1 /*

     2  * Copyright (c) 2005, 2017, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  *

    23  */

    24 

    25 #include "precompiled.hpp"

    26 #include "classfile/symbolTable.hpp"

    27 #include "interpreter/bytecodeStream.hpp"

    28 #include "oops/fieldStreams.hpp"

    29 #include "prims/jvmtiClassFileReconstituter.hpp"

    30 #include "runtime/signature.hpp"

    31 #include "utilities/bytes.hpp"

    32 

    33 // FIXME: add Deprecated attribute

    34 // FIXME: fix Synthetic attribute

    35 // FIXME: per Serguei, add error return handling for ConstantPool::copy_cpool_bytes()

    36 

    37 

    38 // Write the field information portion of ClassFile structure

    39 // JVMSpec|     u2 fields_count;

    40 // JVMSpec|     field_info fields[fields_count];

    41 void JvmtiClassFileReconstituter::write_field_infos() {

    42   HandleMark hm(thread());

    43   Array<AnnotationArray*>* fields_anno = ik()->fields_annotations();

    44   Array<AnnotationArray*>* fields_type_anno = ik()->fields_type_annotations();

    45 

    46   // Compute the real number of Java fields

    47   int java_fields = ik()->java_fields_count();

    48 

    49   write_u2(java_fields);

    50   for (JavaFieldStream fs(ik()); !fs.done(); fs.next()) {

    51     AccessFlags access_flags = fs.access_flags();

    52     int name_index = fs.name_index();

    53     int signature_index = fs.signature_index();

    54     int initial_value_index = fs.initval_index();

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

    56     // int offset = ik()->field_offset( index );

    57     int generic_signature_index = fs.generic_signature_index();

    58     AnnotationArray* anno = fields_anno == NULL ? NULL : fields_anno->at(fs.index());

    59     AnnotationArray* type_anno = fields_type_anno == NULL ? NULL : fields_type_anno->at(fs.index());

    60 

    61     // JVMSpec|   field_info {

    62     // JVMSpec|         u2 access_flags;

    63     // JVMSpec|         u2 name_index;

    64     // JVMSpec|         u2 descriptor_index;

    65     // JVMSpec|         u2 attributes_count;

    66     // JVMSpec|         attribute_info attributes[attributes_count];

    67     // JVMSpec|   }

    68 

    69     write_u2(access_flags.as_int() & JVM_RECOGNIZED_FIELD_MODIFIERS);

    70     write_u2(name_index);

    71     write_u2(signature_index);

    72     int attr_count = 0;

    73     if (initial_value_index != 0) {

    74       ++attr_count;

    75     }

    76     if (access_flags.is_synthetic()) {

    77       // ++attr_count;

    78     }

    79     if (generic_signature_index != 0) {

    80       ++attr_count;

    81     }

    82     if (anno != NULL) {

    83       ++attr_count;     // has RuntimeVisibleAnnotations attribute

    84     }

    85     if (type_anno != NULL) {

    86       ++attr_count;     // has RuntimeVisibleTypeAnnotations attribute

    87     }

    88 

    89     write_u2(attr_count);

    90 

    91     if (initial_value_index != 0) {

    92       write_attribute_name_index("ConstantValue");

    93       write_u4(2); //length always 2

    94       write_u2(initial_value_index);

    95     }

    96     if (access_flags.is_synthetic()) {

    97       // write_synthetic_attribute();

    98     }

    99     if (generic_signature_index != 0) {

   100       write_signature_attribute(generic_signature_index);

   101     }

   102     if (anno != NULL) {

   103       write_annotations_attribute("RuntimeVisibleAnnotations", anno);

   104     }

   105     if (type_anno != NULL) {

   106       write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);

   107     }

   108   }

   109 }

   110 

   111 // Write Code attribute

   112 // JVMSpec|   Code_attribute {

   113 // JVMSpec|     u2 attribute_name_index;

   114 // JVMSpec|     u4 attribute_length;

   115 // JVMSpec|     u2 max_stack;

   116 // JVMSpec|     u2 max_locals;

   117 // JVMSpec|     u4 code_length;

   118 // JVMSpec|     u1 code[code_length];

   119 // JVMSpec|     u2 exception_table_length;

   120 // JVMSpec|     {       u2 start_pc;

   121 // JVMSpec|             u2 end_pc;

   122 // JVMSpec|             u2  handler_pc;

