1 /*
2 * Copyright (c) 1997, 2021, 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 "cds/cppVtables.hpp"
27 #include "cds/metaspaceShared.hpp"
28 #include "classfile/classLoaderDataGraph.hpp"
29 #include "classfile/metadataOnStackMark.hpp"
30 #include "classfile/symbolTable.hpp"
31 #include "classfile/systemDictionary.hpp"
32 #include "classfile/vmClasses.hpp"
33 #include "code/codeCache.hpp"
34 #include "code/debugInfoRec.hpp"
35 #include "compiler/compilationPolicy.hpp"
36 #include "gc/shared/collectedHeap.inline.hpp"
37 #include "interpreter/bytecodeStream.hpp"
38 #include "interpreter/bytecodeTracer.hpp"
39 #include "interpreter/bytecodes.hpp"
40 #include "interpreter/interpreter.hpp"
41 #include "interpreter/oopMapCache.hpp"
42 #include "logging/log.hpp"
43 #include "logging/logTag.hpp"
44 #include "logging/logStream.hpp"
45 #include "memory/allocation.inline.hpp"
46 #include "memory/metadataFactory.hpp"
47 #include "memory/metaspaceClosure.hpp"
48 #include "memory/oopFactory.hpp"
49 #include "memory/resourceArea.hpp"
50 #include "memory/universe.hpp"
51 #include "oops/constMethod.hpp"
52 #include "oops/constantPool.hpp"
53 #include "oops/klass.inline.hpp"
54 #include "oops/method.inline.hpp"
55 #include "oops/methodData.hpp"
56 #include "oops/objArrayKlass.hpp"
57 #include "oops/objArrayOop.inline.hpp"
58 #include "oops/oop.inline.hpp"
59 #include "oops/symbol.hpp"
60 #include "prims/jvmtiExport.hpp"
61 #include "prims/methodHandles.hpp"
62 #include "runtime/arguments.hpp"
63 #include "runtime/atomic.hpp"
64 #include "runtime/frame.inline.hpp"
65 #include "runtime/handles.inline.hpp"
66 #include "runtime/init.hpp"
67 #include "runtime/orderAccess.hpp"
68 #include "runtime/relocator.hpp"
69 #include "runtime/safepointVerifiers.hpp"
70 #include "runtime/sharedRuntime.hpp"
71 #include "runtime/signature.hpp"
72 #include "runtime/vm_version.hpp"
73 #include "services/memTracker.hpp"
74 #include "utilities/align.hpp"
75 #include "utilities/quickSort.hpp"
76 #include "utilities/vmError.hpp"
77 #include "utilities/xmlstream.hpp"
78
79 // Implementation of Method
80
allocate(ClassLoaderData * loader_data,int byte_code_size,AccessFlags access_flags,InlineTableSizes * sizes,ConstMethod::MethodType method_type,TRAPS)81 Method* Method::allocate(ClassLoaderData* loader_data,
82 int byte_code_size,
83 AccessFlags access_flags,
84 InlineTableSizes* sizes,
85 ConstMethod::MethodType method_type,
86 TRAPS) {
87 assert(!access_flags.is_native() || byte_code_size == 0,
88 "native methods should not contain byte codes");
89 ConstMethod* cm = ConstMethod::allocate(loader_data,
90 byte_code_size,
91 sizes,
92 method_type,
93 CHECK_NULL);
94 int size = Method::size(access_flags.is_native());
95 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
96 }
97
Method(ConstMethod * xconst,AccessFlags access_flags)98 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
99 NoSafepointVerifier no_safepoint;
100 set_constMethod(xconst);
101 set_access_flags(access_flags);
102 set_intrinsic_id(vmIntrinsics::_none);
103 set_force_inline(false);
104 set_hidden(false);
105 set_dont_inline(false);
106 set_has_injected_profile(false);
107 set_method_data(NULL);
108 clear_method_counters();
109 set_vtable_index(Method::garbage_vtable_index);
110
111 // Fix and bury in Method*
112 set_interpreter_entry(NULL); // sets i2i entry and from_int
113 set_adapter_entry(NULL);
114 Method::clear_code(); // from_c/from_i get set to c2i/i2i
115
116 if (access_flags.is_native()) {
117 clear_native_function();
118 set_signature_handler(NULL);
119 }
120
121 NOT_PRODUCT(set_compiled_invocation_count(0);)
122 }
123
124 // Release Method*. The nmethod will be gone when we get here because
125 // we've walked the code cache.
deallocate_contents(ClassLoaderData * loader_data)126 void Method::deallocate_contents(ClassLoaderData* loader_data) {
127 MetadataFactory::free_metadata(loader_data, constMethod());
128 set_constMethod(NULL);
129 MetadataFactory::free_metadata(loader_data, method_data());
130 set_method_data(NULL);
131 MetadataFactory::free_metadata(loader_data, method_counters());
132 clear_method_counters();
133 // The nmethod will be gone when we get here.
134 if (code() != NULL) _code = NULL;
135 }
136
release_C_heap_structures()137 void Method::release_C_heap_structures() {
138 if (method_data()) {
139 #if INCLUDE_JVMCI
140 FailedSpeculation::free_failed_speculations(method_data()->get_failed_speculations_address());
141 #endif
142 // Destroy MethodData
143 method_data()->~MethodData();
144 }
145 }
146
get_i2c_entry()147 address Method::get_i2c_entry() {
148 assert(adapter() != NULL, "must have");
149 return adapter()->get_i2c_entry();
150 }
151
get_c2i_entry()152 address Method::get_c2i_entry() {
153 assert(adapter() != NULL, "must have");
154 return adapter()->get_c2i_entry();
155 }
156
get_c2i_unverified_entry()157 address Method::get_c2i_unverified_entry() {
158 assert(adapter() != NULL, "must have");
159 return adapter()->get_c2i_unverified_entry();
160 }
161
get_c2i_no_clinit_check_entry()162 address Method::get_c2i_no_clinit_check_entry() {
163 assert(VM_Version::supports_fast_class_init_checks(), "");
164 assert(adapter() != NULL, "must have");
165 return adapter()->get_c2i_no_clinit_check_entry();
166 }
167
name_and_sig_as_C_string() const168 char* Method::name_and_sig_as_C_string() const {
169 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
170 }
171
name_and_sig_as_C_string(char * buf,int size) const172 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
173 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
174 }
175
name_and_sig_as_C_string(Klass * klass,Symbol * method_name,Symbol * signature)176 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
177 const char* klass_name = klass->external_name();
178 int klass_name_len = (int)strlen(klass_name);
179 int method_name_len = method_name->utf8_length();
180 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
181 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
182 strcpy(dest, klass_name);
183 dest[klass_name_len] = '.';
184 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
185 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
186 dest[len] = 0;
187 return dest;
188 }
189
name_and_sig_as_C_string(Klass * klass,Symbol * method_name,Symbol * signature,char * buf,int size)190 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
191 Symbol* klass_name = klass->name();
192 klass_name->as_klass_external_name(buf, size);
193 int len = (int)strlen(buf);
194
195 if (len < size - 1) {
196 buf[len++] = '.';
197
198 method_name->as_C_string(&(buf[len]), size - len);
199 len = (int)strlen(buf);
200
201 signature->as_C_string(&(buf[len]), size - len);
202 }
203
204 return buf;
205 }
206
external_name() const207 const char* Method::external_name() const {
208 return external_name(constants()->pool_holder(), name(), signature());
209 }
210
print_external_name(outputStream * os) const211 void Method::print_external_name(outputStream *os) const {
212 print_external_name(os, constants()->pool_holder(), name(), signature());
213 }
214
external_name(Klass * klass,Symbol * method_name,Symbol * signature)215 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
216 stringStream ss;
217 print_external_name(&ss, klass, method_name, signature);
218 return ss.as_string();
219 }
220
print_external_name(outputStream * os,Klass * klass,Symbol * method_name,Symbol * signature)221 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
222 signature->print_as_signature_external_return_type(os);
223 os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
224 signature->print_as_signature_external_parameters(os);
225 os->print(")");
226 }
227
fast_exception_handler_bci_for(const methodHandle & mh,Klass * ex_klass,int throw_bci,TRAPS)228 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
229 if (log_is_enabled(Debug, exceptions)) {
230 ResourceMark rm(THREAD);
231 log_debug(exceptions)("Looking for catch handler for exception of type \"%s\" in method \"%s\"",
232 ex_klass == NULL ? "NULL" : ex_klass->external_name(), mh->name()->as_C_string());
233 }
234 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
235 // access exception table
236 ExceptionTable table(mh());
237 int length = table.length();
238 // iterate through all entries sequentially
239 constantPoolHandle pool(THREAD, mh->constants());
240 for (int i = 0; i < length; i ++) {
241 //reacquire the table in case a GC happened
242 ExceptionTable table(mh());
243 int beg_bci = table.start_pc(i);
244 int end_bci = table.end_pc(i);
245 assert(beg_bci <= end_bci, "inconsistent exception table");
246 log_debug(exceptions)(" - checking exception table entry for BCI %d to %d",
247 beg_bci, end_bci);
248
249 if (beg_bci <= throw_bci && throw_bci < end_bci) {
250 // exception handler bci range covers throw_bci => investigate further
251 log_debug(exceptions)(" - entry covers throw point BCI %d", throw_bci);
252
253 int handler_bci = table.handler_pc(i);
254 int klass_index = table.catch_type_index(i);
255 if (klass_index == 0) {
256 if (log_is_enabled(Info, exceptions)) {
257 ResourceMark rm(THREAD);
258 log_info(exceptions)("Found catch-all handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
259 ex_klass == NULL ? "NULL" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
260 }
261 return handler_bci;
262 } else if (ex_klass == NULL) {
263 // Is this even possible?
264 if (log_is_enabled(Info, exceptions)) {
265 ResourceMark rm(THREAD);
266 log_info(exceptions)("NULL exception class is implicitly caught by handler in method \"%s\" at BCI: %d",
267 mh()->name()->as_C_string(), handler_bci);
268 }
269 return handler_bci;
270 } else {
271 if (log_is_enabled(Debug, exceptions)) {
272 ResourceMark rm(THREAD);
273 log_debug(exceptions)(" - resolving catch type \"%s\"",
274 pool->klass_name_at(klass_index)->as_C_string());
275 }
276 // we know the exception class => get the constraint class
277 // this may require loading of the constraint class; if verification
278 // fails or some other exception occurs, return handler_bci
279 Klass* k = pool->klass_at(klass_index, THREAD);
280 if (HAS_PENDING_EXCEPTION) {
281 if (log_is_enabled(Debug, exceptions)) {
282 ResourceMark rm(THREAD);
283 log_debug(exceptions)(" - exception \"%s\" occurred resolving catch type",
284 PENDING_EXCEPTION->klass()->external_name());
285 }
286 return handler_bci;
287 }
288 assert(k != NULL, "klass not loaded");
289 if (ex_klass->is_subtype_of(k)) {
290 if (log_is_enabled(Info, exceptions)) {
291 ResourceMark rm(THREAD);
292 log_info(exceptions)("Found matching handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
293 ex_klass == NULL ? "NULL" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
294 }
295 return handler_bci;
296 }
297 }
298 }
299 }
300
301 if (log_is_enabled(Debug, exceptions)) {
302 ResourceMark rm(THREAD);
303 log_debug(exceptions)("No catch handler found for exception of type \"%s\" in method \"%s\"",
304 ex_klass->external_name(), mh->name()->as_C_string());
305 }
306
307 return -1;
308 }
309
mask_for(int bci,InterpreterOopMap * mask)310 void Method::mask_for(int bci, InterpreterOopMap* mask) {
311 methodHandle h_this(Thread::current(), this);
312 // Only GC uses the OopMapCache during thread stack root scanning
313 // any other uses generate an oopmap but do not save it in the cache.
314 if (Universe::heap()->is_gc_active()) {
315 method_holder()->mask_for(h_this, bci, mask);
316 } else {
317 OopMapCache::compute_one_oop_map(h_this, bci, mask);
318 }
319 return;
320 }
321
322
bci_from(address bcp) const323 int Method::bci_from(address bcp) const {
324 if (is_native() && bcp == 0) {
325 return 0;
326 }
327 #ifdef ASSERT
328 {
329 ResourceMark rm;
330 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
331 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
332 p2i(bcp), name_and_sig_as_C_string());
333 }
334 #endif
335 return bcp - code_base();
336 }
337
338
validate_bci(int bci) const339 int Method::validate_bci(int bci) const {
340 return (bci == 0 || bci < code_size()) ? bci : -1;
341 }
342
343 // Return bci if it appears to be a valid bcp
344 // Return -1 otherwise.
345 // Used by profiling code, when invalid data is a possibility.
346 // The caller is responsible for validating the Method* itself.
validate_bci_from_bcp(address bcp) const347 int Method::validate_bci_from_bcp(address bcp) const {
348 // keep bci as -1 if not a valid bci
349 int bci = -1;
350 if (bcp == 0 || bcp == code_base()) {
351 // code_size() may return 0 and we allow 0 here
352 // the method may be native
353 bci = 0;
354 } else if (contains(bcp)) {
355 bci = bcp - code_base();
356 }
357 // Assert that if we have dodged any asserts, bci is negative.
358 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
359 return bci;
360 }
361
bcp_from(int bci) const362 address Method::bcp_from(int bci) const {
363 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
364 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
365 address bcp = code_base() + bci;
366 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
367 return bcp;
368 }
369
bcp_from(address bcp) const370 address Method::bcp_from(address bcp) const {
371 if (is_native() && bcp == NULL) {
372 return code_base();
373 } else {
374 return bcp;
375 }
376 }
377
size(bool is_native)378 int Method::size(bool is_native) {
379 // If native, then include pointers for native_function and signature_handler
380 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
381 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
382 return align_metadata_size(header_size() + extra_words);
383 }
384
klass_name() const385 Symbol* Method::klass_name() const {
386 return method_holder()->name();
387 }
388
metaspace_pointers_do(MetaspaceClosure * it)389 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
390 log_trace(cds)("Iter(Method): %p", this);
391
392 if (!method_holder()->is_rewritten()) {
393 it->push(&_constMethod, MetaspaceClosure::_writable);
394 } else {
395 it->push(&_constMethod);
396 }
397 it->push(&_method_data);
398 it->push(&_method_counters);
399 }
400
401 // Attempt to return method to original state. Clear any pointers
402 // (to objects outside the shared spaces). We won't be able to predict
403 // where they should point in a new JVM. Further initialize some
404 // entries now in order allow them to be write protected later.
405
remove_unshareable_info()406 void Method::remove_unshareable_info() {
407 unlink_method();
408 JFR_ONLY(REMOVE_METHOD_ID(this);)
409 }
410
set_vtable_index(int index)411 void Method::set_vtable_index(int index) {
412 if (is_shared() && !MetaspaceShared::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
413 // At runtime initialize_vtable is rerun as part of link_class_impl()
414 // for a shared class loaded by the non-boot loader to obtain the loader
415 // constraints based on the runtime classloaders' context.
416 return; // don't write into the shared class
417 } else {
418 _vtable_index = index;
419 }
420 }
421
set_itable_index(int index)422 void Method::set_itable_index(int index) {
423 if (is_shared() && !MetaspaceShared::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
424 // At runtime initialize_itable is rerun as part of link_class_impl()
425 // for a shared class loaded by the non-boot loader to obtain the loader
426 // constraints based on the runtime classloaders' context. The dumptime
427 // itable index should be the same as the runtime index.
428 assert(_vtable_index == itable_index_max - index,
429 "archived itable index is different from runtime index");
430 return; // don’t write into the shared class
431 } else {
432 _vtable_index = itable_index_max - index;
433 }
434 assert(valid_itable_index(), "");
435 }
436
437 // The RegisterNatives call being attempted tried to register with a method that
438 // is not native. Ask JVM TI what prefixes have been specified. Then check
439 // to see if the native method is now wrapped with the prefixes. See the
440 // SetNativeMethodPrefix(es) functions in the JVM TI Spec for details.
find_prefixed_native(Klass * k,Symbol * name,Symbol * signature,TRAPS)441 static Method* find_prefixed_native(Klass* k, Symbol* name, Symbol* signature, TRAPS) {
442 #if INCLUDE_JVMTI
443 ResourceMark rm(THREAD);
444 Method* method;
445 int name_len = name->utf8_length();
446 char* name_str = name->as_utf8();
447 int prefix_count;
448 char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
449 for (int i = 0; i < prefix_count; i++) {
450 char* prefix = prefixes[i];
451 int prefix_len = (int)strlen(prefix);
452
453 // try adding this prefix to the method name and see if it matches another method name
454 int trial_len = name_len + prefix_len;
455 char* trial_name_str = NEW_RESOURCE_ARRAY(char, trial_len + 1);
456 strcpy(trial_name_str, prefix);
457 strcat(trial_name_str, name_str);
458 TempNewSymbol trial_name = SymbolTable::probe(trial_name_str, trial_len);
459 if (trial_name == NULL) {
460 continue; // no such symbol, so this prefix wasn't used, try the next prefix
461 }
462 method = k->lookup_method(trial_name, signature);
463 if (method == NULL) {
464 continue; // signature doesn't match, try the next prefix
465 }
466 if (method->is_native()) {
467 method->set_is_prefixed_native();
468 return method; // wahoo, we found a prefixed version of the method, return it
469 }
470 // found as non-native, so prefix is good, add it, probably just need more prefixes
471 name_len = trial_len;
472 name_str = trial_name_str;
473 }
474 #endif // INCLUDE_JVMTI
475 return NULL; // not found
476 }
477
register_native(Klass * k,Symbol * name,Symbol * signature,address entry,TRAPS)478 bool Method::register_native(Klass* k, Symbol* name, Symbol* signature, address entry, TRAPS) {
479 Method* method = k->lookup_method(name, signature);
480 if (method == NULL) {
481 ResourceMark rm(THREAD);
482 stringStream st;
483 st.print("Method '");
484 print_external_name(&st, k, name, signature);
485 st.print("' name or signature does not match");
486 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
487 }
488 if (!method->is_native()) {
489 // trying to register to a non-native method, see if a JVM TI agent has added prefix(es)
490 method = find_prefixed_native(k, name, signature, THREAD);
491 if (method == NULL) {
492 ResourceMark rm(THREAD);
493 stringStream st;
494 st.print("Method '");
495 print_external_name(&st, k, name, signature);
496 st.print("' is not declared as native");
497 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
498 }
499 }
500
501 if (entry != NULL) {
502 method->set_native_function(entry, native_bind_event_is_interesting);
503 } else {
504 method->clear_native_function();
505 }
506 if (log_is_enabled(Debug, jni, resolve)) {
507 ResourceMark rm(THREAD);
508 log_debug(jni, resolve)("[Registering JNI native method %s.%s]",
509 method->method_holder()->external_name(),
510 method->name()->as_C_string());
511 }
512 return true;
513 }
514
was_executed_more_than(int n)515 bool Method::was_executed_more_than(int n) {
516 // Invocation counter is reset when the Method* is compiled.
517 // If the method has compiled code we therefore assume it has
518 // be excuted more than n times.
519 if (is_accessor() || is_empty_method() || (code() != NULL)) {
520 // interpreter doesn't bump invocation counter of trivial methods
521 // compiler does not bump invocation counter of compiled methods
522 return true;
523 }
524 else if ((method_counters() != NULL &&
525 method_counters()->invocation_counter()->carry()) ||
526 (method_data() != NULL &&
527 method_data()->invocation_counter()->carry())) {
528 // The carry bit is set when the counter overflows and causes
529 // a compilation to occur. We don't know how many times
530 // the counter has been reset, so we simply assume it has
531 // been executed more than n times.
532 return true;
533 } else {
534 return invocation_count() > n;
535 }
536 }
537
print_invocation_count()538 void Method::print_invocation_count() {
539 //---< compose+print method return type, klass, name, and signature >---
540 if (is_static()) tty->print("static ");
541 if (is_final()) tty->print("final ");
542 if (is_synchronized()) tty->print("synchronized ");
543 if (is_native()) tty->print("native ");
544 tty->print("%s::", method_holder()->external_name());
545 name()->print_symbol_on(tty);
546 signature()->print_symbol_on(tty);
547
548 if (WizardMode) {
549 // dump the size of the byte codes
550 tty->print(" {%d}", code_size());
551 }
552 tty->cr();
553
554 // Counting based on signed int counters tends to overflow with
555 // longer-running workloads on fast machines. The counters under
556 // consideration here, however, are limited in range by counting
557 // logic. See InvocationCounter:count_limit for example.
558 // No "overflow precautions" need to be implemented here.
559 tty->print_cr (" interpreter_invocation_count: " INT32_FORMAT_W(11), interpreter_invocation_count());
560 tty->print_cr (" invocation_counter: " INT32_FORMAT_W(11), invocation_count());
561 tty->print_cr (" backedge_counter: " INT32_FORMAT_W(11), backedge_count());
562
563 if (method_data() != NULL) {
564 tty->print_cr (" decompile_count: " UINT32_FORMAT_W(11), method_data()->decompile_count());
565 }
566
567 #ifndef PRODUCT
568 if (CountCompiledCalls) {
569 tty->print_cr (" compiled_invocation_count: " INT64_FORMAT_W(11), compiled_invocation_count());
570 }
571 #endif
572 }
573
574 // Build a MethodData* object to hold information about this method
575 // collected in the interpreter.
build_interpreter_method_data(const methodHandle & method,TRAPS)576 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
577 // Do not profile the method if metaspace has hit an OOM previously
578 // allocating profiling data. Callers clear pending exception so don't
579 // add one here.
580 if (ClassLoaderDataGraph::has_metaspace_oom()) {
581 return;
582 }
583
584 // Grab a lock here to prevent multiple
585 // MethodData*s from being created.
586 MutexLocker ml(THREAD, MethodData_lock);
587 if (method->method_data() == NULL) {
588 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
589 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
590 if (HAS_PENDING_EXCEPTION) {
591 CompileBroker::log_metaspace_failure();
592 ClassLoaderDataGraph::set_metaspace_oom(true);
593 return; // return the exception (which is cleared)
594 }
595
596 method->set_method_data(method_data);
597 if (PrintMethodData && (Verbose || WizardMode)) {
598 ResourceMark rm(THREAD);
599 tty->print("build_interpreter_method_data for ");
600 method->print_name(tty);
601 tty->cr();
602 // At the end of the run, the MDO, full of data, will be dumped.
603 }
604 }
605 }
606
build_method_counters(Thread * current,Method * m)607 MethodCounters* Method::build_method_counters(Thread* current, Method* m) {
608 // Do not profile the method if metaspace has hit an OOM previously
609 if (ClassLoaderDataGraph::has_metaspace_oom()) {
610 return NULL;
611 }
612
613 methodHandle mh(current, m);
614 MethodCounters* counters;
615 if (current->is_Java_thread()) {
616 JavaThread* THREAD = current->as_Java_thread(); // For exception macros.
617 // Use the TRAPS version for a JavaThread so it will adjust the GC threshold
618 // if needed.
619 counters = MethodCounters::allocate_with_exception(mh, THREAD);
620 if (HAS_PENDING_EXCEPTION) {
621 CLEAR_PENDING_EXCEPTION;
622 }
623 } else {
624 // Call metaspace allocation that doesn't throw exception if the
625 // current thread isn't a JavaThread, ie. the VMThread.
626 counters = MethodCounters::allocate_no_exception(mh);
627 }
628
629 if (counters == NULL) {
630 CompileBroker::log_metaspace_failure();
631 ClassLoaderDataGraph::set_metaspace_oom(true);
632 return NULL;
633 }
634
635 if (!mh->init_method_counters(counters)) {
636 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
637 }
638
639 if (LogTouchedMethods) {
640 mh->log_touched(current);
641 }
642
643 return mh->method_counters();
644 }
645
init_method_counters(MethodCounters * counters)646 bool Method::init_method_counters(MethodCounters* counters) {
647 // Try to install a pointer to MethodCounters, return true on success.
648 return Atomic::replace_if_null(&_method_counters, counters);
649 }
650
extra_stack_words()651 int Method::extra_stack_words() {
652 // not an inline function, to avoid a header dependency on Interpreter
653 return extra_stack_entries() * Interpreter::stackElementSize;
654 }
655
656 // Derive size of parameters, return type, and fingerprint,
657 // all in one pass, which is run at load time.
658 // We need the first two, and might as well grab the third.
compute_from_signature(Symbol * sig)659 void Method::compute_from_signature(Symbol* sig) {
660 // At this point, since we are scanning the signature,
661 // we might as well compute the whole fingerprint.
662 Fingerprinter fp(sig, is_static());
663 set_size_of_parameters(fp.size_of_parameters());
664 constMethod()->set_result_type(fp.return_type());
665 constMethod()->set_fingerprint(fp.fingerprint());
666 }
667
is_vanilla_constructor() const668 bool Method::is_vanilla_constructor() const {
669 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
670 // which only calls the superclass vanilla constructor and possibly does stores of
671 // zero constants to local fields:
672 //
673 // aload_0
674 // invokespecial
675 // indexbyte1
676 // indexbyte2
677 //
678 // followed by an (optional) sequence of:
679 //
680 // aload_0
681 // aconst_null / iconst_0 / fconst_0 / dconst_0
682 // putfield
683 // indexbyte1
684 // indexbyte2
685 //
686 // followed by:
687 //
688 // return
689
690 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
691 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
692 int size = code_size();
693 // Check if size match
694 if (size == 0 || size % 5 != 0) return false;
695 address cb = code_base();
696 int last = size - 1;
697 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
698 // Does not call superclass default constructor
699 return false;
700 }
701 // Check optional sequence
702 for (int i = 4; i < last; i += 5) {
703 if (cb[i] != Bytecodes::_aload_0) return false;
704 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
705 if (cb[i+2] != Bytecodes::_putfield) return false;
706 }
707 return true;
708 }
709
710
compute_has_loops_flag()711 bool Method::compute_has_loops_flag() {
712 BytecodeStream bcs(methodHandle(Thread::current(), this));
713 Bytecodes::Code bc;
714
715 while ((bc = bcs.next()) >= 0) {
716 switch (bc) {
717 case Bytecodes::_ifeq:
718 case Bytecodes::_ifnull:
719 case Bytecodes::_iflt:
720 case Bytecodes::_ifle:
721 case Bytecodes::_ifne:
722 case Bytecodes::_ifnonnull:
723 case Bytecodes::_ifgt:
724 case Bytecodes::_ifge:
725 case Bytecodes::_if_icmpeq:
726 case Bytecodes::_if_icmpne:
727 case Bytecodes::_if_icmplt:
728 case Bytecodes::_if_icmpgt:
729 case Bytecodes::_if_icmple:
730 case Bytecodes::_if_icmpge:
731 case Bytecodes::_if_acmpeq:
732 case Bytecodes::_if_acmpne:
733 case Bytecodes::_goto:
734 case Bytecodes::_jsr:
735 if (bcs.dest() < bcs.next_bci()) _access_flags.set_has_loops();
736 break;
737
738 case Bytecodes::_goto_w:
739 case Bytecodes::_jsr_w:
740 if (bcs.dest_w() < bcs.next_bci()) _access_flags.set_has_loops();
741 break;
742
743 case Bytecodes::_lookupswitch: {
744 Bytecode_lookupswitch lookupswitch(this, bcs.bcp());
745 if (lookupswitch.default_offset() < 0) {
746 _access_flags.set_has_loops();
747 } else {
748 for (int i = 0; i < lookupswitch.number_of_pairs(); ++i) {
749 LookupswitchPair pair = lookupswitch.pair_at(i);
750 if (pair.offset() < 0) {
751 _access_flags.set_has_loops();
752 break;
753 }
754 }
755 }
756 break;
757 }
758 case Bytecodes::_tableswitch: {
759 Bytecode_tableswitch tableswitch(this, bcs.bcp());
760 if (tableswitch.default_offset() < 0) {
761 _access_flags.set_has_loops();
762 } else {
763 for (int i = 0; i < tableswitch.length(); ++i) {
764 if (tableswitch.dest_offset_at(i) < 0) {
765 _access_flags.set_has_loops();
766 }
767 }
768 }
769 break;
770 }
771 default:
772 break;
773 }
774 }
775 _access_flags.set_loops_flag_init();
776 return _access_flags.has_loops();
777 }
778
is_final_method(AccessFlags class_access_flags) const779 bool Method::is_final_method(AccessFlags class_access_flags) const {
780 // or "does_not_require_vtable_entry"
781 // default method or overpass can occur, is not final (reuses vtable entry)
782 // private methods in classes get vtable entries for backward class compatibility.
783 if (is_overpass() || is_default_method()) return false;
784 return is_final() || class_access_flags.is_final();
785 }
786
is_final_method() const787 bool Method::is_final_method() const {
788 return is_final_method(method_holder()->access_flags());
789 }
790
is_default_method() const791 bool Method::is_default_method() const {
792 if (method_holder() != NULL &&
793 method_holder()->is_interface() &&
794 !is_abstract() && !is_private()) {
795 return true;
796 } else {
797 return false;
798 }
799 }
800
can_be_statically_bound(AccessFlags class_access_flags) const801 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
802 if (is_final_method(class_access_flags)) return true;
803 #ifdef ASSERT
804 ResourceMark rm;
805 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
806 if (class_access_flags.is_interface()) {
807 assert(is_nonv == is_static() || is_nonv == is_private(),
808 "nonvirtual unexpected for non-static, non-private: %s",
809 name_and_sig_as_C_string());
810 }
811 #endif
812 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
813 return vtable_index() == nonvirtual_vtable_index;
814 }
815
can_be_statically_bound() const816 bool Method::can_be_statically_bound() const {
817 return can_be_statically_bound(method_holder()->access_flags());
818 }
819
can_be_statically_bound(InstanceKlass * context) const820 bool Method::can_be_statically_bound(InstanceKlass* context) const {
821 return (method_holder() == context) && can_be_statically_bound();
822 }
823
is_accessor() const824 bool Method::is_accessor() const {
825 return is_getter() || is_setter();
826 }
827
is_getter() const828 bool Method::is_getter() const {
829 if (code_size() != 5) return false;
830 if (size_of_parameters() != 1) return false;
831 if (java_code_at(0) != Bytecodes::_aload_0) return false;
832 if (java_code_at(1) != Bytecodes::_getfield) return false;
833 switch (java_code_at(4)) {
834 case Bytecodes::_ireturn:
835 case Bytecodes::_lreturn:
836 case Bytecodes::_freturn:
837 case Bytecodes::_dreturn:
838 case Bytecodes::_areturn:
839 break;
840 default:
841 return false;
842 }
843 return true;
844 }
845
is_setter() const846 bool Method::is_setter() const {
847 if (code_size() != 6) return false;
848 if (java_code_at(0) != Bytecodes::_aload_0) return false;
849 switch (java_code_at(1)) {
850 case Bytecodes::_iload_1:
851 case Bytecodes::_aload_1:
852 case Bytecodes::_fload_1:
853 if (size_of_parameters() != 2) return false;
854 break;
855 case Bytecodes::_dload_1:
856 case Bytecodes::_lload_1:
857 if (size_of_parameters() != 3) return false;
858 break;
859 default:
860 return false;
861 }
862 if (java_code_at(2) != Bytecodes::_putfield) return false;
863 if (java_code_at(5) != Bytecodes::_return) return false;
864 return true;
865 }
866
is_constant_getter() const867 bool Method::is_constant_getter() const {
868 int last_index = code_size() - 1;
869 // Check if the first 1-3 bytecodes are a constant push
870 // and the last bytecode is a return.
