1 /*
2 * Copyright (c) 1997, 2019, 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 "classfile/classLoaderDataGraph.hpp"
27 #include "classfile/metadataOnStackMark.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "code/codeCache.hpp"
30 #include "code/debugInfoRec.hpp"
31 #include "gc/shared/collectedHeap.inline.hpp"
32 #include "interpreter/bytecodeStream.hpp"
33 #include "interpreter/bytecodeTracer.hpp"
34 #include "interpreter/bytecodes.hpp"
35 #include "interpreter/interpreter.hpp"
36 #include "interpreter/oopMapCache.hpp"
37 #include "memory/allocation.inline.hpp"
38 #include "memory/heapInspection.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/metaspaceClosure.hpp"
41 #include "memory/metaspaceShared.hpp"
42 #include "memory/oopFactory.hpp"
43 #include "memory/resourceArea.hpp"
44 #include "oops/constMethod.hpp"
45 #include "oops/constantPool.hpp"
46 #include "oops/method.inline.hpp"
47 #include "oops/methodData.hpp"
48 #include "oops/objArrayOop.inline.hpp"
49 #include "oops/oop.inline.hpp"
50 #include "oops/symbol.hpp"
51 #include "prims/jvmtiExport.hpp"
52 #include "prims/methodHandles.hpp"
53 #include "prims/nativeLookup.hpp"
54 #include "runtime/arguments.hpp"
55 #include "runtime/compilationPolicy.hpp"
56 #include "runtime/frame.inline.hpp"
57 #include "runtime/handles.inline.hpp"
58 #include "runtime/init.hpp"
59 #include "runtime/orderAccess.hpp"
60 #include "runtime/relocator.hpp"
61 #include "runtime/safepointVerifiers.hpp"
62 #include "runtime/sharedRuntime.hpp"
63 #include "runtime/signature.hpp"
64 #include "utilities/align.hpp"
65 #include "utilities/quickSort.hpp"
66 #include "utilities/vmError.hpp"
67 #include "utilities/xmlstream.hpp"
68
69 // Implementation of Method
70
71 Method* Method::allocate(ClassLoaderData* loader_data,
72 int byte_code_size,
73 AccessFlags access_flags,
74 InlineTableSizes* sizes,
75 ConstMethod::MethodType method_type,
76 TRAPS) {
77 assert(!access_flags.is_native() || byte_code_size == 0,
78 "native methods should not contain byte codes");
79 ConstMethod* cm = ConstMethod::allocate(loader_data,
80 byte_code_size,
81 sizes,
82 method_type,
83 CHECK_NULL);
84 int size = Method::size(access_flags.is_native());
85 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
86 }
87
88 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
89 NoSafepointVerifier no_safepoint;
90 set_constMethod(xconst);
91 set_access_flags(access_flags);
92 set_intrinsic_id(vmIntrinsics::_none);
93 set_force_inline(false);
94 set_hidden(false);
95 set_dont_inline(false);
96 set_has_injected_profile(false);
97 set_method_data(NULL);
98 clear_method_counters();
99 set_vtable_index(Method::garbage_vtable_index);
100
101 // Fix and bury in Method*
102 set_interpreter_entry(NULL); // sets i2i entry and from_int
103 set_adapter_entry(NULL);
104 clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i
105
106 if (access_flags.is_native()) {
107 clear_native_function();
108 set_signature_handler(NULL);
109 }
110
111 NOT_PRODUCT(set_compiled_invocation_count(0);)
112 }
113
114 // Release Method*. The nmethod will be gone when we get here because
115 // we've walked the code cache.
116 void Method::deallocate_contents(ClassLoaderData* loader_data) {
117 MetadataFactory::free_metadata(loader_data, constMethod());
118 set_constMethod(NULL);
119 MetadataFactory::free_metadata(loader_data, method_data());
120 set_method_data(NULL);
121 MetadataFactory::free_metadata(loader_data, method_counters());
122 clear_method_counters();
123 // The nmethod will be gone when we get here.
124 if (code() != NULL) _code = NULL;
125 }
126
127 address Method::get_i2c_entry() {
128 assert(adapter() != NULL, "must have");
129 return adapter()->get_i2c_entry();
130 }
131
132 address Method::get_c2i_entry() {
133 assert(adapter() != NULL, "must have");
134 return adapter()->get_c2i_entry();
135 }
136
137 address Method::get_c2i_unverified_entry() {
138 assert(adapter() != NULL, "must have");
139 return adapter()->get_c2i_unverified_entry();
140 }
141
142 char* Method::name_and_sig_as_C_string() const {
143 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
144 }
145
146 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
147 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
148 }
149
150 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
151 const char* klass_name = klass->external_name();
152 int klass_name_len = (int)strlen(klass_name);
153 int method_name_len = method_name->utf8_length();
154 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
155 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
156 strcpy(dest, klass_name);
157 dest[klass_name_len] = '.';
158 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
159 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
160 dest[len] = 0;
161 return dest;
162 }
163
164 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
165 Symbol* klass_name = klass->name();
166 klass_name->as_klass_external_name(buf, size);
167 int len = (int)strlen(buf);
168
169 if (len < size - 1) {
170 buf[len++] = '.';
171
172 method_name->as_C_string(&(buf[len]), size - len);
173 len = (int)strlen(buf);
174
175 signature->as_C_string(&(buf[len]), size - len);
176 }
177
178 return buf;
179 }
180
181 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
182 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
183 // access exception table
184 ExceptionTable table(mh());
185 int length = table.length();
186 // iterate through all entries sequentially
187 constantPoolHandle pool(THREAD, mh->constants());
188 for (int i = 0; i < length; i ++) {
189 //reacquire the table in case a GC happened
190 ExceptionTable table(mh());
191 int beg_bci = table.start_pc(i);
192 int end_bci = table.end_pc(i);
193 assert(beg_bci <= end_bci, "inconsistent exception table");
194 if (beg_bci <= throw_bci && throw_bci < end_bci) {
195 // exception handler bci range covers throw_bci => investigate further
196 int handler_bci = table.handler_pc(i);
197 int klass_index = table.catch_type_index(i);
198 if (klass_index == 0) {
199 return handler_bci;
200 } else if (ex_klass == NULL) {
201 return handler_bci;
202 } else {
203 // we know the exception class => get the constraint class
204 // this may require loading of the constraint class; if verification
205 // fails or some other exception occurs, return handler_bci
206 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
207 assert(k != NULL, "klass not loaded");
208 if (ex_klass->is_subtype_of(k)) {
209 return handler_bci;
210 }
211 }
212 }
213 }
214
215 return -1;
216 }
217
218 void Method::mask_for(int bci, InterpreterOopMap* mask) {
219 methodHandle h_this(Thread::current(), this);
220 // Only GC uses the OopMapCache during thread stack root scanning
221 // any other uses generate an oopmap but do not save it in the cache.
222 if (Universe::heap()->is_gc_active()) {
223 method_holder()->mask_for(h_this, bci, mask);
224 } else {
225 OopMapCache::compute_one_oop_map(h_this, bci, mask);
226 }
227 return;
228 }
229
230
231 int Method::bci_from(address bcp) const {
232 if (is_native() && bcp == 0) {
233 return 0;
234 }
235 #ifdef ASSERT
236 {
237 ResourceMark rm;
238 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
239 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
240 p2i(bcp), name_and_sig_as_C_string());
241 }
242 #endif
243 return bcp - code_base();
244 }
245
246
247 int Method::validate_bci(int bci) const {
248 return (bci == 0 || bci < code_size()) ? bci : -1;
249 }
250
251 // Return bci if it appears to be a valid bcp
252 // Return -1 otherwise.
253 // Used by profiling code, when invalid data is a possibility.
254 // The caller is responsible for validating the Method* itself.
255 int Method::validate_bci_from_bcp(address bcp) const {
256 // keep bci as -1 if not a valid bci
257 int bci = -1;
258 if (bcp == 0 || bcp == code_base()) {
259 // code_size() may return 0 and we allow 0 here
260 // the method may be native
261 bci = 0;
262 } else if (contains(bcp)) {
263 bci = bcp - code_base();
264 }
265 // Assert that if we have dodged any asserts, bci is negative.
266 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
267 return bci;
268 }
269
270 address Method::bcp_from(int bci) const {
271 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
272 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
273 address bcp = code_base() + bci;
274 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
275 return bcp;
276 }
277
278 address Method::bcp_from(address bcp) const {
279 if (is_native() && bcp == NULL) {
280 return code_base();
281 } else {
282 return bcp;
283 }
284 }
285
286 int Method::size(bool is_native) {
287 // If native, then include pointers for native_function and signature_handler
288 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
289 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
290 return align_metadata_size(header_size() + extra_words);
291 }
292
293
294 Symbol* Method::klass_name() const {
295 return method_holder()->name();
296 }
297
298
299 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
300 log_trace(cds)("Iter(Method): %p", this);
301
302 it->push(&_constMethod);
303 it->push(&_method_data);
304 it->push(&_method_counters);
305 }
306
307 // Attempt to return method oop to original state. Clear any pointers
308 // (to objects outside the shared spaces). We won't be able to predict
309 // where they should point in a new JVM. Further initialize some
310 // entries now in order allow them to be write protected later.
311
312 void Method::remove_unshareable_info() {
313 unlink_method();
314 }
315
316 void Method::set_vtable_index(int index) {
317 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
318 // At runtime initialize_vtable is rerun as part of link_class_impl()
319 // for a shared class loaded by the non-boot loader to obtain the loader
320 // constraints based on the runtime classloaders' context.
