1 /*
2 * Copyright (c) 1998, 2009, 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.
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23 */
24
25 #include "incls/_precompiled.incl"
26 #include "incls/_cpCacheOop.cpp.incl"
27
28
29 // Implememtation of ConstantPoolCacheEntry
30
31 void ConstantPoolCacheEntry::initialize_entry(int index) {
32 assert(0 < index && index < 0x10000, "sanity check");
33 _indices = index;
34 assert(constant_pool_index() == index, "");
35 }
36
37 void ConstantPoolCacheEntry::initialize_secondary_entry(int main_index) {
38 assert(0 <= main_index && main_index < 0x10000, "sanity check");
39 _indices = (main_index << 16);
40 assert(main_entry_index() == main_index, "");
41 }
42
43 int ConstantPoolCacheEntry::as_flags(TosState state, bool is_final,
44 bool is_vfinal, bool is_volatile,
45 bool is_method_interface, bool is_method) {
46 int f = state;
47
48 assert( state < number_of_states, "Invalid state in as_flags");
49
50 f <<= 1;
51 if (is_final) f |= 1;
52 f <<= 1;
53 if (is_vfinal) f |= 1;
54 f <<= 1;
55 if (is_volatile) f |= 1;
56 f <<= 1;
57 if (is_method_interface) f |= 1;
58 f <<= 1;
59 if (is_method) f |= 1;
60 f <<= ConstantPoolCacheEntry::hotSwapBit;
61 // Preserve existing flag bit values
62 #ifdef ASSERT
63 int old_state = ((_flags >> tosBits) & 0x0F);
64 assert(old_state == 0 || old_state == state,
65 "inconsistent cpCache flags state");
66 #endif
67 return (_flags | f) ;
68 }
69
70 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
71 #ifdef ASSERT
72 // Read once.
73 volatile Bytecodes::Code c = bytecode_1();
74 assert(c == 0 || c == code || code == 0, "update must be consistent");
75 #endif
76 // Need to flush pending stores here before bytecode is written.
77 OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << 16));
78 }
79
80 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
81 #ifdef ASSERT
82 // Read once.
83 volatile Bytecodes::Code c = bytecode_2();
84 assert(c == 0 || c == code || code == 0, "update must be consistent");
85 #endif
86 // Need to flush pending stores here before bytecode is written.
87 OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << 24));
88 }
89
90 #ifdef ASSERT
91 // It is possible to have two different dummy methodOops created
92 // when the resolve code for invoke interface executes concurrently
93 // Hence the assertion below is weakened a bit for the invokeinterface
94 // case.
95 bool ConstantPoolCacheEntry::same_methodOop(oop cur_f1, oop f1) {
96 return (cur_f1 == f1 || ((methodOop)cur_f1)->name() ==
97 ((methodOop)f1)->name() || ((methodOop)cur_f1)->signature() ==
98 ((methodOop)f1)->signature());
99 }
100 #endif
101
102 // Note that concurrent update of both bytecodes can leave one of them
103 // reset to zero. This is harmless; the interpreter will simply re-resolve
104 // the damaged entry. More seriously, the memory synchronization is needed
105 // to flush other fields (f1, f2) completely to memory before the bytecodes
106 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
107 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
108 Bytecodes::Code put_code,
109 KlassHandle field_holder,
110 int orig_field_index,
111 int field_offset,
112 TosState field_type,
113 bool is_final,
114 bool is_volatile) {
115 set_f1(field_holder());
116 set_f2(field_offset);
117 // The field index is used by jvm/ti and is the index into fields() array
118 // in holder instanceKlass. This is scaled by instanceKlass::next_offset.
