1 /*
2 * Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "interpreter/interpreter.hpp"
28 #include "interpreter/oopMapCache.hpp"
29 #include "memory/allocation.inline.hpp"
30 #include "memory/oopFactory.hpp"
31 #include "prims/methodHandles.hpp"
32 #include "prims/methodHandleWalk.hpp"
33 #include "runtime/javaCalls.hpp"
34 #include "runtime/reflection.hpp"
35 #include "runtime/signature.hpp"
36 #include "runtime/stubRoutines.hpp"
37
38 /*
39 * JSR 292 reference implementation: method handles
40 */
41
42 bool MethodHandles::_enabled = false; // set true after successful native linkage
43
44 MethodHandleEntry* MethodHandles::_entries[MethodHandles::_EK_LIMIT] = {NULL};
45 const char* MethodHandles::_entry_names[_EK_LIMIT+1] = {
46 "raise_exception",
47 "invokestatic", // how a MH emulates invokestatic
48 "invokespecial", // ditto for the other invokes...
49 "invokevirtual",
50 "invokeinterface",
51 "bound_ref", // these are for BMH...
52 "bound_int",
53 "bound_long",
54 "bound_ref_direct", // (direct versions have a direct methodOop)
55 "bound_int_direct",
56 "bound_long_direct",
57
58 // starting at _adapter_mh_first:
59 "adapter_retype_only", // these are for AMH...
60 "adapter_retype_raw",
61 "adapter_check_cast",
62 "adapter_prim_to_prim",
63 "adapter_ref_to_prim",
64 "adapter_prim_to_ref",
65 "adapter_swap_args",
66 "adapter_rot_args",
67 "adapter_dup_args",
68 "adapter_drop_args",
69 "adapter_collect_args",
70 "adapter_spread_args",
71 "adapter_fold_args",
72 "adapter_unused_13",
73
74 // optimized adapter types:
75 "adapter_swap_args/1",
76 "adapter_swap_args/2",
77 "adapter_rot_args/1,up",
78 "adapter_rot_args/1,down",
79 "adapter_rot_args/2,up",
80 "adapter_rot_args/2,down",
81 "adapter_prim_to_prim/i2i",
82 "adapter_prim_to_prim/l2i",
83 "adapter_prim_to_prim/d2f",
84 "adapter_prim_to_prim/i2l",
85 "adapter_prim_to_prim/f2d",
86 "adapter_ref_to_prim/unboxi",
87 "adapter_ref_to_prim/unboxl",
88
89 // return value handlers for collect/filter/fold adapters:
90 "return/ref",
91 "return/int",
92 "return/long",
93 "return/float",
94 "return/double",
95 "return/void",
96 "return/S0/ref",
97 "return/S1/ref",
98 "return/S2/ref",
99 "return/S3/ref",
100 "return/S4/ref",
101 "return/S5/ref",
102 "return/any",
103
104 // spreading (array length cases 0, 1, ...)
105 "adapter_spread/0",
106 "adapter_spread/1/ref",
107 "adapter_spread/2/ref",
108 "adapter_spread/3/ref",
109 "adapter_spread/4/ref",
110 "adapter_spread/5/ref",
111 "adapter_spread/ref",
112 "adapter_spread/byte",
113 "adapter_spread/char",
114 "adapter_spread/short",
115 "adapter_spread/int",
116 "adapter_spread/long",
117 "adapter_spread/float",
118 "adapter_spread/double",
119
120 // blocking filter/collect conversions:
121 "adapter_collect/ref",
122 "adapter_collect/int",
123 "adapter_collect/long",
124 "adapter_collect/float",
125 "adapter_collect/double",
126 "adapter_collect/void",
127 "adapter_collect/0/ref",
128 "adapter_collect/1/ref",
129 "adapter_collect/2/ref",
130 "adapter_collect/3/ref",
131 "adapter_collect/4/ref",
132 "adapter_collect/5/ref",
133 "adapter_filter/S0/ref",
134 "adapter_filter/S1/ref",
135 "adapter_filter/S2/ref",
136 "adapter_filter/S3/ref",
137 "adapter_filter/S4/ref",
138 "adapter_filter/S5/ref",
139 "adapter_collect/2/S0/ref",
140 "adapter_collect/2/S1/ref",
141 "adapter_collect/2/S2/ref",
142 "adapter_collect/2/S3/ref",
143 "adapter_collect/2/S4/ref",
144 "adapter_collect/2/S5/ref",
145
146 // blocking fold conversions:
147 "adapter_fold/ref",
148 "adapter_fold/int",
149 "adapter_fold/long",
150 "adapter_fold/float",
151 "adapter_fold/double",
152 "adapter_fold/void",
153 "adapter_fold/1/ref",
154 "adapter_fold/2/ref",
155 "adapter_fold/3/ref",
156 "adapter_fold/4/ref",
157 "adapter_fold/5/ref",
158
159 NULL
160 };
161
162 // Adapters.
163 MethodHandlesAdapterBlob* MethodHandles::_adapter_code = NULL;
164
165 jobject MethodHandles::_raise_exception_method;
166
167 address MethodHandles::_adapter_return_handlers[CONV_TYPE_MASK+1];
168
169 #ifdef ASSERT
170 bool MethodHandles::spot_check_entry_names() {
171 assert(!strcmp(entry_name(_invokestatic_mh), "invokestatic"), "");
172 assert(!strcmp(entry_name(_bound_ref_mh), "bound_ref"), "");
173 assert(!strcmp(entry_name(_adapter_retype_only), "adapter_retype_only"), "");
174 assert(!strcmp(entry_name(_adapter_fold_args), "adapter_fold_args"), "");
175 assert(!strcmp(entry_name(_adapter_opt_unboxi), "adapter_ref_to_prim/unboxi"), "");
176 assert(!strcmp(entry_name(_adapter_opt_spread_char), "adapter_spread/char"), "");
177 assert(!strcmp(entry_name(_adapter_opt_spread_double), "adapter_spread/double"), "");
178 assert(!strcmp(entry_name(_adapter_opt_collect_int), "adapter_collect/int"), "");
179 assert(!strcmp(entry_name(_adapter_opt_collect_0_ref), "adapter_collect/0/ref"), "");
180 assert(!strcmp(entry_name(_adapter_opt_collect_2_S3_ref), "adapter_collect/2/S3/ref"), "");
181 assert(!strcmp(entry_name(_adapter_opt_filter_S5_ref), "adapter_filter/S5/ref"), "");
182 assert(!strcmp(entry_name(_adapter_opt_fold_3_ref), "adapter_fold/3/ref"), "");
183 assert(!strcmp(entry_name(_adapter_opt_fold_void), "adapter_fold/void"), "");
184 return true;
185 }
186 #endif
187
188
189 //------------------------------------------------------------------------------
190 // MethodHandles::generate_adapters
191 //
192 void MethodHandles::generate_adapters() {
193 #ifdef TARGET_ARCH_NYI_6939861
194 if (FLAG_IS_DEFAULT(UseRicochetFrames)) UseRicochetFrames = false;
195 #endif
196 if (!EnableInvokeDynamic || SystemDictionary::MethodHandle_klass() == NULL) return;
197
198 assert(_adapter_code == NULL, "generate only once");
199
200 ResourceMark rm;
201 TraceTime timer("MethodHandles adapters generation", TraceStartupTime);
202 _adapter_code = MethodHandlesAdapterBlob::create(adapter_code_size);
203 if (_adapter_code == NULL)
204 vm_exit_out_of_memory(adapter_code_size, "CodeCache: no room for MethodHandles adapters");
205 CodeBuffer code(_adapter_code);
206 MethodHandlesAdapterGenerator g(&code);
207 g.generate();
208
209 // Transfer code comments
210 _adapter_code->set_comments(code.comments());
211 }
212
213 //------------------------------------------------------------------------------
214 // MethodHandlesAdapterGenerator::generate
215 //
216 void MethodHandlesAdapterGenerator::generate() {
217 // Generate generic method handle adapters.
218 for (MethodHandles::EntryKind ek = MethodHandles::_EK_FIRST;
219 ek < MethodHandles::_EK_LIMIT;
220 ek = MethodHandles::EntryKind(1 + (int)ek)) {
221 if (MethodHandles::ek_supported(ek)) {
222 StubCodeMark mark(this, "MethodHandle", MethodHandles::entry_name(ek));
223 MethodHandles::generate_method_handle_stub(_masm, ek);
224 }
225 }
226 }
227
228
229 #ifdef TARGET_ARCH_NYI_6939861
230 // these defs belong in methodHandles_<arch>.cpp
231 frame MethodHandles::ricochet_frame_sender(const frame& fr, RegisterMap *map) {
232 ShouldNotCallThis();
233 return fr;
234 }
235 void MethodHandles::ricochet_frame_oops_do(const frame& fr, OopClosure* f, const RegisterMap* reg_map) {
236 ShouldNotCallThis();
237 }
238 #endif //TARGET_ARCH_NYI_6939861
239
240
241 //------------------------------------------------------------------------------
242 // MethodHandles::ek_supported
243 //
244 bool MethodHandles::ek_supported(MethodHandles::EntryKind ek) {
245 MethodHandles::EntryKind ek_orig = MethodHandles::ek_original_kind(ek);
246 switch (ek_orig) {
247 case _adapter_unused_13:
248 return false; // not defined yet
249 case _adapter_prim_to_ref:
250 return UseRicochetFrames && conv_op_supported(java_lang_invoke_AdapterMethodHandle::OP_PRIM_TO_REF);
251 case _adapter_collect_args:
252 return UseRicochetFrames && conv_op_supported(java_lang_invoke_AdapterMethodHandle::OP_COLLECT_ARGS);
253 case _adapter_fold_args:
254 return UseRicochetFrames && conv_op_supported(java_lang_invoke_AdapterMethodHandle::OP_FOLD_ARGS);
255 case _adapter_opt_return_any:
256 return UseRicochetFrames;
257 #ifdef TARGET_ARCH_NYI_6939861
258 // ports before 6939861 supported only three kinds of spread ops
259 case _adapter_spread_args:
260 // restrict spreads to three kinds:
261 switch (ek) {
262 case _adapter_opt_spread_0:
263 case _adapter_opt_spread_1:
264 case _adapter_opt_spread_more:
265 break;
266 default:
267 return false;
268 break;
269 }
270 break;
271 #endif //TARGET_ARCH_NYI_6939861
272 }
273 return true;
274 }
275
276
277 void MethodHandles::set_enabled(bool z) {
278 if (_enabled != z) {
279 guarantee(z && EnableInvokeDynamic, "can only enable once, and only if -XX:+EnableInvokeDynamic");
280 _enabled = z;
281 }
282 }
283
284 // Note: A method which does not have a TRAPS argument cannot block in the GC
285 // or throw exceptions. Such methods are used in this file to do something quick
286 // and local, like parse a data structure. For speed, such methods work on plain
287 // oops, not handles. Trapping methods uniformly operate on handles.
288
289 methodHandle MethodHandles::decode_vmtarget(oop vmtarget, int vmindex, oop mtype,
290 KlassHandle& receiver_limit_result, int& decode_flags_result) {
291 if (vmtarget == NULL) return methodHandle();
292 assert(methodOopDesc::nonvirtual_vtable_index < 0, "encoding");
293 if (vmindex < 0) {
294 // this DMH performs no dispatch; it is directly bound to a methodOop
295 // A MemberName may either be directly bound to a methodOop,
296 // or it may use the klass/index form; both forms mean the same thing.
297 methodOop m = decode_methodOop(methodOop(vmtarget), decode_flags_result);
298 if ((decode_flags_result & _dmf_has_receiver) != 0
299 && java_lang_invoke_MethodType::is_instance(mtype)) {
300 // Extract receiver type restriction from mtype.ptypes[0].
301 objArrayOop ptypes = java_lang_invoke_MethodType::ptypes(mtype);
302 oop ptype0 = (ptypes == NULL || ptypes->length() < 1) ? oop(NULL) : ptypes->obj_at(0);
303 if (java_lang_Class::is_instance(ptype0))
304 receiver_limit_result = java_lang_Class::as_klassOop(ptype0);
305 }
306 if (vmindex == methodOopDesc::nonvirtual_vtable_index) {
307 // this DMH can be an "invokespecial" version
308 decode_flags_result &= ~_dmf_does_dispatch;
309 } else {
310 assert(vmindex == methodOopDesc::invalid_vtable_index, "random vmindex?");
311 }
312 return m;
313 } else {
314 assert(vmtarget->is_klass(), "must be class or interface");
315 decode_flags_result |= MethodHandles::_dmf_does_dispatch;
316 decode_flags_result |= MethodHandles::_dmf_has_receiver;
317 receiver_limit_result = (klassOop)vmtarget;
318 Klass* tk = Klass::cast((klassOop)vmtarget);
319 if (tk->is_interface()) {
320 // an itable linkage is <interface, itable index>
321 decode_flags_result |= MethodHandles::_dmf_from_interface;
322 return klassItable::method_for_itable_index((klassOop)vmtarget, vmindex);
323 } else {
324 if (!tk->oop_is_instance())
325 tk = instanceKlass::cast(SystemDictionary::Object_klass());
326 return ((instanceKlass*)tk)->method_at_vtable(vmindex);
327 }
328 }
329 }
330
331 // MemberName and DirectMethodHandle have the same linkage to the JVM internals.
332 // (MemberName is the non-operational name used for queries and setup.)
333
334 methodHandle MethodHandles::decode_DirectMethodHandle(oop mh, KlassHandle& receiver_limit_result, int& decode_flags_result) {
335 oop vmtarget = java_lang_invoke_DirectMethodHandle::vmtarget(mh);
336 int vmindex = java_lang_invoke_DirectMethodHandle::vmindex(mh);
337 oop mtype = java_lang_invoke_DirectMethodHandle::type(mh);
338 return decode_vmtarget(vmtarget, vmindex, mtype, receiver_limit_result, decode_flags_result);
339 }
340
341 methodHandle MethodHandles::decode_BoundMethodHandle(oop mh, KlassHandle& receiver_limit_result, int& decode_flags_result) {
342 assert(java_lang_invoke_BoundMethodHandle::is_instance(mh), "");
343 assert(mh->klass() != SystemDictionary::AdapterMethodHandle_klass(), "");
344 for (oop bmh = mh;;) {
345 // Bound MHs can be stacked to bind several arguments.
346 oop target = java_lang_invoke_MethodHandle::vmtarget(bmh);
347 if (target == NULL) return methodHandle();
348 decode_flags_result |= MethodHandles::_dmf_binds_argument;
349 klassOop tk = target->klass();
350 if (tk == SystemDictionary::BoundMethodHandle_klass()) {
351 bmh = target;
352 continue;
353 } else {
354 if (java_lang_invoke_MethodHandle::is_subclass(tk)) {
355 //assert(tk == SystemDictionary::DirectMethodHandle_klass(), "end of BMH chain must be DMH");
356 return decode_MethodHandle(target, receiver_limit_result, decode_flags_result);
357 } else {
358 // Optimized case: binding a receiver to a non-dispatched DMH
359 // short-circuits directly to the methodOop.
360 // (It might be another argument besides a receiver also.)
361 assert(target->is_method(), "must be a simple method");
362 decode_flags_result |= MethodHandles::_dmf_binds_method;
363 methodOop m = (methodOop) target;
364 if (!m->is_static())
365 decode_flags_result |= MethodHandles::_dmf_has_receiver;
366 return m;
367 }
368 }
369 }
370 }
371
372 methodHandle MethodHandles::decode_AdapterMethodHandle(oop mh, KlassHandle& receiver_limit_result, int& decode_flags_result) {
373 assert(mh->klass() == SystemDictionary::AdapterMethodHandle_klass(), "");
374 for (oop amh = mh;;) {
375 // Adapter MHs can be stacked to convert several arguments.
376 int conv_op = adapter_conversion_op(java_lang_invoke_AdapterMethodHandle::conversion(amh));
377 decode_flags_result |= (_dmf_adapter_lsb << conv_op) & _DMF_ADAPTER_MASK;
378 oop target = java_lang_invoke_MethodHandle::vmtarget(amh);
379 if (target == NULL) return methodHandle();
380 klassOop tk = target->klass();
381 if (tk == SystemDictionary::AdapterMethodHandle_klass()) {
382 amh = target;
383 continue;
384 } else {
385 // must be a BMH (which will bind some more arguments) or a DMH (for the final call)
386 return MethodHandles::decode_MethodHandle(target, receiver_limit_result, decode_flags_result);
387 }
388 }
389 }
390
391 methodHandle MethodHandles::decode_MethodHandle(oop mh, KlassHandle& receiver_limit_result, int& decode_flags_result) {
392 if (mh == NULL) return methodHandle();
393 klassOop mhk = mh->klass();
394 assert(java_lang_invoke_MethodHandle::is_subclass(mhk), "must be a MethodHandle");
395 if (mhk == SystemDictionary::DirectMethodHandle_klass()) {
396 return decode_DirectMethodHandle(mh, receiver_limit_result, decode_flags_result);
397 } else if (mhk == SystemDictionary::BoundMethodHandle_klass()) {
398 return decode_BoundMethodHandle(mh, receiver_limit_result, decode_flags_result);
399 } else if (mhk == SystemDictionary::AdapterMethodHandle_klass()) {
400 return decode_AdapterMethodHandle(mh, receiver_limit_result, decode_flags_result);
401 } else if (java_lang_invoke_BoundMethodHandle::is_subclass(mhk)) {
402 // could be a JavaMethodHandle (but not an adapter MH)
403 return decode_BoundMethodHandle(mh, receiver_limit_result, decode_flags_result);
404 } else {
405 assert(false, "cannot parse this MH");
406 return methodHandle(); // random MH?
407 }
408 }
409
410 methodOop MethodHandles::decode_methodOop(methodOop m, int& decode_flags_result) {
411 assert(m->is_method(), "");
412 if (m->is_static()) {
413 // check that signature begins '(L' or '([' (not '(I', '()', etc.)
414 Symbol* sig = m->signature();
415 BasicType recv_bt = char2type(sig->byte_at(1));
416 // Note: recv_bt might be T_ILLEGAL if byte_at(2) is ')'
417 assert(sig->byte_at(0) == '(', "must be method sig");
418 // if (recv_bt == T_OBJECT || recv_bt == T_ARRAY)
419 // decode_flags_result |= _dmf_has_receiver;
420 } else {
421 // non-static method
422 decode_flags_result |= _dmf_has_receiver;
423 if (!m->can_be_statically_bound() && !m->is_initializer()) {
424 decode_flags_result |= _dmf_does_dispatch;
425 if (Klass::cast(m->method_holder())->is_interface())
426 decode_flags_result |= _dmf_from_interface;
427 }
428 }
429 return m;
430 }
431
432
433 // A trusted party is handing us a cookie to determine a method.
434 // Let's boil it down to the method oop they really want.
435 methodHandle MethodHandles::decode_method(oop x, KlassHandle& receiver_limit_result, int& decode_flags_result) {
436 decode_flags_result = 0;
437 receiver_limit_result = KlassHandle();
438 klassOop xk = x->klass();
439 if (xk == Universe::methodKlassObj()) {
440 return decode_methodOop((methodOop) x, decode_flags_result);
441 } else if (xk == SystemDictionary::MemberName_klass()) {
442 // Note: This only works if the MemberName has already been resolved.
443 return decode_MemberName(x, receiver_limit_result, decode_flags_result);
444 } else if (java_lang_invoke_MethodHandle::is_subclass(xk)) {
445 return decode_MethodHandle(x, receiver_limit_result, decode_flags_result);
446 } else if (xk == SystemDictionary::reflect_Method_klass()) {
447 oop clazz = java_lang_reflect_Method::clazz(x);
448 int slot = java_lang_reflect_Method::slot(x);
449 klassOop k = java_lang_Class::as_klassOop(clazz);
450 if (k != NULL && Klass::cast(k)->oop_is_instance())
451 return decode_methodOop(instanceKlass::cast(k)->method_with_idnum(slot),
452 decode_flags_result);
453 } else if (xk == SystemDictionary::reflect_Constructor_klass()) {
454 oop clazz = java_lang_reflect_Constructor::clazz(x);
455 int slot = java_lang_reflect_Constructor::slot(x);
456 klassOop k = java_lang_Class::as_klassOop(clazz);
457 if (k != NULL && Klass::cast(k)->oop_is_instance())
458 return decode_methodOop(instanceKlass::cast(k)->method_with_idnum(slot),
459 decode_flags_result);
460 } else {
461 // unrecognized object
462 assert(!x->is_method(), "already checked");
463 assert(!java_lang_invoke_MemberName::is_instance(x), "already checked");
464 }
465 return methodHandle();
466 }
467
468
469 int MethodHandles::decode_MethodHandle_stack_pushes(oop mh) {
470 if (mh->klass() == SystemDictionary::DirectMethodHandle_klass())
471 return 0; // no push/pop
472 int this_vmslots = java_lang_invoke_MethodHandle::vmslots(mh);
473 int last_vmslots = 0;
474 oop last_mh = mh;
475 for (;;) {
476 oop target = java_lang_invoke_MethodHandle::vmtarget(last_mh);
477 if (target->klass() == SystemDictionary::DirectMethodHandle_klass()) {
478 last_vmslots = java_lang_invoke_MethodHandle::vmslots(target);
479 break;
480 } else if (!java_lang_invoke_MethodHandle::is_instance(target)) {
481 // might be klass or method
482 assert(target->is_method(), "must get here with a direct ref to method");
483 last_vmslots = methodOop(target)->size_of_parameters();
484 break;
485 }
486 last_mh = target;
487 }
488 // If I am called with fewer VM slots than my ultimate callee,
489 // it must be that I push the additionally needed slots.
490 // Likewise if am called with more VM slots, I will pop them.
491 return (last_vmslots - this_vmslots);
492 }
493
494
495 // MemberName support
496
497 // import java_lang_invoke_MemberName.*
498 enum {
499 IS_METHOD = java_lang_invoke_MemberName::MN_IS_METHOD,
500 IS_CONSTRUCTOR = java_lang_invoke_MemberName::MN_IS_CONSTRUCTOR,
501 IS_FIELD = java_lang_invoke_MemberName::MN_IS_FIELD,
502 IS_TYPE = java_lang_invoke_MemberName::MN_IS_TYPE,
503 SEARCH_SUPERCLASSES = java_lang_invoke_MemberName::MN_SEARCH_SUPERCLASSES,
504 SEARCH_INTERFACES = java_lang_invoke_MemberName::MN_SEARCH_INTERFACES,
505 ALL_KINDS = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE,
506 VM_INDEX_UNINITIALIZED = java_lang_invoke_MemberName::VM_INDEX_UNINITIALIZED
507 };
508
509 Handle MethodHandles::new_MemberName(TRAPS) {
510 Handle empty;
511 instanceKlassHandle k(THREAD, SystemDictionary::MemberName_klass());
512 if (!k->is_initialized()) k->initialize(CHECK_(empty));
513 return Handle(THREAD, k->allocate_instance(THREAD));
514 }
515
516 void MethodHandles::init_MemberName(oop mname_oop, oop target_oop) {
517 if (target_oop->klass() == SystemDictionary::reflect_Field_klass()) {
518 oop clazz = java_lang_reflect_Field::clazz(target_oop); // fd.field_holder()
519 int slot = java_lang_reflect_Field::slot(target_oop); // fd.index()
520 int mods = java_lang_reflect_Field::modifiers(target_oop);
521 klassOop k = java_lang_Class::as_klassOop(clazz);
522 int offset = instanceKlass::cast(k)->offset_from_fields(slot);
523 init_MemberName(mname_oop, k, accessFlags_from(mods), offset);
524 } else {
525 KlassHandle receiver_limit; int decode_flags = 0;
526 methodHandle m = MethodHandles::decode_method(target_oop, receiver_limit, decode_flags);
527 bool do_dispatch = ((decode_flags & MethodHandles::_dmf_does_dispatch) != 0);
528 init_MemberName(mname_oop, m(), do_dispatch);
529 }
530 }
531
532 void MethodHandles::init_MemberName(oop mname_oop, methodOop m, bool do_dispatch) {
533 int flags = ((m->is_initializer() ? IS_CONSTRUCTOR : IS_METHOD)
534 | (jushort)( m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS ));
535 oop vmtarget = m;
536 int vmindex = methodOopDesc::invalid_vtable_index; // implies no info yet
537 if (!do_dispatch || (flags & IS_CONSTRUCTOR) || m->can_be_statically_bound())
538 vmindex = methodOopDesc::nonvirtual_vtable_index; // implies never any dispatch
539 assert(vmindex != VM_INDEX_UNINITIALIZED, "Java sentinel value");
540 java_lang_invoke_MemberName::set_vmtarget(mname_oop, vmtarget);
541 java_lang_invoke_MemberName::set_vmindex(mname_oop, vmindex);
542 java_lang_invoke_MemberName::set_flags(mname_oop, flags);
543 java_lang_invoke_MemberName::set_clazz(mname_oop, Klass::cast(m->method_holder())->java_mirror());
544 }
545
546 void MethodHandles::init_MemberName(oop mname_oop, klassOop field_holder, AccessFlags mods, int offset) {
547 int flags = (IS_FIELD | (jushort)( mods.as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS ));
548 oop vmtarget = field_holder;
549 int vmindex = offset; // determines the field uniquely when combined with static bit
550 assert(vmindex != VM_INDEX_UNINITIALIZED, "bad alias on vmindex");
551 java_lang_invoke_MemberName::set_vmtarget(mname_oop, vmtarget);
552 java_lang_invoke_MemberName::set_vmindex(mname_oop, vmindex);
553 java_lang_invoke_MemberName::set_flags(mname_oop, flags);
554 java_lang_invoke_MemberName::set_clazz(mname_oop, Klass::cast(field_holder)->java_mirror());
555 }
556
557
558 methodHandle MethodHandles::decode_MemberName(oop mname, KlassHandle& receiver_limit_result, int& decode_flags_result) {
559 methodHandle empty;
560 int flags = java_lang_invoke_MemberName::flags(mname);
561 if ((flags & (IS_METHOD | IS_CONSTRUCTOR)) == 0) return empty; // not invocable
562 oop vmtarget = java_lang_invoke_MemberName::vmtarget(mname);
563 int vmindex = java_lang_invoke_MemberName::vmindex(mname);
564 if (vmindex == VM_INDEX_UNINITIALIZED) return empty; // not resolved
565 methodHandle m = decode_vmtarget(vmtarget, vmindex, NULL, receiver_limit_result, decode_flags_result);
566 oop clazz = java_lang_invoke_MemberName::clazz(mname);
567 if (clazz != NULL && java_lang_Class::is_instance(clazz)) {
568 klassOop klass = java_lang_Class::as_klassOop(clazz);
569 if (klass != NULL) receiver_limit_result = klass;
570 }
571 return m;
572 }
573
574 // convert the external string or reflective type to an internal signature
575 Symbol* MethodHandles::convert_to_signature(oop type_str, bool polymorphic, TRAPS) {
576 if (java_lang_invoke_MethodType::is_instance(type_str)) {
577 return java_lang_invoke_MethodType::as_signature(type_str, polymorphic, CHECK_NULL);
578 } else if (java_lang_Class::is_instance(type_str)) {
579 return java_lang_Class::as_signature(type_str, false, CHECK_NULL);
580 } else if (java_lang_String::is_instance(type_str)) {
581 if (polymorphic) {
582 return java_lang_String::as_symbol(type_str, CHECK_NULL);
583 } else {
584 return java_lang_String::as_symbol_or_null(type_str);
585 }
586 } else {
587 THROW_MSG_(vmSymbols::java_lang_InternalError(), "unrecognized type", NULL);
588 }
589 }
590
591 // An unresolved member name is a mere symbolic reference.
592 // Resolving it plants a vmtarget/vmindex in it,
593 // which refers dirctly to JVM internals.
594 void MethodHandles::resolve_MemberName(Handle mname, TRAPS) {
595 assert(java_lang_invoke_MemberName::is_instance(mname()), "");
596 #ifdef ASSERT
597 // If this assert throws, renegotiate the sentinel value used by the Java code,
598 // so that it is distinct from any valid vtable index value, and any special
599 // values defined in methodOopDesc::VtableIndexFlag.
600 // The point of the slop is to give the Java code and the JVM some room
601 // to independently specify sentinel values.
602 const int sentinel_slop = 10;
603 const int sentinel_limit = methodOopDesc::highest_unused_vtable_index_value - sentinel_slop;
604 assert(VM_INDEX_UNINITIALIZED < sentinel_limit, "Java sentinel != JVM sentinels");
605 #endif
606 if (java_lang_invoke_MemberName::vmindex(mname()) != VM_INDEX_UNINITIALIZED)
607 return; // already resolved
608 Handle defc_oop(THREAD, java_lang_invoke_MemberName::clazz(mname()));
609 Handle name_str(THREAD, java_lang_invoke_MemberName::name( mname()));
610 Handle type_str(THREAD, java_lang_invoke_MemberName::type( mname()));
611 int flags = java_lang_invoke_MemberName::flags(mname());
612
613 if (defc_oop.is_null() || name_str.is_null() || type_str.is_null()) {
614 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to resolve");
615 }
616
617 instanceKlassHandle defc;
618 {
619 klassOop defc_klassOop = java_lang_Class::as_klassOop(defc_oop());
620 if (defc_klassOop == NULL) return; // a primitive; no resolution possible
621 if (!Klass::cast(defc_klassOop)->oop_is_instance()) {
622 if (!Klass::cast(defc_klassOop)->oop_is_array()) return;
623 defc_klassOop = SystemDictionary::Object_klass();
624 }
625 defc = instanceKlassHandle(THREAD, defc_klassOop);
626 }
627 if (defc.is_null()) {
628 THROW_MSG(vmSymbols::java_lang_InternalError(), "primitive class");
629 }
630 defc->link_class(CHECK); // possible safepoint
631
632 // convert the external string name to an internal symbol
633 TempNewSymbol name = java_lang_String::as_symbol_or_null(name_str());
634 if (name == NULL) return; // no such name
635
636 Handle polymorphic_method_type;
637 bool polymorphic_signature = false;
638 if ((flags & ALL_KINDS) == IS_METHOD &&
639 (defc() == SystemDictionary::MethodHandle_klass() &&
640 methodOopDesc::is_method_handle_invoke_name(name))) {
641 polymorphic_signature = true;
642 }
643
644 // convert the external string or reflective type to an internal signature
645 TempNewSymbol type = convert_to_signature(type_str(), polymorphic_signature, CHECK);
646 if (java_lang_invoke_MethodType::is_instance(type_str()) && polymorphic_signature) {
647 polymorphic_method_type = type_str; // preserve exactly
648 }
649 if (type == NULL) return; // no such signature exists in the VM
650
651 // Time to do the lookup.
652 switch (flags & ALL_KINDS) {
653 case IS_METHOD:
654 {
655 CallInfo result;
656 {
657 EXCEPTION_MARK;
658 if ((flags & JVM_ACC_STATIC) != 0) {
659 LinkResolver::resolve_static_call(result,
660 defc, name, type, KlassHandle(), false, false, THREAD);
661 } else if (defc->is_interface()) {
662 LinkResolver::resolve_interface_call(result, Handle(), defc,
663 defc, name, type, KlassHandle(), false, false, THREAD);
664 } else {
665 LinkResolver::resolve_virtual_call(result, Handle(), defc,
666 defc, name, type, KlassHandle(), false, false, THREAD);
667 }
668 if (HAS_PENDING_EXCEPTION) {
669 CLEAR_PENDING_EXCEPTION;
670 break; // go to second chance
671 }
672 }
673 methodHandle m = result.resolved_method();
674 oop vmtarget = NULL;
675 int vmindex = methodOopDesc::nonvirtual_vtable_index;
676 if (defc->is_interface()) {
677 vmindex = klassItable::compute_itable_index(m());
678 assert(vmindex >= 0, "");
679 } else if (result.has_vtable_index()) {
680 vmindex = result.vtable_index();
681 assert(vmindex >= 0, "");
682 }
683 assert(vmindex != VM_INDEX_UNINITIALIZED, "");
684 if (vmindex < 0) {
685 assert(result.is_statically_bound(), "");
686 vmtarget = m();
687 } else {
688 vmtarget = result.resolved_klass()->as_klassOop();
689 }
690 int mods = (m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS);
691 java_lang_invoke_MemberName::set_vmtarget(mname(), vmtarget);
692 java_lang_invoke_MemberName::set_vmindex(mname(), vmindex);
693 java_lang_invoke_MemberName::set_modifiers(mname(), mods);
694 DEBUG_ONLY(KlassHandle junk1; int junk2);
695 assert(decode_MemberName(mname(), junk1, junk2) == result.resolved_method(),
696 "properly stored for later decoding");
697 return;
698 }
699 case IS_CONSTRUCTOR:
700 {
701 CallInfo result;
702 {
703 EXCEPTION_MARK;
704 if (name == vmSymbols::object_initializer_name()) {
705 LinkResolver::resolve_special_call(result,
706 defc, name, type, KlassHandle(), false, THREAD);
707 } else {
708 break; // will throw after end of switch
709 }
710 if (HAS_PENDING_EXCEPTION) {
711 CLEAR_PENDING_EXCEPTION;
712 return;
713 }
714 }
715 assert(result.is_statically_bound(), "");
716 methodHandle m = result.resolved_method();
717 oop vmtarget = m();
718 int vmindex = methodOopDesc::nonvirtual_vtable_index;
719 int mods = (m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS);
720 java_lang_invoke_MemberName::set_vmtarget(mname(), vmtarget);
721 java_lang_invoke_MemberName::set_vmindex(mname(), vmindex);
722 java_lang_invoke_MemberName::set_modifiers(mname(), mods);
723 DEBUG_ONLY(KlassHandle junk1; int junk2);
724 assert(decode_MemberName(mname(), junk1, junk2) == result.resolved_method(),
725 "properly stored for later decoding");
726 return;
727 }
728 case IS_FIELD:
729 {
730 // This is taken from LinkResolver::resolve_field, sans access checks.
731 fieldDescriptor fd; // find_field initializes fd if found
732 KlassHandle sel_klass(THREAD, instanceKlass::cast(defc())->find_field(name, type, &fd));
733 // check if field exists; i.e., if a klass containing the field def has been selected
734 if (sel_klass.is_null()) return;
735 oop vmtarget = sel_klass->as_klassOop();
736 int vmindex = fd.offset();
737 int mods = (fd.access_flags().as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS);
738 if (vmindex == VM_INDEX_UNINITIALIZED) break; // should not happen
739 java_lang_invoke_MemberName::set_vmtarget(mname(), vmtarget);
740 java_lang_invoke_MemberName::set_vmindex(mname(), vmindex);
741 java_lang_invoke_MemberName::set_modifiers(mname(), mods);
742 return;
743 }
744 default:
745 THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
746 }
747
748 // Second chance.
749 if (polymorphic_method_type.not_null()) {
750 // Look on a non-null class loader.
751 Handle cur_class_loader;
752 const int nptypes = java_lang_invoke_MethodType::ptype_count(polymorphic_method_type());
753 for (int i = 0; i <= nptypes; i++) {
754 oop type_mirror;
755 if (i < nptypes) type_mirror = java_lang_invoke_MethodType::ptype(polymorphic_method_type(), i);
756 else type_mirror = java_lang_invoke_MethodType::rtype(polymorphic_method_type());
757 klassOop example_type = java_lang_Class::as_klassOop(type_mirror);
758 if (example_type == NULL) continue;
759 oop class_loader = Klass::cast(example_type)->class_loader();
760 if (class_loader == NULL || class_loader == cur_class_loader()) continue;
761 cur_class_loader = Handle(THREAD, class_loader);
762 methodOop m = SystemDictionary::find_method_handle_invoke(name,
763 type,
764 KlassHandle(THREAD, example_type),
765 THREAD);
766 if (HAS_PENDING_EXCEPTION) {
767 CLEAR_PENDING_EXCEPTION;
768 m = NULL;
769 // try again with a different class loader...
770 }
771 if (m != NULL) {
772 int mods = (m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS);
773 java_lang_invoke_MemberName::set_vmtarget(mname(), m);
774 java_lang_invoke_MemberName::set_vmindex(mname(), m->vtable_index());
775 java_lang_invoke_MemberName::set_modifiers(mname(), mods);
776 return;
777 }
778 }
779 }
780 }
781
782 // Conversely, a member name which is only initialized from JVM internals
783 // may have null defc, name, and type fields.
784 // Resolving it plants a vmtarget/vmindex in it,
785 // which refers directly to JVM internals.
786 void MethodHandles::expand_MemberName(Handle mname, int suppress, TRAPS) {
787 assert(java_lang_invoke_MemberName::is_instance(mname()), "");
788 oop vmtarget = java_lang_invoke_MemberName::vmtarget(mname());
789 int vmindex = java_lang_invoke_MemberName::vmindex(mname());
790 if (vmtarget == NULL || vmindex == VM_INDEX_UNINITIALIZED) {
791 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nothing to expand");
792 }
793
794 bool have_defc = (java_lang_invoke_MemberName::clazz(mname()) != NULL);
795 bool have_name = (java_lang_invoke_MemberName::name(mname()) != NULL);
796 bool have_type = (java_lang_invoke_MemberName::type(mname()) != NULL);
797 int flags = java_lang_invoke_MemberName::flags(mname());
798
799 if (suppress != 0) {
800 if (suppress & _suppress_defc) have_defc = true;
801 if (suppress & _suppress_name) have_name = true;
802 if (suppress & _suppress_type) have_type = true;
803 }
804
805 if (have_defc && have_name && have_type) return; // nothing needed
806
807 switch (flags & ALL_KINDS) {
808 case IS_METHOD:
809 case IS_CONSTRUCTOR:
810 {
811 KlassHandle receiver_limit; int decode_flags = 0;
812 methodHandle m = decode_vmtarget(vmtarget, vmindex, NULL, receiver_limit, decode_flags);
813 if (m.is_null()) break;
814 if (!have_defc) {
815 klassOop defc = m->method_holder();
816 if (receiver_limit.not_null() && receiver_limit() != defc
817 && Klass::cast(receiver_limit())->is_subtype_of(defc))
818 defc = receiver_limit();
819 java_lang_invoke_MemberName::set_clazz(mname(), Klass::cast(defc)->java_mirror());
820 }
821 if (!have_name) {
822 //not java_lang_String::create_from_symbol; let's intern member names
823 Handle name = StringTable::intern(m->name(), CHECK);
824 java_lang_invoke_MemberName::set_name(mname(), name());
825 }
826 if (!have_type) {
827 Handle type = java_lang_String::create_from_symbol(m->signature(), CHECK);
828 java_lang_invoke_MemberName::set_type(mname(), type());
829 }
830 return;
831 }
832 case IS_FIELD:
833 {
834 // This is taken from LinkResolver::resolve_field, sans access checks.
835 if (!vmtarget->is_klass()) break;
836 if (!Klass::cast((klassOop) vmtarget)->oop_is_instance()) break;
837 instanceKlassHandle defc(THREAD, (klassOop) vmtarget);
838 bool is_static = ((flags & JVM_ACC_STATIC) != 0);
839 fieldDescriptor fd; // find_field initializes fd if found
840 if (!defc->find_field_from_offset(vmindex, is_static, &fd))
841 break; // cannot expand
842 if (!have_defc) {
843 java_lang_invoke_MemberName::set_clazz(mname(), defc->java_mirror());
844 }
845 if (!have_name) {
846 //not java_lang_String::create_from_symbol; let's intern member names
847 Handle name = StringTable::intern(fd.name(), CHECK);
848 java_lang_invoke_MemberName::set_name(mname(), name());
849 }
850 if (!have_type) {
851 Handle type = java_lang_String::create_from_symbol(fd.signature(), CHECK);
852 java_lang_invoke_MemberName::set_type(mname(), type());
853 }
854 return;
855 }
856 }
857 THROW_MSG(vmSymbols::java_lang_InternalError(), "unrecognized MemberName format");
858 }
859
860 int MethodHandles::find_MemberNames(klassOop k,
861 Symbol* name, Symbol* sig,
862 int mflags, klassOop caller,
863 int skip, objArrayOop results) {
864 DEBUG_ONLY(No_Safepoint_Verifier nsv);
865 // this code contains no safepoints!
866
867 // %%% take caller into account!
868
869 if (k == NULL || !Klass::cast(k)->oop_is_instance()) return -1;
870
871 int rfill = 0, rlimit = results->length(), rskip = skip;
872 // overflow measurement:
873 int overflow = 0, overflow_limit = MAX2(1000, rlimit);
874
875 int match_flags = mflags;
876 bool search_superc = ((match_flags & SEARCH_SUPERCLASSES) != 0);
877 bool search_intfc = ((match_flags & SEARCH_INTERFACES) != 0);
878 bool local_only = !(search_superc | search_intfc);
879 bool classes_only = false;
880
881 if (name != NULL) {
882 if (name->utf8_length() == 0) return 0; // a match is not possible
883 }
884 if (sig != NULL) {
885 if (sig->utf8_length() == 0) return 0; // a match is not possible
886 if (sig->byte_at(0) == '(')
887 match_flags &= ~(IS_FIELD | IS_TYPE);
888 else
889 match_flags &= ~(IS_CONSTRUCTOR | IS_METHOD);
890 }
891
892 if ((match_flags & IS_TYPE) != 0) {
893 // NYI, and Core Reflection works quite well for this query
894 }
895
896 if ((match_flags & IS_FIELD) != 0) {
897 for (FieldStream st(k, local_only, !search_intfc); !st.eos(); st.next()) {
898 if (name != NULL && st.name() != name)
899 continue;
900 if (sig != NULL && st.signature() != sig)
901 continue;
902 // passed the filters
903 if (rskip > 0) {
904 --rskip;
905 } else if (rfill < rlimit) {
906 oop result = results->obj_at(rfill++);
907 if (!java_lang_invoke_MemberName::is_instance(result))
908 return -99; // caller bug!
909 MethodHandles::init_MemberName(result, st.klass()->as_klassOop(), st.access_flags(), st.offset());
910 } else if (++overflow >= overflow_limit) {
911 match_flags = 0; break; // got tired of looking at overflow
912 }
913 }
914 }
915
916 if ((match_flags & (IS_METHOD | IS_CONSTRUCTOR)) != 0) {
917 // watch out for these guys:
918 Symbol* init_name = vmSymbols::object_initializer_name();
919 Symbol* clinit_name = vmSymbols::class_initializer_name();
920 if (name == clinit_name) clinit_name = NULL; // hack for exposing <clinit>
921 bool negate_name_test = false;
922 // fix name so that it captures the intention of IS_CONSTRUCTOR
923 if (!(match_flags & IS_METHOD)) {
924 // constructors only
925 if (name == NULL) {
926 name = init_name;
927 } else if (name != init_name) {
928 return 0; // no constructors of this method name
929 }
930 } else if (!(match_flags & IS_CONSTRUCTOR)) {
931 // methods only
932 if (name == NULL) {
933 name = init_name;
934 negate_name_test = true; // if we see the name, we *omit* the entry
935 } else if (name == init_name) {
936 return 0; // no methods of this constructor name
937 }
938 } else {
939 // caller will accept either sort; no need to adjust name
940 }
941 for (MethodStream st(k, local_only, !search_intfc); !st.eos(); st.next()) {
942 methodOop m = st.method();
943 Symbol* m_name = m->name();
944 if (m_name == clinit_name)
945 continue;
946 if (name != NULL && ((m_name != name) ^ negate_name_test))
947 continue;
948 if (sig != NULL && m->signature() != sig)
949 continue;
950 // passed the filters
951 if (rskip > 0) {
952 --rskip;
953 } else if (rfill < rlimit) {
954 oop result = results->obj_at(rfill++);
955 if (!java_lang_invoke_MemberName::is_instance(result))
956 return -99; // caller bug!
957 MethodHandles::init_MemberName(result, m, true);
958 } else if (++overflow >= overflow_limit) {
959 match_flags = 0; break; // got tired of looking at overflow
960 }
961 }
962 }
963
964 // return number of elements we at leasted wanted to initialize
965 return rfill + overflow;
966 }
967
968
969 // Decode this java.lang.Class object into an instanceKlass, if possible.
970 // Throw IAE if not
971 instanceKlassHandle MethodHandles::resolve_instance_klass(oop java_mirror_oop, TRAPS) {
972 instanceKlassHandle empty;
973 klassOop caller = NULL;
974 if (java_lang_Class::is_instance(java_mirror_oop)) {
975 caller = java_lang_Class::as_klassOop(java_mirror_oop);
976 }
977 if (caller == NULL || !Klass::cast(caller)->oop_is_instance()) {
978 THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "not a class", empty);
979 }
980 return instanceKlassHandle(THREAD, caller);
981 }
982
983
984
985 // Decode the vmtarget field of a method handle.
986 // Sanitize out methodOops, klassOops, and any other non-Java data.
987 // This is for debugging and reflection.
988 oop MethodHandles::encode_target(Handle mh, int format, TRAPS) {
989 assert(java_lang_invoke_MethodHandle::is_instance(mh()), "must be a MH");
990 if (format == ETF_HANDLE_OR_METHOD_NAME) {
991 oop target = java_lang_invoke_MethodHandle::vmtarget(mh());
992 if (target == NULL) {
993 return NULL; // unformed MH
994 }
995 klassOop tklass = target->klass();
996 if (Klass::cast(tklass)->is_subclass_of(SystemDictionary::Object_klass())) {
997 return target; // target is another MH (or something else?)
998 }
999 }
1000 if (format == ETF_DIRECT_HANDLE) {
1001 oop target = mh();
1002 for (;;) {
1003 if (target->klass() == SystemDictionary::DirectMethodHandle_klass()) {
1004 return target;
1005 }
1006 if (!java_lang_invoke_MethodHandle::is_instance(target)){
1007 return NULL; // unformed MH
1008 }
1009 target = java_lang_invoke_MethodHandle::vmtarget(target);
1010 }
1011 }
1012 // cases of metadata in MH.vmtarget:
1013 // - AMH can have methodOop for static invoke with bound receiver
1014 // - DMH can have methodOop for static invoke (on variable receiver)
1015 // - DMH can have klassOop for dispatched (non-static) invoke
1016 KlassHandle receiver_limit; int decode_flags = 0;
1017 methodHandle m = decode_MethodHandle(mh(), receiver_limit, decode_flags);
1018 if (m.is_null()) return NULL;
1019 switch (format) {
1020 case ETF_REFLECT_METHOD:
1021 // same as jni_ToReflectedMethod:
1022 if (m->is_initializer()) {
1023 return Reflection::new_constructor(m, THREAD);
1024 } else {
1025 return Reflection::new_method(m, UseNewReflection, false, THREAD);
1026 }
1027
1028 case ETF_HANDLE_OR_METHOD_NAME: // method, not handle
1029 case ETF_METHOD_NAME:
1030 {
1031 if (SystemDictionary::MemberName_klass() == NULL) break;
1032 instanceKlassHandle mname_klass(THREAD, SystemDictionary::MemberName_klass());
1033 mname_klass->initialize(CHECK_NULL);
1034 Handle mname = mname_klass->allocate_instance_handle(CHECK_NULL); // possible safepoint
1035 java_lang_invoke_MemberName::set_vmindex(mname(), VM_INDEX_UNINITIALIZED);
1036 bool do_dispatch = ((decode_flags & MethodHandles::_dmf_does_dispatch) != 0);
1037 init_MemberName(mname(), m(), do_dispatch);
1038 expand_MemberName(mname, 0, CHECK_NULL);
1039 return mname();
1040 }
1041 }
1042
1043 // Unknown format code.
1044 char msg[50];
1045 jio_snprintf(msg, sizeof(msg), "unknown getTarget format=%d", format);
1046 THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), msg);
1047 }
1048
1049 static const char* always_null_names[] = {
1050 "java/lang/Void",
1051 "java/lang/Null",
1052 //"java/lang/Nothing",
1053 "sun/dyn/empty/Empty",
1054 "sun/invoke/empty/Empty",
1055 NULL
1056 };
1057
1058 static bool is_always_null_type(klassOop klass) {
1059 if (klass == NULL) return false; // safety
1060 if (!Klass::cast(klass)->oop_is_instance()) return false;
1061 instanceKlass* ik = instanceKlass::cast(klass);
1062 // Must be on the boot class path:
1063 if (ik->class_loader() != NULL) return false;
1064 // Check the name.
1065 Symbol* name = ik->name();
1066 for (int i = 0; ; i++) {
1067 const char* test_name = always_null_names[i];
1068 if (test_name == NULL) break;
1069 if (name->equals(test_name))
1070 return true;
1071 }
1072 return false;
1073 }
1074
1075 bool MethodHandles::class_cast_needed(klassOop src, klassOop dst) {
1076 if (dst == NULL) return true;
1077 if (src == NULL) return (dst != SystemDictionary::Object_klass());
1078 if (src == dst || dst == SystemDictionary::Object_klass())
1079 return false; // quickest checks
1080 Klass* srck = Klass::cast(src);
1081 Klass* dstk = Klass::cast(dst);
1082 if (dstk->is_interface()) {
1083 // interface receivers can safely be viewed as untyped,
1084 // because interface calls always include a dynamic check
1085 //dstk = Klass::cast(SystemDictionary::Object_klass());
1086 return false;
1087 }
1088 if (srck->is_interface()) {
1089 // interface arguments must be viewed as untyped
1090 //srck = Klass::cast(SystemDictionary::Object_klass());
1091 return true;
1092 }
1093 if (is_always_null_type(src)) {
1094 // some source types are known to be never instantiated;
1095 // they represent references which are always null
1096 // such null references never fail to convert safely
1097 return false;
1098 }
1099 return !srck->is_subclass_of(dstk->as_klassOop());
1100 }
1101
1102 static oop object_java_mirror() {
1103 return Klass::cast(SystemDictionary::Object_klass())->java_mirror();
1104 }
1105
1106 bool MethodHandles::is_float_fixed_reinterpretation_cast(BasicType src, BasicType dst) {
1107 if (src == T_FLOAT) return dst == T_INT;
1108 if (src == T_INT) return dst == T_FLOAT;
1109 if (src == T_DOUBLE) return dst == T_LONG;
1110 if (src == T_LONG) return dst == T_DOUBLE;
1111 return false;
1112 }
1113
1114 bool MethodHandles::same_basic_type_for_arguments(BasicType src,
1115 BasicType dst,
1116 bool raw,
1117 bool for_return) {
1118 if (for_return) {
1119 // return values can always be forgotten:
1120 if (dst == T_VOID) return true;
1121 if (src == T_VOID) return raw && (dst == T_INT);
1122 // We allow caller to receive a garbage int, which is harmless.
1123 // This trick is pulled by trusted code (see VerifyType.canPassRaw).
1124 }
1125 assert(src != T_VOID && dst != T_VOID, "should not be here");
1126 if (src == dst) return true;
1127 if (type2size[src] != type2size[dst]) return false;
1128 if (src == T_OBJECT || dst == T_OBJECT) return false;
1129 if (raw) return true; // bitwise reinterpretation; caller guarantees safety
1130 // allow reinterpretation casts for integral widening
1131 if (is_subword_type(src)) { // subwords can fit in int or other subwords
1132 if (dst == T_INT) // any subword fits in an int
1133 return true;
1134 if (src == T_BOOLEAN) // boolean fits in any subword
1135 return is_subword_type(dst);
1136 if (src == T_BYTE && dst == T_SHORT)
1137 return true; // remaining case: byte fits in short
1138 }
1139 // allow float/fixed reinterpretation casts
1140 if (is_float_fixed_reinterpretation_cast(src, dst))
1141 return true;
1142 return false;
1143 }
1144
1145 const char* MethodHandles::check_method_receiver(methodOop m,
1146 klassOop passed_recv_type) {
1147 assert(!m->is_static(), "caller resp.");
1148 if (passed_recv_type == NULL)
1149 return "receiver type is primitive";
1150 if (class_cast_needed(passed_recv_type, m->method_holder())) {
1151 Klass* formal = Klass::cast(m->method_holder());
1152 return SharedRuntime::generate_class_cast_message("receiver type",
1153 formal->external_name());
1154 }
1155 return NULL; // checks passed
1156 }
1157
1158 // Verify that m's signature can be called type-safely by a method handle
1159 // of the given method type 'mtype'.
1160 // It takes a TRAPS argument because it must perform symbol lookups.
1161 void MethodHandles::verify_method_signature(methodHandle m,
1162 Handle mtype,
1163 int first_ptype_pos,
1164 KlassHandle insert_ptype,
1165 TRAPS) {
1166 Handle mhi_type;
1167 if (m->is_method_handle_invoke()) {
1168 // use this more exact typing instead of the symbolic signature:
1169 mhi_type = Handle(THREAD, m->method_handle_type());
1170 }
1171 objArrayHandle ptypes(THREAD, java_lang_invoke_MethodType::ptypes(mtype()));
1172 int pnum = first_ptype_pos;
1173 int pmax = ptypes->length();
1174 int anum = 0; // method argument
1175 const char* err = NULL;
1176 ResourceMark rm(THREAD);
1177 for (SignatureStream ss(m->signature()); !ss.is_done(); ss.next()) {
1178 oop ptype_oop = NULL;
1179 if (ss.at_return_type()) {
1180 if (pnum != pmax)
1181 { err = "too many arguments"; break; }
1182 ptype_oop = java_lang_invoke_MethodType::rtype(mtype());
1183 } else {
1184 if (pnum >= pmax)
1185 { err = "not enough arguments"; break; }
1186 if (pnum >= 0)
1187 ptype_oop = ptypes->obj_at(pnum);
1188 else if (insert_ptype.is_null())
1189 ptype_oop = NULL;
1190 else
1191 ptype_oop = insert_ptype->java_mirror();
1192 pnum += 1;
1193 anum += 1;
1194 }
1195 KlassHandle pklass;
1196 BasicType ptype = T_OBJECT;
1197 bool have_ptype = false;
1198 // missing ptype_oop does not match any non-reference; use Object to report the error
1199 pklass = SystemDictionaryHandles::Object_klass();
1200 if (ptype_oop != NULL) {
1201 have_ptype = true;
1202 klassOop pklass_oop = NULL;
1203 ptype = java_lang_Class::as_BasicType(ptype_oop, &pklass_oop);
1204 pklass = KlassHandle(THREAD, pklass_oop);
1205 }
1206 ptype_oop = NULL; //done with this
1207 KlassHandle aklass;
1208 BasicType atype = ss.type();
1209 if (atype == T_ARRAY) atype = T_OBJECT; // fold all refs to T_OBJECT
1210 if (atype == T_OBJECT) {
1211 if (!have_ptype) {
1212 // null matches any reference
1213 continue;
1214 }
1215 if (mhi_type.is_null()) {
1216 // If we fail to resolve types at this point, we will usually throw an error.
1217 TempNewSymbol name = ss.as_symbol_or_null();
1218 if (name != NULL) {
1219 instanceKlass* mk = instanceKlass::cast(m->method_holder());
1220 Handle loader(THREAD, mk->class_loader());
1221 Handle domain(THREAD, mk->protection_domain());
1222 klassOop aklass_oop = SystemDictionary::resolve_or_null(name, loader, domain, CHECK);
1223 if (aklass_oop != NULL)
1224 aklass = KlassHandle(THREAD, aklass_oop);
1225 }
1226 } else {
1227 // for method handle invokers we don't look at the name in the signature
1228 oop atype_oop;
1229 if (ss.at_return_type())
1230 atype_oop = java_lang_invoke_MethodType::rtype(mhi_type());
1231 else
1232 atype_oop = java_lang_invoke_MethodType::ptype(mhi_type(), anum-1);
1233 klassOop aklass_oop = NULL;
1234 atype = java_lang_Class::as_BasicType(atype_oop, &aklass_oop);
1235 aklass = KlassHandle(THREAD, aklass_oop);
1236 }
1237 }
1238 if (!ss.at_return_type()) {
1239 err = check_argument_type_change(ptype, pklass(), atype, aklass(), anum);
1240 } else {
1241 err = check_return_type_change(atype, aklass(), ptype, pklass()); // note reversal!
1242 }
1243 if (err != NULL) break;
1244 }
1245
1246 if (err != NULL) {
1247 #ifndef PRODUCT
1248 if (PrintMiscellaneous && (Verbose || WizardMode)) {
1249 tty->print("*** verify_method_signature failed: ");
1250 java_lang_invoke_MethodType::print_signature(mtype(), tty);
1251 tty->cr();
1252 tty->print_cr(" first_ptype_pos = %d, insert_ptype = "UINTX_FORMAT, first_ptype_pos, insert_ptype());
1253 tty->print(" Failing method: ");
1254 m->print();
1255 }
1256 #endif //PRODUCT
1257 THROW_MSG(vmSymbols::java_lang_InternalError(), err);
1258 }
1259 }
1260
1261 // Main routine for verifying the MethodHandle.type of a proposed
1262 // direct or bound-direct method handle.
1263 void MethodHandles::verify_method_type(methodHandle m,
1264 Handle mtype,
1265 bool has_bound_recv,
1266 KlassHandle bound_recv_type,
1267 TRAPS) {
1268 bool m_needs_receiver = !m->is_static();
1269
1270 const char* err = NULL;
1271
1272 int first_ptype_pos = m_needs_receiver ? 1 : 0;
1273 if (has_bound_recv) {
1274 first_ptype_pos -= 1; // ptypes do not include the bound argument; start earlier in them
1275 if (m_needs_receiver && bound_recv_type.is_null())
1276 { err = "bound receiver is not an object"; goto die; }
1277 }
1278
1279 if (m_needs_receiver && err == NULL) {
1280 objArrayOop ptypes = java_lang_invoke_MethodType::ptypes(mtype());
1281 if (ptypes->length() < first_ptype_pos)
1282 { err = "receiver argument is missing"; goto die; }
1283 if (has_bound_recv)
1284 err = check_method_receiver(m(), bound_recv_type->as_klassOop());
1285 else
1286 err = check_method_receiver(m(), java_lang_Class::as_klassOop(ptypes->obj_at(first_ptype_pos-1)));
1287 if (err != NULL) goto die;
1288 }
1289
1290 // Check the other arguments for mistypes.
1291 verify_method_signature(m, mtype, first_ptype_pos, bound_recv_type, CHECK);
1292 return;
1293
1294 die:
1295 THROW_MSG(vmSymbols::java_lang_InternalError(), err);
1296 }
1297
1298 void MethodHandles::verify_vmslots(Handle mh, TRAPS) {
1299 // Verify vmslots.
1300 int check_slots = argument_slot_count(java_lang_invoke_MethodHandle::type(mh()));
1301 if (java_lang_invoke_MethodHandle::vmslots(mh()) != check_slots) {
1302 THROW_MSG(vmSymbols::java_lang_InternalError(), "bad vmslots in BMH");
1303 }
1304 }
1305
1306 void MethodHandles::verify_vmargslot(Handle mh, int argnum, int argslot, TRAPS) {
1307 // Verify that argslot points at the given argnum.
1308 int check_slot = argument_slot(java_lang_invoke_MethodHandle::type(mh()), argnum);
1309 if (argslot != check_slot || argslot < 0) {
1310 ResourceMark rm;
1311 const char* fmt = "for argnum of %d, vmargslot is %d, should be %d";
1312 size_t msglen = strlen(fmt) + 3*11 + 1;
1313 char* msg = NEW_RESOURCE_ARRAY(char, msglen);
1314 jio_snprintf(msg, msglen, fmt, argnum, argslot, check_slot);
1315 THROW_MSG(vmSymbols::java_lang_InternalError(), msg);
1316 }
1317 }
1318
1319 // Verify the correspondence between two method types.
1320 // Apart from the advertised changes, caller method type X must
1321 // be able to invoke the callee method Y type with no violations
1322 // of type integrity.
1323 // Return NULL if all is well, else a short error message.
1324 const char* MethodHandles::check_method_type_change(oop src_mtype, int src_beg, int src_end,
1325 int insert_argnum, oop insert_type,
1326 int change_argnum, oop change_type,
1327 int delete_argnum,
1328 oop dst_mtype, int dst_beg, int dst_end,
1329 bool raw) {
1330 objArrayOop src_ptypes = java_lang_invoke_MethodType::ptypes(src_mtype);
1331 objArrayOop dst_ptypes = java_lang_invoke_MethodType::ptypes(dst_mtype);
1332
1333 int src_max = src_ptypes->length();
1334 int dst_max = dst_ptypes->length();
1335
1336 if (src_end == -1) src_end = src_max;
1337 if (dst_end == -1) dst_end = dst_max;
1338
1339 assert(0 <= src_beg && src_beg <= src_end && src_end <= src_max, "oob");
1340 assert(0 <= dst_beg && dst_beg <= dst_end && dst_end <= dst_max, "oob");
1341
1342 // pending actions; set to -1 when done:
1343 int ins_idx = insert_argnum, chg_idx = change_argnum, del_idx = delete_argnum;
1344
1345 const char* err = NULL;
1346
1347 // Walk along each array of parameter types, including a virtual
1348 // NULL end marker at the end of each.
1349 for (int src_idx = src_beg, dst_idx = dst_beg;
1350 (src_idx <= src_end && dst_idx <= dst_end);
1351 src_idx++, dst_idx++) {
1352 oop src_type = (src_idx == src_end) ? oop(NULL) : src_ptypes->obj_at(src_idx);
1353 oop dst_type = (dst_idx == dst_end) ? oop(NULL) : dst_ptypes->obj_at(dst_idx);
1354 bool fix_null_src_type = false;
1355
1356 // Perform requested edits.
1357 if (ins_idx == src_idx) {
1358 // note that the inserted guy is never affected by a change or deletion
1359 ins_idx = -1;
1360 src_type = insert_type;
1361 fix_null_src_type = true;
1362 --src_idx; // back up to process src type on next loop
1363 src_idx = src_end;
1364 } else {
1365 // note that the changed guy can be immediately deleted
1366 if (chg_idx == src_idx) {
1367 chg_idx = -1;
1368 assert(src_idx < src_end, "oob");
1369 src_type = change_type;
1370 fix_null_src_type = true;
1371 }
1372 if (del_idx == src_idx) {
1373 del_idx = -1;
1374 assert(src_idx < src_end, "oob");
1375 --dst_idx;
1376 continue; // rerun loop after skipping this position
1377 }
1378 }
1379
1380 if (src_type == NULL && fix_null_src_type)
1381 // explicit null in this case matches any dest reference
1382 src_type = (java_lang_Class::is_primitive(dst_type) ? object_java_mirror() : dst_type);
1383
1384 // Compare the two argument types.
1385 if (src_type != dst_type) {
1386 if (src_type == NULL) return "not enough arguments";
1387 if (dst_type == NULL) return "too many arguments";
1388 err = check_argument_type_change(src_type, dst_type, dst_idx, raw);
1389 if (err != NULL) return err;
1390 }
1391 }
1392
1393 // Now compare return types also.
1394 oop src_rtype = java_lang_invoke_MethodType::rtype(src_mtype);
1395 oop dst_rtype = java_lang_invoke_MethodType::rtype(dst_mtype);
1396 if (src_rtype != dst_rtype) {
1397 err = check_return_type_change(dst_rtype, src_rtype, raw); // note reversal!
1398 if (err != NULL) return err;
1399 }
1400
1401 assert(err == NULL, "");
1402 return NULL; // all is well
1403 }
1404
1405
1406 const char* MethodHandles::check_argument_type_change(BasicType src_type,
1407 klassOop src_klass,
1408 BasicType dst_type,
1409 klassOop dst_klass,
1410 int argnum,
1411 bool raw) {
1412 const char* err = NULL;
1413 const bool for_return = (argnum < 0);
1414
1415 // just in case:
1416 if (src_type == T_ARRAY) src_type = T_OBJECT;
1417 if (dst_type == T_ARRAY) dst_type = T_OBJECT;
1418
1419 // Produce some nice messages if VerifyMethodHandles is turned on:
1420 if (!same_basic_type_for_arguments(src_type, dst_type, raw, for_return)) {
1421 if (src_type == T_OBJECT) {
1422 if (raw && is_java_primitive(dst_type))
1423 return NULL; // ref-to-prim discards ref and returns zero
1424 err = (!for_return
1425 ? "type mismatch: passing a %s for method argument #%d, which expects primitive %s"
1426 : "type mismatch: returning a %s, but caller expects primitive %s");
1427 } else if (dst_type == T_OBJECT) {
1428 err = (!for_return
1429 ? "type mismatch: passing a primitive %s for method argument #%d, which expects %s"
1430 : "type mismatch: returning a primitive %s, but caller expects %s");
1431 } else {
1432 err = (!for_return
1433 ? "type mismatch: passing a %s for method argument #%d, which expects %s"
1434 : "type mismatch: returning a %s, but caller expects %s");
1435 }
1436 } else if (src_type == T_OBJECT && dst_type == T_OBJECT &&
1437 class_cast_needed(src_klass, dst_klass)) {
1438 if (!class_cast_needed(dst_klass, src_klass)) {
1439 if (raw)
1440 return NULL; // reverse cast is OK; the MH target is trusted to enforce it
1441 err = (!for_return
1442 ? "cast required: passing a %s for method argument #%d, which expects %s"
1443 : "cast required: returning a %s, but caller expects %s");
1444 } else {
1445 err = (!for_return
1446 ? "reference mismatch: passing a %s for method argument #%d, which expects %s"
1447 : "reference mismatch: returning a %s, but caller expects %s");
1448 }
1449 } else {
1450 // passed the obstacle course
1451 return NULL;
1452 }
1453
1454 // format, format, format
1455 const char* src_name = type2name(src_type);
1456 const char* dst_name = type2name(dst_type);
1457 if (src_name == NULL) src_name = "unknown type";
1458 if (dst_name == NULL) dst_name = "unknown type";
1459 if (src_type == T_OBJECT)
1460 src_name = (src_klass != NULL) ? Klass::cast(src_klass)->external_name() : "an unresolved class";
1461 if (dst_type == T_OBJECT)
1462 dst_name = (dst_klass != NULL) ? Klass::cast(dst_klass)->external_name() : "an unresolved class";
1463
1464 size_t msglen = strlen(err) + strlen(src_name) + strlen(dst_name) + (argnum < 10 ? 1 : 11);
1465 char* msg = NEW_RESOURCE_ARRAY(char, msglen + 1);
1466 if (!for_return) {
1467 assert(strstr(err, "%d") != NULL, "");
1468 jio_snprintf(msg, msglen, err, src_name, argnum, dst_name);
1469 } else {
1470 assert(strstr(err, "%d") == NULL, "");
1471 jio_snprintf(msg, msglen, err, src_name, dst_name);
1472 }
1473 return msg;
1474 }
1475
1476 // Compute the depth within the stack of the given argument, i.e.,
1477 // the combined size of arguments to the right of the given argument.
1478 // For the last argument (ptypes.length-1) this will be zero.
1479 // For the first argument (0) this will be the size of all
1480 // arguments but that one. For the special number -1, this
1481 // will be the size of all arguments, including the first.
1482 // If the argument is neither -1 nor a valid argument index,
1483 // then return a negative number. Otherwise, the result
1484 // is in the range [0..vmslots] inclusive.
1485 int MethodHandles::argument_slot(oop method_type, int arg) {
1486 objArrayOop ptypes = java_lang_invoke_MethodType::ptypes(method_type);
1487 int argslot = 0;
1488 int len = ptypes->length();
1489 if (arg < -1 || arg >= len) return -99;
1490 for (int i = len-1; i > arg; i--) {
1491 BasicType bt = java_lang_Class::as_BasicType(ptypes->obj_at(i));
1492 argslot += type2size[bt];
1493 }
1494 assert(argument_slot_to_argnum(method_type, argslot) == arg, "inverse works");
1495 return argslot;
1496 }
1497
1498 // Given a slot number, return the argument number.
1499 int MethodHandles::argument_slot_to_argnum(oop method_type, int query_argslot) {
1500 objArrayOop ptypes = java_lang_invoke_MethodType::ptypes(method_type);
1501 int argslot = 0;
1502 int len = ptypes->length();
1503 for (int i = len-1; i >= 0; i--) {
1504 if (query_argslot == argslot) return i;
1505 BasicType bt = java_lang_Class::as_BasicType(ptypes->obj_at(i));
1506 argslot += type2size[bt];
1507 }
1508 // return pseudo-arg deepest in stack:
1509 if (query_argslot == argslot) return -1;
1510 return -99; // oob slot, or splitting a double-slot arg
1511 }
1512
1513 methodHandle MethodHandles::dispatch_decoded_method(methodHandle m,
1514 KlassHandle receiver_limit,
1515 int decode_flags,
1516 KlassHandle receiver_klass,
1517 TRAPS) {
1518 assert((decode_flags & ~_DMF_DIRECT_MASK) == 0, "must be direct method reference");
1519 assert((decode_flags & _dmf_has_receiver) != 0, "must have a receiver or first reference argument");
1520
1521 if (!m->is_static() &&
1522 (receiver_klass.is_null() || !receiver_klass->is_subtype_of(m->method_holder())))
1523 // given type does not match class of method, or receiver is null!
1524 // caller should have checked this, but let's be extra careful...
1525 return methodHandle();
1526
1527 if (receiver_limit.not_null() &&
1528 (receiver_klass.not_null() && !receiver_klass->is_subtype_of(receiver_limit())))
1529 // given type is not limited to the receiver type
1530 // note that a null receiver can match any reference value, for a static method
1531 return methodHandle();
1532
1533 if (!(decode_flags & MethodHandles::_dmf_does_dispatch)) {
1534 // pre-dispatched or static method (null receiver is OK for static)
1535 return m;
1536
1537 } else if (receiver_klass.is_null()) {
1538 // null receiver value; cannot dispatch
1539 return methodHandle();
1540
1541 } else if (!(decode_flags & MethodHandles::_dmf_from_interface)) {
1542 // perform virtual dispatch
1543 int vtable_index = m->vtable_index();
1544 guarantee(vtable_index >= 0, "valid vtable index");
1545
1546 // receiver_klass might be an arrayKlassOop but all vtables start at
1547 // the same place. The cast is to avoid virtual call and assertion.
1548 // See also LinkResolver::runtime_resolve_virtual_method.
1549 instanceKlass* inst = (instanceKlass*)Klass::cast(receiver_klass());
1550 DEBUG_ONLY(inst->verify_vtable_index(vtable_index));
1551 methodOop m_oop = inst->method_at_vtable(vtable_index);
1552 return methodHandle(THREAD, m_oop);
1553
1554 } else {
1555 // perform interface dispatch
1556 int itable_index = klassItable::compute_itable_index(m());
1557 guarantee(itable_index >= 0, "valid itable index");
1558 instanceKlass* inst = instanceKlass::cast(receiver_klass());
1559 methodOop m_oop = inst->method_at_itable(m->method_holder(), itable_index, THREAD);
1560 return methodHandle(THREAD, m_oop);
1561 }
1562 }
1563
1564 void MethodHandles::verify_DirectMethodHandle(Handle mh, methodHandle m, TRAPS) {
1565 // Verify type.
1566 Handle mtype(THREAD, java_lang_invoke_MethodHandle::type(mh()));
1567 verify_method_type(m, mtype, false, KlassHandle(), CHECK);
1568
1569 // Verify vmslots.
1570 if (java_lang_invoke_MethodHandle::vmslots(mh()) != m->size_of_parameters()) {
1571 THROW_MSG(vmSymbols::java_lang_InternalError(), "bad vmslots in DMH");
1572 }
1573 }
1574
1575 void MethodHandles::init_DirectMethodHandle(Handle mh, methodHandle m, bool do_dispatch, TRAPS) {
1576 // Check arguments.
1577 if (mh.is_null() || m.is_null() ||
1578 (!do_dispatch && m->is_abstract())) {
1579 THROW(vmSymbols::java_lang_InternalError());
1580 }
1581
1582 java_lang_invoke_MethodHandle::init_vmslots(mh());
1583
1584 if (VerifyMethodHandles) {
1585 // The privileged code which invokes this routine should not make
1586 // a mistake about types, but it's better to verify.
1587 verify_DirectMethodHandle(mh, m, CHECK);
1588 }
1589
1590 // Finally, after safety checks are done, link to the target method.
1591 // We will follow the same path as the latter part of
1592 // InterpreterRuntime::resolve_invoke(), which first finds the method
1593 // and then decides how to populate the constant pool cache entry
1594 // that links the interpreter calls to the method. We need the same
1595 // bits, and will use the same calling sequence code.
1596
1597 int vmindex = methodOopDesc::garbage_vtable_index;
1598 Handle vmtarget;
1599
1600 instanceKlass::cast(m->method_holder())->link_class(CHECK);
1601
1602 MethodHandleEntry* me = NULL;
1603 if (do_dispatch && Klass::cast(m->method_holder())->is_interface()) {
1604 // We are simulating an invokeinterface instruction.
1605 // (We might also be simulating an invokevirtual on a miranda method,
1606 // but it is safe to treat it as an invokeinterface.)
1607 assert(!m->can_be_statically_bound(), "no final methods on interfaces");
1608 vmindex = klassItable::compute_itable_index(m());
1609 assert(vmindex >= 0, "(>=0) == do_dispatch");
1610 // Set up same bits as ConstantPoolCacheEntry::set_interface_call().
1611 vmtarget = m->method_holder(); // the interface
1612 me = MethodHandles::entry(MethodHandles::_invokeinterface_mh);
1613 } else if (!do_dispatch || m->can_be_statically_bound()) {
1614 // We are simulating an invokestatic or invokespecial instruction.
1615 // Set up the method pointer, just like ConstantPoolCacheEntry::set_method().
1616 vmtarget = m;
1617 // this does not help dispatch, but it will make it possible to parse this MH:
1618 vmindex = methodOopDesc::nonvirtual_vtable_index;
1619 assert(vmindex < 0, "(>=0) == do_dispatch");
1620 if (!m->is_static()) {
1621 me = MethodHandles::entry(MethodHandles::_invokespecial_mh);
1622 } else {
1623 me = MethodHandles::entry(MethodHandles::_invokestatic_mh);
1624 // Part of the semantics of a static call is an initialization barrier.
1625 // For a DMH, it is done now, when the handle is created.
1626 Klass* k = Klass::cast(m->method_holder());
1627 if (k->should_be_initialized()) {
1628 k->initialize(CHECK); // possible safepoint
1629 }
1630 }
1631 } else {
1632 // We are simulating an invokevirtual instruction.
1633 // Set up the vtable index, just like ConstantPoolCacheEntry::set_method().
1634 // The key logic is LinkResolver::runtime_resolve_virtual_method.
1635 vmindex = m->vtable_index();
1636 vmtarget = m->method_holder();
1637 me = MethodHandles::entry(MethodHandles::_invokevirtual_mh);
1638 }
1639
1640 if (me == NULL) { THROW(vmSymbols::java_lang_InternalError()); }
1641
1642 java_lang_invoke_DirectMethodHandle::set_vmtarget(mh(), vmtarget());
1643 java_lang_invoke_DirectMethodHandle::set_vmindex( mh(), vmindex);
1644 DEBUG_ONLY(KlassHandle rlimit; int flags);
1645 assert(MethodHandles::decode_method(mh(), rlimit, flags) == m,
1646 "properly stored for later decoding");
1647 DEBUG_ONLY(bool actual_do_dispatch = ((flags & _dmf_does_dispatch) != 0));
1648 assert(!(actual_do_dispatch && !do_dispatch),
1649 "do not perform dispatch if !do_dispatch specified");
1650 assert(actual_do_dispatch == (vmindex >= 0), "proper later decoding of do_dispatch");
1651 assert(decode_MethodHandle_stack_pushes(mh()) == 0, "DMH does not move stack");
1652
1653 // Done!
1654 java_lang_invoke_MethodHandle::set_vmentry(mh(), me);
1655 }
1656
1657 void MethodHandles::verify_BoundMethodHandle_with_receiver(Handle mh,
1658 methodHandle m,
1659 TRAPS) {
1660 // Verify type.
1661 KlassHandle bound_recv_type;
1662 {
1663 oop receiver = java_lang_invoke_BoundMethodHandle::argument(mh());
1664 if (receiver != NULL)
1665 bound_recv_type = KlassHandle(THREAD, receiver->klass());
1666 }
1667 Handle mtype(THREAD, java_lang_invoke_MethodHandle::type(mh()));
1668 verify_method_type(m, mtype, true, bound_recv_type, CHECK);
1669
1670 int receiver_pos = m->size_of_parameters() - 1;
1671
1672 // Verify MH.vmargslot, which should point at the bound receiver.
1673 verify_vmargslot(mh, -1, java_lang_invoke_BoundMethodHandle::vmargslot(mh()), CHECK);
1674 //verify_vmslots(mh, CHECK);
1675
1676 // Verify vmslots.
1677 if (java_lang_invoke_MethodHandle::vmslots(mh()) != receiver_pos) {
1678 THROW_MSG(vmSymbols::java_lang_InternalError(), "bad vmslots in BMH (receiver)");
1679 }
1680 }
1681
1682 // Initialize a BMH with a receiver bound directly to a methodOop.
1683 void MethodHandles::init_BoundMethodHandle_with_receiver(Handle mh,
1684 methodHandle original_m,
1685 KlassHandle receiver_limit,
1686 int decode_flags,
1687 TRAPS) {
1688 // Check arguments.
1689 if (mh.is_null() || original_m.is_null()) {
1690 THROW(vmSymbols::java_lang_InternalError());
1691 }
1692
1693 KlassHandle receiver_klass;
1694 {
1695 oop receiver_oop = java_lang_invoke_BoundMethodHandle::argument(mh());
1696 if (receiver_oop != NULL)
1697 receiver_klass = KlassHandle(THREAD, receiver_oop->klass());
1698 }
1699 methodHandle m = dispatch_decoded_method(original_m,
1700 receiver_limit, decode_flags,
1701 receiver_klass,
1702 CHECK);
1703 if (m.is_null()) { THROW(vmSymbols::java_lang_InternalError()); }
1704 if (m->is_abstract()) { THROW(vmSymbols::java_lang_AbstractMethodError()); }
1705
1706 java_lang_invoke_MethodHandle::init_vmslots(mh());
1707 int vmargslot = m->size_of_parameters() - 1;
1708 assert(java_lang_invoke_BoundMethodHandle::vmargslot(mh()) == vmargslot, "");
1709
1710 if (VerifyMethodHandles) {
1711 verify_BoundMethodHandle_with_receiver(mh, m, CHECK);
1712 }
1713
1714 java_lang_invoke_BoundMethodHandle::set_vmtarget(mh(), m());
1715
1716 DEBUG_ONLY(KlassHandle junk1; int junk2);
1717 assert(MethodHandles::decode_method(mh(), junk1, junk2) == m, "properly stored for later decoding");
1718 assert(decode_MethodHandle_stack_pushes(mh()) == 1, "BMH pushes one stack slot");
1719
1720 // Done!
1721 java_lang_invoke_MethodHandle::set_vmentry(mh(), MethodHandles::entry(MethodHandles::_bound_ref_direct_mh));
1722 }
1723
1724 void MethodHandles::verify_BoundMethodHandle(Handle mh, Handle target, int argnum,
1725 bool direct_to_method, TRAPS) {
1726 ResourceMark rm;
1727 Handle ptype_handle(THREAD,
1728 java_lang_invoke_MethodType::ptype(java_lang_invoke_MethodHandle::type(target()), argnum));
1729 KlassHandle ptype_klass;
1730 BasicType ptype = java_lang_Class::as_BasicType(ptype_handle(), &ptype_klass);
1731 int slots_pushed = type2size[ptype];
1732
1733 oop argument = java_lang_invoke_BoundMethodHandle::argument(mh());
1734
1735 const char* err = NULL;
1736
1737 switch (ptype) {
1738 case T_OBJECT:
1739 if (argument != NULL)
1740 // we must implicitly convert from the arg type to the outgoing ptype
1741 err = check_argument_type_change(T_OBJECT, argument->klass(), ptype, ptype_klass(), argnum);
1742 break;
1743
1744 case T_ARRAY: case T_VOID:
1745 assert(false, "array, void do not appear here");
1746 default:
1747 if (ptype != T_INT && !is_subword_type(ptype)) {
1748 err = "unexpected parameter type";
1749 break;
1750 }
1751 // check subrange of Integer.value, if necessary
1752 if (argument == NULL || argument->klass() != SystemDictionary::Integer_klass()) {
1753 err = "bound integer argument must be of type java.lang.Integer";
1754 break;
1755 }
1756 if (ptype != T_INT) {
1757 int value_offset = java_lang_boxing_object::value_offset_in_bytes(T_INT);
1758 jint value = argument->int_field(value_offset);
1759 int vminfo = adapter_unbox_subword_vminfo(ptype);
1760 jint subword = truncate_subword_from_vminfo(value, vminfo);
1761 if (value != subword) {
1762 err = "bound subword value does not fit into the subword type";
1763 break;
1764 }
1765 }
1766 break;
1767 case T_FLOAT:
1768 case T_DOUBLE:
1769 case T_LONG:
1770 {
1771 // we must implicitly convert from the unboxed arg type to the outgoing ptype
1772 BasicType argbox = java_lang_boxing_object::basic_type(argument);
1773 if (argbox != ptype) {
1774 err = check_argument_type_change(T_OBJECT, (argument == NULL
1775 ? SystemDictionary::Object_klass()
1776 : argument->klass()),
1777 ptype, ptype_klass(), argnum);
1778 assert(err != NULL, "this must be an error");
1779 }
1780 break;
1781 }
1782 }
1783
1784 if (err == NULL) {
1785 DEBUG_ONLY(int this_pushes = decode_MethodHandle_stack_pushes(mh()));
1786 if (direct_to_method) {
1787 assert(this_pushes == slots_pushed, "BMH pushes one or two stack slots");
1788 } else {
1789 int target_pushes = decode_MethodHandle_stack_pushes(target());
1790 assert(this_pushes == slots_pushed + target_pushes, "BMH stack motion must be correct");
1791 }
1792 }
1793
1794 if (err == NULL) {
1795 // Verify the rest of the method type.
1796 err = check_method_type_insertion(java_lang_invoke_MethodHandle::type(mh()),
1797 argnum, ptype_handle(),
1798 java_lang_invoke_MethodHandle::type(target()));
1799 }
1800
1801 if (err != NULL) {
1802 THROW_MSG(vmSymbols::java_lang_InternalError(), err);
1803 }
1804 }
1805
1806 void MethodHandles::init_BoundMethodHandle(Handle mh, Handle target, int argnum, TRAPS) {
1807 // Check arguments.
1808 if (mh.is_null() || target.is_null() || !java_lang_invoke_MethodHandle::is_instance(target())) {
1809 THROW(vmSymbols::java_lang_InternalError());
1810 }
1811
1812 java_lang_invoke_MethodHandle::init_vmslots(mh());
1813 int argslot = java_lang_invoke_BoundMethodHandle::vmargslot(mh());
1814
1815 if (VerifyMethodHandles) {
1816 int insert_after = argnum - 1;
1817 verify_vmargslot(mh, insert_after, argslot, CHECK);
1818 verify_vmslots(mh, CHECK);
1819 }
1820
1821 // Get bound type and required slots.
1822 BasicType ptype;
1823 {
1824 oop ptype_oop = java_lang_invoke_MethodType::ptype(java_lang_invoke_MethodHandle::type(target()), argnum);
1825 ptype = java_lang_Class::as_BasicType(ptype_oop);
1826 }
1827 int slots_pushed = type2size[ptype];
1828
1829 // If (a) the target is a direct non-dispatched method handle,
1830 // or (b) the target is a dispatched direct method handle and we
1831 // are binding the receiver, cut out the middle-man.
1832 // Do this by decoding the DMH and using its methodOop directly as vmtarget.
1833 bool direct_to_method = false;
1834 if (OptimizeMethodHandles &&
1835 target->klass() == SystemDictionary::DirectMethodHandle_klass() &&
1836 (argnum != 0 || java_lang_invoke_BoundMethodHandle::argument(mh()) != NULL) &&
1837 (argnum == 0 || java_lang_invoke_DirectMethodHandle::vmindex(target()) < 0)) {
1838 KlassHandle receiver_limit; int decode_flags = 0;
1839 methodHandle m = decode_method(target(), receiver_limit, decode_flags);
1840 if (m.is_null()) { THROW_MSG(vmSymbols::java_lang_InternalError(), "DMH failed to decode"); }
1841 DEBUG_ONLY(int m_vmslots = m->size_of_parameters() - slots_pushed); // pos. of 1st arg.
1842 assert(java_lang_invoke_BoundMethodHandle::vmslots(mh()) == m_vmslots, "type w/ m sig");
1843 if (argnum == 0 && (decode_flags & _dmf_has_receiver) != 0) {
1844 init_BoundMethodHandle_with_receiver(mh, m,
1845 receiver_limit, decode_flags,
1846 CHECK);
1847 return;
1848 }
1849
1850 // Even if it is not a bound receiver, we still might be able
1851 // to bind another argument and still invoke the methodOop directly.
1852 if (!(decode_flags & _dmf_does_dispatch)) {
1853 direct_to_method = true;
1854 java_lang_invoke_BoundMethodHandle::set_vmtarget(mh(), m());
1855 }
1856 }
1857 if (!direct_to_method)
1858 java_lang_invoke_BoundMethodHandle::set_vmtarget(mh(), target());
1859
1860 if (VerifyMethodHandles) {
1861 verify_BoundMethodHandle(mh, target, argnum, direct_to_method, CHECK);
1862 }
1863
1864 // Next question: Is this a ref, int, or long bound value?
1865 MethodHandleEntry* me = NULL;
1866 if (ptype == T_OBJECT) {
1867 if (direct_to_method) me = MethodHandles::entry(_bound_ref_direct_mh);
1868 else me = MethodHandles::entry(_bound_ref_mh);
1869 } else if (slots_pushed == 2) {
1870 if (direct_to_method) me = MethodHandles::entry(_bound_long_direct_mh);
1871 else me = MethodHandles::entry(_bound_long_mh);
1872 } else if (slots_pushed == 1) {
1873 if (direct_to_method) me = MethodHandles::entry(_bound_int_direct_mh);
1874 else me = MethodHandles::entry(_bound_int_mh);
1875 } else {
1876 assert(false, "");
1877 }
1878
1879 // Done!
1880 java_lang_invoke_MethodHandle::set_vmentry(mh(), me);
1881 }
1882
1883 static void throw_InternalError_for_bad_conversion(int conversion, const char* err, TRAPS) {
1884 char msg[200];
1885 jio_snprintf(msg, sizeof(msg), "bad adapter (conversion=0x%08x): %s", conversion, err);
1886 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), msg);
1887 }
1888
1889 void MethodHandles::verify_AdapterMethodHandle(Handle mh, int argnum, TRAPS) {
1890 ResourceMark rm;
1891 jint conversion = java_lang_invoke_AdapterMethodHandle::conversion(mh());
1892 int argslot = java_lang_invoke_AdapterMethodHandle::vmargslot(mh());
1893
1894 verify_vmargslot(mh, argnum, argslot, CHECK);
1895 verify_vmslots(mh, CHECK);
1896
1897 jint conv_op = adapter_conversion_op(conversion);
1898 if (!conv_op_valid(conv_op)) {
1899 throw_InternalError_for_bad_conversion(conversion, "unknown conversion op", THREAD);
1900 return;
1901 }
1902 EntryKind ek = adapter_entry_kind(conv_op);
1903
1904 int stack_move = adapter_conversion_stack_move(conversion);
1905 BasicType src = adapter_conversion_src_type(conversion);
1906 BasicType dest = adapter_conversion_dest_type(conversion);
1907 int vminfo = adapter_conversion_vminfo(conversion); // should be zero
1908
1909 Handle argument(THREAD, java_lang_invoke_AdapterMethodHandle::argument(mh()));
1910 Handle target(THREAD, java_lang_invoke_AdapterMethodHandle::vmtarget(mh()));
1911 Handle src_mtype(THREAD, java_lang_invoke_MethodHandle::type(mh()));
1912 Handle dst_mtype(THREAD, java_lang_invoke_MethodHandle::type(target()));
1913 Handle arg_mtype;
1914
1915 const char* err = NULL;
1916
1917 if (err == NULL) {
1918 // Check that the correct argument is supplied, but only if it is required.
1919 switch (ek) {
1920 case _adapter_check_cast: // target type of cast
1921 case _adapter_ref_to_prim: // wrapper type from which to unbox
1922 case _adapter_spread_args: // array type to spread from
1923 if (!java_lang_Class::is_instance(argument())
1924 || java_lang_Class::is_primitive(argument()))
1925 { err = "adapter requires argument of type java.lang.Class"; break; }
1926 if (ek == _adapter_spread_args) {
1927 // Make sure it is a suitable collection type. (Array, for now.)
1928 Klass* ak = Klass::cast(java_lang_Class::as_klassOop(argument()));
1929 if (!ak->oop_is_array())
1930 { err = "spread adapter requires argument representing an array class"; break; }
1931 BasicType et = arrayKlass::cast(ak->as_klassOop())->element_type();
1932 if (et != dest && stack_move <= 0)
1933 { err = "spread adapter requires array class argument of correct type"; break; }
1934 }
1935 break;
1936 case _adapter_prim_to_ref: // boxer MH to use
1937 case _adapter_collect_args: // method handle which collects the args
1938 case _adapter_fold_args: // method handle which collects the args
1939 if (!UseRicochetFrames) {
1940 { err = "box/collect/fold operators are not supported"; break; }
1941 }
1942 if (!java_lang_invoke_MethodHandle::is_instance(argument()))
1943 { err = "MethodHandle adapter argument required"; break; }
1944 arg_mtype = Handle(THREAD, java_lang_invoke_MethodHandle::type(argument()));
1945 break;
1946 default:
1947 if (argument.not_null())
1948 { err = "adapter has spurious argument"; break; }
1949 break;
1950 }
1951 }
1952
1953 if (err == NULL) {
1954 // Check that the src/dest types are supplied if needed.
1955 // Also check relevant parameter or return types.
1956 switch (ek) {
1957 case _adapter_check_cast:
1958 if (src != T_OBJECT || dest != T_OBJECT) {
1959 err = "adapter requires object src/dest conversion subfields";
1960 }
1961 break;
1962 case _adapter_prim_to_prim:
1963 if (!is_java_primitive(src) || !is_java_primitive(dest) || src == dest) {
1964 err = "adapter requires primitive src/dest conversion subfields"; break;
1965 }
1966 if ( (src == T_FLOAT || src == T_DOUBLE) && !(dest == T_FLOAT || dest == T_DOUBLE) ||
1967 !(src == T_FLOAT || src == T_DOUBLE) && (dest == T_FLOAT || dest == T_DOUBLE)) {
1968 err = "adapter cannot convert beween floating and fixed-point"; break;
1969 }
1970 break;
1971 case _adapter_ref_to_prim:
1972 if (src != T_OBJECT || !is_java_primitive(dest)
1973 || argument() != Klass::cast(SystemDictionary::box_klass(dest))->java_mirror()) {
1974 err = "adapter requires primitive dest conversion subfield"; break;
1975 }
1976 break;
1977 case _adapter_prim_to_ref:
1978 if (!is_java_primitive(src) || dest != T_OBJECT) {
1979 err = "adapter requires primitive src conversion subfield"; break;
1980 }
1981 break;
1982 case _adapter_swap_args:
1983 case _adapter_rot_args:
1984 {
1985 if (!src || src != dest) {
1986 err = "adapter requires src/dest conversion subfields for swap"; break;
1987 }
1988 int swap_size = type2size[src];
1989 int src_slot = argslot;
1990 int dest_slot = vminfo;
1991 bool rotate_up = (src_slot > dest_slot); // upward rotation
1992 int src_arg = argnum;
1993 int dest_arg = argument_slot_to_argnum(dst_mtype(), dest_slot);
1994 verify_vmargslot(target, dest_arg, dest_slot, CHECK);
1995 if (!(dest_slot >= src_slot + swap_size) &&
1996 !(src_slot >= dest_slot + swap_size)) {
1997 err = "source, destination slots must be distinct";
1998 } else if (ek == _adapter_swap_args && !(src_slot > dest_slot)) {
1999 err = "source of swap must be deeper in stack";
2000 } else if (ek == _adapter_swap_args) {
2001 err = check_argument_type_change(java_lang_invoke_MethodType::ptype(src_mtype(), dest_arg),
2002 java_lang_invoke_MethodType::ptype(dst_mtype(), src_arg),
2003 dest_arg);
2004 } else if (ek == _adapter_rot_args) {
2005 if (rotate_up) {
2006 assert((src_slot > dest_slot) && (src_arg < dest_arg), "");
2007 // rotate up: [dest_slot..src_slot-ss] --> [dest_slot+ss..src_slot]
2008 // that is: [src_arg+1..dest_arg] --> [src_arg..dest_arg-1]
2009 for (int i = src_arg+1; i <= dest_arg && err == NULL; i++) {
2010 err = check_argument_type_change(java_lang_invoke_MethodType::ptype(src_mtype(), i),
2011 java_lang_invoke_MethodType::ptype(dst_mtype(), i-1),
2012 i);
2013 }
2014 } else { // rotate down
2015 assert((src_slot < dest_slot) && (src_arg > dest_arg), "");
2016 // rotate down: [src_slot+ss..dest_slot] --> [src_slot..dest_slot-ss]
2017 // that is: [dest_arg..src_arg-1] --> [dst_arg+1..src_arg]
2018 for (int i = dest_arg; i <= src_arg-1 && err == NULL; i++) {
2019 err = check_argument_type_change(java_lang_invoke_MethodType::ptype(src_mtype(), i),
2020 java_lang_invoke_MethodType::ptype(dst_mtype(), i+1),
2021 i);
2022 }
2023 }
2024 }
2025 if (err == NULL)
2026 err = check_argument_type_change(java_lang_invoke_MethodType::ptype(src_mtype(), src_arg),
2027 java_lang_invoke_MethodType::ptype(dst_mtype(), dest_arg),
2028 src_arg);
2029 }
2030 break;
2031 case _adapter_spread_args:
2032 case _adapter_collect_args:
2033 case _adapter_fold_args:
2034 {
2035 bool is_spread = (ek == _adapter_spread_args);
2036 bool is_fold = (ek == _adapter_fold_args);
2037 BasicType coll_type = is_spread ? src : dest;
2038 BasicType elem_type = is_spread ? dest : src;
2039 // coll_type is type of args in collected form (or T_VOID if none)
2040 // elem_type is common type of args in spread form (or T_VOID if missing or heterogeneous)
2041 if (coll_type == 0 || elem_type == 0) {
2042 err = "adapter requires src/dest subfields for spread or collect"; break;
2043 }
2044 if (is_spread && coll_type != T_OBJECT) {
2045 err = "spread adapter requires object type for argument bundle"; break;
2046 }
2047 Handle spread_mtype = (is_spread ? dst_mtype : src_mtype);
2048 int spread_slot = argslot;
2049 int spread_arg = argnum;
2050 int slots_pushed = stack_move / stack_move_unit();
2051 int coll_slot_count = type2size[coll_type];
2052 int spread_slot_count = (is_spread ? slots_pushed : -slots_pushed) + coll_slot_count;
2053 if (is_fold) spread_slot_count = argument_slot_count(arg_mtype());
2054 if (!is_spread) {
2055 int init_slots = argument_slot_count(src_mtype());
2056 int coll_slots = argument_slot_count(arg_mtype());
2057 if (spread_slot_count > init_slots ||
2058 spread_slot_count != coll_slots) {
2059 err = "collect adapter has inconsistent arg counts"; break;
2060 }
2061 int next_slots = argument_slot_count(dst_mtype());
2062 int unchanged_slots_in = (init_slots - spread_slot_count);
2063 int unchanged_slots_out = (next_slots - coll_slot_count - (is_fold ? spread_slot_count : 0));
2064 if (unchanged_slots_in != unchanged_slots_out) {
2065 err = "collect adapter continuation has inconsistent arg counts"; break;
2066 }
2067 }
2068 }
2069 break;
2070 default:
2071 if (src != 0 || dest != 0) {
2072 err = "adapter has spurious src/dest conversion subfields"; break;
2073 }
2074 break;
2075 }
2076 }
2077
2078 if (err == NULL) {
2079 // Check the stack_move subfield.
2080 // It must always report the net change in stack size, positive or negative.
2081 int slots_pushed = stack_move / stack_move_unit();
2082 switch (ek) {
2083 case _adapter_prim_to_prim:
2084 case _adapter_ref_to_prim:
2085 case _adapter_prim_to_ref:
2086 if (slots_pushed != type2size[dest] - type2size[src]) {
2087 err = "wrong stack motion for primitive conversion";
2088 }
2089 break;
2090 case _adapter_dup_args:
2091 if (slots_pushed <= 0) {
2092 err = "adapter requires conversion subfield slots_pushed > 0";
2093 }
2094 break;
2095 case _adapter_drop_args:
2096 if (slots_pushed >= 0) {
2097 err = "adapter requires conversion subfield slots_pushed < 0";
2098 }
2099 break;
2100 case _adapter_collect_args:
2101 case _adapter_fold_args:
2102 if (slots_pushed > 2) {
2103 err = "adapter requires conversion subfield slots_pushed <= 2";
2104 }
2105 break;
2106 case _adapter_spread_args:
2107 if (slots_pushed < -1) {
2108 err = "adapter requires conversion subfield slots_pushed >= -1";
2109 }
2110 break;
2111 default:
2112 if (stack_move != 0) {
2113 err = "adapter has spurious stack_move conversion subfield";
2114 }
2115 break;
2116 }
2117 if (err == NULL && stack_move != slots_pushed * stack_move_unit()) {
2118 err = "stack_move conversion subfield must be multiple of stack_move_unit";
2119 }
2120 }
2121
2122 if (err == NULL) {
2123 // Make sure this adapter's stack pushing is accurately recorded.
2124 int slots_pushed = stack_move / stack_move_unit();
2125 int this_vmslots = java_lang_invoke_MethodHandle::vmslots(mh());
2126 int target_vmslots = java_lang_invoke_MethodHandle::vmslots(target());
2127 int target_pushes = decode_MethodHandle_stack_pushes(target());
2128 if (slots_pushed != (target_vmslots - this_vmslots)) {
2129 err = "stack_move inconsistent with previous and current MethodType vmslots";
2130 } else {
2131 int this_pushes = decode_MethodHandle_stack_pushes(mh());
2132 if (slots_pushed + target_pushes != this_pushes) {
2133 if (this_pushes == 0)
2134 err = "adapter push count not initialized";
2135 else
2136 err = "adapter push count is wrong";
2137 }
2138 }
2139
2140 // While we're at it, check that the stack motion decoder works:
2141 DEBUG_ONLY(int this_pushes = decode_MethodHandle_stack_pushes(mh()));
2142 assert(this_pushes == slots_pushed + target_pushes, "AMH stack motion must be correct");
2143 }
2144
2145 if (err == NULL && vminfo != 0) {
2146 switch (ek) {
2147 case _adapter_swap_args:
2148 case _adapter_rot_args:
2149 case _adapter_prim_to_ref:
2150 case _adapter_collect_args:
2151 case _adapter_fold_args:
2152 break; // OK
2153 default:
2154 err = "vminfo subfield is reserved to the JVM";
2155 }
2156 }
2157
2158 // Do additional ad hoc checks.
2159 if (err == NULL) {
2160 switch (ek) {
2161 case _adapter_retype_only:
2162 err = check_method_type_passthrough(src_mtype(), dst_mtype(), false);
2163 break;
2164
2165 case _adapter_retype_raw:
2166 err = check_method_type_passthrough(src_mtype(), dst_mtype(), true);
2167 break;
2168
2169 case _adapter_check_cast:
2170 {
2171 // The actual value being checked must be a reference:
2172 err = check_argument_type_change(java_lang_invoke_MethodType::ptype(src_mtype(), argnum),
2173 object_java_mirror(), argnum);
2174 if (err != NULL) break;
2175
2176 // The output of the cast must fit with the destination argument:
2177 Handle cast_class = argument;
2178 err = check_method_type_conversion(src_mtype(),
2179 argnum, cast_class(),
2180 dst_mtype());
2181 }
2182 break;
2183
2184 // %%% TO DO: continue in remaining cases to verify src/dst_mtype if VerifyMethodHandles
2185 }
2186 }
2187
2188 if (err != NULL) {
2189 throw_InternalError_for_bad_conversion(conversion, err, THREAD);
2190 return;
2191 }
2192
2193 }
2194
2195 void MethodHandles::init_AdapterMethodHandle(Handle mh, Handle target, int argnum, TRAPS) {
2196 Handle argument = java_lang_invoke_AdapterMethodHandle::argument(mh());
2197 int argslot = java_lang_invoke_AdapterMethodHandle::vmargslot(mh());
2198 jint conversion = java_lang_invoke_AdapterMethodHandle::conversion(mh());
2199 jint conv_op = adapter_conversion_op(conversion);
2200
2201 // adjust the adapter code to the internal EntryKind enumeration:
2202 EntryKind ek_orig = adapter_entry_kind(conv_op);
2203 EntryKind ek_opt = ek_orig; // may be optimized
2204 EntryKind ek_try; // temp
2205
2206 // Finalize the vmtarget field (Java initialized it to null).
2207 if (!java_lang_invoke_MethodHandle::is_instance(target())) {
2208 throw_InternalError_for_bad_conversion(conversion, "bad target", THREAD);
2209 return;
2210 }
2211 java_lang_invoke_AdapterMethodHandle::set_vmtarget(mh(), target());
2212
2213 int stack_move = adapter_conversion_stack_move(conversion);
2214 BasicType src = adapter_conversion_src_type(conversion);
2215 BasicType dest = adapter_conversion_dest_type(conversion);
2216 int vminfo = adapter_conversion_vminfo(conversion); // should be zero
2217
2218 int slots_pushed = stack_move / stack_move_unit();
2219
2220 if (VerifyMethodHandles) {
2221 verify_AdapterMethodHandle(mh, argnum, CHECK);
2222 }
2223
2224 const char* err = NULL;
2225
2226 if (!conv_op_supported(conv_op)) {
2227 err = "adapter not yet implemented in the JVM";
2228 }
2229
2230 // Now it's time to finish the case analysis and pick a MethodHandleEntry.
2231 switch (ek_orig) {
2232 case _adapter_retype_only:
2233 case _adapter_retype_raw:
2234 case _adapter_check_cast:
2235 case _adapter_dup_args:
2236 case _adapter_drop_args:
2237 // these work fine via general case code
2238 break;
2239
2240 case _adapter_prim_to_prim:
2241 {
2242 // Non-subword cases are {int,float,long,double} -> {int,float,long,double}.
2243 // And, the {float,double} -> {int,long} cases must be handled by Java.
2244 switch (type2size[src] *4+ type2size[dest]) {
2245 case 1 *4+ 1:
2246 assert(src == T_INT || is_subword_type(src), "source is not float");
2247 // Subword-related cases are int -> {boolean,byte,char,short}.
2248 ek_opt = _adapter_opt_i2i;
2249 vminfo = adapter_prim_to_prim_subword_vminfo(dest);
2250 break;
2251 case 2 *4+ 1:
2252 if (src == T_LONG && (dest == T_INT || is_subword_type(dest))) {
2253 ek_opt = _adapter_opt_l2i;
2254 vminfo = adapter_prim_to_prim_subword_vminfo(dest);
2255 } else if (src == T_DOUBLE && dest == T_FLOAT) {
2256 ek_opt = _adapter_opt_d2f;
2257 } else {
2258 goto throw_not_impl; // runs user code, hence could block
2259 }
2260 break;
2261 case 1 *4+ 2:
2262 if ((src == T_INT || is_subword_type(src)) && dest == T_LONG) {
2263 ek_opt = _adapter_opt_i2l;
2264 } else if (src == T_FLOAT && dest == T_DOUBLE) {
2265 ek_opt = _adapter_opt_f2d;
2266 } else {
2267 goto throw_not_impl; // runs user code, hence could block
2268 }
2269 break;
2270 default:
2271 goto throw_not_impl; // runs user code, hence could block
2272 break;
2273 }
2274 }
2275 break;
2276
2277 case _adapter_ref_to_prim:
2278 {
2279 switch (type2size[dest]) {
2280 case 1:
2281 ek_opt = _adapter_opt_unboxi;
2282 vminfo = adapter_unbox_subword_vminfo(dest);
2283 break;
2284 case 2:
2285 ek_opt = _adapter_opt_unboxl;
2286 break;
2287 default:
2288 goto throw_not_impl;
2289 break;
2290 }
2291 }
2292 break;
2293
2294 case _adapter_prim_to_ref:
2295 {
2296 assert(UseRicochetFrames, "else don't come here");
2297 // vminfo will be the location to insert the return value
2298 vminfo = argslot;
2299 ek_opt = _adapter_opt_collect_ref;
2300 ensure_vmlayout_field(target, CHECK);
2301 // for MethodHandleWalk:
2302 if (java_lang_invoke_AdapterMethodHandle::is_instance(argument()))
2303 ensure_vmlayout_field(argument, CHECK);
2304 if (!OptimizeMethodHandles) break;
2305 switch (type2size[src]) {
2306 case 1:
2307 ek_try = EntryKind(_adapter_opt_filter_S0_ref + argslot);
2308 if (ek_try < _adapter_opt_collect_LAST &&
2309 ek_adapter_opt_collect_slot(ek_try) == argslot) {
2310 assert(ek_adapter_opt_collect_count(ek_try) == 1 &&
2311 ek_adapter_opt_collect_type(ek_try) == T_OBJECT, "");
2312 ek_opt = ek_try;
2313 break;
2314 }
2315 // else downgrade to variable slot:
2316 ek_opt = _adapter_opt_collect_1_ref;
2317 break;
2318 case 2:
2319 ek_try = EntryKind(_adapter_opt_collect_2_S0_ref + argslot);
2320 if (ek_try < _adapter_opt_collect_LAST &&
2321 ek_adapter_opt_collect_slot(ek_try) == argslot) {
2322 assert(ek_adapter_opt_collect_count(ek_try) == 2 &&
2323 ek_adapter_opt_collect_type(ek_try) == T_OBJECT, "");
2324 ek_opt = ek_try;
2325 break;
2326 }
2327 // else downgrade to variable slot:
2328 ek_opt = _adapter_opt_collect_2_ref;
2329 break;
2330 default:
2331 goto throw_not_impl;
2332 break;
2333 }
2334 }
2335 break;
2336
2337 case _adapter_swap_args:
2338 case _adapter_rot_args:
2339 {
2340 int swap_slots = type2size[src];
2341 int src_slot = argslot;
2342 int dest_slot = vminfo;
2343 int rotate = (ek_orig == _adapter_swap_args) ? 0 : (src_slot > dest_slot) ? 1 : -1;
2344 switch (swap_slots) {
2345 case 1:
2346 ek_opt = (!rotate ? _adapter_opt_swap_1 :
2347 rotate > 0 ? _adapter_opt_rot_1_up : _adapter_opt_rot_1_down);
2348 break;
2349 case 2:
2350 ek_opt = (!rotate ? _adapter_opt_swap_2 :
2351 rotate > 0 ? _adapter_opt_rot_2_up : _adapter_opt_rot_2_down);
2352 break;
2353 default:
2354 goto throw_not_impl;
2355 break;
2356 }
2357 }
2358 break;
2359
2360 case _adapter_spread_args:
2361 {
2362 #ifdef TARGET_ARCH_NYI_6939861
2363 // ports before 6939861 supported only three kinds of spread ops
2364 if (!UseRicochetFrames) {
2365 int array_size = slots_pushed + 1;
2366 assert(array_size >= 0, "");
2367 vminfo = array_size;
2368 switch (array_size) {
2369 case 0: ek_opt = _adapter_opt_spread_0; break;
2370 case 1: ek_opt = _adapter_opt_spread_1; break;
2371 default: ek_opt = _adapter_opt_spread_more; break;
2372 }
2373 break;
2374 }
2375 #endif //TARGET_ARCH_NYI_6939861
2376 // vminfo will be the required length of the array
2377 int array_size = (slots_pushed + 1) / (type2size[dest] == 2 ? 2 : 1);
2378 vminfo = array_size;
2379 // general case
2380 switch (dest) {
2381 case T_BOOLEAN : // fall through to T_BYTE:
2382 case T_BYTE : ek_opt = _adapter_opt_spread_byte; break;
2383 case T_CHAR : ek_opt = _adapter_opt_spread_char; break;
2384 case T_SHORT : ek_opt = _adapter_opt_spread_short; break;
2385 case T_INT : ek_opt = _adapter_opt_spread_int; break;
2386 case T_LONG : ek_opt = _adapter_opt_spread_long; break;
2387 case T_FLOAT : ek_opt = _adapter_opt_spread_float; break;
2388 case T_DOUBLE : ek_opt = _adapter_opt_spread_double; break;
2389 case T_OBJECT : ek_opt = _adapter_opt_spread_ref; break;
2390 case T_VOID : if (array_size != 0) goto throw_not_impl;
2391 ek_opt = _adapter_opt_spread_ref; break;
2392 default : goto throw_not_impl;
2393 }
2394 assert(array_size == 0 || // it doesn't matter what the spreader is
2395 (ek_adapter_opt_spread_count(ek_opt) == -1 &&
2396 (ek_adapter_opt_spread_type(ek_opt) == dest ||
2397 (ek_adapter_opt_spread_type(ek_opt) == T_BYTE && dest == T_BOOLEAN))),
2398 err_msg("dest=%d ek_opt=%d", dest, ek_opt));
2399
2400 if (array_size <= 0) {
2401 // since the general case does not handle length 0, this case is required:
2402 ek_opt = _adapter_opt_spread_0;
2403 break;
2404 }
2405 if (dest == T_OBJECT) {
2406 ek_try = EntryKind(_adapter_opt_spread_1_ref - 1 + array_size);
2407 if (ek_try < _adapter_opt_spread_LAST &&
2408 ek_adapter_opt_spread_count(ek_try) == array_size) {
2409 assert(ek_adapter_opt_spread_type(ek_try) == dest, "");
2410 ek_opt = ek_try;
2411 break;
2412 }
2413 }
2414 break;
2415 }
2416 break;
2417
2418 case _adapter_collect_args:
2419 {
2420 assert(UseRicochetFrames, "else don't come here");
2421 int elem_slots = argument_slot_count(java_lang_invoke_MethodHandle::type(argument()));
2422 // vminfo will be the location to insert the return value
2423 vminfo = argslot;
2424 ensure_vmlayout_field(target, CHECK);
2425 ensure_vmlayout_field(argument, CHECK);
2426
2427 // general case:
2428 switch (dest) {
2429 default : if (!is_subword_type(dest)) goto throw_not_impl;
2430 // else fall through:
2431 case T_INT : ek_opt = _adapter_opt_collect_int; break;
2432 case T_LONG : ek_opt = _adapter_opt_collect_long; break;
2433 case T_FLOAT : ek_opt = _adapter_opt_collect_float; break;
2434 case T_DOUBLE : ek_opt = _adapter_opt_collect_double; break;
2435 case T_OBJECT : ek_opt = _adapter_opt_collect_ref; break;
2436 case T_VOID : ek_opt = _adapter_opt_collect_void; break;
2437 }
2438 assert(ek_adapter_opt_collect_slot(ek_opt) == -1 &&
2439 ek_adapter_opt_collect_count(ek_opt) == -1 &&
2440 (ek_adapter_opt_collect_type(ek_opt) == dest ||
2441 ek_adapter_opt_collect_type(ek_opt) == T_INT && is_subword_type(dest)),
2442 "");
2443
2444 if (dest == T_OBJECT && elem_slots == 1 && OptimizeMethodHandles) {
2445 // filter operation on a ref
2446 ek_try = EntryKind(_adapter_opt_filter_S0_ref + argslot);
2447 if (ek_try < _adapter_opt_collect_LAST &&
2448 ek_adapter_opt_collect_slot(ek_try) == argslot) {
2449 assert(ek_adapter_opt_collect_count(ek_try) == elem_slots &&
2450 ek_adapter_opt_collect_type(ek_try) == dest, "");
2451 ek_opt = ek_try;
2452 break;
2453 }
2454 ek_opt = _adapter_opt_collect_1_ref;
2455 break;
2456 }
2457
2458 if (dest == T_OBJECT && elem_slots == 2 && OptimizeMethodHandles) {
2459 // filter of two arguments
2460 ek_try = EntryKind(_adapter_opt_collect_2_S0_ref + argslot);
2461 if (ek_try < _adapter_opt_collect_LAST &&
2462 ek_adapter_opt_collect_slot(ek_try) == argslot) {
2463 assert(ek_adapter_opt_collect_count(ek_try) == elem_slots &&
2464 ek_adapter_opt_collect_type(ek_try) == dest, "");
2465 ek_opt = ek_try;
2466 break;
2467 }
2468 ek_opt = _adapter_opt_collect_2_ref;
2469 break;
2470 }
2471
2472 if (dest == T_OBJECT && OptimizeMethodHandles) {
2473 // try to use a fixed length adapter
2474 ek_try = EntryKind(_adapter_opt_collect_0_ref + elem_slots);
2475 if (ek_try < _adapter_opt_collect_LAST &&
2476 ek_adapter_opt_collect_count(ek_try) == elem_slots) {
2477 assert(ek_adapter_opt_collect_slot(ek_try) == -1 &&
2478 ek_adapter_opt_collect_type(ek_try) == dest, "");
2479 ek_opt = ek_try;
2480 break;
2481 }
2482 }
2483
2484 break;
2485 }
2486
2487 case _adapter_fold_args:
2488 {
2489 assert(UseRicochetFrames, "else don't come here");
2490 int elem_slots = argument_slot_count(java_lang_invoke_MethodHandle::type(argument()));
2491 // vminfo will be the location to insert the return value
2492 vminfo = argslot + elem_slots;
2493 ensure_vmlayout_field(target, CHECK);
2494 ensure_vmlayout_field(argument, CHECK);
2495
2496 switch (dest) {
2497 default : if (!is_subword_type(dest)) goto throw_not_impl;
2498 // else fall through:
2499 case T_INT : ek_opt = _adapter_opt_fold_int; break;
2500 case T_LONG : ek_opt = _adapter_opt_fold_long; break;
2501 case T_FLOAT : ek_opt = _adapter_opt_fold_float; break;
2502 case T_DOUBLE : ek_opt = _adapter_opt_fold_double; break;
2503 case T_OBJECT : ek_opt = _adapter_opt_fold_ref; break;
2504 case T_VOID : ek_opt = _adapter_opt_fold_void; break;
2505 }
2506 assert(ek_adapter_opt_collect_slot(ek_opt) == -1 &&
2507 ek_adapter_opt_collect_count(ek_opt) == -1 &&
2508 (ek_adapter_opt_collect_type(ek_opt) == dest ||
2509 ek_adapter_opt_collect_type(ek_opt) == T_INT && is_subword_type(dest)),
2510 "");
2511
2512 if (dest == T_OBJECT && elem_slots == 0 && OptimizeMethodHandles) {
2513 // if there are no args, just pretend it's a collect
2514 ek_opt = _adapter_opt_collect_0_ref;
2515 break;
2516 }
2517
2518 if (dest == T_OBJECT && OptimizeMethodHandles) {
2519 // try to use a fixed length adapter
2520 ek_try = EntryKind(_adapter_opt_fold_1_ref - 1 + elem_slots);
2521 if (ek_try < _adapter_opt_fold_LAST &&
2522 ek_adapter_opt_collect_count(ek_try) == elem_slots) {
2523 assert(ek_adapter_opt_collect_slot(ek_try) == -1 &&
2524 ek_adapter_opt_collect_type(ek_try) == dest, "");
2525 ek_opt = ek_try;
2526 break;
2527 }
2528 }
2529
2530 break;
2531 }
2532
2533 default:
2534 // should have failed much earlier; must be a missing case here
2535 assert(false, "incomplete switch");
2536 // and fall through:
2537
2538 throw_not_impl:
2539 if (err == NULL)
2540 err = "unknown adapter type";
2541 break;
2542 }
2543
2544 if (err == NULL && (vminfo & CONV_VMINFO_MASK) != vminfo) {
2545 // should not happen, since vminfo is used to encode arg/slot indexes < 255
2546 err = "vminfo overflow";
2547 }
2548
2549 if (err == NULL && !have_entry(ek_opt)) {
2550 err = "adapter stub for this kind of method handle is missing";
2551 }
2552
2553 if (err == NULL && ek_opt == ek_orig) {
2554 switch (ek_opt) {
2555 case _adapter_prim_to_prim:
2556 case _adapter_ref_to_prim:
2557 case _adapter_prim_to_ref:
2558 case _adapter_swap_args:
2559 case _adapter_rot_args:
2560 case _adapter_collect_args:
2561 case _adapter_fold_args:
2562 case _adapter_spread_args:
2563 // should be handled completely by optimized cases; see above
2564 err = "init_AdapterMethodHandle should not issue this";
2565 break;
2566 }
2567 }
2568
2569 if (err != NULL) {
2570 throw_InternalError_for_bad_conversion(conversion, err, THREAD);
2571 return;
2572 }
2573
2574 // Rebuild the conversion value; maybe parts of it were changed.
2575 jint new_conversion = adapter_conversion(conv_op, src, dest, stack_move, vminfo);
2576
2577 // Finalize the conversion field. (Note that it is final to Java code.)
2578 java_lang_invoke_AdapterMethodHandle::set_conversion(mh(), new_conversion);
2579
2580 // Done!
2581 java_lang_invoke_MethodHandle::set_vmentry(mh(), entry(ek_opt));
2582
2583 // There should be enough memory barriers on exit from native methods
2584 // to ensure that the MH is fully initialized to all threads before
2585 // Java code can publish it in global data structures.
2586 }
2587
2588 void MethodHandles::ensure_vmlayout_field(Handle target, TRAPS) {
2589 Handle mtype(THREAD, java_lang_invoke_MethodHandle::type(target()));
2590 Handle mtform(THREAD, java_lang_invoke_MethodType::form(mtype()));
2591 if (mtform.is_null()) { THROW(vmSymbols::java_lang_InternalError()); }
2592 if (java_lang_invoke_MethodTypeForm::vmlayout_offset_in_bytes() > 0) {
2593 if (java_lang_invoke_MethodTypeForm::vmlayout(mtform()) == NULL) {
2594 // fill it in
2595 Handle erased_mtype(THREAD, java_lang_invoke_MethodTypeForm::erasedType(mtform()));
2596 TempNewSymbol erased_signature
2597 = java_lang_invoke_MethodType::as_signature(erased_mtype(), /*intern:*/true, CHECK);
2598 methodOop cookie
2599 = SystemDictionary::find_method_handle_invoke(vmSymbols::invokeExact_name(),
2600 erased_signature,
2601 SystemDictionaryHandles::Object_klass(),
2602 THREAD);
2603 java_lang_invoke_MethodTypeForm::init_vmlayout(mtform(), cookie);
2604 }
2605 }
2606 }
2607
2608 #ifdef ASSERT
2609
2610 extern "C"
2611 void print_method_handle(oop mh);
2612
2613 static void stress_method_handle_walk_impl(Handle mh, TRAPS) {
2614 if (StressMethodHandleWalk) {
2615 // Exercise the MethodHandleWalk code in various ways and validate
2616 // the resulting method oop. Some of these produce output so they
2617 // are guarded under Verbose.
2618 ResourceMark rm;
2619 HandleMark hm;
2620 if (Verbose) {
2621 print_method_handle(mh());
2622 }
2623 TempNewSymbol name = SymbolTable::new_symbol("invoke", CHECK);
2624 Handle mt = java_lang_invoke_MethodHandle::type(mh());
2625 TempNewSymbol signature = java_lang_invoke_MethodType::as_signature(mt(), true, CHECK);
2626 MethodHandleCompiler mhc(mh, name, signature, 10000, false, CHECK);
2627 methodHandle m = mhc.compile(CHECK);
2628 if (Verbose) {
2629 m->print_codes();
2630 }
2631 InterpreterOopMap mask;
2632 OopMapCache::compute_one_oop_map(m, m->code_size() - 1, &mask);
2633 }
2634 }
2635
2636 static void stress_method_handle_walk(Handle mh, TRAPS) {
2637 stress_method_handle_walk_impl(mh, THREAD);
2638 if (HAS_PENDING_EXCEPTION) {
2639 oop ex = PENDING_EXCEPTION;
2640 CLEAR_PENDING_EXCEPTION;
2641 tty->print("StressMethodHandleWalk: ");
2642 java_lang_Throwable::print(ex, tty);
2643 tty->cr();
2644 }
2645 }
2646 #else
2647
2648 static void stress_method_handle_walk(Handle mh, TRAPS) {}
2649
2650 #endif
2651
2652 //
2653 // Here are the native methods on sun.invoke.MethodHandleImpl.
2654 // They are the private interface between this JVM and the HotSpot-specific
2655 // Java code that implements JSR 292 method handles.
2656 //
2657 // Note: We use a JVM_ENTRY macro to define each of these, for this is the way
2658 // that intrinsic (non-JNI) native methods are defined in HotSpot.
2659 //
2660
2661 // direct method handles for invokestatic or invokespecial
2662 // void init(DirectMethodHandle self, MemberName ref, boolean doDispatch, Class<?> caller);
2663 JVM_ENTRY(void, MHN_init_DMH(JNIEnv *env, jobject igcls, jobject mh_jh,
2664 jobject target_jh, jboolean do_dispatch, jobject caller_jh)) {
2665 ResourceMark rm; // for error messages
2666
2667 // This is the guy we are initializing:
2668 if (mh_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "self is null"); }
2669 Handle mh(THREAD, JNIHandles::resolve_non_null(mh_jh));
2670
2671 // Early returns out of this method leave the DMH in an unfinished state.
2672 assert(java_lang_invoke_MethodHandle::vmentry(mh()) == NULL, "must be safely null");
2673
2674 // which method are we really talking about?
2675 if (target_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "target is null"); }
2676 Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
2677 if (java_lang_invoke_MemberName::is_instance(target()) &&
2678 java_lang_invoke_MemberName::vmindex(target()) == VM_INDEX_UNINITIALIZED) {
2679 MethodHandles::resolve_MemberName(target, CHECK);
2680 }
2681
2682 KlassHandle receiver_limit; int decode_flags = 0;
2683 methodHandle m = MethodHandles::decode_method(target(), receiver_limit, decode_flags);
2684 if (m.is_null()) { THROW_MSG(vmSymbols::java_lang_InternalError(), "no such method"); }
2685
2686 // The trusted Java code that calls this method should already have performed
2687 // access checks on behalf of the given caller. But, we can verify this.
2688 if (VerifyMethodHandles && caller_jh != NULL) {
2689 KlassHandle caller(THREAD, java_lang_Class::as_klassOop(JNIHandles::resolve_non_null(caller_jh)));
2690 // If this were a bytecode, the first access check would be against
2691 // the "reference class" mentioned in the CONSTANT_Methodref.
2692 // We don't know at this point which class that was, and if we
2693 // check against m.method_holder we might get the wrong answer.
2694 // So we just make sure to handle this check when the resolution
2695 // happens, when we call resolve_MemberName.
2696 //
2697 // (A public class can inherit public members from private supers,
2698 // and it would be wrong to check access against the private super
2699 // if the original symbolic reference was against the public class.)
2700 //
2701 // If there were a bytecode, the next step would be to lookup the method
2702 // in the reference class, then then check the method's access bits.
2703 // Emulate LinkResolver::check_method_accessability.
2704 klassOop resolved_klass = m->method_holder();
2705 if (!Reflection::verify_field_access(caller->as_klassOop(),
2706 resolved_klass, resolved_klass,
2707 m->access_flags(),
2708 true)) {
2709 // %%% following cutout belongs in Reflection::verify_field_access?
2710 bool same_pm = Reflection::is_same_package_member(caller->as_klassOop(),
2711 resolved_klass, THREAD);
2712 if (!same_pm) {
2713 THROW_MSG(vmSymbols::java_lang_InternalError(), m->name_and_sig_as_C_string());
2714 }
2715 }
2716 }
2717
2718 MethodHandles::init_DirectMethodHandle(mh, m, (do_dispatch != JNI_FALSE), CHECK);
2719 stress_method_handle_walk(mh, CHECK);
2720 }
2721 JVM_END
2722
2723 // bound method handles
2724 JVM_ENTRY(void, MHN_init_BMH(JNIEnv *env, jobject igcls, jobject mh_jh,
2725 jobject target_jh, int argnum)) {
2726 ResourceMark rm; // for error messages
2727
2728 // This is the guy we are initializing:
2729 if (mh_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "self is null"); }
2730 Handle mh(THREAD, JNIHandles::resolve_non_null(mh_jh));
2731
2732 // Early returns out of this method leave the BMH in an unfinished state.
2733 assert(java_lang_invoke_MethodHandle::vmentry(mh()) == NULL, "must be safely null");
2734
2735 if (target_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "target is null"); }
2736 Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
2737
2738 if (!java_lang_invoke_MethodHandle::is_instance(target())) {
2739 // Target object is a reflective method. (%%% Do we need this alternate path?)
2740 Untested("init_BMH of non-MH");
2741 if (argnum != 0) { THROW(vmSymbols::java_lang_InternalError()); }
2742 KlassHandle receiver_limit; int decode_flags = 0;
2743 methodHandle m = MethodHandles::decode_method(target(), receiver_limit, decode_flags);
2744 MethodHandles::init_BoundMethodHandle_with_receiver(mh, m,
2745 receiver_limit,
2746 decode_flags,
2747 CHECK);
2748 } else {
2749 // Build a BMH on top of a DMH or another BMH:
2750 MethodHandles::init_BoundMethodHandle(mh, target, argnum, CHECK);
2751 }
2752 stress_method_handle_walk(mh, CHECK);
2753 }
2754 JVM_END
2755
2756 // adapter method handles
2757 JVM_ENTRY(void, MHN_init_AMH(JNIEnv *env, jobject igcls, jobject mh_jh,
2758 jobject target_jh, int argnum)) {
2759 // This is the guy we are initializing:
2760 if (mh_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "self is null"); }
2761 if (target_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "target is null"); }
2762 Handle mh(THREAD, JNIHandles::resolve_non_null(mh_jh));
2763 Handle target(THREAD, JNIHandles::resolve_non_null(target_jh));
2764
2765 // Early returns out of this method leave the AMH in an unfinished state.
