1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/classLoaderDataGraph.hpp"
27 #include "classfile/metadataOnStackMark.hpp"
28 #include "classfile/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/heapInspection.hpp"
43 #include "memory/metadataFactory.hpp"
44 #include "memory/metaspaceClosure.hpp"
45 #include "memory/metaspaceShared.hpp"
46 #include "memory/oopFactory.hpp"
47 #include "memory/resourceArea.hpp"
48 #include "memory/universe.hpp"
49 #include "oops/constMethod.hpp"
50 #include "oops/constantPool.hpp"
51 #include "oops/method.inline.hpp"
52 #include "oops/methodData.hpp"
53 #include "oops/objArrayKlass.hpp"
54 #include "oops/objArrayOop.inline.hpp"
55 #include "oops/oop.inline.hpp"
56 #include "oops/symbol.hpp"
57 #include "prims/jvmtiExport.hpp"
58 #include "prims/methodHandles.hpp"
59 #include "prims/nativeLookup.hpp"
60 #include "runtime/arguments.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(MethodData_lock, THREAD);
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(counters, &_method_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 void Method::compute_size_of_parameters(Thread *thread) {
581 ArgumentSizeComputer asc(signature());
582 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
583 }
584
585 bool Method::is_empty_method() const {
586 return code_size() == 1
587 && *code_base() == Bytecodes::_return;
588 }
589
590 bool Method::is_vanilla_constructor() const {
591 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
592 // which only calls the superclass vanilla constructor and possibly does stores of
593 // zero constants to local fields:
594 //
595 // aload_0
596 // invokespecial
597 // indexbyte1
598 // indexbyte2
599 //
600 // followed by an (optional) sequence of:
601 //
602 // aload_0
603 // aconst_null / iconst_0 / fconst_0 / dconst_0
604 // putfield
605 // indexbyte1
606 // indexbyte2
607 //
608 // followed by:
609 //
610 // return
611
612 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
613 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
614 int size = code_size();
615 // Check if size match
616 if (size == 0 || size % 5 != 0) return false;
617 address cb = code_base();
618 int last = size - 1;
619 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
620 // Does not call superclass default constructor
621 return false;
622 }
623 // Check optional sequence
624 for (int i = 4; i < last; i += 5) {
625 if (cb[i] != Bytecodes::_aload_0) return false;
626 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
627 if (cb[i+2] != Bytecodes::_putfield) return false;
628 }
629 return true;
630 }
631
632
633 bool Method::compute_has_loops_flag() {
634 BytecodeStream bcs(methodHandle(Thread::current(), this));
635 Bytecodes::Code bc;
636
637 while ((bc = bcs.next()) >= 0) {
638 switch( bc ) {
639 case Bytecodes::_ifeq:
640 case Bytecodes::_ifnull:
641 case Bytecodes::_iflt:
642 case Bytecodes::_ifle:
643 case Bytecodes::_ifne:
644 case Bytecodes::_ifnonnull:
645 case Bytecodes::_ifgt:
646 case Bytecodes::_ifge:
647 case Bytecodes::_if_icmpeq:
648 case Bytecodes::_if_icmpne:
649 case Bytecodes::_if_icmplt:
650 case Bytecodes::_if_icmpgt:
651 case Bytecodes::_if_icmple:
652 case Bytecodes::_if_icmpge:
653 case Bytecodes::_if_acmpeq:
654 case Bytecodes::_if_acmpne:
655 case Bytecodes::_goto:
656 case Bytecodes::_jsr:
657 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
658 break;
659
660 case Bytecodes::_goto_w:
661 case Bytecodes::_jsr_w:
662 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
663 break;
664
665 default:
666 break;
667 }
668 }
669 _access_flags.set_loops_flag_init();
670 return _access_flags.has_loops();
671 }
672
673 bool Method::is_final_method(AccessFlags class_access_flags) const {
674 // or "does_not_require_vtable_entry"
675 // default method or overpass can occur, is not final (reuses vtable entry)
676 // private methods in classes get vtable entries for backward class compatibility.
677 if (is_overpass() || is_default_method()) return false;
678 return is_final() || class_access_flags.is_final();
679 }
680
681 bool Method::is_final_method() const {
682 return is_final_method(method_holder()->access_flags());
683 }
684
685 bool Method::is_default_method() const {
686 if (method_holder() != NULL &&
687 method_holder()->is_interface() &&
688 !is_abstract() && !is_private()) {
689 return true;
690 } else {
691 return false;
692 }
693 }
694
695 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
696 if (is_final_method(class_access_flags)) return true;
697 #ifdef ASSERT
698 ResourceMark rm;
699 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
700 if (class_access_flags.is_interface()) {
701 assert(is_nonv == is_static() || is_nonv == is_private(),
702 "nonvirtual unexpected for non-static, non-private: %s",
703 name_and_sig_as_C_string());
704 }
705 #endif
706 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
707 return vtable_index() == nonvirtual_vtable_index;
708 }
709
710 bool Method::can_be_statically_bound() const {
711 return can_be_statically_bound(method_holder()->access_flags());
712 }
713
714 bool Method::can_be_statically_bound(InstanceKlass* context) const {
715 return (method_holder() == context) && can_be_statically_bound();
716 }
717
718 bool Method::is_accessor() const {
719 return is_getter() || is_setter();
720 }
721
722 bool Method::is_getter() const {
723 if (code_size() != 5) return false;
724 if (size_of_parameters() != 1) return false;
725 if (java_code_at(0) != Bytecodes::_aload_0) return false;
726 if (java_code_at(1) != Bytecodes::_getfield) return false;
727 switch (java_code_at(4)) {
728 case Bytecodes::_ireturn:
729 case Bytecodes::_lreturn:
730 case Bytecodes::_freturn:
731 case Bytecodes::_dreturn:
732 case Bytecodes::_areturn:
733 break;
734 default:
735 return false;
736 }
737 return true;
738 }
739
740 bool Method::is_setter() const {
741 if (code_size() != 6) return false;
742 if (java_code_at(0) != Bytecodes::_aload_0) return false;
743 switch (java_code_at(1)) {
744 case Bytecodes::_iload_1:
745 case Bytecodes::_aload_1:
746 case Bytecodes::_fload_1:
747 if (size_of_parameters() != 2) return false;
748 break;
749 case Bytecodes::_dload_1:
750 case Bytecodes::_lload_1:
751 if (size_of_parameters() != 3) return false;
752 break;
753 default:
754 return false;
755 }
756 if (java_code_at(2) != Bytecodes::_putfield) return false;
757 if (java_code_at(5) != Bytecodes::_return) return false;
758 return true;
759 }
760
761 bool Method::is_constant_getter() const {
762 int last_index = code_size() - 1;
763 // Check if the first 1-3 bytecodes are a constant push
764 // and the last bytecode is a return.
765 return (2 <= code_size() && code_size() <= 4 &&
766 Bytecodes::is_const(java_code_at(0)) &&
767 Bytecodes::length_for(java_code_at(0)) == last_index &&
768 Bytecodes::is_return(java_code_at(last_index)));
769 }
770
771 bool Method::is_initializer() const {
772 return is_object_initializer() || is_static_initializer();
773 }
774
775 bool Method::has_valid_initializer_flags() const {
776 return (is_static() ||
777 method_holder()->major_version() < 51);
778 }
779
780 bool Method::is_static_initializer() const {
781 // For classfiles version 51 or greater, ensure that the clinit method is
782 // static. Non-static methods with the name "<clinit>" are not static
783 // initializers. (older classfiles exempted for backward compatibility)
784 return name() == vmSymbols::class_initializer_name() &&
785 has_valid_initializer_flags();
786 }
787
788 bool Method::is_object_initializer() const {
789 return name() == vmSymbols::object_initializer_name();
790 }
791
792 bool Method::needs_clinit_barrier() const {
793 return is_static() && !method_holder()->is_initialized();
794 }
795
796 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
797 int length = method->checked_exceptions_length();
798 if (length == 0) { // common case
799 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
800 } else {
801 methodHandle h_this(THREAD, method);
802 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
803 objArrayHandle mirrors (THREAD, m_oop);
804 for (int i = 0; i < length; i++) {
805 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
806 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
807 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
808 mirrors->obj_at_put(i, k->java_mirror());
809 }
810 return mirrors;
811 }
812 };
813
814
815 int Method::line_number_from_bci(int bci) const {
816 int best_bci = 0;
817 int best_line = -1;
818 if (bci == SynchronizationEntryBCI) bci = 0;
819 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
820 // The line numbers are a short array of 2-tuples [start_pc, line_number].
