1 //===-- llvm-nm.cpp - Symbol table dumping utility for llvm ---------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This program is a utility that works like traditional Unix "nm",
11 // that is, it prints out the names of symbols in a bitcode file,
12 // along with some information about each symbol.
13 //
14 // This "nm" does not print symbols' addresses. It supports many of
15 // the features of GNU "nm", including its different output formats.
16 //
17 //===----------------------------------------------------------------------===//
18
19 #include "llvm/LLVMContext.h"
20 #include "llvm/Module.h"
21 #include "llvm/Bitcode/ReaderWriter.h"
22 #include "llvm/Bitcode/Archive.h"
23 #include "llvm/Object/Archive.h"
24 #include "llvm/Object/ObjectFile.h"
25 #include "llvm/Support/CommandLine.h"
26 #include "llvm/Support/FileSystem.h"
27 #include "llvm/Support/ManagedStatic.h"
28 #include "llvm/Support/MemoryBuffer.h"
29 #include "llvm/Support/PrettyStackTrace.h"
30 #include "llvm/Support/Program.h"
31 #include "llvm/Support/raw_ostream.h"
32 #include "llvm/Support/Signals.h"
33 #include "llvm/Support/Format.h"
34 #include "llvm/Support/system_error.h"
35 #include <algorithm>
36 #include <cctype>
37 #include <cerrno>
38 #include <cstring>
39 #include <vector>
40 using namespace llvm;
41 using namespace object;
42
43 namespace {
44 enum OutputFormatTy { bsd, sysv, posix };
45 cl::opt<OutputFormatTy>
46 OutputFormat("format",
47 cl::desc("Specify output format"),
48 cl::values(clEnumVal(bsd, "BSD format"),
49 clEnumVal(sysv, "System V format"),
50 clEnumVal(posix, "POSIX.2 format"),
51 clEnumValEnd), cl::init(bsd));
52 cl::alias OutputFormat2("f", cl::desc("Alias for --format"),
53 cl::aliasopt(OutputFormat));
54
55 cl::list<std::string>
56 InputFilenames(cl::Positional, cl::desc("<input bitcode files>"),
57 cl::ZeroOrMore);
58
59 cl::opt<bool> UndefinedOnly("undefined-only",
60 cl::desc("Show only undefined symbols"));
61 cl::alias UndefinedOnly2("u", cl::desc("Alias for --undefined-only"),
62 cl::aliasopt(UndefinedOnly));
63
64 cl::opt<bool> DynamicSyms("dynamic",
65 cl::desc("Display the dynamic symbols instead "
66 "of normal symbols."));
67 cl::alias DynamicSyms2("D", cl::desc("Alias for --dynamic"),
68 cl::aliasopt(DynamicSyms));
69
70 cl::opt<bool> DefinedOnly("defined-only",
71 cl::desc("Show only defined symbols"));
72
73 cl::opt<bool> ExternalOnly("extern-only",
74 cl::desc("Show only external symbols"));
75 cl::alias ExternalOnly2("g", cl::desc("Alias for --extern-only"),
76 cl::aliasopt(ExternalOnly));
77
78 cl::opt<bool> BSDFormat("B", cl::desc("Alias for --format=bsd"));
79 cl::opt<bool> POSIXFormat("P", cl::desc("Alias for --format=posix"));
80
81 cl::opt<bool> PrintFileName("print-file-name",
82 cl::desc("Precede each symbol with the object file it came from"));
83
84 cl::alias PrintFileNameA("A", cl::desc("Alias for --print-file-name"),
85 cl::aliasopt(PrintFileName));
86 cl::alias PrintFileNameo("o", cl::desc("Alias for --print-file-name"),
87 cl::aliasopt(PrintFileName));
88
89 cl::opt<bool> DebugSyms("debug-syms",
90 cl::desc("Show all symbols, even debugger only"));
91 cl::alias DebugSymsa("a", cl::desc("Alias for --debug-syms"),
92 cl::aliasopt(DebugSyms));
93
94 cl::opt<bool> NumericSort("numeric-sort",
95 cl::desc("Sort symbols by address"));
96 cl::alias NumericSortn("n", cl::desc("Alias for --numeric-sort"),
97 cl::aliasopt(NumericSort));
98 cl::alias NumericSortv("v", cl::desc("Alias for --numeric-sort"),
