1 /*
2 * Copyright (c) 1997, 2021, 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 #if INCLUDE_JVMCI
34 #include "jvmci/jvmciJavaClasses.hpp"
35 #endif
36 #include "memory/universe.hpp"
37 #include "oops/method.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "prims/jniCheck.hpp"
40 #include "prims/jvmtiExport.hpp"
41 #include "runtime/handles.inline.hpp"
42 #include "runtime/interfaceSupport.inline.hpp"
43 #include "runtime/javaCalls.hpp"
44 #include "runtime/jniHandles.inline.hpp"
45 #include "runtime/mutexLocker.hpp"
46 #include "runtime/os.inline.hpp"
47 #include "runtime/sharedRuntime.hpp"
48 #include "runtime/signature.hpp"
49 #include "runtime/stubRoutines.hpp"
50 #include "runtime/thread.inline.hpp"
51
52 // -----------------------------------------------------
53 // Implementation of JavaCallWrapper
54
55 JavaCallWrapper::JavaCallWrapper(const methodHandle& callee_method, Handle receiver, JavaValue* result, TRAPS) {
56 JavaThread* thread = THREAD;
57
58 guarantee(thread->is_Java_thread(), "crucial check - the VM thread cannot and must not escape to Java code");
59 assert(!thread->owns_locks(), "must release all locks when leaving VM");
60 guarantee(thread->can_call_java(), "cannot make java calls from the native compiler");
61 _result = result;
62
63 // Allocate handle block for Java code. This must be done before we change thread_state to _thread_in_Java_or_stub,
64 // since it can potentially block.
65 JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(thread);
66
67 // clear any pending exception in thread (native calls start with no exception pending)
68 thread->clear_pending_exception();
69
70 // After this, we are official in JavaCode. This needs to be done before we change any of the thread local
71 // info, since we cannot find oops before the new information is set up completely.
72 ThreadStateTransition::transition_from_vm(thread, _thread_in_Java, true /* check_asyncs */);
73
74 // Make sure to set the oop's after the thread transition - since we can block there. No one is GC'ing
75 // the JavaCallWrapper before the entry frame is on the stack.
76 _callee_method = callee_method();
77 _receiver = receiver();
78
79 #ifdef CHECK_UNHANDLED_OOPS
80 THREAD->allow_unhandled_oop(&_receiver);
81 #endif // CHECK_UNHANDLED_OOPS
82
83 _thread = thread;
84 _handles = _thread->active_handles(); // save previous handle block & Java frame linkage
85
86 // For the profiler, the last_Java_frame information in thread must always be in
87 // legal state. We have no last Java frame if last_Java_sp == NULL so
88 // the valid transition is to clear _last_Java_sp and then reset the rest of
89 // the (platform specific) state.
90
91 _anchor.copy(_thread->frame_anchor());
92 _thread->frame_anchor()->clear();
93
94 debug_only(_thread->inc_java_call_counter());
95 _thread->set_active_handles(new_handles); // install new handle block and reset Java frame linkage
96
97 assert (_thread->thread_state() != _thread_in_native, "cannot set native pc to NULL");
98
99 MACOS_AARCH64_ONLY(_thread->enable_wx(WXExec));
100 }
101
102
103 JavaCallWrapper::~JavaCallWrapper() {
104 assert(_thread == JavaThread::current(), "must still be the same thread");
105
106 MACOS_AARCH64_ONLY(_thread->enable_wx(WXWrite));
107
108 // restore previous handle block & Java frame linkage
109 JNIHandleBlock *_old_handles = _thread->active_handles();
110 _thread->set_active_handles(_handles);
111
112 _thread->frame_anchor()->zap();
113
114 debug_only(_thread->dec_java_call_counter());
115
116 // Old thread-local info. has been restored. We are not back in the VM.
117 ThreadStateTransition::transition_from_java(_thread, _thread_in_vm);
118
119 // State has been restored now make the anchor frame visible for the profiler.
120 // Do this after the transition because this allows us to put an assert
121 // the Java->vm transition which checks to see that stack is not walkable
122 // on sparc/ia64 which will catch violations of the reseting of last_Java_frame
123 // invariants (i.e. _flags always cleared on return to Java)
124
125 _thread->frame_anchor()->copy(&_anchor);
126
127 // Release handles after we are marked as being inside the VM again, since this
128 // operation might block
129 JNIHandleBlock::release_block(_old_handles, _thread);
130
131 if (_thread->has_pending_exception() && _thread->has_last_Java_frame()) {
132 // If we get here, the Java code threw an exception that unwound a frame.
