LLVM  8.0.0svn
MetadataLoader.cpp
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1 //===- MetadataLoader.cpp - Internal BitcodeReader implementation ---------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "MetadataLoader.h"
11 #include "ValueList.h"
12 
13 #include "llvm/ADT/APFloat.h"
14 #include "llvm/ADT/APInt.h"
15 #include "llvm/ADT/ArrayRef.h"
16 #include "llvm/ADT/DenseMap.h"
17 #include "llvm/ADT/DenseSet.h"
18 #include "llvm/ADT/None.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/ADT/SmallString.h"
21 #include "llvm/ADT/SmallVector.h"
22 #include "llvm/ADT/Statistic.h"
23 #include "llvm/ADT/StringRef.h"
24 #include "llvm/ADT/Twine.h"
28 #include "llvm/IR/Argument.h"
29 #include "llvm/IR/Attributes.h"
30 #include "llvm/IR/AutoUpgrade.h"
31 #include "llvm/IR/BasicBlock.h"
32 #include "llvm/IR/CallingConv.h"
33 #include "llvm/IR/Comdat.h"
34 #include "llvm/IR/Constant.h"
35 #include "llvm/IR/Constants.h"
36 #include "llvm/IR/DebugInfo.h"
38 #include "llvm/IR/DebugLoc.h"
39 #include "llvm/IR/DerivedTypes.h"
41 #include "llvm/IR/Function.h"
42 #include "llvm/IR/GVMaterializer.h"
43 #include "llvm/IR/GlobalAlias.h"
44 #include "llvm/IR/GlobalIFunc.h"
46 #include "llvm/IR/GlobalObject.h"
47 #include "llvm/IR/GlobalValue.h"
48 #include "llvm/IR/GlobalVariable.h"
49 #include "llvm/IR/InlineAsm.h"
50 #include "llvm/IR/InstrTypes.h"
51 #include "llvm/IR/Instruction.h"
52 #include "llvm/IR/Instructions.h"
53 #include "llvm/IR/IntrinsicInst.h"
54 #include "llvm/IR/Intrinsics.h"
55 #include "llvm/IR/LLVMContext.h"
56 #include "llvm/IR/Module.h"
58 #include "llvm/IR/OperandTraits.h"
59 #include "llvm/IR/TrackingMDRef.h"
60 #include "llvm/IR/Type.h"
61 #include "llvm/IR/ValueHandle.h"
63 #include "llvm/Support/Casting.h"
65 #include "llvm/Support/Compiler.h"
66 #include "llvm/Support/Debug.h"
67 #include "llvm/Support/Error.h"
72 #include <algorithm>
73 #include <cassert>
74 #include <cstddef>
75 #include <cstdint>
76 #include <deque>
77 #include <limits>
78 #include <map>
79 #include <memory>
80 #include <string>
81 #include <system_error>
82 #include <tuple>
83 #include <utility>
84 #include <vector>
85 
86 using namespace llvm;
87 
88 #define DEBUG_TYPE "bitcode-reader"
89 
90 STATISTIC(NumMDStringLoaded, "Number of MDStrings loaded");
91 STATISTIC(NumMDNodeTemporary, "Number of MDNode::Temporary created");
92 STATISTIC(NumMDRecordLoaded, "Number of Metadata records loaded");
93 
94 /// Flag whether we need to import full type definitions for ThinLTO.
95 /// Currently needed for Darwin and LLDB.
97  "import-full-type-definitions", cl::init(false), cl::Hidden,
98  cl::desc("Import full type definitions for ThinLTO."));
99 
101  "disable-ondemand-mds-loading", cl::init(false), cl::Hidden,
102  cl::desc("Force disable the lazy-loading on-demand of metadata when "
103  "loading bitcode for importing."));
104 
105 namespace {
106 
107 static int64_t unrotateSign(uint64_t U) { return U & 1 ? ~(U >> 1) : U >> 1; }
108 
109 class BitcodeReaderMetadataList {
110  /// Array of metadata references.
111  ///
112  /// Don't use std::vector here. Some versions of libc++ copy (instead of
113  /// move) on resize, and TrackingMDRef is very expensive to copy.
114  SmallVector<TrackingMDRef, 1> MetadataPtrs;
115 
116  /// The set of indices in MetadataPtrs above of forward references that were
117  /// generated.
118  SmallDenseSet<unsigned, 1> ForwardReference;
119 
120  /// The set of indices in MetadataPtrs above of Metadata that need to be
121  /// resolved.
122  SmallDenseSet<unsigned, 1> UnresolvedNodes;
123 
124  /// Structures for resolving old type refs.
125  struct {
130  } OldTypeRefs;
131 
133 
134 public:
135  BitcodeReaderMetadataList(LLVMContext &C) : Context(C) {}
136 
137  // vector compatibility methods
138  unsigned size() const { return MetadataPtrs.size(); }
139  void resize(unsigned N) { MetadataPtrs.resize(N); }
140  void push_back(Metadata *MD) { MetadataPtrs.emplace_back(MD); }
141  void clear() { MetadataPtrs.clear(); }
142  Metadata *back() const { return MetadataPtrs.back(); }
143  void pop_back() { MetadataPtrs.pop_back(); }
144  bool empty() const { return MetadataPtrs.empty(); }
145 
146  Metadata *operator[](unsigned i) const {
147  assert(i < MetadataPtrs.size());
148  return MetadataPtrs[i];
149  }
150 
151  Metadata *lookup(unsigned I) const {
152  if (I < MetadataPtrs.size())
153  return MetadataPtrs[I];
154  return nullptr;
155  }
156 
157  void shrinkTo(unsigned N) {
158  assert(N <= size() && "Invalid shrinkTo request!");
159  assert(ForwardReference.empty() && "Unexpected forward refs");
160  assert(UnresolvedNodes.empty() && "Unexpected unresolved node");
161  MetadataPtrs.resize(N);
162  }
163 
164  /// Return the given metadata, creating a replaceable forward reference if
165  /// necessary.
166  Metadata *getMetadataFwdRef(unsigned Idx);
167 
168  /// Return the given metadata only if it is fully resolved.
169  ///
170  /// Gives the same result as \a lookup(), unless \a MDNode::isResolved()
171  /// would give \c false.
172  Metadata *getMetadataIfResolved(unsigned Idx);
173 
174  MDNode *getMDNodeFwdRefOrNull(unsigned Idx);
175  void assignValue(Metadata *MD, unsigned Idx);
176  void tryToResolveCycles();
177  bool hasFwdRefs() const { return !ForwardReference.empty(); }
178  int getNextFwdRef() {
179  assert(hasFwdRefs());
180  return *ForwardReference.begin();
181  }
182 
183  /// Upgrade a type that had an MDString reference.
184  void addTypeRef(MDString &UUID, DICompositeType &CT);
185 
186  /// Upgrade a type that had an MDString reference.
187  Metadata *upgradeTypeRef(Metadata *MaybeUUID);
188 
189  /// Upgrade a type ref array that may have MDString references.
190  Metadata *upgradeTypeRefArray(Metadata *MaybeTuple);
191 
192 private:
193  Metadata *resolveTypeRefArray(Metadata *MaybeTuple);
194 };
195 
196 void BitcodeReaderMetadataList::assignValue(Metadata *MD, unsigned Idx) {
197  if (auto *MDN = dyn_cast<MDNode>(MD))
198  if (!MDN->isResolved())
199  UnresolvedNodes.insert(Idx);
200 
201  if (Idx == size()) {
202  push_back(MD);
203  return;
204  }
205 
206  if (Idx >= size())
207  resize(Idx + 1);
208 
209  TrackingMDRef &OldMD = MetadataPtrs[Idx];
210  if (!OldMD) {
211  OldMD.reset(MD);
212  return;
213  }
214 
215  // If there was a forward reference to this value, replace it.
216  TempMDTuple PrevMD(cast<MDTuple>(OldMD.get()));
217  PrevMD->replaceAllUsesWith(MD);
218  ForwardReference.erase(Idx);
219 }
220 
221 Metadata *BitcodeReaderMetadataList::getMetadataFwdRef(unsigned Idx) {
222  if (Idx >= size())
223  resize(Idx + 1);
224 
225  if (Metadata *MD = MetadataPtrs[Idx])
226  return MD;
227 
228  // Track forward refs to be resolved later.
229  ForwardReference.insert(Idx);
230 
231  // Create and return a placeholder, which will later be RAUW'd.
232  ++NumMDNodeTemporary;
233  Metadata *MD = MDNode::getTemporary(Context, None).release();
234  MetadataPtrs[Idx].reset(MD);
235  return MD;
236 }
237 
238 Metadata *BitcodeReaderMetadataList::getMetadataIfResolved(unsigned Idx) {
239  Metadata *MD = lookup(Idx);
240  if (auto *N = dyn_cast_or_null<MDNode>(MD))
241  if (!N->isResolved())
242  return nullptr;
243  return MD;
244 }
245 
246 MDNode *BitcodeReaderMetadataList::getMDNodeFwdRefOrNull(unsigned Idx) {
247  return dyn_cast_or_null<MDNode>(getMetadataFwdRef(Idx));
248 }
249 
250 void BitcodeReaderMetadataList::tryToResolveCycles() {
251  if (!ForwardReference.empty())
252  // Still forward references... can't resolve cycles.
253  return;
254 
255  // Give up on finding a full definition for any forward decls that remain.
256  for (const auto &Ref : OldTypeRefs.FwdDecls)
257  OldTypeRefs.Final.insert(Ref);
258  OldTypeRefs.FwdDecls.clear();
259 
260  // Upgrade from old type ref arrays. In strange cases, this could add to
261  // OldTypeRefs.Unknown.
262  for (const auto &Array : OldTypeRefs.Arrays)
263  Array.second->replaceAllUsesWith(resolveTypeRefArray(Array.first.get()));
264  OldTypeRefs.Arrays.clear();
265 
266  // Replace old string-based type refs with the resolved node, if possible.
267  // If we haven't seen the node, leave it to the verifier to complain about
268  // the invalid string reference.
269  for (const auto &Ref : OldTypeRefs.Unknown) {
270  if (DICompositeType *CT = OldTypeRefs.Final.lookup(Ref.first))
271  Ref.second->replaceAllUsesWith(CT);
272  else
273  Ref.second->replaceAllUsesWith(Ref.first);
274  }
275  OldTypeRefs.Unknown.clear();
276 
277  if (UnresolvedNodes.empty())
278  // Nothing to do.
279  return;
280 
281  // Resolve any cycles.
282  for (unsigned I : UnresolvedNodes) {
283  auto &MD = MetadataPtrs[I];
284  auto *N = dyn_cast_or_null<MDNode>(MD);
285  if (!N)
286  continue;
287 
288  assert(!N->isTemporary() && "Unexpected forward reference");
289  N->resolveCycles();
290  }
291 
292  // Make sure we return early again until there's another unresolved ref.
