DebugInfo: Gut DIType and subclasses

Continuing PR23080, gut `DIType` and its various subclasses, leaving
behind thin wrappers around the pointer types in the new debug info
hierarchy.

llvm-svn: 235064
diff --git a/llvm/lib/IR/DIBuilder.cpp b/llvm/lib/IR/DIBuilder.cpp
index 49358d6..067a7ee 100644
--- a/llvm/lib/IR/DIBuilder.cpp
+++ b/llvm/lib/IR/DIBuilder.cpp
@@ -487,7 +487,7 @@
   auto *R =
       MDCompositeType::get(VMContext, dwarf::DW_TAG_array_type, "", nullptr, 0,
                            nullptr, MDTypeRef::get(Ty), Size, AlignInBits, 0,
-                           DIType::FlagVector, Subscripts, 0, nullptr);
+                           DebugNode::FlagVector, Subscripts, 0, nullptr);
   trackIfUnresolved(R);
   return R;
 }
@@ -501,27 +501,25 @@
 
 DIType DIBuilder::createArtificialType(DIType Ty) {
   // FIXME: Restrict this to the nodes where it's valid.
-  if (Ty.isArtificial())
+  if (Ty->isArtificial())
     return Ty;
-  return createTypeWithFlags(VMContext, Ty, DIType::FlagArtificial);
+  return createTypeWithFlags(VMContext, Ty, DebugNode::FlagArtificial);
 }
 
 DIType DIBuilder::createObjectPointerType(DIType Ty) {
   // FIXME: Restrict this to the nodes where it's valid.
-  if (Ty.isObjectPointer())
+  if (Ty->isObjectPointer())
     return Ty;
-  unsigned Flags = DIType::FlagObjectPointer | DIType::FlagArtificial;
+  unsigned Flags = DebugNode::FlagObjectPointer | DebugNode::FlagArtificial;
   return createTypeWithFlags(VMContext, Ty, Flags);
 }
 
 void DIBuilder::retainType(DIType T) {
-  assert(T.get() && "Expected non-null type");
+  assert(T && "Expected non-null type");
   AllRetainTypes.emplace_back(T);
 }
 
-DIBasicType DIBuilder::createUnspecifiedParameter() {
-  return DIBasicType();
-}
+DIBasicType DIBuilder::createUnspecifiedParameter() { return nullptr; }
 
 DICompositeType
 DIBuilder::createForwardDecl(unsigned Tag, StringRef Name, DIDescriptor Scope,
@@ -579,9 +577,9 @@
 
 static void checkGlobalVariableScope(DIDescriptor Context) {
 #ifndef NDEBUG
-  if (DICompositeType CT =
+  if (auto *CT =
           dyn_cast_or_null<MDCompositeType>(getNonCompileUnitScope(Context)))
-    assert(!CT.getIdentifier() &&
+    assert(CT->getIdentifier().empty() &&
            "Context of a global variable should not be a type with identifier");
 #endif
 }
@@ -675,11 +673,11 @@
                                        unsigned ScopeLine, unsigned Flags,
                                        bool isOptimized, Function *Fn,
                                        MDNode *TParams, MDNode *Decl) {
-  assert(Ty.getTag() == dwarf::DW_TAG_subroutine_type &&
+  assert(Ty->getTag() == dwarf::DW_TAG_subroutine_type &&
          "function types should be subroutines");
   auto *Node = MDSubprogram::get(
       VMContext, MDScopeRef::get(DIScope(getNonCompileUnitScope(Context))),
-      Name, LinkageName, File, LineNo, cast_or_null<MDSubroutineType>(Ty.get()),
+      Name, LinkageName, File, LineNo, cast_or_null<MDSubroutineType>(Ty),
       isLocalToUnit, isDefinition, ScopeLine, nullptr, 0, 0, Flags, isOptimized,
       Fn, cast_or_null<MDTuple>(TParams), cast_or_null<MDSubprogram>(Decl),
       MDTuple::getTemporary(VMContext, None).release());
@@ -701,11 +699,10 @@
   return MDSubprogram::getTemporary(
              VMContext,
              MDScopeRef::get(DIScope(getNonCompileUnitScope(Context))), Name,
-             LinkageName, File, LineNo,
-             cast_or_null<MDSubroutineType>(Ty.get()), isLocalToUnit,
-             isDefinition, ScopeLine, nullptr, 0, 0, Flags, isOptimized, Fn,
-             cast_or_null<MDTuple>(TParams), cast_or_null<MDSubprogram>(Decl),
-             nullptr)
+             LinkageName, File, LineNo, cast_or_null<MDSubroutineType>(Ty),
+             isLocalToUnit, isDefinition, ScopeLine, nullptr, 0, 0, Flags,
+             isOptimized, Fn, cast_or_null<MDTuple>(TParams),
+             cast_or_null<MDSubprogram>(Decl), nullptr)
       .release();
 }
 
@@ -717,7 +714,7 @@
                                      DIType VTableHolder, unsigned Flags,
                                      bool isOptimized, Function *Fn,
                                      MDNode *TParam) {
-  assert(Ty.getTag() == dwarf::DW_TAG_subroutine_type &&
+  assert(Ty->getTag() == dwarf::DW_TAG_subroutine_type &&
          "function types should be subroutines");
   assert(getNonCompileUnitScope(Context) &&
          "Methods should have both a Context and a context that isn't "
@@ -725,9 +722,9 @@
   // FIXME: Do we want to use different scope/lines?
   auto *SP = MDSubprogram::get(
       VMContext, MDScopeRef::get(cast<MDScope>(Context)), Name, LinkageName, F,
-      LineNo, cast_or_null<MDSubroutineType>(Ty.get()), isLocalToUnit,
-      isDefinition, LineNo, MDTypeRef::get(VTableHolder), VK, VIndex, Flags,
-      isOptimized, Fn, cast_or_null<MDTuple>(TParam), nullptr, nullptr);
+      LineNo, cast_or_null<MDSubroutineType>(Ty), isLocalToUnit, isDefinition,
+      LineNo, MDTypeRef::get(VTableHolder), VK, VIndex, Flags, isOptimized, Fn,
+      cast_or_null<MDTuple>(TParam), nullptr, nullptr);
 
   if (isDefinition)
     AllSubprograms.push_back(SP);