99 cl::aliasopt(NumericSort));
100
101 cl::opt<bool> NoSort("no-sort",
102 cl::desc("Show symbols in order encountered"));
103 cl::alias NoSortp("p", cl::desc("Alias for --no-sort"),
104 cl::aliasopt(NoSort));
105
106 cl::opt<bool> PrintSize("print-size",
107 cl::desc("Show symbol size instead of address"));
108 cl::alias PrintSizeS("S", cl::desc("Alias for --print-size"),
109 cl::aliasopt(PrintSize));
110
111 cl::opt<bool> SizeSort("size-sort", cl::desc("Sort symbols by size"));
112
113 bool PrintAddress = true;
114
115 bool MultipleFiles = false;
116
117 std::string ToolName;
118 }
119
120
error(Twine message,Twine path=Twine ())121 static void error(Twine message, Twine path = Twine()) {
122 errs() << ToolName << ": " << path << ": " << message << ".\n";
123 }
124
error(error_code ec,Twine path=Twine ())125 static bool error(error_code ec, Twine path = Twine()) {
126 if (ec) {
127 error(ec.message(), path);
128 return true;
129 }
130 return false;
131 }
132
133 namespace {
134 struct NMSymbol {
135 uint64_t Address;
136 uint64_t Size;
137 char TypeChar;
138 StringRef Name;
139 };
140
CompareSymbolAddress(const NMSymbol & a,const NMSymbol & b)141 static bool CompareSymbolAddress(const NMSymbol &a, const NMSymbol &b) {
142 if (a.Address < b.Address)
143 return true;
144 else if (a.Address == b.Address && a.Name < b.Name)
145 return true;
146 else
147 return false;
148
149 }
150
CompareSymbolSize(const NMSymbol & a,const NMSymbol & b)151 static bool CompareSymbolSize(const NMSymbol &a, const NMSymbol &b) {
152 if (a.Size < b.Size)
153 return true;
154 else if (a.Size == b.Size && a.Name < b.Name)
155 return true;
156 else
157 return false;
158 }
159
CompareSymbolName(const NMSymbol & a,const NMSymbol & b)160 static bool CompareSymbolName(const NMSymbol &a, const NMSymbol &b) {
161 return a.Name < b.Name;
162 }
163
164 StringRef CurrentFilename;
165 typedef std::vector<NMSymbol> SymbolListT;
166 SymbolListT SymbolList;
167 }
168
SortAndPrintSymbolList()169 static void SortAndPrintSymbolList() {
170 if (!NoSort) {
171 if (NumericSort)
172 std::sort(SymbolList.begin(), SymbolList.end(), CompareSymbolAddress);
173 else if (SizeSort)
174 std::sort(SymbolList.begin(), SymbolList.end(), CompareSymbolSize);
175 else
176 std::sort(SymbolList.begin(), SymbolList.end(), CompareSymbolName);
177 }
178
179 if (OutputFormat == posix && MultipleFiles) {
180 outs() << '\n' << CurrentFilename << ":\n";
181 } else if (OutputFormat == bsd && MultipleFiles) {
182 outs() << "\n" << CurrentFilename << ":\n";
183 } else if (OutputFormat == sysv) {
184 outs() << "\n\nSymbols from " << CurrentFilename << ":\n\n"
185 << "Name Value Class Type"
186 << " Size Line Section\n";
187 }
188
189 for (SymbolListT::iterator i = SymbolList.begin(),
190 e = SymbolList.end(); i != e; ++i) {
191 if ((i->TypeChar != 'U') && UndefinedOnly)
192 continue;
193 if ((i->TypeChar == 'U') && DefinedOnly)
194 continue;
195 if (SizeSort && !PrintAddress && i->Size == UnknownAddressOrSize)
196 continue;
197
198 char SymbolAddrStr[10] = "";
199 char SymbolSizeStr[10] = "";
200
201 if (OutputFormat == sysv || i->Address == object::UnknownAddressOrSize)
202 strcpy(SymbolAddrStr, " ");
203 if (OutputFormat == sysv)
204 strcpy(SymbolSizeStr, " ");
205
206 if (i->Address != object::UnknownAddressOrSize)
207 format("%08" PRIx64, i->Address).print(SymbolAddrStr,
208 sizeof(SymbolAddrStr));
209 if (i->Size != object::UnknownAddressOrSize)
