1 /*
2 * Copyright (c) 1997, 2020, 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/symbolTable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "code/codeCache.hpp"
31 #include "code/debugInfoRec.hpp"
32 #include "compiler/compilationPolicy.hpp"
33 #include "gc/shared/collectedHeap.inline.hpp"
34 #include "interpreter/bytecodeStream.hpp"
35 #include "interpreter/bytecodeTracer.hpp"
36 #include "interpreter/bytecodes.hpp"
37 #include "interpreter/interpreter.hpp"
38 #include "interpreter/oopMapCache.hpp"
39 #include "logging/log.hpp"
40 #include "logging/logTag.hpp"
41 #include "memory/allocation.inline.hpp"
42 #include "memory/metadataFactory.hpp"
43 #include "memory/metaspaceClosure.hpp"
44 #include "memory/metaspaceShared.hpp"
45 #include "memory/oopFactory.hpp"
46 #include "memory/resourceArea.hpp"
47 #include "memory/universe.hpp"
48 #include "oops/constMethod.hpp"
49 #include "oops/constantPool.hpp"
50 #include "oops/method.inline.hpp"
51 #include "oops/methodData.hpp"
52 #include "oops/objArrayKlass.hpp"
53 #include "oops/objArrayOop.inline.hpp"
54 #include "oops/oop.inline.hpp"
55 #include "oops/symbol.hpp"
56 #include "prims/jvmtiExport.hpp"
57 #include "prims/methodHandles.hpp"
58 #include "prims/nativeLookup.hpp"
59 #include "runtime/arguments.hpp"
60 #include "runtime/atomic.hpp"
61 #include "runtime/frame.inline.hpp"
62 #include "runtime/handles.inline.hpp"
63 #include "runtime/init.hpp"
64 #include "runtime/orderAccess.hpp"
65 #include "runtime/relocator.hpp"
66 #include "runtime/safepointVerifiers.hpp"
67 #include "runtime/sharedRuntime.hpp"
68 #include "runtime/signature.hpp"
69 #include "utilities/align.hpp"
70 #include "utilities/quickSort.hpp"
71 #include "utilities/vmError.hpp"
72 #include "utilities/xmlstream.hpp"
73
74 // Implementation of Method
75
76 Method* Method::allocate(ClassLoaderData* loader_data,
77 int byte_code_size,
78 AccessFlags access_flags,
79 InlineTableSizes* sizes,
80 ConstMethod::MethodType method_type,
81 TRAPS) {
82 assert(!access_flags.is_native() || byte_code_size == 0,
83 "native methods should not contain byte codes");
84 ConstMethod* cm = ConstMethod::allocate(loader_data,
85 byte_code_size,
86 sizes,
87 method_type,
88 CHECK_NULL);
89 int size = Method::size(access_flags.is_native());
90 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
91 }
92
93 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
94 NoSafepointVerifier no_safepoint;
95 set_constMethod(xconst);
96 set_access_flags(access_flags);
97 set_intrinsic_id(vmIntrinsics::_none);
98 set_force_inline(false);
99 set_hidden(false);
100 set_dont_inline(false);
101 set_has_injected_profile(false);
102 set_method_data(NULL);
103 clear_method_counters();
104 set_vtable_index(Method::garbage_vtable_index);
105
106 // Fix and bury in Method*
107 set_interpreter_entry(NULL); // sets i2i entry and from_int
108 set_adapter_entry(NULL);
109 Method::clear_code(); // from_c/from_i get set to c2i/i2i
110
111 if (access_flags.is_native()) {
112 clear_native_function();
113 set_signature_handler(NULL);
114 }
115
116 NOT_PRODUCT(set_compiled_invocation_count(0);)
117 }
118
119 // Release Method*. The nmethod will be gone when we get here because
120 // we've walked the code cache.
121 void Method::deallocate_contents(ClassLoaderData* loader_data) {
122 MetadataFactory::free_metadata(loader_data, constMethod());
123 set_constMethod(NULL);
124 MetadataFactory::free_metadata(loader_data, method_data());
125 set_method_data(NULL);
126 MetadataFactory::free_metadata(loader_data, method_counters());
127 clear_method_counters();
128 // The nmethod will be gone when we get here.
129 if (code() != NULL) _code = NULL;
130 }
131
132 void Method::release_C_heap_structures() {
133 if (method_data()) {
134 #if INCLUDE_JVMCI
135 FailedSpeculation::free_failed_speculations(method_data()->get_failed_speculations_address());
136 #endif
137 // Destroy MethodData
138 method_data()->~MethodData();
139 }
140 }
141
142 address Method::get_i2c_entry() {
143 assert(adapter() != NULL, "must have");
144 return adapter()->get_i2c_entry();
145 }
146
147 address Method::get_c2i_entry() {
148 assert(adapter() != NULL, "must have");
149 return adapter()->get_c2i_entry();
150 }
151
152 address Method::get_c2i_unverified_entry() {
153 assert(adapter() != NULL, "must have");
154 return adapter()->get_c2i_unverified_entry();
155 }
156
157 address Method::get_c2i_no_clinit_check_entry() {
158 assert(VM_Version::supports_fast_class_init_checks(), "");
159 assert(adapter() != NULL, "must have");
160 return adapter()->get_c2i_no_clinit_check_entry();
161 }
162
163 char* Method::name_and_sig_as_C_string() const {
164 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
165 }
166
167 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
168 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
169 }
170
171 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
172 const char* klass_name = klass->external_name();
173 int klass_name_len = (int)strlen(klass_name);
174 int method_name_len = method_name->utf8_length();
175 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
176 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
177 strcpy(dest, klass_name);
178 dest[klass_name_len] = '.';
179 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
180 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
181 dest[len] = 0;
182 return dest;
183 }
184
185 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
186 Symbol* klass_name = klass->name();
187 klass_name->as_klass_external_name(buf, size);
188 int len = (int)strlen(buf);
189
190 if (len < size - 1) {
191 buf[len++] = '.';
192
193 method_name->as_C_string(&(buf[len]), size - len);
194 len = (int)strlen(buf);
195
196 signature->as_C_string(&(buf[len]), size - len);
197 }
198
199 return buf;
200 }
201
202 const char* Method::external_name() const {
203 return external_name(constants()->pool_holder(), name(), signature());
204 }
205
206 void Method::print_external_name(outputStream *os) const {
207 print_external_name(os, constants()->pool_holder(), name(), signature());
208 }
209
210 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
211 stringStream ss;
212 print_external_name(&ss, klass, method_name, signature);
213 return ss.as_string();
214 }
215
216 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
217 signature->print_as_signature_external_return_type(os);
218 os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
219 signature->print_as_signature_external_parameters(os);
220 os->print(")");
221 }
222
223 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
224 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
225 // access exception table
226 ExceptionTable table(mh());
227 int length = table.length();
228 // iterate through all entries sequentially
229 constantPoolHandle pool(THREAD, mh->constants());
230 for (int i = 0; i < length; i ++) {
231 //reacquire the table in case a GC happened
232 ExceptionTable table(mh());
233 int beg_bci = table.start_pc(i);
234 int end_bci = table.end_pc(i);
235 assert(beg_bci <= end_bci, "inconsistent exception table");
236 if (beg_bci <= throw_bci && throw_bci < end_bci) {
237 // exception handler bci range covers throw_bci => investigate further
238 int handler_bci = table.handler_pc(i);
239 int klass_index = table.catch_type_index(i);
240 if (klass_index == 0) {
241 return handler_bci;
242 } else if (ex_klass == NULL) {
243 return handler_bci;
244 } else {
245 // we know the exception class => get the constraint class
246 // this may require loading of the constraint class; if verification
247 // fails or some other exception occurs, return handler_bci
248 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
249 assert(k != NULL, "klass not loaded");
250 if (ex_klass->is_subtype_of(k)) {
251 return handler_bci;
252 }
253 }
254 }
255 }
256
257 return -1;
258 }
259
260 void Method::mask_for(int bci, InterpreterOopMap* mask) {
261 methodHandle h_this(Thread::current(), this);
262 // Only GC uses the OopMapCache during thread stack root scanning
263 // any other uses generate an oopmap but do not save it in the cache.
264 if (Universe::heap()->is_gc_active()) {
265 method_holder()->mask_for(h_this, bci, mask);
266 } else {
267 OopMapCache::compute_one_oop_map(h_this, bci, mask);
268 }
269 return;
270 }
271
272
273 int Method::bci_from(address bcp) const {
274 if (is_native() && bcp == 0) {
275 return 0;
276 }
277 #ifdef ASSERT
278 {
279 ResourceMark rm;
280 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
281 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
282 p2i(bcp), name_and_sig_as_C_string());
283 }
284 #endif
285 return bcp - code_base();
286 }
287
288
289 int Method::validate_bci(int bci) const {
290 return (bci == 0 || bci < code_size()) ? bci : -1;
291 }
292
293 // Return bci if it appears to be a valid bcp
294 // Return -1 otherwise.
295 // Used by profiling code, when invalid data is a possibility.
296 // The caller is responsible for validating the Method* itself.
297 int Method::validate_bci_from_bcp(address bcp) const {
298 // keep bci as -1 if not a valid bci
299 int bci = -1;
300 if (bcp == 0 || bcp == code_base()) {
301 // code_size() may return 0 and we allow 0 here
302 // the method may be native
303 bci = 0;
304 } else if (contains(bcp)) {
305 bci = bcp - code_base();
306 }
307 // Assert that if we have dodged any asserts, bci is negative.
308 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
309 return bci;
310 }
311
312 address Method::bcp_from(int bci) const {
313 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
314 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
315 address bcp = code_base() + bci;
316 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
317 return bcp;
318 }
319
320 address Method::bcp_from(address bcp) const {
321 if (is_native() && bcp == NULL) {
322 return code_base();
323 } else {
324 return bcp;
325 }
326 }
327
328 int Method::size(bool is_native) {
329 // If native, then include pointers for native_function and signature_handler
330 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
331 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
332 return align_metadata_size(header_size() + extra_words);
333 }
334
335 Symbol* Method::klass_name() const {
336 return method_holder()->name();
337 }
338
339 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
340 log_trace(cds)("Iter(Method): %p", this);
341
342 it->push(&_constMethod);
343 it->push(&_method_data);
344 it->push(&_method_counters);
345
346 Method* this_ptr = this;
347 it->push_method_entry(&this_ptr, (intptr_t*)&_i2i_entry);
348 it->push_method_entry(&this_ptr, (intptr_t*)&_from_compiled_entry);
349 it->push_method_entry(&this_ptr, (intptr_t*)&_from_interpreted_entry);
350 }
351
352 // Attempt to return method oop to original state. Clear any pointers
353 // (to objects outside the shared spaces). We won't be able to predict
354 // where they should point in a new JVM. Further initialize some
355 // entries now in order allow them to be write protected later.
