JDK14/Java14源码在线阅读
/*
* Copyright (c) 1997, 2019, 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 "jvm.h"
#include "classfile/defaultMethods.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/resolutionErrors.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmSymbols.hpp"
#include "compiler/compilationPolicy.hpp"
#include "compiler/compileBroker.hpp"
#include "gc/shared/collectedHeap.inline.hpp"
#include "interpreter/bootstrapInfo.hpp"
#include "interpreter/bytecode.hpp"
#include "interpreter/interpreterRuntime.hpp"
#include "interpreter/linkResolver.hpp"
#include "logging/log.hpp"
#include "logging/logStream.hpp"
#include "memory/resourceArea.hpp"
#include "oops/constantPool.hpp"
#include "oops/cpCache.inline.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/method.hpp"
#include "oops/objArrayKlass.hpp"
#include "oops/objArrayOop.hpp"
#include "oops/oop.inline.hpp"
#include "prims/methodHandles.hpp"
#include "prims/nativeLookup.hpp"
#include "runtime/fieldDescriptor.inline.hpp"
#include "runtime/frame.inline.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/reflection.hpp"
#include "runtime/safepointVerifiers.hpp"
#include "runtime/signature.hpp"
#include "runtime/thread.inline.hpp"
#include "runtime/vmThread.hpp"
//------------------------------------------------------------------------------------------------------------------------
// Implementation of CallInfo
void CallInfo::set_static(Klass* resolved_klass, const methodHandle& resolved_method, TRAPS) {
int vtable_index = Method::nonvirtual_vtable_index;
set_common(resolved_klass, resolved_klass, resolved_method, resolved_method, CallInfo::direct_call, vtable_index, CHECK);
}
void CallInfo::set_interface(Klass* resolved_klass,
Klass* selected_klass,
const methodHandle& resolved_method,
const methodHandle& selected_method,
int itable_index, TRAPS) {
// This is only called for interface methods. If the resolved_method
// comes from java/lang/Object, it can be the subject of a virtual call, so
// we should pick the vtable index from the resolved method.
// In that case, the caller must call set_virtual instead of set_interface.
assert(resolved_method->method_holder()->is_interface(), "");
assert(itable_index == resolved_method()->itable_index(), "");
set_common(resolved_klass, selected_klass, resolved_method, selected_method, CallInfo::itable_call, itable_index, CHECK);
}
void CallInfo::set_virtual(Klass* resolved_klass,
Klass* selected_klass,
const methodHandle& resolved_method,
const methodHandle& selected_method,
int vtable_index, TRAPS) {
assert(vtable_index >= 0 || vtable_index == Method::nonvirtual_vtable_index, "valid index");
assert(vtable_index < 0 || !resolved_method->has_vtable_index() || vtable_index == resolved_method->vtable_index(), "");
CallKind kind = (vtable_index >= 0 && !resolved_method->can_be_statically_bound() ? CallInfo::vtable_call : CallInfo::direct_call);
set_common(resolved_klass, selected_klass, resolved_method, selected_method, kind, vtable_index, CHECK);
assert(!resolved_method->is_compiled_lambda_form(), "these must be handled via an invokehandle call");
}
void CallInfo::set_handle(const methodHandle& resolved_method,
Handle resolved_appendix, TRAPS) {
set_handle(SystemDictionary::MethodHandle_klass(), resolved_method, resolved_appendix, CHECK);
}
void CallInfo::set_handle(Klass* resolved_klass,
const methodHandle& resolved_method,
Handle resolved_appendix, TRAPS) {
guarantee(resolved_method.not_null(), "resolved method is null");
assert(resolved_method->intrinsic_id() == vmIntrinsics::_invokeBasic ||
resolved_method->is_compiled_lambda_form(),
"linkMethod must return one of these");
int vtable_index = Method::nonvirtual_vtable_index;
assert(!resolved_method->has_vtable_index(), "");
set_common(resolved_klass, resolved_klass, resolved_method, resolved_method, CallInfo::direct_call, vtable_index, CHECK);
_resolved_appendix = resolved_appendix;
}
void CallInfo::set_common(Klass* resolved_klass,
Klass* selected_klass,
const methodHandle& resolved_method,
const methodHandle& selected_method,
CallKind kind,
int index,
TRAPS) {
assert(resolved_method->signature() == selected_method->signature(), "signatures must correspond");
_resolved_klass = resolved_klass;
_selected_klass = selected_klass;
_resolved_method = resolved_method;
_selected_method = selected_method;
_call_kind = kind;
_call_index = index;
_resolved_appendix = Handle();
DEBUG_ONLY(verify()); // verify before making side effects
CompilationPolicy::compile_if_required(selected_method, THREAD);
}
// utility query for unreflecting a method
CallInfo::CallInfo(Method* resolved_method, Klass* resolved_klass, TRAPS) {
Klass* resolved_method_holder = resolved_method->method_holder();
if (resolved_klass == NULL) { // 2nd argument defaults to holder of 1st
resolved_klass = resolved_method_holder;
}
_resolved_klass = resolved_klass;
_selected_klass = resolved_klass;
_resolved_method = methodHandle(THREAD, resolved_method);
_selected_method = methodHandle(THREAD, resolved_method);
// classify:
CallKind kind = CallInfo::unknown_kind;
int index = resolved_method->vtable_index();
if (resolved_method->can_be_statically_bound()) {
kind = CallInfo::direct_call;
} else if (!resolved_method_holder->is_interface()) {
// Could be an Object method inherited into an interface, but still a vtable call.
kind = CallInfo::vtable_call;
} else if (!resolved_klass->is_interface()) {
// A default or miranda method. Compute the vtable index.
index = LinkResolver::vtable_index_of_interface_method(resolved_klass,
_resolved_method);
assert(index >= 0 , "we should have valid vtable index at this point");
kind = CallInfo::vtable_call;
} else if (resolved_method->has_vtable_index()) {
// Can occur if an interface redeclares a method of Object.
#ifdef ASSERT
// Ensure that this is really the case.
Klass* object_klass = SystemDictionary::Object_klass();
Method * object_resolved_method = object_klass->vtable().method_at(index);
assert(object_resolved_method->name() == resolved_method->name(),
"Object and interface method names should match at vtable index %d, %s != %s",
index, object_resolved_method->name()->as_C_string(), resolved_method->name()->as_C_string());
assert(object_resolved_method->signature() == resolved_method->signature(),
"Object and interface method signatures should match at vtable index %d, %s != %s",
index, object_resolved_method->signature()->as_C_string(), resolved_method->signature()->as_C_string());
#endif // ASSERT
kind = CallInfo::vtable_call;
} else {
// A regular interface call.
