xref: /freebsd/contrib/llvm-project/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp (revision 963f5dc7a30624e95d72fb7f87b8892651164e46)
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) // Deprecated, present in old bitcode
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, COMDAT)
139       STRINGIFY_CODE(MODULE_CODE, VSTOFFSET)
140       STRINGIFY_CODE(MODULE_CODE, METADATA_VALUES_UNUSED)
141       STRINGIFY_CODE(MODULE_CODE, SOURCE_FILENAME)
142       STRINGIFY_CODE(MODULE_CODE, HASH)
143     }
144   case bitc::IDENTIFICATION_BLOCK_ID:
145     switch (CodeID) {
146     default:
147       return None;
148       STRINGIFY_CODE(IDENTIFICATION_CODE, STRING)
149       STRINGIFY_CODE(IDENTIFICATION_CODE, EPOCH)
150     }
151   case bitc::PARAMATTR_BLOCK_ID:
152     switch (CodeID) {
153     default:
154       return None;
155     // FIXME: Should these be different?
156     case bitc::PARAMATTR_CODE_ENTRY_OLD:
157       return "ENTRY";
158     case bitc::PARAMATTR_CODE_ENTRY:
159       return "ENTRY";
160     }
161   case bitc::PARAMATTR_GROUP_BLOCK_ID:
162     switch (CodeID) {
163     default:
164       return None;
165     case bitc::PARAMATTR_GRP_CODE_ENTRY:
166       return "ENTRY";
167     }
168   case bitc::TYPE_BLOCK_ID_NEW:
169     switch (CodeID) {
170     default:
171       return None;
172       STRINGIFY_CODE(TYPE_CODE, NUMENTRY)
173       STRINGIFY_CODE(TYPE_CODE, VOID)
174       STRINGIFY_CODE(TYPE_CODE, FLOAT)
175       STRINGIFY_CODE(TYPE_CODE, DOUBLE)
176       STRINGIFY_CODE(TYPE_CODE, LABEL)
177       STRINGIFY_CODE(TYPE_CODE, OPAQUE)
178       STRINGIFY_CODE(TYPE_CODE, INTEGER)
179       STRINGIFY_CODE(TYPE_CODE, POINTER)
180       STRINGIFY_CODE(TYPE_CODE, HALF)
181       STRINGIFY_CODE(TYPE_CODE, ARRAY)
182       STRINGIFY_CODE(TYPE_CODE, VECTOR)
183       STRINGIFY_CODE(TYPE_CODE, X86_FP80)
184       STRINGIFY_CODE(TYPE_CODE, FP128)
185       STRINGIFY_CODE(TYPE_CODE, PPC_FP128)
186       STRINGIFY_CODE(TYPE_CODE, METADATA)
187       STRINGIFY_CODE(TYPE_CODE, X86_MMX)
188       STRINGIFY_CODE(TYPE_CODE, STRUCT_ANON)
189       STRINGIFY_CODE(TYPE_CODE, STRUCT_NAME)
190       STRINGIFY_CODE(TYPE_CODE, STRUCT_NAMED)
191       STRINGIFY_CODE(TYPE_CODE, FUNCTION)
192       STRINGIFY_CODE(TYPE_CODE, TOKEN)
193       STRINGIFY_CODE(TYPE_CODE, BFLOAT)
194     }
195 
196   case bitc::CONSTANTS_BLOCK_ID:
197     switch (CodeID) {
198     default:
199       return None;
200       STRINGIFY_CODE(CST_CODE, SETTYPE)
201       STRINGIFY_CODE(CST_CODE, NULL)
202       STRINGIFY_CODE(CST_CODE, UNDEF)
203       STRINGIFY_CODE(CST_CODE, INTEGER)
204       STRINGIFY_CODE(CST_CODE, WIDE_INTEGER)
205       STRINGIFY_CODE(CST_CODE, FLOAT)
206       STRINGIFY_CODE(CST_CODE, AGGREGATE)
207       STRINGIFY_CODE(CST_CODE, STRING)
208       STRINGIFY_CODE(CST_CODE, CSTRING)
209       STRINGIFY_CODE(CST_CODE, CE_BINOP)
210       STRINGIFY_CODE(CST_CODE, CE_CAST)
211       STRINGIFY_CODE(CST_CODE, CE_GEP)
212       STRINGIFY_CODE(CST_CODE, CE_INBOUNDS_GEP)
213       STRINGIFY_CODE(CST_CODE, CE_SELECT)
214       STRINGIFY_CODE(CST_CODE, CE_EXTRACTELT)
215       STRINGIFY_CODE(CST_CODE, CE_INSERTELT)
216       STRINGIFY_CODE(CST_CODE, CE_SHUFFLEVEC)
217       STRINGIFY_CODE(CST_CODE, CE_CMP)
218       STRINGIFY_CODE(CST_CODE, INLINEASM)
219       STRINGIFY_CODE(CST_CODE, CE_SHUFVEC_EX)
220       STRINGIFY_CODE(CST_CODE, CE_UNOP)
221       STRINGIFY_CODE(CST_CODE, DSO_LOCAL_EQUIVALENT)
222     case bitc::CST_CODE_BLOCKADDRESS:
223       return "CST_CODE_BLOCKADDRESS";
224       STRINGIFY_CODE(CST_CODE, DATA)
225     }
226   case bitc::FUNCTION_BLOCK_ID:
227     switch (CodeID) {
228     default:
229       return None;
230       STRINGIFY_CODE(FUNC_CODE, DECLAREBLOCKS)
231       STRINGIFY_CODE(FUNC_CODE, INST_BINOP)
232       STRINGIFY_CODE(FUNC_CODE, INST_CAST)
233       STRINGIFY_CODE(FUNC_CODE, INST_GEP_OLD)
