1 /*
2 * Copyright (c) 1997, 2022, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.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 "prims/jvmtiExport.hpp"
38 #include "runtime/handles.inline.hpp"
39 #include "runtime/interfaceSupport.inline.hpp"
40 #include "runtime/javaCalls.hpp"
41 #include "runtime/javaThread.hpp"
42 #include "runtime/jniHandles.inline.hpp"
43 #include "runtime/mutexLocker.hpp"
44 #include "runtime/os.inline.hpp"
45 #include "runtime/sharedRuntime.hpp"
46 #include "runtime/signature.hpp"
47 #include "runtime/stubRoutines.hpp"
48 #include "runtime/thread.inline.hpp"
49 #if INCLUDE_JVMCI
50 #include "jvmci/jvmciJavaClasses.hpp"
51 #endif
52
53 // -----------------------------------------------------
54 // Implementation of JavaCallWrapper
55
56 JavaCallWrapper::JavaCallWrapper(const methodHandle& callee_method, Handle receiver, JavaValue* result, TRAPS) {
57 JavaThread* thread = THREAD;
58
59 guarantee(thread->is_Java_thread(), "crucial check - the VM thread cannot and must not escape to Java code");
60 assert(!thread->owns_locks(), "must release all locks when leaving VM");
61 guarantee(thread->can_call_java(), "cannot make java calls from the native compiler");
62 _result = result;
63
64 // Allocate handle block for Java code. This must be done before we change thread_state to _thread_in_Java_or_stub,
65 // since it can potentially block.
66 JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(thread);
67
68 // clear any pending exception in thread (native calls start with no exception pending)
69 thread->clear_pending_exception();
70
71 // After this, we are official in JavaCode. This needs to be done before we change any of the thread local
72 // info, since we cannot find oops before the new information is set up completely.
73 ThreadStateTransition::transition_from_vm(thread, _thread_in_Java, true /* check_asyncs */);
74
75 // Make sure to set the oop's after the thread transition - since we can block there. No one is GC'ing
76 // the JavaCallWrapper before the entry frame is on the stack.
77 _callee_method = callee_method();
78 _receiver = receiver();
79
80 #ifdef CHECK_UNHANDLED_OOPS
81 THREAD->allow_unhandled_oop(&_receiver);
82 #endif // CHECK_UNHANDLED_OOPS
83
84 _thread = thread;
85 _handles = _thread->active_handles(); // save previous handle block & Java frame linkage
86
87 // For the profiler, the last_Java_frame information in thread must always be in
88 // legal state. We have no last Java frame if last_Java_sp == NULL so
89 // the valid transition is to clear _last_Java_sp and then reset the rest of
90 // the (platform specific) state.
91
92 _anchor.copy(_thread->frame_anchor());
93 _thread->frame_anchor()->clear();
94
95 debug_only(_thread->inc_java_call_counter());
96 _thread->set_active_handles(new_handles); // install new handle block and reset Java frame linkage
97
98 assert (_thread->thread_state() != _thread_in_native, "cannot set native pc to NULL");
99
100 MACOS_AARCH64_ONLY(_thread->enable_wx(WXExec));
101 }
102
103
104 JavaCallWrapper::~JavaCallWrapper() {
105 assert(_thread == JavaThread::current(), "must still be the same thread");
106
107 MACOS_AARCH64_ONLY(_thread->enable_wx(WXWrite));
108
109 // restore previous handle block & Java frame linkage
110 JNIHandleBlock *_old_handles = _thread->active_handles();
111 _thread->set_active_handles(_handles);
112
113 _thread->frame_anchor()->zap();
114
115 debug_only(_thread->dec_java_call_counter());
116
117 // Old thread-local info. has been restored. We are not back in the VM.
118 ThreadStateTransition::transition_from_java(_thread, _thread_in_vm);
119
120 // State has been restored now make the anchor frame visible for the profiler.
121 // Do this after the transition because this allows us to put an assert
122 // the Java->vm transition which checks to see that stack is not walkable
123 // on sparc/ia64 which will catch violations of the resetting of last_Java_frame
124 // invariants (i.e. _flags always cleared on return to Java)
125
126 _thread->frame_anchor()->copy(&_anchor);
127
128 // Release handles after we are marked as being inside the VM again, since this
129 // operation might block
130 JNIHandleBlock::release_block(_old_handles, _thread);
131
132 if (_thread->has_pending_exception() && _thread->has_last_Java_frame()) {
133 // If we get here, the Java code threw an exception that unwound a frame.
