--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/IR/DebugInfo.cpp	Wed May 15 06:43:32 2013 +0900
@@ -0,0 +1,1248 @@
+//===--- DebugInfo.cpp - Debug Information Helper Classes -----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the helper classes used to build and interpret debug
+// information in LLVM IR form.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Analysis/ValueTracking.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/Dwarf.h"
+#include "llvm/Support/ValueHandle.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+using namespace llvm::dwarf;
+
+//===----------------------------------------------------------------------===//
+// DIDescriptor
+//===----------------------------------------------------------------------===//
+
+DIDescriptor::DIDescriptor(const DIFile F) : DbgNode(F.DbgNode) {
+}
+
+DIDescriptor::DIDescriptor(const DISubprogram F) : DbgNode(F.DbgNode) {
+}
+
+DIDescriptor::DIDescriptor(const DILexicalBlockFile F) : DbgNode(F.DbgNode) {
+}
+
+DIDescriptor::DIDescriptor(const DILexicalBlock F) : DbgNode(F.DbgNode) {
+}
+
+DIDescriptor::DIDescriptor(const DIVariable F) : DbgNode(F.DbgNode) {
+}
+
+DIDescriptor::DIDescriptor(const DIType F) : DbgNode(F.DbgNode) {
+}
+
+bool DIDescriptor::Verify() const {
+  return DbgNode &&
+         (DIDerivedType(DbgNode).Verify() ||
+          DICompositeType(DbgNode).Verify() || DIBasicType(DbgNode).Verify() ||
+          DIVariable(DbgNode).Verify() || DISubprogram(DbgNode).Verify() ||
+          DIGlobalVariable(DbgNode).Verify() || DIFile(DbgNode).Verify() ||
+          DICompileUnit(DbgNode).Verify() || DINameSpace(DbgNode).Verify() ||
+          DILexicalBlock(DbgNode).Verify() ||
+          DILexicalBlockFile(DbgNode).Verify() ||
+          DISubrange(DbgNode).Verify() || DIEnumerator(DbgNode).Verify() ||
+          DIObjCProperty(DbgNode).Verify() ||
+          DITemplateTypeParameter(DbgNode).Verify() ||
+          DITemplateValueParameter(DbgNode).Verify() ||
+          DIImportedEntity(DbgNode).Verify());
+}
+
+static Value *getField(const MDNode *DbgNode, unsigned Elt) {
+  if (DbgNode == 0 || Elt >= DbgNode->getNumOperands())
+    return 0;
+  return DbgNode->getOperand(Elt);
+}
+
+static const MDNode *getNodeField(const MDNode *DbgNode, unsigned Elt) {
+  if (const MDNode *R = dyn_cast_or_null<MDNode>(getField(DbgNode, Elt)))
+    return R;
+  return 0;
+}
+
+static StringRef getStringField(const MDNode *DbgNode, unsigned Elt) {
+  if (MDString *MDS = dyn_cast_or_null<MDString>(getField(DbgNode, Elt)))
+    return MDS->getString();
+  return StringRef();
+}
+
+StringRef DIDescriptor::getStringField(unsigned Elt) const {
+  return ::getStringField(DbgNode, Elt);
+}
+
+uint64_t DIDescriptor::getUInt64Field(unsigned Elt) const {
+  if (DbgNode == 0)
+    return 0;
+
+  if (Elt < DbgNode->getNumOperands())
+    if (ConstantInt *CI
+        = dyn_cast_or_null<ConstantInt>(DbgNode->getOperand(Elt)))
+      return CI->getZExtValue();
+
+  return 0;
+}
+
+int64_t DIDescriptor::getInt64Field(unsigned Elt) const {
+  if (DbgNode == 0)
+    return 0;
+
+  if (Elt < DbgNode->getNumOperands())
+    if (ConstantInt *CI
+        = dyn_cast_or_null<ConstantInt>(DbgNode->getOperand(Elt)))
+      return CI->getSExtValue();
+
+  return 0;
+}
+
+DIDescriptor DIDescriptor::getDescriptorField(unsigned Elt) const {
+  if (DbgNode == 0)
+    return DIDescriptor();
+
+  if (Elt < DbgNode->getNumOperands())
+    return
+      DIDescriptor(dyn_cast_or_null<const MDNode>(DbgNode->getOperand(Elt)));
+  return DIDescriptor();
+}
+
+GlobalVariable *DIDescriptor::getGlobalVariableField(unsigned Elt) const {
+  if (DbgNode == 0)
+    return 0;
+
+  if (Elt < DbgNode->getNumOperands())
+      return dyn_cast_or_null<GlobalVariable>(DbgNode->getOperand(Elt));
+  return 0;
+}
+
+Constant *DIDescriptor::getConstantField(unsigned Elt) const {
+  if (DbgNode == 0)
+    return 0;
+
+  if (Elt < DbgNode->getNumOperands())
+      return dyn_cast_or_null<Constant>(DbgNode->getOperand(Elt));
+  return 0;
+}
+
+Function *DIDescriptor::getFunctionField(unsigned Elt) const {
+  if (DbgNode == 0)
+    return 0;
+
+  if (Elt < DbgNode->getNumOperands())
+      return dyn_cast_or_null<Function>(DbgNode->getOperand(Elt));
+  return 0;
+}
+
+void DIDescriptor::replaceFunctionField(unsigned Elt, Function *F) {
+  if (DbgNode == 0)
+    return;
+
+  if (Elt < DbgNode->getNumOperands()) {
+    MDNode *Node = const_cast<MDNode*>(DbgNode);
+    Node->replaceOperandWith(Elt, F);
+  }
+}
+
+unsigned DIVariable::getNumAddrElements() const {
+  return DbgNode->getNumOperands()-8;
+}
+
+/// getInlinedAt - If this variable is inlined then return inline location.