133 // It could be that the new frame anchor has not passed through the required
134 // StackWatermark barriers. Therefore, we process any such deferred unwind
135 // requests here.
136 StackWatermarkSet::after_unwind(_thread);
137 }
138 }
139
140
141 void JavaCallWrapper::oops_do(OopClosure* f) {
142 f->do_oop((oop*)&_receiver);
143 handles()->oops_do(f);
144 }
145
146
147 // Helper methods
148 static BasicType runtime_type_from(JavaValue* result) {
149 switch (result->get_type()) {
150 case T_BOOLEAN: // fall through
151 case T_CHAR : // fall through
152 case T_SHORT : // fall through
153 case T_INT : // fall through
154 #ifndef _LP64
155 case T_OBJECT : // fall through
156 case T_ARRAY : // fall through
157 #endif
158 case T_BYTE : // fall through
159 case T_VOID : return T_INT;
160 case T_LONG : return T_LONG;
161 case T_FLOAT : return T_FLOAT;
162 case T_DOUBLE : return T_DOUBLE;
163 #ifdef _LP64
164 case T_ARRAY : // fall through
165 case T_OBJECT: return T_OBJECT;
166 #endif
167 default:
168 ShouldNotReachHere();
169 return T_ILLEGAL;
170 }
171 }
172
173 // ============ Virtual calls ============
174
175 void JavaCalls::call_virtual(JavaValue* result, Klass* spec_klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
176 CallInfo callinfo;
177 Handle receiver = args->receiver();
178 Klass* recvrKlass = receiver.is_null() ? (Klass*)NULL : receiver->klass();
179 LinkInfo link_info(spec_klass, name, signature);
180 LinkResolver::resolve_virtual_call(
181 callinfo, receiver, recvrKlass, link_info, true, CHECK);
182 methodHandle method(THREAD, callinfo.selected_method());
183 assert(method.not_null(), "should have thrown exception");
184
185 // Invoke the method
186 JavaCalls::call(result, method, args, CHECK);
187 }
188
189
190 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, Klass* spec_klass, Symbol* name, Symbol* signature, TRAPS) {
191 JavaCallArguments args(receiver);
192 call_virtual(result, spec_klass, name, signature, &args, CHECK);
193 }
194
195
196 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, Klass* spec_klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
197 JavaCallArguments args(receiver);
198 args.push_oop(arg1);
199 call_virtual(result, spec_klass, name, signature, &args, CHECK);
200 }
201
202
203
204 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, Klass* spec_klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
205 JavaCallArguments args(receiver);
206 args.push_oop(arg1);
207 args.push_oop(arg2);
208 call_virtual(result, spec_klass, name, signature, &args, CHECK);
209 }
210
211
212 // ============ Special calls ============
213
214 void JavaCalls::call_special(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
215 CallInfo callinfo;
216 LinkInfo link_info(klass, name, signature);
217 LinkResolver::resolve_special_call(callinfo, args->receiver(), link_info, CHECK);
218 methodHandle method(THREAD, callinfo.selected_method());
219 assert(method.not_null(), "should have thrown exception");
220
221 // Invoke the method
222 JavaCalls::call(result, method, args, CHECK);
223 }
224
225
226 void JavaCalls::call_special(JavaValue* result, Handle receiver, Klass* klass, Symbol* name, Symbol* signature, TRAPS) {
227 JavaCallArguments args(receiver);
228 call_special(result, klass, name, signature, &args, CHECK);
229 }
230
231
232 void JavaCalls::call_special(JavaValue* result, Handle receiver, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
233 JavaCallArguments args(receiver);
234 args.push_oop(arg1);
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, Handle arg2, TRAPS) {
240 JavaCallArguments args(receiver);
241 args.push_oop(arg1);
242 args.push_oop(arg2);
243 call_special(result, klass, name, signature, &args, CHECK);
244 }
245
246
247 // ============ Static calls ============
248
249 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
250 CallInfo callinfo;
251 LinkInfo link_info(klass, name, signature);
252 LinkResolver::resolve_static_call(callinfo, link_info, true, CHECK);
253 methodHandle method(THREAD, callinfo.selected_method());
254 assert(method.not_null(), "should have thrown exception");
255
256 // Invoke the method
257 JavaCalls::call(result, method, args, CHECK);
258 }
259
260
261 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, TRAPS) {
262 JavaCallArguments args;
263 call_static(result, klass, name, signature, &args, CHECK);
264 }
265
266
267 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
268 JavaCallArguments args(arg1);
269 call_static(result, klass, name, signature, &args, CHECK);
270 }
271
272
273 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
274 JavaCallArguments args;
275 args.push_oop(arg1);
276 args.push_oop(arg2);
277 call_static(result, klass, name, signature, &args, CHECK);
278 }
279
280
281 void JavaCalls::call_static(JavaValue* result, Klass* klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, Handle arg3, TRAPS) {
282 JavaCallArguments args;
283 args.push_oop(arg1);
284 args.push_oop(arg2);
285 args.push_oop(arg3);
286 call_static(result, klass, name, signature, &args, CHECK);
287 }
288
289 // ============ allocate and initialize new object instance ============
290
291 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, JavaCallArguments* args, TRAPS) {
292 klass->initialize(CHECK_NH); // Quick no-op if already initialized.
293 Handle obj = klass->allocate_instance_handle(CHECK_NH);
294 JavaValue void_result(T_VOID);
295 args->set_receiver(obj); // inserts <obj> as the first argument.
296 JavaCalls::call_special(&void_result, klass,
297 vmSymbols::object_initializer_name(),
298 constructor_signature, args, CHECK_NH);
299 // Already returned a Null Handle if any exception is pending.
300 return obj;
301 }
302
303 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, TRAPS) {
304 JavaCallArguments args;
305 return JavaCalls::construct_new_instance(klass, constructor_signature, &args, THREAD);
306 }
307
308 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, Handle arg1, TRAPS) {
309 JavaCallArguments args;
310 args.push_oop(arg1);
311 return JavaCalls::construct_new_instance(klass, constructor_signature, &args, THREAD);
312 }
313
314 Handle JavaCalls::construct_new_instance(InstanceKlass* klass, Symbol* constructor_signature, Handle arg1, Handle arg2, TRAPS) {
315 JavaCallArguments args;
316 args.push_oop(arg1);
317 args.push_oop(arg2);
318 return JavaCalls::construct_new_instance(klass, constructor_signature, &args, THREAD);
319 }
320
321 // -------------------------------------------------
322 // Implementation of JavaCalls (low level)
323
324
325 void JavaCalls::call(JavaValue* result, const methodHandle& method, JavaCallArguments* args, TRAPS) {
326 // Check if we need to wrap a potential OS exception handler around thread.
327 // This is used for e.g. Win32 structured exception handlers.
328 // Need to wrap each and every time, since there might be native code down the
329 // stack that has installed its own exception handlers.
330 os::os_exception_wrapper(call_helper, result, method, args, THREAD);
331 }
332
333 void JavaCalls::call_helper(JavaValue* result, const methodHandle& method, JavaCallArguments* args, TRAPS) {
334
335 JavaThread* thread = THREAD;
336 assert(method.not_null(), "must have a method to call");
337 assert(!SafepointSynchronize::is_at_safepoint(), "call to Java code during VM operation");
338 assert(!thread->handle_area()->no_handle_mark_active(), "cannot call out to Java here");
339
340 // Verify the arguments
341 if (JVMCI_ONLY(args->alternative_target().is_null() &&) (DEBUG_ONLY(true ||) CheckJNICalls)) {
342 args->verify(method, result->get_type());
343 }
344 // Ignore call if method is empty
345 if (JVMCI_ONLY(args->alternative_target().is_null() &&) method->is_empty_method()) {
346 assert(result->get_type() == T_VOID, "an empty method must return a void value");
347 return;
348 }
349
350 #ifdef ASSERT
351 { InstanceKlass* holder = method->method_holder();
352 // A klass might not be initialized since JavaCall's might be used during the executing of
353 // the <clinit>. For example, a Thread.start might start executing on an object that is
354 // not fully initialized! (bad Java programming style)
355 assert(holder->is_linked(), "rewriting must have taken place");
356 }
357 #endif
358
359 CompilationPolicy::compile_if_required(method, CHECK);
360
361 // Since the call stub sets up like the interpreter we call the from_interpreted_entry
362 // so we can go compiled via a i2c. Otherwise initial entry method will always
363 // run interpreted.
