xref: /freebsd/contrib/llvm-project/llvm/lib/InterfaceStub/IFSHandler.cpp (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf) 
1 //===- IFSHandler.cpp -----------------------------------------------------===//
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 #include "llvm/InterfaceStub/IFSHandler.h"
10 #include "llvm/ADT/STLExtras.h"
11 #include "llvm/ADT/StringRef.h"
12 #include "llvm/ADT/StringSwitch.h"
13 #include "llvm/ADT/Triple.h"
14 #include "llvm/BinaryFormat/ELF.h"
15 #include "llvm/InterfaceStub/IFSStub.h"
16 #include "llvm/Support/Error.h"
17 #include "llvm/Support/GlobPattern.h"
18 #include "llvm/Support/LineIterator.h"
19 #include "llvm/Support/YAMLTraits.h"
20 #include <functional>
21 #include <optional>
22 
23 using namespace llvm;
24 using namespace llvm::ifs;
25 
26 LLVM_YAML_IS_SEQUENCE_VECTOR(IFSSymbol)
27 
28 namespace llvm {
29 namespace yaml {
30 
31 /// YAML traits for ELFSymbolType.
32 template <> struct ScalarEnumerationTraits<IFSSymbolType> {
33   static void enumeration(IO &IO, IFSSymbolType &SymbolType) {
34     IO.enumCase(SymbolType, "NoType", IFSSymbolType::NoType);
35     IO.enumCase(SymbolType, "Func", IFSSymbolType::Func);
36     IO.enumCase(SymbolType, "Object", IFSSymbolType::Object);
37     IO.enumCase(SymbolType, "TLS", IFSSymbolType::TLS);
38     IO.enumCase(SymbolType, "Unknown", IFSSymbolType::Unknown);
39     // Treat other symbol types as noise, and map to Unknown.
40     if (!IO.outputting() && IO.matchEnumFallback())
41       SymbolType = IFSSymbolType::Unknown;
42   }
43 };
44 
45 template <> struct ScalarTraits<IFSEndiannessType> {
46   static void output(const IFSEndiannessType &Value, void *,
47                      llvm::raw_ostream &Out) {
48     switch (Value) {
49     case IFSEndiannessType::Big:
50       Out << "big";
51       break;
52     case IFSEndiannessType::Little:
53       Out << "little";
54       break;
55     default:
56       llvm_unreachable("Unsupported endianness");
57     }
58   }
59 
60   static StringRef input(StringRef Scalar, void *, IFSEndiannessType &Value) {
61     Value = StringSwitch<IFSEndiannessType>(Scalar)
62                 .Case("big", IFSEndiannessType::Big)
63                 .Case("little", IFSEndiannessType::Little)
64                 .Default(IFSEndiannessType::Unknown);
65     if (Value == IFSEndiannessType::Unknown) {
66       return "Unsupported endianness";
67     }
68     return StringRef();
69   }
70 
71   static QuotingType mustQuote(StringRef) { return QuotingType::None; }
72 };
73 
74 template <> struct ScalarTraits<IFSBitWidthType> {
75   static void output(const IFSBitWidthType &Value, void *,
76                      llvm::raw_ostream &Out) {
77     switch (Value) {
78     case IFSBitWidthType::IFS32:
79       Out << "32";
80       break;
81     case IFSBitWidthType::IFS64:
82       Out << "64";
83       break;
84     default:
85       llvm_unreachable("Unsupported bit width");
86     }
87   }
88 
89   static StringRef input(StringRef Scalar, void *, IFSBitWidthType &Value) {
90     Value = StringSwitch<IFSBitWidthType>(Scalar)
91                 .Case("32", IFSBitWidthType::IFS32)
92                 .Case("64", IFSBitWidthType::IFS64)
93                 .Default(IFSBitWidthType::Unknown);
94     if (Value == IFSBitWidthType::Unknown) {
95       return "Unsupported bit width";
96     }
97     return StringRef();
98   }
99 
100   static QuotingType mustQuote(StringRef) { return QuotingType::None; }
101 };
102 
103 template <> struct MappingTraits<IFSTarget> {
104   static void mapping(IO &IO, IFSTarget &Target) {
105     IO.mapOptional("ObjectFormat", Target.ObjectFormat);
106     IO.mapOptional("Arch", Target.ArchString);
107     IO.mapOptional("Endianness", Target.Endianness);
108     IO.mapOptional("BitWidth", Target.BitWidth);
109   }
110 
111   // Compacts symbol information into a single line.