+MDNode *DIVariable::getInlinedAt() const {
+  return dyn_cast_or_null<MDNode>(DbgNode->getOperand(7));
+}
+
+//===----------------------------------------------------------------------===//
+// Predicates
+//===----------------------------------------------------------------------===//
+
+/// isBasicType - Return true if the specified tag is legal for
+/// DIBasicType.
+bool DIDescriptor::isBasicType() const {
+  if (!DbgNode) return false;
+  switch (getTag()) {
+  case dwarf::DW_TAG_base_type:
+  case dwarf::DW_TAG_unspecified_type:
+    return true;
+  default:
+    return false;
+  }
+}
+
+/// isDerivedType - Return true if the specified tag is legal for DIDerivedType.
+bool DIDescriptor::isDerivedType() const {
+  if (!DbgNode) return false;
+  switch (getTag()) {
+  case dwarf::DW_TAG_typedef:
+  case dwarf::DW_TAG_pointer_type:
+  case dwarf::DW_TAG_ptr_to_member_type:
+  case dwarf::DW_TAG_reference_type:
+  case dwarf::DW_TAG_rvalue_reference_type:
+  case dwarf::DW_TAG_const_type:
+  case dwarf::DW_TAG_volatile_type:
+  case dwarf::DW_TAG_restrict_type:
+  case dwarf::DW_TAG_member:
+  case dwarf::DW_TAG_inheritance:
+  case dwarf::DW_TAG_friend:
+    return true;
+  default:
+    // CompositeTypes are currently modelled as DerivedTypes.
+    return isCompositeType();
+  }
+}
+
+/// isCompositeType - Return true if the specified tag is legal for
+/// DICompositeType.
+bool DIDescriptor::isCompositeType() const {
+  if (!DbgNode) return false;
+  switch (getTag()) {
+  case dwarf::DW_TAG_array_type:
+  case dwarf::DW_TAG_structure_type:
+  case dwarf::DW_TAG_union_type:
+  case dwarf::DW_TAG_enumeration_type:
+  case dwarf::DW_TAG_subroutine_type:
+  case dwarf::DW_TAG_class_type:
+    return true;
+  default:
+    return false;
+  }
+}
+
+/// isVariable - Return true if the specified tag is legal for DIVariable.
+bool DIDescriptor::isVariable() const {
+  if (!DbgNode) return false;
+  switch (getTag()) {
+  case dwarf::DW_TAG_auto_variable:
+  case dwarf::DW_TAG_arg_variable:
+    return true;
+  default:
+    return false;
+  }
+}
+
+/// isType - Return true if the specified tag is legal for DIType.
+bool DIDescriptor::isType() const {
+  return isBasicType() || isCompositeType() || isDerivedType();
+}
+
+/// isSubprogram - Return true if the specified tag is legal for
+/// DISubprogram.
+bool DIDescriptor::isSubprogram() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_subprogram;
+}
+
+/// isGlobalVariable - Return true if the specified tag is legal for
+/// DIGlobalVariable.
+bool DIDescriptor::isGlobalVariable() const {
+  return DbgNode && (getTag() == dwarf::DW_TAG_variable ||
+                     getTag() == dwarf::DW_TAG_constant);
+}
+
+/// isGlobal - Return true if the specified tag is legal for DIGlobal.
+bool DIDescriptor::isGlobal() const {
+  return isGlobalVariable();
+}
+
+/// isUnspecifiedParmeter - Return true if the specified tag is
+/// DW_TAG_unspecified_parameters.
+bool DIDescriptor::isUnspecifiedParameter() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_unspecified_parameters;
+}
+
+/// isScope - Return true if the specified tag is one of the scope
+/// related tag.
+bool DIDescriptor::isScope() const {
+  if (!DbgNode) return false;
+  switch (getTag()) {
+  case dwarf::DW_TAG_compile_unit:
+  case dwarf::DW_TAG_lexical_block:
+  case dwarf::DW_TAG_subprogram:
+  case dwarf::DW_TAG_namespace:
+    return true;
+  default:
+    break;
+  }
+  return false;
+}
+
+/// isTemplateTypeParameter - Return true if the specified tag is
+/// DW_TAG_template_type_parameter.
+bool DIDescriptor::isTemplateTypeParameter() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_template_type_parameter;
+}
+
+/// isTemplateValueParameter - Return true if the specified tag is
+/// DW_TAG_template_value_parameter.
+bool DIDescriptor::isTemplateValueParameter() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_template_value_parameter;
+}
+
+/// isCompileUnit - Return true if the specified tag is DW_TAG_compile_unit.
+bool DIDescriptor::isCompileUnit() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_compile_unit;
+}
+
+/// isFile - Return true if the specified tag is DW_TAG_file_type.
+bool DIDescriptor::isFile() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_file_type;
+}
+
+/// isNameSpace - Return true if the specified tag is DW_TAG_namespace.
+bool DIDescriptor::isNameSpace() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_namespace;
+}
+
+/// isLexicalBlockFile - Return true if the specified descriptor is a
+/// lexical block with an extra file.
+bool DIDescriptor::isLexicalBlockFile() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_lexical_block &&
+    (DbgNode->getNumOperands() == 3);
+}
+
+/// isLexicalBlock - Return true if the specified tag is DW_TAG_lexical_block.