234       STRINGIFY_CODE(FUNC_CODE, INST_INBOUNDS_GEP_OLD)
235       STRINGIFY_CODE(FUNC_CODE, INST_SELECT)
236       STRINGIFY_CODE(FUNC_CODE, INST_EXTRACTELT)
237       STRINGIFY_CODE(FUNC_CODE, INST_INSERTELT)
238       STRINGIFY_CODE(FUNC_CODE, INST_SHUFFLEVEC)
239       STRINGIFY_CODE(FUNC_CODE, INST_CMP)
240       STRINGIFY_CODE(FUNC_CODE, INST_RET)
241       STRINGIFY_CODE(FUNC_CODE, INST_BR)
242       STRINGIFY_CODE(FUNC_CODE, INST_SWITCH)
243       STRINGIFY_CODE(FUNC_CODE, INST_INVOKE)
244       STRINGIFY_CODE(FUNC_CODE, INST_UNOP)
245       STRINGIFY_CODE(FUNC_CODE, INST_UNREACHABLE)
246       STRINGIFY_CODE(FUNC_CODE, INST_CLEANUPRET)
247       STRINGIFY_CODE(FUNC_CODE, INST_CATCHRET)
248       STRINGIFY_CODE(FUNC_CODE, INST_CATCHPAD)
249       STRINGIFY_CODE(FUNC_CODE, INST_PHI)
250       STRINGIFY_CODE(FUNC_CODE, INST_ALLOCA)
251       STRINGIFY_CODE(FUNC_CODE, INST_LOAD)
252       STRINGIFY_CODE(FUNC_CODE, INST_VAARG)
253       STRINGIFY_CODE(FUNC_CODE, INST_STORE)
254       STRINGIFY_CODE(FUNC_CODE, INST_EXTRACTVAL)
255       STRINGIFY_CODE(FUNC_CODE, INST_INSERTVAL)
256       STRINGIFY_CODE(FUNC_CODE, INST_CMP2)
257       STRINGIFY_CODE(FUNC_CODE, INST_VSELECT)
258       STRINGIFY_CODE(FUNC_CODE, DEBUG_LOC_AGAIN)
259       STRINGIFY_CODE(FUNC_CODE, INST_CALL)
260       STRINGIFY_CODE(FUNC_CODE, DEBUG_LOC)
261       STRINGIFY_CODE(FUNC_CODE, INST_GEP)
262       STRINGIFY_CODE(FUNC_CODE, OPERAND_BUNDLE)
263       STRINGIFY_CODE(FUNC_CODE, INST_FENCE)
264       STRINGIFY_CODE(FUNC_CODE, INST_ATOMICRMW)
265       STRINGIFY_CODE(FUNC_CODE, INST_LOADATOMIC)
266       STRINGIFY_CODE(FUNC_CODE, INST_STOREATOMIC)
267       STRINGIFY_CODE(FUNC_CODE, INST_CMPXCHG)
268       STRINGIFY_CODE(FUNC_CODE, INST_CALLBR)
269     }
270   case bitc::VALUE_SYMTAB_BLOCK_ID:
271     switch (CodeID) {
272     default:
273       return None;
274       STRINGIFY_CODE(VST_CODE, ENTRY)
275       STRINGIFY_CODE(VST_CODE, BBENTRY)
276       STRINGIFY_CODE(VST_CODE, FNENTRY)
277       STRINGIFY_CODE(VST_CODE, COMBINED_ENTRY)
278     }
279   case bitc::MODULE_STRTAB_BLOCK_ID:
280     switch (CodeID) {
281     default:
282       return None;
283       STRINGIFY_CODE(MST_CODE, ENTRY)
284       STRINGIFY_CODE(MST_CODE, HASH)
285     }
286   case bitc::GLOBALVAL_SUMMARY_BLOCK_ID:
287   case bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID:
288     switch (CodeID) {
289     default:
290       return None;
291       STRINGIFY_CODE(FS, PERMODULE)
292       STRINGIFY_CODE(FS, PERMODULE_PROFILE)
293       STRINGIFY_CODE(FS, PERMODULE_RELBF)
294       STRINGIFY_CODE(FS, PERMODULE_GLOBALVAR_INIT_REFS)
295       STRINGIFY_CODE(FS, PERMODULE_VTABLE_GLOBALVAR_INIT_REFS)
296       STRINGIFY_CODE(FS, COMBINED)
297       STRINGIFY_CODE(FS, COMBINED_PROFILE)
298       STRINGIFY_CODE(FS, COMBINED_GLOBALVAR_INIT_REFS)
299       STRINGIFY_CODE(FS, ALIAS)
300       STRINGIFY_CODE(FS, COMBINED_ALIAS)
301       STRINGIFY_CODE(FS, COMBINED_ORIGINAL_NAME)
302       STRINGIFY_CODE(FS, VERSION)
303       STRINGIFY_CODE(FS, FLAGS)
304       STRINGIFY_CODE(FS, TYPE_TESTS)
305       STRINGIFY_CODE(FS, TYPE_TEST_ASSUME_VCALLS)
306       STRINGIFY_CODE(FS, TYPE_CHECKED_LOAD_VCALLS)
307       STRINGIFY_CODE(FS, TYPE_TEST_ASSUME_CONST_VCALL)
308       STRINGIFY_CODE(FS, TYPE_CHECKED_LOAD_CONST_VCALL)
309       STRINGIFY_CODE(FS, VALUE_GUID)
310       STRINGIFY_CODE(FS, CFI_FUNCTION_DEFS)
311       STRINGIFY_CODE(FS, CFI_FUNCTION_DECLS)
312       STRINGIFY_CODE(FS, TYPE_ID)
313       STRINGIFY_CODE(FS, TYPE_ID_METADATA)
314       STRINGIFY_CODE(FS, BLOCK_COUNT)
315       STRINGIFY_CODE(FS, PARAM_ACCESS)
316     }
317   case bitc::METADATA_ATTACHMENT_ID:
318     switch (CodeID) {
319     default:
320       return None;
321       STRINGIFY_CODE(METADATA, ATTACHMENT)
322     }
323   case bitc::METADATA_BLOCK_ID:
324     switch (CodeID) {
325     default:
326       return None;
327       STRINGIFY_CODE(METADATA, STRING_OLD)
328       STRINGIFY_CODE(METADATA, VALUE)
329       STRINGIFY_CODE(METADATA, NODE)
330       STRINGIFY_CODE(METADATA, NAME)
331       STRINGIFY_CODE(METADATA, DISTINCT_NODE)
332       STRINGIFY_CODE(METADATA, KIND) // Older bitcode has it in a MODULE_BLOCK
333       STRINGIFY_CODE(METADATA, LOCATION)
334       STRINGIFY_CODE(METADATA, OLD_NODE)
335       STRINGIFY_CODE(METADATA, OLD_FN_NODE)
336       STRINGIFY_CODE(METADATA, NAMED_NODE)
337       STRINGIFY_CODE(METADATA, GENERIC_DEBUG)
338       STRINGIFY_CODE(METADATA, SUBRANGE)
339       STRINGIFY_CODE(METADATA, ENUMERATOR)
340       STRINGIFY_CODE(METADATA, BASIC_TYPE)
341       STRINGIFY_CODE(METADATA, FILE)
342       STRINGIFY_CODE(METADATA, DERIVED_TYPE)
343       STRINGIFY_CODE(METADATA, COMPOSITE_TYPE)
344       STRINGIFY_CODE(METADATA, SUBROUTINE_TYPE)
345       STRINGIFY_CODE(METADATA, COMPILE_UNIT)
346       STRINGIFY_CODE(METADATA, SUBPROGRAM)
347       STRINGIFY_CODE(METADATA, LEXICAL_BLOCK)
348       STRINGIFY_CODE(METADATA, LEXICAL_BLOCK_FILE)
349       STRINGIFY_CODE(METADATA, NAMESPACE)
350       STRINGIFY_CODE(METADATA, TEMPLATE_TYPE)
351       STRINGIFY_CODE(METADATA, TEMPLATE_VALUE)
352       STRINGIFY_CODE(METADATA, GLOBAL_VAR)
353       STRINGIFY_CODE(METADATA, LOCAL_VAR)
354       STRINGIFY_CODE(METADATA, EXPRESSION)
355       STRINGIFY_CODE(METADATA, OBJC_PROPERTY)
356       STRINGIFY_CODE(METADATA, IMPORTED_ENTITY)
357       STRINGIFY_CODE(METADATA, MODULE)
358       STRINGIFY_CODE(METADATA, MACRO)
359       STRINGIFY_CODE(METADATA, MACRO_FILE)
360       STRINGIFY_CODE(METADATA, STRINGS)
361       STRINGIFY_CODE(METADATA, GLOBAL_DECL_ATTACHMENT)
362       STRINGIFY_CODE(METADATA, GLOBAL_VAR_EXPR)
363       STRINGIFY_CODE(METADATA, INDEX_OFFSET)
364       STRINGIFY_CODE(METADATA, INDEX)
365       STRINGIFY_CODE(METADATA, ARG_LIST)
366     }
367   case bitc::METADATA_KIND_BLOCK_ID:
368     switch (CodeID) {
369     default:
370       return None;
371       STRINGIFY_CODE(METADATA, KIND)
372     }
373   case bitc::USELIST_BLOCK_ID:
374     switch (CodeID) {
375     default:
376       return None;
377     case bitc::USELIST_CODE_DEFAULT:
378       return "USELIST_CODE_DEFAULT";
379     case bitc::USELIST_CODE_BB:
380       return "USELIST_CODE_BB";
381     }
382 
383   case bitc::OPERAND_BUNDLE_TAGS_BLOCK_ID:
384     switch (CodeID) {
385     default:
386       return None;
387     case bitc::OPERAND_BUNDLE_TAG:
388       return "OPERAND_BUNDLE_TAG";
389     }
390   case bitc::STRTAB_BLOCK_ID:
391     switch (CodeID) {
392     default:
393       return None;
394     case bitc::STRTAB_BLOB:
395       return "BLOB";
396     }
397   case bitc::SYMTAB_BLOCK_ID:
398     switch (CodeID) {
399     default:
400       return None;
401     case bitc::SYMTAB_BLOB:
402       return "BLOB";
403     }
404   }
405 #undef STRINGIFY_CODE
406 }
407 
408 static void printSize(raw_ostream &OS, double Bits) {
409   OS << format("%.2f/%.2fB/%luW", Bits, Bits / 8, (unsigned long)(Bits / 32));
410 }
411 static void printSize(raw_ostream &OS, uint64_t Bits) {
412   OS << format("%lub/%.2fB/%luW", (unsigned long)Bits, (double)Bits / 8,
413                (unsigned long)(Bits / 32));
414 }
415 
416 static Expected<CurStreamTypeType> ReadSignature(BitstreamCursor &Stream) {
417   auto tryRead = [&Stream](char &Dest, size_t size) -> Error {
418     if (Expected<SimpleBitstreamCursor::word_t> MaybeWord = Stream.Read(size))
419       Dest = MaybeWord.get();
420     else
421       return MaybeWord.takeError();
422     return Error::success();
423   };
424 
425   char Signature[6];
426   if (Error Err = tryRead(Signature[0], 8))
427     return std::move(Err);
428   if (Error Err = tryRead(Signature[1], 8))
429     return std::move(Err);
430 
431   // Autodetect the file contents, if it is one we know.
