1 /*
2 * Copyright (c) 1997, 2020, 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/systemDictionary.hpp"
27 #include "classfile/vmSymbols.hpp"
28 #include "code/nmethod.hpp"
29 #include "compiler/compilationPolicy.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "interpreter/interpreter.hpp"
32 #include "interpreter/linkResolver.hpp"
33 #include "memory/universe.hpp"
34 #include "oops/method.inline.hpp"
35 #include "oops/oop.inline.hpp"
36 #include "prims/jniCheck.hpp"
37 #include "runtime/handles.inline.hpp"
38 #include "runtime/interfaceSupport.inline.hpp"
39 #include "runtime/javaCalls.hpp"
40 #include "runtime/jniHandles.inline.hpp"
41 #include "runtime/mutexLocker.hpp"
42 #include "runtime/os.inline.hpp"
43 #include "runtime/sharedRuntime.hpp"
44 #include "runtime/signature.hpp"
45 #include "runtime/stubRoutines.hpp"
46 #include "runtime/thread.inline.hpp"
47
48 // -----------------------------------------------------
49 // Implementation of JavaCallWrapper
50
51 JavaCallWrapper::JavaCallWrapper(const methodHandle& callee_method, Handle receiver, JavaValue* result, TRAPS) {
52 JavaThread* thread = (JavaThread *)THREAD;
53 bool clear_pending_exception = true;
54
55 guarantee(thread->is_Java_thread(), "crucial check - the VM thread cannot and must not escape to Java code");
56 assert(!thread->owns_locks(), "must release all locks when leaving VM");
57 guarantee(thread->can_call_java(), "cannot make java calls from the native compiler");
58 _result = result;
59
60 // Allocate handle block for Java code. This must be done before we change thread_state to _thread_in_Java_or_stub,
61 // since it can potentially block.
62 JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(thread);
63
64 // After this, we are official in JavaCode. This needs to be done before we change any of the thread local
65 // info, since we cannot find oops before the new information is set up completely.
66 ThreadStateTransition::transition(thread, _thread_in_vm, _thread_in_Java);
67
68 // Make sure that we handle asynchronous stops and suspends _before_ we clear all thread state
69 // in JavaCallWrapper::JavaCallWrapper(). This way, we can decide if we need to do any pd actions
70 // to prepare for stop/suspend (flush register windows on sparcs, cache sp, or other state).
71 if (thread->has_special_runtime_exit_condition()) {
72 thread->handle_special_runtime_exit_condition();
73 if (HAS_PENDING_EXCEPTION) {
74 clear_pending_exception = false;
75 }
76 }
77
78
79 // Make sure to set the oop's after the thread transition - since we can block there. No one is GC'ing
80 // the JavaCallWrapper before the entry frame is on the stack.
81 _callee_method = callee_method();
82 _receiver = receiver();
83
84 #ifdef CHECK_UNHANDLED_OOPS
85 THREAD->allow_unhandled_oop(&_receiver);
86 #endif // CHECK_UNHANDLED_OOPS
87
88 _thread = (JavaThread *)thread;
89 _handles = _thread->active_handles(); // save previous handle block & Java frame linkage
90
91 // For the profiler, the last_Java_frame information in thread must always be in
92 // legal state. We have no last Java frame if last_Java_sp == NULL so
93 // the valid transition is to clear _last_Java_sp and then reset the rest of
94 // the (platform specific) state.
95
96 _anchor.copy(_thread->frame_anchor());
97 _thread->frame_anchor()->clear();
98
99 debug_only(_thread->inc_java_call_counter());
100 _thread->set_active_handles(new_handles); // install new handle block and reset Java frame linkage
101
102 assert (_thread->thread_state() != _thread_in_native, "cannot set native pc to NULL");
103
104 // clear any pending exception in thread (native calls start with no exception pending)
105 if(clear_pending_exception) {
106 _thread->clear_pending_exception();
107 }
108
109 if (_anchor.last_Java_sp() == NULL) {
110 _thread->record_base_of_stack_pointer();
111 }
112 }
113
114
115 JavaCallWrapper::~JavaCallWrapper() {
116 assert(_thread == JavaThread::current(), "must still be the same thread");
117
118 // restore previous handle block & Java frame linkage
119 JNIHandleBlock *_old_handles = _thread->active_handles();
120 _thread->set_active_handles(_handles);
121
122 _thread->frame_anchor()->zap();
123
124 debug_only(_thread->dec_java_call_counter());
125
126 if (_anchor.last_Java_sp() == NULL) {
127 _thread->set_base_of_stack_pointer(NULL);
128 }
129
130
131 // Old thread-local info. has been restored. We are not back in the VM.