293  UnresolvedNodes.clear();
294 }
295 
296 void BitcodeReaderMetadataList::addTypeRef(MDString &UUID,
297  DICompositeType &CT) {
298  assert(CT.getRawIdentifier() == &UUID && "Mismatched UUID");
299  if (CT.isForwardDecl())
300  OldTypeRefs.FwdDecls.insert(std::make_pair(&UUID, &CT));
301  else
302  OldTypeRefs.Final.insert(std::make_pair(&UUID, &CT));
303 }
304 
305 Metadata *BitcodeReaderMetadataList::upgradeTypeRef(Metadata *MaybeUUID) {
306  auto *UUID = dyn_cast_or_null<MDString>(MaybeUUID);
307  if (LLVM_LIKELY(!UUID))
308  return MaybeUUID;
309 
310  if (auto *CT = OldTypeRefs.Final.lookup(UUID))
311  return CT;
312 
313  auto &Ref = OldTypeRefs.Unknown[UUID];
314  if (!Ref)
315  Ref = MDNode::getTemporary(Context, None);
316  return Ref.get();
317 }
318 
319 Metadata *BitcodeReaderMetadataList::upgradeTypeRefArray(Metadata *MaybeTuple) {
320  auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple);
321  if (!Tuple || Tuple->isDistinct())
322  return MaybeTuple;
323 
324  // Look through the array immediately if possible.
325  if (!Tuple->isTemporary())
326  return resolveTypeRefArray(Tuple);
327 
328  // Create and return a placeholder to use for now. Eventually
329  // resolveTypeRefArrays() will be resolve this forward reference.
330  OldTypeRefs.Arrays.emplace_back(
331  std::piecewise_construct, std::forward_as_tuple(Tuple),
332  std::forward_as_tuple(MDTuple::getTemporary(Context, None)));
333  return OldTypeRefs.Arrays.back().second.get();
334 }
335 
336 Metadata *BitcodeReaderMetadataList::resolveTypeRefArray(Metadata *MaybeTuple) {
337  auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple);
338  if (!Tuple || Tuple->isDistinct())
339  return MaybeTuple;
340 
341  // Look through the DITypeRefArray, upgrading each DITypeRef.
343  Ops.reserve(Tuple->getNumOperands());
344  for (Metadata *MD : Tuple->operands())
345  Ops.push_back(upgradeTypeRef(MD));
346 
347  return MDTuple::get(Context, Ops);
348 }
349 
350 namespace {
351 
352 class PlaceholderQueue {
353  // Placeholders would thrash around when moved, so store in a std::deque
354  // instead of some sort of vector.
355  std::deque<DistinctMDOperandPlaceholder> PHs;
356 
357 public:
358  ~PlaceholderQueue() {
359  assert(empty() && "PlaceholderQueue hasn't been flushed before being destroyed");
360  }
361  bool empty() { return PHs.empty(); }
362  DistinctMDOperandPlaceholder &getPlaceholderOp(unsigned ID);
363  void flush(BitcodeReaderMetadataList &MetadataList);
364 
365  /// Return the list of temporaries nodes in the queue, these need to be
366  /// loaded before we can flush the queue.
367  void getTemporaries(BitcodeReaderMetadataList &MetadataList,
368  DenseSet<unsigned> &Temporaries) {
369  for (auto &PH : PHs) {
370  auto ID = PH.getID();
371  auto *MD = MetadataList.lookup(ID);
372  if (!MD) {
373  Temporaries.insert(ID);
374  continue;
375  }
376  auto *N = dyn_cast_or_null<MDNode>(MD);
377  if (N && N->isTemporary())
378  Temporaries.insert(ID);
379  }
380  }
381 };
382 
383 } // end anonymous namespace
384 
385 DistinctMDOperandPlaceholder &PlaceholderQueue::getPlaceholderOp(unsigned ID) {
386  PHs.emplace_back(ID);
387  return PHs.back();
388 }
389 
390 void PlaceholderQueue::flush(BitcodeReaderMetadataList &MetadataList) {
391  while (!PHs.empty()) {
392  auto *MD = MetadataList.lookup(PHs.front().getID());
393  assert(MD && "Flushing placeholder on unassigned MD");
394 #ifndef NDEBUG
395  if (auto *MDN = dyn_cast<MDNode>(MD))
396  assert(MDN->isResolved() &&
397  "Flushing Placeholder while cycles aren't resolved");
398 #endif
399  PHs.front().replaceUseWith(MD);
400  PHs.pop_front();
401  }
402 }
403 
404 } // anonynous namespace
405 
406 static Error error(const Twine &Message) {
407  return make_error<StringError>(
409 }
410 
412  BitcodeReaderMetadataList MetadataList;
413  BitcodeReaderValueList &ValueList;
414  BitstreamCursor &Stream;
416  Module &TheModule;
417  std::function<Type *(unsigned)> getTypeByID;
418 
419  /// Cursor associated with the lazy-loading of Metadata. This is the easy way
420  /// to keep around the right "context" (Abbrev list) to be able to jump in
421  /// the middle of the metadata block and load any record.
422  BitstreamCursor IndexCursor;
423 
424  /// Index that keeps track of MDString values.
425  std::vector<StringRef> MDStringRef;
426 
427  /// On-demand loading of a single MDString. Requires the index above to be
428  /// populated.
429  MDString *lazyLoadOneMDString(unsigned Idx);
430 
431  /// Index that keeps track of where to find a metadata record in the stream.
432  std::vector<uint64_t> GlobalMetadataBitPosIndex;
433 
434  /// Populate the index above to enable lazily loading of metadata, and load
435  /// the named metadata as well as the transitively referenced global
436  /// Metadata.
437  Expected<bool> lazyLoadModuleMetadataBlock();
438 
439  /// On-demand loading of a single metadata. Requires the index above to be
440  /// populated.
441  void lazyLoadOneMetadata(unsigned Idx, PlaceholderQueue &Placeholders);
442 
443  // Keep mapping of seens pair of old-style CU <-> SP, and update pointers to
444  // point from SP to CU after a block is completly parsed.
445  std::vector<std::pair<DICompileUnit *, Metadata *>> CUSubprograms;
446 
447  /// Functions that need to be matched with subprograms when upgrading old
448  /// metadata.
450 
451  // Map the bitcode's custom MDKind ID to the Module's MDKind ID.
453 
454  bool StripTBAA = false;
455  bool HasSeenOldLoopTags = false;
456  bool NeedUpgradeToDIGlobalVariableExpression = false;
457  bool NeedDeclareExpressionUpgrade = false;
458 
459  /// True if metadata is being parsed for a module being ThinLTO imported.
460  bool IsImporting = false;
461 
462  Error parseOneMetadata(SmallVectorImpl<uint64_t> &Record, unsigned Code,
463  PlaceholderQueue &Placeholders, StringRef Blob,
464  unsigned &NextMetadataNo);
465  Error parseMetadataStrings(ArrayRef<uint64_t> Record, StringRef Blob,
466  function_ref<void(StringRef)> CallBack);
467  Error parseGlobalObjectAttachment(GlobalObject &GO,
468  ArrayRef<uint64_t> Record);
469  Error parseMetadataKindRecord(SmallVectorImpl<uint64_t> &Record);
470 
471  void resolveForwardRefsAndPlaceholders(PlaceholderQueue &Placeholders);
472 
473  /// Upgrade old-style CU <-> SP pointers to point from SP to CU.
474  void upgradeCUSubprograms() {
475  for (auto CU_SP : CUSubprograms)
476  if (auto *SPs = dyn_cast_or_null<MDTuple>(CU_SP.second))
477  for (auto &Op : SPs->operands())
478  if (auto *SP = dyn_cast_or_null<DISubprogram>(Op))
479  SP->replaceUnit(CU_SP.first);
480  CUSubprograms.clear();
481  }
482 
483  /// Upgrade old-style bare DIGlobalVariables to DIGlobalVariableExpressions.
484  void upgradeCUVariables() {
485  if (!NeedUpgradeToDIGlobalVariableExpression)
486  return;
487 
488  // Upgrade list of variables attached to the CUs.
489  if (NamedMDNode *CUNodes = TheModule.getNamedMetadata("llvm.dbg.cu"))
490  for (unsigned I = 0, E = CUNodes->getNumOperands(); I != E; ++I) {
491  auto *CU = cast<DICompileUnit>(CUNodes->getOperand(I));
492  if (auto *GVs = dyn_cast_or_null<MDTuple>(CU->getRawGlobalVariables()))
493  for (unsigned I = 0; I < GVs->getNumOperands(); I++)
494  if (auto *GV =
495  dyn_cast_or_null<DIGlobalVariable>(GVs->getOperand(I))) {
497  Context, GV, DIExpression::get(Context, {}));
498  GVs->replaceOperandWith(I, DGVE);
499  }
500  }
501 
502  // Upgrade variables attached to globals.
503  for (auto &GV : TheModule.globals()) {
505  GV.getMetadata(LLVMContext::MD_dbg, MDs);
506  GV.eraseMetadata(LLVMContext::MD_dbg);
507  for (auto *MD : MDs)
508  if (auto *DGV = dyn_cast_or_null<DIGlobalVariable>(MD)) {
510  Context, DGV, DIExpression::get(Context, {}));
511  GV.addMetadata(LLVMContext::MD_dbg, *DGVE);
512  } else
513  GV.addMetadata(LLVMContext::MD_dbg, *MD);
514  }
515  }
516 
517  /// Remove a leading DW_OP_deref from DIExpressions in a dbg.declare that
518  /// describes a function argument.
519  void upgradeDeclareExpressions(Function &F) {
520  if (!NeedDeclareExpressionUpgrade)
521  return;
522 
523  for (auto &BB : F)
524  for (auto &I : BB)
525  if (auto *DDI = dyn_cast<DbgDeclareInst>(&I))
526  if (auto *DIExpr = DDI->getExpression())
527  if (DIExpr->startsWithDeref() &&
528  dyn_cast_or_null<Argument>(DDI->getAddress())) {
530  Ops.append(std::next(DIExpr->elements_begin()),
531  DIExpr->elements_end());
532  auto *E = DIExpression::get(Context, Ops);
533  DDI->setOperand(2, MetadataAsValue::get(Context, E));
534  }
535  }
536 
537  /// Upgrade the expression from previous versions.
538  Error upgradeDIExpression(uint64_t FromVersion,
540  SmallVectorImpl<uint64_t> &Buffer) {
541  auto N = Expr.size();
542  switch (FromVersion) {
543  default:
544  return error("Invalid record");
545  case 0:
546  if (N >= 3 && Expr[N - 3] == dwarf::DW_OP_bit_piece)
547  Expr[N - 3] = dwarf::DW_OP_LLVM_fragment;
549  case 1:
550  // Move DW_OP_deref to the end.
551  if (N && Expr[0] == dwarf::DW_OP_deref) {
552  auto End = Expr.end();
553  if (Expr.size() >= 3 &&
554  *std::prev(End, 3) == dwarf::DW_OP_LLVM_fragment)
555  End = std::prev(End, 3);
556  std::move(std::next(Expr.begin()), End, Expr.begin());
557  *std::prev(End) = dwarf::DW_OP_deref;
558  }
559  NeedDeclareExpressionUpgrade = true;
561  case 2: {
562  // Change DW_OP_plus to DW_OP_plus_uconst.
563  // Change DW_OP_minus to DW_OP_uconst, DW_OP_minus
564  auto SubExpr = ArrayRef<uint64_t>(Expr);
565  while (!SubExpr.empty()) {
566  // Skip past other operators with their operands
567  // for this version of the IR, obtained from
568  // from historic DIExpression::ExprOperand::getSize().
