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 }
297 
298 /// isCompileUnit - Return true if the specified tag is DW_TAG_compile_unit.
299 bool DIDescriptor::isCompileUnit() const {
300   return DbgNode && getTag() == dwarf::DW_TAG_compile_unit;
301 }
302 
303 /// isFile - Return true if the specified tag is DW_TAG_file_type.
304 bool DIDescriptor::isFile() const {
305   return DbgNode && getTag() == dwarf::DW_TAG_file_type;
306 }
307 
308 /// isNameSpace - Return true if the specified tag is DW_TAG_namespace.
309 bool DIDescriptor::isNameSpace() const {
310   return DbgNode && getTag() == dwarf::DW_TAG_namespace;
311 }
312 
313 /// isLexicalBlockFile - Return true if the specified descriptor is a
314 /// lexical block with an extra file.
315 bool DIDescriptor::isLexicalBlockFile() const {
316   return DbgNode && getTag() == dwarf::DW_TAG_lexical_block &&
317     (DbgNode->getNumOperands() == 3);
318 }
319 
320 /// isLexicalBlock - Return true if the specified tag is DW_TAG_lexical_block.
321 bool DIDescriptor::isLexicalBlock() const {
322   return DbgNode && getTag() == dwarf::DW_TAG_lexical_block &&
323     (DbgNode->getNumOperands() > 3);
324 }
325 
326 /// isSubrange - Return true if the specified tag is DW_TAG_subrange_type.
327 bool DIDescriptor::isSubrange() const {
328   return DbgNode && getTag() == dwarf::DW_TAG_subrange_type;
329 }
330 
331 /// isEnumerator - Return true if the specified tag is DW_TAG_enumerator.
332 bool DIDescriptor::isEnumerator() const {
333   return DbgNode && getTag() == dwarf::DW_TAG_enumerator;
334 }
335 
336 /// isObjCProperty - Return true if the specified tag is DW_TAG_APPLE_property.
337 bool DIDescriptor::isObjCProperty() const {
338   return DbgNode && getTag() == dwarf::DW_TAG_APPLE_property;
339 }
340 
341 /// \brief Return true if the specified tag is DW_TAG_imported_module or
342 /// DW_TAG_imported_declaration.
343 bool DIDescriptor::isImportedEntity() const {
344   return DbgNode && (getTag() == dwarf::DW_TAG_imported_module ||
345                      getTag() == dwarf::DW_TAG_imported_declaration);
346 }
347 
348 //===----------------------------------------------------------------------===//
349 // Simple Descriptor Constructors and other Methods
350 //===----------------------------------------------------------------------===//
351 
352 DIType::DIType(const MDNode *N) : DIScope(N) {
353   if (!N) return;
354   if (!isType())
355     DbgNode = 0;
356 }
357 
358 unsigned DIArray::getNumElements() const {
359   if (!DbgNode)
360     return 0;
361   return DbgNode->getNumOperands();
362 }
363 
364 /// replaceAllUsesWith - Replace all uses of debug info referenced by
365 /// this descriptor.
366 void DIType::replaceAllUsesWith(DIDescriptor &D) {
367   if (!DbgNode)
368     return;
369 
370   // Since we use a TrackingVH for the node, its easy for clients to manufacture
371   // legitimate situations where they want to replaceAllUsesWith() on something
372   // which, due to uniquing, has merged with the source. We shield clients from
373   // this detail by allowing a value to be replaced with replaceAllUsesWith()
374   // itself.
375   if (DbgNode != D) {
376     MDNode *Node = const_cast<MDNode*>(DbgNode);
377     const MDNode *DN = D;
378     const Value *V = cast_or_null<Value>(DN);
379     Node->replaceAllUsesWith(const_cast<Value*>(V));
380     MDNode::deleteTemporary(Node);
381   }
382 }
383 
384 /// replaceAllUsesWith - Replace all uses of debug info referenced by
385 /// this descriptor.
386 void DIType::replaceAllUsesWith(MDNode *D) {
387   if (!DbgNode)
388     return;
389 
390   // Since we use a TrackingVH for the node, its easy for clients to manufacture
391   // legitimate situations where they want to replaceAllUsesWith() on something
392   // which, due to uniquing, has merged with the source. We shield clients from
393   // this detail by allowing a value to be replaced with replaceAllUsesWith()
394   // itself.
