Remove Primitive::Kind::Incomplete

Author: ttreyer

oi/type_graph/DrgnParser.cpp

@@ -123,10 +123,17 @@ Type& DrgnParser::enumerateType(struct drgn_type* type) {
                               std::to_string(kind)};
     }
   } catch (const DrgnParserError& e) {
+    depth_--;
     if (isTypeIncomplete) {
-      t = &makeType<Primitive>(type, Primitive::Kind::Incomplete);
+      const char* typeName = "<incomplete>";
+      if (drgn_type_has_name(type)) {
+        typeName = drgn_type_name(type);
+      } else if (drgn_type_has_tag(type)) {
+        typeName = drgn_type_tag(type);
+      }
+
+      return makeType<Incomplete>(nullptr, typeName);
     } else {
-      depth_--;
       throw e;
     }
   }

oi/type_graph/EnforceCompatibility.cpp

@@ -83,14 +83,6 @@ void EnforceCompatibility::visit(Class& c) {
         // the pointer's address in this case.
         return true;
       }
-
-      if (auto* primitive = dynamic_cast<Primitive*>(&ptr->pointeeType())) {
-        if (primitive->kind() == Primitive::Kind::Incomplete) {
-          // This is a pointer to an incomplete type. CodeGen v1 does not record
-          // the pointer's address in this case.
-          return true;
-        }
-      }
     }
 
     return false;

oi/type_graph/Flattener.cpp

@@ -56,9 +56,7 @@ void flattenParent(const Parent& parent,
     // Create a new member to represent this parent container
     flattenedMembers.emplace_back(*parentContainer, Flattener::ParentPrefix,
                                   parent.bitOffset);
-  } else if (auto* parentPrimitive = dynamic_cast<Primitive*>(&parentType);
-             parentPrimitive &&
-             parentPrimitive->kind() == Primitive::Kind::Incomplete) {
+  } else if (auto* parentPrimitive = dynamic_cast<Incomplete*>(&parentType)) {
     // Bad DWARF can lead to us seeing incomplete parent types. Just ignore
     // these as there is nothing we can do to recover the missing info.
   } else {

oi/type_graph/Printer.cpp

@@ -38,8 +38,13 @@ void Printer::print(const Type& type) {
 
 void Printer::visit(const Incomplete& i) {
   prefix();
-  out_ << "Incomplete:" << std::endl;
-  print(i.underlyingType());
+  out_ << "Incomplete";
+  if (auto underlyingType = i.underlyingType()) {
+    out_ << std::endl;
+    print(underlyingType.value().get());
+  } else {
+    out_ << ": [" << i.inputName() << "]" << std::endl;
+  }
 }
 
 void Printer::visit(const Class& c) {
@@ -97,10 +102,7 @@ void Printer::visit(const Container& c) {
 
 void Printer::visit(const Primitive& p) {
   prefix();
-  out_ << "Primitive: " << p.name();
-  if (p.kind() == Primitive::Kind::Incomplete)
-    out_ << " (incomplete)";
-  out_ << std::endl;
+  out_ << "Primitive: " << p.name() << std::endl;
 }
 
 void Printer::visit(const Enum& e) {

oi/type_graph/TypeGraph.cpp

@@ -65,9 +65,6 @@ Primitive& TypeGraph::makeType<Primitive>(Primitive::Kind kind) {
     case Primitive::Kind::Void:
       static Primitive pVoid{kind};
       return pVoid;
-    case Primitive::Kind::Incomplete:
-      static Primitive pIncomplete{kind};
-      return pIncomplete;
   }
 }
 

oi/type_graph/Types.cpp

@@ -62,7 +62,6 @@ std::string Primitive::getName(Kind kind) {
     case Kind::StubbedPointer:
       return "StubbedPointer";
     case Kind::Void:
-    case Kind::Incomplete:
       return "void";
   }
 }
@@ -105,7 +104,6 @@ std::size_t Primitive::size() const {
     case Kind::StubbedPointer:
       return sizeof(uintptr_t);
     case Kind::Void:
-    case Kind::Incomplete:
       return 0;
   }
 }

oi/type_graph/Types.h

@@ -34,6 +34,7 @@
 #include <optional>
 #include <string>
 #include <string_view>
+#include <variant>
 #include <vector>
 
