1 /*
2 * Copyright (c) 1998, 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 "precompiled.hpp"
26 #include "gc_implementation/shared/markSweep.inline.hpp"
27 #include "interpreter/interpreter.hpp"
28 #include "interpreter/rewriter.hpp"
29 #include "memory/universe.inline.hpp"
30 #include "oops/cpCacheOop.hpp"
31 #include "oops/objArrayOop.hpp"
32 #include "oops/oop.inline.hpp"
33 #include "prims/jvmtiRedefineClassesTrace.hpp"
34 #include "runtime/handles.inline.hpp"
35
36
37 // Implememtation of ConstantPoolCacheEntry
38
39 void ConstantPoolCacheEntry::initialize_entry(int index) {
40 assert(0 < index && index < 0x10000, "sanity check");
41 _indices = index;
42 assert(constant_pool_index() == index, "");
43 }
44
45 void ConstantPoolCacheEntry::initialize_secondary_entry(int main_index) {
46 assert(0 <= main_index && main_index < 0x10000, "sanity check");
47 _indices = (main_index << 16);
48 assert(main_entry_index() == main_index, "");
49 }
50
51 int ConstantPoolCacheEntry::as_flags(TosState state, bool is_final,
52 bool is_vfinal, bool is_volatile,
53 bool is_method_interface, bool is_method) {
54 int f = state;
55
56 assert( state < number_of_states, "Invalid state in as_flags");
57
58 f <<= 1;
59 if (is_final) f |= 1;
60 f <<= 1;
61 if (is_vfinal) f |= 1;
62 f <<= 1;
63 if (is_volatile) f |= 1;
64 f <<= 1;
65 if (is_method_interface) f |= 1;
66 f <<= 1;
67 if (is_method) f |= 1;
68 f <<= ConstantPoolCacheEntry::hotSwapBit;
69 // Preserve existing flag bit values
70 #ifdef ASSERT
71 int old_state = ((_flags >> tosBits) & 0x0F);
72 assert(old_state == 0 || old_state == state,
73 "inconsistent cpCache flags state");
74 #endif
75 return (_flags | f) ;
76 }
77
78 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
79 #ifdef ASSERT
80 // Read once.
81 volatile Bytecodes::Code c = bytecode_1();
82 assert(c == 0 || c == code || code == 0, "update must be consistent");
83 #endif
84 // Need to flush pending stores here before bytecode is written.
85 OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << 16));
86 }
87
88 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
89 #ifdef ASSERT
90 // Read once.
91 volatile Bytecodes::Code c = bytecode_2();
92 assert(c == 0 || c == code || code == 0, "update must be consistent");
93 #endif
94 // Need to flush pending stores here before bytecode is written.
95 OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << 24));
96 }
97
98 #ifdef ASSERT
99 // It is possible to have two different dummy methodOops created
100 // when the resolve code for invoke interface executes concurrently
101 // Hence the assertion below is weakened a bit for the invokeinterface
102 // case.
103 bool ConstantPoolCacheEntry::same_methodOop(oop cur_f1, oop f1) {
104 return (cur_f1 == f1 || ((methodOop)cur_f1)->name() ==
105 ((methodOop)f1)->name() || ((methodOop)cur_f1)->signature() ==
106 ((methodOop)f1)->signature());
107 }
108 #endif
109
110 // Note that concurrent update of both bytecodes can leave one of them
111 // reset to zero. This is harmless; the interpreter will simply re-resolve
112 // the damaged entry. More seriously, the memory synchronization is needed
113 // to flush other fields (f1, f2) completely to memory before the bytecodes
114 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
115 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
116 Bytecodes::Code put_code,
117 KlassHandle field_holder,
118 int orig_field_index,
119 int field_offset,
120 TosState field_type,
121 bool is_final,
122 bool is_volatile) {
123 set_f1(field_holder());
124 set_f2(field_offset);
125 // The field index is used by jvm/ti and is the index into fields() array
126 // in holder instanceKlass. This is scaled by instanceKlass::next_offset.