112   static const bool flow = true; // NOLINT(readability-identifier-naming)
113 };
114 
115 /// YAML traits for ELFSymbol.
116 template <> struct MappingTraits<IFSSymbol> {
117   static void mapping(IO &IO, IFSSymbol &Symbol) {
118     IO.mapRequired("Name", Symbol.Name);
119     IO.mapRequired("Type", Symbol.Type);
120     // The need for symbol size depends on the symbol type.
121     if (Symbol.Type == IFSSymbolType::NoType) {
122       // Size is None, so we are reading it in, or it is non 0 so we
123       // should emit it.
124       if (!Symbol.Size || *Symbol.Size)
125         IO.mapOptional("Size", Symbol.Size);
126     } else if (Symbol.Type != IFSSymbolType::Func) {
127       IO.mapOptional("Size", Symbol.Size);
128     }
129     IO.mapOptional("Undefined", Symbol.Undefined, false);
130     IO.mapOptional("Weak", Symbol.Weak, false);
131     IO.mapOptional("Warning", Symbol.Warning);
132   }
133 
134   // Compacts symbol information into a single line.
135   static const bool flow = true; // NOLINT(readability-identifier-naming)
136 };
137 
138 /// YAML traits for ELFStub objects.
139 template <> struct MappingTraits<IFSStub> {
140   static void mapping(IO &IO, IFSStub &Stub) {
141     if (!IO.mapTag("!ifs-v1", true))
142       IO.setError("Not a .tbe YAML file.");
143     IO.mapRequired("IfsVersion", Stub.IfsVersion);
144     IO.mapOptional("SoName", Stub.SoName);
145     IO.mapOptional("Target", Stub.Target);
146     IO.mapOptional("NeededLibs", Stub.NeededLibs);
147     IO.mapRequired("Symbols", Stub.Symbols);
148   }
149 };
150 
151 /// YAML traits for ELFStubTriple objects.
152 template <> struct MappingTraits<IFSStubTriple> {
153   static void mapping(IO &IO, IFSStubTriple &Stub) {
154     if (!IO.mapTag("!ifs-v1", true))
155       IO.setError("Not a .tbe YAML file.");
156     IO.mapRequired("IfsVersion", Stub.IfsVersion);
157     IO.mapOptional("SoName", Stub.SoName);
158     IO.mapOptional("Target", Stub.Target.Triple);
159     IO.mapOptional("NeededLibs", Stub.NeededLibs);
160     IO.mapRequired("Symbols", Stub.Symbols);
161   }
162 };
163 } // end namespace yaml
164 } // end namespace llvm
165 
166 /// Attempt to determine if a Text stub uses target triple.
167 bool usesTriple(StringRef Buf) {
168   for (line_iterator I(MemoryBufferRef(Buf, "ELFStub")); !I.is_at_eof(); ++I) {
169     StringRef Line = (*I).trim();
170     if (Line.startswith("Target:")) {
171       if (Line == "Target:" || Line.contains("{")) {
172         return false;
173       }
174     }
175   }
176   return true;
177 }
178 
179 Expected<std::unique_ptr<IFSStub>> ifs::readIFSFromBuffer(StringRef Buf) {
180   yaml::Input YamlIn(Buf);
181   std::unique_ptr<IFSStubTriple> Stub(new IFSStubTriple());
182   if (usesTriple(Buf)) {
183     YamlIn >> *Stub;
184   } else {
185     YamlIn >> *static_cast<IFSStub *>(Stub.get());
186   }
187   if (std::error_code Err = YamlIn.error()) {
188     return createStringError(Err, "YAML failed reading as IFS");
189   }
190 
191   if (Stub->IfsVersion > IFSVersionCurrent)
192     return make_error<StringError>(
193         "IFS version " + Stub->IfsVersion.getAsString() + " is unsupported.",
194         std::make_error_code(std::errc::invalid_argument));
195   if (Stub->Target.ArchString) {
196     Stub->Target.Arch =
197         ELF::convertArchNameToEMachine(*Stub->Target.ArchString);
198   }
199   return std::move(Stub);
200 }
201 
202 Error ifs::writeIFSToOutputStream(raw_ostream &OS, const IFSStub &Stub) {
203   yaml::Output YamlOut(OS, nullptr, /*WrapColumn =*/0);
204   std::unique_ptr<IFSStubTriple> CopyStub(new IFSStubTriple(Stub));
205   if (Stub.Target.Arch) {
206     CopyStub->Target.ArchString =
207         std::string(ELF::convertEMachineToArchName(*Stub.Target.Arch));
208   }
209   IFSTarget Target = Stub.Target;
210 
211   if (CopyStub->Target.Triple ||
212       (!CopyStub->Target.ArchString && !CopyStub->Target.Endianness &&
213        !CopyStub->Target.BitWidth))
214     YamlOut << *CopyStub;
215   else
216     YamlOut << *static_cast<IFSStub *>(CopyStub.get());
217   return Error::success();
218 }
219 
220 Error ifs::overrideIFSTarget(
221     IFSStub &Stub, std::optional<IFSArch> OverrideArch,
222     std::optional<IFSEndiannessType> OverrideEndianness,
223     std::optional<IFSBitWidthType> OverrideBitWidth,
224     std::optional<std::string> OverrideTriple) {
225   std::error_code OverrideEC(1, std::generic_category());
226   if (OverrideArch) {
227     if (Stub.Target.Arch && *Stub.Target.Arch != *OverrideArch) {
228       return make_error<StringError>(
229           "Supplied Arch conflicts with the text stub", OverrideEC);
230     }
231     Stub.Target.Arch = *OverrideArch;
232   }
233   if (OverrideEndianness) {
234     if (Stub.Target.Endianness &&
235         *Stub.Target.Endianness != *OverrideEndianness) {
236       return make_error<StringError>(
237           "Supplied Endianness conflicts with the text stub", OverrideEC);
238     }
239     Stub.Target.Endianness = *OverrideEndianness;
240   }
241   if (OverrideBitWidth) {
242     if (Stub.Target.BitWidth && *Stub.Target.BitWidth != *OverrideBitWidth) {
243       return make_error<StringError>(
244           "Supplied BitWidth conflicts with the text stub", OverrideEC);
245     }
246     Stub.Target.BitWidth = *OverrideBitWidth;
247   }
248   if (OverrideTriple) {
249     if (Stub.Target.Triple && *Stub.Target.Triple != *OverrideTriple) {
250       return make_error<StringError>(
251           "Supplied Triple conflicts with the text stub", OverrideEC);
252     }
253     Stub.Target.Triple = *OverrideTriple;
254   }
255   return Error::success();
256 }
257 
258 Error ifs::validateIFSTarget(IFSStub &Stub, bool ParseTriple) {
259   std::error_code ValidationEC(1, std::generic_category());
260   if (Stub.Target.Triple) {
261     if (Stub.Target.Arch || Stub.Target.BitWidth || Stub.Target.Endianness ||
262         Stub.Target.ObjectFormat) {
263       return make_error<StringError>(
264           "Target triple cannot be used simultaneously with ELF target format",
265           ValidationEC);
266     }
267     if (ParseTriple) {
268       IFSTarget TargetFromTriple = parseTriple(*Stub.Target.Triple);
269       Stub.Target.Arch = TargetFromTriple.Arch;
270       Stub.Target.BitWidth = TargetFromTriple.BitWidth;
271       Stub.Target.Endianness = TargetFromTriple.Endianness;
272     }
273     return Error::success();
274   }
275   if (!Stub.Target.Arch || !Stub.Target.BitWidth || !Stub.Target.Endianness) {
276     // TODO: unify the error message.
