1 /*

     2  * Copyright 2005-2006 Sun Microsystems, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  *

    23  */

    24 # include "incls/_precompiled.incl"

    25 # include "incls/_jvmtiClassFileReconstituter.cpp.incl"

    26 

    27 // FIXME: add Deprecated, LVT, LVTT attributes

    28 // FIXME: fix Synthetic attribute

    29 // FIXME: per Serguei, add error return handling for constantPoolOopDesc::copy_cpool_bytes()

    30 

    31 

    32 // Write the field information portion of ClassFile structure

    33 // JVMSpec|     u2 fields_count;

    34 // JVMSpec|     field_info fields[fields_count];

    35 void JvmtiClassFileReconstituter::write_field_infos() {

    36   HandleMark hm(thread());

    37   typeArrayHandle fields(thread(), ikh()->fields());

    38   int fields_length = fields->length();

    39   int num_fields = fields_length / instanceKlass::next_offset;

    40   objArrayHandle fields_anno(thread(), ikh()->fields_annotations());

    41 

    42   write_u2(num_fields);

    43   for (int index = 0; index < fields_length; index += instanceKlass::next_offset) {

    44     AccessFlags access_flags;

    45     int flags = fields->ushort_at(index + instanceKlass::access_flags_offset);

    46     access_flags.set_flags(flags);

    47     int name_index = fields->ushort_at(index + instanceKlass::name_index_offset);

    48     int signature_index = fields->ushort_at(index + instanceKlass::signature_index_offset);

    49     int initial_value_index = fields->ushort_at(index + instanceKlass::initval_index_offset);

    50     guarantee(name_index != 0 && signature_index != 0, "bad constant pool index for field");

    51     int offset = ikh()->offset_from_fields( index );

    52     int generic_signature_index =

    53                         fields->ushort_at(index + instanceKlass::generic_signature_offset);

    54     typeArrayHandle anno(thread(), fields_anno.not_null() ?

    55                                  (typeArrayOop)(fields_anno->obj_at(index / instanceKlass::next_offset)) :

    56                                  (typeArrayOop)NULL);

    57 

    58     // JVMSpec|   field_info {

    59     // JVMSpec|         u2 access_flags;

    60     // JVMSpec|         u2 name_index;

    61     // JVMSpec|         u2 descriptor_index;

    62     // JVMSpec|         u2 attributes_count;

    63     // JVMSpec|         attribute_info attributes[attributes_count];

    64     // JVMSpec|   }

    65 

    66     write_u2(flags & JVM_RECOGNIZED_FIELD_MODIFIERS);

    67     write_u2(name_index);

    68     write_u2(signature_index);

    69     int attr_count = 0;

    70     if (initial_value_index != 0) {

    71       ++attr_count;

    72     }

    73     if (access_flags.is_synthetic()) {

    74       // ++attr_count;

    75     }

    76     if (generic_signature_index != 0) {

    77       ++attr_count;

    78     }

    79     if (anno.not_null()) {

    80       ++attr_count;     // has RuntimeVisibleAnnotations attribute

    81     }

    82 

    83     write_u2(attr_count);

    84 

    85     if (initial_value_index != 0) {

    86       write_attribute_name_index("ConstantValue");

    87       write_u4(2); //length always 2

    88       write_u2(initial_value_index);

    89     }

    90     if (access_flags.is_synthetic()) {

    91       // write_synthetic_attribute();

    92     }

    93     if (generic_signature_index != 0) {

    94       write_signature_attribute(generic_signature_index);

    95     }

    96     if (anno.not_null()) {

    97       write_annotations_attribute("RuntimeVisibleAnnotations", anno);

    98     }

    99   }

   100 }

   101 

   102 // Write Code attribute

   103 // JVMSpec|   Code_attribute {

   104 // JVMSpec|     u2 attribute_name_index;

   105 // JVMSpec|     u4 attribute_length;

   106 // JVMSpec|     u2 max_stack;

   107 // JVMSpec|     u2 max_locals;

   108 // JVMSpec|     u4 code_length;

   109 // JVMSpec|     u1 code[code_length];

   110 // JVMSpec|     u2 exception_table_length;

   111 // JVMSpec|     {       u2 start_pc;

   112 // JVMSpec|             u2 end_pc;