134 // It could be that the new frame anchor has not passed through the required
135 // StackWatermark barriers. Therefore, we process any such deferred unwind
136 // requests here.
137 StackWatermarkSet::after_unwind(_thread);
138 }
139 }
140
141
142 void JavaCallWrapper::oops_do(OopClosure* f) {
143 f->do_oop((oop*)&_receiver);
144 handles()->oops_do(f);
145 }
146
147
148 // Helper methods
149 static BasicType runtime_type_from(JavaValue* result) {
150 switch (result->get_type()) {
151 case T_BOOLEAN: // fall through
152 case T_CHAR : // fall through
153 case T_SHORT : // fall through
154 case T_INT : // fall through
155 #ifndef _LP64
156 case T_OBJECT : // fall through
157 case T_ARRAY : // fall through
158 #endif
159 case T_BYTE : // fall through
160 case T_VOID : return T_INT;
161 case T_LONG : return T_LONG;
162 case T_FLOAT : return T_FLOAT;
163 case T_DOUBLE : return T_DOUBLE;
164 #ifdef _LP64
165 case T_ARRAY : // fall through
166 case T_OBJECT: return T_OBJECT;
167 #endif
168 default:
169 ShouldNotReachHere();
170 return T_ILLEGAL;
171 }
172 }
173
174 // ============ Virtual calls ============
175
176 void JavaCalls::call_virtual(JavaValue* result, Klass* spec_klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
177 CallInfo callinfo;
178 Handle receiver = args->receiver();
179 Klass* recvrKlass = receiver.is_null() ? (Klass*)NULL : receiver->klass();
180 LinkInfo link_info(spec_klass, name, signature);
181 LinkResolver::resolve_virtual_call(
182 callinfo, receiver, recvrKlass, link_info, true, CHECK);
183 methodHandle method(THREAD, callinfo.selected_method());
184 assert(method.not_null(), "should have thrown exception");
185
186 // Invoke the method
187 JavaCalls::call(result, method, args, CHECK);
188 }
189
190
191 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, Klass* spec_klass, Symbol* name, Symbol* signature, TRAPS) {
192 JavaCallArguments args(receiver);
193 call_virtual(result, spec_klass, name, signature, &args, CHECK);
194 }
195
196
197 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, Klass* spec_klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
198 JavaCallArguments args(receiver);
199 args.push_oop(arg1);
200 call_virtual(result, spec_klass, name, signature, &args, CHECK);
201 }
202
203
204
205 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, Klass* spec_klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
206 JavaCallArguments args(receiver);
207 args.push_oop(arg1);
208 args.push_oop(arg2);
209 call_virtual(result, spec_klass, name, signature, &args, CHECK);
210 }
211
212
213 // ============ Special calls ============
214
215 void JavaCalls::call_special(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
216 CallInfo callinfo;
217 LinkInfo link_info(klass, name, signature);
218 LinkResolver::resolve_special_call(callinfo, args->receiver(), link_info, CHECK);
219 methodHandle method(THREAD, callinfo.selected_method());
220 assert(method.not_null(), "should have thrown exception");
221
222 // Invoke the method
223 JavaCalls::call(result, method, args, CHECK);
224 }
225
226
227 void JavaCalls::call_special(JavaValue* result, Handle receiver, Klass* klass, Symbol* name, Symbol* signature, TRAPS) {
228 JavaCallArguments args(receiver);
229 call_special(result, klass, name, signature, &args, CHECK);
230 }
231
232
233 void JavaCalls::call_special(JavaValue* result, Handle receiver, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
234 JavaCallArguments args(receiver);
235 args.push_oop(arg1);
236 call_special(result, klass, name, signature, &args, CHECK);
237 }
238
239
240 void JavaCalls::call_special(JavaValue* result, Handle receiver, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
241 JavaCallArguments args(receiver);
242 args.push_oop(arg1);
243 args.push_oop(arg2);
244 call_special(result, klass, name, signature, &args, CHECK);
245 }
246
247
248 // ============ Static calls ============
249
250 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
251 CallInfo callinfo;
252 LinkInfo link_info(klass, name, signature);
253 LinkResolver::resolve_static_call(callinfo, link_info, true, CHECK);
254 methodHandle method(THREAD, callinfo.selected_method());