   123 // JVMSpec|             u2  catch_type;

   124 // JVMSpec|     }       exception_table[exception_table_length];

   125 // JVMSpec|     u2 attributes_count;

   126 // JVMSpec|     attribute_info attributes[attributes_count];

   127 // JVMSpec|   }

   128 void JvmtiClassFileReconstituter::write_code_attribute(const methodHandle& method) {

   129   ConstMethod* const_method = method->constMethod();

   130   u2 line_num_cnt = 0;

   131   int stackmap_len = 0;

   132   int local_variable_table_length = 0;

   133   int local_variable_type_table_length = 0;

   134 

   135   // compute number and length of attributes

   136   int attr_count = 0;

   137   int attr_size = 0;

   138   if (const_method->has_linenumber_table()) {

   139     line_num_cnt = line_number_table_entries(method);

   140     if (line_num_cnt != 0) {

   141       ++attr_count;

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

   143       //      LineNumberTable_attribute {

   144       //        u2 attribute_name_index;

   145       //        u4 attribute_length;

   146       //        u2 line_number_table_length;

   147       //        {  u2 start_pc;

   148       //           u2 line_number;

   149       //        } line_number_table[line_number_table_length];

   150       //      }

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

   152     }

   153   }

   154   if (method->has_stackmap_table()) {

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

   156     if (stackmap_len != 0) {

   157       ++attr_count;

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

   159       //      StackMapTable_attribute {

   160       //        u2 attribute_name_index;

   161       //        u4 attribute_length;

   162       //        u2 number_of_entries;

   163       //        stack_map_frame_entries[number_of_entries];

   164       //      }

   165       attr_size += 2 + 4 + stackmap_len;

   166     }

   167   }

   168   if (method->has_localvariable_table()) {

   169     local_variable_table_length = method->localvariable_table_length();

   170     if (local_variable_table_length != 0) {

   171       ++attr_count;

   172       // Compute the size of the local variable table attribute (VM stores raw):

   173       // LocalVariableTable_attribute {

   174       //   u2 attribute_name_index;

   175       //   u4 attribute_length;

   176       //   u2 local_variable_table_length;

   177       //   {

   178       //     u2 start_pc;

   179       //     u2 length;

   180       //     u2 name_index;

   181       //     u2 descriptor_index;

   182       //     u2 index;

   183       //   }

   184       attr_size += 2 + 4 + 2 + local_variable_table_length * (2 + 2 + 2 + 2 + 2);

   185 

   186       // Local variables with generic signatures must have LVTT entries

   187       LocalVariableTableElement *elem = method->localvariable_table_start();

   188       for (int idx = 0; idx < local_variable_table_length; idx++) {

   189         if (elem[idx].signature_cp_index != 0) {

   190           local_variable_type_table_length++;

   191         }

   192       }

   193 

   194       if (local_variable_type_table_length != 0) {

   195         ++attr_count;

   196         // Compute the size of the local variable type table attribute (VM stores raw):

   197         // LocalVariableTypeTable_attribute {

   198         //   u2 attribute_name_index;

   199         //   u4 attribute_length;

   200         //   u2 local_variable_type_table_length;

   201         //   {

   202         //     u2 start_pc;

   203         //     u2 length;

   204         //     u2 name_index;

   205         //     u2 signature_index;

   206         //     u2 index;

   207         //   }

   208         attr_size += 2 + 4 + 2 + local_variable_type_table_length * (2 + 2 + 2 + 2 + 2);

   209       }

   210     }

   211   }

   212 

   213   ExceptionTable exception_table(method());

   214   int exception_table_length = exception_table.length();

   215   int code_size = const_method->code_size();

   216   int size =

   217     2+2+4 +                                // max_stack, max_locals, code_length

   218     code_size +                            // code

   219     2 +                                    // exception_table_length

   220     (2+2+2+2) * exception_table_length +   // exception_table

   221     2 +                                    // attributes_count

   222     attr_size;                             // attributes

   223 

   224   write_attribute_name_index("Code");

   225   write_u4(size);

   226   write_u2(method->verifier_max_stack());

   227   write_u2(method->max_locals());

   228   write_u4(code_size);

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

   230   write_u2(exception_table_length);

   231   for (int index = 0; index < exception_table_length; index++) {

   232     write_u2(exception_table.start_pc(index));

