xref: /llvm-project/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp (revision a7fa35a629e85a72b8cf07a8f95c7c09d9663808)
1 //===- BitcodeAnalyzer.cpp - Internal BitcodeAnalyzer implementation ------===//
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/Bitcode/BitcodeAnalyzer.h"
10 #include "llvm/Bitcode/BitcodeReader.h"
11 #include "llvm/Bitcode/LLVMBitCodes.h"
12 #include "llvm/Bitstream/BitCodes.h"
13 #include "llvm/Bitstream/BitstreamReader.h"
14 #include "llvm/Support/Format.h"
15 #include "llvm/Support/SHA1.h"
16 
17 using namespace llvm;
18 
19 static Error reportError(StringRef Message) {
20   return createStringError(std::errc::illegal_byte_sequence, Message.data());
21 }
22 
23 /// Return a symbolic block name if known, otherwise return null.
24 static Optional<const char *> GetBlockName(unsigned BlockID,
25                                            const BitstreamBlockInfo &BlockInfo,
26                                            CurStreamTypeType CurStreamType) {
27   // Standard blocks for all bitcode files.
28   if (BlockID < bitc::FIRST_APPLICATION_BLOCKID) {
29     if (BlockID == bitc::BLOCKINFO_BLOCK_ID)
30       return "BLOCKINFO_BLOCK";
31     return None;
32   }
33 
34   // Check to see if we have a blockinfo record for this block, with a name.
35   if (const BitstreamBlockInfo::BlockInfo *Info =
36           BlockInfo.getBlockInfo(BlockID)) {
37     if (!Info->Name.empty())
38       return Info->Name.c_str();
39   }
40 
41   if (CurStreamType != LLVMIRBitstream)
42     return None;
43 
44   switch (BlockID) {
45   default:
46     return None;
47   case bitc::OPERAND_BUNDLE_TAGS_BLOCK_ID:
48     return "OPERAND_BUNDLE_TAGS_BLOCK";
49   case bitc::MODULE_BLOCK_ID:
50     return "MODULE_BLOCK";
51   case bitc::PARAMATTR_BLOCK_ID:
52     return "PARAMATTR_BLOCK";
53   case bitc::PARAMATTR_GROUP_BLOCK_ID:
54     return "PARAMATTR_GROUP_BLOCK_ID";
55   case bitc::TYPE_BLOCK_ID_NEW:
56     return "TYPE_BLOCK_ID";
57   case bitc::CONSTANTS_BLOCK_ID:
58     return "CONSTANTS_BLOCK";
59   case bitc::FUNCTION_BLOCK_ID:
60     return "FUNCTION_BLOCK";
61   case bitc::IDENTIFICATION_BLOCK_ID:
62     return "IDENTIFICATION_BLOCK_ID";
63   case bitc::VALUE_SYMTAB_BLOCK_ID:
64     return "VALUE_SYMTAB";
65   case bitc::METADATA_BLOCK_ID:
66     return "METADATA_BLOCK";
67   case bitc::METADATA_KIND_BLOCK_ID:
68     return "METADATA_KIND_BLOCK";
69   case bitc::METADATA_ATTACHMENT_ID:
70     return "METADATA_ATTACHMENT_BLOCK";
71   case bitc::USELIST_BLOCK_ID:
72     return "USELIST_BLOCK_ID";
73   case bitc::GLOBALVAL_SUMMARY_BLOCK_ID:
74     return "GLOBALVAL_SUMMARY_BLOCK";
75   case bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID:
76     return "FULL_LTO_GLOBALVAL_SUMMARY_BLOCK";
77   case bitc::MODULE_STRTAB_BLOCK_ID:
78     return "MODULE_STRTAB_BLOCK";
79   case bitc::STRTAB_BLOCK_ID:
80     return "STRTAB_BLOCK";
81   case bitc::SYMTAB_BLOCK_ID:
82     return "SYMTAB_BLOCK";
83   }
84 }
85 
86 /// Return a symbolic code name if known, otherwise return null.
87 static Optional<const char *> GetCodeName(unsigned CodeID, unsigned BlockID,
88                                           const BitstreamBlockInfo &BlockInfo,
89                                           CurStreamTypeType CurStreamType) {
90   // Standard blocks for all bitcode files.
91   if (BlockID < bitc::FIRST_APPLICATION_BLOCKID) {
92     if (BlockID == bitc::BLOCKINFO_BLOCK_ID) {
93       switch (CodeID) {
94       default:
95         return None;
96       case bitc::BLOCKINFO_CODE_SETBID:
97         return "SETBID";
98       case bitc::BLOCKINFO_CODE_BLOCKNAME:
99         return "BLOCKNAME";
100       case bitc::BLOCKINFO_CODE_SETRECORDNAME:
101         return "SETRECORDNAME";
102       }
103     }
104     return None;
105   }
106 
107   // Check to see if we have a blockinfo record for this record, with a name.
