1 /*
2 * Copyright (c) 2008, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.inline.hpp"
27 #include "classfile/stringTable.hpp"
28 #include "code/codeCache.hpp"
29 #include "code/dependencyContext.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "interpreter/interpreter.hpp"
32 #include "interpreter/oopMapCache.hpp"
33 #include "interpreter/linkResolver.hpp"
34 #include "memory/allocation.inline.hpp"
35 #include "memory/oopFactory.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "oops/objArrayOop.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "oops/typeArrayOop.inline.hpp"
40 #include "prims/methodHandles.hpp"
41 #include "runtime/compilationPolicy.hpp"
42 #include "runtime/javaCalls.hpp"
43 #include "runtime/jniHandles.inline.hpp"
44 #include "runtime/timerTrace.hpp"
45 #include "runtime/reflection.hpp"
46 #include "runtime/signature.hpp"
47 #include "runtime/stubRoutines.hpp"
48 #include "utilities/exceptions.hpp"
49
50
51 /*
52 * JSR 292 reference implementation: method handles
53 * The JDK 7 reference implementation represented method handle
54 * combinations as chains. Each link in the chain had a "vmentry"
55 * field which pointed at a bit of assembly code which performed
56 * one transformation before dispatching to the next link in the chain.
57 *
58 * The current reference implementation pushes almost all code generation
59 * responsibility to (trusted) Java code. A method handle contains a
60 * pointer to its "LambdaForm", which embodies all details of the method
61 * handle's behavior. The LambdaForm is a normal Java object, managed
62 * by a runtime coded in Java.
63 */
64
65 bool MethodHandles::_enabled = false; // set true after successful native linkage
66 MethodHandlesAdapterBlob* MethodHandles::_adapter_code = NULL;
67
68 /**
69 * Generates method handle adapters. Returns 'false' if memory allocation
70 * failed and true otherwise.
71 */
72 void MethodHandles::generate_adapters() {
73 assert(SystemDictionary::MethodHandle_klass() != NULL, "should be present");
74 assert(_adapter_code == NULL, "generate only once");
75
76 ResourceMark rm;
77 TraceTime timer("MethodHandles adapters generation", TRACETIME_LOG(Info, startuptime));
78 _adapter_code = MethodHandlesAdapterBlob::create(adapter_code_size);
79 CodeBuffer code(_adapter_code);
80 MethodHandlesAdapterGenerator g(&code);
81 g.generate();
82 code.log_section_sizes("MethodHandlesAdapterBlob");
83 }
84
85 //------------------------------------------------------------------------------
86 // MethodHandlesAdapterGenerator::generate
87 //
88 void MethodHandlesAdapterGenerator::generate() {
89 // Generate generic method handle adapters.
90 // Generate interpreter entries
91 for (Interpreter::MethodKind mk = Interpreter::method_handle_invoke_FIRST;
92 mk <= Interpreter::method_handle_invoke_LAST;
93 mk = Interpreter::MethodKind(1 + (int)mk)) {
94 vmIntrinsics::ID iid = Interpreter::method_handle_intrinsic(mk);
95 StubCodeMark mark(this, "MethodHandle::interpreter_entry", vmIntrinsics::name_at(iid));
96 address entry = MethodHandles::generate_method_handle_interpreter_entry(_masm, iid);
97 if (entry != NULL) {
98 Interpreter::set_entry_for_kind(mk, entry);
99 }
100 // If the entry is not set, it will throw AbstractMethodError.
101 }
102 }
103
104 void MethodHandles::set_enabled(bool z) {
105 if (_enabled != z) {
106 guarantee(z, "can only enable once");
107 _enabled = z;
108 }
109 }
110
111 // MemberName support
112
113 // import java_lang_invoke_MemberName.*
114 enum {
115 IS_METHOD = java_lang_invoke_MemberName::MN_IS_METHOD,
116 IS_CONSTRUCTOR = java_lang_invoke_MemberName::MN_IS_CONSTRUCTOR,
117 IS_FIELD = java_lang_invoke_MemberName::MN_IS_FIELD,
118 IS_TYPE = java_lang_invoke_MemberName::MN_IS_TYPE,
119 CALLER_SENSITIVE = java_lang_invoke_MemberName::MN_CALLER_SENSITIVE,
120 REFERENCE_KIND_SHIFT = java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT,
121 REFERENCE_KIND_MASK = java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK,
122 SEARCH_SUPERCLASSES = java_lang_invoke_MemberName::MN_SEARCH_SUPERCLASSES,
123 SEARCH_INTERFACES = java_lang_invoke_MemberName::MN_SEARCH_INTERFACES,
124 ALL_KINDS = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE
125 };
126
127 int MethodHandles::ref_kind_to_flags(int ref_kind) {
128 assert(ref_kind_is_valid(ref_kind), "%d", ref_kind);
129 int flags = (ref_kind << REFERENCE_KIND_SHIFT);
130 if (ref_kind_is_field(ref_kind)) {
131 flags |= IS_FIELD;
132 } else if (ref_kind_is_method(ref_kind)) {
133 flags |= IS_METHOD;
134 } else if (ref_kind == JVM_REF_newInvokeSpecial) {
135 flags |= IS_CONSTRUCTOR;
136 }
137 return flags;
138 }
139
140 Handle MethodHandles::resolve_MemberName_type(Handle mname, Klass* caller, TRAPS) {
141 Handle empty;
142 Handle type(THREAD, java_lang_invoke_MemberName::type(mname()));
143 if (!java_lang_String::is_instance_inlined(type())) {
144 return type; // already resolved
145 }
146 Symbol* signature = java_lang_String::as_symbol_or_null(type());
147 if (signature == NULL) {
148 return empty; // no such signature exists in the VM
149 }
150 Handle resolved;
151 int flags = java_lang_invoke_MemberName::flags(mname());
152 switch (flags & ALL_KINDS) {
153 case IS_METHOD:
154 case IS_CONSTRUCTOR:
155 resolved = SystemDictionary::find_method_handle_type(signature, caller, CHECK_(empty));
156 break;
157 case IS_FIELD:
158 resolved = SystemDictionary::find_field_handle_type(signature, caller, CHECK_(empty));
159 break;
160 default:
161 THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format", empty);
162 }
163 if (resolved.is_null()) {
164 THROW_MSG_(vmSymbols::java_lang_InternalError(), "bad MemberName type", empty);
165 }
166 return resolved;
167 }
168
169 oop MethodHandles::init_MemberName(Handle mname, Handle target, TRAPS) {
170 // This method is used from java.lang.invoke.MemberName constructors.
171 // It fills in the new MemberName from a java.lang.reflect.Member.
172 Thread* thread = Thread::current();
173 oop target_oop = target();
174 Klass* target_klass = target_oop->klass();
175 if (target_klass == SystemDictionary::reflect_Field_klass()) {
176 oop clazz = java_lang_reflect_Field::clazz(target_oop); // fd.field_holder()
177 int slot = java_lang_reflect_Field::slot(target_oop); // fd.index()
178 Klass* k = java_lang_Class::as_Klass(clazz);
179 if (k != NULL && k->is_instance_klass()) {
180 fieldDescriptor fd(InstanceKlass::cast(k), slot);
181 oop mname2 = init_field_MemberName(mname, fd);
182 if (mname2 != NULL) {
183 // Since we have the reified name and type handy, add them to the result.
184 if (java_lang_invoke_MemberName::name(mname2) == NULL)
185 java_lang_invoke_MemberName::set_name(mname2, java_lang_reflect_Field::name(target_oop));
186 if (java_lang_invoke_MemberName::type(mname2) == NULL)
187 java_lang_invoke_MemberName::set_type(mname2, java_lang_reflect_Field::type(target_oop));
188 }
189 return mname2;
190 }
191 } else if (target_klass == SystemDictionary::reflect_Method_klass()) {
192 oop clazz = java_lang_reflect_Method::clazz(target_oop);
193 int slot = java_lang_reflect_Method::slot(target_oop);
194 Klass* k = java_lang_Class::as_Klass(clazz);
195 if (k != NULL && k->is_instance_klass()) {
196 Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
197 if (m == NULL || is_signature_polymorphic(m->intrinsic_id()))
198 return NULL; // do not resolve unless there is a concrete signature
199 CallInfo info(m, k, CHECK_NULL);
200 return init_method_MemberName(mname, info);
201 }
202 } else if (target_klass == SystemDictionary::reflect_Constructor_klass()) {
203 oop clazz = java_lang_reflect_Constructor::clazz(target_oop);
204 int slot = java_lang_reflect_Constructor::slot(target_oop);
205 Klass* k = java_lang_Class::as_Klass(clazz);
206 if (k != NULL && k->is_instance_klass()) {
207 Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
208 if (m == NULL) return NULL;
209 CallInfo info(m, k, CHECK_NULL);
210 return init_method_MemberName(mname, info);
211 }
212 }
213 return NULL;
214 }
215
216 oop MethodHandles::init_method_MemberName(Handle mname, CallInfo& info) {
217 assert(info.resolved_appendix().is_null(), "only normal methods here");
218 methodHandle m = info.resolved_method();
219 assert(m.not_null(), "null method handle");
220 Klass* m_klass = m->method_holder();
221 assert(m_klass != NULL, "null holder for method handle");
222 int flags = (jushort)( m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS );
223 int vmindex = Method::invalid_vtable_index;
224
225 switch (info.call_kind()) {
226 case CallInfo::itable_call:
227 vmindex = info.itable_index();
228 // More importantly, the itable index only works with the method holder.