   233     write_u2(exception_table.end_pc(index));

   234     write_u2(exception_table.handler_pc(index));

   235     write_u2(exception_table.catch_type_index(index));

   236   }

   237   write_u2(attr_count);

   238   if (line_num_cnt != 0) {

   239     write_line_number_table_attribute(method, line_num_cnt);

   240   }

   241   if (stackmap_len != 0) {

   242     write_stackmap_table_attribute(method, stackmap_len);

   243   }

   244   if (local_variable_table_length != 0) {

   245     write_local_variable_table_attribute(method, local_variable_table_length);

   246   }

   247   if (local_variable_type_table_length != 0) {

   248     write_local_variable_type_table_attribute(method, local_variable_type_table_length);

   249   }

   250 }

   251 

   252 // Write Exceptions attribute

   253 // JVMSpec|   Exceptions_attribute {

   254 // JVMSpec|     u2 attribute_name_index;

   255 // JVMSpec|     u4 attribute_length;

   256 // JVMSpec|     u2 number_of_exceptions;

   257 // JVMSpec|     u2 exception_index_table[number_of_exceptions];

   258 // JVMSpec|   }

   259 void JvmtiClassFileReconstituter::write_exceptions_attribute(ConstMethod* const_method) {

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

   261   int checked_exceptions_length = const_method->checked_exceptions_length();

   262   int size =

   263     2 +                                    // number_of_exceptions

   264     2 * checked_exceptions_length;         // exception_index_table

   265 

   266   write_attribute_name_index("Exceptions");

   267   write_u4(size);

   268   write_u2(checked_exceptions_length);

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

   270     write_u2(checked_exceptions[index].class_cp_index);

   271   }

   272 }

   273 

   274 // Write SourceFile attribute

   275 // JVMSpec|   SourceFile_attribute {

   276 // JVMSpec|     u2 attribute_name_index;

   277 // JVMSpec|     u4 attribute_length;

   278 // JVMSpec|     u2 sourcefile_index;

   279 // JVMSpec|   }

   280 void JvmtiClassFileReconstituter::write_source_file_attribute() {

   281   assert(ik()->source_file_name() != NULL, "caller must check");

   282 

   283   write_attribute_name_index("SourceFile");

   284   write_u4(2);  // always length 2

   285   write_u2(symbol_to_cpool_index(ik()->source_file_name()));

   286 }

   287 

   288 // Write SourceDebugExtension attribute

   289 // JSR45|   SourceDebugExtension_attribute {

   290 // JSR45|       u2 attribute_name_index;

   291 // JSR45|       u4 attribute_length;

   292 // JSR45|       u1 debug_extension[attribute_length];

   293 // JSR45|   }

   294 void JvmtiClassFileReconstituter::write_source_debug_extension_attribute() {

   295   assert(ik()->source_debug_extension() != NULL, "caller must check");

   296 

   297   write_attribute_name_index("SourceDebugExtension");

   298   int len = (int)strlen(ik()->source_debug_extension());

   299   write_u4(len);

   300   u1* ext = (u1*)ik()->source_debug_extension();

   301   for (int i=0; i<len; i++) {

   302     write_u1(ext[i]);

   303   }

   304 }

   305 

   306 // Write (generic) Signature attribute

   307 // JVMSpec|   Signature_attribute {

   308 // JVMSpec|     u2 attribute_name_index;

   309 // JVMSpec|     u4 attribute_length;

   310 // JVMSpec|     u2 signature_index;

   311 // JVMSpec|   }

   312 void JvmtiClassFileReconstituter::write_signature_attribute(u2 generic_signature_index) {

   313   write_attribute_name_index("Signature");

   314   write_u4(2);  // always length 2

   315   write_u2(generic_signature_index);

   316 }

   317 

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

   319 u2 JvmtiClassFileReconstituter::inner_classes_attribute_length() {

   320   InnerClassesIterator iter(ik());

   321   return iter.length();

   322 }

   323 

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

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

   326 // JSR202|   *Annotations_attribute {

   327 // JSR202|     u2 attribute_name_index;

   328 // JSR202|     u4 attribute_length;

   329 // JSR202|     ...