+bool DIDescriptor::isLexicalBlock() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_lexical_block &&
+    (DbgNode->getNumOperands() > 3);
+}
+
+/// isSubrange - Return true if the specified tag is DW_TAG_subrange_type.
+bool DIDescriptor::isSubrange() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_subrange_type;
+}
+
+/// isEnumerator - Return true if the specified tag is DW_TAG_enumerator.
+bool DIDescriptor::isEnumerator() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_enumerator;
+}
+
+/// isObjCProperty - Return true if the specified tag is DW_TAG_APPLE_property.
+bool DIDescriptor::isObjCProperty() const {
+  return DbgNode && getTag() == dwarf::DW_TAG_APPLE_property;
+}
+
+/// \brief Return true if the specified tag is DW_TAG_imported_module or
+/// DW_TAG_imported_declaration.
+bool DIDescriptor::isImportedEntity() const {
+  return DbgNode && (getTag() == dwarf::DW_TAG_imported_module ||
+                     getTag() == dwarf::DW_TAG_imported_declaration);
+}
+
+//===----------------------------------------------------------------------===//
+// Simple Descriptor Constructors and other Methods
+//===----------------------------------------------------------------------===//
+
+DIType::DIType(const MDNode *N) : DIScope(N) {
+  if (!N) return;
+  if (!isBasicType() && !isDerivedType() && !isCompositeType()) {
+    DbgNode = 0;
+  }
+}
+
+unsigned DIArray::getNumElements() const {
+  if (!DbgNode)
+    return 0;
+  return DbgNode->getNumOperands();
+}
+
+/// replaceAllUsesWith - Replace all uses of debug info referenced by
+/// this descriptor.
+void DIType::replaceAllUsesWith(DIDescriptor &D) {
+  if (!DbgNode)
+    return;
+
+  // Since we use a TrackingVH for the node, its easy for clients to manufacture
+  // legitimate situations where they want to replaceAllUsesWith() on something
+  // which, due to uniquing, has merged with the source. We shield clients from
+  // this detail by allowing a value to be replaced with replaceAllUsesWith()
+  // itself.
+  if (DbgNode != D) {
+    MDNode *Node = const_cast<MDNode*>(DbgNode);
+    const MDNode *DN = D;
+    const Value *V = cast_or_null<Value>(DN);
+    Node->replaceAllUsesWith(const_cast<Value*>(V));
+    MDNode::deleteTemporary(Node);
+  }
+}
+
+/// replaceAllUsesWith - Replace all uses of debug info referenced by
+/// this descriptor.
+void DIType::replaceAllUsesWith(MDNode *D) {
+  if (!DbgNode)
+    return;
+
+  // Since we use a TrackingVH for the node, its easy for clients to manufacture
+  // legitimate situations where they want to replaceAllUsesWith() on something
+  // which, due to uniquing, has merged with the source. We shield clients from
+  // this detail by allowing a value to be replaced with replaceAllUsesWith()
+  // itself.
+  if (DbgNode != D) {
+    MDNode *Node = const_cast<MDNode*>(DbgNode);
+    const MDNode *DN = D;
+    const Value *V = cast_or_null<Value>(DN);
+    Node->replaceAllUsesWith(const_cast<Value*>(V));
+    MDNode::deleteTemporary(Node);
+  }
+}
+
+/// isUnsignedDIType - Return true if type encoding is unsigned.
+bool DIType::isUnsignedDIType() {
+  DIDerivedType DTy(DbgNode);
+  if (DTy.Verify())
+    return DTy.getTypeDerivedFrom().isUnsignedDIType();
+
+  DIBasicType BTy(DbgNode);
+  if (BTy.Verify()) {
+    unsigned Encoding = BTy.getEncoding();
+    if (Encoding == dwarf::DW_ATE_unsigned ||
+        Encoding == dwarf::DW_ATE_unsigned_char ||
+        Encoding == dwarf::DW_ATE_boolean)
+      return true;
+  }
+  return false;
+}
+
+/// Verify - Verify that a compile unit is well formed.
+bool DICompileUnit::Verify() const {
+  if (!isCompileUnit())
+    return false;
+  StringRef N = getFilename();
+  if (N.empty())
+    return false;
+  // It is possible that directory and produce string is empty.
+  return DbgNode->getNumOperands() == 13;
+}
+
+/// Verify - Verify that an ObjC property is well formed.
+bool DIObjCProperty::Verify() const {
+  if (!isObjCProperty())
+    return false;
+
+  DIType Ty = getType();
+  if (!Ty.Verify()) return false;
+
+  // Don't worry about the rest of the strings for now.
+  return DbgNode->getNumOperands() == 8;
+}
+
+/// Verify - Verify that a type descriptor is well formed.
+bool DIType::Verify() const {
+  if (!isType())
+    return false;
+  if (getContext() && !getContext().Verify())
+    return false;
+  unsigned Tag = getTag();
+  if (!isBasicType() && Tag != dwarf::DW_TAG_const_type &&
+      Tag != dwarf::DW_TAG_volatile_type && Tag != dwarf::DW_TAG_pointer_type &&
+      Tag != dwarf::DW_TAG_ptr_to_member_type &&
+      Tag != dwarf::DW_TAG_reference_type &&
+      Tag != dwarf::DW_TAG_rvalue_reference_type &&
+      Tag != dwarf::DW_TAG_restrict_type &&
+      Tag != dwarf::DW_TAG_array_type &&
+      Tag != dwarf::DW_TAG_enumeration_type &&
+      Tag != dwarf::DW_TAG_subroutine_type &&
+      getFilename().empty())
+    return false;
+  return true;
+}
+
+/// Verify - Verify that a basic type descriptor is well formed.