395   if (DbgNode != D) {
396     MDNode *Node = const_cast<MDNode*>(DbgNode);
397     const MDNode *DN = D;
398     const Value *V = cast_or_null<Value>(DN);
399     Node->replaceAllUsesWith(const_cast<Value*>(V));
400     MDNode::deleteTemporary(Node);
401   }
402 }
403 
404 /// isUnsignedDIType - Return true if type encoding is unsigned.
405 bool DIType::isUnsignedDIType() {
406   DIDerivedType DTy(DbgNode);
407   if (DTy.Verify())
408     return DTy.getTypeDerivedFrom().isUnsignedDIType();
409 
410   DIBasicType BTy(DbgNode);
411   if (BTy.Verify()) {
412     unsigned Encoding = BTy.getEncoding();
413     if (Encoding == dwarf::DW_ATE_unsigned ||
414         Encoding == dwarf::DW_ATE_unsigned_char ||
415         Encoding == dwarf::DW_ATE_boolean)
416       return true;
417   }
418   return false;
419 }
420 
421 /// Verify - Verify that a compile unit is well formed.
422 bool DICompileUnit::Verify() const {
423   if (!isCompileUnit())
424     return false;
425   StringRef N = getFilename();
426   if (N.empty())
427     return false;
428   // It is possible that directory and produce string is empty.
429   return DbgNode->getNumOperands() == 13;
430 }
431 
432 /// Verify - Verify that an ObjC property is well formed.
433 bool DIObjCProperty::Verify() const {
434   if (!isObjCProperty())
435     return false;
436 
437   DIType Ty = getType();
438   if (!Ty.Verify()) return false;
439 
440   // Don't worry about the rest of the strings for now.
441   return DbgNode->getNumOperands() == 8;
442 }
443 
444 /// Verify - Verify that a type descriptor is well formed.
445 bool DIType::Verify() const {
446   if (!isType())
447     return false;
448   if (getContext() && !getContext().Verify())
449     return false;
450   unsigned Tag = getTag();
451   if (!isBasicType() && Tag != dwarf::DW_TAG_const_type &&
452       Tag != dwarf::DW_TAG_volatile_type && Tag != dwarf::DW_TAG_pointer_type &&
453       Tag != dwarf::DW_TAG_ptr_to_member_type &&
454       Tag != dwarf::DW_TAG_reference_type &&
455       Tag != dwarf::DW_TAG_rvalue_reference_type &&
456       Tag != dwarf::DW_TAG_restrict_type &&
457       Tag != dwarf::DW_TAG_array_type &&
458       Tag != dwarf::DW_TAG_enumeration_type &&
459       Tag != dwarf::DW_TAG_subroutine_type &&
460       getFilename().empty())
461     return false;
462   return true;
463 }
464 
465 /// Verify - Verify that a basic type descriptor is well formed.
466 bool DIBasicType::Verify() const {
467   return isBasicType() && DbgNode->getNumOperands() == 10;
468 }
469 
470 /// Verify - Verify that a derived type descriptor is well formed.
471 bool DIDerivedType::Verify() const {
472   return isDerivedType() && DbgNode->getNumOperands() >= 10 &&
473          DbgNode->getNumOperands() <= 14;
474 }
475 
476 /// Verify - Verify that a composite type descriptor is well formed.
477 bool DICompositeType::Verify() const {
478   if (!isCompositeType())
479     return false;
480   if (getContext() && !getContext().Verify())
481     return false;
482 
483   return DbgNode->getNumOperands() >= 10 && DbgNode->getNumOperands() <= 14;
484 }
485 
486 /// Verify - Verify that a subprogram descriptor is well formed.
487 bool DISubprogram::Verify() const {
488   if (!isSubprogram())
489     return false;
490 
491   if (getContext() && !getContext().Verify())
492     return false;
493 
494   DICompositeType Ty = getType();
495   if (!Ty.Verify())
496     return false;
497   return DbgNode->getNumOperands() == 20;
498 }
499 
500 /// Verify - Verify that a global variable descriptor is well formed.
501 bool DIGlobalVariable::Verify() const {
502   if (!isGlobalVariable())
503     return false;
504 
505   if (getDisplayName().empty())
506     return false;
507 
508   if (getContext() && !getContext().Verify())
509     return false;
510 
511   DIType Ty = getType();
512   if (!Ty.Verify())
513     return false;
514 
515   if (!getGlobal() && !getConstant())
516     return false;
517 
518   return DbgNode->getNumOperands() == 13;
519 }
520 
521 /// Verify - Verify that a variable descriptor is well formed.
