1 //===- DebugInfo.cpp - Debug Information Helper Classes -------------------===//
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 // This file implements the helper classes used to build and interpret debug
10 // information in LLVM IR form.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm-c/DebugInfo.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/SmallPtrSet.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/ADT/StringRef.h"
22 #include "llvm/IR/BasicBlock.h"
23 #include "llvm/IR/Constants.h"
24 #include "llvm/IR/DebugInfoMetadata.h"
25 #include "llvm/IR/DebugLoc.h"
26 #include "llvm/IR/DebugInfo.h"
27 #include "llvm/IR/DIBuilder.h"
28 #include "llvm/IR/Function.h"
29 #include "llvm/IR/GVMaterializer.h"
30 #include "llvm/IR/Instruction.h"
31 #include "llvm/IR/IntrinsicInst.h"
32 #include "llvm/IR/LLVMContext.h"
33 #include "llvm/IR/Metadata.h"
34 #include "llvm/IR/Module.h"
35 #include "llvm/Support/Casting.h"
36 #include <algorithm>
37 #include <cassert>
38 #include <utility>
39 
40 using namespace llvm;
41 using namespace llvm::dwarf;
42 
43 DISubprogram *llvm::getDISubprogram(const MDNode *Scope) {
44   if (auto *LocalScope = dyn_cast_or_null<DILocalScope>(Scope))
45     return LocalScope->getSubprogram();
46   return nullptr;
47 }
48 
49 //===----------------------------------------------------------------------===//
50 // DebugInfoFinder implementations.
51 //===----------------------------------------------------------------------===//
52 
53 void DebugInfoFinder::reset() {
54   CUs.clear();
55   SPs.clear();
56   GVs.clear();
57   TYs.clear();
58   Scopes.clear();
59   NodesSeen.clear();
60 }
61 
62 void DebugInfoFinder::processModule(const Module &M) {
63   for (auto *CU : M.debug_compile_units())
64     processCompileUnit(CU);
65   for (auto &F : M.functions()) {
66     if (auto *SP = cast_or_null<DISubprogram>(F.getSubprogram()))
67       processSubprogram(SP);
68     // There could be subprograms from inlined functions referenced from
69     // instructions only. Walk the function to find them.
70     for (const BasicBlock &BB : F)
71       for (const Instruction &I : BB)
72         processInstruction(M, I);
73   }
74 }
75 
76 void DebugInfoFinder::processCompileUnit(DICompileUnit *CU) {
77   if (!addCompileUnit(CU))
78     return;
79   for (auto DIG : CU->getGlobalVariables()) {
80     if (!addGlobalVariable(DIG))
81       continue;
82     auto *GV = DIG->getVariable();
83     processScope(GV->getScope());
84     processType(GV->getType());
85   }
86   for (auto *ET : CU->getEnumTypes())
87     processType(ET);
88   for (auto *RT : CU->getRetainedTypes())
89     if (auto *T = dyn_cast<DIType>(RT))
90       processType(T);
91     else
92       processSubprogram(cast<DISubprogram>(RT));
93   for (auto *Import : CU->getImportedEntities()) {
94     auto *Entity = Import->getEntity();
95     if (auto *T = dyn_cast<DIType>(Entity))
96       processType(T);
97     else if (auto *SP = dyn_cast<DISubprogram>(Entity))
98       processSubprogram(SP);
99     else if (auto *NS = dyn_cast<DINamespace>(Entity))
100       processScope(NS->getScope());
101     else if (auto *M = dyn_cast<DIModule>(Entity))
102       processScope(M->getScope());
103   }
104 }
105 
106 void DebugInfoFinder::processInstruction(const Module &M,
107                                          const Instruction &I) {
108   if (auto *DVI = dyn_cast<DbgVariableIntrinsic>(&I))
109     processVariable(M, *DVI);
110 
111   if (auto DbgLoc = I.getDebugLoc())
112     processLocation(M, DbgLoc.get());
113 }
114 
115 void DebugInfoFinder::processLocation(const Module &M, const DILocation *Loc) {
116   if (!Loc)
117     return;
118   processScope(Loc->getScope());
119   processLocation(M, Loc->getInlinedAt());
120 }
121 
122 void DebugInfoFinder::processType(DIType *DT) {
123   if (!addType(DT))
124     return;
125   processScope(DT->getScope());
126   if (auto *ST = dyn_cast<DISubroutineType>(DT)) {
127     for (DIType *Ref : ST->getTypeArray())
128       processType(Ref);
129     return;
130   }
131   if (auto *DCT = dyn_cast<DICompositeType>(DT)) {
132     processType(DCT->getBaseType());
133     for (Metadata *D : DCT->getElements()) {
134       if (auto *T = dyn_cast<DIType>(D))
135         processType(T);
136       else if (auto *SP = dyn_cast<DISubprogram>(D))
137         processSubprogram(SP);
138     }
139     return;
140   }
141   if (auto *DDT = dyn_cast<DIDerivedType>(DT)) {
142     processType(DDT->getBaseType());
143   }
144 }
145 
146 void DebugInfoFinder::processScope(DIScope *Scope) {
147   if (!Scope)
148     return;
149   if (auto *Ty = dyn_cast<DIType>(Scope)) {
150     processType(Ty);
151     return;
152   }
153   if (auto *CU = dyn_cast<DICompileUnit>(Scope)) {
154     addCompileUnit(CU);
155     return;
156   }
157   if (auto *SP = dyn_cast<DISubprogram>(Scope)) {
158     processSubprogram(SP);
159     return;
160   }
161   if (!addScope(Scope))
162     return;
163   if (auto *LB = dyn_cast<DILexicalBlockBase>(Scope)) {
164     processScope(LB->getScope());
165   } else if (auto *NS = dyn_cast<DINamespace>(Scope)) {
166     processScope(NS->getScope());
167   } else if (auto *M = dyn_cast<DIModule>(Scope)) {
168     processScope(M->getScope());
169   }
170 }
171 
172 void DebugInfoFinder::processSubprogram(DISubprogram *SP) {
173   if (!addSubprogram(SP))
174     return;
175   processScope(SP->getScope());
176   // Some of the users, e.g. CloneFunctionInto / CloneModule, need to set up a
177   // ValueMap containing identity mappings for all of the DICompileUnit's, not
178   // just DISubprogram's, referenced from anywhere within the Function being
179   // cloned prior to calling MapMetadata / RemapInstruction to avoid their
180   // duplication later as DICompileUnit's are also directly referenced by
181   // llvm.dbg.cu list. Thefore we need to collect DICompileUnit's here as well.
182   // Also, DICompileUnit's may reference DISubprogram's too and therefore need
183   // to be at least looked through.
184   processCompileUnit(SP->getUnit());
185   processType(SP->getType());
186   for (auto *Element : SP->getTemplateParams()) {
187     if (auto *TType = dyn_cast<DITemplateTypeParameter>(Element)) {
188       processType(TType->getType());
189     } else if (auto *TVal = dyn_cast<DITemplateValueParameter>(Element)) {
190       processType(TVal->getType());
191     }
192   }
193 }
194 
195 void DebugInfoFinder::processVariable(const Module &M,
196                                       const DbgVariableIntrinsic &DVI) {
197   auto *N = dyn_cast<MDNode>(DVI.getVariable());
198   if (!N)
199     return;
200 
201   auto *DV = dyn_cast<DILocalVariable>(N);
202   if (!DV)
203     return;
204 
205   if (!NodesSeen.insert(DV).second)
206     return;
207   processScope(DV->getScope());
208   processType(DV->getType());
209 }
210 
211 bool DebugInfoFinder::addType(DIType *DT) {
212   if (!DT)
213     return false;
214 
215   if (!NodesSeen.insert(DT).second)
216     return false;
217 
218   TYs.push_back(const_cast<DIType *>(DT));
219   return true;
220 }
221 
222 bool DebugInfoFinder::addCompileUnit(DICompileUnit *CU) {
223   if (!CU)
224     return false;
225   if (!NodesSeen.insert(CU).second)
226     return false;
227 
228   CUs.push_back(CU);
229   return true;
230 }
231 
232 bool DebugInfoFinder::addGlobalVariable(DIGlobalVariableExpression *DIG) {
233   if (!NodesSeen.insert(DIG).second)
234     return false;
235 
236   GVs.push_back(DIG);
237   return true;
238 }
239 
240 bool DebugInfoFinder::addSubprogram(DISubprogram *SP) {
241   if (!SP)
242     return false;
243 
244   if (!NodesSeen.insert(SP).second)
245     return false;
246 
247   SPs.push_back(SP);
248   return true;
249 }
250 
251 bool DebugInfoFinder::addScope(DIScope *Scope) {
252   if (!Scope)
253     return false;
254   // FIXME: Ocaml binding generates a scope with no content, we treat it
255   // as null for now.
