1 //===--- DebugInfo.cpp - Debug Information Helper Classes -----------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the helper classes used to build and interpret debug
11 // information in LLVM IR form.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm/DebugInfo.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/ADT/SmallPtrSet.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/Analysis/ValueTracking.h"
20 #include "llvm/IR/Constants.h"
21 #include "llvm/IR/DerivedTypes.h"
22 #include "llvm/IR/Instructions.h"
23 #include "llvm/IR/IntrinsicInst.h"
24 #include "llvm/IR/Intrinsics.h"
25 #include "llvm/IR/Module.h"
26 #include "llvm/Support/Debug.h"
27 #include "llvm/Support/Dwarf.h"
28 #include "llvm/Support/ValueHandle.h"
29 #include "llvm/Support/raw_ostream.h"
30 using namespace llvm;
31 using namespace llvm::dwarf;
32 
33 //===----------------------------------------------------------------------===//
34 // DIDescriptor
35 //===----------------------------------------------------------------------===//
36 
37 DIDescriptor::DIDescriptor(const DIFile F) : DbgNode(F.DbgNode) {
38 }
39 
40 DIDescriptor::DIDescriptor(const DISubprogram F) : DbgNode(F.DbgNode) {
41 }
42 
43 DIDescriptor::DIDescriptor(const DILexicalBlockFile F) : DbgNode(F.DbgNode) {
44 }
45 
46 DIDescriptor::DIDescriptor(const DILexicalBlock F) : DbgNode(F.DbgNode) {
47 }
48 
49 DIDescriptor::DIDescriptor(const DIVariable F) : DbgNode(F.DbgNode) {
50 }
51 
52 DIDescriptor::DIDescriptor(const DIType F) : DbgNode(F.DbgNode) {
53 }
54 
55 bool DIDescriptor::Verify() const {
56   return DbgNode &&
57          (DIDerivedType(DbgNode).Verify() ||
58           DICompositeType(DbgNode).Verify() || DIBasicType(DbgNode).Verify() ||
59           DIVariable(DbgNode).Verify() || DISubprogram(DbgNode).Verify() ||
60           DIGlobalVariable(DbgNode).Verify() || DIFile(DbgNode).Verify() ||
61           DICompileUnit(DbgNode).Verify() || DINameSpace(DbgNode).Verify() ||
62           DILexicalBlock(DbgNode).Verify() ||
63           DILexicalBlockFile(DbgNode).Verify() ||
64           DISubrange(DbgNode).Verify() || DIEnumerator(DbgNode).Verify() ||
65           DIObjCProperty(DbgNode).Verify() ||
66           DITemplateTypeParameter(DbgNode).Verify() ||
67           DITemplateValueParameter(DbgNode).Verify() ||
68           DIImportedEntity(DbgNode).Verify());
69 }
70 
71 static Value *getField(const MDNode *DbgNode, unsigned Elt) {
72   if (DbgNode == 0 || Elt >= DbgNode->getNumOperands())
73     return 0;
74   return DbgNode->getOperand(Elt);
75 }
76 
77 static const MDNode *getNodeField(const MDNode *DbgNode, unsigned Elt) {
78   if (const MDNode *R = dyn_cast_or_null<MDNode>(getField(DbgNode, Elt)))
79     return R;
80   return 0;
81 }
82 
83 static StringRef getStringField(const MDNode *DbgNode, unsigned Elt) {
84   if (MDString *MDS = dyn_cast_or_null<MDString>(getField(DbgNode, Elt)))
85     return MDS->getString();
86   return StringRef();
87 }
88 
89 StringRef DIDescriptor::getStringField(unsigned Elt) const {
90   return ::getStringField(DbgNode, Elt);
91 }
92 
93 uint64_t DIDescriptor::getUInt64Field(unsigned Elt) const {
94   if (DbgNode == 0)
95     return 0;
96 
97   if (Elt < DbgNode->getNumOperands())
98     if (ConstantInt *CI
99         = dyn_cast_or_null<ConstantInt>(DbgNode->getOperand(Elt)))
100       return CI->getZExtValue();
101 
102   return 0;
103 }
104 
105 int64_t DIDescriptor::getInt64Field(unsigned Elt) const {
106   if (DbgNode == 0)
107     return 0;
108 
109   if (Elt < DbgNode->getNumOperands())
110     if (ConstantInt *CI
111         = dyn_cast_or_null<ConstantInt>(DbgNode->getOperand(Elt)))
112       return CI->getSExtValue();
113 
114   return 0;
115 }
116 
117 DIDescriptor DIDescriptor::getDescriptorField(unsigned Elt) const {
118   if (DbgNode == 0)
119     return DIDescriptor();
120 
121   if (Elt < DbgNode->getNumOperands())
122     return
123       DIDescriptor(dyn_cast_or_null<const MDNode>(DbgNode->getOperand(Elt)));
124   return DIDescriptor();
125 }
126 
127 GlobalVariable *DIDescriptor::getGlobalVariableField(unsigned Elt) const {
128   if (DbgNode == 0)
129     return 0;
130 
131   if (Elt < DbgNode->getNumOperands())
132       return dyn_cast_or_null<GlobalVariable>(DbgNode->getOperand(Elt));
133   return 0;
134 }
135 
136 Constant *DIDescriptor::getConstantField(unsigned Elt) const {
137   if (DbgNode == 0)
138     return 0;
139 
140   if (Elt < DbgNode->getNumOperands())
141       return dyn_cast_or_null<Constant>(DbgNode->getOperand(Elt));
142   return 0;
143 }
144 
145 Function *DIDescriptor::getFunctionField(unsigned Elt) const {
146   if (DbgNode == 0)
147     return 0;
148 
149   if (Elt < DbgNode->getNumOperands())
150       return dyn_cast_or_null<Function>(DbgNode->getOperand(Elt));
151   return 0;
152 }
153 
154 void DIDescriptor::replaceFunctionField(unsigned Elt, Function *F) {
155   if (DbgNode == 0)
156     return;
157 
158   if (Elt < DbgNode->getNumOperands()) {
159     MDNode *Node = const_cast<MDNode*>(DbgNode);
160     Node->replaceOperandWith(Elt, F);
161   }
162 }
163 
164 unsigned DIVariable::getNumAddrElements() const {
165   return DbgNode->getNumOperands()-8;
166 }
167 
168 /// getInlinedAt - If this variable is inlined then return inline location.
