Java example source code file (jvmtiClassFileReconstituter.cpp)
The jvmtiClassFileReconstituter.cpp Java example source code/*
* Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "classfile/symbolTable.hpp"
#include "interpreter/bytecodeStream.hpp"
#include "oops/fieldStreams.hpp"
#include "prims/jvmtiClassFileReconstituter.hpp"
#include "runtime/signature.hpp"
#ifdef TARGET_ARCH_x86
# include "bytes_x86.hpp"
#endif
#ifdef TARGET_ARCH_sparc
# include "bytes_sparc.hpp"
#endif
#ifdef TARGET_ARCH_zero
# include "bytes_zero.hpp"
#endif
#ifdef TARGET_ARCH_arm
# include "bytes_arm.hpp"
#endif
#ifdef TARGET_ARCH_ppc
# include "bytes_ppc.hpp"
#endif
// FIXME: add Deprecated attribute
// FIXME: fix Synthetic attribute
// FIXME: per Serguei, add error return handling for ConstantPool::copy_cpool_bytes()
// Write the field information portion of ClassFile structure
// JVMSpec| u2 fields_count;
// JVMSpec| field_info fields[fields_count];
void JvmtiClassFileReconstituter::write_field_infos() {
HandleMark hm(thread());
Array<AnnotationArray*>* fields_anno = ikh()->fields_annotations();
// Compute the real number of Java fields
int java_fields = ikh()->java_fields_count();
write_u2(java_fields);
for (JavaFieldStream fs(ikh()); !fs.done(); fs.next()) {
AccessFlags access_flags = fs.access_flags();
int name_index = fs.name_index();
int signature_index = fs.signature_index();
int initial_value_index = fs.initval_index();
guarantee(name_index != 0 && signature_index != 0, "bad constant pool index for field");
// int offset = ikh()->field_offset( index );
int generic_signature_index = fs.generic_signature_index();
AnnotationArray* anno = fields_anno == NULL ? NULL : fields_anno->at(fs.index());
// JVMSpec| field_info {
// JVMSpec| u2 access_flags;
// JVMSpec| u2 name_index;
// JVMSpec| u2 descriptor_index;
// JVMSpec| u2 attributes_count;
// JVMSpec| attribute_info attributes[attributes_count];
// JVMSpec| }
write_u2(access_flags.as_int() & JVM_RECOGNIZED_FIELD_MODIFIERS);
write_u2(name_index);
write_u2(signature_index);
int attr_count = 0;
if (initial_value_index != 0) {
++attr_count;
}
if (access_flags.is_synthetic()) {
// ++attr_count;
}
if (generic_signature_index != 0) {
++attr_count;
}
if (anno != NULL) {
++attr_count; // has RuntimeVisibleAnnotations attribute
}
write_u2(attr_count);
if (initial_value_index != 0) {
write_attribute_name_index("ConstantValue");
write_u4(2); //length always 2
write_u2(initial_value_index);
}
if (access_flags.is_synthetic()) {
// write_synthetic_attribute();
}
if (generic_signature_index != 0) {
write_signature_attribute(generic_signature_index);
}
if (anno != NULL) {
write_annotations_attribute("RuntimeVisibleAnnotations", anno);
}
}
}
// Write Code attribute
// JVMSpec| Code_attribute {
// JVMSpec| u2 attribute_name_index;
// JVMSpec| u4 attribute_length;
// JVMSpec| u2 max_stack;
// JVMSpec| u2 max_locals;
// JVMSpec| u4 code_length;
// JVMSpec| u1 code[code_length];
// JVMSpec| u2 exception_table_length;
// JVMSpec| { u2 start_pc;
// JVMSpec| u2 end_pc;
// JVMSpec| u2 handler_pc;
// JVMSpec| u2 catch_type;
// JVMSpec| } exception_table[exception_table_length];
// JVMSpec| u2 attributes_count;
// JVMSpec| attribute_info attributes[attributes_count];
// JVMSpec| }
void JvmtiClassFileReconstituter::write_code_attribute(methodHandle method) {
ConstMethod* const_method = method->constMethod();
u2 line_num_cnt = 0;
int stackmap_len = 0;
int local_variable_table_length = 0;
int local_variable_type_table_length = 0;
// compute number and length of attributes
int attr_count = 0;
int attr_size = 0;
if (const_method->has_linenumber_table()) {
line_num_cnt = line_number_table_entries(method);
if (line_num_cnt != 0) {
++attr_count;
// Compute the complete size of the line number table attribute:
// LineNumberTable_attribute {
// u2 attribute_name_index;
// u4 attribute_length;
// u2 line_number_table_length;
// { u2 start_pc;
// u2 line_number;
// } line_number_table[line_number_table_length];
// }
attr_size += 2 + 4 + 2 + line_num_cnt * (2 + 2);
}
}
if (method->has_stackmap_table()) {
stackmap_len = method->stackmap_data()->length();
if (stackmap_len != 0) {
++attr_count;