 #include "oi/ContainerInfo.h"
@@ -195,6 +196,10 @@ class Incomplete : public Type {
   Incomplete(Type& underlyingType) : underlyingType_(underlyingType) {
   }
 
+  Incomplete(std::string underlyingTypeName)
+      : underlyingType_(std::move(underlyingTypeName)) {
+  }
+
   static inline constexpr bool has_node_id = false;
 
   DECLARE_ACCEPT
@@ -204,7 +209,13 @@ class Incomplete : public Type {
   }
 
   std::string_view inputName() const override {
-    return underlyingType_.inputName();
+    if (std::holds_alternative<std::string>(underlyingType_)) {
+      return std::get<std::string>(underlyingType_);
+    }
+
+    return std::get<std::reference_wrapper<Type>>(underlyingType_)
+        .get()
+        .inputName();
   }
 
   size_t size() const override {
@@ -219,12 +230,16 @@ class Incomplete : public Type {
     return -1;
   }
 
-  Type& underlyingType() const {
-    return underlyingType_;
+  std::optional<std::reference_wrapper<Type>> underlyingType() const {
+    if (std::holds_alternative<std::string>(underlyingType_)) {
+      return std::nullopt;
+    }
+
+    return std::get<std::reference_wrapper<Type>>(underlyingType_);
   }
 
  private:
-  Type& underlyingType_;
+  std::variant<std::string, std::reference_wrapper<Type>> underlyingType_;
   static const std::string kName;
 };
 
@@ -551,8 +566,6 @@ class Primitive : public Type {
 
     StubbedPointer,
     Void,
-    Incomplete,  // Behaves the same as Void, but alerts us that the type was
-                 // stubbed out due to incomplete DWARF
   };
 
   explicit Primitive(Kind kind) : kind_(kind), name_(getName(kind)) {

test/TypeGraphParser.cpp

@@ -49,8 +49,6 @@ Primitive::Kind getKind(std::string_view kindStr) {
     return Primitive::Kind::StubbedPointer;
   if (kindStr == "void")
     return Primitive::Kind::Void;
-  if (kindStr == "void (incomplete)")
-    return Primitive::Kind::Incomplete;
   throw TypeGraphParserError{"Invalid Primitive::Kind: " +
                              std::string{kindStr}};
 }
@@ -212,8 +210,16 @@ Type& TypeGraphParser::parseType(std::string_view& input, size_t rootIndent) {
 
     type = &it->second.get();
   } else if (nodeTypeName == "Incomplete") {
-    auto& underlyingType = parseType(input, indent + 2);
-    type = &typeGraph_.makeType<Incomplete>(underlyingType);
+    if (line[nodeEndPos] == ':') {
+      auto nameStartPos = line.find('[', nodeEndPos) + 1;
+      auto nameEndPos = line.find(']', nameStartPos);
+      auto underlyingTypeName =
+          line.substr(nameStartPos, nameEndPos - nameStartPos);
+      type = &typeGraph_.makeType<Incomplete>(std::string(underlyingTypeName));
+    } else {
+      auto& underlyingType = parseType(input, indent + 2);
+      type = &typeGraph_.makeType<Incomplete>(underlyingType);
+    }
   } else if (nodeTypeName == "Class" || nodeTypeName == "Struct" ||
              nodeTypeName == "Union") {
     // Format: "Class: MyClass (size: 12)"

test/test_drgn_parser.cpp

@@ -367,8 +367,7 @@ TEST_F(DrgnParserTest, PointerNoFollow) {
 TEST_F(DrgnParserTest, PointerIncomplete) {
   test("oid_test_case_pointers_incomplete_raw", R"(
 [0] Pointer
-      Incomplete:
-        Primitive: void (incomplete)
+      Incomplete: [IncompleteType]
 )");
 }
 

test/test_enforce_compatibility.cpp

@@ -36,7 +36,8 @@ TEST(EnforceCompatibilityTest, VoidPointer) {
 [0] Class: MyClass (size: 8)
       Member: p (offset: 0)
 [1]     Pointer
-          Primitive: void (incomplete)
+          Incomplete
+            Primitive: void
 )",
        R"(
 [0] Class: MyClass (size: 8)