321 return; // don't write into the shared class
322 } else {
323 _vtable_index = index;
324 }
325 }
326
327 void Method::set_itable_index(int index) {
328 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
329 // At runtime initialize_itable is rerun as part of link_class_impl()
330 // for a shared class loaded by the non-boot loader to obtain the loader
331 // constraints based on the runtime classloaders' context. The dumptime
332 // itable index should be the same as the runtime index.
333 assert(_vtable_index == itable_index_max - index,
334 "archived itable index is different from runtime index");
335 return; // don’t write into the shared class
336 } else {
337 _vtable_index = itable_index_max - index;
338 }
339 assert(valid_itable_index(), "");
340 }
341
342
343
344 bool Method::was_executed_more_than(int n) {
345 // Invocation counter is reset when the Method* is compiled.
346 // If the method has compiled code we therefore assume it has
347 // be excuted more than n times.
348 if (is_accessor() || is_empty_method() || (code() != NULL)) {
349 // interpreter doesn't bump invocation counter of trivial methods
350 // compiler does not bump invocation counter of compiled methods
351 return true;
352 }
353 else if ((method_counters() != NULL &&
354 method_counters()->invocation_counter()->carry()) ||
355 (method_data() != NULL &&
356 method_data()->invocation_counter()->carry())) {
357 // The carry bit is set when the counter overflows and causes
358 // a compilation to occur. We don't know how many times
359 // the counter has been reset, so we simply assume it has
360 // been executed more than n times.
361 return true;
362 } else {
363 return invocation_count() > n;
364 }
365 }
366
367 void Method::print_invocation_count() {
368 if (is_static()) tty->print("static ");
369 if (is_final()) tty->print("final ");
370 if (is_synchronized()) tty->print("synchronized ");
371 if (is_native()) tty->print("native ");
372 tty->print("%s::", method_holder()->external_name());
373 name()->print_symbol_on(tty);
374 signature()->print_symbol_on(tty);
375
376 if (WizardMode) {
377 // dump the size of the byte codes
378 tty->print(" {%d}", code_size());
379 }
380 tty->cr();
381
382 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count());
383 tty->print_cr (" invocation_counter: %8d ", invocation_count());
384 tty->print_cr (" backedge_counter: %8d ", backedge_count());
385 #ifndef PRODUCT
386 if (CountCompiledCalls) {
387 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count());
388 }
389 #endif
390 }
391
392 // Build a MethodData* object to hold information about this method
393 // collected in the interpreter.
394 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
395 // Do not profile the method if metaspace has hit an OOM previously
396 // allocating profiling data. Callers clear pending exception so don't
397 // add one here.
398 if (ClassLoaderDataGraph::has_metaspace_oom()) {
399 return;
400 }
401
402 // Grab a lock here to prevent multiple
403 // MethodData*s from being created.
404 MutexLocker ml(MethodData_lock, THREAD);
405 if (method->method_data() == NULL) {
406 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
407 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
408 if (HAS_PENDING_EXCEPTION) {
409 CompileBroker::log_metaspace_failure();
410 ClassLoaderDataGraph::set_metaspace_oom(true);
411 return; // return the exception (which is cleared)
412 }
413
414 method->set_method_data(method_data);
415 if (PrintMethodData && (Verbose || WizardMode)) {
416 ResourceMark rm(THREAD);
417 tty->print("build_interpreter_method_data for ");
418 method->print_name(tty);
419 tty->cr();
420 // At the end of the run, the MDO, full of data, will be dumped.
421 }
422 }
423 }
424
425 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
426 // Do not profile the method if metaspace has hit an OOM previously
427 if (ClassLoaderDataGraph::has_metaspace_oom()) {
428 return NULL;
429 }
430
431 methodHandle mh(m);
432 MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
433 if (HAS_PENDING_EXCEPTION) {
434 CompileBroker::log_metaspace_failure();
435 ClassLoaderDataGraph::set_metaspace_oom(true);
436 return NULL; // return the exception (which is cleared)
437 }
438 if (!mh->init_method_counters(counters)) {
439 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
440 }
441
442 if (LogTouchedMethods) {
443 mh->log_touched(CHECK_NULL);
444 }
445
446 return mh->method_counters();
447 }
448
449 bool Method::init_method_counters(MethodCounters* counters) {
450 // Try to install a pointer to MethodCounters, return true on success.
451 return Atomic::replace_if_null(counters, &_method_counters);
452 }
453
454 int Method::extra_stack_words() {
455 // not an inline function, to avoid a header dependency on Interpreter
456 return extra_stack_entries() * Interpreter::stackElementSize;
457 }
458
459
460 void Method::compute_size_of_parameters(Thread *thread) {
461 ArgumentSizeComputer asc(signature());
462 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
463 }
464
465 BasicType Method::result_type() const {
466 ResultTypeFinder rtf(signature());
467 return rtf.type();
468 }
469
470
471 bool Method::is_empty_method() const {
472 return code_size() == 1
473 && *code_base() == Bytecodes::_return;
474 }
475
476
477 bool Method::is_vanilla_constructor() const {
478 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
479 // which only calls the superclass vanilla constructor and possibly does stores of
480 // zero constants to local fields:
481 //
482 // aload_0
483 // invokespecial
484 // indexbyte1
485 // indexbyte2
486 //
487 // followed by an (optional) sequence of:
488 //
489 // aload_0
490 // aconst_null / iconst_0 / fconst_0 / dconst_0
491 // putfield
492 // indexbyte1
493 // indexbyte2
494 //
495 // followed by:
496 //
497 // return
498
499 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
500 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
501 int size = code_size();
502 // Check if size match
503 if (size == 0 || size % 5 != 0) return false;
504 address cb = code_base();
505 int last = size - 1;
506 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
507 // Does not call superclass default constructor
508 return false;
509 }
510 // Check optional sequence
511 for (int i = 4; i < last; i += 5) {
512 if (cb[i] != Bytecodes::_aload_0) return false;
513 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
514 if (cb[i+2] != Bytecodes::_putfield) return false;
515 }
516 return true;
517 }
518
519
520 bool Method::compute_has_loops_flag() {
521 BytecodeStream bcs(this);
522 Bytecodes::Code bc;
523
524 while ((bc = bcs.next()) >= 0) {
525 switch( bc ) {
526 case Bytecodes::_ifeq:
527 case Bytecodes::_ifnull:
528 case Bytecodes::_iflt:
529 case Bytecodes::_ifle:
530 case Bytecodes::_ifne:
531 case Bytecodes::_ifnonnull:
532 case Bytecodes::_ifgt:
533 case Bytecodes::_ifge:
534 case Bytecodes::_if_icmpeq:
535 case Bytecodes::_if_icmpne:
536 case Bytecodes::_if_icmplt:
537 case Bytecodes::_if_icmpgt:
538 case Bytecodes::_if_icmple:
539 case Bytecodes::_if_icmpge:
540 case Bytecodes::_if_acmpeq:
541 case Bytecodes::_if_acmpne:
542 case Bytecodes::_goto:
543 case Bytecodes::_jsr:
544 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
545 break;
546
547 case Bytecodes::_goto_w:
548 case Bytecodes::_jsr_w:
549 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
550 break;
551
552 default:
553 break;
554 }
555 }
556 _access_flags.set_loops_flag_init();
557 return _access_flags.has_loops();
558 }
559
560 bool Method::is_final_method(AccessFlags class_access_flags) const {
561 // or "does_not_require_vtable_entry"
562 // default method or overpass can occur, is not final (reuses vtable entry)
563 // private methods in classes get vtable entries for backward class compatibility.
564 if (is_overpass() || is_default_method()) return false;
565 return is_final() || class_access_flags.is_final();
566 }
567
568 bool Method::is_final_method() const {
569 return is_final_method(method_holder()->access_flags());
570 }
571
572 bool Method::is_default_method() const {
573 if (method_holder() != NULL &&
574 method_holder()->is_interface() &&
575 !is_abstract() && !is_private()) {
576 return true;
577 } else {
578 return false;
579 }
580 }
581
582 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
583 if (is_final_method(class_access_flags)) return true;
584 #ifdef ASSERT
585 ResourceMark rm;
586 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
587 if (class_access_flags.is_interface()) {
588 assert(is_nonv == is_static() || is_nonv == is_private(),
589 "nonvirtual unexpected for non-static, non-private: %s",
590 name_and_sig_as_C_string());
591 }
592 #endif
593 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
594 return vtable_index() == nonvirtual_vtable_index;
595 }
596
597 bool Method::can_be_statically_bound() const {
598 return can_be_statically_bound(method_holder()->access_flags());
599 }
600
601 bool Method::is_accessor() const {
602 return is_getter() || is_setter();
603 }
604
605 bool Method::is_getter() const {
606 if (code_size() != 5) return false;
607 if (size_of_parameters() != 1) return false;
608 if (java_code_at(0) != Bytecodes::_aload_0) return false;
609 if (java_code_at(1) != Bytecodes::_getfield) return false;
610 switch (java_code_at(4)) {
611 case Bytecodes::_ireturn:
612 case Bytecodes::_lreturn:
613 case Bytecodes::_freturn:
614 case Bytecodes::_dreturn:
615 case Bytecodes::_areturn:
616 break;
617 default:
618 return false;
619 }
620 return true;
621 }
622
623 bool Method::is_setter() const {
624 if (code_size() != 6) return false;
625 if (java_code_at(0) != Bytecodes::_aload_0) return false;
626 switch (java_code_at(1)) {
627 case Bytecodes::_iload_1:
628 case Bytecodes::_aload_1:
629 case Bytecodes::_fload_1:
630 if (size_of_parameters() != 2) return false;
631 break;
632 case Bytecodes::_dload_1:
633 case Bytecodes::_lload_1:
634 if (size_of_parameters() != 3) return false;
635 break;
636 default:
637 return false;
638 }
639 if (java_code_at(2) != Bytecodes::_putfield) return false;
640 if (java_code_at(5) != Bytecodes::_return) return false;
641 return true;
642 }
643
644 bool Method::is_constant_getter() const {
645 int last_index = code_size() - 1;
646 // Check if the first 1-3 bytecodes are a constant push
647 // and the last bytecode is a return.