821 // Not necessarily sorted and not necessarily one-to-one.
822 CompressedLineNumberReadStream stream(compressed_linenumber_table());
823 while (stream.read_pair()) {
824 if (stream.bci() == bci) {
825 // perfect match
826 return stream.line();
827 } else {
828 // update best_bci/line
829 if (stream.bci() < bci && stream.bci() >= best_bci) {
830 best_bci = stream.bci();
831 best_line = stream.line();
832 }
833 }
834 }
835 }
836 return best_line;
837 }
838
839
840 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
841 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
842 Thread *thread = Thread::current();
843 Symbol* klass_name = constants()->klass_name_at(klass_index);
844 Handle loader(thread, method_holder()->class_loader());
845 Handle prot (thread, method_holder()->protection_domain());
846 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
847 } else {
848 return true;
849 }
850 }
851
852
853 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
854 int klass_index = constants()->klass_ref_index_at(refinfo_index);
855 if (must_be_resolved) {
856 // Make sure klass is resolved in constantpool.
857 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
858 }
859 return is_klass_loaded_by_klass_index(klass_index);
860 }
861
862
863 void Method::set_native_function(address function, bool post_event_flag) {
864 assert(function != NULL, "use clear_native_function to unregister natives");
865 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
866 address* native_function = native_function_addr();
867
868 // We can see racers trying to place the same native function into place. Once
869 // is plenty.
870 address current = *native_function;
871 if (current == function) return;
872 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
873 function != NULL) {
874 // native_method_throw_unsatisfied_link_error_entry() should only
875 // be passed when post_event_flag is false.
876 assert(function !=
877 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
878 "post_event_flag mis-match");
879
880 // post the bind event, and possible change the bind function
881 JvmtiExport::post_native_method_bind(this, &function);
882 }
883 *native_function = function;
884 // This function can be called more than once. We must make sure that we always
885 // use the latest registered method -> check if a stub already has been generated.
886 // If so, we have to make it not_entrant.
887 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
888 if (nm != NULL) {
889 nm->make_not_entrant();
890 }
891 }
892
893
894 bool Method::has_native_function() const {
895 if (is_method_handle_intrinsic())
896 return false; // special-cased in SharedRuntime::generate_native_wrapper
897 address func = native_function();
898 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
899 }
900
901
902 void Method::clear_native_function() {
903 // Note: is_method_handle_intrinsic() is allowed here.
904 set_native_function(
905 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
906 !native_bind_event_is_interesting);
907 this->unlink_code();
908 }
909
910
911 void Method::set_signature_handler(address handler) {
912 address* signature_handler = signature_handler_addr();
913 *signature_handler = handler;
914 }
915
916
917 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
918 assert(reason != NULL, "must provide a reason");
919 if (PrintCompilation && report) {
920 ttyLocker ttyl;
921 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
922 if (comp_level == CompLevel_all) {
923 tty->print("all levels ");
924 } else {
925 tty->print("level %d ", comp_level);
926 }
927 this->print_short_name(tty);
928 int size = this->code_size();
929 if (size > 0) {
930 tty->print(" (%d bytes)", size);
931 }
932 if (reason != NULL) {
933 tty->print(" %s", reason);
934 }
935 tty->cr();
936 }
937 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
938 ttyLocker ttyl;
939 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
940 os::current_thread_id(), is_osr, comp_level);
941 if (reason != NULL) {
942 xtty->print(" reason=\'%s\'", reason);
943 }
944 xtty->method(this);
945 xtty->stamp();
946 xtty->end_elem();
947 }
948 }
949
950 bool Method::is_always_compilable() const {
951 // Generated adapters must be compiled
952 if (is_method_handle_intrinsic() && is_synthetic()) {
953 assert(!is_not_c1_compilable(), "sanity check");
954 assert(!is_not_c2_compilable(), "sanity check");
955 return true;
956 }
957
958 return false;
959 }
960
961 bool Method::is_not_compilable(int comp_level) const {
962 if (number_of_breakpoints() > 0)
963 return true;
964 if (is_always_compilable())
965 return false;
966 if (comp_level == CompLevel_any)
967 return is_not_c1_compilable() || is_not_c2_compilable();
968 if (is_c1_compile(comp_level))
969 return is_not_c1_compilable();
970 if (is_c2_compile(comp_level))
971 return is_not_c2_compilable();
972 return false;
973 }
974
975 // call this when compiler finds that this method is not compilable
976 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
977 if (is_always_compilable()) {
978 // Don't mark a method which should be always compilable
979 return;
980 }
981 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
982 if (comp_level == CompLevel_all) {
983 set_not_c1_compilable();
984 set_not_c2_compilable();
985 } else {
986 if (is_c1_compile(comp_level))
987 set_not_c1_compilable();
988 if (is_c2_compile(comp_level))
989 set_not_c2_compilable();
990 }
991 CompilationPolicy::policy()->disable_compilation(this);
992 assert(!CompilationPolicy::can_be_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
993 }
994
995 bool Method::is_not_osr_compilable(int comp_level) const {
996 if (is_not_compilable(comp_level))
997 return true;
998 if (comp_level == CompLevel_any)
999 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
1000 if (is_c1_compile(comp_level))
1001 return is_not_c1_osr_compilable();
1002 if (is_c2_compile(comp_level))
1003 return is_not_c2_osr_compilable();
1004 return false;
1005 }
1006
1007 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
1008 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
1009 if (comp_level == CompLevel_all) {
1010 set_not_c1_osr_compilable();
1011 set_not_c2_osr_compilable();
1012 } else {
1013 if (is_c1_compile(comp_level))
1014 set_not_c1_osr_compilable();
1015 if (is_c2_compile(comp_level))
1016 set_not_c2_osr_compilable();
1017 }
1018 CompilationPolicy::policy()->disable_compilation(this);
1019 assert(!CompilationPolicy::can_be_osr_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1020 }
1021
1022 // Revert to using the interpreter and clear out the nmethod
1023 void Method::clear_code() {
1024 // this may be NULL if c2i adapters have not been made yet
1025 // Only should happen at allocate time.
1026 if (adapter() == NULL) {
1027 _from_compiled_entry = NULL;
1028 } else {
1029 _from_compiled_entry = adapter()->get_c2i_entry();
1030 }
1031 OrderAccess::storestore();
1032 _from_interpreted_entry = _i2i_entry;
1033 OrderAccess::storestore();
1034 _code = NULL;
1035 }
1036
1037 void Method::unlink_code(CompiledMethod *compare) {
1038 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1039 // We need to check if either the _code or _from_compiled_code_entry_point
1040 // refer to this nmethod because there is a race in setting these two fields
1041 // in Method* as seen in bugid 4947125.
1042 // If the vep() points to the zombie nmethod, the memory for the nmethod
1043 // could be flushed and the compiler and vtable stubs could still call
1044 // through it.
1045 if (code() == compare ||
1046 from_compiled_entry() == compare->verified_entry_point()) {
1047 clear_code();
1048 }
1049 }
1050
1051 void Method::unlink_code() {
1052 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1053 clear_code();
1054 }
1055
1056 #if INCLUDE_CDS
1057 // Called by class data sharing to remove any entry points (which are not shared)
1058 void Method::unlink_method() {
1059 _code = NULL;
1060
1061 Arguments::assert_is_dumping_archive();
1062 // Set the values to what they should be at run time. Note that
1063 // this Method can no longer be executed during dump time.