127 assert((orig_field_index % instanceKlass::next_offset) == 0, "wierd index");
128 const int field_index = orig_field_index / instanceKlass::next_offset;
129 assert(field_index <= field_index_mask,
130 "field index does not fit in low flag bits");
131 set_flags(as_flags(field_type, is_final, false, is_volatile, false, false) |
132 (field_index & field_index_mask));
133 set_bytecode_1(get_code);
134 set_bytecode_2(put_code);
135 NOT_PRODUCT(verify(tty));
136 }
137
138 int ConstantPoolCacheEntry::field_index() const {
139 return (_flags & field_index_mask) * instanceKlass::next_offset;
140 }
141
142 void ConstantPoolCacheEntry::set_method(Bytecodes::Code invoke_code,
143 methodHandle method,
144 int vtable_index) {
145 assert(!is_secondary_entry(), "");
146 assert(method->interpreter_entry() != NULL, "should have been set at this point");
147 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
148 bool change_to_virtual = (invoke_code == Bytecodes::_invokeinterface);
149
150 int byte_no = -1;
151 bool needs_vfinal_flag = false;
152 switch (invoke_code) {
153 case Bytecodes::_invokevirtual:
154 case Bytecodes::_invokeinterface: {
155 if (method->can_be_statically_bound()) {
156 set_f2((intptr_t)method());
157 needs_vfinal_flag = true;
158 } else {
159 assert(vtable_index >= 0, "valid index");
160 set_f2(vtable_index);
161 }
162 byte_no = 2;
163 break;
164 }
165
166 case Bytecodes::_invokedynamic: // similar to _invokevirtual
167 if (TraceInvokeDynamic) {
168 tty->print_cr("InvokeDynamic set_method%s method="PTR_FORMAT" index=%d",
169 (is_secondary_entry() ? " secondary" : ""),
170 (intptr_t)method(), vtable_index);
171 method->print();
172 this->print(tty, 0);
173 }
174 assert(method->can_be_statically_bound(), "must be a MH invoker method");
175 assert(AllowTransitionalJSR292 || _f2 >= constantPoolOopDesc::CPCACHE_INDEX_TAG, "BSM index initialized");
176 set_f1(method());
177 needs_vfinal_flag = false; // _f2 is not an oop
178 assert(!is_vfinal(), "f2 not an oop");
179 byte_no = 1; // coordinate this with bytecode_number & is_resolved
180 break;
181
182 case Bytecodes::_invokespecial:
183 // Preserve the value of the vfinal flag on invokevirtual bytecode
184 // which may be shared with this constant pool cache entry.
185 needs_vfinal_flag = is_resolved(Bytecodes::_invokevirtual) && is_vfinal();
186 // fall through
187 case Bytecodes::_invokestatic:
188 set_f1(method());
189 byte_no = 1;
190 break;
191 default:
192 ShouldNotReachHere();
193 break;
194 }
195
196 set_flags(as_flags(as_TosState(method->result_type()),
197 method->is_final_method(),
198 needs_vfinal_flag,
199 false,
200 change_to_virtual,
201 true)|
202 method()->size_of_parameters());
203
204 // Note: byte_no also appears in TemplateTable::resolve.
205 if (byte_no == 1) {
206 set_bytecode_1(invoke_code);
207 } else if (byte_no == 2) {
208 if (change_to_virtual) {
209 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
210 //
211 // Workaround for the case where we encounter an invokeinterface, but we
212 // should really have an _invokevirtual since the resolved method is a
213 // virtual method in java.lang.Object. This is a corner case in the spec
214 // but is presumably legal. javac does not generate this code.
215 //
216 // We set bytecode_1() to _invokeinterface, because that is the
217 // bytecode # used by the interpreter to see if it is resolved.
218 // We set bytecode_2() to _invokevirtual.
219 // See also interpreterRuntime.cpp. (8/25/2000)
220 // Only set resolved for the invokeinterface case if method is public.
221 // Otherwise, the method needs to be reresolved with caller for each
222 // interface call.