132 ThreadStateTransition::transition_from_java(_thread, _thread_in_vm);
133
134 // State has been restored now make the anchor frame visible for the profiler.
135 // Do this after the transition because this allows us to put an assert
136 // the Java->vm transition which checks to see that stack is not walkable
137 // on sparc/ia64 which will catch violations of the reseting of last_Java_frame
138 // invariants (i.e. _flags always cleared on return to Java)
139
140 _thread->frame_anchor()->copy(&_anchor);
141
142 // Release handles after we are marked as being inside the VM again, since this
143 // operation might block
144 JNIHandleBlock::release_block(_old_handles, _thread);
145 }
146
147
148 void JavaCallWrapper::oops_do(OopClosure* f) {
149 f->do_oop((oop*)&_receiver);
150 handles()->oops_do(f);
151 }
152
153
154 // Helper methods
155 static BasicType runtime_type_from(JavaValue* result) {
156 switch (result->get_type()) {
157 case T_BOOLEAN: // fall through
158 case T_CHAR : // fall through
159 case T_SHORT : // fall through
160 case T_INT : // fall through
161 #ifndef _LP64
162 case T_OBJECT : // fall through
163 case T_ARRAY : // fall through
164 #endif
165 case T_BYTE : // fall through
166 case T_VOID : return T_INT;
167 case T_LONG : return T_LONG;
168 case T_FLOAT : return T_FLOAT;
169 case T_DOUBLE : return T_DOUBLE;
170 #ifdef _LP64
171 case T_ARRAY : // fall through
172 case T_OBJECT: return T_OBJECT;
173 #endif
174 default:
175 ShouldNotReachHere();
176 return T_ILLEGAL;
177 }
178 }
179
180 // ============ Virtual calls ============
181
182 void JavaCalls::call_virtual(JavaValue* result, Klass* spec_klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
183 CallInfo callinfo;
184 Handle receiver = args->receiver();
185 Klass* recvrKlass = receiver.is_null() ? (Klass*)NULL : receiver->klass();
186 LinkInfo link_info(spec_klass, name, signature);
187 LinkResolver::resolve_virtual_call(
188 callinfo, receiver, recvrKlass, link_info, true, CHECK);
189 methodHandle method(THREAD, callinfo.selected_method());
190 assert(method.not_null(), "should have thrown exception");
191
192 // Invoke the method
193 JavaCalls::call(result, method, args, CHECK);
194 }
195
196
197 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, Klass* spec_klass, Symbol* name, Symbol* signature, TRAPS) {
198 JavaCallArguments args(receiver);
199 call_virtual(result, spec_klass, name, signature, &args, CHECK);
200 }
201
202
203 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, Klass* spec_klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
204 JavaCallArguments args(receiver);
205 args.push_oop(arg1);
206 call_virtual(result, spec_klass, name, signature, &args, CHECK);
207 }
208
209
210
211 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, Klass* spec_klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
212 JavaCallArguments args(receiver);
213 args.push_oop(arg1);
214 args.push_oop(arg2);
215 call_virtual(result, spec_klass, name, signature, &args, CHECK);
216 }
217
218
219 // ============ Special calls ============
220
221 void JavaCalls::call_special(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
222 CallInfo callinfo;
223 LinkInfo link_info(klass, name, signature);
224 LinkResolver::resolve_special_call(callinfo, args->receiver(), link_info, CHECK);
225 methodHandle method(THREAD, callinfo.selected_method());
226 assert(method.not_null(), "should have thrown exception");
227
228 // Invoke the method
229 JavaCalls::call(result, method, args, CHECK);
230 }
231
232
233 void JavaCalls::call_special(JavaValue* result, Handle receiver, Klass* klass, Symbol* name, Symbol* signature, TRAPS) {
234 JavaCallArguments args(receiver);
235 call_special(result, klass, name, signature, &args, CHECK);
236 }
237
238
239 void JavaCalls::call_special(JavaValue* result, Handle receiver, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
240 JavaCallArguments args(receiver);
241 args.push_oop(arg1);
242 call_special(result, klass, name, signature, &args, CHECK);
243 }
244
245
246 void JavaCalls::call_special(JavaValue* result, Handle receiver, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
247 JavaCallArguments args(receiver);
248 args.push_oop(arg1);
249 args.push_oop(arg2);
250 call_special(result, klass, name, signature, &args, CHECK);
251 }
252
253
254 // ============ Static calls ============
255
256 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
257 CallInfo callinfo;
258 LinkInfo link_info(klass, name, signature);
259 LinkResolver::resolve_static_call(callinfo, link_info, true, CHECK);
260 methodHandle method(THREAD, callinfo.selected_method());
261 assert(method.not_null(), "should have thrown exception");