569  size_t HistoricSize;
570  switch (SubExpr.front()) {
571  default:
572  HistoricSize = 1;
573  break;
574  case dwarf::DW_OP_constu:
575  case dwarf::DW_OP_minus:
576  case dwarf::DW_OP_plus:
577  HistoricSize = 2;
578  break;
580  HistoricSize = 3;
581  break;
582  }
583 
584  // If the expression is malformed, make sure we don't
585  // copy more elements than we should.
586  HistoricSize = std::min(SubExpr.size(), HistoricSize);
587  ArrayRef<uint64_t> Args = SubExpr.slice(1, HistoricSize-1);
588 
589  switch (SubExpr.front()) {
590  case dwarf::DW_OP_plus:
591  Buffer.push_back(dwarf::DW_OP_plus_uconst);
592  Buffer.append(Args.begin(), Args.end());
593  break;
594  case dwarf::DW_OP_minus:
595  Buffer.push_back(dwarf::DW_OP_constu);
596  Buffer.append(Args.begin(), Args.end());
597  Buffer.push_back(dwarf::DW_OP_minus);
598  break;
599  default:
600  Buffer.push_back(*SubExpr.begin());
601  Buffer.append(Args.begin(), Args.end());
602  break;
603  }
604 
605  // Continue with remaining elements.
606  SubExpr = SubExpr.slice(HistoricSize);
607  }
608  Expr = MutableArrayRef<uint64_t>(Buffer);
610  }
611  case 3:
612  // Up-to-date!
613  break;
614  }
615 
616  return Error::success();
617  }
618 
619  void upgradeDebugInfo() {
620  upgradeCUSubprograms();
621  upgradeCUVariables();
622  }
623 
624 public:
626  BitcodeReaderValueList &ValueList,
627  std::function<Type *(unsigned)> getTypeByID,
628  bool IsImporting)
629  : MetadataList(TheModule.getContext()), ValueList(ValueList),
630  Stream(Stream), Context(TheModule.getContext()), TheModule(TheModule),
631  getTypeByID(std::move(getTypeByID)), IsImporting(IsImporting) {}
632 
633  Error parseMetadata(bool ModuleLevel);
634 
635  bool hasFwdRefs() const { return MetadataList.hasFwdRefs(); }
636 
638  if (ID < MDStringRef.size())
639  return lazyLoadOneMDString(ID);
640  if (auto *MD = MetadataList.lookup(ID))
641  return MD;
642  // If lazy-loading is enabled, we try recursively to load the operand
643  // instead of creating a temporary.
644  if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) {
645  PlaceholderQueue Placeholders;
646  lazyLoadOneMetadata(ID, Placeholders);
647  resolveForwardRefsAndPlaceholders(Placeholders);
648  return MetadataList.lookup(ID);
649  }
650  return MetadataList.getMetadataFwdRef(ID);
651  }
652 
653  MDNode *getMDNodeFwdRefOrNull(unsigned Idx) {
654  return MetadataList.getMDNodeFwdRefOrNull(Idx);
655  }
656 
658  return FunctionsWithSPs.lookup(F);
659  }
660 
661  bool hasSeenOldLoopTags() { return HasSeenOldLoopTags; }
662 
663  Error parseMetadataAttachment(
664  Function &F, const SmallVectorImpl<Instruction *> &InstructionList);
665 
666  Error parseMetadataKinds();
667 
668  void setStripTBAA(bool Value) { StripTBAA = Value; }
669  bool isStrippingTBAA() { return StripTBAA; }
670 
671  unsigned size() const { return MetadataList.size(); }
672  void shrinkTo(unsigned N) { MetadataList.shrinkTo(N); }
673  void upgradeDebugIntrinsics(Function &F) { upgradeDeclareExpressions(F); }
674 };
675 
677 MetadataLoader::MetadataLoaderImpl::lazyLoadModuleMetadataBlock() {
678  IndexCursor = Stream;
680  // Get the abbrevs, and preload record positions to make them lazy-loadable.
681  while (true) {
682  BitstreamEntry Entry = IndexCursor.advanceSkippingSubblocks(
684  switch (Entry.Kind) {
685  case BitstreamEntry::SubBlock: // Handled for us already.
687  return error("Malformed block");
689  return true;
690  }
691  case BitstreamEntry::Record: {
692  // The interesting case.
693  ++NumMDRecordLoaded;
694  uint64_t CurrentPos = IndexCursor.GetCurrentBitNo();
695  auto Code = IndexCursor.skipRecord(Entry.ID);
696  switch (Code) {
697  case bitc::METADATA_STRINGS: {
698  // Rewind and parse the strings.
699  IndexCursor.JumpToBit(CurrentPos);
700  StringRef Blob;
701  Record.clear();
702  IndexCursor.readRecord(Entry.ID, Record, &Blob);
703  unsigned NumStrings = Record[0];
704  MDStringRef.reserve(NumStrings);
705  auto IndexNextMDString = [&](StringRef Str) {
706  MDStringRef.push_back(Str);
707  };
708  if (auto Err = parseMetadataStrings(Record, Blob, IndexNextMDString))
709  return std::move(Err);
710  break;
711  }
713  // This is the offset to the index, when we see this we skip all the
714  // records and load only an index to these.
715  IndexCursor.JumpToBit(CurrentPos);
716  Record.clear();
717  IndexCursor.readRecord(Entry.ID, Record);
718  if (Record.size() != 2)
719  return error("Invalid record");
720  auto Offset = Record[0] + (Record[1] << 32);
721  auto BeginPos = IndexCursor.GetCurrentBitNo();
722  IndexCursor.JumpToBit(BeginPos + Offset);
723  Entry = IndexCursor.advanceSkippingSubblocks(
726  "Corrupted bitcode: Expected `Record` when trying to find the "
727  "Metadata index");
728  Record.clear();
729  auto Code = IndexCursor.readRecord(Entry.ID, Record);
730  (void)Code;
731  assert(Code == bitc::METADATA_INDEX && "Corrupted bitcode: Expected "
732  "`METADATA_INDEX` when trying "
733  "to find the Metadata index");
734 
735  // Delta unpack
736  auto CurrentValue = BeginPos;
737  GlobalMetadataBitPosIndex.reserve(Record.size());
738  for (auto &Elt : Record) {
739  CurrentValue += Elt;
740  GlobalMetadataBitPosIndex.push_back(CurrentValue);
741  }
742  break;
743  }
745  // We don't expect to get there, the Index is loaded when we encounter
746  // the offset.
747  return error("Corrupted Metadata block");
748  case bitc::METADATA_NAME: {
749  // Named metadata need to be materialized now and aren't deferred.
750  IndexCursor.JumpToBit(CurrentPos);
751  Record.clear();
752  unsigned Code = IndexCursor.readRecord(Entry.ID, Record);
753  assert(Code == bitc::METADATA_NAME);
754 
755  // Read name of the named metadata.
756  SmallString<8> Name(Record.begin(), Record.end());
757  Code = IndexCursor.ReadCode();
758 
759  // Named Metadata comes in two parts, we expect the name to be followed
760  // by the node
761  Record.clear();
762  unsigned NextBitCode = IndexCursor.readRecord(Code, Record);
763  assert(NextBitCode == bitc::METADATA_NAMED_NODE);
764  (void)NextBitCode;
765 
766  // Read named metadata elements.
767  unsigned Size = Record.size();
768  NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name);
769  for (unsigned i = 0; i != Size; ++i) {
770  // FIXME: We could use a placeholder here, however NamedMDNode are
771  // taking MDNode as operand and not using the Metadata infrastructure.
772  // It is acknowledged by 'TODO: Inherit from Metadata' in the
773  // NamedMDNode class definition.
774  MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]);
775  assert(MD && "Invalid record");
776  NMD->addOperand(MD);
777  }
778  break;
779  }
781  // FIXME: we need to do this early because we don't materialize global
782  // value explicitly.
783  IndexCursor.JumpToBit(CurrentPos);
784  Record.clear();
785  IndexCursor.readRecord(Entry.ID, Record);
786  if (Record.size() % 2 == 0)
787  return error("Invalid record");
788  unsigned ValueID = Record[0];
789  if (ValueID >= ValueList.size())
790  return error("Invalid record");
791  if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID]))
792  if (Error Err = parseGlobalObjectAttachment(
793  *GO, ArrayRef<uint64_t>(Record).slice(1)))
794  return std::move(Err);
795  break;
796  }
797  case bitc::METADATA_KIND:
803  case bitc::METADATA_NODE:
813  case bitc::METADATA_FILE:
830  // We don't expect to see any of these, if we see one, give up on
831  // lazy-loading and fallback.
832  MDStringRef.clear();
833  GlobalMetadataBitPosIndex.clear();
834  return false;
835  }
836  break;
837  }
838  }
839  }
840 }
841 
842 /// Parse a METADATA_BLOCK. If ModuleLevel is true then we are parsing
843 /// module level metadata.
845  if (!ModuleLevel && MetadataList.hasFwdRefs())
846  return error("Invalid metadata: fwd refs into function blocks");
847 
848  // Record the entry position so that we can jump back here and efficiently
849  // skip the whole block in case we lazy-load.
850  auto EntryPos = Stream.GetCurrentBitNo();
851 
853  return error("Invalid record");
854 
856  PlaceholderQueue Placeholders;
857 
858  // We lazy-load module-level metadata: we build an index for each record, and
859  // then load individual record as needed, starting with the named metadata.
860  if (ModuleLevel && IsImporting && MetadataList.empty() &&
862  auto SuccessOrErr = lazyLoadModuleMetadataBlock();
863  if (!SuccessOrErr)
864  return SuccessOrErr.takeError();
865  if (SuccessOrErr.get()) {
866  // An index was successfully created and we will be able to load metadata
867  // on-demand.
868  MetadataList.resize(MDStringRef.size() +
869  GlobalMetadataBitPosIndex.size());
870 
871  // Reading the named metadata created forward references and/or
872  // placeholders, that we flush here.
873  resolveForwardRefsAndPlaceholders(Placeholders);
874  upgradeDebugInfo();
875  // Return at the beginning of the block, since it is easy to skip it
876  // entirely from there.
877  Stream.ReadBlockEnd(); // Pop the abbrev block context.
878  Stream.JumpToBit(EntryPos);
879  if (Stream.SkipBlock())
880  return error("Invalid record");
881  return Error::success();
882  }
883  // Couldn't load an index, fallback to loading all the block "old-style".
884  }
885 
886  unsigned NextMetadataNo = MetadataList.size();
887 
888  // Read all the records.
889  while (true) {
890  BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
891 
892  switch (Entry.Kind) {
893  case BitstreamEntry::SubBlock: // Handled for us already.
895  return error("Malformed block");
897  resolveForwardRefsAndPlaceholders(Placeholders);
898  upgradeDebugInfo();
899  return Error::success();
901  // The interesting case.
902  break;
903  }
904 
905  // Read a record.