// Compute the size of the stack map table attribute (VM stores raw):
// StackMapTable_attribute {
// u2 attribute_name_index;
// u4 attribute_length;
// u2 number_of_entries;
// stack_map_frame_entries[number_of_entries];
// }
attr_size += 2 + 4 + stackmap_len;
}
}
if (method->has_localvariable_table()) {
local_variable_table_length = method->localvariable_table_length();
if (local_variable_table_length != 0) {
++attr_count;
// Compute the size of the local variable table attribute (VM stores raw):
// LocalVariableTable_attribute {
// u2 attribute_name_index;
// u4 attribute_length;
// u2 local_variable_table_length;
// {
// u2 start_pc;
// u2 length;
// u2 name_index;
// u2 descriptor_index;
// u2 index;
// }
attr_size += 2 + 4 + 2 + local_variable_table_length * (2 + 2 + 2 + 2 + 2);
// Local variables with generic signatures must have LVTT entries
LocalVariableTableElement *elem = method->localvariable_table_start();
for (int idx = 0; idx < local_variable_table_length; idx++) {
if (elem[idx].signature_cp_index != 0) {
local_variable_type_table_length++;
}
}
if (local_variable_type_table_length != 0) {
++attr_count;
// Compute the size of the local variable type table attribute (VM stores raw):
// LocalVariableTypeTable_attribute {
// u2 attribute_name_index;
// u4 attribute_length;
// u2 local_variable_type_table_length;
// {
// u2 start_pc;
// u2 length;
// u2 name_index;
// u2 signature_index;
// u2 index;
// }
attr_size += 2 + 4 + 2 + local_variable_type_table_length * (2 + 2 + 2 + 2 + 2);
}
}
}
ExceptionTable exception_table(method());
int exception_table_length = exception_table.length();
int code_size = const_method->code_size();
int size =
2+2+4 + // max_stack, max_locals, code_length
code_size + // code
2 + // exception_table_length
(2+2+2+2) * exception_table_length + // exception_table
2 + // attributes_count
attr_size; // attributes
write_attribute_name_index("Code");
write_u4(size);
write_u2(method->verifier_max_stack());
write_u2(method->max_locals());
write_u4(code_size);
copy_bytecodes(method, (unsigned char*)writeable_address(code_size));
write_u2(exception_table_length);
for (int index = 0; index < exception_table_length; index++) {
write_u2(exception_table.start_pc(index));
write_u2(exception_table.end_pc(index));
write_u2(exception_table.handler_pc(index));
write_u2(exception_table.catch_type_index(index));
}
write_u2(attr_count);
if (line_num_cnt != 0) {
write_line_number_table_attribute(method, line_num_cnt);
}
if (stackmap_len != 0) {
write_stackmap_table_attribute(method, stackmap_len);
}
if (local_variable_table_length != 0) {
write_local_variable_table_attribute(method, local_variable_table_length);
}
if (local_variable_type_table_length != 0) {
write_local_variable_type_table_attribute(method, local_variable_type_table_length);
}
}
// Write Exceptions attribute
// JVMSpec| Exceptions_attribute {
// JVMSpec| u2 attribute_name_index;
// JVMSpec| u4 attribute_length;
// JVMSpec| u2 number_of_exceptions;
// JVMSpec| u2 exception_index_table[number_of_exceptions];
// JVMSpec| }
void JvmtiClassFileReconstituter::write_exceptions_attribute(ConstMethod* const_method) {
CheckedExceptionElement* checked_exceptions = const_method->checked_exceptions_start();
int checked_exceptions_length = const_method->checked_exceptions_length();
int size =
2 + // number_of_exceptions
2 * checked_exceptions_length; // exception_index_table
write_attribute_name_index("Exceptions");
write_u4(size);
write_u2(checked_exceptions_length);
for (int index = 0; index < checked_exceptions_length; index++) {
write_u2(checked_exceptions[index].class_cp_index);
}
}
// Write SourceFile attribute
// JVMSpec| SourceFile_attribute {
// JVMSpec| u2 attribute_name_index;
// JVMSpec| u4 attribute_length;
// JVMSpec| u2 sourcefile_index;
// JVMSpec| }
void JvmtiClassFileReconstituter::write_source_file_attribute() {
assert(ikh()->source_file_name() != NULL, "caller must check");
write_attribute_name_index("SourceFile");
write_u4(2); // always length 2
write_u2(symbol_to_cpool_index(ikh()->source_file_name()));
}
// Write SourceDebugExtension attribute
// JSR45| SourceDebugExtension_attribute {
// JSR45| u2 attribute_name_index;