522 bool DIVariable::Verify() const {
523   if (!isVariable())
524     return false;
525 
526   if (getContext() && !getContext().Verify())
527     return false;
528 
529   DIType Ty = getType();
530   if (!Ty.Verify())
531     return false;
532 
533   return DbgNode->getNumOperands() >= 8;
534 }
535 
536 /// Verify - Verify that a location descriptor is well formed.
537 bool DILocation::Verify() const {
538   if (!DbgNode)
539     return false;
540 
541   return DbgNode->getNumOperands() == 4;
542 }
543 
544 /// Verify - Verify that a namespace descriptor is well formed.
545 bool DINameSpace::Verify() const {
546   if (!isNameSpace())
547     return false;
548   return DbgNode->getNumOperands() == 5;
549 }
550 
551 /// \brief Retrieve the MDNode for the directory/file pair.
552 MDNode *DIFile::getFileNode() const {
553   return const_cast<MDNode*>(getNodeField(DbgNode, 1));
554 }
555 
556 /// \brief Verify that the file descriptor is well formed.
557 bool DIFile::Verify() const {
558   return isFile() && DbgNode->getNumOperands() == 2;
559 }
560 
561 /// \brief Verify that the enumerator descriptor is well formed.
562 bool DIEnumerator::Verify() const {
563   return isEnumerator() && DbgNode->getNumOperands() == 3;
564 }
565 
566 /// \brief Verify that the subrange descriptor is well formed.
567 bool DISubrange::Verify() const {
568   return isSubrange() && DbgNode->getNumOperands() == 3;
569 }
570 
571 /// \brief Verify that the lexical block descriptor is well formed.
572 bool DILexicalBlock::Verify() const {
573   return isLexicalBlock() && DbgNode->getNumOperands() == 6;
574 }
575 
576 /// \brief Verify that the file-scoped lexical block descriptor is well formed.
577 bool DILexicalBlockFile::Verify() const {
578   return isLexicalBlockFile() && DbgNode->getNumOperands() == 3;
579 }
580 
581 /// \brief Verify that the template type parameter descriptor is well formed.
582 bool DITemplateTypeParameter::Verify() const {
583   return isTemplateTypeParameter() && DbgNode->getNumOperands() == 7;
584 }
585 
586 /// \brief Verify that the template value parameter descriptor is well formed.
587 bool DITemplateValueParameter::Verify() const {
588   return isTemplateValueParameter() && DbgNode->getNumOperands() == 8;
589 }
590 
591 /// \brief Verify that the imported module descriptor is well formed.
592 bool DIImportedEntity::Verify() const {
593   return isImportedEntity() &&
594          (DbgNode->getNumOperands() == 4 || DbgNode->getNumOperands() == 5);
595 }
596 
597 /// getOriginalTypeSize - If this type is derived from a base type then
598 /// return base type size.
599 uint64_t DIDerivedType::getOriginalTypeSize() const {
600   unsigned Tag = getTag();
601 
602   if (Tag != dwarf::DW_TAG_member && Tag != dwarf::DW_TAG_typedef &&
603       Tag != dwarf::DW_TAG_const_type && Tag != dwarf::DW_TAG_volatile_type &&
604       Tag != dwarf::DW_TAG_restrict_type)
605     return getSizeInBits();
606 
607   DIType BaseType = getTypeDerivedFrom();
608 
609   // If this type is not derived from any type then take conservative approach.
610   if (!BaseType.isValid())
611     return getSizeInBits();
612 
613   // If this is a derived type, go ahead and get the base type, unless it's a
614   // reference then it's just the size of the field. Pointer types have no need
615   // of this since they're a different type of qualification on the type.
616   if (BaseType.getTag() == dwarf::DW_TAG_reference_type ||
617       BaseType.getTag() == dwarf::DW_TAG_rvalue_reference_type)
618     return getSizeInBits();
619 
620   if (BaseType.isDerivedType())
621     return DIDerivedType(BaseType).getOriginalTypeSize();
622 
623   return BaseType.getSizeInBits();
624 }
625 
626 /// getObjCProperty - Return property node, if this ivar is associated with one.
627 MDNode *DIDerivedType::getObjCProperty() const {
628   if (DbgNode->getNumOperands() <= 10)
629     return NULL;
630   return dyn_cast_or_null<MDNode>(DbgNode->getOperand(10));
631 }
632 
633 /// \brief Set the array of member DITypes.
634 void DICompositeType::setTypeArray(DIArray Elements, DIArray TParams) {
635   assert((!TParams || DbgNode->getNumOperands() == 14) &&
636          "If you're setting the template parameters this should include a slot "
637          "for that!");
638   TrackingVH<MDNode> N(*this);
639   N->replaceOperandWith(10, Elements);
640   if (TParams)
641     N->replaceOperandWith(13, TParams);
642   DbgNode = N;
643 }
644 
645 /// \brief Set the containing type.