kind = CallInfo::itable_call;
index = resolved_method->itable_index();
}
assert(index == Method::nonvirtual_vtable_index || index >= 0, "bad index %d", index);
_call_kind = kind;
_call_index = index;
_resolved_appendix = Handle();
// Find or create a ResolvedMethod instance for this Method*
set_resolved_method_name(CHECK);
DEBUG_ONLY(verify());
}
void CallInfo::set_resolved_method_name(TRAPS) {
assert(_resolved_method() != NULL, "Should already have a Method*");
oop rmethod_name = java_lang_invoke_ResolvedMethodName::find_resolved_method(_resolved_method, CHECK);
_resolved_method_name = Handle(THREAD, rmethod_name);
}
#ifdef ASSERT
void CallInfo::verify() {
switch (call_kind()) { // the meaning and allowed value of index depends on kind
case CallInfo::direct_call:
if (_call_index == Method::nonvirtual_vtable_index) break;
// else fall through to check vtable index:
case CallInfo::vtable_call:
assert(resolved_klass()->verify_vtable_index(_call_index), "");
break;
case CallInfo::itable_call:
assert(resolved_method()->method_holder()->verify_itable_index(_call_index), "");
break;
case CallInfo::unknown_kind:
assert(call_kind() != CallInfo::unknown_kind, "CallInfo must be set");
break;
default:
fatal("Unexpected call kind %d", call_kind());
}
}
#endif // ASSERT
#ifndef PRODUCT
void CallInfo::print() {
ResourceMark rm;
const char* kindstr;
switch (_call_kind) {
case direct_call: kindstr = "direct"; break;
case vtable_call: kindstr = "vtable"; break;
case itable_call: kindstr = "itable"; break;
default : kindstr = "unknown"; break;
}
tty->print_cr("Call %s@%d %s", kindstr, _call_index,
_resolved_method.is_null() ? "(none)" : _resolved_method->name_and_sig_as_C_string());
}
#endif
//------------------------------------------------------------------------------------------------------------------------
// Implementation of LinkInfo
LinkInfo::LinkInfo(const constantPoolHandle& pool, int index, const methodHandle& current_method, TRAPS) {
// resolve klass
_resolved_klass = pool->klass_ref_at(index, CHECK);
// Get name, signature, and static klass
_name = pool->name_ref_at(index);
_signature = pool->signature_ref_at(index);
_tag = pool->tag_ref_at(index);
_current_klass = pool->pool_holder();
_current_method = current_method;
// Coming from the constant pool always checks access
_check_access = true;
}
LinkInfo::LinkInfo(const constantPoolHandle& pool, int index, TRAPS) {
// resolve klass
_resolved_klass = pool->klass_ref_at(index, CHECK);
// Get name, signature, and static klass
_name = pool->name_ref_at(index);
_signature = pool->signature_ref_at(index);
_tag = pool->tag_ref_at(index);
_current_klass = pool->pool_holder();
_current_method = methodHandle();
// Coming from the constant pool always checks access
_check_access = true;
}
#ifndef PRODUCT
void LinkInfo::print() {
ResourceMark rm;
tty->print_cr("Link resolved_klass=%s name=%s signature=%s current_klass=%s check_access=%s",
_resolved_klass->name()->as_C_string(),
_name->as_C_string(),
_signature->as_C_string(),
_current_klass == NULL ? "(none)" : _current_klass->name()->as_C_string(),
_check_access ? "true" : "false");
}
#endif // PRODUCT
//------------------------------------------------------------------------------------------------------------------------
// Klass resolution
void LinkResolver::check_klass_accessability(Klass* ref_klass, Klass* sel_klass,
bool fold_type_to_class, TRAPS) {
Klass* base_klass = sel_klass;
if (fold_type_to_class) {
if (sel_klass->is_objArray_klass()) {
base_klass = ObjArrayKlass::cast(sel_klass)->bottom_klass();
}
// The element type could be a typeArray - we only need the access
// check if it is a reference to another class.
if (!base_klass->is_instance_klass()) {
return; // no relevant check to do
}
}
Reflection::VerifyClassAccessResults vca_result =
Reflection::verify_class_access(ref_klass, InstanceKlass::cast(base_klass), true);
if (vca_result != Reflection::ACCESS_OK) {
ResourceMark rm(THREAD);
char* msg = Reflection::verify_class_access_msg(ref_klass,
InstanceKlass::cast(base_klass),
vca_result);
bool same_module = (base_klass->module() == ref_klass->module());
if (msg == NULL) {
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_IllegalAccessError(),
"failed to access class %s from class %s (%s%s%s)",
base_klass->external_name(),
ref_klass->external_name(),
(same_module) ? base_klass->joint_in_module_of_loader(ref_klass) : base_klass->class_in_module_of_loader(),
(same_module) ? "" : "; ",
(same_module) ? "" : ref_klass->class_in_module_of_loader());
} else {
// Use module specific message returned by verify_class_access_msg().
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_IllegalAccessError(),
"%s", msg);
}
}
}
//------------------------------------------------------------------------------------------------------------------------
// Method resolution
//
// According to JVM spec. $5.4.3c & $5.4.3d
// Look up method in klasses, including static methods
// Then look up local default methods
Method* LinkResolver::lookup_method_in_klasses(const LinkInfo& link_info,
bool checkpolymorphism,
bool in_imethod_resolve) {
NoSafepointVerifier nsv; // Method* returned may not be reclaimed
Klass* klass = link_info.resolved_klass();
Symbol* name = link_info.name();
Symbol* signature = link_info.signature();
// Ignore overpasses so statics can be found during resolution
Method* result = klass->uncached_lookup_method(name, signature, Klass::skip_overpass);
if (klass->is_array_klass()) {
// Only consider klass and super klass for arrays
return result;
}
InstanceKlass* ik = InstanceKlass::cast(klass);
// JDK 8, JVMS 5.4.3.4: Interface method resolution should
// ignore static and non-public methods of java.lang.Object,
// like clone, finalize, registerNatives.
if (in_imethod_resolve &&
result != NULL &&
ik->is_interface() &&
(result->is_static() || !result->is_public()) &&
result->method_holder() == SystemDictionary::Object_klass()) {
result = NULL;
}
// Before considering default methods, check for an overpass in the
// current class if a method has not been found.
if (result == NULL) {
result = ik->find_method(name, signature);
}
if (result == NULL) {
Array<Method*>* default_methods = ik->default_methods();
if (default_methods != NULL) {
result = InstanceKlass::find_method(default_methods, name, signature);
}
}
if (checkpolymorphism && result != NULL) {
vmIntrinsics::ID iid = result->intrinsic_id();
if (MethodHandles::is_signature_polymorphic(iid)) {
// Do not link directly to these. The VM must produce a synthetic one using lookup_polymorphic_method.
return NULL;
}
}
return result;
}
// returns first instance method
// Looks up method in classes, then looks up local default methods
Method* LinkResolver::lookup_instance_method_in_klasses(Klass* klass,
Symbol* name,
Symbol* signature,
Klass::PrivateLookupMode private_mode, TRAPS) {
Method* result = klass->uncached_lookup_method(name, signature, Klass::find_overpass, private_mode);
while (result != NULL && result->is_static() && result->method_holder()->super() != NULL) {
Klass* super_klass = result->method_holder()->super();
result = super_klass->uncached_lookup_method(name, signature, Klass::find_overpass, private_mode);
}
if (klass->is_array_klass()) {
// Only consider klass and super klass for arrays
return result;
}
if (result == NULL) {
Array<Method*>* default_methods = InstanceKlass::cast(klass)->default_methods();
if (default_methods != NULL) {
result = InstanceKlass::find_method(default_methods, name, signature);
assert(result == NULL || !result->is_static(), "static defaults not allowed");
}
}
return result;
}
int LinkResolver::vtable_index_of_interface_method(Klass* klass,
const methodHandle& resolved_method) {
int vtable_index = Method::invalid_vtable_index;
Symbol* name = resolved_method->name();
Symbol* signature = resolved_method->signature();
InstanceKlass* ik = InstanceKlass::cast(klass);
// First check in default method array
if (!resolved_method->is_abstract() && ik->default_methods() != NULL) {
int index = InstanceKlass::find_method_index(ik->default_methods(),
name, signature, Klass::find_overpass,
Klass::find_static, Klass::find_private);
if (index >= 0 ) {
vtable_index = ik->default_vtable_indices()->at(index);
}
}
if (vtable_index == Method::invalid_vtable_index) {
// get vtable_index for miranda methods
klassVtable vt = ik->vtable();
vtable_index = vt.index_of_miranda(name, signature);
}
return vtable_index;
}
Method* LinkResolver::lookup_method_in_interfaces(const LinkInfo& cp_info) {
InstanceKlass *ik = InstanceKlass::cast(cp_info.resolved_klass());
// Specify 'true' in order to skip default methods when searching the
// interfaces. Function lookup_method_in_klasses() already looked for
// the method in the default methods table.
