1 //===- DebugInfo.cpp - Debug Information Helper Classes -------------------===//
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 // This file implements the helper classes used to build and interpret debug
11 // information in LLVM IR form.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm-c/DebugInfo.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/SmallPtrSet.h"
21 #include "llvm/ADT/SmallVector.h"
22 #include "llvm/ADT/StringRef.h"
23 #include "llvm/IR/BasicBlock.h"
24 #include "llvm/IR/Constants.h"
25 #include "llvm/IR/DebugInfoMetadata.h"
26 #include "llvm/IR/DebugLoc.h"
27 #include "llvm/IR/DebugInfo.h"
28 #include "llvm/IR/DIBuilder.h"
29 #include "llvm/IR/Function.h"
30 #include "llvm/IR/GVMaterializer.h"
31 #include "llvm/IR/Instruction.h"
32 #include "llvm/IR/IntrinsicInst.h"
33 #include "llvm/IR/LLVMContext.h"
34 #include "llvm/IR/Metadata.h"
35 #include "llvm/IR/Module.h"
36 #include "llvm/Support/Casting.h"
37 #include <algorithm>
38 #include <cassert>
39 #include <utility>
40 
41 using namespace llvm;
42 using namespace llvm::dwarf;
43 
44 DISubprogram *llvm::getDISubprogram(const MDNode *Scope) {
45   if (auto *LocalScope = dyn_cast_or_null<DILocalScope>(Scope))
46     return LocalScope->getSubprogram();
47   return nullptr;
48 }
49 
50 //===----------------------------------------------------------------------===//
51 // DebugInfoFinder implementations.
52 //===----------------------------------------------------------------------===//
53 
54 void DebugInfoFinder::reset() {
55   CUs.clear();
56   SPs.clear();
57   GVs.clear();
58   TYs.clear();
59   Scopes.clear();
60   NodesSeen.clear();
61 }
62 
63 void DebugInfoFinder::processModule(const Module &M) {
64   for (auto *CU : M.debug_compile_units())
65     processCompileUnit(CU);
66   for (auto &F : M.functions()) {
67     if (auto *SP = cast_or_null<DISubprogram>(F.getSubprogram()))
68       processSubprogram(SP);
69     // There could be subprograms from inlined functions referenced from
70     // instructions only. Walk the function to find them.
71     for (const BasicBlock &BB : F)
72       for (const Instruction &I : BB)
73         processInstruction(M, I);
74   }
75 }
76 
77 void DebugInfoFinder::processCompileUnit(DICompileUnit *CU) {
78   if (!addCompileUnit(CU))
79     return;
80   for (auto DIG : CU->getGlobalVariables()) {
81     if (!addGlobalVariable(DIG))
82       continue;
83     auto *GV = DIG->getVariable();
84     processScope(GV->getScope());
85     processType(GV->getType().resolve());
86   }
87   for (auto *ET : CU->getEnumTypes())
88     processType(ET);
89   for (auto *RT : CU->getRetainedTypes())
90     if (auto *T = dyn_cast<DIType>(RT))
91       processType(T);
92     else
93       processSubprogram(cast<DISubprogram>(RT));
94   for (auto *Import : CU->getImportedEntities()) {
95     auto *Entity = Import->getEntity().resolve();
96     if (auto *T = dyn_cast<DIType>(Entity))
97       processType(T);
98     else if (auto *SP = dyn_cast<DISubprogram>(Entity))
99       processSubprogram(SP);
100     else if (auto *NS = dyn_cast<DINamespace>(Entity))
101       processScope(NS->getScope());
102     else if (auto *M = dyn_cast<DIModule>(Entity))
103       processScope(M->getScope());
104   }
105 }
106 
107 void DebugInfoFinder::processInstruction(const Module &M,
108                                          const Instruction &I) {
109   if (auto *DDI = dyn_cast<DbgDeclareInst>(&I))
110     processDeclare(M, DDI);
111   else if (auto *DVI = dyn_cast<DbgValueInst>(&I))
112     processValue(M, DVI);
113 
114   if (auto DbgLoc = I.getDebugLoc())
115     processLocation(M, DbgLoc.get());
116 }
117 
118 void DebugInfoFinder::processLocation(const Module &M, const DILocation *Loc) {
119   if (!Loc)
120     return;
121   processScope(Loc->getScope());
122   processLocation(M, Loc->getInlinedAt());
123 }
124 
125 void DebugInfoFinder::processType(DIType *DT) {
126   if (!addType(DT))
127     return;
128   processScope(DT->getScope().resolve());
129   if (auto *ST = dyn_cast<DISubroutineType>(DT)) {
130     for (DITypeRef Ref : ST->getTypeArray())
131       processType(Ref.resolve());
132     return;
133   }
134   if (auto *DCT = dyn_cast<DICompositeType>(DT)) {
135     processType(DCT->getBaseType().resolve());
136     for (Metadata *D : DCT->getElements()) {
137       if (auto *T = dyn_cast<DIType>(D))
138         processType(T);
139       else if (auto *SP = dyn_cast<DISubprogram>(D))
140         processSubprogram(SP);
141     }
142     return;
143   }
144   if (auto *DDT = dyn_cast<DIDerivedType>(DT)) {
145     processType(DDT->getBaseType().resolve());
146   }
147 }
148 
149 void DebugInfoFinder::processScope(DIScope *Scope) {
150   if (!Scope)
151     return;
152   if (auto *Ty = dyn_cast<DIType>(Scope)) {
153     processType(Ty);
154     return;
155   }
156   if (auto *CU = dyn_cast<DICompileUnit>(Scope)) {
157     addCompileUnit(CU);
158     return;
159   }
160   if (auto *SP = dyn_cast<DISubprogram>(Scope)) {
161     processSubprogram(SP);
162     return;
163   }
164   if (!addScope(Scope))
165     return;
166   if (auto *LB = dyn_cast<DILexicalBlockBase>(Scope)) {
167     processScope(LB->getScope());
168   } else if (auto *NS = dyn_cast<DINamespace>(Scope)) {
169     processScope(NS->getScope());
170   } else if (auto *M = dyn_cast<DIModule>(Scope)) {
171     processScope(M->getScope());
172   }
173 }
174 
175 void DebugInfoFinder::processSubprogram(DISubprogram *SP) {
176   if (!addSubprogram(SP))
177     return;
178   processScope(SP->getScope().resolve());
179   // Some of the users, e.g. CloneFunctionInto / CloneModule, need to set up a
180   // ValueMap containing identity mappings for all of the DICompileUnit's, not
181   // just DISubprogram's, referenced from anywhere within the Function being
182   // cloned prior to calling MapMetadata / RemapInstruction to avoid their
183   // duplication later as DICompileUnit's are also directly referenced by
184   // llvm.dbg.cu list. Thefore we need to collect DICompileUnit's here as well.
185   // Also, DICompileUnit's may reference DISubprogram's too and therefore need
186   // to be at least looked through.