119 assert((orig_field_index % instanceKlass::next_offset) == 0, "wierd index");
120 const int field_index = orig_field_index / instanceKlass::next_offset;
121 assert(field_index <= field_index_mask,
122 "field index does not fit in low flag bits");
123 set_flags(as_flags(field_type, is_final, false, is_volatile, false, false) |
124 (field_index & field_index_mask));
125 set_bytecode_1(get_code);
126 set_bytecode_2(put_code);
127 NOT_PRODUCT(verify(tty));
128 }
129
130 int ConstantPoolCacheEntry::field_index() const {
131 return (_flags & field_index_mask) * instanceKlass::next_offset;
132 }
133
134 void ConstantPoolCacheEntry::set_method(Bytecodes::Code invoke_code,
135 methodHandle method,
136 int vtable_index) {
137 assert(!is_secondary_entry(), "");
138 assert(method->interpreter_entry() != NULL, "should have been set at this point");
139 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
140 bool change_to_virtual = (invoke_code == Bytecodes::_invokeinterface);
141
142 int byte_no = -1;
143 bool needs_vfinal_flag = false;
144 switch (invoke_code) {
145 case Bytecodes::_invokevirtual:
146 case Bytecodes::_invokeinterface: {
147 if (method->can_be_statically_bound()) {
148 set_f2((intptr_t)method());
149 needs_vfinal_flag = true;
150 } else {
151 assert(vtable_index >= 0, "valid index");
152 set_f2(vtable_index);
153 }
154 byte_no = 2;
155 break;
156 }
157
158 case Bytecodes::_invokedynamic: // similar to _invokevirtual
159 if (TraceInvokeDynamic) {
160 tty->print_cr("InvokeDynamic set_method%s method="PTR_FORMAT" index=%d",
161 (is_secondary_entry() ? " secondary" : ""),
162 (intptr_t)method(), vtable_index);
163 method->print();
164 this->print(tty, 0);
165 }
166 assert(method->can_be_statically_bound(), "must be a MH invoker method");
167 assert(AllowTransitionalJSR292 || _f2 >= constantPoolOopDesc::CPCACHE_INDEX_TAG, "BSM index initialized");
168 set_f1(method());
169 needs_vfinal_flag = false; // _f2 is not an oop
170 assert(!is_vfinal(), "f2 not an oop");
171 byte_no = 1; // coordinate this with bytecode_number & is_resolved
172 break;
173
174 case Bytecodes::_invokespecial:
175 // Preserve the value of the vfinal flag on invokevirtual bytecode
176 // which may be shared with this constant pool cache entry.
177 needs_vfinal_flag = is_resolved(Bytecodes::_invokevirtual) && is_vfinal();
178 // fall through
179 case Bytecodes::_invokestatic:
180 set_f1(method());
181 byte_no = 1;
182 break;
183 default:
184 ShouldNotReachHere();
185 break;
186 }
187
188 set_flags(as_flags(as_TosState(method->result_type()),
189 method->is_final_method(),
190 needs_vfinal_flag,
191 false,
192 change_to_virtual,
193 true)|
194 method()->size_of_parameters());
195
196 // Note: byte_no also appears in TemplateTable::resolve.
197 if (byte_no == 1) {
198 set_bytecode_1(invoke_code);
199 } else if (byte_no == 2) {
200 if (change_to_virtual) {
201 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
202 //
203 // Workaround for the case where we encounter an invokeinterface, but we
204 // should really have an _invokevirtual since the resolved method is a
205 // virtual method in java.lang.Object. This is a corner case in the spec
206 // but is presumably legal. javac does not generate this code.
207 //
208 // We set bytecode_1() to _invokeinterface, because that is the
209 // bytecode # used by the interpreter to see if it is resolved.
210 // We set bytecode_2() to _invokevirtual.
211 // See also interpreterRuntime.cpp. (8/25/2000)
212 // Only set resolved for the invokeinterface case if method is public.
213 // Otherwise, the method needs to be reresolved with caller for each
214 // interface call.