648 return (2 <= code_size() && code_size() <= 4 &&
649 Bytecodes::is_const(java_code_at(0)) &&
650 Bytecodes::length_for(java_code_at(0)) == last_index &&
651 Bytecodes::is_return(java_code_at(last_index)));
652 }
653
654 bool Method::is_initializer() const {
655 return is_object_initializer() || is_static_initializer();
656 }
657
658 bool Method::has_valid_initializer_flags() const {
659 return (is_static() ||
660 method_holder()->major_version() < 51);
661 }
662
663 bool Method::is_static_initializer() const {
664 // For classfiles version 51 or greater, ensure that the clinit method is
665 // static. Non-static methods with the name "<clinit>" are not static
666 // initializers. (older classfiles exempted for backward compatibility)
667 return name() == vmSymbols::class_initializer_name() &&
668 has_valid_initializer_flags();
669 }
670
671 bool Method::is_object_initializer() const {
672 return name() == vmSymbols::object_initializer_name();
673 }
674
675 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
676 int length = method->checked_exceptions_length();
677 if (length == 0) { // common case
678 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
679 } else {
680 methodHandle h_this(THREAD, method);
681 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
682 objArrayHandle mirrors (THREAD, m_oop);
683 for (int i = 0; i < length; i++) {
684 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
685 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
686 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
687 mirrors->obj_at_put(i, k->java_mirror());
688 }
689 return mirrors;
690 }
691 };
692
693
694 int Method::line_number_from_bci(int bci) const {
695 int best_bci = 0;
696 int best_line = -1;
697 if (bci == SynchronizationEntryBCI) bci = 0;
698 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
699 // The line numbers are a short array of 2-tuples [start_pc, line_number].
700 // Not necessarily sorted and not necessarily one-to-one.
701 CompressedLineNumberReadStream stream(compressed_linenumber_table());
702 while (stream.read_pair()) {
703 if (stream.bci() == bci) {
704 // perfect match
705 return stream.line();
706 } else {
707 // update best_bci/line
708 if (stream.bci() < bci && stream.bci() >= best_bci) {
709 best_bci = stream.bci();
710 best_line = stream.line();
711 }
712 }
713 }
714 }
715 return best_line;
716 }
717
718
719 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
720 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
721 Thread *thread = Thread::current();
722 Symbol* klass_name = constants()->klass_name_at(klass_index);
723 Handle loader(thread, method_holder()->class_loader());
724 Handle prot (thread, method_holder()->protection_domain());
725 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
726 } else {
727 return true;
728 }
729 }
730
731
732 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
733 int klass_index = constants()->klass_ref_index_at(refinfo_index);
734 if (must_be_resolved) {
735 // Make sure klass is resolved in constantpool.
736 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
737 }
738 return is_klass_loaded_by_klass_index(klass_index);
739 }
740
741
742 void Method::set_native_function(address function, bool post_event_flag) {
743 assert(function != NULL, "use clear_native_function to unregister natives");
744 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
745 address* native_function = native_function_addr();
746
747 // We can see racers trying to place the same native function into place. Once
748 // is plenty.
749 address current = *native_function;
750 if (current == function) return;
751 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
752 function != NULL) {
753 // native_method_throw_unsatisfied_link_error_entry() should only
754 // be passed when post_event_flag is false.
755 assert(function !=
756 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
757 "post_event_flag mis-match");
758
759 // post the bind event, and possible change the bind function
760 JvmtiExport::post_native_method_bind(this, &function);
761 }
762 *native_function = function;
763 // This function can be called more than once. We must make sure that we always
764 // use the latest registered method -> check if a stub already has been generated.
765 // If so, we have to make it not_entrant.
766 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
767 if (nm != NULL) {
768 nm->make_not_entrant();
769 }
770 }
771
772
773 bool Method::has_native_function() const {
774 if (is_method_handle_intrinsic())
775 return false; // special-cased in SharedRuntime::generate_native_wrapper
776 address func = native_function();
777 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
778 }
779
780
781 void Method::clear_native_function() {
782 // Note: is_method_handle_intrinsic() is allowed here.
783 set_native_function(
784 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
785 !native_bind_event_is_interesting);
786 clear_code();
787 }
788
789 address Method::critical_native_function() {
790 methodHandle mh(this);
791 return NativeLookup::lookup_critical_entry(mh);
792 }
793
794
795 void Method::set_signature_handler(address handler) {
796 address* signature_handler = signature_handler_addr();
797 *signature_handler = handler;
798 }
799
800
801 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
802 if (PrintCompilation && report) {
803 ttyLocker ttyl;
804 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
805 if (comp_level == CompLevel_all) {
806 tty->print("all levels ");
807 } else {
808 tty->print("levels ");
809 for (int i = (int)CompLevel_none; i <= comp_level; i++) {
810 tty->print("%d ", i);
811 }
812 }
813 this->print_short_name(tty);
814 int size = this->code_size();
815 if (size > 0) {
816 tty->print(" (%d bytes)", size);
817 }
818 if (reason != NULL) {
819 tty->print(" %s", reason);
820 }
821 tty->cr();
822 }
823 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
824 ttyLocker ttyl;
825 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
826 os::current_thread_id(), is_osr, comp_level);
827 if (reason != NULL) {
828 xtty->print(" reason=\'%s\'", reason);
829 }
830 xtty->method(this);
831 xtty->stamp();
832 xtty->end_elem();
833 }
834 }
835
836 bool Method::is_always_compilable() const {
837 // Generated adapters must be compiled
838 if (is_method_handle_intrinsic() && is_synthetic()) {
839 assert(!is_not_c1_compilable(), "sanity check");
840 assert(!is_not_c2_compilable(), "sanity check");
841 return true;
842 }
843
844 return false;
845 }
846
847 bool Method::is_not_compilable(int comp_level) const {
848 if (number_of_breakpoints() > 0)
849 return true;
850 if (is_always_compilable())
851 return false;
852 if (comp_level == CompLevel_any)
853 return is_not_c1_compilable() || is_not_c2_compilable();
854 if (is_c1_compile(comp_level))
855 return is_not_c1_compilable();
856 if (is_c2_compile(comp_level))
857 return is_not_c2_compilable();
858 return false;
859 }
860
861 // call this when compiler finds that this method is not compilable
862 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
863 if (is_always_compilable()) {
864 // Don't mark a method which should be always compilable
865 return;
866 }
867 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
868 if (comp_level == CompLevel_all) {
869 set_not_c1_compilable();
870 set_not_c2_compilable();
871 } else {
872 if (is_c1_compile(comp_level))
873 set_not_c1_compilable();
874 if (is_c2_compile(comp_level))
875 set_not_c2_compilable();
876 }
877 CompilationPolicy::policy()->disable_compilation(this);
878 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
879 }
880
881 bool Method::is_not_osr_compilable(int comp_level) const {
882 if (is_not_compilable(comp_level))
883 return true;
884 if (comp_level == CompLevel_any)
885 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
886 if (is_c1_compile(comp_level))
887 return is_not_c1_osr_compilable();
888 if (is_c2_compile(comp_level))
889 return is_not_c2_osr_compilable();
890 return false;
891 }
892
893 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
894 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
895 if (comp_level == CompLevel_all) {
896 set_not_c1_osr_compilable();
897 set_not_c2_osr_compilable();
898 } else {
899 if (is_c1_compile(comp_level))
900 set_not_c1_osr_compilable();
901 if (is_c2_compile(comp_level))
902 set_not_c2_osr_compilable();
903 }
904 CompilationPolicy::policy()->disable_compilation(this);
905 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
906 }
907
908 // Revert to using the interpreter and clear out the nmethod
909 void Method::clear_code(bool acquire_lock /* = true */) {
910 MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
911 // this may be NULL if c2i adapters have not been made yet
912 // Only should happen at allocate time.
913 if (adapter() == NULL) {
914 _from_compiled_entry = NULL;
915 } else {
916 _from_compiled_entry = adapter()->get_c2i_entry();
917 }
918 OrderAccess::storestore();
919 _from_interpreted_entry = _i2i_entry;
920 OrderAccess::storestore();
921 _code = NULL;
922 }
923
924 #if INCLUDE_CDS
925 // Called by class data sharing to remove any entry points (which are not shared)
926 void Method::unlink_method() {
927 _code = NULL;
928
929 assert(DumpSharedSpaces, "dump time only");
930 // Set the values to what they should be at run time. Note that
931 // this Method can no longer be executed during dump time.