108   if (const BitstreamBlockInfo::BlockInfo *Info =
109           BlockInfo.getBlockInfo(BlockID)) {
110     for (unsigned i = 0, e = Info->RecordNames.size(); i != e; ++i)
111       if (Info->RecordNames[i].first == CodeID)
112         return Info->RecordNames[i].second.c_str();
113   }
114 
115   if (CurStreamType != LLVMIRBitstream)
116     return None;
117 
118 #define STRINGIFY_CODE(PREFIX, CODE)                                           \
119   case bitc::PREFIX##_##CODE:                                                  \
120     return #CODE;
121   switch (BlockID) {
122   default:
123     return None;
124   case bitc::MODULE_BLOCK_ID:
125     switch (CodeID) {
126     default:
127       return None;
128       STRINGIFY_CODE(MODULE_CODE, VERSION)
129       STRINGIFY_CODE(MODULE_CODE, TRIPLE)
130       STRINGIFY_CODE(MODULE_CODE, DATALAYOUT)
131       STRINGIFY_CODE(MODULE_CODE, ASM)
132       STRINGIFY_CODE(MODULE_CODE, SECTIONNAME)
133       STRINGIFY_CODE(MODULE_CODE, DEPLIB) // FIXME: Remove in 4.0
134       STRINGIFY_CODE(MODULE_CODE, GLOBALVAR)
135       STRINGIFY_CODE(MODULE_CODE, FUNCTION)
136       STRINGIFY_CODE(MODULE_CODE, ALIAS)
137       STRINGIFY_CODE(MODULE_CODE, GCNAME)
138       STRINGIFY_CODE(MODULE_CODE, VSTOFFSET)
139       STRINGIFY_CODE(MODULE_CODE, METADATA_VALUES_UNUSED)
140       STRINGIFY_CODE(MODULE_CODE, SOURCE_FILENAME)
141       STRINGIFY_CODE(MODULE_CODE, HASH)
142     }
143   case bitc::IDENTIFICATION_BLOCK_ID:
144     switch (CodeID) {
145     default:
146       return None;
147       STRINGIFY_CODE(IDENTIFICATION_CODE, STRING)
148       STRINGIFY_CODE(IDENTIFICATION_CODE, EPOCH)
149     }
150   case bitc::PARAMATTR_BLOCK_ID:
151     switch (CodeID) {
152     default:
153       return None;
154     // FIXME: Should these be different?
155     case bitc::PARAMATTR_CODE_ENTRY_OLD:
156       return "ENTRY";
157     case bitc::PARAMATTR_CODE_ENTRY:
158       return "ENTRY";
159     }
160   case bitc::PARAMATTR_GROUP_BLOCK_ID:
161     switch (CodeID) {
162     default:
163       return None;
164     case bitc::PARAMATTR_GRP_CODE_ENTRY:
165       return "ENTRY";
166     }
167   case bitc::TYPE_BLOCK_ID_NEW:
168     switch (CodeID) {
169     default:
170       return None;
171       STRINGIFY_CODE(TYPE_CODE, NUMENTRY)
172       STRINGIFY_CODE(TYPE_CODE, VOID)
173       STRINGIFY_CODE(TYPE_CODE, FLOAT)
174       STRINGIFY_CODE(TYPE_CODE, DOUBLE)
175       STRINGIFY_CODE(TYPE_CODE, LABEL)
176       STRINGIFY_CODE(TYPE_CODE, OPAQUE)
177       STRINGIFY_CODE(TYPE_CODE, INTEGER)
178       STRINGIFY_CODE(TYPE_CODE, POINTER)
179       STRINGIFY_CODE(TYPE_CODE, ARRAY)
180       STRINGIFY_CODE(TYPE_CODE, VECTOR)
181       STRINGIFY_CODE(TYPE_CODE, X86_FP80)
182       STRINGIFY_CODE(TYPE_CODE, FP128)
183       STRINGIFY_CODE(TYPE_CODE, PPC_FP128)
184       STRINGIFY_CODE(TYPE_CODE, METADATA)
185       STRINGIFY_CODE(TYPE_CODE, STRUCT_ANON)
186       STRINGIFY_CODE(TYPE_CODE, STRUCT_NAME)
187       STRINGIFY_CODE(TYPE_CODE, STRUCT_NAMED)
188       STRINGIFY_CODE(TYPE_CODE, FUNCTION)
189     }
190 
191   case bitc::CONSTANTS_BLOCK_ID:
192     switch (CodeID) {
193     default:
194       return None;
195       STRINGIFY_CODE(CST_CODE, SETTYPE)
196       STRINGIFY_CODE(CST_CODE, NULL)
197       STRINGIFY_CODE(CST_CODE, UNDEF)
198       STRINGIFY_CODE(CST_CODE, INTEGER)
199       STRINGIFY_CODE(CST_CODE, WIDE_INTEGER)
200       STRINGIFY_CODE(CST_CODE, FLOAT)
201       STRINGIFY_CODE(CST_CODE, AGGREGATE)
202       STRINGIFY_CODE(CST_CODE, STRING)
203       STRINGIFY_CODE(CST_CODE, CSTRING)
204       STRINGIFY_CODE(CST_CODE, CE_BINOP)
205       STRINGIFY_CODE(CST_CODE, CE_CAST)
206       STRINGIFY_CODE(CST_CODE, CE_GEP)
207       STRINGIFY_CODE(CST_CODE, CE_INBOUNDS_GEP)
208       STRINGIFY_CODE(CST_CODE, CE_SELECT)
209       STRINGIFY_CODE(CST_CODE, CE_EXTRACTELT)
210       STRINGIFY_CODE(CST_CODE, CE_INSERTELT)
211       STRINGIFY_CODE(CST_CODE, CE_SHUFFLEVEC)
212       STRINGIFY_CODE(CST_CODE, CE_CMP)
213       STRINGIFY_CODE(CST_CODE, INLINEASM)
214       STRINGIFY_CODE(CST_CODE, CE_SHUFVEC_EX)