169 MDNode *DIVariable::getInlinedAt() const {
170   return dyn_cast_or_null<MDNode>(DbgNode->getOperand(7));
171 }
172 
173 //===----------------------------------------------------------------------===//
174 // Predicates
175 //===----------------------------------------------------------------------===//
176 
177 /// isBasicType - Return true if the specified tag is legal for
178 /// DIBasicType.
179 bool DIDescriptor::isBasicType() const {
180   if (!DbgNode) return false;
181   switch (getTag()) {
182   case dwarf::DW_TAG_base_type:
183   case dwarf::DW_TAG_unspecified_type:
184     return true;
185   default:
186     return false;
187   }
188 }
189 
190 /// isDerivedType - Return true if the specified tag is legal for DIDerivedType.
191 bool DIDescriptor::isDerivedType() const {
192   if (!DbgNode) return false;
193   switch (getTag()) {
194   case dwarf::DW_TAG_typedef:
195   case dwarf::DW_TAG_pointer_type:
196   case dwarf::DW_TAG_ptr_to_member_type:
197   case dwarf::DW_TAG_reference_type:
198   case dwarf::DW_TAG_rvalue_reference_type:
199   case dwarf::DW_TAG_const_type:
200   case dwarf::DW_TAG_volatile_type:
201   case dwarf::DW_TAG_restrict_type:
202   case dwarf::DW_TAG_member:
203   case dwarf::DW_TAG_inheritance:
204   case dwarf::DW_TAG_friend:
205     return true;
206   default:
207     // CompositeTypes are currently modelled as DerivedTypes.
208     return isCompositeType();
209   }
210 }
211 
212 /// isCompositeType - Return true if the specified tag is legal for
213 /// DICompositeType.
214 bool DIDescriptor::isCompositeType() const {
215   if (!DbgNode) return false;
216   switch (getTag()) {
217   case dwarf::DW_TAG_array_type:
218   case dwarf::DW_TAG_structure_type:
219   case dwarf::DW_TAG_union_type:
220   case dwarf::DW_TAG_enumeration_type:
221   case dwarf::DW_TAG_subroutine_type:
222   case dwarf::DW_TAG_class_type:
223     return true;
224   default:
225     return false;
226   }
227 }
228 
229 /// isVariable - Return true if the specified tag is legal for DIVariable.
230 bool DIDescriptor::isVariable() const {
231   if (!DbgNode) return false;
232   switch (getTag()) {
233   case dwarf::DW_TAG_auto_variable:
234   case dwarf::DW_TAG_arg_variable:
235     return true;
236   default:
237     return false;
238   }
239 }
240 
241 /// isType - Return true if the specified tag is legal for DIType.
242 bool DIDescriptor::isType() const {
243   return isBasicType() || isCompositeType() || isDerivedType();
244 }
245 
246 /// isSubprogram - Return true if the specified tag is legal for
247 /// DISubprogram.
248 bool DIDescriptor::isSubprogram() const {
249   return DbgNode && getTag() == dwarf::DW_TAG_subprogram;
250 }
251 
252 /// isGlobalVariable - Return true if the specified tag is legal for
253 /// DIGlobalVariable.
254 bool DIDescriptor::isGlobalVariable() const {
255   return DbgNode && (getTag() == dwarf::DW_TAG_variable ||
256                      getTag() == dwarf::DW_TAG_constant);
257 }
258 
259 /// isGlobal - Return true if the specified tag is legal for DIGlobal.
260 bool DIDescriptor::isGlobal() const {
261   return isGlobalVariable();
262 }
263 
264 /// isUnspecifiedParmeter - Return true if the specified tag is
265 /// DW_TAG_unspecified_parameters.
266 bool DIDescriptor::isUnspecifiedParameter() const {
267   return DbgNode && getTag() == dwarf::DW_TAG_unspecified_parameters;
268 }
269 
270 /// isScope - Return true if the specified tag is one of the scope
271 /// related tag.
272 bool DIDescriptor::isScope() const {
273   if (!DbgNode) return false;
274   switch (getTag()) {
275   case dwarf::DW_TAG_compile_unit:
276   case dwarf::DW_TAG_lexical_block:
277   case dwarf::DW_TAG_subprogram:
278   case dwarf::DW_TAG_namespace:
279     return true;
280   default:
281     break;
282   }
283   return false;
284 }
285 
286 /// isTemplateTypeParameter - Return true if the specified tag is
287 /// DW_TAG_template_type_parameter.
288 bool DIDescriptor::isTemplateTypeParameter() const {
289   return DbgNode && getTag() == dwarf::DW_TAG_template_type_parameter;
290 }
291 
292 /// isTemplateValueParameter - Return true if the specified tag is
293 /// DW_TAG_template_value_parameter.
294 bool DIDescriptor::isTemplateValueParameter() const {
295   return DbgNode && (getTag() == dwarf::DW_TAG_template_value_parameter ||
296                      getTag() == dwarf::DW_TAG_GNU_template_template_param ||
297                      getTag() == dwarf::DW_TAG_GNU_template_parameter_pack);
298 }
299 
300 /// isCompileUnit - Return true if the specified tag is DW_TAG_compile_unit.
301 bool DIDescriptor::isCompileUnit() const {
302   return DbgNode && getTag() == dwarf::DW_TAG_compile_unit;
303 }
304 
305 /// isFile - Return true if the specified tag is DW_TAG_file_type.
306 bool DIDescriptor::isFile() const {
307   return DbgNode && getTag() == dwarf::DW_TAG_file_type;
308 }
309 
310 /// isNameSpace - Return true if the specified tag is DW_TAG_namespace.