432   if (Signature[0] == 'C' && Signature[1] == 'P') {
433     if (Error Err = tryRead(Signature[2], 8))
434       return std::move(Err);
435     if (Error Err = tryRead(Signature[3], 8))
436       return std::move(Err);
437     if (Signature[2] == 'C' && Signature[3] == 'H')
438       return ClangSerializedASTBitstream;
439   } else if (Signature[0] == 'D' && Signature[1] == 'I') {
440     if (Error Err = tryRead(Signature[2], 8))
441       return std::move(Err);
442     if (Error Err = tryRead(Signature[3], 8))
443       return std::move(Err);
444     if (Signature[2] == 'A' && Signature[3] == 'G')
445       return ClangSerializedDiagnosticsBitstream;
446   } else if (Signature[0] == 'R' && Signature[1] == 'M') {
447     if (Error Err = tryRead(Signature[2], 8))
448       return std::move(Err);
449     if (Error Err = tryRead(Signature[3], 8))
450       return std::move(Err);
451     if (Signature[2] == 'R' && Signature[3] == 'K')
452       return LLVMBitstreamRemarks;
453   } else {
454     if (Error Err = tryRead(Signature[2], 4))
455       return std::move(Err);
456     if (Error Err = tryRead(Signature[3], 4))
457       return std::move(Err);
458     if (Error Err = tryRead(Signature[4], 4))
459       return std::move(Err);
460     if (Error Err = tryRead(Signature[5], 4))
461       return std::move(Err);
462     if (Signature[0] == 'B' && Signature[1] == 'C' && Signature[2] == 0x0 &&
463         Signature[3] == 0xC && Signature[4] == 0xE && Signature[5] == 0xD)
464       return LLVMIRBitstream;
465   }
466   return UnknownBitstream;
467 }
468 
469 static Expected<CurStreamTypeType> analyzeHeader(Optional<BCDumpOptions> O,
470                                                  BitstreamCursor &Stream) {
471   ArrayRef<uint8_t> Bytes = Stream.getBitcodeBytes();
472   const unsigned char *BufPtr = (const unsigned char *)Bytes.data();
473   const unsigned char *EndBufPtr = BufPtr + Bytes.size();
474 
475   // If we have a wrapper header, parse it and ignore the non-bc file
476   // contents. The magic number is 0x0B17C0DE stored in little endian.
477   if (isBitcodeWrapper(BufPtr, EndBufPtr)) {
478     if (Bytes.size() < BWH_HeaderSize)
479       return reportError("Invalid bitcode wrapper header");
480 
481     if (O) {
482       unsigned Magic = support::endian::read32le(&BufPtr[BWH_MagicField]);
483       unsigned Version = support::endian::read32le(&BufPtr[BWH_VersionField]);
484       unsigned Offset = support::endian::read32le(&BufPtr[BWH_OffsetField]);
485       unsigned Size = support::endian::read32le(&BufPtr[BWH_SizeField]);
486       unsigned CPUType = support::endian::read32le(&BufPtr[BWH_CPUTypeField]);
487 
488       O->OS << "<BITCODE_WRAPPER_HEADER"
489             << " Magic=" << format_hex(Magic, 10)
490             << " Version=" << format_hex(Version, 10)
491             << " Offset=" << format_hex(Offset, 10)
492             << " Size=" << format_hex(Size, 10)
493             << " CPUType=" << format_hex(CPUType, 10) << "/>\n";
494     }
495 
496     if (SkipBitcodeWrapperHeader(BufPtr, EndBufPtr, true))
497       return reportError("Invalid bitcode wrapper header");
498   }
499 
500   // Use the cursor modified by skipping the wrapper header.