215       STRINGIFY_CODE(CST_CODE, CE_UNOP)
216     case bitc::CST_CODE_BLOCKADDRESS:
217       return "CST_CODE_BLOCKADDRESS";
218       STRINGIFY_CODE(CST_CODE, DATA)
219     }
220   case bitc::FUNCTION_BLOCK_ID:
221     switch (CodeID) {
222     default:
223       return None;
224       STRINGIFY_CODE(FUNC_CODE, DECLAREBLOCKS)
225       STRINGIFY_CODE(FUNC_CODE, INST_BINOP)
226       STRINGIFY_CODE(FUNC_CODE, INST_CAST)
227       STRINGIFY_CODE(FUNC_CODE, INST_GEP_OLD)
228       STRINGIFY_CODE(FUNC_CODE, INST_INBOUNDS_GEP_OLD)
229       STRINGIFY_CODE(FUNC_CODE, INST_SELECT)
230       STRINGIFY_CODE(FUNC_CODE, INST_EXTRACTELT)
231       STRINGIFY_CODE(FUNC_CODE, INST_INSERTELT)
232       STRINGIFY_CODE(FUNC_CODE, INST_SHUFFLEVEC)
233       STRINGIFY_CODE(FUNC_CODE, INST_CMP)
234       STRINGIFY_CODE(FUNC_CODE, INST_RET)
235       STRINGIFY_CODE(FUNC_CODE, INST_BR)
236       STRINGIFY_CODE(FUNC_CODE, INST_SWITCH)
237       STRINGIFY_CODE(FUNC_CODE, INST_INVOKE)
238       STRINGIFY_CODE(FUNC_CODE, INST_UNOP)
239       STRINGIFY_CODE(FUNC_CODE, INST_UNREACHABLE)
240       STRINGIFY_CODE(FUNC_CODE, INST_CLEANUPRET)
241       STRINGIFY_CODE(FUNC_CODE, INST_CATCHRET)
242       STRINGIFY_CODE(FUNC_CODE, INST_CATCHPAD)
243       STRINGIFY_CODE(FUNC_CODE, INST_PHI)
244       STRINGIFY_CODE(FUNC_CODE, INST_ALLOCA)
245       STRINGIFY_CODE(FUNC_CODE, INST_LOAD)
246       STRINGIFY_CODE(FUNC_CODE, INST_VAARG)
247       STRINGIFY_CODE(FUNC_CODE, INST_STORE)
248       STRINGIFY_CODE(FUNC_CODE, INST_EXTRACTVAL)
249       STRINGIFY_CODE(FUNC_CODE, INST_INSERTVAL)
250       STRINGIFY_CODE(FUNC_CODE, INST_CMP2)
251       STRINGIFY_CODE(FUNC_CODE, INST_VSELECT)
252       STRINGIFY_CODE(FUNC_CODE, DEBUG_LOC_AGAIN)
253       STRINGIFY_CODE(FUNC_CODE, INST_CALL)
254       STRINGIFY_CODE(FUNC_CODE, DEBUG_LOC)
255       STRINGIFY_CODE(FUNC_CODE, INST_GEP)
256       STRINGIFY_CODE(FUNC_CODE, OPERAND_BUNDLE)
257       STRINGIFY_CODE(FUNC_CODE, INST_FENCE)
258       STRINGIFY_CODE(FUNC_CODE, INST_ATOMICRMW)
259       STRINGIFY_CODE(FUNC_CODE, INST_LOADATOMIC)
260       STRINGIFY_CODE(FUNC_CODE, INST_STOREATOMIC)
261       STRINGIFY_CODE(FUNC_CODE, INST_CMPXCHG)
262       STRINGIFY_CODE(FUNC_CODE, INST_CALLBR)
263     }
264   case bitc::VALUE_SYMTAB_BLOCK_ID:
265     switch (CodeID) {
266     default:
267       return None;
268       STRINGIFY_CODE(VST_CODE, ENTRY)
269       STRINGIFY_CODE(VST_CODE, BBENTRY)
270       STRINGIFY_CODE(VST_CODE, FNENTRY)
271       STRINGIFY_CODE(VST_CODE, COMBINED_ENTRY)
272     }
273   case bitc::MODULE_STRTAB_BLOCK_ID:
274     switch (CodeID) {
275     default:
276       return None;
277       STRINGIFY_CODE(MST_CODE, ENTRY)
278       STRINGIFY_CODE(MST_CODE, HASH)
279     }
280   case bitc::GLOBALVAL_SUMMARY_BLOCK_ID:
281   case bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID:
282     switch (CodeID) {
283     default:
284       return None;
285       STRINGIFY_CODE(FS, PERMODULE)
286       STRINGIFY_CODE(FS, PERMODULE_PROFILE)
287       STRINGIFY_CODE(FS, PERMODULE_RELBF)
288       STRINGIFY_CODE(FS, PERMODULE_GLOBALVAR_INIT_REFS)
289       STRINGIFY_CODE(FS, PERMODULE_VTABLE_GLOBALVAR_INIT_REFS)
290       STRINGIFY_CODE(FS, COMBINED)
291       STRINGIFY_CODE(FS, COMBINED_PROFILE)
292       STRINGIFY_CODE(FS, COMBINED_GLOBALVAR_INIT_REFS)
293       STRINGIFY_CODE(FS, ALIAS)
294       STRINGIFY_CODE(FS, COMBINED_ALIAS)
295       STRINGIFY_CODE(FS, COMBINED_ORIGINAL_NAME)
296       STRINGIFY_CODE(FS, VERSION)
297       STRINGIFY_CODE(FS, FLAGS)
298       STRINGIFY_CODE(FS, TYPE_TESTS)
299       STRINGIFY_CODE(FS, TYPE_TEST_ASSUME_VCALLS)
300       STRINGIFY_CODE(FS, TYPE_CHECKED_LOAD_VCALLS)
301       STRINGIFY_CODE(FS, TYPE_TEST_ASSUME_CONST_VCALL)
302       STRINGIFY_CODE(FS, TYPE_CHECKED_LOAD_CONST_VCALL)
303       STRINGIFY_CODE(FS, VALUE_GUID)
304       STRINGIFY_CODE(FS, CFI_FUNCTION_DEFS)
305       STRINGIFY_CODE(FS, CFI_FUNCTION_DECLS)
306       STRINGIFY_CODE(FS, TYPE_ID)
307       STRINGIFY_CODE(FS, TYPE_ID_METADATA)
308       STRINGIFY_CODE(FS, BLOCK_COUNT)
309     }