646 void DICompositeType::setContainingType(DICompositeType ContainingType) {
647   TrackingVH<MDNode> N(*this);
648   N->replaceOperandWith(12, ContainingType);
649   DbgNode = N;
650 }
651 
652 /// isInlinedFnArgument - Return true if this variable provides debugging
653 /// information for an inlined function arguments.
654 bool DIVariable::isInlinedFnArgument(const Function *CurFn) {
655   assert(CurFn && "Invalid function");
656   if (!getContext().isSubprogram())
657     return false;
658   // This variable is not inlined function argument if its scope
659   // does not describe current function.
660   return !DISubprogram(getContext()).describes(CurFn);
661 }
662 
663 /// describes - Return true if this subprogram provides debugging
664 /// information for the function F.
665 bool DISubprogram::describes(const Function *F) {
666   assert(F && "Invalid function");
667   if (F == getFunction())
668     return true;
669   StringRef Name = getLinkageName();
670   if (Name.empty())
671     Name = getName();
672   if (F->getName() == Name)
673     return true;
674   return false;
675 }
676 
677 unsigned DISubprogram::isOptimized() const {
678   assert (DbgNode && "Invalid subprogram descriptor!");
679   if (DbgNode->getNumOperands() == 15)
680     return getUnsignedField(14);
681   return 0;
682 }
683 
684 MDNode *DISubprogram::getVariablesNodes() const {
685   if (!DbgNode || DbgNode->getNumOperands() <= 18)
686     return NULL;
687   return dyn_cast_or_null<MDNode>(DbgNode->getOperand(18));
688 }
689 
690 DIArray DISubprogram::getVariables() const {
691   if (!DbgNode || DbgNode->getNumOperands() <= 18)
692     return DIArray();
693   if (MDNode *T = dyn_cast_or_null<MDNode>(DbgNode->getOperand(18)))
694     return DIArray(T);
695   return DIArray();
696 }
697 
698 Value *DITemplateValueParameter::getValue() const {
699   return getField(DbgNode, 4);
700 }
701 
702 void DIScope::setFilename(StringRef Name, LLVMContext &Context) {
703   if (!DbgNode)
704     return;
705   MDString *MDName(MDString::get(Context, Name));
706   const_cast<MDNode*>(getNodeField(DbgNode, 1))->replaceOperandWith(0, MDName);
707 }
708 
709 StringRef DIScope::getFilename() const {
710   if (!DbgNode)
711     return StringRef();
712   return ::getStringField(getNodeField(DbgNode, 1), 0);
713 }
714 
715 StringRef DIScope::getDirectory() const {
716   if (!DbgNode)
717     return StringRef();
718   return ::getStringField(getNodeField(DbgNode, 1), 1);
719 }
720 
721 DIArray DICompileUnit::getEnumTypes() const {
722   if (!DbgNode || DbgNode->getNumOperands() < 13)
723     return DIArray();
724 
725   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(7)))
726     return DIArray(N);
727   return DIArray();
728 }
729 
730 DIArray DICompileUnit::getRetainedTypes() const {
731   if (!DbgNode || DbgNode->getNumOperands() < 13)
732     return DIArray();
733 
734   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(8)))
735     return DIArray(N);
736   return DIArray();
737 }
738 
739 DIArray DICompileUnit::getSubprograms() const {
740   if (!DbgNode || DbgNode->getNumOperands() < 13)
741     return DIArray();
742 
743   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(9)))
744     return DIArray(N);
745   return DIArray();
746 }
747 
748 
749 DIArray DICompileUnit::getGlobalVariables() const {
750   if (!DbgNode || DbgNode->getNumOperands() < 13)
751     return DIArray();
752 
753   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(10)))
754     return DIArray(N);
755   return DIArray();
756 }
757 
758 DIArray DICompileUnit::getImportedEntities() const {
759   if (!DbgNode || DbgNode->getNumOperands() < 13)
760     return DIArray();
761 
762   if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(11)))
763     return DIArray(N);
764   return DIArray();
765 }
766 
767 /// fixupSubprogramName - Replace contains special characters used
768 /// in a typical Objective-C names with '.' in a given string.
