1 //===--- DIBuilder.cpp - Debug Information Builder ------------------------===//
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 DIBuilder.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/IR/DIBuilder.h"
15 #include "llvm/ADT/STLExtras.h"
16 #include "llvm/IR/Constants.h"
17 #include "llvm/IR/DebugInfo.h"
18 #include "llvm/IR/IntrinsicInst.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/Support/Debug.h"
21 #include "llvm/Support/Dwarf.h"
22 
23 using namespace llvm;
24 using namespace llvm::dwarf;
25 
26 static Constant *GetTagConstant(LLVMContext &VMContext, unsigned Tag) {
27   assert((Tag & LLVMDebugVersionMask) == 0 &&
28          "Tag too large for debug encoding!");
29   return ConstantInt::get(Type::getInt32Ty(VMContext), Tag | LLVMDebugVersion);
30 }
31 
32 DIBuilder::DIBuilder(Module &m)
33     : M(m), VMContext(M.getContext()), TempEnumTypes(nullptr),
34       TempRetainTypes(nullptr), TempSubprograms(nullptr), TempGVs(nullptr),
35       DeclareFn(nullptr), ValueFn(nullptr) {}
36 
37 /// finalize - Construct any deferred debug info descriptors.
38 void DIBuilder::finalize() {
39   DIArray Enums = getOrCreateArray(AllEnumTypes);
40   DIType(TempEnumTypes).replaceAllUsesWith(Enums);
41 
42   SmallVector<Value *, 16> RetainValues;
43   // Declarations and definitions of the same type may be retained. Some
44   // clients RAUW these pairs, leaving duplicates in the retained types
45   // list. Use a set to remove the duplicates while we transform the
46   // TrackingVHs back into Values.
47   SmallPtrSet<Value *, 16> RetainSet;
48   for (unsigned I = 0, E = AllRetainTypes.size(); I < E; I++)
49     if (RetainSet.insert(AllRetainTypes[I]))
50       RetainValues.push_back(AllRetainTypes[I]);
51   DIArray RetainTypes = getOrCreateArray(RetainValues);
52   DIType(TempRetainTypes).replaceAllUsesWith(RetainTypes);
53 
54   DIArray SPs = getOrCreateArray(AllSubprograms);
55   DIType(TempSubprograms).replaceAllUsesWith(SPs);
56   for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
57     DISubprogram SP(SPs.getElement(i));
58     SmallVector<Value *, 4> Variables;
59     if (NamedMDNode *NMD = getFnSpecificMDNode(M, SP)) {
60       for (unsigned ii = 0, ee = NMD->getNumOperands(); ii != ee; ++ii)
61         Variables.push_back(NMD->getOperand(ii));
62       NMD->eraseFromParent();
63     }
64     if (MDNode *Temp = SP.getVariablesNodes()) {
65       DIArray AV = getOrCreateArray(Variables);
66       DIType(Temp).replaceAllUsesWith(AV);
67     }
68   }
69 
70   DIArray GVs = getOrCreateArray(AllGVs);
71   DIType(TempGVs).replaceAllUsesWith(GVs);
72 
73   SmallVector<Value *, 16> RetainValuesI;
74   for (unsigned I = 0, E = AllImportedModules.size(); I < E; I++)
75     RetainValuesI.push_back(AllImportedModules[I]);
76   DIArray IMs = getOrCreateArray(RetainValuesI);
77   DIType(TempImportedModules).replaceAllUsesWith(IMs);
78 }
79 
80 /// getNonCompileUnitScope - If N is compile unit return NULL otherwise return
81 /// N.
82 static MDNode *getNonCompileUnitScope(MDNode *N) {
83   if (DIDescriptor(N).isCompileUnit())
84     return nullptr;
85   return N;
86 }
87 
88 static MDNode *createFilePathPair(LLVMContext &VMContext, StringRef Filename,
89                                   StringRef Directory) {
90   assert(!Filename.empty() && "Unable to create file without name");
91   Value *Pair[] = {
92     MDString::get(VMContext, Filename),
93     MDString::get(VMContext, Directory)
94   };
95   return MDNode::get(VMContext, Pair);
96 }
97 
98 /// createCompileUnit - A CompileUnit provides an anchor for all debugging
99 /// information generated during this instance of compilation.
100 DICompileUnit DIBuilder::createCompileUnit(unsigned Lang, StringRef Filename,
101                                            StringRef Directory,
102                                            StringRef Producer, bool isOptimized,
103                                            StringRef Flags, unsigned RunTimeVer,
104                                            StringRef SplitName,
105                                            DebugEmissionKind Kind,
106                                            bool EmitDebugInfo) {
107 
108   assert(((Lang <= dwarf::DW_LANG_OCaml && Lang >= dwarf::DW_LANG_C89) ||
109           (Lang <= dwarf::DW_LANG_hi_user && Lang >= dwarf::DW_LANG_lo_user)) &&
110          "Invalid Language tag");
111   assert(!Filename.empty() &&
112          "Unable to create compile unit without filename");
113   Value *TElts[] = { GetTagConstant(VMContext, DW_TAG_base_type) };
114   TempEnumTypes = MDNode::getTemporary(VMContext, TElts);
115 
116   TempRetainTypes = MDNode::getTemporary(VMContext, TElts);
117 
118   TempSubprograms = MDNode::getTemporary(VMContext, TElts);
119 
120   TempGVs = MDNode::getTemporary(VMContext, TElts);
121 
122   TempImportedModules = MDNode::getTemporary(VMContext, TElts);
123 
124   Value *Elts[] = {
125     GetTagConstant(VMContext, dwarf::DW_TAG_compile_unit),
126     createFilePathPair(VMContext, Filename, Directory),
127     ConstantInt::get(Type::getInt32Ty(VMContext), Lang),
128     MDString::get(VMContext, Producer),
129     ConstantInt::get(Type::getInt1Ty(VMContext), isOptimized),
130     MDString::get(VMContext, Flags),
131     ConstantInt::get(Type::getInt32Ty(VMContext), RunTimeVer),
132     TempEnumTypes,
133     TempRetainTypes,
134     TempSubprograms,
135     TempGVs,
136     TempImportedModules,
137     MDString::get(VMContext, SplitName),
138     ConstantInt::get(Type::getInt32Ty(VMContext), Kind)
139   };
140 
141   MDNode *CUNode = MDNode::get(VMContext, Elts);
142 
143   // Create a named metadata so that it is easier to find cu in a module.
144   // Note that we only generate this when the caller wants to actually
145   // emit debug information. When we are only interested in tracking
146   // source line locations throughout the backend, we prevent codegen from
147   // emitting debug info in the final output by not generating llvm.dbg.cu.