310   case bitc::METADATA_ATTACHMENT_ID:
311     switch (CodeID) {
312     default:
313       return None;
314       STRINGIFY_CODE(METADATA, ATTACHMENT)
315     }
316   case bitc::METADATA_BLOCK_ID:
317     switch (CodeID) {
318     default:
319       return None;
320       STRINGIFY_CODE(METADATA, STRING_OLD)
321       STRINGIFY_CODE(METADATA, VALUE)
322       STRINGIFY_CODE(METADATA, NODE)
323       STRINGIFY_CODE(METADATA, NAME)
324       STRINGIFY_CODE(METADATA, DISTINCT_NODE)
325       STRINGIFY_CODE(METADATA, KIND) // Older bitcode has it in a MODULE_BLOCK
326       STRINGIFY_CODE(METADATA, LOCATION)
327       STRINGIFY_CODE(METADATA, OLD_NODE)
328       STRINGIFY_CODE(METADATA, OLD_FN_NODE)
329       STRINGIFY_CODE(METADATA, NAMED_NODE)
330       STRINGIFY_CODE(METADATA, GENERIC_DEBUG)
331       STRINGIFY_CODE(METADATA, SUBRANGE)
332       STRINGIFY_CODE(METADATA, ENUMERATOR)
333       STRINGIFY_CODE(METADATA, BASIC_TYPE)
334       STRINGIFY_CODE(METADATA, FILE)
335       STRINGIFY_CODE(METADATA, DERIVED_TYPE)
336       STRINGIFY_CODE(METADATA, COMPOSITE_TYPE)
337       STRINGIFY_CODE(METADATA, SUBROUTINE_TYPE)
338       STRINGIFY_CODE(METADATA, COMPILE_UNIT)
339       STRINGIFY_CODE(METADATA, SUBPROGRAM)
340       STRINGIFY_CODE(METADATA, LEXICAL_BLOCK)
341       STRINGIFY_CODE(METADATA, LEXICAL_BLOCK_FILE)
342       STRINGIFY_CODE(METADATA, NAMESPACE)
343       STRINGIFY_CODE(METADATA, TEMPLATE_TYPE)
344       STRINGIFY_CODE(METADATA, TEMPLATE_VALUE)
345       STRINGIFY_CODE(METADATA, GLOBAL_VAR)
346       STRINGIFY_CODE(METADATA, LOCAL_VAR)
347       STRINGIFY_CODE(METADATA, EXPRESSION)
348       STRINGIFY_CODE(METADATA, OBJC_PROPERTY)
349       STRINGIFY_CODE(METADATA, IMPORTED_ENTITY)
350       STRINGIFY_CODE(METADATA, MODULE)
351       STRINGIFY_CODE(METADATA, MACRO)
352       STRINGIFY_CODE(METADATA, MACRO_FILE)
353       STRINGIFY_CODE(METADATA, STRINGS)
354       STRINGIFY_CODE(METADATA, GLOBAL_DECL_ATTACHMENT)
355       STRINGIFY_CODE(METADATA, GLOBAL_VAR_EXPR)
356       STRINGIFY_CODE(METADATA, INDEX_OFFSET)
357       STRINGIFY_CODE(METADATA, INDEX)
358     }
359   case bitc::METADATA_KIND_BLOCK_ID:
360     switch (CodeID) {
361     default:
362       return None;
363       STRINGIFY_CODE(METADATA, KIND)
364     }
365   case bitc::USELIST_BLOCK_ID:
366     switch (CodeID) {
367     default:
368       return None;
369     case bitc::USELIST_CODE_DEFAULT:
370       return "USELIST_CODE_DEFAULT";
371     case bitc::USELIST_CODE_BB:
372       return "USELIST_CODE_BB";
373     }
374 
375   case bitc::OPERAND_BUNDLE_TAGS_BLOCK_ID:
376     switch (CodeID) {
377     default:
378       return None;
379     case bitc::OPERAND_BUNDLE_TAG:
380       return "OPERAND_BUNDLE_TAG";
381     }
382   case bitc::STRTAB_BLOCK_ID:
383     switch (CodeID) {
384     default:
385       return None;
386     case bitc::STRTAB_BLOB:
387       return "BLOB";
388     }
389   case bitc::SYMTAB_BLOCK_ID:
390     switch (CodeID) {
391     default:
392       return None;
393     case bitc::SYMTAB_BLOB:
394       return "BLOB";
395     }
396   }
397 #undef STRINGIFY_CODE
398 }
399 
400 static void printSize(raw_ostream &OS, double Bits) {
401   OS << format("%.2f/%.2fB/%luW", Bits, Bits / 8, (unsigned long)(Bits / 32));
402 }
403 static void printSize(raw_ostream &OS, uint64_t Bits) {
404   OS << format("%lub/%.2fB/%luW", (unsigned long)Bits, (double)Bits / 8,
405                (unsigned long)(Bits / 32));
406 }
407 
408 static Expected<CurStreamTypeType> ReadSignature(BitstreamCursor &Stream) {
409   auto tryRead = [&Stream](char &Dest, size_t size) -> Error {
410     if (Expected<SimpleBitstreamCursor::word_t> MaybeWord = Stream.Read(size))
411       Dest = MaybeWord.get();
412     else
413       return MaybeWord.takeError();
414     return Error::success();
415   };
416 
417   char Signature[6];
418   if (Error Err = tryRead(Signature[0], 8))
419     return std::move(Err);
420   if (Error Err = tryRead(Signature[1], 8))
421     return std::move(Err);
422 
423   // Autodetect the file contents, if it is one we know.