1064 _i2i_entry = Interpreter::entry_for_cds_method(methodHandle(Thread::current(), this));
1065 _from_interpreted_entry = _i2i_entry;
1066
1067 if (DynamicDumpSharedSpaces) {
1068 assert(_from_compiled_entry != NULL, "sanity");
1069 } else {
1070 // TODO: Simplify the adapter trampoline allocation for static archiving.
1071 // Remove the use of CDSAdapterHandlerEntry.
1072 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
1073 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
1074 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
1075 assert(*((int*)_from_compiled_entry) == 0,
1076 "must be NULL during dump time, to be initialized at run time");
1077 }
1078
1079 if (is_native()) {
1080 *native_function_addr() = NULL;
1081 set_signature_handler(NULL);
1082 }
1083 NOT_PRODUCT(set_compiled_invocation_count(0);)
1084
1085 set_method_data(NULL);
1086 clear_method_counters();
1087 }
1088 #endif
1089
1090 /****************************************************************************
1091 // The following illustrates how the entries work for CDS shared Methods:
1092 //
1093 // Our goal is to delay writing into a shared Method until it's compiled.
1094 // Hence, we want to determine the initial values for _i2i_entry,
1095 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
1096 //
1097 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
1098 // They also have similar signatures so that they will share the same
1099 // AdapterHandlerEntry.
1100 //
1101 // _adapter_trampoline points to a fixed location in the RW section of
1102 // the CDS archive. This location initially contains a NULL pointer. When the
1103 // first of method A or B is linked, an AdapterHandlerEntry is allocated
1104 // dynamically, and its c2i/i2c entries are generated.
1105 //
1106 // _i2i_entry and _from_interpreted_entry initially points to the same
1107 // (fixed) location in the CODE section of the CDS archive. This contains
1108 // an unconditional branch to the actual entry for "zero_locals", which is
1109 // generated at run time and may be on an arbitrary address. Thus, the
1110 // unconditional branch is also generated at run time to jump to the correct
1111 // address.
1112 //
1113 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1114 // section. This address has enough space for an unconditional branch
1115 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1116 // initialized, and the address for the actual c2i_entry is known, we emit a
1117 // branch instruction here to branch to the actual c2i_entry.
1118 //
1119 // The effect of the extra branch on the i2i and c2i entries is negligible.
1120 //
1121 // The reason for putting _adapter_trampoline in RO is many shared Methods
1122 // share the same AdapterHandlerEntry, so we can save space in the RW section
1123 // by having the extra indirection.
1124
1125
1126 [Method A: RW]
1127 _constMethod ----> [ConstMethod: RO]
1128 _adapter_trampoline -----------+
1129 |
1130 _i2i_entry (same value as method B) |
1131 _from_interpreted_entry (same value as method B) |
1132 _from_compiled_entry (same value as method B) |
1133 |
1134 |
1135 [Method B: RW] +--------+
1136 _constMethod ----> [ConstMethod: RO] |
1137 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1138 |
1139 +-------------------------------+
1140 |
1141 +----> [AdapterHandlerEntry] (allocated at run time)
1142 _fingerprint
1143 _c2i_entry ---------------------------------+->[c2i entry..]
1144 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1145 _from_interpreted_entry | _c2i_unverified_entry | |
1146 | | _c2i_no_clinit_check_entry| |
1147 | | (_cds_entry_table: CODE) | |
1148 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1149 | | (allocated at run time) | |
1150 | | ... [asm code ...] | |
1151 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1152 | | |
1153 | | |
1154 +-[compiled]-------------------------------------------------------------------+ |
1155 |
1156 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1157 [jmp c2i_entry] ------------------------------------------------------+
1158
1159 ***/
1160
1161 // Called when the method_holder is getting linked. Setup entrypoints so the method
1162 // is ready to be called from interpreter, compiler, and vtables.
1163 void Method::link_method(const methodHandle& h_method, TRAPS) {
1164 // If the code cache is full, we may reenter this function for the
1165 // leftover methods that weren't linked.
1166 if (is_shared()) {
1167 address entry = Interpreter::entry_for_cds_method(h_method);
1168 assert(entry != NULL && entry == _i2i_entry,
1169 "should be correctly set during dump time");
1170 if (adapter() != NULL) {
1171 return;
1172 }
1173 assert(entry == _from_interpreted_entry,
1174 "should be correctly set during dump time");
1175 } else if (_i2i_entry != NULL) {
1176 return;
1177 }
1178 assert( _code == NULL, "nothing compiled yet" );
1179
1180 // Setup interpreter entrypoint
1181 assert(this == h_method(), "wrong h_method()" );
1182
1183 if (!is_shared()) {
1184 assert(adapter() == NULL, "init'd to NULL");
1185 address entry = Interpreter::entry_for_method(h_method);
1186 assert(entry != NULL, "interpreter entry must be non-null");
1187 // Sets both _i2i_entry and _from_interpreted_entry
1188 set_interpreter_entry(entry);
1189 }
1190
1191 // Don't overwrite already registered native entries.
1192 if (is_native() && !has_native_function()) {
1193 set_native_function(
1194 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1195 !native_bind_event_is_interesting);
1196 }
1197
1198 // Setup compiler entrypoint. This is made eagerly, so we do not need
1199 // special handling of vtables. An alternative is to make adapters more
1200 // lazily by calling make_adapter() from from_compiled_entry() for the
1201 // normal calls. For vtable calls life gets more complicated. When a
1202 // call-site goes mega-morphic we need adapters in all methods which can be
1203 // called from the vtable. We need adapters on such methods that get loaded
1204 // later. Ditto for mega-morphic itable calls. If this proves to be a
1205 // problem we'll make these lazily later.
1206 (void) make_adapters(h_method, CHECK);
1207
1208 // ONLY USE the h_method now as make_adapter may have blocked
1209
1210 }
1211
1212 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1213 // Adapters for compiled code are made eagerly here. They are fairly
1214 // small (generally < 100 bytes) and quick to make (and cached and shared)
1215 // so making them eagerly shouldn't be too expensive.
1216 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1217 if (adapter == NULL ) {
1218 if (!is_init_completed()) {
1219 // Don't throw exceptions during VM initialization because java.lang.* classes
1220 // might not have been initialized, causing problems when constructing the
1221 // Java exception object.
1222 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1223 } else {
1224 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1225 }
1226 }
1227
1228 if (mh->is_shared()) {
1229 assert(mh->adapter() == adapter, "must be");
1230 assert(mh->_from_compiled_entry != NULL, "must be");
1231 } else {
1232 mh->set_adapter_entry(adapter);
1233 mh->_from_compiled_entry = adapter->get_c2i_entry();
1234 }
1235 return adapter->get_c2i_entry();
1236 }
1237
1238 void Method::restore_unshareable_info(TRAPS) {
1239 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1240
1241 // Since restore_unshareable_info can be called more than once for a method, don't
1242 // redo any work.
1243 if (adapter() == NULL) {
1244 methodHandle mh(THREAD, this);
1245 link_method(mh, CHECK);
1246 }
1247 }
1248
1249 address Method::from_compiled_entry_no_trampoline() const {
1250 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1251 if (code) {
1252 return code->verified_entry_point();
1253 } else {
1254 return adapter()->get_c2i_entry();
1255 }
1256 }
1257
1258 // The verified_code_entry() must be called when a invoke is resolved
1259 // on this method.
1260
1261 // It returns the compiled code entry point, after asserting not null.
1262 // This function is called after potential safepoints so that nmethod
1263 // or adapter that it points to is still live and valid.
1264 // This function must not hit a safepoint!
1265 address Method::verified_code_entry() {
1266 debug_only(NoSafepointVerifier nsv;)
1267 assert(_from_compiled_entry != NULL, "must be set");
1268 return _from_compiled_entry;
1269 }
1270
1271 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1272 // (could be racing a deopt).
1273 // Not inline to avoid circular ref.
1274 bool Method::check_code() const {
1275 // cached in a register or local. There's a race on the value of the field.
1276 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1277 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1278 }
1279
1280 // Install compiled code. Instantly it can execute.
