1 /*
2 * Copyright (c) 1997, 2010, 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 "incls/_precompiled.incl"
26 #include "incls/_javaCalls.cpp.incl"
27
28 // -----------------------------------------------------
29 // Implementation of JavaCallWrapper
30
31 JavaCallWrapper::JavaCallWrapper(methodHandle callee_method, Handle receiver, JavaValue* result, TRAPS) {
32 JavaThread* thread = (JavaThread *)THREAD;
33 bool clear_pending_exception = true;
34
35 guarantee(thread->is_Java_thread(), "crucial check - the VM thread cannot and must not escape to Java code");
36 assert(!thread->owns_locks(), "must release all locks when leaving VM");
37 guarantee(!thread->is_Compiler_thread(), "cannot make java calls from the compiler");
38 _result = result;
39
40 // Allocate handle block for Java code. This must be done before we change thread_state to _thread_in_Java_or_stub,
41 // since it can potentially block.
42 JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(thread);
43
44 // After this, we are official in JavaCode. This needs to be done before we change any of the thread local
45 // info, since we cannot find oops before the new information is set up completely.
46 ThreadStateTransition::transition(thread, _thread_in_vm, _thread_in_Java);
47
48 // Make sure that we handle asynchronous stops and suspends _before_ we clear all thread state
49 // in JavaCallWrapper::JavaCallWrapper(). This way, we can decide if we need to do any pd actions
50 // to prepare for stop/suspend (flush register windows on sparcs, cache sp, or other state).
51 if (thread->has_special_runtime_exit_condition()) {
52 thread->handle_special_runtime_exit_condition();
53 if (HAS_PENDING_EXCEPTION) {
54 clear_pending_exception = false;
55 }
56 }
57
58
59 // Make sure to set the oop's after the thread transition - since we can block there. No one is GC'ing
60 // the JavaCallWrapper before the entry frame is on the stack.
61 _callee_method = callee_method();
62 _receiver = receiver();
63
64 #ifdef CHECK_UNHANDLED_OOPS
65 THREAD->allow_unhandled_oop(&_callee_method);
66 THREAD->allow_unhandled_oop(&_receiver);
67 #endif // CHECK_UNHANDLED_OOPS
68
69 _thread = (JavaThread *)thread;
70 _handles = _thread->active_handles(); // save previous handle block & Java frame linkage
71
72 // For the profiler, the last_Java_frame information in thread must always be in
73 // legal state. We have no last Java frame if last_Java_sp == NULL so
74 // the valid transition is to clear _last_Java_sp and then reset the rest of
75 // the (platform specific) state.
76
77 _anchor.copy(_thread->frame_anchor());
78 _thread->frame_anchor()->clear();
79
80 debug_only(_thread->inc_java_call_counter());
81 _thread->set_active_handles(new_handles); // install new handle block and reset Java frame linkage
82
83 assert (_thread->thread_state() != _thread_in_native, "cannot set native pc to NULL");
84
85 // clear any pending exception in thread (native calls start with no exception pending)
86 if(clear_pending_exception) {
87 _thread->clear_pending_exception();
88 }
89
90 if (_anchor.last_Java_sp() == NULL) {
91 _thread->record_base_of_stack_pointer();
92 }
93 }
94
95
96 JavaCallWrapper::~JavaCallWrapper() {
97 assert(_thread == JavaThread::current(), "must still be the same thread");
98
99 // restore previous handle block & Java frame linkage
100 JNIHandleBlock *_old_handles = _thread->active_handles();
101 _thread->set_active_handles(_handles);
102
103 _thread->frame_anchor()->zap();
104
105 debug_only(_thread->dec_java_call_counter());
106
107 if (_anchor.last_Java_sp() == NULL) {
108 _thread->set_base_of_stack_pointer(NULL);
109 }
110
111
112 // Old thread-local info. has been restored. We are not back in the VM.
113 ThreadStateTransition::transition_from_java(_thread, _thread_in_vm);
114
115 // State has been restored now make the anchor frame visible for the profiler.