148   if (EmitDebugInfo) {
149     NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.cu");
150     NMD->addOperand(CUNode);
151   }
152 
153   return DICompileUnit(CUNode);
154 }
155 
156 static DIImportedEntity
157 createImportedModule(LLVMContext &C, dwarf::Tag Tag, DIScope Context,
158                      Value *NS, unsigned Line, StringRef Name,
159                      SmallVectorImpl<TrackingVH<MDNode>> &AllImportedModules) {
160   const MDNode *R;
161   if (Name.empty()) {
162     Value *Elts[] = {
163       GetTagConstant(C, Tag),
164       Context,
165       NS,
166       ConstantInt::get(Type::getInt32Ty(C), Line),
167     };
168     R = MDNode::get(C, Elts);
169   } else {
170     Value *Elts[] = {
171       GetTagConstant(C, Tag),
172       Context,
173       NS,
174       ConstantInt::get(Type::getInt32Ty(C), Line),
175       MDString::get(C, Name)
176     };
177     R = MDNode::get(C, Elts);
178   }
179   DIImportedEntity M(R);
180   assert(M.Verify() && "Imported module should be valid");
181   AllImportedModules.push_back(TrackingVH<MDNode>(M));
182   return M;
183 }
184 
185 DIImportedEntity DIBuilder::createImportedModule(DIScope Context,
186                                                  DINameSpace NS,
187                                                  unsigned Line) {
188   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
189                                 Context, NS, Line, StringRef(), AllImportedModules);
190 }
191 
192 DIImportedEntity DIBuilder::createImportedModule(DIScope Context,
193                                                  DIImportedEntity NS,
194                                                  unsigned Line) {
195   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
196                                 Context, NS, Line, StringRef(), AllImportedModules);
197 }
198 
199 DIImportedEntity DIBuilder::createImportedDeclaration(DIScope Context,
200                                                       DIScope Decl,
201                                                       unsigned Line, StringRef Name) {
202   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_declaration,
203                                 Context, Decl.getRef(), Line, Name,
204                                 AllImportedModules);
205 }
206 
207 DIImportedEntity DIBuilder::createImportedDeclaration(DIScope Context,
208                                                       DIImportedEntity Imp,
209                                                       unsigned Line, StringRef Name) {
210   return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_declaration,
211                                 Context, Imp, Line, Name, AllImportedModules);
212 }
213 
214 /// createFile - Create a file descriptor to hold debugging information
215 /// for a file.
216 DIFile DIBuilder::createFile(StringRef Filename, StringRef Directory) {
217   Value *Elts[] = {
218     GetTagConstant(VMContext, dwarf::DW_TAG_file_type),
219     createFilePathPair(VMContext, Filename, Directory)
220   };
221   return DIFile(MDNode::get(VMContext, Elts));
222 }
223 
224 /// createEnumerator - Create a single enumerator value.
225 DIEnumerator DIBuilder::createEnumerator(StringRef Name, int64_t Val) {
226   assert(!Name.empty() && "Unable to create enumerator without name");
227   Value *Elts[] = {
228     GetTagConstant(VMContext, dwarf::DW_TAG_enumerator),
229     MDString::get(VMContext, Name),
230     ConstantInt::get(Type::getInt64Ty(VMContext), Val)
231   };
232   return DIEnumerator(MDNode::get(VMContext, Elts));
233 }
234 
235 /// \brief Create a DWARF unspecified type.
236 DIBasicType DIBuilder::createUnspecifiedType(StringRef Name) {
237   assert(!Name.empty() && "Unable to create type without name");
238   // Unspecified types are encoded in DIBasicType format. Line number, filename,
239   // size, alignment, offset and flags are always empty here.
240   Value *Elts[] = {
241     GetTagConstant(VMContext, dwarf::DW_TAG_unspecified_type),
242     nullptr, // Filename
243     nullptr, // Unused
244     MDString::get(VMContext, Name),
245     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
246     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Size
247     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Align
248     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
249     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags;
250     ConstantInt::get(Type::getInt32Ty(VMContext), 0)  // Encoding
251   };
252   return DIBasicType(MDNode::get(VMContext, Elts));
253 }
254 
255 /// \brief Create C++11 nullptr type.
256 DIBasicType DIBuilder::createNullPtrType() {
257   return createUnspecifiedType("decltype(nullptr)");
258 }
259 
260 /// createBasicType - Create debugging information entry for a basic
261 /// type, e.g 'char'.
262 DIBasicType
263 DIBuilder::createBasicType(StringRef Name, uint64_t SizeInBits,
264                            uint64_t AlignInBits, unsigned Encoding) {
265   assert(!Name.empty() && "Unable to create type without name");
266   // Basic types are encoded in DIBasicType format. Line number, filename,
267   // offset and flags are always empty here.
268   Value *Elts[] = {
269     GetTagConstant(VMContext, dwarf::DW_TAG_base_type),
270     nullptr, // File/directory name
271     nullptr, // Unused
272     MDString::get(VMContext, Name),
273     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
274     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
275     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
276     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
277     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags;
278     ConstantInt::get(Type::getInt32Ty(VMContext), Encoding)
279   };
280   return DIBasicType(MDNode::get(VMContext, Elts));
281 }
282 
283 /// createQualifiedType - Create debugging information entry for a qualified
284 /// type, e.g. 'const int'.
285 DIDerivedType DIBuilder::createQualifiedType(unsigned Tag, DIType FromTy) {
286   // Qualified types are encoded in DIDerivedType format.
287   Value *Elts[] = {
288     GetTagConstant(VMContext, Tag),
289     nullptr, // Filename
290     nullptr, // Unused
291     MDString::get(VMContext, StringRef()), // Empty name.
292     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
293     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Size
294     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Align
295     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
296     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags
297     FromTy.getRef()
298   };
299   return DIDerivedType(MDNode::get(VMContext, Elts));
300 }
301 
302 /// createPointerType - Create debugging information entry for a pointer.
303 DIDerivedType
304 DIBuilder::createPointerType(DIType PointeeTy, uint64_t SizeInBits,
305                              uint64_t AlignInBits, StringRef Name) {
306   // Pointer types are encoded in DIDerivedType format.
307   Value *Elts[] = {
308     GetTagConstant(VMContext, dwarf::DW_TAG_pointer_type),
309     nullptr, // Filename
310     nullptr, // Unused
311     MDString::get(VMContext, Name),
312     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
313     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
314     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
315     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
316     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags
317     PointeeTy.getRef()
318   };
319   return DIDerivedType(MDNode::get(VMContext, Elts));
320 }
321 
322 DIDerivedType DIBuilder::createMemberPointerType(DIType PointeeTy,
323                                                  DIType Base) {
324   // Pointer types are encoded in DIDerivedType format.
325   Value *Elts[] = {
326     GetTagConstant(VMContext, dwarf::DW_TAG_ptr_to_member_type),
327     nullptr, // Filename
328     nullptr, // Unused
329     nullptr,
330     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
331     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Size
332     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Align
333     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
334     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags
335     PointeeTy.getRef(),
336     Base.getRef()
337   };
338   return DIDerivedType(MDNode::get(VMContext, Elts));
339 }
340 
341 /// createReferenceType - Create debugging information entry for a reference
342 /// type.
343 DIDerivedType DIBuilder::createReferenceType(unsigned Tag, DIType RTy) {
344   assert(RTy.isType() && "Unable to create reference type");
345   // References are encoded in DIDerivedType format.
346   Value *Elts[] = {
347     GetTagConstant(VMContext, Tag),
348     nullptr, // Filename
349     nullptr, // TheCU,
350     nullptr, // Name
351     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
352     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Size
353     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Align
354     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
355     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags
356     RTy.getRef()
357   };
358   return DIDerivedType(MDNode::get(VMContext, Elts));
359 }
360 
361 /// createTypedef - Create debugging information entry for a typedef.
362 DIDerivedType DIBuilder::createTypedef(DIType Ty, StringRef Name, DIFile File,
363                                        unsigned LineNo, DIDescriptor Context) {
364   // typedefs are encoded in DIDerivedType format.