// JSR45| u4 attribute_length;
// JSR45| u1 debug_extension[attribute_length];
// JSR45| }
void JvmtiClassFileReconstituter::write_source_debug_extension_attribute() {
assert(ikh()->source_debug_extension() != NULL, "caller must check");
write_attribute_name_index("SourceDebugExtension");
int len = (int)strlen(ikh()->source_debug_extension());
write_u4(len);
u1* ext = (u1*)ikh()->source_debug_extension();
for (int i=0; i<len; i++) {
write_u1(ext[i]);
}
}
// Write (generic) Signature attribute
// JVMSpec| Signature_attribute {
// JVMSpec| u2 attribute_name_index;
// JVMSpec| u4 attribute_length;
// JVMSpec| u2 signature_index;
// JVMSpec| }
void JvmtiClassFileReconstituter::write_signature_attribute(u2 generic_signature_index) {
write_attribute_name_index("Signature");
write_u4(2); // always length 2
write_u2(generic_signature_index);
}
// Compute the number of entries in the InnerClasses attribute
u2 JvmtiClassFileReconstituter::inner_classes_attribute_length() {
InnerClassesIterator iter(ikh());
return iter.length();
}
// Write an annotation attribute. The VM stores them in raw form, so all we need
// to do is add the attrubute name and fill in the length.
// JSR202| *Annotations_attribute {
// JSR202| u2 attribute_name_index;
// JSR202| u4 attribute_length;
// JSR202| ...
// JSR202| }
void JvmtiClassFileReconstituter::write_annotations_attribute(const char* attr_name,
AnnotationArray* annos) {
u4 length = annos->length();
write_attribute_name_index(attr_name);
write_u4(length);
memcpy(writeable_address(length), annos->adr_at(0), length);
}
// BootstrapMethods_attribute {
// u2 attribute_name_index;
// u4 attribute_length;
// u2 num_bootstrap_methods;
// { u2 bootstrap_method_ref;
// u2 num_bootstrap_arguments;
// u2 bootstrap_arguments[num_bootstrap_arguments];
// } bootstrap_methods[num_bootstrap_methods];
// }
void JvmtiClassFileReconstituter::write_bootstrapmethod_attribute() {
Array<u2>* operands = cpool()->operands();
write_attribute_name_index("BootstrapMethods");
int num_bootstrap_methods = ConstantPool::operand_array_length(operands);
// calculate length of attribute
int length = sizeof(u2); // num_bootstrap_methods
for (int n = 0; n < num_bootstrap_methods; n++) {
u2 num_bootstrap_arguments = cpool()->operand_argument_count_at(n);
length += sizeof(u2); // bootstrap_method_ref
length += sizeof(u2); // num_bootstrap_arguments
length += sizeof(u2) * num_bootstrap_arguments; // bootstrap_arguments[num_bootstrap_arguments]
}
write_u4(length);
// write attribute
write_u2(num_bootstrap_methods);
for (int n = 0; n < num_bootstrap_methods; n++) {
u2 bootstrap_method_ref = cpool()->operand_bootstrap_method_ref_index_at(n);
u2 num_bootstrap_arguments = cpool()->operand_argument_count_at(n);
write_u2(bootstrap_method_ref);
write_u2(num_bootstrap_arguments);
for (int arg = 0; arg < num_bootstrap_arguments; arg++) {
u2 bootstrap_argument = cpool()->operand_argument_index_at(n, arg);
write_u2(bootstrap_argument);
}
}
}
// Write InnerClasses attribute
// JVMSpec| InnerClasses_attribute {
// JVMSpec| u2 attribute_name_index;
// JVMSpec| u4 attribute_length;
// JVMSpec| u2 number_of_classes;
// JVMSpec| { u2 inner_class_info_index;
// JVMSpec| u2 outer_class_info_index;
// JVMSpec| u2 inner_name_index;
// JVMSpec| u2 inner_class_access_flags;
// JVMSpec| } classes[number_of_classes];
// JVMSpec| }
void JvmtiClassFileReconstituter::write_inner_classes_attribute(int length) {
InnerClassesIterator iter(ikh());
guarantee(iter.length() != 0 && iter.length() == length,
"caller must check");
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 (; !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());
}
}
// Write Synthetic attribute
// JVMSpec| Synthetic_attribute {
// JVMSpec| u2 attribute_name_index;
// JVMSpec| u4 attribute_length;
// JVMSpec| }
void JvmtiClassFileReconstituter::write_synthetic_attribute() {
write_attribute_name_index("Synthetic");
write_u4(0); //length always zero
}
// Compute size of LineNumberTable
u2 JvmtiClassFileReconstituter::line_number_table_entries(methodHandle method) {
// The line number table is compressed so we don't know how big it is until decompressed.