501   Stream = BitstreamCursor(ArrayRef<uint8_t>(BufPtr, EndBufPtr));
502 
503   return ReadSignature(Stream);
504 }
505 
506 static bool canDecodeBlob(unsigned Code, unsigned BlockID) {
507   return BlockID == bitc::METADATA_BLOCK_ID && Code == bitc::METADATA_STRINGS;
508 }
509 
510 Error BitcodeAnalyzer::decodeMetadataStringsBlob(StringRef Indent,
511                                                  ArrayRef<uint64_t> Record,
512                                                  StringRef Blob,
513                                                  raw_ostream &OS) {
514   if (Blob.empty())
515     return reportError("Cannot decode empty blob.");
516 
517   if (Record.size() != 2)
518     return reportError(
519         "Decoding metadata strings blob needs two record entries.");
520 
521   unsigned NumStrings = Record[0];
522   unsigned StringsOffset = Record[1];
523   OS << " num-strings = " << NumStrings << " {\n";
524 
525   StringRef Lengths = Blob.slice(0, StringsOffset);
526   SimpleBitstreamCursor R(Lengths);
527   StringRef Strings = Blob.drop_front(StringsOffset);
528   do {
529     if (R.AtEndOfStream())
530       return reportError("bad length");
531 
532     Expected<uint32_t> MaybeSize = R.ReadVBR(6);
533     if (!MaybeSize)
534       return MaybeSize.takeError();
535     uint32_t Size = MaybeSize.get();
536     if (Strings.size() < Size)
537       return reportError("truncated chars");
538 
539     OS << Indent << "    '";
540     OS.write_escaped(Strings.slice(0, Size), /*hex=*/true);
541     OS << "'\n";
542     Strings = Strings.drop_front(Size);
543   } while (--NumStrings);
544 
545   OS << Indent << "  }";
546   return Error::success();
547 }
548 
549 BitcodeAnalyzer::BitcodeAnalyzer(StringRef Buffer,
550                                  Optional<StringRef> BlockInfoBuffer)
551     : Stream(Buffer) {
552   if (BlockInfoBuffer)
553     BlockInfoStream.emplace(*BlockInfoBuffer);
554 }
555 
556 Error BitcodeAnalyzer::analyze(Optional<BCDumpOptions> O,
557                                Optional<StringRef> CheckHash) {
558   Expected<CurStreamTypeType> MaybeType = analyzeHeader(O, Stream);
559   if (!MaybeType)
560     return MaybeType.takeError();
561   else
562     CurStreamType = *MaybeType;
563 
564   Stream.setBlockInfo(&BlockInfo);
565 
566   // Read block info from BlockInfoStream, if specified.
567   // The block info must be a top-level block.
568   if (BlockInfoStream) {
569     BitstreamCursor BlockInfoCursor(*BlockInfoStream);
570     Expected<CurStreamTypeType> H = analyzeHeader(O, BlockInfoCursor);
571     if (!H)
572       return H.takeError();
573 
574     while (!BlockInfoCursor.AtEndOfStream()) {
575       Expected<unsigned> MaybeCode = BlockInfoCursor.ReadCode();
576       if (!MaybeCode)
577         return MaybeCode.takeError();
578       if (MaybeCode.get() != bitc::ENTER_SUBBLOCK)
579         return reportError("Invalid record at top-level in block info file");
580 
581       Expected<unsigned> MaybeBlockID = BlockInfoCursor.ReadSubBlockID();
582       if (!MaybeBlockID)
583         return MaybeBlockID.takeError();
584       if (MaybeBlockID.get() == bitc::BLOCKINFO_BLOCK_ID) {
585         Expected<Optional<BitstreamBlockInfo>> MaybeNewBlockInfo =
586             BlockInfoCursor.ReadBlockInfoBlock(/*ReadBlockInfoNames=*/true);
587         if (!MaybeNewBlockInfo)
588           return MaybeNewBlockInfo.takeError();
589         Optional<BitstreamBlockInfo> NewBlockInfo =
590             std::move(MaybeNewBlockInfo.get());
591         if (!NewBlockInfo)
592           return reportError("Malformed BlockInfoBlock in block info file");
593         BlockInfo = std::move(*NewBlockInfo);
594         break;
595       }
596 
597       if (Error Err = BlockInfoCursor.SkipBlock())
598         return Err;
599     }
600   }
601 
602   // Parse the top-level structure.  We only allow blocks at the top-level.
603   while (!Stream.AtEndOfStream()) {
604     Expected<unsigned> MaybeCode = Stream.ReadCode();
605     if (!MaybeCode)
606       return MaybeCode.takeError();
607     if (MaybeCode.get() != bitc::ENTER_SUBBLOCK)
608       return reportError("Invalid record at top-level");
609 
610     Expected<unsigned> MaybeBlockID = Stream.ReadSubBlockID();
611     if (!MaybeBlockID)
612       return MaybeBlockID.takeError();
613 
614     if (Error E = parseBlock(MaybeBlockID.get(), 0, O, CheckHash))
615       return E;
616     ++NumTopBlocks;
617   }
618 
619   return Error::success();
620 }
621 
622 void BitcodeAnalyzer::printStats(BCDumpOptions O,
623                                  Optional<StringRef> Filename) {
624   uint64_t BufferSizeBits = Stream.getBitcodeBytes().size() * CHAR_BIT;
625   // Print a summary of the read file.