906  Record.clear();
907  StringRef Blob;
908  ++NumMDRecordLoaded;
909  unsigned Code = Stream.readRecord(Entry.ID, Record, &Blob);
910  if (Error Err =
911  parseOneMetadata(Record, Code, Placeholders, Blob, NextMetadataNo))
912  return Err;
913  }
914 }
915 
916 MDString *MetadataLoader::MetadataLoaderImpl::lazyLoadOneMDString(unsigned ID) {
917  ++NumMDStringLoaded;
918  if (Metadata *MD = MetadataList.lookup(ID))
919  return cast<MDString>(MD);
920  auto MDS = MDString::get(Context, MDStringRef[ID]);
921  MetadataList.assignValue(MDS, ID);
922  return MDS;
923 }
924 
925 void MetadataLoader::MetadataLoaderImpl::lazyLoadOneMetadata(
926  unsigned ID, PlaceholderQueue &Placeholders) {
927  assert(ID < (MDStringRef.size()) + GlobalMetadataBitPosIndex.size());
928  assert(ID >= MDStringRef.size() && "Unexpected lazy-loading of MDString");
929  // Lookup first if the metadata hasn't already been loaded.
930  if (auto *MD = MetadataList.lookup(ID)) {
931  auto *N = dyn_cast_or_null<MDNode>(MD);
932  if (!N->isTemporary())
933  return;
934  }
936  StringRef Blob;
937  IndexCursor.JumpToBit(GlobalMetadataBitPosIndex[ID - MDStringRef.size()]);
938  auto Entry = IndexCursor.advanceSkippingSubblocks();
939  ++NumMDRecordLoaded;
940  unsigned Code = IndexCursor.readRecord(Entry.ID, Record, &Blob);
941  if (Error Err = parseOneMetadata(Record, Code, Placeholders, Blob, ID))
942  report_fatal_error("Can't lazyload MD");
943 }
944 
945 /// Ensure that all forward-references and placeholders are resolved.
946 /// Iteratively lazy-loading metadata on-demand if needed.
947 void MetadataLoader::MetadataLoaderImpl::resolveForwardRefsAndPlaceholders(
948  PlaceholderQueue &Placeholders) {
949  DenseSet<unsigned> Temporaries;
950  while (1) {
951  // Populate Temporaries with the placeholders that haven't been loaded yet.
952  Placeholders.getTemporaries(MetadataList, Temporaries);
953 
954  // If we don't have any temporary, or FwdReference, we're done!
955  if (Temporaries.empty() && !MetadataList.hasFwdRefs())
956  break;
957 
958  // First, load all the temporaries. This can add new placeholders or
959  // forward references.
960  for (auto ID : Temporaries)
961  lazyLoadOneMetadata(ID, Placeholders);
962  Temporaries.clear();
963 
964  // Second, load the forward-references. This can also add new placeholders
965  // or forward references.
966  while (MetadataList.hasFwdRefs())
967  lazyLoadOneMetadata(MetadataList.getNextFwdRef(), Placeholders);
968  }
969  // At this point we don't have any forward reference remaining, or temporary
970  // that haven't been loaded. We can safely drop RAUW support and mark cycles
971  // as resolved.
972  MetadataList.tryToResolveCycles();
973 
974  // Finally, everything is in place, we can replace the placeholders operands
975  // with the final node they refer to.
976  Placeholders.flush(MetadataList);
977 }
978 
979 Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata(
980  SmallVectorImpl<uint64_t> &Record, unsigned Code,
981  PlaceholderQueue &Placeholders, StringRef Blob, unsigned &NextMetadataNo) {
982 
983  bool IsDistinct = false;
984  auto getMD = [&](unsigned ID) -> Metadata * {
985  if (ID < MDStringRef.size())
986  return lazyLoadOneMDString(ID);
987  if (!IsDistinct) {
988  if (auto *MD = MetadataList.lookup(ID))
989  return MD;
990  // If lazy-loading is enabled, we try recursively to load the operand
991  // instead of creating a temporary.
992  if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) {
993  // Create a temporary for the node that is referencing the operand we
994  // will lazy-load. It is needed before recursing in case there are
995  // uniquing cycles.
996  MetadataList.getMetadataFwdRef(NextMetadataNo);
997  lazyLoadOneMetadata(ID, Placeholders);
998  return MetadataList.lookup(ID);
999  }
1000  // Return a temporary.
1001  return MetadataList.getMetadataFwdRef(ID);
1002  }
1003  if (auto *MD = MetadataList.getMetadataIfResolved(ID))
1004  return MD;
1005  return &Placeholders.getPlaceholderOp(ID);
1006  };
1007  auto getMDOrNull = [&](unsigned ID) -> Metadata * {
1008  if (ID)
1009  return getMD(ID - 1);
1010  return nullptr;
1011  };
1012  auto getMDOrNullWithoutPlaceholders = [&](unsigned ID) -> Metadata * {
1013  if (ID)
1014  return MetadataList.getMetadataFwdRef(ID - 1);
1015  return nullptr;
1016  };
1017  auto getMDString = [&](unsigned ID) -> MDString * {
1018  // This requires that the ID is not really a forward reference. In
1019  // particular, the MDString must already have been resolved.
1020  auto MDS = getMDOrNull(ID);
1021  return cast_or_null<MDString>(MDS);
1022  };
1023 
1024  // Support for old type refs.
1025  auto getDITypeRefOrNull = [&](unsigned ID) {
1026  return MetadataList.upgradeTypeRef(getMDOrNull(ID));
1027  };
1028 
1029 #define GET_OR_DISTINCT(CLASS, ARGS) \
1030  (IsDistinct ? CLASS::getDistinct ARGS : CLASS::get ARGS)
1031 
1032  switch (Code) {
1033  default: // Default behavior: ignore.
1034  break;
1035  case bitc::METADATA_NAME: {
1036  // Read name of the named metadata.
1037  SmallString<8> Name(Record.begin(), Record.end());
1038  Record.clear();
1039  Code = Stream.ReadCode();
1040 
1041  ++NumMDRecordLoaded;
1042  unsigned NextBitCode = Stream.readRecord(Code, Record);
1043  if (NextBitCode != bitc::METADATA_NAMED_NODE)
1044  return error("METADATA_NAME not followed by METADATA_NAMED_NODE");
1045 
1046  // Read named metadata elements.
1047  unsigned Size = Record.size();
1048  NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name);
1049  for (unsigned i = 0; i != Size; ++i) {
1050  MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]);
1051  if (!MD)
1052  return error("Invalid record");
1053  NMD->addOperand(MD);
1054  }
1055  break;
1056  }
1058  // FIXME: Remove in 4.0.
1059  // This is a LocalAsMetadata record, the only type of function-local
1060  // metadata.
1061  if (Record.size() % 2 == 1)
1062  return error("Invalid record");
1063 
1064  // If this isn't a LocalAsMetadata record, we're dropping it. This used
1065  // to be legal, but there's no upgrade path.
1066  auto dropRecord = [&] {
1067  MetadataList.assignValue(MDNode::get(Context, None), NextMetadataNo);
1068  NextMetadataNo++;
1069  };
1070  if (Record.size() != 2) {
1071  dropRecord();
1072  break;
1073  }
1074 
1075  Type *Ty = getTypeByID(Record[0]);
1076  if (Ty->isMetadataTy() || Ty->isVoidTy()) {
1077  dropRecord();
1078  break;
1079  }
1080 
1081  MetadataList.assignValue(
1082  LocalAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)),
1083  NextMetadataNo);
1084  NextMetadataNo++;
1085  break;
1086  }
1087  case bitc::METADATA_OLD_NODE: {
1088  // FIXME: Remove in 4.0.
1089  if (Record.size() % 2 == 1)
1090  return error("Invalid record");
1091 
1092  unsigned Size = Record.size();
1094  for (unsigned i = 0; i != Size; i += 2) {
1095  Type *Ty = getTypeByID(Record[i]);
1096  if (!Ty)
1097  return error("Invalid record");
1098  if (Ty->isMetadataTy())
1099  Elts.push_back(getMD(Record[i + 1]));
1100  else if (!Ty->isVoidTy()) {
1101  auto *MD =
1102  ValueAsMetadata::get(ValueList.getValueFwdRef(Record[i + 1], Ty));
1103  assert(isa<ConstantAsMetadata>(MD) &&
1104  "Expected non-function-local metadata");
1105  Elts.push_back(MD);
1106  } else
1107  Elts.push_back(nullptr);
1108  }
1109  MetadataList.assignValue(MDNode::get(Context, Elts), NextMetadataNo);
1110  NextMetadataNo++;
1111  break;
1112  }
1113  case bitc::METADATA_VALUE: {
1114  if (Record.size() != 2)
1115  return error("Invalid record");
1116 
1117  Type *Ty = getTypeByID(Record[0]);
1118  if (Ty->isMetadataTy() || Ty->isVoidTy())
1119  return error("Invalid record");
1120 
1121  MetadataList.assignValue(
1122  ValueAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)),
1123  NextMetadataNo);
1124  NextMetadataNo++;
1125  break;
1126  }
1128  IsDistinct = true;
1130  case bitc::METADATA_NODE: {
1132  Elts.reserve(Record.size());
1133  for (unsigned ID : Record)
1134  Elts.push_back(getMDOrNull(ID));
1135  MetadataList.assignValue(IsDistinct ? MDNode::getDistinct(Context, Elts)
1136  : MDNode::get(Context, Elts),
1137  NextMetadataNo);
1138  NextMetadataNo++;
1139  break;
1140  }
1141  case bitc::METADATA_LOCATION: {
1142  if (Record.size() != 5 && Record.size() != 6)
1143  return error("Invalid record");
1144 
1145  IsDistinct = Record[0];
1146  unsigned Line = Record[1];
1147  unsigned Column = Record[2];
1148  Metadata *Scope = getMD(Record[3]);
1149  Metadata *InlinedAt = getMDOrNull(Record[4]);
1150  bool ImplicitCode = Record.size() == 6 && Record[5];
1151  MetadataList.assignValue(
1152  GET_OR_DISTINCT(DILocation, (Context, Line, Column, Scope, InlinedAt,
1153  ImplicitCode)),
1154  NextMetadataNo);
1155  NextMetadataNo++;
1156  break;
1157  }
1159  if (Record.size() < 4)
1160  return error("Invalid record");
1161 
1162  IsDistinct = Record[0];
1163  unsigned Tag = Record[1];
1164  unsigned Version = Record[2];
1165 
1166  if (Tag >= 1u << 16 || Version != 0)
1167  return error("Invalid record");
1168 
1169  auto *Header = getMDString(Record[3]);
1170  SmallVector<Metadata *, 8> DwarfOps;
1171  for (unsigned I = 4, E = Record.size(); I != E; ++I)
1172  DwarfOps.push_back(getMDOrNull(Record[I]));
1173  MetadataList.assignValue(
1174  GET_OR_DISTINCT(GenericDINode, (Context, Tag, Header, DwarfOps)),
1175  NextMetadataNo);
1176  NextMetadataNo++;
1177  break;
1178  }
1179  case bitc::METADATA_SUBRANGE: {
1180  Metadata *Val = nullptr;
1181  // Operand 'count' is interpreted as:
1182  // - Signed integer (version 0)
1183  // - Metadata node (version 1)
1184  switch (Record[0] >> 1) {
1185  case 0:
1187  (Context, Record[1], unrotateSign(Record.back())));
1188  break;
1189  case 1:
1190  Val = GET_OR_DISTINCT(DISubrange, (Context, getMDOrNull(Record[1]),
1191  unrotateSign(Record.back())));
1192  break;
1193  default:
1194  return error("Invalid record: Unsupported version of DISubrange");
1195  }
1196 
1197  MetadataList.assignValue(Val, NextMetadataNo);
1198  IsDistinct = Record[0] & 1;
1199  NextMetadataNo++;
1200  break;
1201  }
1203  if (Record.size() != 3)
1204  return error("Invalid record");
1205 
1206  IsDistinct = Record[0] & 1;
1207  bool IsUnsigned = Record[0] & 2;
1208  MetadataList.assignValue(
1209  GET_OR_DISTINCT(DIEnumerator, (Context, unrotateSign(Record[1]),
1210  IsUnsigned, getMDString(Record[2]))),
1211  NextMetadataNo);
1212  NextMetadataNo++;
1213  break;
1214  }
1216  if (Record.size() < 6 || Record.size() > 7)
1217  return error("Invalid record");