   113 // JVMSpec|             u2  handler_pc;

   114 // JVMSpec|             u2  catch_type;

   115 // JVMSpec|     }       exception_table[exception_table_length];

   116 // JVMSpec|     u2 attributes_count;

   117 // JVMSpec|     attribute_info attributes[attributes_count];

   118 // JVMSpec|   }

   119 void JvmtiClassFileReconstituter::write_code_attribute(methodHandle method) {

   120   constMethodHandle const_method(thread(), method->constMethod());

   121   u2 line_num_cnt = 0;

   122   int stackmap_len = 0;

   123 

   124   // compute number and length of attributes -- FIXME: for now no LVT

   125   int attr_count = 0;

   126   int attr_size = 0;

   127   if (const_method->has_linenumber_table()) {

   128     line_num_cnt = line_number_table_entries(method);

   129     if (line_num_cnt != 0) {

   130       ++attr_count;

   131       // Compute the complete size of the line number table attribute:

   132       //      LineNumberTable_attribute {

   133       //        u2 attribute_name_index;

   134       //        u4 attribute_length;

   135       //        u2 line_number_table_length;

   136       //        {  u2 start_pc;

   137       //           u2 line_number;

   138       //        } line_number_table[line_number_table_length];

   139       //      }

   140       attr_size += 2 + 4 + 2 + line_num_cnt * (2 + 2);

   141     }

   142   }

   143   if (method->has_stackmap_table()) {

   144     stackmap_len = method->stackmap_data()->length();

   145     if (stackmap_len != 0) {

   146       ++attr_count;

   147       // Compute the  size of the stack map table attribute (VM stores raw):

   148       //      StackMapTable_attribute {

   149       //        u2 attribute_name_index;

   150       //        u4 attribute_length;

   151       //        u2 number_of_entries;

   152       //        stack_map_frame_entries[number_of_entries];

   153       //      }

   154       attr_size += 2 + 4 + stackmap_len;

   155     }

   156   }

   157 

   158   typeArrayHandle exception_table(thread(), const_method->exception_table());

   159   int exception_table_length = exception_table->length();

   160   int exception_table_entries = exception_table_length / 4;

   161   int code_size = const_method->code_size();

   162   int size =

   163     2+2+4 +                                // max_stack, max_locals, code_length

   164     code_size +                            // code

   165     2 +                                    // exception_table_length

   166     (2+2+2+2) * exception_table_entries +  // exception_table

   167     2 +                                    // attributes_count

   168     attr_size;                             // attributes

   169 

   170   write_attribute_name_index("Code");

   171   write_u4(size);

   172   write_u2(method->max_stack());

   173   write_u2(method->max_locals());

   174   write_u4(code_size);

   175   copy_bytecodes(method, (unsigned char*)writeable_address(code_size));

   176   write_u2(exception_table_entries);

   177   for (int index = 0; index < exception_table_length; ) {

   178     write_u2(exception_table->int_at(index++));

   179     write_u2(exception_table->int_at(index++));

   180     write_u2(exception_table->int_at(index++));

   181     write_u2(exception_table->int_at(index++));

   182   }

   183   write_u2(attr_count);

   184   if (line_num_cnt != 0) {

   185     write_line_number_table_attribute(method, line_num_cnt);

   186   }

   187   if (stackmap_len != 0) {

   188     write_stackmap_table_attribute(method, stackmap_len);

   189   }

   190 

   191   // FIXME: write LVT attribute

   192 }

   193 

   194 // Write Exceptions attribute

   195 // JVMSpec|   Exceptions_attribute {

   196 // JVMSpec|     u2 attribute_name_index;

   197 // JVMSpec|     u4 attribute_length;

   198 // JVMSpec|     u2 number_of_exceptions;

   199 // JVMSpec|     u2 exception_index_table[number_of_exceptions];

   200 // JVMSpec|   }

   201 void JvmtiClassFileReconstituter::write_exceptions_attribute(constMethodHandle const_method) {

   202   CheckedExceptionElement* checked_exceptions = const_method->checked_exceptions_start();

   203   int checked_exceptions_length = const_method->checked_exceptions_length();

   204   int size =

   205     2 +                                    // number_of_exceptions

   206     2 * checked_exceptions_length;         // exception_index_table

   207 

   208   write_attribute_name_index("Exceptions");