356
357 void Method::remove_unshareable_info() {
358 unlink_method();
359 }
360
361 void Method::set_vtable_index(int index) {
362 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
363 // At runtime initialize_vtable is rerun as part of link_class_impl()
364 // for a shared class loaded by the non-boot loader to obtain the loader
365 // constraints based on the runtime classloaders' context.
366 return; // don't write into the shared class
367 } else {
368 _vtable_index = index;
369 }
370 }
371
372 void Method::set_itable_index(int index) {
373 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
374 // At runtime initialize_itable is rerun as part of link_class_impl()
375 // for a shared class loaded by the non-boot loader to obtain the loader
376 // constraints based on the runtime classloaders' context. The dumptime
377 // itable index should be the same as the runtime index.
378 assert(_vtable_index == itable_index_max - index,
379 "archived itable index is different from runtime index");
380 return; // don’t write into the shared class
381 } else {
382 _vtable_index = itable_index_max - index;
383 }
384 assert(valid_itable_index(), "");
385 }
386
387 // The RegisterNatives call being attempted tried to register with a method that
388 // is not native. Ask JVM TI what prefixes have been specified. Then check
389 // to see if the native method is now wrapped with the prefixes. See the
390 // SetNativeMethodPrefix(es) functions in the JVM TI Spec for details.
391 static Method* find_prefixed_native(Klass* k, Symbol* name, Symbol* signature, TRAPS) {
392 #if INCLUDE_JVMTI
393 ResourceMark rm(THREAD);
394 Method* method;
395 int name_len = name->utf8_length();
396 char* name_str = name->as_utf8();
397 int prefix_count;
398 char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
399 for (int i = 0; i < prefix_count; i++) {
400 char* prefix = prefixes[i];
401 int prefix_len = (int)strlen(prefix);
402
403 // try adding this prefix to the method name and see if it matches another method name
404 int trial_len = name_len + prefix_len;
405 char* trial_name_str = NEW_RESOURCE_ARRAY(char, trial_len + 1);
406 strcpy(trial_name_str, prefix);
407 strcat(trial_name_str, name_str);
408 TempNewSymbol trial_name = SymbolTable::probe(trial_name_str, trial_len);
409 if (trial_name == NULL) {
410 continue; // no such symbol, so this prefix wasn't used, try the next prefix
411 }
412 method = k->lookup_method(trial_name, signature);
413 if (method == NULL) {
414 continue; // signature doesn't match, try the next prefix
415 }
416 if (method->is_native()) {
417 method->set_is_prefixed_native();
418 return method; // wahoo, we found a prefixed version of the method, return it
419 }
420 // found as non-native, so prefix is good, add it, probably just need more prefixes
421 name_len = trial_len;
422 name_str = trial_name_str;
423 }
424 #endif // INCLUDE_JVMTI
425 return NULL; // not found
426 }
427
428 bool Method::register_native(Klass* k, Symbol* name, Symbol* signature, address entry, TRAPS) {
429 Method* method = k->lookup_method(name, signature);
430 if (method == NULL) {
431 ResourceMark rm(THREAD);
432 stringStream st;
433 st.print("Method '");
434 print_external_name(&st, k, name, signature);
435 st.print("' name or signature does not match");
436 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
437 }
438 if (!method->is_native()) {
439 // trying to register to a non-native method, see if a JVM TI agent has added prefix(es)
440 method = find_prefixed_native(k, name, signature, THREAD);
441 if (method == NULL) {
442 ResourceMark rm(THREAD);
443 stringStream st;
444 st.print("Method '");
445 print_external_name(&st, k, name, signature);
446 st.print("' is not declared as native");
447 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
448 }
449 }
450
451 if (entry != NULL) {
452 method->set_native_function(entry, native_bind_event_is_interesting);
453 } else {
454 method->clear_native_function();
455 }
456 if (log_is_enabled(Debug, jni, resolve)) {
457 ResourceMark rm(THREAD);
458 log_debug(jni, resolve)("[Registering JNI native method %s.%s]",
459 method->method_holder()->external_name(),
460 method->name()->as_C_string());
461 }
462 return true;
463 }
464
465 bool Method::was_executed_more_than(int n) {
466 // Invocation counter is reset when the Method* is compiled.
467 // If the method has compiled code we therefore assume it has
468 // be excuted more than n times.
469 if (is_accessor() || is_empty_method() || (code() != NULL)) {
470 // interpreter doesn't bump invocation counter of trivial methods
471 // compiler does not bump invocation counter of compiled methods
472 return true;
473 }
474 else if ((method_counters() != NULL &&
475 method_counters()->invocation_counter()->carry()) ||
476 (method_data() != NULL &&
477 method_data()->invocation_counter()->carry())) {
478 // The carry bit is set when the counter overflows and causes
479 // a compilation to occur. We don't know how many times
480 // the counter has been reset, so we simply assume it has
481 // been executed more than n times.
482 return true;
483 } else {
484 return invocation_count() > n;
485 }
486 }
487
488 void Method::print_invocation_count() {
489 if (is_static()) tty->print("static ");
490 if (is_final()) tty->print("final ");
491 if (is_synchronized()) tty->print("synchronized ");
492 if (is_native()) tty->print("native ");
493 tty->print("%s::", method_holder()->external_name());
494 name()->print_symbol_on(tty);
495 signature()->print_symbol_on(tty);
496
497 if (WizardMode) {
498 // dump the size of the byte codes
499 tty->print(" {%d}", code_size());
500 }
501 tty->cr();
502
503 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count());
504 tty->print_cr (" invocation_counter: %8d ", invocation_count());
505 tty->print_cr (" backedge_counter: %8d ", backedge_count());
506 #ifndef PRODUCT
507 if (CountCompiledCalls) {
508 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count());
509 }
510 #endif
511 }
512
513 // Build a MethodData* object to hold information about this method
514 // collected in the interpreter.
515 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
516 // Do not profile the method if metaspace has hit an OOM previously
517 // allocating profiling data. Callers clear pending exception so don't
518 // add one here.
519 if (ClassLoaderDataGraph::has_metaspace_oom()) {
520 return;
521 }
522
523 // Grab a lock here to prevent multiple
524 // MethodData*s from being created.
525 MutexLocker ml(THREAD, MethodData_lock);
526 if (method->method_data() == NULL) {
527 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
528 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
529 if (HAS_PENDING_EXCEPTION) {
530 CompileBroker::log_metaspace_failure();
531 ClassLoaderDataGraph::set_metaspace_oom(true);
532 return; // return the exception (which is cleared)
533 }
534
535 method->set_method_data(method_data);
536 if (PrintMethodData && (Verbose || WizardMode)) {
537 ResourceMark rm(THREAD);
538 tty->print("build_interpreter_method_data for ");
539 method->print_name(tty);
540 tty->cr();
541 // At the end of the run, the MDO, full of data, will be dumped.
542 }
543 }
544 }
545
546 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
547 // Do not profile the method if metaspace has hit an OOM previously
548 if (ClassLoaderDataGraph::has_metaspace_oom()) {
549 return NULL;
550 }
551
552 methodHandle mh(THREAD, m);
553 MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
554 if (HAS_PENDING_EXCEPTION) {
555 CompileBroker::log_metaspace_failure();
556 ClassLoaderDataGraph::set_metaspace_oom(true);
557 return NULL; // return the exception (which is cleared)
558 }
559 if (!mh->init_method_counters(counters)) {
560 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
561 }
562
563 if (LogTouchedMethods) {
564 mh->log_touched(CHECK_NULL);
565 }
566
567 return mh->method_counters();
568 }
569
570 bool Method::init_method_counters(MethodCounters* counters) {
571 // Try to install a pointer to MethodCounters, return true on success.
572 return Atomic::replace_if_null(&_method_counters, counters);
573 }
574
575 int Method::extra_stack_words() {
576 // not an inline function, to avoid a header dependency on Interpreter
577 return extra_stack_entries() * Interpreter::stackElementSize;
578 }
579
580 // Derive size of parameters, return type, and fingerprint,
581 // all in one pass, which is run at load time.
582 // We need the first two, and might as well grab the third.
583 void Method::compute_from_signature(Symbol* sig) {
584 // At this point, since we are scanning the signature,
585 // we might as well compute the whole fingerprint.