1218 
1219  IsDistinct = Record[0];
1220  DINode::DIFlags Flags = (Record.size() > 6) ?
1221  static_cast<DINode::DIFlags>(Record[6]) : DINode::FlagZero;
1222 
1223  MetadataList.assignValue(
1225  (Context, Record[1], getMDString(Record[2]), Record[3],
1226  Record[4], Record[5], Flags)),
1227  NextMetadataNo);
1228  NextMetadataNo++;
1229  break;
1230  }
1232  if (Record.size() < 12 || Record.size() > 13)
1233  return error("Invalid record");
1234 
1235  // DWARF address space is encoded as N->getDWARFAddressSpace() + 1. 0 means
1236  // that there is no DWARF address space associated with DIDerivedType.
1237  Optional<unsigned> DWARFAddressSpace;
1238  if (Record.size() > 12 && Record[12])
1239  DWARFAddressSpace = Record[12] - 1;
1240 
1241  IsDistinct = Record[0];
1242  DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]);
1243  MetadataList.assignValue(
1245  (Context, Record[1], getMDString(Record[2]),
1246  getMDOrNull(Record[3]), Record[4],
1247  getDITypeRefOrNull(Record[5]),
1248  getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1249  Record[9], DWARFAddressSpace, Flags,
1250  getDITypeRefOrNull(Record[11]))),
1251  NextMetadataNo);
1252  NextMetadataNo++;
1253  break;
1254  }
1256  if (Record.size() < 16 || Record.size() > 17)
1257  return error("Invalid record");
1258 
1259  // If we have a UUID and this is not a forward declaration, lookup the
1260  // mapping.
1261  IsDistinct = Record[0] & 0x1;
1262  bool IsNotUsedInTypeRef = Record[0] >= 2;
1263  unsigned Tag = Record[1];
1264  MDString *Name = getMDString(Record[2]);
1265  Metadata *File = getMDOrNull(Record[3]);
1266  unsigned Line = Record[4];
1267  Metadata *Scope = getDITypeRefOrNull(Record[5]);
1268  Metadata *BaseType = nullptr;
1269  uint64_t SizeInBits = Record[7];
1270  if (Record[8] > (uint64_t)std::numeric_limits<uint32_t>::max())
1271  return error("Alignment value is too large");
1272  uint32_t AlignInBits = Record[8];
1273  uint64_t OffsetInBits = 0;
1274  DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]);
1275  Metadata *Elements = nullptr;
1276  unsigned RuntimeLang = Record[12];
1277  Metadata *VTableHolder = nullptr;
1278  Metadata *TemplateParams = nullptr;
1279  Metadata *Discriminator = nullptr;
1280  auto *Identifier = getMDString(Record[15]);
1281  // If this module is being parsed so that it can be ThinLTO imported
1282  // into another module, composite types only need to be imported
1283  // as type declarations (unless full type definitions requested).
1284  // Create type declarations up front to save memory. Also, buildODRType
1285  // handles the case where this is type ODRed with a definition needed
1286  // by the importing module, in which case the existing definition is
1287  // used.
1288  if (IsImporting && !ImportFullTypeDefinitions && Identifier &&
1289  (Tag == dwarf::DW_TAG_enumeration_type ||
1290  Tag == dwarf::DW_TAG_class_type ||
1291  Tag == dwarf::DW_TAG_structure_type ||
1292  Tag == dwarf::DW_TAG_union_type)) {
1293  Flags = Flags | DINode::FlagFwdDecl;
1294  } else {
1295  BaseType = getDITypeRefOrNull(Record[6]);
1296  OffsetInBits = Record[9];
1297  Elements = getMDOrNull(Record[11]);
1298  VTableHolder = getDITypeRefOrNull(Record[13]);
1299  TemplateParams = getMDOrNull(Record[14]);
1300  if (Record.size() > 16)
1301  Discriminator = getMDOrNull(Record[16]);
1302  }
1303  DICompositeType *CT = nullptr;
1304  if (Identifier)
1306  Context, *Identifier, Tag, Name, File, Line, Scope, BaseType,
1307  SizeInBits, AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
1308  VTableHolder, TemplateParams, Discriminator);
1309 
1310  // Create a node if we didn't get a lazy ODR type.
1311  if (!CT)
1313  (Context, Tag, Name, File, Line, Scope, BaseType,
1314  SizeInBits, AlignInBits, OffsetInBits, Flags,
1315  Elements, RuntimeLang, VTableHolder, TemplateParams,
1316  Identifier, Discriminator));
1317  if (!IsNotUsedInTypeRef && Identifier)
1318  MetadataList.addTypeRef(*Identifier, *cast<DICompositeType>(CT));
1319 
1320  MetadataList.assignValue(CT, NextMetadataNo);
1321  NextMetadataNo++;
1322  break;
1323  }
1325  if (Record.size() < 3 || Record.size() > 4)
1326  return error("Invalid record");
1327  bool IsOldTypeRefArray = Record[0] < 2;
1328  unsigned CC = (Record.size() > 3) ? Record[3] : 0;
1329 
1330  IsDistinct = Record[0] & 0x1;
1331  DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[1]);
1332  Metadata *Types = getMDOrNull(Record[2]);
1333  if (LLVM_UNLIKELY(IsOldTypeRefArray))
1334  Types = MetadataList.upgradeTypeRefArray(Types);
1335 
1336  MetadataList.assignValue(
1337  GET_OR_DISTINCT(DISubroutineType, (Context, Flags, CC, Types)),
1338  NextMetadataNo);
1339  NextMetadataNo++;
1340  break;
1341  }
1342 
1343  case bitc::METADATA_MODULE: {
1344  if (Record.size() != 6)
1345  return error("Invalid record");
1346 
1347  IsDistinct = Record[0];
1348  MetadataList.assignValue(
1350  (Context, getMDOrNull(Record[1]),
1351  getMDString(Record[2]), getMDString(Record[3]),
1352  getMDString(Record[4]), getMDString(Record[5]))),
1353  NextMetadataNo);
1354  NextMetadataNo++;
1355  break;
1356  }
1357 
1358  case bitc::METADATA_FILE: {
1359  if (Record.size() != 3 && Record.size() != 5 && Record.size() != 6)
1360  return error("Invalid record");
1361 
1362  IsDistinct = Record[0];
1364  // The BitcodeWriter writes null bytes into Record[3:4] when the Checksum
1365  // is not present. This matches up with the old internal representation,
1366  // and the old encoding for CSK_None in the ChecksumKind. The new
1367  // representation reserves the value 0 in the ChecksumKind to continue to
1368  // encode None in a backwards-compatible way.
1369  if (Record.size() > 4 && Record[3] && Record[4])
1370  Checksum.emplace(static_cast<DIFile::ChecksumKind>(Record[3]),
1371  getMDString(Record[4]));
1372  MetadataList.assignValue(
1374  DIFile,
1375  (Context, getMDString(Record[1]), getMDString(Record[2]), Checksum,
1376  Record.size() > 5 ? Optional<MDString *>(getMDString(Record[5]))
1377  : None)),
1378  NextMetadataNo);
1379  NextMetadataNo++;
1380  break;
1381  }
1383  if (Record.size() < 14 || Record.size() > 19)
1384  return error("Invalid record");
1385 
1386  // Ignore Record[0], which indicates whether this compile unit is
1387  // distinct. It's always distinct.
1388  IsDistinct = true;
1390  Context, Record[1], getMDOrNull(Record[2]), getMDString(Record[3]),
1391  Record[4], getMDString(Record[5]), Record[6], getMDString(Record[7]),
1392  Record[8], getMDOrNull(Record[9]), getMDOrNull(Record[10]),
1393  getMDOrNull(Record[12]), getMDOrNull(Record[13]),
1394  Record.size() <= 15 ? nullptr : getMDOrNull(Record[15]),
1395  Record.size() <= 14 ? 0 : Record[14],
1396  Record.size() <= 16 ? true : Record[16],
1397  Record.size() <= 17 ? false : Record[17],
1398  Record.size() <= 18 ? 0 : Record[18]);
1399 
1400  MetadataList.assignValue(CU, NextMetadataNo);
1401  NextMetadataNo++;
1402 
1403  // Move the Upgrade the list of subprograms.
1404  if (Metadata *SPs = getMDOrNullWithoutPlaceholders(Record[11]))
1405  CUSubprograms.push_back({CU, SPs});
1406  break;
1407  }
1409  if (Record.size() < 18 || Record.size() > 21)
1410  return error("Invalid record");
1411 
1412  IsDistinct =
1413  (Record[0] & 1) || Record[8]; // All definitions should be distinct.
1414  // Version 1 has a Function as Record[15].
1415  // Version 2 has removed Record[15].
1416  // Version 3 has the Unit as Record[15].
1417  // Version 4 added thisAdjustment.
1418  bool HasUnit = Record[0] >= 2;
1419  if (HasUnit && Record.size() < 19)
1420  return error("Invalid record");
1421  Metadata *CUorFn = getMDOrNull(Record[15]);
1422  unsigned Offset = Record.size() >= 19 ? 1 : 0;
1423  bool HasFn = Offset && !HasUnit;
1424  bool HasThisAdj = Record.size() >= 20;
1425  bool HasThrownTypes = Record.size() >= 21;
1427  DISubprogram,
1428  (Context,
1429  getDITypeRefOrNull(Record[1]), // scope
1430  getMDString(Record[2]), // name
1431  getMDString(Record[3]), // linkageName
1432  getMDOrNull(Record[4]), // file
1433  Record[5], // line
1434  getMDOrNull(Record[6]), // type
1435  Record[7], // isLocal
1436  Record[8], // isDefinition
1437  Record[9], // scopeLine
1438  getDITypeRefOrNull(Record[10]), // containingType
1439  Record[11], // virtuality
1440  Record[12], // virtualIndex
1441  HasThisAdj ? Record[19] : 0, // thisAdjustment
1442  static_cast<DINode::DIFlags>(Record[13]), // flags
1443  Record[14], // isOptimized
1444  HasUnit ? CUorFn : nullptr, // unit
1445  getMDOrNull(Record[15 + Offset]), // templateParams
1446  getMDOrNull(Record[16 + Offset]), // declaration
1447  getMDOrNull(Record[17 + Offset]), // retainedNodes
1448  HasThrownTypes ? getMDOrNull(Record[20]) : nullptr // thrownTypes
1449  ));
1450  MetadataList.assignValue(SP, NextMetadataNo);
1451  NextMetadataNo++;
1452 
1453  // Upgrade sp->function mapping to function->sp mapping.