256   if (Scope->getNumOperands() == 0)
257     return false;
258   if (!NodesSeen.insert(Scope).second)
259     return false;
260   Scopes.push_back(Scope);
261   return true;
262 }
263 
264 static MDNode *updateLoopMetadataDebugLocationsImpl(
265     MDNode *OrigLoopID,
266     function_ref<DILocation *(const DILocation &)> Updater) {
267   assert(OrigLoopID && OrigLoopID->getNumOperands() > 0 &&
268          "Loop ID needs at least one operand");
269   assert(OrigLoopID && OrigLoopID->getOperand(0).get() == OrigLoopID &&
270          "Loop ID should refer to itself");
271 
272   // Save space for the self-referential LoopID.
273   SmallVector<Metadata *, 4> MDs = {nullptr};
274 
275   for (unsigned i = 1; i < OrigLoopID->getNumOperands(); ++i) {
276     Metadata *MD = OrigLoopID->getOperand(i);
277     if (DILocation *DL = dyn_cast<DILocation>(MD)) {
278       if (DILocation *NewDL = Updater(*DL))
279         MDs.push_back(NewDL);
280     } else
281       MDs.push_back(MD);
282   }
283 
284   MDNode *NewLoopID = MDNode::getDistinct(OrigLoopID->getContext(), MDs);
285   // Insert the self-referential LoopID.
286   NewLoopID->replaceOperandWith(0, NewLoopID);
287   return NewLoopID;
288 }
289 
290 void llvm::updateLoopMetadataDebugLocations(
291     Instruction &I, function_ref<DILocation *(const DILocation &)> Updater) {
292   MDNode *OrigLoopID = I.getMetadata(LLVMContext::MD_loop);
293   if (!OrigLoopID)
294     return;
295   MDNode *NewLoopID = updateLoopMetadataDebugLocationsImpl(OrigLoopID, Updater);
296   I.setMetadata(LLVMContext::MD_loop, NewLoopID);
297 }
298 
299 static MDNode *stripDebugLocFromLoopID(MDNode *N) {
300   assert(!N->operands().empty() && "Missing self reference?");
301 
302   // if there is no debug location, we do not have to rewrite this MDNode.
303   if (std::none_of(N->op_begin() + 1, N->op_end(), [](const MDOperand &Op) {
304         return isa<DILocation>(Op.get());
305       }))
306     return N;
307 
308   // If there is only the debug location without any actual loop metadata, we
309   // can remove the metadata.
310   if (std::none_of(N->op_begin() + 1, N->op_end(), [](const MDOperand &Op) {
311         return !isa<DILocation>(Op.get());
312       }))
313     return nullptr;
314 
315   auto dropDebugLoc = [](const DILocation &) -> DILocation * {
316     return nullptr;
317   };
318   return updateLoopMetadataDebugLocationsImpl(N, dropDebugLoc);
319 }
320 
321 bool llvm::stripDebugInfo(Function &F) {
322   bool Changed = false;
323   if (F.hasMetadata(LLVMContext::MD_dbg)) {
324     Changed = true;
325     F.setSubprogram(nullptr);
326   }
327 
328   DenseMap<MDNode*, MDNode*> LoopIDsMap;
329   for (BasicBlock &BB : F) {
330     for (auto II = BB.begin(), End = BB.end(); II != End;) {
331       Instruction &I = *II++; // We may delete the instruction, increment now.
332       if (isa<DbgInfoIntrinsic>(&I)) {
333         I.eraseFromParent();
334         Changed = true;
335         continue;
336       }
337       if (I.getDebugLoc()) {
338         Changed = true;
339         I.setDebugLoc(DebugLoc());
340       }
341       if (auto *LoopID = I.getMetadata(LLVMContext::MD_loop)) {
342         auto *NewLoopID = LoopIDsMap.lookup(LoopID);
343         if (!NewLoopID)
344           NewLoopID = LoopIDsMap[LoopID] = stripDebugLocFromLoopID(LoopID);
345         if (NewLoopID != LoopID)
346           I.setMetadata(LLVMContext::MD_loop, NewLoopID);
347       }
348     }
349   }
350   return Changed;
351 }
352 
353 bool llvm::StripDebugInfo(Module &M) {
354   bool Changed = false;
355 
356   for (NamedMDNode &NMD : llvm::make_early_inc_range(M.named_metadata())) {
357     // We're stripping debug info, and without them, coverage information
358     // doesn't quite make sense.
359     if (NMD.getName().startswith("llvm.dbg.") ||
360         NMD.getName() == "llvm.gcov") {
361       NMD.eraseFromParent();
362       Changed = true;
363     }
364   }
365 
366   for (Function &F : M)
367     Changed |= stripDebugInfo(F);
368 
369   for (auto &GV : M.globals()) {
370     Changed |= GV.eraseMetadata(LLVMContext::MD_dbg);
371   }
372 
373   if (GVMaterializer *Materializer = M.getMaterializer())
374     Materializer->setStripDebugInfo();
375 
376   return Changed;
377 }
378 
379 namespace {
380 
381 /// Helper class to downgrade -g metadata to -gline-tables-only metadata.
382 class DebugTypeInfoRemoval {
383   DenseMap<Metadata *, Metadata *> Replacements;
384 
385 public:
386   /// The (void)() type.
387   MDNode *EmptySubroutineType;
388 
389 private:
390   /// Remember what linkage name we originally had before stripping. If we end
391   /// up making two subprograms identical who originally had different linkage
392   /// names, then we need to make one of them distinct, to avoid them getting
393   /// uniqued. Maps the new node to the old linkage name.
394   DenseMap<DISubprogram *, StringRef> NewToLinkageName;
395 
396   // TODO: Remember the distinct subprogram we created for a given linkage name,
397   // so that we can continue to unique whenever possible. Map <newly created
398   // node, old linkage name> to the first (possibly distinct) mdsubprogram
399   // created for that combination. This is not strictly needed for correctness,
400   // but can cut down on the number of MDNodes and let us diff cleanly with the
401   // output of -gline-tables-only.
402 
403 public:
404   DebugTypeInfoRemoval(LLVMContext &C)
405       : EmptySubroutineType(DISubroutineType::get(C, DINode::FlagZero, 0,
406                                                   MDNode::get(C, {}))) {}
407 
408   Metadata *map(Metadata *M) {
409     if (!M)
410       return nullptr;
411     auto Replacement = Replacements.find(M);
412     if (Replacement != Replacements.end())
413       return Replacement->second;
414 
415     return M;
416   }
417   MDNode *mapNode(Metadata *N) { return dyn_cast_or_null<MDNode>(map(N)); }
418 
419   /// Recursively remap N and all its referenced children. Does a DF post-order
420   /// traversal, so as to remap bottoms up.
421   void traverseAndRemap(MDNode *N) { traverse(N); }
422 
423 private:
424   // Create a new DISubprogram, to replace the one given.
425   DISubprogram *getReplacementSubprogram(DISubprogram *MDS) {
426     auto *FileAndScope = cast_or_null<DIFile>(map(MDS->getFile()));
427     StringRef LinkageName = MDS->getName().empty() ? MDS->getLinkageName() : "";
428     DISubprogram *Declaration = nullptr;
429     auto *Type = cast_or_null<DISubroutineType>(map(MDS->getType()));
430     DIType *ContainingType =
431         cast_or_null<DIType>(map(MDS->getContainingType()));
432     auto *Unit = cast_or_null<DICompileUnit>(map(MDS->getUnit()));
433     auto Variables = nullptr;
434     auto TemplateParams = nullptr;
435 
436     // Make a distinct DISubprogram, for situations that warrent it.
437     auto distinctMDSubprogram = [&]() {
438       return DISubprogram::getDistinct(
439           MDS->getContext(), FileAndScope, MDS->getName(), LinkageName,
440           FileAndScope, MDS->getLine(), Type, MDS->getScopeLine(),
441           ContainingType, MDS->getVirtualIndex(), MDS->getThisAdjustment(),
442           MDS->getFlags(), MDS->getSPFlags(), Unit, TemplateParams, Declaration,
443           Variables);
444     };
445 
446     if (MDS->isDistinct())
447       return distinctMDSubprogram();
448 
449     auto *NewMDS = DISubprogram::get(
450         MDS->getContext(), FileAndScope, MDS->getName(), LinkageName,
451         FileAndScope, MDS->getLine(), Type, MDS->getScopeLine(), ContainingType,
452         MDS->getVirtualIndex(), MDS->getThisAdjustment(), MDS->getFlags(),
453         MDS->getSPFlags(), Unit, TemplateParams, Declaration, Variables);
454 
455     StringRef OldLinkageName = MDS->getLinkageName();
456 
457     // See if we need to make a distinct one.
458     auto OrigLinkage = NewToLinkageName.find(NewMDS);
459     if (OrigLinkage != NewToLinkageName.end()) {
460       if (OrigLinkage->second == OldLinkageName)
461         // We're good.