424   if (Signature[0] == 'C' && Signature[1] == 'P') {
425     if (Error Err = tryRead(Signature[2], 8))
426       return std::move(Err);
427     if (Error Err = tryRead(Signature[3], 8))
428       return std::move(Err);
429     if (Signature[2] == 'C' && Signature[3] == 'H')
430       return ClangSerializedASTBitstream;
431   } else if (Signature[0] == 'D' && Signature[1] == 'I') {
432     if (Error Err = tryRead(Signature[2], 8))
433       return std::move(Err);
434     if (Error Err = tryRead(Signature[3], 8))
435       return std::move(Err);
436     if (Signature[2] == 'A' && Signature[3] == 'G')
437       return ClangSerializedDiagnosticsBitstream;
438   } else if (Signature[0] == 'R' && Signature[1] == 'M') {
439     if (Error Err = tryRead(Signature[2], 8))
440       return std::move(Err);
441     if (Error Err = tryRead(Signature[3], 8))
442       return std::move(Err);
443     if (Signature[2] == 'R' && Signature[3] == 'K')
444       return LLVMBitstreamRemarks;
445   } else {
446     if (Error Err = tryRead(Signature[2], 4))
447       return std::move(Err);
448     if (Error Err = tryRead(Signature[3], 4))
449       return std::move(Err);
450     if (Error Err = tryRead(Signature[4], 4))
451       return std::move(Err);
452     if (Error Err = tryRead(Signature[5], 4))
453       return std::move(Err);
454     if (Signature[0] == 'B' && Signature[1] == 'C' && Signature[2] == 0x0 &&
455         Signature[3] == 0xC && Signature[4] == 0xE && Signature[5] == 0xD)
456       return LLVMIRBitstream;
457   }
458   return UnknownBitstream;
459 }
460 
461 static Expected<CurStreamTypeType> analyzeHeader(Optional<BCDumpOptions> O,
462                                                  BitstreamCursor &Stream) {
463   ArrayRef<uint8_t> Bytes = Stream.getBitcodeBytes();
464   const unsigned char *BufPtr = (const unsigned char *)Bytes.data();
465   const unsigned char *EndBufPtr = BufPtr + Bytes.size();
466 
467   // If we have a wrapper header, parse it and ignore the non-bc file
468   // contents. The magic number is 0x0B17C0DE stored in little endian.
469   if (isBitcodeWrapper(BufPtr, EndBufPtr)) {
470     if (Bytes.size() < BWH_HeaderSize)
471       return reportError("Invalid bitcode wrapper header");
472 
473     if (O) {
474       unsigned Magic = support::endian::read32le(&BufPtr[BWH_MagicField]);
475       unsigned Version = support::endian::read32le(&BufPtr[BWH_VersionField]);
476       unsigned Offset = support::endian::read32le(&BufPtr[BWH_OffsetField]);
477       unsigned Size = support::endian::read32le(&BufPtr[BWH_SizeField]);
478       unsigned CPUType = support::endian::read32le(&BufPtr[BWH_CPUTypeField]);
479 
480       O->OS << "<BITCODE_WRAPPER_HEADER"
481             << " Magic=" << format_hex(Magic, 10)
482             << " Version=" << format_hex(Version, 10)
483             << " Offset=" << format_hex(Offset, 10)
484             << " Size=" << format_hex(Size, 10)
485             << " CPUType=" << format_hex(CPUType, 10) << "/>\n";
486     }
487 
488     if (SkipBitcodeWrapperHeader(BufPtr, EndBufPtr, true))
489       return reportError("Invalid bitcode wrapper header");
490   }
491 
492   // Use the cursor modified by skipping the wrapper header.
493   Stream = BitstreamCursor(ArrayRef<uint8_t>(BufPtr, EndBufPtr));
494 
495   return ReadSignature(Stream);
496 }
497 
498 static bool canDecodeBlob(unsigned Code, unsigned BlockID) {
499   return BlockID == bitc::METADATA_BLOCK_ID && Code == bitc::METADATA_STRINGS;
500 }
501 
502 Error BitcodeAnalyzer::decodeMetadataStringsBlob(StringRef Indent,
503                                                  ArrayRef<uint64_t> Record,
504                                                  StringRef Blob,
505                                                  raw_ostream &OS) {
506   if (Blob.empty())
507     return reportError("Cannot decode empty blob.");
508 
509   if (Record.size() != 2)
510     return reportError(
511         "Decoding metadata strings blob needs two record entries.");
512 
513   unsigned NumStrings = Record[0];
514   unsigned StringsOffset = Record[1];
515   OS << " num-strings = " << NumStrings << " {\n";
516 
517   StringRef Lengths = Blob.slice(0, StringsOffset);
518   SimpleBitstreamCursor R(Lengths);
519   StringRef Strings = Blob.drop_front(StringsOffset);
520   do {
521     if (R.AtEndOfStream())
522       return reportError("bad length");
523 
524     Expected<uint32_t> MaybeSize = R.ReadVBR(6);
525     if (!MaybeSize)
526       return MaybeSize.takeError();
527     uint32_t Size = MaybeSize.get();
528     if (Strings.size() < Size)
529       return reportError("truncated chars");
530 
531     OS << Indent << "    '";
532     OS.write_escaped(Strings.slice(0, Size), /*hex=*/true);
533     OS << "'\n";
534     Strings = Strings.drop_front(Size);
535   } while (--NumStrings);
536 
537   OS << Indent << "  }";
538   return Error::success();
539 }
540 
541 BitcodeAnalyzer::BitcodeAnalyzer(StringRef Buffer,
542                                  Optional<StringRef> BlockInfoBuffer)
543     : Stream(Buffer) {
544   if (BlockInfoBuffer)
545     BlockInfoStream.emplace(*BlockInfoBuffer);
546 }
547 
548 Error BitcodeAnalyzer::analyze(Optional<BCDumpOptions> O,
549                                Optional<StringRef> CheckHash) {
550   Expected<CurStreamTypeType> MaybeType = analyzeHeader(O, Stream);
551   if (!MaybeType)
552     return MaybeType.takeError();
553   else
554     CurStreamType = *MaybeType;
555 
556   Stream.setBlockInfo(&BlockInfo);
557 
558   // Read block info from BlockInfoStream, if specified.
559   // The block info must be a top-level block.