586 Fingerprinter fp(sig, is_static());
587 set_size_of_parameters(fp.size_of_parameters());
588 constMethod()->set_result_type(fp.return_type());
589 constMethod()->set_fingerprint(fp.fingerprint());
590 }
591
592 bool Method::is_empty_method() const {
593 return code_size() == 1
594 && *code_base() == Bytecodes::_return;
595 }
596
597 bool Method::is_vanilla_constructor() const {
598 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
599 // which only calls the superclass vanilla constructor and possibly does stores of
600 // zero constants to local fields:
601 //
602 // aload_0
603 // invokespecial
604 // indexbyte1
605 // indexbyte2
606 //
607 // followed by an (optional) sequence of:
608 //
609 // aload_0
610 // aconst_null / iconst_0 / fconst_0 / dconst_0
611 // putfield
612 // indexbyte1
613 // indexbyte2
614 //
615 // followed by:
616 //
617 // return
618
619 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
620 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
621 int size = code_size();
622 // Check if size match
623 if (size == 0 || size % 5 != 0) return false;
624 address cb = code_base();
625 int last = size - 1;
626 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
627 // Does not call superclass default constructor
628 return false;
629 }
630 // Check optional sequence
631 for (int i = 4; i < last; i += 5) {
632 if (cb[i] != Bytecodes::_aload_0) return false;
633 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
634 if (cb[i+2] != Bytecodes::_putfield) return false;
635 }
636 return true;
637 }
638
639
640 bool Method::compute_has_loops_flag() {
641 BytecodeStream bcs(methodHandle(Thread::current(), this));
642 Bytecodes::Code bc;
643
644 while ((bc = bcs.next()) >= 0) {
645 switch( bc ) {
646 case Bytecodes::_ifeq:
647 case Bytecodes::_ifnull:
648 case Bytecodes::_iflt:
649 case Bytecodes::_ifle:
650 case Bytecodes::_ifne:
651 case Bytecodes::_ifnonnull:
652 case Bytecodes::_ifgt:
653 case Bytecodes::_ifge:
654 case Bytecodes::_if_icmpeq:
655 case Bytecodes::_if_icmpne:
656 case Bytecodes::_if_icmplt:
657 case Bytecodes::_if_icmpgt:
658 case Bytecodes::_if_icmple:
659 case Bytecodes::_if_icmpge:
660 case Bytecodes::_if_acmpeq:
661 case Bytecodes::_if_acmpne:
662 case Bytecodes::_goto:
663 case Bytecodes::_jsr:
664 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
665 break;
666
667 case Bytecodes::_goto_w:
668 case Bytecodes::_jsr_w:
669 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
670 break;
671
672 default:
673 break;
674 }
675 }
676 _access_flags.set_loops_flag_init();
677 return _access_flags.has_loops();
678 }
679
680 bool Method::is_final_method(AccessFlags class_access_flags) const {
681 // or "does_not_require_vtable_entry"
682 // default method or overpass can occur, is not final (reuses vtable entry)
683 // private methods in classes get vtable entries for backward class compatibility.
684 if (is_overpass() || is_default_method()) return false;
685 return is_final() || class_access_flags.is_final();
686 }
687
688 bool Method::is_final_method() const {
689 return is_final_method(method_holder()->access_flags());
690 }
691
692 bool Method::is_default_method() const {
693 if (method_holder() != NULL &&
694 method_holder()->is_interface() &&
695 !is_abstract() && !is_private()) {
696 return true;
697 } else {
698 return false;
699 }
700 }
701
702 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
703 if (is_final_method(class_access_flags)) return true;
704 #ifdef ASSERT
705 ResourceMark rm;
706 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
707 if (class_access_flags.is_interface()) {
708 assert(is_nonv == is_static() || is_nonv == is_private(),
709 "nonvirtual unexpected for non-static, non-private: %s",
710 name_and_sig_as_C_string());
711 }
712 #endif
713 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
714 return vtable_index() == nonvirtual_vtable_index;
715 }
716
717 bool Method::can_be_statically_bound() const {
718 return can_be_statically_bound(method_holder()->access_flags());
719 }
720
721 bool Method::can_be_statically_bound(InstanceKlass* context) const {
722 return (method_holder() == context) && can_be_statically_bound();
723 }
724
725 bool Method::is_accessor() const {
726 return is_getter() || is_setter();
727 }
728
729 bool Method::is_getter() const {
730 if (code_size() != 5) return false;
731 if (size_of_parameters() != 1) return false;
732 if (java_code_at(0) != Bytecodes::_aload_0) return false;
733 if (java_code_at(1) != Bytecodes::_getfield) return false;
734 switch (java_code_at(4)) {
735 case Bytecodes::_ireturn:
736 case Bytecodes::_lreturn:
737 case Bytecodes::_freturn:
738 case Bytecodes::_dreturn:
739 case Bytecodes::_areturn:
740 break;
741 default:
742 return false;
743 }
744 return true;
745 }
746
747 bool Method::is_setter() const {
748 if (code_size() != 6) return false;
749 if (java_code_at(0) != Bytecodes::_aload_0) return false;
750 switch (java_code_at(1)) {
751 case Bytecodes::_iload_1:
752 case Bytecodes::_aload_1:
753 case Bytecodes::_fload_1:
754 if (size_of_parameters() != 2) return false;
755 break;
756 case Bytecodes::_dload_1:
757 case Bytecodes::_lload_1:
758 if (size_of_parameters() != 3) return false;
759 break;
760 default:
761 return false;
762 }
763 if (java_code_at(2) != Bytecodes::_putfield) return false;
764 if (java_code_at(5) != Bytecodes::_return) return false;
765 return true;
766 }
767
768 bool Method::is_constant_getter() const {
769 int last_index = code_size() - 1;
770 // Check if the first 1-3 bytecodes are a constant push
771 // and the last bytecode is a return.
772 return (2 <= code_size() && code_size() <= 4 &&
773 Bytecodes::is_const(java_code_at(0)) &&
774 Bytecodes::length_for(java_code_at(0)) == last_index &&
775 Bytecodes::is_return(java_code_at(last_index)));
776 }
777
778 bool Method::is_initializer() const {
779 return is_object_initializer() || is_static_initializer();
780 }
781
782 bool Method::has_valid_initializer_flags() const {
783 return (is_static() ||
784 method_holder()->major_version() < 51);
785 }
786
787 bool Method::is_static_initializer() const {
788 // For classfiles version 51 or greater, ensure that the clinit method is
789 // static. Non-static methods with the name "<clinit>" are not static
790 // initializers. (older classfiles exempted for backward compatibility)
791 return name() == vmSymbols::class_initializer_name() &&
792 has_valid_initializer_flags();
793 }
794
795 bool Method::is_object_initializer() const {
796 return name() == vmSymbols::object_initializer_name();
797 }
798
799 bool Method::needs_clinit_barrier() const {
800 return is_static() && !method_holder()->is_initialized();
801 }
802
803 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
804 int length = method->checked_exceptions_length();
805 if (length == 0) { // common case
806 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
807 } else {
808 methodHandle h_this(THREAD, method);
809 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
810 objArrayHandle mirrors (THREAD, m_oop);
811 for (int i = 0; i < length; i++) {
812 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
813 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
814 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
815 mirrors->obj_at_put(i, k->java_mirror());
816 }
817 return mirrors;
818 }
819 };
820
821
822 int Method::line_number_from_bci(int bci) const {
823 int best_bci = 0;
824 int best_line = -1;
825 if (bci == SynchronizationEntryBCI) bci = 0;
826 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
827 // The line numbers are a short array of 2-tuples [start_pc, line_number].
828 // Not necessarily sorted and not necessarily one-to-one.
829 CompressedLineNumberReadStream stream(compressed_linenumber_table());
830 while (stream.read_pair()) {
831 if (stream.bci() == bci) {
832 // perfect match
833 return stream.line();
834 } else {
835 // update best_bci/line
836 if (stream.bci() < bci && stream.bci() >= best_bci) {
837 best_bci = stream.bci();
838 best_line = stream.line();
839 }
840 }
841 }
842 }
843 return best_line;
844 }
845
846
847 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
848 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
849 Thread *thread = Thread::current();
850 Symbol* klass_name = constants()->klass_name_at(klass_index);
851 Handle loader(thread, method_holder()->class_loader());
852 Handle prot (thread, method_holder()->protection_domain());
853 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
854 } else {
855 return true;
856 }
857 }
858
859
860 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
861 int klass_index = constants()->klass_ref_index_at(refinfo_index);
862 if (must_be_resolved) {
863 // Make sure klass is resolved in constantpool.
864 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
865 }
866 return is_klass_loaded_by_klass_index(klass_index);
867 }
868
869
870 void Method::set_native_function(address function, bool post_event_flag) {
871 assert(function != NULL, "use clear_native_function to unregister natives");
872 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
873 address* native_function = native_function_addr();
874
875 // We can see racers trying to place the same native function into place. Once
876 // is plenty.
877 address current = *native_function;
878 if (current == function) return;
879 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
880 function != NULL) {
881 // native_method_throw_unsatisfied_link_error_entry() should only
882 // be passed when post_event_flag is false.
883 assert(function !=
884 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
885 "post_event_flag mis-match");
886
887 // post the bind event, and possible change the bind function
888 JvmtiExport::post_native_method_bind(this, &function);
889 }
890 *native_function = function;
891 // This function can be called more than once. We must make sure that we always
892 // use the latest registered method -> check if a stub already has been generated.
893 // If so, we have to make it not_entrant.
894 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
895 if (nm != NULL) {
896 nm->make_not_entrant();
897 }
898 }
899
900
901 bool Method::has_native_function() const {
902 if (is_method_handle_intrinsic())
903 return false; // special-cased in SharedRuntime::generate_native_wrapper
904 address func = native_function();
905 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
906 }
907
908
909 void Method::clear_native_function() {
910 // Note: is_method_handle_intrinsic() is allowed here.