   209   write_u4(size);

   210   write_u2(checked_exceptions_length);

   211   for (int index = 0; index < checked_exceptions_length; index++) {

   212     write_u2(checked_exceptions[index].class_cp_index);

   213   }

   214 }

   215 

   216 // Write SourceFile attribute

   217 // JVMSpec|   SourceFile_attribute {

   218 // JVMSpec|     u2 attribute_name_index;

   219 // JVMSpec|     u4 attribute_length;

   220 // JVMSpec|     u2 sourcefile_index;

   221 // JVMSpec|   }

   222 void JvmtiClassFileReconstituter::write_source_file_attribute() {

   223   assert(ikh()->source_file_name() != NULL, "caller must check");

   224 

   225   write_attribute_name_index("SourceFile");

   226   write_u4(2);  // always length 2

   227   write_u2(symbol_to_cpool_index(ikh()->source_file_name()));

   228 }

   229 

   230 // Write SourceDebugExtension attribute

   231 // JSR45|   SourceDebugExtension_attribute {

   232 // JSR45|       u2 attribute_name_index;

   233 // JSR45|       u4 attribute_length;

   234 // JSR45|       u2 sourcefile_index;

   235 // JSR45|   }

   236 void JvmtiClassFileReconstituter::write_source_debug_extension_attribute() {

   237   assert(ikh()->source_debug_extension() != NULL, "caller must check");

   238 

   239   write_attribute_name_index("SourceDebugExtension");

   240   write_u4(2);  // always length 2

   241   write_u2(symbol_to_cpool_index(ikh()->source_debug_extension()));

   242 }

   243 

   244 // Write (generic) Signature attribute

   245 // JVMSpec|   Signature_attribute {

   246 // JVMSpec|     u2 attribute_name_index;

   247 // JVMSpec|     u4 attribute_length;

   248 // JVMSpec|     u2 signature_index;

   249 // JVMSpec|   }

   250 void JvmtiClassFileReconstituter::write_signature_attribute(u2 generic_signature_index) {

   251   write_attribute_name_index("Signature");

   252   write_u4(2);  // always length 2

   253   write_u2(generic_signature_index);

   254 }

   255 

   256 // Compute the number of entries in the InnerClasses attribute

   257 u2 JvmtiClassFileReconstituter::inner_classes_attribute_length() {

   258   typeArrayOop inner_class_list = ikh()->inner_classes();

   259   return (inner_class_list == NULL) ? 0 : inner_class_list->length();

   260 }

   261 

   262 // Write an annotation attribute.  The VM stores them in raw form, so all we need

   263 // to do is add the attrubute name and fill in the length.

   264 // JSR202|   *Annotations_attribute {

   265 // JSR202|     u2 attribute_name_index;

   266 // JSR202|     u4 attribute_length;

   267 // JSR202|     ...

   268 // JSR202|   }

   269 void JvmtiClassFileReconstituter::write_annotations_attribute(const char* attr_name,

   270                                                               typeArrayHandle annos) {

   271   u4 length = annos->length();

   272   write_attribute_name_index(attr_name);

   273   write_u4(length);

   274   memcpy(writeable_address(length), annos->byte_at_addr(0), length);

   275 }

   276 

   277 

   278 // Write InnerClasses attribute

   279 // JVMSpec|   InnerClasses_attribute {

   280 // JVMSpec|     u2 attribute_name_index;

   281 // JVMSpec|     u4 attribute_length;

   282 // JVMSpec|     u2 number_of_classes;

   283 // JVMSpec|     {  u2 inner_class_info_index;

   284 // JVMSpec|        u2 outer_class_info_index;

   285 // JVMSpec|        u2 inner_name_index;

   286 // JVMSpec|        u2 inner_class_access_flags;

   287 // JVMSpec|     } classes[number_of_classes];

   288 // JVMSpec|   }

   289 void JvmtiClassFileReconstituter::write_inner_classes_attribute(int length) {

   290   typeArrayOop inner_class_list = ikh()->inner_classes();

   291   guarantee(inner_class_list != NULL && inner_class_list->length() == length,

   292             "caller must check");

   293   typeArrayHandle inner_class_list_h(thread(), inner_class_list);

   294   assert (length % instanceKlass::inner_class_next_offset == 0, "just checking");