871 return (2 <= code_size() && code_size() <= 4 &&
872 Bytecodes::is_const(java_code_at(0)) &&
873 Bytecodes::length_for(java_code_at(0)) == last_index &&
874 Bytecodes::is_return(java_code_at(last_index)));
875 }
876
is_initializer() const877 bool Method::is_initializer() const {
878 return is_object_initializer() || is_static_initializer();
879 }
880
has_valid_initializer_flags() const881 bool Method::has_valid_initializer_flags() const {
882 return (is_static() ||
883 method_holder()->major_version() < 51);
884 }
885
is_static_initializer() const886 bool Method::is_static_initializer() const {
887 // For classfiles version 51 or greater, ensure that the clinit method is
888 // static. Non-static methods with the name "<clinit>" are not static
889 // initializers. (older classfiles exempted for backward compatibility)
890 return name() == vmSymbols::class_initializer_name() &&
891 has_valid_initializer_flags();
892 }
893
is_object_initializer() const894 bool Method::is_object_initializer() const {
895 return name() == vmSymbols::object_initializer_name();
896 }
897
needs_clinit_barrier() const898 bool Method::needs_clinit_barrier() const {
899 return is_static() && !method_holder()->is_initialized();
900 }
901
resolved_checked_exceptions_impl(Method * method,TRAPS)902 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
903 int length = method->checked_exceptions_length();
904 if (length == 0) { // common case
905 return objArrayHandle(THREAD, Universe::the_empty_class_array());
906 } else {
907 methodHandle h_this(THREAD, method);
908 objArrayOop m_oop = oopFactory::new_objArray(vmClasses::Class_klass(), length, CHECK_(objArrayHandle()));
909 objArrayHandle mirrors (THREAD, m_oop);
910 for (int i = 0; i < length; i++) {
911 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
912 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
913 if (log_is_enabled(Warning, exceptions) &&
914 !k->is_subclass_of(vmClasses::Throwable_klass())) {
915 ResourceMark rm(THREAD);
916 log_warning(exceptions)(
917 "Class %s in throws clause of method %s is not a subtype of class java.lang.Throwable",
918 k->external_name(), method->external_name());
919 }
920 mirrors->obj_at_put(i, k->java_mirror());
921 }
922 return mirrors;
923 }
924 };
925
926
line_number_from_bci(int bci) const927 int Method::line_number_from_bci(int bci) const {
928 int best_bci = 0;
929 int best_line = -1;
930 if (bci == SynchronizationEntryBCI) bci = 0;
931 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
932 // The line numbers are a short array of 2-tuples [start_pc, line_number].
933 // Not necessarily sorted and not necessarily one-to-one.
934 CompressedLineNumberReadStream stream(compressed_linenumber_table());
935 while (stream.read_pair()) {
936 if (stream.bci() == bci) {
937 // perfect match
938 return stream.line();
939 } else {
940 // update best_bci/line
941 if (stream.bci() < bci && stream.bci() >= best_bci) {
942 best_bci = stream.bci();
943 best_line = stream.line();
944 }
945 }
946 }
947 }
948 return best_line;
949 }
950
951
is_klass_loaded_by_klass_index(int klass_index) const952 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
953 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
954 Thread *thread = Thread::current();
955 Symbol* klass_name = constants()->klass_name_at(klass_index);
956 Handle loader(thread, method_holder()->class_loader());
957 Handle prot (thread, method_holder()->protection_domain());
958 return SystemDictionary::find_instance_klass(klass_name, loader, prot) != NULL;
959 } else {
960 return true;
961 }
962 }
963
964
is_klass_loaded(int refinfo_index,bool must_be_resolved) const965 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
966 int klass_index = constants()->klass_ref_index_at(refinfo_index);
967 if (must_be_resolved) {
968 // Make sure klass is resolved in constantpool.
969 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
970 }
971 return is_klass_loaded_by_klass_index(klass_index);
972 }
973
974
set_native_function(address function,bool post_event_flag)975 void Method::set_native_function(address function, bool post_event_flag) {
976 assert(function != NULL, "use clear_native_function to unregister natives");
977 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
978 address* native_function = native_function_addr();
979
980 // We can see racers trying to place the same native function into place. Once
981 // is plenty.
982 address current = *native_function;
983 if (current == function) return;
984 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
985 function != NULL) {
986 // native_method_throw_unsatisfied_link_error_entry() should only
987 // be passed when post_event_flag is false.
988 assert(function !=
989 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
990 "post_event_flag mis-match");
991
992 // post the bind event, and possible change the bind function
993 JvmtiExport::post_native_method_bind(this, &function);
994 }
995 *native_function = function;
996 // This function can be called more than once. We must make sure that we always
997 // use the latest registered method -> check if a stub already has been generated.
998 // If so, we have to make it not_entrant.
999 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
1000 if (nm != NULL) {
1001 nm->make_not_entrant();
1002 }
1003 }
1004
1005
has_native_function() const1006 bool Method::has_native_function() const {
1007 if (is_method_handle_intrinsic())
1008 return false; // special-cased in SharedRuntime::generate_native_wrapper
1009 address func = native_function();
1010 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
1011 }
1012
1013
clear_native_function()1014 void Method::clear_native_function() {
1015 // Note: is_method_handle_intrinsic() is allowed here.
1016 set_native_function(
1017 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1018 !native_bind_event_is_interesting);
1019 this->unlink_code();
1020 }
1021
1022
set_signature_handler(address handler)1023 void Method::set_signature_handler(address handler) {
1024 address* signature_handler = signature_handler_addr();
1025 *signature_handler = handler;
1026 }
1027
1028
print_made_not_compilable(int comp_level,bool is_osr,bool report,const char * reason)1029 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
1030 assert(reason != NULL, "must provide a reason");
1031 if (PrintCompilation && report) {
1032 ttyLocker ttyl;
1033 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
1034 if (comp_level == CompLevel_all) {
1035 tty->print("all levels ");
1036 } else {
1037 tty->print("level %d ", comp_level);
1038 }
1039 this->print_short_name(tty);
1040 int size = this->code_size();
1041 if (size > 0) {
1042 tty->print(" (%d bytes)", size);
1043 }
1044 if (reason != NULL) {
1045 tty->print(" %s", reason);
1046 }
1047 tty->cr();
1048 }
1049 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
1050 ttyLocker ttyl;
1051 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
1052 os::current_thread_id(), is_osr, comp_level);
1053 if (reason != NULL) {
1054 xtty->print(" reason=\'%s\'", reason);
1055 }
1056 xtty->method(this);
1057 xtty->stamp();
1058 xtty->end_elem();
1059 }
1060 }
1061
is_always_compilable() const1062 bool Method::is_always_compilable() const {
1063 // Generated adapters must be compiled
1064 if (is_method_handle_intrinsic() && is_synthetic()) {
1065 assert(!is_not_c1_compilable(), "sanity check");
1066 assert(!is_not_c2_compilable(), "sanity check");
1067 return true;
1068 }
1069
1070 return false;
1071 }
1072
is_not_compilable(int comp_level) const1073 bool Method::is_not_compilable(int comp_level) const {
1074 if (number_of_breakpoints() > 0)
1075 return true;
1076 if (is_always_compilable())
1077 return false;
1078 if (comp_level == CompLevel_any)
1079 return is_not_c1_compilable() && is_not_c2_compilable();
1080 if (is_c1_compile(comp_level))
1081 return is_not_c1_compilable();
1082 if (is_c2_compile(comp_level))
1083 return is_not_c2_compilable();
1084 return false;
1085 }
1086
1087 // call this when compiler finds that this method is not compilable
set_not_compilable(const char * reason,int comp_level,bool report)1088 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
1089 if (is_always_compilable()) {
1090 // Don't mark a method which should be always compilable
1091 return;
1092 }
1093 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
1094 if (comp_level == CompLevel_all) {
1095 set_not_c1_compilable();
1096 set_not_c2_compilable();
1097 } else {
1098 if (is_c1_compile(comp_level))
1099 set_not_c1_compilable();
1100 if (is_c2_compile(comp_level))
1101 set_not_c2_compilable();
1102 }
1103 assert(!CompilationPolicy::can_be_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1104 }
1105
is_not_osr_compilable(int comp_level) const1106 bool Method::is_not_osr_compilable(int comp_level) const {
1107 if (is_not_compilable(comp_level))
1108 return true;
1109 if (comp_level == CompLevel_any)
1110 return is_not_c1_osr_compilable() && is_not_c2_osr_compilable();
1111 if (is_c1_compile(comp_level))
1112 return is_not_c1_osr_compilable();
1113 if (is_c2_compile(comp_level))
1114 return is_not_c2_osr_compilable();
1115 return false;
1116 }
1117
set_not_osr_compilable(const char * reason,int comp_level,bool report)1118 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
1119 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
1120 if (comp_level == CompLevel_all) {
1121 set_not_c1_osr_compilable();
1122 set_not_c2_osr_compilable();
1123 } else {
1124 if (is_c1_compile(comp_level))
1125 set_not_c1_osr_compilable();
1126 if (is_c2_compile(comp_level))
1127 set_not_c2_osr_compilable();
1128 }
1129 assert(!CompilationPolicy::can_be_osr_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1130 }
1131
1132 // Revert to using the interpreter and clear out the nmethod
clear_code()1133 void Method::clear_code() {
1134 // this may be NULL if c2i adapters have not been made yet
1135 // Only should happen at allocate time.
1136 if (adapter() == NULL) {
1137 _from_compiled_entry = NULL;
1138 } else {
1139 _from_compiled_entry = adapter()->get_c2i_entry();
1140 }
1141 OrderAccess::storestore();
1142 _from_interpreted_entry = _i2i_entry;
1143 OrderAccess::storestore();
1144 _code = NULL;
1145 }
1146
unlink_code(CompiledMethod * compare)1147 void Method::unlink_code(CompiledMethod *compare) {
1148 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1149 // We need to check if either the _code or _from_compiled_code_entry_point
1150 // refer to this nmethod because there is a race in setting these two fields
1151 // in Method* as seen in bugid 4947125.
1152 // If the vep() points to the zombie nmethod, the memory for the nmethod
1153 // could be flushed and the compiler and vtable stubs could still call
1154 // through it.