462         return NewMDS;
463 
464       // Otherwise, need to make a distinct one.
465       // TODO: Query the map to see if we already have one.
466       return distinctMDSubprogram();
467     }
468 
469     NewToLinkageName.insert({NewMDS, MDS->getLinkageName()});
470     return NewMDS;
471   }
472 
473   /// Create a new compile unit, to replace the one given
474   DICompileUnit *getReplacementCU(DICompileUnit *CU) {
475     // Drop skeleton CUs.
476     if (CU->getDWOId())
477       return nullptr;
478 
479     auto *File = cast_or_null<DIFile>(map(CU->getFile()));
480     MDTuple *EnumTypes = nullptr;
481     MDTuple *RetainedTypes = nullptr;
482     MDTuple *GlobalVariables = nullptr;
483     MDTuple *ImportedEntities = nullptr;
484     return DICompileUnit::getDistinct(
485         CU->getContext(), CU->getSourceLanguage(), File, CU->getProducer(),
486         CU->isOptimized(), CU->getFlags(), CU->getRuntimeVersion(),
487         CU->getSplitDebugFilename(), DICompileUnit::LineTablesOnly, EnumTypes,
488         RetainedTypes, GlobalVariables, ImportedEntities, CU->getMacros(),
489         CU->getDWOId(), CU->getSplitDebugInlining(),
490         CU->getDebugInfoForProfiling(), CU->getNameTableKind(),
491         CU->getRangesBaseAddress(), CU->getSysRoot(), CU->getSDK());
492   }
493 
494   DILocation *getReplacementMDLocation(DILocation *MLD) {
495     auto *Scope = map(MLD->getScope());
496     auto *InlinedAt = map(MLD->getInlinedAt());
497     if (MLD->isDistinct())
498       return DILocation::getDistinct(MLD->getContext(), MLD->getLine(),
499                                      MLD->getColumn(), Scope, InlinedAt);
500     return DILocation::get(MLD->getContext(), MLD->getLine(), MLD->getColumn(),
501                            Scope, InlinedAt);
502   }
503 
504   /// Create a new generic MDNode, to replace the one given
505   MDNode *getReplacementMDNode(MDNode *N) {
506     SmallVector<Metadata *, 8> Ops;
507     Ops.reserve(N->getNumOperands());
508     for (auto &I : N->operands())
509       if (I)
510         Ops.push_back(map(I));
511     auto *Ret = MDNode::get(N->getContext(), Ops);
512     return Ret;
513   }
514 
515   /// Attempt to re-map N to a newly created node.
516   void remap(MDNode *N) {
517     if (Replacements.count(N))
518       return;
519 
520     auto doRemap = [&](MDNode *N) -> MDNode * {
521       if (!N)
522         return nullptr;
523       if (auto *MDSub = dyn_cast<DISubprogram>(N)) {
524         remap(MDSub->getUnit());
525         return getReplacementSubprogram(MDSub);
526       }
527       if (isa<DISubroutineType>(N))
528         return EmptySubroutineType;
529       if (auto *CU = dyn_cast<DICompileUnit>(N))
530         return getReplacementCU(CU);
531       if (isa<DIFile>(N))
532         return N;
533       if (auto *MDLB = dyn_cast<DILexicalBlockBase>(N))
534         // Remap to our referenced scope (recursively).
535         return mapNode(MDLB->getScope());
536       if (auto *MLD = dyn_cast<DILocation>(N))
537         return getReplacementMDLocation(MLD);
538 
539       // Otherwise, if we see these, just drop them now. Not strictly necessary,
540       // but this speeds things up a little.
541       if (isa<DINode>(N))
542         return nullptr;
543 
544       return getReplacementMDNode(N);
545     };
546     Replacements[N] = doRemap(N);
547   }
548 
549   /// Do the remapping traversal.
550   void traverse(MDNode *);
551 };
552 
553 } // end anonymous namespace
554 
555 void DebugTypeInfoRemoval::traverse(MDNode *N) {
556   if (!N || Replacements.count(N))
557     return;
558 
559   // To avoid cycles, as well as for efficiency sake, we will sometimes prune
560   // parts of the graph.
561   auto prune = [](MDNode *Parent, MDNode *Child) {
562     if (auto *MDS = dyn_cast<DISubprogram>(Parent))
563       return Child == MDS->getRetainedNodes().get();
564     return false;
565   };
566 
567   SmallVector<MDNode *, 16> ToVisit;
568   DenseSet<MDNode *> Opened;
569 
570   // Visit each node starting at N in post order, and map them.
571   ToVisit.push_back(N);
572   while (!ToVisit.empty()) {
573     auto *N = ToVisit.back();
574     if (!Opened.insert(N).second) {
575       // Close it.
576       remap(N);
577       ToVisit.pop_back();
578       continue;
579     }
580     for (auto &I : N->operands())
581       if (auto *MDN = dyn_cast_or_null<MDNode>(I))
582         if (!Opened.count(MDN) && !Replacements.count(MDN) && !prune(N, MDN) &&
583             !isa<DICompileUnit>(MDN))
584           ToVisit.push_back(MDN);
585   }
586 }
587 
588 bool llvm::stripNonLineTableDebugInfo(Module &M) {
589   bool Changed = false;
590 
591   // First off, delete the debug intrinsics.
592   auto RemoveUses = [&](StringRef Name) {
593     if (auto *DbgVal = M.getFunction(Name)) {
594       while (!DbgVal->use_empty())
595         cast<Instruction>(DbgVal->user_back())->eraseFromParent();
596       DbgVal->eraseFromParent();
597       Changed = true;
598     }
599   };
600   RemoveUses("llvm.dbg.addr");
601   RemoveUses("llvm.dbg.declare");
602   RemoveUses("llvm.dbg.label");
603   RemoveUses("llvm.dbg.value");
604 
605   // Delete non-CU debug info named metadata nodes.
606   for (auto NMI = M.named_metadata_begin(), NME = M.named_metadata_end();
607        NMI != NME;) {
608     NamedMDNode *NMD = &*NMI;
609     ++NMI;
610     // Specifically keep dbg.cu around.
611     if (NMD->getName() == "llvm.dbg.cu")
612       continue;
613   }
614 
615   // Drop all dbg attachments from global variables.
616   for (auto &GV : M.globals())
617     GV.eraseMetadata(LLVMContext::MD_dbg);
618 
619   DebugTypeInfoRemoval Mapper(M.getContext());
620   auto remap = [&](MDNode *Node) -> MDNode * {
621     if (!Node)
622       return nullptr;
623     Mapper.traverseAndRemap(Node);
624     auto *NewNode = Mapper.mapNode(Node);
625     Changed |= Node != NewNode;
626     Node = NewNode;
627     return NewNode;
628   };
629 
630   // Rewrite the DebugLocs to be equivalent to what
631   // -gline-tables-only would have created.
632   for (auto &F : M) {
633     if (auto *SP = F.getSubprogram()) {
634       Mapper.traverseAndRemap(SP);
635       auto *NewSP = cast<DISubprogram>(Mapper.mapNode(SP));
636       Changed |= SP != NewSP;
637       F.setSubprogram(NewSP);
638     }
639     for (auto &BB : F) {
640       for (auto &I : BB) {
641         auto remapDebugLoc = [&](const DebugLoc &DL) -> DebugLoc {
642           auto *Scope = DL.getScope();
643           MDNode *InlinedAt = DL.getInlinedAt();
644           Scope = remap(Scope);
645           InlinedAt = remap(InlinedAt);
646           return DILocation::get(M.getContext(), DL.getLine(), DL.getCol(),
647                                  Scope, InlinedAt);
648         };
649 
650         if (I.getDebugLoc() != DebugLoc())
651           I.setDebugLoc(remapDebugLoc(I.getDebugLoc()));
652 
653         // Remap DILocations in llvm.loop attachments.
654         updateLoopMetadataDebugLocations(I, [&](const DILocation &Loc) {
655           return remapDebugLoc(&Loc).get();
656         });
657       }
658     }
659   }
660 
661   // Create a new llvm.dbg.cu, which is equivalent to the one
662   // -gline-tables-only would have created.
663   for (auto &NMD : M.getNamedMDList()) {
664     SmallVector<MDNode *, 8> Ops;
665     for (MDNode *Op : NMD.operands())
666       Ops.push_back(remap(Op));
667 
668     if (!Changed)
669       continue;
670 
671     NMD.clearOperands();
672     for (auto *Op : Ops)
673       if (Op)
674         NMD.addOperand(Op);
675   }
676   return Changed;
677 }
678 
679 unsigned llvm::getDebugMetadataVersionFromModule(const Module &M) {
680   if (auto *Val = mdconst::dyn_extract_or_null<ConstantInt>(
681           M.getModuleFlag("Debug Info Version")))
682     return Val->getZExtValue();
683   return 0;
684 }
685 
686 void Instruction::applyMergedLocation(const DILocation *LocA,
687                                       const DILocation *LocB) {
688   setDebugLoc(DILocation::getMergedLocation(LocA, LocB));
689 }
690 
691 void Instruction::updateLocationAfterHoist() { dropLocation(); }
692 
693 void Instruction::dropLocation() {
694   const DebugLoc &DL = getDebugLoc();
695   if (!DL)
696     return;
697 
698   // If this isn't a call, drop the location to allow a location from a
699   // preceding instruction to propagate.