1454  if (HasFn) {
1455  if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(CUorFn))
1456  if (auto *F = dyn_cast<Function>(CMD->getValue())) {
1457  if (F->isMaterializable())
1458  // Defer until materialized; unmaterialized functions may not have
1459  // metadata.
1460  FunctionsWithSPs[F] = SP;
1461  else if (!F->empty())
1462  F->setSubprogram(SP);
1463  }
1464  }
1465  break;
1466  }
1468  if (Record.size() != 5)
1469  return error("Invalid record");
1470 
1471  IsDistinct = Record[0];
1472  MetadataList.assignValue(
1474  (Context, getMDOrNull(Record[1]),
1475  getMDOrNull(Record[2]), Record[3], Record[4])),
1476  NextMetadataNo);
1477  NextMetadataNo++;
1478  break;
1479  }
1481  if (Record.size() != 4)
1482  return error("Invalid record");
1483 
1484  IsDistinct = Record[0];
1485  MetadataList.assignValue(
1487  (Context, getMDOrNull(Record[1]),
1488  getMDOrNull(Record[2]), Record[3])),
1489  NextMetadataNo);
1490  NextMetadataNo++;
1491  break;
1492  }
1493  case bitc::METADATA_NAMESPACE: {
1494  // Newer versions of DINamespace dropped file and line.
1495  MDString *Name;
1496  if (Record.size() == 3)
1497  Name = getMDString(Record[2]);
1498  else if (Record.size() == 5)
1499  Name = getMDString(Record[3]);
1500  else
1501  return error("Invalid record");
1502 
1503  IsDistinct = Record[0] & 1;
1504  bool ExportSymbols = Record[0] & 2;
1505  MetadataList.assignValue(
1507  (Context, getMDOrNull(Record[1]), Name, ExportSymbols)),
1508  NextMetadataNo);
1509  NextMetadataNo++;
1510  break;
1511  }
1512  case bitc::METADATA_MACRO: {
1513  if (Record.size() != 5)
1514  return error("Invalid record");
1515 
1516  IsDistinct = Record[0];
1517  MetadataList.assignValue(
1519  (Context, Record[1], Record[2], getMDString(Record[3]),
1520  getMDString(Record[4]))),
1521  NextMetadataNo);
1522  NextMetadataNo++;
1523  break;
1524  }
1526  if (Record.size() != 5)
1527  return error("Invalid record");
1528 
1529  IsDistinct = Record[0];
1530  MetadataList.assignValue(
1532  (Context, Record[1], Record[2], getMDOrNull(Record[3]),
1533  getMDOrNull(Record[4]))),
1534  NextMetadataNo);
1535  NextMetadataNo++;
1536  break;
1537  }
1539  if (Record.size() != 3)
1540  return error("Invalid record");
1541 
1542  IsDistinct = Record[0];
1543  MetadataList.assignValue(GET_OR_DISTINCT(DITemplateTypeParameter,
1544  (Context, getMDString(Record[1]),
1545  getDITypeRefOrNull(Record[2]))),
1546  NextMetadataNo);
1547  NextMetadataNo++;
1548  break;
1549  }
1551  if (Record.size() != 5)
1552  return error("Invalid record");
1553 
1554  IsDistinct = Record[0];
1555  MetadataList.assignValue(
1557  (Context, Record[1], getMDString(Record[2]),
1558  getDITypeRefOrNull(Record[3]),
1559  getMDOrNull(Record[4]))),
1560  NextMetadataNo);
1561  NextMetadataNo++;
1562  break;
1563  }
1565  if (Record.size() < 11 || Record.size() > 13)
1566  return error("Invalid record");
1567 
1568  IsDistinct = Record[0] & 1;
1569  unsigned Version = Record[0] >> 1;
1570 
1571  if (Version == 2) {
1572  MetadataList.assignValue(
1575  (Context, getMDOrNull(Record[1]), getMDString(Record[2]),
1576  getMDString(Record[3]), getMDOrNull(Record[4]), Record[5],
1577  getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1578  getMDOrNull(Record[9]), getMDOrNull(Record[10]), Record[11])),
1579  NextMetadataNo);
1580 
1581  NextMetadataNo++;
1582  } else if (Version == 1) {
1583  // No upgrade necessary. A null field will be introduced to indicate
1584  // that no parameter information is available.
1585  MetadataList.assignValue(
1587  (Context, getMDOrNull(Record[1]),
1588  getMDString(Record[2]), getMDString(Record[3]),
1589  getMDOrNull(Record[4]), Record[5],
1590  getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1591  getMDOrNull(Record[10]), nullptr, Record[11])),
1592  NextMetadataNo);
1593 
1594  NextMetadataNo++;
1595  } else if (Version == 0) {
1596  // Upgrade old metadata, which stored a global variable reference or a
1597  // ConstantInt here.
1598  NeedUpgradeToDIGlobalVariableExpression = true;
1599  Metadata *Expr = getMDOrNull(Record[9]);
1600  uint32_t AlignInBits = 0;
1601  if (Record.size() > 11) {
1602  if (Record[11] > (uint64_t)std::numeric_limits<uint32_t>::max())
1603  return error("Alignment value is too large");
1604  AlignInBits = Record[11];
1605  }
1606  GlobalVariable *Attach = nullptr;
1607  if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(Expr)) {
1608  if (auto *GV = dyn_cast<GlobalVariable>(CMD->getValue())) {
1609  Attach = GV;
1610  Expr = nullptr;
1611  } else if (auto *CI = dyn_cast<ConstantInt>(CMD->getValue())) {
1612  Expr = DIExpression::get(Context,
1613  {dwarf::DW_OP_constu, CI->getZExtValue(),
1614  dwarf::DW_OP_stack_value});
1615  } else {
1616  Expr = nullptr;
1617  }
1618  }
1621  (Context, getMDOrNull(Record[1]), getMDString(Record[2]),
1622  getMDString(Record[3]), getMDOrNull(Record[4]), Record[5],
1623  getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1624  getMDOrNull(Record[10]), nullptr, AlignInBits));
1625 
1626  DIGlobalVariableExpression *DGVE = nullptr;
1627  if (Attach || Expr)
1629  Context, DGV, Expr ? Expr : DIExpression::get(Context, {}));
1630  if (Attach)
1631  Attach->addDebugInfo(DGVE);
1632 
1633  auto *MDNode = Expr ? cast<Metadata>(DGVE) : cast<Metadata>(DGV);
1634  MetadataList.assignValue(MDNode, NextMetadataNo);
1635  NextMetadataNo++;
1636  } else
1637  return error("Invalid record");
1638 
1639  break;
1640  }
1641  case bitc::METADATA_LOCAL_VAR: {
1642  // 10th field is for the obseleted 'inlinedAt:' field.
1643  if (Record.size() < 8 || Record.size() > 10)
1644  return error("Invalid record");
1645 
1646  IsDistinct = Record[0] & 1;
1647  bool HasAlignment = Record[0] & 2;
1648  // 2nd field used to be an artificial tag, either DW_TAG_auto_variable or
1649  // DW_TAG_arg_variable, if we have alignment flag encoded it means, that
1650  // this is newer version of record which doesn't have artificial tag.
1651  bool HasTag = !HasAlignment && Record.size() > 8;
1652  DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[7 + HasTag]);
1653  uint32_t AlignInBits = 0;
1654  if (HasAlignment) {
1655  if (Record[8 + HasTag] > (uint64_t)std::numeric_limits<uint32_t>::max())
1656  return error("Alignment value is too large");
1657  AlignInBits = Record[8 + HasTag];
1658  }
1659  MetadataList.assignValue(
1661  (Context, getMDOrNull(Record[1 + HasTag]),
1662  getMDString(Record[2 + HasTag]),
1663  getMDOrNull(Record[3 + HasTag]), Record[4 + HasTag],
1664  getDITypeRefOrNull(Record[5 + HasTag]),
1665  Record[6 + HasTag], Flags, AlignInBits)),
1666  NextMetadataNo);
1667  NextMetadataNo++;
1668  break;
1669  }
1670  case bitc::METADATA_LABEL: {
1671  if (Record.size() != 5)
1672  return error("Invalid record");
1673 
1674  IsDistinct = Record[0] & 1;
1675  MetadataList.assignValue(
1677  (Context, getMDOrNull(Record[1]),
1678  getMDString(Record[2]),
1679  getMDOrNull(Record[3]), Record[4])),
1680  NextMetadataNo);
1681  NextMetadataNo++;
1682  break;
1683  }
1685  if (Record.size() < 1)
1686  return error("Invalid record");
1687 
1688  IsDistinct = Record[0] & 1;
1689  uint64_t Version = Record[0] >> 1;
1690  auto Elts = MutableArrayRef<uint64_t>(Record).slice(1);
1691 
1692  SmallVector<uint64_t, 6> Buffer;
1693  if (Error Err = upgradeDIExpression(Version, Elts, Buffer))
1694  return Err;
1695 
1696  MetadataList.assignValue(
1697  GET_OR_DISTINCT(DIExpression, (Context, Elts)), NextMetadataNo);
1698  NextMetadataNo++;
1699  break;
1700  }
1702  if (Record.size() != 3)
1703  return error("Invalid record");
1704 
1705  IsDistinct = Record[0];
1706  Metadata *Expr = getMDOrNull(Record[2]);
1707  if (!Expr)
1708  Expr = DIExpression::get(Context, {});
1709  MetadataList.assignValue(
1711  (Context, getMDOrNull(Record[1]), Expr)),
1712  NextMetadataNo);
1713  NextMetadataNo++;
1714  break;
1715  }
1717  if (Record.size() != 8)
1718  return error("Invalid record");
1719 
1720  IsDistinct = Record[0];
1721  MetadataList.assignValue(
1723  (Context, getMDString(Record[1]),
1724  getMDOrNull(Record[2]), Record[3],
1725  getMDString(Record[4]), getMDString(Record[5]),
1726  Record[6], getDITypeRefOrNull(Record[7]))),
1727  NextMetadataNo);
1728  NextMetadataNo++;
1729  break;
1730  }
1732  if (Record.size() != 6 && Record.size() != 7)
1733  return error("Invalid record");
1734 
1735  IsDistinct = Record[0];
1736  bool HasFile = (Record.size() == 7);
1737  MetadataList.assignValue(
1739  (Context, Record[1], getMDOrNull(Record[2]),
1740  getDITypeRefOrNull(Record[3]),
1741  HasFile ? getMDOrNull(Record[6]) : nullptr,
1742  HasFile ? Record[4] : 0, getMDString(Record[5]))),
1743  NextMetadataNo);
1744  NextMetadataNo++;
1745  break;
1746  }
1748  std::string String(Record.begin(), Record.end());
1749 
1750  // Test for upgrading !llvm.loop.
1751  HasSeenOldLoopTags |= mayBeOldLoopAttachmentTag(String);
1752  ++NumMDStringLoaded;
1753  Metadata *MD = MDString::get(Context, String);
1754  MetadataList.assignValue(MD, NextMetadataNo);
1755  NextMetadataNo++;
1756  break;
1757  }
1758  case bitc::METADATA_STRINGS: {
1759  auto CreateNextMDString = [&](StringRef Str) {
1760  ++NumMDStringLoaded;
1761  MetadataList.assignValue(MDString::get(Context, Str), NextMetadataNo);
1762  NextMetadataNo++;
1763  };
1764  if (Error Err = parseMetadataStrings(Record, Blob, CreateNextMDString))
1765  return Err;
1766  break;
1767  }
1769  if (Record.size() % 2 == 0)
1770  return error("Invalid record");
1771  unsigned ValueID = Record[0];
1772  if (ValueID >= ValueList.size())
1773  return error("Invalid record");
1774  if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID]))
1775  if (Error Err = parseGlobalObjectAttachment(
1776  *GO, ArrayRef<uint64_t>(Record).slice(1)))
1777  return Err;
1778  break;
1779  }
1780  case bitc::METADATA_KIND: {
1781  // Support older bitcode files that had METADATA_KIND records in a
1782  // block with METADATA_BLOCK_ID.
1783  if (Error Err = parseMetadataKindRecord(Record))
1784  return Err;
1785  break;
1786  }
1787  }
1788  return Error::success();
1789 #undef GET_OR_DISTINCT
1790 }
1791 
1792 Error MetadataLoader::MetadataLoaderImpl::parseMetadataStrings(
1793  ArrayRef<uint64_t> Record, StringRef Blob,
1794  function_ref<void(StringRef)> CallBack) {
1795  // All the MDStrings in the block are emitted together in a single
1796  // record. The strings are concatenated and stored in a blob along with
1797  // their sizes.
1798  if (Record.size() != 2)
1799  return error("Invalid record: metadata strings layout");
1800 
1801  unsigned NumStrings = Record[0];
1802  unsigned StringsOffset = Record[1];
1803  if (!NumStrings)
1804  return error("Invalid record: metadata strings with no strings");
1805  if (StringsOffset > Blob.size())
1806  return error("Invalid record: metadata strings corrupt offset");
1807 
1808  StringRef Lengths = Blob.slice(0, StringsOffset);
1809  SimpleBitstreamCursor R(Lengths);
1810 
1811  StringRef Strings = Blob.drop_front(StringsOffset);
1812  do {
1813  if (R.AtEndOfStream())
1814  return error("Invalid record: metadata strings bad length");
1815 
1816  unsigned Size = R.ReadVBR(6);
1817  if (Strings.size() < Size)
1818  return error("Invalid record: metadata strings truncated chars");
1819 
1820  CallBack(Strings.slice(0, Size));
1821  Strings = Strings.drop_front(Size);
1822  } while (--NumStrings);
1823 
1824  return Error::success();
1825 }
1826 
1827 Error MetadataLoader::MetadataLoaderImpl::parseGlobalObjectAttachment(
1828  GlobalObject &GO, ArrayRef<uint64_t> Record) {
1829  assert(Record.size() % 2 == 0);
1830  for (unsigned I = 0, E = Record.size(); I != E; I += 2) {
1831  auto K = MDKindMap.find(Record[I]);
1832  if (K == MDKindMap.end())
1833  return error("Invalid ID");
1834  MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[I + 1]);
1835  if (!MD)
1836  return error("Invalid metadata attachment");
1837  GO.addMetadata(K->second, *MD);
1838  }
1839  return Error::success();
1840 }
1841 
1842 /// Parse metadata attachments.
1844  Function &F, const SmallVectorImpl<Instruction *> &InstructionList) {
1846  return error("Invalid record");
1847 
1849  PlaceholderQueue Placeholders;
1850 
1851  while (true) {
1852  BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
1853 
1854  switch (Entry.Kind) {
1855  case BitstreamEntry::SubBlock: // Handled for us already.
1856  case BitstreamEntry::Error:
1857  return error("Malformed block");
1859  resolveForwardRefsAndPlaceholders(Placeholders);
1860  return Error::success();
1862  // The interesting case.
1863  break;
1864  }
1865 
1866  // Read a metadata attachment record.
1867  Record.clear();
1868  ++NumMDRecordLoaded;
1869  switch (Stream.readRecord(Entry.ID, Record)) {
1870  default: // Default behavior: ignore.
1871  break;
1873  unsigned RecordLength = Record.size();
1874  if (Record.empty())
1875  return error("Invalid record");
1876  if (RecordLength % 2 == 0) {
1877  // A function attachment.
1878  if (Error Err = parseGlobalObjectAttachment(F, Record))
1879  return Err;
1880  continue;
1881  }
1882 
1883  // An instruction attachment.
1884  Instruction *Inst = InstructionList[Record[0]];
1885  for (unsigned i = 1; i != RecordLength; i = i + 2) {
1886  unsigned Kind = Record[i];
1887  DenseMap<unsigned, unsigned>::iterator I = MDKindMap.find(Kind);
1888  if (I == MDKindMap.end())
1889  return error("Invalid ID");
1890  if (I->second == LLVMContext::MD_tbaa && StripTBAA)
1891  continue;
1892 
1893  auto Idx = Record[i + 1];
1894  if (Idx < (MDStringRef.size() + GlobalMetadataBitPosIndex.size()) &&
1895  !MetadataList.lookup(Idx)) {
1896  // Load the attachment if it is in the lazy-loadable range and hasn't
1897  // been loaded yet.
1898  lazyLoadOneMetadata(Idx, Placeholders);
1899  resolveForwardRefsAndPlaceholders(Placeholders);
1900  }
1901 
1902  Metadata *Node = MetadataList.getMetadataFwdRef(Idx);
1903  if (isa<LocalAsMetadata>(Node))
1904  // Drop the attachment. This used to be legal, but there's no
1905  // upgrade path.
1906  break;
1907  MDNode *MD = dyn_cast_or_null<MDNode>(Node);
1908  if (!MD)
1909  return error("Invalid metadata attachment");
1910 
1911  if (HasSeenOldLoopTags && I->second == LLVMContext::MD_loop)
1913 
1914  if (I->second == LLVMContext::MD_tbaa) {
1915  assert(!MD->isTemporary() && "should load MDs before attachments");
1916  MD = UpgradeTBAANode(*MD);
1917  }
1918  Inst->setMetadata(I->second, MD);
1919  }
1920  break;
1921  }
1922  }
1923  }
1924 }
1925 
1926 /// Parse a single METADATA_KIND record, inserting result in MDKindMap.
1927 Error MetadataLoader::MetadataLoaderImpl::parseMetadataKindRecord(
1928  SmallVectorImpl<uint64_t> &Record) {
1929  if (Record.size() < 2)
1930  return error("Invalid record");
1931 
1932  unsigned Kind = Record[0];
1933  SmallString<8> Name(Record.begin() + 1, Record.end());
1934 
1935  unsigned NewKind = TheModule.getMDKindID(Name.str());
1936  if (!MDKindMap.insert(std::make_pair(Kind, NewKind)).second)
1937  return error("Conflicting METADATA_KIND records");
1938  return Error::success();
1939 }
1940 
1941 /// Parse the metadata kinds out of the METADATA_KIND_BLOCK.
1944  return error("Invalid record");
1945 
1947 
1948  // Read all the records.
1949  while (true) {
1950  BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
1951 
1952  switch (Entry.Kind) {
1953  case BitstreamEntry::SubBlock: // Handled for us already.
1954  case BitstreamEntry::Error:
1955  return error("Malformed block");
1957  return Error::success();
1959  // The interesting case.
1960  break;
1961  }
1962 
1963  // Read a record.
1964  Record.clear();
1965  ++NumMDRecordLoaded;
1966  unsigned Code = Stream.readRecord(Entry.ID, Record);
1967  switch (Code) {
1968  default: // Default behavior: ignore.
1969  break;
1970  case bitc::METADATA_KIND: {
1971  if (Error Err = parseMetadataKindRecord(Record))
1972  return Err;
1973  break;
1974  }
1975  }
1976  }
1977 }
1978 
1980  Pimpl = std::move(RHS.Pimpl);
1981  return *this;
1982 }
1984  : Pimpl(std::move(RHS.Pimpl)) {}
1985 
1988  BitcodeReaderValueList &ValueList,
1989  bool IsImporting,
1990  std::function<Type *(unsigned)> getTypeByID)
1992  Stream, TheModule, ValueList, std::move(getTypeByID), IsImporting)) {}
1993 
1994 Error MetadataLoader::parseMetadata(bool ModuleLevel) {
1995  return Pimpl->parseMetadata(ModuleLevel);
1996 }
1997 
1998 bool MetadataLoader::hasFwdRefs() const { return Pimpl->hasFwdRefs(); }
1999 
2000 /// Return the given metadata, creating a replaceable forward reference if
2001 /// necessary.
2003  return Pimpl->getMetadataFwdRefOrLoad(Idx);
2004 }
2005 
2007  return Pimpl->getMDNodeFwdRefOrNull(Idx);
2008 }
2009 
2011  return Pimpl->lookupSubprogramForFunction(F);
2012 }
2013 
2015  Function &F, const SmallVectorImpl<Instruction *> &InstructionList) {
2016  return Pimpl->parseMetadataAttachment(F, InstructionList);
2017 }
2018 
2020  return Pimpl->parseMetadataKinds();
2021 }
2022 
2023 void MetadataLoader::setStripTBAA(bool StripTBAA) {
2024  return Pimpl->setStripTBAA(StripTBAA);
2025 }
2026 
2027 bool MetadataLoader::isStrippingTBAA() { return Pimpl->isStrippingTBAA(); }
2028 
2029 unsigned MetadataLoader::size() const { return Pimpl->size(); }
2030 void MetadataLoader::shrinkTo(unsigned N) { return Pimpl->shrinkTo(N); }
2031 
2033  return Pimpl->upgradeDebugIntrinsics(F);
2034 }
uint64_t CallInst * C
bool mayBeOldLoopAttachmentTag(StringRef Name)
Check whether a string looks like an old loop attachment tag.
Definition: AutoUpgrade.h:84
bool isStrippingTBAA()
Return true if the Loader is stripping TBAA metadata.
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1133
bool empty() const
Definition: Function.h:662
GCNRegPressure max(const GCNRegPressure &P1, const GCNRegPressure &P2)
LLVMContext & Context
Atomic ordering constants.
bool isMetadataTy() const
Return true if this is &#39;metadata&#39;.
Definition: Type.h:191
LLVM_ATTRIBUTE_NORETURN void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
Definition: Error.cpp:139
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
uint64_t GetCurrentBitNo() const
Return the bit # of the bit we are reading.
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:64
#define LLVM_FALLTHROUGH
Definition: Compiler.h:86
unsigned size() const
Tracking metadata reference.
Definition: TrackingMDRef.h:26
static MDString * get(LLVMContext &Context, StringRef Str)
Definition: Metadata.cpp:454
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE size_t size() const
size - Get the string size.
Definition: StringRef.h:138
void addOperand(MDNode *M)
Definition: Metadata.cpp:1087
void emplace(ArgTypes &&... Args)
Create a new object by constructing it in place with the given arguments.
Definition: Optional.h:153
An efficient, type-erasing, non-owning reference to a callable.