1155 if (code() == compare ||
1156 from_compiled_entry() == compare->verified_entry_point()) {
1157 clear_code();
1158 }
1159 }
1160
unlink_code()1161 void Method::unlink_code() {
1162 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1163 clear_code();
1164 }
1165
1166 #if INCLUDE_CDS
1167 // Called by class data sharing to remove any entry points (which are not shared)
unlink_method()1168 void Method::unlink_method() {
1169 Arguments::assert_is_dumping_archive();
1170 _code = NULL;
1171 _adapter = NULL;
1172 _i2i_entry = NULL;
1173 _from_compiled_entry = NULL;
1174 _from_interpreted_entry = NULL;
1175
1176 if (is_native()) {
1177 *native_function_addr() = NULL;
1178 set_signature_handler(NULL);
1179 }
1180 NOT_PRODUCT(set_compiled_invocation_count(0);)
1181
1182 set_method_data(NULL);
1183 clear_method_counters();
1184 }
1185 #endif
1186
1187 // Called when the method_holder is getting linked. Setup entrypoints so the method
1188 // is ready to be called from interpreter, compiler, and vtables.
link_method(const methodHandle & h_method,TRAPS)1189 void Method::link_method(const methodHandle& h_method, TRAPS) {
1190 // If the code cache is full, we may reenter this function for the
1191 // leftover methods that weren't linked.
1192 if (_i2i_entry != NULL) {
1193 return;
1194 }
1195 assert( _code == NULL, "nothing compiled yet" );
1196
1197 // Setup interpreter entrypoint
1198 assert(this == h_method(), "wrong h_method()" );
1199
1200 assert(adapter() == NULL, "init'd to NULL");
1201 address entry = Interpreter::entry_for_method(h_method);
1202 assert(entry != NULL, "interpreter entry must be non-null");
1203 // Sets both _i2i_entry and _from_interpreted_entry
1204 set_interpreter_entry(entry);
1205
1206 // Don't overwrite already registered native entries.
1207 if (is_native() && !has_native_function()) {
1208 set_native_function(
1209 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1210 !native_bind_event_is_interesting);
1211 }
1212
1213 // Setup compiler entrypoint. This is made eagerly, so we do not need
1214 // special handling of vtables. An alternative is to make adapters more
1215 // lazily by calling make_adapter() from from_compiled_entry() for the
1216 // normal calls. For vtable calls life gets more complicated. When a
1217 // call-site goes mega-morphic we need adapters in all methods which can be
1218 // called from the vtable. We need adapters on such methods that get loaded
1219 // later. Ditto for mega-morphic itable calls. If this proves to be a
1220 // problem we'll make these lazily later.
1221 (void) make_adapters(h_method, CHECK);
1222
1223 // ONLY USE the h_method now as make_adapter may have blocked
1224 }
1225
make_adapters(const methodHandle & mh,TRAPS)1226 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1227 // Adapters for compiled code are made eagerly here. They are fairly
1228 // small (generally < 100 bytes) and quick to make (and cached and shared)
1229 // so making them eagerly shouldn't be too expensive.
1230 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1231 if (adapter == NULL ) {
1232 if (!is_init_completed()) {
1233 // Don't throw exceptions during VM initialization because java.lang.* classes
1234 // might not have been initialized, causing problems when constructing the
1235 // Java exception object.
1236 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1237 } else {
1238 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1239 }
1240 }
1241
1242 mh->set_adapter_entry(adapter);
1243 mh->_from_compiled_entry = adapter->get_c2i_entry();
1244 return adapter->get_c2i_entry();
1245 }
1246
restore_unshareable_info(TRAPS)1247 void Method::restore_unshareable_info(TRAPS) {
1248 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1249 }
1250
from_compiled_entry_no_trampoline() const1251 address Method::from_compiled_entry_no_trampoline() const {
1252 CompiledMethod *code = Atomic::load_acquire(&_code);
1253 if (code) {
1254 return code->verified_entry_point();
1255 } else {
1256 return adapter()->get_c2i_entry();
1257 }
1258 }
1259
1260 // The verified_code_entry() must be called when a invoke is resolved
1261 // on this method.
1262
1263 // It returns the compiled code entry point, after asserting not null.
1264 // This function is called after potential safepoints so that nmethod
1265 // or adapter that it points to is still live and valid.
1266 // This function must not hit a safepoint!
verified_code_entry()1267 address Method::verified_code_entry() {
1268 debug_only(NoSafepointVerifier nsv;)
1269 assert(_from_compiled_entry != NULL, "must be set");
1270 return _from_compiled_entry;
1271 }
1272
1273 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1274 // (could be racing a deopt).
1275 // Not inline to avoid circular ref.
check_code() const1276 bool Method::check_code() const {
1277 // cached in a register or local. There's a race on the value of the field.
1278 CompiledMethod *code = Atomic::load_acquire(&_code);
1279 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1280 }
1281
1282 // Install compiled code. Instantly it can execute.
set_code(const methodHandle & mh,CompiledMethod * code)1283 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1284 assert_lock_strong(CompiledMethod_lock);
1285 assert( code, "use clear_code to remove code" );
1286 assert( mh->check_code(), "" );
1287
1288 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1289
1290 // These writes must happen in this order, because the interpreter will
1291 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1292 // which jumps to _from_compiled_entry.
1293 mh->_code = code; // Assign before allowing compiled code to exec
1294
1295 int comp_level = code->comp_level();
1296 // In theory there could be a race here. In practice it is unlikely
1297 // and not worth worrying about.
1298 if (comp_level > mh->highest_comp_level()) {
1299 mh->set_highest_comp_level(comp_level);
1300 }
1301
1302 OrderAccess::storestore();
1303 mh->_from_compiled_entry = code->verified_entry_point();
1304 OrderAccess::storestore();
1305 // Instantly compiled code can execute.
1306 if (!mh->is_method_handle_intrinsic())
1307 mh->_from_interpreted_entry = mh->get_i2c_entry();
1308 }
1309
1310
is_overridden_in(Klass * k) const1311 bool Method::is_overridden_in(Klass* k) const {
1312 InstanceKlass* ik = InstanceKlass::cast(k);
1313
1314 if (ik->is_interface()) return false;
1315
1316 // If method is an interface, we skip it - except if it
1317 // is a miranda method
1318 if (method_holder()->is_interface()) {
1319 // Check that method is not a miranda method
1320 if (ik->lookup_method(name(), signature()) == NULL) {
1321 // No implementation exist - so miranda method
1322 return false;
1323 }
1324 return true;
1325 }
1326
1327 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1328 if (!has_vtable_index()) {
1329 return false;
1330 } else {
1331 Method* vt_m = ik->method_at_vtable(vtable_index());
1332 return vt_m != this;
1333 }
1334 }
1335
1336
1337 // give advice about whether this Method* should be cached or not
should_not_be_cached() const1338 bool Method::should_not_be_cached() const {
1339 if (is_old()) {
1340 // This method has been redefined. It is either EMCP or obsolete
1341 // and we don't want to cache it because that would pin the method
1342 // down and prevent it from being collectible if and when it
1343 // finishes executing.
1344 return true;
1345 }
1346
1347 // caching this method should be just fine
1348 return false;
1349 }
1350
1351
1352 /**
1353 * Returns true if this is one of the specially treated methods for
1354 * security related stack walks (like Reflection.getCallerClass).
1355 */
is_ignored_by_security_stack_walk() const1356 bool Method::is_ignored_by_security_stack_walk() const {
1357 if (intrinsic_id() == vmIntrinsics::_invoke) {
1358 // This is Method.invoke() -- ignore it
1359 return true;
1360 }
1361 if (method_holder()->is_subclass_of(vmClasses::reflect_MethodAccessorImpl_klass())) {
1362 // This is an auxilary frame -- ignore it
1363 return true;
1364 }
1365 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1366 // This is an internal adapter frame for method handles -- ignore it
1367 return true;
1368 }
1369 return false;
1370 }
1371
1372
1373 // Constant pool structure for invoke methods:
1374 enum {
1375 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1376 _imcp_invoke_signature, // utf8: (variable Symbol*)
1377 _imcp_limit
1378 };
1379
1380 // Test if this method is an MH adapter frame generated by Java code.
1381 // Cf. java/lang/invoke/InvokerBytecodeGenerator
is_compiled_lambda_form() const1382 bool Method::is_compiled_lambda_form() const {
1383 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1384 }
1385
1386 // Test if this method is an internal MH primitive method.
is_method_handle_intrinsic() const1387 bool Method::is_method_handle_intrinsic() const {
1388 vmIntrinsics::ID iid = intrinsic_id();
1389 return (MethodHandles::is_signature_polymorphic(iid) &&
1390 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1391 }
1392
has_member_arg() const1393 bool Method::has_member_arg() const {
1394 vmIntrinsics::ID iid = intrinsic_id();
1395 return (MethodHandles::is_signature_polymorphic(iid) &&
1396 MethodHandles::has_member_arg(iid));
1397 }
1398
1399 // Make an instance of a signature-polymorphic internal MH primitive.
make_method_handle_intrinsic(vmIntrinsics::ID iid,Symbol * signature,TRAPS)1400 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1401 Symbol* signature,
1402 TRAPS) {
1403 ResourceMark rm(THREAD);
1404 methodHandle empty;
1405
1406 InstanceKlass* holder = vmClasses::MethodHandle_klass();
1407 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1408 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1409
1410 log_info(methodhandles)("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1411
1412 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1413 name->increment_refcount();
1414 signature->increment_refcount();
1415
1416 int cp_length = _imcp_limit;
1417 ClassLoaderData* loader_data = holder->class_loader_data();
1418 constantPoolHandle cp;
1419 {
1420 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1421 cp = constantPoolHandle(THREAD, cp_oop);
1422 }
1423 cp->copy_fields(holder->constants());
1424 cp->set_pool_holder(holder);
1425 cp->symbol_at_put(_imcp_invoke_name, name);
1426 cp->symbol_at_put(_imcp_invoke_signature, signature);
1427 cp->set_has_preresolution();
1428
1429 // decide on access bits: public or not?