187   processCompileUnit(SP->getUnit());
188   processType(SP->getType());
189   for (auto *Element : SP->getTemplateParams()) {
190     if (auto *TType = dyn_cast<DITemplateTypeParameter>(Element)) {
191       processType(TType->getType().resolve());
192     } else if (auto *TVal = dyn_cast<DITemplateValueParameter>(Element)) {
193       processType(TVal->getType().resolve());
194     }
195   }
196 }
197 
198 void DebugInfoFinder::processDeclare(const Module &M,
199                                      const DbgDeclareInst *DDI) {
200   auto *N = dyn_cast<MDNode>(DDI->getVariable());
201   if (!N)
202     return;
203 
204   auto *DV = dyn_cast<DILocalVariable>(N);
205   if (!DV)
206     return;
207 
208   if (!NodesSeen.insert(DV).second)
209     return;
210   processScope(DV->getScope());
211   processType(DV->getType().resolve());
212 }
213 
214 void DebugInfoFinder::processValue(const Module &M, const DbgValueInst *DVI) {
215   auto *N = dyn_cast<MDNode>(DVI->getVariable());
216   if (!N)
217     return;
218 
219   auto *DV = dyn_cast<DILocalVariable>(N);
220   if (!DV)
221     return;
222 
223   if (!NodesSeen.insert(DV).second)
224     return;
225   processScope(DV->getScope());
226   processType(DV->getType().resolve());
227 }
228 
229 bool DebugInfoFinder::addType(DIType *DT) {
230   if (!DT)
231     return false;
232 
233   if (!NodesSeen.insert(DT).second)
234     return false;
235 
236   TYs.push_back(const_cast<DIType *>(DT));
237   return true;
238 }
239 
240 bool DebugInfoFinder::addCompileUnit(DICompileUnit *CU) {
241   if (!CU)
242     return false;
243   if (!NodesSeen.insert(CU).second)
244     return false;
245 
246   CUs.push_back(CU);
247   return true;
248 }
249 
250 bool DebugInfoFinder::addGlobalVariable(DIGlobalVariableExpression *DIG) {
251   if (!NodesSeen.insert(DIG).second)
252     return false;
253 
254   GVs.push_back(DIG);
255   return true;
256 }
257 
258 bool DebugInfoFinder::addSubprogram(DISubprogram *SP) {
259   if (!SP)
260     return false;
261 
262   if (!NodesSeen.insert(SP).second)
263     return false;
264 
265   SPs.push_back(SP);
266   return true;
267 }
268 
269 bool DebugInfoFinder::addScope(DIScope *Scope) {
270   if (!Scope)
271     return false;
272   // FIXME: Ocaml binding generates a scope with no content, we treat it
273   // as null for now.
274   if (Scope->getNumOperands() == 0)
275     return false;
276   if (!NodesSeen.insert(Scope).second)
277     return false;
278   Scopes.push_back(Scope);
279   return true;
280 }
281 
282 static MDNode *stripDebugLocFromLoopID(MDNode *N) {
283   assert(N->op_begin() != N->op_end() && "Missing self reference?");
284 
285   // if there is no debug location, we do not have to rewrite this MDNode.
286   if (std::none_of(N->op_begin() + 1, N->op_end(), [](const MDOperand &Op) {
287         return isa<DILocation>(Op.get());
288       }))
289     return N;
290 
291   // If there is only the debug location without any actual loop metadata, we
292   // can remove the metadata.
293   if (std::none_of(N->op_begin() + 1, N->op_end(), [](const MDOperand &Op) {
294         return !isa<DILocation>(Op.get());
295       }))
296     return nullptr;
297 
298   SmallVector<Metadata *, 4> Args;
299   // Reserve operand 0 for loop id self reference.
300   auto TempNode = MDNode::getTemporary(N->getContext(), None);
301   Args.push_back(TempNode.get());
302   // Add all non-debug location operands back.
303   for (auto Op = N->op_begin() + 1; Op != N->op_end(); Op++) {
304     if (!isa<DILocation>(*Op))
305       Args.push_back(*Op);
306   }
307 
308   // Set the first operand to itself.
309   MDNode *LoopID = MDNode::get(N->getContext(), Args);
310   LoopID->replaceOperandWith(0, LoopID);
311   return LoopID;
312 }
313 
314 bool llvm::stripDebugInfo(Function &F) {
315   bool Changed = false;
316   if (F.getMetadata(LLVMContext::MD_dbg)) {
317     Changed = true;
318     F.setSubprogram(nullptr);
319   }
320 
321   DenseMap<MDNode*, MDNode*> LoopIDsMap;
322   for (BasicBlock &BB : F) {
323     for (auto II = BB.begin(), End = BB.end(); II != End;) {
324       Instruction &I = *II++; // We may delete the instruction, increment now.
325       if (isa<DbgInfoIntrinsic>(&I)) {
326         I.eraseFromParent();
327         Changed = true;
328         continue;
329       }
330       if (I.getDebugLoc()) {
331         Changed = true;
332         I.setDebugLoc(DebugLoc());
333       }
334     }
335 
336     auto *TermInst = BB.getTerminator();
337     if (!TermInst)
338       // This is invalid IR, but we may not have run the verifier yet
339       continue;
340     if (auto *LoopID = TermInst->getMetadata(LLVMContext::MD_loop)) {
341       auto *NewLoopID = LoopIDsMap.lookup(LoopID);
342       if (!NewLoopID)
343         NewLoopID = LoopIDsMap[LoopID] = stripDebugLocFromLoopID(LoopID);
344       if (NewLoopID != LoopID)
345         TermInst->setMetadata(LLVMContext::MD_loop, NewLoopID);
346     }
347   }
348   return Changed;
349 }
350 
351 bool llvm::StripDebugInfo(Module &M) {
352   bool Changed = false;
353 
354   for (Module::named_metadata_iterator NMI = M.named_metadata_begin(),
355          NME = M.named_metadata_end(); NMI != NME;) {
356     NamedMDNode *NMD = &*NMI;
357     ++NMI;
358 
359     // We're stripping debug info, and without them, coverage information
360     // doesn't quite make sense.
361     if (NMD->getName().startswith("llvm.dbg.") ||
362         NMD->getName() == "llvm.gcov") {
363       NMD->eraseFromParent();
364       Changed = true;
365     }
366   }
367 
368   for (Function &F : M)
369     Changed |= stripDebugInfo(F);
370 
371   for (auto &GV : M.globals()) {
372     SmallVector<MDNode *, 1> MDs;
373     GV.getMetadata(LLVMContext::MD_dbg, MDs);
374     if (!MDs.empty()) {
375       GV.eraseMetadata(LLVMContext::MD_dbg);
376       Changed = true;
377     }
378   }
379 
380   if (GVMaterializer *Materializer = M.getMaterializer())
381     Materializer->setStripDebugInfo();
382 
383   return Changed;
384 }
385 
386 namespace {
387 
388 /// Helper class to downgrade -g metadata to -gline-tables-only metadata.
389 class DebugTypeInfoRemoval {
390   DenseMap<Metadata *, Metadata *> Replacements;
391 
392 public:
393   /// The (void)() type.
394   MDNode *EmptySubroutineType;
395 
396 private:
397   /// Remember what linkage name we originally had before stripping. If we end
398   /// up making two subprograms identical who originally had different linkage
399   /// names, then we need to make one of them distinct, to avoid them getting
400   /// uniqued. Maps the new node to the old linkage name.
401   DenseMap<DISubprogram *, StringRef> NewToLinkageName;
402 
403   // TODO: Remember the distinct subprogram we created for a given linkage name,
404   // so that we can continue to unique whenever possible. Map <newly created
405   // node, old linkage name> to the first (possibly distinct) mdsubprogram
406   // created for that combination. This is not strictly needed for correctness,
407   // but can cut down on the number of MDNodes and let us diff cleanly with the
408   // output of -gline-tables-only.
409 
410 public:
411   DebugTypeInfoRemoval(LLVMContext &C)
412       : EmptySubroutineType(DISubroutineType::get(C, DINode::FlagZero, 0,
413                                                   MDNode::get(C, {}))) {}
414 
415   Metadata *map(Metadata *M) {
416     if (!M)
417       return nullptr;
418     auto Replacement = Replacements.find(M);
419     if (Replacement != Replacements.end())
420       return Replacement->second;
421 
422     return M;
423   }
424   MDNode *mapNode(Metadata *N) { return dyn_cast_or_null<MDNode>(map(N)); }
425 
426   /// Recursively remap N and all its referenced children. Does a DF post-order
427   /// traversal, so as to remap bottoms up.
428   void traverseAndRemap(MDNode *N) { traverse(N); }
429 
430 private:
431   // Create a new DISubprogram, to replace the one given.
432   DISubprogram *getReplacementSubprogram(DISubprogram *MDS) {
433     auto *FileAndScope = cast_or_null<DIFile>(map(MDS->getFile()));
434     StringRef LinkageName = MDS->getName().empty() ? MDS->getLinkageName() : "";
435     DISubprogram *Declaration = nullptr;
436     auto *Type = cast_or_null<DISubroutineType>(map(MDS->getType()));
437     DITypeRef ContainingType(map(MDS->getContainingType()));
438     auto *Unit = cast_or_null<DICompileUnit>(map(MDS->getUnit()));
439     auto Variables = nullptr;
440     auto TemplateParams = nullptr;
441 
442     // Make a distinct DISubprogram, for situations that warrent it.
443     auto distinctMDSubprogram = [&]() {
444       return DISubprogram::getDistinct(
445           MDS->getContext(), FileAndScope, MDS->getName(), LinkageName,
446           FileAndScope, MDS->getLine(), Type, MDS->isLocalToUnit(),
447           MDS->isDefinition(), MDS->getScopeLine(), ContainingType,
448           MDS->getVirtuality(), MDS->getVirtualIndex(),
449           MDS->getThisAdjustment(), MDS->getFlags(), MDS->isOptimized(), Unit,
450           TemplateParams, Declaration, Variables);
451     };
452 
453     if (MDS->isDistinct())
454       return distinctMDSubprogram();
455 
456     auto *NewMDS = DISubprogram::get(
457         MDS->getContext(), FileAndScope, MDS->getName(), LinkageName,
458         FileAndScope, MDS->getLine(), Type, MDS->isLocalToUnit(),
459         MDS->isDefinition(), MDS->getScopeLine(), ContainingType,
460         MDS->getVirtuality(), MDS->getVirtualIndex(), MDS->getThisAdjustment(),
461         MDS->getFlags(), MDS->isOptimized(), Unit, TemplateParams, Declaration,
462         Variables);
463 
464     StringRef OldLinkageName = MDS->getLinkageName();
465 
466     // See if we need to make a distinct one.
467     auto OrigLinkage = NewToLinkageName.find(NewMDS);
468     if (OrigLinkage != NewToLinkageName.end()) {
469       if (OrigLinkage->second == OldLinkageName)
470         // We're good.
471         return NewMDS;
472 
473       // Otherwise, need to make a distinct one.
474       // TODO: Query the map to see if we already have one.
475       return distinctMDSubprogram();
476     }
477 
478     NewToLinkageName.insert({NewMDS, MDS->getLinkageName()});
479     return NewMDS;
480   }
481 
482   /// Create a new compile unit, to replace the one given
483   DICompileUnit *getReplacementCU(DICompileUnit *CU) {
484     // Drop skeleton CUs.
485     if (CU->getDWOId())
486       return nullptr;
487 
488     auto *File = cast_or_null<DIFile>(map(CU->getFile()));
489     MDTuple *EnumTypes = nullptr;
490     MDTuple *RetainedTypes = nullptr;
491     MDTuple *GlobalVariables = nullptr;
492     MDTuple *ImportedEntities = nullptr;
493     return DICompileUnit::getDistinct(
494         CU->getContext(), CU->getSourceLanguage(), File, CU->getProducer(),
495         CU->isOptimized(), CU->getFlags(), CU->getRuntimeVersion(),
496         CU->getSplitDebugFilename(), DICompileUnit::LineTablesOnly, EnumTypes,
497         RetainedTypes, GlobalVariables, ImportedEntities, CU->getMacros(),
498         CU->getDWOId(), CU->getSplitDebugInlining(),
499         CU->getDebugInfoForProfiling(), CU->getGnuPubnames());
500   }
501 
502   DILocation *getReplacementMDLocation(DILocation *MLD) {
503     auto *Scope = map(MLD->getScope());
504     auto *InlinedAt = map(MLD->getInlinedAt());
505     if (MLD->isDistinct())
506       return DILocation::getDistinct(MLD->getContext(), MLD->getLine(),
507                                      MLD->getColumn(), Scope, InlinedAt);
508     return DILocation::get(MLD->getContext(), MLD->getLine(), MLD->getColumn(),
509                            Scope, InlinedAt);
510   }
511 
512   /// Create a new generic MDNode, to replace the one given
513   MDNode *getReplacementMDNode(MDNode *N) {
514     SmallVector<Metadata *, 8> Ops;
515     Ops.reserve(N->getNumOperands());
516     for (auto &I : N->operands())
517       if (I)
518         Ops.push_back(map(I));
519     auto *Ret = MDNode::get(N->getContext(), Ops);
520     return Ret;
521   }
522 
523   /// Attempt to re-map N to a newly created node.
524   void remap(MDNode *N) {
525     if (Replacements.count(N))
526       return;
527 
528     auto doRemap = [&](MDNode *N) -> MDNode * {
529       if (!N)
530         return nullptr;
531       if (auto *MDSub = dyn_cast<DISubprogram>(N)) {
532         remap(MDSub->getUnit());
533         return getReplacementSubprogram(MDSub);
534       }
535       if (isa<DISubroutineType>(N))
536         return EmptySubroutineType;
537       if (auto *CU = dyn_cast<DICompileUnit>(N))
538         return getReplacementCU(CU);
539       if (isa<DIFile>(N))
540         return N;
541       if (auto *MDLB = dyn_cast<DILexicalBlockBase>(N))
542         // Remap to our referenced scope (recursively).
543         return mapNode(MDLB->getScope());
544       if (auto *MLD = dyn_cast<DILocation>(N))
545         return getReplacementMDLocation(MLD);
546 
547       // Otherwise, if we see these, just drop them now. Not strictly necessary,
548       // but this speeds things up a little.
549       if (isa<DINode>(N))
550         return nullptr;
551 
552       return getReplacementMDNode(N);
553     };
554     Replacements[N] = doRemap(N);
555   }
556 
557   /// Do the remapping traversal.
558   void traverse(MDNode *);
559 };
560 
561 } // end anonymous namespace
562 
563 void DebugTypeInfoRemoval::traverse(MDNode *N) {
564   if (!N || Replacements.count(N))
565     return;
566 
567   // To avoid cycles, as well as for efficiency sake, we will sometimes prune
568   // parts of the graph.
569   auto prune = [](MDNode *Parent, MDNode *Child) {
570     if (auto *MDS = dyn_cast<DISubprogram>(Parent))
571       return Child == MDS->getRetainedNodes().get();
572     return false;
573   };
574 
575   SmallVector<MDNode *, 16> ToVisit;
576   DenseSet<MDNode *> Opened;
577 
578   // Visit each node starting at N in post order, and map them.
579   ToVisit.push_back(N);
580   while (!ToVisit.empty()) {
581     auto *N = ToVisit.back();
582     if (!Opened.insert(N).second) {
583       // Close it.
584       remap(N);
585       ToVisit.pop_back();
586       continue;
587     }
588     for (auto &I : N->operands())
589       if (auto *MDN = dyn_cast_or_null<MDNode>(I))
590         if (!Opened.count(MDN) && !Replacements.count(MDN) && !prune(N, MDN) &&
591             !isa<DICompileUnit>(MDN))
592           ToVisit.push_back(MDN);
593   }
594 }
595 
596 bool llvm::stripNonLineTableDebugInfo(Module &M) {
597   bool Changed = false;
598 
599   // First off, delete the debug intrinsics.