365   Value *Elts[] = {
366     GetTagConstant(VMContext, dwarf::DW_TAG_typedef),
367     File.getFileNode(),
368     DIScope(getNonCompileUnitScope(Context)).getRef(),
369     MDString::get(VMContext, Name),
370     ConstantInt::get(Type::getInt32Ty(VMContext), LineNo),
371     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Size
372     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Align
373     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
374     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags
375     Ty.getRef()
376   };
377   return DIDerivedType(MDNode::get(VMContext, Elts));
378 }
379 
380 /// createFriend - Create debugging information entry for a 'friend'.
381 DIDerivedType DIBuilder::createFriend(DIType Ty, DIType FriendTy) {
382   // typedefs are encoded in DIDerivedType format.
383   assert(Ty.isType() && "Invalid type!");
384   assert(FriendTy.isType() && "Invalid friend type!");
385   Value *Elts[] = {
386     GetTagConstant(VMContext, dwarf::DW_TAG_friend),
387     nullptr,
388     Ty.getRef(),
389     nullptr, // Name
390     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
391     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Size
392     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Align
393     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
394     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags
395     FriendTy.getRef()
396   };
397   return DIDerivedType(MDNode::get(VMContext, Elts));
398 }
399 
400 /// createInheritance - Create debugging information entry to establish
401 /// inheritance relationship between two types.
402 DIDerivedType DIBuilder::createInheritance(DIType Ty, DIType BaseTy,
403                                            uint64_t BaseOffset,
404                                            unsigned Flags) {
405   assert(Ty.isType() && "Unable to create inheritance");
406   // TAG_inheritance is encoded in DIDerivedType format.
407   Value *Elts[] = {
408     GetTagConstant(VMContext, dwarf::DW_TAG_inheritance),
409     nullptr,
410     Ty.getRef(),
411     nullptr, // Name
412     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
413     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Size
414     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Align
415     ConstantInt::get(Type::getInt64Ty(VMContext), BaseOffset),
416     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
417     BaseTy.getRef()
418   };
419   return DIDerivedType(MDNode::get(VMContext, Elts));
420 }
421 
422 /// createMemberType - Create debugging information entry for a member.
423 DIDerivedType DIBuilder::createMemberType(DIDescriptor Scope, StringRef Name,
424                                           DIFile File, unsigned LineNumber,
425                                           uint64_t SizeInBits,
426                                           uint64_t AlignInBits,
427                                           uint64_t OffsetInBits, unsigned Flags,
428                                           DIType Ty) {
429   // TAG_member is encoded in DIDerivedType format.
430   Value *Elts[] = {
431     GetTagConstant(VMContext, dwarf::DW_TAG_member),
432     File.getFileNode(),
433     DIScope(getNonCompileUnitScope(Scope)).getRef(),
434     MDString::get(VMContext, Name),
435     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
436     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
437     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
438     ConstantInt::get(Type::getInt64Ty(VMContext), OffsetInBits),
439     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
440     Ty.getRef()
441   };
442   return DIDerivedType(MDNode::get(VMContext, Elts));
443 }
444 
445 /// createStaticMemberType - Create debugging information entry for a
446 /// C++ static data member.
447 DIDerivedType
448 DIBuilder::createStaticMemberType(DIDescriptor Scope, StringRef Name,
449                                   DIFile File, unsigned LineNumber,
450                                   DIType Ty, unsigned Flags,
451                                   llvm::Value *Val) {
452   // TAG_member is encoded in DIDerivedType format.
453   Flags |= DIDescriptor::FlagStaticMember;
454   Value *Elts[] = {
455     GetTagConstant(VMContext, dwarf::DW_TAG_member),
456     File.getFileNode(),
457     DIScope(getNonCompileUnitScope(Scope)).getRef(),
458     MDString::get(VMContext, Name),
459     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
460     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Size
461     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Align
462     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
463     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
464     Ty.getRef(),
465     Val
466   };
467   return DIDerivedType(MDNode::get(VMContext, Elts));
468 }
469 
470 /// createObjCIVar - Create debugging information entry for Objective-C
471 /// instance variable.
472 DIDerivedType
473 DIBuilder::createObjCIVar(StringRef Name, DIFile File, unsigned LineNumber,
474                           uint64_t SizeInBits, uint64_t AlignInBits,
475                           uint64_t OffsetInBits, unsigned Flags, DIType Ty,
476                           StringRef PropertyName, StringRef GetterName,
477                           StringRef SetterName, unsigned PropertyAttributes) {
478   // TAG_member is encoded in DIDerivedType format.
479   Value *Elts[] = {
480     GetTagConstant(VMContext, dwarf::DW_TAG_member),
481     File.getFileNode(),
482     getNonCompileUnitScope(File),
483     MDString::get(VMContext, Name),
484     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
485     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
486     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
487     ConstantInt::get(Type::getInt64Ty(VMContext), OffsetInBits),
488     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
489     Ty,
490     MDString::get(VMContext, PropertyName),
491     MDString::get(VMContext, GetterName),
492     MDString::get(VMContext, SetterName),
493     ConstantInt::get(Type::getInt32Ty(VMContext), PropertyAttributes)
494   };
495   return DIDerivedType(MDNode::get(VMContext, Elts));
496 }
497 
498 /// createObjCIVar - Create debugging information entry for Objective-C
499 /// instance variable.
500 DIDerivedType DIBuilder::createObjCIVar(StringRef Name, DIFile File,
501                                         unsigned LineNumber,
502                                         uint64_t SizeInBits,
503                                         uint64_t AlignInBits,
504                                         uint64_t OffsetInBits, unsigned Flags,
505                                         DIType Ty, MDNode *PropertyNode) {
506   // TAG_member is encoded in DIDerivedType format.
507   Value *Elts[] = {
508     GetTagConstant(VMContext, dwarf::DW_TAG_member),
509     File.getFileNode(),
510     getNonCompileUnitScope(File),
511     MDString::get(VMContext, Name),
512     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
513     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
514     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
515     ConstantInt::get(Type::getInt64Ty(VMContext), OffsetInBits),
516     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
517     Ty,
518     PropertyNode
519   };
520   return DIDerivedType(MDNode::get(VMContext, Elts));
521 }
522 
523 /// createObjCProperty - Create debugging information entry for Objective-C
524 /// property.
525 DIObjCProperty
526 DIBuilder::createObjCProperty(StringRef Name, DIFile File, unsigned LineNumber,
527                               StringRef GetterName, StringRef SetterName,
528                               unsigned PropertyAttributes, DIType Ty) {
529   Value *Elts[] = {
530     GetTagConstant(VMContext, dwarf::DW_TAG_APPLE_property),
531     MDString::get(VMContext, Name),
532     File,
533     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
534     MDString::get(VMContext, GetterName),
535     MDString::get(VMContext, SetterName),
536     ConstantInt::get(Type::getInt32Ty(VMContext), PropertyAttributes),
537     Ty
538   };
539   return DIObjCProperty(MDNode::get(VMContext, Elts));
540 }
541 
542 /// createTemplateTypeParameter - Create debugging information for template
543 /// type parameter.