return ik->lookup_method_in_all_interfaces(cp_info.name(), cp_info.signature(), Klass::skip_defaults);
}
Method* LinkResolver::lookup_polymorphic_method(const LinkInfo& link_info,
Handle *appendix_result_or_null,
TRAPS) {
Klass* klass = link_info.resolved_klass();
Symbol* name = link_info.name();
Symbol* full_signature = link_info.signature();
vmIntrinsics::ID iid = MethodHandles::signature_polymorphic_name_id(name);
if (TraceMethodHandles) {
ResourceMark rm(THREAD);
tty->print_cr("lookup_polymorphic_method iid=%s %s.%s%s",
vmIntrinsics::name_at(iid), klass->external_name(),
name->as_C_string(), full_signature->as_C_string());
}
if ((klass == SystemDictionary::MethodHandle_klass() ||
klass == SystemDictionary::VarHandle_klass()) &&
iid != vmIntrinsics::_none) {
if (MethodHandles::is_signature_polymorphic_intrinsic(iid)) {
// Most of these do not need an up-call to Java to resolve, so can be done anywhere.
// Do not erase last argument type (MemberName) if it is a static linkTo method.
bool keep_last_arg = MethodHandles::is_signature_polymorphic_static(iid);
TempNewSymbol basic_signature =
MethodHandles::lookup_basic_type_signature(full_signature, keep_last_arg, CHECK_NULL);
if (TraceMethodHandles) {
ResourceMark rm(THREAD);
tty->print_cr("lookup_polymorphic_method %s %s => basic %s",
name->as_C_string(),
full_signature->as_C_string(),
basic_signature->as_C_string());
}
Method* result = SystemDictionary::find_method_handle_intrinsic(iid,
basic_signature,
CHECK_NULL);
if (result != NULL) {
assert(result->is_method_handle_intrinsic(), "MH.invokeBasic or MH.linkTo* intrinsic");
assert(result->intrinsic_id() != vmIntrinsics::_invokeGeneric, "wrong place to find this");
assert(basic_signature == result->signature(), "predict the result signature");
if (TraceMethodHandles) {
ttyLocker ttyl;
tty->print("lookup_polymorphic_method => intrinsic ");
result->print_on(tty);
}
}
return result;
} else if (iid == vmIntrinsics::_invokeGeneric
&& THREAD->can_call_java()
&& appendix_result_or_null != NULL) {
// This is a method with type-checking semantics.
// We will ask Java code to spin an adapter method for it.
if (!MethodHandles::enabled()) {
// Make sure the Java part of the runtime has been booted up.
Klass* natives = SystemDictionary::MethodHandleNatives_klass();
if (natives == NULL || InstanceKlass::cast(natives)->is_not_initialized()) {
SystemDictionary::resolve_or_fail(vmSymbols::java_lang_invoke_MethodHandleNatives(),
Handle(),
Handle(),
true,
CHECK_NULL);
}
}
Handle appendix;
Handle method_type;
Method* result = SystemDictionary::find_method_handle_invoker(
klass,
name,
full_signature,
link_info.current_klass(),
&appendix,
CHECK_NULL);
if (TraceMethodHandles) {
ttyLocker ttyl;
tty->print("lookup_polymorphic_method => (via Java) ");
result->print_on(tty);
tty->print(" lookup_polymorphic_method => appendix = ");
if (appendix.is_null()) tty->print_cr("(none)");
else appendix->print_on(tty);
}
if (result != NULL) {
#ifdef ASSERT
ResourceMark rm(THREAD);
TempNewSymbol basic_signature =
MethodHandles::lookup_basic_type_signature(full_signature, CHECK_NULL);
int actual_size_of_params = result->size_of_parameters();
int expected_size_of_params = ArgumentSizeComputer(basic_signature).size();
// +1 for MethodHandle.this, +1 for trailing MethodType
if (!MethodHandles::is_signature_polymorphic_static(iid)) expected_size_of_params += 1;
if (appendix.not_null()) expected_size_of_params += 1;
if (actual_size_of_params != expected_size_of_params) {
tty->print_cr("*** basic_signature=%s", basic_signature->as_C_string());
tty->print_cr("*** result for %s: ", vmIntrinsics::name_at(iid));
result->print();
}
assert(actual_size_of_params == expected_size_of_params,
"%d != %d", actual_size_of_params, expected_size_of_params);
#endif //ASSERT
assert(appendix_result_or_null != NULL, "");
(*appendix_result_or_null) = appendix;
}
return result;
}
}
return NULL;
}
void LinkResolver::check_method_accessability(Klass* ref_klass,
Klass* resolved_klass,
Klass* sel_klass,
const methodHandle& sel_method,
TRAPS) {
AccessFlags flags = sel_method->access_flags();
// Special case: arrays always override "clone". JVMS 2.15.
// If the resolved klass is an array class, and the declaring class
// is java.lang.Object and the method is "clone", set the flags
// to public.
//
// We'll check for the method name first, as that's most likely
// to be false (so we'll short-circuit out of these tests).
if (sel_method->name() == vmSymbols::clone_name() &&
sel_klass == SystemDictionary::Object_klass() &&
resolved_klass->is_array_klass()) {
// We need to change "protected" to "public".
assert(flags.is_protected(), "clone not protected?");
jint new_flags = flags.as_int();
new_flags = new_flags & (~JVM_ACC_PROTECTED);
new_flags = new_flags | JVM_ACC_PUBLIC;
flags.set_flags(new_flags);
}
// assert(extra_arg_result_or_null != NULL, "must be able to return extra argument");
bool can_access = Reflection::verify_member_access(ref_klass,
resolved_klass,
sel_klass,
flags,
true, false, CHECK);
// Any existing exceptions that may have been thrown, for example LinkageErrors
// from nest-host resolution, have been allowed to propagate.
if (!can_access) {
ResourceMark rm(THREAD);
bool same_module = (sel_klass->module() == ref_klass->module());
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_IllegalAccessError(),
"class %s tried to access %s%s%smethod '%s' (%s%s%s)",
ref_klass->external_name(),
sel_method->is_abstract() ? "abstract " : "",
sel_method->is_protected() ? "protected " : "",
sel_method->is_private() ? "private " : "",
sel_method->external_name(),
(same_module) ? ref_klass->joint_in_module_of_loader(sel_klass) : ref_klass->class_in_module_of_loader(),
(same_module) ? "" : "; ",
(same_module) ? "" : sel_klass->class_in_module_of_loader()
);
return;
}
}
Method* LinkResolver::resolve_method_statically(Bytecodes::Code code,
const constantPoolHandle& pool, int index, TRAPS) {
// This method is used only
// (1) in C2 from InlineTree::ok_to_inline (via ciMethod::check_call),
// and
// (2) in Bytecode_invoke::static_target
// It appears to fail when applied to an invokeinterface call site.
// FIXME: Remove this method and ciMethod::check_call; refactor to use the other LinkResolver entry points.