255 assert(method.not_null(), "should have thrown exception");
256
257 // Invoke the method
258 JavaCalls::call(result, method, args, CHECK);
259 }
260
261
262 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, TRAPS) {
263 JavaCallArguments args;
264 call_static(result, klass, name, signature, &args, CHECK);
265 }
266
267
268 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
269 JavaCallArguments args(arg1);
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, Handle arg2, TRAPS) {
275 JavaCallArguments args;
276 args.push_oop(arg1);
277 args.push_oop(arg2);
278 call_static(result, klass, name, signature, &args, CHECK);
279 }
280
281
282 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, Handle arg3, TRAPS) {
283 JavaCallArguments args;
284 args.push_oop(arg1);
285 args.push_oop(arg2);
286 args.push_oop(arg3);
287 call_static(result, klass, name, signature, &args, CHECK);
288 }
289
290 // ============ allocate and initialize new object instance ============
291
292 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, JavaCallArguments* args, TRAPS) {
293 klass->initialize(CHECK_NH); // Quick no-op if already initialized.
294 Handle obj = klass->allocate_instance_handle(CHECK_NH);
295 JavaValue void_result(T_VOID);
296 args->set_receiver(obj); // inserts <obj> as the first argument.
297 JavaCalls::call_special(&void_result, klass,
298 vmSymbols::object_initializer_name(),
299 constructor_signature, args, CHECK_NH);
300 // Already returned a Null Handle if any exception is pending.
301 return obj;
302 }
303
304 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, TRAPS) {
305 JavaCallArguments args;
306 return JavaCalls::construct_new_instance(klass, constructor_signature, &args, THREAD);
307 }
308
309 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, Handle arg1, TRAPS) {
310 JavaCallArguments args;
311 args.push_oop(arg1);
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, Handle arg2, TRAPS) {
316 JavaCallArguments args;
317 args.push_oop(arg1);
318 args.push_oop(arg2);
319 return JavaCalls::construct_new_instance(klass, constructor_signature, &args, THREAD);
320 }
321
322 // -------------------------------------------------
323 // Implementation of JavaCalls (low level)
324
325
326 void JavaCalls::call(JavaValue* result, const methodHandle& method, JavaCallArguments* args, TRAPS) {
327 // Check if we need to wrap a potential OS exception handler around thread.
328 // This is used for e.g. Win32 structured exception handlers.
329 // Need to wrap each and every time, since there might be native code down the
330 // stack that has installed its own exception handlers.
331 os::os_exception_wrapper(call_helper, result, method, args, THREAD);
332 }
333
334 void JavaCalls::call_helper(JavaValue* result, const methodHandle& method, JavaCallArguments* args, TRAPS) {
335
336 JavaThread* thread = THREAD;
337 assert(method.not_null(), "must have a method to call");
338 assert(!SafepointSynchronize::is_at_safepoint(), "call to Java code during VM operation");
339 assert(!thread->handle_area()->no_handle_mark_active(), "cannot call out to Java here");
340
341 // Verify the arguments
342 if (JVMCI_ONLY(args->alternative_target().is_null() &&) (DEBUG_ONLY(true ||) CheckJNICalls)) {
343 args->verify(method, result->get_type());
344 }
345 // Ignore call if method is empty
346 if (JVMCI_ONLY(args->alternative_target().is_null() &&) method->is_empty_method()) {
347 assert(result->get_type() == T_VOID, "an empty method must return a void value");
348 return;
349 }
350
351 #ifdef ASSERT
352 { InstanceKlass* holder = method->method_holder();
353 // A klass might not be initialized since JavaCall's might be used during the executing of
354 // the <clinit>. For example, a Thread.start might start executing on an object that is
355 // not fully initialized! (bad Java programming style)
356 assert(holder->is_linked(), "rewriting must have taken place");
357 }
358 #endif
359
360 CompilationPolicy::compile_if_required(method, CHECK);
361
362 // Since the call stub sets up like the interpreter we call the from_interpreted_entry
363 // so we can go compiled via a i2c. Otherwise initial entry method will always
364 // run interpreted.