   330 // JSR202|   }

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

   332                                                               AnnotationArray* annos) {

   333   u4 length = annos->length();

   334   write_attribute_name_index(attr_name);

   335   write_u4(length);

   336   memcpy(writeable_address(length), annos->adr_at(0), length);

   337 }

   338 

   339 //  BootstrapMethods_attribute {

   340 //    u2 attribute_name_index;

   341 //    u4 attribute_length;

   342 //    u2 num_bootstrap_methods;

   343 //    {   u2 bootstrap_method_ref;

   344 //        u2 num_bootstrap_arguments;

   345 //        u2 bootstrap_arguments[num_bootstrap_arguments];

   346 //    } bootstrap_methods[num_bootstrap_methods];

   347 //  }

   348 void JvmtiClassFileReconstituter::write_bootstrapmethod_attribute() {

   349   Array<u2>* operands = cpool()->operands();

   350   write_attribute_name_index("BootstrapMethods");

   351   int num_bootstrap_methods = ConstantPool::operand_array_length(operands);

   352 

   353   // calculate length of attribute

   354   int length = sizeof(u2); // num_bootstrap_methods

   355   for (int n = 0; n < num_bootstrap_methods; n++) {

   356     u2 num_bootstrap_arguments = cpool()->operand_argument_count_at(n);

   357     length += sizeof(u2); // bootstrap_method_ref

   358     length += sizeof(u2); // num_bootstrap_arguments

   359     length += sizeof(u2) * num_bootstrap_arguments; // bootstrap_arguments[num_bootstrap_arguments]

   360   }

   361   write_u4(length);

   362 

   363   // write attribute

   364   write_u2(num_bootstrap_methods);

   365   for (int n = 0; n < num_bootstrap_methods; n++) {

   366     u2 bootstrap_method_ref = cpool()->operand_bootstrap_method_ref_index_at(n);

   367     u2 num_bootstrap_arguments = cpool()->operand_argument_count_at(n);

   368     write_u2(bootstrap_method_ref);

   369     write_u2(num_bootstrap_arguments);

   370     for (int arg = 0; arg < num_bootstrap_arguments; arg++) {

   371       u2 bootstrap_argument = cpool()->operand_argument_index_at(n, arg);

   372       write_u2(bootstrap_argument);

   373     }

   374   }

   375 }

   376 

   377 

   378 // Write InnerClasses attribute

   379 // JVMSpec|   InnerClasses_attribute {

   380 // JVMSpec|     u2 attribute_name_index;

   381 // JVMSpec|     u4 attribute_length;

   382 // JVMSpec|     u2 number_of_classes;

   383 // JVMSpec|     {  u2 inner_class_info_index;

   384 // JVMSpec|        u2 outer_class_info_index;

   385 // JVMSpec|        u2 inner_name_index;

   386 // JVMSpec|        u2 inner_class_access_flags;

   387 // JVMSpec|     } classes[number_of_classes];

   388 // JVMSpec|   }

   389 void JvmtiClassFileReconstituter::write_inner_classes_attribute(int length) {

   390   InnerClassesIterator iter(ik());

   391   guarantee(iter.length() != 0 && iter.length() == length,

   392             "caller must check");

   393   u2 entry_count = length / InstanceKlass::inner_class_next_offset;

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

   395 

   396   write_attribute_name_index("InnerClasses");

   397   write_u4(size);

   398   write_u2(entry_count);

   399   for (; !iter.done(); iter.next()) {

   400     write_u2(iter.inner_class_info_index());

   401     write_u2(iter.outer_class_info_index());

   402     write_u2(iter.inner_name_index());

   403     write_u2(iter.inner_access_flags());

   404   }

   405 }

   406 

   407 // Write Synthetic attribute

   408 // JVMSpec|   Synthetic_attribute {

   409 // JVMSpec|     u2 attribute_name_index;

   410 // JVMSpec|     u4 attribute_length;

   411 // JVMSpec|   }

   412 void JvmtiClassFileReconstituter::write_synthetic_attribute() {

   413   write_attribute_name_index("Synthetic");

   414   write_u4(0); //length always zero

   415 }

   416 

   417 // Compute size of LineNumberTable

   418 u2 JvmtiClassFileReconstituter::line_number_table_entries(const methodHandle& method) {

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

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

   421   u2 num_entries = 0;

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

   423   while (stream.read_pair()) {

   424     num_entries++;

   425   }

   426   return num_entries;

   427 }

   428 

   429 // Write LineNumberTable attribute

   430 // JVMSpec|   LineNumberTable_attribute {

   431 // JVMSpec|     u2 attribute_name_index;