600   auto RemoveUses = [&](StringRef Name) {
601     if (auto *DbgVal = M.getFunction(Name)) {
602       while (!DbgVal->use_empty())
603         cast<Instruction>(DbgVal->user_back())->eraseFromParent();
604       DbgVal->eraseFromParent();
605       Changed = true;
606     }
607   };
608   RemoveUses("llvm.dbg.declare");
609   RemoveUses("llvm.dbg.value");
610 
611   // Delete non-CU debug info named metadata nodes.
612   for (auto NMI = M.named_metadata_begin(), NME = M.named_metadata_end();
613        NMI != NME;) {
614     NamedMDNode *NMD = &*NMI;
615     ++NMI;
616     // Specifically keep dbg.cu around.
617     if (NMD->getName() == "llvm.dbg.cu")
618       continue;
619   }
620 
621   // Drop all dbg attachments from global variables.
622   for (auto &GV : M.globals())
623     GV.eraseMetadata(LLVMContext::MD_dbg);
624 
625   DebugTypeInfoRemoval Mapper(M.getContext());
626   auto remap = [&](MDNode *Node) -> MDNode * {
627     if (!Node)
628       return nullptr;
629     Mapper.traverseAndRemap(Node);
630     auto *NewNode = Mapper.mapNode(Node);
631     Changed |= Node != NewNode;
632     Node = NewNode;
633     return NewNode;
634   };
635 
636   // Rewrite the DebugLocs to be equivalent to what
637   // -gline-tables-only would have created.
638   for (auto &F : M) {
639     if (auto *SP = F.getSubprogram()) {
640       Mapper.traverseAndRemap(SP);
641       auto *NewSP = cast<DISubprogram>(Mapper.mapNode(SP));
642       Changed |= SP != NewSP;
643       F.setSubprogram(NewSP);
644     }
645     for (auto &BB : F) {
646       for (auto &I : BB) {
647         auto remapDebugLoc = [&](DebugLoc DL) -> DebugLoc {
648           auto *Scope = DL.getScope();
649           MDNode *InlinedAt = DL.getInlinedAt();
650           Scope = remap(Scope);
651           InlinedAt = remap(InlinedAt);
652           return DebugLoc::get(DL.getLine(), DL.getCol(), Scope, InlinedAt);
653         };
654 
655         if (I.getDebugLoc() != DebugLoc())
656           I.setDebugLoc(remapDebugLoc(I.getDebugLoc()));
657 
658         // Remap DILocations in untyped MDNodes (e.g., llvm.loop).
659         SmallVector<std::pair<unsigned, MDNode *>, 2> MDs;
660         I.getAllMetadata(MDs);
661         for (auto Attachment : MDs)
662           if (auto *T = dyn_cast_or_null<MDTuple>(Attachment.second))
663             for (unsigned N = 0; N < T->getNumOperands(); ++N)
664               if (auto *Loc = dyn_cast_or_null<DILocation>(T->getOperand(N)))
665                 if (Loc != DebugLoc())
666                   T->replaceOperandWith(N, remapDebugLoc(Loc));
667       }
668     }
669   }
670 
671   // Create a new llvm.dbg.cu, which is equivalent to the one
672   // -gline-tables-only would have created.
673   for (auto &NMD : M.getNamedMDList()) {
674     SmallVector<MDNode *, 8> Ops;
675     for (MDNode *Op : NMD.operands())
676       Ops.push_back(remap(Op));
677 
678     if (!Changed)
679       continue;
680 
681     NMD.clearOperands();
682     for (auto *Op : Ops)
683       if (Op)
684         NMD.addOperand(Op);
685   }
686   return Changed;
687 }
688 
689 unsigned llvm::getDebugMetadataVersionFromModule(const Module &M) {
690   if (auto *Val = mdconst::dyn_extract_or_null<ConstantInt>(
691           M.getModuleFlag("Debug Info Version")))
692     return Val->getZExtValue();
693   return 0;
694 }
695 
696 void Instruction::applyMergedLocation(const DILocation *LocA,
697                                       const DILocation *LocB) {
698   setDebugLoc(DILocation::getMergedLocation(LocA, LocB,
699                                             DILocation::WithGeneratedLocation));
700 }
701 
702 //===----------------------------------------------------------------------===//
703 // LLVM C API implementations.
704 //===----------------------------------------------------------------------===//
705 
706 static unsigned map_from_llvmDWARFsourcelanguage(LLVMDWARFSourceLanguage lang) {
707   switch (lang) {
708 #define HANDLE_DW_LANG(ID, NAME, VERSION, VENDOR) \
709 case LLVMDWARFSourceLanguage##NAME: return ID;
710 #include "llvm/BinaryFormat/Dwarf.def"
711 #undef HANDLE_DW_LANG
712   }
713   llvm_unreachable("Unhandled Tag");
714 }
715 
716 template <typename DIT> DIT *unwrapDI(LLVMMetadataRef Ref) {
717   return (DIT *)(Ref ? unwrap<MDNode>(Ref) : nullptr);
718 }
719 
720 static DINode::DIFlags map_from_llvmDIFlags(LLVMDIFlags Flags) {
721   return static_cast<DINode::DIFlags>(Flags);
722 }
723 
724 static LLVMDIFlags map_to_llvmDIFlags(DINode::DIFlags Flags) {
725   return static_cast<LLVMDIFlags>(Flags);
726 }
727 
728 unsigned LLVMDebugMetadataVersion() {
729   return DEBUG_METADATA_VERSION;
730 }
731 
732 LLVMDIBuilderRef LLVMCreateDIBuilderDisallowUnresolved(LLVMModuleRef M) {
733   return wrap(new DIBuilder(*unwrap(M), false));
734 }
735 
736 LLVMDIBuilderRef LLVMCreateDIBuilder(LLVMModuleRef M) {
737   return wrap(new DIBuilder(*unwrap(M)));
738 }
739 
740 unsigned LLVMGetModuleDebugMetadataVersion(LLVMModuleRef M) {
741   return getDebugMetadataVersionFromModule(*unwrap(M));
742 }
743 
744 LLVMBool LLVMStripModuleDebugInfo(LLVMModuleRef M) {
745   return StripDebugInfo(*unwrap(M));
746 }
747 
748 void LLVMDisposeDIBuilder(LLVMDIBuilderRef Builder) {
749   delete unwrap(Builder);
750 }
751 
752 void LLVMDIBuilderFinalize(LLVMDIBuilderRef Builder) {
753   unwrap(Builder)->finalize();
754 }
755 
756 LLVMMetadataRef LLVMDIBuilderCreateCompileUnit(
757     LLVMDIBuilderRef Builder, LLVMDWARFSourceLanguage Lang,
758     LLVMMetadataRef FileRef, const char *Producer, size_t ProducerLen,
759     LLVMBool isOptimized, const char *Flags, size_t FlagsLen,
760     unsigned RuntimeVer, const char *SplitName, size_t SplitNameLen,
761     LLVMDWARFEmissionKind Kind, unsigned DWOId, LLVMBool SplitDebugInlining,
762     LLVMBool DebugInfoForProfiling) {
763   auto File = unwrapDI<DIFile>(FileRef);
764 
765   return wrap(unwrap(Builder)->createCompileUnit(
766                  map_from_llvmDWARFsourcelanguage(Lang), File,
767                  StringRef(Producer, ProducerLen), isOptimized,
768                  StringRef(Flags, FlagsLen), RuntimeVer,
769                  StringRef(SplitName, SplitNameLen),
770                  static_cast<DICompileUnit::DebugEmissionKind>(Kind), DWOId,
771                  SplitDebugInlining, DebugInfoForProfiling));
772 }
773 
774 LLVMMetadataRef
775 LLVMDIBuilderCreateFile(LLVMDIBuilderRef Builder, const char *Filename,
776                         size_t FilenameLen, const char *Directory,
777                         size_t DirectoryLen) {
778   return wrap(unwrap(Builder)->createFile(StringRef(Filename, FilenameLen),
779                                           StringRef(Directory, DirectoryLen)));
780 }
781 
782 LLVMMetadataRef
783 LLVMDIBuilderCreateModule(LLVMDIBuilderRef Builder, LLVMMetadataRef ParentScope,