// Decompression is really fast so we just do it twice.
u2 num_entries = 0;
CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
while (stream.read_pair()) {
num_entries++;
}
return num_entries;
}
// Write LineNumberTable attribute
// JVMSpec| LineNumberTable_attribute {
// JVMSpec| u2 attribute_name_index;
// JVMSpec| u4 attribute_length;
// JVMSpec| u2 line_number_table_length;
// JVMSpec| { u2 start_pc;
// JVMSpec| u2 line_number;
// JVMSpec| } line_number_table[line_number_table_length];
// JVMSpec| }
void JvmtiClassFileReconstituter::write_line_number_table_attribute(methodHandle method,
u2 num_entries) {
write_attribute_name_index("LineNumberTable");
write_u4(2 + num_entries * (2 + 2));
write_u2(num_entries);
CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
while (stream.read_pair()) {
write_u2(stream.bci());
write_u2(stream.line());
}
}
// Write LocalVariableTable attribute
// JVMSpec| LocalVariableTable_attribute {
// JVMSpec| u2 attribute_name_index;
// JVMSpec| u4 attribute_length;
// JVMSpec| u2 local_variable_table_length;
// JVMSpec| { u2 start_pc;
// JVMSpec| u2 length;
// JVMSpec| u2 name_index;
// JVMSpec| u2 descriptor_index;
// JVMSpec| u2 index;
// JVMSpec| } local_variable_table[local_variable_table_length];
// JVMSpec| }
void JvmtiClassFileReconstituter::write_local_variable_table_attribute(methodHandle method, u2 num_entries) {
write_attribute_name_index("LocalVariableTable");
write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
write_u2(num_entries);
assert(method->localvariable_table_length() == num_entries, "just checking");
LocalVariableTableElement *elem = method->localvariable_table_start();
for (int j=0; j<method->localvariable_table_length(); j++) {
write_u2(elem->start_bci);
write_u2(elem->length);
write_u2(elem->name_cp_index);
write_u2(elem->descriptor_cp_index);
write_u2(elem->slot);
elem++;
}
}
// Write LocalVariableTypeTable attribute
// JVMSpec| LocalVariableTypeTable_attribute {
// JVMSpec| u2 attribute_name_index;
// JVMSpec| u4 attribute_length;
// JVMSpec| u2 local_variable_type_table_length;
// JVMSpec| { u2 start_pc;
// JVMSpec| u2 length;
// JVMSpec| u2 name_index;
// JVMSpec| u2 signature_index;
// JVMSpec| u2 index;
// JVMSpec| } local_variable_type_table[local_variable_type_table_length];
// JVMSpec| }
void JvmtiClassFileReconstituter::write_local_variable_type_table_attribute(methodHandle method, u2 num_entries) {
write_attribute_name_index("LocalVariableTypeTable");
write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
write_u2(num_entries);
LocalVariableTableElement *elem = method->localvariable_table_start();
for (int j=0; j<method->localvariable_table_length(); j++) {
if (elem->signature_cp_index > 0) {
// Local variable has a generic signature - write LVTT attribute entry
write_u2(elem->start_bci);
write_u2(elem->length);
write_u2(elem->name_cp_index);
write_u2(elem->signature_cp_index);
write_u2(elem->slot);
num_entries--;
}
elem++;
}
assert(num_entries == 0, "just checking");
}
// Write stack map table attribute
// JSR-202| StackMapTable_attribute {
// JSR-202| u2 attribute_name_index;
// JSR-202| u4 attribute_length;
// JSR-202| u2 number_of_entries;
// JSR-202| stack_map_frame_entries[number_of_entries];
// JSR-202| }
void JvmtiClassFileReconstituter::write_stackmap_table_attribute(methodHandle method,
int stackmap_len) {
