7109878: The instanceKlass EnclosingMethhod attribute fields can be folded into the _inner_class field.

Summary: Fold instanceKlass::_enclosing_method_class_index and instanceKlass::_enclosing_method_method_index into the instanceKlass::_inner_classes array.
Reviewed-by: never, coleenp
Contributed-by: Jiangli Zhou <jiangli.zhou@oracle.com>

3 files changed, 48 insertions, 72 deletions

diff --git a/src/share/vm/prims/jvm.cpp b/src/share/vm/prims/jvm.cpp
index 4c503fea3..3f097819e 100644
--- a/src/share/vm/prims/jvm.cpp
+++ b/src/share/vm/prims/jvm.cpp
@@ -1301,9 +1301,6 @@ JVM_END
 // Inner class reflection ///////////////////////////////////////////////////////////////////////////////
 
 JVM_ENTRY(jobjectArray, JVM_GetDeclaredClasses(JNIEnv *env, jclass ofClass))
-  const int inner_class_info_index = 0;
-  const int outer_class_info_index = 1;
-
   JvmtiVMObjectAllocEventCollector oam;
   // ofClass is a reference to a java_lang_Class object. The mirror object
   // of an instanceKlass
@@ -1315,26 +1312,26 @@ JVM_ENTRY(jobjectArray, JVM_GetDeclaredClasses(JNIEnv *env, jclass ofClass))
   }
 
   instanceKlassHandle k(thread, java_lang_Class::as_klassOop(JNIHandles::resolve_non_null(ofClass)));
+  InnerClassesIterator iter(k);
 
-  if (k->inner_classes()->length() == 0) {
+  if (iter.length() == 0) {
     // Neither an inner nor outer class
     oop result = oopFactory::new_objArray(SystemDictionary::Class_klass(), 0, CHECK_NULL);
     return (jobjectArray)JNIHandles::make_local(env, result);
   }
 
   // find inner class info
-  typeArrayHandle    icls(thread, k->inner_classes());
   constantPoolHandle cp(thread, k->constants());
-  int length = icls->length();
+  int length = iter.length();
 
   // Allocate temp. result array
   objArrayOop r = oopFactory::new_objArray(SystemDictionary::Class_klass(), length/4, CHECK_NULL);
   objArrayHandle result (THREAD, r);
   int members = 0;
 
-  for(int i = 0; i < length; i += 4) {
-    int ioff = icls->ushort_at(i + inner_class_info_index);
-    int ooff = icls->ushort_at(i + outer_class_info_index);
+  for (; !iter.done(); iter.next()) {
+    int ioff = iter.inner_class_info_index();
+    int ooff = iter.outer_class_info_index();
 
     if (ioff != 0 && ooff != 0) {
       // Check to see if the name matches the class we're looking for
@@ -1392,17 +1389,13 @@ klassOop instanceKlass::compute_enclosing_class_impl(instanceKlassHandle k,
                                                      bool* inner_is_member,
                                                      TRAPS) {
   Thread* thread = THREAD;
-  const int inner_class_info_index = inner_class_inner_class_info_offset;
-  const int outer_class_info_index = inner_class_outer_class_info_offset;
-
-  if (k->inner_classes()->length() == 0) {
+  InnerClassesIterator iter(k);
+  if (iter.length() == 0) {
     // No inner class info => no declaring class
     return NULL;
   }
 
-  typeArrayHandle i_icls(thread, k->inner_classes());
   constantPoolHandle i_cp(thread, k->constants());
-  int i_length = i_icls->length();
 
   bool found = false;
   klassOop ok;
@@ -1410,10 +1403,10 @@ klassOop instanceKlass::compute_enclosing_class_impl(instanceKlassHandle k,
   *inner_is_member = false;
 
   // Find inner_klass attribute
-  for (int i = 0; i < i_length && !found; i += inner_class_next_offset) {
-    int ioff = i_icls->ushort_at(i + inner_class_info_index);
-    int ooff = i_icls->ushort_at(i + outer_class_info_index);
-    int noff = i_icls->ushort_at(i + inner_class_inner_name_offset);
+  for (; !iter.done() && !found; iter.next()) {
+    int ioff = iter.inner_class_info_index();
+    int ooff = iter.outer_class_info_index();
+    int noff = iter.inner_name_index();
     if (ioff != 0) {
       // Check to see if the name matches the class we're looking for
       // before attempting to find the class.
diff --git a/src/share/vm/prims/jvmtiClassFileReconstituter.cpp b/src/share/vm/prims/jvmtiClassFileReconstituter.cpp
index af576eb28..d7dfea5a9 100644
--- a/src/share/vm/prims/jvmtiClassFileReconstituter.cpp
+++ b/src/share/vm/prims/jvmtiClassFileReconstituter.cpp
@@ -292,8 +292,8 @@ void JvmtiClassFileReconstituter::write_signature_attribute(u2 generic_signature
 
 // Compute the number of entries in the InnerClasses attribute
 u2 JvmtiClassFileReconstituter::inner_classes_attribute_length() {
-  typeArrayOop inner_class_list = ikh()->inner_classes();
-  return (inner_class_list == NULL) ? 0 : inner_class_list->length();
+  InnerClassesIterator iter(ikh());
+  return iter.length();
 }
 
