JDK14/Java14源码在线阅读
/*
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* 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.
*
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* 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.
*
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#include "precompiled.hpp"
#include "classfile/resolutionErrors.hpp"
#include "interpreter/bytecodeStream.hpp"
#include "interpreter/bytecodes.hpp"
#include "interpreter/interpreter.hpp"
#include "interpreter/linkResolver.hpp"
#include "interpreter/rewriter.hpp"
#include "logging/log.hpp"
#include "memory/heapShared.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/metaspaceClosure.hpp"
#include "memory/metaspaceShared.hpp"
#include "memory/resourceArea.hpp"
#include "oops/access.inline.hpp"
#include "oops/compressedOops.hpp"
#include "oops/constantPool.inline.hpp"
#include "oops/cpCache.inline.hpp"
#include "oops/objArrayOop.inline.hpp"
#include "oops/oop.inline.hpp"
#include "prims/methodHandles.hpp"
#include "runtime/atomic.hpp"
#include "runtime/handles.inline.hpp"
#include "utilities/macros.hpp"
// Implementation of ConstantPoolCacheEntry
void ConstantPoolCacheEntry::initialize_entry(int index) {
assert(0 < index && index < 0x10000, "sanity check");
_indices = index;
_f1 = NULL;
_f2 = _flags = 0;
assert(constant_pool_index() == index, "");
}
void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) {
assert((_indices & (~cp_index_mask)) == 0, "sanity");
assert(_f1 == NULL, "sanity");
assert(_flags == 0, "sanity");
if (!f2_used) {
assert(_f2 == 0, "sanity");
}
}
void ConstantPoolCacheEntry::reinitialize(bool f2_used) {
_indices &= cp_index_mask;
_f1 = NULL;
_flags = 0;
if (!f2_used) {
_f2 = 0;
}
}
int ConstantPoolCacheEntry::make_flags(TosState state,
int option_bits,
int field_index_or_method_params) {
assert(state < number_of_states, "Invalid state in make_flags");
int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params;
// Preserve existing flag bit values
// The low bits are a field offset, or else the method parameter size.
#ifdef ASSERT
TosState old_state = flag_state();
assert(old_state == (TosState)0 || old_state == state,
"inconsistent cpCache flags state");
#endif
return (_flags | f) ;
}
void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
#ifdef ASSERT
// Read once.
volatile Bytecodes::Code c = bytecode_1();
assert(c == 0 || c == code || code == 0, "update must be consistent");
#endif
// Need to flush pending stores here before bytecode is written.
Atomic::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift));
}
void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
#ifdef ASSERT
// Read once.
volatile Bytecodes::Code c = bytecode_2();
assert(c == 0 || c == code || code == 0, "update must be consistent");
#endif
// Need to flush pending stores here before bytecode is written.
Atomic::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift));
}
// Sets f1, ordering with previous writes.
void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) {
assert(f1 != NULL, "");
Atomic::release_store(&_f1, f1);
}
void ConstantPoolCacheEntry::set_indy_resolution_failed() {
Atomic::release_store(&_flags, _flags | (1 << indy_resolution_failed_shift));
}
// Note that concurrent update of both bytecodes can leave one of them
// reset to zero. This is harmless; the interpreter will simply re-resolve
// the damaged entry. More seriously, the memory synchronization is needed
// to flush other fields (f1, f2) completely to memory before the bytecodes
// are updated, lest other processors see a non-zero bytecode but zero f1/f2.
void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
Bytecodes::Code put_code,
Klass* field_holder,
int field_index,
int field_offset,
TosState field_type,
bool is_final,
bool is_volatile,
Klass* root_klass) {
set_f1(field_holder);
set_f2(field_offset);
assert((field_index & field_index_mask) == field_index,
"field index does not fit in low flag bits");
set_field_flags(field_type,
((is_volatile ? 1 : 0) << is_volatile_shift) |
((is_final ? 1 : 0) << is_final_shift),
field_index);
set_bytecode_1(get_code);
set_bytecode_2(put_code);
NOT_PRODUCT(verify(tty));
}
void ConstantPoolCacheEntry::set_parameter_size(int value) {
// This routine is called only in corner cases where the CPCE is not yet initialized.