229 assert(m_klass->verify_itable_index(vmindex), "");
230 flags |= IS_METHOD | (JVM_REF_invokeInterface << REFERENCE_KIND_SHIFT);
231 if (TraceInvokeDynamic) {
232 ttyLocker ttyl;
233 ResourceMark rm;
234 tty->print_cr("memberName: invokeinterface method_holder::method: %s, itableindex: %d, access_flags:",
235 Method::name_and_sig_as_C_string(m->method_holder(), m->name(), m->signature()),
236 vmindex);
237 m->access_flags().print_on(tty);
238 if (!m->is_abstract()) {
239 tty->print("default");
240 }
241 tty->cr();
242 }
243 break;
244
245 case CallInfo::vtable_call:
246 vmindex = info.vtable_index();
247 flags |= IS_METHOD | (JVM_REF_invokeVirtual << REFERENCE_KIND_SHIFT);
248 assert(info.resolved_klass()->is_subtype_of(m_klass), "virtual call must be type-safe");
249 if (m_klass->is_interface()) {
250 // This is a vtable call to an interface method (abstract "miranda method" or default method).
251 // The vtable index is meaningless without a class (not interface) receiver type, so get one.
252 // (LinkResolver should help us figure this out.)
253 Klass* m_klass_non_interface = info.resolved_klass();
254 if (m_klass_non_interface->is_interface()) {
255 m_klass_non_interface = SystemDictionary::Object_klass();
256 #ifdef ASSERT
257 { ResourceMark rm;
258 Method* m2 = m_klass_non_interface->vtable().method_at(vmindex);
259 assert(m->name() == m2->name() && m->signature() == m2->signature(),
260 "at %d, %s != %s", vmindex,
261 m->name_and_sig_as_C_string(), m2->name_and_sig_as_C_string());
262 }
263 #endif //ASSERT
264 }
265 if (!m->is_public()) {
266 assert(m->is_public(), "virtual call must be to public interface method");
267 return NULL; // elicit an error later in product build
268 }
269 assert(info.resolved_klass()->is_subtype_of(m_klass_non_interface), "virtual call must be type-safe");
270 m_klass = m_klass_non_interface;
271 }
272 if (TraceInvokeDynamic) {
273 ttyLocker ttyl;
274 ResourceMark rm;
275 tty->print_cr("memberName: invokevirtual method_holder::method: %s, receiver: %s, vtableindex: %d, access_flags:",
276 Method::name_and_sig_as_C_string(m->method_holder(), m->name(), m->signature()),
277 m_klass->internal_name(), vmindex);
278 m->access_flags().print_on(tty);
279 if (m->is_default_method()) {
280 tty->print("default");
281 }
282 tty->cr();
283 }
284 break;
285
286 case CallInfo::direct_call:
287 vmindex = Method::nonvirtual_vtable_index;
288 if (m->is_static()) {
289 flags |= IS_METHOD | (JVM_REF_invokeStatic << REFERENCE_KIND_SHIFT);
290 } else if (m->is_initializer()) {
291 flags |= IS_CONSTRUCTOR | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);
292 } else {
293 flags |= IS_METHOD | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT);
294 }
295 break;
296
297 default: assert(false, "bad CallInfo"); return NULL;
298 }
299
300 // @CallerSensitive annotation detected
301 if (m->caller_sensitive()) {
302 flags |= CALLER_SENSITIVE;
303 }
304
305 Handle resolved_method = info.resolved_method_name();
306 assert(java_lang_invoke_ResolvedMethodName::vmtarget(resolved_method()) == m(),
307 "Should not change after link resolution");
308
309 oop mname_oop = mname();
310 java_lang_invoke_MemberName::set_flags (mname_oop, flags);
311 java_lang_invoke_MemberName::set_method (mname_oop, resolved_method());
312 java_lang_invoke_MemberName::set_vmindex(mname_oop, vmindex); // vtable/itable index
313 java_lang_invoke_MemberName::set_clazz (mname_oop, m_klass->java_mirror());
314 // Note: name and type can be lazily computed by resolve_MemberName,
315 // if Java code needs them as resolved String and MethodType objects.
316 // If relevant, the vtable or itable value is stored as vmindex.
317 // This is done eagerly, since it is readily available without
318 // constructing any new objects.
319 return mname();
320 }
321
322 oop MethodHandles::init_field_MemberName(Handle mname, fieldDescriptor& fd, bool is_setter) {
323 int flags = (jushort)( fd.access_flags().as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS );
324 flags |= IS_FIELD | ((fd.is_static() ? JVM_REF_getStatic : JVM_REF_getField) << REFERENCE_KIND_SHIFT);
325 if (is_setter) flags += ((JVM_REF_putField - JVM_REF_getField) << REFERENCE_KIND_SHIFT);
326 int vmindex = fd.offset(); // determines the field uniquely when combined with static bit
327
328 oop mname_oop = mname();
329 java_lang_invoke_MemberName::set_flags (mname_oop, flags);
330 java_lang_invoke_MemberName::set_method (mname_oop, NULL);
331 java_lang_invoke_MemberName::set_vmindex(mname_oop, vmindex);
332 java_lang_invoke_MemberName::set_clazz (mname_oop, fd.field_holder()->java_mirror());
333
334 oop type = field_signature_type_or_null(fd.signature());
335 oop name = field_name_or_null(fd.name());
336 if (name != NULL)
337 java_lang_invoke_MemberName::set_name(mname_oop, name);
338 if (type != NULL)
339 java_lang_invoke_MemberName::set_type(mname_oop, type);
340 // Note: name and type can be lazily computed by resolve_MemberName,
341 // if Java code needs them as resolved String and Class objects.
342 // Note that the incoming type oop might be pre-resolved (non-null).
343 // The base clazz and field offset (vmindex) must be eagerly stored,
344 // because they unambiguously identify the field.
345 // Although the fieldDescriptor::_index would also identify the field,
346 // we do not use it, because it is harder to decode.
347 // TO DO: maybe intern mname_oop
348 return mname();
349 }
350
351 // JVM 2.9 Special Methods:
352 // A method is signature polymorphic if and only if all of the following conditions hold :
353 // * It is declared in the java.lang.invoke.MethodHandle/VarHandle classes.
354 // * It has a single formal parameter of type Object[].
355 // * It has a return type of Object for a polymorphic return type, otherwise a fixed return type.
356 // * It has the ACC_VARARGS and ACC_NATIVE flags set.
357 bool MethodHandles::is_method_handle_invoke_name(Klass* klass, Symbol* name) {
358 if (klass == NULL)
359 return false;
360 // The following test will fail spuriously during bootstrap of MethodHandle itself:
361 // if (klass != SystemDictionary::MethodHandle_klass())
362 // Test the name instead:
363 if (klass->name() != vmSymbols::java_lang_invoke_MethodHandle() &&
364 klass->name() != vmSymbols::java_lang_invoke_VarHandle()) {
365 return false;
366 }
367
368 // Look up signature polymorphic method with polymorphic return type
369 Symbol* poly_sig = vmSymbols::object_array_object_signature();
370 InstanceKlass* iklass = InstanceKlass::cast(klass);
371 Method* m = iklass->find_method(name, poly_sig);
372 if (m != NULL) {
373 int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;
374 int flags = m->access_flags().as_int();
375 if ((flags & required) == required) {
376 return true;
377 }
378 }
379
380 // Look up signature polymorphic method with non-polymorphic (non Object) return type
381 int me;
382 int ms = iklass->find_method_by_name(name, &me);
383 if (ms == -1) return false;
384 for (; ms < me; ms++) {
385 Method* m = iklass->methods()->at(ms);
386 int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;
387 int flags = m->access_flags().as_int();
388 if ((flags & required) == required && ArgumentCount(m->signature()).size() == 1) {
389 return true;
390 }
391 }
392 return false;
393 }
394
395
396 Symbol* MethodHandles::signature_polymorphic_intrinsic_name(vmIntrinsics::ID iid) {
397 assert(is_signature_polymorphic_intrinsic(iid), "%d %s", iid, vmIntrinsics::name_at(iid));
398 switch (iid) {
399 case vmIntrinsics::_invokeBasic: return vmSymbols::invokeBasic_name();
400 case vmIntrinsics::_linkToVirtual: return vmSymbols::linkToVirtual_name();
401 case vmIntrinsics::_linkToStatic: return vmSymbols::linkToStatic_name();
402 case vmIntrinsics::_linkToSpecial: return vmSymbols::linkToSpecial_name();
403 case vmIntrinsics::_linkToInterface: return vmSymbols::linkToInterface_name();
404 default:
405 fatal("unexpected intrinsic id: %d %s", iid, vmIntrinsics::name_at(iid));
406 return 0;
407 }
408 }
409
410 Bytecodes::Code MethodHandles::signature_polymorphic_intrinsic_bytecode(vmIntrinsics::ID id) {
411 switch(id) {
412 case vmIntrinsics::_linkToVirtual: return Bytecodes::_invokevirtual;
413 case vmIntrinsics::_linkToInterface: return Bytecodes::_invokeinterface;
414 case vmIntrinsics::_linkToStatic: return Bytecodes::_invokestatic;
415 case vmIntrinsics::_linkToSpecial: return Bytecodes::_invokespecial;
416 case vmIntrinsics::_invokeBasic: return Bytecodes::_invokehandle;
417 default:
418 fatal("unexpected id: (%d) %s", (uint)id, vmIntrinsics::name_at(id));
419 return Bytecodes::_illegal;
420 }
421 }
422
423 int MethodHandles::signature_polymorphic_intrinsic_ref_kind(vmIntrinsics::ID iid) {
424 switch (iid) {
425 case vmIntrinsics::_invokeBasic: return 0;
426 case vmIntrinsics::_linkToVirtual: return JVM_REF_invokeVirtual;
427 case vmIntrinsics::_linkToStatic: return JVM_REF_invokeStatic;
428 case vmIntrinsics::_linkToSpecial: return JVM_REF_invokeSpecial;
429 case vmIntrinsics::_linkToInterface: return JVM_REF_invokeInterface;
430 default:
431 fatal("unexpected intrinsic id: %d %s", iid, vmIntrinsics::name_at(iid));
432 return 0;
433 }
434 }
435
436 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Symbol* name) {
437 vmSymbols::SID name_id = vmSymbols::find_sid(name);
438 switch (name_id) {
439 // The ID _invokeGeneric stands for all non-static signature-polymorphic methods, except built-ins.
440 case vmSymbols::VM_SYMBOL_ENUM_NAME(invoke_name): return vmIntrinsics::_invokeGeneric;
441 // The only built-in non-static signature-polymorphic method is MethodHandle.invokeBasic:
442 case vmSymbols::VM_SYMBOL_ENUM_NAME(invokeBasic_name): return vmIntrinsics::_invokeBasic;
443
444 // There is one static signature-polymorphic method for each JVM invocation mode.
445 case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToVirtual_name): return vmIntrinsics::_linkToVirtual;
446 case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToStatic_name): return vmIntrinsics::_linkToStatic;
447 case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToSpecial_name): return vmIntrinsics::_linkToSpecial;
448 case vmSymbols::VM_SYMBOL_ENUM_NAME(linkToInterface_name): return vmIntrinsics::_linkToInterface;
449 default: break;
450 }
451
452 // Cover the case of invokeExact and any future variants of invokeFoo.
453 Klass* mh_klass = SystemDictionary::well_known_klass(
454 SystemDictionary::WK_KLASS_ENUM_NAME(MethodHandle_klass) );
455 if (mh_klass != NULL && is_method_handle_invoke_name(mh_klass, name)) {
456 return vmIntrinsics::_invokeGeneric;
457 }
458
459 // Cover the case of methods on VarHandle.
460 Klass* vh_klass = SystemDictionary::well_known_klass(
461 SystemDictionary::WK_KLASS_ENUM_NAME(VarHandle_klass) );
462 if (vh_klass != NULL && is_method_handle_invoke_name(vh_klass, name)) {
463 return vmIntrinsics::_invokeGeneric;
464 }
465
466 // Note: The pseudo-intrinsic _compiledLambdaForm is never linked against.
467 // Instead it is used to mark lambda forms bound to invokehandle or invokedynamic.
468 return vmIntrinsics::_none;
469 }
470
471 vmIntrinsics::ID MethodHandles::signature_polymorphic_name_id(Klass* klass, Symbol* name) {
472 if (klass != NULL &&
473 (klass->name() == vmSymbols::java_lang_invoke_MethodHandle() ||
474 klass->name() == vmSymbols::java_lang_invoke_VarHandle())) {
475 vmIntrinsics::ID iid = signature_polymorphic_name_id(name);
476 if (iid != vmIntrinsics::_none)
477 return iid;
478 if (is_method_handle_invoke_name(klass, name))
479 return vmIntrinsics::_invokeGeneric;
480 }
481 return vmIntrinsics::_none;
482 }
483
484
485 // convert the external string or reflective type to an internal signature
486 Symbol* MethodHandles::lookup_signature(oop type_str, bool intern_if_not_found, TRAPS) {
487 if (java_lang_invoke_MethodType::is_instance(type_str)) {
488 return java_lang_invoke_MethodType::as_signature(type_str, intern_if_not_found, THREAD);
489 } else if (java_lang_Class::is_instance(type_str)) {
490 return java_lang_Class::as_signature(type_str, false, THREAD);
491 } else if (java_lang_String::is_instance_inlined(type_str)) {
492 if (intern_if_not_found) {
493 return java_lang_String::as_symbol(type_str, THREAD);
494 } else {
495 return java_lang_String::as_symbol_or_null(type_str);
496 }
497 } else {
498 THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized type", NULL);
499 }
500 }
501
502 static const char OBJ_SIG[] = "Ljava/lang/Object;";
503 enum { OBJ_SIG_LEN = 18 };
504
505 bool MethodHandles::is_basic_type_signature(Symbol* sig) {
506 assert(vmSymbols::object_signature()->utf8_length() == (int)OBJ_SIG_LEN, "");
507 assert(vmSymbols::object_signature()->equals(OBJ_SIG), "");
508 const int len = sig->utf8_length();
509 for (int i = 0; i < len; i++) {
510 switch (sig->byte_at(i)) {
511 case 'L':
512 // only java/lang/Object is valid here
513 if (sig->index_of_at(i, OBJ_SIG, OBJ_SIG_LEN) != i)
514 return false;
515 i += OBJ_SIG_LEN-1; //-1 because of i++ in loop
516 continue;
517 case '(': case ')': case 'V':
518 case 'I': case 'J': case 'F': case 'D':
519 continue;
520 //case '[':
521 //case 'Z': case 'B': case 'C': case 'S':
522 default:
523 return false;
524 }
525 }
526 return true;
527 }
528
529 Symbol* MethodHandles::lookup_basic_type_signature(Symbol* sig, bool keep_last_arg, TRAPS) {
530 Symbol* bsig = NULL;
531 if (sig == NULL) {
532 return sig;
533 } else if (is_basic_type_signature(sig)) {
534 sig->increment_refcount();
535 return sig; // that was easy
536 } else if (sig->byte_at(0) != '(') {
537 BasicType bt = char2type(sig->byte_at(0));
538 if (is_subword_type(bt)) {
539 bsig = vmSymbols::int_signature();
540 } else {
541 assert(bt == T_OBJECT || bt == T_ARRAY, "is_basic_type_signature was false");
542 bsig = vmSymbols::object_signature();
543 }
544 } else {
545 ResourceMark rm;
546 stringStream buffer(128);
547 buffer.put('(');
548 int arg_pos = 0, keep_arg_pos = -1;
549 if (keep_last_arg)
550 keep_arg_pos = ArgumentCount(sig).size() - 1;
551 for (SignatureStream ss(sig); !ss.is_done(); ss.next()) {
552 BasicType bt = ss.type();
553 size_t this_arg_pos = buffer.size();
554 if (ss.at_return_type()) {
555 buffer.put(')');
556 }
557 if (arg_pos == keep_arg_pos) {
558 buffer.write((char*) ss.raw_bytes(),
559 (int) ss.raw_length());
560 } else if (bt == T_OBJECT || bt == T_ARRAY) {
561 buffer.write(OBJ_SIG, OBJ_SIG_LEN);
562 } else {
563 if (is_subword_type(bt))
564 bt = T_INT;
565 buffer.put(type2char(bt));
566 }
567 arg_pos++;
568 }
569 const char* sigstr = buffer.base();
570 int siglen = (int) buffer.size();
571 bsig = SymbolTable::new_symbol(sigstr, siglen, THREAD);
572 }
573 assert(is_basic_type_signature(bsig) ||
574 // detune assert in case the injected argument is not a basic type:
575 keep_last_arg, "");
576 return bsig;
577 }
578
579 void MethodHandles::print_as_basic_type_signature_on(outputStream* st,
580 Symbol* sig,
581 bool keep_arrays,
582 bool keep_basic_names) {
583 st = st ? st : tty;
584 int len = sig->utf8_length();
585 int array = 0;
586 bool prev_type = false;
587 for (int i = 0; i < len; i++) {
588 char ch = sig->byte_at(i);
589 switch (ch) {
590 case '(': case ')':
591 prev_type = false;
592 st->put(ch);
593 continue;
594 case '[':
595 if (!keep_basic_names && keep_arrays)
596 st->put(ch);
597 array++;
598 continue;
599 case 'L':
600 {
601 if (prev_type) st->put(',');
602 int start = i+1, slash = start;
603 while (++i < len && (ch = sig->byte_at(i)) != ';') {
604 if (ch == '/' || ch == '.' || ch == '$') slash = i+1;
605 }
606 if (slash < i) start = slash;
607 if (!keep_basic_names) {
608 st->put('L');
609 } else {
610 for (int j = start; j < i; j++)
611 st->put(sig->byte_at(j));
612 prev_type = true;
613 }
614 break;
615 }
616 default:
617 {
618 if (array && char2type(ch) != T_ILLEGAL && !keep_arrays) {
619 ch = '[';
620 array = 0;
621 }
622 if (prev_type) st->put(',');
623 const char* n = NULL;
624 if (keep_basic_names)
625 n = type2name(char2type(ch));
626 if (n == NULL) {
627 // unknown letter, or we don't want to know its name
628 st->put(ch);
629 } else {
630 st->print("%s", n);
631 prev_type = true;
632 }
633 break;
634 }
635 }
636 // Switch break goes here to take care of array suffix:
637 if (prev_type) {
638 while (array > 0) {
639 st->print("[]");
640 --array;
641 }
642 }
643 array = 0;
644 }
645 }
646
647
648
649 static oop object_java_mirror() {
650 return SystemDictionary::Object_klass()->java_mirror();
651 }
652
653 oop MethodHandles::field_name_or_null(Symbol* s) {
654 if (s == NULL) return NULL;
655 return StringTable::lookup(s);
656 }
657
658 oop MethodHandles::field_signature_type_or_null(Symbol* s) {
659 if (s == NULL) return NULL;
660 BasicType bt = FieldType::basic_type(s);
661 if (is_java_primitive(bt)) {
662 assert(s->utf8_length() == 1, "");
663 return java_lang_Class::primitive_mirror(bt);
664 }
665 // Here are some more short cuts for common types.
666 // They are optional, since reference types can be resolved lazily.
667 if (bt == T_OBJECT) {
668 if (s == vmSymbols::object_signature()) {
669 return object_java_mirror();
670 } else if (s == vmSymbols::class_signature()) {
671 return SystemDictionary::Class_klass()->java_mirror();
672 } else if (s == vmSymbols::string_signature()) {
673 return SystemDictionary::String_klass()->java_mirror();
674 }
675 }
676 return NULL;
677 }
678
679
680 // An unresolved member name is a mere symbolic reference.
681 // Resolving it plants a vmtarget/vmindex in it,
682 // which refers directly to JVM internals.
683 Handle MethodHandles::resolve_MemberName(Handle mname, Klass* caller,
684 bool speculative_resolve, TRAPS) {
685 Handle empty;
686 assert(java_lang_invoke_MemberName::is_instance(mname()), "");
687
688 if (java_lang_invoke_MemberName::vmtarget(mname()) != NULL) {
689 // Already resolved.
690 DEBUG_ONLY(int vmindex = java_lang_invoke_MemberName::vmindex(mname()));
691 assert(vmindex >= Method::nonvirtual_vtable_index, "");
692 return mname;
693 }
694
695 Handle defc_oop(THREAD, java_lang_invoke_MemberName::clazz(mname()));
696 Handle name_str(THREAD, java_lang_invoke_MemberName::name( mname()));
697 Handle type_str(THREAD, java_lang_invoke_MemberName::type( mname()));
698 int flags = java_lang_invoke_MemberName::flags(mname());
699 int ref_kind = (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
700 if (!ref_kind_is_valid(ref_kind)) {
701 THROW_MSG_(vmSymbols::java_lang_InternalError(), "obsolete MemberName format", empty);
702 }
703
704 DEBUG_ONLY(int old_vmindex);
705 assert((old_vmindex = java_lang_invoke_MemberName::vmindex(mname())) == 0, "clean input");
706
707 if (defc_oop.is_null() || name_str.is_null() || type_str.is_null()) {
708 THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "nothing to resolve", empty);
709 }
710
711 InstanceKlass* defc = NULL;
712 {
713 Klass* defc_klass = java_lang_Class::as_Klass(defc_oop());
714 if (defc_klass == NULL) return empty; // a primitive; no resolution possible
715 if (!defc_klass->is_instance_klass()) {
716 if (!defc_klass->is_array_klass()) return empty;
717 defc_klass = SystemDictionary::Object_klass();
718 }
719 defc = InstanceKlass::cast(defc_klass);
720 }
721 if (defc == NULL) {
722 THROW_MSG_(vmSymbols::java_lang_InternalError(), "primitive class", empty);
723 }
724 defc->link_class(CHECK_(empty)); // possible safepoint
725
726 // convert the external string name to an internal symbol
727 TempNewSymbol name = java_lang_String::as_symbol_or_null(name_str());
728 if (name == NULL) return empty; // no such name
729 if (name == vmSymbols::class_initializer_name())
730 return empty; // illegal name
731
732 vmIntrinsics::ID mh_invoke_id = vmIntrinsics::_none;
733 if ((flags & ALL_KINDS) == IS_METHOD &&
734 (defc == SystemDictionary::MethodHandle_klass()) &&
735 (ref_kind == JVM_REF_invokeVirtual ||
736 ref_kind == JVM_REF_invokeSpecial ||
737 // static invocation mode is required for _linkToVirtual, etc.:
738 ref_kind == JVM_REF_invokeStatic)) {
739 vmIntrinsics::ID iid = signature_polymorphic_name_id(name);
740 if (iid != vmIntrinsics::_none &&
741 ((ref_kind == JVM_REF_invokeStatic) == is_signature_polymorphic_static(iid))) {
742 // Virtual methods invoke and invokeExact, plus internal invokers like _invokeBasic.
743 // For a static reference it could an internal linkage routine like _linkToVirtual, etc.
744 mh_invoke_id = iid;
745 }
746 }
747
748 // convert the external string or reflective type to an internal signature
749 TempNewSymbol type = lookup_signature(type_str(), (mh_invoke_id != vmIntrinsics::_none), CHECK_(empty));
750 if (type == NULL) return empty; // no such signature exists in the VM
751
752 LinkInfo::AccessCheck access_check = caller != NULL ?
753 LinkInfo::needs_access_check :
754 LinkInfo::skip_access_check;
755
756 // Time to do the lookup.
757 switch (flags & ALL_KINDS) {
758 case IS_METHOD:
759 {
760 CallInfo result;
761 LinkInfo link_info(defc, name, type, caller, access_check);
762 {
763 assert(!HAS_PENDING_EXCEPTION, "");
764 if (ref_kind == JVM_REF_invokeStatic) {
765 LinkResolver::resolve_static_call(result,
766 link_info, false, THREAD);
767 } else if (ref_kind == JVM_REF_invokeInterface) {
768 LinkResolver::resolve_interface_call(result, Handle(), defc,
769 link_info, false, THREAD);
770 } else if (mh_invoke_id != vmIntrinsics::_none) {
771 assert(!is_signature_polymorphic_static(mh_invoke_id), "");
772 LinkResolver::resolve_handle_call(result, link_info, THREAD);
773 } else if (ref_kind == JVM_REF_invokeSpecial) {
774 LinkResolver::resolve_special_call(result, Handle(),
775 link_info, THREAD);
776 } else if (ref_kind == JVM_REF_invokeVirtual) {
777 LinkResolver::resolve_virtual_call(result, Handle(), defc,
778 link_info, false, THREAD);
779 } else {
780 assert(false, "ref_kind=%d", ref_kind);
781 }
782 if (HAS_PENDING_EXCEPTION) {
783 if (speculative_resolve) {
784 CLEAR_PENDING_EXCEPTION;
785 }
786 return empty;
787 }
788 }
789 if (result.resolved_appendix().not_null()) {
790 // The resolved MemberName must not be accompanied by an appendix argument,
791 // since there is no way to bind this value into the MemberName.
792 // Caller is responsible to prevent this from happening.
793 THROW_MSG_(vmSymbols::java_lang_InternalError(), "appendix", empty);
794 }
795 result.set_resolved_method_name(CHECK_(empty));
796 oop mname2 = init_method_MemberName(mname, result);
797 return Handle(THREAD, mname2);
798 }
799 case IS_CONSTRUCTOR:
800 {
801 CallInfo result;
802 LinkInfo link_info(defc, name, type, caller, access_check);
803 {
804 assert(!HAS_PENDING_EXCEPTION, "");
805 if (name == vmSymbols::object_initializer_name()) {
806 LinkResolver::resolve_special_call(result, Handle(), link_info, THREAD);
807 } else {
808 break; // will throw after end of switch
809 }
810 if (HAS_PENDING_EXCEPTION) {
811 if (speculative_resolve) {
812 CLEAR_PENDING_EXCEPTION;
813 }
814 return empty;
815 }
816 }
817 assert(result.is_statically_bound(), "");
818 result.set_resolved_method_name(CHECK_(empty));
819 oop mname2 = init_method_MemberName(mname, result);
820 return Handle(THREAD, mname2);
821 }
822 case IS_FIELD:
823 {
824 fieldDescriptor result; // find_field initializes fd if found
825 {
826 assert(!HAS_PENDING_EXCEPTION, "");
827 LinkInfo link_info(defc, name, type, caller, LinkInfo::skip_access_check);
828 LinkResolver::resolve_field(result, link_info, Bytecodes::_nop, false, THREAD);
829 if (HAS_PENDING_EXCEPTION) {
830 if (speculative_resolve) {
831 CLEAR_PENDING_EXCEPTION;
832 }
833 return empty;
834 }
835 }
836 oop mname2 = init_field_MemberName(mname, result, ref_kind_is_setter(ref_kind));
837 return Handle(THREAD, mname2);
838 }
839 default:
840 THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format", empty);
841 }
842
843 return empty;
844 }
845
846 // Conversely, a member name which is only initialized from JVM internals
847 // may have null defc, name, and type fields.
848 // Resolving it plants a vmtarget/vmindex in it,
849 // which refers directly to JVM internals.
850 void MethodHandles::expand_MemberName(Handle mname, int suppress, TRAPS) {
851 assert(java_lang_invoke_MemberName::is_instance(mname()), "");
852
853 bool have_defc = (java_lang_invoke_MemberName::clazz(mname()) != NULL);
854 bool have_name = (java_lang_invoke_MemberName::name(mname()) != NULL);
855 bool have_type = (java_lang_invoke_MemberName::type(mname()) != NULL);
856 int flags = java_lang_invoke_MemberName::flags(mname());
857
858 if (suppress != 0) {
859 if (suppress & _suppress_defc) have_defc = true;
860 if (suppress & _suppress_name) have_name = true;
861 if (suppress & _suppress_type) have_type = true;
862 }
863
864 if (have_defc && have_name && have_type) return; // nothing needed
865
866 switch (flags & ALL_KINDS) {
867 case IS_METHOD:
868 case IS_CONSTRUCTOR:
869 {
870 Method* vmtarget = java_lang_invoke_MemberName::vmtarget(mname());
871 if (vmtarget == NULL) {
872 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand");
873 }
874 methodHandle m(THREAD, vmtarget);
875 DEBUG_ONLY(vmtarget = NULL); // safety
876 if (!have_defc) {
877 InstanceKlass* defc = m->method_holder();
878 java_lang_invoke_MemberName::set_clazz(mname(), defc->java_mirror());
879 }
880 if (!have_name) {
881 //not java_lang_String::create_from_symbol; let's intern member names
882 oop name = StringTable::intern(m->name(), CHECK);
883 java_lang_invoke_MemberName::set_name(mname(), name);
884 }
885 if (!have_type) {
886 Handle type = java_lang_String::create_from_symbol(m->signature(), CHECK);
887 java_lang_invoke_MemberName::set_type(mname(), type());
888 }
889 return;
890 }
891 case IS_FIELD:
892 {
893 oop clazz = java_lang_invoke_MemberName::clazz(mname());
894 if (clazz == NULL) {
895 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand (as field)");
896 }
897 InstanceKlass* defc = InstanceKlass::cast(java_lang_Class::as_Klass(clazz));
898 DEBUG_ONLY(clazz = NULL); // safety
899 int vmindex = java_lang_invoke_MemberName::vmindex(mname());
900 bool is_static = ((flags & JVM_ACC_STATIC) != 0);
901 fieldDescriptor fd; // find_field initializes fd if found
902 if (!defc->find_field_from_offset(vmindex, is_static, &fd))
903 break; // cannot expand
904 if (!have_name) {
905 //not java_lang_String::create_from_symbol; let's intern member names
906 oop name = StringTable::intern(fd.name(), CHECK);
907 java_lang_invoke_MemberName::set_name(mname(), name);
908 }
909 if (!have_type) {
910 // If it is a primitive field type, don't mess with short strings like "I".
911 Handle type (THREAD, field_signature_type_or_null(fd.signature()));
912 if (type.is_null()) {
913 type = java_lang_String::create_from_symbol(fd.signature(), CHECK);
914 }
915 java_lang_invoke_MemberName::set_type(mname(), type());
916 }
917 return;
918 }
919 }
920 THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
921 }
922
923 int MethodHandles::find_MemberNames(Klass* k,
924 Symbol* name, Symbol* sig,
925 int mflags, Klass* caller,
926 int skip, objArrayHandle results, TRAPS) {
927 // %%% take caller into account!
928
929 Thread* thread = Thread::current();
930
931 if (k == NULL || !k->is_instance_klass()) return -1;
932
933 int rfill = 0, rlimit = results->length(), rskip = skip;
934 // overflow measurement:
935 int overflow = 0, overflow_limit = MAX2(1000, rlimit);
936
937 int match_flags = mflags;
938 bool search_superc = ((match_flags & SEARCH_SUPERCLASSES) != 0);
939 bool search_intfc = ((match_flags & SEARCH_INTERFACES) != 0);
940 bool local_only = !(search_superc | search_intfc);
941 bool classes_only = false;
942
943 if (name != NULL) {
944 if (name->utf8_length() == 0) return 0; // a match is not possible
945 }
946 if (sig != NULL) {
947 if (sig->utf8_length() == 0) return 0; // a match is not possible
948 if (sig->byte_at(0) == '(')
949 match_flags &= ~(IS_FIELD | IS_TYPE);
950 else
951 match_flags &= ~(IS_CONSTRUCTOR | IS_METHOD);
952 }
953
954 if ((match_flags & IS_TYPE) != 0) {
955 // NYI, and Core Reflection works quite well for this query
956 }
957
958 if ((match_flags & IS_FIELD) != 0) {
959 InstanceKlass* ik = InstanceKlass::cast(k);
960 for (FieldStream st(ik, local_only, !search_intfc); !st.eos(); st.next()) {
961 if (name != NULL && st.name() != name)
962 continue;
963 if (sig != NULL && st.signature() != sig)
964 continue;
965 // passed the filters
966 if (rskip > 0) {
967 --rskip;
968 } else if (rfill < rlimit) {
969 Handle result(thread, results->obj_at(rfill++));
970 if (!java_lang_invoke_MemberName::is_instance(result()))
971 return -99; // caller bug!
972 oop saved = MethodHandles::init_field_MemberName(result, st.field_descriptor());
973 if (saved != result())
974 results->obj_at_put(rfill-1, saved); // show saved instance to user
975 } else if (++overflow >= overflow_limit) {
976 match_flags = 0; break; // got tired of looking at overflow
977 }
978 }
979 }
980
981 if ((match_flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {
982 // watch out for these guys:
983 Symbol* init_name = vmSymbols::object_initializer_name();
984 Symbol* clinit_name = vmSymbols::class_initializer_name();
985 if (name == clinit_name) clinit_name = NULL; // hack for exposing <clinit>
986 bool negate_name_test = false;
987 // fix name so that it captures the intention of IS_CONSTRUCTOR
988 if (!(match_flags & IS_METHOD)) {
989 // constructors only
990 if (name == NULL) {
991 name = init_name;
992 } else if (name != init_name) {
993 return 0; // no constructors of this method name
994 }
995 } else if (!(match_flags & IS_CONSTRUCTOR)) {
996 // methods only
997 if (name == NULL) {
998 name = init_name;
999 negate_name_test = true; // if we see the name, we *omit* the entry
1000 } else if (name == init_name) {
1001 return 0; // no methods of this constructor name
1002 }
1003 } else {
1004 // caller will accept either sort; no need to adjust name
1005 }
1006 InstanceKlass* ik = InstanceKlass::cast(k);
1007 for (MethodStream st(ik, local_only, !search_intfc); !st.eos(); st.next()) {
1008 Method* m = st.method();
1009 Symbol* m_name = m->name();
1010 if (m_name == clinit_name)
1011 continue;
1012 if (name != NULL && ((m_name != name) ^ negate_name_test))
1013 continue;
1014 if (sig != NULL && m->signature() != sig)
1015 continue;
1016 // passed the filters
1017 if (rskip > 0) {
1018 --rskip;
1019 } else if (rfill < rlimit) {
1020 Handle result(thread, results->obj_at(rfill++));
1021 if (!java_lang_invoke_MemberName::is_instance(result()))
1022 return -99; // caller bug!
1023 CallInfo info(m, NULL, CHECK_0);
1024 oop saved = MethodHandles::init_method_MemberName(result, info);
1025 if (saved != result())
1026 results->obj_at_put(rfill-1, saved); // show saved instance to user
1027 } else if (++overflow >= overflow_limit) {
1028 match_flags = 0; break; // got tired of looking at overflow
1029 }
1030 }
1031 }
1032
1033 // return number of elements we at leasted wanted to initialize
1034 return rfill + overflow;
1035 }
1036
1037 // Is it safe to remove stale entries from a dependency list?
1038 static bool safe_to_expunge() {
1039 // Since parallel GC threads can concurrently iterate over a dependency
1040 // list during safepoint, it is safe to remove entries only when
1041 // CodeCache lock is held.
1042 return CodeCache_lock->owned_by_self();
1043 }
1044
1045 void MethodHandles::add_dependent_nmethod(oop call_site, nmethod* nm) {
1046 assert_locked_or_safepoint(CodeCache_lock);
1047
1048 oop context = java_lang_invoke_CallSite::context(call_site);
1049 DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);
1050 // Try to purge stale entries on updates.
1051 // Since GC doesn't clean dependency contexts rooted at CallSiteContext objects,
1052 // in order to avoid memory leak, stale entries are purged whenever a dependency list
1053 // is changed (both on addition and removal). Though memory reclamation is delayed,
1054 // it avoids indefinite memory usage growth.
1055 deps.add_dependent_nmethod(nm, /*expunge_stale_entries=*/safe_to_expunge());
1056 }
1057
1058 void MethodHandles::remove_dependent_nmethod(oop call_site, nmethod* nm) {
1059 assert_locked_or_safepoint(CodeCache_lock);
1060
1061 oop context = java_lang_invoke_CallSite::context(call_site);
1062 DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);
1063 deps.remove_dependent_nmethod(nm, /*expunge_stale_entries=*/safe_to_expunge());
1064 }
1065
1066 void MethodHandles::flush_dependent_nmethods(Handle call_site, Handle target) {
1067 assert_lock_strong(Compile_lock);
1068
1069 int marked = 0;
1070 CallSiteDepChange changes(call_site, target);
1071 {
1072 NoSafepointVerifier nsv;
1073 MutexLockerEx mu2(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1074
1075 oop context = java_lang_invoke_CallSite::context(call_site());
1076 DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context);
1077 marked = deps.mark_dependent_nmethods(changes);
1078 }
1079 if (marked > 0) {
1080 // At least one nmethod has been marked for deoptimization.
1081 VM_Deoptimize op;
1082 VMThread::execute(&op);
1083 }
1084 }
1085
1086 void MethodHandles::trace_method_handle_interpreter_entry(MacroAssembler* _masm, vmIntrinsics::ID iid) {
1087 if (TraceMethodHandles) {
1088 const char* name = vmIntrinsics::name_at(iid);
1089 if (*name == '_') name += 1;
1090 const size_t len = strlen(name) + 50;
1091 char* qname = NEW_C_HEAP_ARRAY(char, len, mtInternal);
1092 const char* suffix = "";
1093 if (is_signature_polymorphic(iid)) {
1094 if (is_signature_polymorphic_static(iid))
1095 suffix = "/static";
1096 else
1097 suffix = "/private";
1098 }
1099 jio_snprintf(qname, len, "MethodHandle::interpreter_entry::%s%s", name, suffix);
1100 trace_method_handle(_masm, qname);
1101 // Note: Don't free the allocated char array because it's used
1102 // during runtime.
1103 }
1104 }
1105
1106 //
1107 // Here are the native methods in java.lang.invoke.MethodHandleNatives
1108 // They are the private interface between this JVM and the HotSpot-specific
1109 // Java code that implements JSR 292 method handles.
1110 //
1111 // Note: We use a JVM_ENTRY macro to define each of these, for this is the way
1112 // that intrinsic (non-JNI) native methods are defined in HotSpot.
1113 //
1114
1115 #ifndef PRODUCT
1116 #define EACH_NAMED_CON(template, requirement) \
1117 template(java_lang_invoke_MemberName,MN_IS_METHOD) \
1118 template(java_lang_invoke_MemberName,MN_IS_CONSTRUCTOR) \
1119 template(java_lang_invoke_MemberName,MN_IS_FIELD) \
1120 template(java_lang_invoke_MemberName,MN_IS_TYPE) \
1121 template(java_lang_invoke_MemberName,MN_CALLER_SENSITIVE) \
1122 template(java_lang_invoke_MemberName,MN_SEARCH_SUPERCLASSES) \
1123 template(java_lang_invoke_MemberName,MN_SEARCH_INTERFACES) \
1124 template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_SHIFT) \
1125 template(java_lang_invoke_MemberName,MN_REFERENCE_KIND_MASK) \
1126 /*end*/
1127
1128 #define IGNORE_REQ(req_expr) /* req_expr */
1129 #define ONE_PLUS(scope,value) 1+
1130 static const int con_value_count = EACH_NAMED_CON(ONE_PLUS, IGNORE_REQ) 0;
1131 #define VALUE_COMMA(scope,value) scope::value,
1132 static const int con_values[con_value_count+1] = { EACH_NAMED_CON(VALUE_COMMA, IGNORE_REQ) 0 };
1133 #define STRING_NULL(scope,value) #value "\0"
1134 static const char con_names[] = { EACH_NAMED_CON(STRING_NULL, IGNORE_REQ) };
1135
1136 static bool advertise_con_value(int which) {
1137 if (which < 0) return false;
1138 bool ok = true;
1139 int count = 0;
1140 #define INC_COUNT(scope,value) \
1141 ++count;
1142 #define CHECK_REQ(req_expr) \
1143 if (which < count) return ok; \
1144 ok = (req_expr);
1145 EACH_NAMED_CON(INC_COUNT, CHECK_REQ);
1146 #undef INC_COUNT
1147 #undef CHECK_REQ
1148 assert(count == con_value_count, "");
1149 if (which < count) return ok;
1150 return false;
1151 }
1152
1153 #undef ONE_PLUS
1154 #undef VALUE_COMMA
1155 #undef STRING_NULL
1156 #undef EACH_NAMED_CON
1157 #endif // PRODUCT
1158
1159 JVM_ENTRY(jint, MHN_getNamedCon(JNIEnv *env, jobject igcls, jint which, jobjectArray box_jh)) {
1160 #ifndef PRODUCT
1161 if (advertise_con_value(which)) {
1162 assert(which >= 0 && which < con_value_count, "");
1163 int con = con_values[which];
1164 objArrayHandle box(THREAD, (objArrayOop) JNIHandles::resolve(box_jh));
1165 if (box.not_null() && box->klass() == Universe::objectArrayKlassObj() && box->length() > 0) {
1166 const char* str = &con_names[0];
1167 for (int i = 0; i < which; i++)
1168 str += strlen(str) + 1; // skip name and null
1169 oop name = java_lang_String::create_oop_from_str(str, CHECK_0); // possible safepoint
1170 box->obj_at_put(0, name);
1171 }
1172 return con;
1173 }
1174 #endif
1175 return 0;
1176 }
1177 JVM_END
1178
1179 // void init(MemberName self, AccessibleObject ref)
1180 JVM_ENTRY(void, MHN_init_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jobject target_jh)) {
1181 if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
1182 if (target_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "target is null"); }
1183 Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1184 Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
1185 MethodHandles::init_MemberName(mname, target, CHECK);
1186 }
1187 JVM_END
1188
1189 // void expand(MemberName self)
1190 JVM_ENTRY(void, MHN_expand_Mem(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1191 if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
1192 Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1193 MethodHandles::expand_MemberName(mname, 0, CHECK);
1194 }
1195 JVM_END
1196
1197 // void resolve(MemberName self, Class<?> caller)
1198 JVM_ENTRY(jobject, MHN_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh,
1199 jboolean speculative_resolve)) {
1200 if (mname_jh == NULL) { THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "mname is null"); }
1201 Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1202
1203 // The trusted Java code that calls this method should already have performed
1204 // access checks on behalf of the given caller. But, we can verify this.
1205 if (VerifyMethodHandles && caller_jh != NULL &&
1206 java_lang_invoke_MemberName::clazz(mname()) != NULL) {
1207 Klass* reference_klass = java_lang_Class::as_Klass(java_lang_invoke_MemberName::clazz(mname()));
1208 if (reference_klass != NULL && reference_klass->is_objArray_klass()) {
1209 reference_klass = ObjArrayKlass::cast(reference_klass)->bottom_klass();
1210 }
1211
1212 // Reflection::verify_class_access can only handle instance classes.
1213 if (reference_klass != NULL && reference_klass->is_instance_klass()) {
1214 // Emulate LinkResolver::check_klass_accessability.
1215 Klass* caller = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(caller_jh));
1216 if (caller != SystemDictionary::Object_klass()
1217 && Reflection::verify_class_access(caller,
1218 InstanceKlass::cast(reference_klass),
1219 true) != Reflection::ACCESS_OK) {
1220 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), reference_klass->external_name());
1221 }
1222 }
1223 }
1224
1225 Klass* caller = caller_jh == NULL ? NULL :
1226 java_lang_Class::as_Klass(JNIHandles::resolve_non_null(caller_jh));
1227 Handle resolved = MethodHandles::resolve_MemberName(mname, caller, speculative_resolve,
1228 CHECK_NULL);
1229
1230 if (resolved.is_null()) {
1231 int flags = java_lang_invoke_MemberName::flags(mname());
1232 int ref_kind = (flags >> REFERENCE_KIND_SHIFT) & REFERENCE_KIND_MASK;
1233 if (!MethodHandles::ref_kind_is_valid(ref_kind)) {
1234 THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "obsolete MemberName format");
1235 }
1236 if (speculative_resolve) {
1237 assert(!HAS_PENDING_EXCEPTION, "");
1238 return NULL;
1239 }
1240 if ((flags & ALL_KINDS) == IS_FIELD) {
1241 THROW_MSG_NULL(vmSymbols::java_lang_NoSuchFieldError(), "field resolution failed");
1242 } else if ((flags & ALL_KINDS) == IS_METHOD ||
1243 (flags & ALL_KINDS) == IS_CONSTRUCTOR) {
1244 THROW_MSG_NULL(vmSymbols::java_lang_NoSuchMethodError(), "method resolution failed");
1245 } else {
1246 THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "resolution failed");
1247 }
1248 }
1249
1250 return JNIHandles::make_local(THREAD, resolved());
1251 }
1252 JVM_END
1253
1254 static jlong find_member_field_offset(oop mname, bool must_be_static, TRAPS) {
1255 if (mname == NULL ||
1256 java_lang_invoke_MemberName::clazz(mname) == NULL) {
1257 THROW_MSG_0(vmSymbols::java_lang_InternalError(), "mname not resolved");
1258 } else {
1259 int flags = java_lang_invoke_MemberName::flags(mname);
1260 if ((flags & IS_FIELD) != 0 &&
1261 (must_be_static
1262 ? (flags & JVM_ACC_STATIC) != 0
1263 : (flags & JVM_ACC_STATIC) == 0)) {
1264 int vmindex = java_lang_invoke_MemberName::vmindex(mname);
1265 return (jlong) vmindex;
1266 }
1267 }
1268 const char* msg = (must_be_static ? "static field required" : "non-static field required");
1269 THROW_MSG_0(vmSymbols::java_lang_InternalError(), msg);
1270 return 0;
1271 }
1272
1273 JVM_ENTRY(jlong, MHN_objectFieldOffset(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1274 return find_member_field_offset(JNIHandles::resolve(mname_jh), false, THREAD);
1275 }
1276 JVM_END
1277
1278 JVM_ENTRY(jlong, MHN_staticFieldOffset(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1279 return find_member_field_offset(JNIHandles::resolve(mname_jh), true, THREAD);
1280 }
1281 JVM_END
1282
1283 JVM_ENTRY(jobject, MHN_staticFieldBase(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1284 // use the other function to perform sanity checks:
1285 jlong ignore = find_member_field_offset(JNIHandles::resolve(mname_jh), true, CHECK_NULL);
1286 oop clazz = java_lang_invoke_MemberName::clazz(JNIHandles::resolve_non_null(mname_jh));
1287 return JNIHandles::make_local(THREAD, clazz);
1288 }
1289 JVM_END
1290
1291 JVM_ENTRY(jobject, MHN_getMemberVMInfo(JNIEnv *env, jobject igcls, jobject mname_jh)) {
1292 if (mname_jh == NULL) return NULL;
1293 Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
1294 intptr_t vmindex = java_lang_invoke_MemberName::vmindex(mname());
1295 objArrayHandle result = oopFactory::new_objArray_handle(SystemDictionary::Object_klass(), 2, CHECK_NULL);
1296 jvalue vmindex_value; vmindex_value.j = (long)vmindex;
1297 oop x = java_lang_boxing_object::create(T_LONG, &vmindex_value, CHECK_NULL);
1298 result->obj_at_put(0, x);
1299
1300 int flags = java_lang_invoke_MemberName::flags(mname());
1301 if ((flags & IS_FIELD) != 0) {
1302 x = java_lang_invoke_MemberName::clazz(mname());
1303 } else {
1304 Method* vmtarget = java_lang_invoke_MemberName::vmtarget(mname());
1305 assert(vmtarget != NULL && vmtarget->is_method(), "vmtarget is only method");
1306 x = mname();
1307 }
1308 result->obj_at_put(1, x);
1309 return JNIHandles::make_local(env, result());
1310 }
1311 JVM_END
1312
1313
1314
1315 // static native int getMembers(Class<?> defc, String matchName, String matchSig,
1316 // int matchFlags, Class<?> caller, int skip, MemberName[] results);
1317 JVM_ENTRY(jint, MHN_getMembers(JNIEnv *env, jobject igcls,
1318 jclass clazz_jh, jstring name_jh, jstring sig_jh,
1319 int mflags, jclass caller_jh, jint skip, jobjectArray results_jh)) {
1320 if (clazz_jh == NULL || results_jh == NULL) return -1;
1321 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz_jh));
1322
1323 objArrayHandle results(THREAD, (objArrayOop) JNIHandles::resolve(results_jh));
1324 if (results.is_null() || !results->is_objArray()) return -1;
1325
1326 TempNewSymbol name = NULL;
1327 TempNewSymbol sig = NULL;
1328 if (name_jh != NULL) {
1329 name = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(name_jh));
1330 if (name == NULL) return 0; // a match is not possible
1331 }
1332 if (sig_jh != NULL) {
1333 sig = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(sig_jh));
1334 if (sig == NULL) return 0; // a match is not possible
1335 }
1336
1337 Klass* caller = NULL;
1338 if (caller_jh != NULL) {
1339 oop caller_oop = JNIHandles::resolve_non_null(caller_jh);
1340 if (!java_lang_Class::is_instance(caller_oop)) return -1;
1341 caller = java_lang_Class::as_Klass(caller_oop);
1342 }
1343
1344 if (name != NULL && sig != NULL && results.not_null()) {
1345 // try a direct resolve
1346 // %%% TO DO
1347 }
1348
1349 int res = MethodHandles::find_MemberNames(k, name, sig, mflags,
1350 caller, skip, results, CHECK_0);
1351 // TO DO: expand at least some of the MemberNames, to avoid massive callbacks
1352 return res;
1353 }
1354 JVM_END
1355
1356 JVM_ENTRY(void, MHN_setCallSiteTargetNormal(JNIEnv* env, jobject igcls, jobject call_site_jh, jobject target_jh)) {
1357 Handle call_site(THREAD, JNIHandles::resolve_non_null(call_site_jh));
1358 Handle target (THREAD, JNIHandles::resolve_non_null(target_jh));
1359 {
1360 // Walk all nmethods depending on this call site.
1361 MutexLocker mu(Compile_lock, thread);
1362 MethodHandles::flush_dependent_nmethods(call_site, target);
1363 java_lang_invoke_CallSite::set_target(call_site(), target());
1364 }
1365 }
1366 JVM_END
1367
1368 JVM_ENTRY(void, MHN_setCallSiteTargetVolatile(JNIEnv* env, jobject igcls, jobject call_site_jh, jobject target_jh)) {
1369 Handle call_site(THREAD, JNIHandles::resolve_non_null(call_site_jh));
1370 Handle target (THREAD, JNIHandles::resolve_non_null(target_jh));
1371 {
1372 // Walk all nmethods depending on this call site.
1373 MutexLocker mu(Compile_lock, thread);
1374 MethodHandles::flush_dependent_nmethods(call_site, target);
1375 java_lang_invoke_CallSite::set_target_volatile(call_site(), target());
1376 }
1377 }
1378 JVM_END
1379
1380 JVM_ENTRY(void, MHN_copyOutBootstrapArguments(JNIEnv* env, jobject igcls,
1381 jobject caller_jh, jintArray index_info_jh,
1382 jint start, jint end,
1383 jobjectArray buf_jh, jint pos,
1384 jboolean resolve, jobject ifna_jh)) {
1385 Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller_jh));
1386 if (caller_k == NULL || !caller_k->is_instance_klass()) {
1387 THROW_MSG(vmSymbols::java_lang_InternalError(), "bad caller");
1388 }
1389 InstanceKlass* caller = InstanceKlass::cast(caller_k);
1390 typeArrayOop index_info_oop = (typeArrayOop) JNIHandles::resolve(index_info_jh);
1391 if (index_info_oop == NULL ||
1392 index_info_oop->klass() != Universe::intArrayKlassObj() ||
1393 typeArrayOop(index_info_oop)->length() < 2) {
1394 THROW_MSG(vmSymbols::java_lang_InternalError(), "bad index info (0)");
1395 }
1396 typeArrayHandle index_info(THREAD, index_info_oop);
1397 int bss_index_in_pool = index_info->int_at(1);
1398 // While we are here, take a quick look at the index info:
1399 if (bss_index_in_pool <= 0 ||
1400 bss_index_in_pool >= caller->constants()->length() ||
1401 index_info->int_at(0)
1402 != caller->constants()->invoke_dynamic_argument_count_at(bss_index_in_pool)) {
1403 THROW_MSG(vmSymbols::java_lang_InternalError(), "bad index info (1)");
1404 }
1405 objArrayHandle buf(THREAD, (objArrayOop) JNIHandles::resolve(buf_jh));
1406 if (start < 0) {
1407 for (int pseudo_index = -4; pseudo_index < 0; pseudo_index++) {
1408 if (start == pseudo_index) {
1409 if (start >= end || 0 > pos || pos >= buf->length()) break;
1410 oop pseudo_arg = NULL;
1411 switch (pseudo_index) {
1412 case -4: // bootstrap method
1413 {
1414 int bsm_index = caller->constants()->invoke_dynamic_bootstrap_method_ref_index_at(bss_index_in_pool);
1415 pseudo_arg = caller->constants()->resolve_possibly_cached_constant_at(bsm_index, CHECK);
1416 break;
1417 }
1418 case -3: // name
1419 {
1420 Symbol* name = caller->constants()->name_ref_at(bss_index_in_pool);
1421 Handle str = java_lang_String::create_from_symbol(name, CHECK);
1422 pseudo_arg = str();
1423 break;
1424 }
1425 case -2: // type
1426 {
1427 Symbol* type = caller->constants()->signature_ref_at(bss_index_in_pool);
1428 Handle th;
1429 if (type->byte_at(0) == '(') {
1430 th = SystemDictionary::find_method_handle_type(type, caller, CHECK);
1431 } else {
1432 th = SystemDictionary::find_java_mirror_for_type(type, caller, SignatureStream::NCDFError, CHECK);
1433 }
1434 pseudo_arg = th();
1435 break;
1436 }
1437 case -1: // argument count
1438 {
1439 int argc = caller->constants()->invoke_dynamic_argument_count_at(bss_index_in_pool);
1440 jvalue argc_value; argc_value.i = (jint)argc;
1441 pseudo_arg = java_lang_boxing_object::create(T_INT, &argc_value, CHECK);
1442 break;
1443 }
1444 }
1445
1446 // Store the pseudo-argument, and advance the pointers.
