LLVM  10.0.0svn
MetadataLoader.cpp
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1 //===- MetadataLoader.cpp - Internal BitcodeReader 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 "MetadataLoader.h"
10 #include "ValueList.h"
11 
12 #include "llvm/ADT/APFloat.h"
13 #include "llvm/ADT/APInt.h"
14 #include "llvm/ADT/ArrayRef.h"
15 #include "llvm/ADT/DenseMap.h"
16 #include "llvm/ADT/DenseSet.h"
17 #include "llvm/ADT/None.h"
18 #include "llvm/ADT/STLExtras.h"
19 #include "llvm/ADT/SmallString.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/ADT/Statistic.h"
22 #include "llvm/ADT/StringRef.h"
23 #include "llvm/ADT/Twine.h"
27 #include "llvm/IR/Argument.h"
28 #include "llvm/IR/Attributes.h"
29 #include "llvm/IR/AutoUpgrade.h"
30 #include "llvm/IR/BasicBlock.h"
31 #include "llvm/IR/CallingConv.h"
32 #include "llvm/IR/Comdat.h"
33 #include "llvm/IR/Constant.h"
34 #include "llvm/IR/Constants.h"
35 #include "llvm/IR/DebugInfo.h"
37 #include "llvm/IR/DebugLoc.h"
38 #include "llvm/IR/DerivedTypes.h"
40 #include "llvm/IR/Function.h"
41 #include "llvm/IR/GVMaterializer.h"
42 #include "llvm/IR/GlobalAlias.h"
43 #include "llvm/IR/GlobalIFunc.h"
45 #include "llvm/IR/GlobalObject.h"
46 #include "llvm/IR/GlobalValue.h"
47 #include "llvm/IR/GlobalVariable.h"
48 #include "llvm/IR/InlineAsm.h"
49 #include "llvm/IR/InstrTypes.h"
50 #include "llvm/IR/Instruction.h"
51 #include "llvm/IR/Instructions.h"
52 #include "llvm/IR/IntrinsicInst.h"
53 #include "llvm/IR/Intrinsics.h"
54 #include "llvm/IR/LLVMContext.h"
55 #include "llvm/IR/Module.h"
57 #include "llvm/IR/OperandTraits.h"
58 #include "llvm/IR/TrackingMDRef.h"
59 #include "llvm/IR/Type.h"
60 #include "llvm/IR/ValueHandle.h"
62 #include "llvm/Support/Casting.h"
64 #include "llvm/Support/Compiler.h"
65 #include "llvm/Support/Debug.h"
66 #include "llvm/Support/Error.h"
71 #include <algorithm>
72 #include <cassert>
73 #include <cstddef>
74 #include <cstdint>
75 #include <deque>
76 #include <limits>
77 #include <map>
78 #include <memory>
79 #include <string>
80 #include <system_error>
81 #include <tuple>
82 #include <utility>
83 #include <vector>
84 
85 using namespace llvm;
86 
87 #define DEBUG_TYPE "bitcode-reader"
88 
89 STATISTIC(NumMDStringLoaded, "Number of MDStrings loaded");
90 STATISTIC(NumMDNodeTemporary, "Number of MDNode::Temporary created");
91 STATISTIC(NumMDRecordLoaded, "Number of Metadata records loaded");
92 
93 /// Flag whether we need to import full type definitions for ThinLTO.
94 /// Currently needed for Darwin and LLDB.
96  "import-full-type-definitions", cl::init(false), cl::Hidden,
97  cl::desc("Import full type definitions for ThinLTO."));
98 
100  "disable-ondemand-mds-loading", cl::init(false), cl::Hidden,
101  cl::desc("Force disable the lazy-loading on-demand of metadata when "
102  "loading bitcode for importing."));
103 
104 namespace {
105 
106 static int64_t unrotateSign(uint64_t U) { return (U & 1) ? ~(U >> 1) : U >> 1; }
107 
108 class BitcodeReaderMetadataList {
109  /// Array of metadata references.
110  ///
111  /// Don't use std::vector here. Some versions of libc++ copy (instead of
112  /// move) on resize, and TrackingMDRef is very expensive to copy.
113  SmallVector<TrackingMDRef, 1> MetadataPtrs;
114 
115  /// The set of indices in MetadataPtrs above of forward references that were
116  /// generated.
117  SmallDenseSet<unsigned, 1> ForwardReference;
118 
119  /// The set of indices in MetadataPtrs above of Metadata that need to be
120  /// resolved.
121  SmallDenseSet<unsigned, 1> UnresolvedNodes;
122 
123  /// Structures for resolving old type refs.
124  struct {
129  } OldTypeRefs;
130 
132 
133  /// Maximum number of valid references. Forward references exceeding the
134  /// maximum must be invalid.
135  unsigned RefsUpperBound;
136 
137 public:
138  BitcodeReaderMetadataList(LLVMContext &C, size_t RefsUpperBound)
139  : Context(C),
140  RefsUpperBound(std::min((size_t)std::numeric_limits<unsigned>::max(),
141  RefsUpperBound)) {}
142 
143  // vector compatibility methods
144  unsigned size() const { return MetadataPtrs.size(); }
145  void resize(unsigned N) { MetadataPtrs.resize(N); }
146  void push_back(Metadata *MD) { MetadataPtrs.emplace_back(MD); }
147  void clear() { MetadataPtrs.clear(); }
148  Metadata *back() const { return MetadataPtrs.back(); }
149  void pop_back() { MetadataPtrs.pop_back(); }
150  bool empty() const { return MetadataPtrs.empty(); }
151 
152  Metadata *operator[](unsigned i) const {
153  assert(i < MetadataPtrs.size());
154  return MetadataPtrs[i];
155  }
156 
157  Metadata *lookup(unsigned I) const {
158  if (I < MetadataPtrs.size())
159  return MetadataPtrs[I];
160  return nullptr;
161  }
162 
163  void shrinkTo(unsigned N) {
164  assert(N <= size() && "Invalid shrinkTo request!");
165  assert(ForwardReference.empty() && "Unexpected forward refs");
166  assert(UnresolvedNodes.empty() && "Unexpected unresolved node");
167  MetadataPtrs.resize(N);
168  }
169 
170  /// Return the given metadata, creating a replaceable forward reference if
171  /// necessary.
172  Metadata *getMetadataFwdRef(unsigned Idx);
173 
174  /// Return the given metadata only if it is fully resolved.
175  ///
176  /// Gives the same result as \a lookup(), unless \a MDNode::isResolved()
177  /// would give \c false.
178  Metadata *getMetadataIfResolved(unsigned Idx);
179 
180  MDNode *getMDNodeFwdRefOrNull(unsigned Idx);
181  void assignValue(Metadata *MD, unsigned Idx);
182  void tryToResolveCycles();
183  bool hasFwdRefs() const { return !ForwardReference.empty(); }
184  int getNextFwdRef() {
185  assert(hasFwdRefs());
186  return *ForwardReference.begin();
187  }
188 
189  /// Upgrade a type that had an MDString reference.
190  void addTypeRef(MDString &UUID, DICompositeType &CT);
191 
192  /// Upgrade a type that had an MDString reference.
193  Metadata *upgradeTypeRef(Metadata *MaybeUUID);
194 
195  /// Upgrade a type ref array that may have MDString references.
196  Metadata *upgradeTypeRefArray(Metadata *MaybeTuple);
197 
198 private:
199  Metadata *resolveTypeRefArray(Metadata *MaybeTuple);
200 };
201 
202 void BitcodeReaderMetadataList::assignValue(Metadata *MD, unsigned Idx) {
203  if (auto *MDN = dyn_cast<MDNode>(MD))
204  if (!MDN->isResolved())
205  UnresolvedNodes.insert(Idx);
206 
207  if (Idx == size()) {
208  push_back(MD);
209  return;
210  }
211 
212  if (Idx >= size())
213  resize(Idx + 1);
214 
215  TrackingMDRef &OldMD = MetadataPtrs[Idx];
216  if (!OldMD) {
217  OldMD.reset(MD);
218  return;
219  }
220 
221  // If there was a forward reference to this value, replace it.
222  TempMDTuple PrevMD(cast<MDTuple>(OldMD.get()));
223  PrevMD->replaceAllUsesWith(MD);
224  ForwardReference.erase(Idx);
225 }
226 
227 Metadata *BitcodeReaderMetadataList::getMetadataFwdRef(unsigned Idx) {
228  // Bail out for a clearly invalid value.
229  if (Idx >= RefsUpperBound)
230  return nullptr;
231 
232  if (Idx >= size())
233  resize(Idx + 1);
234 
235  if (Metadata *MD = MetadataPtrs[Idx])
236  return MD;
237 
238  // Track forward refs to be resolved later.
239  ForwardReference.insert(Idx);
240 
241  // Create and return a placeholder, which will later be RAUW'd.
242  ++NumMDNodeTemporary;
243  Metadata *MD = MDNode::getTemporary(Context, None).release();
244  MetadataPtrs[Idx].reset(MD);
245  return MD;
246 }
247 
248 Metadata *BitcodeReaderMetadataList::getMetadataIfResolved(unsigned Idx) {
249  Metadata *MD = lookup(Idx);
250  if (auto *N = dyn_cast_or_null<MDNode>(MD))
251  if (!N->isResolved())
252  return nullptr;
253  return MD;
254 }
255 
256 MDNode *BitcodeReaderMetadataList::getMDNodeFwdRefOrNull(unsigned Idx) {
257  return dyn_cast_or_null<MDNode>(getMetadataFwdRef(Idx));
258 }
259 
260 void BitcodeReaderMetadataList::tryToResolveCycles() {
261  if (!ForwardReference.empty())
262  // Still forward references... can't resolve cycles.
263  return;
264 
265  // Give up on finding a full definition for any forward decls that remain.
266  for (const auto &Ref : OldTypeRefs.FwdDecls)
267  OldTypeRefs.Final.insert(Ref);
268  OldTypeRefs.FwdDecls.clear();
269 
270  // Upgrade from old type ref arrays. In strange cases, this could add to
271  // OldTypeRefs.Unknown.
272  for (const auto &Array : OldTypeRefs.Arrays)
273  Array.second->replaceAllUsesWith(resolveTypeRefArray(Array.first.get()));
274  OldTypeRefs.Arrays.clear();
275 
276  // Replace old string-based type refs with the resolved node, if possible.
277  // If we haven't seen the node, leave it to the verifier to complain about
278  // the invalid string reference.
279  for (const auto &Ref : OldTypeRefs.Unknown) {
280  if (DICompositeType *CT = OldTypeRefs.Final.lookup(Ref.first))
281  Ref.second->replaceAllUsesWith(CT);
282  else
283  Ref.second->replaceAllUsesWith(Ref.first);
284  }
285  OldTypeRefs.Unknown.clear();
286 
287  if (UnresolvedNodes.empty())
288  // Nothing to do.
289  return;
290 
291  // Resolve any cycles.
292  for (unsigned I : UnresolvedNodes) {
293  auto &MD = MetadataPtrs[I];
294  auto *N = dyn_cast_or_null<MDNode>(MD);
295  if (!N)
296  continue;
297 
298  assert(!N->isTemporary() && "Unexpected forward reference");
299  N->resolveCycles();
300  }
301 
302  // Make sure we return early again until there's another unresolved ref.