   295   u2 entry_count = length / instanceKlass::inner_class_next_offset;

   296   u4 size = 2 + entry_count * (2+2+2+2);

   297 

   298   write_attribute_name_index("InnerClasses");

   299   write_u4(size);

   300   write_u2(entry_count);

   301   for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) {

   302     write_u2(inner_class_list_h->ushort_at(

   303                       i + instanceKlass::inner_class_inner_class_info_offset));

   304     write_u2(inner_class_list_h->ushort_at(

   305                       i + instanceKlass::inner_class_outer_class_info_offset));

   306     write_u2(inner_class_list_h->ushort_at(

   307                       i + instanceKlass::inner_class_inner_name_offset));

   308     write_u2(inner_class_list_h->ushort_at(

   309                       i + instanceKlass::inner_class_access_flags_offset));

   310   }

   311 }

   312 

   313 // Write Synthetic attribute

   314 // JVMSpec|   Synthetic_attribute {

   315 // JVMSpec|     u2 attribute_name_index;

   316 // JVMSpec|     u4 attribute_length;

   317 // JVMSpec|   }

   318 void JvmtiClassFileReconstituter::write_synthetic_attribute() {

   319   write_attribute_name_index("Synthetic");

   320   write_u4(0); //length always zero

   321 }

   322 

   323 // Compute size of LineNumberTable

   324 u2 JvmtiClassFileReconstituter::line_number_table_entries(methodHandle method) {

   325   // The line number table is compressed so we don't know how big it is until decompressed.

   326   // Decompression is really fast so we just do it twice.

   327   u2 num_entries = 0;

   328   CompressedLineNumberReadStream stream(method->compressed_linenumber_table());

   329   while (stream.read_pair()) {

   330     num_entries++;

   331   }

   332   return num_entries;

   333 }

   334 

   335 // Write LineNumberTable attribute

   336 // JVMSpec|   LineNumberTable_attribute {

   337 // JVMSpec|     u2 attribute_name_index;

   338 // JVMSpec|     u4 attribute_length;

   339 // JVMSpec|     u2 line_number_table_length;

   340 // JVMSpec|     {  u2 start_pc;

   341 // JVMSpec|        u2 line_number;

   342 // JVMSpec|     } line_number_table[line_number_table_length];

   343 // JVMSpec|   }

   344 void JvmtiClassFileReconstituter::write_line_number_table_attribute(methodHandle method,

   345                                                                     u2 num_entries) {

   346 

   347   write_attribute_name_index("LineNumberTable");

   348   write_u4(2 + num_entries * (2 + 2));

   349   write_u2(num_entries);

   350 

   351   CompressedLineNumberReadStream stream(method->compressed_linenumber_table());

   352   while (stream.read_pair()) {

   353     write_u2(stream.bci());

   354     write_u2(stream.line());

   355   }

   356 }

   357 

   358 // Write stack map table attribute

   359 // JSR-202|   StackMapTable_attribute {

   360 // JSR-202|     u2 attribute_name_index;

   361 // JSR-202|     u4 attribute_length;

   362 // JSR-202|     u2 number_of_entries;

   363 // JSR-202|     stack_map_frame_entries[number_of_entries];

   364 // JSR-202|   }

   365 void JvmtiClassFileReconstituter::write_stackmap_table_attribute(methodHandle method,

   366                                                                  int stackmap_len) {

   367 

   368   write_attribute_name_index("StackMapTable");

   369   write_u4(stackmap_len);

   370   memcpy(

   371     writeable_address(stackmap_len),

   372     (void*)(method->stackmap_data()->byte_at_addr(0)),

   373     stackmap_len);

   374 }

   375 

   376 // Write one method_info structure

   377 // JVMSpec|   method_info {

   378 // JVMSpec|     u2 access_flags;

   379 // JVMSpec|     u2 name_index;

   380 // JVMSpec|     u2 descriptor_index;

   381 // JVMSpec|     u2 attributes_count;

   382 // JVMSpec|     attribute_info attributes[attributes_count];

   383 // JVMSpec|   }

   384 void JvmtiClassFileReconstituter::write_method_info(methodHandle method) {

   385   AccessFlags access_flags = method->access_flags();

   386   constMethodHandle const_method(thread(), method->constMethod());