1430 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1431 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1432 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1433 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1434
1435 methodHandle m;
1436 {
1437 InlineTableSizes sizes;
1438 Method* m_oop = Method::allocate(loader_data, 0,
1439 accessFlags_from(flags_bits), &sizes,
1440 ConstMethod::NORMAL, CHECK_(empty));
1441 m = methodHandle(THREAD, m_oop);
1442 }
1443 m->set_constants(cp());
1444 m->set_name_index(_imcp_invoke_name);
1445 m->set_signature_index(_imcp_invoke_signature);
1446 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1447 assert(m->signature() == signature, "");
1448 m->compute_from_signature(signature);
1449 m->init_intrinsic_id(klass_id_for_intrinsics(m->method_holder()));
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 (iid == vmIntrinsics::_linkToNative) {
1463 m->set_interpreter_entry(m->adapter()->get_i2c_entry());
1464 }
1465 if (log_is_enabled(Info, methodhandles) && (Verbose || WizardMode)) {
1466 LogTarget(Info, methodhandles) lt;
1467 LogStream ls(lt);
1468 m->print_on(&ls);
1469 }
1470
1471 return m;
1472 }
1473
check_non_bcp_klass(Klass * klass)1474 Klass* Method::check_non_bcp_klass(Klass* klass) {
1475 if (klass != NULL && klass->class_loader() != NULL) {
1476 if (klass->is_objArray_klass())
1477 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1478 return klass;
1479 }
1480 return NULL;
1481 }
1482
1483
clone_with_new_data(const methodHandle & m,u_char * new_code,int new_code_length,u_char * new_compressed_linenumber_table,int new_compressed_linenumber_size,TRAPS)1484 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1485 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1486 // Code below does not work for native methods - they should never get rewritten anyway
1487 assert(!m->is_native(), "cannot rewrite native methods");
1488 // Allocate new Method*
1489 AccessFlags flags = m->access_flags();
1490
1491 ConstMethod* cm = m->constMethod();
1492 int checked_exceptions_len = cm->checked_exceptions_length();
1493 int localvariable_len = cm->localvariable_table_length();
1494 int exception_table_len = cm->exception_table_length();
1495 int method_parameters_len = cm->method_parameters_length();
1496 int method_annotations_len = cm->method_annotations_length();
1497 int parameter_annotations_len = cm->parameter_annotations_length();
1498 int type_annotations_len = cm->type_annotations_length();
1499 int default_annotations_len = cm->default_annotations_length();
1500
1501 InlineTableSizes sizes(
1502 localvariable_len,
1503 new_compressed_linenumber_size,
1504 exception_table_len,
1505 checked_exceptions_len,
1506 method_parameters_len,
1507 cm->generic_signature_index(),
1508 method_annotations_len,
1509 parameter_annotations_len,
1510 type_annotations_len,
1511 default_annotations_len,
1512 0);
1513
1514 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1515 Method* newm_oop = Method::allocate(loader_data,
1516 new_code_length,
1517 flags,
1518 &sizes,
1519 m->method_type(),
1520 CHECK_(methodHandle()));
1521 methodHandle newm (THREAD, newm_oop);
1522
1523 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1524 ConstMethod* newcm = newm->constMethod();
1525 int new_const_method_size = newm->constMethod()->size();
1526
1527 // This works because the source and target are both Methods. Some compilers
1528 // (e.g., clang) complain that the target vtable pointer will be stomped,
1529 // so cast away newm()'s and m()'s Methodness.
1530 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1531
1532 // Create shallow copy of ConstMethod.
1533 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1534
1535 // Reset correct method/const method, method size, and parameter info
1536 newm->set_constMethod(newcm);
1537 newm->constMethod()->set_code_size(new_code_length);
1538 newm->constMethod()->set_constMethod_size(new_const_method_size);
1539 assert(newm->code_size() == new_code_length, "check");
1540 assert(newm->method_parameters_length() == method_parameters_len, "check");
1541 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1542 assert(newm->exception_table_length() == exception_table_len, "check");
1543 assert(newm->localvariable_table_length() == localvariable_len, "check");
1544 // Copy new byte codes
1545 memcpy(newm->code_base(), new_code, new_code_length);
1546 // Copy line number table
1547 if (new_compressed_linenumber_size > 0) {
1548 memcpy(newm->compressed_linenumber_table(),
1549 new_compressed_linenumber_table,
1550 new_compressed_linenumber_size);
1551 }
1552 // Copy method_parameters
1553 if (method_parameters_len > 0) {
1554 memcpy(newm->method_parameters_start(),
1555 m->method_parameters_start(),
1556 method_parameters_len * sizeof(MethodParametersElement));
1557 }
1558 // Copy checked_exceptions
1559 if (checked_exceptions_len > 0) {
1560 memcpy(newm->checked_exceptions_start(),
1561 m->checked_exceptions_start(),
1562 checked_exceptions_len * sizeof(CheckedExceptionElement));
1563 }
1564 // Copy exception table
1565 if (exception_table_len > 0) {
1566 memcpy(newm->exception_table_start(),
1567 m->exception_table_start(),
1568 exception_table_len * sizeof(ExceptionTableElement));
1569 }
1570 // Copy local variable number table
1571 if (localvariable_len > 0) {
1572 memcpy(newm->localvariable_table_start(),
1573 m->localvariable_table_start(),
1574 localvariable_len * sizeof(LocalVariableTableElement));
1575 }
1576 // Copy stackmap table
1577 if (m->has_stackmap_table()) {
1578 int code_attribute_length = m->stackmap_data()->length();
1579 Array<u1>* stackmap_data =
1580 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_(methodHandle()));
1581 memcpy((void*)stackmap_data->adr_at(0),
1582 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1583 newm->set_stackmap_data(stackmap_data);
1584 }
1585
1586 // copy annotations over to new method
1587 newcm->copy_annotations_from(loader_data, cm, CHECK_(methodHandle()));
1588 return newm;
1589 }
1590
klass_id_for_intrinsics(const Klass * holder)1591 vmSymbolID Method::klass_id_for_intrinsics(const Klass* holder) {
1592 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1593 // because we are not loading from core libraries
1594 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1595 // which does not use the class default class loader so we check for its loader here
1596 const InstanceKlass* ik = InstanceKlass::cast(holder);
1597 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1598 return vmSymbolID::NO_SID; // regardless of name, no intrinsics here
1599 }
1600
1601 // see if the klass name is well-known:
1602 Symbol* klass_name = ik->name();
1603 vmSymbolID id = vmSymbols::find_sid(klass_name);
1604 if (id != vmSymbolID::NO_SID && vmIntrinsics::class_has_intrinsics(id)) {
1605 return id;
1606 } else {
1607 return vmSymbolID::NO_SID;
1608 }
1609 }
1610
init_intrinsic_id(vmSymbolID klass_id)1611 void Method::init_intrinsic_id(vmSymbolID klass_id) {
1612 assert(_intrinsic_id == static_cast<int>(vmIntrinsics::_none), "do this just once");
1613 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1614 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1615 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1616
1617 // the klass name is well-known:
1618 assert(klass_id == klass_id_for_intrinsics(method_holder()), "must be");
1619 assert(klass_id != vmSymbolID::NO_SID, "caller responsibility");
1620
1621 // ditto for method and signature:
1622 vmSymbolID name_id = vmSymbols::find_sid(name());
1623 if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1624 && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1625 && name_id == vmSymbolID::NO_SID) {
1626 return;
1627 }
1628 vmSymbolID sig_id = vmSymbols::find_sid(signature());
1629 if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1630 && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1631 && sig_id == vmSymbolID::NO_SID) {
1632 return;
1633 }
1634 jshort flags = access_flags().as_short();
1635
1636 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1637 if (id != vmIntrinsics::_none) {
1638 set_intrinsic_id(id);
1639 if (id == vmIntrinsics::_Class_cast) {
1640 // Even if the intrinsic is rejected, we want to inline this simple method.
1641 set_force_inline(true);
1642 }
1643 return;
1644 }
1645
1646 // A few slightly irregular cases:
1647 switch (klass_id) {
1648 case VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1649 // Second chance: check in regular Math.
1650 switch (name_id) {
1651 case VM_SYMBOL_ENUM_NAME(min_name):
1652 case VM_SYMBOL_ENUM_NAME(max_name):
1653 case VM_SYMBOL_ENUM_NAME(sqrt_name):
1654 // pretend it is the corresponding method in the non-strict class:
1655 klass_id = VM_SYMBOL_ENUM_NAME(java_lang_Math);
1656 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1657 break;
1658 default:
1659 break;
1660 }
1661 break;
1662
1663 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1664 case VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1665 case VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1666 if (!is_native()) break;
1667 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1668 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1669 id = vmIntrinsics::_none;
1670 break;
1671
1672 default:
1673 break;
1674 }
1675
1676 if (id != vmIntrinsics::_none) {
1677 // Set up its iid. It is an alias method.
1678 set_intrinsic_id(id);
1679 return;
1680 }
1681 }
1682
load_signature_classes(const methodHandle & m,TRAPS)1683 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1684 if (!THREAD->can_call_java()) {
1685 // There is nothing useful this routine can do from within the Compile thread.
1686 // Hopefully, the signature contains only well-known classes.
1687 // We could scan for this and return true/false, but the caller won't care.
1688 return false;
1689 }
1690 bool sig_is_loaded = true;
1691 ResourceMark rm(THREAD);
1692 for (ResolvingSignatureStream ss(m()); !ss.is_done(); ss.next()) {
1693 if (ss.is_reference()) {
1694 // load everything, including arrays "[Lfoo;"
1695 Klass* klass = ss.as_klass(SignatureStream::ReturnNull, THREAD);
1696 // We are loading classes eagerly. If a ClassNotFoundException or
1697 // a LinkageError was generated, be sure to ignore it.
1698 if (HAS_PENDING_EXCEPTION) {
1699 if (PENDING_EXCEPTION->is_a(vmClasses::ClassNotFoundException_klass()) ||
1700 PENDING_EXCEPTION->is_a(vmClasses::LinkageError_klass())) {
1701 CLEAR_PENDING_EXCEPTION;
1702 } else {
1703 return false;
1704 }
1705 }
1706 if( klass == NULL) { sig_is_loaded = false; }
1707 }
1708 }
1709 return sig_is_loaded;
1710 }
1711
has_unloaded_classes_in_signature(const methodHandle & m,TRAPS)1712 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1713 ResourceMark rm(THREAD);
1714 for(ResolvingSignatureStream ss(m()); !ss.is_done(); ss.next()) {
1715 if (ss.type() == T_OBJECT) {
1716 // Do not use ss.is_reference() here, since we don't care about
1717 // unloaded array component types.