277     if (!Stub.Target.Arch) {
278       return make_error<StringError>("Arch is not defined in the text stub",
279                                      ValidationEC);
280     }
281     if (!Stub.Target.BitWidth) {
282       return make_error<StringError>("BitWidth is not defined in the text stub",
283                                      ValidationEC);
284     }
285     if (!Stub.Target.Endianness) {
286       return make_error<StringError>(
287           "Endianness is not defined in the text stub", ValidationEC);
288     }
289   }
290   return Error::success();
291 }
292 
293 IFSTarget ifs::parseTriple(StringRef TripleStr) {
294   Triple IFSTriple(TripleStr);
295   IFSTarget RetTarget;
296   // TODO: Implement a Triple Arch enum to e_machine map.
297   switch (IFSTriple.getArch()) {
298   case Triple::ArchType::aarch64:
299     RetTarget.Arch = (IFSArch)ELF::EM_AARCH64;
300     break;
301   case Triple::ArchType::x86_64:
302     RetTarget.Arch = (IFSArch)ELF::EM_X86_64;
303     break;
304   default:
305     RetTarget.Arch = (IFSArch)ELF::EM_NONE;
306   }
307   RetTarget.Endianness = IFSTriple.isLittleEndian() ? IFSEndiannessType::Little
308                                                     : IFSEndiannessType::Big;
309   RetTarget.BitWidth =
310       IFSTriple.isArch64Bit() ? IFSBitWidthType::IFS64 : IFSBitWidthType::IFS32;
311   return RetTarget;
312 }
313 
314 void ifs::stripIFSTarget(IFSStub &Stub, bool StripTriple, bool StripArch,
315                          bool StripEndianness, bool StripBitWidth) {
316   if (StripTriple || StripArch) {
317     Stub.Target.Arch.reset();
318     Stub.Target.ArchString.reset();
319   }
320   if (StripTriple || StripEndianness) {
321     Stub.Target.Endianness.reset();
322   }
323   if (StripTriple || StripBitWidth) {
324     Stub.Target.BitWidth.reset();
325   }
326   if (StripTriple) {
327     Stub.Target.Triple.reset();
328   }
329   if (!Stub.Target.Arch && !Stub.Target.BitWidth && !Stub.Target.Endianness) {
330     Stub.Target.ObjectFormat.reset();
331   }
332 }
333 
334 Error ifs::filterIFSSyms(IFSStub &Stub, bool StripUndefined,
335                          const std::vector<std::string> &Exclude) {
336   std::function<bool(const IFSSymbol &)> Filter = [](const IFSSymbol &) {
337     return false;
338   };
339 
340   if (StripUndefined) {
341     Filter = [Filter](const IFSSymbol &Sym) {
342       return Sym.Undefined || Filter(Sym);
343     };
344   }
345 
346   for (StringRef Glob : Exclude) {
347     Expected<llvm::GlobPattern> PatternOrErr = llvm::GlobPattern::create(Glob);
348     if (!PatternOrErr)
349       return PatternOrErr.takeError();
350     Filter = [Pattern = *PatternOrErr, Filter](const IFSSymbol &Sym) {
351       return Pattern.match(Sym.Name) || Filter(Sym);
352     };
353   }
354 
355   llvm::erase_if(Stub.Symbols, Filter);
356 
357   return Error::success();
358 }
359