784                           const char *Name, size_t NameLen,
785                           const char *ConfigMacros, size_t ConfigMacrosLen,
786                           const char *IncludePath, size_t IncludePathLen,
787                           const char *ISysRoot, size_t ISysRootLen) {
788   return wrap(unwrap(Builder)->createModule(
789       unwrapDI<DIScope>(ParentScope), StringRef(Name, NameLen),
790       StringRef(ConfigMacros, ConfigMacrosLen),
791       StringRef(IncludePath, IncludePathLen),
792       StringRef(ISysRoot, ISysRootLen)));
793 }
794 
795 LLVMMetadataRef LLVMDIBuilderCreateNameSpace(LLVMDIBuilderRef Builder,
796                                              LLVMMetadataRef ParentScope,
797                                              const char *Name, size_t NameLen,
798                                              LLVMBool ExportSymbols) {
799   return wrap(unwrap(Builder)->createNameSpace(
800       unwrapDI<DIScope>(ParentScope), StringRef(Name, NameLen), ExportSymbols));
801 }
802 
803 LLVMMetadataRef LLVMDIBuilderCreateFunction(
804     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
805     size_t NameLen, const char *LinkageName, size_t LinkageNameLen,
806     LLVMMetadataRef File, unsigned LineNo, LLVMMetadataRef Ty,
807     LLVMBool IsLocalToUnit, LLVMBool IsDefinition,
808     unsigned ScopeLine, LLVMDIFlags Flags, LLVMBool IsOptimized) {
809   return wrap(unwrap(Builder)->createFunction(
810       unwrapDI<DIScope>(Scope), {Name, NameLen}, {LinkageName, LinkageNameLen},
811       unwrapDI<DIFile>(File), LineNo, unwrapDI<DISubroutineType>(Ty),
812       IsLocalToUnit, IsDefinition, ScopeLine, map_from_llvmDIFlags(Flags),
813       IsOptimized, nullptr, nullptr, nullptr));
814 }
815 
816 
817 LLVMMetadataRef LLVMDIBuilderCreateLexicalBlock(
818     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope,
819     LLVMMetadataRef File, unsigned Line, unsigned Col) {
820   return wrap(unwrap(Builder)->createLexicalBlock(unwrapDI<DIScope>(Scope),
821                                                   unwrapDI<DIFile>(File),
822                                                   Line, Col));
823 }
824 
825 LLVMMetadataRef
826 LLVMDIBuilderCreateLexicalBlockFile(LLVMDIBuilderRef Builder,
827                                     LLVMMetadataRef Scope,
828                                     LLVMMetadataRef File,
829                                     unsigned Discriminator) {
830   return wrap(unwrap(Builder)->createLexicalBlockFile(unwrapDI<DIScope>(Scope),
831                                                       unwrapDI<DIFile>(File),
832                                                       Discriminator));
833 }
834 
835 LLVMMetadataRef
836 LLVMDIBuilderCreateImportedModuleFromNamespace(LLVMDIBuilderRef Builder,
837                                                LLVMMetadataRef Scope,
838                                                LLVMMetadataRef NS,
839                                                LLVMMetadataRef File,
840                                                unsigned Line) {
841   return wrap(unwrap(Builder)->createImportedModule(unwrapDI<DIScope>(Scope),
842                                                     unwrapDI<DINamespace>(NS),
843                                                     unwrapDI<DIFile>(File),
844                                                     Line));
845 }
846 
847 LLVMMetadataRef
848 LLVMDIBuilderCreateImportedModuleFromAlias(LLVMDIBuilderRef Builder,
849                                            LLVMMetadataRef Scope,
850                                            LLVMMetadataRef ImportedEntity,
851                                            LLVMMetadataRef File,
852                                            unsigned Line) {
853   return wrap(unwrap(Builder)->createImportedModule(
854                   unwrapDI<DIScope>(Scope),
855                   unwrapDI<DIImportedEntity>(ImportedEntity),
856                   unwrapDI<DIFile>(File), Line));
857 }
858 
859 LLVMMetadataRef
860 LLVMDIBuilderCreateImportedModuleFromModule(LLVMDIBuilderRef Builder,
861                                             LLVMMetadataRef Scope,
862                                             LLVMMetadataRef M,
863                                             LLVMMetadataRef File,
864                                             unsigned Line) {
865   return wrap(unwrap(Builder)->createImportedModule(unwrapDI<DIScope>(Scope),
866                                                     unwrapDI<DIModule>(M),
867                                                     unwrapDI<DIFile>(File),
868                                                     Line));
869 }
870 
871 LLVMMetadataRef
872 LLVMDIBuilderCreateImportedDeclaration(LLVMDIBuilderRef Builder,
873                                        LLVMMetadataRef Scope,
874                                        LLVMMetadataRef Decl,
875                                        LLVMMetadataRef File,
876                                        unsigned Line,
877                                        const char *Name, size_t NameLen) {
878   return wrap(unwrap(Builder)->createImportedDeclaration(
879                   unwrapDI<DIScope>(Scope),
880                   unwrapDI<DINode>(Decl),
881                   unwrapDI<DIFile>(File), Line, {Name, NameLen}));
882 }
883 
884 LLVMMetadataRef
885 LLVMDIBuilderCreateDebugLocation(LLVMContextRef Ctx, unsigned Line,
886                                  unsigned Column, LLVMMetadataRef Scope,
887                                  LLVMMetadataRef InlinedAt) {
888   return wrap(DILocation::get(*unwrap(Ctx), Line, Column, unwrap(Scope),
889                               unwrap(InlinedAt)));
890 }
891 
892 unsigned LLVMDILocationGetLine(LLVMMetadataRef Location) {
893   return unwrapDI<DILocation>(Location)->getLine();
894 }
895 
896 unsigned LLVMDILocationGetColumn(LLVMMetadataRef Location) {
897   return unwrapDI<DILocation>(Location)->getColumn();
898 }
899 
900 LLVMMetadataRef LLVMDILocationGetScope(LLVMMetadataRef Location) {
901   return wrap(unwrapDI<DILocation>(Location)->getScope());
902 }
903 
904 LLVMMetadataRef LLVMDIBuilderCreateEnumerationType(
905   LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
906   size_t NameLen, LLVMMetadataRef File, unsigned LineNumber,
907   uint64_t SizeInBits, uint32_t AlignInBits, LLVMMetadataRef *Elements,
908   unsigned NumElements, LLVMMetadataRef ClassTy) {
909 auto Elts = unwrap(Builder)->getOrCreateArray({unwrap(Elements),
910                                                NumElements});
911 return wrap(unwrap(Builder)->createEnumerationType(
912     unwrapDI<DIScope>(Scope), {Name, NameLen}, unwrapDI<DIFile>(File),
913     LineNumber, SizeInBits, AlignInBits, Elts, unwrapDI<DIType>(ClassTy)));
914 }
915 
