Add support for record attributes to ijar

See https://docs.oracle.com/javase/specs/jvms/se17/html/jvms-4.html#jvms-4.7.30

#13965

PiperOrigin-RevId: 400755863

third_party/ijar/classfile.cc

@@ -438,6 +438,25 @@ struct KeepForCompileAttribute : Attribute {
   void Write(u1 *&p) { WriteProlog(p, 0); }
 };
 
+struct HasAttrs {
+  std::vector<Attribute*> attributes;
+
+  void WriteAttrs(u1 *&p);
+  void ReadAttrs(const u1 *&p);
+
+  virtual ~HasAttrs() {
+    for (const auto *attribute : attributes) {
+      delete attribute;
+    }
+  }
+
+  void ExtractClassNames() {
+    for (auto *attribute : attributes) {
+      attribute->ExtractClassNames();
+    }
+  }
+};
+
 // See sec.4.7.5 of JVM spec.
 struct ExceptionsAttribute : Attribute {
 
@@ -1234,6 +1253,55 @@ struct NestMembersAttribute : Attribute {
   std::vector<Constant *> classes_;
 };
 
+// See JVMS §4.7.30
+struct RecordAttribute : Attribute {
+  static RecordAttribute *Read(const u1 *&p, Constant *attribute_name,
+                                    u4 attribute_length) {
+    auto attr = new RecordAttribute;
+    attr->attribute_name_ = attribute_name;
+    attr->attribute_length_ = attribute_length;
+    u2 components_length = get_u2be(p);
+    for (int i = 0; i < components_length; ++i) {
+      attr->components_.push_back(RecordComponentInfo::Read(p));
+    }
+    return attr;
+  }
+
+  void Write(u1 *&p) {
+    u1 *tmp = new u1[attribute_length_];
+    u1 *start = tmp;
+    put_u2be(tmp, components_.size());
+    for (size_t i = 0; i < components_.size(); ++i) {
+      components_[i]->Write(tmp);
+    }
+    u2 length = tmp - start;
+    WriteProlog(p, length);
+    memcpy(p, start, length);
+    p += length;
+  }
+
+  struct RecordComponentInfo : HasAttrs {
+    void Write(u1 *&p) {
+      put_u2be(p, name_->slot());
+      put_u2be(p, descriptor_->slot());
+      WriteAttrs(p);
+    }
+    static RecordComponentInfo *Read(const u1 *&p) {
+      RecordComponentInfo *value = new RecordComponentInfo;
+      value->name_ = constant(get_u2be(p));
+      value->descriptor_ = constant(get_u2be(p));
+      value->ReadAttrs(p);
+      return value;
+    }
+
+    Constant *name_;
+    Constant *descriptor_;
+  };
+
+  u4 attribute_length_;
+  std::vector<RecordComponentInfo *> components_;
+};
+
 struct GeneralAttribute : Attribute {
   static GeneralAttribute* Read(const u1 *&p, Constant *attribute_name,
                                 u4 attribute_length) {
@@ -1260,25 +1328,6 @@ struct GeneralAttribute : Attribute {
  *                                                                    *
  **********************************************************************/
 
-struct HasAttrs {
-  std::vector<Attribute*> attributes;
-
-  void WriteAttrs(u1 *&p);
-  void ReadAttrs(const u1 *&p);
-
-  virtual ~HasAttrs() {
-    for (const auto *attribute : attributes) {
-      delete attribute;
-    }
-  }
-
-  void ExtractClassNames() {
-    for (auto *attribute : attributes) {
-      attribute->ExtractClassNames();
-    }
-  }
-};
-
 // A field or method.
 // See sec.4.5 and 4.6 of JVM spec.
 struct Member : HasAttrs {
@@ -1451,6 +1500,9 @@ void HasAttrs::ReadAttrs(const u1 *&p) {
     } else if (attr_name == "NestMembers") {
       attributes.push_back(
           NestMembersAttribute::Read(p, attribute_name, attribute_length));
+    } else if (attr_name == "Record") {
+      attributes.push_back(
+          RecordAttribute::Read(p, attribute_name, attribute_length));
     } else if (attr_name == "com.google.devtools.ijar.KeepForCompile") {
       auto attr = new KeepForCompileAttribute;
       attr->attribute_name_ = attribute_name;

third_party/ijar/test/BUILD

@@ -34,6 +34,7 @@ sh_test(
         # This is a precompiled .jar file because it needs to be compiled with JDK 11.
         # TODO(cushon): build from source once we have a JDK 11
         "nestmates/nestmates.jar",
+        "records/records.jar",
         ":source_debug_extension.jar",
         ":keep_for_compile_lib.jar",
         ":largest_regular.jar",

third_party/ijar/test/ijar_test.sh

@@ -77,6 +77,8 @@ METHODPARAM_JAR=$IJAR_SRCDIR/test/libmethodparameters.jar
 METHODPARAM_IJAR=$TEST_TMPDIR/methodparameters_interface.jar
 NESTMATES_JAR=$IJAR_SRCDIR/test/nestmates/nestmates.jar
 NESTMATES_IJAR=$TEST_TMPDIR/nestmates_interface.jar
+RECORDS_JAR=$IJAR_SRCDIR/test/records/records.jar
+RECORDS_IJAR=$TEST_TMPDIR/records_interface.jar
 SOURCEDEBUGEXT_JAR=$IJAR_SRCDIR/test/source_debug_extension.jar
 SOURCEDEBUGEXT_IJAR=$TEST_TMPDIR/source_debug_extension.jar
 CENTRAL_DIR_LARGEST_REGULAR=$IJAR_SRCDIR/test/largest_regular.jar
@@ -532,6 +534,17 @@ function test_nestmates_attribute() {
   expect_log "NestHost" "NestHost not preserved!"
 }
 
+function test_records_attribute() {
+  ls $IJAR $RECORDS_JAR
+
+  # Check that Java 16 Records attributes are preserved
+  $IJAR $RECORDS_JAR $RECORDS_IJAR || fail "ijar failed"
+
+  $JAVAP -classpath $RECORDS_IJAR -v RecordTest >& $TEST_log \
+    || fail "javap failed"
+  expect_log "Record" "Records not preserved!"
+}
+
 function test_source_debug_extension_attribute() {
   # Check that SourceDebugExtension attributes are dropped without a warning
   $IJAR $SOURCEDEBUGEXT_JAR $SOURCEDEBUGEXT_IJAR >& $TEST_log || fail "ijar failed"

third_party/ijar/test/records/RecordTest.java

@@ -0,0 +1,19 @@
+// Copyright 2021 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+import java.util.List;
+import java.util.Map;
+
+/** A class that results in record attributes in Java 16. */
+public record RecordTest(List<String> foo, Map<String, Integer> bar) {}