Until now all debug info MDNodes referred to a root MDNode, a compile unit. This simplified handling of these needs in dwarf writer. However, one side effect of this is that during link time optimization all these MDNodes are _not_ uniqued. In other words there will be N number of MDNodes describing "int", "char" and all other types, which would suddenly grow when each object file starts using libraries like STL.

MDNodes graph structure such that compiler unit keeps track of important MDNodes and update dwarf writer to process mdnodes top-down instead of bottom up.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137778 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 76 insertions, 46 deletions

diff --git a/lib/Analysis/DIBuilder.cpp b/lib/Analysis/DIBuilder.cpp
index 98a0ba085e..55f6fcab56 100644
--- a/lib/Analysis/DIBuilder.cpp
+++ b/lib/Analysis/DIBuilder.cpp
@@ -29,10 +29,30 @@ static Constant *GetTagConstant(LLVMContext &VMContext, unsigned Tag) {
 }
 
 DIBuilder::DIBuilder(Module &m)
-  : M(m), VMContext(M.getContext()), TheCU(0), DeclareFn(0), ValueFn(0) {}
+  : M(m), VMContext(M.getContext()), TheCU(0), TempEnumTypes(0), 
+    TempRetainTypes(0), TempSubprograms(0), TempGVs(0), DeclareFn(0), ValueFn(0)
+{}
 
 /// finalize - Construct any deferred debug info descriptors.
 void DIBuilder::finalize() {
+  DIArray Enums = getOrCreateArray(AllEnumTypes);
+  DIType(TempEnumTypes).replaceAllUsesWith(Enums);
+
+  DIArray RetainTypes = getOrCreateArray(AllRetainTypes);
+  DIType(TempRetainTypes).replaceAllUsesWith(RetainTypes);
+
+  DIArray SPs = getOrCreateArray(AllSubprograms);
+  DIType(TempSubprograms).replaceAllUsesWith(SPs);
+
+  DIArray GVs = getOrCreateArray(AllGVs);
+  DIType(TempGVs).replaceAllUsesWith(GVs);
+}
+
+/// getNonCompileUnitScope - If N is compile unit return NULL otherwise return N.
+static MDNode *getNonCompileUnitScope(MDNode *N) {
+  if (DIDescriptor(N).isCompileUnit())
+    return NULL;
+  return N;
 }
 
 /// createCompileUnit - A CompileUnit provides an anchor for all debugging
@@ -41,6 +61,23 @@ void DIBuilder::createCompileUnit(unsigned Lang, StringRef Filename,
                                   StringRef Directory, StringRef Producer, 
                                   bool isOptimized, StringRef Flags, 
                                   unsigned RunTimeVer) {
+  Value *TElts[] = { GetTagConstant(VMContext, DW_TAG_base_type) };
+  TempEnumTypes = MDNode::getTemporary(VMContext, TElts);
+  Value *THElts[] = { TempEnumTypes };
+  MDNode *EnumHolder = MDNode::get(VMContext, THElts);
+
+  TempRetainTypes = MDNode::getTemporary(VMContext, TElts);
+  Value *TRElts[] = { TempRetainTypes };
+  MDNode *RetainHolder = MDNode::get(VMContext, TRElts);
+
+  TempSubprograms = MDNode::getTemporary(VMContext, TElts);
+  Value *TSElts[] = { TempSubprograms };
+  MDNode *SPHolder = MDNode::get(VMContext, TSElts);
+
+  TempGVs = MDNode::getTemporary(VMContext, TElts);
+  Value *TVElts[] = { TempGVs };
+  MDNode *GVHolder = MDNode::get(VMContext, TVElts);
+
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_compile_unit),
     llvm::Constant::getNullValue(Type::getInt32Ty(VMContext)),
@@ -52,7 +89,11 @@ void DIBuilder::createCompileUnit(unsigned Lang, StringRef Filename,
     ConstantInt::get(Type::getInt1Ty(VMContext), true), // isMain
     ConstantInt::get(Type::getInt1Ty(VMContext), isOptimized),
     MDString::get(VMContext, Flags),
-    ConstantInt::get(Type::getInt32Ty(VMContext), RunTimeVer)
+    ConstantInt::get(Type::getInt32Ty(VMContext), RunTimeVer),
+    EnumHolder,
+    RetainHolder,
+    SPHolder,
+    GVHolder
   };
   TheCU = DICompileUnit(MDNode::get(VMContext, Elts));
 