911 set_native_function(
912 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
913 !native_bind_event_is_interesting);
914 this->unlink_code();
915 }
916
917
918 void Method::set_signature_handler(address handler) {
919 address* signature_handler = signature_handler_addr();
920 *signature_handler = handler;
921 }
922
923
924 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
925 assert(reason != NULL, "must provide a reason");
926 if (PrintCompilation && report) {
927 ttyLocker ttyl;
928 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
929 if (comp_level == CompLevel_all) {
930 tty->print("all levels ");
931 } else {
932 tty->print("level %d ", comp_level);
933 }
934 this->print_short_name(tty);
935 int size = this->code_size();
936 if (size > 0) {
937 tty->print(" (%d bytes)", size);
938 }
939 if (reason != NULL) {
940 tty->print(" %s", reason);
941 }
942 tty->cr();
943 }
944 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
945 ttyLocker ttyl;
946 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
947 os::current_thread_id(), is_osr, comp_level);
948 if (reason != NULL) {
949 xtty->print(" reason=\'%s\'", reason);
950 }
951 xtty->method(this);
952 xtty->stamp();
953 xtty->end_elem();
954 }
955 }
956
957 bool Method::is_always_compilable() const {
958 // Generated adapters must be compiled
959 if (is_method_handle_intrinsic() && is_synthetic()) {
960 assert(!is_not_c1_compilable(), "sanity check");
961 assert(!is_not_c2_compilable(), "sanity check");
962 return true;
963 }
964
965 return false;
966 }
967
968 bool Method::is_not_compilable(int comp_level) const {
969 if (number_of_breakpoints() > 0)
970 return true;
971 if (is_always_compilable())
972 return false;
973 if (comp_level == CompLevel_any)
974 return is_not_c1_compilable() || is_not_c2_compilable();
975 if (is_c1_compile(comp_level))
976 return is_not_c1_compilable();
977 if (is_c2_compile(comp_level))
978 return is_not_c2_compilable();
979 return false;
980 }
981
982 // call this when compiler finds that this method is not compilable
983 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
984 if (is_always_compilable()) {
985 // Don't mark a method which should be always compilable
986 return;
987 }
988 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
989 if (comp_level == CompLevel_all) {
990 set_not_c1_compilable();
991 set_not_c2_compilable();
992 } else {
993 if (is_c1_compile(comp_level))
994 set_not_c1_compilable();
995 if (is_c2_compile(comp_level))
996 set_not_c2_compilable();
997 }
998 CompilationPolicy::policy()->disable_compilation(this);
999 assert(!CompilationPolicy::can_be_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1000 }
1001
1002 bool Method::is_not_osr_compilable(int comp_level) const {
1003 if (is_not_compilable(comp_level))
1004 return true;
1005 if (comp_level == CompLevel_any)
1006 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
1007 if (is_c1_compile(comp_level))
1008 return is_not_c1_osr_compilable();
1009 if (is_c2_compile(comp_level))
1010 return is_not_c2_osr_compilable();
1011 return false;
1012 }
1013
1014 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
1015 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
1016 if (comp_level == CompLevel_all) {
1017 set_not_c1_osr_compilable();
1018 set_not_c2_osr_compilable();
1019 } else {
1020 if (is_c1_compile(comp_level))
1021 set_not_c1_osr_compilable();
1022 if (is_c2_compile(comp_level))
1023 set_not_c2_osr_compilable();
1024 }
1025 CompilationPolicy::policy()->disable_compilation(this);
1026 assert(!CompilationPolicy::can_be_osr_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1027 }
1028
1029 // Revert to using the interpreter and clear out the nmethod
1030 void Method::clear_code() {
1031 // this may be NULL if c2i adapters have not been made yet
1032 // Only should happen at allocate time.
1033 if (adapter() == NULL) {
1034 _from_compiled_entry = NULL;
1035 } else {
1036 _from_compiled_entry = adapter()->get_c2i_entry();
1037 }
1038 OrderAccess::storestore();
1039 _from_interpreted_entry = _i2i_entry;
1040 OrderAccess::storestore();
1041 _code = NULL;
1042 }
1043
1044 void Method::unlink_code(CompiledMethod *compare) {
1045 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1046 // We need to check if either the _code or _from_compiled_code_entry_point
1047 // refer to this nmethod because there is a race in setting these two fields
1048 // in Method* as seen in bugid 4947125.
1049 // If the vep() points to the zombie nmethod, the memory for the nmethod
1050 // could be flushed and the compiler and vtable stubs could still call
1051 // through it.
1052 if (code() == compare ||
1053 from_compiled_entry() == compare->verified_entry_point()) {
1054 clear_code();
1055 }
1056 }
1057
1058 void Method::unlink_code() {
1059 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1060 clear_code();
1061 }
1062
1063 #if INCLUDE_CDS
1064 // Called by class data sharing to remove any entry points (which are not shared)
1065 void Method::unlink_method() {
1066 _code = NULL;
1067
1068 Arguments::assert_is_dumping_archive();
1069 // Set the values to what they should be at run time. Note that
1070 // this Method can no longer be executed during dump time.
1071 _i2i_entry = Interpreter::entry_for_cds_method(methodHandle(Thread::current(), this));
1072 _from_interpreted_entry = _i2i_entry;
1073
1074 if (DynamicDumpSharedSpaces) {
1075 assert(_from_compiled_entry != NULL, "sanity");
1076 } else {
1077 // TODO: Simplify the adapter trampoline allocation for static archiving.
1078 // Remove the use of CDSAdapterHandlerEntry.
1079 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
1080 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
1081 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
1082 assert(*((int*)_from_compiled_entry) == 0,
1083 "must be NULL during dump time, to be initialized at run time");
1084 }
1085
1086 if (is_native()) {
1087 *native_function_addr() = NULL;
1088 set_signature_handler(NULL);
1089 }
1090 NOT_PRODUCT(set_compiled_invocation_count(0);)
1091
1092 set_method_data(NULL);
1093 clear_method_counters();
1094 }
1095 #endif
1096
1097 /****************************************************************************
1098 // The following illustrates how the entries work for CDS shared Methods:
1099 //
1100 // Our goal is to delay writing into a shared Method until it's compiled.
1101 // Hence, we want to determine the initial values for _i2i_entry,
1102 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
1103 //
1104 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
1105 // They also have similar signatures so that they will share the same
1106 // AdapterHandlerEntry.
1107 //
1108 // _adapter_trampoline points to a fixed location in the RW section of
1109 // the CDS archive. This location initially contains a NULL pointer. When the
1110 // first of method A or B is linked, an AdapterHandlerEntry is allocated
1111 // dynamically, and its c2i/i2c entries are generated.
1112 //
1113 // _i2i_entry and _from_interpreted_entry initially points to the same
1114 // (fixed) location in the CODE section of the CDS archive. This contains
1115 // an unconditional branch to the actual entry for "zero_locals", which is
1116 // generated at run time and may be on an arbitrary address. Thus, the
1117 // unconditional branch is also generated at run time to jump to the correct
1118 // address.
1119 //
1120 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1121 // section. This address has enough space for an unconditional branch
1122 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1123 // initialized, and the address for the actual c2i_entry is known, we emit a
1124 // branch instruction here to branch to the actual c2i_entry.
1125 //
1126 // The effect of the extra branch on the i2i and c2i entries is negligible.
1127 //
1128 // The reason for putting _adapter_trampoline in RO is many shared Methods
1129 // share the same AdapterHandlerEntry, so we can save space in the RW section
1130 // by having the extra indirection.
1131
1132
1133 [Method A: RW]
1134 _constMethod ----> [ConstMethod: RO]
1135 _adapter_trampoline -----------+
1136 |
1137 _i2i_entry (same value as method B) |
1138 _from_interpreted_entry (same value as method B) |
1139 _from_compiled_entry (same value as method B) |
1140 |
1141 |
1142 [Method B: RW] +--------+
1143 _constMethod ----> [ConstMethod: RO] |
1144 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1145 |
1146 +-------------------------------+
1147 |
1148 +----> [AdapterHandlerEntry] (allocated at run time)
1149 _fingerprint
1150 _c2i_entry ---------------------------------+->[c2i entry..]
1151 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1152 _from_interpreted_entry | _c2i_unverified_entry | |
1153 | | _c2i_no_clinit_check_entry| |
1154 | | (_cds_entry_table: CODE) | |
1155 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1156 | | (allocated at run time) | |
1157 | | ... [asm code ...] | |
1158 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1159 | | |
1160 | | |
1161 +-[compiled]-------------------------------------------------------------------+ |
1162 |
1163 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1164 [jmp c2i_entry] ------------------------------------------------------+
1165
1166 ***/
1167
1168 // Called when the method_holder is getting linked. Setup entrypoints so the method
1169 // is ready to be called from interpreter, compiler, and vtables.
1170 void Method::link_method(const methodHandle& h_method, TRAPS) {
1171 // If the code cache is full, we may reenter this function for the
1172 // leftover methods that weren't linked.
1173 if (is_shared()) {
1174 address entry = Interpreter::entry_for_cds_method(h_method);
1175 assert(entry != NULL && entry == _i2i_entry,
1176 "should be correctly set during dump time");
1177 if (adapter() != NULL) {
1178 return;
1179 }
1180 assert(entry == _from_interpreted_entry,
1181 "should be correctly set during dump time");
1182 } else if (_i2i_entry != NULL) {
1183 return;
1184 }
1185 assert( _code == NULL, "nothing compiled yet" );
1186
1187 // Setup interpreter entrypoint
1188 assert(this == h_method(), "wrong h_method()" );
1189
1190 if (!is_shared()) {
1191 assert(adapter() == NULL, "init'd to NULL");
1192 address entry = Interpreter::entry_for_method(h_method);
1193 assert(entry != NULL, "interpreter entry must be non-null");
1194 // Sets both _i2i_entry and _from_interpreted_entry
1195 set_interpreter_entry(entry);
1196 }
1197
1198 // Don't overwrite already registered native entries.
1199 if (is_native() && !has_native_function()) {
1200 set_native_function(
1201 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1202 !native_bind_event_is_interesting);
1203 }
1204
1205 // Setup compiler entrypoint. This is made eagerly, so we do not need
1206 // special handling of vtables. An alternative is to make adapters more
1207 // lazily by calling make_adapter() from from_compiled_entry() for the
1208 // normal calls. For vtable calls life gets more complicated. When a
1209 // call-site goes mega-morphic we need adapters in all methods which can be
1210 // called from the vtable. We need adapters on such methods that get loaded
1211 // later. Ditto for mega-morphic itable calls. If this proves to be a
1212 // problem we'll make these lazily later.
1213 (void) make_adapters(h_method, CHECK);
1214
1215 // ONLY USE the h_method now as make_adapter may have blocked
1216
1217 }
1218
1219 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1220 // Adapters for compiled code are made eagerly here. They are fairly
1221 // small (generally < 100 bytes) and quick to make (and cached and shared)
1222 // so making them eagerly shouldn't be too expensive.
1223 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1224 if (adapter == NULL ) {
1225 if (!is_init_completed()) {
1226 // Don't throw exceptions during VM initialization because java.lang.* classes
1227 // might not have been initialized, causing problems when constructing the
1228 // Java exception object.
1229 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1230 } else {
1231 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1232 }
1233 }
1234
1235 if (mh->is_shared()) {
1236 assert(mh->adapter() == adapter, "must be");
1237 assert(mh->_from_compiled_entry != NULL, "must be");
1238 } else {
1239 mh->set_adapter_entry(adapter);
1240 mh->_from_compiled_entry = adapter->get_c2i_entry();
1241 }
1242 return adapter->get_c2i_entry();
1243 }
1244
1245 void Method::restore_unshareable_info(TRAPS) {
1246 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1247
1248 // Since restore_unshareable_info can be called more than once for a method, don't
1249 // redo any work.