Definition: STLExtras.h:107
This file contains the declaration of the Comdat class, which represents a single COMDAT in LLVM...
NamedMDNode * getOrInsertNamedMetadata(StringRef Name)
Return the named MDNode in the module with the specified name.
Definition: Module.cpp:254
STATISTIC(NumFunctions, "Total number of functions")
Metadata node.
Definition: Metadata.h:864
F(f)
block Block Frequency true
std::enable_if<!std::is_array< T >::value, std::unique_ptr< T > >::type make_unique(Args &&... args)
Constructs a new T() with the given args and returns a unique_ptr<T> which owns the object...
Definition: STLExtras.h:1205
Error parseMetadataAttachment(Function &F, const SmallVectorImpl< Instruction *> &InstructionList)
Parse metadata attachments.
void upgradeDebugIntrinsics(Function &F)
Perform bitcode upgrades on llvm.dbg.* calls.
void setStripTBAA(bool StripTBAA=true)
Set the mode to strip TBAA metadata on load.
void reserve(size_type N)
Definition: SmallVector.h:376
bool isForwardDecl() const
Value * getValueFwdRef(unsigned Idx, Type *Ty)
Definition: ValueList.cpp:113
#define LLVM_UNLIKELY(EXPR)
Definition: Compiler.h:192
std::pair< iterator, bool > insert(const std::pair< KeyT, ValueT > &KV)
Definition: DenseMap.h:196
A tuple of MDNodes.
Definition: Metadata.h:1326
amdgpu Simplify well known AMD library false Value Value const Twine & Name
Definition: BitVector.h:938
MDNode * upgradeInstructionLoopAttachment(MDNode &N)
Upgrade the loop attachment metadata node.
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
Metadata * getMetadataFwdRefOrLoad(unsigned ID)
Array subrange.
The access may reference the value stored in memory.
static cl::opt< bool > DisableLazyLoading("disable-ondemand-mds-loading", cl::init(false), cl::Hidden, cl::desc("Force disable the lazy-loading on-demand of metadata when " "loading bitcode for importing."))
std::error_code make_error_code(BitcodeError E)
This file contains the simple types necessary to represent the attributes associated with functions a...
static TempMDTuple getTemporary(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1178
Placeholder metadata for operands of distinct MDNodes.
Definition: Metadata.h:1281
Only used in LLVM metadata.
Definition: Dwarf.h:132
Tagged union holding either a T or a Error.
Definition: CachePruning.h:23
static const uint16_t * lookup(unsigned opcode, unsigned domain, ArrayRef< uint16_t[3]> Table)
This file implements a class to represent arbitrary precision integral constant values and operations...
uint32_t ReadVBR(unsigned NumBits)
Subprogram description.
Error parseMetadata(bool ModuleLevel)
Parse a METADATA_BLOCK.
unsigned size() const
Definition: ValueList.h:51
Enumeration value.
NamedMDNode * getNamedMetadata(const Twine &Name) const
Return the first NamedMDNode in the module with the specified name.
Definition: Module.cpp:245
static cl::opt< bool > ImportFullTypeDefinitions("import-full-type-definitions", cl::init(false), cl::Hidden, cl::desc("Import full type definitions for ThinLTO."))
Flag whether we need to import full type definitions for ThinLTO.
BitstreamEntry advanceSkippingSubblocks(unsigned Flags=0)
This is a convenience function for clients that don&#39;t expect any subblocks.
Debug location.
iterator find(const_arg_type_t< KeyT > Val)
Definition: DenseMap.h:151
static MetadataAsValue * get(LLVMContext &Context, Metadata *MD)
Definition: Metadata.cpp:106
bool isVoidTy() const
Return true if this is &#39;void&#39;.
Definition: Type.h:141
static TempMDTuple getTemporary(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Return a temporary node.
Definition: Metadata.h:1153
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1166
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:410
void setSubprogram(DISubprogram *SP)
Set the attached subprogram.
Definition: Metadata.cpp:1504
MetadataLoaderImpl(BitstreamCursor &Stream, Module &TheModule, BitcodeReaderValueList &ValueList, std::function< Type *(unsigned)> getTypeByID, bool IsImporting)
MutableArrayRef - Represent a mutable reference to an array (0 or more elements consecutively in memo...
Definition: ArrayRef.h:291
Metadata * get() const
Definition: TrackingMDRef.h:58
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:46
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:69
size_t size() const
size - Get the array size.
Definition: ArrayRef.h:149
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
This represents a position within a bitcode file, implemented on top of a SimpleBitstreamCursor.
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator begin()
Definition: SmallVector.h:129
static MDTuple * getDistinct(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1174
This file contains the declarations for the subclasses of Constant, which represent the different fla...
void shrinkTo(unsigned N)
A pair of DIGlobalVariable and DIExpression.
This file declares a class to represent arbitrary precision floating point values and provide a varie...
bool isMaterializable() const
Definition: Function.h:179
static LocalAsMetadata * get(Value *Local)
Definition: Metadata.h:436
void JumpToBit(uint64_t BitNo)
Reset the stream to the specified bit number.
Metadata * getMetadataFwdRefOrLoad(unsigned Idx)
Return the given metadata, creating a replaceable forward reference if necessary. ...
bool SkipBlock()
Having read the ENTER_SUBBLOCK abbrevid and a BlockID, skip over the body of this block...
size_t size() const
Definition: SmallVector.h:53
void setMetadata(unsigned KindID, MDNode *Node)
Set the metadata of the specified kind to the specified node.
Definition: Metadata.cpp:1226
An imported module (C++ using directive or similar).
BaseType
A given derived pointer can have multiple base pointers through phi/selects.
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef drop_front(size_t N=1) const
Return a StringRef equal to &#39;this&#39; but with the first N elements dropped.
Definition: StringRef.h:645
static ErrorSuccess success()
Create a success value.
Definition: Error.h:327
When advancing through a bitstream cursor, each advance can discover a few different kinds of entries...
auto size(R &&Range, typename std::enable_if< std::is_same< typename std::iterator_traits< decltype(Range.begin())>::iterator_category, std::random_access_iterator_tag >::value, void >::type *=nullptr) -> decltype(std::distance(Range.begin(), Range.end()))
Get the size of a range.
Definition: STLExtras.h:1023
Helper class that handles loading Metadatas and keeping them available.
static Error error(const Twine &Message)
static ValueAsMetadata * get(Value *V)
Definition: Metadata.cpp:349
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:847
Module.h This file contains the declarations for the Module class.
unsigned readRecord(unsigned AbbrevID, SmallVectorImpl< uint64_t > &Vals, StringRef *Blob=nullptr)
void addMetadata(unsigned KindID, MDNode &MD)
Add a metadata attachment.
Definition: Metadata.cpp:1394
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef slice(size_t Start, size_t End) const
Return a reference to the substring from [Start, End).
Definition: StringRef.h:710
DISubprogram * lookupSubprogramForFunction(Function *F)
Return the DISubprogram metadata for a Function if any, null otherwise.
DWARF expression.
DISubprogram * lookupSubprogramForFunction(Function *F)
Implements a dense probed hash-table based set with some number of buckets stored inline...
Definition: DenseSet.h:268
MDNode * UpgradeTBAANode(MDNode &TBAANode)
If the given TBAA tag uses the scalar TBAA format, create a new node corresponding to the upgrade to ...
unsigned skipRecord(unsigned AbbrevID)
Read the current record and discard it, returning the code for the record.
A (clang) module that has been imported by the compile unit.
Error parseMetadataKinds()
Parse a METADATA_KIND block for the current module.
MDNode * getMDNodeFwdRefOrNull(unsigned Idx)
iterator begin() const
Definition: ArrayRef.h:331
Generic tagged DWARF-like metadata node.
static void clear(coro::Shape &Shape)
Definition: Coroutines.cpp:212
void append(in_iter in_start, in_iter in_end)
Add the specified range to the end of the SmallVector.
Definition: SmallVector.h:394
Type array for a subprogram.
DIFlags
Debug info flags.
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator end()
Definition: SmallVector.h:133
MDString * getRawIdentifier() const
void emplace_back(ArgTypes &&... Args)
Definition: SmallVector.h:652
bool EnterSubBlock(unsigned BlockID, unsigned *NumWordsP=nullptr)
Having read the ENTER_SUBBLOCK abbrevid, enter the block, and return true if the block has an error...
LLVM_NODISCARD bool empty() const
Definition: SmallVector.h:56
#define I(x, y, z)
Definition: MD5.cpp:58
#define N
iterator end()
Definition: DenseMap.h:84
uint32_t Size
Definition: Profile.cpp:47
ValueT lookup(const_arg_type_t< KeyT > Val) const
lookup - Return the entry for the specified key, or a default constructed value if no such entry exis...
Definition: DenseMap.h:186
MetadataLoader & operator=(MetadataLoader &&)
const unsigned Kind
MetadataLoader(BitstreamCursor &Stream, Module &TheModule, BitcodeReaderValueList &ValueList, bool IsImporting, std::function< Type *(unsigned)> getTypeByID)
static DICompositeType * buildODRType(LLVMContext &Context, MDString &Identifier, unsigned Tag, MDString *Name, Metadata *File, unsigned Line, Metadata *Scope, Metadata *BaseType, uint64_t SizeInBits, uint32_t AlignInBits, uint64_t OffsetInBits, DIFlags Flags, Metadata *Elements, unsigned RuntimeLang, Metadata *VTableHolder, Metadata *TemplateParams, Metadata *Discriminator)
Build a DICompositeType with the given ODR identifier.
unsigned getMDKindID(StringRef Name) const
Return a unique non-zero ID for the specified metadata kind.
Definition: Module.cpp:119
ModuleSummaryIndex.h This file contains the declarations the classes that hold the module index and s...
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
Error parseMetadataAttachment(Function &F, const SmallVectorImpl< Instruction *> &InstructionList)
Parse a METADATA_ATTACHMENT block for a function.
LLVM Value Representation.
Definition: Value.h:73
#define GET_OR_DISTINCT(CLASS, ARGS)
enum llvm::BitstreamEntry::@144 Kind
Lightweight error class with error context and mandatory checking.
Definition: Error.h:158
iterator end() const
Definition: ArrayRef.h:332
#define LLVM_LIKELY(EXPR)
Definition: Compiler.h:191
bool isTemporary() const
Definition: Metadata.h:944
void addDebugInfo(DIGlobalVariableExpression *GV)
Attach a DIGlobalVariableExpression.
Definition: Metadata.cpp:1521
If this flag is used, the advance() method does not automatically pop the block scope when the end of...
print Print MemDeps of function
iterator_range< global_iterator > globals()
Definition: Module.h:574
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
A single uniqued string.
Definition: Metadata.h:604
This represents a position within a bitstream.
Error parseMetadataKinds()
Parse the metadata kinds out of the METADATA_KIND_BLOCK.
Root of the metadata hierarchy.
Definition: Metadata.h:58
const uint64_t Version
Definition: InstrProf.h:895
Function Alias Analysis false
constexpr char Args[]
Key for Kernel::Metadata::mArgs.
Basic type, like &#39;int&#39; or &#39;float&#39;.
void resize(size_type N)
Definition: SmallVector.h:351