// resolve klass
if (code == Bytecodes::_invokedynamic) {
Klass* resolved_klass = SystemDictionary::MethodHandle_klass();
Symbol* method_name = vmSymbols::invoke_name();
Symbol* method_signature = pool->signature_ref_at(index);
Klass* current_klass = pool->pool_holder();
LinkInfo link_info(resolved_klass, method_name, method_signature, current_klass);
return resolve_method(link_info, code, THREAD);
}
LinkInfo link_info(pool, index, methodHandle(), CHECK_NULL);
Klass* resolved_klass = link_info.resolved_klass();
if (pool->has_preresolution()
|| (resolved_klass == SystemDictionary::MethodHandle_klass() &&
MethodHandles::is_signature_polymorphic_name(resolved_klass, link_info.name()))) {
Method* result = ConstantPool::method_at_if_loaded(pool, index);
if (result != NULL) {
return result;
}
}
if (code == Bytecodes::_invokeinterface) {
return resolve_interface_method(link_info, code, THREAD);
} else if (code == Bytecodes::_invokevirtual) {
return resolve_method(link_info, code, THREAD);
} else if (!resolved_klass->is_interface()) {
return resolve_method(link_info, code, THREAD);
} else {
return resolve_interface_method(link_info, code, THREAD);
}
}
// Check and print a loader constraint violation message for method or interface method
void LinkResolver::check_method_loader_constraints(const LinkInfo& link_info,
const methodHandle& resolved_method,
const char* method_type, TRAPS) {
Handle current_loader(THREAD, link_info.current_klass()->class_loader());
Handle resolved_loader(THREAD, resolved_method->method_holder()->class_loader());
ResourceMark rm(THREAD);
Symbol* failed_type_symbol =
SystemDictionary::check_signature_loaders(link_info.signature(), current_loader,
resolved_loader, true, CHECK);
if (failed_type_symbol != NULL) {
Klass* current_class = link_info.current_klass();
ClassLoaderData* current_loader_data = current_class->class_loader_data();
assert(current_loader_data != NULL, "current class has no class loader data");
Klass* resolved_method_class = resolved_method->method_holder();
ClassLoaderData* target_loader_data = resolved_method_class->class_loader_data();
assert(target_loader_data != NULL, "resolved method's class has no class loader data");
stringStream ss;
ss.print("loader constraint violation: when resolving %s '", method_type);
Method::print_external_name(&ss, link_info.resolved_klass(), link_info.name(), link_info.signature());
ss.print("' the class loader %s of the current class, %s,"
" and the class loader %s for the method's defining class, %s, have"
" different Class objects for the type %s used in the signature (%s; %s)",
current_loader_data->loader_name_and_id(),
current_class->name()->as_C_string(),
target_loader_data->loader_name_and_id(),
resolved_method_class->name()->as_C_string(),
failed_type_symbol->as_C_string(),
current_class->class_in_module_of_loader(false, true),
resolved_method_class->class_in_module_of_loader(false, true));
THROW_MSG(vmSymbols::java_lang_LinkageError(), ss.as_string());
}
}
void LinkResolver::check_field_loader_constraints(Symbol* field, Symbol* sig,
Klass* current_klass,
Klass* sel_klass, TRAPS) {
Handle ref_loader(THREAD, current_klass->class_loader());
Handle sel_loader(THREAD, sel_klass->class_loader());
ResourceMark rm(THREAD); // needed for check_signature_loaders
Symbol* failed_type_symbol =
SystemDictionary::check_signature_loaders(sig,
ref_loader, sel_loader,
false,
CHECK);
if (failed_type_symbol != NULL) {
stringStream ss;
const char* failed_type_name = failed_type_symbol->as_klass_external_name();
ss.print("loader constraint violation: when resolving field \"%s\" of type %s, "
"the class loader %s of the current class, %s, "
"and the class loader %s for the field's defining %s, %s, "
"have different Class objects for type %s (%s; %s)",
field->as_C_string(),
failed_type_name,
current_klass->class_loader_data()->loader_name_and_id(),
current_klass->external_name(),
sel_klass->class_loader_data()->loader_name_and_id(),
sel_klass->external_kind(),
sel_klass->external_name(),
failed_type_name,
current_klass->class_in_module_of_loader(false, true),
sel_klass->class_in_module_of_loader(false, true));
THROW_MSG(vmSymbols::java_lang_LinkageError(), ss.as_string());
}
}
Method* LinkResolver::resolve_method(const LinkInfo& link_info,
Bytecodes::Code code, TRAPS) {
Handle nested_exception;
Klass* resolved_klass = link_info.resolved_klass();
// 1. For invokevirtual, cannot call an interface method
if (code == Bytecodes::_invokevirtual && resolved_klass->is_interface()) {
ResourceMark rm(THREAD);
char buf[200];
jio_snprintf(buf, sizeof(buf), "Found interface %s, but class was expected",
resolved_klass->external_name());
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
}
// 2. check constant pool tag for called method - must be JVM_CONSTANT_Methodref
if (!link_info.tag().is_invalid() && !link_info.tag().is_method()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Method '");
Method::print_external_name(&ss, link_info.resolved_klass(), link_info.name(), link_info.signature());
ss.print("' must be Methodref constant");
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
// 3. lookup method in resolved klass and its super klasses
methodHandle resolved_method(THREAD, lookup_method_in_klasses(link_info, true, false));
// 4. lookup method in all the interfaces implemented by the resolved klass
if (resolved_method.is_null() && !resolved_klass->is_array_klass()) { // not found in the class hierarchy
resolved_method = methodHandle(THREAD, lookup_method_in_interfaces(link_info));
if (resolved_method.is_null()) {
// JSR 292: see if this is an implicitly generated method MethodHandle.linkToVirtual(*...), etc
Method* method = lookup_polymorphic_method(link_info, (Handle*)NULL, THREAD);
resolved_method = methodHandle(THREAD, method);
if (HAS_PENDING_EXCEPTION) {
nested_exception = Handle(THREAD, PENDING_EXCEPTION);
CLEAR_PENDING_EXCEPTION;
}
}
}
// 5. method lookup failed
if (resolved_method.is_null()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("'");
Method::print_external_name(&ss, resolved_klass, link_info.name(), link_info.signature());
ss.print("'");
THROW_MSG_CAUSE_(vmSymbols::java_lang_NoSuchMethodError(),
ss.as_string(), nested_exception, NULL);
}
// 6. access checks, access checking may be turned off when calling from within the VM.
Klass* current_klass = link_info.current_klass();
if (link_info.check_access()) {
assert(current_klass != NULL , "current_klass should not be null");
// check if method can be accessed by the referring class
check_method_accessability(current_klass,
resolved_klass,
resolved_method->method_holder(),
resolved_method,
CHECK_NULL);
// check loader constraints
check_method_loader_constraints(link_info, resolved_method, "method", CHECK_NULL);
}
return resolved_method();
}
static void trace_method_resolution(const char* prefix,
Klass* klass,
Klass* resolved_klass,
Method* method,
bool logitables,
int index = -1) {
#ifndef PRODUCT
ResourceMark rm;
Log(itables) logi;
LogStream lsi(logi.trace());
Log(vtables) logv;
LogStream lsv(logv.trace());
outputStream* st;
if (logitables) {
st = &lsi;
} else {
st = &lsv;
}
st->print("%s%s, compile-time-class:%s, method:%s, method_holder:%s, access_flags: ",
prefix,
(klass == NULL ? "<NULL>" : klass->internal_name()),
(resolved_klass == NULL ? "<NULL>" : resolved_klass->internal_name()),
Method::name_and_sig_as_C_string(resolved_klass,
method->name(),
method->signature()),
method->method_holder()->internal_name());
method->print_linkage_flags(st);
if (index != -1) {
st->print("vtable_index:%d", index);
}
st->cr();
#endif // PRODUCT
}
// Do linktime resolution of a method in the interface within the context of the specied bytecode.