   432 // JVMSpec|     u4 attribute_length;

   433 // JVMSpec|     u2 line_number_table_length;

   434 // JVMSpec|     {  u2 start_pc;

   435 // JVMSpec|        u2 line_number;

   436 // JVMSpec|     } line_number_table[line_number_table_length];

   437 // JVMSpec|   }

   438 void JvmtiClassFileReconstituter::write_line_number_table_attribute(const methodHandle& method,

   439                                                                     u2 num_entries) {

   440 

   441   write_attribute_name_index("LineNumberTable");

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

   443   write_u2(num_entries);

   444 

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

   446   while (stream.read_pair()) {

   447     write_u2(stream.bci());

   448     write_u2(stream.line());

   449   }

   450 }

   451 

   452 // Write LocalVariableTable attribute

   453 // JVMSpec|   LocalVariableTable_attribute {

   454 // JVMSpec|     u2 attribute_name_index;

   455 // JVMSpec|     u4 attribute_length;

   456 // JVMSpec|     u2 local_variable_table_length;

   457 // JVMSpec|     {  u2 start_pc;

   458 // JVMSpec|       u2 length;

   459 // JVMSpec|       u2 name_index;

   460 // JVMSpec|       u2 descriptor_index;

   461 // JVMSpec|       u2 index;

   462 // JVMSpec|     } local_variable_table[local_variable_table_length];

   463 // JVMSpec|   }

   464 void JvmtiClassFileReconstituter::write_local_variable_table_attribute(const methodHandle& method, u2 num_entries) {

   465     write_attribute_name_index("LocalVariableTable");

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

   467     write_u2(num_entries);

   468 

   469     assert(method->localvariable_table_length() == num_entries, "just checking");

   470 

   471     LocalVariableTableElement *elem = method->localvariable_table_start();

   472     for (int j=0; j<method->localvariable_table_length(); j++) {

   473       write_u2(elem->start_bci);

   474       write_u2(elem->length);

   475       write_u2(elem->name_cp_index);

   476       write_u2(elem->descriptor_cp_index);

   477       write_u2(elem->slot);

   478       elem++;

   479     }

   480 }

   481 

   482 // Write LocalVariableTypeTable attribute

   483 // JVMSpec|   LocalVariableTypeTable_attribute {

   484 // JVMSpec|     u2 attribute_name_index;

   485 // JVMSpec|     u4 attribute_length;

   486 // JVMSpec|     u2 local_variable_type_table_length;

   487 // JVMSpec|     { u2 start_pc;

   488 // JVMSpec|       u2 length;

   489 // JVMSpec|       u2 name_index;

   490 // JVMSpec|       u2 signature_index;

   491 // JVMSpec|       u2 index;

   492 // JVMSpec|     } local_variable_type_table[local_variable_type_table_length];

   493 // JVMSpec|   }

   494 void JvmtiClassFileReconstituter::write_local_variable_type_table_attribute(const methodHandle& method, u2 num_entries) {

   495     write_attribute_name_index("LocalVariableTypeTable");

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

   497     write_u2(num_entries);

   498 

   499     LocalVariableTableElement *elem = method->localvariable_table_start();

   500     for (int j=0; j<method->localvariable_table_length(); j++) {

   501       if (elem->signature_cp_index > 0) {

   502         // Local variable has a generic signature - write LVTT attribute entry

   503         write_u2(elem->start_bci);

   504         write_u2(elem->length);

   505         write_u2(elem->name_cp_index);

   506         write_u2(elem->signature_cp_index);

   507         write_u2(elem->slot);

   508         num_entries--;

   509       }

   510       elem++;

   511     }

   512     assert(num_entries == 0, "just checking");

   513 }

   514 

   515 // Write stack map table attribute

   516 // JSR-202|   StackMapTable_attribute {

   517 // JSR-202|     u2 attribute_name_index;

   518 // JSR-202|     u4 attribute_length;

   519 // JSR-202|     u2 number_of_entries;

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

   521 // JSR-202|   }

   522 void JvmtiClassFileReconstituter::write_stackmap_table_attribute(const methodHandle& method,

   523                                                                  int stackmap_len) {

   524 

   525   write_attribute_name_index("StackMapTable");

   526   write_u4(stackmap_len);