700   if (!isa<CallBase>(this)) {
701     setDebugLoc(DebugLoc());
702     return;
703   }
704 
705   // Set a line 0 location for calls to preserve scope information in case
706   // inlining occurs.
707   DISubprogram *SP = getFunction()->getSubprogram();
708   if (SP)
709     // If a function scope is available, set it on the line 0 location. When
710     // hoisting a call to a predecessor block, using the function scope avoids
711     // making it look like the callee was reached earlier than it should be.
712     setDebugLoc(DILocation::get(getContext(), 0, 0, SP));
713   else
714     // The parent function has no scope. Go ahead and drop the location. If
715     // the parent function is inlined, and the callee has a subprogram, the
716     // inliner will attach a location to the call.
717     //
718     // One alternative is to set a line 0 location with the existing scope and
719     // inlinedAt info. The location might be sensitive to when inlining occurs.
720     setDebugLoc(DebugLoc());
721 }
722 
723 //===----------------------------------------------------------------------===//
724 // LLVM C API implementations.
725 //===----------------------------------------------------------------------===//
726 
727 static unsigned map_from_llvmDWARFsourcelanguage(LLVMDWARFSourceLanguage lang) {
728   switch (lang) {
729 #define HANDLE_DW_LANG(ID, NAME, LOWER_BOUND, VERSION, VENDOR)                 \
730   case LLVMDWARFSourceLanguage##NAME:                                          \
731     return ID;
732 #include "llvm/BinaryFormat/Dwarf.def"
733 #undef HANDLE_DW_LANG
734   }
735   llvm_unreachable("Unhandled Tag");
736 }
737 
738 template <typename DIT> DIT *unwrapDI(LLVMMetadataRef Ref) {
739   return (DIT *)(Ref ? unwrap<MDNode>(Ref) : nullptr);
740 }
741 
742 static DINode::DIFlags map_from_llvmDIFlags(LLVMDIFlags Flags) {
743   return static_cast<DINode::DIFlags>(Flags);
744 }
745 
746 static LLVMDIFlags map_to_llvmDIFlags(DINode::DIFlags Flags) {
747   return static_cast<LLVMDIFlags>(Flags);
748 }
749 
750 static DISubprogram::DISPFlags
751 pack_into_DISPFlags(bool IsLocalToUnit, bool IsDefinition, bool IsOptimized) {
752   return DISubprogram::toSPFlags(IsLocalToUnit, IsDefinition, IsOptimized);
753 }
754 
755 unsigned LLVMDebugMetadataVersion() {
756   return DEBUG_METADATA_VERSION;
757 }
758 
759 LLVMDIBuilderRef LLVMCreateDIBuilderDisallowUnresolved(LLVMModuleRef M) {
760   return wrap(new DIBuilder(*unwrap(M), false));
761 }
762 
763 LLVMDIBuilderRef LLVMCreateDIBuilder(LLVMModuleRef M) {
764   return wrap(new DIBuilder(*unwrap(M)));
765 }
766 
767 unsigned LLVMGetModuleDebugMetadataVersion(LLVMModuleRef M) {
768   return getDebugMetadataVersionFromModule(*unwrap(M));
769 }
770 
771 LLVMBool LLVMStripModuleDebugInfo(LLVMModuleRef M) {
772   return StripDebugInfo(*unwrap(M));
773 }
774 
775 void LLVMDisposeDIBuilder(LLVMDIBuilderRef Builder) {
776   delete unwrap(Builder);
777 }
778 
779 void LLVMDIBuilderFinalize(LLVMDIBuilderRef Builder) {
780   unwrap(Builder)->finalize();
781 }
782 
783 LLVMMetadataRef LLVMDIBuilderCreateCompileUnit(
784     LLVMDIBuilderRef Builder, LLVMDWARFSourceLanguage Lang,
785     LLVMMetadataRef FileRef, const char *Producer, size_t ProducerLen,
786     LLVMBool isOptimized, const char *Flags, size_t FlagsLen,
787     unsigned RuntimeVer, const char *SplitName, size_t SplitNameLen,
788     LLVMDWARFEmissionKind Kind, unsigned DWOId, LLVMBool SplitDebugInlining,
789     LLVMBool DebugInfoForProfiling, const char *SysRoot, size_t SysRootLen,
790     const char *SDK, size_t SDKLen) {
791   auto File = unwrapDI<DIFile>(FileRef);
792 
793   return wrap(unwrap(Builder)->createCompileUnit(
794       map_from_llvmDWARFsourcelanguage(Lang), File,
795       StringRef(Producer, ProducerLen), isOptimized, StringRef(Flags, FlagsLen),
796       RuntimeVer, StringRef(SplitName, SplitNameLen),
797       static_cast<DICompileUnit::DebugEmissionKind>(Kind), DWOId,
798       SplitDebugInlining, DebugInfoForProfiling,
799       DICompileUnit::DebugNameTableKind::Default, false,
800       StringRef(SysRoot, SysRootLen), StringRef(SDK, SDKLen)));
801 }
802 
803 LLVMMetadataRef
804 LLVMDIBuilderCreateFile(LLVMDIBuilderRef Builder, const char *Filename,
805                         size_t FilenameLen, const char *Directory,
806                         size_t DirectoryLen) {
807   return wrap(unwrap(Builder)->createFile(StringRef(Filename, FilenameLen),
808                                           StringRef(Directory, DirectoryLen)));
809 }
810 
811 LLVMMetadataRef
812 LLVMDIBuilderCreateModule(LLVMDIBuilderRef Builder, LLVMMetadataRef ParentScope,
813                           const char *Name, size_t NameLen,
814                           const char *ConfigMacros, size_t ConfigMacrosLen,
815                           const char *IncludePath, size_t IncludePathLen,
816                           const char *APINotesFile, size_t APINotesFileLen) {
817   return wrap(unwrap(Builder)->createModule(
818       unwrapDI<DIScope>(ParentScope), StringRef(Name, NameLen),
819       StringRef(ConfigMacros, ConfigMacrosLen),
820       StringRef(IncludePath, IncludePathLen),
821       StringRef(APINotesFile, APINotesFileLen)));
822 }
823 
824 LLVMMetadataRef LLVMDIBuilderCreateNameSpace(LLVMDIBuilderRef Builder,
825                                              LLVMMetadataRef ParentScope,
826                                              const char *Name, size_t NameLen,
827                                              LLVMBool ExportSymbols) {
828   return wrap(unwrap(Builder)->createNameSpace(
829       unwrapDI<DIScope>(ParentScope), StringRef(Name, NameLen), ExportSymbols));
830 }
831 
832 LLVMMetadataRef LLVMDIBuilderCreateFunction(
833     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
834     size_t NameLen, const char *LinkageName, size_t LinkageNameLen,
835     LLVMMetadataRef File, unsigned LineNo, LLVMMetadataRef Ty,
836     LLVMBool IsLocalToUnit, LLVMBool IsDefinition,
837     unsigned ScopeLine, LLVMDIFlags Flags, LLVMBool IsOptimized) {
838   return wrap(unwrap(Builder)->createFunction(
839       unwrapDI<DIScope>(Scope), {Name, NameLen}, {LinkageName, LinkageNameLen},
840       unwrapDI<DIFile>(File), LineNo, unwrapDI<DISubroutineType>(Ty), ScopeLine,
841       map_from_llvmDIFlags(Flags),
842       pack_into_DISPFlags(IsLocalToUnit, IsDefinition, IsOptimized), nullptr,
843       nullptr, nullptr));
844 }
845 
846 
847 LLVMMetadataRef LLVMDIBuilderCreateLexicalBlock(
848     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope,
849     LLVMMetadataRef File, unsigned Line, unsigned Col) {
850   return wrap(unwrap(Builder)->createLexicalBlock(unwrapDI<DIScope>(Scope),
851                                                   unwrapDI<DIFile>(File),
852                                                   Line, Col));
853 }
854 
855 LLVMMetadataRef
856 LLVMDIBuilderCreateLexicalBlockFile(LLVMDIBuilderRef Builder,
857                                     LLVMMetadataRef Scope,
858                                     LLVMMetadataRef File,
859                                     unsigned Discriminator) {
860   return wrap(unwrap(Builder)->createLexicalBlockFile(unwrapDI<DIScope>(Scope),
861                                                       unwrapDI<DIFile>(File),
862                                                       Discriminator));
863 }
864 
865 LLVMMetadataRef
866 LLVMDIBuilderCreateImportedModuleFromNamespace(LLVMDIBuilderRef Builder,
867                                                LLVMMetadataRef Scope,
868                                                LLVMMetadataRef NS,