1281 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1282 assert_lock_strong(CompiledMethod_lock);
1283 assert( code, "use clear_code to remove code" );
1284 assert( mh->check_code(), "" );
1285
1286 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1287
1288 // These writes must happen in this order, because the interpreter will
1289 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1290 // which jumps to _from_compiled_entry.
1291 mh->_code = code; // Assign before allowing compiled code to exec
1292
1293 int comp_level = code->comp_level();
1294 // In theory there could be a race here. In practice it is unlikely
1295 // and not worth worrying about.
1296 if (comp_level > mh->highest_comp_level()) {
1297 mh->set_highest_comp_level(comp_level);
1298 }
1299
1300 OrderAccess::storestore();
1301 mh->_from_compiled_entry = code->verified_entry_point();
1302 OrderAccess::storestore();
1303 // Instantly compiled code can execute.
1304 if (!mh->is_method_handle_intrinsic())
1305 mh->_from_interpreted_entry = mh->get_i2c_entry();
1306 }
1307
1308
1309 bool Method::is_overridden_in(Klass* k) const {
1310 InstanceKlass* ik = InstanceKlass::cast(k);
1311
1312 if (ik->is_interface()) return false;
1313
1314 // If method is an interface, we skip it - except if it
1315 // is a miranda method
1316 if (method_holder()->is_interface()) {
1317 // Check that method is not a miranda method
1318 if (ik->lookup_method(name(), signature()) == NULL) {
1319 // No implementation exist - so miranda method
1320 return false;
1321 }
1322 return true;
1323 }
1324
1325 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1326 if (!has_vtable_index()) {
1327 return false;
1328 } else {
1329 Method* vt_m = ik->method_at_vtable(vtable_index());
1330 return vt_m != this;
1331 }
1332 }
1333
1334
1335 // give advice about whether this Method* should be cached or not
1336 bool Method::should_not_be_cached() const {
1337 if (is_old()) {
1338 // This method has been redefined. It is either EMCP or obsolete
1339 // and we don't want to cache it because that would pin the method
1340 // down and prevent it from being collectible if and when it
1341 // finishes executing.
1342 return true;
1343 }
1344
1345 // caching this method should be just fine
1346 return false;
1347 }
1348
1349
1350 /**
1351 * Returns true if this is one of the specially treated methods for
1352 * security related stack walks (like Reflection.getCallerClass).
1353 */
1354 bool Method::is_ignored_by_security_stack_walk() const {
1355 if (intrinsic_id() == vmIntrinsics::_invoke) {
1356 // This is Method.invoke() -- ignore it
1357 return true;
1358 }
1359 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1360 // This is an auxilary frame -- ignore it
1361 return true;
1362 }
1363 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1364 // This is an internal adapter frame for method handles -- ignore it
1365 return true;
1366 }
1367 return false;
1368 }
1369
1370
1371 // Constant pool structure for invoke methods:
1372 enum {
1373 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1374 _imcp_invoke_signature, // utf8: (variable Symbol*)
1375 _imcp_limit
1376 };
1377
1378 // Test if this method is an MH adapter frame generated by Java code.
1379 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1380 bool Method::is_compiled_lambda_form() const {
1381 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1382 }
1383
1384 // Test if this method is an internal MH primitive method.
1385 bool Method::is_method_handle_intrinsic() const {
1386 vmIntrinsics::ID iid = intrinsic_id();
1387 return (MethodHandles::is_signature_polymorphic(iid) &&
1388 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1389 }
1390
1391 bool Method::has_member_arg() const {
1392 vmIntrinsics::ID iid = intrinsic_id();
1393 return (MethodHandles::is_signature_polymorphic(iid) &&
1394 MethodHandles::has_member_arg(iid));
1395 }
1396
1397 // Make an instance of a signature-polymorphic internal MH primitive.
1398 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1399 Symbol* signature,
1400 TRAPS) {
1401 ResourceMark rm;
1402 methodHandle empty;
1403
1404 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1405 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1406 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1407 if (TraceMethodHandles) {
1408 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1409 }
1410
1411 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1412 name->increment_refcount();
1413 signature->increment_refcount();
1414
1415 int cp_length = _imcp_limit;
1416 ClassLoaderData* loader_data = holder->class_loader_data();
1417 constantPoolHandle cp;
1418 {
1419 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1420 cp = constantPoolHandle(THREAD, cp_oop);
1421 }
1422 cp->set_pool_holder(holder);
1423 cp->symbol_at_put(_imcp_invoke_name, name);
1424 cp->symbol_at_put(_imcp_invoke_signature, signature);
1425 cp->set_has_preresolution();
1426
1427 // decide on access bits: public or not?
1428 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1429 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1430 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1431 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1432
1433 methodHandle m;
1434 {
1435 InlineTableSizes sizes;
1436 Method* m_oop = Method::allocate(loader_data, 0,
1437 accessFlags_from(flags_bits), &sizes,
1438 ConstMethod::NORMAL, CHECK_(empty));
1439 m = methodHandle(THREAD, m_oop);
1440 }
1441 m->set_constants(cp());
1442 m->set_name_index(_imcp_invoke_name);
1443 m->set_signature_index(_imcp_invoke_signature);
1444 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1445 assert(m->signature() == signature, "");
1446 ResultTypeFinder rtf(signature);
1447 m->constMethod()->set_result_type(rtf.type());
1448 m->compute_size_of_parameters(THREAD);
1449 m->init_intrinsic_id();
1450 assert(m->is_method_handle_intrinsic(), "");
1451 #ifdef ASSERT
1452 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1453 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1454 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1455 #endif //ASSERT
1456
1457 // Finally, set up its entry points.
1458 assert(m->can_be_statically_bound(), "");
1459 m->set_vtable_index(Method::nonvirtual_vtable_index);
1460 m->link_method(m, CHECK_(empty));
1461
1462 if (TraceMethodHandles && (Verbose || WizardMode)) {
1463 ttyLocker ttyl;
1464 m->print_on(tty);
1465 }
1466
1467 return m;
1468 }
1469
1470 Klass* Method::check_non_bcp_klass(Klass* klass) {
1471 if (klass != NULL && klass->class_loader() != NULL) {
1472 if (klass->is_objArray_klass())
1473 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1474 return klass;
1475 }
1476 return NULL;
1477 }
1478
1479
1480 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1481 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1482 // Code below does not work for native methods - they should never get rewritten anyway
1483 assert(!m->is_native(), "cannot rewrite native methods");
1484 // Allocate new Method*
1485 AccessFlags flags = m->access_flags();
1486
1487 ConstMethod* cm = m->constMethod();
1488 int checked_exceptions_len = cm->checked_exceptions_length();
1489 int localvariable_len = cm->localvariable_table_length();
1490 int exception_table_len = cm->exception_table_length();
1491 int method_parameters_len = cm->method_parameters_length();
1492 int method_annotations_len = cm->method_annotations_length();
1493 int parameter_annotations_len = cm->parameter_annotations_length();
1494 int type_annotations_len = cm->type_annotations_length();
1495 int default_annotations_len = cm->default_annotations_length();
1496
1497 InlineTableSizes sizes(
1498 localvariable_len,
1499 new_compressed_linenumber_size,
1500 exception_table_len,
1501 checked_exceptions_len,
1502 method_parameters_len,
1503 cm->generic_signature_index(),
1504 method_annotations_len,
1505 parameter_annotations_len,
1506 type_annotations_len,
1507 default_annotations_len,
1508 0);
1509
1510 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1511 Method* newm_oop = Method::allocate(loader_data,
1512 new_code_length,
1513 flags,
1514 &sizes,
1515 m->method_type(),
1516 CHECK_(methodHandle()));
1517 methodHandle newm (THREAD, newm_oop);
1518
1519 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1520 ConstMethod* newcm = newm->constMethod();
1521 int new_const_method_size = newm->constMethod()->size();
1522
1523 // This works because the source and target are both Methods. Some compilers
1524 // (e.g., clang) complain that the target vtable pointer will be stomped,
1525 // so cast away newm()'s and m()'s Methodness.