// See AbstractInterpreter::deopt_continue_after_entry.
assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
"size must not change: parameter_size=%d, value=%d", parameter_size(), value);
// Setting the parameter size by itself is only safe if the
// current value of _flags is 0, otherwise another thread may have
// updated it and we don't want to overwrite that value. Don't
// bother trying to update it once it's nonzero but always make
// sure that the final parameter size agrees with what was passed.
if (_flags == 0) {
intx newflags = (value & parameter_size_mask);
Atomic::cmpxchg(&_flags, (intx)0, newflags);
}
guarantee(parameter_size() == value,
"size must not change: parameter_size=%d, value=%d", parameter_size(), value);
}
void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
const methodHandle& method,
int vtable_index,
bool sender_is_interface) {
bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean
assert(method->interpreter_entry() != NULL, "should have been set at this point");
assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
int byte_no = -1;
bool change_to_virtual = false;
InstanceKlass* holder = NULL; // have to declare this outside the switch
switch (invoke_code) {
case Bytecodes::_invokeinterface:
holder = method->method_holder();
// check for private interface method invocations
if (vtable_index == Method::nonvirtual_vtable_index && holder->is_interface() ) {
assert(method->is_private(), "unexpected non-private method");
assert(method->can_be_statically_bound(), "unexpected non-statically-bound method");
// set_f2_as_vfinal_method checks if is_vfinal flag is true.
set_method_flags(as_TosState(method->result_type()),
( 1 << is_vfinal_shift) |
((method->is_final_method() ? 1 : 0) << is_final_shift),
method()->size_of_parameters());
set_f2_as_vfinal_method(method());
byte_no = 2;
set_f1(holder); // interface klass*
break;
}
else {
// We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
// instruction links to a non-interface method (in Object). This can happen when
// an interface redeclares an Object method (like CharSequence declaring toString())
// or when invokeinterface is used explicitly.
// In that case, the method has no itable index and must be invoked as a virtual.
// Set a flag to keep track of this corner case.
assert(holder->is_interface() || holder == SystemDictionary::Object_klass(), "unexpected holder class");
assert(method->is_public(), "Calling non-public method in Object with invokeinterface");
change_to_virtual = true;
// ...and fall through as if we were handling invokevirtual:
}
case Bytecodes::_invokevirtual:
{
if (!is_vtable_call) {
assert(method->can_be_statically_bound(), "");
// set_f2_as_vfinal_method checks if is_vfinal flag is true.
set_method_flags(as_TosState(method->result_type()),
( 1 << is_vfinal_shift) |
((method->is_final_method() ? 1 : 0) << is_final_shift) |
((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
method()->size_of_parameters());
set_f2_as_vfinal_method(method());
} else {
assert(!method->can_be_statically_bound(), "");
assert(vtable_index >= 0, "valid index");
assert(!method->is_final_method(), "sanity");
set_method_flags(as_TosState(method->result_type()),
((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
method()->size_of_parameters());
set_f2(vtable_index);
}
byte_no = 2;
break;
}
case Bytecodes::_invokespecial:
case Bytecodes::_invokestatic:
assert(!is_vtable_call, "");
// Note: Read and preserve the value of the is_vfinal flag on any
// invokevirtual bytecode shared with this constant pool cache entry.
// It is cheap and safe to consult is_vfinal() at all times.
// Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
set_method_flags(as_TosState(method->result_type()),
((is_vfinal() ? 1 : 0) << is_vfinal_shift) |
((method->is_final_method() ? 1 : 0) << is_final_shift),
method()->size_of_parameters());
set_f1(method());
byte_no = 1;
break;
default:
ShouldNotReachHere();
break;
}
// Note: byte_no also appears in TemplateTable::resolve.
if (byte_no == 1) {
assert(invoke_code != Bytecodes::_invokevirtual &&
invoke_code != Bytecodes::_invokeinterface, "");
bool do_resolve = true;
// Don't mark invokespecial to method as resolved if sender is an interface. The receiver
// has to be checked that it is a subclass of the current class every time this bytecode
// is executed.
if (invoke_code == Bytecodes::_invokespecial && sender_is_interface &&
method->name() != vmSymbols::object_initializer_name()) {
do_resolve = false;
}
if (invoke_code == Bytecodes::_invokestatic) {
assert(method->method_holder()->is_initialized() ||
method->method_holder()->is_reentrant_initialization(Thread::current()),
"invalid class initialization state for invoke_static");
if (!VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
// Don't mark invokestatic to method as resolved if the holder class has not yet completed
// initialization. An invokestatic must only proceed if the class is initialized, but if
// we resolve it before then that class initialization check is skipped.