210 format("%08" PRIx64, i->Size).print(SymbolSizeStr, sizeof(SymbolSizeStr));
211
212 if (OutputFormat == posix) {
213 outs() << i->Name << " " << i->TypeChar << " "
214 << SymbolAddrStr << SymbolSizeStr << "\n";
215 } else if (OutputFormat == bsd) {
216 if (PrintAddress)
217 outs() << SymbolAddrStr << ' ';
218 if (PrintSize) {
219 outs() << SymbolSizeStr;
220 if (i->Size != object::UnknownAddressOrSize)
221 outs() << ' ';
222 }
223 outs() << i->TypeChar << " " << i->Name << "\n";
224 } else if (OutputFormat == sysv) {
225 std::string PaddedName (i->Name);
226 while (PaddedName.length () < 20)
227 PaddedName += " ";
228 outs() << PaddedName << "|" << SymbolAddrStr << "| "
229 << i->TypeChar
230 << " | |" << SymbolSizeStr << "| |\n";
231 }
232 }
233
234 SymbolList.clear();
235 }
236
TypeCharForSymbol(GlobalValue & GV)237 static char TypeCharForSymbol(GlobalValue &GV) {
238 if (GV.isDeclaration()) return 'U';
239 if (GV.hasLinkOnceLinkage()) return 'C';
240 if (GV.hasCommonLinkage()) return 'C';
241 if (GV.hasWeakLinkage()) return 'W';
242 if (isa<Function>(GV) && GV.hasInternalLinkage()) return 't';
243 if (isa<Function>(GV)) return 'T';
244 if (isa<GlobalVariable>(GV) && GV.hasInternalLinkage()) return 'd';
245 if (isa<GlobalVariable>(GV)) return 'D';
246 if (const GlobalAlias *GA = dyn_cast<GlobalAlias>(&GV)) {
247 const GlobalValue *AliasedGV = GA->getAliasedGlobal();
248 if (isa<Function>(AliasedGV)) return 'T';
249 if (isa<GlobalVariable>(AliasedGV)) return 'D';
250 }
251 return '?';
252 }
253
DumpSymbolNameForGlobalValue(GlobalValue & GV)254 static void DumpSymbolNameForGlobalValue(GlobalValue &GV) {
255 // Private linkage and available_externally linkage don't exist in symtab.
256 if (GV.hasPrivateLinkage() ||
257 GV.hasLinkerPrivateLinkage() ||
258 GV.hasLinkerPrivateWeakLinkage() ||
259 GV.hasLinkerPrivateWeakDefAutoLinkage() ||
260 GV.hasAvailableExternallyLinkage())
261 return;
262 char TypeChar = TypeCharForSymbol(GV);
263 if (GV.hasLocalLinkage () && ExternalOnly)
264 return;
265
266 NMSymbol s;
267 s.Address = object::UnknownAddressOrSize;
268 s.Size = object::UnknownAddressOrSize;
269 s.TypeChar = TypeChar;
270 s.Name = GV.getName();
271 SymbolList.push_back(s);
272 }
273
DumpSymbolNamesFromModule(Module * M)274 static void DumpSymbolNamesFromModule(Module *M) {
275 CurrentFilename = M->getModuleIdentifier();
276 std::for_each (M->begin(), M->end(), DumpSymbolNameForGlobalValue);
277 std::for_each (M->global_begin(), M->global_end(),
278 DumpSymbolNameForGlobalValue);
279 std::for_each (M->alias_begin(), M->alias_end(),
280 DumpSymbolNameForGlobalValue);
281
282 SortAndPrintSymbolList();
283 }
284
DumpSymbolNamesFromObject(ObjectFile * obj)285 static void DumpSymbolNamesFromObject(ObjectFile *obj) {
286 error_code ec;
287 symbol_iterator ibegin = obj->begin_symbols();
288 symbol_iterator iend = obj->end_symbols();
289 if (DynamicSyms) {
290 ibegin = obj->begin_dynamic_symbols();
291 iend = obj->end_dynamic_symbols();
292 }
293 for (symbol_iterator i = ibegin; i != iend; i.increment(ec)) {
294 if (error(ec)) break;
295 uint32_t symflags;
296 if (error(i->getFlags(symflags))) break;
297 if (!DebugSyms && (symflags & SymbolRef::SF_FormatSpecific))
298 continue;
299 NMSymbol s;
300 s.Size = object::UnknownAddressOrSize;
301 s.Address = object::UnknownAddressOrSize;
302 if (PrintSize || SizeSort) {
303 if (error(i->getSize(s.Size))) break;
304 }
305 if (PrintAddress)