1526 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1527
1528 // Create shallow copy of ConstMethod.
1529 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1530
1531 // Reset correct method/const method, method size, and parameter info
1532 newm->set_constMethod(newcm);
1533 newm->constMethod()->set_code_size(new_code_length);
1534 newm->constMethod()->set_constMethod_size(new_const_method_size);
1535 assert(newm->code_size() == new_code_length, "check");
1536 assert(newm->method_parameters_length() == method_parameters_len, "check");
1537 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1538 assert(newm->exception_table_length() == exception_table_len, "check");
1539 assert(newm->localvariable_table_length() == localvariable_len, "check");
1540 // Copy new byte codes
1541 memcpy(newm->code_base(), new_code, new_code_length);
1542 // Copy line number table
1543 if (new_compressed_linenumber_size > 0) {
1544 memcpy(newm->compressed_linenumber_table(),
1545 new_compressed_linenumber_table,
1546 new_compressed_linenumber_size);
1547 }
1548 // Copy method_parameters
1549 if (method_parameters_len > 0) {
1550 memcpy(newm->method_parameters_start(),
1551 m->method_parameters_start(),
1552 method_parameters_len * sizeof(MethodParametersElement));
1553 }
1554 // Copy checked_exceptions
1555 if (checked_exceptions_len > 0) {
1556 memcpy(newm->checked_exceptions_start(),
1557 m->checked_exceptions_start(),
1558 checked_exceptions_len * sizeof(CheckedExceptionElement));
1559 }
1560 // Copy exception table
1561 if (exception_table_len > 0) {
1562 memcpy(newm->exception_table_start(),
1563 m->exception_table_start(),
1564 exception_table_len * sizeof(ExceptionTableElement));
1565 }
1566 // Copy local variable number table
1567 if (localvariable_len > 0) {
1568 memcpy(newm->localvariable_table_start(),
1569 m->localvariable_table_start(),
1570 localvariable_len * sizeof(LocalVariableTableElement));
1571 }
1572 // Copy stackmap table
1573 if (m->has_stackmap_table()) {
1574 int code_attribute_length = m->stackmap_data()->length();
1575 Array<u1>* stackmap_data =
1576 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_(methodHandle()));
1577 memcpy((void*)stackmap_data->adr_at(0),
1578 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1579 newm->set_stackmap_data(stackmap_data);
1580 }
1581
1582 // copy annotations over to new method
1583 newcm->copy_annotations_from(loader_data, cm, CHECK_(methodHandle()));
1584 return newm;
1585 }
1586
1587 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1588 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1589 // because we are not loading from core libraries
1590 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1591 // which does not use the class default class loader so we check for its loader here
1592 const InstanceKlass* ik = InstanceKlass::cast(holder);
1593 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1594 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1595 }
1596
1597 // see if the klass name is well-known:
1598 Symbol* klass_name = ik->name();
1599 return vmSymbols::find_sid(klass_name);
1600 }
1601
1602 void Method::init_intrinsic_id() {
1603 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1604 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1605 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1606 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1607
1608 // the klass name is well-known:
1609 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1610 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1611
1612 // ditto for method and signature:
1613 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1614 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1615 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1616 && name_id == vmSymbols::NO_SID) {
1617 return;
1618 }
1619 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1620 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1621 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1622 && sig_id == vmSymbols::NO_SID) {
1623 return;
1624 }
1625 jshort flags = access_flags().as_short();
1626
1627 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1628 if (id != vmIntrinsics::_none) {
1629 set_intrinsic_id(id);
1630 if (id == vmIntrinsics::_Class_cast) {
1631 // Even if the intrinsic is rejected, we want to inline this simple method.
1632 set_force_inline(true);
1633 }
1634 return;
1635 }
1636
1637 // A few slightly irregular cases:
1638 switch (klass_id) {
1639 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1640 // Second chance: check in regular Math.
1641 switch (name_id) {
1642 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1643 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1644 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1645 // pretend it is the corresponding method in the non-strict class:
1646 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1647 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1648 break;
1649 default:
1650 break;
1651 }
1652 break;
1653
1654 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1655 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1656 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1657 if (!is_native()) break;
1658 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1659 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1660 id = vmIntrinsics::_none;
1661 break;
1662
1663 default:
1664 break;
1665 }
1666
1667 if (id != vmIntrinsics::_none) {
1668 // Set up its iid. It is an alias method.
1669 set_intrinsic_id(id);
1670 return;
1671 }
1672 }
1673
1674 // These two methods are static since a GC may move the Method
1675 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1676 if (!THREAD->can_call_java()) {
1677 // There is nothing useful this routine can do from within the Compile thread.
1678 // Hopefully, the signature contains only well-known classes.
1679 // We could scan for this and return true/false, but the caller won't care.
1680 return false;
1681 }
1682 bool sig_is_loaded = true;
1683 Handle class_loader(THREAD, m->method_holder()->class_loader());
1684 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1685 ResourceMark rm(THREAD);
1686 Symbol* signature = m->signature();
1687 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1688 if (ss.is_object()) {
1689 Symbol* sym = ss.as_symbol();
1690 Symbol* name = sym;
1691 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1692 protection_domain, THREAD);
1693 // We are loading classes eagerly. If a ClassNotFoundException or
1694 // a LinkageError was generated, be sure to ignore it.
1695 if (HAS_PENDING_EXCEPTION) {
1696 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1697 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1698 CLEAR_PENDING_EXCEPTION;
1699 } else {
1700 return false;
1701 }
1702 }
1703 if( klass == NULL) { sig_is_loaded = false; }
1704 }
1705 }
1706 return sig_is_loaded;
1707 }
1708
1709 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1710 Handle class_loader(THREAD, m->method_holder()->class_loader());
1711 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1712 ResourceMark rm(THREAD);
1713 Symbol* signature = m->signature();
1714 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1715 if (ss.type() == T_OBJECT) {
1716 Symbol* name = ss.as_symbol_or_null();
1717 if (name == NULL) return true;
1718 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1719 if (klass == NULL) return true;
1720 }
1721 }
1722 return false;
1723 }
1724
1725 // Exposed so field engineers can debug VM
1726 void Method::print_short_name(outputStream* st) {
1727 ResourceMark rm;
1728 #ifdef PRODUCT
1729 st->print(" %s::", method_holder()->external_name());
1730 #else
1731 st->print(" %s::", method_holder()->internal_name());
1732 #endif
1733 name()->print_symbol_on(st);
1734 if (WizardMode) signature()->print_symbol_on(st);
1735 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1736 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1737 }
1738
1739 // Comparer for sorting an object array containing
1740 // Method*s.