544 DITemplateTypeParameter
545 DIBuilder::createTemplateTypeParameter(DIDescriptor Context, StringRef Name,
546                                        DIType Ty, MDNode *File, unsigned LineNo,
547                                        unsigned ColumnNo) {
548   Value *Elts[] = {
549     GetTagConstant(VMContext, dwarf::DW_TAG_template_type_parameter),
550     DIScope(getNonCompileUnitScope(Context)).getRef(),
551     MDString::get(VMContext, Name),
552     Ty.getRef(),
553     File,
554     ConstantInt::get(Type::getInt32Ty(VMContext), LineNo),
555     ConstantInt::get(Type::getInt32Ty(VMContext), ColumnNo)
556   };
557   return DITemplateTypeParameter(MDNode::get(VMContext, Elts));
558 }
559 
560 DITemplateValueParameter
561 DIBuilder::createTemplateValueParameter(unsigned Tag, DIDescriptor Context,
562                                         StringRef Name, DIType Ty,
563                                         Value *Val, MDNode *File,
564                                         unsigned LineNo,
565                                         unsigned ColumnNo) {
566   Value *Elts[] = {
567     GetTagConstant(VMContext, Tag),
568     DIScope(getNonCompileUnitScope(Context)).getRef(),
569     MDString::get(VMContext, Name),
570     Ty.getRef(),
571     Val,
572     File,
573     ConstantInt::get(Type::getInt32Ty(VMContext), LineNo),
574     ConstantInt::get(Type::getInt32Ty(VMContext), ColumnNo)
575   };
576   return DITemplateValueParameter(MDNode::get(VMContext, Elts));
577 }
578 
579 /// createTemplateValueParameter - Create debugging information for template
580 /// value parameter.
581 DITemplateValueParameter
582 DIBuilder::createTemplateValueParameter(DIDescriptor Context, StringRef Name,
583                                         DIType Ty, Value *Val,
584                                         MDNode *File, unsigned LineNo,
585                                         unsigned ColumnNo) {
586   return createTemplateValueParameter(dwarf::DW_TAG_template_value_parameter,
587                                       Context, Name, Ty, Val, File, LineNo,
588                                       ColumnNo);
589 }
590 
591 DITemplateValueParameter
592 DIBuilder::createTemplateTemplateParameter(DIDescriptor Context, StringRef Name,
593                                            DIType Ty, StringRef Val,
594                                            MDNode *File, unsigned LineNo,
595                                            unsigned ColumnNo) {
596   return createTemplateValueParameter(
597       dwarf::DW_TAG_GNU_template_template_param, Context, Name, Ty,
598       MDString::get(VMContext, Val), File, LineNo, ColumnNo);
599 }
600 
601 DITemplateValueParameter
602 DIBuilder::createTemplateParameterPack(DIDescriptor Context, StringRef Name,
603                                        DIType Ty, DIArray Val,
604                                        MDNode *File, unsigned LineNo,
605                                        unsigned ColumnNo) {
606   return createTemplateValueParameter(dwarf::DW_TAG_GNU_template_parameter_pack,
607                                       Context, Name, Ty, Val, File, LineNo,
608                                       ColumnNo);
609 }
610 
611 /// createClassType - Create debugging information entry for a class.
612 DICompositeType DIBuilder::createClassType(DIDescriptor Context, StringRef Name,
613                                            DIFile File, unsigned LineNumber,
614                                            uint64_t SizeInBits,
615                                            uint64_t AlignInBits,
616                                            uint64_t OffsetInBits,
617                                            unsigned Flags, DIType DerivedFrom,
618                                            DIArray Elements,
619                                            DIType VTableHolder,
620                                            MDNode *TemplateParams,
621                                            StringRef UniqueIdentifier) {
622   assert((!Context || Context.isScope() || Context.isType()) &&
623          "createClassType should be called with a valid Context");
624   // TAG_class_type is encoded in DICompositeType format.
625   Value *Elts[] = {
626     GetTagConstant(VMContext, dwarf::DW_TAG_class_type),
627     File.getFileNode(),
628     DIScope(getNonCompileUnitScope(Context)).getRef(),
629     MDString::get(VMContext, Name),
630     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
631     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
632     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
633     ConstantInt::get(Type::getInt32Ty(VMContext), OffsetInBits),
634     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
635     DerivedFrom.getRef(),
636     Elements,
637     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
638     VTableHolder.getRef(),
639     TemplateParams,
640     UniqueIdentifier.empty() ? nullptr
641                              : MDString::get(VMContext, UniqueIdentifier)
642   };
643   DICompositeType R(MDNode::get(VMContext, Elts));
644   assert(R.isCompositeType() &&
645          "createClassType should return a DICompositeType");
646   if (!UniqueIdentifier.empty())
647     retainType(R);
648   return R;
649 }
650 
651 /// createStructType - Create debugging information entry for a struct.
652 DICompositeType DIBuilder::createStructType(DIDescriptor Context,
653                                             StringRef Name, DIFile File,
654                                             unsigned LineNumber,
655                                             uint64_t SizeInBits,
656                                             uint64_t AlignInBits,
657                                             unsigned Flags, DIType DerivedFrom,
658                                             DIArray Elements,
659                                             unsigned RunTimeLang,
660                                             DIType VTableHolder,
661                                             StringRef UniqueIdentifier) {
662  // TAG_structure_type is encoded in DICompositeType format.
663   Value *Elts[] = {
664     GetTagConstant(VMContext, dwarf::DW_TAG_structure_type),
665     File.getFileNode(),
666     DIScope(getNonCompileUnitScope(Context)).getRef(),
667     MDString::get(VMContext, Name),
668     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
669     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
670     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
671     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
672     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
673     DerivedFrom.getRef(),
674     Elements,
675     ConstantInt::get(Type::getInt32Ty(VMContext), RunTimeLang),
676     VTableHolder.getRef(),
677     nullptr,
678     UniqueIdentifier.empty() ? nullptr
679                              : MDString::get(VMContext, UniqueIdentifier)
680   };
681   DICompositeType R(MDNode::get(VMContext, Elts));
682   assert(R.isCompositeType() &&
683          "createStructType should return a DICompositeType");
684   if (!UniqueIdentifier.empty())
685     retainType(R);
686   return R;
687 }
688 
689 /// createUnionType - Create debugging information entry for an union.
690 DICompositeType DIBuilder::createUnionType(DIDescriptor Scope, StringRef Name,
691                                            DIFile File, unsigned LineNumber,
692                                            uint64_t SizeInBits,
693                                            uint64_t AlignInBits, unsigned Flags,
694                                            DIArray Elements,
695                                            unsigned RunTimeLang,
696                                            StringRef UniqueIdentifier) {
697   // TAG_union_type is encoded in DICompositeType format.
698   Value *Elts[] = {
699     GetTagConstant(VMContext, dwarf::DW_TAG_union_type),
700     File.getFileNode(),
701     DIScope(getNonCompileUnitScope(Scope)).getRef(),
702     MDString::get(VMContext, Name),
703     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
704     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
705     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
706     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
707     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
708     nullptr,
709     Elements,
710     ConstantInt::get(Type::getInt32Ty(VMContext), RunTimeLang),
711     nullptr,
712     nullptr,
713     UniqueIdentifier.empty() ? nullptr
714                              : MDString::get(VMContext, UniqueIdentifier)
715   };
716   DICompositeType R(MDNode::get(VMContext, Elts));
717   if (!UniqueIdentifier.empty())
718     retainType(R);
719   return R;
720 }
721 
722 /// createSubroutineType - Create subroutine type.