560   if (BlockInfoStream) {
561     BitstreamCursor BlockInfoCursor(*BlockInfoStream);
562     Expected<CurStreamTypeType> H = analyzeHeader(O, BlockInfoCursor);
563     if (!H)
564       return H.takeError();
565 
566     while (!BlockInfoCursor.AtEndOfStream()) {
567       Expected<unsigned> MaybeCode = BlockInfoCursor.ReadCode();
568       if (!MaybeCode)
569         return MaybeCode.takeError();
570       if (MaybeCode.get() != bitc::ENTER_SUBBLOCK)
571         return reportError("Invalid record at top-level in block info file");
572 
573       Expected<unsigned> MaybeBlockID = BlockInfoCursor.ReadSubBlockID();
574       if (!MaybeBlockID)
575         return MaybeBlockID.takeError();
576       if (MaybeBlockID.get() == bitc::BLOCKINFO_BLOCK_ID) {
577         Expected<Optional<BitstreamBlockInfo>> MaybeNewBlockInfo =
578             BlockInfoCursor.ReadBlockInfoBlock(/*ReadBlockInfoNames=*/true);
579         if (!MaybeNewBlockInfo)
580           return MaybeNewBlockInfo.takeError();
581         Optional<BitstreamBlockInfo> NewBlockInfo =
582             std::move(MaybeNewBlockInfo.get());
583         if (!NewBlockInfo)
584           return reportError("Malformed BlockInfoBlock in block info file");
585         BlockInfo = std::move(*NewBlockInfo);
586         break;
587       }
588 
589       if (Error Err = BlockInfoCursor.SkipBlock())
590         return Err;
591     }
592   }
593 
594   // Parse the top-level structure.  We only allow blocks at the top-level.
595   while (!Stream.AtEndOfStream()) {
596     Expected<unsigned> MaybeCode = Stream.ReadCode();
597     if (!MaybeCode)
598       return MaybeCode.takeError();
599     if (MaybeCode.get() != bitc::ENTER_SUBBLOCK)
600       return reportError("Invalid record at top-level");
601 
602     Expected<unsigned> MaybeBlockID = Stream.ReadSubBlockID();
603     if (!MaybeBlockID)
604       return MaybeBlockID.takeError();
605 
606     if (Error E = parseBlock(MaybeBlockID.get(), 0, O, CheckHash))
607       return E;
608     ++NumTopBlocks;
609   }
610 
611   return Error::success();
612 }
613 
614 void BitcodeAnalyzer::printStats(BCDumpOptions O,
615                                  Optional<StringRef> Filename) {
616   uint64_t BufferSizeBits = Stream.getBitcodeBytes().size() * CHAR_BIT;
617   // Print a summary of the read file.
618   O.OS << "Summary ";
619   if (Filename)
620     O.OS << "of " << Filename->data() << ":\n";
621   O.OS << "         Total size: ";
622   printSize(O.OS, BufferSizeBits);
623   O.OS << "\n";
624   O.OS << "        Stream type: ";
625   switch (CurStreamType) {
626   case UnknownBitstream:
627     O.OS << "unknown\n";
628     break;
629   case LLVMIRBitstream:
630     O.OS << "LLVM IR\n";
631     break;
632   case ClangSerializedASTBitstream:
633     O.OS << "Clang Serialized AST\n";
634     break;
635   case ClangSerializedDiagnosticsBitstream:
636     O.OS << "Clang Serialized Diagnostics\n";
637     break;
638   case LLVMBitstreamRemarks:
639     O.OS << "LLVM Remarks\n";
640     break;
641   }
642   O.OS << "  # Toplevel Blocks: " << NumTopBlocks << "\n";
643   O.OS << "\n";
644 
645   // Emit per-block stats.
646   O.OS << "Per-block Summary:\n";
647   for (std::map<unsigned, PerBlockIDStats>::iterator I = BlockIDStats.begin(),
648                                                      E = BlockIDStats.end();
649        I != E; ++I) {
650     O.OS << "  Block ID #" << I->first;
651     if (Optional<const char *> BlockName =
652             GetBlockName(I->first, BlockInfo, CurStreamType))
653       O.OS << " (" << *BlockName << ")";
654     O.OS << ":\n";
655 
656     const PerBlockIDStats &Stats = I->second;
657     O.OS << "      Num Instances: " << Stats.NumInstances << "\n";
658     O.OS << "         Total Size: ";
659     printSize(O.OS, Stats.NumBits);
660     O.OS << "\n";
661     double pct = (Stats.NumBits * 100.0) / BufferSizeBits;
662     O.OS << "    Percent of file: " << format("%2.4f%%", pct) << "\n";
663     if (Stats.NumInstances > 1) {
664       O.OS << "       Average Size: ";
665       printSize(O.OS, Stats.NumBits / (double)Stats.NumInstances);
666       O.OS << "\n";
667       O.OS << "  Tot/Avg SubBlocks: " << Stats.NumSubBlocks << "/"
668            << Stats.NumSubBlocks / (double)Stats.NumInstances << "\n";
669       O.OS << "    Tot/Avg Abbrevs: " << Stats.NumAbbrevs << "/"
670            << Stats.NumAbbrevs / (double)Stats.NumInstances << "\n";
671       O.OS << "    Tot/Avg Records: " << Stats.NumRecords << "/"
672            << Stats.NumRecords / (double)Stats.NumInstances << "\n";
673     } else {
674       O.OS << "      Num SubBlocks: " << Stats.NumSubBlocks << "\n";
675       O.OS << "        Num Abbrevs: " << Stats.NumAbbrevs << "\n";
676       O.OS << "        Num Records: " << Stats.NumRecords << "\n";
677     }
678     if (Stats.NumRecords) {
679       double pct = (Stats.NumAbbreviatedRecords * 100.0) / Stats.NumRecords;
680       O.OS << "    Percent Abbrevs: " << format("%2.4f%%", pct) << "\n";
681     }
682     O.OS << "\n";
683 
684     // Print a histogram of the codes we see.
685     if (O.Histogram && !Stats.CodeFreq.empty()) {
686       std::vector<std::pair<unsigned, unsigned>> FreqPairs; // <freq,code>
687       for (unsigned i = 0, e = Stats.CodeFreq.size(); i != e; ++i)
688         if (unsigned Freq = Stats.CodeFreq[i].NumInstances)
689           FreqPairs.push_back(std::make_pair(Freq, i));
690       llvm::stable_sort(FreqPairs);
691       std::reverse(FreqPairs.begin(), FreqPairs.end());
692 
693       O.OS << "\tRecord Histogram:\n";
694       O.OS << "\t\t  Count    # Bits     b/Rec   % Abv  Record Kind\n";
695       for (unsigned i = 0, e = FreqPairs.size(); i != e; ++i) {
696         const PerRecordStats &RecStats = Stats.CodeFreq[FreqPairs[i].second];
697 
698         O.OS << format("\t\t%7d %9lu", RecStats.NumInstances,
699                        (unsigned long)RecStats.TotalBits);
700 
701         if (RecStats.NumInstances > 1)
702           O.OS << format(" %9.1f",
703                          (double)RecStats.TotalBits / RecStats.NumInstances);
704         else
705           O.OS << "          ";
706 
707         if (RecStats.NumAbbrev)
708           O.OS << format(" %7.2f", (double)RecStats.NumAbbrev /
709                                        RecStats.NumInstances * 100);
710         else
711           O.OS << "        ";
712 
713         O.OS << "  ";
714         if (Optional<const char *> CodeName = GetCodeName(
715                 FreqPairs[i].second, I->first, BlockInfo, CurStreamType))
716           O.OS << *CodeName << "\n";
717         else
718           O.OS << "UnknownCode" << FreqPairs[i].second << "\n";
719       }
720       O.OS << "\n";
721     }
722   }
723 }
724 
725 Error BitcodeAnalyzer::parseBlock(unsigned BlockID, unsigned IndentLevel,
726                                   Optional<BCDumpOptions> O,
727                                   Optional<StringRef> CheckHash) {
728   std::string Indent(IndentLevel * 2, ' ');
729   uint64_t BlockBitStart = Stream.GetCurrentBitNo();
730 
731   // Get the statistics for this BlockID.
732   PerBlockIDStats &BlockStats = BlockIDStats[BlockID];
733 
734   BlockStats.NumInstances++;
735 
736   // BLOCKINFO is a special part of the stream.
737   bool DumpRecords = O.hasValue();
738   if (BlockID == bitc::BLOCKINFO_BLOCK_ID) {
739     if (O)
740       O->OS << Indent << "<BLOCKINFO_BLOCK/>\n";
741     Expected<Optional<BitstreamBlockInfo>> MaybeNewBlockInfo =
742         Stream.ReadBlockInfoBlock(/*ReadBlockInfoNames=*/true);
743     if (!MaybeNewBlockInfo)
744       return MaybeNewBlockInfo.takeError();
745     Optional<BitstreamBlockInfo> NewBlockInfo =
746         std::move(MaybeNewBlockInfo.get());
747     if (!NewBlockInfo)
748       return reportError("Malformed BlockInfoBlock");
749     BlockInfo = std::move(*NewBlockInfo);
750     if (Error Err = Stream.JumpToBit(BlockBitStart))
751       return Err;
752     // It's not really interesting to dump the contents of the blockinfo
753     // block.
754     DumpRecords = false;
755   }
756 
757   unsigned NumWords = 0;
758   if (Error Err = Stream.EnterSubBlock(BlockID, &NumWords))
759     return Err;
760 
761   // Keep it for later, when we see a MODULE_HASH record
762   uint64_t BlockEntryPos = Stream.getCurrentByteNo();
763 
764   Optional<const char *> BlockName = None;
765   if (DumpRecords) {
766     O->OS << Indent << "<";
767     if ((BlockName = GetBlockName(BlockID, BlockInfo, CurStreamType)))
768       O->OS << *BlockName;
769     else
770       O->OS << "UnknownBlock" << BlockID;
771 
772     if (!O->Symbolic && BlockName)
773       O->OS << " BlockID=" << BlockID;
774 
775     O->OS << " NumWords=" << NumWords
776           << " BlockCodeSize=" << Stream.getAbbrevIDWidth() << ">\n";
777   }
778 
779   SmallVector<uint64_t, 64> Record;
780 
781   // Keep the offset to the metadata index if seen.
782   uint64_t MetadataIndexOffset = 0;
783 
784   // Read all the records for this block.
785   while (1) {
786     if (Stream.AtEndOfStream())
787       return reportError("Premature end of bitstream");
788 
789     uint64_t RecordStartBit = Stream.GetCurrentBitNo();
790 
791     Expected<BitstreamEntry> MaybeEntry =
792         Stream.advance(BitstreamCursor::AF_DontAutoprocessAbbrevs);
793     if (!MaybeEntry)
794       return MaybeEntry.takeError();
795     BitstreamEntry Entry = MaybeEntry.get();
796 
797     switch (Entry.Kind) {
798     case BitstreamEntry::Error:
799       return reportError("malformed bitcode file");
800     case BitstreamEntry::EndBlock: {
801       uint64_t BlockBitEnd = Stream.GetCurrentBitNo();
802       BlockStats.NumBits += BlockBitEnd - BlockBitStart;
803       if (DumpRecords) {
804         O->OS << Indent << "</";
805         if (BlockName)
806           O->OS << *BlockName << ">\n";
807         else
808           O->OS << "UnknownBlock" << BlockID << ">\n";
809       }
810       return Error::success();
811     }
812 
813     case BitstreamEntry::SubBlock: {
814       uint64_t SubBlockBitStart = Stream.GetCurrentBitNo();
815       if (Error E = parseBlock(Entry.ID, IndentLevel + 1, O, CheckHash))
816         return E;
817       ++BlockStats.NumSubBlocks;
818       uint64_t SubBlockBitEnd = Stream.GetCurrentBitNo();
819 
820       // Don't include subblock sizes in the size of this block.
821       BlockBitStart += SubBlockBitEnd - SubBlockBitStart;
822       continue;
823     }
824     case BitstreamEntry::Record:
825       // The interesting case.
826       break;
827     }
828 
829     if (Entry.ID == bitc::DEFINE_ABBREV) {
830       if (Error Err = Stream.ReadAbbrevRecord())
831         return Err;
832       ++BlockStats.NumAbbrevs;
833       continue;
834     }
835 
836     Record.clear();
837 
838     ++BlockStats.NumRecords;
839 
840     StringRef Blob;
841     uint64_t CurrentRecordPos = Stream.GetCurrentBitNo();
842     Expected<unsigned> MaybeCode = Stream.readRecord(Entry.ID, Record, &Blob);
843     if (!MaybeCode)
844       return MaybeCode.takeError();
845     unsigned Code = MaybeCode.get();
846 
847     // Increment the # occurrences of this code.
848     if (BlockStats.CodeFreq.size() <= Code)
849       BlockStats.CodeFreq.resize(Code + 1);
850     BlockStats.CodeFreq[Code].NumInstances++;
851     BlockStats.CodeFreq[Code].TotalBits +=
852         Stream.GetCurrentBitNo() - RecordStartBit;
853     if (Entry.ID != bitc::UNABBREV_RECORD) {
854       BlockStats.CodeFreq[Code].NumAbbrev++;
855       ++BlockStats.NumAbbreviatedRecords;
856     }
857 
858     if (DumpRecords) {
859       O->OS << Indent << "  <";
860       Optional<const char *> CodeName =
861           GetCodeName(Code, BlockID, BlockInfo, CurStreamType);
862       if (CodeName)
863         O->OS << *CodeName;
864       else
865         O->OS << "UnknownCode" << Code;
866       if (!O->Symbolic && CodeName)
867         O->OS << " codeid=" << Code;
868       const BitCodeAbbrev *Abbv = nullptr;
869       if (Entry.ID != bitc::UNABBREV_RECORD) {
870         Abbv = Stream.getAbbrev(Entry.ID);
871         O->OS << " abbrevid=" << Entry.ID;
872       }
873 
874       for (unsigned i = 0, e = Record.size(); i != e; ++i)
875         O->OS << " op" << i << "=" << (int64_t)Record[i];
876 
877       // If we found a metadata index, let's verify that we had an offset
878       // before and validate its forward reference offset was correct!
879       if (BlockID == bitc::METADATA_BLOCK_ID) {
880         if (Code == bitc::METADATA_INDEX_OFFSET) {
881           if (Record.size() != 2)
882             O->OS << "(Invalid record)";
883           else {
884             auto Offset = Record[0] + (Record[1] << 32);
885             MetadataIndexOffset = Stream.GetCurrentBitNo() + Offset;
886           }
887         }
888         if (Code == bitc::METADATA_INDEX) {
889           O->OS << " (offset ";
890           if (MetadataIndexOffset == RecordStartBit)
891             O->OS << "match)";
892           else
893             O->OS << "mismatch: " << MetadataIndexOffset << " vs "
894                   << RecordStartBit << ")";
895         }
896       }
897 
898       // If we found a module hash, let's verify that it matches!
899       if (BlockID == bitc::MODULE_BLOCK_ID && Code == bitc::MODULE_CODE_HASH &&
900           CheckHash.hasValue()) {
901         if (Record.size() != 5)
902           O->OS << " (invalid)";
903         else {
904           // Recompute the hash and compare it to the one in the bitcode
905           SHA1 Hasher;
906           StringRef Hash;
907           Hasher.update(*CheckHash);
908           {
909             int BlockSize = (CurrentRecordPos / 8) - BlockEntryPos;
910             auto Ptr = Stream.getPointerToByte(BlockEntryPos, BlockSize);
911             Hasher.update(ArrayRef<uint8_t>(Ptr, BlockSize));
912             Hash = Hasher.result();
913           }
914           std::array<char, 20> RecordedHash;
915           int Pos = 0;
916           for (auto &Val : Record) {
917             assert(!(Val >> 32) && "Unexpected high bits set");
918             support::endian::write32be(&RecordedHash[Pos], Val);
919             Pos += 4;
920           }
921           if (Hash == StringRef(RecordedHash.data(), RecordedHash.size()))
922             O->OS << " (match)";
923           else
924             O->OS << " (!mismatch!)";
925         }
926       }
927 
928       O->OS << "/>";
929 
930       if (Abbv) {
931         for (unsigned i = 1, e = Abbv->getNumOperandInfos(); i != e; ++i) {
932           const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
933           if (!Op.isEncoding() || Op.getEncoding() != BitCodeAbbrevOp::Array)
934             continue;
935           assert(i + 2 == e && "Array op not second to last");
936           std::string Str;
937           bool ArrayIsPrintable = true;
938           for (unsigned j = i - 1, je = Record.size(); j != je; ++j) {
939             if (!isPrint(static_cast<unsigned char>(Record[j]))) {
940               ArrayIsPrintable = false;
941               break;
942             }
943             Str += (char)Record[j];
944           }
945           if (ArrayIsPrintable)
946             O->OS << " record string = '" << Str << "'";
947           break;
948         }
949       }
950 
951       if (Blob.data()) {
952         if (canDecodeBlob(Code, BlockID)) {
953           if (Error E = decodeMetadataStringsBlob(Indent, Record, Blob, O->OS))
954             return E;
955         } else {
956           O->OS << " blob data = ";
957           if (O->ShowBinaryBlobs) {
958             O->OS << "'";
959             O->OS.write_escaped(Blob, /*hex=*/true) << "'";
960           } else {
961             bool BlobIsPrintable = true;
962             for (unsigned i = 0, e = Blob.size(); i != e; ++i)
963               if (!isPrint(static_cast<unsigned char>(Blob[i]))) {
964                 BlobIsPrintable = false;
965                 break;
966               }
967 
968             if (BlobIsPrintable)
969               O->OS << "'" << Blob << "'";
970             else
971               O->OS << "unprintable, " << Blob.size() << " bytes.";
972           }
973         }
974       }
975 
976       O->OS << "\n";
977     }
978 
979     // Make sure that we can skip the current record.
980     if (Error Err = Stream.JumpToBit(CurrentRecordPos))
981       return Err;
982     if (Expected<unsigned> Skipped = Stream.skipRecord(Entry.ID))
983       ; // Do nothing.
984     else
985       return Skipped.takeError();
986   }
987 }
988 
989