Method* LinkResolver::resolve_interface_method(const LinkInfo& link_info, Bytecodes::Code code, TRAPS) {
Klass* resolved_klass = link_info.resolved_klass();
// check if klass is interface
if (!resolved_klass->is_interface()) {
ResourceMark rm(THREAD);
char buf[200];
jio_snprintf(buf, sizeof(buf), "Found class %s, but interface was expected", resolved_klass->external_name());
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
}
// check constant pool tag for called method - must be JVM_CONSTANT_InterfaceMethodref
if (!link_info.tag().is_invalid() && !link_info.tag().is_interface_method()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Method '");
Method::print_external_name(&ss, link_info.resolved_klass(), link_info.name(), link_info.signature());
ss.print("' must be InterfaceMethodref constant");
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
// lookup method in this interface or its super, java.lang.Object
// JDK8: also look for static methods
methodHandle resolved_method(THREAD, lookup_method_in_klasses(link_info, false, true));
if (resolved_method.is_null() && !resolved_klass->is_array_klass()) {
// lookup method in all the super-interfaces
resolved_method = methodHandle(THREAD, lookup_method_in_interfaces(link_info));
}
if (resolved_method.is_null()) {
// no method found
ResourceMark rm(THREAD);
stringStream ss;
ss.print("'");
Method::print_external_name(&ss, resolved_klass, link_info.name(), link_info.signature());
ss.print("'");
THROW_MSG_NULL(vmSymbols::java_lang_NoSuchMethodError(), ss.as_string());
}
if (link_info.check_access()) {
// JDK8 adds non-public interface methods, and accessability check requirement
Klass* current_klass = link_info.current_klass();
assert(current_klass != NULL , "current_klass should not be null");
// check if method can be accessed by the referring class
check_method_accessability(current_klass,
resolved_klass,
resolved_method->method_holder(),
resolved_method,
CHECK_NULL);
check_method_loader_constraints(link_info, resolved_method, "interface method", CHECK_NULL);
}
if (code != Bytecodes::_invokestatic && resolved_method->is_static()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Expected instance not static method '");
Method::print_external_name(&ss, resolved_klass,
resolved_method->name(), resolved_method->signature());
ss.print("'");
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
if (log_develop_is_enabled(Trace, itables)) {
char buf[200];
jio_snprintf(buf, sizeof(buf), "%s resolved interface method: caller-class:",
Bytecodes::name(code));
trace_method_resolution(buf, link_info.current_klass(), resolved_klass, resolved_method(), true);
}
return resolved_method();
}
//------------------------------------------------------------------------------------------------------------------------
// Field resolution
void LinkResolver::check_field_accessability(Klass* ref_klass,
Klass* resolved_klass,
Klass* sel_klass,
const fieldDescriptor& fd,
TRAPS) {
bool can_access = Reflection::verify_member_access(ref_klass,
resolved_klass,
sel_klass,
fd.access_flags(),
true, false, CHECK);
// Any existing exceptions that may have been thrown, for example LinkageErrors
// from nest-host resolution, have been allowed to propagate.
if (!can_access) {
bool same_module = (sel_klass->module() == ref_klass->module());
ResourceMark rm(THREAD);
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_IllegalAccessError(),
"class %s tried to access %s%sfield %s.%s (%s%s%s)",
ref_klass->external_name(),
fd.is_protected() ? "protected " : "",
fd.is_private() ? "private " : "",
sel_klass->external_name(),
fd.name()->as_C_string(),
(same_module) ? ref_klass->joint_in_module_of_loader(sel_klass) : ref_klass->class_in_module_of_loader(),
(same_module) ? "" : "; ",
(same_module) ? "" : sel_klass->class_in_module_of_loader()
);
return;
}
}
void LinkResolver::resolve_field_access(fieldDescriptor& fd, const constantPoolHandle& pool, int index, const methodHandle& method, Bytecodes::Code byte, TRAPS) {
LinkInfo link_info(pool, index, method, CHECK);
resolve_field(fd, link_info, byte, true, CHECK);
}
void LinkResolver::resolve_field(fieldDescriptor& fd,
const LinkInfo& link_info,
Bytecodes::Code byte, bool initialize_class,
TRAPS) {
assert(byte == Bytecodes::_getstatic || byte == Bytecodes::_putstatic ||
byte == Bytecodes::_getfield || byte == Bytecodes::_putfield ||
byte == Bytecodes::_nofast_getfield || byte == Bytecodes::_nofast_putfield ||
(byte == Bytecodes::_nop && !link_info.check_access()), "bad field access bytecode");
bool is_static = (byte == Bytecodes::_getstatic || byte == Bytecodes::_putstatic);
bool is_put = (byte == Bytecodes::_putfield || byte == Bytecodes::_putstatic || byte == Bytecodes::_nofast_putfield);
// Check if there's a resolved klass containing the field
Klass* resolved_klass = link_info.resolved_klass();
Symbol* field = link_info.name();
Symbol* sig = link_info.signature();
if (resolved_klass == NULL) {
ResourceMark rm(THREAD);
THROW_MSG(vmSymbols::java_lang_NoSuchFieldError(), field->as_C_string());
}
// Resolve instance field
Klass* sel_klass = resolved_klass->find_field(field, sig, &fd);
// check if field exists; i.e., if a klass containing the field def has been selected
if (sel_klass == NULL) {
ResourceMark rm(THREAD);
THROW_MSG(vmSymbols::java_lang_NoSuchFieldError(), field->as_C_string());
}
// Access checking may be turned off when calling from within the VM.
Klass* current_klass = link_info.current_klass();
if (link_info.check_access()) {
// check access
check_field_accessability(current_klass, resolved_klass, sel_klass, fd, CHECK);
// check for errors
if (is_static != fd.is_static()) {
ResourceMark rm(THREAD);
char msg[200];
jio_snprintf(msg, sizeof(msg), "Expected %s field %s.%s", is_static ? "static" : "non-static", resolved_klass->external_name(), fd.name()->as_C_string());
THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), msg);
}
// A final field can be modified only
// (1) by methods declared in the class declaring the field and
// (2) by the <clinit> method (in case of a static field)
// or by the <init> method (in case of an instance field).
if (is_put && fd.access_flags().is_final()) {
ResourceMark rm(THREAD);
stringStream ss;
if (sel_klass != current_klass) {
ss.print("Update to %s final field %s.%s attempted from a different class (%s) than the field's declaring class",
is_static ? "static" : "non-static", resolved_klass->external_name(), fd.name()->as_C_string(),
current_klass->external_name());
THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), ss.as_string());
}
if (fd.constants()->pool_holder()->major_version() >= 53) {
Method* m = link_info.current_method();
assert(m != NULL, "information about the current method must be available for 'put' bytecodes");
bool is_initialized_static_final_update = (byte == Bytecodes::_putstatic &&
fd.is_static() &&
!m->is_static_initializer());
bool is_initialized_instance_final_update = ((byte == Bytecodes::_putfield || byte == Bytecodes::_nofast_putfield) &&
!fd.is_static() &&
!m->is_object_initializer());
if (is_initialized_static_final_update || is_initialized_instance_final_update) {
ss.print("Update to %s final field %s.%s attempted from a different method (%s) than the initializer method %s ",
is_static ? "static" : "non-static", resolved_klass->external_name(), fd.name()->as_C_string(),
m->name()->as_C_string(),
is_static ? "<clinit>" : "<init>");
THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), ss.as_string());
}
}
}
// initialize resolved_klass if necessary
// note 1: the klass which declared the field must be initialized (i.e, sel_klass)
// according to the newest JVM spec (5.5, p.170) - was bug (gri 7/28/99)
//
// note 2: we don't want to force initialization if we are just checking
// if the field access is legal; e.g., during compilation
if (is_static && initialize_class) {
sel_klass->initialize(CHECK);
}
}
if ((sel_klass != current_klass) && (current_klass != NULL)) {
check_field_loader_constraints(field, sig, current_klass, sel_klass, CHECK);
}
// return information. note that the klass is set to the actual klass containing the
// field, otherwise access of static fields in superclasses will not work.