215 if (method->is_public()) set_bytecode_1(invoke_code);
216 set_bytecode_2(Bytecodes::_invokevirtual);
217 } else {
218 set_bytecode_2(invoke_code);
219 }
220 } else {
221 ShouldNotReachHere();
222 }
223 NOT_PRODUCT(verify(tty));
224 }
225
226
227 void ConstantPoolCacheEntry::set_interface_call(methodHandle method, int index) {
228 assert(!is_secondary_entry(), "");
229 klassOop interf = method->method_holder();
230 assert(instanceKlass::cast(interf)->is_interface(), "must be an interface");
231 set_f1(interf);
232 set_f2(index);
233 set_flags(as_flags(as_TosState(method->result_type()), method->is_final_method(), false, false, false, true) | method()->size_of_parameters());
234 set_bytecode_1(Bytecodes::_invokeinterface);
235 }
236
237
238 void ConstantPoolCacheEntry::initialize_bootstrap_method_index_in_cache(int bsm_cache_index) {
239 assert(!is_secondary_entry(), "only for JVM_CONSTANT_InvokeDynamic main entry");
240 assert(_f2 == 0, "initialize once");
241 assert(bsm_cache_index == (int)(u2)bsm_cache_index, "oob");
242 set_f2(bsm_cache_index + constantPoolOopDesc::CPCACHE_INDEX_TAG);
243 }
244
245 int ConstantPoolCacheEntry::bootstrap_method_index_in_cache() {
246 assert(!is_secondary_entry(), "only for JVM_CONSTANT_InvokeDynamic main entry");
247 intptr_t bsm_cache_index = (intptr_t) _f2 - constantPoolOopDesc::CPCACHE_INDEX_TAG;
248 assert(bsm_cache_index == (intptr_t)(u2)bsm_cache_index, "oob");
249 return (int) bsm_cache_index;
250 }
251
252 void ConstantPoolCacheEntry::set_dynamic_call(Handle call_site,
253 methodHandle signature_invoker) {
254 assert(is_secondary_entry(), "");
255 int param_size = signature_invoker->size_of_parameters();
256 assert(param_size >= 1, "method argument size must include MH.this");
257 param_size -= 1; // do not count MH.this; it is not stacked for invokedynamic
258 if (Atomic::cmpxchg_ptr(call_site(), &_f1, NULL) == NULL) {
259 // racing threads might be trying to install their own favorites
260 set_f1(call_site());
261 }
262 bool is_final = true;
263 assert(signature_invoker->is_final_method(), "is_final");
264 set_flags(as_flags(as_TosState(signature_invoker->result_type()), is_final, false, false, false, true) | param_size);
265 // do not do set_bytecode on a secondary CP cache entry
266 //set_bytecode_1(Bytecodes::_invokedynamic);
267 }
268
269
270 class LocalOopClosure: public OopClosure {
271 private:
272 void (*_f)(oop*);
273
274 public:
275 LocalOopClosure(void f(oop*)) { _f = f; }
276 virtual void do_oop(oop* o) { _f(o); }
277 virtual void do_oop(narrowOop *o) { ShouldNotReachHere(); }
278 };
279
280
281 void ConstantPoolCacheEntry::oops_do(void f(oop*)) {
282 LocalOopClosure blk(f);
283 oop_iterate(&blk);
284 }
285
286
287 void ConstantPoolCacheEntry::oop_iterate(OopClosure* blk) {
288 assert(in_words(size()) == 4, "check code below - may need adjustment");
289 // field[1] is always oop or NULL
290 blk->do_oop((oop*)&_f1);
291 if (is_vfinal()) {
292 blk->do_oop((oop*)&_f2);
293 }
294 }
295
296
297 void ConstantPoolCacheEntry::oop_iterate_m(OopClosure* blk, MemRegion mr) {
298 assert(in_words(size()) == 4, "check code below - may need adjustment");