116 // Do this after the transition because this allows us to put an assert
117 // the Java->vm transition which checks to see that stack is not walkable
118 // on sparc/ia64 which will catch violations of the reseting of last_Java_frame
119 // invariants (i.e. _flags always cleared on return to Java)
120
121 _thread->frame_anchor()->copy(&_anchor);
122
123 // Release handles after we are marked as being inside the VM again, since this
124 // operation might block
125 JNIHandleBlock::release_block(_old_handles, _thread);
126 }
127
128
129 void JavaCallWrapper::oops_do(OopClosure* f) {
130 f->do_oop((oop*)&_callee_method);
131 f->do_oop((oop*)&_receiver);
132 handles()->oops_do(f);
133 }
134
135
136 // Helper methods
137 static BasicType runtime_type_from(JavaValue* result) {
138 switch (result->get_type()) {
139 case T_BOOLEAN: // fall through
140 case T_CHAR : // fall through
141 case T_SHORT : // fall through
142 case T_INT : // fall through
143 #ifndef _LP64
144 case T_OBJECT : // fall through
145 case T_ARRAY : // fall through
146 #endif
147 case T_BYTE : // fall through
148 case T_VOID : return T_INT;
149 case T_LONG : return T_LONG;
150 case T_FLOAT : return T_FLOAT;
151 case T_DOUBLE : return T_DOUBLE;
152 #ifdef _LP64
153 case T_ARRAY : // fall through
154 case T_OBJECT: return T_OBJECT;
155 #endif
156 }
157 ShouldNotReachHere();
158 return T_ILLEGAL;
159 }
160
161 // ===== object constructor calls =====
162
163 void JavaCalls::call_default_constructor(JavaThread* thread, methodHandle method, Handle receiver, TRAPS) {
164 assert(method->name() == vmSymbols::object_initializer_name(), "Should only be called for default constructor");
165 assert(method->signature() == vmSymbols::void_method_signature(), "Should only be called for default constructor");
166
167 instanceKlass* ik = instanceKlass::cast(method->method_holder());
168 if (ik->is_initialized() && ik->has_vanilla_constructor()) {
169 // safe to skip constructor call
170 } else {
171 static JavaValue result(T_VOID);
172 JavaCallArguments args(receiver);
173 call(&result, method, &args, CHECK);
174 }
175 }
176
177 // ============ Virtual calls ============
178
179 void JavaCalls::call_virtual(JavaValue* result, KlassHandle spec_klass, symbolHandle name, symbolHandle signature, JavaCallArguments* args, TRAPS) {
180 CallInfo callinfo;
181 Handle receiver = args->receiver();
182 KlassHandle recvrKlass(THREAD, receiver.is_null() ? (klassOop)NULL : receiver->klass());
183 LinkResolver::resolve_virtual_call(
184 callinfo, receiver, recvrKlass, spec_klass, name, signature,
185 KlassHandle(), false, true, CHECK);
186 methodHandle method = callinfo.selected_method();
187 assert(method.not_null(), "should have thrown exception");
188
189 // Invoke the method
190 JavaCalls::call(result, method, args, CHECK);
191 }
192
193
194 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, symbolHandle name, symbolHandle signature, TRAPS) {
195 JavaCallArguments args(receiver); // One oop argument
196 call_virtual(result, spec_klass, name, signature, &args, CHECK);
197 }
198
199
200 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, symbolHandle name, symbolHandle signature, Handle arg1, TRAPS) {
201 JavaCallArguments args(receiver); // One oop argument
202 args.push_oop(arg1);
203 call_virtual(result, spec_klass, name, signature, &args, CHECK);
204 }
205
206
207
208 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, symbolHandle name, symbolHandle signature, Handle arg1, Handle arg2, TRAPS) {
209 JavaCallArguments args(receiver); // One oop argument
210 args.push_oop(arg1);
211 args.push_oop(arg2);
212 call_virtual(result, spec_klass, name, signature, &args, CHECK);
213 }
214
215
216 // ============ Special calls ============
217
218 void JavaCalls::call_special(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, JavaCallArguments* args, TRAPS) {
219 CallInfo callinfo;
220 LinkResolver::resolve_special_call(callinfo, klass, name, signature, KlassHandle(), false, CHECK);
221 methodHandle method = callinfo.selected_method();
222 assert(method.not_null(), "should have thrown exception");
223
224 // Invoke the method
225 JavaCalls::call(result, method, args, CHECK);
226 }
227
228
229 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, symbolHandle name, symbolHandle signature, TRAPS) {
230 JavaCallArguments args(receiver); // One oop argument
