[DI] Have createClassType create a class type. (#102624)

I was wondering why my use of createClassType was generating structure
reccords, and it turns out the code is wrong (or for some reason i don't
understand the intended use of the API).

clang itself does not use that part of the API, so this flew under the
radar.

Author: deadalnix

llvm/lib/IR/DIBuilder.cpp

@@ -509,7 +509,7 @@ DICompositeType *DIBuilder::createClassType(
          "createClassType should be called with a valid Context");
 
   auto *R = DICompositeType::get(
-      VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
+      VMContext, dwarf::DW_TAG_class_type, Name, File, LineNumber,
       getNonCompileUnitScope(Context), DerivedFrom, SizeInBits, AlignInBits,
       OffsetInBits, Flags, Elements, RunTimeLang, VTableHolder,
       cast_or_null<MDTuple>(TemplateParams), UniqueIdentifier);

llvm/unittests/IR/DebugInfoTest.cpp

@@ -1244,4 +1244,37 @@ TEST(DIBuilder, HashingDISubprogram) {
   EXPECT_EQ(HashDefinition, HashDefinitionAfter);
 }
 
+TEST(DIBuilder, CompositeTypes) {
+  LLVMContext Ctx;
+  std::unique_ptr<Module> M = std::make_unique<Module>("MyModule", Ctx);
+  DIBuilder DIB(*M);
+
+  DIFile *F = DIB.createFile("main.c", "/");
+  DICompileUnit *CU =
+      DIB.createCompileUnit(dwarf::DW_LANG_C, F, "Test", false, "", 0);
+
+  DICompositeType *Class =
+      DIB.createClassType(CU, "MyClass", F, 0, 8, 8, 0, {}, nullptr, {}, 0,
+                          nullptr, nullptr, "ClassUniqueIdentifier");
+  EXPECT_EQ(Class->getTag(), dwarf::DW_TAG_class_type);
+
+  DICompositeType *Struct = DIB.createStructType(
+      CU, "MyStruct", F, 0, 8, 8, {}, {}, {}, 0, {}, "StructUniqueIdentifier");
+  EXPECT_EQ(Struct->getTag(), dwarf::DW_TAG_structure_type);
+
+  DICompositeType *Union = DIB.createUnionType(CU, "MyUnion", F, 0, 8, 8, {},
+                                               {}, 0, "UnionUniqueIdentifier");
+  EXPECT_EQ(Union->getTag(), dwarf::DW_TAG_union_type);
+
+  DICompositeType *Array = DIB.createArrayType(8, 8, nullptr, {});
+  EXPECT_EQ(Array->getTag(), dwarf::DW_TAG_array_type);
+
+  DICompositeType *Vector = DIB.createVectorType(8, 8, nullptr, {});
+  EXPECT_EQ(Vector->getTag(), dwarf::DW_TAG_array_type);
+
+  DICompositeType *Enum = DIB.createEnumerationType(
+      CU, "MyEnum", F, 0, 8, 8, {}, nullptr, 0, "EnumUniqueIdentifier");
+  EXPECT_EQ(Enum->getTag(), dwarf::DW_TAG_enumeration_type);
+}
+
 } // end namespace