+bool DIBasicType::Verify() const {
+  return isBasicType() && DbgNode->getNumOperands() == 10;
+}
+
+/// Verify - Verify that a derived type descriptor is well formed.
+bool DIDerivedType::Verify() const {
+  return isDerivedType() && DbgNode->getNumOperands() >= 10 &&
+         DbgNode->getNumOperands() <= 14;
+}
+
+/// Verify - Verify that a composite type descriptor is well formed.
+bool DICompositeType::Verify() const {
+  if (!isCompositeType())
+    return false;
+  if (getContext() && !getContext().Verify())
+    return false;
+
+  return DbgNode->getNumOperands() >= 10 && DbgNode->getNumOperands() <= 14;
+}
+
+/// Verify - Verify that a subprogram descriptor is well formed.
+bool DISubprogram::Verify() const {
+  if (!isSubprogram())
+    return false;
+
+  if (getContext() && !getContext().Verify())
+    return false;
+
+  DICompositeType Ty = getType();
+  if (!Ty.Verify())
+    return false;
+  return DbgNode->getNumOperands() == 20;
+}
+
+/// Verify - Verify that a global variable descriptor is well formed.
+bool DIGlobalVariable::Verify() const {
+  if (!isGlobalVariable())
+    return false;
+
+  if (getDisplayName().empty())
+    return false;
+
+  if (getContext() && !getContext().Verify())
+    return false;
+
+  DIType Ty = getType();
+  if (!Ty.Verify())
+    return false;
+
+  if (!getGlobal() && !getConstant())
+    return false;
+
+  return DbgNode->getNumOperands() == 13;
+}
+
+/// Verify - Verify that a variable descriptor is well formed.
+bool DIVariable::Verify() const {
+  if (!isVariable())
+    return false;
+
+  if (getContext() && !getContext().Verify())
+    return false;
+
+  DIType Ty = getType();
+  if (!Ty.Verify())
+    return false;
+
+  return DbgNode->getNumOperands() >= 8;
+}
+
+/// Verify - Verify that a location descriptor is well formed.
+bool DILocation::Verify() const {
+  if (!DbgNode)
+    return false;
+
+  return DbgNode->getNumOperands() == 4;
+}
+
+/// Verify - Verify that a namespace descriptor is well formed.
+bool DINameSpace::Verify() const {
+  if (!isNameSpace())
+    return false;
+  return DbgNode->getNumOperands() == 5;
+}
+
+/// \brief Retrieve the MDNode for the directory/file pair.
+MDNode *DIFile::getFileNode() const {
+  return const_cast<MDNode*>(getNodeField(DbgNode, 1));
+}
+
+/// \brief Verify that the file descriptor is well formed.
+bool DIFile::Verify() const {
+  return isFile() && DbgNode->getNumOperands() == 2;
+}
+
+/// \brief Verify that the enumerator descriptor is well formed.
+bool DIEnumerator::Verify() const {
+  return isEnumerator() && DbgNode->getNumOperands() == 3;
+}
+
+/// \brief Verify that the subrange descriptor is well formed.
+bool DISubrange::Verify() const {
+  return isSubrange() && DbgNode->getNumOperands() == 3;
+}
+
+/// \brief Verify that the lexical block descriptor is well formed.
+bool DILexicalBlock::Verify() const {
+  return isLexicalBlock() && DbgNode->getNumOperands() == 6;
+}
+
+/// \brief Verify that the file-scoped lexical block descriptor is well formed.
+bool DILexicalBlockFile::Verify() const {
+  return isLexicalBlockFile() && DbgNode->getNumOperands() == 3;
+}
+
+/// \brief Verify that the template type parameter descriptor is well formed.
+bool DITemplateTypeParameter::Verify() const {
+  return isTemplateTypeParameter() && DbgNode->getNumOperands() == 7;
+}
+
+/// \brief Verify that the template value parameter descriptor is well formed.
+bool DITemplateValueParameter::Verify() const {
+  return isTemplateValueParameter() && DbgNode->getNumOperands() == 8;
+}
+
+/// \brief Verify that the imported module descriptor is well formed.
+bool DIImportedEntity::Verify() const {
+  return isImportedEntity() && DbgNode->getNumOperands() == 4;
+}
+
+/// getOriginalTypeSize - If this type is derived from a base type then
+/// return base type size.
+uint64_t DIDerivedType::getOriginalTypeSize() const {
+  unsigned Tag = getTag();
+
+  if (Tag != dwarf::DW_TAG_member && Tag != dwarf::DW_TAG_typedef &&
+      Tag != dwarf::DW_TAG_const_type && Tag != dwarf::DW_TAG_volatile_type &&
+      Tag != dwarf::DW_TAG_restrict_type)
+    return getSizeInBits();
+
+  DIType BaseType = getTypeDerivedFrom();
+
+  // If this type is not derived from any type then take conservative approach.
+  if (!BaseType.isValid())
+    return getSizeInBits();
+
+  // If this is a derived type, go ahead and get the base type, unless it's a
+  // reference then it's just the size of the field. Pointer types have no need
+  // of this since they're a different type of qualification on the type.
+  if (BaseType.getTag() == dwarf::DW_TAG_reference_type ||
+      BaseType.getTag() == dwarf::DW_TAG_rvalue_reference_type)
+    return getSizeInBits();
+
+  if (BaseType.isDerivedType())
+    return DIDerivedType(BaseType).getOriginalTypeSize();
+
+  return BaseType.getSizeInBits();
+}
+
+/// getObjCProperty - Return property node, if this ivar is associated with one.