626   O.OS << "Summary ";
627   if (Filename)
628     O.OS << "of " << Filename->data() << ":\n";
629   O.OS << "         Total size: ";
630   printSize(O.OS, BufferSizeBits);
631   O.OS << "\n";
632   O.OS << "        Stream type: ";
633   switch (CurStreamType) {
634   case UnknownBitstream:
635     O.OS << "unknown\n";
636     break;
637   case LLVMIRBitstream:
638     O.OS << "LLVM IR\n";
639     break;
640   case ClangSerializedASTBitstream:
641     O.OS << "Clang Serialized AST\n";
642     break;
643   case ClangSerializedDiagnosticsBitstream:
644     O.OS << "Clang Serialized Diagnostics\n";
645     break;
646   case LLVMBitstreamRemarks:
647     O.OS << "LLVM Remarks\n";
648     break;
649   }
650   O.OS << "  # Toplevel Blocks: " << NumTopBlocks << "\n";
651   O.OS << "\n";
652 
653   // Emit per-block stats.
654   O.OS << "Per-block Summary:\n";
655   for (std::map<unsigned, PerBlockIDStats>::iterator I = BlockIDStats.begin(),
656                                                      E = BlockIDStats.end();
657        I != E; ++I) {
658     O.OS << "  Block ID #" << I->first;
659     if (Optional<const char *> BlockName =
660             GetBlockName(I->first, BlockInfo, CurStreamType))
661       O.OS << " (" << *BlockName << ")";
662     O.OS << ":\n";
663 
664     const PerBlockIDStats &Stats = I->second;
665     O.OS << "      Num Instances: " << Stats.NumInstances << "\n";
666     O.OS << "         Total Size: ";
667     printSize(O.OS, Stats.NumBits);
668     O.OS << "\n";
669     double pct = (Stats.NumBits * 100.0) / BufferSizeBits;
670     O.OS << "    Percent of file: " << format("%2.4f%%", pct) << "\n";
671     if (Stats.NumInstances > 1) {
672       O.OS << "       Average Size: ";
673       printSize(O.OS, Stats.NumBits / (double)Stats.NumInstances);
674       O.OS << "\n";
675       O.OS << "  Tot/Avg SubBlocks: " << Stats.NumSubBlocks << "/"
676            << Stats.NumSubBlocks / (double)Stats.NumInstances << "\n";
677       O.OS << "    Tot/Avg Abbrevs: " << Stats.NumAbbrevs << "/"
678            << Stats.NumAbbrevs / (double)Stats.NumInstances << "\n";
679       O.OS << "    Tot/Avg Records: " << Stats.NumRecords << "/"
680            << Stats.NumRecords / (double)Stats.NumInstances << "\n";
681     } else {
682       O.OS << "      Num SubBlocks: " << Stats.NumSubBlocks << "\n";
683       O.OS << "        Num Abbrevs: " << Stats.NumAbbrevs << "\n";
684       O.OS << "        Num Records: " << Stats.NumRecords << "\n";
685     }
686     if (Stats.NumRecords) {
687       double pct = (Stats.NumAbbreviatedRecords * 100.0) / Stats.NumRecords;
688       O.OS << "    Percent Abbrevs: " << format("%2.4f%%", pct) << "\n";
689     }
690     O.OS << "\n";
691 
692     // Print a histogram of the codes we see.
693     if (O.Histogram && !Stats.CodeFreq.empty()) {
694       std::vector<std::pair<unsigned, unsigned>> FreqPairs; // <freq,code>
695       for (unsigned i = 0, e = Stats.CodeFreq.size(); i != e; ++i)
696         if (unsigned Freq = Stats.CodeFreq[i].NumInstances)
697           FreqPairs.push_back(std::make_pair(Freq, i));
698       llvm::stable_sort(FreqPairs);
699       std::reverse(FreqPairs.begin(), FreqPairs.end());
700 
701       O.OS << "\tRecord Histogram:\n";
702       O.OS << "\t\t  Count    # Bits     b/Rec   % Abv  Record Kind\n";
703       for (unsigned i = 0, e = FreqPairs.size(); i != e; ++i) {
704         const PerRecordStats &RecStats = Stats.CodeFreq[FreqPairs[i].second];
705 
706         O.OS << format("\t\t%7d %9lu", RecStats.NumInstances,
707                        (unsigned long)RecStats.TotalBits);
708 
709         if (RecStats.NumInstances > 1)
710           O.OS << format(" %9.1f",
711                          (double)RecStats.TotalBits / RecStats.NumInstances);
712         else
713           O.OS << "          ";
714 
715         if (RecStats.NumAbbrev)
716           O.OS << format(" %7.2f", (double)RecStats.NumAbbrev /
717                                        RecStats.NumInstances * 100);
718         else
719           O.OS << "        ";
720 
721         O.OS << "  ";
722         if (Optional<const char *> CodeName = GetCodeName(
723                 FreqPairs[i].second, I->first, BlockInfo, CurStreamType))
724           O.OS << *CodeName << "\n";
725         else
726           O.OS << "UnknownCode" << FreqPairs[i].second << "\n";
727       }
728       O.OS << "\n";
729     }
730   }
731 }
732 
733 Error BitcodeAnalyzer::parseBlock(unsigned BlockID, unsigned IndentLevel,
734                                   Optional<BCDumpOptions> O,
735                                   Optional<StringRef> CheckHash) {
736   std::string Indent(IndentLevel * 2, ' ');
737   uint64_t BlockBitStart = Stream.GetCurrentBitNo();
738 
739   // Get the statistics for this BlockID.