262
263 // Invoke the method
264 JavaCalls::call(result, method, args, CHECK);
265 }
266
267
268 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, TRAPS) {
269 JavaCallArguments args;
270 call_static(result, klass, name, signature, &args, CHECK);
271 }
272
273
274 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
275 JavaCallArguments args(arg1);
276 call_static(result, klass, name, signature, &args, CHECK);
277 }
278
279
280 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
281 JavaCallArguments args;
282 args.push_oop(arg1);
283 args.push_oop(arg2);
284 call_static(result, klass, name, signature, &args, CHECK);
285 }
286
287
288 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, Handle arg3, TRAPS) {
289 JavaCallArguments args;
290 args.push_oop(arg1);
291 args.push_oop(arg2);
292 args.push_oop(arg3);
293 call_static(result, klass, name, signature, &args, CHECK);
294 }
295
296 // ============ allocate and initialize new object instance ============
297
298 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, JavaCallArguments* args, TRAPS) {
299 klass->initialize(CHECK_NH); // Quick no-op if already initialized.
300 Handle obj = klass->allocate_instance_handle(CHECK_NH);
301 JavaValue void_result(T_VOID);
302 args->set_receiver(obj); // inserts <obj> as the first argument.
303 JavaCalls::call_special(&void_result, klass,
304 vmSymbols::object_initializer_name(),
305 constructor_signature, args, CHECK_NH);
306 // Already returned a Null Handle if any exception is pending.
307 return obj;
308 }
309
310 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, TRAPS) {
311 JavaCallArguments args;
312 return JavaCalls::construct_new_instance(klass, constructor_signature, &args, THREAD);
313 }
314
315 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, Handle arg1, TRAPS) {
316 JavaCallArguments args;
317 args.push_oop(arg1);
318 return JavaCalls::construct_new_instance(klass, constructor_signature, &args, THREAD);
319 }
320
321 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, Handle arg1, Handle arg2, TRAPS) {
322 JavaCallArguments args;
323 args.push_oop(arg1);
324 args.push_oop(arg2);
325 return JavaCalls::construct_new_instance(klass, constructor_signature, &args, THREAD);
326 }
327
328 // -------------------------------------------------
329 // Implementation of JavaCalls (low level)
330
331
332 void JavaCalls::call(JavaValue* result, const methodHandle& method, JavaCallArguments* args, TRAPS) {
333 // Check if we need to wrap a potential OS exception handler around thread
334 // This is used for e.g. Win32 structured exception handlers
335 assert(THREAD->is_Java_thread(), "only JavaThreads can make JavaCalls");
336 // Need to wrap each and every time, since there might be native code down the
337 // stack that has installed its own exception handlers
338 os::os_exception_wrapper(call_helper, result, method, args, THREAD);
339 }
340
341 void JavaCalls::call_helper(JavaValue* result, const methodHandle& method, JavaCallArguments* args, TRAPS) {
342
343 JavaThread* thread = (JavaThread*)THREAD;
344 assert(thread->is_Java_thread(), "must be called by a java thread");
345 assert(method.not_null(), "must have a method to call");
346 assert(!SafepointSynchronize::is_at_safepoint(), "call to Java code during VM operation");
347 assert(!thread->handle_area()->no_handle_mark_active(), "cannot call out to Java here");
348
349 #if INCLUDE_JVMCI
350 // Gets the nmethod (if any) that should be called instead of normal target
351 nmethod* alternative_target = args->alternative_target();
352 if (alternative_target == NULL) {
353 #endif
354 // Verify the arguments
355
356 if (CheckJNICalls) {
357 args->verify(method, result->get_type());
358 }
359 else debug_only(args->verify(method, result->get_type()));
360 #if INCLUDE_JVMCI
361 }
362 #else
363
364 // Ignore call if method is empty
365 if (method->is_empty_method()) {
366 assert(result->get_type() == T_VOID, "an empty method must return a void value");
367 return;
368 }
369 #endif
370
371 #ifdef ASSERT
372 { InstanceKlass* holder = method->method_holder();
373 // A klass might not be initialized since JavaCall's might be used during the executing of
374 // the <clinit>. For example, a Thread.start might start executing on an object that is
375 // not fully initialized! (bad Java programming style)
376 assert(holder->is_linked(), "rewriting must have taken place");
377 }
378 #endif
379
380 CompilationPolicy::compile_if_required(method, CHECK);
381
382 // Since the call stub sets up like the interpreter we call the from_interpreted_entry
383 // so we can go compiled via a i2c. Otherwise initial entry method will always
384 // run interpreted.