869                                                LLVMMetadataRef File,
870                                                unsigned Line) {
871   return wrap(unwrap(Builder)->createImportedModule(unwrapDI<DIScope>(Scope),
872                                                     unwrapDI<DINamespace>(NS),
873                                                     unwrapDI<DIFile>(File),
874                                                     Line));
875 }
876 
877 LLVMMetadataRef
878 LLVMDIBuilderCreateImportedModuleFromAlias(LLVMDIBuilderRef Builder,
879                                            LLVMMetadataRef Scope,
880                                            LLVMMetadataRef ImportedEntity,
881                                            LLVMMetadataRef File,
882                                            unsigned Line) {
883   return wrap(unwrap(Builder)->createImportedModule(
884                   unwrapDI<DIScope>(Scope),
885                   unwrapDI<DIImportedEntity>(ImportedEntity),
886                   unwrapDI<DIFile>(File), Line));
887 }
888 
889 LLVMMetadataRef
890 LLVMDIBuilderCreateImportedModuleFromModule(LLVMDIBuilderRef Builder,
891                                             LLVMMetadataRef Scope,
892                                             LLVMMetadataRef M,
893                                             LLVMMetadataRef File,
894                                             unsigned Line) {
895   return wrap(unwrap(Builder)->createImportedModule(unwrapDI<DIScope>(Scope),
896                                                     unwrapDI<DIModule>(M),
897                                                     unwrapDI<DIFile>(File),
898                                                     Line));
899 }
900 
901 LLVMMetadataRef
902 LLVMDIBuilderCreateImportedDeclaration(LLVMDIBuilderRef Builder,
903                                        LLVMMetadataRef Scope,
904                                        LLVMMetadataRef Decl,
905                                        LLVMMetadataRef File,
906                                        unsigned Line,
907                                        const char *Name, size_t NameLen) {
908   return wrap(unwrap(Builder)->createImportedDeclaration(
909                   unwrapDI<DIScope>(Scope),
910                   unwrapDI<DINode>(Decl),
911                   unwrapDI<DIFile>(File), Line, {Name, NameLen}));
912 }
913 
914 LLVMMetadataRef
915 LLVMDIBuilderCreateDebugLocation(LLVMContextRef Ctx, unsigned Line,
916                                  unsigned Column, LLVMMetadataRef Scope,
917                                  LLVMMetadataRef InlinedAt) {
918   return wrap(DILocation::get(*unwrap(Ctx), Line, Column, unwrap(Scope),
919                               unwrap(InlinedAt)));
920 }
921 
922 unsigned LLVMDILocationGetLine(LLVMMetadataRef Location) {
923   return unwrapDI<DILocation>(Location)->getLine();
924 }
925 
926 unsigned LLVMDILocationGetColumn(LLVMMetadataRef Location) {
927   return unwrapDI<DILocation>(Location)->getColumn();
928 }
929 
930 LLVMMetadataRef LLVMDILocationGetScope(LLVMMetadataRef Location) {
931   return wrap(unwrapDI<DILocation>(Location)->getScope());
932 }
933 
934 LLVMMetadataRef LLVMDILocationGetInlinedAt(LLVMMetadataRef Location) {
935   return wrap(unwrapDI<DILocation>(Location)->getInlinedAt());
936 }
937 
938 LLVMMetadataRef LLVMDIScopeGetFile(LLVMMetadataRef Scope) {
939   return wrap(unwrapDI<DIScope>(Scope)->getFile());
940 }
941 
942 const char *LLVMDIFileGetDirectory(LLVMMetadataRef File, unsigned *Len) {
943   auto Dir = unwrapDI<DIFile>(File)->getDirectory();
944   *Len = Dir.size();
945   return Dir.data();
946 }
947 
948 const char *LLVMDIFileGetFilename(LLVMMetadataRef File, unsigned *Len) {
949   auto Name = unwrapDI<DIFile>(File)->getFilename();
950   *Len = Name.size();
951   return Name.data();
952 }
953 
954 const char *LLVMDIFileGetSource(LLVMMetadataRef File, unsigned *Len) {
955   if (auto Src = unwrapDI<DIFile>(File)->getSource()) {
956     *Len = Src->size();
957     return Src->data();
958   }
959   *Len = 0;
960   return "";
961 }
962 
963 LLVMMetadataRef LLVMDIBuilderCreateMacro(LLVMDIBuilderRef Builder,
964                                          LLVMMetadataRef ParentMacroFile,
965                                          unsigned Line,
966                                          LLVMDWARFMacinfoRecordType RecordType,
967                                          const char *Name, size_t NameLen,
968                                          const char *Value, size_t ValueLen) {
969   return wrap(
970       unwrap(Builder)->createMacro(unwrapDI<DIMacroFile>(ParentMacroFile), Line,
971                                    static_cast<MacinfoRecordType>(RecordType),
972                                    {Name, NameLen}, {Value, ValueLen}));
973 }
974 
975 LLVMMetadataRef
976 LLVMDIBuilderCreateTempMacroFile(LLVMDIBuilderRef Builder,
977                                  LLVMMetadataRef ParentMacroFile, unsigned Line,
978                                  LLVMMetadataRef File) {
979   return wrap(unwrap(Builder)->createTempMacroFile(
980       unwrapDI<DIMacroFile>(ParentMacroFile), Line, unwrapDI<DIFile>(File)));
981 }
982 
983 LLVMMetadataRef LLVMDIBuilderCreateEnumerator(LLVMDIBuilderRef Builder,
984                                               const char *Name, size_t NameLen,
985                                               int64_t Value,
986                                               LLVMBool IsUnsigned) {
987   return wrap(unwrap(Builder)->createEnumerator({Name, NameLen}, Value,
988                                                 IsUnsigned != 0));
989 }
990 
991 LLVMMetadataRef LLVMDIBuilderCreateEnumerationType(
992   LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
993   size_t NameLen, LLVMMetadataRef File, unsigned LineNumber,
994   uint64_t SizeInBits, uint32_t AlignInBits, LLVMMetadataRef *Elements,
995   unsigned NumElements, LLVMMetadataRef ClassTy) {
996 auto Elts = unwrap(Builder)->getOrCreateArray({unwrap(Elements),
997                                                NumElements});
998 return wrap(unwrap(Builder)->createEnumerationType(
999     unwrapDI<DIScope>(Scope), {Name, NameLen}, unwrapDI<DIFile>(File),
1000     LineNumber, SizeInBits, AlignInBits, Elts, unwrapDI<DIType>(ClassTy)));
1001 }
1002 
1003 LLVMMetadataRef LLVMDIBuilderCreateUnionType(
1004   LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1005   size_t NameLen, LLVMMetadataRef File, unsigned LineNumber,
1006   uint64_t SizeInBits, uint32_t AlignInBits, LLVMDIFlags Flags,
1007   LLVMMetadataRef *Elements, unsigned NumElements, unsigned RunTimeLang,
1008   const char *UniqueId, size_t UniqueIdLen) {
1009   auto Elts = unwrap(Builder)->getOrCreateArray({unwrap(Elements),
1010                                                  NumElements});
1011   return wrap(unwrap(Builder)->createUnionType(
1012      unwrapDI<DIScope>(Scope), {Name, NameLen}, unwrapDI<DIFile>(File),
1013      LineNumber, SizeInBits, AlignInBits, map_from_llvmDIFlags(Flags),
1014      Elts, RunTimeLang, {UniqueId, UniqueIdLen}));
1015 }
1016 
1017 
1018 LLVMMetadataRef
1019 LLVMDIBuilderCreateArrayType(LLVMDIBuilderRef Builder, uint64_t Size,
1020                              uint32_t AlignInBits, LLVMMetadataRef Ty,
1021                              LLVMMetadataRef *Subscripts,
1022                              unsigned NumSubscripts) {
1023   auto Subs = unwrap(Builder)->getOrCreateArray({unwrap(Subscripts),
1024                                                  NumSubscripts});
1025   return wrap(unwrap(Builder)->createArrayType(Size, AlignInBits,