311 bool DIDescriptor::isNameSpace() const {
312   return DbgNode && getTag() == dwarf::DW_TAG_namespace;
313 }
314 
315 /// isLexicalBlockFile - Return true if the specified descriptor is a
316 /// lexical block with an extra file.
317 bool DIDescriptor::isLexicalBlockFile() const {
318   return DbgNode && getTag() == dwarf::DW_TAG_lexical_block &&
319     (DbgNode->getNumOperands() == 3);
320 }
321 
322 /// isLexicalBlock - Return true if the specified tag is DW_TAG_lexical_block.
323 bool DIDescriptor::isLexicalBlock() const {
324   return DbgNode && getTag() == dwarf::DW_TAG_lexical_block &&
325     (DbgNode->getNumOperands() > 3);
326 }
327 
328 /// isSubrange - Return true if the specified tag is DW_TAG_subrange_type.
329 bool DIDescriptor::isSubrange() const {
330   return DbgNode && getTag() == dwarf::DW_TAG_subrange_type;
331 }
332 
333 /// isEnumerator - Return true if the specified tag is DW_TAG_enumerator.
334 bool DIDescriptor::isEnumerator() const {
335   return DbgNode && getTag() == dwarf::DW_TAG_enumerator;
336 }
337 
338 /// isObjCProperty - Return true if the specified tag is DW_TAG_APPLE_property.
339 bool DIDescriptor::isObjCProperty() const {
340   return DbgNode && getTag() == dwarf::DW_TAG_APPLE_property;
341 }
342 
343 /// \brief Return true if the specified tag is DW_TAG_imported_module or
344 /// DW_TAG_imported_declaration.
345 bool DIDescriptor::isImportedEntity() const {
346   return DbgNode && (getTag() == dwarf::DW_TAG_imported_module ||
347                      getTag() == dwarf::DW_TAG_imported_declaration);
348 }
349 
350 //===----------------------------------------------------------------------===//
351 // Simple Descriptor Constructors and other Methods
352 //===----------------------------------------------------------------------===//
353 
354 DIType::DIType(const MDNode *N) : DIScope(N) {
355   if (!N) return;
356   if (!isType())
357     DbgNode = 0;
358 }
359 
360 unsigned DIArray::getNumElements() const {
361   if (!DbgNode)
362     return 0;
363   return DbgNode->getNumOperands();
364 }
365 
366 /// replaceAllUsesWith - Replace all uses of debug info referenced by
367 /// this descriptor.
368 void DIType::replaceAllUsesWith(DIDescriptor &D) {
369   if (!DbgNode)
370     return;
371 
372   // Since we use a TrackingVH for the node, its easy for clients to manufacture
373   // legitimate situations where they want to replaceAllUsesWith() on something
374   // which, due to uniquing, has merged with the source. We shield clients from
375   // this detail by allowing a value to be replaced with replaceAllUsesWith()
376   // itself.
377   if (DbgNode != D) {
378     MDNode *Node = const_cast<MDNode*>(DbgNode);
379     const MDNode *DN = D;
380     const Value *V = cast_or_null<Value>(DN);
381     Node->replaceAllUsesWith(const_cast<Value*>(V));
382     MDNode::deleteTemporary(Node);
383   }
384 }
385 
386 /// replaceAllUsesWith - Replace all uses of debug info referenced by
387 /// this descriptor.
388 void DIType::replaceAllUsesWith(MDNode *D) {
389   if (!DbgNode)
390     return;
391 
392   // Since we use a TrackingVH for the node, its easy for clients to manufacture
393   // legitimate situations where they want to replaceAllUsesWith() on something
394   // which, due to uniquing, has merged with the source. We shield clients from
395   // this detail by allowing a value to be replaced with replaceAllUsesWith()
396   // itself.
397   if (DbgNode != D) {
398     MDNode *Node = const_cast<MDNode*>(DbgNode);
399     const MDNode *DN = D;
400     const Value *V = cast_or_null<Value>(DN);
401     Node->replaceAllUsesWith(const_cast<Value*>(V));
402     MDNode::deleteTemporary(Node);
403   }
404 }
405 
406 /// isUnsignedDIType - Return true if type encoding is unsigned.
407 bool DIType::isUnsignedDIType() {
408   DIDerivedType DTy(DbgNode);
409   if (DTy.Verify())
410     return DTy.getTypeDerivedFrom().isUnsignedDIType();
411 
412   DIBasicType BTy(DbgNode);
413   if (BTy.Verify()) {
414     unsigned Encoding = BTy.getEncoding();
415     if (Encoding == dwarf::DW_ATE_unsigned ||
416         Encoding == dwarf::DW_ATE_unsigned_char ||
417         Encoding == dwarf::DW_ATE_boolean)
418       return true;
419   }
420   return false;
421 }
422 
423 /// Verify - Verify that a compile unit is well formed.
424 bool DICompileUnit::Verify() const {
425   if (!isCompileUnit())
426     return false;
427   StringRef N = getFilename();
428   if (N.empty())
429     return false;
430   // It is possible that directory and produce string is empty.
431   return DbgNode->getNumOperands() == 13;
432 }
433 
434 /// Verify - Verify that an ObjC property is well formed.
435 bool DIObjCProperty::Verify() const {
436   if (!isObjCProperty())
437     return false;
438 
439   DIType Ty = getType();
440   if (!Ty.Verify()) return false;
441 
442   // Don't worry about the rest of the strings for now.
443   return DbgNode->getNumOperands() == 8;
444 }
445 
446 /// Verify - Verify that a type descriptor is well formed.