   387   u2 generic_signature_index = const_method->generic_signature_index();

   388   typeArrayHandle anno(thread(), method->annotations());

   389   typeArrayHandle param_anno(thread(), method->parameter_annotations());

   390   typeArrayHandle default_anno(thread(), method->annotation_default());

   391 

   392   write_u2(access_flags.get_flags() & JVM_RECOGNIZED_METHOD_MODIFIERS);

   393   write_u2(const_method->name_index());

   394   write_u2(const_method->signature_index());

   395 

   396   // write attributes in the same order javac does, so we can test with byte for

   397   // byte comparison

   398   int attr_count = 0;

   399   if (const_method->code_size() != 0) {

   400     ++attr_count;     // has Code attribute

   401   }

   402   if (const_method->has_checked_exceptions()) {

   403     ++attr_count;     // has Exceptions attribute

   404   }

   405   if (default_anno.not_null()) {

   406     ++attr_count;     // has AnnotationDefault attribute

   407   }

   408   // Deprecated attribute would go here

   409   if (access_flags.is_synthetic()) { // FIXME

   410     // ++attr_count;

   411   }

   412   if (generic_signature_index != 0) {

   413     ++attr_count;

   414   }

   415   if (anno.not_null()) {

   416     ++attr_count;     // has RuntimeVisibleAnnotations attribute

   417   }

   418   if (param_anno.not_null()) {

   419     ++attr_count;     // has RuntimeVisibleParameterAnnotations attribute

   420   }

   421 

   422   write_u2(attr_count);

   423   if (const_method->code_size() > 0) {

   424     write_code_attribute(method);

   425   }

   426   if (const_method->has_checked_exceptions()) {

   427     write_exceptions_attribute(const_method);

   428   }

   429   if (default_anno.not_null()) {

   430     write_annotations_attribute("AnnotationDefault", default_anno);

   431   }

   432   // Deprecated attribute would go here

   433   if (access_flags.is_synthetic()) {

   434     // write_synthetic_attribute();

   435   }

   436   if (generic_signature_index != 0) {

   437     write_signature_attribute(generic_signature_index);

   438   }

   439   if (anno.not_null()) {

   440     write_annotations_attribute("RuntimeVisibleAnnotations", anno);

   441   }

   442   if (param_anno.not_null()) {

   443     write_annotations_attribute("RuntimeVisibleParameterAnnotations", param_anno);

   444   }

   445 }

   446 

   447 // Write the class attributes portion of ClassFile structure

   448 // JVMSpec|     u2 attributes_count;

   449 // JVMSpec|     attribute_info attributes[attributes_count];

   450 void JvmtiClassFileReconstituter::write_class_attributes() {

   451   u2 inner_classes_length = inner_classes_attribute_length();

   452   symbolHandle generic_signature(thread(), ikh()->generic_signature());

   453   typeArrayHandle anno(thread(), ikh()->class_annotations());

   454 

   455   int attr_count = 0;

   456   if (generic_signature() != NULL) {

   457     ++attr_count;

   458   }

   459   if (ikh()->source_file_name() != NULL) {

   460     ++attr_count;

   461   }

   462   if (ikh()->source_debug_extension() != NULL) {

   463     ++attr_count;

   464   }

   465   if (inner_classes_length > 0) {

   466     ++attr_count;

   467   }

   468   if (anno.not_null()) {

   469     ++attr_count;     // has RuntimeVisibleAnnotations attribute

   470   }

   471 

   472   write_u2(attr_count);

   473 

   474   if (generic_signature() != NULL) {

   475     write_signature_attribute(symbol_to_cpool_index(generic_signature()));

   476   }

   477   if (ikh()->source_file_name() != NULL) {

   478     write_source_file_attribute();

   479   }

   480   if (ikh()->source_debug_extension() != NULL) {

   481     write_source_debug_extension_attribute();

   482   }

   483   if (inner_classes_length > 0) {

   484     write_inner_classes_attribute(inner_classes_length);

   485   }

   486   if (anno.not_null()) {

   487     write_annotations_attribute("RuntimeVisibleAnnotations", anno);

   488   }

   489 }

   490 

   491 // Write the method information portion of ClassFile structure

   492 // JVMSpec|     u2 methods_count;

   493 // JVMSpec|     method_info methods[methods_count];