1026                                                unwrapDI<DIType>(Ty), Subs));
1027 }
1028 
1029 LLVMMetadataRef
1030 LLVMDIBuilderCreateVectorType(LLVMDIBuilderRef Builder, uint64_t Size,
1031                               uint32_t AlignInBits, LLVMMetadataRef Ty,
1032                               LLVMMetadataRef *Subscripts,
1033                               unsigned NumSubscripts) {
1034   auto Subs = unwrap(Builder)->getOrCreateArray({unwrap(Subscripts),
1035                                                  NumSubscripts});
1036   return wrap(unwrap(Builder)->createVectorType(Size, AlignInBits,
1037                                                 unwrapDI<DIType>(Ty), Subs));
1038 }
1039 
1040 LLVMMetadataRef
1041 LLVMDIBuilderCreateBasicType(LLVMDIBuilderRef Builder, const char *Name,
1042                              size_t NameLen, uint64_t SizeInBits,
1043                              LLVMDWARFTypeEncoding Encoding,
1044                              LLVMDIFlags Flags) {
1045   return wrap(unwrap(Builder)->createBasicType({Name, NameLen},
1046                                                SizeInBits, Encoding,
1047                                                map_from_llvmDIFlags(Flags)));
1048 }
1049 
1050 LLVMMetadataRef LLVMDIBuilderCreatePointerType(
1051     LLVMDIBuilderRef Builder, LLVMMetadataRef PointeeTy,
1052     uint64_t SizeInBits, uint32_t AlignInBits, unsigned AddressSpace,
1053     const char *Name, size_t NameLen) {
1054   return wrap(unwrap(Builder)->createPointerType(unwrapDI<DIType>(PointeeTy),
1055                                          SizeInBits, AlignInBits,
1056                                          AddressSpace, {Name, NameLen}));
1057 }
1058 
1059 LLVMMetadataRef LLVMDIBuilderCreateStructType(
1060     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1061     size_t NameLen, LLVMMetadataRef File, unsigned LineNumber,
1062     uint64_t SizeInBits, uint32_t AlignInBits, LLVMDIFlags Flags,
1063     LLVMMetadataRef DerivedFrom, LLVMMetadataRef *Elements,
1064     unsigned NumElements, unsigned RunTimeLang, LLVMMetadataRef VTableHolder,
1065     const char *UniqueId, size_t UniqueIdLen) {
1066   auto Elts = unwrap(Builder)->getOrCreateArray({unwrap(Elements),
1067                                                  NumElements});
1068   return wrap(unwrap(Builder)->createStructType(
1069       unwrapDI<DIScope>(Scope), {Name, NameLen}, unwrapDI<DIFile>(File),
1070       LineNumber, SizeInBits, AlignInBits, map_from_llvmDIFlags(Flags),
1071       unwrapDI<DIType>(DerivedFrom), Elts, RunTimeLang,
1072       unwrapDI<DIType>(VTableHolder), {UniqueId, UniqueIdLen}));
1073 }
1074 
1075 LLVMMetadataRef LLVMDIBuilderCreateMemberType(
1076     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1077     size_t NameLen, LLVMMetadataRef File, unsigned LineNo, uint64_t SizeInBits,
1078     uint32_t AlignInBits, uint64_t OffsetInBits, LLVMDIFlags Flags,
1079     LLVMMetadataRef Ty) {
1080   return wrap(unwrap(Builder)->createMemberType(unwrapDI<DIScope>(Scope),
1081       {Name, NameLen}, unwrapDI<DIFile>(File), LineNo, SizeInBits, AlignInBits,
1082       OffsetInBits, map_from_llvmDIFlags(Flags), unwrapDI<DIType>(Ty)));
1083 }
1084 
1085 LLVMMetadataRef
1086 LLVMDIBuilderCreateUnspecifiedType(LLVMDIBuilderRef Builder, const char *Name,
1087                                    size_t NameLen) {
1088   return wrap(unwrap(Builder)->createUnspecifiedType({Name, NameLen}));
1089 }
1090 
1091 LLVMMetadataRef
1092 LLVMDIBuilderCreateStaticMemberType(
1093     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1094     size_t NameLen, LLVMMetadataRef File, unsigned LineNumber,
1095     LLVMMetadataRef Type, LLVMDIFlags Flags, LLVMValueRef ConstantVal,
1096     uint32_t AlignInBits) {
1097   return wrap(unwrap(Builder)->createStaticMemberType(
1098                   unwrapDI<DIScope>(Scope), {Name, NameLen},
1099                   unwrapDI<DIFile>(File), LineNumber, unwrapDI<DIType>(Type),
1100                   map_from_llvmDIFlags(Flags), unwrap<Constant>(ConstantVal),
1101                   AlignInBits));
1102 }
1103 
1104 LLVMMetadataRef
1105 LLVMDIBuilderCreateObjCIVar(LLVMDIBuilderRef Builder,
1106                             const char *Name, size_t NameLen,
1107                             LLVMMetadataRef File, unsigned LineNo,
1108                             uint64_t SizeInBits, uint32_t AlignInBits,
1109                             uint64_t OffsetInBits, LLVMDIFlags Flags,
1110                             LLVMMetadataRef Ty, LLVMMetadataRef PropertyNode) {
1111   return wrap(unwrap(Builder)->createObjCIVar(
1112                   {Name, NameLen}, unwrapDI<DIFile>(File), LineNo,
1113                   SizeInBits, AlignInBits, OffsetInBits,
1114                   map_from_llvmDIFlags(Flags), unwrapDI<DIType>(Ty),
1115                   unwrapDI<MDNode>(PropertyNode)));
1116 }
1117 
1118 LLVMMetadataRef
1119 LLVMDIBuilderCreateObjCProperty(LLVMDIBuilderRef Builder,
1120                                 const char *Name, size_t NameLen,
1121                                 LLVMMetadataRef File, unsigned LineNo,
1122                                 const char *GetterName, size_t GetterNameLen,
1123                                 const char *SetterName, size_t SetterNameLen,
1124                                 unsigned PropertyAttributes,
1125                                 LLVMMetadataRef Ty) {
1126   return wrap(unwrap(Builder)->createObjCProperty(
1127                   {Name, NameLen}, unwrapDI<DIFile>(File), LineNo,
1128                   {GetterName, GetterNameLen}, {SetterName, SetterNameLen},
1129                   PropertyAttributes, unwrapDI<DIType>(Ty)));
1130 }
1131 
1132 LLVMMetadataRef
1133 LLVMDIBuilderCreateObjectPointerType(LLVMDIBuilderRef Builder,
1134                                      LLVMMetadataRef Type) {
1135   return wrap(unwrap(Builder)->createObjectPointerType(unwrapDI<DIType>(Type)));
1136 }
1137 
1138 LLVMMetadataRef
1139 LLVMDIBuilderCreateTypedef(LLVMDIBuilderRef Builder, LLVMMetadataRef Type,
1140                            const char *Name, size_t NameLen,
1141                            LLVMMetadataRef File, unsigned LineNo,
1142                            LLVMMetadataRef Scope, uint32_t AlignInBits) {
1143   return wrap(unwrap(Builder)->createTypedef(
1144       unwrapDI<DIType>(Type), {Name, NameLen}, unwrapDI<DIFile>(File), LineNo,
1145       unwrapDI<DIScope>(Scope), AlignInBits));
1146 }
1147 
1148 LLVMMetadataRef
1149 LLVMDIBuilderCreateInheritance(LLVMDIBuilderRef Builder,
1150                                LLVMMetadataRef Ty, LLVMMetadataRef BaseTy,
1151                                uint64_t BaseOffset, uint32_t VBPtrOffset,
1152                                LLVMDIFlags Flags) {
1153   return wrap(unwrap(Builder)->createInheritance(
1154                   unwrapDI<DIType>(Ty), unwrapDI<DIType>(BaseTy),
1155                   BaseOffset, VBPtrOffset, map_from_llvmDIFlags(Flags)));
1156 }
1157 
1158 LLVMMetadataRef
1159 LLVMDIBuilderCreateForwardDecl(
1160     LLVMDIBuilderRef Builder, unsigned Tag, const char *Name,
1161     size_t NameLen, LLVMMetadataRef Scope, LLVMMetadataRef File, unsigned Line,
1162     unsigned RuntimeLang, uint64_t SizeInBits, uint32_t AlignInBits,
1163     const char *UniqueIdentifier, size_t UniqueIdentifierLen) {
1164   return wrap(unwrap(Builder)->createForwardDecl(
1165                   Tag, {Name, NameLen}, unwrapDI<DIScope>(Scope),
1166                   unwrapDI<DIFile>(File), Line, RuntimeLang, SizeInBits,
1167                   AlignInBits, {UniqueIdentifier, UniqueIdentifierLen}));