299 // field[1] is always oop or NULL
300 if (mr.contains((oop *)&_f1)) blk->do_oop((oop*)&_f1);
301 if (is_vfinal()) {
302 if (mr.contains((oop *)&_f2)) blk->do_oop((oop*)&_f2);
303 }
304 }
305
306
307 void ConstantPoolCacheEntry::follow_contents() {
308 assert(in_words(size()) == 4, "check code below - may need adjustment");
309 // field[1] is always oop or NULL
310 MarkSweep::mark_and_push((oop*)&_f1);
311 if (is_vfinal()) {
312 MarkSweep::mark_and_push((oop*)&_f2);
313 }
314 }
315
316 #ifndef SERIALGC
317 void ConstantPoolCacheEntry::follow_contents(ParCompactionManager* cm) {
318 assert(in_words(size()) == 4, "check code below - may need adjustment");
319 // field[1] is always oop or NULL
320 PSParallelCompact::mark_and_push(cm, (oop*)&_f1);
321 if (is_vfinal()) {
322 PSParallelCompact::mark_and_push(cm, (oop*)&_f2);
323 }
324 }
325 #endif // SERIALGC
326
327 void ConstantPoolCacheEntry::adjust_pointers() {
328 assert(in_words(size()) == 4, "check code below - may need adjustment");
329 // field[1] is always oop or NULL
330 MarkSweep::adjust_pointer((oop*)&_f1);
331 if (is_vfinal()) {
332 MarkSweep::adjust_pointer((oop*)&_f2);
333 }
334 }
335
336 #ifndef SERIALGC
337 void ConstantPoolCacheEntry::update_pointers() {
338 assert(in_words(size()) == 4, "check code below - may need adjustment");
339 // field[1] is always oop or NULL
340 PSParallelCompact::adjust_pointer((oop*)&_f1);
341 if (is_vfinal()) {
342 PSParallelCompact::adjust_pointer((oop*)&_f2);
343 }
344 }
345
346 void ConstantPoolCacheEntry::update_pointers(HeapWord* beg_addr,
347 HeapWord* end_addr) {
348 assert(in_words(size()) == 4, "check code below - may need adjustment");
349 // field[1] is always oop or NULL
350 PSParallelCompact::adjust_pointer((oop*)&_f1, beg_addr, end_addr);
351 if (is_vfinal()) {
352 PSParallelCompact::adjust_pointer((oop*)&_f2, beg_addr, end_addr);
353 }
354 }
355 #endif // SERIALGC
356
357 // RedefineClasses() API support:
358 // If this constantPoolCacheEntry refers to old_method then update it
359 // to refer to new_method.
360 bool ConstantPoolCacheEntry::adjust_method_entry(methodOop old_method,
361 methodOop new_method, bool * trace_name_printed) {
362
363 if (is_vfinal()) {
364 // virtual and final so f2() contains method ptr instead of vtable index
365 if (f2() == (intptr_t)old_method) {
366 // match old_method so need an update
367 _f2 = (intptr_t)new_method;
368 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
369 if (!(*trace_name_printed)) {
370 // RC_TRACE_MESG macro has an embedded ResourceMark
371 RC_TRACE_MESG(("adjust: name=%s",
372 Klass::cast(old_method->method_holder())->external_name()));
373 *trace_name_printed = true;
374 }
375 // RC_TRACE macro has an embedded ResourceMark
376 RC_TRACE(0x00400000, ("cpc vf-entry update: %s(%s)",
377 new_method->name()->as_C_string(),
378 new_method->signature()->as_C_string()));
379 }
380
381 return true;
382 }
383
384 // f1() is not used with virtual entries so bail out
385 return false;
386 }
387
388 if ((oop)_f1 == NULL) {
389 // NULL f1() means this is a virtual entry so bail out
390 // We are assuming that the vtable index does not need change.