364 address entry_point = method->from_interpreted_entry();
365 if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
366 entry_point = method->interpreter_entry();
367 }
368
369 // Figure out if the result value is an oop or not (Note: This is a different value
370 // than result_type. result_type will be T_INT of oops. (it is about size)
371 BasicType result_type = runtime_type_from(result);
372 bool oop_result_flag = is_reference_type(result->get_type());
373
374 // Find receiver
375 Handle receiver = (!method->is_static()) ? args->receiver() : Handle();
376
377 // When we reenter Java, we need to reenable the reserved/yellow zone which
378 // might already be disabled when we are in VM.
379 thread->stack_overflow_state()->reguard_stack_if_needed();
380
381 // Check that there are shadow pages available before changing thread state
382 // to Java. Calculate current_stack_pointer here to make sure
383 // stack_shadow_pages_available() and bang_stack_shadow_pages() use the same sp.
384 address sp = os::current_stack_pointer();
385 if (!os::stack_shadow_pages_available(THREAD, method, sp)) {
386 // Throw stack overflow exception with preinitialized exception.
387 Exceptions::throw_stack_overflow_exception(THREAD, __FILE__, __LINE__, method);
388 return;
389 } else {
390 // Touch pages checked if the OS needs them to be touched to be mapped.
391 os::map_stack_shadow_pages(sp);
392 }
393
394 // do call
395 { JavaCallWrapper link(method, receiver, result, CHECK);
396 { HandleMark hm(thread); // HandleMark used by HandleMarkCleaner
397
398 // NOTE: if we move the computation of the result_val_address inside
399 // the call to call_stub, the optimizer produces wrong code.
400 intptr_t* result_val_address = (intptr_t*)(result->get_value_addr());
401 intptr_t* parameter_address = args->parameters();
402 #if INCLUDE_JVMCI
403 // Gets the alternative target (if any) that should be called
404 Handle alternative_target = args->alternative_target();
405 if (!alternative_target.is_null()) {
406 // Must extract verified entry point from HotSpotNmethod after VM to Java
407 // transition in JavaCallWrapper constructor so that it is safe with
408 // respect to nmethod sweeping.
409 address verified_entry_point = (address) HotSpotJVMCI::InstalledCode::entryPoint(NULL, alternative_target());
410 if (verified_entry_point != NULL) {
411 thread->set_jvmci_alternate_call_target(verified_entry_point);
412 entry_point = method->adapter()->get_i2c_entry();
413 }
414 }
415 #endif
416 StubRoutines::call_stub()(
417 (address)&link,
418 // (intptr_t*)&(result->_value), // see NOTE above (compiler problem)
419 result_val_address, // see NOTE above (compiler problem)
420 result_type,
421 method(),
422 entry_point,
423 parameter_address,
424 args->size_of_parameters(),
425 CHECK
426 );
427
428 result = link.result(); // circumvent MS C++ 5.0 compiler bug (result is clobbered across call)
429 // Preserve oop return value across possible gc points
430 if (oop_result_flag) {
431 thread->set_vm_result(result->get_oop());
432 }
433 }
434 } // Exit JavaCallWrapper (can block - potential return oop must be preserved)
435
436 // Check if a thread stop or suspend should be executed
437 // The following assert was not realistic. Thread.stop can set that bit at any moment.