231 call_special(result, klass, name, signature, &args, CHECK);
232 }
233
234
235 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, symbolHandle name, symbolHandle signature, Handle arg1, TRAPS) {
236 JavaCallArguments args(receiver); // One oop argument
237 args.push_oop(arg1);
238 call_special(result, klass, name, signature, &args, CHECK);
239 }
240
241
242 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, symbolHandle name, symbolHandle signature, Handle arg1, Handle arg2, TRAPS) {
243 JavaCallArguments args(receiver); // One oop argument
244 args.push_oop(arg1);
245 args.push_oop(arg2);
246 call_special(result, klass, name, signature, &args, CHECK);
247 }
248
249
250 // ============ Static calls ============
251
252 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, JavaCallArguments* args, TRAPS) {
253 CallInfo callinfo;
254 LinkResolver::resolve_static_call(callinfo, klass, name, signature, KlassHandle(), false, true, CHECK);
255 methodHandle method = callinfo.selected_method();
256 assert(method.not_null(), "should have thrown exception");
257
258 // Invoke the method
259 JavaCalls::call(result, method, args, CHECK);
260 }
261
262
263 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, TRAPS) {
264 JavaCallArguments args; // No argument
265 call_static(result, klass, name, signature, &args, CHECK);
266 }
267
268
269 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, Handle arg1, TRAPS) {
270 JavaCallArguments args(arg1); // One oop argument
271 call_static(result, klass, name, signature, &args, CHECK);
272 }
273
274
275 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, Handle arg1, Handle arg2, TRAPS) {
276 JavaCallArguments args; // One oop argument
277 args.push_oop(arg1);
278 args.push_oop(arg2);
279 call_static(result, klass, name, signature, &args, CHECK);
280 }
281
282
283 // -------------------------------------------------
284 // Implementation of JavaCalls (low level)
285
286
287 void JavaCalls::call(JavaValue* result, methodHandle method, JavaCallArguments* args, TRAPS) {
288 // Check if we need to wrap a potential OS exception handler around thread
289 // This is used for e.g. Win32 structured exception handlers
290 assert(THREAD->is_Java_thread(), "only JavaThreads can make JavaCalls");
291 // Need to wrap each and everytime, since there might be native code down the
292 // stack that has installed its own exception handlers
293 os::os_exception_wrapper(call_helper, result, &method, args, THREAD);
294 }
295
296 void JavaCalls::call_helper(JavaValue* result, methodHandle* m, JavaCallArguments* args, TRAPS) {
297 methodHandle method = *m;
298 JavaThread* thread = (JavaThread*)THREAD;
299 assert(thread->is_Java_thread(), "must be called by a java thread");
300 assert(method.not_null(), "must have a method to call");
301 assert(!SafepointSynchronize::is_at_safepoint(), "call to Java code during VM operation");
302 assert(!thread->handle_area()->no_handle_mark_active(), "cannot call out to Java here");
303
304
305 CHECK_UNHANDLED_OOPS_ONLY(thread->clear_unhandled_oops();)
306
307 // Verify the arguments
308
309 if (CheckJNICalls) {
310 args->verify(method, result->get_type(), thread);
311 }
312 else debug_only(args->verify(method, result->get_type(), thread));
313
314 // Ignore call if method is empty
315 if (method->is_empty_method()) {
316 assert(result->get_type() == T_VOID, "an empty method must return a void value");
317 return;
318 }
319
320
321 #ifdef ASSERT
322 { klassOop holder = method->method_holder();
323 // A klass might not be initialized since JavaCall's might be used during the executing of
324 // the <clinit>. For example, a Thread.start might start executing on an object that is
325 // not fully initialized! (bad Java programming style)
326 assert(instanceKlass::cast(holder)->is_linked(), "rewritting must have taken place");
327 }
328 #endif
329
330
331 assert(!thread->is_Compiler_thread(), "cannot compile from the compiler");
332 if (CompilationPolicy::must_be_compiled(method)) {
333 CompileBroker::compile_method(method, InvocationEntryBci,
334 CompLevel_initial_compile,
335 methodHandle(), 0, "must_be_compiled", CHECK);
336 }
337
338 // Since the call stub sets up like the interpreter we call the from_interpreted_entry
339 // so we can go compiled via a i2c. Otherwise initial entry method will always
340 // run interpreted.