@@ -69,7 +110,7 @@ DIFile DIBuilder::createFile(StringRef Filename, StringRef Directory) {
     GetTagConstant(VMContext, dwarf::DW_TAG_file_type),
     MDString::get(VMContext, Filename),
     MDString::get(VMContext, Directory),
-    TheCU
+    NULL // TheCU
   };
   return DIFile(MDNode::get(VMContext, Elts));
 }
@@ -93,7 +134,7 @@ DIType DIBuilder::createBasicType(StringRef Name, uint64_t SizeInBits,
   // offset and flags are always empty here.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_base_type),
-    TheCU,
+    NULL, //TheCU,
     MDString::get(VMContext, Name),
     NULL, // Filename
     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
@@ -112,7 +153,7 @@ DIType DIBuilder::createQualifiedType(unsigned Tag, DIType FromTy) {
   // Qualified types are encoded in DIDerivedType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, Tag),
-    TheCU,
+    NULL, //TheCU,
     MDString::get(VMContext, StringRef()), // Empty name.
     NULL, // Filename
     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
@@ -131,7 +172,7 @@ DIType DIBuilder::createPointerType(DIType PointeeTy, uint64_t SizeInBits,
   // Pointer types are encoded in DIDerivedType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_pointer_type),
-    TheCU,
+    NULL, //TheCU,
     MDString::get(VMContext, Name),
     NULL, // Filename
     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
@@ -149,7 +190,7 @@ DIType DIBuilder::createReferenceType(DIType RTy) {
   // References are encoded in DIDerivedType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_reference_type),
-    TheCU,
+    NULL, //TheCU,
     NULL, // Name
     NULL, // Filename
     ConstantInt::get(Type::getInt32Ty(VMContext), 0), // Line
@@ -169,7 +210,7 @@ DIType DIBuilder::createTypedef(DIType Ty, StringRef Name, DIFile File,
   assert(Ty.Verify() && "Invalid typedef type!");
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_typedef),
-    Context,
+    getNonCompileUnitScope(Context),
     MDString::get(VMContext, Name),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), LineNo),
@@ -231,7 +272,7 @@ DIType DIBuilder::createMemberType(DIDescriptor Scope, StringRef Name,
   // TAG_member is encoded in DIDerivedType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_member),
-    Scope,
+    getNonCompileUnitScope(Scope),
     MDString::get(VMContext, Name),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
@@ -256,7 +297,7 @@ DIType DIBuilder::createObjCIVar(StringRef Name,
   // TAG_member is encoded in DIDerivedType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_member),
-    File, // Or TheCU ? Ty ?
+    getNonCompileUnitScope(File),
     MDString::get(VMContext, Name),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
@@ -283,7 +324,7 @@ DIType DIBuilder::createClassType(DIDescriptor Context, StringRef Name,
  // TAG_class_type is encoded in DICompositeType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_class_type),
-    Context,
+    getNonCompileUnitScope(Context),
     MDString::get(VMContext, Name),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
@@ -308,7 +349,7 @@ DIBuilder::createTemplateTypeParameter(DIDescriptor Context, StringRef Name,
                                        unsigned ColumnNo) {
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_template_type_parameter),
-    Context,
+    getNonCompileUnitScope(Context),
     MDString::get(VMContext, Name),
     Ty,
     File,
@@ -327,7 +368,7 @@ DIBuilder::createTemplateValueParameter(DIDescriptor Context, StringRef Name,
                                         unsigned ColumnNo) {
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_template_value_parameter),
-    Context,
+    getNonCompileUnitScope(Context),
     MDString::get(VMContext, Name),
     Ty,
     ConstantInt::get(Type::getInt64Ty(VMContext), Val),
@@ -347,7 +388,7 @@ DIType DIBuilder::createStructType(DIDescriptor Context, StringRef Name,
  // TAG_structure_type is encoded in DICompositeType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_structure_type),
-    Context,
+    getNonCompileUnitScope(Context),
     MDString::get(VMContext, Name),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
@@ -372,7 +413,7 @@ DIType DIBuilder::createUnionType(DIDescriptor Scope, StringRef Name,
   // TAG_union_type is encoded in DICompositeType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_union_type),
-    Scope,
+    getNonCompileUnitScope(Scope),
     MDString::get(VMContext, Name),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
@@ -393,7 +434,7 @@ DIType DIBuilder::createSubroutineType(DIFile File, DIArray ParameterTypes) {
   // TAG_subroutine_type is encoded in DICompositeType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_subroutine_type),
-    File,
+    getNonCompileUnitScope(File),
     MDString::get(VMContext, ""),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
@@ -418,7 +459,7 @@ DIType DIBuilder::createEnumerationType(DIDescriptor Scope, StringRef Name,
   // TAG_enumeration_type is encoded in DICompositeType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_enumeration_type),
-    Scope,
+    getNonCompileUnitScope(Scope),
     MDString::get(VMContext, Name),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), LineNumber),
@@ -432,8 +473,7 @@ DIType DIBuilder::createEnumerationType(DIDescriptor Scope, StringRef Name,
     llvm::Constant::getNullValue(Type::getInt32Ty(VMContext)),
   };
   MDNode *Node = MDNode::get(VMContext, Elts);
-  NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.enum");
-  NMD->addOperand(Node);
+  AllEnumTypes.push_back(Node);
   return DIType(Node);
 }
 