916 LLVMMetadataRef LLVMDIBuilderCreateUnionType(
917   LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
918   size_t NameLen, LLVMMetadataRef File, unsigned LineNumber,
919   uint64_t SizeInBits, uint32_t AlignInBits, LLVMDIFlags Flags,
920   LLVMMetadataRef *Elements, unsigned NumElements, unsigned RunTimeLang,
921   const char *UniqueId, size_t UniqueIdLen) {
922   auto Elts = unwrap(Builder)->getOrCreateArray({unwrap(Elements),
923                                                  NumElements});
924   return wrap(unwrap(Builder)->createUnionType(
925      unwrapDI<DIScope>(Scope), {Name, NameLen}, unwrapDI<DIFile>(File),
926      LineNumber, SizeInBits, AlignInBits, map_from_llvmDIFlags(Flags),
927      Elts, RunTimeLang, {UniqueId, UniqueIdLen}));
928 }
929 
930 
931 LLVMMetadataRef
932 LLVMDIBuilderCreateArrayType(LLVMDIBuilderRef Builder, uint64_t Size,
933                              uint32_t AlignInBits, LLVMMetadataRef Ty,
934                              LLVMMetadataRef *Subscripts,
935                              unsigned NumSubscripts) {
936   auto Subs = unwrap(Builder)->getOrCreateArray({unwrap(Subscripts),
937                                                  NumSubscripts});
938   return wrap(unwrap(Builder)->createArrayType(Size, AlignInBits,
939                                                unwrapDI<DIType>(Ty), Subs));
940 }
941 
942 LLVMMetadataRef
943 LLVMDIBuilderCreateVectorType(LLVMDIBuilderRef Builder, uint64_t Size,
944                               uint32_t AlignInBits, LLVMMetadataRef Ty,
945                               LLVMMetadataRef *Subscripts,
946                               unsigned NumSubscripts) {
947   auto Subs = unwrap(Builder)->getOrCreateArray({unwrap(Subscripts),
948                                                  NumSubscripts});
949   return wrap(unwrap(Builder)->createVectorType(Size, AlignInBits,
950                                                 unwrapDI<DIType>(Ty), Subs));
951 }
952 
953 LLVMMetadataRef
954 LLVMDIBuilderCreateBasicType(LLVMDIBuilderRef Builder, const char *Name,
955                              size_t NameLen, uint64_t SizeInBits,
956                              LLVMDWARFTypeEncoding Encoding) {
957   return wrap(unwrap(Builder)->createBasicType({Name, NameLen},
958                                                SizeInBits, Encoding));
959 }
960 
961 LLVMMetadataRef LLVMDIBuilderCreatePointerType(
962     LLVMDIBuilderRef Builder, LLVMMetadataRef PointeeTy,
963     uint64_t SizeInBits, uint32_t AlignInBits, unsigned AddressSpace,
964     const char *Name, size_t NameLen) {
965   return wrap(unwrap(Builder)->createPointerType(unwrapDI<DIType>(PointeeTy),
966                                          SizeInBits, AlignInBits,
967                                          AddressSpace, {Name, NameLen}));
968 }
969 
970 LLVMMetadataRef LLVMDIBuilderCreateStructType(
971     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
972     size_t NameLen, LLVMMetadataRef File, unsigned LineNumber,
973     uint64_t SizeInBits, uint32_t AlignInBits, LLVMDIFlags Flags,
974     LLVMMetadataRef DerivedFrom, LLVMMetadataRef *Elements,
975     unsigned NumElements, unsigned RunTimeLang, LLVMMetadataRef VTableHolder,
976     const char *UniqueId, size_t UniqueIdLen) {
977   auto Elts = unwrap(Builder)->getOrCreateArray({unwrap(Elements),
978                                                  NumElements});
979   return wrap(unwrap(Builder)->createStructType(
980       unwrapDI<DIScope>(Scope), {Name, NameLen}, unwrapDI<DIFile>(File),
981       LineNumber, SizeInBits, AlignInBits, map_from_llvmDIFlags(Flags),
982       unwrapDI<DIType>(DerivedFrom), Elts, RunTimeLang,
983       unwrapDI<DIType>(VTableHolder), {UniqueId, UniqueIdLen}));
984 }
985 
986 LLVMMetadataRef LLVMDIBuilderCreateMemberType(
987     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
988     size_t NameLen, LLVMMetadataRef File, unsigned LineNo, uint64_t SizeInBits,
989     uint32_t AlignInBits, uint64_t OffsetInBits, LLVMDIFlags Flags,
990     LLVMMetadataRef Ty) {
991   return wrap(unwrap(Builder)->createMemberType(unwrapDI<DIScope>(Scope),
992       {Name, NameLen}, unwrapDI<DIFile>(File), LineNo, SizeInBits, AlignInBits,
993       OffsetInBits, map_from_llvmDIFlags(Flags), unwrapDI<DIType>(Ty)));
994 }
995 
996 LLVMMetadataRef
997 LLVMDIBuilderCreateUnspecifiedType(LLVMDIBuilderRef Builder, const char *Name,
998                                    size_t NameLen) {
999   return wrap(unwrap(Builder)->createUnspecifiedType({Name, NameLen}));
1000 }
1001 
1002 LLVMMetadataRef
1003 LLVMDIBuilderCreateStaticMemberType(
1004     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1005     size_t NameLen, LLVMMetadataRef File, unsigned LineNumber,
1006     LLVMMetadataRef Type, LLVMDIFlags Flags, LLVMValueRef ConstantVal,
1007     uint32_t AlignInBits) {
1008   return wrap(unwrap(Builder)->createStaticMemberType(
1009                   unwrapDI<DIScope>(Scope), {Name, NameLen},
1010                   unwrapDI<DIFile>(File), LineNumber, unwrapDI<DIType>(Type),
1011                   map_from_llvmDIFlags(Flags), unwrap<Constant>(ConstantVal),
1012                   AlignInBits));
1013 }
1014 
1015 LLVMMetadataRef
1016 LLVMDIBuilderCreateObjectPointerType(LLVMDIBuilderRef Builder,
1017                                      LLVMMetadataRef Type) {
1018   return wrap(unwrap(Builder)->createObjectPointerType(unwrapDI<DIType>(Type)));
1019 }
1020 
1021 LLVMMetadataRef
1022 LLVMDIBuilderCreateForwardDecl(
1023     LLVMDIBuilderRef Builder, unsigned Tag, const char *Name,
1024     size_t NameLen, LLVMMetadataRef Scope, LLVMMetadataRef File, unsigned Line,
1025     unsigned RuntimeLang, uint64_t SizeInBits, uint32_t AlignInBits,
1026     const char *UniqueIdentifier, size_t UniqueIdentifierLen) {
1027   return wrap(unwrap(Builder)->createForwardDecl(
1028                   Tag, {Name, NameLen}, unwrapDI<DIScope>(Scope),
1029                   unwrapDI<DIFile>(File), Line, RuntimeLang, SizeInBits,
1030                   AlignInBits, {UniqueIdentifier, UniqueIdentifierLen}));
1031 }
1032 
1033 LLVMMetadataRef
1034 LLVMDIBuilderCreateReplaceableCompositeType(
1035     LLVMDIBuilderRef Builder, unsigned Tag, const char *Name,
1036     size_t NameLen, LLVMMetadataRef Scope, LLVMMetadataRef File, unsigned Line,
1037     unsigned RuntimeLang, uint64_t SizeInBits, uint32_t AlignInBits,
1038     LLVMDIFlags Flags, const char *UniqueIdentifier,
1039     size_t UniqueIdentifierLen) {
1040   return wrap(unwrap(Builder)->createReplaceableCompositeType(
1041                   Tag, {Name, NameLen}, unwrapDI<DIScope>(Scope),
1042                   unwrapDI<DIFile>(File), Line, RuntimeLang, SizeInBits,
1043                   AlignInBits, map_from_llvmDIFlags(Flags),
1044                   {UniqueIdentifier, UniqueIdentifierLen}));