932 _i2i_entry = Interpreter::entry_for_cds_method(this);
933 _from_interpreted_entry = _i2i_entry;
934
935 if (is_native()) {
936 *native_function_addr() = NULL;
937 set_signature_handler(NULL);
938 }
939 NOT_PRODUCT(set_compiled_invocation_count(0);)
940
941 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
942 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
943 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
944 assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
945
946 set_method_data(NULL);
947 clear_method_counters();
948 }
949 #endif
950
951 /****************************************************************************
952 // The following illustrates how the entries work for CDS shared Methods:
953 //
954 // Our goal is to delay writing into a shared Method until it's compiled.
955 // Hence, we want to determine the initial values for _i2i_entry,
956 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
957 //
958 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
959 // They also have similar signatures so that they will share the same
960 // AdapterHandlerEntry.
961 //
962 // _adapter_trampoline points to a fixed location in the RW section of
963 // the CDS archive. This location initially contains a NULL pointer. When the
964 // first of method A or B is linked, an AdapterHandlerEntry is allocated
965 // dynamically, and its c2i/i2c entries are generated.
966 //
967 // _i2i_entry and _from_interpreted_entry initially points to the same
968 // (fixed) location in the CODE section of the CDS archive. This contains
969 // an unconditional branch to the actual entry for "zero_locals", which is
970 // generated at run time and may be on an arbitrary address. Thus, the
971 // unconditional branch is also generated at run time to jump to the correct
972 // address.
973 //
974 // Similarly, _from_compiled_entry points to a fixed address in the CODE
975 // section. This address has enough space for an unconditional branch
976 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
977 // initialized, and the address for the actual c2i_entry is known, we emit a
978 // branch instruction here to branch to the actual c2i_entry.
979 //
980 // The effect of the extra branch on the i2i and c2i entries is negligible.
981 //
982 // The reason for putting _adapter_trampoline in RO is many shared Methods
983 // share the same AdapterHandlerEntry, so we can save space in the RW section
984 // by having the extra indirection.
985
986
987 [Method A: RW]
988 _constMethod ----> [ConstMethod: RO]
989 _adapter_trampoline -----------+
990 |
991 _i2i_entry (same value as method B) |
992 _from_interpreted_entry (same value as method B) |
993 _from_compiled_entry (same value as method B) |
994 |
995 |
996 [Method B: RW] +--------+
997 _constMethod ----> [ConstMethod: RO] |
998 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
999 |
1000 +-------------------------------+
1001 |
1002 +----> [AdapterHandlerEntry] (allocated at run time)
1003 _fingerprint
1004 _c2i_entry ---------------------------------+->[c2i entry..]
1005 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1006 _from_interpreted_entry | _c2i_unverified_entry | |
1007 | | | |
1008 | | (_cds_entry_table: CODE) | |
1009 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1010 | | (allocated at run time) | |
1011 | | ... [asm code ...] | |
1012 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1013 | | |
1014 | | |
1015 +-[compiled]-------------------------------------------------------------------+ |
1016 |
1017 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1018 [jmp c2i_entry] ------------------------------------------------------+
1019
1020 ***/
1021
1022 // Called when the method_holder is getting linked. Setup entrypoints so the method
1023 // is ready to be called from interpreter, compiler, and vtables.
1024 void Method::link_method(const methodHandle& h_method, TRAPS) {
1025 // If the code cache is full, we may reenter this function for the
1026 // leftover methods that weren't linked.
1027 if (is_shared()) {
1028 address entry = Interpreter::entry_for_cds_method(h_method);
1029 assert(entry != NULL && entry == _i2i_entry,
1030 "should be correctly set during dump time");
1031 if (adapter() != NULL) {
1032 return;
1033 }
1034 assert(entry == _from_interpreted_entry,
1035 "should be correctly set during dump time");
1036 } else if (_i2i_entry != NULL) {
1037 return;
1038 }
1039 assert( _code == NULL, "nothing compiled yet" );
1040
1041 // Setup interpreter entrypoint
1042 assert(this == h_method(), "wrong h_method()" );
1043
1044 if (!is_shared()) {
1045 assert(adapter() == NULL, "init'd to NULL");
1046 address entry = Interpreter::entry_for_method(h_method);
1047 assert(entry != NULL, "interpreter entry must be non-null");
1048 // Sets both _i2i_entry and _from_interpreted_entry
1049 set_interpreter_entry(entry);
1050 }
1051
1052 // Don't overwrite already registered native entries.
1053 if (is_native() && !has_native_function()) {
1054 set_native_function(
1055 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1056 !native_bind_event_is_interesting);
1057 }
1058
1059 // Setup compiler entrypoint. This is made eagerly, so we do not need
1060 // special handling of vtables. An alternative is to make adapters more
1061 // lazily by calling make_adapter() from from_compiled_entry() for the
1062 // normal calls. For vtable calls life gets more complicated. When a
1063 // call-site goes mega-morphic we need adapters in all methods which can be
1064 // called from the vtable. We need adapters on such methods that get loaded
1065 // later. Ditto for mega-morphic itable calls. If this proves to be a
1066 // problem we'll make these lazily later.
1067 (void) make_adapters(h_method, CHECK);
1068
1069 // ONLY USE the h_method now as make_adapter may have blocked
1070
1071 }
1072
1073 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1074 // Adapters for compiled code are made eagerly here. They are fairly
1075 // small (generally < 100 bytes) and quick to make (and cached and shared)
1076 // so making them eagerly shouldn't be too expensive.
1077 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1078 if (adapter == NULL ) {
1079 if (!is_init_completed()) {
1080 // Don't throw exceptions during VM initialization because java.lang.* classes
1081 // might not have been initialized, causing problems when constructing the
1082 // Java exception object.
1083 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1084 } else {
1085 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1086 }
1087 }
1088
1089 if (mh->is_shared()) {
1090 assert(mh->adapter() == adapter, "must be");
1091 assert(mh->_from_compiled_entry != NULL, "must be");
1092 } else {
1093 mh->set_adapter_entry(adapter);
1094 mh->_from_compiled_entry = adapter->get_c2i_entry();
1095 }
1096 return adapter->get_c2i_entry();
1097 }
1098
1099 void Method::restore_unshareable_info(TRAPS) {
1100 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1101
1102 // Since restore_unshareable_info can be called more than once for a method, don't
1103 // redo any work.
1104 if (adapter() == NULL) {
1105 methodHandle mh(THREAD, this);
1106 link_method(mh, CHECK);
1107 }
1108 }
1109
1110 address Method::from_compiled_entry_no_trampoline() const {
1111 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1112 if (code) {
1113 return code->verified_entry_point();
1114 } else {
1115 return adapter()->get_c2i_entry();
1116 }
1117 }
1118
1119 // The verified_code_entry() must be called when a invoke is resolved
1120 // on this method.
1121
1122 // It returns the compiled code entry point, after asserting not null.
1123 // This function is called after potential safepoints so that nmethod
1124 // or adapter that it points to is still live and valid.
1125 // This function must not hit a safepoint!
1126 address Method::verified_code_entry() {
1127 debug_only(NoSafepointVerifier nsv;)
1128 assert(_from_compiled_entry != NULL, "must be set");
1129 return _from_compiled_entry;
1130 }
1131
1132 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1133 // (could be racing a deopt).
1134 // Not inline to avoid circular ref.
1135 bool Method::check_code() const {
1136 // cached in a register or local. There's a race on the value of the field.
1137 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1138 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1139 }
1140
1141 // Install compiled code. Instantly it can execute.
1142 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1143 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1144 assert( code, "use clear_code to remove code" );
1145 assert( mh->check_code(), "" );
1146
1147 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1148
1149 // These writes must happen in this order, because the interpreter will
1150 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1151 // which jumps to _from_compiled_entry.
1152 mh->_code = code; // Assign before allowing compiled code to exec
1153
1154 int comp_level = code->comp_level();
1155 // In theory there could be a race here. In practice it is unlikely
1156 // and not worth worrying about.
1157 if (comp_level > mh->highest_comp_level()) {
1158 mh->set_highest_comp_level(comp_level);
1159 }
1160
1161 OrderAccess::storestore();
1162 mh->_from_compiled_entry = code->verified_entry_point();
1163 OrderAccess::storestore();
1164 // Instantly compiled code can execute.
1165 if (!mh->is_method_handle_intrinsic())
1166 mh->_from_interpreted_entry = mh->get_i2c_entry();
1167 }
1168
1169
1170 bool Method::is_overridden_in(Klass* k) const {
1171 InstanceKlass* ik = InstanceKlass::cast(k);
1172
1173 if (ik->is_interface()) return false;
1174
1175 // If method is an interface, we skip it - except if it
1176 // is a miranda method
1177 if (method_holder()->is_interface()) {
1178 // Check that method is not a miranda method
1179 if (ik->lookup_method(name(), signature()) == NULL) {
1180 // No implementation exist - so miranda method
1181 return false;
1182 }
1183 return true;
1184 }
1185
1186 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1187 if (!has_vtable_index()) {
1188 return false;
1189 } else {
1190 Method* vt_m = ik->method_at_vtable(vtable_index());
1191 return vt_m != this;
1192 }
1193 }
1194
1195
1196 // give advice about whether this Method* should be cached or not
1197 bool Method::should_not_be_cached() const {
1198 if (is_old()) {
1199 // This method has been redefined. It is either EMCP or obsolete
1200 // and we don't want to cache it because that would pin the method
1201 // down and prevent it from being collectible if and when it
1202 // finishes executing.
1203 return true;
1204 }
1205
1206 // caching this method should be just fine
1207 return false;
1208 }
1209
1210
1211 /**
1212 * Returns true if this is one of the specially treated methods for
1213 * security related stack walks (like Reflection.getCallerClass).