1168 }
1169 
1170 LLVMMetadataRef
1171 LLVMDIBuilderCreateReplaceableCompositeType(
1172     LLVMDIBuilderRef Builder, unsigned Tag, const char *Name,
1173     size_t NameLen, LLVMMetadataRef Scope, LLVMMetadataRef File, unsigned Line,
1174     unsigned RuntimeLang, uint64_t SizeInBits, uint32_t AlignInBits,
1175     LLVMDIFlags Flags, const char *UniqueIdentifier,
1176     size_t UniqueIdentifierLen) {
1177   return wrap(unwrap(Builder)->createReplaceableCompositeType(
1178                   Tag, {Name, NameLen}, unwrapDI<DIScope>(Scope),
1179                   unwrapDI<DIFile>(File), Line, RuntimeLang, SizeInBits,
1180                   AlignInBits, map_from_llvmDIFlags(Flags),
1181                   {UniqueIdentifier, UniqueIdentifierLen}));
1182 }
1183 
1184 LLVMMetadataRef
1185 LLVMDIBuilderCreateQualifiedType(LLVMDIBuilderRef Builder, unsigned Tag,
1186                                  LLVMMetadataRef Type) {
1187   return wrap(unwrap(Builder)->createQualifiedType(Tag,
1188                                                    unwrapDI<DIType>(Type)));
1189 }
1190 
1191 LLVMMetadataRef
1192 LLVMDIBuilderCreateReferenceType(LLVMDIBuilderRef Builder, unsigned Tag,
1193                                  LLVMMetadataRef Type) {
1194   return wrap(unwrap(Builder)->createReferenceType(Tag,
1195                                                    unwrapDI<DIType>(Type)));
1196 }
1197 
1198 LLVMMetadataRef
1199 LLVMDIBuilderCreateNullPtrType(LLVMDIBuilderRef Builder) {
1200   return wrap(unwrap(Builder)->createNullPtrType());
1201 }
1202 
1203 LLVMMetadataRef
1204 LLVMDIBuilderCreateMemberPointerType(LLVMDIBuilderRef Builder,
1205                                      LLVMMetadataRef PointeeType,
1206                                      LLVMMetadataRef ClassType,
1207                                      uint64_t SizeInBits,
1208                                      uint32_t AlignInBits,
1209                                      LLVMDIFlags Flags) {
1210   return wrap(unwrap(Builder)->createMemberPointerType(
1211                   unwrapDI<DIType>(PointeeType),
1212                   unwrapDI<DIType>(ClassType), AlignInBits, SizeInBits,
1213                   map_from_llvmDIFlags(Flags)));
1214 }
1215 
1216 LLVMMetadataRef
1217 LLVMDIBuilderCreateBitFieldMemberType(LLVMDIBuilderRef Builder,
1218                                       LLVMMetadataRef Scope,
1219                                       const char *Name, size_t NameLen,
1220                                       LLVMMetadataRef File, unsigned LineNumber,
1221                                       uint64_t SizeInBits,
1222                                       uint64_t OffsetInBits,
1223                                       uint64_t StorageOffsetInBits,
1224                                       LLVMDIFlags Flags, LLVMMetadataRef Type) {
1225   return wrap(unwrap(Builder)->createBitFieldMemberType(
1226                   unwrapDI<DIScope>(Scope), {Name, NameLen},
1227                   unwrapDI<DIFile>(File), LineNumber,
1228                   SizeInBits, OffsetInBits, StorageOffsetInBits,
1229                   map_from_llvmDIFlags(Flags), unwrapDI<DIType>(Type)));
1230 }
1231 
1232 LLVMMetadataRef LLVMDIBuilderCreateClassType(LLVMDIBuilderRef Builder,
1233     LLVMMetadataRef Scope, const char *Name, size_t NameLen,
1234     LLVMMetadataRef File, unsigned LineNumber, uint64_t SizeInBits,
1235     uint32_t AlignInBits, uint64_t OffsetInBits, LLVMDIFlags Flags,
1236     LLVMMetadataRef DerivedFrom,
1237     LLVMMetadataRef *Elements, unsigned NumElements,
1238     LLVMMetadataRef VTableHolder, LLVMMetadataRef TemplateParamsNode,
1239     const char *UniqueIdentifier, size_t UniqueIdentifierLen) {
1240   auto Elts = unwrap(Builder)->getOrCreateArray({unwrap(Elements),
1241                                                  NumElements});
1242   return wrap(unwrap(Builder)->createClassType(
1243                   unwrapDI<DIScope>(Scope), {Name, NameLen},
1244                   unwrapDI<DIFile>(File), LineNumber,
1245                   SizeInBits, AlignInBits, OffsetInBits,
1246                   map_from_llvmDIFlags(Flags), unwrapDI<DIType>(DerivedFrom),
1247                   Elts, unwrapDI<DIType>(VTableHolder),
1248                   unwrapDI<MDNode>(TemplateParamsNode),
1249                   {UniqueIdentifier, UniqueIdentifierLen}));
1250 }
1251 
1252 LLVMMetadataRef
1253 LLVMDIBuilderCreateArtificialType(LLVMDIBuilderRef Builder,
1254                                   LLVMMetadataRef Type) {
1255   return wrap(unwrap(Builder)->createArtificialType(unwrapDI<DIType>(Type)));
1256 }
1257 
1258 const char *LLVMDITypeGetName(LLVMMetadataRef DType, size_t *Length) {
1259   StringRef Str = unwrap<DIType>(DType)->getName();
1260   *Length = Str.size();
1261   return Str.data();
1262 }
1263 
1264 uint64_t LLVMDITypeGetSizeInBits(LLVMMetadataRef DType) {
1265   return unwrapDI<DIType>(DType)->getSizeInBits();
1266 }
1267 
1268 uint64_t LLVMDITypeGetOffsetInBits(LLVMMetadataRef DType) {
1269   return unwrapDI<DIType>(DType)->getOffsetInBits();
1270 }
1271 
1272 uint32_t LLVMDITypeGetAlignInBits(LLVMMetadataRef DType) {
1273   return unwrapDI<DIType>(DType)->getAlignInBits();
1274 }
1275 
1276 unsigned LLVMDITypeGetLine(LLVMMetadataRef DType) {
1277   return unwrapDI<DIType>(DType)->getLine();
1278 }
1279 
1280 LLVMDIFlags LLVMDITypeGetFlags(LLVMMetadataRef DType) {
1281   return map_to_llvmDIFlags(unwrapDI<DIType>(DType)->getFlags());
1282 }
1283 
1284 LLVMMetadataRef LLVMDIBuilderGetOrCreateTypeArray(LLVMDIBuilderRef Builder,
1285                                                   LLVMMetadataRef *Types,
1286                                                   size_t Length) {
1287   return wrap(
1288       unwrap(Builder)->getOrCreateTypeArray({unwrap(Types), Length}).get());
1289 }
1290 
1291 LLVMMetadataRef
1292 LLVMDIBuilderCreateSubroutineType(LLVMDIBuilderRef Builder,
1293                                   LLVMMetadataRef File,
1294                                   LLVMMetadataRef *ParameterTypes,
1295                                   unsigned NumParameterTypes,
1296                                   LLVMDIFlags Flags) {
1297   auto Elts = unwrap(Builder)->getOrCreateTypeArray({unwrap(ParameterTypes),
1298                                                      NumParameterTypes});
1299   return wrap(unwrap(Builder)->createSubroutineType(
1300     Elts, map_from_llvmDIFlags(Flags)));
1301 }
1302 
1303 LLVMMetadataRef LLVMDIBuilderCreateExpression(LLVMDIBuilderRef Builder,
1304                                               int64_t *Addr, size_t Length) {
1305   return wrap(unwrap(Builder)->createExpression(ArrayRef<int64_t>(Addr,
1306                                                                   Length)));
1307 }
1308 
1309 LLVMMetadataRef
1310 LLVMDIBuilderCreateConstantValueExpression(LLVMDIBuilderRef Builder,
1311                                            int64_t Value) {
1312   return wrap(unwrap(Builder)->createConstantValueExpression(Value));
1313 }
1314 
1315 LLVMMetadataRef LLVMDIBuilderCreateGlobalVariableExpression(
1316     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1317     size_t NameLen, const char *Linkage, size_t LinkLen, LLVMMetadataRef File,
1318     unsigned LineNo, LLVMMetadataRef Ty, LLVMBool LocalToUnit,
1319     LLVMMetadataRef Expr, LLVMMetadataRef Decl, uint32_t AlignInBits) {
1320   return wrap(unwrap(Builder)->createGlobalVariableExpression(
1321       unwrapDI<DIScope>(Scope), {Name, NameLen}, {Linkage, LinkLen},
1322       unwrapDI<DIFile>(File), LineNo, unwrapDI<DIType>(Ty), LocalToUnit,