@@ -443,9 +483,9 @@ DIType DIBuilder::createArrayType(uint64_t Size, uint64_t AlignInBits,
   // TAG_array_type is encoded in DICompositeType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_array_type),
-    TheCU,
+    NULL, //TheCU,
     MDString::get(VMContext, ""),
-    TheCU,
+    NULL, //TheCU,
     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
     ConstantInt::get(Type::getInt64Ty(VMContext), Size),
     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
@@ -465,9 +505,9 @@ DIType DIBuilder::createVectorType(uint64_t Size, uint64_t AlignInBits,
   // TAG_vector_type is encoded in DICompositeType format.
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_vector_type),
-    TheCU,
+    NULL, //TheCU,
     MDString::get(VMContext, ""),
-    TheCU,
+    NULL, //TheCU,
     ConstantInt::get(Type::getInt32Ty(VMContext), 0),
     ConstantInt::get(Type::getInt64Ty(VMContext), Size),
     ConstantInt::get(Type::getInt64Ty(VMContext), AlignInBits),
@@ -508,8 +548,7 @@ DIType DIBuilder::createArtificialType(DIType Ty) {
 /// retainType - Retain DIType in a module even if it is not referenced 
 /// through debug info anchors.
 void DIBuilder::retainType(DIType T) {
-  NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.ty");
-  NMD->addOperand(T);
+  AllRetainTypes.push_back(T);
 }
 
 /// createUnspecifiedParameter - Create unspeicified type descriptor
@@ -536,7 +575,7 @@ DIType DIBuilder::createTemporaryType(DIFile F) {
   // use here as long as DIType accepts it.
   Value *Elts[] = {
     GetTagConstant(VMContext, DW_TAG_base_type),
-    F.getCompileUnit(),
+    TheCU,
     NULL,
     F
   };
@@ -572,7 +611,7 @@ createGlobalVariable(StringRef Name, DIFile F, unsigned LineNumber,
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_variable),
     llvm::Constant::getNullValue(Type::getInt32Ty(VMContext)),
-    TheCU,
+    NULL, // TheCU,
     MDString::get(VMContext, Name),
     MDString::get(VMContext, Name),
     MDString::get(VMContext, Name),
@@ -584,9 +623,7 @@ createGlobalVariable(StringRef Name, DIFile F, unsigned LineNumber,
     Val
   };
   MDNode *Node = MDNode::get(VMContext, Elts);
-  // Create a named metadata so that we do not lose this mdnode.
-  NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.gv");
-  NMD->addOperand(Node);
+  AllGVs.push_back(Node);
   return DIGlobalVariable(Node);
 }
 