1214 */
1215 bool Method::is_ignored_by_security_stack_walk() const {
1216 if (intrinsic_id() == vmIntrinsics::_invoke) {
1217 // This is Method.invoke() -- ignore it
1218 return true;
1219 }
1220 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1221 // This is an auxilary frame -- ignore it
1222 return true;
1223 }
1224 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1225 // This is an internal adapter frame for method handles -- ignore it
1226 return true;
1227 }
1228 return false;
1229 }
1230
1231
1232 // Constant pool structure for invoke methods:
1233 enum {
1234 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1235 _imcp_invoke_signature, // utf8: (variable Symbol*)
1236 _imcp_limit
1237 };
1238
1239 // Test if this method is an MH adapter frame generated by Java code.
1240 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1241 bool Method::is_compiled_lambda_form() const {
1242 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1243 }
1244
1245 // Test if this method is an internal MH primitive method.
1246 bool Method::is_method_handle_intrinsic() const {
1247 vmIntrinsics::ID iid = intrinsic_id();
1248 return (MethodHandles::is_signature_polymorphic(iid) &&
1249 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1250 }
1251
1252 bool Method::has_member_arg() const {
1253 vmIntrinsics::ID iid = intrinsic_id();
1254 return (MethodHandles::is_signature_polymorphic(iid) &&
1255 MethodHandles::has_member_arg(iid));
1256 }
1257
1258 // Make an instance of a signature-polymorphic internal MH primitive.
1259 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1260 Symbol* signature,
1261 TRAPS) {
1262 ResourceMark rm;
1263 methodHandle empty;
1264
1265 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1266 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1267 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1268 if (TraceMethodHandles) {
1269 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1270 }
1271
1272 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1273 name->increment_refcount();
1274 signature->increment_refcount();
1275
1276 int cp_length = _imcp_limit;
1277 ClassLoaderData* loader_data = holder->class_loader_data();
1278 constantPoolHandle cp;
1279 {
1280 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1281 cp = constantPoolHandle(THREAD, cp_oop);
1282 }
1283 cp->set_pool_holder(holder);
1284 cp->symbol_at_put(_imcp_invoke_name, name);
1285 cp->symbol_at_put(_imcp_invoke_signature, signature);
1286 cp->set_has_preresolution();
1287
1288 // decide on access bits: public or not?
1289 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1290 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1291 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1292 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1293
1294 methodHandle m;
1295 {
1296 InlineTableSizes sizes;
1297 Method* m_oop = Method::allocate(loader_data, 0,
1298 accessFlags_from(flags_bits), &sizes,
1299 ConstMethod::NORMAL, CHECK_(empty));
1300 m = methodHandle(THREAD, m_oop);
1301 }
1302 m->set_constants(cp());
1303 m->set_name_index(_imcp_invoke_name);
1304 m->set_signature_index(_imcp_invoke_signature);
1305 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1306 assert(m->signature() == signature, "");
1307 ResultTypeFinder rtf(signature);
1308 m->constMethod()->set_result_type(rtf.type());
1309 m->compute_size_of_parameters(THREAD);
1310 m->init_intrinsic_id();
1311 assert(m->is_method_handle_intrinsic(), "");
1312 #ifdef ASSERT
1313 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1314 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1315 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1316 #endif //ASSERT
1317
1318 // Finally, set up its entry points.
1319 assert(m->can_be_statically_bound(), "");
1320 m->set_vtable_index(Method::nonvirtual_vtable_index);
1321 m->link_method(m, CHECK_(empty));
1322
1323 if (TraceMethodHandles && (Verbose || WizardMode)) {
1324 ttyLocker ttyl;
1325 m->print_on(tty);
1326 }
1327
1328 return m;
1329 }
1330
1331 Klass* Method::check_non_bcp_klass(Klass* klass) {
1332 if (klass != NULL && klass->class_loader() != NULL) {
1333 if (klass->is_objArray_klass())
1334 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1335 return klass;
1336 }
1337 return NULL;
1338 }
1339
1340
1341 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1342 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1343 // Code below does not work for native methods - they should never get rewritten anyway
1344 assert(!m->is_native(), "cannot rewrite native methods");
1345 // Allocate new Method*
1346 AccessFlags flags = m->access_flags();
1347
1348 ConstMethod* cm = m->constMethod();
1349 int checked_exceptions_len = cm->checked_exceptions_length();
1350 int localvariable_len = cm->localvariable_table_length();
1351 int exception_table_len = cm->exception_table_length();
1352 int method_parameters_len = cm->method_parameters_length();
1353 int method_annotations_len = cm->method_annotations_length();
1354 int parameter_annotations_len = cm->parameter_annotations_length();
1355 int type_annotations_len = cm->type_annotations_length();
1356 int default_annotations_len = cm->default_annotations_length();
1357
1358 InlineTableSizes sizes(
1359 localvariable_len,
1360 new_compressed_linenumber_size,
1361 exception_table_len,
1362 checked_exceptions_len,
1363 method_parameters_len,
1364 cm->generic_signature_index(),
1365 method_annotations_len,
1366 parameter_annotations_len,
1367 type_annotations_len,
1368 default_annotations_len,
1369 0);
1370
1371 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1372 Method* newm_oop = Method::allocate(loader_data,
1373 new_code_length,
1374 flags,
1375 &sizes,
1376 m->method_type(),
1377 CHECK_(methodHandle()));
1378 methodHandle newm (THREAD, newm_oop);
1379
1380 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1381 ConstMethod* newcm = newm->constMethod();
1382 int new_const_method_size = newm->constMethod()->size();
1383
1384 // This works because the source and target are both Methods. Some compilers
1385 // (e.g., clang) complain that the target vtable pointer will be stomped,
1386 // so cast away newm()'s and m()'s Methodness.
1387 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1388
1389 // Create shallow copy of ConstMethod.
1390 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1391
1392 // Reset correct method/const method, method size, and parameter info
1393 newm->set_constMethod(newcm);
1394 newm->constMethod()->set_code_size(new_code_length);
1395 newm->constMethod()->set_constMethod_size(new_const_method_size);
1396 assert(newm->code_size() == new_code_length, "check");
1397 assert(newm->method_parameters_length() == method_parameters_len, "check");
1398 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1399 assert(newm->exception_table_length() == exception_table_len, "check");
1400 assert(newm->localvariable_table_length() == localvariable_len, "check");
1401 // Copy new byte codes
1402 memcpy(newm->code_base(), new_code, new_code_length);
1403 // Copy line number table
1404 if (new_compressed_linenumber_size > 0) {
1405 memcpy(newm->compressed_linenumber_table(),
1406 new_compressed_linenumber_table,
1407 new_compressed_linenumber_size);
1408 }
1409 // Copy method_parameters
1410 if (method_parameters_len > 0) {
1411 memcpy(newm->method_parameters_start(),
1412 m->method_parameters_start(),
1413 method_parameters_len * sizeof(MethodParametersElement));
1414 }
1415 // Copy checked_exceptions
1416 if (checked_exceptions_len > 0) {
1417 memcpy(newm->checked_exceptions_start(),
1418 m->checked_exceptions_start(),
1419 checked_exceptions_len * sizeof(CheckedExceptionElement));
1420 }
1421 // Copy exception table
1422 if (exception_table_len > 0) {
1423 memcpy(newm->exception_table_start(),
1424 m->exception_table_start(),
1425 exception_table_len * sizeof(ExceptionTableElement));
1426 }
1427 // Copy local variable number table
1428 if (localvariable_len > 0) {
1429 memcpy(newm->localvariable_table_start(),
1430 m->localvariable_table_start(),
1431 localvariable_len * sizeof(LocalVariableTableElement));
1432 }
1433 // Copy stackmap table
1434 if (m->has_stackmap_table()) {
1435 int code_attribute_length = m->stackmap_data()->length();
1436 Array<u1>* stackmap_data =
1437 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1438 memcpy((void*)stackmap_data->adr_at(0),
1439 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1440 newm->set_stackmap_data(stackmap_data);
1441 }
1442
1443 // copy annotations over to new method
1444 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1445 return newm;
1446 }
1447
1448 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1449 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1450 // because we are not loading from core libraries
1451 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1452 // which does not use the class default class loader so we check for its loader here
1453 const InstanceKlass* ik = InstanceKlass::cast(holder);
1454 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1455 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1456 }
1457
1458 // see if the klass name is well-known:
1459 Symbol* klass_name = ik->name();
1460 return vmSymbols::find_sid(klass_name);
1461 }
1462
1463 void Method::init_intrinsic_id() {
1464 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1465 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1466 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1467 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1468
1469 // the klass name is well-known:
1470 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1471 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1472
1473 // ditto for method and signature:
1474 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1475 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1476 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1477 && name_id == vmSymbols::NO_SID) {
1478 return;
1479 }
1480 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1481 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1482 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1483 && sig_id == vmSymbols::NO_SID) {
1484 return;
1485 }
1486 jshort flags = access_flags().as_short();
1487
1488 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1489 if (id != vmIntrinsics::_none) {
1490 set_intrinsic_id(id);
1491 if (id == vmIntrinsics::_Class_cast) {
1492 // Even if the intrinsic is rejected, we want to inline this simple method.
1493 set_force_inline(true);
1494 }
1495 return;
1496 }
1497
1498 // A few slightly irregular cases:
1499 switch (klass_id) {
1500 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1501 // Second chance: check in regular Math.
1502 switch (name_id) {
1503 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1504 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1505 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1506 // pretend it is the corresponding method in the non-strict class:
1507 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1508 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1509 break;
1510 default:
1511 break;
1512 }
1513 break;
1514
1515 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1516 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1517 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1518 if (!is_native()) break;
1519 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1520 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1521 id = vmIntrinsics::_none;
1522 break;
1523
1524 default:
1525 break;
1526 }
1527
1528 if (id != vmIntrinsics::_none) {
1529 // Set up its iid. It is an alias method.
1530 set_intrinsic_id(id);
1531 return;
1532 }
1533 }
1534
1535 // These two methods are static since a GC may move the Method
1536 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1537 if (!THREAD->can_call_java()) {
1538 // There is nothing useful this routine can do from within the Compile thread.
1539 // Hopefully, the signature contains only well-known classes.
1540 // We could scan for this and return true/false, but the caller won't care.
1541 return false;
1542 }
1543 bool sig_is_loaded = true;
1544 Handle class_loader(THREAD, m->method_holder()->class_loader());
1545 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1546 ResourceMark rm(THREAD);
1547 Symbol* signature = m->signature();
1548 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1549 if (ss.is_object()) {
1550 Symbol* sym = ss.as_symbol(CHECK_(false));
1551 Symbol* name = sym;
1552 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1553 protection_domain, THREAD);
1554 // We are loading classes eagerly. If a ClassNotFoundException or
1555 // a LinkageError was generated, be sure to ignore it.
1556 if (HAS_PENDING_EXCEPTION) {
1557 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1558 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1559 CLEAR_PENDING_EXCEPTION;
1560 } else {
1561 return false;
1562 }
1563 }
1564 if( klass == NULL) { sig_is_loaded = false; }
1565 }
1566 }
1567 return sig_is_loaded;
1568 }
1569
1570 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1571 Handle class_loader(THREAD, m->method_holder()->class_loader());
1572 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1573 ResourceMark rm(THREAD);
1574 Symbol* signature = m->signature();
1575 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1576 if (ss.type() == T_OBJECT) {
1577 Symbol* name = ss.as_symbol_or_null();
1578 if (name == NULL) return true;
1579 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1580 if (klass == NULL) return true;
1581 }
1582 }
1583 return false;
1584 }
1585
1586 // Exposed so field engineers can debug VM
1587 void Method::print_short_name(outputStream* st) {
1588 ResourceMark rm;
1589 #ifdef PRODUCT
1590 st->print(" %s::", method_holder()->external_name());
1591 #else
1592 st->print(" %s::", method_holder()->internal_name());
1593 #endif
1594 name()->print_symbol_on(st);
1595 if (WizardMode) signature()->print_symbol_on(st);
1596 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1597 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1598 }
1599
1600 // Comparer for sorting an object array containing
1601 // Method*s.
1602 static int method_comparator(Method* a, Method* b) {
1603 return a->name()->fast_compare(b->name());
1604 }
1605
1606 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1607 // default_methods also uses this without the ordering for fast find_method
1608 void Method::sort_methods(Array<Method*>* methods, bool set_idnums) {
1609 int length = methods->length();
1610 if (length > 1) {
1611 {
1612 NoSafepointVerifier nsv;
1613 QuickSort::sort(methods->data(), length, method_comparator, /*idempotent=*/false);
1614 }
1615 // Reset method ordering
1616 if (set_idnums) {
1617 for (int i = 0; i < length; i++) {
1618 Method* m = methods->at(i);
1619 m->set_method_idnum(i);
1620 m->set_orig_method_idnum(i);
1621 }
1622 }
1623 }
1624 }
1625
1626 //-----------------------------------------------------------------------------------
1627 // Non-product code unless JVM/TI needs it
1628
1629 #if !defined(PRODUCT) || INCLUDE_JVMTI
1630 class SignatureTypePrinter : public SignatureTypeNames {
1631 private:
1632 outputStream* _st;
1633 bool _use_separator;
1634
1635 void type_name(const char* name) {
1636 if (_use_separator) _st->print(", ");
1637 _st->print("%s", name);
1638 _use_separator = true;
1639 }
1640
1641 public:
1642 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1643 _st = st;
1644 _use_separator = false;
1645 }
1646
1647 void print_parameters() { _use_separator = false; iterate_parameters(); }
1648 void print_returntype() { _use_separator = false; iterate_returntype(); }
1649 };
1650
1651
1652 void Method::print_name(outputStream* st) {
1653 Thread *thread = Thread::current();
1654 ResourceMark rm(thread);
1655 st->print("%s ", is_static() ? "static" : "virtual");
1656 if (WizardMode) {
1657 st->print("%s.", method_holder()->internal_name());
1658 name()->print_symbol_on(st);
1659 signature()->print_symbol_on(st);
1660 } else {
1661 SignatureTypePrinter sig(signature(), st);
1662 sig.print_returntype();
1663 st->print(" %s.", method_holder()->internal_name());
1664 name()->print_symbol_on(st);
1665 st->print("(");
1666 sig.print_parameters();
1667 st->print(")");
1668 }
1669 }
1670 #endif // !PRODUCT || INCLUDE_JVMTI
1671
1672
1673 void Method::print_codes_on(outputStream* st) const {
1674 print_codes_on(0, code_size(), st);
1675 }
1676
1677 void Method::print_codes_on(int from, int to, outputStream* st) const {
1678 Thread *thread = Thread::current();
1679 ResourceMark rm(thread);
1680 methodHandle mh (thread, (Method*)this);
1681 BytecodeStream s(mh);
1682 s.set_interval(from, to);
1683 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1684 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1685 }
1686
1687
1688 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1689 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1690 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1691 // as end-of-stream terminator.
1692
1693 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1694 // bci and line number does not compress into single byte.
1695 // Write out escape character and use regular compression for bci and line number.
1696 write_byte((jubyte)0xFF);
1697 write_signed_int(bci_delta);
1698 write_signed_int(line_delta);
1699 }
1700
1701 // See comment in method.hpp which explains why this exists.
1702 #if defined(_M_AMD64) && _MSC_VER >= 1400
1703 #pragma optimize("", off)
1704 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1705 write_pair_inline(bci, line);
1706 }
1707 #pragma optimize("", on)
1708 #endif
1709
1710 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1711 _bci = 0;
1712 _line = 0;
1713 };
1714
1715
1716 bool CompressedLineNumberReadStream::read_pair() {
1717 jubyte next = read_byte();
1718 // Check for terminator
1719 if (next == 0) return false;
1720 if (next == 0xFF) {
1721 // Escape character, regular compression used
1722 _bci += read_signed_int();
1723 _line += read_signed_int();
1724 } else {
1725 // Single byte compression used
1726 _bci += next >> 3;
1727 _line += next & 0x7;
1728 }
1729 return true;
1730 }
1731
1732 #if INCLUDE_JVMTI
1733
1734 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1735 BreakpointInfo* bp = method_holder()->breakpoints();
1736 for (; bp != NULL; bp = bp->next()) {
1737 if (bp->match(this, bci)) {
1738 return bp->orig_bytecode();
1739 }
1740 }
1741 {
1742 ResourceMark rm;
1743 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1744 }
1745 return Bytecodes::_shouldnotreachhere;
1746 }
1747
1748 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1749 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1750 BreakpointInfo* bp = method_holder()->breakpoints();
1751 for (; bp != NULL; bp = bp->next()) {
1752 if (bp->match(this, bci)) {
1753 bp->set_orig_bytecode(code);
1754 // and continue, in case there is more than one
1755 }
1756 }
1757 }
1758
1759 void Method::set_breakpoint(int bci) {
1760 InstanceKlass* ik = method_holder();
1761 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1762 bp->set_next(ik->breakpoints());
1763 ik->set_breakpoints(bp);
1764 // do this last:
1765 bp->set(this);
1766 }
1767
1768 static void clear_matches(Method* m, int bci) {
1769 InstanceKlass* ik = m->method_holder();
1770 BreakpointInfo* prev_bp = NULL;
1771 BreakpointInfo* next_bp;
1772 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1773 next_bp = bp->next();
1774 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1775 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1776 // do this first:
1777 bp->clear(m);
1778 // unhook it
1779 if (prev_bp != NULL)
1780 prev_bp->set_next(next_bp);
1781 else
1782 ik->set_breakpoints(next_bp);
1783 delete bp;
1784 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1785 // at same location. So we have multiple matching (method_index and bci)
1786 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1787 // breakpoint for clear_breakpoint request and keep all other method versions
1788 // BreakpointInfo for future clear_breakpoint request.
1789 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1790 // which is being called when class is unloaded. We delete all the Breakpoint
1791 // information for all versions of method. We may not correctly restore the original
1792 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1793 // so these methods won't be used anymore.
1794 if (bci >= 0) {
1795 break;
1796 }
1797 } else {
1798 // This one is a keeper.
1799 prev_bp = bp;
1800 }
1801 }
1802 }
1803
1804 void Method::clear_breakpoint(int bci) {
1805 assert(bci >= 0, "");
1806 clear_matches(this, bci);
1807 }
1808
1809 void Method::clear_all_breakpoints() {
1810 clear_matches(this, -1);
1811 }
1812
1813 #endif // INCLUDE_JVMTI
1814
1815 int Method::invocation_count() {
1816 MethodCounters *mcs = method_counters();
1817 if (TieredCompilation) {
1818 MethodData* const mdo = method_data();
1819 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1820 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1821 return InvocationCounter::count_limit;
1822 } else {
1823 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1824 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1825 }
1826 } else {
1827 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1828 }
1829 }
1830
1831 int Method::backedge_count() {
1832 MethodCounters *mcs = method_counters();
1833 if (TieredCompilation) {
1834 MethodData* const mdo = method_data();
1835 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1836 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1837 return InvocationCounter::count_limit;
1838 } else {
1839 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1840 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1841 }
1842 } else {
1843 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1844 }
1845 }
1846
1847 int Method::highest_comp_level() const {
1848 const MethodCounters* mcs = method_counters();
1849 if (mcs != NULL) {
1850 return mcs->highest_comp_level();
1851 } else {
1852 return CompLevel_none;
1853 }
1854 }
1855
1856 int Method::highest_osr_comp_level() const {
1857 const MethodCounters* mcs = method_counters();
1858 if (mcs != NULL) {
1859 return mcs->highest_osr_comp_level();
1860 } else {
1861 return CompLevel_none;
1862 }
1863 }
1864
1865 void Method::set_highest_comp_level(int level) {
1866 MethodCounters* mcs = method_counters();
1867 if (mcs != NULL) {
1868 mcs->set_highest_comp_level(level);
1869 }
1870 }
1871
1872 void Method::set_highest_osr_comp_level(int level) {
1873 MethodCounters* mcs = method_counters();
1874 if (mcs != NULL) {
1875 mcs->set_highest_osr_comp_level(level);
1876 }
1877 }
1878
1879 #if INCLUDE_JVMTI
1880
1881 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1882 _bci = bci;
1883 _name_index = m->name_index();
1884 _signature_index = m->signature_index();
1885 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1886 if (_orig_bytecode == Bytecodes::_breakpoint)
1887 _orig_bytecode = m->orig_bytecode_at(_bci);
1888 _next = NULL;
1889 }
1890
1891 void BreakpointInfo::set(Method* method) {
1892 #ifdef ASSERT
1893 {
1894 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1895 if (code == Bytecodes::_breakpoint)
1896 code = method->orig_bytecode_at(_bci);
1897 assert(orig_bytecode() == code, "original bytecode must be the same");
1898 }
1899 #endif
1900 Thread *thread = Thread::current();
1901 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1902 method->incr_number_of_breakpoints(thread);
1903 SystemDictionary::notice_modification();
1904 {
1905 // Deoptimize all dependents on this method
1906 HandleMark hm(thread);
1907 methodHandle mh(thread, method);
1908 CodeCache::flush_dependents_on_method(mh);
1909 }
1910 }
1911
1912 void BreakpointInfo::clear(Method* method) {
1913 *method->bcp_from(_bci) = orig_bytecode();
1914 assert(method->number_of_breakpoints() > 0, "must not go negative");
1915 method->decr_number_of_breakpoints(Thread::current());
1916 }
1917
1918 #endif // INCLUDE_JVMTI
1919
1920 // jmethodID handling
1921
1922 // This is a block allocating object, sort of like JNIHandleBlock, only a
1923 // lot simpler.
1924 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1925 // never get rid of it.
1926
1927 static const int min_block_size = 8;
1928
1929 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1930 friend class JNIMethodBlock;
1931 Method** _methods;
1932 int _number_of_methods;
1933 int _top;
1934 JNIMethodBlockNode* _next;
1935
1936 public:
1937
1938 JNIMethodBlockNode(int num_methods = min_block_size);
1939
1940 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1941
1942 void ensure_methods(int num_addl_methods) {
1943 if (_top < _number_of_methods) {
1944 num_addl_methods -= _number_of_methods - _top;
1945 if (num_addl_methods <= 0) {
1946 return;
1947 }
1948 }
1949 if (_next == NULL) {
1950 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1951 } else {
1952 _next->ensure_methods(num_addl_methods);
1953 }
1954 }
1955 };
1956
1957 class JNIMethodBlock : public CHeapObj<mtClass> {
1958 JNIMethodBlockNode _head;
1959 JNIMethodBlockNode *_last_free;
1960 public:
1961 static Method* const _free_method;
1962
1963 JNIMethodBlock(int initial_capacity = min_block_size)
1964 : _head(initial_capacity), _last_free(&_head) {}
1965
1966 void ensure_methods(int num_addl_methods) {
1967 _last_free->ensure_methods(num_addl_methods);
1968 }
1969
1970 Method** add_method(Method* m) {
1971 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1972 if (b->_top < b->_number_of_methods) {
1973 // top points to the next free entry.
1974 int i = b->_top;
1975 b->_methods[i] = m;
1976 b->_top++;
1977 _last_free = b;
1978 return &(b->_methods[i]);
1979 } else if (b->_top == b->_number_of_methods) {
1980 // if the next free entry ran off the block see if there's a free entry
1981 for (int i = 0; i < b->_number_of_methods; i++) {
1982 if (b->_methods[i] == _free_method) {
1983 b->_methods[i] = m;
1984 _last_free = b;
1985 return &(b->_methods[i]);
1986 }
1987 }
1988 // Only check each block once for frees. They're very unlikely.
1989 // Increment top past the end of the block.
1990 b->_top++;
1991 }
1992 // need to allocate a next block.
1993 if (b->_next == NULL) {
1994 b->_next = _last_free = new JNIMethodBlockNode();
1995 }
1996 }
1997 guarantee(false, "Should always allocate a free block");
1998 return NULL;
1999 }
2000
2001 bool contains(Method** m) {
2002 if (m == NULL) return false;
2003 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2004 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2005 // This is a bit of extra checking, for two reasons. One is
2006 // that contains() deals with pointers that are passed in by
2007 // JNI code, so making sure that the pointer is aligned
2008 // correctly is valuable. The other is that <= and > are
2009 // technically not defined on pointers, so the if guard can
2010 // pass spuriously; no modern compiler is likely to make that
2011 // a problem, though (and if one did, the guard could also
2012 // fail spuriously, which would be bad).
2013 ptrdiff_t idx = m - b->_methods;
2014 if (b->_methods + idx == m) {
2015 return true;
2016 }
2017 }
2018 }
2019 return false; // not found
2020 }
2021
2022 // Doesn't really destroy it, just marks it as free so it can be reused.
2023 void destroy_method(Method** m) {
2024 #ifdef ASSERT
2025 assert(contains(m), "should be a methodID");
2026 #endif // ASSERT
2027 *m = _free_method;
2028 }
2029
2030 // During class unloading the methods are cleared, which is different
2031 // than freed.
2032 void clear_all_methods() {
2033 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2034 for (int i = 0; i< b->_number_of_methods; i++) {
2035 b->_methods[i] = NULL;
2036 }
2037 }
2038 }
2039 #ifndef PRODUCT
2040 int count_methods() {
2041 // count all allocated methods
2042 int count = 0;
2043 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2044 for (int i = 0; i< b->_number_of_methods; i++) {
2045 if (b->_methods[i] != _free_method) count++;
2046 }
2047 }
2048 return count;
2049 }
2050 #endif // PRODUCT
2051 };
2052
2053 // Something that can't be mistaken for an address or a markOop
2054 Method* const JNIMethodBlock::_free_method = (Method*)55;
2055
2056 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2057 _number_of_methods = MAX2(num_methods, min_block_size);
2058 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2059 for (int i = 0; i < _number_of_methods; i++) {
2060 _methods[i] = JNIMethodBlock::_free_method;
2061 }
2062 }
2063
2064 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2065 ClassLoaderData* cld = loader_data;
2066 if (!SafepointSynchronize::is_at_safepoint()) {
2067 // Have to add jmethod_ids() to class loader data thread-safely.
2068 // Also have to add the method to the list safely, which the cld lock
2069 // protects as well.
2070 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2071 if (cld->jmethod_ids() == NULL) {
2072 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2073 } else {
2074 cld->jmethod_ids()->ensure_methods(capacity);
2075 }
2076 } else {
2077 // At safepoint, we are single threaded and can set this.
2078 if (cld->jmethod_ids() == NULL) {
2079 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2080 } else {
2081 cld->jmethod_ids()->ensure_methods(capacity);
2082 }
2083 }
2084 }
2085
2086 // Add a method id to the jmethod_ids
2087 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2088 ClassLoaderData* cld = loader_data;
2089
2090 if (!SafepointSynchronize::is_at_safepoint()) {
2091 // Have to add jmethod_ids() to class loader data thread-safely.
2092 // Also have to add the method to the list safely, which the cld lock
2093 // protects as well.
2094 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2095 if (cld->jmethod_ids() == NULL) {
2096 cld->set_jmethod_ids(new JNIMethodBlock());
2097 }
2098 // jmethodID is a pointer to Method*
2099 return (jmethodID)cld->jmethod_ids()->add_method(m);
2100 } else {
2101 // At safepoint, we are single threaded and can set this.
2102 if (cld->jmethod_ids() == NULL) {
2103 cld->set_jmethod_ids(new JNIMethodBlock());
2104 }
2105 // jmethodID is a pointer to Method*
2106 return (jmethodID)cld->jmethod_ids()->add_method(m);
2107 }
2108 }
2109
2110 // Mark a jmethodID as free. This is called when there is a data race in
2111 // InstanceKlass while creating the jmethodID cache.
2112 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2113 ClassLoaderData* cld = loader_data;
2114 Method** ptr = (Method**)m;
2115 assert(cld->jmethod_ids() != NULL, "should have method handles");
2116 cld->jmethod_ids()->destroy_method(ptr);
2117 }
2118
2119 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2120 // Can't assert the method_holder is the same because the new method has the
2121 // scratch method holder.