1718 Klass* klass = ss.as_klass_if_loaded(THREAD);
1719 assert(!HAS_PENDING_EXCEPTION, "as_klass_if_loaded contract");
1720 if (klass == NULL) return true;
1721 }
1722 }
1723 return false;
1724 }
1725
1726 // Exposed so field engineers can debug VM
print_short_name(outputStream * st)1727 void Method::print_short_name(outputStream* st) {
1728 ResourceMark rm;
1729 #ifdef PRODUCT
1730 st->print(" %s::", method_holder()->external_name());
1731 #else
1732 st->print(" %s::", method_holder()->internal_name());
1733 #endif
1734 name()->print_symbol_on(st);
1735 if (WizardMode) signature()->print_symbol_on(st);
1736 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1737 MethodHandles::print_as_basic_type_signature_on(st, signature());
1738 }
1739
1740 // Comparer for sorting an object array containing
1741 // Method*s.
method_comparator(Method * a,Method * b)1742 static int method_comparator(Method* a, Method* b) {
1743 return a->name()->fast_compare(b->name());
1744 }
1745
1746 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1747 // default_methods also uses this without the ordering for fast find_method
sort_methods(Array<Method * > * methods,bool set_idnums,method_comparator_func func)1748 void Method::sort_methods(Array<Method*>* methods, bool set_idnums, method_comparator_func func) {
1749 int length = methods->length();
1750 if (length > 1) {
1751 if (func == NULL) {
1752 func = method_comparator;
1753 }
1754 {
1755 NoSafepointVerifier nsv;
1756 QuickSort::sort(methods->data(), length, func, /*idempotent=*/false);
1757 }
1758 // Reset method ordering
1759 if (set_idnums) {
1760 for (int i = 0; i < length; i++) {
1761 Method* m = methods->at(i);
1762 m->set_method_idnum(i);
1763 m->set_orig_method_idnum(i);
1764 }
1765 }
1766 }
1767 }
1768
1769 //-----------------------------------------------------------------------------------
1770 // Non-product code unless JVM/TI needs it
1771
1772 #if !defined(PRODUCT) || INCLUDE_JVMTI
1773 class SignatureTypePrinter : public SignatureTypeNames {
1774 private:
1775 outputStream* _st;
1776 bool _use_separator;
1777
type_name(const char * name)1778 void type_name(const char* name) {
1779 if (_use_separator) _st->print(", ");
1780 _st->print("%s", name);
1781 _use_separator = true;
1782 }
1783
1784 public:
SignatureTypePrinter(Symbol * signature,outputStream * st)1785 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1786 _st = st;
1787 _use_separator = false;
1788 }
1789
print_parameters()1790 void print_parameters() { _use_separator = false; do_parameters_on(this); }
print_returntype()1791 void print_returntype() { _use_separator = false; do_type(return_type()); }
1792 };
1793
1794
print_name(outputStream * st)1795 void Method::print_name(outputStream* st) {
1796 Thread *thread = Thread::current();
1797 ResourceMark rm(thread);
1798 st->print("%s ", is_static() ? "static" : "virtual");
1799 if (WizardMode) {
1800 st->print("%s.", method_holder()->internal_name());
1801 name()->print_symbol_on(st);
1802 signature()->print_symbol_on(st);
1803 } else {
1804 SignatureTypePrinter sig(signature(), st);
1805 sig.print_returntype();
1806 st->print(" %s.", method_holder()->internal_name());
1807 name()->print_symbol_on(st);
1808 st->print("(");
1809 sig.print_parameters();
1810 st->print(")");
1811 }
1812 }
1813 #endif // !PRODUCT || INCLUDE_JVMTI
1814
1815
print_codes_on(outputStream * st) const1816 void Method::print_codes_on(outputStream* st) const {
1817 print_codes_on(0, code_size(), st);
1818 }
1819
print_codes_on(int from,int to,outputStream * st) const1820 void Method::print_codes_on(int from, int to, outputStream* st) const {
1821 Thread *thread = Thread::current();
1822 ResourceMark rm(thread);
1823 methodHandle mh (thread, (Method*)this);
1824 BytecodeStream s(mh);
1825 s.set_interval(from, to);
1826 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1827 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1828 }
1829
CompressedLineNumberReadStream(u_char * buffer)1830 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1831 _bci = 0;
1832 _line = 0;
1833 };
1834
read_pair()1835 bool CompressedLineNumberReadStream::read_pair() {
1836 jubyte next = read_byte();
1837 // Check for terminator
1838 if (next == 0) return false;
1839 if (next == 0xFF) {
1840 // Escape character, regular compression used
1841 _bci += read_signed_int();
1842 _line += read_signed_int();
1843 } else {
1844 // Single byte compression used
1845 _bci += next >> 3;
1846 _line += next & 0x7;
1847 }
1848 return true;
1849 }
1850
1851 #if INCLUDE_JVMTI
1852
orig_bytecode_at(int bci) const1853 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1854 BreakpointInfo* bp = method_holder()->breakpoints();
1855 for (; bp != NULL; bp = bp->next()) {
1856 if (bp->match(this, bci)) {
1857 return bp->orig_bytecode();
1858 }
1859 }
1860 {
1861 ResourceMark rm;
1862 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1863 }
1864 return Bytecodes::_shouldnotreachhere;
1865 }
1866
set_orig_bytecode_at(int bci,Bytecodes::Code code)1867 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1868 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1869 BreakpointInfo* bp = method_holder()->breakpoints();
1870 for (; bp != NULL; bp = bp->next()) {
1871 if (bp->match(this, bci)) {
1872 bp->set_orig_bytecode(code);
1873 // and continue, in case there is more than one
1874 }
1875 }
1876 }
1877
set_breakpoint(int bci)1878 void Method::set_breakpoint(int bci) {
1879 InstanceKlass* ik = method_holder();
1880 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1881 bp->set_next(ik->breakpoints());
1882 ik->set_breakpoints(bp);
1883 // do this last:
1884 bp->set(this);
1885 }
1886
clear_matches(Method * m,int bci)1887 static void clear_matches(Method* m, int bci) {
1888 InstanceKlass* ik = m->method_holder();
1889 BreakpointInfo* prev_bp = NULL;
1890 BreakpointInfo* next_bp;
1891 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1892 next_bp = bp->next();
1893 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1894 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1895 // do this first:
1896 bp->clear(m);
1897 // unhook it
1898 if (prev_bp != NULL)
1899 prev_bp->set_next(next_bp);
1900 else
1901 ik->set_breakpoints(next_bp);
1902 delete bp;
1903 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1904 // at same location. So we have multiple matching (method_index and bci)
1905 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1906 // breakpoint for clear_breakpoint request and keep all other method versions
1907 // BreakpointInfo for future clear_breakpoint request.
1908 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1909 // which is being called when class is unloaded. We delete all the Breakpoint
1910 // information for all versions of method. We may not correctly restore the original
1911 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1912 // so these methods won't be used anymore.
1913 if (bci >= 0) {
1914 break;
1915 }
1916 } else {
1917 // This one is a keeper.
1918 prev_bp = bp;
1919 }
1920 }
1921 }
1922
clear_breakpoint(int bci)1923 void Method::clear_breakpoint(int bci) {
1924 assert(bci >= 0, "");
1925 clear_matches(this, bci);
1926 }
1927
clear_all_breakpoints()1928 void Method::clear_all_breakpoints() {
1929 clear_matches(this, -1);
1930 }
1931
1932 #endif // INCLUDE_JVMTI
1933
invocation_count() const1934 int Method::invocation_count() const {
1935 MethodCounters* mcs = method_counters();
1936 MethodData* 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 }
1945
backedge_count() const1946 int Method::backedge_count() const {
1947 MethodCounters* mcs = method_counters();
1948 MethodData* mdo = method_data();
1949 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1950 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1951 return InvocationCounter::count_limit;
1952 } else {
1953 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1954 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1955 }
1956 }
1957
highest_comp_level() const1958 int Method::highest_comp_level() const {
1959 const MethodCounters* mcs = method_counters();
1960 if (mcs != NULL) {
1961 return mcs->highest_comp_level();
1962 } else {
1963 return CompLevel_none;
1964 }
1965 }
1966
highest_osr_comp_level() const1967 int Method::highest_osr_comp_level() const {
1968 const MethodCounters* mcs = method_counters();
1969 if (mcs != NULL) {
1970 return mcs->highest_osr_comp_level();
1971 } else {
1972 return CompLevel_none;
1973 }
1974 }
1975
set_highest_comp_level(int level)1976 void Method::set_highest_comp_level(int level) {
1977 MethodCounters* mcs = method_counters();
1978 if (mcs != NULL) {
1979 mcs->set_highest_comp_level(level);
1980 }
1981 }
1982
set_highest_osr_comp_level(int level)1983 void Method::set_highest_osr_comp_level(int level) {
1984 MethodCounters* mcs = method_counters();
1985 if (mcs != NULL) {
1986 mcs->set_highest_osr_comp_level(level);
1987 }
1988 }
1989
1990 #if INCLUDE_JVMTI
1991
BreakpointInfo(Method * m,int bci)1992 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1993 _bci = bci;
1994 _name_index = m->name_index();
1995 _signature_index = m->signature_index();
1996 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1997 if (_orig_bytecode == Bytecodes::_breakpoint)
1998 _orig_bytecode = m->orig_bytecode_at(_bci);
1999 _next = NULL;
2000 }
2001
set(Method * method)2002 void BreakpointInfo::set(Method* method) {
2003 #ifdef ASSERT
2004 {
2005 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
2006 if (code == Bytecodes::_breakpoint)
2007 code = method->orig_bytecode_at(_bci);
2008 assert(orig_bytecode() == code, "original bytecode must be the same");
2009 }
2010 #endif
2011 Thread *thread = Thread::current();
2012 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
2013 method->incr_number_of_breakpoints(thread);
2014 {
2015 // Deoptimize all dependents on this method
2016 HandleMark hm(thread);
2017 methodHandle mh(thread, method);
2018 CodeCache::flush_dependents_on_method(mh);
2019 }
2020 }
2021
clear(Method * method)2022 void BreakpointInfo::clear(Method* method) {
2023 *method->bcp_from(_bci) = orig_bytecode();
2024 assert(method->number_of_breakpoints() > 0, "must not go negative");
2025 method->decr_number_of_breakpoints(Thread::current());
2026 }
2027
2028 #endif // INCLUDE_JVMTI
2029
2030 // jmethodID handling
2031
2032 // This is a block allocating object, sort of like JNIHandleBlock, only a
2033 // lot simpler.
2034 // It's allocated on the CHeap because once we allocate a jmethodID, we can
2035 // never get rid of it.