447 bool DIType::Verify() const {
448   if (!isType())
449     return false;
450   if (getContext() && !getContext().Verify())
451     return false;
452   unsigned Tag = getTag();
453   if (!isBasicType() && Tag != dwarf::DW_TAG_const_type &&
454       Tag != dwarf::DW_TAG_volatile_type && Tag != dwarf::DW_TAG_pointer_type &&
455       Tag != dwarf::DW_TAG_ptr_to_member_type &&
456       Tag != dwarf::DW_TAG_reference_type &&
457       Tag != dwarf::DW_TAG_rvalue_reference_type &&
458       Tag != dwarf::DW_TAG_restrict_type &&
459       Tag != dwarf::DW_TAG_array_type &&
460       Tag != dwarf::DW_TAG_enumeration_type &&
461       Tag != dwarf::DW_TAG_subroutine_type &&
462       getFilename().empty())
463     return false;
464   return true;
465 }
466 
467 /// Verify - Verify that a basic type descriptor is well formed.
468 bool DIBasicType::Verify() const {
469   return isBasicType() && DbgNode->getNumOperands() == 10;
470 }
471 
472 /// Verify - Verify that a derived type descriptor is well formed.
473 bool DIDerivedType::Verify() const {
474   return isDerivedType() && DbgNode->getNumOperands() >= 10 &&
475          DbgNode->getNumOperands() <= 14;
476 }
477 
478 /// Verify - Verify that a composite type descriptor is well formed.
479 bool DICompositeType::Verify() const {
480   if (!isCompositeType())
481     return false;
482   if (getContext() && !getContext().Verify())
483     return false;
484 
485   return DbgNode->getNumOperands() >= 10 && DbgNode->getNumOperands() <= 14;
486 }
487 
488 /// Verify - Verify that a subprogram descriptor is well formed.
489 bool DISubprogram::Verify() const {
490   if (!isSubprogram())
491     return false;
492 
493   if (getContext() && !getContext().Verify())
494     return false;
495 
496   DICompositeType Ty = getType();
497   if (!Ty.Verify())
498     return false;
499   return DbgNode->getNumOperands() == 20;
500 }
501 
502 /// Verify - Verify that a global variable descriptor is well formed.
503 bool DIGlobalVariable::Verify() const {
504   if (!isGlobalVariable())
505     return false;
506 
507   if (getDisplayName().empty())
508     return false;
509 
510   if (getContext() && !getContext().Verify())
511     return false;
512 
513   DIType Ty = getType();
514   if (!Ty.Verify())
515     return false;
516 
517   if (!getGlobal() && !getConstant())
518     return false;
519 
520   return DbgNode->getNumOperands() == 13;
521 }
522 
523 /// Verify - Verify that a variable descriptor is well formed.
524 bool DIVariable::Verify() const {
525   if (!isVariable())
526     return false;
527 
528   if (getContext() && !getContext().Verify())
529     return false;
530 
531   DIType Ty = getType();
532   if (!Ty.Verify())
533     return false;
534 
535   return DbgNode->getNumOperands() >= 8;
536 }
537 
538 /// Verify - Verify that a location descriptor is well formed.
539 bool DILocation::Verify() const {
540   if (!DbgNode)
541     return false;
542 
543   return DbgNode->getNumOperands() == 4;
544 }
545 
546 /// Verify - Verify that a namespace descriptor is well formed.
547 bool DINameSpace::Verify() const {
548   if (!isNameSpace())
549     return false;
550   return DbgNode->getNumOperands() == 5;
551 }
552 
553 /// \brief Retrieve the MDNode for the directory/file pair.
554 MDNode *DIFile::getFileNode() const {
555   return const_cast<MDNode*>(getNodeField(DbgNode, 1));
556 }
557 
558 /// \brief Verify that the file descriptor is well formed.
559 bool DIFile::Verify() const {
560   return isFile() && DbgNode->getNumOperands() == 2;
561 }
562 
563 /// \brief Verify that the enumerator descriptor is well formed.
564 bool DIEnumerator::Verify() const {
565   return isEnumerator() && DbgNode->getNumOperands() == 3;
566 }
567 
568 /// \brief Verify that the subrange descriptor is well formed.
569 bool DISubrange::Verify() const {
570   return isSubrange() && DbgNode->getNumOperands() == 3;
571 }
572 
573 /// \brief Verify that the lexical block descriptor is well formed.
574 bool DILexicalBlock::Verify() const {
575   return isLexicalBlock() && DbgNode->getNumOperands() == 6;
576 }
577 
578 /// \brief Verify that the file-scoped lexical block descriptor is well formed.
579 bool DILexicalBlockFile::Verify() const {
580   return isLexicalBlockFile() && DbgNode->getNumOperands() == 3;
581 }
582 
583 /// \brief Verify that the template type parameter descriptor is well formed.
584 bool DITemplateTypeParameter::Verify() const {
585   return isTemplateTypeParameter() && DbgNode->getNumOperands() == 7;
586 }
587 
588 /// \brief Verify that the template value parameter descriptor is well formed.
589 bool DITemplateValueParameter::Verify() const {
590   return isTemplateValueParameter() && DbgNode->getNumOperands() == 8;
591 }
592 
593 /// \brief Verify that the imported module descriptor is well formed.
594 bool DIImportedEntity::Verify() const {
595   return isImportedEntity() &&
596          (DbgNode->getNumOperands() == 4 || DbgNode->getNumOperands() == 5);
597 }
598 
599 /// getOriginalTypeSize - If this type is derived from a base type then
600 /// return base type size.
601 uint64_t DIDerivedType::getOriginalTypeSize() const {
602   unsigned Tag = getTag();
603 
604   if (Tag != dwarf::DW_TAG_member && Tag != dwarf::DW_TAG_typedef &&
605       Tag != dwarf::DW_TAG_const_type && Tag != dwarf::DW_TAG_volatile_type &&
606       Tag != dwarf::DW_TAG_restrict_type)
607     return getSizeInBits();
608 
609   DIType BaseType = getTypeDerivedFrom();
610 
611   // If this type is not derived from any type then take conservative approach.
612   if (!BaseType.isValid())
613     return getSizeInBits();
614 
615   // If this is a derived type, go ahead and get the base type, unless it's a
616   // reference then it's just the size of the field. Pointer types have no need
617   // of this since they're a different type of qualification on the type.