   494 void JvmtiClassFileReconstituter::write_method_infos() {

   495   HandleMark hm(thread());

   496   objArrayHandle methods(thread(), ikh()->methods());

   497   int num_methods = methods->length();

   498 

   499   write_u2(num_methods);

   500   if (JvmtiExport::can_maintain_original_method_order()) {

   501     int index;

   502     int original_index;

   503     int* method_order = NEW_RESOURCE_ARRAY(int, num_methods);

   504 

   505     // invert the method order mapping

   506     for (index = 0; index < num_methods; index++) {

   507       original_index = ikh()->method_ordering()->int_at(index);

   508       assert(original_index >= 0 && original_index < num_methods,

   509              "invalid original method index");

   510       method_order[original_index] = index;

   511     }

   512 

   513     // write in original order

   514     for (original_index = 0; original_index < num_methods; original_index++) {

   515       index = method_order[original_index];

   516       methodHandle method(thread(), (methodOop)(ikh()->methods()->obj_at(index)));

   517       write_method_info(method);

   518     }

   519   } else {

   520     // method order not preserved just dump the method infos

   521     for (int index = 0; index < num_methods; index++) {

   522       methodHandle method(thread(), (methodOop)(ikh()->methods()->obj_at(index)));

   523       write_method_info(method);

   524     }

   525   }

   526 }

   527 

   528 void JvmtiClassFileReconstituter::write_class_file_format() {

   529   ReallocMark();

   530 

   531   // JVMSpec|   ClassFile {

   532   // JVMSpec|           u4 magic;

   533   write_u4(0xCAFEBABE);

   534 

   535   // JVMSpec|           u2 minor_version;

   536   // JVMSpec|           u2 major_version;

   537   write_u2(ikh()->minor_version());

   538   u2 major = ikh()->major_version();

   539   write_u2(major);

   540 

   541   // JVMSpec|           u2 constant_pool_count;

   542   // JVMSpec|           cp_info constant_pool[constant_pool_count-1];

   543   write_u2(cpool()->length());

   544   copy_cpool_bytes(writeable_address(cpool_size()));

   545 

   546   // JVMSpec|           u2 access_flags;

   547   write_u2(ikh()->access_flags().get_flags() & JVM_RECOGNIZED_CLASS_MODIFIERS);

   548 

   549   // JVMSpec|           u2 this_class;

   550   // JVMSpec|           u2 super_class;

   551   write_u2(class_symbol_to_cpool_index(ikh()->name()));

   552   klassOop super_class = ikh()->super();

   553   write_u2(super_class == NULL? 0 :  // zero for java.lang.Object

   554                 class_symbol_to_cpool_index(super_class->klass_part()->name()));

   555 

   556   // JVMSpec|           u2 interfaces_count;

   557   // JVMSpec|           u2 interfaces[interfaces_count];

   558   objArrayHandle interfaces(thread(), ikh()->local_interfaces());

   559   int num_interfaces = interfaces->length();

   560   write_u2(num_interfaces);

   561   for (int index = 0; index < num_interfaces; index++) {

   562     HandleMark hm(thread());

   563     instanceKlassHandle iikh(thread(), klassOop(interfaces->obj_at(index)));

   564     write_u2(class_symbol_to_cpool_index(iikh->name()));

   565   }

   566 

   567   // JVMSpec|           u2 fields_count;

   568   // JVMSpec|           field_info fields[fields_count];

   569   write_field_infos();

   570 

   571   // JVMSpec|           u2 methods_count;

   572   // JVMSpec|           method_info methods[methods_count];

   573   write_method_infos();

   574 

   575   // JVMSpec|           u2 attributes_count;

   576   // JVMSpec|           attribute_info attributes[attributes_count];

   577   // JVMSpec|   } /* end ClassFile 8?