1250 if (adapter() == NULL) {
1251 methodHandle mh(THREAD, this);
1252 link_method(mh, CHECK);
1253 }
1254 }
1255
1256 address Method::from_compiled_entry_no_trampoline() const {
1257 CompiledMethod *code = Atomic::load_acquire(&_code);
1258 if (code) {
1259 return code->verified_entry_point();
1260 } else {
1261 return adapter()->get_c2i_entry();
1262 }
1263 }
1264
1265 // The verified_code_entry() must be called when a invoke is resolved
1266 // on this method.
1267
1268 // It returns the compiled code entry point, after asserting not null.
1269 // This function is called after potential safepoints so that nmethod
1270 // or adapter that it points to is still live and valid.
1271 // This function must not hit a safepoint!
1272 address Method::verified_code_entry() {
1273 debug_only(NoSafepointVerifier nsv;)
1274 assert(_from_compiled_entry != NULL, "must be set");
1275 return _from_compiled_entry;
1276 }
1277
1278 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1279 // (could be racing a deopt).
1280 // Not inline to avoid circular ref.
1281 bool Method::check_code() const {
1282 // cached in a register or local. There's a race on the value of the field.
1283 CompiledMethod *code = Atomic::load_acquire(&_code);
1284 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1285 }
1286
1287 // Install compiled code. Instantly it can execute.
1288 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1289 assert_lock_strong(CompiledMethod_lock);
1290 assert( code, "use clear_code to remove code" );
1291 assert( mh->check_code(), "" );
1292
1293 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1294
1295 // These writes must happen in this order, because the interpreter will
1296 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1297 // which jumps to _from_compiled_entry.
1298 mh->_code = code; // Assign before allowing compiled code to exec
1299
1300 int comp_level = code->comp_level();
1301 // In theory there could be a race here. In practice it is unlikely
1302 // and not worth worrying about.
1303 if (comp_level > mh->highest_comp_level()) {
1304 mh->set_highest_comp_level(comp_level);
1305 }
1306
1307 OrderAccess::storestore();
1308 mh->_from_compiled_entry = code->verified_entry_point();
1309 OrderAccess::storestore();
1310 // Instantly compiled code can execute.
1311 if (!mh->is_method_handle_intrinsic())
1312 mh->_from_interpreted_entry = mh->get_i2c_entry();
1313 }
1314
1315
1316 bool Method::is_overridden_in(Klass* k) const {
1317 InstanceKlass* ik = InstanceKlass::cast(k);
1318
1319 if (ik->is_interface()) return false;
1320
1321 // If method is an interface, we skip it - except if it
1322 // is a miranda method
1323 if (method_holder()->is_interface()) {
1324 // Check that method is not a miranda method
1325 if (ik->lookup_method(name(), signature()) == NULL) {
1326 // No implementation exist - so miranda method
1327 return false;
1328 }
1329 return true;
1330 }
1331
1332 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1333 if (!has_vtable_index()) {
1334 return false;
1335 } else {
1336 Method* vt_m = ik->method_at_vtable(vtable_index());
1337 return vt_m != this;
1338 }
1339 }
1340
1341
1342 // give advice about whether this Method* should be cached or not
1343 bool Method::should_not_be_cached() const {
1344 if (is_old()) {
1345 // This method has been redefined. It is either EMCP or obsolete
1346 // and we don't want to cache it because that would pin the method
1347 // down and prevent it from being collectible if and when it
1348 // finishes executing.
1349 return true;
1350 }
1351
1352 // caching this method should be just fine
1353 return false;
1354 }
1355
1356
1357 /**
1358 * Returns true if this is one of the specially treated methods for
1359 * security related stack walks (like Reflection.getCallerClass).
1360 */
1361 bool Method::is_ignored_by_security_stack_walk() const {
1362 if (intrinsic_id() == vmIntrinsics::_invoke) {
1363 // This is Method.invoke() -- ignore it
1364 return true;
1365 }
1366 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1367 // This is an auxilary frame -- ignore it
1368 return true;
1369 }
1370 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1371 // This is an internal adapter frame for method handles -- ignore it
1372 return true;
1373 }
1374 return false;
1375 }
1376
1377
1378 // Constant pool structure for invoke methods:
1379 enum {
1380 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1381 _imcp_invoke_signature, // utf8: (variable Symbol*)
1382 _imcp_limit
1383 };
1384
1385 // Test if this method is an MH adapter frame generated by Java code.
1386 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1387 bool Method::is_compiled_lambda_form() const {
1388 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1389 }
1390
1391 // Test if this method is an internal MH primitive method.
1392 bool Method::is_method_handle_intrinsic() const {
1393 vmIntrinsics::ID iid = intrinsic_id();
1394 return (MethodHandles::is_signature_polymorphic(iid) &&
1395 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1396 }
1397
1398 bool Method::has_member_arg() const {
1399 vmIntrinsics::ID iid = intrinsic_id();
1400 return (MethodHandles::is_signature_polymorphic(iid) &&
1401 MethodHandles::has_member_arg(iid));
1402 }
1403
1404 // Make an instance of a signature-polymorphic internal MH primitive.
1405 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1406 Symbol* signature,
1407 TRAPS) {
1408 ResourceMark rm(THREAD);
1409 methodHandle empty;
1410
1411 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1412 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1413 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1414 if (TraceMethodHandles) {
1415 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1416 }
1417
1418 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1419 name->increment_refcount();
1420 signature->increment_refcount();
1421
1422 int cp_length = _imcp_limit;
1423 ClassLoaderData* loader_data = holder->class_loader_data();
1424 constantPoolHandle cp;
1425 {
1426 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1427 cp = constantPoolHandle(THREAD, cp_oop);
1428 }
1429 cp->set_pool_holder(holder);
1430 cp->symbol_at_put(_imcp_invoke_name, name);
1431 cp->symbol_at_put(_imcp_invoke_signature, signature);
1432 cp->set_has_preresolution();
1433
1434 // decide on access bits: public or not?
1435 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1436 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1437 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1438 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1439
1440 methodHandle m;
1441 {
1442 InlineTableSizes sizes;
1443 Method* m_oop = Method::allocate(loader_data, 0,
1444 accessFlags_from(flags_bits), &sizes,
1445 ConstMethod::NORMAL, CHECK_(empty));
1446 m = methodHandle(THREAD, m_oop);
1447 }
1448 m->set_constants(cp());
1449 m->set_name_index(_imcp_invoke_name);
1450 m->set_signature_index(_imcp_invoke_signature);
1451 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1452 assert(m->signature() == signature, "");
1453 m->compute_from_signature(signature);
1454 m->init_intrinsic_id();
1455 assert(m->is_method_handle_intrinsic(), "");
1456 #ifdef ASSERT
1457 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1458 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1459 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1460 #endif //ASSERT
1461
1462 // Finally, set up its entry points.
1463 assert(m->can_be_statically_bound(), "");
1464 m->set_vtable_index(Method::nonvirtual_vtable_index);
1465 m->link_method(m, CHECK_(empty));
1466
1467 if (TraceMethodHandles && (Verbose || WizardMode)) {
1468 ttyLocker ttyl;
1469 m->print_on(tty);
1470 }
1471
1472 return m;
1473 }
1474
1475 Klass* Method::check_non_bcp_klass(Klass* klass) {
1476 if (klass != NULL && klass->class_loader() != NULL) {
1477 if (klass->is_objArray_klass())
1478 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1479 return klass;
1480 }
1481 return NULL;
1482 }
1483
1484
1485 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1486 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1487 // Code below does not work for native methods - they should never get rewritten anyway
1488 assert(!m->is_native(), "cannot rewrite native methods");
1489 // Allocate new Method*
1490 AccessFlags flags = m->access_flags();
1491
1492 ConstMethod* cm = m->constMethod();
1493 int checked_exceptions_len = cm->checked_exceptions_length();
1494 int localvariable_len = cm->localvariable_table_length();
1495 int exception_table_len = cm->exception_table_length();
1496 int method_parameters_len = cm->method_parameters_length();
1497 int method_annotations_len = cm->method_annotations_length();
1498 int parameter_annotations_len = cm->parameter_annotations_length();
1499 int type_annotations_len = cm->type_annotations_length();
1500 int default_annotations_len = cm->default_annotations_length();
1501
1502 InlineTableSizes sizes(
1503 localvariable_len,
1504 new_compressed_linenumber_size,
1505 exception_table_len,
1506 checked_exceptions_len,
1507 method_parameters_len,
1508 cm->generic_signature_index(),
1509 method_annotations_len,
1510 parameter_annotations_len,
1511 type_annotations_len,
1512 default_annotations_len,
1513 0);
1514
1515 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1516 Method* newm_oop = Method::allocate(loader_data,
1517 new_code_length,
1518 flags,
1519 &sizes,
1520 m->method_type(),
1521 CHECK_(methodHandle()));
1522 methodHandle newm (THREAD, newm_oop);
1523
1524 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1525 ConstMethod* newcm = newm->constMethod();
1526 int new_const_method_size = newm->constMethod()->size();
1527
1528 // This works because the source and target are both Methods. Some compilers
1529 // (e.g., clang) complain that the target vtable pointer will be stomped,
1530 // so cast away newm()'s and m()'s Methodness.
1531 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1532
1533 // Create shallow copy of ConstMethod.