341 address entry_point = method->from_interpreted_entry();
342 if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
343 entry_point = method->interpreter_entry();
344 }
345
346 // Figure out if the result value is an oop or not (Note: This is a different value
347 // than result_type. result_type will be T_INT of oops. (it is about size)
348 BasicType result_type = runtime_type_from(result);
349 bool oop_result_flag = (result->get_type() == T_OBJECT || result->get_type() == T_ARRAY);
350
351 // NOTE: if we move the computation of the result_val_address inside
352 // the call to call_stub, the optimizer produces wrong code.
353 intptr_t* result_val_address = (intptr_t*)(result->get_value_addr());
354
355 // Find receiver
356 Handle receiver = (!method->is_static()) ? args->receiver() : Handle();
357
358 // When we reenter Java, we need to reenable the yellow zone which
359 // might already be disabled when we are in VM.
360 if (thread->stack_yellow_zone_disabled()) {
361 thread->reguard_stack();
362 }
363
364 // Check that there are shadow pages available before changing thread state
365 // to Java
366 if (!os::stack_shadow_pages_available(THREAD, method)) {
367 // Throw stack overflow exception with preinitialized exception.
368 Exceptions::throw_stack_overflow_exception(THREAD, __FILE__, __LINE__);
369 return;
370 } else {
371 // Touch pages checked if the OS needs them to be touched to be mapped.
372 os::bang_stack_shadow_pages();
373 }
374
375 // do call
376 { JavaCallWrapper link(method, receiver, result, CHECK);
377 { HandleMark hm(thread); // HandleMark used by HandleMarkCleaner
378
379 StubRoutines::call_stub()(
380 (address)&link,
381 // (intptr_t*)&(result->_value), // see NOTE above (compiler problem)
382 result_val_address, // see NOTE above (compiler problem)
383 result_type,
384 method(),
385 entry_point,
386 args->parameters(),
387 args->size_of_parameters(),
388 CHECK
389 );
390
391 result = link.result(); // circumvent MS C++ 5.0 compiler bug (result is clobbered across call)
392 // Preserve oop return value across possible gc points
393 if (oop_result_flag) {
394 thread->set_vm_result((oop) result->get_jobject());
395 }
396 }
397 } // Exit JavaCallWrapper (can block - potential return oop must be preserved)
398
399 // Check if a thread stop or suspend should be executed
400 // The following assert was not realistic. Thread.stop can set that bit at any moment.