1045 }
1046 
1047 LLVMMetadataRef
1048 LLVMDIBuilderCreateQualifiedType(LLVMDIBuilderRef Builder, unsigned Tag,
1049                                  LLVMMetadataRef Type) {
1050   return wrap(unwrap(Builder)->createQualifiedType(Tag,
1051                                                    unwrapDI<DIType>(Type)));
1052 }
1053 
1054 LLVMMetadataRef
1055 LLVMDIBuilderCreateReferenceType(LLVMDIBuilderRef Builder, unsigned Tag,
1056                                  LLVMMetadataRef Type) {
1057   return wrap(unwrap(Builder)->createReferenceType(Tag,
1058                                                    unwrapDI<DIType>(Type)));
1059 }
1060 
1061 LLVMMetadataRef
1062 LLVMDIBuilderCreateNullPtrType(LLVMDIBuilderRef Builder) {
1063   return wrap(unwrap(Builder)->createNullPtrType());
1064 }
1065 
1066 LLVMMetadataRef
1067 LLVMDIBuilderCreateMemberPointerType(LLVMDIBuilderRef Builder,
1068                                      LLVMMetadataRef PointeeType,
1069                                      LLVMMetadataRef ClassType,
1070                                      uint64_t SizeInBits,
1071                                      uint32_t AlignInBits,
1072                                      LLVMDIFlags Flags) {
1073   return wrap(unwrap(Builder)->createMemberPointerType(
1074                   unwrapDI<DIType>(PointeeType),
1075                   unwrapDI<DIType>(ClassType), AlignInBits, SizeInBits,
1076                   map_from_llvmDIFlags(Flags)));
1077 }
1078 
1079 LLVMMetadataRef
1080 LLVMDIBuilderCreateBitFieldMemberType(LLVMDIBuilderRef Builder,
1081                                       LLVMMetadataRef Scope,
1082                                       const char *Name, size_t NameLen,
1083                                       LLVMMetadataRef File, unsigned LineNumber,
1084                                       uint64_t SizeInBits,
1085                                       uint64_t OffsetInBits,
1086                                       uint64_t StorageOffsetInBits,
1087                                       LLVMDIFlags Flags, LLVMMetadataRef Type) {
1088   return wrap(unwrap(Builder)->createBitFieldMemberType(
1089                   unwrapDI<DIScope>(Scope), {Name, NameLen},
1090                   unwrapDI<DIFile>(File), LineNumber,
1091                   SizeInBits, OffsetInBits, StorageOffsetInBits,
1092                   map_from_llvmDIFlags(Flags), unwrapDI<DIType>(Type)));
1093 }
1094 
1095 LLVMMetadataRef LLVMDIBuilderCreateClassType(LLVMDIBuilderRef Builder,
1096     LLVMMetadataRef Scope, const char *Name, size_t NameLen,
1097     LLVMMetadataRef File, unsigned LineNumber, uint64_t SizeInBits,
1098     uint32_t AlignInBits, uint64_t OffsetInBits, LLVMDIFlags Flags,
1099     LLVMMetadataRef DerivedFrom,
1100     LLVMMetadataRef *Elements, unsigned NumElements,
1101     LLVMMetadataRef VTableHolder, LLVMMetadataRef TemplateParamsNode,
1102     const char *UniqueIdentifier, size_t UniqueIdentifierLen) {
1103   auto Elts = unwrap(Builder)->getOrCreateArray({unwrap(Elements),
1104                                                  NumElements});
1105   return wrap(unwrap(Builder)->createClassType(
1106                   unwrapDI<DIScope>(Scope), {Name, NameLen},
1107                   unwrapDI<DIFile>(File), LineNumber,
1108                   SizeInBits, AlignInBits, OffsetInBits,
1109                   map_from_llvmDIFlags(Flags), unwrapDI<DIType>(DerivedFrom),
1110                   Elts, unwrapDI<DIType>(VTableHolder),
1111                   unwrapDI<MDNode>(TemplateParamsNode),
1112                   {UniqueIdentifier, UniqueIdentifierLen}));
1113 }
1114 
1115 LLVMMetadataRef
1116 LLVMDIBuilderCreateArtificialType(LLVMDIBuilderRef Builder,
1117                                   LLVMMetadataRef Type) {
1118   return wrap(unwrap(Builder)->createArtificialType(unwrapDI<DIType>(Type)));
1119 }
1120 
1121 const char *LLVMDITypeGetName(LLVMMetadataRef DType, size_t *Length) {
1122   StringRef Str = unwrap<DIType>(DType)->getName();
1123   *Length = Str.size();
1124   return Str.data();
1125 }
1126 
1127 uint64_t LLVMDITypeGetSizeInBits(LLVMMetadataRef DType) {
1128   return unwrapDI<DIType>(DType)->getSizeInBits();
1129 }
1130 
1131 uint64_t LLVMDITypeGetOffsetInBits(LLVMMetadataRef DType) {
1132   return unwrapDI<DIType>(DType)->getOffsetInBits();
1133 }
1134 
1135 uint32_t LLVMDITypeGetAlignInBits(LLVMMetadataRef DType) {
1136   return unwrapDI<DIType>(DType)->getAlignInBits();
1137 }
1138 
1139 unsigned LLVMDITypeGetLine(LLVMMetadataRef DType) {
1140   return unwrapDI<DIType>(DType)->getLine();
1141 }
1142 
1143 LLVMDIFlags LLVMDITypeGetFlags(LLVMMetadataRef DType) {
1144   return map_to_llvmDIFlags(unwrapDI<DIType>(DType)->getFlags());
1145 }
1146 
1147 LLVMMetadataRef LLVMDIBuilderGetOrCreateTypeArray(LLVMDIBuilderRef Builder,
1148                                                   LLVMMetadataRef *Types,
1149                                                   size_t Length) {
1150   return wrap(
1151       unwrap(Builder)->getOrCreateTypeArray({unwrap(Types), Length}).get());
1152 }
1153 
1154 LLVMMetadataRef
1155 LLVMDIBuilderCreateSubroutineType(LLVMDIBuilderRef Builder,
1156                                   LLVMMetadataRef File,
1157                                   LLVMMetadataRef *ParameterTypes,
1158                                   unsigned NumParameterTypes,
1159                                   LLVMDIFlags Flags) {
1160   auto Elts = unwrap(Builder)->getOrCreateTypeArray({unwrap(ParameterTypes),
1161                                                      NumParameterTypes});
1162   return wrap(unwrap(Builder)->createSubroutineType(
1163     Elts, map_from_llvmDIFlags(Flags)));
1164 }
1165 
1166 LLVMMetadataRef LLVMDIBuilderCreateExpression(LLVMDIBuilderRef Builder,
1167                                               int64_t *Addr, size_t Length) {
1168   return wrap(unwrap(Builder)->createExpression(ArrayRef<int64_t>(Addr,
1169                                                                   Length)));
1170 }
1171 
1172 LLVMMetadataRef
1173 LLVMDIBuilderCreateConstantValueExpression(LLVMDIBuilderRef Builder,
1174                                            int64_t Value) {
1175   return wrap(unwrap(Builder)->createConstantValueExpression(Value));
1176 }
1177 
1178 LLVMMetadataRef
1179 LLVMDIBuilderCreateGlobalVariableExpression(LLVMDIBuilderRef Builder,
1180                                             LLVMMetadataRef Scope,
1181                                             const char *Name, size_t NameLen,
1182                                             const char *Linkage, size_t LinkLen,
1183                                             LLVMMetadataRef File,
1184                                             unsigned LineNo,
1185                                             LLVMMetadataRef Ty,