303  UnresolvedNodes.clear();
304 }
305 
306 void BitcodeReaderMetadataList::addTypeRef(MDString &UUID,
307  DICompositeType &CT) {
308  assert(CT.getRawIdentifier() == &UUID && "Mismatched UUID");
309  if (CT.isForwardDecl())
310  OldTypeRefs.FwdDecls.insert(std::make_pair(&UUID, &CT));
311  else
312  OldTypeRefs.Final.insert(std::make_pair(&UUID, &CT));
313 }
314 
315 Metadata *BitcodeReaderMetadataList::upgradeTypeRef(Metadata *MaybeUUID) {
316  auto *UUID = dyn_cast_or_null<MDString>(MaybeUUID);
317  if (LLVM_LIKELY(!UUID))
318  return MaybeUUID;
319 
320  if (auto *CT = OldTypeRefs.Final.lookup(UUID))
321  return CT;
322 
323  auto &Ref = OldTypeRefs.Unknown[UUID];
324  if (!Ref)
325  Ref = MDNode::getTemporary(Context, None);
326  return Ref.get();
327 }
328 
329 Metadata *BitcodeReaderMetadataList::upgradeTypeRefArray(Metadata *MaybeTuple) {
330  auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple);
331  if (!Tuple || Tuple->isDistinct())
332  return MaybeTuple;
333 
334  // Look through the array immediately if possible.
335  if (!Tuple->isTemporary())
336  return resolveTypeRefArray(Tuple);
337 
338  // Create and return a placeholder to use for now. Eventually
339  // resolveTypeRefArrays() will be resolve this forward reference.
340  OldTypeRefs.Arrays.emplace_back(
341  std::piecewise_construct, std::forward_as_tuple(Tuple),
342  std::forward_as_tuple(MDTuple::getTemporary(Context, None)));
343  return OldTypeRefs.Arrays.back().second.get();
344 }
345 
346 Metadata *BitcodeReaderMetadataList::resolveTypeRefArray(Metadata *MaybeTuple) {
347  auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple);
348  if (!Tuple || Tuple->isDistinct())
349  return MaybeTuple;
350 
351  // Look through the DITypeRefArray, upgrading each DIType *.
353  Ops.reserve(Tuple->getNumOperands());
354  for (Metadata *MD : Tuple->operands())
355  Ops.push_back(upgradeTypeRef(MD));
356 
357  return MDTuple::get(Context, Ops);
358 }
359 
360 namespace {
361 
362 class PlaceholderQueue {
363  // Placeholders would thrash around when moved, so store in a std::deque
364  // instead of some sort of vector.
365  std::deque<DistinctMDOperandPlaceholder> PHs;
366 
367 public:
368  ~PlaceholderQueue() {
369  assert(empty() && "PlaceholderQueue hasn't been flushed before being destroyed");
370  }
371  bool empty() { return PHs.empty(); }
372  DistinctMDOperandPlaceholder &getPlaceholderOp(unsigned ID);
373  void flush(BitcodeReaderMetadataList &MetadataList);
374 
375  /// Return the list of temporaries nodes in the queue, these need to be
376  /// loaded before we can flush the queue.
377  void getTemporaries(BitcodeReaderMetadataList &MetadataList,
378  DenseSet<unsigned> &Temporaries) {
379  for (auto &PH : PHs) {
380  auto ID = PH.getID();
381  auto *MD = MetadataList.lookup(ID);
382  if (!MD) {
383  Temporaries.insert(ID);
384  continue;
385  }
386  auto *N = dyn_cast_or_null<MDNode>(MD);
387  if (N && N->isTemporary())
388  Temporaries.insert(ID);
389  }
390  }
391 };
392 
393 } // end anonymous namespace
394 
395 DistinctMDOperandPlaceholder &PlaceholderQueue::getPlaceholderOp(unsigned ID) {
396  PHs.emplace_back(ID);
397  return PHs.back();
398 }
399 
400 void PlaceholderQueue::flush(BitcodeReaderMetadataList &MetadataList) {
401  while (!PHs.empty()) {
402  auto *MD = MetadataList.lookup(PHs.front().getID());
403  assert(MD && "Flushing placeholder on unassigned MD");
404 #ifndef NDEBUG
405  if (auto *MDN = dyn_cast<MDNode>(MD))
406  assert(MDN->isResolved() &&
407  "Flushing Placeholder while cycles aren't resolved");
408 #endif
409  PHs.front().replaceUseWith(MD);
410  PHs.pop_front();
411  }
412 }
413 
414 } // anonynous namespace
415 
416 static Error error(const Twine &Message) {
417  return make_error<StringError>(
419 }
420 
422  BitcodeReaderMetadataList MetadataList;
423  BitcodeReaderValueList &ValueList;
424  BitstreamCursor &Stream;
426  Module &TheModule;
427  std::function<Type *(unsigned)> getTypeByID;
428 
429  /// Cursor associated with the lazy-loading of Metadata. This is the easy way
430  /// to keep around the right "context" (Abbrev list) to be able to jump in
431  /// the middle of the metadata block and load any record.
432  BitstreamCursor IndexCursor;
433 
434  /// Index that keeps track of MDString values.
435  std::vector<StringRef> MDStringRef;
436 
437  /// On-demand loading of a single MDString. Requires the index above to be
438  /// populated.
439  MDString *lazyLoadOneMDString(unsigned Idx);
440 
441  /// Index that keeps track of where to find a metadata record in the stream.
442  std::vector<uint64_t> GlobalMetadataBitPosIndex;
443 
444  /// Populate the index above to enable lazily loading of metadata, and load
445  /// the named metadata as well as the transitively referenced global
446  /// Metadata.
447  Expected<bool> lazyLoadModuleMetadataBlock();
448 
449  /// On-demand loading of a single metadata. Requires the index above to be
450  /// populated.
451  void lazyLoadOneMetadata(unsigned Idx, PlaceholderQueue &Placeholders);
452 
453  // Keep mapping of seens pair of old-style CU <-> SP, and update pointers to
454  // point from SP to CU after a block is completly parsed.
455  std::vector<std::pair<DICompileUnit *, Metadata *>> CUSubprograms;
456 
457  /// Functions that need to be matched with subprograms when upgrading old
458  /// metadata.
460 
461  // Map the bitcode's custom MDKind ID to the Module's MDKind ID.
463 
464  bool StripTBAA = false;
465  bool HasSeenOldLoopTags = false;
466  bool NeedUpgradeToDIGlobalVariableExpression = false;
467  bool NeedDeclareExpressionUpgrade = false;
468 
469  /// True if metadata is being parsed for a module being ThinLTO imported.
470  bool IsImporting = false;
471 
472  Error parseOneMetadata(SmallVectorImpl<uint64_t> &Record, unsigned Code,
473  PlaceholderQueue &Placeholders, StringRef Blob,
474  unsigned &NextMetadataNo);
475  Error parseMetadataStrings(ArrayRef<uint64_t> Record, StringRef Blob,
476  function_ref<void(StringRef)> CallBack);
477  Error parseGlobalObjectAttachment(GlobalObject &GO,
478  ArrayRef<uint64_t> Record);
479  Error parseMetadataKindRecord(SmallVectorImpl<uint64_t> &Record);
480 
481  void resolveForwardRefsAndPlaceholders(PlaceholderQueue &Placeholders);
482 
483  /// Upgrade old-style CU <-> SP pointers to point from SP to CU.
484  void upgradeCUSubprograms() {
485  for (auto CU_SP : CUSubprograms)
486  if (auto *SPs = dyn_cast_or_null<MDTuple>(CU_SP.second))
487  for (auto &Op : SPs->operands())
488  if (auto *SP = dyn_cast_or_null<DISubprogram>(Op))
489  SP->replaceUnit(CU_SP.first);
490  CUSubprograms.clear();
491  }
492 
493  /// Upgrade old-style bare DIGlobalVariables to DIGlobalVariableExpressions.
494  void upgradeCUVariables() {
495  if (!NeedUpgradeToDIGlobalVariableExpression)
496  return;
497 
498  // Upgrade list of variables attached to the CUs.
499  if (NamedMDNode *CUNodes = TheModule.getNamedMetadata("llvm.dbg.cu"))
500  for (unsigned I = 0, E = CUNodes->getNumOperands(); I != E; ++I) {
501  auto *CU = cast<DICompileUnit>(CUNodes->getOperand(I));
502  if (auto *GVs = dyn_cast_or_null<MDTuple>(CU->getRawGlobalVariables()))
503  for (unsigned I = 0; I < GVs->getNumOperands(); I++)
504  if (auto *GV =
505  dyn_cast_or_null<DIGlobalVariable>(GVs->getOperand(I))) {
507  Context, GV, DIExpression::get(Context, {}));
508  GVs->replaceOperandWith(I, DGVE);
509  }
510  }
511 
512  // Upgrade variables attached to globals.
513  for (auto &GV : TheModule.globals()) {
515  GV.getMetadata(LLVMContext::MD_dbg, MDs);
516  GV.eraseMetadata(LLVMContext::MD_dbg);
517  for (auto *MD : MDs)
518  if (auto *DGV = dyn_cast_or_null<DIGlobalVariable>(MD)) {
520  Context, DGV, DIExpression::get(Context, {}));
521  GV.addMetadata(LLVMContext::MD_dbg, *DGVE);
522  } else
523  GV.addMetadata(LLVMContext::MD_dbg, *MD);
524  }
525  }
526 
527  /// Remove a leading DW_OP_deref from DIExpressions in a dbg.declare that
528  /// describes a function argument.
529  void upgradeDeclareExpressions(Function &F) {
530  if (!NeedDeclareExpressionUpgrade)
531  return;
532 
533  for (auto &BB : F)
534  for (auto &I : BB)
535  if (auto *DDI = dyn_cast<DbgDeclareInst>(&I))
536  if (auto *DIExpr = DDI->getExpression())
537  if (DIExpr->startsWithDeref() &&
538  dyn_cast_or_null<Argument>(DDI->getAddress())) {
540  Ops.append(std::next(DIExpr->elements_begin()),
541  DIExpr->elements_end());
542  auto *E = DIExpression::get(Context, Ops);
543  DDI->setOperand(2, MetadataAsValue::get(Context, E));
544  }
545  }
546 
547  /// Upgrade the expression from previous versions.
548  Error upgradeDIExpression(uint64_t FromVersion,
550  SmallVectorImpl<uint64_t> &Buffer) {
551  auto N = Expr.size();
552  switch (FromVersion) {
553  default:
554  return error("Invalid record");
555  case 0:
556  if (N >= 3 && Expr[N - 3] == dwarf::DW_OP_bit_piece)
557  Expr[N - 3] = dwarf::DW_OP_LLVM_fragment;
559  case 1:
560  // Move DW_OP_deref to the end.
561  if (N && Expr[0] == dwarf::DW_OP_deref) {
562  auto End = Expr.end();
563  if (Expr.size() >= 3 &&
564  *std::prev(End, 3) == dwarf::DW_OP_LLVM_fragment)
565  End = std::prev(End, 3);
566  std::move(std::next(Expr.begin()), End, Expr.begin());
567  *std::prev(End) = dwarf::DW_OP_deref;
568  }
569  NeedDeclareExpressionUpgrade = true;
571  case 2: {
572  // Change DW_OP_plus to DW_OP_plus_uconst.
573  // Change DW_OP_minus to DW_OP_uconst, DW_OP_minus
574  auto SubExpr = ArrayRef<uint64_t>(Expr);
575  while (!SubExpr.empty()) {
576  // Skip past other operators with their operands
577  // for this version of the IR, obtained from
578  // from historic DIExpression::ExprOperand::getSize().