//
// When fast class initialization checks are supported (VM_Version::supports_fast_class_init_checks() == true),
// template interpreter supports fast class initialization check for
// invokestatic which doesn't require call site re-resolution to
// enforce class initialization barrier.
do_resolve = false;
}
}
if (do_resolve) {
set_bytecode_1(invoke_code);
}
} else if (byte_no == 2) {
if (change_to_virtual) {
assert(invoke_code == Bytecodes::_invokeinterface, "");
// NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
//
// Workaround for the case where we encounter an invokeinterface, but we
// should really have an _invokevirtual since the resolved method is a
// virtual method in java.lang.Object. This is a corner case in the spec
// but is presumably legal. javac does not generate this code.
//
// We do not set bytecode_1() to _invokeinterface, because that is the
// bytecode # used by the interpreter to see if it is resolved. In this
// case, the method gets reresolved with caller for each interface call
// because the actual selected method may not be public.
//
// We set bytecode_2() to _invokevirtual.
// See also interpreterRuntime.cpp. (8/25/2000)
} else {
assert(invoke_code == Bytecodes::_invokevirtual ||
(invoke_code == Bytecodes::_invokeinterface &&
((method->is_private() ||
(method->is_final() && method->method_holder() == SystemDictionary::Object_klass())))),
"unexpected invocation mode");
if (invoke_code == Bytecodes::_invokeinterface &&
(method->is_private() || method->is_final())) {
// We set bytecode_1() to _invokeinterface, because that is the
// bytecode # used by the interpreter to see if it is resolved.
// We set bytecode_2() to _invokevirtual.
set_bytecode_1(invoke_code);
}
}
// set up for invokevirtual, even if linking for invokeinterface also:
set_bytecode_2(Bytecodes::_invokevirtual);
} else {
ShouldNotReachHere();
}
NOT_PRODUCT(verify(tty));
}
void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
bool sender_is_interface) {
int index = Method::nonvirtual_vtable_index;
// index < 0; FIXME: inline and customize set_direct_or_vtable_call
set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface);
}
void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
// either the method is a miranda or its holder should accept the given index
assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
// index >= 0; FIXME: inline and customize set_direct_or_vtable_call
set_direct_or_vtable_call(invoke_code, method, index, false);
}
void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code,
Klass* referenced_klass,
const methodHandle& method, int index) {
assert(method->method_holder()->verify_itable_index(index), "");
assert(invoke_code == Bytecodes::_invokeinterface, "");
InstanceKlass* interf = method->method_holder();
assert(interf->is_interface(), "must be an interface");
assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
set_f1(referenced_klass);
set_f2((intx)method());
set_method_flags(as_TosState(method->result_type()),
0, // no option bits
method()->size_of_parameters());
set_bytecode_1(Bytecodes::_invokeinterface);
}
void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
}
void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
}
void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
Bytecodes::Code invoke_code,
const CallInfo &call_info) {
// NOTE: This CPCE can be the subject of data races.
// There are three words to update: flags, refs[f2], f1 (in that order).
// Writers must store all other values before f1.
// Readers must test f1 first for non-null before reading other fields.
// Competing writers must acquire exclusive access via a lock.
// A losing writer waits on the lock until the winner writes f1 and leaves
// the lock, so that when the losing writer returns, he can use the linked
// cache entry.
objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
// Use the resolved_references() lock for this cpCache entry.
// resolved_references are created for all classes with Invokedynamic, MethodHandle
// or MethodType constant pool cache entries.
assert(resolved_references() != NULL,
"a resolved_references array should have been created for this class");
ObjectLocker ol(resolved_references, Thread::current());
if (!is_f1_null()) {
return;
}
if (indy_resolution_failed()) {
// Before we got here, another thread got a LinkageError exception during
// resolution. Ignore our success and throw their exception.
ConstantPoolCache* cpCache = cpool->cache();
int index = -1;
for (int i = 0; i < cpCache->length(); i++) {
if (cpCache->entry_at(i) == this) {
index = i;
break;
}
}
guarantee(index >= 0, "Didn't find cpCache entry!");
int encoded_index = ResolutionErrorTable::encode_cpcache_index(
ConstantPool::encode_invokedynamic_index(index));
Thread* THREAD = Thread::current();
ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
return;
}
Method* adapter = call_info.resolved_method();
const Handle appendix = call_info.resolved_appendix();
const bool has_appendix = appendix.not_null();
// Write the flags.
// MHs and indy are always sig-poly and have a local signature.
set_method_flags(as_TosState(adapter->result_type()),
((has_appendix ? 1 : 0) << has_appendix_shift ) |
( 1 << has_local_signature_shift ) |
( 1 << is_final_shift ),
adapter->size_of_parameters());
if (TraceInvokeDynamic) {
ttyLocker ttyl;
tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method=" PTR_FORMAT " (local signature) ",
invoke_code,
p2i(appendix()),
(has_appendix ? "" : " (unused)"),
p2i(adapter));
adapter->print();
if (has_appendix) appendix()->print();
}
// Method handle invokes and invokedynamic sites use both cp cache words.
// refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
// In the general case, this could be the call site's MethodType,
// for use with java.lang.Invokers.checkExactType, or else a CallSite object.
// f1 contains the adapter method which manages the actual call.
// In the general case, this is a compiled LambdaForm.
// (The Java code is free to optimize these calls by binding other
// sorts of methods and appendices to call sites.)
// JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
// The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
// Even with the appendix, the method will never take more than 255 parameter slots.
//
// This means that given a call site like (List)mh.invoke("foo"),
// the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
// not '(Ljava/lang/String;)Ljava/util/List;'.
// The fact that String and List are involved is encoded in the MethodType in refs[f2].
// This allows us to create fewer Methods, while keeping type safety.
//
// Store appendix, if any.
if (has_appendix) {
const int appendix_index = f2_as_index();
assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
resolved_references->obj_at_put(appendix_index, appendix());
}
release_set_f1(adapter); // This must be the last one to set (see NOTE above)!
// The interpreter assembly code does not check byte_2,
// but it is used by is_resolved, method_if_resolved, etc.
set_bytecode_1(invoke_code);
NOT_PRODUCT(verify(tty));
if (TraceInvokeDynamic) {
ttyLocker ttyl;
this->print(tty, 0);
}
assert(has_appendix == this->has_appendix(), "proper storage of appendix flag");
assert(this->has_local_signature(), "proper storage of signature flag");
}
bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
"No LinkageError exception");
// Use the resolved_references() lock for this cpCache entry.
// resolved_references are created for all classes with Invokedynamic, MethodHandle
// or MethodType constant pool cache entries.
objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
assert(resolved_references() != NULL,
"a resolved_references array should have been created for this class");
ObjectLocker ol(resolved_references, THREAD);
// if f1 is not null or the indy_resolution_failed flag is set then another
// thread either succeeded in resolving the method or got a LinkageError
// exception, before this thread was able to record its failure. So, clear
// this thread's exception and return false so caller can use the earlier
// thread's result.
if (!is_f1_null() || indy_resolution_failed()) {
CLEAR_PENDING_EXCEPTION;
return false;
}
Symbol* error = PENDING_EXCEPTION->klass()->name();
Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
SystemDictionary::add_resolution_error(cpool, index, error, message);
set_indy_resolution_failed();
return true;
}
Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
// Decode the action of set_method and set_interface_call
Bytecodes::Code invoke_code = bytecode_1();
if (invoke_code != (Bytecodes::Code)0) {
Metadata* f1 = f1_ord();
if (f1 != NULL) {
switch (invoke_code) {
case Bytecodes::_invokeinterface:
assert(f1->is_klass(), "");
return f2_as_interface_method();
case Bytecodes::_invokestatic:
case Bytecodes::_invokespecial:
assert(!has_appendix(), "");
case Bytecodes::_invokehandle:
case Bytecodes::_invokedynamic:
assert(f1->is_method(), "");
return (Method*)f1;
default:
break;
}
}
}
invoke_code = bytecode_2();
if (invoke_code != (Bytecodes::Code)0) {
switch (invoke_code) {
case Bytecodes::_invokevirtual:
if (is_vfinal()) {
// invokevirtual
Method* m = f2_as_vfinal_method();
assert(m->is_method(), "");
return m;
} else {
int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
if (cpool->tag_at(holder_index).is_klass()) {
Klass* klass = cpool->resolved_klass_at(holder_index);
return klass->method_at_vtable(f2_as_index());
}
}
break;
default:
break;
}
}
return NULL;
}
oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
if (!has_appendix())
return NULL;
const int ref_index = f2_as_index();
objArrayOop resolved_references = cpool->resolved_references();
return resolved_references->obj_at(ref_index);
}
#if INCLUDE_JVMTI
void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
if (log_is_enabled(Info, redefine, class, update)) {
ResourceMark rm;
if (!(*trace_name_printed)) {
log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
*trace_name_printed = true;
}
log_debug(redefine, class, update, constantpool)
("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string());
}
}
// RedefineClasses() API support:
// If this ConstantPoolCacheEntry refers to old_method then update it
// to refer to new_method.