write_attribute_name_index("StackMapTable");
write_u4(stackmap_len);
memcpy(
writeable_address(stackmap_len),
(void*)(method->stackmap_data()->adr_at(0)),
stackmap_len);
}
// Write one method_info structure
// JVMSpec| method_info {
// JVMSpec| u2 access_flags;
// JVMSpec| u2 name_index;
// JVMSpec| u2 descriptor_index;
// JVMSpec| u2 attributes_count;
// JVMSpec| attribute_info attributes[attributes_count];
// JVMSpec| }
void JvmtiClassFileReconstituter::write_method_info(methodHandle method) {
AccessFlags access_flags = method->access_flags();
ConstMethod* const_method = method->constMethod();
u2 generic_signature_index = const_method->generic_signature_index();
AnnotationArray* anno = method->annotations();
AnnotationArray* param_anno = method->parameter_annotations();
AnnotationArray* default_anno = method->annotation_default();
// skip generated default interface methods
if (method->is_overpass()) {
return;
}
write_u2(access_flags.get_flags() & JVM_RECOGNIZED_METHOD_MODIFIERS);
write_u2(const_method->name_index());
write_u2(const_method->signature_index());
// write attributes in the same order javac does, so we can test with byte for
// byte comparison
int attr_count = 0;
if (const_method->code_size() != 0) {
++attr_count; // has Code attribute
}
if (const_method->has_checked_exceptions()) {
++attr_count; // has Exceptions attribute
}
if (default_anno != NULL) {
++attr_count; // has AnnotationDefault attribute
}
// Deprecated attribute would go here
if (access_flags.is_synthetic()) { // FIXME
// ++attr_count;
}
if (generic_signature_index != 0) {
++attr_count;
}
if (anno != NULL) {
++attr_count; // has RuntimeVisibleAnnotations attribute
}
if (param_anno != NULL) {
++attr_count; // has RuntimeVisibleParameterAnnotations attribute
}
write_u2(attr_count);
if (const_method->code_size() > 0) {
write_code_attribute(method);
}
if (const_method->has_checked_exceptions()) {
write_exceptions_attribute(const_method);
}
if (default_anno != NULL) {
write_annotations_attribute("AnnotationDefault", default_anno);
}
// Deprecated attribute would go here
if (access_flags.is_synthetic()) {
// write_synthetic_attribute();
}
if (generic_signature_index != 0) {
write_signature_attribute(generic_signature_index);
}
if (anno != NULL) {
write_annotations_attribute("RuntimeVisibleAnnotations", anno);
}
if (param_anno != NULL) {
write_annotations_attribute("RuntimeVisibleParameterAnnotations", param_anno);
}
}
// Write the class attributes portion of ClassFile structure
// JVMSpec| u2 attributes_count;
// JVMSpec| attribute_info attributes[attributes_count];
void JvmtiClassFileReconstituter::write_class_attributes() {
u2 inner_classes_length = inner_classes_attribute_length();
Symbol* generic_signature = ikh()->generic_signature();
AnnotationArray* anno = ikh()->class_annotations();
int attr_count = 0;
if (generic_signature != NULL) {
++attr_count;
}
if (ikh()->source_file_name() != NULL) {
++attr_count;
}
if (ikh()->source_debug_extension() != NULL) {
++attr_count;
}
if (inner_classes_length > 0) {
++attr_count;
}
if (anno != NULL) {
++attr_count; // has RuntimeVisibleAnnotations attribute
}
if (cpool()->operands() != NULL) {
++attr_count;
}
write_u2(attr_count);
if (generic_signature != NULL) {
write_signature_attribute(symbol_to_cpool_index(generic_signature));
}
if (ikh()->source_file_name() != NULL) {
write_source_file_attribute();