1534 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1535
1536 // Reset correct method/const method, method size, and parameter info
1537 newm->set_constMethod(newcm);
1538 newm->constMethod()->set_code_size(new_code_length);
1539 newm->constMethod()->set_constMethod_size(new_const_method_size);
1540 assert(newm->code_size() == new_code_length, "check");
1541 assert(newm->method_parameters_length() == method_parameters_len, "check");
1542 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1543 assert(newm->exception_table_length() == exception_table_len, "check");
1544 assert(newm->localvariable_table_length() == localvariable_len, "check");
1545 // Copy new byte codes
1546 memcpy(newm->code_base(), new_code, new_code_length);
1547 // Copy line number table
1548 if (new_compressed_linenumber_size > 0) {
1549 memcpy(newm->compressed_linenumber_table(),
1550 new_compressed_linenumber_table,
1551 new_compressed_linenumber_size);
1552 }
1553 // Copy method_parameters
1554 if (method_parameters_len > 0) {
1555 memcpy(newm->method_parameters_start(),
1556 m->method_parameters_start(),
1557 method_parameters_len * sizeof(MethodParametersElement));
1558 }
1559 // Copy checked_exceptions
1560 if (checked_exceptions_len > 0) {
1561 memcpy(newm->checked_exceptions_start(),
1562 m->checked_exceptions_start(),
1563 checked_exceptions_len * sizeof(CheckedExceptionElement));
1564 }
1565 // Copy exception table
1566 if (exception_table_len > 0) {
1567 memcpy(newm->exception_table_start(),
1568 m->exception_table_start(),
1569 exception_table_len * sizeof(ExceptionTableElement));
1570 }
1571 // Copy local variable number table
1572 if (localvariable_len > 0) {
1573 memcpy(newm->localvariable_table_start(),
1574 m->localvariable_table_start(),
1575 localvariable_len * sizeof(LocalVariableTableElement));
1576 }
1577 // Copy stackmap table
1578 if (m->has_stackmap_table()) {
1579 int code_attribute_length = m->stackmap_data()->length();
1580 Array<u1>* stackmap_data =
1581 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_(methodHandle()));
1582 memcpy((void*)stackmap_data->adr_at(0),
1583 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1584 newm->set_stackmap_data(stackmap_data);
1585 }
1586
1587 // copy annotations over to new method
1588 newcm->copy_annotations_from(loader_data, cm, CHECK_(methodHandle()));
1589 return newm;
1590 }
1591
1592 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1593 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1594 // because we are not loading from core libraries
1595 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1596 // which does not use the class default class loader so we check for its loader here
1597 const InstanceKlass* ik = InstanceKlass::cast(holder);
1598 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1599 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1600 }
1601
1602 // see if the klass name is well-known:
1603 Symbol* klass_name = ik->name();
1604 return vmSymbols::find_sid(klass_name);
1605 }
1606
1607 void Method::init_intrinsic_id() {
1608 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1609 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1610 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1611 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1612
1613 // the klass name is well-known:
1614 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1615 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1616
1617 // ditto for method and signature:
1618 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1619 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1620 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1621 && name_id == vmSymbols::NO_SID) {
1622 return;
1623 }
1624 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1625 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1626 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1627 && sig_id == vmSymbols::NO_SID) {
1628 return;
1629 }
1630 jshort flags = access_flags().as_short();
1631
1632 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1633 if (id != vmIntrinsics::_none) {
1634 set_intrinsic_id(id);
1635 if (id == vmIntrinsics::_Class_cast) {
1636 // Even if the intrinsic is rejected, we want to inline this simple method.
1637 set_force_inline(true);
1638 }
1639 return;
1640 }
1641
1642 // A few slightly irregular cases:
1643 switch (klass_id) {
1644 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1645 // Second chance: check in regular Math.
1646 switch (name_id) {
1647 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1648 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1649 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1650 // pretend it is the corresponding method in the non-strict class:
1651 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1652 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1653 break;
1654 default:
1655 break;
1656 }
1657 break;
1658
1659 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1660 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1661 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1662 if (!is_native()) break;
1663 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1664 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1665 id = vmIntrinsics::_none;
1666 break;
1667
1668 default:
1669 break;
1670 }
1671
1672 if (id != vmIntrinsics::_none) {
1673 // Set up its iid. It is an alias method.
1674 set_intrinsic_id(id);
1675 return;
1676 }
1677 }
1678
1679 // These two methods are static since a GC may move the Method
1680 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1681 if (!THREAD->can_call_java()) {
1682 // There is nothing useful this routine can do from within the Compile thread.
1683 // Hopefully, the signature contains only well-known classes.
1684 // We could scan for this and return true/false, but the caller won't care.
1685 return false;
1686 }
1687 bool sig_is_loaded = true;
1688 Handle class_loader(THREAD, m->method_holder()->class_loader());
1689 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1690 ResourceMark rm(THREAD);
1691 Symbol* signature = m->signature();
1692 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1693 if (ss.is_reference()) {
1694 Symbol* sym = ss.as_symbol();
1695 Symbol* name = sym;
1696 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1697 protection_domain, THREAD);
1698 // We are loading classes eagerly. If a ClassNotFoundException or
1699 // a LinkageError was generated, be sure to ignore it.
1700 if (HAS_PENDING_EXCEPTION) {
1701 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1702 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1703 CLEAR_PENDING_EXCEPTION;
1704 } else {
1705 return false;
1706 }
1707 }
1708 if( klass == NULL) { sig_is_loaded = false; }
1709 }
1710 }
1711 return sig_is_loaded;
1712 }
1713
1714 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1715 Handle class_loader(THREAD, m->method_holder()->class_loader());
1716 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1717 ResourceMark rm(THREAD);
1718 Symbol* signature = m->signature();
1719 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1720 if (ss.type() == T_OBJECT) {
1721 Symbol* name = ss.as_symbol();
1722 if (name == NULL) return true;
1723 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1724 if (klass == NULL) return true;
1725 }
1726 }
1727 return false;
1728 }
1729
1730 // Exposed so field engineers can debug VM
1731 void Method::print_short_name(outputStream* st) {
1732 ResourceMark rm;
1733 #ifdef PRODUCT
1734 st->print(" %s::", method_holder()->external_name());
1735 #else
1736 st->print(" %s::", method_holder()->internal_name());
1737 #endif
1738 name()->print_symbol_on(st);
1739 if (WizardMode) signature()->print_symbol_on(st);
1740 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1741 MethodHandles::print_as_basic_type_signature_on(st, signature());
1742 }
1743
1744 // Comparer for sorting an object array containing
1745 // Method*s.
1746 static int method_comparator(Method* a, Method* b) {
1747 return a->name()->fast_compare(b->name());
1748 }
1749
1750 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1751 // default_methods also uses this without the ordering for fast find_method
1752 void Method::sort_methods(Array<Method*>* methods, bool set_idnums, method_comparator_func func) {
1753 int length = methods->length();
1754 if (length > 1) {
1755 if (func == NULL) {
1756 func = method_comparator;
1757 }
1758 {
1759 NoSafepointVerifier nsv;
1760 QuickSort::sort(methods->data(), length, func, /*idempotent=*/false);
1761 }
1762 // Reset method ordering
1763 if (set_idnums) {
1764 for (int i = 0; i < length; i++) {
1765 Method* m = methods->at(i);
1766 m->set_method_idnum(i);
1767 m->set_orig_method_idnum(i);
1768 }
1769 }
1770 }
1771 }
1772
1773 //-----------------------------------------------------------------------------------
1774 // Non-product code unless JVM/TI needs it
1775
1776 #if !defined(PRODUCT) || INCLUDE_JVMTI
1777 class SignatureTypePrinter : public SignatureTypeNames {
1778 private:
1779 outputStream* _st;
1780 bool _use_separator;
1781
1782 void type_name(const char* name) {
1783 if (_use_separator) _st->print(", ");
1784 _st->print("%s", name);
1785 _use_separator = true;
1786 }
1787
1788 public:
1789 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1790 _st = st;
1791 _use_separator = false;
1792 }
1793
1794 void print_parameters() { _use_separator = false; do_parameters_on(this); }
1795 void print_returntype() { _use_separator = false; do_type(return_type()); }
1796 };
1797
1798
1799 void Method::print_name(outputStream* st) {
1800 Thread *thread = Thread::current();
1801 ResourceMark rm(thread);
1802 st->print("%s ", is_static() ? "static" : "virtual");
1803 if (WizardMode) {
1804 st->print("%s.", method_holder()->internal_name());
1805 name()->print_symbol_on(st);
1806 signature()->print_symbol_on(st);
1807 } else {
1808 SignatureTypePrinter sig(signature(), st);
1809 sig.print_returntype();
1810 st->print(" %s.", method_holder()->internal_name());
1811 name()->print_symbol_on(st);
1812 st->print("(");
1813 sig.print_parameters();
1814 st->print(")");
1815 }
1816 }
1817 #endif // !PRODUCT || INCLUDE_JVMTI
1818
1819
1820 void Method::print_codes_on(outputStream* st) const {
1821 print_codes_on(0, code_size(), st);
1822 }
1823
1824 void Method::print_codes_on(int from, int to, outputStream* st) const {
1825 Thread *thread = Thread::current();
1826 ResourceMark rm(thread);
1827 methodHandle mh (thread, (Method*)this);
1828 BytecodeStream s(mh);
1829 s.set_interval(from, to);
1830 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1831 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1832 }
1833
1834 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1835 _bci = 0;
1836 _line = 0;
1837 };
1838
1839 bool CompressedLineNumberReadStream::read_pair() {
1840 jubyte next = read_byte();
1841 // Check for terminator
1842 if (next == 0) return false;
1843 if (next == 0xFF) {
1844 // Escape character, regular compression used
1845 _bci += read_signed_int();
1846 _line += read_signed_int();
1847 } else {
1848 // Single byte compression used
1849 _bci += next >> 3;
1850 _line += next & 0x7;
1851 }
1852 return true;
1853 }
1854
1855 #if INCLUDE_JVMTI
1856
1857 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1858 BreakpointInfo* bp = method_holder()->breakpoints();
1859 for (; bp != NULL; bp = bp->next()) {
1860 if (bp->match(this, bci)) {
1861 return bp->orig_bytecode();
1862 }
1863 }
1864 {
1865 ResourceMark rm;
1866 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1867 }
1868 return Bytecodes::_shouldnotreachhere;
1869 }
1870
1871 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1872 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1873 BreakpointInfo* bp = method_holder()->breakpoints();
1874 for (; bp != NULL; bp = bp->next()) {
1875 if (bp->match(this, bci)) {
1876 bp->set_orig_bytecode(code);
1877 // and continue, in case there is more than one
1878 }
1879 }
1880 }
1881
1882 void Method::set_breakpoint(int bci) {
1883 InstanceKlass* ik = method_holder();
1884 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1885 bp->set_next(ik->breakpoints());
1886 ik->set_breakpoints(bp);
1887 // do this last:
1888 bp->set(this);
1889 }
1890
1891 static void clear_matches(Method* m, int bci) {
1892 InstanceKlass* ik = m->method_holder();
1893 BreakpointInfo* prev_bp = NULL;
1894 BreakpointInfo* next_bp;
1895 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1896 next_bp = bp->next();
1897 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1898 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1899 // do this first:
1900 bp->clear(m);
1901 // unhook it
1902 if (prev_bp != NULL)
1903 prev_bp->set_next(next_bp);
1904 else
1905 ik->set_breakpoints(next_bp);
1906 delete bp;
1907 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1908 // at same location. So we have multiple matching (method_index and bci)
1909 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1910 // breakpoint for clear_breakpoint request and keep all other method versions
1911 // BreakpointInfo for future clear_breakpoint request.
