diff -r 195309a6c7d5 -r fab8496eb541 src/hotspot/share/classfile/javaClasses.inline.hpp
--- a/src/hotspot/share/classfile/javaClasses.inline.hpp	Wed Mar 13 15:22:28 2019 +0100
+++ b/src/hotspot/share/classfile/javaClasses.inline.hpp	Wed Mar 13 17:32:17 2019 +0100
@@ -39,31 +39,44 @@
   assert(initialized, "Must be initialized");
   string->obj_field_put_raw(value_offset, buffer);
 }
+
 void java_lang_String::set_value(oop string, typeArrayOop buffer) {
   assert(initialized && (value_offset > 0), "Must be initialized");
   string->obj_field_put(value_offset, (oop)buffer);
 }
+
 void java_lang_String::set_hash(oop string, unsigned int hash) {
   assert(initialized && (hash_offset > 0), "Must be initialized");
   string->int_field_put(hash_offset, hash);
 }
 
 // Accessors
+bool java_lang_String::value_equals(typeArrayOop str_value1, typeArrayOop str_value2) {
+  return (oopDesc::equals(str_value1, str_value2) ||
+          (str_value1->length() == str_value2->length() &&
+           (!memcmp(str_value1->base(T_BYTE),
+                    str_value2->base(T_BYTE),
+                    str_value2->length() * sizeof(jbyte)))));
+}
+
 typeArrayOop java_lang_String::value(oop java_string) {
   assert(initialized && (value_offset > 0), "Must be initialized");
   assert(is_instance(java_string), "must be java_string");
   return (typeArrayOop) java_string->obj_field(value_offset);
 }
+
 typeArrayOop java_lang_String::value_no_keepalive(oop java_string) {
   assert(initialized && (value_offset > 0), "Must be initialized");
   assert(is_instance(java_string), "must be java_string");
   return (typeArrayOop) java_string->obj_field_access<AS_NO_KEEPALIVE>(value_offset);
 }
+
 unsigned int java_lang_String::hash(oop java_string) {
   assert(initialized && (hash_offset > 0), "Must be initialized");
   assert(is_instance(java_string), "must be java_string");
   return java_string->int_field(hash_offset);
 }
+
 bool java_lang_String::is_latin1(oop java_string) {
   assert(initialized && (coder_offset > 0), "Must be initialized");
   assert(is_instance(java_string), "must be java_string");
@@ -71,11 +84,12 @@
   assert(CompactStrings || coder == CODER_UTF16, "Must be UTF16 without CompactStrings");
   return coder == CODER_LATIN1;
 }
+
 int java_lang_String::length(oop java_string, typeArrayOop value) {
   assert(initialized, "Must be initialized");
   assert(is_instance(java_string), "must be java_string");
-  assert(oopDesc::equals(value, java_lang_String::value(java_string)),
-         "value must be same as java_lang_String::value(java_string)");
+  assert(value_equals(value, java_lang_String::value(java_string)),
+         "value must be equal to java_lang_String::value(java_string)");
   if (value == NULL) {
     return 0;
   }
@@ -86,6 +100,7 @@
   }
   return arr_length;
 }
+
 int java_lang_String::length(oop java_string) {
   assert(initialized, "Must be initialized");
   assert(is_instance(java_string), "must be java_string");
@@ -101,42 +116,55 @@
 oop java_lang_ref_Reference::referent(oop ref) {
   return ref->obj_field(referent_offset);
 }
+
 void java_lang_ref_Reference::set_referent(oop ref, oop value) {
   ref->obj_field_put(referent_offset, value);
 }
+
 void java_lang_ref_Reference::set_referent_raw(oop ref, oop value) {
   ref->obj_field_put_raw(referent_offset, value);
 }
+
 HeapWord* java_lang_ref_Reference::referent_addr_raw(oop ref) {
   return ref->obj_field_addr_raw<HeapWord>(referent_offset);
 }
+
 oop java_lang_ref_Reference::next(oop ref) {
   return ref->obj_field(next_offset);
 }
+
 void java_lang_ref_Reference::set_next(oop ref, oop value) {
   ref->obj_field_put(next_offset, value);
 }
+
 void java_lang_ref_Reference::set_next_raw(oop ref, oop value) {
   ref->obj_field_put_raw(next_offset, value);
 }
+
 HeapWord* java_lang_ref_Reference::next_addr_raw(oop ref) {
   return ref->obj_field_addr_raw<HeapWord>(next_offset);
 }
+
 oop java_lang_ref_Reference::discovered(oop ref) {
   return ref->obj_field(discovered_offset);
 }
+
 void java_lang_ref_Reference::set_discovered(oop ref, oop value) {
   ref->obj_field_put(discovered_offset, value);
 }
+
 void java_lang_ref_Reference::set_discovered_raw(oop ref, oop value) {
   ref->obj_field_put_raw(discovered_offset, value);
 }
+
 HeapWord* java_lang_ref_Reference::discovered_addr_raw(oop ref) {
   return ref->obj_field_addr_raw<HeapWord>(discovered_offset);
 }
+
 bool java_lang_ref_Reference::is_final(oop ref) {
   return InstanceKlass::cast(ref->klass())->reference_type() == REF_FINAL;
 }
+
 bool java_lang_ref_Reference::is_phantom(oop ref) {
   return InstanceKlass::cast(ref->klass())->reference_type() == REF_PHANTOM;
 }