579  size_t HistoricSize;
580  switch (SubExpr.front()) {
581  default:
582  HistoricSize = 1;
583  break;
584  case dwarf::DW_OP_constu:
585  case dwarf::DW_OP_minus:
586  case dwarf::DW_OP_plus:
587  HistoricSize = 2;
588  break;
590  HistoricSize = 3;
591  break;
592  }
593 
594  // If the expression is malformed, make sure we don't
595  // copy more elements than we should.
596  HistoricSize = std::min(SubExpr.size(), HistoricSize);
597  ArrayRef<uint64_t> Args = SubExpr.slice(1, HistoricSize-1);
598 
599  switch (SubExpr.front()) {
600  case dwarf::DW_OP_plus:
601  Buffer.push_back(dwarf::DW_OP_plus_uconst);
602  Buffer.append(Args.begin(), Args.end());
603  break;
604  case dwarf::DW_OP_minus:
605  Buffer.push_back(dwarf::DW_OP_constu);
606  Buffer.append(Args.begin(), Args.end());
607  Buffer.push_back(dwarf::DW_OP_minus);
608  break;
609  default:
610  Buffer.push_back(*SubExpr.begin());
611  Buffer.append(Args.begin(), Args.end());
612  break;
613  }
614 
615  // Continue with remaining elements.
616  SubExpr = SubExpr.slice(HistoricSize);
617  }
618  Expr = MutableArrayRef<uint64_t>(Buffer);
620  }
621  case 3:
622  // Up-to-date!
623  break;
624  }
625 
626  return Error::success();
627  }
628 
629  void upgradeDebugInfo() {
630  upgradeCUSubprograms();
631  upgradeCUVariables();
632  }
633 
634 public:
636  BitcodeReaderValueList &ValueList,
637  std::function<Type *(unsigned)> getTypeByID,
638  bool IsImporting)
639  : MetadataList(TheModule.getContext(), Stream.SizeInBytes()),
640  ValueList(ValueList), Stream(Stream), Context(TheModule.getContext()),
641  TheModule(TheModule), getTypeByID(std::move(getTypeByID)),
642  IsImporting(IsImporting) {}
643 
644  Error parseMetadata(bool ModuleLevel);
645 
646  bool hasFwdRefs() const { return MetadataList.hasFwdRefs(); }
647 
649  if (ID < MDStringRef.size())
650  return lazyLoadOneMDString(ID);
651  if (auto *MD = MetadataList.lookup(ID))
652  return MD;
653  // If lazy-loading is enabled, we try recursively to load the operand
654  // instead of creating a temporary.
655  if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) {
656  PlaceholderQueue Placeholders;
657  lazyLoadOneMetadata(ID, Placeholders);
658  resolveForwardRefsAndPlaceholders(Placeholders);
659  return MetadataList.lookup(ID);
660  }
661  return MetadataList.getMetadataFwdRef(ID);
662  }
663 
665  return FunctionsWithSPs.lookup(F);
666  }
667 
668  bool hasSeenOldLoopTags() { return HasSeenOldLoopTags; }
669 
670  Error parseMetadataAttachment(
671  Function &F, const SmallVectorImpl<Instruction *> &InstructionList);
672 
673  Error parseMetadataKinds();
674 
675  void setStripTBAA(bool Value) { StripTBAA = Value; }
676  bool isStrippingTBAA() { return StripTBAA; }
677 
678  unsigned size() const { return MetadataList.size(); }
679  void shrinkTo(unsigned N) { MetadataList.shrinkTo(N); }
680  void upgradeDebugIntrinsics(Function &F) { upgradeDeclareExpressions(F); }
681 };
682 
684 MetadataLoader::MetadataLoaderImpl::lazyLoadModuleMetadataBlock() {
685  IndexCursor = Stream;
687  // Get the abbrevs, and preload record positions to make them lazy-loadable.
688  while (true) {
689  Expected<BitstreamEntry> MaybeEntry = IndexCursor.advanceSkippingSubblocks(
691  if (!MaybeEntry)
692  return MaybeEntry.takeError();
693  BitstreamEntry Entry = MaybeEntry.get();
694 
695  switch (Entry.Kind) {
696  case BitstreamEntry::SubBlock: // Handled for us already.
698  return error("Malformed block");
700  return true;
701  }
702  case BitstreamEntry::Record: {
703  // The interesting case.
704  ++NumMDRecordLoaded;
705  uint64_t CurrentPos = IndexCursor.GetCurrentBitNo();
706  Expected<unsigned> MaybeCode = IndexCursor.skipRecord(Entry.ID);
707  if (!MaybeCode)
708  return MaybeCode.takeError();
709  unsigned Code = MaybeCode.get();
710  switch (Code) {
711  case bitc::METADATA_STRINGS: {
712  // Rewind and parse the strings.
713  if (Error Err = IndexCursor.JumpToBit(CurrentPos))
714  return std::move(Err);
715  StringRef Blob;
716  Record.clear();
717  if (Expected<unsigned> MaybeRecord =
718  IndexCursor.readRecord(Entry.ID, Record, &Blob))
719  ;
720  else
721  return MaybeRecord.takeError();
722  unsigned NumStrings = Record[0];
723  MDStringRef.reserve(NumStrings);
724  auto IndexNextMDString = [&](StringRef Str) {
725  MDStringRef.push_back(Str);
726  };
727  if (auto Err = parseMetadataStrings(Record, Blob, IndexNextMDString))
728  return std::move(Err);
729  break;
730  }
732  // This is the offset to the index, when we see this we skip all the
733  // records and load only an index to these.
734  if (Error Err = IndexCursor.JumpToBit(CurrentPos))
735  return std::move(Err);
736  Record.clear();
737  if (Expected<unsigned> MaybeRecord =
738  IndexCursor.readRecord(Entry.ID, Record))
739  ;
740  else
741  return MaybeRecord.takeError();
742  if (Record.size() != 2)
743  return error("Invalid record");
744  auto Offset = Record[0] + (Record[1] << 32);
745  auto BeginPos = IndexCursor.GetCurrentBitNo();
746  if (Error Err = IndexCursor.JumpToBit(BeginPos + Offset))
747  return std::move(Err);
748  Expected<BitstreamEntry> MaybeEntry =
749  IndexCursor.advanceSkippingSubblocks(
751  if (!MaybeEntry)
752  return MaybeEntry.takeError();
753  Entry = MaybeEntry.get();
755  "Corrupted bitcode: Expected `Record` when trying to find the "
756  "Metadata index");
757  Record.clear();
758  if (Expected<unsigned> MaybeCode =
759  IndexCursor.readRecord(Entry.ID, Record))
760  assert(MaybeCode.get() == bitc::METADATA_INDEX &&
761  "Corrupted bitcode: Expected `METADATA_INDEX` when trying to "
762  "find the Metadata index");
763  else
764  return MaybeCode.takeError();
765  // Delta unpack
766  auto CurrentValue = BeginPos;
767  GlobalMetadataBitPosIndex.reserve(Record.size());
768  for (auto &Elt : Record) {
769  CurrentValue += Elt;
770  GlobalMetadataBitPosIndex.push_back(CurrentValue);
771  }
772  break;
773  }
775  // We don't expect to get there, the Index is loaded when we encounter
776  // the offset.
777  return error("Corrupted Metadata block");
778  case bitc::METADATA_NAME: {
779  // Named metadata need to be materialized now and aren't deferred.
780  if (Error Err = IndexCursor.JumpToBit(CurrentPos))
781  return std::move(Err);
782  Record.clear();
783 
784  unsigned Code;
785  if (Expected<unsigned> MaybeCode =
786  IndexCursor.readRecord(Entry.ID, Record)) {
787  Code = MaybeCode.get();
788  assert(Code == bitc::METADATA_NAME);
789  } else
790  return MaybeCode.takeError();
791 
792  // Read name of the named metadata.
793  SmallString<8> Name(Record.begin(), Record.end());
794  if (Expected<unsigned> MaybeCode = IndexCursor.ReadCode())
795  Code = MaybeCode.get();
796  else
797  return MaybeCode.takeError();
798 
799  // Named Metadata comes in two parts, we expect the name to be followed
800  // by the node
801  Record.clear();
802  if (Expected<unsigned> MaybeNextBitCode =
803  IndexCursor.readRecord(Code, Record))
804  assert(MaybeNextBitCode.get() == bitc::METADATA_NAMED_NODE);
805  else
806  return MaybeNextBitCode.takeError();
807 
808  // Read named metadata elements.
809  unsigned Size = Record.size();
810  NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name);
811  for (unsigned i = 0; i != Size; ++i) {
812  // FIXME: We could use a placeholder here, however NamedMDNode are
813  // taking MDNode as operand and not using the Metadata infrastructure.
814  // It is acknowledged by 'TODO: Inherit from Metadata' in the
815  // NamedMDNode class definition.
816  MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]);
817  assert(MD && "Invalid metadata: expect fwd ref to MDNode");
818  NMD->addOperand(MD);
819  }
820  break;
821  }
823  // FIXME: we need to do this early because we don't materialize global
824  // value explicitly.
825  if (Error Err = IndexCursor.JumpToBit(CurrentPos))
826  return std::move(Err);
827  Record.clear();
828  if (Expected<unsigned> MaybeRecord =
829  IndexCursor.readRecord(Entry.ID, Record))
830  ;
831  else
832  return MaybeRecord.takeError();
833  if (Record.size() % 2 == 0)
834  return error("Invalid record");
835  unsigned ValueID = Record[0];
836  if (ValueID >= ValueList.size())
837  return error("Invalid record");
838  if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID]))
839  if (Error Err = parseGlobalObjectAttachment(
840  *GO, ArrayRef<uint64_t>(Record).slice(1)))
841  return std::move(Err);
842  break;
843  }
844  case bitc::METADATA_KIND:
850  case bitc::METADATA_NODE:
860  case bitc::METADATA_FILE:
878  // We don't expect to see any of these, if we see one, give up on
879  // lazy-loading and fallback.
880  MDStringRef.clear();
881  GlobalMetadataBitPosIndex.clear();
882  return false;
883  }
884  break;
885  }
886  }
887  }
888 }
889 
890 /// Parse a METADATA_BLOCK. If ModuleLevel is true then we are parsing
891 /// module level metadata.
893  if (!ModuleLevel && MetadataList.hasFwdRefs())
894  return error("Invalid metadata: fwd refs into function blocks");
895 
896  // Record the entry position so that we can jump back here and efficiently
897  // skip the whole block in case we lazy-load.
898  auto EntryPos = Stream.GetCurrentBitNo();
899 
900  if (Error Err = Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID))
901  return Err;
902 
904  PlaceholderQueue Placeholders;
905 
906  // We lazy-load module-level metadata: we build an index for each record, and
907  // then load individual record as needed, starting with the named metadata.
908  if (ModuleLevel && IsImporting && MetadataList.empty() &&
910  auto SuccessOrErr = lazyLoadModuleMetadataBlock();
911  if (!SuccessOrErr)
912  return SuccessOrErr.takeError();
913  if (SuccessOrErr.get()) {
914  // An index was successfully created and we will be able to load metadata
915  // on-demand.
916  MetadataList.resize(MDStringRef.size() +
917  GlobalMetadataBitPosIndex.size());
918 
919  // Reading the named metadata created forward references and/or
920  // placeholders, that we flush here.
921  resolveForwardRefsAndPlaceholders(Placeholders);
922  upgradeDebugInfo();
923  // Return at the beginning of the block, since it is easy to skip it
924  // entirely from there.