}
//------------------------------------------------------------------------------------------------------------------------
// Invoke resolution
//
// Naming conventions:
//
// resolved_method the specified method (i.e., static receiver specified via constant pool index)
// sel_method the selected method (selected via run-time lookup; e.g., based on dynamic receiver class)
// resolved_klass the specified klass (i.e., specified via constant pool index)
// recv_klass the receiver klass
void LinkResolver::resolve_static_call(CallInfo& result,
const LinkInfo& link_info,
bool initialize_class, TRAPS) {
Method* resolved_method = linktime_resolve_static_method(link_info, CHECK);
// The resolved class can change as a result of this resolution.
Klass* resolved_klass = resolved_method->method_holder();
// Initialize klass (this should only happen if everything is ok)
if (initialize_class && resolved_klass->should_be_initialized()) {
resolved_klass->initialize(CHECK);
// Use updated LinkInfo to reresolve with resolved method holder
LinkInfo new_info(resolved_klass, link_info.name(), link_info.signature(),
link_info.current_klass(),
link_info.check_access() ? LinkInfo::needs_access_check : LinkInfo::skip_access_check);
resolved_method = linktime_resolve_static_method(new_info, CHECK);
}
// setup result
result.set_static(resolved_klass, methodHandle(THREAD, resolved_method), CHECK);
}
// throws linktime exceptions
Method* LinkResolver::linktime_resolve_static_method(const LinkInfo& link_info, TRAPS) {
Klass* resolved_klass = link_info.resolved_klass();
Method* resolved_method;
if (!resolved_klass->is_interface()) {
resolved_method = resolve_method(link_info, Bytecodes::_invokestatic, CHECK_NULL);
} else {
resolved_method = resolve_interface_method(link_info, Bytecodes::_invokestatic, CHECK_NULL);
}
assert(resolved_method->name() != vmSymbols::class_initializer_name(), "should have been checked in verifier");
// check if static
if (!resolved_method->is_static()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Expected static method '");
resolved_method->print_external_name(&ss);
ss.print("'");
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
return resolved_method;
}
void LinkResolver::resolve_special_call(CallInfo& result,
Handle recv,
const LinkInfo& link_info,
TRAPS) {
Method* resolved_method = linktime_resolve_special_method(link_info, CHECK);
runtime_resolve_special_method(result, link_info, methodHandle(THREAD, resolved_method), recv, CHECK);
}
// throws linktime exceptions
Method* LinkResolver::linktime_resolve_special_method(const LinkInfo& link_info, TRAPS) {
// Invokespecial is called for multiple special reasons:
// <init>
// local private method invocation, for classes and interfaces
// superclass.method, which can also resolve to a default method
// and the selected method is recalculated relative to the direct superclass
// superinterface.method, which explicitly does not check shadowing
Klass* resolved_klass = link_info.resolved_klass();
Method* resolved_method;
if (!resolved_klass->is_interface()) {
resolved_method = resolve_method(link_info, Bytecodes::_invokespecial, CHECK_NULL);
} else {
resolved_method = resolve_interface_method(link_info, Bytecodes::_invokespecial, CHECK_NULL);
}
// check if method name is <init>, that it is found in same klass as static type
if (resolved_method->name() == vmSymbols::object_initializer_name() &&
resolved_method->method_holder() != resolved_klass) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("%s: method '", resolved_klass->external_name());
resolved_method->signature()->print_as_signature_external_return_type(&ss);
ss.print(" %s(", resolved_method->name()->as_C_string());
resolved_method->signature()->print_as_signature_external_parameters(&ss);
ss.print(")' not found");
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_NoSuchMethodError(),
"%s", ss.as_string());
return NULL;
}
// ensure that invokespecial's interface method reference is in
// a direct superinterface, not an indirect superinterface
Klass* current_klass = link_info.current_klass();
if (current_klass != NULL && resolved_klass->is_interface()) {
InstanceKlass* ck = InstanceKlass::cast(current_klass);
InstanceKlass *klass_to_check = !ck->is_unsafe_anonymous() ?
ck :
ck->unsafe_anonymous_host();
// Disable verification for the dynamically-generated reflection bytecodes.
bool is_reflect = klass_to_check->is_subclass_of(
SystemDictionary::reflect_MagicAccessorImpl_klass());
if (!is_reflect &&
!klass_to_check->is_same_or_direct_interface(resolved_klass)) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Interface method reference: '");
resolved_method->print_external_name(&ss);
ss.print("', is in an indirect superinterface of %s",
current_klass->external_name());
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
}
// check if not static
if (resolved_method->is_static()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Expecting non-static method '");
resolved_method->print_external_name(&ss);
ss.print("'");
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
if (log_develop_is_enabled(Trace, itables)) {
trace_method_resolution("invokespecial resolved method: caller-class:",
current_klass, resolved_klass, resolved_method, true);
}
return resolved_method;
}
// throws runtime exceptions
void LinkResolver::runtime_resolve_special_method(CallInfo& result,
const LinkInfo& link_info,
const methodHandle& resolved_method,
Handle recv, TRAPS) {
Klass* resolved_klass = link_info.resolved_klass();
// resolved method is selected method unless we have an old-style lookup
// for a superclass method
// Invokespecial for a superinterface, resolved method is selected method,
// no checks for shadowing
methodHandle sel_method(THREAD, resolved_method());
if (link_info.check_access() &&
// check if the method is not <init>
resolved_method->name() != vmSymbols::object_initializer_name()) {
Klass* current_klass = link_info.current_klass();
// Check if the class of the resolved_klass is a superclass
// (not supertype in order to exclude interface classes) of the current class.
// This check is not performed for super.invoke for interface methods
// in super interfaces.
if (current_klass->is_subclass_of(resolved_klass) &&
current_klass != resolved_klass) {
// Lookup super method
Klass* super_klass = current_klass->super();
Method* instance_method = lookup_instance_method_in_klasses(super_klass,
resolved_method->name(),
resolved_method->signature(),
Klass::find_private, CHECK);
sel_method = methodHandle(THREAD, instance_method);
// check if found
if (sel_method.is_null()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("'");
resolved_method->print_external_name(&ss);
ss.print("'");
THROW_MSG(vmSymbols::java_lang_AbstractMethodError(), ss.as_string());
// check loader constraints if found a different method
} else if (sel_method() != resolved_method()) {
check_method_loader_constraints(link_info, sel_method, "method", CHECK);
}
}
// Check that the class of objectref (the receiver) is the current class or interface,
// or a subtype of the current class or interface (the sender), otherwise invokespecial
// throws IllegalAccessError.
// The verifier checks that the sender is a subtype of the class in the I/MR operand.