769 static void fixupSubprogramName(DISubprogram Fn, SmallVectorImpl<char> &Out) {
770   StringRef FName =
771       Fn.getFunction() ? Fn.getFunction()->getName() : Fn.getName();
772   FName = Function::getRealLinkageName(FName);
773 
774   StringRef Prefix("llvm.dbg.lv.");
775   Out.reserve(FName.size() + Prefix.size());
776   Out.append(Prefix.begin(), Prefix.end());
777 
778   bool isObjCLike = false;
779   for (size_t i = 0, e = FName.size(); i < e; ++i) {
780     char C = FName[i];
781     if (C == '[')
782       isObjCLike = true;
783 
784     if (isObjCLike && (C == '[' || C == ']' || C == ' ' || C == ':' ||
785                        C == '+' || C == '(' || C == ')'))
786       Out.push_back('.');
787     else
788       Out.push_back(C);
789   }
790 }
791 
792 /// getFnSpecificMDNode - Return a NameMDNode, if available, that is
793 /// suitable to hold function specific information.
794 NamedMDNode *llvm::getFnSpecificMDNode(const Module &M, DISubprogram Fn) {
795   SmallString<32> Name;
796   fixupSubprogramName(Fn, Name);
797   return M.getNamedMetadata(Name.str());
798 }
799 
800 /// getOrInsertFnSpecificMDNode - Return a NameMDNode that is suitable
801 /// to hold function specific information.
802 NamedMDNode *llvm::getOrInsertFnSpecificMDNode(Module &M, DISubprogram Fn) {
803   SmallString<32> Name;
804   fixupSubprogramName(Fn, Name);
805   return M.getOrInsertNamedMetadata(Name.str());
806 }
807 
808 /// createInlinedVariable - Create a new inlined variable based on current
809 /// variable.
810 /// @param DV            Current Variable.
811 /// @param InlinedScope  Location at current variable is inlined.
812 DIVariable llvm::createInlinedVariable(MDNode *DV, MDNode *InlinedScope,
813                                        LLVMContext &VMContext) {
814   SmallVector<Value *, 16> Elts;
815   // Insert inlined scope as 7th element.
816   for (unsigned i = 0, e = DV->getNumOperands(); i != e; ++i)
817     i == 7 ? Elts.push_back(InlinedScope) :
818              Elts.push_back(DV->getOperand(i));
819   return DIVariable(MDNode::get(VMContext, Elts));
820 }
821 
822 /// cleanseInlinedVariable - Remove inlined scope from the variable.
823 DIVariable llvm::cleanseInlinedVariable(MDNode *DV, LLVMContext &VMContext) {
824   SmallVector<Value *, 16> Elts;
825   // Insert inlined scope as 7th element.
826   for (unsigned i = 0, e = DV->getNumOperands(); i != e; ++i)
827     i == 7 ?
828       Elts.push_back(Constant::getNullValue(Type::getInt32Ty(VMContext))):
829       Elts.push_back(DV->getOperand(i));
830   return DIVariable(MDNode::get(VMContext, Elts));
831 }
832 
833 /// getDISubprogram - Find subprogram that is enclosing this scope.
834 DISubprogram llvm::getDISubprogram(const MDNode *Scope) {
835   DIDescriptor D(Scope);
836   if (D.isSubprogram())
837     return DISubprogram(Scope);
838 
839   if (D.isLexicalBlockFile())
840     return getDISubprogram(DILexicalBlockFile(Scope).getContext());
841 
842   if (D.isLexicalBlock())
843     return getDISubprogram(DILexicalBlock(Scope).getContext());
844 
845   return DISubprogram();
846 }
847 
848 /// getDICompositeType - Find underlying composite type.
849 DICompositeType llvm::getDICompositeType(DIType T) {
850   if (T.isCompositeType())
851     return DICompositeType(T);
852 
853   if (T.isDerivedType())
854     return getDICompositeType(DIDerivedType(T).getTypeDerivedFrom());
855 
856   return DICompositeType();
857 }
858 
859 /// isSubprogramContext - Return true if Context is either a subprogram
860 /// or another context nested inside a subprogram.
861 bool llvm::isSubprogramContext(const MDNode *Context) {
862   if (!Context)
863     return false;
864   DIDescriptor D(Context);
865   if (D.isSubprogram())
866     return true;
867   if (D.isType())
868     return isSubprogramContext(DIType(Context).getContext());
869   return false;
870 }
871 
872 //===----------------------------------------------------------------------===//
873 // DebugInfoFinder implementations.
874 //===----------------------------------------------------------------------===//
875 
876 /// processModule - Process entire module and collect debug info.
