " version "
84         << getOpenCLVersionTuple().getAsString();
85   }
86   return Result;
87 }
88 
89 void LangOptions::setLangDefaults(LangOptions &Opts, Language Lang,
90                                   const llvm::Triple &T,
91                                   std::vector<std::string> &Includes,
92                                   LangStandard::Kind LangStd) {
93   // Set some properties which depend solely on the input kind; it would be nice
94   // to move these to the language standard, and have the driver resolve the
95   // input kind + language standard.
96   //
97   // FIXME: Perhaps a better model would be for a single source file to have
98   // multiple language standards (C / C++ std, ObjC std, OpenCL std, OpenMP std)
99   // simultaneously active?
100   if (Lang == Language::Asm) {
101     Opts.AsmPreprocessor = 1;
102   } else if (Lang == Language::ObjC || Lang == Language::ObjCXX) {
103     Opts.ObjC = 1;
104   }
105 
106   if (LangStd == LangStandard::lang_unspecified)
107     LangStd = getDefaultLanguageStandard(Lang, T);
108   const LangStandard &Std = LangStandard::getLangStandardForKind(LangStd);
109   Opts.LangStd = LangStd;
110   Opts.LineComment = Std.hasLineComments();
111   Opts.C99 = Std.isC99();
112   Opts.C11 = Std.isC11();
113   Opts.C17 = Std.isC17();
114   Opts.C2x = Std.isC2x();
115   Opts.CPlusPlus = Std.isCPlusPlus();
116   Opts.CPlusPlus11 = Std.isCPlusPlus11();
117   Opts.CPlusPlus14 = Std.isCPlusPlus14();
118   Opts.CPlusPlus17 = Std.isCPlusPlus17();
119   Opts.CPlusPlus20 = Std.isCPlusPlus20();
120   Opts.CPlusPlus23 = Std.isCPlusPlus23();
121   Opts.CPlusPlus26 = Std.isCPlusPlus26();
122   Opts.GNUMode = Std.isGNUMode();
123   Opts.GNUCVersion = 0;
124   Opts.HexFloats = Std.hasHexFloats();
125   Opts.WChar = Std.isCPlusPlus();
126   Opts.Digraphs = Std.hasDigraphs();
127 
128   Opts.HLSL = Lang == Language::HLSL;
129   if (Opts.HLSL && Opts.IncludeDefaultHeader)
130     Includes.push_back("hlsl.h");
131 
132   // Set OpenCL Version.
133   Opts.OpenCL = Std.isOpenCL();
134   if (LangStd == LangStandard::lang_opencl10)
135     Opts.OpenCLVersion = 100;
136   else if (LangStd == LangStandard::lang_opencl11)
137     Opts.OpenCLVersion = 110;
138   else if (LangStd == LangStandard::lang_opencl12)
139     Opts.OpenCLVersion = 120;
140   else if (LangStd == LangStandard::lang_opencl20)
141     Opts.OpenCLVersion = 200;
142   else if (LangStd == LangStandard::lang_opencl30)
143     Opts.OpenCLVersion = 300;
144   else if (LangStd == LangStandard::lang_openclcpp10)
145     Opts.OpenCLCPlusPlusVersion = 100;
146   else if (LangStd == LangStandard::lang_openclcpp2021)
147     Opts.OpenCLCPlusPlusVersion = 202100;
148   else if (LangStd == LangStandard::lang_hlsl2015)
149     Opts.HLSLVersion = (unsigned)LangOptions::HLSL_2015;
150   else if (LangStd == LangStandard::lang_hlsl2016)
151     Opts.HLSLVersion = (unsigned)LangOptions::HLSL_2016;
152   else if (LangStd == LangStandard::lang_hlsl2017)
153     Opts.HLSLVersion = (unsigned)LangOptions::HLSL_2017;
154   else if (LangStd == LangStandard::lang_hlsl2018)
155     Opts.HLSLVersion = (unsigned)LangOptions::HLSL_2018;
156   else if (LangStd == LangStandard::lang_hlsl2021)
157     Opts.HLSLVersion = (unsigned)LangOptions::HLSL_2021;
158   else if (LangStd == LangStandard::lang_hlsl202x)
159     Opts.HLSLVersion = (unsigned)LangOptions::HLSL_202x;
160 
161   // OpenCL has some additional defaults.