223 if (method->is_public()) set_bytecode_1(invoke_code);
224 set_bytecode_2(Bytecodes::_invokevirtual);
225 } else {
226 set_bytecode_2(invoke_code);
227 }
228 } else {
229 ShouldNotReachHere();
230 }
231 NOT_PRODUCT(verify(tty));
232 }
233
234
235 void ConstantPoolCacheEntry::set_interface_call(methodHandle method, int index) {
236 assert(!is_secondary_entry(), "");
237 klassOop interf = method->method_holder();
238 assert(instanceKlass::cast(interf)->is_interface(), "must be an interface");
239 set_f1(interf);
240 set_f2(index);
241 set_flags(as_flags(as_TosState(method->result_type()), method->is_final_method(), false, false, false, true) | method()->size_of_parameters());
242 set_bytecode_1(Bytecodes::_invokeinterface);
243 }
244
245
246 void ConstantPoolCacheEntry::initialize_bootstrap_method_index_in_cache(int bsm_cache_index) {
247 assert(!is_secondary_entry(), "only for JVM_CONSTANT_InvokeDynamic main entry");
248 assert(_f2 == 0, "initialize once");
249 assert(bsm_cache_index == (int)(u2)bsm_cache_index, "oob");
250 set_f2(bsm_cache_index + constantPoolOopDesc::CPCACHE_INDEX_TAG);
251 }
252
253 int ConstantPoolCacheEntry::bootstrap_method_index_in_cache() {
254 assert(!is_secondary_entry(), "only for JVM_CONSTANT_InvokeDynamic main entry");
255 intptr_t bsm_cache_index = (intptr_t) _f2 - constantPoolOopDesc::CPCACHE_INDEX_TAG;
256 assert(bsm_cache_index == (intptr_t)(u2)bsm_cache_index, "oob");
257 return (int) bsm_cache_index;
258 }
259
260 void ConstantPoolCacheEntry::set_dynamic_call(Handle call_site,
261 methodHandle signature_invoker) {
262 assert(is_secondary_entry(), "");
263 int param_size = signature_invoker->size_of_parameters();
264 assert(param_size >= 1, "method argument size must include MH.this");
265 param_size -= 1; // do not count MH.this; it is not stacked for invokedynamic
266 if (Atomic::cmpxchg_ptr(call_site(), &_f1, NULL) == NULL) {
267 // racing threads might be trying to install their own favorites
268 set_f1(call_site());
269 }
270 bool is_final = true;
271 assert(signature_invoker->is_final_method(), "is_final");
272 set_flags(as_flags(as_TosState(signature_invoker->result_type()), is_final, false, false, false, true) | param_size);
273 // do not do set_bytecode on a secondary CP cache entry
274 //set_bytecode_1(Bytecodes::_invokedynamic);
275 }
276
277
278 class LocalOopClosure: public OopClosure {
279 private:
280 void (*_f)(oop*);
281
282 public:
283 LocalOopClosure(void f(oop*)) { _f = f; }
284 virtual void do_oop(oop* o) { _f(o); }
285 virtual void do_oop(narrowOop *o) { ShouldNotReachHere(); }
286 };
287
288
289 void ConstantPoolCacheEntry::oops_do(void f(oop*)) {
290 LocalOopClosure blk(f);
291 oop_iterate(&blk);
292 }
293
294
295 void ConstantPoolCacheEntry::oop_iterate(OopClosure* blk) {
296 assert(in_words(size()) == 4, "check code below - may need adjustment");
297 // field[1] is always oop or NULL
298 blk->do_oop((oop*)&_f1);
299 if (is_vfinal()) {
300 blk->do_oop((oop*)&_f2);
301 }
302 }
303
304
305 void ConstantPoolCacheEntry::oop_iterate_m(OopClosure* blk, MemRegion mr) {
306 assert(in_words(size()) == 4, "check code below - may need adjustment");