 // Write an annotation attribute.  The VM stores them in raw form, so all we need
@@ -324,26 +324,20 @@ void JvmtiClassFileReconstituter::write_annotations_attribute(const char* attr_n
 // JVMSpec|     } classes[number_of_classes];
 // JVMSpec|   }
 void JvmtiClassFileReconstituter::write_inner_classes_attribute(int length) {
-  typeArrayOop inner_class_list = ikh()->inner_classes();
-  guarantee(inner_class_list != NULL && inner_class_list->length() == length,
+  InnerClassesIterator iter(ikh());
+  guarantee(iter.length() != 0 && iter.length() == length,
             "caller must check");
-  typeArrayHandle inner_class_list_h(thread(), inner_class_list);
-  assert (length % instanceKlass::inner_class_next_offset == 0, "just checking");
   u2 entry_count = length / instanceKlass::inner_class_next_offset;
   u4 size = 2 + entry_count * (2+2+2+2);
 
   write_attribute_name_index("InnerClasses");
   write_u4(size);
   write_u2(entry_count);
-  for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) {
-    write_u2(inner_class_list_h->ushort_at(
-                      i + instanceKlass::inner_class_inner_class_info_offset));
-    write_u2(inner_class_list_h->ushort_at(
-                      i + instanceKlass::inner_class_outer_class_info_offset));
-    write_u2(inner_class_list_h->ushort_at(
-                      i + instanceKlass::inner_class_inner_name_offset));
-    write_u2(inner_class_list_h->ushort_at(
-                      i + instanceKlass::inner_class_access_flags_offset));
+  for (; !iter.done(); iter.next()) {
+    write_u2(iter.inner_class_info_index());
+    write_u2(iter.outer_class_info_index());
+    write_u2(iter.inner_name_index());
+    write_u2(iter.inner_access_flags());
   }
 }
 
diff --git a/src/share/vm/prims/jvmtiRedefineClasses.cpp b/src/share/vm/prims/jvmtiRedefineClasses.cpp
index 295ed8664..2caecf680 100644
--- a/src/share/vm/prims/jvmtiRedefineClasses.cpp
+++ b/src/share/vm/prims/jvmtiRedefineClasses.cpp
@@ -2400,44 +2400,33 @@ void VM_RedefineClasses::set_new_constant_pool(
   // new constant indices as needed. The inner classes info is a
   // quadruple:
   // (inner_class_info, outer_class_info, inner_name, inner_access_flags)
-  typeArrayOop inner_class_list = scratch_class->inner_classes();
-  int icl_length = (inner_class_list == NULL) ? 0 : inner_class_list->length();
-  if (icl_length > 0) {
-    typeArrayHandle inner_class_list_h(THREAD, inner_class_list);
-    for (int i = 0; i < icl_length;
-         i += instanceKlass::inner_class_next_offset) {
-      int cur_index = inner_class_list_h->ushort_at(i
-                        + instanceKlass::inner_class_inner_class_info_offset);
-      if (cur_index == 0) {
-        continue;  // JVM spec. allows null inner class refs so skip it
-      }
-      int new_index = find_new_index(cur_index);
-      if (new_index != 0) {
-        RC_TRACE_WITH_THREAD(0x00080000, THREAD,
-          ("inner_class_info change: %d to %d", cur_index, new_index));
-        inner_class_list_h->ushort_at_put(i
-          + instanceKlass::inner_class_inner_class_info_offset, new_index);
-      }
-      cur_index = inner_class_list_h->ushort_at(i
-                    + instanceKlass::inner_class_outer_class_info_offset);
-      new_index = find_new_index(cur_index);
-      if (new_index != 0) {
-        RC_TRACE_WITH_THREAD(0x00080000, THREAD,
-          ("outer_class_info change: %d to %d", cur_index, new_index));
-        inner_class_list_h->ushort_at_put(i
-          + instanceKlass::inner_class_outer_class_info_offset, new_index);
-      }
-      cur_index = inner_class_list_h->ushort_at(i
-                    + instanceKlass::inner_class_inner_name_offset);
-      new_index = find_new_index(cur_index);
-      if (new_index != 0) {
-        RC_TRACE_WITH_THREAD(0x00080000, THREAD,
-          ("inner_name change: %d to %d", cur_index, new_index));
-        inner_class_list_h->ushort_at_put(i
-          + instanceKlass::inner_class_inner_name_offset, new_index);
-      }
-    } // end for each inner class
-  } // end if we have inner classes
+  InnerClassesIterator iter(scratch_class);
+  for (; !iter.done(); iter.next()) {
+    int cur_index = iter.inner_class_info_index();
+    if (cur_index == 0) {
+      continue;  // JVM spec. allows null inner class refs so skip it
+    }
+    int new_index = find_new_index(cur_index);
+    if (new_index != 0) {
+      RC_TRACE_WITH_THREAD(0x00080000, THREAD,
+        ("inner_class_info change: %d to %d", cur_index, new_index));
+      iter.set_inner_class_info_index(new_index);
+    }
+    cur_index = iter.outer_class_info_index();
+    new_index = find_new_index(cur_index);
+    if (new_index != 0) {
+      RC_TRACE_WITH_THREAD(0x00080000, THREAD,
+        ("outer_class_info change: %d to %d", cur_index, new_index));
+      iter.set_outer_class_info_index(new_index);
+    }
+    cur_index = iter.inner_name_index();
+    new_index = find_new_index(cur_index);
+    if (new_index != 0) {
+      RC_TRACE_WITH_THREAD(0x00080000, THREAD,
+        ("inner_name change: %d to %d", cur_index, new_index));
+      iter.set_inner_name_index(new_index);
+    }
+  } // end for each inner class
 
   // Attach each method in klass to the new constant pool and update
   // to use new constant pool indices as needed: