summaryrefslogtreecommitdiff
path: root/lib/Bytecode/Reader/ReaderWrappers.cpp
blob: 81e341655b4b107b8137b5c519356859b2232943 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
//===- ReaderWrappers.cpp - Parse bytecode from file or buffer  -----------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements loading and parsing a bytecode file and parsing a
// bytecode module from a given buffer.
//
//===----------------------------------------------------------------------===//

#include "llvm/Bytecode/Analyzer.h"
#include "llvm/Bytecode/Reader.h"
#include "Reader.h"
#include "llvm/Module.h"
#include "llvm/Instructions.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/System/MappedFile.h"
#include <cerrno>
#include <iostream>
using namespace llvm;

//===----------------------------------------------------------------------===//
// BytecodeFileReader - Read from an mmap'able file descriptor.
//

namespace {
  /// BytecodeFileReader - parses a bytecode file from a file
  ///
  class BytecodeFileReader : public BytecodeReader {
  private:
    sys::MappedFile mapFile;

    BytecodeFileReader(const BytecodeFileReader&); // Do not implement
    void operator=(const BytecodeFileReader &BFR); // Do not implement

  public:
    BytecodeFileReader(const std::string &Filename, llvm::BytecodeHandler* H=0);
  };
}

BytecodeFileReader::BytecodeFileReader(const std::string &Filename,
                                       llvm::BytecodeHandler* H )
  : BytecodeReader(H)
  , mapFile( sys::Path(Filename))
{
  mapFile.map();
  unsigned char* buffer = reinterpret_cast<unsigned char*>(mapFile.base());
  ParseBytecode(buffer, mapFile.size(), Filename);
}

//===----------------------------------------------------------------------===//
// BytecodeBufferReader - Read from a memory buffer
//

namespace {
  /// BytecodeBufferReader - parses a bytecode file from a buffer
  ///
  class BytecodeBufferReader : public BytecodeReader {
  private:
    const unsigned char *Buffer;
    bool MustDelete;

    BytecodeBufferReader(const BytecodeBufferReader&); // Do not implement
    void operator=(const BytecodeBufferReader &BFR);   // Do not implement

  public:
    BytecodeBufferReader(const unsigned char *Buf, unsigned Length,
                         const std::string &ModuleID,
                         llvm::BytecodeHandler* Handler = 0);
    ~BytecodeBufferReader();

  };
}

BytecodeBufferReader::BytecodeBufferReader(const unsigned char *Buf,
                                           unsigned Length,
                                           const std::string &ModuleID,
                                           llvm::BytecodeHandler* H )
  : BytecodeReader(H)
{
  // If not aligned, allocate a new buffer to hold the bytecode...
  const unsigned char *ParseBegin = 0;
  if (reinterpret_cast<uint64_t>(Buf) & 3) {
    Buffer = new unsigned char[Length+4];
    unsigned Offset = 4 - ((intptr_t)Buffer & 3);   // Make sure it's aligned
    ParseBegin = Buffer + Offset;
    memcpy((unsigned char*)ParseBegin, Buf, Length);    // Copy it over
    MustDelete = true;
  } else {
    // If we don't need to copy it over, just use the caller's copy
    ParseBegin = Buffer = Buf;
    MustDelete = false;
  }
  try {
    ParseBytecode(ParseBegin, Length, ModuleID);
  } catch (...) {
    if (MustDelete) delete [] Buffer;
    throw;
  }
}

BytecodeBufferReader::~BytecodeBufferReader() {
  if (MustDelete) delete [] Buffer;
}

//===----------------------------------------------------------------------===//
//  BytecodeStdinReader - Read bytecode from Standard Input
//

namespace {
  /// BytecodeStdinReader - parses a bytecode file from stdin
  ///
  class BytecodeStdinReader : public BytecodeReader {
  private:
    std::vector<unsigned char> FileData;
    unsigned char *FileBuf;

    BytecodeStdinReader(const BytecodeStdinReader&); // Do not implement
    void operator=(const BytecodeStdinReader &BFR);  // Do not implement

  public:
    BytecodeStdinReader( llvm::BytecodeHandler* H = 0 );
  };
}

BytecodeStdinReader::BytecodeStdinReader( BytecodeHandler* H )
  : BytecodeReader(H)
{
  char Buffer[4096*4];

  // Read in all of the data from stdin, we cannot mmap stdin...
  while (std::cin.good()) {
    std::cin.read(Buffer, 4096*4);
    int BlockSize = std::cin.gcount();
    if (0 >= BlockSize)
      break;
    FileData.insert(FileData.end(), Buffer, Buffer+BlockSize);
  }

  if (FileData.empty())
    throw std::string("Standard Input empty!");

  FileBuf = &FileData[0];
  ParseBytecode(FileBuf, FileData.size(), "<stdin>");
}

//===----------------------------------------------------------------------===//
//  Varargs transmogrification code...
//

// CheckVarargs - This is used to automatically translate old-style varargs to
// new style varargs for backwards compatibility.
static ModuleProvider *CheckVarargs(ModuleProvider *MP) {
  Module *M = MP->getModule();

  // Check to see if va_start takes arguments...
  Function *F = M->getNamedFunction("llvm.va_start");
  if (F == 0) return MP;  // No varargs use, just return.

  if (F->getFunctionType()->getNumParams() == 0)
    return MP;  // Modern varargs processing, just return.

  // If we get to this point, we know that we have an old-style module.
  // Materialize the whole thing to perform the rewriting.
  MP->materializeModule();

  // If the user is making use of obsolete varargs intrinsics, adjust them for
  // the user.
  if (Function *F = M->getNamedFunction("llvm.va_start")) {
    assert(F->arg_size() == 1 && "Obsolete va_start takes 1 argument!");

    const Type *RetTy = F->getFunctionType()->getParamType(0);
    RetTy = cast<PointerType>(RetTy)->getElementType();
    Function *NF = M->getOrInsertFunction("llvm.va_start", RetTy, 0);

    for (Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E; )
      if (CallInst *CI = dyn_cast<CallInst>(*I++)) {
        Value *V = new CallInst(NF, "", CI);
        new StoreInst(V, CI->getOperand(1), CI);
        CI->getParent()->getInstList().erase(CI);
      }
    F->setName("");
  }

  if (Function *F = M->getNamedFunction("llvm.va_end")) {
    assert(F->arg_size() == 1 && "Obsolete va_end takes 1 argument!");
    const Type *ArgTy = F->getFunctionType()->getParamType(0);
    ArgTy = cast<PointerType>(ArgTy)->getElementType();
    Function *NF = M->getOrInsertFunction("llvm.va_end", Type::VoidTy,
                                                  ArgTy, 0);

    for (Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E; )
      if (CallInst *CI = dyn_cast<CallInst>(*I++)) {
        Value *V = new LoadInst(CI->getOperand(1), "", CI);
        new CallInst(NF, V, "", CI);
        CI->getParent()->getInstList().erase(CI);
      }
    F->setName("");
  }

  if (Function *F = M->getNamedFunction("llvm.va_copy")) {
    assert(F->arg_size() == 2 && "Obsolete va_copy takes 2 argument!");
    const Type *ArgTy = F->getFunctionType()->getParamType(0);
    ArgTy = cast<PointerType>(ArgTy)->getElementType();
    Function *NF = M->getOrInsertFunction("llvm.va_copy", ArgTy,
                                                  ArgTy, 0);

    for (Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E; )
      if (CallInst *CI = dyn_cast<CallInst>(*I++)) {
        Value *V = new CallInst(NF, CI->getOperand(2), "", CI);
        new StoreInst(V, CI->getOperand(1), CI);
        CI->getParent()->getInstList().erase(CI);
      }
    F->setName("");
  }
  return MP;
}

//===----------------------------------------------------------------------===//
// Wrapper functions
//===----------------------------------------------------------------------===//

/// getBytecodeBufferModuleProvider - lazy function-at-a-time loading from a
/// buffer
ModuleProvider*
llvm::getBytecodeBufferModuleProvider(const unsigned char *Buffer,
                                      unsigned Length,
                                      const std::string &ModuleID,
                                      BytecodeHandler* H ) {
  return CheckVarargs(
      new BytecodeBufferReader(Buffer, Length, ModuleID, H));
}

/// ParseBytecodeBuffer - Parse a given bytecode buffer
///
Module *llvm::ParseBytecodeBuffer(const unsigned char *Buffer, unsigned Length,
                                  const std::string &ModuleID,
                                  std::string *ErrorStr){
  try {
    std::auto_ptr<ModuleProvider>
      AMP(getBytecodeBufferModuleProvider(Buffer, Length, ModuleID));
    return AMP->releaseModule();
  } catch (std::string &err) {
    if (ErrorStr) *ErrorStr = err;
    return 0;
  }
}

/// getBytecodeModuleProvider - lazy function-at-a-time loading from a file
///
ModuleProvider *llvm::getBytecodeModuleProvider(const std::string &Filename,
                                                BytecodeHandler* H) {
  if (Filename != std::string("-"))        // Read from a file...
    return CheckVarargs(new BytecodeFileReader(Filename,H));
  else                                     // Read from stdin
    return CheckVarargs(new BytecodeStdinReader(H));
}