365 address entry_point = method->from_interpreted_entry();
366 if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
367 entry_point = method->interpreter_entry();
368 }
369
370 // Figure out if the result value is an oop or not (Note: This is a different value
371 // than result_type. result_type will be T_INT of oops. (it is about size)
372 BasicType result_type = runtime_type_from(result);
373 bool oop_result_flag = is_reference_type(result->get_type());
374
375 // Find receiver
376 Handle receiver = (!method->is_static()) ? args->receiver() : Handle();
377
378 // When we reenter Java, we need to re-enable the reserved/yellow zone which
379 // might already be disabled when we are in VM.
380 thread->stack_overflow_state()->reguard_stack_if_needed();
381
382 // Check that there are shadow pages available before changing thread state
383 // to Java. Calculate current_stack_pointer here to make sure
384 // stack_shadow_pages_available() and map_stack_shadow_pages() use the same sp.
385 address sp = os::current_stack_pointer();
386 if (!os::stack_shadow_pages_available(THREAD, method, sp)) {
387 // Throw stack overflow exception with preinitialized exception.
388 Exceptions::throw_stack_overflow_exception(THREAD, __FILE__, __LINE__, method);
389 return;
390 } else {
391 // Touch pages checked if the OS needs them to be touched to be mapped.
392 os::map_stack_shadow_pages(sp);
393 }
394
395 // do call
396 { JavaCallWrapper link(method, receiver, result, CHECK);
397 { HandleMark hm(thread); // HandleMark used by HandleMarkCleaner
398
399 // NOTE: if we move the computation of the result_val_address inside
400 // the call to call_stub, the optimizer produces wrong code.
401 intptr_t* result_val_address = (intptr_t*)(result->get_value_addr());
402 intptr_t* parameter_address = args->parameters();
403 #if INCLUDE_JVMCI
404 // Gets the alternative target (if any) that should be called
405 Handle alternative_target = args->alternative_target();
406 if (!alternative_target.is_null()) {
407 // Must extract verified entry point from HotSpotNmethod after VM to Java
408 // transition in JavaCallWrapper constructor so that it is safe with
409 // respect to nmethod sweeping.
410 address verified_entry_point = (address) HotSpotJVMCI::InstalledCode::entryPoint(NULL, alternative_target());
411 if (verified_entry_point != NULL) {
412 thread->set_jvmci_alternate_call_target(verified_entry_point);
413 entry_point = method->adapter()->get_i2c_entry();
414 }
415 }
416 #endif
417 StubRoutines::call_stub()(
418 (address)&link,
419 // (intptr_t*)&(result->_value), // see NOTE above (compiler problem)
420 result_val_address, // see NOTE above (compiler problem)
421 result_type,
422 method(),
423 entry_point,
424 parameter_address,
425 args->size_of_parameters(),
426 CHECK
427 );
428
429 result = link.result(); // circumvent MS C++ 5.0 compiler bug (result is clobbered across call)
430 // Preserve oop return value across possible gc points
431 if (oop_result_flag) {
432 thread->set_vm_result(result->get_oop());
433 }
434 }
435 } // Exit JavaCallWrapper (can block - potential return oop must be preserved)
436
437 // Check if a thread stop or suspend should be executed
438 // The following assert was not realistic. Thread.stop can set that bit at any moment.