618   if (BaseType.getTag() == dwarf::DW_TAG_reference_type ||
619       BaseType.getTag() == dwarf::DW_TAG_rvalue_reference_type)
620     return getSizeInBits();
621 
622   if (BaseType.isDerivedType())
623     return DIDerivedType(BaseType).getOriginalTypeSize();
624 
625   return BaseType.getSizeInBits();
626 }
627 
628 /// getObjCProperty - Return property node, if this ivar is associated with one.
629 MDNode *DIDerivedType::getObjCProperty() const {
630   if (DbgNode->getNumOperands() <= 10)
631     return NULL;
632   return dyn_cast_or_null<MDNode>(DbgNode->getOperand(10));
633 }
634 
635 /// \brief Set the array of member DITypes.
636 void DICompositeType::setTypeArray(DIArray Elements, DIArray TParams) {
637   assert((!TParams || DbgNode->getNumOperands() == 14) &&
638          "If you're setting the template parameters this should include a slot "
639          "for that!");
640   TrackingVH<MDNode> N(*this);
641   N->replaceOperandWith(10, Elements);
642   if (TParams)
643     N->replaceOperandWith(13, TParams);
644   DbgNode = N;
645 }
646 
647 /// \brief Set the containing type.
648 void DICompositeType::setContainingType(DICompositeType ContainingType) {
649   TrackingVH<MDNode> N(*this);
650   N->replaceOperandWith(12, ContainingType);
651   DbgNode = N;
652 }
653 
654 /// isInlinedFnArgument - Return true if this variable provides debugging
655 /// information for an inlined function arguments.
656 bool DIVariable::isInlinedFnArgument(const Function *CurFn) {
657   assert(CurFn && "Invalid function");
658   if (!getContext().isSubprogram())
659     return false;
660   // This variable is not inlined function argument if its scope
661   // does not describe current function.
662   return !DISubprogram(getContext()).describes(CurFn);
663 }
664 
665 /// describes - Return true if this subprogram provides debugging
666 /// information for the function F.
667 bool DISubprogram::describes(const Function *F) {
668   assert(F && "Invalid function");
669   if (F == getFunction())
670     return true;
671   StringRef Name = getLinkageName();
672   if (Name.empty())
673     Name = getName();
674   if (F->getName() == Name)
675     return true;
676   return false;
677 }
678 
679 unsigned DISubprogram::isOptimized() const {
680   assert (DbgNode && "Invalid subprogram descriptor!");
681   if (DbgNode->getNumOperands() == 15)
682     return getUnsignedField(14);
683   return 0;
684 }
685 
686 MDNode *DISubprogram::getVariablesNodes() const {
687   if (!DbgNode || DbgNode->getNumOperands() <= 18)
688     return NULL;
689   return dyn_cast_or_null<MDNode>(DbgNode->getOperand(18));
690 }
691 
692 DIArray DISubprogram::getVariables() const {
693   if (!DbgNode || DbgNode->getNumOperands() <= 18)
694     return DIArray();
695   if (MDNode *T = dyn_cast_or_null<MDNode>(DbgNode->getOperand(18)))
696     return DIArray(T);
697   return DIArray();
698 }
699 
700 Value *DITemplateValueParameter::getValue() const {
701   return getField(DbgNode, 4);
702 }
703 
704 void DIScope::setFilename(StringRef Name, LLVMContext &Context) {
705   if (!DbgNode)
706     return;
707   MDString *MDName(MDString::get(Context, Name));
708   const_cast<MDNode*>(getNodeField(DbgNode, 1))->replaceOperandWith(0, MDName);
709 }
710 
711 StringRef DIScope::getFilename() const {
712   if (!DbgNode)
713     return StringRef();
714   return ::getStringField(getNodeField(DbgNode, 1), 0);
715 }
716 
717 StringRef DIScope::getDirectory() const {
718   if (!DbgNode)
719     return StringRef();
720   return ::getStringField(getNodeField(DbgNode, 1), 1);
721 }
722 
723 DIArray DICompileUnit::getEnumTypes() const {
724   if (!DbgNode || DbgNode->getNumOperands() < 13)
725     return DIArray();
726 
727   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(7)))
728     return DIArray(N);
729   return DIArray();
730 }
731 
732 DIArray DICompileUnit::getRetainedTypes() const {
733   if (!DbgNode || DbgNode->getNumOperands() < 13)
734     return DIArray();
735 
736   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(8)))
737     return DIArray(N);
738   return DIArray();
739 }
740 
741 DIArray DICompileUnit::getSubprograms() const {
742   if (!DbgNode || DbgNode->getNumOperands() < 13)
743     return DIArray();
744 
745   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(9)))
746     return DIArray(N);
747   return DIArray();
748 }
749 
750 
751 DIArray DICompileUnit::getGlobalVariables() const {
752   if (!DbgNode || DbgNode->getNumOperands() < 13)
753     return DIArray();
754 
755   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(10)))
756     return DIArray(N);
757   return DIArray();
758 }
759 
760 DIArray DICompileUnit::getImportedEntities() const {
761   if (!DbgNode || DbgNode->getNumOperands() < 13)
762     return DIArray();
763 
764   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(11)))
765     return DIArray(N);
766   return DIArray();
767 }
768 
769 /// fixupSubprogramName - Replace contains special characters used
770 /// in a typical Objective-C names with '.' in a given string.
771 static void fixupSubprogramName(DISubprogram Fn, SmallVectorImpl<char> &Out) {
772   StringRef FName =
773       Fn.getFunction() ? Fn.getFunction()->getName() : Fn.getName();
774   FName = Function::getRealLinkageName(FName);
775 
776   StringRef Prefix("llvm.dbg.lv.");
777   Out.reserve(FName.size() + Prefix.size());
778   Out.append(Prefix.begin(), Prefix.end());
779 
780   bool isObjCLike = false;
781   for (size_t i = 0, e = FName.size(); i < e; ++i) {
782     char C = FName[i];
783     if (C == '[')
784       isObjCLike = true;
785 
786     if (isObjCLike && (C == '[' || C == ']' || C == ' ' || C == ':' ||
787                        C == '+' || C == '(' || C == ')'))
788       Out.push_back('.');
789     else
790       Out.push_back(C);
791   }
792 }
793 
794 /// getFnSpecificMDNode - Return a NameMDNode, if available, that is
795 /// suitable to hold function specific information.