+MDNode *DIDerivedType::getObjCProperty() const {
+  if (DbgNode->getNumOperands() <= 10)
+    return NULL;
+  return dyn_cast_or_null<MDNode>(DbgNode->getOperand(10));
+}
+
+/// \brief Set the array of member DITypes.
+void DICompositeType::setTypeArray(DIArray Elements, DIArray TParams) {
+  assert((!TParams || DbgNode->getNumOperands() == 14) &&
+         "If you're setting the template parameters this should include a slot "
+         "for that!");
+  TrackingVH<MDNode> N(*this);
+  N->replaceOperandWith(10, Elements);
+  if (TParams)
+    N->replaceOperandWith(13, TParams);
+  DbgNode = N;
+}
+
+/// \brief Set the containing type.
+void DICompositeType::setContainingType(DICompositeType ContainingType) {
+  TrackingVH<MDNode> N(*this);
+  N->replaceOperandWith(12, ContainingType);
+  DbgNode = N;
+}
+
+/// isInlinedFnArgument - Return true if this variable provides debugging
+/// information for an inlined function arguments.
+bool DIVariable::isInlinedFnArgument(const Function *CurFn) {
+  assert(CurFn && "Invalid function");
+  if (!getContext().isSubprogram())
+    return false;
+  // This variable is not inlined function argument if its scope
+  // does not describe current function.
+  return !DISubprogram(getContext()).describes(CurFn);
+}
+
+/// describes - Return true if this subprogram provides debugging
+/// information for the function F.
+bool DISubprogram::describes(const Function *F) {
+  assert(F && "Invalid function");
+  if (F == getFunction())
+    return true;
+  StringRef Name = getLinkageName();
+  if (Name.empty())
+    Name = getName();
+  if (F->getName() == Name)
+    return true;
+  return false;
+}
+
+unsigned DISubprogram::isOptimized() const {
+  assert (DbgNode && "Invalid subprogram descriptor!");
+  if (DbgNode->getNumOperands() == 15)
+    return getUnsignedField(14);
+  return 0;
+}
+
+MDNode *DISubprogram::getVariablesNodes() const {
+  if (!DbgNode || DbgNode->getNumOperands() <= 18)
+    return NULL;
+  return dyn_cast_or_null<MDNode>(DbgNode->getOperand(18));
+}
+
+DIArray DISubprogram::getVariables() const {
+  if (!DbgNode || DbgNode->getNumOperands() <= 18)
+    return DIArray();
+  if (MDNode *T = dyn_cast_or_null<MDNode>(DbgNode->getOperand(18)))
+    return DIArray(T);
+  return DIArray();
+}
+
+Value *DITemplateValueParameter::getValue() const {
+  return getField(DbgNode, 4);
+}
+
+void DIScope::setFilename(StringRef Name, LLVMContext &Context) {
+  if (!DbgNode)
+    return;
+  MDString *MDName(MDString::get(Context, Name));
+  const_cast<MDNode*>(getNodeField(DbgNode, 1))->replaceOperandWith(0, MDName);
+}
+
+StringRef DIScope::getFilename() const {
+  if (!DbgNode)
+    return StringRef();
+  return ::getStringField(getNodeField(DbgNode, 1), 0);
+}
+
+StringRef DIScope::getDirectory() const {
+  if (!DbgNode)
+    return StringRef();
+  return ::getStringField(getNodeField(DbgNode, 1), 1);
+}
+
+DIArray DICompileUnit::getEnumTypes() const {
+  if (!DbgNode || DbgNode->getNumOperands() < 13)
+    return DIArray();
+
+  if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(7)))
+    return DIArray(N);
+  return DIArray();
+}
+
+DIArray DICompileUnit::getRetainedTypes() const {
+  if (!DbgNode || DbgNode->getNumOperands() < 13)
+    return DIArray();
+
+  if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(8)))
+    return DIArray(N);
+  return DIArray();
+}
+
+DIArray DICompileUnit::getSubprograms() const {
+  if (!DbgNode || DbgNode->getNumOperands() < 13)
+    return DIArray();
+
+  if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(9)))
+    return DIArray(N);
+  return DIArray();
+}
+
+
+DIArray DICompileUnit::getGlobalVariables() const {
+  if (!DbgNode || DbgNode->getNumOperands() < 13)
+    return DIArray();
+
+  if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(10)))
+    return DIArray(N);
+  return DIArray();
+}
+
+DIArray DICompileUnit::getImportedEntities() const {
+  if (!DbgNode || DbgNode->getNumOperands() < 13)
+    return DIArray();
+
+  if (MDNode *N = dyn_cast_or_null<MDNode>(DbgNode->getOperand(11)))
+    return DIArray(N);
+  return DIArray();
+}
+
+/// fixupObjcLikeName - Replace contains special characters used
+/// in a typical Objective-C names with '.' in a given string.
+static void fixupObjcLikeName(StringRef Str, SmallVectorImpl<char> &Out) {
+  bool isObjCLike = false;
+  for (size_t i = 0, e = Str.size(); i < e; ++i) {
+    char C = Str[i];
+    if (C == '[')
+      isObjCLike = true;
+
+    if (isObjCLike && (C == '[' || C == ']' || C == ' ' || C == ':' ||
+                       C == '+' || C == '(' || C == ')'))
+      Out.push_back('.');
+    else
+      Out.push_back(C);
+  }
+}
+
+/// getFnSpecificMDNode - Return a NameMDNode, if available, that is
+/// suitable to hold function specific information.