877 void DebugInfoFinder::processModule(const Module &M) {
878   if (NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu")) {
879     for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
880       DICompileUnit CU(CU_Nodes->getOperand(i));
881       addCompileUnit(CU);
882       DIArray GVs = CU.getGlobalVariables();
883       for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) {
884         DIGlobalVariable DIG(GVs.getElement(i));
885         if (addGlobalVariable(DIG))
886           processType(DIG.getType());
887       }
888       DIArray SPs = CU.getSubprograms();
889       for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
890         processSubprogram(DISubprogram(SPs.getElement(i)));
891       DIArray EnumTypes = CU.getEnumTypes();
892       for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
893         processType(DIType(EnumTypes.getElement(i)));
894       DIArray RetainedTypes = CU.getRetainedTypes();
895       for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i)
896         processType(DIType(RetainedTypes.getElement(i)));
897       // FIXME: We really shouldn't be bailing out after visiting just one CU
898       return;
899     }
900   }
901 }
902 
903 /// processLocation - Process DILocation.
904 void DebugInfoFinder::processLocation(DILocation Loc) {
905   if (!Loc.Verify()) return;
906   DIDescriptor S(Loc.getScope());
907   if (S.isCompileUnit())
908     addCompileUnit(DICompileUnit(S));
909   else if (S.isSubprogram())
910     processSubprogram(DISubprogram(S));
911   else if (S.isLexicalBlock())
912     processLexicalBlock(DILexicalBlock(S));
913   else if (S.isLexicalBlockFile()) {
914     DILexicalBlockFile DBF = DILexicalBlockFile(S);
915     processLexicalBlock(DILexicalBlock(DBF.getScope()));
916   }
917   processLocation(Loc.getOrigLocation());
918 }
919 
920 /// processType - Process DIType.
921 void DebugInfoFinder::processType(DIType DT) {
922   if (!addType(DT))
923     return;
924   if (DT.isCompositeType()) {
925     DICompositeType DCT(DT);
926     processType(DCT.getTypeDerivedFrom());
927     DIArray DA = DCT.getTypeArray();
928     for (unsigned i = 0, e = DA.getNumElements(); i != e; ++i) {
929       DIDescriptor D = DA.getElement(i);
930       if (D.isType())
931         processType(DIType(D));
932       else if (D.isSubprogram())
933         processSubprogram(DISubprogram(D));
934     }
935   } else if (DT.isDerivedType()) {
936     DIDerivedType DDT(DT);
937     processType(DDT.getTypeDerivedFrom());
938   }
939 }
940 
941 /// processLexicalBlock
942 void DebugInfoFinder::processLexicalBlock(DILexicalBlock LB) {
943   DIScope Context = LB.getContext();
944   if (Context.isLexicalBlock())
945     return processLexicalBlock(DILexicalBlock(Context));
946   else if (Context.isLexicalBlockFile()) {
947     DILexicalBlockFile DBF = DILexicalBlockFile(Context);
948     return processLexicalBlock(DILexicalBlock(DBF.getScope()));
949   }
950   else
951     return processSubprogram(DISubprogram(Context));
952 }
953 
954 /// processSubprogram - Process DISubprogram.
955 void DebugInfoFinder::processSubprogram(DISubprogram SP) {
956   if (!addSubprogram(SP))
957     return;
958   processType(SP.getType());
959 }
960 
961 /// processDeclare - Process DbgDeclareInst.
962 void DebugInfoFinder::processDeclare(const DbgDeclareInst *DDI) {
963   MDNode *N = dyn_cast<MDNode>(DDI->getVariable());
964   if (!N) return;
965 
966   DIDescriptor DV(N);
967   if (!DV.isVariable())
968     return;
969 
970   if (!NodesSeen.insert(DV))
971     return;
972   processType(DIVariable(N).getType());
973 }
974 
975 /// addType - Add type into Tys.
976 bool DebugInfoFinder::addType(DIType DT) {
977   if (!DT.isValid())
978     return false;
979 
980   if (!NodesSeen.insert(DT))
981     return false;
982 
983   TYs.push_back(DT);
984   return true;
985 }
986 
987 /// addCompileUnit - Add compile unit into CUs.
988 bool DebugInfoFinder::addCompileUnit(DICompileUnit CU) {
989   if (!CU.Verify())
990     return false;
991 
992   if (!NodesSeen.insert(CU))
993     return false;
994 
995   CUs.push_back(CU);
996   return true;
997 }
998 
999 /// addGlobalVariable - Add global variable into GVs.