1741 static int method_comparator(Method* a, Method* b) {
1742 return a->name()->fast_compare(b->name());
1743 }
1744
1745 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1746 // default_methods also uses this without the ordering for fast find_method
1747 void Method::sort_methods(Array<Method*>* methods, bool set_idnums, method_comparator_func func) {
1748 int length = methods->length();
1749 if (length > 1) {
1750 if (func == NULL) {
1751 func = method_comparator;
1752 }
1753 {
1754 NoSafepointVerifier nsv;
1755 QuickSort::sort(methods->data(), length, func, /*idempotent=*/false);
1756 }
1757 // Reset method ordering
1758 if (set_idnums) {
1759 for (int i = 0; i < length; i++) {
1760 Method* m = methods->at(i);
1761 m->set_method_idnum(i);
1762 m->set_orig_method_idnum(i);
1763 }
1764 }
1765 }
1766 }
1767
1768 //-----------------------------------------------------------------------------------
1769 // Non-product code unless JVM/TI needs it
1770
1771 #if !defined(PRODUCT) || INCLUDE_JVMTI
1772 class SignatureTypePrinter : public SignatureTypeNames {
1773 private:
1774 outputStream* _st;
1775 bool _use_separator;
1776
1777 void type_name(const char* name) {
1778 if (_use_separator) _st->print(", ");
1779 _st->print("%s", name);
1780 _use_separator = true;
1781 }
1782
1783 public:
1784 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1785 _st = st;
1786 _use_separator = false;
1787 }
1788
1789 void print_parameters() { _use_separator = false; iterate_parameters(); }
1790 void print_returntype() { _use_separator = false; iterate_returntype(); }
1791 };
1792
1793
1794 void Method::print_name(outputStream* st) {
1795 Thread *thread = Thread::current();
1796 ResourceMark rm(thread);
1797 st->print("%s ", is_static() ? "static" : "virtual");
1798 if (WizardMode) {
1799 st->print("%s.", method_holder()->internal_name());
1800 name()->print_symbol_on(st);
1801 signature()->print_symbol_on(st);
1802 } else {
1803 SignatureTypePrinter sig(signature(), st);
1804 sig.print_returntype();
1805 st->print(" %s.", method_holder()->internal_name());
1806 name()->print_symbol_on(st);
1807 st->print("(");
1808 sig.print_parameters();
1809 st->print(")");
1810 }
1811 }
1812 #endif // !PRODUCT || INCLUDE_JVMTI
1813
1814
1815 void Method::print_codes_on(outputStream* st) const {
1816 print_codes_on(0, code_size(), st);
1817 }
1818
1819 void Method::print_codes_on(int from, int to, outputStream* st) const {
1820 Thread *thread = Thread::current();
1821 ResourceMark rm(thread);
1822 methodHandle mh (thread, (Method*)this);
1823 BytecodeStream s(mh);
1824 s.set_interval(from, to);
1825 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1826 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1827 }
1828
1829 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1830 _bci = 0;
1831 _line = 0;
1832 };
1833
1834 bool CompressedLineNumberReadStream::read_pair() {
1835 jubyte next = read_byte();
1836 // Check for terminator
1837 if (next == 0) return false;
1838 if (next == 0xFF) {
1839 // Escape character, regular compression used
1840 _bci += read_signed_int();
1841 _line += read_signed_int();
1842 } else {
1843 // Single byte compression used
1844 _bci += next >> 3;
1845 _line += next & 0x7;
1846 }
1847 return true;
1848 }
1849
1850 #if INCLUDE_JVMTI
1851
1852 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1853 BreakpointInfo* bp = method_holder()->breakpoints();
1854 for (; bp != NULL; bp = bp->next()) {
1855 if (bp->match(this, bci)) {
1856 return bp->orig_bytecode();
1857 }
1858 }
1859 {
1860 ResourceMark rm;
1861 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1862 }
1863 return Bytecodes::_shouldnotreachhere;
1864 }
1865
1866 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1867 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1868 BreakpointInfo* bp = method_holder()->breakpoints();
1869 for (; bp != NULL; bp = bp->next()) {
1870 if (bp->match(this, bci)) {
1871 bp->set_orig_bytecode(code);
1872 // and continue, in case there is more than one
1873 }
1874 }
1875 }
1876
1877 void Method::set_breakpoint(int bci) {
1878 InstanceKlass* ik = method_holder();
1879 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1880 bp->set_next(ik->breakpoints());
1881 ik->set_breakpoints(bp);
1882 // do this last:
1883 bp->set(this);
1884 }
1885
1886 static void clear_matches(Method* m, int bci) {
1887 InstanceKlass* ik = m->method_holder();
1888 BreakpointInfo* prev_bp = NULL;
1889 BreakpointInfo* next_bp;
1890 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1891 next_bp = bp->next();
1892 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1893 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1894 // do this first:
1895 bp->clear(m);
1896 // unhook it
1897 if (prev_bp != NULL)
1898 prev_bp->set_next(next_bp);
1899 else
1900 ik->set_breakpoints(next_bp);
1901 delete bp;
1902 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1903 // at same location. So we have multiple matching (method_index and bci)
1904 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1905 // breakpoint for clear_breakpoint request and keep all other method versions
1906 // BreakpointInfo for future clear_breakpoint request.
1907 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1908 // which is being called when class is unloaded. We delete all the Breakpoint
1909 // information for all versions of method. We may not correctly restore the original
1910 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1911 // so these methods won't be used anymore.
1912 if (bci >= 0) {
1913 break;
1914 }
1915 } else {
1916 // This one is a keeper.
1917 prev_bp = bp;
1918 }
1919 }
1920 }
1921
1922 void Method::clear_breakpoint(int bci) {
1923 assert(bci >= 0, "");
1924 clear_matches(this, bci);
1925 }
1926
1927 void Method::clear_all_breakpoints() {
1928 clear_matches(this, -1);
1929 }
1930
1931 #endif // INCLUDE_JVMTI
1932
1933 int Method::invocation_count() {
1934 MethodCounters *mcs = method_counters();
1935 if (TieredCompilation) {
1936 MethodData* const mdo = method_data();
1937 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1938 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1939 return InvocationCounter::count_limit;
1940 } else {
1941 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1942 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1943 }
1944 } else {
1945 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1946 }
1947 }
1948
1949 int Method::backedge_count() {
1950 MethodCounters *mcs = method_counters();
1951 if (TieredCompilation) {
1952 MethodData* const mdo = method_data();
1953 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1954 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1955 return InvocationCounter::count_limit;
1956 } else {
1957 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1958 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1959 }
1960 } else {
1961 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1962 }
1963 }
1964
1965 int Method::highest_comp_level() const {
1966 const MethodCounters* mcs = method_counters();
1967 if (mcs != NULL) {
1968 return mcs->highest_comp_level();
1969 } else {
1970 return CompLevel_none;
1971 }
1972 }
1973
1974 int Method::highest_osr_comp_level() const {
1975 const MethodCounters* mcs = method_counters();
1976 if (mcs != NULL) {
1977 return mcs->highest_osr_comp_level();
1978 } else {
1979 return CompLevel_none;
1980 }
1981 }
1982
1983 void Method::set_highest_comp_level(int level) {
1984 MethodCounters* mcs = method_counters();
1985 if (mcs != NULL) {
1986 mcs->set_highest_comp_level(level);
1987 }
1988 }
1989
1990 void Method::set_highest_osr_comp_level(int level) {
1991 MethodCounters* mcs = method_counters();
1992 if (mcs != NULL) {
1993 mcs->set_highest_osr_comp_level(level);
1994 }
1995 }
1996
1997 #if INCLUDE_JVMTI
1998
1999 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
2000 _bci = bci;
2001 _name_index = m->name_index();
2002 _signature_index = m->signature_index();
2003 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
2004 if (_orig_bytecode == Bytecodes::_breakpoint)
2005 _orig_bytecode = m->orig_bytecode_at(_bci);
2006 _next = NULL;
2007 }
2008
2009 void BreakpointInfo::set(Method* method) {
2010 #ifdef ASSERT
2011 {
2012 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
2013 if (code == Bytecodes::_breakpoint)
2014 code = method->orig_bytecode_at(_bci);
2015 assert(orig_bytecode() == code, "original bytecode must be the same");
2016 }
2017 #endif
2018 Thread *thread = Thread::current();
2019 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
2020 method->incr_number_of_breakpoints(thread);
2021 {
2022 // Deoptimize all dependents on this method
2023 HandleMark hm(thread);
2024 methodHandle mh(thread, method);
2025 CodeCache::flush_dependents_on_method(mh);
2026 }
2027 }
2028
2029 void BreakpointInfo::clear(Method* method) {
2030 *method->bcp_from(_bci) = orig_bytecode();
2031 assert(method->number_of_breakpoints() > 0, "must not go negative");
2032 method->decr_number_of_breakpoints(Thread::current());
2033 }
2034
2035 #endif // INCLUDE_JVMTI
2036
2037 // jmethodID handling
2038
2039 // This is a block allocating object, sort of like JNIHandleBlock, only a
2040 // lot simpler.
2041 // It's allocated on the CHeap because once we allocate a jmethodID, we can
2042 // never get rid of it.