2122 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2123 == new_method->method_holder()->class_loader() ||
2124 new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2125 "changing to a different class loader");
2126 // Just change the method in place, jmethodID pointer doesn't change.
2127 *((Method**)jmid) = new_method;
2128 }
2129
2130 bool Method::is_method_id(jmethodID mid) {
2131 Method* m = resolve_jmethod_id(mid);
2132 assert(m != NULL, "should be called with non-null method");
2133 InstanceKlass* ik = m->method_holder();
2134 ClassLoaderData* cld = ik->class_loader_data();
2135 if (cld->jmethod_ids() == NULL) return false;
2136 return (cld->jmethod_ids()->contains((Method**)mid));
2137 }
2138
2139 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2140 if (mid == NULL) return NULL;
2141 Method* o = resolve_jmethod_id(mid);
2142 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2143 return NULL;
2144 }
2145 return o;
2146 };
2147
2148 void Method::set_on_stack(const bool value) {
2149 // Set both the method itself and its constant pool. The constant pool
2150 // on stack means some method referring to it is also on the stack.
2151 constants()->set_on_stack(value);
2152
2153 bool already_set = on_stack();
2154 _access_flags.set_on_stack(value);
2155 if (value && !already_set) {
2156 MetadataOnStackMark::record(this);
2157 }
2158 assert(!value || !is_old() || is_obsolete() || is_running_emcp(),
2159 "emcp methods cannot run after emcp bit is cleared");
2160 }
2161
2162 // Called when the class loader is unloaded to make all methods weak.
2163 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2164 loader_data->jmethod_ids()->clear_all_methods();
2165 }
2166
2167 bool Method::has_method_vptr(const void* ptr) {
2168 Method m;
2169 // This assumes that the vtbl pointer is the first word of a C++ object.
2170 return dereference_vptr(&m) == dereference_vptr(ptr);
2171 }
2172
2173 // Check that this pointer is valid by checking that the vtbl pointer matches
2174 bool Method::is_valid_method(const Method* m) {
2175 if (m == NULL) {
2176 return false;
2177 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2178 // Quick sanity check on pointer.
2179 return false;
2180 } else if (m->is_shared()) {
2181 return MetaspaceShared::is_valid_shared_method(m);
2182 } else if (Metaspace::contains_non_shared(m)) {
2183 return has_method_vptr((const void*)m);
2184 } else {
2185 return false;
2186 }
2187 }
2188
2189 #ifndef PRODUCT
2190 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2191 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2192 }
2193 #endif // PRODUCT
2194
2195
2196 // Printing
2197
2198 #ifndef PRODUCT
2199
2200 void Method::print_on(outputStream* st) const {
2201 ResourceMark rm;
2202 assert(is_method(), "must be method");
2203 st->print_cr("%s", internal_name());
2204 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2205 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2206 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2207 constants()->print_value_on(st); st->cr();
2208 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2209 st->print (" - name: "); name()->print_value_on(st); st->cr();
2210 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2211 st->print_cr(" - max stack: %d", max_stack());
2212 st->print_cr(" - max locals: %d", max_locals());
2213 st->print_cr(" - size of params: %d", size_of_parameters());
2214 st->print_cr(" - method size: %d", method_size());
2215 if (intrinsic_id() != vmIntrinsics::_none)
2216 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2217 if (highest_comp_level() != CompLevel_none)
2218 st->print_cr(" - highest level: %d", highest_comp_level());
2219 st->print_cr(" - vtable index: %d", _vtable_index);
2220 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2221 st->print( " - adapters: ");
2222 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2223 if (a == NULL)
2224 st->print_cr(INTPTR_FORMAT, p2i(a));
2225 else
2226 a->print_adapter_on(st);
2227 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2228 st->print_cr(" - code size: %d", code_size());
2229 if (code_size() != 0) {
2230 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2231 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2232 }
2233 if (method_data() != NULL) {
2234 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2235 }
2236 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2237 if (checked_exceptions_length() > 0) {
2238 CheckedExceptionElement* table = checked_exceptions_start();
2239 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2240 if (Verbose) {
2241 for (int i = 0; i < checked_exceptions_length(); i++) {
2242 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2243 }
2244 }
2245 }
2246 if (has_linenumber_table()) {
2247 u_char* table = compressed_linenumber_table();
2248 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2249 if (Verbose) {
2250 CompressedLineNumberReadStream stream(table);
2251 while (stream.read_pair()) {
2252 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2253 }
2254 }
2255 }
2256 st->print_cr(" - localvar length: %d", localvariable_table_length());
2257 if (localvariable_table_length() > 0) {
2258 LocalVariableTableElement* table = localvariable_table_start();
2259 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2260 if (Verbose) {
2261 for (int i = 0; i < localvariable_table_length(); i++) {
2262 int bci = table[i].start_bci;
2263 int len = table[i].length;
2264 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2265 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2266 int slot = table[i].slot;
2267 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2268 }
2269 }
2270 }
2271 if (code() != NULL) {
2272 st->print (" - compiled code: ");
2273 code()->print_value_on(st);
2274 }
2275 if (is_native()) {
2276 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2277 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2278 }
2279 }
2280
2281 void Method::print_linkage_flags(outputStream* st) {
2282 access_flags().print_on(st);
2283 if (is_default_method()) {
2284 st->print("default ");
2285 }
2286 if (is_overpass()) {
2287 st->print("overpass ");
2288 }
2289 }
2290 #endif //PRODUCT
2291
2292 void Method::print_value_on(outputStream* st) const {
2293 assert(is_method(), "must be method");
2294 st->print("%s", internal_name());
2295 print_address_on(st);
2296 st->print(" ");
2297 name()->print_value_on(st);
2298 st->print(" ");
2299 signature()->print_value_on(st);
2300 st->print(" in ");
2301 method_holder()->print_value_on(st);
2302 if (WizardMode) st->print("#%d", _vtable_index);
2303 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2304 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2305 }
2306
2307 #if INCLUDE_SERVICES
2308 // Size Statistics
2309 void Method::collect_statistics(KlassSizeStats *sz) const {
2310 int mysize = sz->count(this);
2311 sz->_method_bytes += mysize;
2312 sz->_method_all_bytes += mysize;
2313 sz->_rw_bytes += mysize;
2314
2315 if (constMethod()) {
2316 constMethod()->collect_statistics(sz);
2317 }
2318 if (method_data()) {
2319 method_data()->collect_statistics(sz);
2320 }
2321 }
2322 #endif // INCLUDE_SERVICES
2323
2324 // LogTouchedMethods and PrintTouchedMethods
2325
2326 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2327 // the Method may be garbage collected. Let's roll our own hash table.
2328 class TouchedMethodRecord : CHeapObj<mtTracing> {
2329 public:
2330 // It's OK to store Symbols here because they will NOT be GC'ed if
2331 // LogTouchedMethods is enabled.
2332 TouchedMethodRecord* _next;
2333 Symbol* _class_name;
2334 Symbol* _method_name;
2335 Symbol* _method_signature;
2336 };
2337
2338 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2339 static TouchedMethodRecord** _touched_method_table = NULL;
2340
2341 void Method::log_touched(TRAPS) {
2342
2343 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2344 Symbol* my_class = klass_name();
2345 Symbol* my_name = name();
2346 Symbol* my_sig = signature();
2347
2348 unsigned int hash = my_class->identity_hash() +
2349 my_name->identity_hash() +
2350 my_sig->identity_hash();
2351 juint index = juint(hash) % table_size;
2352
2353 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2354 if (_touched_method_table == NULL) {
2355 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2356 mtTracing, CURRENT_PC);
2357 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2358 }
2359
2360 TouchedMethodRecord* ptr = _touched_method_table[index];
2361 while (ptr) {
2362 if (ptr->_class_name == my_class &&
2363 ptr->_method_name == my_name &&
2364 ptr->_method_signature == my_sig) {
2365 return;
2366 }
2367 if (ptr->_next == NULL) break;
2368 ptr = ptr->_next;
2369 }
2370 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2371 my_class->increment_refcount();
2372 my_name->increment_refcount();
2373 my_sig->increment_refcount();
2374 nptr->_class_name = my_class;
2375 nptr->_method_name = my_name;
2376 nptr->_method_signature = my_sig;
2377 nptr->_next = NULL;
2378
2379 if (ptr == NULL) {
2380 // first
2381 _touched_method_table[index] = nptr;
2382 } else {
2383 ptr->_next = nptr;
2384 }
2385 }
2386
2387 void Method::print_touched_methods(outputStream* out) {
2388 MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2389 out->print_cr("# Method::print_touched_methods version 1");
2390 if (_touched_method_table) {
2391 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2392 TouchedMethodRecord* ptr = _touched_method_table[i];
2393 while(ptr) {
2394 ptr->_class_name->print_symbol_on(out); out->print(".");
2395 ptr->_method_name->print_symbol_on(out); out->print(":");
2396 ptr->_method_signature->print_symbol_on(out); out->cr();
2397 ptr = ptr->_next;
2398 }
2399 }
2400 }
2401 }
2402
2403 // Verification
2404
2405 void Method::verify_on(outputStream* st) {
2406 guarantee(is_method(), "object must be method");
2407 guarantee(constants()->is_constantPool(), "should be constant pool");
2408 MethodData* md = method_data();
2409 guarantee(md == NULL ||
2410 md->is_methodData(), "should be method data");
2411 }