162   if (Opts.OpenCL) {
163     Opts.AltiVec = 0;
164     Opts.ZVector = 0;
165     Opts.setDefaultFPContractMode(LangOptions::FPM_On);
166     Opts.OpenCLCPlusPlus = Opts.CPlusPlus;
167     Opts.OpenCLPipes = Opts.getOpenCLCompatibleVersion() == 200;
168     Opts.OpenCLGenericAddressSpace = Opts.getOpenCLCompatibleVersion() == 200;
169 
170     // Include default header file for OpenCL.
171     if (Opts.IncludeDefaultHeader) {
172       if (Opts.DeclareOpenCLBuiltins) {
173         // Only include base header file for builtin types and constants.
174         Includes.push_back("opencl-c-base.h");
175       } else {
176         Includes.push_back("opencl-c.h");
177       }
178     }
179   }
180 
181   Opts.HIP = Lang == Language::HIP;
182   Opts.CUDA = Lang == Language::CUDA || Opts.HIP;
183   if (Opts.HIP) {
184     // HIP toolchain does not support 'Fast' FPOpFusion in backends since it
185     // fuses multiplication/addition instructions without contract flag from
186     // device library functions in LLVM bitcode, which causes accuracy loss in
187     // certain math functions, e.g. tan(-1e20) becomes -0.933 instead of 0.8446.
188     // For device library functions in bitcode to work, 'Strict' or 'Standard'
189     // FPOpFusion options in backends is needed. Therefore 'fast-honor-pragmas'
190     // FP contract option is used to allow fuse across statements in frontend
191     // whereas respecting contract flag in backend.
192     Opts.setDefaultFPContractMode(LangOptions::FPM_FastHonorPragmas);
193   } else if (Opts.CUDA) {
194     if (T.isSPIRV()) {
195       // Emit OpenCL version metadata in LLVM IR when targeting SPIR-V.
196       Opts.OpenCLVersion = 200;
197     }
198     // Allow fuse across statements disregarding pragmas.
199     Opts.setDefaultFPContractMode(LangOptions::FPM_Fast);
200   }
201 
202   Opts.RenderScript = Lang == Language::RenderScript;
203 
204   // OpenCL, C++ and C2x have bool, true, false keywords.
205   Opts.Bool = Opts.OpenCL || Opts.CPlusPlus || Opts.C2x;
206 
207   // OpenCL and HLSL have half keyword
208   Opts.Half = Opts.OpenCL || Opts.HLSL;
209 }
210 
211 FPOptions FPOptions::defaultWithoutTrailingStorage(const LangOptions &LO) {
212   FPOptions result(LO);
213   return result;
214 }
215 
216 FPOptionsOverride FPOptions::getChangesSlow(const FPOptions &Base) const {
217   FPOptions::storage_type OverrideMask = 0;
218 #define OPTION(NAME, TYPE, WIDTH, PREVIOUS)                                    \
219   if (get##NAME() != Base.get##NAME())                                         \
220     OverrideMask |= NAME##Mask;
221 #include "clang/Basic/FPOptions.def"
222   return FPOptionsOverride(*this, OverrideMask);
223 }
224 
225 LLVM_DUMP_METHOD void FPOptions::dump() {
226 #define OPTION(NAME, TYPE, WIDTH, PREVIOUS)                                    \
227   llvm::errs() << "\n " #NAME " " << get##NAME();
228 #include "clang/Basic/FPOptions.def"
229   llvm::errs() << "\n";
230 }
231 
232 LLVM_DUMP_METHOD void FPOptionsOverride::dump() {
233 #define OPTION(NAME, TYPE, WIDTH, PREVIOUS)                                    \
234   if (has##NAME##Override())                                                   \
235     llvm::errs() << "\n " #NAME " Override is " << get##NAME##Override();
236 #include "clang/Basic/FPOptions.def"
237   llvm::errs() << "\n";
238 }
239