1186                                             LLVMBool LocalToUnit,
1187                                             LLVMMetadataRef Expr,
1188                                             LLVMMetadataRef Decl,
1189                                             uint32_t AlignInBits) {
1190   return wrap(unwrap(Builder)->createGlobalVariableExpression(
1191                   unwrapDI<DIScope>(Scope), {Name, NameLen}, {Linkage, LinkLen},
1192                   unwrapDI<DIFile>(File), LineNo, unwrapDI<DIType>(Ty),
1193                   LocalToUnit, unwrap<DIExpression>(Expr),
1194                   unwrapDI<MDNode>(Decl), AlignInBits));
1195 }
1196 
1197 LLVMMetadataRef LLVMTemporaryMDNode(LLVMContextRef Ctx, LLVMMetadataRef *Data,
1198                                     size_t Count) {
1199   return wrap(
1200       MDTuple::getTemporary(*unwrap(Ctx), {unwrap(Data), Count}).release());
1201 }
1202 
1203 void LLVMDisposeTemporaryMDNode(LLVMMetadataRef TempNode) {
1204   MDNode::deleteTemporary(unwrapDI<MDNode>(TempNode));
1205 }
1206 
1207 void LLVMMetadataReplaceAllUsesWith(LLVMMetadataRef TargetMetadata,
1208                                     LLVMMetadataRef Replacement) {
1209   auto *Node = unwrapDI<MDNode>(TargetMetadata);
1210   Node->replaceAllUsesWith(unwrap<Metadata>(Replacement));
1211   MDNode::deleteTemporary(Node);
1212 }
1213 
1214 LLVMMetadataRef
1215 LLVMDIBuilderCreateTempGlobalVariableFwdDecl(LLVMDIBuilderRef Builder,
1216                                              LLVMMetadataRef Scope,
1217                                              const char *Name, size_t NameLen,
1218                                              const char *Linkage, size_t LnkLen,
1219                                              LLVMMetadataRef File,
1220                                              unsigned LineNo,
1221                                              LLVMMetadataRef Ty,
1222                                              LLVMBool LocalToUnit,
1223                                              LLVMMetadataRef Decl,
1224                                              uint32_t AlignInBits) {
1225   return wrap(unwrap(Builder)->createTempGlobalVariableFwdDecl(
1226                   unwrapDI<DIScope>(Scope), {Name, NameLen}, {Linkage, LnkLen},
1227                   unwrapDI<DIFile>(File), LineNo, unwrapDI<DIType>(Ty),
1228                   LocalToUnit, unwrapDI<MDNode>(Decl), AlignInBits));
1229 }
1230 
1231 LLVMValueRef LLVMDIBuilderInsertDeclareBefore(
1232   LLVMDIBuilderRef Builder, LLVMValueRef Storage, LLVMMetadataRef VarInfo,
1233   LLVMMetadataRef Expr, LLVMMetadataRef DL, LLVMValueRef Instr) {
1234   return wrap(unwrap(Builder)->insertDeclare(
1235                   unwrap(Storage), unwrap<DILocalVariable>(VarInfo),
1236                   unwrap<DIExpression>(Expr), unwrap<DILocation>(DL),
1237                   unwrap<Instruction>(Instr)));
1238 }
1239 
1240 LLVMValueRef LLVMDIBuilderInsertDeclareAtEnd(
1241     LLVMDIBuilderRef Builder, LLVMValueRef Storage, LLVMMetadataRef VarInfo,
1242     LLVMMetadataRef Expr, LLVMMetadataRef DL, LLVMBasicBlockRef Block) {
1243   return wrap(unwrap(Builder)->insertDeclare(
1244                   unwrap(Storage), unwrap<DILocalVariable>(VarInfo),
1245                   unwrap<DIExpression>(Expr), unwrap<DILocation>(DL),
1246                   unwrap(Block)));
1247 }
1248 
1249 LLVMValueRef LLVMDIBuilderInsertDbgValueBefore(LLVMDIBuilderRef Builder,
1250                                                LLVMValueRef Val,
1251                                                LLVMMetadataRef VarInfo,
1252                                                LLVMMetadataRef Expr,
1253                                                LLVMMetadataRef DebugLoc,
1254                                                LLVMValueRef Instr) {
1255   return wrap(unwrap(Builder)->insertDbgValueIntrinsic(
1256                   unwrap(Val), unwrap<DILocalVariable>(VarInfo),
1257                   unwrap<DIExpression>(Expr), unwrap<DILocation>(DebugLoc),
1258                   unwrap<Instruction>(Instr)));
1259 }
1260 
1261 LLVMValueRef LLVMDIBuilderInsertDbgValueAtEnd(LLVMDIBuilderRef Builder,
1262                                               LLVMValueRef Val,
1263                                               LLVMMetadataRef VarInfo,
1264                                               LLVMMetadataRef Expr,
1265                                               LLVMMetadataRef DebugLoc,
1266                                               LLVMBasicBlockRef Block) {
1267   return wrap(unwrap(Builder)->insertDbgValueIntrinsic(
1268                   unwrap(Val), unwrap<DILocalVariable>(VarInfo),
1269                   unwrap<DIExpression>(Expr), unwrap<DILocation>(DebugLoc),
1270                   unwrap(Block)));
1271 }
1272 
1273 LLVMMetadataRef LLVMDIBuilderCreateAutoVariable(
1274     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1275     size_t NameLen, LLVMMetadataRef File, unsigned LineNo, LLVMMetadataRef Ty,
1276     LLVMBool AlwaysPreserve, LLVMDIFlags Flags, uint32_t AlignInBits) {
1277   return wrap(unwrap(Builder)->createAutoVariable(
1278                   unwrap<DIScope>(Scope), {Name, NameLen}, unwrap<DIFile>(File),
1279                   LineNo, unwrap<DIType>(Ty), AlwaysPreserve,
1280                   map_from_llvmDIFlags(Flags), AlignInBits));
1281 }
1282 
1283 LLVMMetadataRef LLVMDIBuilderCreateParameterVariable(
1284     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1285     size_t NameLen, unsigned ArgNo, LLVMMetadataRef File, unsigned LineNo,
1286     LLVMMetadataRef Ty, LLVMBool AlwaysPreserve, LLVMDIFlags Flags) {
1287   return wrap(unwrap(Builder)->createParameterVariable(
1288                   unwrap<DIScope>(Scope), Name, ArgNo, unwrap<DIFile>(File),
1289                   LineNo, unwrap<DIType>(Ty), AlwaysPreserve,
1290                   map_from_llvmDIFlags(Flags)));
1291 }
1292 
1293 LLVMMetadataRef LLVMDIBuilderGetOrCreateSubrange(LLVMDIBuilderRef Builder,
1294                                                  int64_t Lo, int64_t Count) {
1295   return wrap(unwrap(Builder)->getOrCreateSubrange(Lo, Count));
1296 }
1297 
1298 LLVMMetadataRef LLVMDIBuilderGetOrCreateArray(LLVMDIBuilderRef Builder,
1299                                               LLVMMetadataRef *Data,
1300                                               size_t Length) {
1301   Metadata **DataValue = unwrap(Data);
1302   return wrap(unwrap(Builder)->getOrCreateArray({DataValue, Length}).get());
1303 }
1304 
1305 LLVMMetadataRef LLVMGetSubprogram(LLVMValueRef Func) {
1306   return wrap(unwrap<Function>(Func)->getSubprogram());
1307 }
1308 
1309 void LLVMSetSubprogram(LLVMValueRef Func, LLVMMetadataRef SP) {
1310   unwrap<Function>(Func)->setSubprogram(unwrap<DISubprogram>(SP));
1311 }
1312