   527   memcpy(

   528     writeable_address(stackmap_len),

   529     (void*)(method->stackmap_data()->adr_at(0)),

   530     stackmap_len);

   531 }

   532 

   533 // Write one method_info structure

   534 // JVMSpec|   method_info {

   535 // JVMSpec|     u2 access_flags;

   536 // JVMSpec|     u2 name_index;

   537 // JVMSpec|     u2 descriptor_index;

   538 // JVMSpec|     u2 attributes_count;

   539 // JVMSpec|     attribute_info attributes[attributes_count];

   540 // JVMSpec|   }

   541 void JvmtiClassFileReconstituter::write_method_info(const methodHandle& method) {

   542   AccessFlags access_flags = method->access_flags();

   543   ConstMethod* const_method = method->constMethod();

   544   u2 generic_signature_index = const_method->generic_signature_index();

   545   AnnotationArray* anno = method->annotations();

   546   AnnotationArray* param_anno = method->parameter_annotations();

   547   AnnotationArray* default_anno = method->annotation_default();

   548   AnnotationArray* type_anno = method->type_annotations();

   549 

   550   // skip generated default interface methods

   551   if (method->is_overpass()) {

   552     return;

   553   }

   554 

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

   556   write_u2(const_method->name_index());

   557   write_u2(const_method->signature_index());

   558 

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

   560   // byte comparison

   561   int attr_count = 0;

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

   563     ++attr_count;     // has Code attribute

   564   }

   565   if (const_method->has_checked_exceptions()) {

   566     ++attr_count;     // has Exceptions attribute

   567   }

   568   if (default_anno != NULL) {

   569     ++attr_count;     // has AnnotationDefault attribute

   570   }

   571   // Deprecated attribute would go here

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

   573     // ++attr_count;

   574   }

   575   if (generic_signature_index != 0) {

   576     ++attr_count;

   577   }

   578   if (anno != NULL) {

   579     ++attr_count;     // has RuntimeVisibleAnnotations attribute

   580   }

   581   if (param_anno != NULL) {

   582     ++attr_count;     // has RuntimeVisibleParameterAnnotations attribute

   583   }

   584   if (type_anno != NULL) {

   585     ++attr_count;     // has RuntimeVisibleTypeAnnotations attribute

   586   }

   587 

   588   write_u2(attr_count);

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

   590     write_code_attribute(method);

   591   }

   592   if (const_method->has_checked_exceptions()) {

   593     write_exceptions_attribute(const_method);

   594   }

   595   if (default_anno != NULL) {

   596     write_annotations_attribute("AnnotationDefault", default_anno);

   597   }

   598   // Deprecated attribute would go here

   599   if (access_flags.is_synthetic()) {

   600     // write_synthetic_attribute();

   601   }

   602   if (generic_signature_index != 0) {

   603     write_signature_attribute(generic_signature_index);

   604   }

   605   if (anno != NULL) {

   606     write_annotations_attribute("RuntimeVisibleAnnotations", anno);

   607   }

   608   if (param_anno != NULL) {

   609     write_annotations_attribute("RuntimeVisibleParameterAnnotations", param_anno);

   610   }

   611   if (type_anno != NULL) {

   612     write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);

   613   }

   614 }

   615 

   616 // Write the class attributes portion of ClassFile structure

   617 // JVMSpec|     u2 attributes_count;

   618 // JVMSpec|     attribute_info attributes[attributes_count];

   619 void JvmtiClassFileReconstituter::write_class_attributes() {

   620   u2 inner_classes_length = inner_classes_attribute_length();

   621   Symbol* generic_signature = ik()->generic_signature();

   622   AnnotationArray* anno = ik()->class_annotations();

   623   AnnotationArray* type_anno = ik()->class_type_annotations();

   624 

   625   int attr_count = 0;

   626   if (generic_signature != NULL) {

   627     ++attr_count;

   628   }

   629   if (ik()->source_file_name() != NULL) {

   630     ++attr_count;

   631   }

   632   if (ik()->source_debug_extension() != NULL) {

   633     ++attr_count;

   634   }

   635   if (inner_classes_length > 0) {

   636     ++attr_count;

   637   }

   638   if (anno != NULL) {

   639     ++attr_count;     // has RuntimeVisibleAnnotations attribute

   640   }

   641   if (type_anno != NULL) {

   642     ++attr_count;     // has RuntimeVisibleTypeAnnotations attribute

   643   }

   644   if (cpool()->operands() != NULL) {

   645     ++attr_count;