401 //assert(!thread->has_special_runtime_exit_condition(), "no async. exceptions should be installed");
402
403 // Restore possible oop return
404 if (oop_result_flag) {
405 result->set_jobject((jobject)thread->vm_result());
406 thread->set_vm_result(NULL);
407 }
408 }
409
410
411 //--------------------------------------------------------------------------------------
412 // Implementation of JavaCallArguments
413
414 intptr_t* JavaCallArguments::parameters() {
415 // First convert all handles to oops
416 for(int i = 0; i < _size; i++) {
417 if (_is_oop[i]) {
418 // Handle conversion
419 _value[i] = (intptr_t)Handle::raw_resolve((oop *)_value[i]);
420 }
421 }
422 // Return argument vector
423 return _value;
424 }
425
426
427 class SignatureChekker : public SignatureIterator {
428 private:
429 bool *_is_oop;
430 int _pos;
431 BasicType _return_type;
432 intptr_t* _value;
433 Thread* _thread;
434
435 public:
436 bool _is_return;
437
438 SignatureChekker(symbolHandle signature, BasicType return_type, bool is_static, bool* is_oop, intptr_t* value, Thread* thread) : SignatureIterator(signature) {
439 _is_oop = is_oop;
440 _is_return = false;
441 _return_type = return_type;
442 _pos = 0;
443 _value = value;
444 _thread = thread;
445
446 if (!is_static) {
447 check_value(true); // Receiver must be an oop
448 }
449 }
450
451 void check_value(bool type) {
452 guarantee(_is_oop[_pos++] == type, "signature does not match pushed arguments");
453 }
454
455 void check_doing_return(bool state) { _is_return = state; }
456
457 void check_return_type(BasicType t) {
458 guarantee(_is_return && t == _return_type, "return type does not match");
459 }
460
461 void check_int(BasicType t) {
462 if (_is_return) {
463 check_return_type(t);
464 return;
465 }
466 check_value(false);
467 }
468
469 void check_double(BasicType t) { check_long(t); }
470
471 void check_long(BasicType t) {
472 if (_is_return) {
473 check_return_type(t);
474 return;
475 }
476
477 check_value(false);
478 check_value(false);
479 }
480
481 void check_obj(BasicType t) {
482 if (_is_return) {
483 check_return_type(t);
484 return;
485 }
486
487 // verify handle and the oop pointed to by handle
488 int p = _pos;
489 bool bad = false;
490 // If argument is oop
491 if (_is_oop[p]) {
492 intptr_t v = _value[p];
493 if (v != 0 ) {
494 size_t t = (size_t)v;
495 bad = (t < (size_t)os::vm_page_size() ) || !Handle::raw_resolve((oop *)v)->is_oop_or_null(true);
496 if (CheckJNICalls && bad) {
497 ReportJNIFatalError((JavaThread*)_thread, "Bad JNI oop argument");
498 }
499 }
500 // for the regular debug case.
501 assert(!bad, "Bad JNI oop argument");
502 }
503
504 check_value(true);
505 }
506
507 void do_bool() { check_int(T_BOOLEAN); }
508 void do_char() { check_int(T_CHAR); }
509 void do_float() { check_int(T_FLOAT); }
510 void do_double() { check_double(T_DOUBLE); }
511 void do_byte() { check_int(T_BYTE); }
512 void do_short() { check_int(T_SHORT); }
513 void do_int() { check_int(T_INT); }
514 void do_long() { check_long(T_LONG); }
515 void do_void() { check_return_type(T_VOID); }
516 void do_object(int begin, int end) { check_obj(T_OBJECT); }
517 void do_array(int begin, int end) { check_obj(T_OBJECT); }
518 };
519
520
521 void JavaCallArguments::verify(methodHandle method, BasicType return_type,
522 Thread *thread) {
523 guarantee(method->size_of_parameters() == size_of_parameters(), "wrong no. of arguments pushed");
524
525 // Treat T_OBJECT and T_ARRAY as the same
526 if (return_type == T_ARRAY) return_type = T_OBJECT;
527
528 // Check that oop information is correct
529 symbolHandle signature (thread, method->signature());
530
531 SignatureChekker sc(signature, return_type, method->is_static(),_is_oop, _value, thread);
532 sc.iterate_parameters();
533 sc.check_doing_return(true);
534 sc.iterate_returntype();
535 }
536