307 // field[1] is always oop or NULL
308 if (mr.contains((oop *)&_f1)) blk->do_oop((oop*)&_f1);
309 if (is_vfinal()) {
310 if (mr.contains((oop *)&_f2)) blk->do_oop((oop*)&_f2);
311 }
312 }
313
314
315 void ConstantPoolCacheEntry::follow_contents() {
316 assert(in_words(size()) == 4, "check code below - may need adjustment");
317 // field[1] is always oop or NULL
318 MarkSweep::mark_and_push((oop*)&_f1);
319 if (is_vfinal()) {
320 MarkSweep::mark_and_push((oop*)&_f2);
321 }
322 }
323
324 #ifndef SERIALGC
325 void ConstantPoolCacheEntry::follow_contents(ParCompactionManager* cm) {
326 assert(in_words(size()) == 4, "check code below - may need adjustment");
327 // field[1] is always oop or NULL
328 PSParallelCompact::mark_and_push(cm, (oop*)&_f1);
329 if (is_vfinal()) {
330 PSParallelCompact::mark_and_push(cm, (oop*)&_f2);
331 }
332 }
333 #endif // SERIALGC
334
335 void ConstantPoolCacheEntry::adjust_pointers() {
336 assert(in_words(size()) == 4, "check code below - may need adjustment");
337 // field[1] is always oop or NULL
338 MarkSweep::adjust_pointer((oop*)&_f1);
339 if (is_vfinal()) {
340 MarkSweep::adjust_pointer((oop*)&_f2);
341 }
342 }
343
344 #ifndef SERIALGC
345 void ConstantPoolCacheEntry::update_pointers() {
346 assert(in_words(size()) == 4, "check code below - may need adjustment");
347 // field[1] is always oop or NULL
348 PSParallelCompact::adjust_pointer((oop*)&_f1);
349 if (is_vfinal()) {
350 PSParallelCompact::adjust_pointer((oop*)&_f2);
351 }
352 }
353
354 void ConstantPoolCacheEntry::update_pointers(HeapWord* beg_addr,
355 HeapWord* end_addr) {
356 assert(in_words(size()) == 4, "check code below - may need adjustment");
357 // field[1] is always oop or NULL
358 PSParallelCompact::adjust_pointer((oop*)&_f1, beg_addr, end_addr);
359 if (is_vfinal()) {
360 PSParallelCompact::adjust_pointer((oop*)&_f2, beg_addr, end_addr);
361 }
362 }
363 #endif // SERIALGC
364
365 // RedefineClasses() API support:
366 // If this constantPoolCacheEntry refers to old_method then update it
367 // to refer to new_method.
368 bool ConstantPoolCacheEntry::adjust_method_entry(methodOop old_method,
369 methodOop new_method, bool * trace_name_printed) {
370
371 if (is_vfinal()) {
372 // virtual and final so f2() contains method ptr instead of vtable index
373 if (f2() == (intptr_t)old_method) {
374 // match old_method so need an update
375 _f2 = (intptr_t)new_method;
376 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
377 if (!(*trace_name_printed)) {
378 // RC_TRACE_MESG macro has an embedded ResourceMark
379 RC_TRACE_MESG(("adjust: name=%s",
380 Klass::cast(old_method->method_holder())->external_name()));
381 *trace_name_printed = true;
382 }
383 // RC_TRACE macro has an embedded ResourceMark
384 RC_TRACE(0x00400000, ("cpc vf-entry update: %s(%s)",
385 new_method->name()->as_C_string(),
386 new_method->signature()->as_C_string()));
387 }
388
389 return true;
390 }
391
392 // f1() is not used with virtual entries so bail out
393 return false;
394 }
395
396 if ((oop)_f1 == NULL) {
397 // NULL f1() means this is a virtual entry so bail out
398 // We are assuming that the vtable index does not need change.