1912 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1913 // which is being called when class is unloaded. We delete all the Breakpoint
1914 // information for all versions of method. We may not correctly restore the original
1915 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1916 // so these methods won't be used anymore.
1917 if (bci >= 0) {
1918 break;
1919 }
1920 } else {
1921 // This one is a keeper.
1922 prev_bp = bp;
1923 }
1924 }
1925 }
1926
1927 void Method::clear_breakpoint(int bci) {
1928 assert(bci >= 0, "");
1929 clear_matches(this, bci);
1930 }
1931
1932 void Method::clear_all_breakpoints() {
1933 clear_matches(this, -1);
1934 }
1935
1936 #endif // INCLUDE_JVMTI
1937
1938 int Method::invocation_count() {
1939 MethodCounters *mcs = method_counters();
1940 if (TieredCompilation) {
1941 MethodData* const mdo = method_data();
1942 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1943 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1944 return InvocationCounter::count_limit;
1945 } else {
1946 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1947 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1948 }
1949 } else {
1950 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1951 }
1952 }
1953
1954 int Method::backedge_count() {
1955 MethodCounters *mcs = method_counters();
1956 if (TieredCompilation) {
1957 MethodData* const mdo = method_data();
1958 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1959 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1960 return InvocationCounter::count_limit;
1961 } else {
1962 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1963 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1964 }
1965 } else {
1966 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1967 }
1968 }
1969
1970 int Method::highest_comp_level() const {
1971 const MethodCounters* mcs = method_counters();
1972 if (mcs != NULL) {
1973 return mcs->highest_comp_level();
1974 } else {
1975 return CompLevel_none;
1976 }
1977 }
1978
1979 int Method::highest_osr_comp_level() const {
1980 const MethodCounters* mcs = method_counters();
1981 if (mcs != NULL) {
1982 return mcs->highest_osr_comp_level();
1983 } else {
1984 return CompLevel_none;
1985 }
1986 }
1987
1988 void Method::set_highest_comp_level(int level) {
1989 MethodCounters* mcs = method_counters();
1990 if (mcs != NULL) {
1991 mcs->set_highest_comp_level(level);
1992 }
1993 }
1994
1995 void Method::set_highest_osr_comp_level(int level) {
1996 MethodCounters* mcs = method_counters();
1997 if (mcs != NULL) {
1998 mcs->set_highest_osr_comp_level(level);
1999 }
2000 }
2001
2002 #if INCLUDE_JVMTI
2003
2004 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
2005 _bci = bci;
2006 _name_index = m->name_index();
2007 _signature_index = m->signature_index();
2008 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
2009 if (_orig_bytecode == Bytecodes::_breakpoint)
2010 _orig_bytecode = m->orig_bytecode_at(_bci);
2011 _next = NULL;
2012 }
2013
2014 void BreakpointInfo::set(Method* method) {
2015 #ifdef ASSERT
2016 {
2017 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
2018 if (code == Bytecodes::_breakpoint)
2019 code = method->orig_bytecode_at(_bci);
2020 assert(orig_bytecode() == code, "original bytecode must be the same");
2021 }
2022 #endif
2023 Thread *thread = Thread::current();
2024 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
2025 method->incr_number_of_breakpoints(thread);
2026 {
2027 // Deoptimize all dependents on this method
2028 HandleMark hm(thread);
2029 methodHandle mh(thread, method);
2030 CodeCache::flush_dependents_on_method(mh);
2031 }
2032 }
2033
2034 void BreakpointInfo::clear(Method* method) {
2035 *method->bcp_from(_bci) = orig_bytecode();
2036 assert(method->number_of_breakpoints() > 0, "must not go negative");
2037 method->decr_number_of_breakpoints(Thread::current());
2038 }
2039
2040 #endif // INCLUDE_JVMTI
2041
2042 // jmethodID handling
2043
2044 // This is a block allocating object, sort of like JNIHandleBlock, only a
2045 // lot simpler.
2046 // It's allocated on the CHeap because once we allocate a jmethodID, we can
2047 // never get rid of it.
2048
2049 static const int min_block_size = 8;
2050
2051 class JNIMethodBlockNode : public CHeapObj<mtClass> {
2052 friend class JNIMethodBlock;
2053 Method** _methods;
2054 int _number_of_methods;
2055 int _top;
2056 JNIMethodBlockNode* _next;
2057
2058 public:
2059
2060 JNIMethodBlockNode(int num_methods = min_block_size);
2061
2062 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
2063
2064 void ensure_methods(int num_addl_methods) {
2065 if (_top < _number_of_methods) {
2066 num_addl_methods -= _number_of_methods - _top;
2067 if (num_addl_methods <= 0) {
2068 return;
2069 }
2070 }
2071 if (_next == NULL) {
2072 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
2073 } else {
2074 _next->ensure_methods(num_addl_methods);
2075 }
2076 }
2077 };
2078
2079 class JNIMethodBlock : public CHeapObj<mtClass> {
2080 JNIMethodBlockNode _head;
2081 JNIMethodBlockNode *_last_free;
2082 public:
2083 static Method* const _free_method;
2084
2085 JNIMethodBlock(int initial_capacity = min_block_size)
2086 : _head(initial_capacity), _last_free(&_head) {}
2087
2088 void ensure_methods(int num_addl_methods) {
2089 _last_free->ensure_methods(num_addl_methods);
2090 }
2091
2092 Method** add_method(Method* m) {
2093 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2094 if (b->_top < b->_number_of_methods) {
2095 // top points to the next free entry.
2096 int i = b->_top;
2097 b->_methods[i] = m;
2098 b->_top++;
2099 _last_free = b;
2100 return &(b->_methods[i]);
2101 } else if (b->_top == b->_number_of_methods) {
2102 // if the next free entry ran off the block see if there's a free entry
2103 for (int i = 0; i < b->_number_of_methods; i++) {
2104 if (b->_methods[i] == _free_method) {
2105 b->_methods[i] = m;
2106 _last_free = b;
2107 return &(b->_methods[i]);
2108 }
2109 }
2110 // Only check each block once for frees. They're very unlikely.
2111 // Increment top past the end of the block.
2112 b->_top++;
2113 }
2114 // need to allocate a next block.
2115 if (b->_next == NULL) {
2116 b->_next = _last_free = new JNIMethodBlockNode();
2117 }
2118 }
2119 guarantee(false, "Should always allocate a free block");
2120 return NULL;
2121 }
2122
2123 bool contains(Method** m) {
2124 if (m == NULL) return false;
2125 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2126 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2127 // This is a bit of extra checking, for two reasons. One is
2128 // that contains() deals with pointers that are passed in by
2129 // JNI code, so making sure that the pointer is aligned
2130 // correctly is valuable. The other is that <= and > are
2131 // technically not defined on pointers, so the if guard can
2132 // pass spuriously; no modern compiler is likely to make that
2133 // a problem, though (and if one did, the guard could also
2134 // fail spuriously, which would be bad).
2135 ptrdiff_t idx = m - b->_methods;
2136 if (b->_methods + idx == m) {
2137 return true;
2138 }
2139 }
2140 }
2141 return false; // not found
2142 }
2143
2144 // Doesn't really destroy it, just marks it as free so it can be reused.
2145 void destroy_method(Method** m) {
2146 #ifdef ASSERT
2147 assert(contains(m), "should be a methodID");
2148 #endif // ASSERT
2149 *m = _free_method;
2150 }
2151
2152 // During class unloading the methods are cleared, which is different
2153 // than freed.
2154 void clear_all_methods() {
2155 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2156 for (int i = 0; i< b->_number_of_methods; i++) {
2157 b->_methods[i] = NULL;
2158 }
2159 }
2160 }
2161 #ifndef PRODUCT
2162 int count_methods() {
2163 // count all allocated methods
2164 int count = 0;
2165 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2166 for (int i = 0; i< b->_number_of_methods; i++) {
2167 if (b->_methods[i] != _free_method) count++;
2168 }
2169 }
2170 return count;
2171 }
2172 #endif // PRODUCT
2173 };
2174
2175 // Something that can't be mistaken for an address or a markWord
2176 Method* const JNIMethodBlock::_free_method = (Method*)55;
2177
2178 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2179 _number_of_methods = MAX2(num_methods, min_block_size);
2180 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2181 for (int i = 0; i < _number_of_methods; i++) {
2182 _methods[i] = JNIMethodBlock::_free_method;
2183 }
2184 }
2185
2186 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2187 ClassLoaderData* cld = loader_data;
2188 if (!SafepointSynchronize::is_at_safepoint()) {
2189 // Have to add jmethod_ids() to class loader data thread-safely.
2190 // Also have to add the method to the list safely, which the cld lock
2191 // protects as well.
2192 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2193 if (cld->jmethod_ids() == NULL) {
2194 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2195 } else {
2196 cld->jmethod_ids()->ensure_methods(capacity);
2197 }
2198 } else {
2199 // At safepoint, we are single threaded and can set this.
2200 if (cld->jmethod_ids() == NULL) {
2201 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2202 } else {
2203 cld->jmethod_ids()->ensure_methods(capacity);
2204 }
2205 }
2206 }
2207
2208 // Add a method id to the jmethod_ids
2209 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2210 ClassLoaderData* cld = loader_data;
2211
2212 if (!SafepointSynchronize::is_at_safepoint()) {
2213 // Have to add jmethod_ids() to class loader data thread-safely.
2214 // Also have to add the method to the list safely, which the cld lock
2215 // protects as well.