438 //assert(!thread->has_special_runtime_exit_condition(), "no async. exceptions should be installed");
439
440 // Restore possible oop return
441 if (oop_result_flag) {
442 result->set_oop(thread->vm_result());
443 thread->set_vm_result(NULL);
444 }
445 }
446
447
448 //--------------------------------------------------------------------------------------
449 // Implementation of JavaCallArguments
450
451 inline bool is_value_state_indirect_oop(uint state) {
452 assert(state != JavaCallArguments::value_state_oop,
453 "Checking for handles after removal");
454 assert(state < JavaCallArguments::value_state_limit,
455 "Invalid value state %u", state);
456 return state != JavaCallArguments::value_state_primitive;
457 }
458
459 inline oop resolve_indirect_oop(intptr_t value, uint state) {
460 switch (state) {
461 case JavaCallArguments::value_state_handle:
462 {
463 oop* ptr = reinterpret_cast<oop*>(value);
464 return Handle::raw_resolve(ptr);
465 }
466
467 case JavaCallArguments::value_state_jobject:
468 {
469 jobject obj = reinterpret_cast<jobject>(value);
470 return JNIHandles::resolve(obj);
471 }
472
473 default:
474 ShouldNotReachHere();
475 return NULL;
476 }
477 }
478
479 intptr_t* JavaCallArguments::parameters() {
480 // First convert all handles to oops
481 for(int i = 0; i < _size; i++) {
482 uint state = _value_state[i];
483 assert(state != value_state_oop, "Multiple handle conversions");
484 if (is_value_state_indirect_oop(state)) {
485 oop obj = resolve_indirect_oop(_value[i], state);
486 _value[i] = cast_from_oop<intptr_t>(obj);
487 _value_state[i] = value_state_oop;
488 }
489 }
490 // Return argument vector
491 return _value;
492 }
493
494
495 class SignatureChekker : public SignatureIterator {
496 private:
497 int _pos;
498 BasicType _return_type;
499 u_char* _value_state;
500 intptr_t* _value;
501
502 public:
503 SignatureChekker(Symbol* signature,
504 BasicType return_type,
505 bool is_static,
506 u_char* value_state,
507 intptr_t* value) :
508 SignatureIterator(signature),
509 _pos(0),
510 _return_type(return_type),
511 _value_state(value_state),
512 _value(value)
513 {
514 if (!is_static) {
515 check_value(true); // Receiver must be an oop
516 }
517 do_parameters_on(this);
518 check_return_type(return_type);
519 }
520
521 private:
522 void check_value(bool is_reference) {
523 uint state = _value_state[_pos++];
524 if (is_reference) {
525 guarantee(is_value_state_indirect_oop(state),
526 "signature does not match pushed arguments: %u at %d",
527 state, _pos - 1);
528 } else {
529 guarantee(state == JavaCallArguments::value_state_primitive,
530 "signature does not match pushed arguments: %u at %d",
531 state, _pos - 1);
532 }
533 }
534
535 void check_return_type(BasicType t) {
536 guarantee(t == _return_type, "return type does not match");
537 }
538
539 void check_single_word() {
540 check_value(false);
541 }
542
543 void check_double_word() {
544 check_value(false);
545 check_value(false);
546 }
547
548 void check_reference() {
549 intptr_t v = _value[_pos];
550 if (v != 0) {
551 // v is a "handle" referring to an oop, cast to integral type.
552 // There shouldn't be any handles in very low memory.
553 guarantee((size_t)v >= (size_t)os::vm_page_size(),
554 "Bad JNI oop argument %d: " PTR_FORMAT, _pos, v);
555 // Verify the pointee.
556 oop vv = resolve_indirect_oop(v, _value_state[_pos]);
557 guarantee(oopDesc::is_oop_or_null(vv, true),
558 "Bad JNI oop argument %d: " PTR_FORMAT " -> " PTR_FORMAT,
559 _pos, v, p2i(vv));
560 }
561
562 check_value(true); // Verify value state.
563 }
564
565 friend class SignatureIterator; // so do_parameters_on can call do_type
566 void do_type(BasicType type) {
567 switch (type) {
568 case T_BYTE:
569 case T_BOOLEAN:
570 case T_CHAR:
571 case T_SHORT:
572 case T_INT:
573 case T_FLOAT: // this one also
574 check_single_word(); break;
575 case T_LONG:
576 case T_DOUBLE:
577 check_double_word(); break;
578 case T_ARRAY:
579 case T_OBJECT:
580 check_reference(); break;
581 default:
582 ShouldNotReachHere();
583 }
584 }
585 };
586
587
588 void JavaCallArguments::verify(const methodHandle& method, BasicType return_type) {
589 guarantee(method->size_of_parameters() == size_of_parameters(), "wrong no. of arguments pushed");
590
591 // Treat T_OBJECT and T_ARRAY as the same
592 if (is_reference_type(return_type)) return_type = T_OBJECT;
593
594 // Check that oop information is correct
595 Symbol* signature = method->signature();
596
597 SignatureChekker sc(signature,
598 return_type,
599 method->is_static(),
600 _value_state,
601 _value);
602 }