723 DISubroutineType DIBuilder::createSubroutineType(DIFile File,
724                                                  DITypeArray ParameterTypes,
725                                                  unsigned Flags) {
726   // TAG_subroutine_type is encoded in DICompositeType format.
727   Value *Elts[] = {
728     GetTagConstant(VMContext, dwarf::DW_TAG_subroutine_type),
729     Constant::getNullValue(Type::getInt32Ty(VMContext)),
730     nullptr,
731     MDString::get(VMContext, ""),
732     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
733     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Size
734     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Align
735     ConstantInt::get(Type::getInt64Ty(VMContext), 0), // Offset
736     ConstantInt::get(Type::getInt32Ty(VMContext), Flags), // Flags
737     nullptr,
738     ParameterTypes,
739     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
740     nullptr,
741     nullptr,
742     nullptr  // Type Identifer
743   };
744   return DISubroutineType(MDNode::get(VMContext, Elts));
745 }
746 
747 /// createEnumerationType - Create debugging information entry for an
748 /// enumeration.
749 DICompositeType DIBuilder::createEnumerationType(
750     DIDescriptor Scope, StringRef Name, DIFile File, unsigned LineNumber,
751     uint64_t SizeInBits, uint64_t AlignInBits, DIArray Elements,
752     DIType UnderlyingType, StringRef UniqueIdentifier) {
753   // TAG_enumeration_type is encoded in DICompositeType format.
754   Value *Elts[] = {
755     GetTagConstant(VMContext, dwarf::DW_TAG_enumeration_type),
756     File.getFileNode(),
757     DIScope(getNonCompileUnitScope(Scope)).getRef(),
758     MDString::get(VMContext, Name),
759     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
760     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
761     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
762     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Offset
763     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags
764     UnderlyingType.getRef(),
765     Elements,
766     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
767     nullptr,
768     nullptr,
769     UniqueIdentifier.empty() ? nullptr
770                              : MDString::get(VMContext, UniqueIdentifier)
771   };
772   DICompositeType CTy(MDNode::get(VMContext, Elts));
773   AllEnumTypes.push_back(CTy);
774   if (!UniqueIdentifier.empty())
775     retainType(CTy);
776   return CTy;
777 }
778 
779 /// createArrayType - Create debugging information entry for an array.
780 DICompositeType DIBuilder::createArrayType(uint64_t Size, uint64_t AlignInBits,
781                                            DIType Ty, DIArray Subscripts) {
782   // TAG_array_type is encoded in DICompositeType format.
783   Value *Elts[] = {
784     GetTagConstant(VMContext, dwarf::DW_TAG_array_type),
785     nullptr, // Filename/Directory,
786     nullptr, // Unused
787     MDString::get(VMContext, ""),
788     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
789     ConstantInt::get(Type::getInt64Ty(VMContext), Size),
790     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
791     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Offset
792     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Flags
793     Ty.getRef(),
794     Subscripts,
795     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
796     nullptr,
797     nullptr,
798     nullptr  // Type Identifer
799   };
800   return DICompositeType(MDNode::get(VMContext, Elts));
801 }
802 
803 /// createVectorType - Create debugging information entry for a vector.
804 DICompositeType DIBuilder::createVectorType(uint64_t Size, uint64_t AlignInBits,
805                                             DIType Ty, DIArray Subscripts) {
806   // A vector is an array type with the FlagVector flag applied.
807   Value *Elts[] = {
808     GetTagConstant(VMContext, dwarf::DW_TAG_array_type),
809     nullptr, // Filename/Directory,
810     nullptr, // Unused
811     MDString::get(VMContext, ""),
812     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
813     ConstantInt::get(Type::getInt64Ty(VMContext), Size),
814     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
815     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Offset
816     ConstantInt::get(Type::getInt32Ty(VMContext), DIType::FlagVector),
817     Ty.getRef(),
818     Subscripts,
819     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
820     nullptr,
821     nullptr,
822     nullptr  // Type Identifer
823   };
824   return DICompositeType(MDNode::get(VMContext, Elts));
825 }
826 
827 /// createArtificialType - Create a new DIType with "artificial" flag set.
828 DIType DIBuilder::createArtificialType(DIType Ty) {
829   if (Ty.isArtificial())
830     return Ty;
831 
832   SmallVector<Value *, 9> Elts;
833   MDNode *N = Ty;
834   assert (N && "Unexpected input DIType!");
835   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
836     Elts.push_back(N->getOperand(i));
837 
838   unsigned CurFlags = Ty.getFlags();
839   CurFlags = CurFlags | DIType::FlagArtificial;
840 
841   // Flags are stored at this slot.
842   // FIXME: Add an enum for this magic value.
843   Elts[8] =  ConstantInt::get(Type::getInt32Ty(VMContext), CurFlags);
844 
845   return DIType(MDNode::get(VMContext, Elts));
846 }
847 
848 /// createObjectPointerType - Create a new type with both the object pointer
849 /// and artificial flags set.
850 DIType DIBuilder::createObjectPointerType(DIType Ty) {
851   if (Ty.isObjectPointer())
852     return Ty;
853 
854   SmallVector<Value *, 9> Elts;
855   MDNode *N = Ty;
856   assert (N && "Unexpected input DIType!");
857   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
858     Elts.push_back(N->getOperand(i));
859 
860   unsigned CurFlags = Ty.getFlags();
861   CurFlags = CurFlags | (DIType::FlagObjectPointer | DIType::FlagArtificial);
862 
863   // Flags are stored at this slot.
864   // FIXME: Add an enum for this magic value.
865   Elts[8] = ConstantInt::get(Type::getInt32Ty(VMContext), CurFlags);
866 
867   return DIType(MDNode::get(VMContext, Elts));
868 }
869 
870 /// retainType - Retain DIType in a module even if it is not referenced
871 /// through debug info anchors.
872 void DIBuilder::retainType(DIType T) {
873   AllRetainTypes.push_back(TrackingVH<MDNode>(T));
874 }
875 
876 /// createUnspecifiedParameter - Create unspeicified type descriptor
877 /// for the subroutine type.
878 DIBasicType DIBuilder::createUnspecifiedParameter() {
879   return DIBasicType();
880 }
881 
882 /// createForwardDecl - Create a temporary forward-declared type that
883 /// can be RAUW'd if the full type is seen.
884 DICompositeType
885 DIBuilder::createForwardDecl(unsigned Tag, StringRef Name, DIDescriptor Scope,
886                              DIFile F, unsigned Line, unsigned RuntimeLang,
887                              uint64_t SizeInBits, uint64_t AlignInBits,
888                              StringRef UniqueIdentifier) {
889   // Create a temporary MDNode.
890   Value *Elts[] = {
891     GetTagConstant(VMContext, Tag),
892     F.getFileNode(),
893     DIScope(getNonCompileUnitScope(Scope)).getRef(),
894     MDString::get(VMContext, Name),
895     ConstantInt::get(Type::getInt32Ty(VMContext), Line),
896     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
897     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
898     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Offset
899     ConstantInt::get(Type::getInt32Ty(VMContext), DIDescriptor::FlagFwdDecl),
900     nullptr,
901     DIArray(),
902     ConstantInt::get(Type::getInt32Ty(VMContext), RuntimeLang),
903     nullptr,
904     nullptr, //TemplateParams
905     UniqueIdentifier.empty() ? nullptr
906                              : MDString::get(VMContext, UniqueIdentifier)
907   };
908   MDNode *Node = MDNode::get(VMContext, Elts);
909   DICompositeType RetTy(Node);
910   assert(RetTy.isCompositeType() &&
911          "createForwardDecl result should be a DIType");
912   if (!UniqueIdentifier.empty())
913     retainType(RetTy);
914   return RetTy;
915 }
916 
917 /// createForwardDecl - Create a temporary forward-declared type that
918 /// can be RAUW'd if the full type is seen.