2216 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2217 if (cld->jmethod_ids() == NULL) {
2218 cld->set_jmethod_ids(new JNIMethodBlock());
2219 }
2220 // jmethodID is a pointer to Method*
2221 return (jmethodID)cld->jmethod_ids()->add_method(m);
2222 } else {
2223 // At safepoint, we are single threaded and can set this.
2224 if (cld->jmethod_ids() == NULL) {
2225 cld->set_jmethod_ids(new JNIMethodBlock());
2226 }
2227 // jmethodID is a pointer to Method*
2228 return (jmethodID)cld->jmethod_ids()->add_method(m);
2229 }
2230 }
2231
2232 jmethodID Method::jmethod_id() {
2233 methodHandle mh(Thread::current(), this);
2234 return method_holder()->get_jmethod_id(mh);
2235 }
2236
2237 // Mark a jmethodID as free. This is called when there is a data race in
2238 // InstanceKlass while creating the jmethodID cache.
2239 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2240 ClassLoaderData* cld = loader_data;
2241 Method** ptr = (Method**)m;
2242 assert(cld->jmethod_ids() != NULL, "should have method handles");
2243 cld->jmethod_ids()->destroy_method(ptr);
2244 }
2245
2246 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2247 // Can't assert the method_holder is the same because the new method has the
2248 // scratch method holder.
2249 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2250 == new_method->method_holder()->class_loader() ||
2251 new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2252 "changing to a different class loader");
2253 // Just change the method in place, jmethodID pointer doesn't change.
2254 *((Method**)jmid) = new_method;
2255 }
2256
2257 bool Method::is_method_id(jmethodID mid) {
2258 Method* m = resolve_jmethod_id(mid);
2259 assert(m != NULL, "should be called with non-null method");
2260 InstanceKlass* ik = m->method_holder();
2261 ClassLoaderData* cld = ik->class_loader_data();
2262 if (cld->jmethod_ids() == NULL) return false;
2263 return (cld->jmethod_ids()->contains((Method**)mid));
2264 }
2265
2266 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2267 if (mid == NULL) return NULL;
2268 Method* o = resolve_jmethod_id(mid);
2269 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2270 return NULL;
2271 }
2272 return o;
2273 };
2274
2275 void Method::set_on_stack(const bool value) {
2276 // Set both the method itself and its constant pool. The constant pool
2277 // on stack means some method referring to it is also on the stack.
2278 constants()->set_on_stack(value);
2279
2280 bool already_set = on_stack();
2281 _access_flags.set_on_stack(value);
2282 if (value && !already_set) {
2283 MetadataOnStackMark::record(this);
2284 }
2285 assert(!value || !is_old() || is_obsolete() || is_running_emcp(),
2286 "emcp methods cannot run after emcp bit is cleared");
2287 }
2288
2289 // Called when the class loader is unloaded to make all methods weak.
2290 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2291 loader_data->jmethod_ids()->clear_all_methods();
2292 }
2293
2294 bool Method::has_method_vptr(const void* ptr) {
2295 Method m;
2296 // This assumes that the vtbl pointer is the first word of a C++ object.
2297 return dereference_vptr(&m) == dereference_vptr(ptr);
2298 }
2299
2300 // Check that this pointer is valid by checking that the vtbl pointer matches
2301 bool Method::is_valid_method(const Method* m) {
2302 if (m == NULL) {
2303 return false;
2304 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2305 // Quick sanity check on pointer.
2306 return false;
2307 } else if (m->is_shared()) {
2308 return MetaspaceShared::is_valid_shared_method(m);
2309 } else if (Metaspace::contains_non_shared(m)) {
2310 return has_method_vptr((const void*)m);
2311 } else {
2312 return false;
2313 }
2314 }
2315
2316 #ifndef PRODUCT
2317 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2318 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2319 }
2320 #endif // PRODUCT
2321
2322
2323 // Printing
2324
2325 #ifndef PRODUCT
2326
2327 void Method::print_on(outputStream* st) const {
2328 ResourceMark rm;
2329 assert(is_method(), "must be method");
2330 st->print_cr("%s", internal_name());
2331 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2332 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2333 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2334 constants()->print_value_on(st); st->cr();
2335 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2336 st->print (" - name: "); name()->print_value_on(st); st->cr();
2337 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2338 st->print_cr(" - max stack: %d", max_stack());
2339 st->print_cr(" - max locals: %d", max_locals());
2340 st->print_cr(" - size of params: %d", size_of_parameters());
2341 st->print_cr(" - method size: %d", method_size());
2342 if (intrinsic_id() != vmIntrinsics::_none)
2343 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2344 if (highest_comp_level() != CompLevel_none)
2345 st->print_cr(" - highest level: %d", highest_comp_level());
2346 st->print_cr(" - vtable index: %d", _vtable_index);
2347 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2348 st->print( " - adapters: ");
2349 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2350 if (a == NULL)
2351 st->print_cr(INTPTR_FORMAT, p2i(a));
2352 else
2353 a->print_adapter_on(st);
2354 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2355 st->print_cr(" - code size: %d", code_size());
2356 if (code_size() != 0) {
2357 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2358 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2359 }
2360 if (method_data() != NULL) {
2361 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2362 }
2363 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2364 if (checked_exceptions_length() > 0) {
2365 CheckedExceptionElement* table = checked_exceptions_start();
2366 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2367 if (Verbose) {
2368 for (int i = 0; i < checked_exceptions_length(); i++) {
2369 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2370 }
2371 }
2372 }
2373 if (has_linenumber_table()) {
2374 u_char* table = compressed_linenumber_table();
2375 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2376 if (Verbose) {
2377 CompressedLineNumberReadStream stream(table);
2378 while (stream.read_pair()) {
2379 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2380 }
2381 }
2382 }
2383 st->print_cr(" - localvar length: %d", localvariable_table_length());
2384 if (localvariable_table_length() > 0) {
2385 LocalVariableTableElement* table = localvariable_table_start();
2386 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2387 if (Verbose) {
2388 for (int i = 0; i < localvariable_table_length(); i++) {
2389 int bci = table[i].start_bci;
2390 int len = table[i].length;
2391 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2392 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2393 int slot = table[i].slot;
2394 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2395 }
2396 }
2397 }
2398 if (code() != NULL) {
2399 st->print (" - compiled code: ");
2400 code()->print_value_on(st);
2401 }
2402 if (is_native()) {
2403 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2404 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2405 }
2406 }
2407
2408 void Method::print_linkage_flags(outputStream* st) {
2409 access_flags().print_on(st);
2410 if (is_default_method()) {
2411 st->print("default ");
2412 }
2413 if (is_overpass()) {
2414 st->print("overpass ");
2415 }
2416 }
2417 #endif //PRODUCT
2418
2419 void Method::print_value_on(outputStream* st) const {
2420 assert(is_method(), "must be method");
2421 st->print("%s", internal_name());
2422 print_address_on(st);
2423 st->print(" ");
2424 name()->print_value_on(st);
2425 st->print(" ");
2426 signature()->print_value_on(st);
2427 st->print(" in ");
2428 method_holder()->print_value_on(st);
2429 if (WizardMode) st->print("#%d", _vtable_index);
2430 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2431 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2432 }
2433
2434 // LogTouchedMethods and PrintTouchedMethods
2435
2436 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2437 // the Method may be garbage collected. Let's roll our own hash table.
2438 class TouchedMethodRecord : CHeapObj<mtTracing> {
2439 public:
2440 // It's OK to store Symbols here because they will NOT be GC'ed if
2441 // LogTouchedMethods is enabled.
2442 TouchedMethodRecord* _next;
2443 Symbol* _class_name;
2444 Symbol* _method_name;
2445 Symbol* _method_signature;
2446 };
2447
2448 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2449 static TouchedMethodRecord** _touched_method_table = NULL;
2450
2451 void Method::log_touched(TRAPS) {
2452
2453 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2454 Symbol* my_class = klass_name();
2455 Symbol* my_name = name();
2456 Symbol* my_sig = signature();
2457
2458 unsigned int hash = my_class->identity_hash() +
2459 my_name->identity_hash() +
2460 my_sig->identity_hash();
2461 juint index = juint(hash) % table_size;
2462
2463 MutexLocker ml(THREAD, TouchedMethodLog_lock);
2464 if (_touched_method_table == NULL) {
2465 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2466 mtTracing, CURRENT_PC);
2467 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2468 }
2469
2470 TouchedMethodRecord* ptr = _touched_method_table[index];
2471 while (ptr) {
2472 if (ptr->_class_name == my_class &&
2473 ptr->_method_name == my_name &&
2474 ptr->_method_signature == my_sig) {
2475 return;
2476 }
2477 if (ptr->_next == NULL) break;
2478 ptr = ptr->_next;
2479 }
2480 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2481 my_class->increment_refcount();
2482 my_name->increment_refcount();
2483 my_sig->increment_refcount();
2484 nptr->_class_name = my_class;
2485 nptr->_method_name = my_name;
2486 nptr->_method_signature = my_sig;
2487 nptr->_next = NULL;
2488
2489 if (ptr == NULL) {
2490 // first
2491 _touched_method_table[index] = nptr;
2492 } else {
2493 ptr->_next = nptr;
2494 }
2495 }
2496
2497 void Method::print_touched_methods(outputStream* out) {
2498 MutexLocker ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2499 out->print_cr("# Method::print_touched_methods version 1");
2500 if (_touched_method_table) {
2501 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2502 TouchedMethodRecord* ptr = _touched_method_table[i];
2503 while(ptr) {
2504 ptr->_class_name->print_symbol_on(out); out->print(".");
2505 ptr->_method_name->print_symbol_on(out); out->print(":");
2506 ptr->_method_signature->print_symbol_on(out); out->cr();
2507 ptr = ptr->_next;
2508 }
2509 }
2510 }
2511 }
2512
2513 // Verification
2514
2515 void Method::verify_on(outputStream* st) {
2516 guarantee(is_method(), "object must be method");
2517 guarantee(constants()->is_constantPool(), "should be constant pool");
2518 MethodData* md = method_data();
2519 guarantee(md == NULL ||
2520 md->is_methodData(), "should be method data");
2521 }