/// ParseBytecodeFile - Parse the given bytecode file
///
Module *llvm::ParseBytecodeFile(const std::string &Filename,
                                std::string *ErrorStr) {
  try {
    std::auto_ptr<ModuleProvider> AMP(getBytecodeModuleProvider(Filename));
    return AMP->releaseModule();
  } catch (std::string &err) {
    if (ErrorStr) *ErrorStr = err;
    return 0;
  }
}

// AnalyzeBytecodeFile - analyze one file
Module* llvm::AnalyzeBytecodeFile(
  const std::string &Filename,  ///< File to analyze
  BytecodeAnalysis& bca,        ///< Statistical output
  std::string *ErrorStr,        ///< Error output
  std::ostream* output          ///< Dump output
)
{
  try {
    BytecodeHandler* analyzerHandler =createBytecodeAnalyzerHandler(bca,output);
    std::auto_ptr<ModuleProvider> AMP(
      getBytecodeModuleProvider(Filename,analyzerHandler));
    return AMP->releaseModule();
  } catch (std::string &err) {
    if (ErrorStr) *ErrorStr = err;
    return 0;
  }
}

// AnalyzeBytecodeBuffer - analyze a buffer
Module* llvm::AnalyzeBytecodeBuffer(
  const unsigned char* Buffer, ///< Pointer to start of bytecode buffer
  unsigned Length,             ///< Size of the bytecode buffer
  const std::string& ModuleID, ///< Identifier for the module
  BytecodeAnalysis& bca,       ///< The results of the analysis
  std::string* ErrorStr,       ///< Errors, if any.
  std::ostream* output         ///< Dump output, if any
)
{
  try {
    BytecodeHandler* hdlr = createBytecodeAnalyzerHandler(bca, output);
    std::auto_ptr<ModuleProvider>
      AMP(getBytecodeBufferModuleProvider(Buffer, Length, ModuleID, hdlr));
    return AMP->releaseModule();
  } catch (std::string &err) {
    if (ErrorStr) *ErrorStr = err;
    return 0;
  }
}

bool llvm::GetBytecodeDependentLibraries(const std::string &fname,
                                         Module::LibraryListType& deplibs) {
  try {
    std::auto_ptr<ModuleProvider> AMP( getBytecodeModuleProvider(fname));
    Module* M = AMP->releaseModule();

    deplibs = M->getLibraries();
    delete M;
    return true;
  } catch (...) {
    deplibs.clear();
    return false;
  }
}

static void getSymbols(Module*M, std::vector<std::string>& symbols) {
  // Loop over global variables
  for (Module::global_iterator GI = M->global_begin(), GE=M->global_end(); GI != GE; ++GI)
    if (!GI->isExternal() && !GI->hasInternalLinkage())
      if (!GI->getName().empty())
        symbols.push_back(GI->getName());

  // Loop over functions.
  for (Module::iterator FI = M->begin(), FE = M->end(); FI != FE; ++FI)
    if (!FI->isExternal() && !FI->hasInternalLinkage())
      if (!FI->getName().empty())
        symbols.push_back(FI->getName());
}

// Get just the externally visible defined symbols from the bytecode
bool llvm::GetBytecodeSymbols(const sys::Path& fName,
                              std::vector<std::string>& symbols) {
  try {
    std::auto_ptr<ModuleProvider> AMP(
        getBytecodeModuleProvider(fName.toString()));

    // Get the module from the provider
    Module* M = AMP->materializeModule();

    // Get the symbols
    getSymbols(M, symbols);

    // Done with the module
    return true;

  } catch (...) {
    return false;
  }
}

ModuleProvider*
llvm::GetBytecodeSymbols(const unsigned char*Buffer, unsigned Length,
                         const std::string& ModuleID,
                         std::vector<std::string>& symbols) {

  ModuleProvider* MP = 0;
  try {
    // Get the module provider
    MP = getBytecodeBufferModuleProvider(Buffer, Length, ModuleID);

    // Get the module from the provider
    Module* M = MP->materializeModule();

    // Get the symbols
    getSymbols(M, symbols);

    // Done with the module. Note that ModuleProvider will delete the
    // Module when it is deleted. Also note that its the caller's responsibility
    // to delete the ModuleProvider.
    return MP;

  } catch (...) {
    // We delete only the ModuleProvider here because its destructor will
    // also delete the Module (we used materializeModule not releaseModule).
    delete MP;
  }
  return 0;
}
// vim: sw=2 ai