2766 assert(java_lang_invoke_MethodHandle::vmentry(mh()) == NULL, "must be safely null");
2767
2768 MethodHandles::init_AdapterMethodHandle(mh, target, argnum, CHECK);
2769 stress_method_handle_walk(mh, CHECK);
2770 }
2771 JVM_END
2772
2773 // method type forms
2774 JVM_ENTRY(void, MHN_init_MT(JNIEnv *env, jobject igcls, jobject erased_jh)) {
2775 if (erased_jh == NULL) return;
2776 if (TraceMethodHandles) {
2777 tty->print("creating MethodType form ");
2778 if (WizardMode || Verbose) { // Warning: this calls Java code on the MH!
2779 // call Object.toString()
2780 Symbol* name = vmSymbols::toString_name();
2781 Symbol* sig = vmSymbols::void_string_signature();
2782 JavaCallArguments args(Handle(THREAD, JNIHandles::resolve_non_null(erased_jh)));
2783 JavaValue result(T_OBJECT);
2784 JavaCalls::call_virtual(&result, SystemDictionary::Object_klass(), name, sig,
2785 &args, CHECK);
2786 Handle str(THREAD, (oop)result.get_jobject());
2787 java_lang_String::print(str, tty);
2788 }
2789 tty->cr();
2790 }
2791 }
2792 JVM_END
2793
2794 // debugging and reflection
2795 JVM_ENTRY(jobject, MHN_getTarget(JNIEnv *env, jobject igcls, jobject mh_jh, jint format)) {
2796 Handle mh(THREAD, JNIHandles::resolve(mh_jh));
2797 if (!java_lang_invoke_MethodHandle::is_instance(mh())) {
2798 THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
2799 }
2800 oop target = MethodHandles::encode_target(mh, format, CHECK_NULL);
2801 return JNIHandles::make_local(THREAD, target);
2802 }
2803 JVM_END
2804
2805 JVM_ENTRY(jint, MHN_getConstant(JNIEnv *env, jobject igcls, jint which)) {
2806 switch (which) {
2807 case MethodHandles::GC_JVM_PUSH_LIMIT:
2808 guarantee(MethodHandlePushLimit >= 2 && MethodHandlePushLimit <= 0xFF,
2809 "MethodHandlePushLimit parameter must be in valid range");
2810 return MethodHandlePushLimit;
2811 case MethodHandles::GC_JVM_STACK_MOVE_UNIT:
2812 // return number of words per slot, signed according to stack direction
2813 return MethodHandles::stack_move_unit();
2814 case MethodHandles::GC_CONV_OP_IMPLEMENTED_MASK:
2815 return MethodHandles::adapter_conversion_ops_supported_mask();
2816 }
2817 return 0;
2818 }
2819 JVM_END
2820
2821 #ifndef PRODUCT
2822 #define EACH_NAMED_CON(template) \
2823 /* hold back this one until JDK stabilizes */ \
2824 /* template(MethodHandles,GC_JVM_PUSH_LIMIT) */ \
2825 /* hold back this one until JDK stabilizes */ \
2826 /* template(MethodHandles,GC_JVM_STACK_MOVE_UNIT) */ \
2827 template(MethodHandles,ETF_HANDLE_OR_METHOD_NAME) \
2828 template(MethodHandles,ETF_DIRECT_HANDLE) \
2829 template(MethodHandles,ETF_METHOD_NAME) \
2830 template(MethodHandles,ETF_REFLECT_METHOD) \
2831 template(java_lang_invoke_MemberName,MN_IS_METHOD) \
2832 template(java_lang_invoke_MemberName,MN_IS_CONSTRUCTOR) \
2833 template(java_lang_invoke_MemberName,MN_IS_FIELD) \
2834 template(java_lang_invoke_MemberName,MN_IS_TYPE) \
2835 template(java_lang_invoke_MemberName,MN_SEARCH_SUPERCLASSES) \
2836 template(java_lang_invoke_MemberName,MN_SEARCH_INTERFACES) \
2837 template(java_lang_invoke_MemberName,VM_INDEX_UNINITIALIZED) \
2838 template(java_lang_invoke_AdapterMethodHandle,OP_RETYPE_ONLY) \
2839 template(java_lang_invoke_AdapterMethodHandle,OP_RETYPE_RAW) \
2840 template(java_lang_invoke_AdapterMethodHandle,OP_CHECK_CAST) \
2841 template(java_lang_invoke_AdapterMethodHandle,OP_PRIM_TO_PRIM) \
2842 template(java_lang_invoke_AdapterMethodHandle,OP_REF_TO_PRIM) \
2843 template(java_lang_invoke_AdapterMethodHandle,OP_PRIM_TO_REF) \
2844 template(java_lang_invoke_AdapterMethodHandle,OP_SWAP_ARGS) \
2845 template(java_lang_invoke_AdapterMethodHandle,OP_ROT_ARGS) \
2846 template(java_lang_invoke_AdapterMethodHandle,OP_DUP_ARGS) \
2847 template(java_lang_invoke_AdapterMethodHandle,OP_DROP_ARGS) \
2848 template(java_lang_invoke_AdapterMethodHandle,OP_COLLECT_ARGS) \
2849 template(java_lang_invoke_AdapterMethodHandle,OP_SPREAD_ARGS) \
2850 /* hold back this one until JDK stabilizes */ \
2851 /*template(java_lang_invoke_AdapterMethodHandle,CONV_OP_LIMIT)*/ \
2852 template(java_lang_invoke_AdapterMethodHandle,CONV_OP_MASK) \
2853 template(java_lang_invoke_AdapterMethodHandle,CONV_VMINFO_MASK) \
2854 template(java_lang_invoke_AdapterMethodHandle,CONV_VMINFO_SHIFT) \
2855 template(java_lang_invoke_AdapterMethodHandle,CONV_OP_SHIFT) \
2856 template(java_lang_invoke_AdapterMethodHandle,CONV_DEST_TYPE_SHIFT) \
2857 template(java_lang_invoke_AdapterMethodHandle,CONV_SRC_TYPE_SHIFT) \
2858 template(java_lang_invoke_AdapterMethodHandle,CONV_STACK_MOVE_SHIFT) \
2859 template(java_lang_invoke_AdapterMethodHandle,CONV_STACK_MOVE_MASK) \
2860 /*end*/
2861
2862 #define ONE_PLUS(scope,value) 1+
2863 static const int con_value_count = EACH_NAMED_CON(ONE_PLUS) 0;
2864 #define VALUE_COMMA(scope,value) scope::value,
2865 static const int con_values[con_value_count+1] = { EACH_NAMED_CON(VALUE_COMMA) 0 };
2866 #define STRING_NULL(scope,value) #value "\0"
2867 static const char con_names[] = { EACH_NAMED_CON(STRING_NULL) };
2868
2869 #undef ONE_PLUS
2870 #undef VALUE_COMMA
2871 #undef STRING_NULL
2872 #undef EACH_NAMED_CON
2873 #endif
2874
2875 JVM_ENTRY(jint, MHN_getNamedCon(JNIEnv *env, jobject igcls, jint which, jobjectArray box_jh)) {
2876 #ifndef PRODUCT
2877 if (which >= 0 && which < con_value_count) {
2878 int con = con_values[which];
2879 objArrayHandle box(THREAD, (objArrayOop) JNIHandles::resolve(box_jh));
2880 if (box.not_null() && box->klass() == Universe::objectArrayKlassObj() && box->length() > 0) {
2881 const char* str = &con_names[0];
2882 for (int i = 0; i < which; i++)
2883 str += strlen(str) + 1; // skip name and null
2884 oop name = java_lang_String::create_oop_from_str(str, CHECK_0); // possible safepoint
2885 box->obj_at_put(0, name);
2886 }
2887 return con;
2888 }
2889 #endif
2890 return 0;
2891 }
2892 JVM_END
2893
2894 // void init(MemberName self, AccessibleObject ref)
2895 JVM_ENTRY(void, MHN_init_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jobject target_jh)) {
2896 if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
2897 if (target_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "target is null"); }
2898 Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
2899 oop target_oop = JNIHandles::resolve_non_null(target_jh);
2900 MethodHandles::init_MemberName(mname(), target_oop);
2901 }
2902 JVM_END
2903
2904 // void expand(MemberName self)
2905 JVM_ENTRY(void, MHN_expand_Mem(JNIEnv *env, jobject igcls, jobject mname_jh)) {
2906 if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
2907 Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
2908 MethodHandles::expand_MemberName(mname, 0, CHECK);
2909 }
2910 JVM_END
2911
2912 // void resolve(MemberName self, Class<?> caller)
2913 JVM_ENTRY(void, MHN_resolve_Mem(JNIEnv *env, jobject igcls, jobject mname_jh, jclass caller_jh)) {
2914 if (mname_jh == NULL) { THROW_MSG(vmSymbols::java_lang_InternalError(), "mname is null"); }
2915 Handle mname(THREAD, JNIHandles::resolve_non_null(mname_jh));
2916
2917 // The trusted Java code that calls this method should already have performed
2918 // access checks on behalf of the given caller. But, we can verify this.
2919 if (VerifyMethodHandles && caller_jh != NULL) {
2920 klassOop reference_klass = java_lang_Class::as_klassOop(java_lang_invoke_MemberName::clazz(mname()));
2921 if (reference_klass != NULL) {
2922 // Emulate LinkResolver::check_klass_accessability.
2923 klassOop caller = java_lang_Class::as_klassOop(JNIHandles::resolve_non_null(caller_jh));
2924 if (!Reflection::verify_class_access(caller,
2925 reference_klass,
2926 true)) {
2927 THROW_MSG(vmSymbols::java_lang_InternalError(), Klass::cast(reference_klass)->external_name());
2928 }
2929 }
2930 }
2931
2932 MethodHandles::resolve_MemberName(mname, CHECK);
2933 }
2934 JVM_END
2935
2936 // static native int getMembers(Class<?> defc, String matchName, String matchSig,
2937 // int matchFlags, Class<?> caller, int skip, MemberName[] results);
2938 JVM_ENTRY(jint, MHN_getMembers(JNIEnv *env, jobject igcls,
2939 jclass clazz_jh, jstring name_jh, jstring sig_jh,
2940 int mflags, jclass caller_jh, jint skip, jobjectArray results_jh)) {
2941 if (clazz_jh == NULL || results_jh == NULL) return -1;
2942 KlassHandle k(THREAD, java_lang_Class::as_klassOop(JNIHandles::resolve_non_null(clazz_jh)));
2943
2944 objArrayHandle results(THREAD, (objArrayOop) JNIHandles::resolve(results_jh));
2945 if (results.is_null() || !results->is_objArray()) return -1;
2946
2947 TempNewSymbol name = NULL;
2948 TempNewSymbol sig = NULL;
2949 if (name_jh != NULL) {
2950 name = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(name_jh));
2951 if (name == NULL) return 0; // a match is not possible
2952 }
2953 if (sig_jh != NULL) {
2954 sig = java_lang_String::as_symbol_or_null(JNIHandles::resolve_non_null(sig_jh));
2955 if (sig == NULL) return 0; // a match is not possible
2956 }
2957
2958 KlassHandle caller;
2959 if (caller_jh != NULL) {
2960 oop caller_oop = JNIHandles::resolve_non_null(caller_jh);
2961 if (!java_lang_Class::is_instance(caller_oop)) return -1;
2962 caller = KlassHandle(THREAD, java_lang_Class::as_klassOop(caller_oop));
2963 }
2964
2965 if (name != NULL && sig != NULL && results.not_null()) {
2966 // try a direct resolve
2967 // %%% TO DO
2968 }
2969
2970 int res = MethodHandles::find_MemberNames(k(), name, sig, mflags,
2971 caller(), skip, results());
2972 // TO DO: expand at least some of the MemberNames, to avoid massive callbacks
2973 return res;
2974 }
2975 JVM_END
2976
2977 JVM_ENTRY(jobject, MH_invoke_UOE(JNIEnv *env, jobject igmh, jobjectArray igargs)) {
2978 TempNewSymbol UOE_name = SymbolTable::new_symbol("java/lang/UnsupportedOperationException", CHECK_NULL);
2979 THROW_MSG_NULL(UOE_name, "MethodHandle.invoke cannot be invoked reflectively");
2980 return NULL;
2981 }
2982 JVM_END
2983
2984 JVM_ENTRY(jobject, MH_invokeExact_UOE(JNIEnv *env, jobject igmh, jobjectArray igargs)) {
2985 TempNewSymbol UOE_name = SymbolTable::new_symbol("java/lang/UnsupportedOperationException", CHECK_NULL);
2986 THROW_MSG_NULL(UOE_name, "MethodHandle.invokeExact cannot be invoked reflectively");
2987 return NULL;
2988 }
2989 JVM_END
2990
2991
2992 /// JVM_RegisterMethodHandleMethods
2993
2994 #define LANG "Ljava/lang/"
2995 #define JLINV "Ljava/lang/invoke/"
2996
2997 #define OBJ LANG"Object;"
2998 #define CLS LANG"Class;"
2999 #define STRG LANG"String;"
3000 #define MT JLINV"MethodType;"
3001 #define MH JLINV"MethodHandle;"
3002 #define MEM JLINV"MemberName;"
3003 #define AMH JLINV"AdapterMethodHandle;"
3004 #define BMH JLINV"BoundMethodHandle;"
3005 #define DMH JLINV"DirectMethodHandle;"
3006
3007 #define CC (char*) /*cast a literal from (const char*)*/
3008 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
3009
3010 // These are the native methods on sun.invoke.MethodHandleNatives.
3011 static JNINativeMethod methods[] = {
3012 // void init(MemberName self, AccessibleObject ref)
3013 {CC"init", CC"("AMH""MH"I)V", FN_PTR(MHN_init_AMH)},
3014 {CC"init", CC"("BMH""OBJ"I)V", FN_PTR(MHN_init_BMH)},
3015 {CC"init", CC"("DMH""OBJ"Z"CLS")V", FN_PTR(MHN_init_DMH)},
3016 {CC"init", CC"("MT")V", FN_PTR(MHN_init_MT)},
3017 {CC"init", CC"("MEM""OBJ")V", FN_PTR(MHN_init_Mem)},
3018 {CC"expand", CC"("MEM")V", FN_PTR(MHN_expand_Mem)},
3019 {CC"resolve", CC"("MEM""CLS")V", FN_PTR(MHN_resolve_Mem)},
3020 {CC"getTarget", CC"("MH"I)"OBJ, FN_PTR(MHN_getTarget)},
3021 {CC"getConstant", CC"(I)I", FN_PTR(MHN_getConstant)},
3022 // static native int getNamedCon(int which, Object[] name)
3023 {CC"getNamedCon", CC"(I["OBJ")I", FN_PTR(MHN_getNamedCon)},
3024 // static native int getMembers(Class<?> defc, String matchName, String matchSig,
3025 // int matchFlags, Class<?> caller, int skip, MemberName[] results);
3026 {CC"getMembers", CC"("CLS""STRG""STRG"I"CLS"I["MEM")I", FN_PTR(MHN_getMembers)}
3027 };
3028
3029 static JNINativeMethod invoke_methods[] = {
3030 // void init(MemberName self, AccessibleObject ref)
3031 {CC"invoke", CC"(["OBJ")"OBJ, FN_PTR(MH_invoke_UOE)},
3032 {CC"invokeExact", CC"(["OBJ")"OBJ, FN_PTR(MH_invokeExact_UOE)}
3033 };
3034
3035 // This one function is exported, used by NativeLookup.
3036
3037 JVM_ENTRY(void, JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass MHN_class)) {
3038 assert(MethodHandles::spot_check_entry_names(), "entry enum is OK");
3039
3040 if (!EnableInvokeDynamic) {
3041 warning("JSR 292 is disabled in this JVM. Use -XX:+UnlockDiagnosticVMOptions -XX:+EnableInvokeDynamic to enable.");
3042 return; // bind nothing
3043 }
3044
3045 bool enable_MH = true;
3046
3047 {
3048 ThreadToNativeFromVM ttnfv(thread);
3049
3050 int status = env->RegisterNatives(MHN_class, methods, sizeof(methods)/sizeof(JNINativeMethod));
3051 if (!env->ExceptionOccurred()) {
3052 const char* L_MH_name = (JLINV "MethodHandle");
3053 const char* MH_name = L_MH_name+1;
3054 jclass MH_class = env->FindClass(MH_name);
3055 status = env->RegisterNatives(MH_class, invoke_methods, sizeof(invoke_methods)/sizeof(JNINativeMethod));
3056 }
3057 if (env->ExceptionOccurred()) {
3058 MethodHandles::set_enabled(false);
3059 warning("JSR 292 method handle code is mismatched to this JVM. Disabling support.");
3060 enable_MH = false;
3061 env->ExceptionClear();
3062 }
3063 }
3064
3065 if (enable_MH) {
3066 KlassHandle MHN_klass = SystemDictionaryHandles::MethodHandleNatives_klass();
3067 if (MHN_klass.not_null()) {
3068 TempNewSymbol raiseException_name = SymbolTable::new_symbol("raiseException", CHECK);
3069 TempNewSymbol raiseException_sig = SymbolTable::new_symbol("(ILjava/lang/Object;Ljava/lang/Object;)V", CHECK);
3070 methodOop raiseException_method = instanceKlass::cast(MHN_klass->as_klassOop())
3071 ->find_method(raiseException_name, raiseException_sig);
3072 if (raiseException_method != NULL && raiseException_method->is_static()) {
3073 MethodHandles::set_raise_exception_method(raiseException_method);
3074 } else {
3075 warning("JSR 292 method handle code is mismatched to this JVM. Disabling support.");
3076 enable_MH = false;
3077 }
3078 } else {
3079 enable_MH = false;
3080 }
3081 }
3082
3083 if (enable_MH) {
3084 MethodHandles::generate_adapters();
3085 MethodHandles::set_enabled(true);
3086 }
3087 }
3088 JVM_END