+NamedMDNode *llvm::getFnSpecificMDNode(const Module &M, DISubprogram Fn) {
+  SmallString<32> Name = StringRef("llvm.dbg.lv.");
+  StringRef FName = "fn";
+  if (Fn.getFunction())
+    FName = Fn.getFunction()->getName();
+  else
+    FName = Fn.getName();
+  char One = '\1';
+  if (FName.startswith(StringRef(&One, 1)))
+    FName = FName.substr(1);
+  fixupObjcLikeName(FName, Name);
+  return M.getNamedMetadata(Name.str());
+}
+
+/// getOrInsertFnSpecificMDNode - Return a NameMDNode that is suitable
+/// to hold function specific information.
+NamedMDNode *llvm::getOrInsertFnSpecificMDNode(Module &M, DISubprogram Fn) {
+  SmallString<32> Name = StringRef("llvm.dbg.lv.");
+  StringRef FName = "fn";
+  if (Fn.getFunction())
+    FName = Fn.getFunction()->getName();
+  else
+    FName = Fn.getName();
+  char One = '\1';
+  if (FName.startswith(StringRef(&One, 1)))
+    FName = FName.substr(1);
+  fixupObjcLikeName(FName, Name);
+
+  return M.getOrInsertNamedMetadata(Name.str());
+}
+
+/// createInlinedVariable - Create a new inlined variable based on current
+/// variable.
+/// @param DV            Current Variable.
+/// @param InlinedScope  Location at current variable is inlined.
+DIVariable llvm::createInlinedVariable(MDNode *DV, MDNode *InlinedScope,
+                                       LLVMContext &VMContext) {
+  SmallVector<Value *, 16> Elts;
+  // Insert inlined scope as 7th element.
+  for (unsigned i = 0, e = DV->getNumOperands(); i != e; ++i)
+    i == 7 ? Elts.push_back(InlinedScope) :
+             Elts.push_back(DV->getOperand(i));
+  return DIVariable(MDNode::get(VMContext, Elts));
+}
+
+/// cleanseInlinedVariable - Remove inlined scope from the variable.
+DIVariable llvm::cleanseInlinedVariable(MDNode *DV, LLVMContext &VMContext) {
+  SmallVector<Value *, 16> Elts;
+  // Insert inlined scope as 7th element.
+  for (unsigned i = 0, e = DV->getNumOperands(); i != e; ++i)
+    i == 7 ?
+      Elts.push_back(Constant::getNullValue(Type::getInt32Ty(VMContext))):
+      Elts.push_back(DV->getOperand(i));
+  return DIVariable(MDNode::get(VMContext, Elts));
+}
+
+/// getDISubprogram - Find subprogram that is enclosing this scope.
+DISubprogram llvm::getDISubprogram(const MDNode *Scope) {
+  DIDescriptor D(Scope);
+  if (D.isSubprogram())
+    return DISubprogram(Scope);
+
+  if (D.isLexicalBlockFile())
+    return getDISubprogram(DILexicalBlockFile(Scope).getContext());
+
+  if (D.isLexicalBlock())
+    return getDISubprogram(DILexicalBlock(Scope).getContext());
+
+  return DISubprogram();
+}
+
+/// getDICompositeType - Find underlying composite type.
+DICompositeType llvm::getDICompositeType(DIType T) {
+  if (T.isCompositeType())
+    return DICompositeType(T);
+
+  if (T.isDerivedType())
+    return getDICompositeType(DIDerivedType(T).getTypeDerivedFrom());
+
+  return DICompositeType();
+}
+
+/// isSubprogramContext - Return true if Context is either a subprogram
+/// or another context nested inside a subprogram.
+bool llvm::isSubprogramContext(const MDNode *Context) {
+  if (!Context)
+    return false;
+  DIDescriptor D(Context);
+  if (D.isSubprogram())
+    return true;
+  if (D.isType())
+    return isSubprogramContext(DIType(Context).getContext());
+  return false;
+}
+
+//===----------------------------------------------------------------------===//
+// DebugInfoFinder implementations.
+//===----------------------------------------------------------------------===//
+
+/// processModule - Process entire module and collect debug info.
+void DebugInfoFinder::processModule(const Module &M) {
+  if (NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu")) {
+    for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
+      DICompileUnit CU(CU_Nodes->getOperand(i));
+      addCompileUnit(CU);
+      DIArray GVs = CU.getGlobalVariables();
+      for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) {
+        DIGlobalVariable DIG(GVs.getElement(i));
+        if (addGlobalVariable(DIG))
+          processType(DIG.getType());
+      }
+      DIArray SPs = CU.getSubprograms();
+      for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
+        processSubprogram(DISubprogram(SPs.getElement(i)));
+      DIArray EnumTypes = CU.getEnumTypes();
+      for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
+        processType(DIType(EnumTypes.getElement(i)));
+      DIArray RetainedTypes = CU.getRetainedTypes();
+      for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i)
+        processType(DIType(RetainedTypes.getElement(i)));
+      // FIXME: We really shouldn't be bailing out after visiting just one CU
+      return;
+    }
+  }
+}
+
+/// processLocation - Process DILocation.
+void DebugInfoFinder::processLocation(DILocation Loc) {
+  if (!Loc.Verify()) return;
+  DIDescriptor S(Loc.getScope());
+  if (S.isCompileUnit())
+    addCompileUnit(DICompileUnit(S));
+  else if (S.isSubprogram())
+    processSubprogram(DISubprogram(S));
+  else if (S.isLexicalBlock())
+    processLexicalBlock(DILexicalBlock(S));
+  else if (S.isLexicalBlockFile()) {
+    DILexicalBlockFile DBF = DILexicalBlockFile(S);
+    processLexicalBlock(DILexicalBlock(DBF.getScope()));
+  }
+  processLocation(Loc.getOrigLocation());
+}
+
+/// processType - Process DIType.