439 //assert(!thread->has_special_runtime_exit_condition(), "no async. exceptions should be installed");
440
441 // Restore possible oop return
442 if (oop_result_flag) {
443 result->set_oop(thread->vm_result());
444 thread->set_vm_result(NULL);
445 }
446 }
447
448
449 //--------------------------------------------------------------------------------------
450 // Implementation of JavaCallArguments
451
452 inline bool is_value_state_indirect_oop(uint state) {
453 assert(state != JavaCallArguments::value_state_oop,
454 "Checking for handles after removal");
455 assert(state < JavaCallArguments::value_state_limit,
456 "Invalid value state %u", state);
457 return state != JavaCallArguments::value_state_primitive;
458 }
459
460 inline oop resolve_indirect_oop(intptr_t value, uint state) {
461 switch (state) {
462 case JavaCallArguments::value_state_handle:
463 {
464 oop* ptr = reinterpret_cast<oop*>(value);
465 return Handle::raw_resolve(ptr);
466 }
467
468 case JavaCallArguments::value_state_jobject:
469 {
470 jobject obj = reinterpret_cast<jobject>(value);
471 return JNIHandles::resolve(obj);
472 }
473
474 default:
475 ShouldNotReachHere();
476 return NULL;
477 }
478 }
479
480 intptr_t* JavaCallArguments::parameters() {
481 // First convert all handles to oops
482 for(int i = 0; i < _size; i++) {
483 uint state = _value_state[i];
484 assert(state != value_state_oop, "Multiple handle conversions");
485 if (is_value_state_indirect_oop(state)) {
486 oop obj = resolve_indirect_oop(_value[i], state);
487 _value[i] = cast_from_oop<intptr_t>(obj);
488 _value_state[i] = value_state_oop;
489 }
490 }
491 // Return argument vector
492 return _value;
493 }
494
495
496 class SignatureChekker : public SignatureIterator {
497 private:
498 int _pos;
499 BasicType _return_type;
500 u_char* _value_state;
501 intptr_t* _value;
502
503 public:
504 SignatureChekker(Symbol* signature,
505 BasicType return_type,
506 bool is_static,
507 u_char* value_state,
508 intptr_t* value) :
509 SignatureIterator(signature),
510 _pos(0),
511 _return_type(return_type),
512 _value_state(value_state),
513 _value(value)
514 {
515 if (!is_static) {
516 check_value(true); // Receiver must be an oop
517 }
518 do_parameters_on(this);
519 check_return_type(return_type);
520 }
521
522 private:
523 void check_value(bool is_reference) {
524 uint state = _value_state[_pos++];
525 if (is_reference) {
526 guarantee(is_value_state_indirect_oop(state),
527 "signature does not match pushed arguments: %u at %d",
528 state, _pos - 1);
529 } else {
530 guarantee(state == JavaCallArguments::value_state_primitive,
531 "signature does not match pushed arguments: %u at %d",
532 state, _pos - 1);
533 }
534 }
535
536 void check_return_type(BasicType t) {
537 guarantee(t == _return_type, "return type does not match");
538 }
539
540 void check_single_word() {
541 check_value(false);
542 }
543
544 void check_double_word() {
545 check_value(false);
546 check_value(false);
547 }
548
549 void check_reference() {
550 intptr_t v = _value[_pos];
551 if (v != 0) {
552 // v is a "handle" referring to an oop, cast to integral type.
553 // There shouldn't be any handles in very low memory.
554 guarantee((size_t)v >= (size_t)os::vm_page_size(),
555 "Bad JNI oop argument %d: " PTR_FORMAT, _pos, v);
556 // Verify the pointee.
557 oop vv = resolve_indirect_oop(v, _value_state[_pos]);
558 guarantee(oopDesc::is_oop_or_null(vv, true),
559 "Bad JNI oop argument %d: " PTR_FORMAT " -> " PTR_FORMAT,
560 _pos, v, p2i(vv));
561 }
562
563 check_value(true); // Verify value state.
564 }
565
566 friend class SignatureIterator; // so do_parameters_on can call do_type
567 void do_type(BasicType type) {
568 switch (type) {
569 case T_BYTE:
570 case T_BOOLEAN:
571 case T_CHAR:
572 case T_SHORT:
573 case T_INT:
574 case T_FLOAT: // this one also
575 check_single_word(); break;
576 case T_LONG:
577 case T_DOUBLE:
578 check_double_word(); break;
579 case T_ARRAY:
580 case T_OBJECT:
581 check_reference(); break;
582 default:
583 ShouldNotReachHere();
584 }
585 }
586 };
587
588
589 void JavaCallArguments::verify(const methodHandle& method, BasicType return_type) {
590 guarantee(method->size_of_parameters() == size_of_parameters(), "wrong no. of arguments pushed");
591
592 // Treat T_OBJECT and T_ARRAY as the same
593 if (is_reference_type(return_type)) return_type = T_OBJECT;
594
595 // Check that oop information is correct
596 Symbol* signature = method->signature();
597
598 SignatureChekker sc(signature,
599 return_type,
600 method->is_static(),
601 _value_state,
602 _value);
603 }