   646   }

   647 

   648   write_u2(attr_count);

   649 

   650   if (generic_signature != NULL) {

   651     write_signature_attribute(symbol_to_cpool_index(generic_signature));

   652   }

   653   if (ik()->source_file_name() != NULL) {

   654     write_source_file_attribute();

   655   }

   656   if (ik()->source_debug_extension() != NULL) {

   657     write_source_debug_extension_attribute();

   658   }

   659   if (inner_classes_length > 0) {

   660     write_inner_classes_attribute(inner_classes_length);

   661   }

   662   if (anno != NULL) {

   663     write_annotations_attribute("RuntimeVisibleAnnotations", anno);

   664   }

   665   if (type_anno != NULL) {

   666     write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);

   667   }

   668   if (cpool()->operands() != NULL) {

   669     write_bootstrapmethod_attribute();

   670   }

   671 }

   672 

   673 // Write the method information portion of ClassFile structure

   674 // JVMSpec|     u2 methods_count;

   675 // JVMSpec|     method_info methods[methods_count];

   676 void JvmtiClassFileReconstituter::write_method_infos() {

   677   HandleMark hm(thread());

   678   Array<Method*>* methods = ik()->methods();

   679   int num_methods = methods->length();

   680   int num_overpass = 0;

   681 

   682   // count the generated default interface methods

   683   // these will not be re-created by write_method_info

   684   // and should not be included in the total count

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

   686     Method* method = methods->at(index);

   687     if (method->is_overpass()) {

   688       num_overpass++;

   689     }

   690   }

   691 

   692   write_u2(num_methods - num_overpass);

   693   if (JvmtiExport::can_maintain_original_method_order()) {

   694     int index;

   695     int original_index;

   696     intArray method_order(num_methods, num_methods, 0);

   697 

   698     // invert the method order mapping

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

   700       original_index = ik()->method_ordering()->at(index);

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

   702              "invalid original method index");

   703       method_order.at_put(original_index, index);

   704     }

   705 

   706     // write in original order

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

   708       index = method_order.at(original_index);

   709       methodHandle method(thread(), methods->at(index));

   710       write_method_info(method);

   711     }

   712   } else {

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

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

   715       methodHandle method(thread(), methods->at(index));

   716       write_method_info(method);

   717     }

   718   }

   719 }

   720 

   721 void JvmtiClassFileReconstituter::write_class_file_format() {

   722   ReallocMark();

   723 

   724   // JVMSpec|   ClassFile {

   725   // JVMSpec|           u4 magic;

   726   write_u4(0xCAFEBABE);

   727 

   728   // JVMSpec|           u2 minor_version;

   729   // JVMSpec|           u2 major_version;

   730   write_u2(ik()->minor_version());

   731   u2 major = ik()->major_version();

   732   write_u2(major);

   733 

   734   // JVMSpec|           u2 constant_pool_count;

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

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

   737   copy_cpool_bytes(writeable_address(cpool_size()));

   738 

   739   // JVMSpec|           u2 access_flags;

   740   write_u2(ik()->access_flags().get_flags() & JVM_RECOGNIZED_CLASS_MODIFIERS);

   741 

   742   // JVMSpec|           u2 this_class;

   743   // JVMSpec|           u2 super_class;

   744   write_u2(class_symbol_to_cpool_index(ik()->name()));

   745   Klass* super_class = ik()->super();

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

   747                 class_symbol_to_cpool_index(super_class->name()));

   748 

   749   // JVMSpec|           u2 interfaces_count;

   750   // JVMSpec|           u2 interfaces[interfaces_count];

   751   Array<Klass*>* interfaces =  ik()->local_interfaces();

   752   int num_interfaces = interfaces->length();

   753   write_u2(num_interfaces);

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

   755     HandleMark hm(thread());

   756     InstanceKlass* iik = InstanceKlass::cast(interfaces->at(index));

   757     write_u2(class_symbol_to_cpool_index(iik->name()));

   758   }

   759 

   760   // JVMSpec|           u2 fields_count;

   761   // JVMSpec|           field_info fields[fields_count];

   762   write_field_infos();

   763 

   764   // JVMSpec|           u2 methods_count;

   765   // JVMSpec|           method_info methods[methods_count];

   766   write_method_infos();