925  Stream.ReadBlockEnd(); // Pop the abbrev block context.
926  if (Error Err = IndexCursor.JumpToBit(EntryPos))
927  return Err;
928  if (Error Err = Stream.SkipBlock()) {
929  // FIXME this drops the error on the floor, which
930  // ThinLTO/X86/debuginfo-cu-import.ll relies on.
931  consumeError(std::move(Err));
932  return Error::success();
933  }
934  return Error::success();
935  }
936  // Couldn't load an index, fallback to loading all the block "old-style".
937  }
938 
939  unsigned NextMetadataNo = MetadataList.size();
940 
941  // Read all the records.
942  while (true) {
944  if (!MaybeEntry)
945  return MaybeEntry.takeError();
946  BitstreamEntry Entry = MaybeEntry.get();
947 
948  switch (Entry.Kind) {
949  case BitstreamEntry::SubBlock: // Handled for us already.
951  return error("Malformed block");
953  resolveForwardRefsAndPlaceholders(Placeholders);
954  upgradeDebugInfo();
955  return Error::success();
957  // The interesting case.
958  break;
959  }
960 
961  // Read a record.
962  Record.clear();
963  StringRef Blob;
964  ++NumMDRecordLoaded;
965  if (Expected<unsigned> MaybeCode =
966  Stream.readRecord(Entry.ID, Record, &Blob)) {
967  if (Error Err = parseOneMetadata(Record, MaybeCode.get(), Placeholders,
968  Blob, NextMetadataNo))
969  return Err;
970  } else
971  return MaybeCode.takeError();
972  }
973 }
974 
975 MDString *MetadataLoader::MetadataLoaderImpl::lazyLoadOneMDString(unsigned ID) {
976  ++NumMDStringLoaded;
977  if (Metadata *MD = MetadataList.lookup(ID))
978  return cast<MDString>(MD);
979  auto MDS = MDString::get(Context, MDStringRef[ID]);
980  MetadataList.assignValue(MDS, ID);
981  return MDS;
982 }
983 
984 void MetadataLoader::MetadataLoaderImpl::lazyLoadOneMetadata(
985  unsigned ID, PlaceholderQueue &Placeholders) {
986  assert(ID < (MDStringRef.size()) + GlobalMetadataBitPosIndex.size());
987  assert(ID >= MDStringRef.size() && "Unexpected lazy-loading of MDString");
988  // Lookup first if the metadata hasn't already been loaded.
989  if (auto *MD = MetadataList.lookup(ID)) {
990  auto *N = dyn_cast_or_null<MDNode>(MD);
991  if (!N->isTemporary())
992  return;
993  }
995  StringRef Blob;
996  if (Error Err = IndexCursor.JumpToBit(
997  GlobalMetadataBitPosIndex[ID - MDStringRef.size()]))
998  report_fatal_error("lazyLoadOneMetadata failed jumping: " +
999  toString(std::move(Err)));
1000  Expected<BitstreamEntry> MaybeEntry = IndexCursor.advanceSkippingSubblocks();
1001  if (!MaybeEntry)
1002  // FIXME this drops the error on the floor.
1003  report_fatal_error("lazyLoadOneMetadata failed advanceSkippingSubblocks: " +
1004  toString(MaybeEntry.takeError()));
1005  BitstreamEntry Entry = MaybeEntry.get();
1006  ++NumMDRecordLoaded;
1007  if (Expected<unsigned> MaybeCode =
1008  IndexCursor.readRecord(Entry.ID, Record, &Blob)) {
1009  if (Error Err =
1010  parseOneMetadata(Record, MaybeCode.get(), Placeholders, Blob, ID))
1011  report_fatal_error("Can't lazyload MD, parseOneMetadata: " +
1012  toString(std::move(Err)));
1013  } else
1014  report_fatal_error("Can't lazyload MD: " + toString(MaybeCode.takeError()));
1015 }
1016 
1017 /// Ensure that all forward-references and placeholders are resolved.
1018 /// Iteratively lazy-loading metadata on-demand if needed.
1019 void MetadataLoader::MetadataLoaderImpl::resolveForwardRefsAndPlaceholders(
1020  PlaceholderQueue &Placeholders) {
1021  DenseSet<unsigned> Temporaries;
1022  while (1) {
1023  // Populate Temporaries with the placeholders that haven't been loaded yet.
1024  Placeholders.getTemporaries(MetadataList, Temporaries);
1025 
1026  // If we don't have any temporary, or FwdReference, we're done!
1027  if (Temporaries.empty() && !MetadataList.hasFwdRefs())
1028  break;
1029 
1030  // First, load all the temporaries. This can add new placeholders or
1031  // forward references.
1032  for (auto ID : Temporaries)
1033  lazyLoadOneMetadata(ID, Placeholders);
1034  Temporaries.clear();
1035 
1036  // Second, load the forward-references. This can also add new placeholders
1037  // or forward references.
1038  while (MetadataList.hasFwdRefs())
1039  lazyLoadOneMetadata(MetadataList.getNextFwdRef(), Placeholders);
1040  }
1041  // At this point we don't have any forward reference remaining, or temporary
1042  // that haven't been loaded. We can safely drop RAUW support and mark cycles
1043  // as resolved.
1044  MetadataList.tryToResolveCycles();
1045 
1046  // Finally, everything is in place, we can replace the placeholders operands
1047  // with the final node they refer to.
1048  Placeholders.flush(MetadataList);
1049 }
1050 
1051 Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata(
1052  SmallVectorImpl<uint64_t> &Record, unsigned Code,
1053  PlaceholderQueue &Placeholders, StringRef Blob, unsigned &NextMetadataNo) {
1054 
1055  bool IsDistinct = false;
1056  auto getMD = [&](unsigned ID) -> Metadata * {
1057  if (ID < MDStringRef.size())
1058  return lazyLoadOneMDString(ID);
1059  if (!IsDistinct) {
1060  if (auto *MD = MetadataList.lookup(ID))
1061  return MD;
1062  // If lazy-loading is enabled, we try recursively to load the operand
1063  // instead of creating a temporary.
1064  if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) {
1065  // Create a temporary for the node that is referencing the operand we
1066  // will lazy-load. It is needed before recursing in case there are
1067  // uniquing cycles.
1068  MetadataList.getMetadataFwdRef(NextMetadataNo);
1069  lazyLoadOneMetadata(ID, Placeholders);
1070  return MetadataList.lookup(ID);
1071  }
1072  // Return a temporary.
1073  return MetadataList.getMetadataFwdRef(ID);
1074  }
1075  if (auto *MD = MetadataList.getMetadataIfResolved(ID))
1076  return MD;
1077  return &Placeholders.getPlaceholderOp(ID);
1078  };
1079  auto getMDOrNull = [&](unsigned ID) -> Metadata * {
1080  if (ID)
1081  return getMD(ID - 1);
1082  return nullptr;
1083  };
1084  auto getMDOrNullWithoutPlaceholders = [&](unsigned ID) -> Metadata * {
1085  if (ID)
1086  return MetadataList.getMetadataFwdRef(ID - 1);
1087  return nullptr;
1088  };
1089  auto getMDString = [&](unsigned ID) -> MDString * {
1090  // This requires that the ID is not really a forward reference. In
1091  // particular, the MDString must already have been resolved.
1092  auto MDS = getMDOrNull(ID);
1093  return cast_or_null<MDString>(MDS);
1094  };
1095 
1096  // Support for old type refs.
1097  auto getDITypeRefOrNull = [&](unsigned ID) {
1098  return MetadataList.upgradeTypeRef(getMDOrNull(ID));
1099  };
1100 
1101 #define GET_OR_DISTINCT(CLASS, ARGS) \
1102  (IsDistinct ? CLASS::getDistinct ARGS : CLASS::get ARGS)
1103 
1104  switch (Code) {
1105  default: // Default behavior: ignore.
1106  break;
1107  case bitc::METADATA_NAME: {
1108  // Read name of the named metadata.
1109  SmallString<8> Name(Record.begin(), Record.end());
1110  Record.clear();
1111  Expected<unsigned> MaybeCode = Stream.ReadCode();
1112  if (!MaybeCode)
1113  return MaybeCode.takeError();
1114  Code = MaybeCode.get();
1115 
1116  ++NumMDRecordLoaded;
1117  if (Expected<unsigned> MaybeNextBitCode = Stream.readRecord(Code, Record)) {
1118  if (MaybeNextBitCode.get() != bitc::METADATA_NAMED_NODE)
1119  return error("METADATA_NAME not followed by METADATA_NAMED_NODE");
1120  } else
1121  return MaybeNextBitCode.takeError();
1122 
1123  // Read named metadata elements.
1124  unsigned Size = Record.size();
1125  NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name);
1126  for (unsigned i = 0; i != Size; ++i) {
1127  MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]);
1128  if (!MD)
1129  return error("Invalid named metadata: expect fwd ref to MDNode");
1130  NMD->addOperand(MD);
1131  }
1132  break;
1133  }
1135  // FIXME: Remove in 4.0.
1136  // This is a LocalAsMetadata record, the only type of function-local
1137  // metadata.
1138  if (Record.size() % 2 == 1)
1139  return error("Invalid record");
1140 
1141  // If this isn't a LocalAsMetadata record, we're dropping it. This used
1142  // to be legal, but there's no upgrade path.
1143  auto dropRecord = [&] {
1144  MetadataList.assignValue(MDNode::get(Context, None), NextMetadataNo);
1145  NextMetadataNo++;
1146  };
1147  if (Record.size() != 2) {
1148  dropRecord();
1149  break;
1150  }
1151 
1152  Type *Ty = getTypeByID(Record[0]);
1153  if (Ty->isMetadataTy() || Ty->isVoidTy()) {
1154  dropRecord();
1155  break;
1156  }
1157 
1158  MetadataList.assignValue(
1159  LocalAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)),
1160  NextMetadataNo);
1161  NextMetadataNo++;
1162  break;
1163  }
1164  case bitc::METADATA_OLD_NODE: {
1165  // FIXME: Remove in 4.0.