// The verifier also checks that the receiver is a subtype of the sender, if the sender is
// a class. If the sender is an interface, the check has to be performed at runtime.
InstanceKlass* sender = InstanceKlass::cast(current_klass);
sender = sender->is_unsafe_anonymous() ? sender->unsafe_anonymous_host() : sender;
if (sender->is_interface() && recv.not_null()) {
Klass* receiver_klass = recv->klass();
if (!receiver_klass->is_subtype_of(sender)) {
ResourceMark rm(THREAD);
char buf[500];
jio_snprintf(buf, sizeof(buf),
"Receiver class %s must be the current class or a subtype of interface %s",
receiver_klass->external_name(),
sender->external_name());
THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), buf);
}
}
}
// check if not static
if (sel_method->is_static()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Expecting non-static method '");
resolved_method->print_external_name(&ss);
ss.print("'");
THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
// check if abstract
if (sel_method->is_abstract()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("'");
Method::print_external_name(&ss, resolved_klass, sel_method->name(), sel_method->signature());
ss.print("'");
THROW_MSG(vmSymbols::java_lang_AbstractMethodError(), ss.as_string());
}
if (log_develop_is_enabled(Trace, itables)) {
trace_method_resolution("invokespecial selected method: resolved-class:",
resolved_klass, resolved_klass, sel_method(), true);
}
// setup result
result.set_static(resolved_klass, sel_method, CHECK);
}
void LinkResolver::resolve_virtual_call(CallInfo& result, Handle recv, Klass* receiver_klass,
const LinkInfo& link_info,
bool check_null_and_abstract, TRAPS) {
Method* resolved_method = linktime_resolve_virtual_method(link_info, CHECK);
runtime_resolve_virtual_method(result, methodHandle(THREAD, resolved_method),
link_info.resolved_klass(),
recv, receiver_klass,
check_null_and_abstract, CHECK);
}
// throws linktime exceptions
Method* LinkResolver::linktime_resolve_virtual_method(const LinkInfo& link_info,
TRAPS) {
// normal method resolution
Method* resolved_method = resolve_method(link_info, Bytecodes::_invokevirtual, CHECK_NULL);
assert(resolved_method->name() != vmSymbols::object_initializer_name(), "should have been checked in verifier");
assert(resolved_method->name() != vmSymbols::class_initializer_name (), "should have been checked in verifier");
// check if private interface method
Klass* resolved_klass = link_info.resolved_klass();
Klass* current_klass = link_info.current_klass();
// This is impossible, if resolve_klass is an interface, we've thrown icce in resolve_method
if (resolved_klass->is_interface() && resolved_method->is_private()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("private interface method requires invokespecial, not invokevirtual: method '");
resolved_method->print_external_name(&ss);
ss.print("', caller-class: %s",
(current_klass == NULL ? "<null>" : current_klass->internal_name()));
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
// check if not static
if (resolved_method->is_static()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("Expecting non-static method '");
resolved_method->print_external_name(&ss);
ss.print("'");
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
if (log_develop_is_enabled(Trace, vtables)) {
trace_method_resolution("invokevirtual resolved method: caller-class:",
current_klass, resolved_klass, resolved_method, false);
}
return resolved_method;
}
// throws runtime exceptions
void LinkResolver::runtime_resolve_virtual_method(CallInfo& result,
const methodHandle& resolved_method,
Klass* resolved_klass,
Handle recv,
Klass* recv_klass,
bool check_null_and_abstract,
TRAPS) {
// setup default return values
int vtable_index = Method::invalid_vtable_index;
methodHandle selected_method;
// runtime method resolution
if (check_null_and_abstract && recv.is_null()) { // check if receiver exists
THROW(vmSymbols::java_lang_NullPointerException());
}
// Virtual methods cannot be resolved before its klass has been linked, for otherwise the Method*'s
// has not been rewritten, and the vtable initialized. Make sure to do this after the nullcheck, since
// a missing receiver might result in a bogus lookup.
assert(resolved_method->method_holder()->is_linked(), "must be linked");
// do lookup based on receiver klass using the vtable index
if (resolved_method->method_holder()->is_interface()) { // default or miranda method
vtable_index = vtable_index_of_interface_method(resolved_klass, resolved_method);
assert(vtable_index >= 0 , "we should have valid vtable index at this point");
selected_method = methodHandle(THREAD, recv_klass->method_at_vtable(vtable_index));
} else {
// at this point we are sure that resolved_method is virtual and not
// a default or miranda method; therefore, it must have a valid vtable index.
assert(!resolved_method->has_itable_index(), "");
vtable_index = resolved_method->vtable_index();
// We could get a negative vtable_index of nonvirtual_vtable_index for private
// methods, or for final methods. Private methods never appear in the vtable
// and never override other methods. As an optimization, final methods are
// never put in the vtable, unless they override an existing method.
// So if we do get nonvirtual_vtable_index, it means the selected method is the
// resolved method, and it can never be changed by an override.
if (vtable_index == Method::nonvirtual_vtable_index) {
assert(resolved_method->can_be_statically_bound(), "cannot override this method");
selected_method = resolved_method;
} else {
selected_method = methodHandle(THREAD, recv_klass->method_at_vtable(vtable_index));
}
}
// check if method exists
if (selected_method.is_null()) {
throw_abstract_method_error(resolved_method, recv_klass, CHECK);
}
// check if abstract
if (check_null_and_abstract && selected_method->is_abstract()) {
// Pass arguments for generating a verbose error message.
throw_abstract_method_error(resolved_method, selected_method, recv_klass, CHECK);
}
if (log_develop_is_enabled(Trace, vtables)) {
trace_method_resolution("invokevirtual selected method: receiver-class:",
recv_klass, resolved_klass, selected_method(),
false, vtable_index);
}
// setup result
result.set_virtual(resolved_klass, recv_klass, resolved_method, selected_method, vtable_index, CHECK);
}
void LinkResolver::resolve_interface_call(CallInfo& result, Handle recv, Klass* recv_klass,
const LinkInfo& link_info,
bool check_null_and_abstract, TRAPS) {
// throws linktime exceptions
Method* resolved_method = linktime_resolve_interface_method(link_info, CHECK);
methodHandle mh(THREAD, resolved_method);
runtime_resolve_interface_method(result, mh, link_info.resolved_klass(),
recv, recv_klass, check_null_and_abstract, CHECK);
}
Method* LinkResolver::linktime_resolve_interface_method(const LinkInfo& link_info,
TRAPS) {
// normal interface method resolution
Method* resolved_method = resolve_interface_method(link_info, Bytecodes::_invokeinterface, CHECK_NULL);
assert(resolved_method->name() != vmSymbols::object_initializer_name(), "should have been checked in verifier");
assert(resolved_method->name() != vmSymbols::class_initializer_name (), "should have been checked in verifier");
return resolved_method;
}
// throws runtime exceptions
void LinkResolver::runtime_resolve_interface_method(CallInfo& result,
const methodHandle& resolved_method,
Klass* resolved_klass,
Handle recv,
Klass* recv_klass,
bool check_null_and_abstract, TRAPS) {
// check if receiver exists
if (check_null_and_abstract && recv.is_null()) {
THROW(vmSymbols::java_lang_NullPointerException());
}
// check if receiver klass implements the resolved interface
if (!recv_klass->is_subtype_of(resolved_klass)) {
ResourceMark rm(THREAD);
char buf[200];
jio_snprintf(buf, sizeof(buf), "Class %s does not implement the requested interface %s",
recv_klass->external_name(),
resolved_klass->external_name());
THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
}
methodHandle selected_method = resolved_method;
// resolve the method in the receiver class, unless it is private
if (!resolved_method()->is_private()) {
// do lookup based on receiver klass
// This search must match the linktime preparation search for itable initialization
// to correctly enforce loader constraints for interface method inheritance.