1447 buf->obj_at_put(pos++, pseudo_arg);
1448 ++start;
1449 }
1450 }
1451 // When we are done with this there may be regular arguments to process too.
1452 }
1453 Handle ifna(THREAD, JNIHandles::resolve(ifna_jh));
1454 caller->constants()->
1455 copy_bootstrap_arguments_at(bss_index_in_pool,
1456 start, end, buf, pos,
1457 (resolve == JNI_TRUE), ifna, CHECK);
1458 }
1459 JVM_END
1460
1461 // It is called by a Cleaner object which ensures that dropped CallSites properly
1462 // deallocate their dependency information.
1463 JVM_ENTRY(void, MHN_clearCallSiteContext(JNIEnv* env, jobject igcls, jobject context_jh)) {
1464 Handle context(THREAD, JNIHandles::resolve_non_null(context_jh));
1465 {
1466 // Walk all nmethods depending on this call site.
1467 MutexLocker mu1(Compile_lock, thread);
1468
1469 int marked = 0;
1470 {
1471 NoSafepointVerifier nsv;
1472 MutexLockerEx mu2(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1473 assert(safe_to_expunge(), "removal is not safe");
1474 DependencyContext deps = java_lang_invoke_MethodHandleNatives_CallSiteContext::vmdependencies(context());
1475 marked = deps.remove_all_dependents();
1476 }
1477 if (marked > 0) {
1478 // At least one nmethod has been marked for deoptimization
1479 VM_Deoptimize op;
1480 VMThread::execute(&op);
1481 }
1482 }
1483 }
1484 JVM_END
1485
1486 /**
1487 * Throws a java/lang/UnsupportedOperationException unconditionally.
1488 * This is required by the specification of MethodHandle.invoke if
1489 * invoked directly.
1490 */
1491 JVM_ENTRY(jobject, MH_invoke_UOE(JNIEnv* env, jobject mh, jobjectArray args)) {
1492 THROW_MSG_NULL(vmSymbols::java_lang_UnsupportedOperationException(), "MethodHandle.invoke cannot be invoked reflectively");
1493 return NULL;
1494 }
1495 JVM_END
1496
1497 /**
1498 * Throws a java/lang/UnsupportedOperationException unconditionally.
1499 * This is required by the specification of MethodHandle.invokeExact if
1500 * invoked directly.
1501 */
1502 JVM_ENTRY(jobject, MH_invokeExact_UOE(JNIEnv* env, jobject mh, jobjectArray args)) {
1503 THROW_MSG_NULL(vmSymbols::java_lang_UnsupportedOperationException(), "MethodHandle.invokeExact cannot be invoked reflectively");
1504 return NULL;
1505 }
1506 JVM_END
1507
1508 /// JVM_RegisterMethodHandleMethods
1509
1510 #undef CS // Solaris builds complain
1511
1512 #define LANG "Ljava/lang/"
1513 #define JLINV "Ljava/lang/invoke/"
1514
1515 #define OBJ LANG "Object;"
1516 #define CLS LANG "Class;"
1517 #define STRG LANG "String;"
1518 #define CS JLINV "CallSite;"
1519 #define MT JLINV "MethodType;"
1520 #define MH JLINV "MethodHandle;"
1521 #define MEM JLINV "MemberName;"
1522 #define CTX JLINV "MethodHandleNatives$CallSiteContext;"
1523
1524 #define CC (char*) /*cast a literal from (const char*)*/
1525 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1526
1527 // These are the native methods on java.lang.invoke.MethodHandleNatives.
1528 static JNINativeMethod MHN_methods[] = {
1529 {CC "init", CC "(" MEM "" OBJ ")V", FN_PTR(MHN_init_Mem)},
1530 {CC "expand", CC "(" MEM ")V", FN_PTR(MHN_expand_Mem)},
1531 {CC "resolve", CC "(" MEM "" CLS "Z)" MEM, FN_PTR(MHN_resolve_Mem)},
1532 // static native int getNamedCon(int which, Object[] name)
1533 {CC "getNamedCon", CC "(I[" OBJ ")I", FN_PTR(MHN_getNamedCon)},
1534 // static native int getMembers(Class<?> defc, String matchName, String matchSig,
1535 // int matchFlags, Class<?> caller, int skip, MemberName[] results);
1536 {CC "getMembers", CC "(" CLS "" STRG "" STRG "I" CLS "I[" MEM ")I", FN_PTR(MHN_getMembers)},
1537 {CC "objectFieldOffset", CC "(" MEM ")J", FN_PTR(MHN_objectFieldOffset)},
1538 {CC "setCallSiteTargetNormal", CC "(" CS "" MH ")V", FN_PTR(MHN_setCallSiteTargetNormal)},
1539 {CC "setCallSiteTargetVolatile", CC "(" CS "" MH ")V", FN_PTR(MHN_setCallSiteTargetVolatile)},
1540 {CC "copyOutBootstrapArguments", CC "(" CLS "[III[" OBJ "IZ" OBJ ")V", FN_PTR(MHN_copyOutBootstrapArguments)},
1541 {CC "clearCallSiteContext", CC "(" CTX ")V", FN_PTR(MHN_clearCallSiteContext)},
1542 {CC "staticFieldOffset", CC "(" MEM ")J", FN_PTR(MHN_staticFieldOffset)},
1543 {CC "staticFieldBase", CC "(" MEM ")" OBJ, FN_PTR(MHN_staticFieldBase)},
1544 {CC "getMemberVMInfo", CC "(" MEM ")" OBJ, FN_PTR(MHN_getMemberVMInfo)}
1545 };
1546
1547 static JNINativeMethod MH_methods[] = {
1548 // UnsupportedOperationException throwers
1549 {CC "invoke", CC "([" OBJ ")" OBJ, FN_PTR(MH_invoke_UOE)},
1550 {CC "invokeExact", CC "([" OBJ ")" OBJ, FN_PTR(MH_invokeExact_UOE)}
1551 };
1552
1553 /**
1554 * This one function is exported, used by NativeLookup.
1555 */
1556 JVM_ENTRY(void, JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass MHN_class)) {
1557 assert(!MethodHandles::enabled(), "must not be enabled");
1558 assert(SystemDictionary::MethodHandle_klass() != NULL, "should be present");
1559
1560 oop mirror = SystemDictionary::MethodHandle_klass()->java_mirror();
1561 jclass MH_class = (jclass) JNIHandles::make_local(env, mirror);
1562
1563 {
1564 ThreadToNativeFromVM ttnfv(thread);
1565
1566 int status = env->RegisterNatives(MHN_class, MHN_methods, sizeof(MHN_methods)/sizeof(JNINativeMethod));
1567 guarantee(status == JNI_OK && !env->ExceptionOccurred(),
1568 "register java.lang.invoke.MethodHandleNative natives");
1569
1570 status = env->RegisterNatives(MH_class, MH_methods, sizeof(MH_methods)/sizeof(JNINativeMethod));
1571 guarantee(status == JNI_OK && !env->ExceptionOccurred(),
1572 "register java.lang.invoke.MethodHandle natives");
1573 }
1574
1575 if (TraceInvokeDynamic) {
1576 tty->print_cr("MethodHandle support loaded (using LambdaForms)");
1577 }
1578
1579 MethodHandles::set_enabled(true);
1580 }
1581 JVM_END