2043
2044 static const int min_block_size = 8;
2045
2046 class JNIMethodBlockNode : public CHeapObj<mtClass> {
2047 friend class JNIMethodBlock;
2048 Method** _methods;
2049 int _number_of_methods;
2050 int _top;
2051 JNIMethodBlockNode* _next;
2052
2053 public:
2054
2055 JNIMethodBlockNode(int num_methods = min_block_size);
2056
2057 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
2058
2059 void ensure_methods(int num_addl_methods) {
2060 if (_top < _number_of_methods) {
2061 num_addl_methods -= _number_of_methods - _top;
2062 if (num_addl_methods <= 0) {
2063 return;
2064 }
2065 }
2066 if (_next == NULL) {
2067 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
2068 } else {
2069 _next->ensure_methods(num_addl_methods);
2070 }
2071 }
2072 };
2073
2074 class JNIMethodBlock : public CHeapObj<mtClass> {
2075 JNIMethodBlockNode _head;
2076 JNIMethodBlockNode *_last_free;
2077 public:
2078 static Method* const _free_method;
2079
2080 JNIMethodBlock(int initial_capacity = min_block_size)
2081 : _head(initial_capacity), _last_free(&_head) {}
2082
2083 void ensure_methods(int num_addl_methods) {
2084 _last_free->ensure_methods(num_addl_methods);
2085 }
2086
2087 Method** add_method(Method* m) {
2088 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2089 if (b->_top < b->_number_of_methods) {
2090 // top points to the next free entry.
2091 int i = b->_top;
2092 b->_methods[i] = m;
2093 b->_top++;
2094 _last_free = b;
2095 return &(b->_methods[i]);
2096 } else if (b->_top == b->_number_of_methods) {
2097 // if the next free entry ran off the block see if there's a free entry
2098 for (int i = 0; i < b->_number_of_methods; i++) {
2099 if (b->_methods[i] == _free_method) {
2100 b->_methods[i] = m;
2101 _last_free = b;
2102 return &(b->_methods[i]);
2103 }
2104 }
2105 // Only check each block once for frees. They're very unlikely.
2106 // Increment top past the end of the block.
2107 b->_top++;
2108 }
2109 // need to allocate a next block.
2110 if (b->_next == NULL) {
2111 b->_next = _last_free = new JNIMethodBlockNode();
2112 }
2113 }
2114 guarantee(false, "Should always allocate a free block");
2115 return NULL;
2116 }
2117
2118 bool contains(Method** m) {
2119 if (m == NULL) return false;
2120 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2121 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2122 // This is a bit of extra checking, for two reasons. One is
2123 // that contains() deals with pointers that are passed in by
2124 // JNI code, so making sure that the pointer is aligned
2125 // correctly is valuable. The other is that <= and > are
2126 // technically not defined on pointers, so the if guard can
2127 // pass spuriously; no modern compiler is likely to make that
2128 // a problem, though (and if one did, the guard could also
2129 // fail spuriously, which would be bad).
2130 ptrdiff_t idx = m - b->_methods;
2131 if (b->_methods + idx == m) {
2132 return true;
2133 }
2134 }
2135 }
2136 return false; // not found
2137 }
2138
2139 // Doesn't really destroy it, just marks it as free so it can be reused.
2140 void destroy_method(Method** m) {
2141 #ifdef ASSERT
2142 assert(contains(m), "should be a methodID");
2143 #endif // ASSERT
2144 *m = _free_method;
2145 }
2146
2147 // During class unloading the methods are cleared, which is different
2148 // than freed.
2149 void clear_all_methods() {
2150 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2151 for (int i = 0; i< b->_number_of_methods; i++) {
2152 b->_methods[i] = NULL;
2153 }
2154 }
2155 }
2156 #ifndef PRODUCT
2157 int count_methods() {
2158 // count all allocated methods
2159 int count = 0;
2160 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2161 for (int i = 0; i< b->_number_of_methods; i++) {
2162 if (b->_methods[i] != _free_method) count++;
2163 }
2164 }
2165 return count;
2166 }
2167 #endif // PRODUCT
2168 };
2169
2170 // Something that can't be mistaken for an address or a markWord
2171 Method* const JNIMethodBlock::_free_method = (Method*)55;
2172
2173 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2174 _number_of_methods = MAX2(num_methods, min_block_size);
2175 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2176 for (int i = 0; i < _number_of_methods; i++) {
2177 _methods[i] = JNIMethodBlock::_free_method;
2178 }
2179 }
2180
2181 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2182 ClassLoaderData* cld = loader_data;
2183 if (!SafepointSynchronize::is_at_safepoint()) {
2184 // Have to add jmethod_ids() to class loader data thread-safely.
2185 // Also have to add the method to the list safely, which the cld lock
2186 // protects as well.
2187 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2188 if (cld->jmethod_ids() == NULL) {
2189 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2190 } else {
2191 cld->jmethod_ids()->ensure_methods(capacity);
2192 }
2193 } else {
2194 // At safepoint, we are single threaded and can set this.
2195 if (cld->jmethod_ids() == NULL) {
2196 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2197 } else {
2198 cld->jmethod_ids()->ensure_methods(capacity);
2199 }
2200 }
2201 }
2202
2203 // Add a method id to the jmethod_ids
2204 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2205 ClassLoaderData* cld = loader_data;
2206
2207 if (!SafepointSynchronize::is_at_safepoint()) {
2208 // Have to add jmethod_ids() to class loader data thread-safely.
2209 // Also have to add the method to the list safely, which the cld lock
2210 // protects as well.
2211 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2212 if (cld->jmethod_ids() == NULL) {
2213 cld->set_jmethod_ids(new JNIMethodBlock());
2214 }
2215 // jmethodID is a pointer to Method*
2216 return (jmethodID)cld->jmethod_ids()->add_method(m);
2217 } else {
2218 // At safepoint, we are single threaded and can set this.
2219 if (cld->jmethod_ids() == NULL) {
2220 cld->set_jmethod_ids(new JNIMethodBlock());
2221 }
2222 // jmethodID is a pointer to Method*
2223 return (jmethodID)cld->jmethod_ids()->add_method(m);
2224 }
2225 }
2226
2227 jmethodID Method::jmethod_id() {
2228 methodHandle mh(Thread::current(), this);
2229 return method_holder()->get_jmethod_id(mh);
2230 }
2231
2232 // Mark a jmethodID as free. This is called when there is a data race in
2233 // InstanceKlass while creating the jmethodID cache.
2234 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2235 ClassLoaderData* cld = loader_data;
2236 Method** ptr = (Method**)m;
2237 assert(cld->jmethod_ids() != NULL, "should have method handles");
2238 cld->jmethod_ids()->destroy_method(ptr);
2239 }
2240
2241 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2242 // Can't assert the method_holder is the same because the new method has the
2243 // scratch method holder.
2244 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2245 == new_method->method_holder()->class_loader() ||
2246 new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2247 "changing to a different class loader");
2248 // Just change the method in place, jmethodID pointer doesn't change.
2249 *((Method**)jmid) = new_method;
2250 }
2251
2252 bool Method::is_method_id(jmethodID mid) {
2253 Method* m = resolve_jmethod_id(mid);
2254 assert(m != NULL, "should be called with non-null method");
2255 InstanceKlass* ik = m->method_holder();
2256 ClassLoaderData* cld = ik->class_loader_data();
2257 if (cld->jmethod_ids() == NULL) return false;
2258 return (cld->jmethod_ids()->contains((Method**)mid));
2259 }
2260
2261 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2262 if (mid == NULL) return NULL;
2263 Method* o = resolve_jmethod_id(mid);
2264 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2265 return NULL;
2266 }
2267 return o;
2268 };
2269
2270 void Method::set_on_stack(const bool value) {
2271 // Set both the method itself and its constant pool. The constant pool
2272 // on stack means some method referring to it is also on the stack.
2273 constants()->set_on_stack(value);
2274
2275 bool already_set = on_stack();
2276 _access_flags.set_on_stack(value);
2277 if (value && !already_set) {
2278 MetadataOnStackMark::record(this);
2279 }
2280 assert(!value || !is_old() || is_obsolete() || is_running_emcp(),
2281 "emcp methods cannot run after emcp bit is cleared");
2282 }
2283
2284 // Called when the class loader is unloaded to make all methods weak.