740   PerBlockIDStats &BlockStats = BlockIDStats[BlockID];
741 
742   BlockStats.NumInstances++;
743 
744   // BLOCKINFO is a special part of the stream.
745   bool DumpRecords = O.hasValue();
746   if (BlockID == bitc::BLOCKINFO_BLOCK_ID) {
747     if (O)
748       O->OS << Indent << "<BLOCKINFO_BLOCK/>\n";
749     Expected<Optional<BitstreamBlockInfo>> MaybeNewBlockInfo =
750         Stream.ReadBlockInfoBlock(/*ReadBlockInfoNames=*/true);
751     if (!MaybeNewBlockInfo)
752       return MaybeNewBlockInfo.takeError();
753     Optional<BitstreamBlockInfo> NewBlockInfo =
754         std::move(MaybeNewBlockInfo.get());
755     if (!NewBlockInfo)
756       return reportError("Malformed BlockInfoBlock");
757     BlockInfo = std::move(*NewBlockInfo);
758     if (Error Err = Stream.JumpToBit(BlockBitStart))
759       return Err;
760     // It's not really interesting to dump the contents of the blockinfo
761     // block.
762     DumpRecords = false;
763   }
764 
765   unsigned NumWords = 0;
766   if (Error Err = Stream.EnterSubBlock(BlockID, &NumWords))
767     return Err;
768 
769   // Keep it for later, when we see a MODULE_HASH record
770   uint64_t BlockEntryPos = Stream.getCurrentByteNo();
771 
772   Optional<const char *> BlockName = None;
773   if (DumpRecords) {
774     O->OS << Indent << "<";
775     if ((BlockName = GetBlockName(BlockID, BlockInfo, CurStreamType)))
776       O->OS << *BlockName;
777     else
778       O->OS << "UnknownBlock" << BlockID;
779 
780     if (!O->Symbolic && BlockName)
781       O->OS << " BlockID=" << BlockID;
782 
783     O->OS << " NumWords=" << NumWords
784           << " BlockCodeSize=" << Stream.getAbbrevIDWidth() << ">\n";
785   }
786 
787   SmallVector<uint64_t, 64> Record;
788 
789   // Keep the offset to the metadata index if seen.
790   uint64_t MetadataIndexOffset = 0;
791 
792   // Read all the records for this block.
793   while (1) {
794     if (Stream.AtEndOfStream())
795       return reportError("Premature end of bitstream");
796 
797     uint64_t RecordStartBit = Stream.GetCurrentBitNo();
798 
799     Expected<BitstreamEntry> MaybeEntry =
800         Stream.advance(BitstreamCursor::AF_DontAutoprocessAbbrevs);
801     if (!MaybeEntry)
802       return MaybeEntry.takeError();
803     BitstreamEntry Entry = MaybeEntry.get();
804 
805     switch (Entry.Kind) {
806     case BitstreamEntry::Error:
807       return reportError("malformed bitcode file");
808     case BitstreamEntry::EndBlock: {
809       uint64_t BlockBitEnd = Stream.GetCurrentBitNo();
810       BlockStats.NumBits += BlockBitEnd - BlockBitStart;
811       if (DumpRecords) {
812         O->OS << Indent << "</";
813         if (BlockName)
814           O->OS << *BlockName << ">\n";
815         else
816           O->OS << "UnknownBlock" << BlockID << ">\n";
817       }
818       return Error::success();
819     }
820 
821     case BitstreamEntry::SubBlock: {
822       uint64_t SubBlockBitStart = Stream.GetCurrentBitNo();
823       if (Error E = parseBlock(Entry.ID, IndentLevel + 1, O, CheckHash))
824         return E;
825       ++BlockStats.NumSubBlocks;
826       uint64_t SubBlockBitEnd = Stream.GetCurrentBitNo();
827 
828       // Don't include subblock sizes in the size of this block.
829       BlockBitStart += SubBlockBitEnd - SubBlockBitStart;
830       continue;
831     }
832     case BitstreamEntry::Record:
833       // The interesting case.
834       break;
835     }
836 
837     if (Entry.ID == bitc::DEFINE_ABBREV) {
838       if (Error Err = Stream.ReadAbbrevRecord())
839         return Err;
840       ++BlockStats.NumAbbrevs;
841       continue;
842     }
843 
844     Record.clear();
845 
846     ++BlockStats.NumRecords;
847 
848     StringRef Blob;
849     uint64_t CurrentRecordPos = Stream.GetCurrentBitNo();
850     Expected<unsigned> MaybeCode = Stream.readRecord(Entry.ID, Record, &Blob);
851     if (!MaybeCode)
852       return MaybeCode.takeError();
853     unsigned Code = MaybeCode.get();
854 
855     // Increment the # occurrences of this code.