796 NamedMDNode *llvm::getFnSpecificMDNode(const Module &M, DISubprogram Fn) {
797   SmallString<32> Name;
798   fixupSubprogramName(Fn, Name);
799   return M.getNamedMetadata(Name.str());
800 }
801 
802 /// getOrInsertFnSpecificMDNode - Return a NameMDNode that is suitable
803 /// to hold function specific information.
804 NamedMDNode *llvm::getOrInsertFnSpecificMDNode(Module &M, DISubprogram Fn) {
805   SmallString<32> Name;
806   fixupSubprogramName(Fn, Name);
807   return M.getOrInsertNamedMetadata(Name.str());
808 }
809 
810 /// createInlinedVariable - Create a new inlined variable based on current
811 /// variable.
812 /// @param DV            Current Variable.
813 /// @param InlinedScope  Location at current variable is inlined.
814 DIVariable llvm::createInlinedVariable(MDNode *DV, MDNode *InlinedScope,
815                                        LLVMContext &VMContext) {
816   SmallVector<Value *, 16> Elts;
817   // Insert inlined scope as 7th element.
818   for (unsigned i = 0, e = DV->getNumOperands(); i != e; ++i)
819     i == 7 ? Elts.push_back(InlinedScope) :
820              Elts.push_back(DV->getOperand(i));
821   return DIVariable(MDNode::get(VMContext, Elts));
822 }
823 
824 /// cleanseInlinedVariable - Remove inlined scope from the variable.
825 DIVariable llvm::cleanseInlinedVariable(MDNode *DV, LLVMContext &VMContext) {
826   SmallVector<Value *, 16> Elts;
827   // Insert inlined scope as 7th element.
828   for (unsigned i = 0, e = DV->getNumOperands(); i != e; ++i)
829     i == 7 ?
830       Elts.push_back(Constant::getNullValue(Type::getInt32Ty(VMContext))):
831       Elts.push_back(DV->getOperand(i));
832   return DIVariable(MDNode::get(VMContext, Elts));
833 }
834 
835 /// getDISubprogram - Find subprogram that is enclosing this scope.
836 DISubprogram llvm::getDISubprogram(const MDNode *Scope) {
837   DIDescriptor D(Scope);
838   if (D.isSubprogram())
839     return DISubprogram(Scope);
840 
841   if (D.isLexicalBlockFile())
842     return getDISubprogram(DILexicalBlockFile(Scope).getContext());
843 
844   if (D.isLexicalBlock())
845     return getDISubprogram(DILexicalBlock(Scope).getContext());
846 
847   return DISubprogram();
848 }
849 
850 /// getDICompositeType - Find underlying composite type.
851 DICompositeType llvm::getDICompositeType(DIType T) {
852   if (T.isCompositeType())
853     return DICompositeType(T);
854 
855   if (T.isDerivedType())
856     return getDICompositeType(DIDerivedType(T).getTypeDerivedFrom());
857 
858   return DICompositeType();
859 }
860 
861 /// isSubprogramContext - Return true if Context is either a subprogram
862 /// or another context nested inside a subprogram.
863 bool llvm::isSubprogramContext(const MDNode *Context) {
864   if (!Context)
865     return false;
866   DIDescriptor D(Context);
867   if (D.isSubprogram())
868     return true;
869   if (D.isType())
870     return isSubprogramContext(DIType(Context).getContext());
871   return false;
872 }
873 
874 //===----------------------------------------------------------------------===//
875 // DebugInfoFinder implementations.
876 //===----------------------------------------------------------------------===//
877 
878 /// processModule - Process entire module and collect debug info.
879 void DebugInfoFinder::processModule(const Module &M) {
880   if (NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu")) {
881     for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
882       DICompileUnit CU(CU_Nodes->getOperand(i));
883       addCompileUnit(CU);
884       DIArray GVs = CU.getGlobalVariables();
885       for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) {
886         DIGlobalVariable DIG(GVs.getElement(i));
887         if (addGlobalVariable(DIG))
888           processType(DIG.getType());
889       }
890       DIArray SPs = CU.getSubprograms();
891       for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
892         processSubprogram(DISubprogram(SPs.getElement(i)));
893       DIArray EnumTypes = CU.getEnumTypes();
894       for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
895         processType(DIType(EnumTypes.getElement(i)));
896       DIArray RetainedTypes = CU.getRetainedTypes();
897       for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i)
898         processType(DIType(RetainedTypes.getElement(i)));
899       // FIXME: We really shouldn't be bailing out after visiting just one CU
900       return;
901     }
902   }
903 }
904 
905 /// processLocation - Process DILocation.
906 void DebugInfoFinder::processLocation(DILocation Loc) {
907   if (!Loc.Verify()) return;
908   DIDescriptor S(Loc.getScope());
909   if (S.isCompileUnit())
910     addCompileUnit(DICompileUnit(S));
911   else if (S.isSubprogram())
912     processSubprogram(DISubprogram(S));
913   else if (S.isLexicalBlock())
914     processLexicalBlock(DILexicalBlock(S));
915   else if (S.isLexicalBlockFile()) {
916     DILexicalBlockFile DBF = DILexicalBlockFile(S);
917     processLexicalBlock(DILexicalBlock(DBF.getScope()));
918   }
919   processLocation(Loc.getOrigLocation());
920 }
921 
922 /// processType - Process DIType.