385 address entry_point = method->from_interpreted_entry();
386 if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
387 entry_point = method->interpreter_entry();
388 }
389
390 // Figure out if the result value is an oop or not (Note: This is a different value
391 // than result_type. result_type will be T_INT of oops. (it is about size)
392 BasicType result_type = runtime_type_from(result);
393 bool oop_result_flag = is_reference_type(result->get_type());
394
395 // Find receiver
396 Handle receiver = (!method->is_static()) ? args->receiver() : Handle();
397
398 // When we reenter Java, we need to reenable the reserved/yellow zone which
399 // might already be disabled when we are in VM.
400 if (!thread->stack_guards_enabled()) {
401 thread->reguard_stack();
402 }
403
404 // Check that there are shadow pages available before changing thread state
405 // to Java. Calculate current_stack_pointer here to make sure
406 // stack_shadow_pages_available() and bang_stack_shadow_pages() use the same sp.
407 address sp = os::current_stack_pointer();
408 if (!os::stack_shadow_pages_available(THREAD, method, sp)) {
409 // Throw stack overflow exception with preinitialized exception.
410 Exceptions::throw_stack_overflow_exception(THREAD, __FILE__, __LINE__, method);
411 return;
412 } else {
413 // Touch pages checked if the OS needs them to be touched to be mapped.
414 os::map_stack_shadow_pages(sp);
415 }
416
417 #if INCLUDE_JVMCI
418 if (alternative_target != NULL) {
419 if (alternative_target->is_alive() && !alternative_target->is_unloading()) {
420 thread->set_jvmci_alternate_call_target(alternative_target->verified_entry_point());
421 entry_point = method->adapter()->get_i2c_entry();
422 } else {
423 THROW(vmSymbols::jdk_vm_ci_code_InvalidInstalledCodeException());
424 }
425 }
426 #endif
427
428 // do call
429 { JavaCallWrapper link(method, receiver, result, CHECK);
430 { HandleMark hm(thread); // HandleMark used by HandleMarkCleaner
431
432 // NOTE: if we move the computation of the result_val_address inside
433 // the call to call_stub, the optimizer produces wrong code.
434 intptr_t* result_val_address = (intptr_t*)(result->get_value_addr());
435 intptr_t* parameter_address = args->parameters();
436
437 StubRoutines::call_stub()(
438 (address)&link,
439 // (intptr_t*)&(result->_value), // see NOTE above (compiler problem)
440 result_val_address, // see NOTE above (compiler problem)
441 result_type,
442 method(),
443 entry_point,
444 parameter_address,
445 args->size_of_parameters(),
446 CHECK
447 );
448
449 result = link.result(); // circumvent MS C++ 5.0 compiler bug (result is clobbered across call)
450 // Preserve oop return value across possible gc points
451 if (oop_result_flag) {
452 thread->set_vm_result((oop) result->get_jobject());
453 }
454 }
455 } // Exit JavaCallWrapper (can block - potential return oop must be preserved)
456
457 // Check if a thread stop or suspend should be executed
458 // The following assert was not realistic. Thread.stop can set that bit at any moment.