// Private methods are skipped as the resolved method was not private.
Method* method = lookup_instance_method_in_klasses(recv_klass,
resolved_method->name(),
resolved_method->signature(),
Klass::skip_private, CHECK);
selected_method = methodHandle(THREAD, method);
if (selected_method.is_null() && !check_null_and_abstract) {
// In theory this is a harmless placeholder value, but
// in practice leaving in null affects the nsk default method tests.
// This needs further study.
selected_method = resolved_method;
}
// check if method exists
if (selected_method.is_null()) {
// Pass arguments for generating a verbose error message.
throw_abstract_method_error(resolved_method, recv_klass, CHECK);
}
// check access
// Throw Illegal Access Error if selected_method is not public.
if (!selected_method->is_public()) {
ResourceMark rm(THREAD);
stringStream ss;
ss.print("'");
Method::print_external_name(&ss, recv_klass, selected_method->name(), selected_method->signature());
ss.print("'");
THROW_MSG(vmSymbols::java_lang_IllegalAccessError(), ss.as_string());
}
// check if abstract
if (check_null_and_abstract && selected_method->is_abstract()) {
throw_abstract_method_error(resolved_method, selected_method, recv_klass, CHECK);
}
}
if (log_develop_is_enabled(Trace, itables)) {
trace_method_resolution("invokeinterface selected method: receiver-class:",
recv_klass, resolved_klass, selected_method(), true);
}
// setup result
if (resolved_method->has_vtable_index()) {
int vtable_index = resolved_method->vtable_index();
log_develop_trace(itables)(" -- vtable index: %d", vtable_index);
assert(vtable_index == selected_method->vtable_index(), "sanity check");
result.set_virtual(resolved_klass, recv_klass, resolved_method, selected_method, vtable_index, CHECK);
} else if (resolved_method->has_itable_index()) {
int itable_index = resolved_method()->itable_index();
log_develop_trace(itables)(" -- itable index: %d", itable_index);
result.set_interface(resolved_klass, recv_klass, resolved_method, selected_method, itable_index, CHECK);
} else {
int index = resolved_method->vtable_index();
log_develop_trace(itables)(" -- non itable/vtable index: %d", index);
assert(index == Method::nonvirtual_vtable_index, "Oops hit another case!");
assert(resolved_method()->is_private() ||
(resolved_method()->is_final() && resolved_method->method_holder() == SystemDictionary::Object_klass()),
"Should only have non-virtual invokeinterface for private or final-Object methods!");
assert(resolved_method()->can_be_statically_bound(), "Should only have non-virtual invokeinterface for statically bound methods!");
// This sets up the nonvirtual form of "virtual" call (as needed for final and private methods)
result.set_virtual(resolved_klass, resolved_klass, resolved_method, resolved_method, index, CHECK);
}
}
Method* LinkResolver::linktime_resolve_interface_method_or_null(
const LinkInfo& link_info) {
EXCEPTION_MARK;
Method* method_result = linktime_resolve_interface_method(link_info, THREAD);
if (HAS_PENDING_EXCEPTION) {
CLEAR_PENDING_EXCEPTION;
return NULL;
} else {
return method_result;
}
}
Method* LinkResolver::linktime_resolve_virtual_method_or_null(
const LinkInfo& link_info) {
EXCEPTION_MARK;
Method* method_result = linktime_resolve_virtual_method(link_info, THREAD);
if (HAS_PENDING_EXCEPTION) {
CLEAR_PENDING_EXCEPTION;
return NULL;
} else {
return method_result;
}
}
Method* LinkResolver::resolve_virtual_call_or_null(
Klass* receiver_klass,
const LinkInfo& link_info) {
EXCEPTION_MARK;
CallInfo info;
resolve_virtual_call(info, Handle(), receiver_klass, link_info, false, THREAD);
if (HAS_PENDING_EXCEPTION) {
CLEAR_PENDING_EXCEPTION;
return NULL;
}
return info.selected_method();
}
Method* LinkResolver::resolve_interface_call_or_null(
Klass* receiver_klass,
const LinkInfo& link_info) {
EXCEPTION_MARK;
CallInfo info;
resolve_interface_call(info, Handle(), receiver_klass, link_info, false, THREAD);
if (HAS_PENDING_EXCEPTION) {
CLEAR_PENDING_EXCEPTION;
return NULL;
}
return info.selected_method();
}
int LinkResolver::resolve_virtual_vtable_index(Klass* receiver_klass,
const LinkInfo& link_info) {
EXCEPTION_MARK;
CallInfo info;
resolve_virtual_call(info, Handle(), receiver_klass, link_info,
/*check_null_or_abstract*/false, THREAD);
if (HAS_PENDING_EXCEPTION) {
CLEAR_PENDING_EXCEPTION;
return Method::invalid_vtable_index;
}
return info.vtable_index();
}
Method* LinkResolver::resolve_static_call_or_null(const LinkInfo& link_info) {
EXCEPTION_MARK;
CallInfo info;
resolve_static_call(info, link_info, /*initialize_class*/false, THREAD);
if (HAS_PENDING_EXCEPTION) {
CLEAR_PENDING_EXCEPTION;
return NULL;
}
return info.selected_method();
}
Method* LinkResolver::resolve_special_call_or_null(const LinkInfo& link_info) {
EXCEPTION_MARK;
CallInfo info;
resolve_special_call(info, Handle(), link_info, THREAD);
if (HAS_PENDING_EXCEPTION) {
CLEAR_PENDING_EXCEPTION;
return NULL;
}
return info.selected_method();
}
//------------------------------------------------------------------------------------------------------------------------
// ConstantPool entries
void LinkResolver::resolve_invoke(CallInfo& result, Handle recv, const constantPoolHandle& pool, int index, Bytecodes::Code byte, TRAPS) {
switch (byte) {
case Bytecodes::_invokestatic : resolve_invokestatic (result, pool, index, CHECK); break;
case Bytecodes::_invokespecial : resolve_invokespecial (result, recv, pool, index, CHECK); break;
case Bytecodes::_invokevirtual : resolve_invokevirtual (result, recv, pool, index, CHECK); break;
case Bytecodes::_invokehandle : resolve_invokehandle (result, pool, index, CHECK); break;
case Bytecodes::_invokedynamic : resolve_invokedynamic (result, pool, index, CHECK); break;
case Bytecodes::_invokeinterface: resolve_invokeinterface(result, recv, pool, index, CHECK); break;
default : break;
}
return;
}
void LinkResolver::resolve_invoke(CallInfo& result, Handle& recv,
const methodHandle& attached_method,
Bytecodes::Code byte, TRAPS) {
Klass* defc = attached_method->method_holder();
Symbol* name = attached_method->name();
Symbol* type = attached_method->signature();
LinkInfo link_info(defc, name, type);
switch(byte) {
case Bytecodes::_invokevirtual:
resolve_virtual_call(result, recv, recv->klass(), link_info,
/*check_null_and_abstract=*/true, CHECK);
break;
case Bytecodes::_invokeinterface:
resolve_interface_call(result, recv, recv->klass(), link_info,
/*check_null_and_abstract=*/true, CHECK);
break;
case Bytecodes::_invokestatic:
resolve_static_call(result, link_info, /*initialize_class=*/false, CHECK);
break;
case Bytecodes::_invokespecial:
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