923 void DebugInfoFinder::processType(DIType DT) {
924   if (!addType(DT))
925     return;
926   if (DT.isCompositeType()) {
927     DICompositeType DCT(DT);
928     processType(DCT.getTypeDerivedFrom());
929     DIArray DA = DCT.getTypeArray();
930     for (unsigned i = 0, e = DA.getNumElements(); i != e; ++i) {
931       DIDescriptor D = DA.getElement(i);
932       if (D.isType())
933         processType(DIType(D));
934       else if (D.isSubprogram())
935         processSubprogram(DISubprogram(D));
936     }
937   } else if (DT.isDerivedType()) {
938     DIDerivedType DDT(DT);
939     processType(DDT.getTypeDerivedFrom());
940   }
941 }
942 
943 /// processLexicalBlock
944 void DebugInfoFinder::processLexicalBlock(DILexicalBlock LB) {
945   DIScope Context = LB.getContext();
946   if (Context.isLexicalBlock())
947     return processLexicalBlock(DILexicalBlock(Context));
948   else if (Context.isLexicalBlockFile()) {
949     DILexicalBlockFile DBF = DILexicalBlockFile(Context);
950     return processLexicalBlock(DILexicalBlock(DBF.getScope()));
951   }
952   else
953     return processSubprogram(DISubprogram(Context));
954 }
955 
956 /// processSubprogram - Process DISubprogram.
957 void DebugInfoFinder::processSubprogram(DISubprogram SP) {
958   if (!addSubprogram(SP))
959     return;
960   processType(SP.getType());
961 }
962 
963 /// processDeclare - Process DbgDeclareInst.
964 void DebugInfoFinder::processDeclare(const DbgDeclareInst *DDI) {
965   MDNode *N = dyn_cast<MDNode>(DDI->getVariable());
966   if (!N) return;
967 
968   DIDescriptor DV(N);
969   if (!DV.isVariable())
970     return;
971 
972   if (!NodesSeen.insert(DV))
973     return;
974   processType(DIVariable(N).getType());
975 }
976 
977 /// addType - Add type into Tys.
978 bool DebugInfoFinder::addType(DIType DT) {
979   if (!DT.isValid())
980     return false;
981 
982   if (!NodesSeen.insert(DT))
983     return false;
984 
985   TYs.push_back(DT);
986   return true;
987 }
988 
989 /// addCompileUnit - Add compile unit into CUs.
990 bool DebugInfoFinder::addCompileUnit(DICompileUnit CU) {
991   if (!CU.Verify())
992     return false;
993 
994   if (!NodesSeen.insert(CU))
995     return false;
996 
997   CUs.push_back(CU);
998   return true;
999 }
1000 
1001 /// addGlobalVariable - Add global variable into GVs.
1002 bool DebugInfoFinder::addGlobalVariable(DIGlobalVariable DIG) {
1003   if (!DIDescriptor(DIG).isGlobalVariable())
1004     return false;
1005 
1006   if (!NodesSeen.insert(DIG))
1007     return false;
1008 
1009   GVs.push_back(DIG);
1010   return true;
1011 }
1012 
1013 // addSubprogram - Add subprgoram into SPs.
1014 bool DebugInfoFinder::addSubprogram(DISubprogram SP) {
1015   if (!DIDescriptor(SP).isSubprogram())
1016     return false;
1017 
1018   if (!NodesSeen.insert(SP))
1019     return false;
1020 
1021   SPs.push_back(SP);
1022   return true;
1023 }
1024 
1025 //===----------------------------------------------------------------------===//
1026 // DIDescriptor: dump routines for all descriptors.
1027 //===----------------------------------------------------------------------===//
1028 
1029 /// dump - Print descriptor to dbgs() with a newline.
1030 void DIDescriptor::dump() const {
1031   print(dbgs()); dbgs() << '\n';
1032 }
1033 
1034 /// print - Print descriptor.
1035 void DIDescriptor::print(raw_ostream &OS) const {
1036   if (!DbgNode) return;
1037 
1038   if (const char *Tag = dwarf::TagString(getTag()))
1039     OS << "[ " << Tag << " ]";
1040 
1041   if (this->isSubrange()) {
1042     DISubrange(DbgNode).printInternal(OS);
1043   } else if (this->isCompileUnit()) {
1044     DICompileUnit(DbgNode).printInternal(OS);
1045   } else if (this->isFile()) {
1046     DIFile(DbgNode).printInternal(OS);
1047   } else if (this->isEnumerator()) {
1048     DIEnumerator(DbgNode).printInternal(OS);
1049   } else if (this->isBasicType()) {
1050     DIType(DbgNode).printInternal(OS);
1051   } else if (this->isDerivedType()) {
1052     DIDerivedType(DbgNode).printInternal(OS);
1053   } else if (this->isCompositeType()) {
1054     DICompositeType(DbgNode).printInternal(OS);
1055   } else if (this->isSubprogram()) {
1056     DISubprogram(DbgNode).printInternal(OS);
1057   } else if (this->isGlobalVariable()) {
1058     DIGlobalVariable(DbgNode).printInternal(OS);
1059   } else if (this->isVariable()) {
1060     DIVariable(DbgNode).printInternal(OS);
1061   } else if (this->isObjCProperty()) {
1062     DIObjCProperty(DbgNode).printInternal(OS);
1063   } else if (this->isNameSpace()) {
1064     DINameSpace(DbgNode).printInternal(OS);
1065   } else if (this->isScope()) {
1066     DIScope(DbgNode).printInternal(OS);
1067   }
1068 }
1069 
1070 void DISubrange::printInternal(raw_ostream &OS) const {
1071   int64_t Count = getCount();
1072   if (Count != -1)
1073     OS << " [" << getLo() << ", " << Count - 1 << ']';
1074   else
1075     OS << " [unbounded]";
1076 }
1077 
1078 void DIScope::printInternal(raw_ostream &OS) const {
1079   OS << " [" << getDirectory() << "/" << getFilename() << ']';
1080 }
1081 
1082 void DICompileUnit::printInternal(raw_ostream &OS) const {
1083   DIScope::printInternal(OS);
1084   OS << " [";
1085   unsigned Lang = getLanguage();
1086   if (const char *LangStr = dwarf::LanguageString(Lang))
1087     OS << LangStr;
1088   else
1089     (OS << "lang 0x").write_hex(Lang);
1090   OS << ']';
1091 }
1092 
1093 void DIEnumerator::printInternal(raw_ostream &OS) const {
1094   OS << " [" << getName() << " :: " << getEnumValue() << ']';
1095 }
1096 
1097 void DIType::printInternal(raw_ostream &OS) const {
1098   if (!DbgNode) return;
1099 
1100   StringRef Res = getName();
1101   if (!Res.empty())
1102     OS << " [" << Res << "]";
1103 
1104   // TODO: Print context?