1000 bool DebugInfoFinder::addGlobalVariable(DIGlobalVariable DIG) {
1001   if (!DIDescriptor(DIG).isGlobalVariable())
1002     return false;
1003 
1004   if (!NodesSeen.insert(DIG))
1005     return false;
1006 
1007   GVs.push_back(DIG);
1008   return true;
1009 }
1010 
1011 // addSubprogram - Add subprgoram into SPs.
1012 bool DebugInfoFinder::addSubprogram(DISubprogram SP) {
1013   if (!DIDescriptor(SP).isSubprogram())
1014     return false;
1015 
1016   if (!NodesSeen.insert(SP))
1017     return false;
1018 
1019   SPs.push_back(SP);
1020   return true;
1021 }
1022 
1023 //===----------------------------------------------------------------------===//
1024 // DIDescriptor: dump routines for all descriptors.
1025 //===----------------------------------------------------------------------===//
1026 
1027 /// dump - Print descriptor to dbgs() with a newline.
1028 void DIDescriptor::dump() const {
1029   print(dbgs()); dbgs() << '\n';
1030 }
1031 
1032 /// print - Print descriptor.
1033 void DIDescriptor::print(raw_ostream &OS) const {
1034   if (!DbgNode) return;
1035 
1036   if (const char *Tag = dwarf::TagString(getTag()))
1037     OS << "[ " << Tag << " ]";
1038 
1039   if (this->isSubrange()) {
1040     DISubrange(DbgNode).printInternal(OS);
1041   } else if (this->isCompileUnit()) {
1042     DICompileUnit(DbgNode).printInternal(OS);
1043   } else if (this->isFile()) {
1044     DIFile(DbgNode).printInternal(OS);
1045   } else if (this->isEnumerator()) {
1046     DIEnumerator(DbgNode).printInternal(OS);
1047   } else if (this->isBasicType()) {
1048     DIType(DbgNode).printInternal(OS);
1049   } else if (this->isDerivedType()) {
1050     DIDerivedType(DbgNode).printInternal(OS);
1051   } else if (this->isCompositeType()) {
1052     DICompositeType(DbgNode).printInternal(OS);
1053   } else if (this->isSubprogram()) {
1054     DISubprogram(DbgNode).printInternal(OS);
1055   } else if (this->isGlobalVariable()) {
1056     DIGlobalVariable(DbgNode).printInternal(OS);
1057   } else if (this->isVariable()) {
1058     DIVariable(DbgNode).printInternal(OS);
1059   } else if (this->isObjCProperty()) {
1060     DIObjCProperty(DbgNode).printInternal(OS);
1061   } else if (this->isNameSpace()) {
1062     DINameSpace(DbgNode).printInternal(OS);
1063   } else if (this->isScope()) {
1064     DIScope(DbgNode).printInternal(OS);
1065   }
1066 }
1067 
1068 void DISubrange::printInternal(raw_ostream &OS) const {
1069   int64_t Count = getCount();
1070   if (Count != -1)
1071     OS << " [" << getLo() << ", " << Count - 1 << ']';
1072   else
1073     OS << " [unbounded]";
1074 }
1075 
1076 void DIScope::printInternal(raw_ostream &OS) const {
1077   OS << " [" << getDirectory() << "/" << getFilename() << ']';
1078 }
1079 
1080 void DICompileUnit::printInternal(raw_ostream &OS) const {
1081   DIScope::printInternal(OS);
1082   OS << " [";
1083   unsigned Lang = getLanguage();
1084   if (const char *LangStr = dwarf::LanguageString(Lang))
1085     OS << LangStr;
1086   else
1087     (OS << "lang 0x").write_hex(Lang);
1088   OS << ']';
1089 }
1090 
1091 void DIEnumerator::printInternal(raw_ostream &OS) const {
1092   OS << " [" << getName() << " :: " << getEnumValue() << ']';
1093 }
1094 
1095 void DIType::printInternal(raw_ostream &OS) const {
1096   if (!DbgNode) return;
1097 
1098   StringRef Res = getName();
1099   if (!Res.empty())
1100     OS << " [" << Res << "]";
1101 
1102   // TODO: Print context?