1166  if (Record.size() % 2 == 1)
1167  return error("Invalid record");
1168 
1169  unsigned Size = Record.size();
1171  for (unsigned i = 0; i != Size; i += 2) {
1172  Type *Ty = getTypeByID(Record[i]);
1173  if (!Ty)
1174  return error("Invalid record");
1175  if (Ty->isMetadataTy())
1176  Elts.push_back(getMD(Record[i + 1]));
1177  else if (!Ty->isVoidTy()) {
1178  auto *MD =
1179  ValueAsMetadata::get(ValueList.getValueFwdRef(Record[i + 1], Ty));
1180  assert(isa<ConstantAsMetadata>(MD) &&
1181  "Expected non-function-local metadata");
1182  Elts.push_back(MD);
1183  } else
1184  Elts.push_back(nullptr);
1185  }
1186  MetadataList.assignValue(MDNode::get(Context, Elts), NextMetadataNo);
1187  NextMetadataNo++;
1188  break;
1189  }
1190  case bitc::METADATA_VALUE: {
1191  if (Record.size() != 2)
1192  return error("Invalid record");
1193 
1194  Type *Ty = getTypeByID(Record[0]);
1195  if (Ty->isMetadataTy() || Ty->isVoidTy())
1196  return error("Invalid record");
1197 
1198  MetadataList.assignValue(
1199  ValueAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)),
1200  NextMetadataNo);
1201  NextMetadataNo++;
1202  break;
1203  }
1205  IsDistinct = true;
1207  case bitc::METADATA_NODE: {
1209  Elts.reserve(Record.size());
1210  for (unsigned ID : Record)
1211  Elts.push_back(getMDOrNull(ID));
1212  MetadataList.assignValue(IsDistinct ? MDNode::getDistinct(Context, Elts)
1213  : MDNode::get(Context, Elts),
1214  NextMetadataNo);
1215  NextMetadataNo++;
1216  break;
1217  }
1218  case bitc::METADATA_LOCATION: {
1219  if (Record.size() != 5 && Record.size() != 6)
1220  return error("Invalid record");
1221 
1222  IsDistinct = Record[0];
1223  unsigned Line = Record[1];
1224  unsigned Column = Record[2];
1225  Metadata *Scope = getMD(Record[3]);
1226  Metadata *InlinedAt = getMDOrNull(Record[4]);
1227  bool ImplicitCode = Record.size() == 6 && Record[5];
1228  MetadataList.assignValue(
1229  GET_OR_DISTINCT(DILocation, (Context, Line, Column, Scope, InlinedAt,
1230  ImplicitCode)),
1231  NextMetadataNo);
1232  NextMetadataNo++;
1233  break;
1234  }
1236  if (Record.size() < 4)
1237  return error("Invalid record");
1238 
1239  IsDistinct = Record[0];
1240  unsigned Tag = Record[1];
1241  unsigned Version = Record[2];
1242 
1243  if (Tag >= 1u << 16 || Version != 0)
1244  return error("Invalid record");
1245 
1246  auto *Header = getMDString(Record[3]);
1247  SmallVector<Metadata *, 8> DwarfOps;
1248  for (unsigned I = 4, E = Record.size(); I != E; ++I)
1249  DwarfOps.push_back(getMDOrNull(Record[I]));
1250  MetadataList.assignValue(
1251  GET_OR_DISTINCT(GenericDINode, (Context, Tag, Header, DwarfOps)),
1252  NextMetadataNo);
1253  NextMetadataNo++;
1254  break;
1255  }
1256  case bitc::METADATA_SUBRANGE: {
1257  Metadata *Val = nullptr;
1258  // Operand 'count' is interpreted as:
1259  // - Signed integer (version 0)
1260  // - Metadata node (version 1)
1261  switch (Record[0] >> 1) {
1262  case 0:
1264  (Context, Record[1], unrotateSign(Record.back())));
1265  break;
1266  case 1:
1267  Val = GET_OR_DISTINCT(DISubrange, (Context, getMDOrNull(Record[1]),
1268  unrotateSign(Record.back())));
1269  break;
1270  default:
1271  return error("Invalid record: Unsupported version of DISubrange");
1272  }
1273 
1274  MetadataList.assignValue(Val, NextMetadataNo);
1275  IsDistinct = Record[0] & 1;
1276  NextMetadataNo++;
1277  break;
1278  }
1280  if (Record.size() != 3)
1281  return error("Invalid record");
1282 
1283  IsDistinct = Record[0] & 1;
1284  bool IsUnsigned = Record[0] & 2;
1285  MetadataList.assignValue(
1286  GET_OR_DISTINCT(DIEnumerator, (Context, unrotateSign(Record[1]),
1287  IsUnsigned, getMDString(Record[2]))),
1288  NextMetadataNo);
1289  NextMetadataNo++;
1290  break;
1291  }
1293  if (Record.size() < 6 || Record.size() > 7)
1294  return error("Invalid record");
1295 
1296  IsDistinct = Record[0];
1297  DINode::DIFlags Flags = (Record.size() > 6) ?
1298  static_cast<DINode::DIFlags>(Record[6]) : DINode::FlagZero;
1299 
1300  MetadataList.assignValue(
1302  (Context, Record[1], getMDString(Record[2]), Record[3],
1303  Record[4], Record[5], Flags)),
1304  NextMetadataNo);
1305  NextMetadataNo++;
1306  break;
1307  }
1309  if (Record.size() < 12 || Record.size() > 13)
1310  return error("Invalid record");
1311 
1312  // DWARF address space is encoded as N->getDWARFAddressSpace() + 1. 0 means
1313  // that there is no DWARF address space associated with DIDerivedType.
1314  Optional<unsigned> DWARFAddressSpace;
1315  if (Record.size() > 12 && Record[12])
1316  DWARFAddressSpace = Record[12] - 1;
1317 
1318  IsDistinct = Record[0];
1319  DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]);
1320  MetadataList.assignValue(
1322  (Context, Record[1], getMDString(Record[2]),
1323  getMDOrNull(Record[3]), Record[4],
1324  getDITypeRefOrNull(Record[5]),
1325  getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1326  Record[9], DWARFAddressSpace, Flags,
1327  getDITypeRefOrNull(Record[11]))),
1328  NextMetadataNo);
1329  NextMetadataNo++;
1330  break;
1331  }
1333  if (Record.size() < 16 || Record.size() > 17)
1334  return error("Invalid record");
1335 
1336  // If we have a UUID and this is not a forward declaration, lookup the
1337  // mapping.
1338  IsDistinct = Record[0] & 0x1;
1339  bool IsNotUsedInTypeRef = Record[0] >= 2;
1340  unsigned Tag = Record[1];
1341  MDString *Name = getMDString(Record[2]);
1342  Metadata *File = getMDOrNull(Record[3]);
1343  unsigned Line = Record[4];
1344  Metadata *Scope = getDITypeRefOrNull(Record[5]);
1345  Metadata *BaseType = nullptr;
1346  uint64_t SizeInBits = Record[7];
1347  if (Record[8] > (uint64_t)std::numeric_limits<uint32_t>::max())
1348  return error("Alignment value is too large");
1349  uint32_t AlignInBits = Record[8];
1350  uint64_t OffsetInBits = 0;
1351  DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]);
1352  Metadata *Elements = nullptr;
1353  unsigned RuntimeLang = Record[12];
1354  Metadata *VTableHolder = nullptr;
1355  Metadata *TemplateParams = nullptr;
1356  Metadata *Discriminator = nullptr;
1357  auto *Identifier = getMDString(Record[15]);
1358  // If this module is being parsed so that it can be ThinLTO imported
1359  // into another module, composite types only need to be imported
1360  // as type declarations (unless full type definitions requested).
1361  // Create type declarations up front to save memory. Also, buildODRType
1362  // handles the case where this is type ODRed with a definition needed
1363  // by the importing module, in which case the existing definition is
1364  // used.
1365  if (IsImporting && !ImportFullTypeDefinitions && Identifier &&
1366  (Tag == dwarf::DW_TAG_enumeration_type ||
1367  Tag == dwarf::DW_TAG_class_type ||
1368  Tag == dwarf::DW_TAG_structure_type ||
1369  Tag == dwarf::DW_TAG_union_type)) {
1370  Flags = Flags | DINode::FlagFwdDecl;
1371  } else {
1372  BaseType = getDITypeRefOrNull(Record[6]);
1373  OffsetInBits = Record[9];
1374  Elements = getMDOrNull(Record[11]);
1375  VTableHolder = getDITypeRefOrNull(Record[13]);
1376  TemplateParams = getMDOrNull(Record[14]);
1377  if (Record.size() > 16)
1378  Discriminator = getMDOrNull(Record[16]);
1379  }
1380  DICompositeType *CT = nullptr;
1381  if (Identifier)
1383  Context, *Identifier, Tag, Name, File, Line, Scope, BaseType,
1384  SizeInBits, AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
1385  VTableHolder, TemplateParams, Discriminator);
1386 
1387  // Create a node if we didn't get a lazy ODR type.
1388  if (!CT)
1390  (Context, Tag, Name, File, Line, Scope, BaseType,
1391  SizeInBits, AlignInBits, OffsetInBits, Flags,
1392  Elements, RuntimeLang, VTableHolder, TemplateParams,
1393  Identifier, Discriminator));
1394  if (!IsNotUsedInTypeRef && Identifier)
1395  MetadataList.addTypeRef(*Identifier, *cast<DICompositeType>(CT));
1396 
1397  MetadataList.assignValue(CT, NextMetadataNo);
1398  NextMetadataNo++;
1399  break;
1400  }
1402  if (Record.size() < 3 || Record.size() > 4)
1403  return error("Invalid record");
1404  bool IsOldTypeRefArray = Record[0] < 2;
1405  unsigned CC = (Record.size() > 3) ? Record[3] : 0;
1406 
1407  IsDistinct = Record[0] & 0x1;
1408  DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[1]);
1409  Metadata *Types = getMDOrNull(Record[2]);
1410  if (LLVM_UNLIKELY(IsOldTypeRefArray))
1411  Types = MetadataList.upgradeTypeRefArray(Types);
1412 
1413  MetadataList.assignValue(
1414  GET_OR_DISTINCT(DISubroutineType, (Context, Flags, CC, Types)),
1415  NextMetadataNo);
1416  NextMetadataNo++;
1417  break;
1418  }
1419 
1420  case bitc::METADATA_MODULE: {
1421  if (Record.size() != 6)
1422  return error("Invalid record");
1423 
1424  IsDistinct = Record[0];
1425  MetadataList.assignValue(
1427  (Context, getMDOrNull(Record[1]),
1428  getMDString(Record[2]), getMDString(Record[3]),
1429  getMDString(Record[4]), getMDString(Record[5]))),
1430  NextMetadataNo);
1431  NextMetadataNo++;
1432  break;
1433  }
1434 
1435  case bitc::METADATA_FILE: {
1436  if (Record.size() != 3 && Record.size() != 5 && Record.size() != 6)
1437  return error("Invalid record");
1438 
1439  IsDistinct = Record[0];
1441  // The BitcodeWriter writes null bytes into Record[3:4] when the Checksum
1442  // is not present. This matches up with the old internal representation,
1443  // and the old encoding for CSK_None in the ChecksumKind. The new
1444  // representation reserves the value 0 in the ChecksumKind to continue to
1445  // encode None in a backwards-compatible way.
1446  if (Record.size() > 4 && Record[3] && Record[4])
1447  Checksum.emplace(static_cast<DIFile::ChecksumKind>(Record[3]),
1448  getMDString(Record[4]));
1449  MetadataList.assignValue(
1451  DIFile,
1452  (Context, getMDString(Record[1]), getMDString(Record[2]), Checksum,
1453  Record.size() > 5 ? Optional<MDString *>(getMDString(Record[5]))
1454  : None)),
1455  NextMetadataNo);
1456  NextMetadataNo++;
1457  break;
1458  }
1460  if (Record.size() < 14 || Record.size() > 19)
1461  return error("Invalid record");
1462 
1463  // Ignore Record[0], which indicates whether this compile unit is
1464  // distinct. It's always distinct.
1465  IsDistinct = true;
1467  Context, Record[1], getMDOrNull(Record[2]), getMDString(Record[3]),
1468  Record[4], getMDString(Record[5]), Record[6], getMDString(Record[7]),
1469  Record[8], getMDOrNull(Record[9]), getMDOrNull(Record[10]),
1470  getMDOrNull(Record[12]), getMDOrNull(Record[13]),
1471  Record.size() <= 15 ? nullptr : getMDOrNull(Record[15]),
1472  Record.size() <= 14 ? 0 : Record[14],
1473  Record.size() <= 16 ? true : Record[16],
1474  Record.size() <= 17 ? false : Record[17],
1475  Record.size() <= 18 ? 0 : Record[18],
1476  Record.size() <= 19 ? 0 : Record[19]);
1477 
1478  MetadataList.assignValue(CU, NextMetadataNo);
1479  NextMetadataNo++;
1480 
1481  // Move the Upgrade the list of subprograms.