1105 
1106   OS << " [line " << getLineNumber()
1107      << ", size " << getSizeInBits()
1108      << ", align " << getAlignInBits()
1109      << ", offset " << getOffsetInBits();
1110   if (isBasicType())
1111     if (const char *Enc =
1112         dwarf::AttributeEncodingString(DIBasicType(DbgNode).getEncoding()))
1113       OS << ", enc " << Enc;
1114   OS << "]";
1115 
1116   if (isPrivate())
1117     OS << " [private]";
1118   else if (isProtected())
1119     OS << " [protected]";
1120 
1121   if (isArtificial())
1122     OS << " [artificial]";
1123 
1124   if (isForwardDecl())
1125     OS << " [decl]";
1126   else if (getTag() == dwarf::DW_TAG_structure_type ||
1127            getTag() == dwarf::DW_TAG_union_type ||
1128            getTag() == dwarf::DW_TAG_enumeration_type ||
1129            getTag() == dwarf::DW_TAG_class_type)
1130     OS << " [def]";
1131   if (isVector())
1132     OS << " [vector]";
1133   if (isStaticMember())
1134     OS << " [static]";
1135 }
1136 
1137 void DIDerivedType::printInternal(raw_ostream &OS) const {
1138   DIType::printInternal(OS);
1139   OS << " [from " << getTypeDerivedFrom().getName() << ']';
1140 }
1141 
1142 void DICompositeType::printInternal(raw_ostream &OS) const {
1143   DIType::printInternal(OS);
1144   DIArray A = getTypeArray();
1145   OS << " [" << A.getNumElements() << " elements]";
1146 }
1147 
1148 void DINameSpace::printInternal(raw_ostream &OS) const {
1149   StringRef Name = getName();
1150   if (!Name.empty())
1151     OS << " [" << Name << ']';
1152 
1153   OS << " [line " << getLineNumber() << ']';
1154 }
1155 
1156 void DISubprogram::printInternal(raw_ostream &OS) const {
1157   // TODO : Print context
1158   OS << " [line " << getLineNumber() << ']';
1159 
1160   if (isLocalToUnit())
1161     OS << " [local]";
1162 
1163   if (isDefinition())
1164     OS << " [def]";
1165 
1166   if (getScopeLineNumber() != getLineNumber())
1167     OS << " [scope " << getScopeLineNumber() << "]";
1168 
1169   if (isPrivate())
1170     OS << " [private]";
1171   else if (isProtected())
1172     OS << " [protected]";
1173 
1174   StringRef Res = getName();
1175   if (!Res.empty())
1176     OS << " [" << Res << ']';
1177 }
1178 
1179 void DIGlobalVariable::printInternal(raw_ostream &OS) const {
1180   StringRef Res = getName();
1181   if (!Res.empty())
1182     OS << " [" << Res << ']';
1183 
1184   OS << " [line " << getLineNumber() << ']';
1185 
1186   // TODO : Print context
1187 
1188   if (isLocalToUnit())
1189     OS << " [local]";
1190 
1191   if (isDefinition())
1192     OS << " [def]";
1193 }
1194 
1195 void DIVariable::printInternal(raw_ostream &OS) const {
1196   StringRef Res = getName();
1197   if (!Res.empty())
1198     OS << " [" << Res << ']';
1199 
1200   OS << " [line " << getLineNumber() << ']';
1201 }
1202 
1203 void DIObjCProperty::printInternal(raw_ostream &OS) const {
1204   StringRef Name = getObjCPropertyName();
1205   if (!Name.empty())
1206     OS << " [" << Name << ']';
1207 
1208   OS << " [line " << getLineNumber()
1209      << ", properties " << getUnsignedField(6) << ']';
1210 }
1211 
1212 static void printDebugLoc(DebugLoc DL, raw_ostream &CommentOS,
1213                           const LLVMContext &Ctx) {
1214   if (!DL.isUnknown()) {          // Print source line info.
1215     DIScope Scope(DL.getScope(Ctx));
1216     // Omit the directory, because it's likely to be long and uninteresting.
1217     if (Scope.Verify())
1218       CommentOS << Scope.getFilename();
1219     else
1220       CommentOS << "<unknown>";
1221     CommentOS << ':' << DL.getLine();
1222     if (DL.getCol() != 0)
1223       CommentOS << ':' << DL.getCol();
1224     DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(DL.getInlinedAt(Ctx));
1225     if (!InlinedAtDL.isUnknown()) {
1226       CommentOS << " @[ ";
1227       printDebugLoc(InlinedAtDL, CommentOS, Ctx);
1228       CommentOS << " ]";
1229     }
1230   }
1231 }
1232 
1233 void DIVariable::printExtendedName(raw_ostream &OS) const {
1234   const LLVMContext &Ctx = DbgNode->getContext();
1235   StringRef Res = getName();
1236   if (!Res.empty())
1237     OS << Res << "," << getLineNumber();
1238   if (MDNode *InlinedAt = getInlinedAt()) {
1239     DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(InlinedAt);
1240     if (!InlinedAtDL.isUnknown()) {
1241       OS << " @[";
1242       printDebugLoc(InlinedAtDL, OS, Ctx);
1243       OS << "]";
1244     }
1245   }
1246 }
1247