@@ -599,7 +636,7 @@ createStaticVariable(DIDescriptor Context, StringRef Name,
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_variable),
     llvm::Constant::getNullValue(Type::getInt32Ty(VMContext)),
-    Context,
+    getNonCompileUnitScope(Context),
     MDString::get(VMContext, Name),
     MDString::get(VMContext, Name),
     MDString::get(VMContext, LinkageName),
@@ -611,9 +648,7 @@ createStaticVariable(DIDescriptor Context, StringRef Name,
     Val
   };
   MDNode *Node = MDNode::get(VMContext, Elts);
-  // Create a named metadata so that we do not lose this mdnode.
-  NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.gv");
-  NMD->addOperand(Node);
+  AllGVs.push_back(Node);
   return DIGlobalVariable(Node);
 }
 
@@ -625,7 +660,7 @@ DIVariable DIBuilder::createLocalVariable(unsigned Tag, DIDescriptor Scope,
                                           unsigned ArgNo) {
   Value *Elts[] = {
     GetTagConstant(VMContext, Tag),
-    Scope,
+    getNonCompileUnitScope(Scope),
     MDString::get(VMContext, Name),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), (LineNo | (ArgNo << 24))),
@@ -660,7 +695,7 @@ DIVariable DIBuilder::createComplexVariable(unsigned Tag, DIDescriptor Scope,
                                             unsigned ArgNo) {
   SmallVector<Value *, 15> Elts;
   Elts.push_back(GetTagConstant(VMContext, Tag));
-  Elts.push_back(Scope);
+  Elts.push_back(getNonCompileUnitScope(Scope)),
   Elts.push_back(MDString::get(VMContext, Name));
   Elts.push_back(F);
   Elts.push_back(ConstantInt::get(Type::getInt32Ty(VMContext), (LineNo | (ArgNo << 24))));
@@ -686,7 +721,7 @@ DISubprogram DIBuilder::createFunction(DIDescriptor Context,
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_subprogram),
     llvm::Constant::getNullValue(Type::getInt32Ty(VMContext)),
-    Context,
+    getNonCompileUnitScope(Context),
     MDString::get(VMContext, Name),
     MDString::get(VMContext, Name),
     MDString::get(VMContext, LinkageName),
@@ -707,8 +742,7 @@ DISubprogram DIBuilder::createFunction(DIDescriptor Context,
   MDNode *Node = MDNode::get(VMContext, Elts);
 
   // Create a named metadata so that we do not lose this mdnode.
-  NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.sp");
-  NMD->addOperand(Node);
+  AllSubprograms.push_back(Node);
   return DISubprogram(Node);
 }
 
@@ -729,7 +763,7 @@ DISubprogram DIBuilder::createMethod(DIDescriptor Context,
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_subprogram),
     llvm::Constant::getNullValue(Type::getInt32Ty(VMContext)),
-    Context,
+    getNonCompileUnitScope(Context),
     MDString::get(VMContext, Name),
     MDString::get(VMContext, Name),
     MDString::get(VMContext, LinkageName),
@@ -747,10 +781,6 @@ DISubprogram DIBuilder::createMethod(DIDescriptor Context,
     TParam,
   };
   MDNode *Node = MDNode::get(VMContext, Elts);
-
-  // Create a named metadata so that we do not lose this mdnode.
-  NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.sp");
-  NMD->addOperand(Node);
   return DISubprogram(Node);
 }
 
@@ -760,7 +790,7 @@ DINameSpace DIBuilder::createNameSpace(DIDescriptor Scope, StringRef Name,
                                        DIFile File, unsigned LineNo) {
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_namespace),
-    Scope,
+    getNonCompileUnitScope(Scope),
     MDString::get(VMContext, Name),
     File,
     ConstantInt::get(Type::getInt32Ty(VMContext), LineNo)
@@ -774,7 +804,7 @@ DILexicalBlock DIBuilder::createLexicalBlock(DIDescriptor Scope, DIFile File,
   static unsigned int unique_id = 0;
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_lexical_block),
-    Scope,
+    getNonCompileUnitScope(Scope),
     ConstantInt::get(Type::getInt32Ty(VMContext), Line),
     ConstantInt::get(Type::getInt32Ty(VMContext), Col),
     File,