459 //assert(!thread->has_special_runtime_exit_condition(), "no async. exceptions should be installed");
460
461 // Restore possible oop return
462 if (oop_result_flag) {
463 result->set_jobject(cast_from_oop<jobject>(thread->vm_result()));
464 thread->set_vm_result(NULL);
465 }
466 }
467
468
469 //--------------------------------------------------------------------------------------
470 // Implementation of JavaCallArguments
471
472 inline bool is_value_state_indirect_oop(uint state) {
473 assert(state != JavaCallArguments::value_state_oop,
474 "Checking for handles after removal");
475 assert(state < JavaCallArguments::value_state_limit,
476 "Invalid value state %u", state);
477 return state != JavaCallArguments::value_state_primitive;
478 }
479
480 inline oop resolve_indirect_oop(intptr_t value, uint state) {
481 switch (state) {
482 case JavaCallArguments::value_state_handle:
483 {
484 oop* ptr = reinterpret_cast<oop*>(value);
485 return Handle::raw_resolve(ptr);
486 }
487
488 case JavaCallArguments::value_state_jobject:
489 {
490 jobject obj = reinterpret_cast<jobject>(value);
491 return JNIHandles::resolve(obj);
492 }
493
494 default:
495 ShouldNotReachHere();
496 return NULL;
497 }
498 }
499
500 intptr_t* JavaCallArguments::parameters() {
501 // First convert all handles to oops
502 for(int i = 0; i < _size; i++) {
503 uint state = _value_state[i];
504 assert(state != value_state_oop, "Multiple handle conversions");
505 if (is_value_state_indirect_oop(state)) {
506 oop obj = resolve_indirect_oop(_value[i], state);
507 _value[i] = cast_from_oop<intptr_t>(obj);
508 _value_state[i] = value_state_oop;
509 }
510 }
511 // Return argument vector
512 return _value;
513 }
514
515
516 class SignatureChekker : public SignatureIterator {
517 private:
518 int _pos;
519 BasicType _return_type;
520 u_char* _value_state;
521 intptr_t* _value;
522
523 public:
524 SignatureChekker(Symbol* signature,
525 BasicType return_type,
526 bool is_static,
527 u_char* value_state,
528 intptr_t* value) :
529 SignatureIterator(signature),
530 _pos(0),
531 _return_type(return_type),
532 _value_state(value_state),
533 _value(value)
534 {
535 if (!is_static) {
536 check_value(true); // Receiver must be an oop
537 }
538 do_parameters_on(this);
539 check_return_type(return_type);
540 }
541
542 private:
543 void check_value(bool is_reference) {
544 uint state = _value_state[_pos++];
545 if (is_reference) {
546 guarantee(is_value_state_indirect_oop(state),
547 "signature does not match pushed arguments: %u at %d",
548 state, _pos - 1);
549 } else {
550 guarantee(state == JavaCallArguments::value_state_primitive,
551 "signature does not match pushed arguments: %u at %d",
552 state, _pos - 1);
553 }
554 }
555
556 void check_return_type(BasicType t) {
557 guarantee(t == _return_type, "return type does not match");
558 }
559
560 void check_single_word() {
561 check_value(false);
562 }
563
564 void check_double_word() {
565 check_value(false);
566 check_value(false);
567 }
568
569 void check_reference() {
570 intptr_t v = _value[_pos];
571 if (v != 0) {
572 // v is a "handle" referring to an oop, cast to integral type.
573 // There shouldn't be any handles in very low memory.
574 guarantee((size_t)v >= (size_t)os::vm_page_size(),
575 "Bad JNI oop argument %d: " PTR_FORMAT, _pos, v);
576 // Verify the pointee.
577 oop vv = resolve_indirect_oop(v, _value_state[_pos]);
578 guarantee(oopDesc::is_oop_or_null(vv, true),
579 "Bad JNI oop argument %d: " PTR_FORMAT " -> " PTR_FORMAT,
580 _pos, v, p2i(vv));
581 }
582
583 check_value(true); // Verify value state.
584 }
585
586 friend class SignatureIterator; // so do_parameters_on can call do_type
587 void do_type(BasicType type) {
588 switch (type) {
589 case T_BYTE:
590 case T_BOOLEAN:
591 case T_CHAR:
592 case T_SHORT:
593 case T_INT:
594 case T_FLOAT: // this one also
595 check_single_word(); break;
596 case T_LONG:
597 case T_DOUBLE:
598 check_double_word(); break;
599 case T_ARRAY:
600 case T_OBJECT:
601 check_reference(); break;
602 default:
603 ShouldNotReachHere();
604 }
605 }
606 };
607
608
609 void JavaCallArguments::verify(const methodHandle& method, BasicType return_type) {
610 guarantee(method->size_of_parameters() == size_of_parameters(), "wrong no. of arguments pushed");
611
612 // Treat T_OBJECT and T_ARRAY as the same
613 if (is_reference_type(return_type)) return_type = T_OBJECT;
614
615 // Check that oop information is correct
616 Symbol* signature = method->signature();
617
618 SignatureChekker sc(signature,
619 return_type,
620 method->is_static(),
621 _value_state,
622 _value);
623 }