1482  if (Metadata *SPs = getMDOrNullWithoutPlaceholders(Record[11]))
1483  CUSubprograms.push_back({CU, SPs});
1484  break;
1485  }
1487  if (Record.size() < 18 || Record.size() > 21)
1488  return error("Invalid record");
1489 
1490  bool HasSPFlags = Record[0] & 4;
1491 
1492  DINode::DIFlags Flags;
1493  DISubprogram::DISPFlags SPFlags;
1494  if (!HasSPFlags)
1495  Flags = static_cast<DINode::DIFlags>(Record[11 + 2]);
1496  else {
1497  Flags = static_cast<DINode::DIFlags>(Record[11]);
1498  SPFlags = static_cast<DISubprogram::DISPFlags>(Record[9]);
1499  }
1500 
1501  // Support for old metadata when
1502  // subprogram specific flags are placed in DIFlags.
1503  const unsigned DIFlagMainSubprogram = 1 << 21;
1504  bool HasOldMainSubprogramFlag = Flags & DIFlagMainSubprogram;
1505  if (HasOldMainSubprogramFlag)
1506  // Remove old DIFlagMainSubprogram from DIFlags.
1507  // Note: This assumes that any future use of bit 21 defaults to it
1508  // being 0.
1509  Flags &= ~static_cast<DINode::DIFlags>(DIFlagMainSubprogram);
1510 
1511  if (HasOldMainSubprogramFlag && HasSPFlags)
1512  SPFlags |= DISubprogram::SPFlagMainSubprogram;
1513  else if (!HasSPFlags)
1514  SPFlags = DISubprogram::toSPFlags(
1515  /*IsLocalToUnit=*/Record[7], /*IsDefinition=*/Record[8],
1516  /*IsOptimized=*/Record[14], /*Virtuality=*/Record[11],
1517  /*DIFlagMainSubprogram*/HasOldMainSubprogramFlag);
1518 
1519  // All definitions should be distinct.
1520  IsDistinct = (Record[0] & 1) || (SPFlags & DISubprogram::SPFlagDefinition);
1521  // Version 1 has a Function as Record[15].
1522  // Version 2 has removed Record[15].
1523  // Version 3 has the Unit as Record[15].
1524  // Version 4 added thisAdjustment.
1525  // Version 5 repacked flags into DISPFlags, changing many element numbers.
1526  bool HasUnit = Record[0] & 2;
1527  if (!HasSPFlags && HasUnit && Record.size() < 19)
1528  return error("Invalid record");
1529  if (HasSPFlags && !HasUnit)
1530  return error("Invalid record");
1531  // Accommodate older formats.
1532  bool HasFn = false;
1533  bool HasThisAdj = true;
1534  bool HasThrownTypes = true;
1535  unsigned OffsetA = 0;
1536  unsigned OffsetB = 0;
1537  if (!HasSPFlags) {
1538  OffsetA = 2;
1539  OffsetB = 2;
1540  if (Record.size() >= 19) {
1541  HasFn = !HasUnit;
1542  OffsetB++;
1543  }
1544  HasThisAdj = Record.size() >= 20;
1545  HasThrownTypes = Record.size() >= 21;
1546  }
1547  Metadata *CUorFn = getMDOrNull(Record[12 + OffsetB]);
1549  DISubprogram,
1550  (Context,
1551  getDITypeRefOrNull(Record[1]), // scope
1552  getMDString(Record[2]), // name
1553  getMDString(Record[3]), // linkageName
1554  getMDOrNull(Record[4]), // file
1555  Record[5], // line
1556  getMDOrNull(Record[6]), // type
1557  Record[7 + OffsetA], // scopeLine
1558  getDITypeRefOrNull(Record[8 + OffsetA]), // containingType
1559  Record[10 + OffsetA], // virtualIndex
1560  HasThisAdj ? Record[16 + OffsetB] : 0, // thisAdjustment
1561  Flags, // flags
1562  SPFlags, // SPFlags
1563  HasUnit ? CUorFn : nullptr, // unit
1564  getMDOrNull(Record[13 + OffsetB]), // templateParams
1565  getMDOrNull(Record[14 + OffsetB]), // declaration
1566  getMDOrNull(Record[15 + OffsetB]), // retainedNodes
1567  HasThrownTypes ? getMDOrNull(Record[17 + OffsetB])
1568  : nullptr // thrownTypes
1569  ));
1570  MetadataList.assignValue(SP, NextMetadataNo);
1571  NextMetadataNo++;
1572 
1573  // Upgrade sp->function mapping to function->sp mapping.
1574  if (HasFn) {
1575  if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(CUorFn))
1576  if (auto *F = dyn_cast<Function>(CMD->getValue())) {
1577  if (F->isMaterializable())
1578  // Defer until materialized; unmaterialized functions may not have
1579  // metadata.
1580  FunctionsWithSPs[F] = SP;
1581  else if (!F->empty())
1582  F->setSubprogram(SP);
1583  }
1584  }
1585  break;
1586  }
1588  if (Record.size() != 5)
1589  return error("Invalid record");
1590 
1591  IsDistinct = Record[0];
1592  MetadataList.assignValue(
1594  (Context, getMDOrNull(Record[1]),
1595  getMDOrNull(Record[2]), Record[3], Record[4])),
1596  NextMetadataNo);
1597  NextMetadataNo++;
1598  break;
1599  }
1601  if (Record.size() != 4)
1602  return error("Invalid record");
1603 
1604  IsDistinct = Record[0];
1605  MetadataList.assignValue(
1607  (Context, getMDOrNull(Record[1]),
1608  getMDOrNull(Record[2]), Record[3])),
1609  NextMetadataNo);
1610  NextMetadataNo++;
1611  break;
1612  }
1614  IsDistinct = Record[0] & 1;
1615  MetadataList.assignValue(
1617  (Context, getMDOrNull(Record[1]),
1618  getMDOrNull(Record[2]), getMDString(Record[3]),
1619  getMDOrNull(Record[4]), Record[5])),
1620  NextMetadataNo);
1621  NextMetadataNo++;
1622  break;
1623  }
1624  case bitc::METADATA_NAMESPACE: {
1625  // Newer versions of DINamespace dropped file and line.
1626  MDString *Name;
1627  if (Record.size() == 3)
1628  Name = getMDString(Record[2]);
1629  else if (Record.size() == 5)
1630  Name = getMDString(Record[3]);
1631  else
1632  return error("Invalid record");
1633 
1634  IsDistinct = Record[0] & 1;
1635  bool ExportSymbols = Record[0] & 2;
1636  MetadataList.assignValue(
1638  (Context, getMDOrNull(Record[1]), Name, ExportSymbols)),
1639  NextMetadataNo);
1640  NextMetadataNo++;
1641  break;
1642  }
1643  case bitc::METADATA_MACRO: {
1644  if (Record.size() != 5)
1645  return error("Invalid record");
1646 
1647  IsDistinct = Record[0];
1648  MetadataList.assignValue(
1650  (Context, Record[1], Record[2], getMDString(Record[3]),
1651  getMDString(Record[4]))),
1652  NextMetadataNo);
1653  NextMetadataNo++;
1654  break;
1655  }
1657  if (Record.size() != 5)
1658  return error("Invalid record");
1659 
1660  IsDistinct = Record[0];
1661  MetadataList.assignValue(
1663  (Context, Record[1], Record[2], getMDOrNull(Record[3]),
1664  getMDOrNull(Record[4]))),
1665  NextMetadataNo);
1666  NextMetadataNo++;
1667  break;
1668  }
1670  if (Record.size() != 3)
1671  return error("Invalid record");
1672 
1673  IsDistinct = Record[0];
1674  MetadataList.assignValue(GET_OR_DISTINCT(DITemplateTypeParameter,
1675  (Context, getMDString(Record[1]),
1676  getDITypeRefOrNull(Record[2]))),
1677  NextMetadataNo);
1678  NextMetadataNo++;
1679  break;
1680  }
1682  if (Record.size() != 5)
1683  return error("Invalid record");
1684 
1685  IsDistinct = Record[0];
1686  MetadataList.assignValue(
1688  (Context, Record[1], getMDString(Record[2]),
1689  getDITypeRefOrNull(Record[3]),
1690  getMDOrNull(Record[4]))),
1691  NextMetadataNo);
1692  NextMetadataNo++;
1693  break;
1694  }
1696  if (Record.size() < 11 || Record.size() > 13)
1697  return error("Invalid record");
1698 
1699  IsDistinct = Record[0] & 1;
1700  unsigned Version = Record[0] >> 1;
1701 
1702  if (Version == 2) {
1703  MetadataList.assignValue(
1706  (Context, getMDOrNull(Record[1]), getMDString(Record[2]),
1707  getMDString(Record[3]), getMDOrNull(Record[4]), Record[5],
1708  getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1709  getMDOrNull(Record[9]), getMDOrNull(Record[10]), Record[11])),
1710  NextMetadataNo);
1711 
1712  NextMetadataNo++;
1713  } else if (Version == 1) {
1714  // No upgrade necessary. A null field will be introduced to indicate
1715  // that no parameter information is available.
1716  MetadataList.assignValue(
1718  (Context, getMDOrNull(Record[1]),
1719  getMDString(Record[2]), getMDString(Record[3]),
1720  getMDOrNull(Record[4]), Record[5],
1721  getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1722  getMDOrNull(Record[10]), nullptr, Record[11])),
1723  NextMetadataNo);
1724 
1725  NextMetadataNo++;
1726  } else if (Version == 0) {
1727  // Upgrade old metadata, which stored a global variable reference or a
1728  // ConstantInt here.
1729  NeedUpgradeToDIGlobalVariableExpression = true;
1730  Metadata *Expr = getMDOrNull(Record[9]);
1731  uint32_t AlignInBits = 0;
1732  if (Record.size() > 11) {
1733  if (Record[11] > (uint64_t)std::numeric_limits<uint32_t>::max())
1734  return error("Alignment value is too large");
1735  AlignInBits = Record[11];
1736  }
1737  GlobalVariable *Attach = nullptr;
1738  if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(Expr)) {
1739  if (auto *GV = dyn_cast<GlobalVariable>(CMD->getValue())) {
1740  Attach = GV;
1741  Expr = nullptr;
1742  } else if (auto *CI = dyn_cast<ConstantInt>(CMD->getValue())) {
1743  Expr = DIExpression::get(Context,
1744  {dwarf::DW_OP_constu, CI->getZExtValue(),
1745  dwarf::DW_OP_stack_value});
1746  } else {
1747  Expr = nullptr;
1748  }
1749  }
1752  (Context, getMDOrNull(Record[1]), getMDString(Record[2]),
1753  getMDString(Record[3]), getMDOrNull(Record[4]), Record[5],
1754  getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1755  getMDOrNull(Record[10]), nullptr, AlignInBits));
1756 
1757  DIGlobalVariableExpression *DGVE = nullptr;
1758  if (Attach || Expr)
1760  Context, DGV, Expr ? Expr : DIExpression::get(Context, {}));
1761  if (Attach)
1762  Attach->addDebugInfo(DGVE);
1763 
1764  auto *MDNode = Expr ? cast<Metadata>(DGVE) : cast<Metadata>(DGV);
1765  MetadataList.assignValue(MDNode, NextMetadataNo);
1766  NextMetadataNo++;
1767  } else
1768  return error("Invalid record");
1769 
1770  break;
1771  }
1772  case bitc::METADATA_LOCAL_VAR: {
1773  // 10th field is for the obseleted 'inlinedAt:' field.
1774  if (Record.size() < 8 || Record.size() > 10)
1775  return error("Invalid record");
1776 
1777  IsDistinct = Record[0] & 1;
1778  bool HasAlignment = Record[0] & 2;
1779  // 2nd field used to be an artificial tag, either DW_TAG_auto_variable or
1780  // DW_TAG_arg_variable, if we have alignment flag encoded it means, that
1781  // this is newer version of record which doesn't have artificial tag.
1782  bool HasTag = !HasAlignment && Record.size() > 8;
1783  DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[7 + HasTag]);
1784  uint32_t AlignInBits = 0;
1785  if (HasAlignment) {
1786  if (Record[8 + HasTag] > (uint64_t)std::numeric_limits<uint32_t>::max())
1787  return error("Alignment value is too large");
1788  AlignInBits = Record[8 + HasTag];
1789  }
1790  MetadataList.assignValue(
1792  (Context, getMDOrNull(Record[1 + HasTag]),
1793  getMDString(Record[2 + HasTag]),
1794  getMDOrNull(Record[3 + HasTag]), Record[4 + HasTag],
1795  getDITypeRefOrNull(Record[5 + HasTag]),
1796  Record[6 + HasTag], Flags, AlignInBits)),
1797  NextMetadataNo);
1798  NextMetadataNo++;
1799  break;
1800  }
1801  case bitc::METADATA_LABEL: {
1802  if (Record.size() != 5)
1803  return error("Invalid record");
1804 
1805  IsDistinct = Record[0] & 1;
1806  MetadataList.assignValue(
1808  (Context, getMDOrNull(Record[1]),
1809  getMDString(Record[2]),
1810  getMDOrNull(Record[3]), Record[4])),
1811  NextMetadataNo);
1812  NextMetadataNo++;
1813  break;
1814  }
1816  if (Record.size() < 1)
1817  return error("Invalid record");
1818 
1819  IsDistinct = Record[0] & 1;
1820  uint64_t Version = Record[0] >> 1;
1821  auto Elts = MutableArrayRef<uint64_t>(Record).slice(1);
1822 
1823  SmallVector<uint64_t, 6> Buffer;
1824  if (Error Err = upgradeDIExpression(Version, Elts, Buffer))
1825  return Err;
1826 
1827  MetadataList.assignValue(
1828  GET_OR_DISTINCT(DIExpression, (Context, Elts)), NextMetadataNo);
1829  NextMetadataNo++;
1830  break;
1831  }
1833  if (Record.size() != 3)
1834  return error("Invalid record");
1835 
1836  IsDistinct = Record[0];
1837  Metadata *Expr = getMDOrNull(Record[2]);
1838  if (!Expr)
1839  Expr = DIExpression::get(Context, {});
1840  MetadataList.assignValue(
1842  (Context, getMDOrNull(Record[1]), Expr)),
1843  NextMetadataNo);
1844  NextMetadataNo++;
1845  break;
1846  }
1848  if (Record.size() != 8)
1849  return error("Invalid record");
1850 
1851  IsDistinct = Record[0];
1852  MetadataList.assignValue(
1854  (Context, getMDString(Record[1]),
1855  getMDOrNull(Record[2]), Record[3],
1856  getMDString(Record[4]), getMDString(Record[5]),
1857  Record[6], getDITypeRefOrNull(Record[7]))),
1858  NextMetadataNo);
1859  NextMetadataNo++;
1860  break;
1861  }
1863  if (Record.size() != 6 && Record.size() != 7)
1864  return error("Invalid record");
1865 
1866  IsDistinct = Record[0];
1867  bool HasFile = (Record.size() == 7);
1868  MetadataList.assignValue(
1870  (Context, Record[1], getMDOrNull(Record[2]),
1871  getDITypeRefOrNull(Record[3]),
1872  HasFile ? getMDOrNull(Record[6]) : nullptr,
1873  HasFile ? Record[4] : 0, getMDString(Record[5]))),
1874  NextMetadataNo);
1875  NextMetadataNo++;
1876  break;
1877  }
1879  std::string String(Record.begin(), Record.end());
1880 
1881  // Test for upgrading !llvm.loop.
1882  HasSeenOldLoopTags |= mayBeOldLoopAttachmentTag(String);
1883  ++NumMDStringLoaded;
1884  Metadata *MD = MDString::get(Context, String);
1885  MetadataList.assignValue(MD, NextMetadataNo);
1886  NextMetadataNo++;
1887  break;
1888  }
1889  case bitc::METADATA_STRINGS: {
1890  auto CreateNextMDString = [&](StringRef Str) {
1891  ++NumMDStringLoaded;
1892  MetadataList.assignValue(MDString::get(Context, Str), NextMetadataNo);
1893  NextMetadataNo++;
1894  };
1895  if (Error Err = parseMetadataStrings(Record, Blob, CreateNextMDString))
1896  return Err;
1897  break;
1898  }
1900  if (Record.size() % 2 == 0)
1901  return error("Invalid record");
1902  unsigned ValueID = Record[0];
1903  if (ValueID >= ValueList.size())
1904  return error("Invalid record");
1905  if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID]))
1906  if (Error Err = parseGlobalObjectAttachment(
1907  *GO, ArrayRef<uint64_t>(Record).slice(1)))
1908  return Err;
1909  break;
1910  }
1911  case bitc::METADATA_KIND: {
1912  // Support older bitcode files that had METADATA_KIND records in a
1913  // block with METADATA_BLOCK_ID.
1914  if (Error Err = parseMetadataKindRecord(Record))
1915  return Err;
1916  break;
1917  }
1918  }
1919  return Error::success();
1920 #undef GET_OR_DISTINCT
1921 }
1922 
1923 Error MetadataLoader::MetadataLoaderImpl::parseMetadataStrings(
1924  ArrayRef<uint64_t> Record, StringRef Blob,
1925  function_ref<void(StringRef)> CallBack) {
1926  // All the MDStrings in the block are emitted together in a single
1927  // record. The strings are concatenated and stored in a blob along with
1928  // their sizes.
1929  if (Record.size() != 2)
1930  return error("Invalid record: metadata strings layout");
1931 
1932  unsigned NumStrings = Record[0];
1933  unsigned StringsOffset = Record[1];
1934  if (!NumStrings)
1935  return error("Invalid record: metadata strings with no strings");
1936  if (StringsOffset > Blob.size())
1937  return error("Invalid record: metadata strings corrupt offset");
1938 
1939  StringRef Lengths = Blob.slice(0, StringsOffset);
1940  SimpleBitstreamCursor R(Lengths);
1941 
1942  StringRef Strings = Blob.drop_front(StringsOffset);
1943  do {
1944  if (R.AtEndOfStream())
1945  return error("Invalid record: metadata strings bad length");
1946 
1947  Expected<uint32_t> MaybeSize = R.ReadVBR(6);
1948  if (!MaybeSize)
1949  return MaybeSize.takeError();
1950  uint32_t Size = MaybeSize.get();
1951  if (Strings.size() < Size)
1952  return error("Invalid record: metadata strings truncated chars");
1953 
1954  CallBack(Strings.slice(0, Size));
1955  Strings = Strings.drop_front(Size);
1956  } while (--NumStrings);
1957 
1958  return Error::success();
1959 }
1960 
1961 Error MetadataLoader::MetadataLoaderImpl::parseGlobalObjectAttachment(
1962  GlobalObject &GO, ArrayRef<uint64_t> Record) {
1963  assert(Record.size() % 2 == 0);
1964  for (unsigned I = 0, E = Record.size(); I != E; I += 2) {
1965  auto K = MDKindMap.find(Record[I]);
1966  if (K == MDKindMap.end())
1967  return error("Invalid ID");
1968  MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[I + 1]);
1969  if (!MD)
1970  return error("Invalid metadata attachment: expect fwd ref to MDNode");
1971  GO.addMetadata(K->second, *MD);
1972  }
1973  return Error::success();
1974 }
1975 
1976 /// Parse metadata attachments.
1978  Function &F, const SmallVectorImpl<Instruction *> &InstructionList) {
1980  return Err;
1981 
1983  PlaceholderQueue Placeholders;
1984 
1985  while (true) {
1986  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
1987  if (!MaybeEntry)
1988  return MaybeEntry.takeError();
1989  BitstreamEntry Entry = MaybeEntry.get();
1990 
1991  switch (Entry.Kind) {
1992  case BitstreamEntry::SubBlock: // Handled for us already.
1993  case BitstreamEntry::Error:
1994  return error("Malformed block");
1996  resolveForwardRefsAndPlaceholders(Placeholders);
1997  return Error::success();
1999  // The interesting case.
2000  break;
2001  }
2002 
2003  // Read a metadata attachment record.
2004  Record.clear();
2005  ++NumMDRecordLoaded;
2006  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
2007  if (!MaybeRecord)
2008  return MaybeRecord.takeError();
2009  switch (MaybeRecord.get()) {
2010  default: // Default behavior: ignore.
2011  break;
2013  unsigned RecordLength = Record.size();
2014  if (Record.empty())
2015  return error("Invalid record");
2016  if (RecordLength % 2 == 0) {
2017  // A function attachment.
2018  if (Error Err = parseGlobalObjectAttachment(F, Record))
2019  return Err;
2020  continue;
2021  }
2022 
2023  // An instruction attachment.
2024  Instruction *Inst = InstructionList[Record[0]];
2025  for (unsigned i = 1; i != RecordLength; i = i + 2) {
2026  unsigned Kind = Record[i];
2027  DenseMap<unsigned, unsigned>::iterator I = MDKindMap.find(Kind);
2028  if (I == MDKindMap.end())
2029  return error("Invalid ID");
2030  if (I->second == LLVMContext::MD_tbaa && StripTBAA)
2031  continue;
2032 
2033  auto Idx = Record[i + 1];
2034  if (Idx < (MDStringRef.size() + GlobalMetadataBitPosIndex.size()) &&
2035  !MetadataList.lookup(Idx)) {
2036  // Load the attachment if it is in the lazy-loadable range and hasn't
2037  // been loaded yet.
2038  lazyLoadOneMetadata(Idx, Placeholders);
2039  resolveForwardRefsAndPlaceholders(Placeholders);
2040  }
2041 
2042  Metadata *Node = MetadataList.getMetadataFwdRef(Idx);
2043  if (isa<LocalAsMetadata>(Node))
2044  // Drop the attachment. This used to be legal, but there's no
2045  // upgrade path.
2046  break;
2047  MDNode *MD = dyn_cast_or_null<MDNode>(Node);
2048  if (!MD)
2049  return error("Invalid metadata attachment");
2050 
2051  if (HasSeenOldLoopTags && I->second == LLVMContext::MD_loop)
2053 
2054  if (I->second == LLVMContext::MD_tbaa) {
2055  assert(!MD->isTemporary() && "should load MDs before attachments");
2056  MD = UpgradeTBAANode(*MD);
2057  }
2058  Inst->setMetadata(I->second, MD);
2059  }
2060  break;
2061  }
2062  }
2063  }
2064 }
2065 
2066 /// Parse a single METADATA_KIND record, inserting result in MDKindMap.
2067 Error MetadataLoader::MetadataLoaderImpl::parseMetadataKindRecord(
2068  SmallVectorImpl<uint64_t> &Record) {
2069  if (Record.size() < 2)
2070  return error("Invalid record");
2071 
2072  unsigned Kind = Record[0];
2073  SmallString<8> Name(Record.begin() + 1, Record.end());
2074 
2075  unsigned NewKind = TheModule.getMDKindID(Name.str());
2076  if (!MDKindMap.insert(std::make_pair(Kind, NewKind)).second)
2077  return error("Conflicting METADATA_KIND records");
2078  return Error::success();
2079 }
2080 
2081 /// Parse the metadata kinds out of the METADATA_KIND_BLOCK.