}
if (ikh()->source_debug_extension() != NULL) {
write_source_debug_extension_attribute();
}
if (inner_classes_length > 0) {
write_inner_classes_attribute(inner_classes_length);
}
if (anno != NULL) {
write_annotations_attribute("RuntimeVisibleAnnotations", anno);
}
if (cpool()->operands() != NULL) {
write_bootstrapmethod_attribute();
}
}
// Write the method information portion of ClassFile structure
// JVMSpec| u2 methods_count;
// JVMSpec| method_info methods[methods_count];
void JvmtiClassFileReconstituter::write_method_infos() {
HandleMark hm(thread());
Array<Method*>* methods = ikh()->methods();
int num_methods = methods->length();
int num_overpass = 0;
// count the generated default interface methods
// these will not be re-created by write_method_info
// and should not be included in the total count
for (int index = 0; index < num_methods; index++) {
Method* method = methods->at(index);
if (method->is_overpass()) {
num_overpass++;
}
}
write_u2(num_methods - num_overpass);
if (JvmtiExport::can_maintain_original_method_order()) {
int index;
int original_index;
intArray method_order(num_methods, 0);
// invert the method order mapping
for (index = 0; index < num_methods; index++) {
original_index = ikh()->method_ordering()->at(index);
assert(original_index >= 0 && original_index < num_methods,
"invalid original method index");
method_order.at_put(original_index, index);
}
// write in original order
for (original_index = 0; original_index < num_methods; original_index++) {
index = method_order.at(original_index);
methodHandle method(thread(), methods->at(index));
write_method_info(method);
}
} else {
// method order not preserved just dump the method infos
for (int index = 0; index < num_methods; index++) {
methodHandle method(thread(), methods->at(index));
write_method_info(method);
}
}
}
void JvmtiClassFileReconstituter::write_class_file_format() {
ReallocMark();
// JVMSpec| ClassFile {
// JVMSpec| u4 magic;
write_u4(0xCAFEBABE);
// JVMSpec| u2 minor_version;
// JVMSpec| u2 major_version;
write_u2(ikh()->minor_version());
u2 major = ikh()->major_version();
write_u2(major);
// JVMSpec| u2 constant_pool_count;
// JVMSpec| cp_info constant_pool[constant_pool_count-1];
write_u2(cpool()->length());
copy_cpool_bytes(writeable_address(cpool_size()));
// JVMSpec| u2 access_flags;
write_u2(ikh()->access_flags().get_flags() & JVM_RECOGNIZED_CLASS_MODIFIERS);
// JVMSpec| u2 this_class;
// JVMSpec| u2 super_class;
write_u2(class_symbol_to_cpool_index(ikh()->name()));
Klass* super_class = ikh()->super();
write_u2(super_class == NULL? 0 : // zero for java.lang.Object
class_symbol_to_cpool_index(super_class->name()));
// JVMSpec| u2 interfaces_count;
// JVMSpec| u2 interfaces[interfaces_count];
Array<Klass*>* interfaces = ikh()->local_interfaces();
int num_interfaces = interfaces->length();
write_u2(num_interfaces);
for (int index = 0; index < num_interfaces; index++) {
HandleMark hm(thread());
instanceKlassHandle iikh(thread(), interfaces->at(index));
write_u2(class_symbol_to_cpool_index(iikh->name()));
}
// JVMSpec| u2 fields_count;
// JVMSpec| field_info fields[fields_count];
write_field_infos();
// JVMSpec| u2 methods_count;
// JVMSpec| method_info methods[methods_count];
write_method_infos();
// JVMSpec| u2 attributes_count;
// JVMSpec| attribute_info attributes[attributes_count];
// JVMSpec| } /* end ClassFile 8?