391 return false;
392 }
393
394 if ((oop)_f1 == old_method) {
395 _f1 = new_method;
396 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
397 if (!(*trace_name_printed)) {
398 // RC_TRACE_MESG macro has an embedded ResourceMark
399 RC_TRACE_MESG(("adjust: name=%s",
400 Klass::cast(old_method->method_holder())->external_name()));
401 *trace_name_printed = true;
402 }
403 // RC_TRACE macro has an embedded ResourceMark
404 RC_TRACE(0x00400000, ("cpc entry update: %s(%s)",
405 new_method->name()->as_C_string(),
406 new_method->signature()->as_C_string()));
407 }
408
409 return true;
410 }
411
412 return false;
413 }
414
415 bool ConstantPoolCacheEntry::is_interesting_method_entry(klassOop k) {
416 if (!is_method_entry()) {
417 // not a method entry so not interesting by default
418 return false;
419 }
420
421 methodOop m = NULL;
422 if (is_vfinal()) {
423 // virtual and final so _f2 contains method ptr instead of vtable index
424 m = (methodOop)_f2;
425 } else if ((oop)_f1 == NULL) {
426 // NULL _f1 means this is a virtual entry so also not interesting
427 return false;
428 } else {
429 if (!((oop)_f1)->is_method()) {
430 // _f1 can also contain a klassOop for an interface
431 return false;
432 }
433 m = (methodOop)_f1;
434 }
435
436 assert(m != NULL && m->is_method(), "sanity check");
437 if (m == NULL || !m->is_method() || m->method_holder() != k) {
438 // robustness for above sanity checks or method is not in
439 // the interesting class
440 return false;
441 }
442
443 // the method is in the interesting class so the entry is interesting
444 return true;
445 }
446
447 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
448 // print separator
449 if (index == 0) tty->print_cr(" -------------");
450 // print entry
451 tty->print("%3d ("PTR_FORMAT") ", index, (intptr_t)this);
452 if (is_secondary_entry())
453 tty->print_cr("[%5d|secondary]", main_entry_index());
454 else
455 tty->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(), constant_pool_index());
456 tty->print_cr(" [ "PTR_FORMAT"]", (intptr_t)(oop)_f1);
457 tty->print_cr(" [ "PTR_FORMAT"]", (intptr_t)_f2);
458 tty->print_cr(" [ "PTR_FORMAT"]", (intptr_t)_flags);
459 tty->print_cr(" -------------");
460 }
461
462 void ConstantPoolCacheEntry::verify(outputStream* st) const {
463 // not implemented yet
464 }
465
466 // Implementation of ConstantPoolCache
467
468 void constantPoolCacheOopDesc::initialize(intArray& inverse_index_map) {
469 assert(inverse_index_map.length() == length(), "inverse index map must have same length as cache");
470 for (int i = 0; i < length(); i++) {
471 ConstantPoolCacheEntry* e = entry_at(i);
472 int original_index = inverse_index_map[i];
473 if ((original_index & Rewriter::_secondary_entry_tag) != 0) {
474 int main_index = (original_index - Rewriter::_secondary_entry_tag);
475 assert(!entry_at(main_index)->is_secondary_entry(), "valid main index");
476 e->initialize_secondary_entry(main_index);
477 } else {
478 e->initialize_entry(original_index);
479 }
480 assert(entry_at(i) == e, "sanity");
481 }
482 }
483
484 // RedefineClasses() API support:
485 // If any entry of this constantPoolCache points to any of
486 // old_methods, replace it with the corresponding new_method.
487 void constantPoolCacheOopDesc::adjust_method_entries(methodOop* old_methods, methodOop* new_methods,
488 int methods_length, bool * trace_name_printed) {
489
490 if (methods_length == 0) {
491 // nothing to do if there are no methods
492 return;
493 }
494
495 // get shorthand for the interesting class
496 klassOop old_holder = old_methods[0]->method_holder();
497
498 for (int i = 0; i < length(); i++) {
499 if (!entry_at(i)->is_interesting_method_entry(old_holder)) {
500 // skip uninteresting methods
501 continue;
502 }
503
504 // The constantPoolCache contains entries for several different
505 // things, but we only care about methods. In fact, we only care
506 // about methods in the same class as the one that contains the
507 // old_methods. At this point, we have an interesting entry.
508
509 for (int j = 0; j < methods_length; j++) {
510 methodOop old_method = old_methods[j];
511 methodOop new_method = new_methods[j];
512
513 if (entry_at(i)->adjust_method_entry(old_method, new_method,
514 trace_name_printed)) {
515 // current old_method matched this entry and we updated it so
516 // break out and get to the next interesting entry if there one
517 break;
518 }
519 }
520 }
521 }