1103 
1104   OS << " [line " << getLineNumber()
1105      << ", size " << getSizeInBits()
1106      << ", align " << getAlignInBits()
1107      << ", offset " << getOffsetInBits();
1108   if (isBasicType())
1109     if (const char *Enc =
1110         dwarf::AttributeEncodingString(DIBasicType(DbgNode).getEncoding()))
1111       OS << ", enc " << Enc;
1112   OS << "]";
1113 
1114   if (isPrivate())
1115     OS << " [private]";
1116   else if (isProtected())
1117     OS << " [protected]";
1118 
1119   if (isArtificial())
1120     OS << " [artificial]";
1121 
1122   if (isForwardDecl())
1123     OS << " [fwd]";
1124   if (isVector())
1125     OS << " [vector]";
1126   if (isStaticMember())
1127     OS << " [static]";
1128 }
1129 
1130 void DIDerivedType::printInternal(raw_ostream &OS) const {
1131   DIType::printInternal(OS);
1132   OS << " [from " << getTypeDerivedFrom().getName() << ']';
1133 }
1134 
1135 void DICompositeType::printInternal(raw_ostream &OS) const {
1136   DIType::printInternal(OS);
1137   DIArray A = getTypeArray();
1138   OS << " [" << A.getNumElements() << " elements]";
1139 }
1140 
1141 void DINameSpace::printInternal(raw_ostream &OS) const {
1142   StringRef Name = getName();
1143   if (!Name.empty())
1144     OS << " [" << Name << ']';
1145 
1146   OS << " [line " << getLineNumber() << ']';
1147 }
1148 
1149 void DISubprogram::printInternal(raw_ostream &OS) const {
1150   // TODO : Print context
1151   OS << " [line " << getLineNumber() << ']';
1152 
1153   if (isLocalToUnit())
1154     OS << " [local]";
1155 
1156   if (isDefinition())
1157     OS << " [def]";
1158 
1159   if (getScopeLineNumber() != getLineNumber())
1160     OS << " [scope " << getScopeLineNumber() << "]";
1161 
1162   if (isPrivate())
1163     OS << " [private]";
1164   else if (isProtected())
1165     OS << " [protected]";
1166 
1167   StringRef Res = getName();
1168   if (!Res.empty())
1169     OS << " [" << Res << ']';
1170 }
1171 
1172 void DIGlobalVariable::printInternal(raw_ostream &OS) const {
1173   StringRef Res = getName();
1174   if (!Res.empty())
1175     OS << " [" << Res << ']';
1176 
1177   OS << " [line " << getLineNumber() << ']';
1178 
1179   // TODO : Print context
1180 
1181   if (isLocalToUnit())
1182     OS << " [local]";
1183 
1184   if (isDefinition())
1185     OS << " [def]";
1186 }
1187 
1188 void DIVariable::printInternal(raw_ostream &OS) const {
1189   StringRef Res = getName();
1190   if (!Res.empty())
1191     OS << " [" << Res << ']';
1192 
1193   OS << " [line " << getLineNumber() << ']';
1194 }
1195 
1196 void DIObjCProperty::printInternal(raw_ostream &OS) const {
1197   StringRef Name = getObjCPropertyName();
1198   if (!Name.empty())
1199     OS << " [" << Name << ']';
1200 
1201   OS << " [line " << getLineNumber()
1202      << ", properties " << getUnsignedField(6) << ']';
1203 }
1204 
1205 static void printDebugLoc(DebugLoc DL, raw_ostream &CommentOS,
1206                           const LLVMContext &Ctx) {
1207   if (!DL.isUnknown()) {          // Print source line info.
1208     DIScope Scope(DL.getScope(Ctx));
1209     // Omit the directory, because it's likely to be long and uninteresting.
1210     if (Scope.Verify())
1211       CommentOS << Scope.getFilename();
1212     else
1213       CommentOS << "<unknown>";
1214     CommentOS << ':' << DL.getLine();
1215     if (DL.getCol() != 0)
1216       CommentOS << ':' << DL.getCol();
1217     DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(DL.getInlinedAt(Ctx));
1218     if (!InlinedAtDL.isUnknown()) {
1219       CommentOS << " @[ ";
1220       printDebugLoc(InlinedAtDL, CommentOS, Ctx);
1221       CommentOS << " ]";
1222     }
1223   }
1224 }
1225 
1226 void DIVariable::printExtendedName(raw_ostream &OS) const {
1227   const LLVMContext &Ctx = DbgNode->getContext();
1228   StringRef Res = getName();
1229   if (!Res.empty())
1230     OS << Res << "," << getLineNumber();
1231   if (MDNode *InlinedAt = getInlinedAt()) {
1232     DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(InlinedAt);
1233     if (!InlinedAtDL.isUnknown()) {
1234       OS << " @[";
1235       printDebugLoc(InlinedAtDL, OS, Ctx);
1236       OS << "]";
1237     }
1238   }
1239 }
1240