   578   write_class_attributes();

   579 }

   580 

   581 address JvmtiClassFileReconstituter::writeable_address(size_t size) {

   582   size_t used_size = _buffer_ptr - _buffer;

   583   if (size + used_size >= _buffer_size) {

   584     // compute the new buffer size: must be at least twice as big as before

   585     // plus whatever new is being used; then convert to nice clean block boundary

   586     size_t new_buffer_size = (size + _buffer_size*2 + 1) / initial_buffer_size

   587                                                          * initial_buffer_size;

   588 

   589     // VM goes belly-up if the memory isn't available, so cannot do OOM processing

   590     _buffer = REALLOC_RESOURCE_ARRAY(u1, _buffer, _buffer_size, new_buffer_size);

   591     _buffer_size = new_buffer_size;

   592     _buffer_ptr = _buffer + used_size;

   593   }

   594   u1* ret_ptr = _buffer_ptr;

   595   _buffer_ptr += size;

   596   return ret_ptr;

   597 }

   598 

   599 void JvmtiClassFileReconstituter::write_attribute_name_index(const char* name) {

   600   unsigned int hash_ignored;

   601   symbolOop sym = SymbolTable::lookup_only(name, (int)strlen(name), hash_ignored);

   602   assert(sym != NULL, "attribute name symbol not found");

   603   u2 attr_name_index = symbol_to_cpool_index(sym);

   604   assert(attr_name_index != 0, "attribute name symbol not in constant pool");

   605   write_u2(attr_name_index);

   606 }

   607 

   608 void JvmtiClassFileReconstituter::write_u1(u1 x) {

   609   *writeable_address(1) = x;

   610 }

   611 

   612 void JvmtiClassFileReconstituter::write_u2(u2 x) {

   613   Bytes::put_Java_u2(writeable_address(2), x);

   614 }

   615 

   616 void JvmtiClassFileReconstituter::write_u4(u4 x) {

   617   Bytes::put_Java_u4(writeable_address(4), x);

   618 }

   619 

   620 void JvmtiClassFileReconstituter::write_u8(u8 x) {

   621   Bytes::put_Java_u8(writeable_address(8), x);

   622 }

   623 

   624 void JvmtiClassFileReconstituter::copy_bytecodes(methodHandle mh,

   625                                                  unsigned char* bytecodes) {

   626   // use a BytecodeStream to iterate over the bytecodes. JVM/fast bytecodes

   627   // and the breakpoint bytecode are converted to their original bytecodes.

   628 

   629   BytecodeStream bs(mh);

   630 

   631   unsigned char* p = bytecodes;

   632   Bytecodes::Code code;

   633   bool is_rewritten = instanceKlass::cast(mh->method_holder())->is_rewritten();

   634 

   635   while ((code = bs.next()) >= 0) {

   636     assert(Bytecodes::is_java_code(code), "sanity check");

   637     assert(code != Bytecodes::_breakpoint, "sanity check");

   638 

   639     // length of bytecode (mnemonic + operands)

   640     address bcp = bs.bcp();

   641     int len = bs.next_bcp() - bcp;

   642     assert(len > 0, "length must be > 0");

   643 

   644     // copy the bytecodes

   645     *p = (unsigned char) (bs.is_wide()? Bytecodes::_wide : code);

   646     if (len > 1) {

   647       memcpy(p+1, bcp+1, len-1);

   648     }

   649 

   650     // During linking the get/put and invoke instructions are rewritten

   651     // with an index into the constant pool cache. The original constant

   652     // pool index must be returned to caller.  Rewrite the index.

   653     if (is_rewritten && len >= 3) {

   654       switch (code) {

   655       case Bytecodes::_getstatic       :  // fall through

   656       case Bytecodes::_putstatic       :  // fall through

   657       case Bytecodes::_getfield        :  // fall through

   658       case Bytecodes::_putfield        :  // fall through

   659       case Bytecodes::_invokevirtual   :  // fall through

   660       case Bytecodes::_invokespecial   :  // fall through

   661       case Bytecodes::_invokestatic    :  // fall through

   662       case Bytecodes::_invokeinterface :

   663         assert(len == 3 || (code == Bytecodes::_invokeinterface && len ==5),

   664                "sanity check");

   665         // cache cannot be pre-fetched since some classes won't have it yet

   666         ConstantPoolCacheEntry* entry =

   667           mh->constants()->cache()->entry_at(Bytes::get_native_u2(bcp+1));

   668         int i = entry->constant_pool_index();

   669         assert(i < mh->constants()->length(), "sanity check");

   670         Bytes::put_Java_u2((address)(p+1), (u2)i);     // java byte ordering

   671         break;

   672       }

   673     }

   674 

   675     p += len;

   676   }

   677 }