919 DICompositeType DIBuilder::createReplaceableForwardDecl(
920     unsigned Tag, StringRef Name, DIDescriptor Scope, DIFile F, unsigned Line,
921     unsigned RuntimeLang, uint64_t SizeInBits, uint64_t AlignInBits,
922     StringRef UniqueIdentifier) {
923   // Create a temporary MDNode.
924   Value *Elts[] = {
925     GetTagConstant(VMContext, Tag),
926     F.getFileNode(),
927     DIScope(getNonCompileUnitScope(Scope)).getRef(),
928     MDString::get(VMContext, Name),
929     ConstantInt::get(Type::getInt32Ty(VMContext), Line),
930     ConstantInt::get(Type::getInt64Ty(VMContext), SizeInBits),
931     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
932     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Offset
933     ConstantInt::get(Type::getInt32Ty(VMContext), DIDescriptor::FlagFwdDecl),
934     nullptr,
935     DIArray(),
936     ConstantInt::get(Type::getInt32Ty(VMContext), RuntimeLang),
937     nullptr,
938     nullptr, //TemplateParams
939     UniqueIdentifier.empty() ? nullptr
940                              : MDString::get(VMContext, UniqueIdentifier)
941   };
942   MDNode *Node = MDNode::getTemporary(VMContext, Elts);
943   DICompositeType RetTy(Node);
944   assert(RetTy.isCompositeType() &&
945          "createForwardDecl result should be a DIType");
946   if (!UniqueIdentifier.empty())
947     retainType(RetTy);
948   return RetTy;
949 }
950 
951 /// getOrCreateArray - Get a DIArray, create one if required.
952 DIArray DIBuilder::getOrCreateArray(ArrayRef<Value *> Elements) {
953   return DIArray(MDNode::get(VMContext, Elements));
954 }
955 
956 /// getOrCreateTypeArray - Get a DITypeArray, create one if required.
957 DITypeArray DIBuilder::getOrCreateTypeArray(ArrayRef<Value *> Elements) {
958   SmallVector<llvm::Value *, 16> Elts;
959   for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
960     if (Elements[i] && isa<MDNode>(Elements[i]))
961       Elts.push_back(DIType(cast<MDNode>(Elements[i])).getRef());
962     else
963       Elts.push_back(Elements[i]);
964   }
965   return DITypeArray(MDNode::get(VMContext, Elts));
966 }
967 
968 /// getOrCreateSubrange - Create a descriptor for a value range.  This
969 /// implicitly uniques the values returned.
970 DISubrange DIBuilder::getOrCreateSubrange(int64_t Lo, int64_t Count) {
971   Value *Elts[] = {
972     GetTagConstant(VMContext, dwarf::DW_TAG_subrange_type),
973     ConstantInt::get(Type::getInt64Ty(VMContext), Lo),
974     ConstantInt::get(Type::getInt64Ty(VMContext), Count)
975   };
976 
977   return DISubrange(MDNode::get(VMContext, Elts));
978 }
979 
980 /// \brief Create a new descriptor for the specified global.
981 DIGlobalVariable DIBuilder::createGlobalVariable(StringRef Name,
982                                                  StringRef LinkageName,
983                                                  DIFile F, unsigned LineNumber,
984                                                  DITypeRef Ty, bool isLocalToUnit,
985                                                  Value *Val) {
986   Value *Elts[] = {
987     GetTagConstant(VMContext, dwarf::DW_TAG_variable),
988     Constant::getNullValue(Type::getInt32Ty(VMContext)),
989     nullptr, // TheCU,
990     MDString::get(VMContext, Name),
991     MDString::get(VMContext, Name),
992     MDString::get(VMContext, LinkageName),
993     F,
994     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
995     Ty,
996     ConstantInt::get(Type::getInt32Ty(VMContext), isLocalToUnit),
997     ConstantInt::get(Type::getInt32Ty(VMContext), 1), /* isDefinition*/
998     Val,
999     DIDescriptor()
1000   };
1001   MDNode *Node = MDNode::get(VMContext, Elts);
1002   AllGVs.push_back(Node);
1003   return DIGlobalVariable(Node);
1004 }
1005 
1006 /// \brief Create a new descriptor for the specified global.
1007 DIGlobalVariable DIBuilder::createGlobalVariable(StringRef Name, DIFile F,
1008                                                  unsigned LineNumber,
1009                                                  DITypeRef Ty,
1010                                                  bool isLocalToUnit,
1011                                                  Value *Val) {
1012   return createGlobalVariable(Name, Name, F, LineNumber, Ty, isLocalToUnit,
1013                               Val);
1014 }
1015 
1016 /// createStaticVariable - Create a new descriptor for the specified static
1017 /// variable.
1018 DIGlobalVariable DIBuilder::createStaticVariable(DIDescriptor Context,
1019                                                  StringRef Name,
1020                                                  StringRef LinkageName,
1021                                                  DIFile F, unsigned LineNumber,
1022                                                  DITypeRef Ty,
1023                                                  bool isLocalToUnit,
1024                                                  Value *Val, MDNode *Decl) {
1025   Value *Elts[] = {
1026     GetTagConstant(VMContext, dwarf::DW_TAG_variable),
1027     Constant::getNullValue(Type::getInt32Ty(VMContext)),
1028     getNonCompileUnitScope(Context),
1029     MDString::get(VMContext, Name),
1030     MDString::get(VMContext, Name),
1031     MDString::get(VMContext, LinkageName),
1032     F,
1033     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
1034     Ty,
1035     ConstantInt::get(Type::getInt32Ty(VMContext), isLocalToUnit),
1036     ConstantInt::get(Type::getInt32Ty(VMContext), 1), /* isDefinition*/
1037     Val,
1038     DIDescriptor(Decl)
1039   };
1040   MDNode *Node = MDNode::get(VMContext, Elts);
1041   AllGVs.push_back(Node);
1042   return DIGlobalVariable(Node);
1043 }
1044 
1045 /// createVariable - Create a new descriptor for the specified variable.
1046 DIVariable DIBuilder::createLocalVariable(unsigned Tag, DIDescriptor Scope,
1047                                           StringRef Name, DIFile File,
1048                                           unsigned LineNo, DITypeRef Ty,
1049                                           bool AlwaysPreserve, unsigned Flags,
1050                                           unsigned ArgNo) {
1051   DIDescriptor Context(getNonCompileUnitScope(Scope));
1052   assert((!Context || Context.isScope()) &&
1053          "createLocalVariable should be called with a valid Context");
1054   Value *Elts[] = {
1055     GetTagConstant(VMContext, Tag),
1056     getNonCompileUnitScope(Scope),
1057     MDString::get(VMContext, Name),
1058     File,
1059     ConstantInt::get(Type::getInt32Ty(VMContext), (LineNo | (ArgNo << 24))),
1060     Ty,
1061     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
1062     Constant::getNullValue(Type::getInt32Ty(VMContext))
1063   };
1064   MDNode *Node = MDNode::get(VMContext, Elts);
1065   if (AlwaysPreserve) {
1066     // The optimizer may remove local variable. If there is an interest
1067     // to preserve variable info in such situation then stash it in a
1068     // named mdnode.
1069     DISubprogram Fn(getDISubprogram(Scope));
1070     NamedMDNode *FnLocals = getOrInsertFnSpecificMDNode(M, Fn);
1071     FnLocals->addOperand(Node);
1072   }
1073   DIVariable RetVar(Node);
1074   assert(RetVar.isVariable() &&
1075          "createLocalVariable should return a valid DIVariable");
1076   return RetVar;
1077 }
1078 
1079 /// createComplexVariable - Create a new descriptor for the specified variable
1080 /// which has a complex address expression for its address.
1081 DIVariable DIBuilder::createComplexVariable(unsigned Tag, DIDescriptor Scope,
1082                                             StringRef Name, DIFile F,
1083                                             unsigned LineNo,
1084                                             DITypeRef Ty,
1085                                             ArrayRef<Value *> Addr,
1086                                             unsigned ArgNo) {
1087   assert(Addr.size() > 0 && "complex address is empty");
1088   Value *Elts[] = {
1089     GetTagConstant(VMContext, Tag),
1090     getNonCompileUnitScope(Scope),
1091     MDString::get(VMContext, Name),
1092     F,
1093     ConstantInt::get(Type::getInt32Ty(VMContext),
1094                      (LineNo | (ArgNo << 24))),
1095     Ty,
1096     Constant::getNullValue(Type::getInt32Ty(VMContext)),
1097     Constant::getNullValue(Type::getInt32Ty(VMContext)),
1098     MDNode::get(VMContext, Addr)
1099   };
1100   return DIVariable(MDNode::get(VMContext, Elts));
1101 }
1102 
1103 /// createVariablePiece - Create a descriptor to describe one part
1104 /// of aggregate variable that is fragmented across multiple Values.
1105 DIVariable DIBuilder::createVariablePiece(DIVariable Variable,
1106                                           unsigned OffsetInBytes,
1107                                           unsigned SizeInBytes) {
1108   assert(SizeInBytes > 0 && "zero-size piece");
1109   Value *Addr[] = {
1110     ConstantInt::get(Type::getInt32Ty(VMContext), OpPiece),
1111     ConstantInt::get(Type::getInt32Ty(VMContext), OffsetInBytes),
1112     ConstantInt::get(Type::getInt32Ty(VMContext), SizeInBytes)
1113   };
1114 
1115   assert((Variable->getNumOperands() == 8 || Variable.isVariablePiece()) &&
1116          "variable already has a complex address");
1117   SmallVector<Value *, 9> Elts;
1118   for (unsigned i = 0; i < 8; ++i)
1119     Elts.push_back(Variable->getOperand(i));
1120 
1121   Elts.push_back(MDNode::get(VMContext, Addr));
1122   return DIVariable(MDNode::get(VMContext, Elts));
1123 }
1124 
1125 /// createFunction - Create a new descriptor for the specified function.
1126 /// FIXME: this is added for dragonegg. Once we update dragonegg
1127 /// to call resolve function, this will be removed.
1128 DISubprogram DIBuilder::createFunction(DIScopeRef Context, StringRef Name,
1129                                        StringRef LinkageName, DIFile File,
1130                                        unsigned LineNo, DICompositeType Ty,
1131                                        bool isLocalToUnit, bool isDefinition,
1132                                        unsigned ScopeLine, unsigned Flags,
1133                                        bool isOptimized, Function *Fn,
1134                                        MDNode *TParams, MDNode *Decl) {
1135   // dragonegg does not generate identifier for types, so using an empty map
1136   // to resolve the context should be fine.
1137   DITypeIdentifierMap EmptyMap;
1138   return createFunction(Context.resolve(EmptyMap), Name, LinkageName, File,
1139                         LineNo, Ty, isLocalToUnit, isDefinition, ScopeLine,
1140                         Flags, isOptimized, Fn, TParams, Decl);
1141 }
1142 
1143 /// createFunction - Create a new descriptor for the specified function.
1144 DISubprogram DIBuilder::createFunction(DIDescriptor Context, StringRef Name,
1145                                        StringRef LinkageName, DIFile File,
1146                                        unsigned LineNo, DICompositeType Ty,
1147                                        bool isLocalToUnit, bool isDefinition,
1148                                        unsigned ScopeLine, unsigned Flags,
1149                                        bool isOptimized, Function *Fn,
1150                                        MDNode *TParams, MDNode *Decl) {
1151   assert(Ty.getTag() == dwarf::DW_TAG_subroutine_type &&
1152          "function types should be subroutines");
1153   Value *TElts[] = { GetTagConstant(VMContext, DW_TAG_base_type) };
1154   Value *Elts[] = {
1155     GetTagConstant(VMContext, dwarf::DW_TAG_subprogram),
1156     File.getFileNode(),
1157     DIScope(getNonCompileUnitScope(Context)).getRef(),
1158     MDString::get(VMContext, Name),
1159     MDString::get(VMContext, Name),
1160     MDString::get(VMContext, LinkageName),
1161     ConstantInt::get(Type::getInt32Ty(VMContext), LineNo),
1162     Ty,
1163     ConstantInt::get(Type::getInt1Ty(VMContext), isLocalToUnit),
1164     ConstantInt::get(Type::getInt1Ty(VMContext), isDefinition),
1165     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
1166     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
1167     nullptr,
1168     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
1169     ConstantInt::get(Type::getInt1Ty(VMContext), isOptimized),
1170     Fn,
1171     TParams,
1172     Decl,
1173     MDNode::getTemporary(VMContext, TElts),
1174     ConstantInt::get(Type::getInt32Ty(VMContext), ScopeLine)
1175   };
1176   MDNode *Node = MDNode::get(VMContext, Elts);
1177 
1178   // Create a named metadata so that we do not lose this mdnode.
1179   if (isDefinition)
1180     AllSubprograms.push_back(Node);
1181   DISubprogram S(Node);
1182   assert(S.isSubprogram() &&
1183          "createFunction should return a valid DISubprogram");
1184   return S;
1185 }
1186 
1187 /// createMethod - Create a new descriptor for the specified C++ method.
1188 DISubprogram DIBuilder::createMethod(DIDescriptor Context, StringRef Name,
1189                                      StringRef LinkageName, DIFile F,
1190                                      unsigned LineNo, DICompositeType Ty,
1191                                      bool isLocalToUnit, bool isDefinition,
1192                                      unsigned VK, unsigned VIndex,
1193                                      DIType VTableHolder, unsigned Flags,
1194                                      bool isOptimized, Function *Fn,
1195                                      MDNode *TParam) {
1196   assert(Ty.getTag() == dwarf::DW_TAG_subroutine_type &&
1197          "function types should be subroutines");
1198   assert(getNonCompileUnitScope(Context) &&
1199          "Methods should have both a Context and a context that isn't "
1200          "the compile unit.");
1201   Value *Elts[] = {
1202     GetTagConstant(VMContext, dwarf::DW_TAG_subprogram),
1203     F.getFileNode(),
1204     DIScope(Context).getRef(),
1205     MDString::get(VMContext, Name),
1206     MDString::get(VMContext, Name),
1207     MDString::get(VMContext, LinkageName),
1208     ConstantInt::get(Type::getInt32Ty(VMContext), LineNo),
1209     Ty,
1210     ConstantInt::get(Type::getInt1Ty(VMContext), isLocalToUnit),
1211     ConstantInt::get(Type::getInt1Ty(VMContext), isDefinition),
1212     ConstantInt::get(Type::getInt32Ty(VMContext), VK),
1213     ConstantInt::get(Type::getInt32Ty(VMContext), VIndex),
1214     VTableHolder.getRef(),
1215     ConstantInt::get(Type::getInt32Ty(VMContext), Flags),
1216     ConstantInt::get(Type::getInt1Ty(VMContext), isOptimized),
1217     Fn,
1218     TParam,
1219     Constant::getNullValue(Type::getInt32Ty(VMContext)),
1220     nullptr,
1221     // FIXME: Do we want to use different scope/lines?
1222     ConstantInt::get(Type::getInt32Ty(VMContext), LineNo)
1223   };
1224   MDNode *Node = MDNode::get(VMContext, Elts);
1225   if (isDefinition)
1226     AllSubprograms.push_back(Node);
1227   DISubprogram S(Node);
1228   assert(S.isSubprogram() && "createMethod should return a valid DISubprogram");
1229   return S;
1230 }
1231 
1232 /// createNameSpace - This creates new descriptor for a namespace
1233 /// with the specified parent scope.
1234 DINameSpace DIBuilder::createNameSpace(DIDescriptor Scope, StringRef Name,
1235                                        DIFile File, unsigned LineNo) {
1236   Value *Elts[] = {
1237     GetTagConstant(VMContext, dwarf::DW_TAG_namespace),
1238     File.getFileNode(),
1239     getNonCompileUnitScope(Scope),
1240     MDString::get(VMContext, Name),
1241     ConstantInt::get(Type::getInt32Ty(VMContext), LineNo)
1242   };
1243   DINameSpace R(MDNode::get(VMContext, Elts));
1244   assert(R.Verify() &&
1245          "createNameSpace should return a verifiable DINameSpace");
1246   return R;
1247 }
1248 
1249 /// createLexicalBlockFile - This creates a new MDNode that encapsulates
1250 /// an existing scope with a new filename.
1251 DILexicalBlockFile DIBuilder::createLexicalBlockFile(DIDescriptor Scope,
1252                                                      DIFile File) {
1253   Value *Elts[] = {
1254     GetTagConstant(VMContext, dwarf::DW_TAG_lexical_block),
1255     File.getFileNode(),
1256     Scope
1257   };
1258   DILexicalBlockFile R(MDNode::get(VMContext, Elts));
1259   assert(
1260       R.Verify() &&
1261       "createLexicalBlockFile should return a verifiable DILexicalBlockFile");
1262   return R;
1263 }
1264 
1265 DILexicalBlock DIBuilder::createLexicalBlock(DIDescriptor Scope, DIFile File,
1266                                              unsigned Line, unsigned Col,
1267                                              unsigned Discriminator) {
1268   // FIXME: This isn't thread safe nor the right way to defeat MDNode uniquing.
1269   // I believe the right way is to have a self-referential element in the node.
1270   // Also: why do we bother with line/column - they're not used and the
1271   // documentation (SourceLevelDebugging.rst) claims the line/col are necessary
1272   // for uniquing, yet then we have this other solution (because line/col were
1273   // inadequate) anyway. Remove all 3 and replace them with a self-reference.
1274 
1275   // Defeat MDNode uniquing for lexical blocks by using unique id.
1276   static unsigned int unique_id = 0;
1277   Value *Elts[] = {
1278     GetTagConstant(VMContext, dwarf::DW_TAG_lexical_block),
1279     File.getFileNode(),
1280     getNonCompileUnitScope(Scope),
1281     ConstantInt::get(Type::getInt32Ty(VMContext), Line),
1282     ConstantInt::get(Type::getInt32Ty(VMContext), Col),
1283     ConstantInt::get(Type::getInt32Ty(VMContext), Discriminator),
1284     ConstantInt::get(Type::getInt32Ty(VMContext), unique_id++)
1285   };
1286   DILexicalBlock R(MDNode::get(VMContext, Elts));
1287   assert(R.Verify() &&
1288          "createLexicalBlock should return a verifiable DILexicalBlock");
1289   return R;
1290 }
1291 
1292 /// insertDeclare - Insert a new llvm.dbg.declare intrinsic call.
1293 Instruction *DIBuilder::insertDeclare(Value *Storage, DIVariable VarInfo,
1294                                       Instruction *InsertBefore) {
1295   assert(Storage && "no storage passed to dbg.declare");
1296   assert(VarInfo.isVariable() &&
1297          "empty or invalid DIVariable passed to dbg.declare");
1298   if (!DeclareFn)
1299     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
1300 
1301   Value *Args[] = { MDNode::get(Storage->getContext(), Storage), VarInfo };
1302   return CallInst::Create(DeclareFn, Args, "", InsertBefore);
1303 }
1304 
1305 /// insertDeclare - Insert a new llvm.dbg.declare intrinsic call.
1306 Instruction *DIBuilder::insertDeclare(Value *Storage, DIVariable VarInfo,
1307                                       BasicBlock *InsertAtEnd) {
1308   assert(Storage && "no storage passed to dbg.declare");
1309   assert(VarInfo.isVariable() &&
1310          "empty or invalid DIVariable passed to dbg.declare");
1311   if (!DeclareFn)
1312     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
1313 
1314   Value *Args[] = { MDNode::get(Storage->getContext(), Storage), VarInfo };
1315 
1316   // If this block already has a terminator then insert this intrinsic
1317   // before the terminator.
1318   if (TerminatorInst *T = InsertAtEnd->getTerminator())
1319     return CallInst::Create(DeclareFn, Args, "", T);
1320   else
1321     return CallInst::Create(DeclareFn, Args, "", InsertAtEnd);
1322 }
1323 
1324 /// insertDbgValueIntrinsic - Insert a new llvm.dbg.value intrinsic call.
1325 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
1326                                                 DIVariable VarInfo,
1327                                                 Instruction *InsertBefore) {
1328   assert(V && "no value passed to dbg.value");
1329   assert(VarInfo.isVariable() &&
1330          "empty or invalid DIVariable passed to dbg.value");
1331   if (!ValueFn)
1332     ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
1333 
1334   Value *Args[] = { MDNode::get(V->getContext(), V),
1335                     ConstantInt::get(Type::getInt64Ty(V->getContext()), Offset),
1336                     VarInfo };
1337   return CallInst::Create(ValueFn, Args, "", InsertBefore);
1338 }
1339 
1340 /// insertDbgValueIntrinsic - Insert a new llvm.dbg.value intrinsic call.
1341 Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
1342                                                 DIVariable VarInfo,
1343                                                 BasicBlock *InsertAtEnd) {
1344   assert(V && "no value passed to dbg.value");
1345   assert(VarInfo.isVariable() &&
1346          "empty or invalid DIVariable passed to dbg.value");
1347   if (!ValueFn)
1348     ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
1349 
1350   Value *Args[] = { MDNode::get(V->getContext(), V),
1351                     ConstantInt::get(Type::getInt64Ty(V->getContext()), Offset),
1352                     VarInfo };
1353   return CallInst::Create(ValueFn, Args, "", InsertAtEnd);
1354 }
1355