856     if (BlockStats.CodeFreq.size() <= Code)
857       BlockStats.CodeFreq.resize(Code + 1);
858     BlockStats.CodeFreq[Code].NumInstances++;
859     BlockStats.CodeFreq[Code].TotalBits +=
860         Stream.GetCurrentBitNo() - RecordStartBit;
861     if (Entry.ID != bitc::UNABBREV_RECORD) {
862       BlockStats.CodeFreq[Code].NumAbbrev++;
863       ++BlockStats.NumAbbreviatedRecords;
864     }
865 
866     if (DumpRecords) {
867       O->OS << Indent << "  <";
868       Optional<const char *> CodeName =
869           GetCodeName(Code, BlockID, BlockInfo, CurStreamType);
870       if (CodeName)
871         O->OS << *CodeName;
872       else
873         O->OS << "UnknownCode" << Code;
874       if (!O->Symbolic && CodeName)
875         O->OS << " codeid=" << Code;
876       const BitCodeAbbrev *Abbv = nullptr;
877       if (Entry.ID != bitc::UNABBREV_RECORD) {
878         Abbv = Stream.getAbbrev(Entry.ID);
879         O->OS << " abbrevid=" << Entry.ID;
880       }
881 
882       for (unsigned i = 0, e = Record.size(); i != e; ++i)
883         O->OS << " op" << i << "=" << (int64_t)Record[i];
884 
885       // If we found a metadata index, let's verify that we had an offset
886       // before and validate its forward reference offset was correct!
887       if (BlockID == bitc::METADATA_BLOCK_ID) {
888         if (Code == bitc::METADATA_INDEX_OFFSET) {
889           if (Record.size() != 2)
890             O->OS << "(Invalid record)";
891           else {
892             auto Offset = Record[0] + (Record[1] << 32);
893             MetadataIndexOffset = Stream.GetCurrentBitNo() + Offset;
894           }
895         }
896         if (Code == bitc::METADATA_INDEX) {
897           O->OS << " (offset ";
898           if (MetadataIndexOffset == RecordStartBit)
899             O->OS << "match)";
900           else
901             O->OS << "mismatch: " << MetadataIndexOffset << " vs "
902                   << RecordStartBit << ")";
903         }
904       }
905 
906       // If we found a module hash, let's verify that it matches!
907       if (BlockID == bitc::MODULE_BLOCK_ID && Code == bitc::MODULE_CODE_HASH &&
908           CheckHash.hasValue()) {
909         if (Record.size() != 5)
910           O->OS << " (invalid)";
911         else {
912           // Recompute the hash and compare it to the one in the bitcode
913           SHA1 Hasher;
914           StringRef Hash;
915           Hasher.update(*CheckHash);
916           {
917             int BlockSize = (CurrentRecordPos / 8) - BlockEntryPos;
918             auto Ptr = Stream.getPointerToByte(BlockEntryPos, BlockSize);
919             Hasher.update(ArrayRef<uint8_t>(Ptr, BlockSize));
920             Hash = Hasher.result();
921           }
922           std::array<char, 20> RecordedHash;
923           int Pos = 0;
924           for (auto &Val : Record) {
925             assert(!(Val >> 32) && "Unexpected high bits set");
926             support::endian::write32be(&RecordedHash[Pos], Val);
927             Pos += 4;
928           }
929           if (Hash == StringRef(RecordedHash.data(), RecordedHash.size()))
930             O->OS << " (match)";
931           else
932             O->OS << " (!mismatch!)";
933         }
934       }
935 
936       O->OS << "/>";
937 
938       if (Abbv) {
939         for (unsigned i = 1, e = Abbv->getNumOperandInfos(); i != e; ++i) {
940           const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
941           if (!Op.isEncoding() || Op.getEncoding() != BitCodeAbbrevOp::Array)
942             continue;
943           assert(i + 2 == e && "Array op not second to last");
944           std::string Str;
945           bool ArrayIsPrintable = true;
946           for (unsigned j = i - 1, je = Record.size(); j != je; ++j) {
947             if (!isPrint(static_cast<unsigned char>(Record[j]))) {
948               ArrayIsPrintable = false;
949               break;
950             }
951             Str += (char)Record[j];
952           }
953           if (ArrayIsPrintable)
954             O->OS << " record string = '" << Str << "'";
955           break;
956         }
957       }
958 
959       if (Blob.data()) {
960         if (canDecodeBlob(Code, BlockID)) {
961           if (Error E = decodeMetadataStringsBlob(Indent, Record, Blob, O->OS))
962             return E;
963         } else {
964           O->OS << " blob data = ";
965           if (O->ShowBinaryBlobs) {
966             O->OS << "'";
967             O->OS.write_escaped(Blob, /*hex=*/true) << "'";
968           } else {
969             bool BlobIsPrintable = true;
970             for (unsigned i = 0, e = Blob.size(); i != e; ++i)
971               if (!isPrint(static_cast<unsigned char>(Blob[i]))) {
972                 BlobIsPrintable = false;
973                 break;
974               }
975 
976             if (BlobIsPrintable)
977               O->OS << "'" << Blob << "'";
978             else
979               O->OS << "unprintable, " << Blob.size() << " bytes.";
980           }
981         }
982       }
983 
984       O->OS << "\n";
985     }
986 
987     // Make sure that we can skip the current record.
988     if (Error Err = Stream.JumpToBit(CurrentRecordPos))
989       return Err;
990     if (Expected<unsigned> Skipped = Stream.skipRecord(Entry.ID))
991       ; // Do nothing.
992     else
993       return Skipped.takeError();
994   }
995 }
996 
997