2084  return Err;
2085 
2087 
2088  // Read all the records.
2089  while (true) {
2090  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
2091  if (!MaybeEntry)
2092  return MaybeEntry.takeError();
2093  BitstreamEntry Entry = MaybeEntry.get();
2094 
2095  switch (Entry.Kind) {
2096  case BitstreamEntry::SubBlock: // Handled for us already.
2097  case BitstreamEntry::Error:
2098  return error("Malformed block");
2100  return Error::success();
2102  // The interesting case.
2103  break;
2104  }
2105 
2106  // Read a record.
2107  Record.clear();
2108  ++NumMDRecordLoaded;
2109  Expected<unsigned> MaybeCode = Stream.readRecord(Entry.ID, Record);
2110  if (!MaybeCode)
2111  return MaybeCode.takeError();
2112  switch (MaybeCode.get()) {
2113  default: // Default behavior: ignore.
2114  break;
2115  case bitc::METADATA_KIND: {
2116  if (Error Err = parseMetadataKindRecord(Record))
2117  return Err;
2118  break;
2119  }
2120  }
2121  }
2122 }
2123 
2125  Pimpl = std::move(RHS.Pimpl);
2126  return *this;
2127 }
2129  : Pimpl(std::move(RHS.Pimpl)) {}
2130 
2133  BitcodeReaderValueList &ValueList,
2134  bool IsImporting,
2135  std::function<Type *(unsigned)> getTypeByID)
2136  : Pimpl(std::make_unique<MetadataLoaderImpl>(
2137  Stream, TheModule, ValueList, std::move(getTypeByID), IsImporting)) {}
2138 
2139 Error MetadataLoader::parseMetadata(bool ModuleLevel) {
2140  return Pimpl->parseMetadata(ModuleLevel);
2141 }
2142 
2143 bool MetadataLoader::hasFwdRefs() const { return Pimpl->hasFwdRefs(); }
2144 
2145 /// Return the given metadata, creating a replaceable forward reference if
2146 /// necessary.
2148  return Pimpl->getMetadataFwdRefOrLoad(Idx);
2149 }
2150 
2152  return Pimpl->lookupSubprogramForFunction(F);
2153 }
2154 
2156  Function &F, const SmallVectorImpl<Instruction *> &InstructionList) {
2157  return Pimpl->parseMetadataAttachment(F, InstructionList);
2158 }
2159 
2161  return Pimpl->parseMetadataKinds();
2162 }
2163 
2164 void MetadataLoader::setStripTBAA(bool StripTBAA) {
2165  return Pimpl->setStripTBAA(StripTBAA);
2166 }
2167 
2168 bool MetadataLoader::isStrippingTBAA() { return Pimpl->isStrippingTBAA(); }
2169 
2170 unsigned MetadataLoader::size() const { return Pimpl->size(); }
2171 void MetadataLoader::shrinkTo(unsigned N) { return Pimpl->shrinkTo(N); }
2172 
2174  return Pimpl->upgradeDebugIntrinsics(F);
2175 }
uint64_t CallInst * C
bool mayBeOldLoopAttachmentTag(StringRef Name)
Check whether a string looks like an old loop attachment tag.
Definition: AutoUpgrade.h:83
bool isStrippingTBAA()
Return true if the Loader is stripping TBAA metadata.
reference emplace_back(ArgTypes &&... Args)
Definition: SmallVector.h:641
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1132
bool empty() const
Definition: Function.h:686
GCNRegPressure max(const GCNRegPressure &P1, const GCNRegPressure &P2)
If this flag is used, the advance() method does not automatically pop the block scope when the end of...
LLVMContext & Context
Atomic ordering constants.
bool isMetadataTy() const
Return true if this is &#39;metadata&#39;.
Definition: Type.h:190
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
This class represents lattice values for constants.
Definition: AllocatorList.h:23
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:65
#define LLVM_UNLIKELY(EXPR)
Definition: Compiler.h:204
#define LLVM_LIKELY(EXPR)
Definition: Compiler.h:203
unsigned size() const
amdgpu Simplify well known AMD library false FunctionCallee Value const Twine & Name
Tracking metadata reference.
Definition: TrackingMDRef.h:25
static MDString * get(LLVMContext &Context, StringRef Str)
Definition: Metadata.cpp:453
void addOperand(MDNode *M)
Definition: Metadata.cpp:1086
Expected< uint32_t > ReadVBR(unsigned NumBits)
void emplace(ArgTypes &&... Args)
Create a new object by constructing it in place with the given arguments.
Definition: Optional.h:237
static DISPFlags toSPFlags(bool IsLocalToUnit, bool IsDefinition, bool IsOptimized, unsigned Virtuality=SPFlagNonvirtual, bool IsMainSubprogram=false)
An efficient, type-erasing, non-owning reference to a callable.
Definition: STLExtras.h:104
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:259
STATISTIC(NumFunctions, "Total number of functions")
Metadata node.
Definition: Metadata.h:863
F(f)
block Block Frequency true
Error takeError()
Take ownership of the stored error.
Definition: Error.h:552
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:369
bool isForwardDecl() const
std::pair< iterator, bool > insert(const std::pair< KeyT, ValueT > &KV)
Definition: DenseMap.h:221
A tuple of MDNodes.
Definition: Metadata.h:1325
Definition: BitVector.h:937
std::string toString(Error E)
Write all error messages (if any) in E to a string.
Definition: Error.h:966
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:80
LLVM_NODISCARD 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:620
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...
Error SkipBlock()
Having read the ENTER_SUBBLOCK abbrevid and a BlockID, skip over the body of this block...
LLVM_NODISCARD StringRef slice(size_t Start, size_t End) const
Return a reference to the substring from [Start, End).
Definition: StringRef.h:679
static TempMDTuple getTemporary(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1177
Placeholder metadata for operands of distinct MDNodes.
Definition: Metadata.h:1280
Only used in LLVM metadata.
Definition: Dwarf.h:120
Tagged union holding either a T or a Error.
Definition: yaml2obj.h:21
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...
Expected< unsigned > ReadCode()
Subprogram description.
Expected< unsigned > skipRecord(unsigned AbbrevID)
Read the current record and discard it, returning the code for the record.
Error parseMetadata(bool ModuleLevel)
Parse a METADATA_BLOCK.
unsigned size() const
Definition: ValueList.h:64
Enumeration value.
NamedMDNode * getNamedMetadata(const Twine &Name) const
Return the first NamedMDNode in the module with the specified name.
Definition: Module.cpp:250
LLVM_NODISCARD size_t size() const
size - Get the string size.
Definition: StringRef.h:130
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.
Debug location.
iterator find(const_arg_type_t< KeyT > Val)
Definition: DenseMap.h:176
static MetadataAsValue * get(LLVMContext &Context, Metadata *MD)
Definition: Metadata.cpp:105
bool isVoidTy() const
Return true if this is &#39;void&#39;.
Definition: Type.h:140
static TempMDTuple getTemporary(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Return a temporary node.
Definition: Metadata.h:1152
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1165
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:432
void setSubprogram(DISubprogram *SP)
Set the attached subprogram.
Definition: Metadata.cpp:1500
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:290
Metadata * get() const
Definition: TrackingMDRef.h:57
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:64
Instrumentation for Order File
size_t size() const
size - Get the array size.
Definition: ArrayRef.h:148
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
This represents a position within a bitcode file, implemented on top of a SimpleBitstreamCursor.
static MDTuple * getDistinct(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1173
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:178
std::pair< llvm::MachO::Architecture, std::string > UUID
static LocalAsMetadata * get(Value *Local)
Definition: Metadata.h:435
void consumeError(Error Err)
Consume a Error without doing anything.
Definition: Error.h:981
Metadata * getMetadataFwdRefOrLoad(unsigned Idx)
Return the given metadata, creating a replaceable forward reference if necessary. ...
size_t size() const
Definition: SmallVector.h:52
void setMetadata(unsigned KindID, MDNode *Node)
Set the metadata of the specified kind to the specified node.
Definition: Metadata.cpp:1222
An imported module (C++ using directive or similar).
Error JumpToBit(uint64_t BitNo)
Reset the stream to the specified bit number.
Expected< unsigned > readRecord(unsigned AbbrevID, SmallVectorImpl< uint64_t > &Vals, StringRef *Blob=nullptr)
constexpr bool empty(const T &RangeOrContainer)
Test whether RangeOrContainer is empty. Similar to C++17 std::empty.
Definition: STLExtras.h:197
BaseType
A given derived pointer can have multiple base pointers through phi/selects.
static ErrorSuccess success()
Create a success value.
Definition: Error.h:326
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:1146
Helper class that handles loading Metadatas and keeping them available.
static Error error(const Twine &Message)
static ValueAsMetadata * get(Value *V)
Definition: Metadata.cpp:348
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:837
Module.h This file contains the declarations for the Module class.
void addMetadata(unsigned KindID, MDNode &MD)
Add a metadata attachment.
Definition: Metadata.cpp:1390
reference get()
Returns a reference to the stored T value.
Definition: Error.h:532
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:267
MDNode * UpgradeTBAANode(MDNode &TBAANode)
If the given TBAA tag uses the scalar TBAA format, create a new node corresponding to the upgrade to ...
Value * getValueFwdRef(unsigned Idx, Type *Ty, Type **FullTy=nullptr)
Definition: ValueList.cpp:119
A (clang) module that has been imported by the compile unit.
Error parseMetadataKinds()
Parse a METADATA_KIND block for the current module.
iterator begin() const
Definition: ArrayRef.h:330
Generic tagged DWARF-like metadata node.
static void clear(coro::Shape &Shape)
Definition: Coroutines.cpp:225
void append(in_iter in_start, in_iter in_end)
Add the specified range to the end of the SmallVector.
Definition: SmallVector.h:387
Type array for a subprogram.
Error EnterSubBlock(unsigned BlockID, unsigned *NumWordsP=nullptr)
Having read the ENTER_SUBBLOCK abbrevid, and enter the block.
DIFlags
Debug info flags.
MDString * getRawIdentifier() const
LLVM_NODISCARD bool empty() const
Definition: SmallVector.h:55
#define I(x, y, z)
Definition: MD5.cpp:58
#define N
iterator end()
Definition: DenseMap.h:108
Expected< BitstreamEntry > advanceSkippingSubblocks(unsigned Flags=0)
This is a convenience function for clients that don&#39;t expect any subblocks.
uint32_t Size
Definition: Profile.cpp:46
DISPFlags
Debug info subprogram flags.
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:211
MetadataLoader & operator=(MetadataLoader &&)
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::@158 Kind
#define LLVM_FALLTHROUGH
LLVM_FALLTHROUGH - Mark fallthrough cases in switch statements.
Definition: Compiler.h:265
Lightweight error class with error context and mandatory checking.
Definition: Error.h:157
iterator end() const
Definition: ArrayRef.h:331
bool isTemporary() const
Definition: Metadata.h:943
void addDebugInfo(DIGlobalVariableExpression *GV)
Attach a DIGlobalVariableExpression.
Definition: Metadata.cpp:1517
print Print MemDeps of function
iterator_range< global_iterator > globals()
Definition: Module.h:587
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
A single uniqued string.
Definition: Metadata.h:603
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:57
const uint64_t Version
Definition: InstrProf.h:984
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:344