void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
Method* new_method, bool * trace_name_printed) {
if (is_vfinal()) {
// virtual and final so _f2 contains method ptr instead of vtable index
if (f2_as_vfinal_method() == old_method) {
// match old_method so need an update
// NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
_f2 = (intptr_t)new_method;
log_adjust("vfinal", old_method, new_method, trace_name_printed);
}
return;
}
assert (_f1 != NULL, "should not call with uninteresting entry");
if (!(_f1->is_method())) {
// _f1 is a Klass* for an interface, _f2 is the method
if (f2_as_interface_method() == old_method) {
_f2 = (intptr_t)new_method;
log_adjust("interface", old_method, new_method, trace_name_printed);
}
} else if (_f1 == old_method) {
_f1 = new_method;
log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed);
}
}
// a constant pool cache entry should never contain old or obsolete methods
bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
Method* m = get_interesting_method_entry();
// return false if m refers to a non-deleted old or obsolete method
if (m != NULL) {
assert(m->is_valid() && m->is_method(), "m is a valid method");
return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete
} else {
return true;
}
}
Method* ConstantPoolCacheEntry::get_interesting_method_entry() {
if (!is_method_entry()) {
// not a method entry so not interesting by default
return NULL;
}
Method* m = NULL;
if (is_vfinal()) {
// virtual and final so _f2 contains method ptr instead of vtable index
m = f2_as_vfinal_method();
} else if (is_f1_null()) {
// NULL _f1 means this is a virtual entry so also not interesting
return NULL;
} else {
if (!(_f1->is_method())) {
// _f1 is a Klass* for an interface
m = f2_as_interface_method();
} else {
m = f1_as_method();
}
}
assert(m != NULL && m->is_method(), "sanity check");
if (m == NULL || !m->is_method()) {
return NULL;
}
return m;
}
#endif // INCLUDE_JVMTI
void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
// print separator
if (index == 0) st->print_cr(" -------------");
// print entry
st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
constant_pool_index());
st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
st->print_cr(" -------------");
}
void ConstantPoolCacheEntry::verify(outputStream* st) const {
// not implemented yet
}
// Implementation of ConstantPoolCache
ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
const intStack& index_map,
const intStack& invokedynamic_index_map,
const intStack& invokedynamic_map, TRAPS) {
const int length = index_map.length() + invokedynamic_index_map.length();
int size = ConstantPoolCache::size(length);
return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
}
void ConstantPoolCache::initialize(const intArray& inverse_index_map,
const intArray& invokedynamic_inverse_index_map,
const intArray& invokedynamic_references_map) {
for (int i = 0; i < inverse_index_map.length(); i++) {
ConstantPoolCacheEntry* e = entry_at(i);
int original_index = inverse_index_map.at(i);
e->initialize_entry(original_index);
assert(entry_at(i) == e, "sanity");
}
// Append invokedynamic entries at the end
int invokedynamic_offset = inverse_index_map.length();
for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
int offset = i + invokedynamic_offset;
ConstantPoolCacheEntry* e = entry_at(offset);
int original_index = invokedynamic_inverse_index_map.at(i);
e->initialize_entry(original_index);
assert(entry_at(offset) == e, "sanity");
}
for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
const int cpci = invokedynamic_references_map.at(ref);
if (cpci >= 0) {
entry_at(cpci)->initialize_resolved_reference_index(ref);
}
}
}
void ConstantPoolCache::verify_just_initialized() {
DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
}
void ConstantPoolCache::remove_unshareable_info() {
walk_entries_for_initialization(/*check_only = */ false);
}
void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
Arguments::assert_is_dumping_archive();
// When dumping the archive, we want to clean up the ConstantPoolCache
// to remove any effect of linking due to the execution of Java code --
// each ConstantPoolCacheEntry will have the same contents as if
// ConstantPoolCache::initialize has just returned:
//
// - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
// - We keep the "f2" field for entries used by invokedynamic and invokehandle
// - All other bits in the entries are cleared to zero.
ResourceMark rm;
InstanceKlass* ik = constant_pool()->pool_holder();
bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
memset(f2_used, 0, sizeof(bool) * length());
Thread* THREAD = Thread::current();
// Find all the slots that we need to preserve f2
for (int i = 0; i < ik->methods()->length(); i++) {
Method* m = ik->methods()->at(i);
RawBytecodeStream bcs(methodHandle(THREAD, m));
while (!bcs.is_last_bytecode()) {
Bytecodes::Code opcode = bcs.raw_next();
switch (opcode) {
case Bytecodes::_invokedynamic: {
int index = Bytes::get_native_u4(bcs.bcp() + 1);
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