   767 

   768   // JVMSpec|           u2 attributes_count;

   769   // JVMSpec|           attribute_info attributes[attributes_count];

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

   771   write_class_attributes();

   772 }

   773 

   774 address JvmtiClassFileReconstituter::writeable_address(size_t size) {

   775   size_t used_size = _buffer_ptr - _buffer;

   776   if (size + used_size >= _buffer_size) {

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

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

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

   780                                                          * initial_buffer_size;

   781 

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

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

   784     _buffer_size = new_buffer_size;

   785     _buffer_ptr = _buffer + used_size;

   786   }

   787   u1* ret_ptr = _buffer_ptr;

   788   _buffer_ptr += size;

   789   return ret_ptr;

   790 }

   791 

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

   793   TempNewSymbol sym = SymbolTable::probe(name, (int)strlen(name));

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

   795   u2 attr_name_index = symbol_to_cpool_index(sym);

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

   797   write_u2(attr_name_index);

   798 }

   799 

   800 void JvmtiClassFileReconstituter::write_u1(u1 x) {

   801   *writeable_address(1) = x;

   802 }

   803 

   804 void JvmtiClassFileReconstituter::write_u2(u2 x) {

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

   806 }

   807 

   808 void JvmtiClassFileReconstituter::write_u4(u4 x) {

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

   810 }

   811 

   812 void JvmtiClassFileReconstituter::write_u8(u8 x) {

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

   814 }

   815 

   816 void JvmtiClassFileReconstituter::copy_bytecodes(const methodHandle& mh,

   817                                                  unsigned char* bytecodes) {

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

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

   820 

   821   BytecodeStream bs(mh);

   822 

   823   unsigned char* p = bytecodes;

   824   Bytecodes::Code code;

   825   bool is_rewritten = mh->method_holder()->is_rewritten();

   826 

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

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

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

   830 

   831     // length of bytecode (mnemonic + operands)

   832     address bcp = bs.bcp();

   833     int     len = bs.instruction_size();

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

   835 

   836     // copy the bytecodes

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

   838     if (len > 1) {

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

   840     }

   841 

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

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

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

   845     if (is_rewritten && len > 1) {

   846       bool is_wide = false;

   847       switch (code) {

   848       case Bytecodes::_getstatic       :  // fall through

   849       case Bytecodes::_putstatic       :  // fall through

   850       case Bytecodes::_getfield        :  // fall through

   851       case Bytecodes::_putfield        :  // fall through

   852       case Bytecodes::_invokevirtual   :  // fall through

   853       case Bytecodes::_invokespecial   :  // fall through

   854       case Bytecodes::_invokestatic    :  // fall through

   855       case Bytecodes::_invokedynamic   :  // fall through

   856       case Bytecodes::_invokeinterface : {

   857         assert(len == 3 ||

   858                (code == Bytecodes::_invokeinterface && len == 5) ||

   859                (code == Bytecodes::_invokedynamic   && len == 5),

   860                "sanity check");

   861 

   862         int cpci = Bytes::get_native_u2(bcp+1);

   863         bool is_invokedynamic = (code == Bytecodes::_invokedynamic);

   864         ConstantPoolCacheEntry* entry;

   865         if (is_invokedynamic) {

   866           cpci = Bytes::get_native_u4(bcp+1);

   867           entry = mh->constants()->invokedynamic_cp_cache_entry_at(cpci);

   868         } else {

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

   870           entry = mh->constants()->cache()->entry_at(cpci);

   871         }

   872         int i = entry->constant_pool_index();

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

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

   875         if (is_invokedynamic)  *(p+3) = *(p+4) = 0;

   876         break;

   877       }

   878       case Bytecodes::_ldc_w:

   879         is_wide = true; // fall through

   880       case Bytecodes::_ldc: {

   881         if (bs.raw_code() == Bytecodes::_fast_aldc || bs.raw_code() == Bytecodes::_fast_aldc_w) {

   882           int cpci = is_wide ? Bytes::get_native_u2(bcp+1) : (u1)(*(bcp+1));

   883           int i = mh->constants()->object_to_cp_index(cpci);

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

   885           if (is_wide) {

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

   887           } else {

   888             *(p+1) = (u1)i;

   889           }

   890         }

   891         break;

   892         }

   893       default:

   894         break;

   895       }

   896     }

   897 

   898     p += len;

   899   }

   900 }