write_class_attributes();
}
address JvmtiClassFileReconstituter::writeable_address(size_t size) {
size_t used_size = _buffer_ptr - _buffer;
if (size + used_size >= _buffer_size) {
// compute the new buffer size: must be at least twice as big as before
// plus whatever new is being used; then convert to nice clean block boundary
size_t new_buffer_size = (size + _buffer_size*2 + 1) / initial_buffer_size
* initial_buffer_size;
// VM goes belly-up if the memory isn't available, so cannot do OOM processing
_buffer = REALLOC_RESOURCE_ARRAY(u1, _buffer, _buffer_size, new_buffer_size);
_buffer_size = new_buffer_size;
_buffer_ptr = _buffer + used_size;
}
u1* ret_ptr = _buffer_ptr;
_buffer_ptr += size;
return ret_ptr;
}
void JvmtiClassFileReconstituter::write_attribute_name_index(const char* name) {
TempNewSymbol sym = SymbolTable::probe(name, (int)strlen(name));
assert(sym != NULL, "attribute name symbol not found");
u2 attr_name_index = symbol_to_cpool_index(sym);
assert(attr_name_index != 0, "attribute name symbol not in constant pool");
write_u2(attr_name_index);
}
void JvmtiClassFileReconstituter::write_u1(u1 x) {
*writeable_address(1) = x;
}
void JvmtiClassFileReconstituter::write_u2(u2 x) {
Bytes::put_Java_u2(writeable_address(2), x);
}
void JvmtiClassFileReconstituter::write_u4(u4 x) {
Bytes::put_Java_u4(writeable_address(4), x);
}
void JvmtiClassFileReconstituter::write_u8(u8 x) {
Bytes::put_Java_u8(writeable_address(8), x);
}
void JvmtiClassFileReconstituter::copy_bytecodes(methodHandle mh,
unsigned char* bytecodes) {
// use a BytecodeStream to iterate over the bytecodes. JVM/fast bytecodes
// and the breakpoint bytecode are converted to their original bytecodes.
BytecodeStream bs(mh);
unsigned char* p = bytecodes;
Bytecodes::Code code;
bool is_rewritten = mh->method_holder()->is_rewritten();
while ((code = bs.next()) >= 0) {
assert(Bytecodes::is_java_code(code), "sanity check");
assert(code != Bytecodes::_breakpoint, "sanity check");
// length of bytecode (mnemonic + operands)
address bcp = bs.bcp();
int len = bs.instruction_size();
assert(len > 0, "length must be > 0");
// copy the bytecodes
*p = (unsigned char) (bs.is_wide()? Bytecodes::_wide : code);
if (len > 1) {
memcpy(p+1, bcp+1, len-1);
}
// During linking the get/put and invoke instructions are rewritten
// with an index into the constant pool cache. The original constant
// pool index must be returned to caller. Rewrite the index.
if (is_rewritten && len > 1) {
bool is_wide = false;
switch (code) {
case Bytecodes::_getstatic : // fall through
case Bytecodes::_putstatic : // fall through
case Bytecodes::_getfield : // fall through
case Bytecodes::_putfield : // fall through
case Bytecodes::_invokevirtual : // fall through
case Bytecodes::_invokespecial : // fall through
case Bytecodes::_invokestatic : // fall through
case Bytecodes::_invokedynamic : // fall through
case Bytecodes::_invokeinterface : {
assert(len == 3 ||
(code == Bytecodes::_invokeinterface && len == 5) ||
(code == Bytecodes::_invokedynamic && len == 5),
"sanity check");
int cpci = Bytes::get_native_u2(bcp+1);
bool is_invokedynamic = (EnableInvokeDynamic && code == Bytecodes::_invokedynamic);
ConstantPoolCacheEntry* entry;
if (is_invokedynamic) {
cpci = Bytes::get_native_u4(bcp+1);
entry = mh->constants()->invokedynamic_cp_cache_entry_at(cpci);
} else {
// cache cannot be pre-fetched since some classes won't have it yet
entry = mh->constants()->cache()->entry_at(cpci);
}
int i = entry->constant_pool_index();
assert(i < mh->constants()->length(), "sanity check");
Bytes::put_Java_u2((address)(p+1), (u2)i); // java byte ordering
if (is_invokedynamic) *(p+3) = *(p+4) = 0;
break;
}
case Bytecodes::_ldc_w:
is_wide = true; // fall through
case Bytecodes::_ldc: {
if (bs.raw_code() == Bytecodes::_fast_aldc || bs.raw_code() == Bytecodes::_fast_aldc_w) {
int cpci = is_wide ? Bytes::get_native_u2(bcp+1) : (u1)(*(bcp+1));
int i = mh->constants()->object_to_cp_index(cpci);
assert(i < mh->constants()->length(), "sanity check");
if (is_wide) {
Bytes::put_Java_u2((address)(p+1), (u2)i); // java byte ordering
} else {
*(p+1) = (u1)i;
}
}
break;
}
}
}
p += len;
}
}
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