2285 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2286 loader_data->jmethod_ids()->clear_all_methods();
2287 }
2288
2289 bool Method::has_method_vptr(const void* ptr) {
2290 Method m;
2291 // This assumes that the vtbl pointer is the first word of a C++ object.
2292 return dereference_vptr(&m) == dereference_vptr(ptr);
2293 }
2294
2295 // Check that this pointer is valid by checking that the vtbl pointer matches
2296 bool Method::is_valid_method(const Method* m) {
2297 if (m == NULL) {
2298 return false;
2299 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2300 // Quick sanity check on pointer.
2301 return false;
2302 } else if (m->is_shared()) {
2303 return MetaspaceShared::is_valid_shared_method(m);
2304 } else if (Metaspace::contains_non_shared(m)) {
2305 return has_method_vptr((const void*)m);
2306 } else {
2307 return false;
2308 }
2309 }
2310
2311 #ifndef PRODUCT
2312 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2313 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2314 }
2315 #endif // PRODUCT
2316
2317
2318 // Printing
2319
2320 #ifndef PRODUCT
2321
2322 void Method::print_on(outputStream* st) const {
2323 ResourceMark rm;
2324 assert(is_method(), "must be method");
2325 st->print_cr("%s", internal_name());
2326 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2327 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2328 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2329 constants()->print_value_on(st); st->cr();
2330 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2331 st->print (" - name: "); name()->print_value_on(st); st->cr();
2332 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2333 st->print_cr(" - max stack: %d", max_stack());
2334 st->print_cr(" - max locals: %d", max_locals());
2335 st->print_cr(" - size of params: %d", size_of_parameters());
2336 st->print_cr(" - method size: %d", method_size());
2337 if (intrinsic_id() != vmIntrinsics::_none)
2338 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2339 if (highest_comp_level() != CompLevel_none)
2340 st->print_cr(" - highest level: %d", highest_comp_level());
2341 st->print_cr(" - vtable index: %d", _vtable_index);
2342 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2343 st->print( " - adapters: ");
2344 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2345 if (a == NULL)
2346 st->print_cr(INTPTR_FORMAT, p2i(a));
2347 else
2348 a->print_adapter_on(st);
2349 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2350 st->print_cr(" - code size: %d", code_size());
2351 if (code_size() != 0) {
2352 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2353 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2354 }
2355 if (method_data() != NULL) {
2356 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2357 }
2358 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2359 if (checked_exceptions_length() > 0) {
2360 CheckedExceptionElement* table = checked_exceptions_start();
2361 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2362 if (Verbose) {
2363 for (int i = 0; i < checked_exceptions_length(); i++) {
2364 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2365 }
2366 }
2367 }
2368 if (has_linenumber_table()) {
2369 u_char* table = compressed_linenumber_table();
2370 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2371 if (Verbose) {
2372 CompressedLineNumberReadStream stream(table);
2373 while (stream.read_pair()) {
2374 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2375 }
2376 }
2377 }
2378 st->print_cr(" - localvar length: %d", localvariable_table_length());
2379 if (localvariable_table_length() > 0) {
2380 LocalVariableTableElement* table = localvariable_table_start();
2381 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2382 if (Verbose) {
2383 for (int i = 0; i < localvariable_table_length(); i++) {
2384 int bci = table[i].start_bci;
2385 int len = table[i].length;
2386 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2387 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2388 int slot = table[i].slot;
2389 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2390 }
2391 }
2392 }
2393 if (code() != NULL) {
2394 st->print (" - compiled code: ");
2395 code()->print_value_on(st);
2396 }
2397 if (is_native()) {
2398 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2399 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2400 }
2401 }
2402
2403 void Method::print_linkage_flags(outputStream* st) {
2404 access_flags().print_on(st);
2405 if (is_default_method()) {
2406 st->print("default ");
2407 }
2408 if (is_overpass()) {
2409 st->print("overpass ");
2410 }
2411 }
2412 #endif //PRODUCT
2413
2414 void Method::print_value_on(outputStream* st) const {
2415 assert(is_method(), "must be method");
2416 st->print("%s", internal_name());
2417 print_address_on(st);
2418 st->print(" ");
2419 name()->print_value_on(st);
2420 st->print(" ");
2421 signature()->print_value_on(st);
2422 st->print(" in ");
2423 method_holder()->print_value_on(st);
2424 if (WizardMode) st->print("#%d", _vtable_index);
2425 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2426 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2427 }
2428
2429 #if INCLUDE_SERVICES
2430 // Size Statistics
2431 void Method::collect_statistics(KlassSizeStats *sz) const {
2432 int mysize = sz->count(this);
2433 sz->_method_bytes += mysize;
2434 sz->_method_all_bytes += mysize;
2435 sz->_rw_bytes += mysize;
2436
2437 if (constMethod()) {
2438 constMethod()->collect_statistics(sz);
2439 }
2440 if (method_data()) {
2441 method_data()->collect_statistics(sz);
2442 }
2443 }
2444 #endif // INCLUDE_SERVICES
2445
2446 // LogTouchedMethods and PrintTouchedMethods
2447
2448 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2449 // the Method may be garbage collected. Let's roll our own hash table.
2450 class TouchedMethodRecord : CHeapObj<mtTracing> {
2451 public:
2452 // It's OK to store Symbols here because they will NOT be GC'ed if
2453 // LogTouchedMethods is enabled.
2454 TouchedMethodRecord* _next;
2455 Symbol* _class_name;
2456 Symbol* _method_name;
2457 Symbol* _method_signature;
2458 };
2459
2460 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2461 static TouchedMethodRecord** _touched_method_table = NULL;
2462
2463 void Method::log_touched(TRAPS) {
2464
2465 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2466 Symbol* my_class = klass_name();
2467 Symbol* my_name = name();
2468 Symbol* my_sig = signature();
2469
2470 unsigned int hash = my_class->identity_hash() +
2471 my_name->identity_hash() +
2472 my_sig->identity_hash();
2473 juint index = juint(hash) % table_size;
2474
2475 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2476 if (_touched_method_table == NULL) {
2477 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2478 mtTracing, CURRENT_PC);
2479 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2480 }
2481
2482 TouchedMethodRecord* ptr = _touched_method_table[index];
2483 while (ptr) {
2484 if (ptr->_class_name == my_class &&
2485 ptr->_method_name == my_name &&
2486 ptr->_method_signature == my_sig) {
2487 return;
2488 }
2489 if (ptr->_next == NULL) break;
2490 ptr = ptr->_next;
2491 }
2492 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2493 my_class->increment_refcount();
2494 my_name->increment_refcount();
2495 my_sig->increment_refcount();
2496 nptr->_class_name = my_class;
2497 nptr->_method_name = my_name;
2498 nptr->_method_signature = my_sig;
2499 nptr->_next = NULL;
2500
2501 if (ptr == NULL) {
2502 // first
2503 _touched_method_table[index] = nptr;
2504 } else {
2505 ptr->_next = nptr;
2506 }
2507 }
2508
2509 void Method::print_touched_methods(outputStream* out) {
2510 MutexLocker ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2511 out->print_cr("# Method::print_touched_methods version 1");
2512 if (_touched_method_table) {
2513 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2514 TouchedMethodRecord* ptr = _touched_method_table[i];
2515 while(ptr) {
2516 ptr->_class_name->print_symbol_on(out); out->print(".");
2517 ptr->_method_name->print_symbol_on(out); out->print(":");
2518 ptr->_method_signature->print_symbol_on(out); out->cr();
2519 ptr = ptr->_next;
2520 }
2521 }
2522 }
2523 }
2524
2525 // Verification
2526
2527 void Method::verify_on(outputStream* st) {
2528 guarantee(is_method(), "object must be method");
2529 guarantee(constants()->is_constantPool(), "should be constant pool");
2530 MethodData* md = method_data();
2531 guarantee(md == NULL ||
2532 md->is_methodData(), "should be method data");
2533 }