306 if (error(i->getAddress(s.Address))) break;
307 if (error(i->getNMTypeChar(s.TypeChar))) break;
308 if (error(i->getName(s.Name))) break;
309 SymbolList.push_back(s);
310 }
311
312 CurrentFilename = obj->getFileName();
313 SortAndPrintSymbolList();
314 }
315
DumpSymbolNamesFromFile(std::string & Filename)316 static void DumpSymbolNamesFromFile(std::string &Filename) {
317 if (Filename != "-" && !sys::fs::exists(Filename)) {
318 errs() << ToolName << ": '" << Filename << "': " << "No such file\n";
319 return;
320 }
321
322 OwningPtr<MemoryBuffer> Buffer;
323 if (error(MemoryBuffer::getFileOrSTDIN(Filename, Buffer), Filename))
324 return;
325
326 sys::fs::file_magic magic = sys::fs::identify_magic(Buffer->getBuffer());
327
328 LLVMContext &Context = getGlobalContext();
329 std::string ErrorMessage;
330 if (magic == sys::fs::file_magic::bitcode) {
331 Module *Result = 0;
332 Result = ParseBitcodeFile(Buffer.get(), Context, &ErrorMessage);
333 if (Result) {
334 DumpSymbolNamesFromModule(Result);
335 delete Result;
336 } else {
337 error(ErrorMessage, Filename);
338 return;
339 }
340 } else if (magic == sys::fs::file_magic::archive) {
341 OwningPtr<Binary> arch;
342 if (error(object::createBinary(Buffer.take(), arch), Filename))
343 return;
344
345 if (object::Archive *a = dyn_cast<object::Archive>(arch.get())) {
346 for (object::Archive::child_iterator i = a->begin_children(),
347 e = a->end_children(); i != e; ++i) {
348 OwningPtr<Binary> child;
349 if (i->getAsBinary(child)) {
350 // Try opening it as a bitcode file.
351 OwningPtr<MemoryBuffer> buff(i->getBuffer());
352 Module *Result = 0;
353 if (buff)
354 Result = ParseBitcodeFile(buff.get(), Context, &ErrorMessage);
355
356 if (Result) {
357 DumpSymbolNamesFromModule(Result);
358 delete Result;
359 }
360 continue;
361 }
362 if (object::ObjectFile *o = dyn_cast<ObjectFile>(child.get())) {
363 outs() << o->getFileName() << ":\n";
364 DumpSymbolNamesFromObject(o);
365 }
366 }
367 }
368 } else if (magic.is_object()) {
369 OwningPtr<Binary> obj;
370 if (error(object::createBinary(Buffer.take(), obj), Filename))
371 return;
372 if (object::ObjectFile *o = dyn_cast<ObjectFile>(obj.get()))
373 DumpSymbolNamesFromObject(o);
374 } else {
375 errs() << ToolName << ": " << Filename << ": "
376 << "unrecognizable file type\n";
377 return;
378 }
379 }
380
main(int argc,char ** argv)381 int main(int argc, char **argv) {
382 // Print a stack trace if we signal out.
383 sys::PrintStackTraceOnErrorSignal();
384 PrettyStackTraceProgram X(argc, argv);
385
386 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
387 cl::ParseCommandLineOptions(argc, argv, "llvm symbol table dumper\n");
388
389 // llvm-nm only reads binary files.
390 if (error(sys::Program::ChangeStdinToBinary()))
391 return 1;
392
393 ToolName = argv[0];
394 if (BSDFormat) OutputFormat = bsd;
395 if (POSIXFormat) OutputFormat = posix;
396
397 // The relative order of these is important. If you pass --size-sort it should
398 // only print out the size. However, if you pass -S --size-sort, it should
399 // print out both the size and address.
400 if (SizeSort && !PrintSize) PrintAddress = false;
401 if (OutputFormat == sysv || SizeSort) PrintSize = true;
402
403 switch (InputFilenames.size()) {
404 case 0: InputFilenames.push_back("-");
405 case 1: break;
406 default: MultipleFiles = true;
407 }
408
409 std::for_each(InputFilenames.begin(), InputFilenames.end(),
410 DumpSymbolNamesFromFile);
411 return 0;
412 }
413