+void DebugInfoFinder::processType(DIType DT) {
+  if (!addType(DT))
+    return;
+  if (DT.isCompositeType()) {
+    DICompositeType DCT(DT);
+    processType(DCT.getTypeDerivedFrom());
+    DIArray DA = DCT.getTypeArray();
+    for (unsigned i = 0, e = DA.getNumElements(); i != e; ++i) {
+      DIDescriptor D = DA.getElement(i);
+      if (D.isType())
+        processType(DIType(D));
+      else if (D.isSubprogram())
+        processSubprogram(DISubprogram(D));
+    }
+  } else if (DT.isDerivedType()) {
+    DIDerivedType DDT(DT);
+    processType(DDT.getTypeDerivedFrom());
+  }
+}
+
+/// processLexicalBlock
+void DebugInfoFinder::processLexicalBlock(DILexicalBlock LB) {
+  DIScope Context = LB.getContext();
+  if (Context.isLexicalBlock())
+    return processLexicalBlock(DILexicalBlock(Context));
+  else if (Context.isLexicalBlockFile()) {
+    DILexicalBlockFile DBF = DILexicalBlockFile(Context);
+    return processLexicalBlock(DILexicalBlock(DBF.getScope()));
+  }
+  else
+    return processSubprogram(DISubprogram(Context));
+}
+
+/// processSubprogram - Process DISubprogram.
+void DebugInfoFinder::processSubprogram(DISubprogram SP) {
+  if (!addSubprogram(SP))
+    return;
+  processType(SP.getType());
+}
+
+/// processDeclare - Process DbgDeclareInst.
+void DebugInfoFinder::processDeclare(const DbgDeclareInst *DDI) {
+  MDNode *N = dyn_cast<MDNode>(DDI->getVariable());
+  if (!N) return;
+
+  DIDescriptor DV(N);
+  if (!DV.isVariable())
+    return;
+
+  if (!NodesSeen.insert(DV))
+    return;
+  processType(DIVariable(N).getType());
+}
+
+/// addType - Add type into Tys.
+bool DebugInfoFinder::addType(DIType DT) {
+  if (!DT.isValid())
+    return false;
+
+  if (!NodesSeen.insert(DT))
+    return false;
+
+  TYs.push_back(DT);
+  return true;
+}
+
+/// addCompileUnit - Add compile unit into CUs.
+bool DebugInfoFinder::addCompileUnit(DICompileUnit CU) {
+  if (!CU.Verify())
+    return false;
+
+  if (!NodesSeen.insert(CU))
+    return false;
+
+  CUs.push_back(CU);
+  return true;
+}
+
+/// addGlobalVariable - Add global variable into GVs.
+bool DebugInfoFinder::addGlobalVariable(DIGlobalVariable DIG) {
+  if (!DIDescriptor(DIG).isGlobalVariable())
+    return false;
+
+  if (!NodesSeen.insert(DIG))
+    return false;
+
+  GVs.push_back(DIG);
+  return true;
+}
+
+// addSubprogram - Add subprgoram into SPs.
+bool DebugInfoFinder::addSubprogram(DISubprogram SP) {
+  if (!DIDescriptor(SP).isSubprogram())
+    return false;
+
+  if (!NodesSeen.insert(SP))
+    return false;
+
+  SPs.push_back(SP);
+  return true;
+}
+
+//===----------------------------------------------------------------------===//
+// DIDescriptor: dump routines for all descriptors.
+//===----------------------------------------------------------------------===//
+
+/// dump - Print descriptor to dbgs() with a newline.
+void DIDescriptor::dump() const {
+  print(dbgs()); dbgs() << '\n';
+}
+
+/// print - Print descriptor.
+void DIDescriptor::print(raw_ostream &OS) const {
+  if (!DbgNode) return;
+
+  if (const char *Tag = dwarf::TagString(getTag()))
+    OS << "[ " << Tag << " ]";
+
+  if (this->isSubrange()) {
+    DISubrange(DbgNode).printInternal(OS);
+  } else if (this->isCompileUnit()) {
+    DICompileUnit(DbgNode).printInternal(OS);
+  } else if (this->isFile()) {
+    DIFile(DbgNode).printInternal(OS);
+  } else if (this->isEnumerator()) {
+    DIEnumerator(DbgNode).printInternal(OS);
+  } else if (this->isBasicType()) {
+    DIType(DbgNode).printInternal(OS);
+  } else if (this->isDerivedType()) {
+    DIDerivedType(DbgNode).printInternal(OS);
+  } else if (this->isCompositeType()) {
+    DICompositeType(DbgNode).printInternal(OS);
+  } else if (this->isSubprogram()) {
+    DISubprogram(DbgNode).printInternal(OS);
+  } else if (this->isGlobalVariable()) {
+    DIGlobalVariable(DbgNode).printInternal(OS);
+  } else if (this->isVariable()) {
+    DIVariable(DbgNode).printInternal(OS);
+  } else if (this->isObjCProperty()) {
+    DIObjCProperty(DbgNode).printInternal(OS);
+  } else if (this->isNameSpace()) {
+    DINameSpace(DbgNode).printInternal(OS);
+  } else if (this->isScope()) {
+    DIScope(DbgNode).printInternal(OS);
+  }
+}
+
+void DISubrange::printInternal(raw_ostream &OS) const {
+  int64_t Count = getCount();
+  if (Count != -1)
+    OS << " [" << getLo() << ", " << Count - 1 << ']';
+  else
+    OS << " [unbounded]";
+}
+
+void DIScope::printInternal(raw_ostream &OS) const {
+  OS << " [" << getDirectory() << "/" << getFilename() << ']';
+}
+
+void DICompileUnit::printInternal(raw_ostream &OS) const {
+  DIScope::printInternal(OS);
+  OS << " [";
+  unsigned Lang = getLanguage();
+  if (const char *LangStr = dwarf::LanguageString(Lang))
+    OS << LangStr;
+  else
+    (OS << "lang 0x").write_hex(Lang);
+  OS << ']';
+}
+
+void DIEnumerator::printInternal(raw_ostream &OS) const {
+  OS << " [" << getName() << " :: " << getEnumValue() << ']';
+}
+
+void DIType::printInternal(raw_ostream &OS) const {
+  if (!DbgNode) return;
+
+  StringRef Res = getName();
+  if (!Res.empty())
+    OS << " [" << Res << "]";
+
+  // TODO: Print context?
