Add a field for arrays of unknown bound

The ABI tools do not diff the array length. They cannot distinguish
between arrays of unknown bound (e.g., int foo[]) and arrays of zero
length (e.g., int bar[0]). To implement array diff, this commit adds
"is_of_unknown_bound" field to the ABI dumps. It defaults to false so
that it can be omitted for common cases.

Test: ./test.py ; update prebuilts/clang-tools and build
Bug: 255702405
Change-Id: I5db163eb62e95fa01377ef7202e70cc2a0e89524

vndk/tools/header-checker/src/dumper/abi_wrappers.cpp

@@ -385,6 +385,7 @@ TypeAndCreationStatus ABIWrapper::SetTypeKind(
   }
   if (type_ptr->isArrayType()) {
     auto array_type_ir = std::make_unique<repr::ArrayTypeIR>();
+    array_type_ir->SetUnknownBound(type_ptr->isIncompleteArrayType());
     array_type_ir->SetSourceFile(source_file);
     return TypeAndCreationStatus(std::move(array_type_ir));
   }

vndk/tools/header-checker/src/repr/ir_representation.h

@@ -508,9 +508,18 @@ class EnumTypeIR : public TypeIR {
 
 class ArrayTypeIR : public TypeIR {
  public:
+  void SetUnknownBound(bool is_of_unknown_bound) {
+    is_of_unknown_bound_ = is_of_unknown_bound;
+  }
+
+  bool IsOfUnknownBound() const { return is_of_unknown_bound_; }
+
   LinkableMessageKind GetKind() const override {
     return LinkableMessageKind::ArrayTypeKind;
   }
+
+ private:
+  bool is_of_unknown_bound_ = false;
 };
 
 class PointerTypeIR : public TypeIR {

vndk/tools/header-checker/src/repr/ir_representation_internal.h

@@ -29,11 +29,6 @@ inline std::string GetReferencedTypeMapKey(T &element) {
   return element.GetReferencedType();
 }
 
-template <>
-inline std::string GetReferencedTypeMapKey<ArrayTypeIR>(ArrayTypeIR &element) {
-  return element.GetReferencedType() + ":" + std::to_string(element.GetSize());
-}
-
 template <>
 inline std::string GetReferencedTypeMapKey<BuiltinTypeIR>(
     BuiltinTypeIR &element) {
@@ -44,6 +39,12 @@ inline static std::string BoolToString(bool val) {
   return val ? "true" : "false";
 }
 
+template <>
+inline std::string GetReferencedTypeMapKey<ArrayTypeIR>(ArrayTypeIR &element) {
+  return element.GetReferencedType() + ":" + std::to_string(element.GetSize()) +
+         ":" + BoolToString(element.IsOfUnknownBound());
+}
+
 template <>
 inline std::string GetReferencedTypeMapKey<QualifiedTypeIR>(
     QualifiedTypeIR &element) {

vndk/tools/header-checker/src/repr/json/ir_dumper.cpp

@@ -265,6 +265,7 @@ IRToJsonConverter::ConvertBuiltinTypeIR(const BuiltinTypeIR *builtin_typep) {
 JsonObject
 IRToJsonConverter::ConvertArrayTypeIR(const ArrayTypeIR *array_typep) {
   JsonObject array_type;
+  array_type.Set("is_of_unknown_bound", array_typep->IsOfUnknownBound());
   AddTypeInfo(array_type, array_typep);
   return array_type;
 }

vndk/tools/header-checker/src/repr/json/ir_reader.cpp

@@ -355,6 +355,7 @@ void JsonIRReader::ReadArrayTypes(const JsonObjectRef &tu) {
   for (auto &&array_type : tu.GetObjects("array_types")) {
     ArrayTypeIR array_type_ir;
     ReadTypeInfo(array_type, &array_type_ir);
+    array_type_ir.SetUnknownBound(array_type.GetBool("is_of_unknown_bound"));
     module_->AddArrayType(std::move(array_type_ir));
   }
 }

vndk/tools/header-checker/src/repr/protobuf/ir_dumper.cpp

@@ -269,6 +269,7 @@ abi_dump::BuiltinType IRToProtobufConverter::ConvertBuiltinTypeIR(
 abi_dump::ArrayType IRToProtobufConverter::ConvertArrayTypeIR(
     const ArrayTypeIR *array_typep) {
   abi_dump::ArrayType added_array_type;
+  added_array_type.set_is_of_unknown_bound(array_typep->IsOfUnknownBound());
   if (!AddTypeInfo(added_array_type.mutable_type_info(), array_typep)) {
     llvm::errs() << "ArrayTypeIR could not be converted\n";
     ::exit(1);

vndk/tools/header-checker/src/repr/protobuf/ir_reader.cpp

@@ -245,6 +245,7 @@ void ProtobufIRReader::ReadArrayTypes(const abi_dump::TranslationUnit &tu) {
   for (auto &&array_type_protobuf : tu.array_types()) {
     ArrayTypeIR array_type_ir;
     ReadTypeInfo(array_type_protobuf.type_info(), &array_type_ir);
+    array_type_ir.SetUnknownBound(array_type_protobuf.is_of_unknown_bound());
     module_->AddArrayType(std::move(array_type_ir));
   }
 }

vndk/tools/header-checker/src/repr/protobuf/proto/abi_dump.proto

@@ -27,6 +27,7 @@ message BasicNamedAndTypedDecl {
 
 message ArrayType {
   optional BasicNamedAndTypedDecl type_info = 1;
+  optional bool is_of_unknown_bound = 2;
 }
 
 message PointerType {

vndk/tools/header-checker/tests/expected/example1.cpp

@@ -798,6 +798,7 @@ array_types {
     linker_set_key: "_ZTIA2_b"
     self_type: "_ZTIA2_b"
   }
+  is_of_unknown_bound: false
 }
 functions {
   return_type: "_ZTI4ListIfE"

vndk/tools/header-checker/tests/expected/example1.h

@@ -878,6 +878,7 @@ array_types {
     linker_set_key: "_ZTIA2_b"
     self_type: "_ZTIA2_b"
   }
+  is_of_unknown_bound: false
 }
 functions {
   return_type: "_ZTIi"

vndk/tools/header-checker/tests/expected/example2.h

@@ -355,6 +355,7 @@ array_types {
     linker_set_key: "_ZTIA2_b"
     self_type: "_ZTIA2_b"
   }
+  is_of_unknown_bound: false
 }
 functions {
   return_type: "_ZTIi"