399 return false;
400 }
401
402 if ((oop)_f1 == old_method) {
403 _f1 = new_method;
404 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
405 if (!(*trace_name_printed)) {
406 // RC_TRACE_MESG macro has an embedded ResourceMark
407 RC_TRACE_MESG(("adjust: name=%s",
408 Klass::cast(old_method->method_holder())->external_name()));
409 *trace_name_printed = true;
410 }
411 // RC_TRACE macro has an embedded ResourceMark
412 RC_TRACE(0x00400000, ("cpc entry update: %s(%s)",
413 new_method->name()->as_C_string(),
414 new_method->signature()->as_C_string()));
415 }
416
417 return true;
418 }
419
420 return false;
421 }
422
423 bool ConstantPoolCacheEntry::is_interesting_method_entry(klassOop k) {
424 if (!is_method_entry()) {
425 // not a method entry so not interesting by default
426 return false;
427 }
428
429 methodOop m = NULL;
430 if (is_vfinal()) {
431 // virtual and final so _f2 contains method ptr instead of vtable index
432 m = (methodOop)_f2;
433 } else if ((oop)_f1 == NULL) {
434 // NULL _f1 means this is a virtual entry so also not interesting
435 return false;
436 } else {
437 if (!((oop)_f1)->is_method()) {
438 // _f1 can also contain a klassOop for an interface
439 return false;
440 }
441 m = (methodOop)_f1;
442 }
443
444 assert(m != NULL && m->is_method(), "sanity check");
445 if (m == NULL || !m->is_method() || m->method_holder() != k) {
446 // robustness for above sanity checks or method is not in
447 // the interesting class
448 return false;
449 }
450
451 // the method is in the interesting class so the entry is interesting
452 return true;
453 }
454
455 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
456 // print separator
457 if (index == 0) tty->print_cr(" -------------");
458 // print entry
459 tty->print("%3d ("PTR_FORMAT") ", index, (intptr_t)this);
460 if (is_secondary_entry())
461 tty->print_cr("[%5d|secondary]", main_entry_index());
462 else
463 tty->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(), constant_pool_index());
464 tty->print_cr(" [ "PTR_FORMAT"]", (intptr_t)(oop)_f1);
465 tty->print_cr(" [ "PTR_FORMAT"]", (intptr_t)_f2);
466 tty->print_cr(" [ "PTR_FORMAT"]", (intptr_t)_flags);
467 tty->print_cr(" -------------");
468 }
469
470 void ConstantPoolCacheEntry::verify(outputStream* st) const {
471 // not implemented yet
472 }
473
474 // Implementation of ConstantPoolCache
475
476 void constantPoolCacheOopDesc::initialize(intArray& inverse_index_map) {
477 assert(inverse_index_map.length() == length(), "inverse index map must have same length as cache");
478 for (int i = 0; i < length(); i++) {
479 ConstantPoolCacheEntry* e = entry_at(i);
480 int original_index = inverse_index_map[i];
481 if ((original_index & Rewriter::_secondary_entry_tag) != 0) {
482 int main_index = (original_index - Rewriter::_secondary_entry_tag);
483 assert(!entry_at(main_index)->is_secondary_entry(), "valid main index");
484 e->initialize_secondary_entry(main_index);
485 } else {
486 e->initialize_entry(original_index);
487 }
488 assert(entry_at(i) == e, "sanity");
489 }
490 }
491
492 // RedefineClasses() API support:
493 // If any entry of this constantPoolCache points to any of
494 // old_methods, replace it with the corresponding new_method.
495 void constantPoolCacheOopDesc::adjust_method_entries(methodOop* old_methods, methodOop* new_methods,
496 int methods_length, bool * trace_name_printed) {
497
498 if (methods_length == 0) {
499 // nothing to do if there are no methods
500 return;
501 }
502
503 // get shorthand for the interesting class
504 klassOop old_holder = old_methods[0]->method_holder();
505
506 for (int i = 0; i < length(); i++) {
507 if (!entry_at(i)->is_interesting_method_entry(old_holder)) {
508 // skip uninteresting methods
509 continue;
510 }
511
512 // The constantPoolCache contains entries for several different
513 // things, but we only care about methods. In fact, we only care
514 // about methods in the same class as the one that contains the
515 // old_methods. At this point, we have an interesting entry.
516
517 for (int j = 0; j < methods_length; j++) {
518 methodOop old_method = old_methods[j];
519 methodOop new_method = new_methods[j];
520
521 if (entry_at(i)->adjust_method_entry(old_method, new_method,
522 trace_name_printed)) {
523 // current old_method matched this entry and we updated it so
524 // break out and get to the next interesting entry if there one
525 break;
526 }
527 }
528 }
529 }