+
+  OS << " [line " << getLineNumber()
+     << ", size " << getSizeInBits()
+     << ", align " << getAlignInBits()
+     << ", offset " << getOffsetInBits();
+  if (isBasicType())
+    if (const char *Enc =
+        dwarf::AttributeEncodingString(DIBasicType(DbgNode).getEncoding()))
+      OS << ", enc " << Enc;
+  OS << "]";
+
+  if (isPrivate())
+    OS << " [private]";
+  else if (isProtected())
+    OS << " [protected]";
+
+  if (isArtificial())
+    OS << " [artificial]";
+
+  if (isForwardDecl())
+    OS << " [fwd]";
+  if (isVector())
+    OS << " [vector]";
+  if (isStaticMember())
+    OS << " [static]";
+}
+
+void DIDerivedType::printInternal(raw_ostream &OS) const {
+  DIType::printInternal(OS);
+  OS << " [from " << getTypeDerivedFrom().getName() << ']';
+}
+
+void DICompositeType::printInternal(raw_ostream &OS) const {
+  DIType::printInternal(OS);
+  DIArray A = getTypeArray();
+  OS << " [" << A.getNumElements() << " elements]";
+}
+
+void DINameSpace::printInternal(raw_ostream &OS) const {
+  StringRef Name = getName();
+  if (!Name.empty())
+    OS << " [" << Name << ']';
+
+  OS << " [line " << getLineNumber() << ']';
+}
+
+void DISubprogram::printInternal(raw_ostream &OS) const {
+  // TODO : Print context
+  OS << " [line " << getLineNumber() << ']';
+
+  if (isLocalToUnit())
+    OS << " [local]";
+
+  if (isDefinition())
+    OS << " [def]";
+
+  if (getScopeLineNumber() != getLineNumber())
+    OS << " [scope " << getScopeLineNumber() << "]";
+
+  if (isPrivate())
+    OS << " [private]";
+  else if (isProtected())
+    OS << " [protected]";
+
+  StringRef Res = getName();
+  if (!Res.empty())
+    OS << " [" << Res << ']';
+}
+
+void DIGlobalVariable::printInternal(raw_ostream &OS) const {
+  StringRef Res = getName();
+  if (!Res.empty())
+    OS << " [" << Res << ']';
+
+  OS << " [line " << getLineNumber() << ']';
+
+  // TODO : Print context
+
+  if (isLocalToUnit())
+    OS << " [local]";
+
+  if (isDefinition())
+    OS << " [def]";
+}
+
+void DIVariable::printInternal(raw_ostream &OS) const {
+  StringRef Res = getName();
+  if (!Res.empty())
+    OS << " [" << Res << ']';
+
+  OS << " [line " << getLineNumber() << ']';
+}
+
+void DIObjCProperty::printInternal(raw_ostream &OS) const {
+  StringRef Name = getObjCPropertyName();
+  if (!Name.empty())
+    OS << " [" << Name << ']';
+
+  OS << " [line " << getLineNumber()
+     << ", properties " << getUnsignedField(6) << ']';
+}
+
+static void printDebugLoc(DebugLoc DL, raw_ostream &CommentOS,
+                          const LLVMContext &Ctx) {
+  if (!DL.isUnknown()) {          // Print source line info.
+    DIScope Scope(DL.getScope(Ctx));
+    // Omit the directory, because it's likely to be long and uninteresting.
+    if (Scope.Verify())
+      CommentOS << Scope.getFilename();
+    else
+      CommentOS << "<unknown>";
+    CommentOS << ':' << DL.getLine();
+    if (DL.getCol() != 0)
+      CommentOS << ':' << DL.getCol();
+    DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(DL.getInlinedAt(Ctx));
+    if (!InlinedAtDL.isUnknown()) {
+      CommentOS << " @[ ";
+      printDebugLoc(InlinedAtDL, CommentOS, Ctx);
+      CommentOS << " ]";
+    }
+  }
+}
+
+void DIVariable::printExtendedName(raw_ostream &OS) const {
+  const LLVMContext &Ctx = DbgNode->getContext();
+  StringRef Res = getName();
+  if (!Res.empty())
+    OS << Res << "," << getLineNumber();
+  if (MDNode *InlinedAt = getInlinedAt()) {
+    DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(InlinedAt);
+    if (!InlinedAtDL.isUnknown()) {
+      OS << " @[";
+      printDebugLoc(InlinedAtDL, OS, Ctx);
+      OS << "]";
+    }
+  }
+}