1323       true, unwrap<DIExpression>(Expr), unwrapDI<MDNode>(Decl),
1324       nullptr, AlignInBits));
1325 }
1326 
1327 LLVMMetadataRef LLVMDIGlobalVariableExpressionGetVariable(LLVMMetadataRef GVE) {
1328   return wrap(unwrapDI<DIGlobalVariableExpression>(GVE)->getVariable());
1329 }
1330 
1331 LLVMMetadataRef LLVMDIGlobalVariableExpressionGetExpression(
1332     LLVMMetadataRef GVE) {
1333   return wrap(unwrapDI<DIGlobalVariableExpression>(GVE)->getExpression());
1334 }
1335 
1336 LLVMMetadataRef LLVMDIVariableGetFile(LLVMMetadataRef Var) {
1337   return wrap(unwrapDI<DIVariable>(Var)->getFile());
1338 }
1339 
1340 LLVMMetadataRef LLVMDIVariableGetScope(LLVMMetadataRef Var) {
1341   return wrap(unwrapDI<DIVariable>(Var)->getScope());
1342 }
1343 
1344 unsigned LLVMDIVariableGetLine(LLVMMetadataRef Var) {
1345   return unwrapDI<DIVariable>(Var)->getLine();
1346 }
1347 
1348 LLVMMetadataRef LLVMTemporaryMDNode(LLVMContextRef Ctx, LLVMMetadataRef *Data,
1349                                     size_t Count) {
1350   return wrap(
1351       MDTuple::getTemporary(*unwrap(Ctx), {unwrap(Data), Count}).release());
1352 }
1353 
1354 void LLVMDisposeTemporaryMDNode(LLVMMetadataRef TempNode) {
1355   MDNode::deleteTemporary(unwrapDI<MDNode>(TempNode));
1356 }
1357 
1358 void LLVMMetadataReplaceAllUsesWith(LLVMMetadataRef TargetMetadata,
1359                                     LLVMMetadataRef Replacement) {
1360   auto *Node = unwrapDI<MDNode>(TargetMetadata);
1361   Node->replaceAllUsesWith(unwrap<Metadata>(Replacement));
1362   MDNode::deleteTemporary(Node);
1363 }
1364 
1365 LLVMMetadataRef LLVMDIBuilderCreateTempGlobalVariableFwdDecl(
1366     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1367     size_t NameLen, const char *Linkage, size_t LnkLen, LLVMMetadataRef File,
1368     unsigned LineNo, LLVMMetadataRef Ty, LLVMBool LocalToUnit,
1369     LLVMMetadataRef Decl, uint32_t AlignInBits) {
1370   return wrap(unwrap(Builder)->createTempGlobalVariableFwdDecl(
1371       unwrapDI<DIScope>(Scope), {Name, NameLen}, {Linkage, LnkLen},
1372       unwrapDI<DIFile>(File), LineNo, unwrapDI<DIType>(Ty), LocalToUnit,
1373       unwrapDI<MDNode>(Decl), nullptr, AlignInBits));
1374 }
1375 
1376 LLVMValueRef
1377 LLVMDIBuilderInsertDeclareBefore(LLVMDIBuilderRef Builder, LLVMValueRef Storage,
1378                                  LLVMMetadataRef VarInfo, LLVMMetadataRef Expr,
1379                                  LLVMMetadataRef DL, LLVMValueRef Instr) {
1380   return wrap(unwrap(Builder)->insertDeclare(
1381                   unwrap(Storage), unwrap<DILocalVariable>(VarInfo),
1382                   unwrap<DIExpression>(Expr), unwrap<DILocation>(DL),
1383                   unwrap<Instruction>(Instr)));
1384 }
1385 
1386 LLVMValueRef LLVMDIBuilderInsertDeclareAtEnd(
1387     LLVMDIBuilderRef Builder, LLVMValueRef Storage, LLVMMetadataRef VarInfo,
1388     LLVMMetadataRef Expr, LLVMMetadataRef DL, LLVMBasicBlockRef Block) {
1389   return wrap(unwrap(Builder)->insertDeclare(
1390                   unwrap(Storage), unwrap<DILocalVariable>(VarInfo),
1391                   unwrap<DIExpression>(Expr), unwrap<DILocation>(DL),
1392                   unwrap(Block)));
1393 }
1394 
1395 LLVMValueRef LLVMDIBuilderInsertDbgValueBefore(LLVMDIBuilderRef Builder,
1396                                                LLVMValueRef Val,
1397                                                LLVMMetadataRef VarInfo,
1398                                                LLVMMetadataRef Expr,
1399                                                LLVMMetadataRef DebugLoc,
1400                                                LLVMValueRef Instr) {
1401   return wrap(unwrap(Builder)->insertDbgValueIntrinsic(
1402                   unwrap(Val), unwrap<DILocalVariable>(VarInfo),
1403                   unwrap<DIExpression>(Expr), unwrap<DILocation>(DebugLoc),
1404                   unwrap<Instruction>(Instr)));
1405 }
1406 
1407 LLVMValueRef LLVMDIBuilderInsertDbgValueAtEnd(LLVMDIBuilderRef Builder,
1408                                               LLVMValueRef Val,
1409                                               LLVMMetadataRef VarInfo,
1410                                               LLVMMetadataRef Expr,
1411                                               LLVMMetadataRef DebugLoc,
1412                                               LLVMBasicBlockRef Block) {
1413   return wrap(unwrap(Builder)->insertDbgValueIntrinsic(
1414                   unwrap(Val), unwrap<DILocalVariable>(VarInfo),
1415                   unwrap<DIExpression>(Expr), unwrap<DILocation>(DebugLoc),
1416                   unwrap(Block)));
1417 }
1418 
1419 LLVMMetadataRef LLVMDIBuilderCreateAutoVariable(
1420     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1421     size_t NameLen, LLVMMetadataRef File, unsigned LineNo, LLVMMetadataRef Ty,
1422     LLVMBool AlwaysPreserve, LLVMDIFlags Flags, uint32_t AlignInBits) {
1423   return wrap(unwrap(Builder)->createAutoVariable(
1424                   unwrap<DIScope>(Scope), {Name, NameLen}, unwrap<DIFile>(File),
1425                   LineNo, unwrap<DIType>(Ty), AlwaysPreserve,
1426                   map_from_llvmDIFlags(Flags), AlignInBits));
1427 }
1428 
1429 LLVMMetadataRef LLVMDIBuilderCreateParameterVariable(
1430     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
1431     size_t NameLen, unsigned ArgNo, LLVMMetadataRef File, unsigned LineNo,
1432     LLVMMetadataRef Ty, LLVMBool AlwaysPreserve, LLVMDIFlags Flags) {
1433   return wrap(unwrap(Builder)->createParameterVariable(
1434                   unwrap<DIScope>(Scope), {Name, NameLen}, ArgNo, unwrap<DIFile>(File),
1435                   LineNo, unwrap<DIType>(Ty), AlwaysPreserve,
1436                   map_from_llvmDIFlags(Flags)));
1437 }
1438 
1439 LLVMMetadataRef LLVMDIBuilderGetOrCreateSubrange(LLVMDIBuilderRef Builder,
1440                                                  int64_t Lo, int64_t Count) {
1441   return wrap(unwrap(Builder)->getOrCreateSubrange(Lo, Count));
1442 }
1443 
1444 LLVMMetadataRef LLVMDIBuilderGetOrCreateArray(LLVMDIBuilderRef Builder,
1445                                               LLVMMetadataRef *Data,
1446                                               size_t Length) {
1447   Metadata **DataValue = unwrap(Data);
1448   return wrap(unwrap(Builder)->getOrCreateArray({DataValue, Length}).get());
1449 }
1450 
1451 LLVMMetadataRef LLVMGetSubprogram(LLVMValueRef Func) {
1452   return wrap(unwrap<Function>(Func)->getSubprogram());
1453 }
1454 
1455 void LLVMSetSubprogram(LLVMValueRef Func, LLVMMetadataRef SP) {
1456   unwrap<Function>(Func)->setSubprogram(unwrap<DISubprogram>(SP));
1457 }
1458 
1459 unsigned LLVMDISubprogramGetLine(LLVMMetadataRef Subprogram) {
1460   return unwrapDI<DISubprogram>(Subprogram)->getLine();
1461 }
1462 
1463 LLVMMetadataRef LLVMInstructionGetDebugLoc(LLVMValueRef Inst) {
1464   return wrap(unwrap<Instruction>(Inst)->getDebugLoc().getAsMDNode());
1465 }
1466 
1467 void LLVMInstructionSetDebugLoc(LLVMValueRef Inst, LLVMMetadataRef Loc) {
1468   if (Loc)
1469     unwrap<Instruction>(Inst)->setDebugLoc(DebugLoc(unwrap<MDNode>(Loc)));
1470   else
1471     unwrap<Instruction>(Inst)->setDebugLoc(DebugLoc());
1472 }
1473 
1474 LLVMMetadataKind LLVMGetMetadataKind(LLVMMetadataRef Metadata) {
1475   switch(unwrap(Metadata)->getMetadataID()) {
1476 #define HANDLE_METADATA_LEAF(CLASS) \
1477   case Metadata::CLASS##Kind: \
1478     return (LLVMMetadataKind)LLVM##CLASS##MetadataKind;
1479 #include "llvm/IR/Metadata.def"
1480   default:
1481     return (LLVMMetadataKind)LLVMGenericDINodeMetadataKind;
1482   }
1483 }
1484