2036
2037 static const int min_block_size = 8;
2038
2039 class JNIMethodBlockNode : public CHeapObj<mtClass> {
2040 friend class JNIMethodBlock;
2041 Method** _methods;
2042 int _number_of_methods;
2043 int _top;
2044 JNIMethodBlockNode* _next;
2045
2046 public:
2047
2048 JNIMethodBlockNode(int num_methods = min_block_size);
2049
~JNIMethodBlockNode()2050 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
2051
ensure_methods(int num_addl_methods)2052 void ensure_methods(int num_addl_methods) {
2053 if (_top < _number_of_methods) {
2054 num_addl_methods -= _number_of_methods - _top;
2055 if (num_addl_methods <= 0) {
2056 return;
2057 }
2058 }
2059 if (_next == NULL) {
2060 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
2061 } else {
2062 _next->ensure_methods(num_addl_methods);
2063 }
2064 }
2065 };
2066
2067 class JNIMethodBlock : public CHeapObj<mtClass> {
2068 JNIMethodBlockNode _head;
2069 JNIMethodBlockNode *_last_free;
2070 public:
2071 static Method* const _free_method;
2072
JNIMethodBlock(int initial_capacity=min_block_size)2073 JNIMethodBlock(int initial_capacity = min_block_size)
2074 : _head(initial_capacity), _last_free(&_head) {}
2075
ensure_methods(int num_addl_methods)2076 void ensure_methods(int num_addl_methods) {
2077 _last_free->ensure_methods(num_addl_methods);
2078 }
2079
add_method(Method * m)2080 Method** add_method(Method* m) {
2081 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2082 if (b->_top < b->_number_of_methods) {
2083 // top points to the next free entry.
2084 int i = b->_top;
2085 b->_methods[i] = m;
2086 b->_top++;
2087 _last_free = b;
2088 return &(b->_methods[i]);
2089 } else if (b->_top == b->_number_of_methods) {
2090 // if the next free entry ran off the block see if there's a free entry
2091 for (int i = 0; i < b->_number_of_methods; i++) {
2092 if (b->_methods[i] == _free_method) {
2093 b->_methods[i] = m;
2094 _last_free = b;
2095 return &(b->_methods[i]);
2096 }
2097 }
2098 // Only check each block once for frees. They're very unlikely.
2099 // Increment top past the end of the block.
2100 b->_top++;
2101 }
2102 // need to allocate a next block.
2103 if (b->_next == NULL) {
2104 b->_next = _last_free = new JNIMethodBlockNode();
2105 }
2106 }
2107 guarantee(false, "Should always allocate a free block");
2108 return NULL;
2109 }
2110
contains(Method ** m)2111 bool contains(Method** m) {
2112 if (m == NULL) return false;
2113 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2114 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2115 // This is a bit of extra checking, for two reasons. One is
2116 // that contains() deals with pointers that are passed in by
2117 // JNI code, so making sure that the pointer is aligned
2118 // correctly is valuable. The other is that <= and > are
2119 // technically not defined on pointers, so the if guard can
2120 // pass spuriously; no modern compiler is likely to make that
2121 // a problem, though (and if one did, the guard could also
2122 // fail spuriously, which would be bad).
2123 ptrdiff_t idx = m - b->_methods;
2124 if (b->_methods + idx == m) {
2125 return true;
2126 }
2127 }
2128 }
2129 return false; // not found
2130 }
2131
2132 // Doesn't really destroy it, just marks it as free so it can be reused.
destroy_method(Method ** m)2133 void destroy_method(Method** m) {
2134 #ifdef ASSERT
2135 assert(contains(m), "should be a methodID");
2136 #endif // ASSERT
2137 *m = _free_method;
2138 }
2139
2140 // During class unloading the methods are cleared, which is different
2141 // than freed.
clear_all_methods()2142 void clear_all_methods() {
2143 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2144 for (int i = 0; i< b->_number_of_methods; i++) {
2145 b->_methods[i] = NULL;
2146 }
2147 }
2148 }
2149 #ifndef PRODUCT
count_methods()2150 int count_methods() {
2151 // count all allocated methods
2152 int count = 0;
2153 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2154 for (int i = 0; i< b->_number_of_methods; i++) {
2155 if (b->_methods[i] != _free_method) count++;
2156 }
2157 }
2158 return count;
2159 }
2160 #endif // PRODUCT
2161 };
2162
2163 // Something that can't be mistaken for an address or a markWord
2164 Method* const JNIMethodBlock::_free_method = (Method*)55;
2165
JNIMethodBlockNode(int num_methods)2166 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2167 _number_of_methods = MAX2(num_methods, min_block_size);
2168 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2169 for (int i = 0; i < _number_of_methods; i++) {
2170 _methods[i] = JNIMethodBlock::_free_method;
2171 }
2172 }
2173
ensure_jmethod_ids(ClassLoaderData * loader_data,int capacity)2174 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2175 ClassLoaderData* cld = loader_data;
2176 if (!SafepointSynchronize::is_at_safepoint()) {
2177 // Have to add jmethod_ids() to class loader data thread-safely.
2178 // Also have to add the method to the list safely, which the lock
2179 // protects as well.
2180 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2181 if (cld->jmethod_ids() == NULL) {
2182 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2183 } else {
2184 cld->jmethod_ids()->ensure_methods(capacity);
2185 }
2186 } else {
2187 // At safepoint, we are single threaded and can set this.
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 }
2194 }
2195
2196 // Add a method id to the jmethod_ids
make_jmethod_id(ClassLoaderData * loader_data,Method * m)2197 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2198 ClassLoaderData* cld = loader_data;
2199
2200 if (!SafepointSynchronize::is_at_safepoint()) {
2201 // Have to add jmethod_ids() to class loader data thread-safely.
2202 // Also have to add the method to the list safely, which the lock
2203 // protects as well.
2204 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2205 if (cld->jmethod_ids() == NULL) {
2206 cld->set_jmethod_ids(new JNIMethodBlock());
2207 }
2208 // jmethodID is a pointer to Method*
2209 return (jmethodID)cld->jmethod_ids()->add_method(m);
2210 } else {
2211 // At safepoint, we are single threaded and can set this.
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 }
2218 }
2219
jmethod_id()2220 jmethodID Method::jmethod_id() {
2221 methodHandle mh(Thread::current(), this);
2222 return method_holder()->get_jmethod_id(mh);
2223 }
2224
2225 // Mark a jmethodID as free. This is called when there is a data race in
2226 // InstanceKlass while creating the jmethodID cache.
destroy_jmethod_id(ClassLoaderData * loader_data,jmethodID m)2227 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2228 ClassLoaderData* cld = loader_data;
2229 Method** ptr = (Method**)m;
2230 assert(cld->jmethod_ids() != NULL, "should have method handles");
2231 cld->jmethod_ids()->destroy_method(ptr);
2232 }
2233
change_method_associated_with_jmethod_id(jmethodID jmid,Method * new_method)2234 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2235 // Can't assert the method_holder is the same because the new method has the
2236 // scratch method holder.
2237 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2238 == new_method->method_holder()->class_loader() ||
2239 new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2240 "changing to a different class loader");
2241 // Just change the method in place, jmethodID pointer doesn't change.
2242 *((Method**)jmid) = new_method;
2243 }
2244
is_method_id(jmethodID mid)2245 bool Method::is_method_id(jmethodID mid) {
2246 Method* m = resolve_jmethod_id(mid);
2247 assert(m != NULL, "should be called with non-null method");
2248 InstanceKlass* ik = m->method_holder();
2249 ClassLoaderData* cld = ik->class_loader_data();
2250 if (cld->jmethod_ids() == NULL) return false;
2251 return (cld->jmethod_ids()->contains((Method**)mid));
2252 }
2253
checked_resolve_jmethod_id(jmethodID mid)2254 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2255 if (mid == NULL) return NULL;
2256 Method* o = resolve_jmethod_id(mid);
2257 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2258 return NULL;
2259 }
2260 return o;
2261 };
2262
set_on_stack(const bool value)2263 void Method::set_on_stack(const bool value) {
2264 // Set both the method itself and its constant pool. The constant pool
2265 // on stack means some method referring to it is also on the stack.
2266 constants()->set_on_stack(value);
2267
2268 bool already_set = on_stack();
2269 _access_flags.set_on_stack(value);
2270 if (value && !already_set) {
2271 MetadataOnStackMark::record(this);
2272 }
2273 }
2274
2275 // Called when the class loader is unloaded to make all methods weak.
clear_jmethod_ids(ClassLoaderData * loader_data)2276 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2277 loader_data->jmethod_ids()->clear_all_methods();
2278 }
2279
has_method_vptr(const void * ptr)2280 bool Method::has_method_vptr(const void* ptr) {
2281 Method m;
2282 // This assumes that the vtbl pointer is the first word of a C++ object.
2283 return dereference_vptr(&m) == dereference_vptr(ptr);
2284 }
2285
2286 // Check that this pointer is valid by checking that the vtbl pointer matches
is_valid_method(const Method * m)2287 bool Method::is_valid_method(const Method* m) {
2288 if (m == NULL) {
2289 return false;
2290 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2291 // Quick sanity check on pointer.
2292 return false;
2293 } else if (m->is_shared()) {
2294 return CppVtables::is_valid_shared_method(m);
2295 } else if (Metaspace::contains_non_shared(m)) {
2296 return has_method_vptr((const void*)m);
2297 } else {
2298 return false;
2299 }
2300 }
2301
2302 #ifndef PRODUCT
print_jmethod_ids_count(const ClassLoaderData * loader_data,outputStream * out)2303 void Method::print_jmethod_ids_count(const ClassLoaderData* loader_data, outputStream* out) {
2304 out->print("%d", loader_data->jmethod_ids()->count_methods());
2305 }
2306 #endif // PRODUCT
2307
2308
2309 // Printing
2310
2311 #ifndef PRODUCT
2312
print_on(outputStream * st) const2313 void Method::print_on(outputStream* st) const {
2314 ResourceMark rm;
2315 assert(is_method(), "must be method");
2316 st->print_cr("%s", internal_name());
2317 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2318 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2319 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2320 constants()->print_value_on(st); st->cr();
2321 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2322 st->print (" - name: "); name()->print_value_on(st); st->cr();
2323 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2324 st->print_cr(" - max stack: %d", max_stack());
2325 st->print_cr(" - max locals: %d", max_locals());
2326 st->print_cr(" - size of params: %d", size_of_parameters());
2327 st->print_cr(" - method size: %d", method_size());
2328 if (intrinsic_id() != vmIntrinsics::_none)
2329 st->print_cr(" - intrinsic id: %d %s", vmIntrinsics::as_int(intrinsic_id()), vmIntrinsics::name_at(intrinsic_id()));
2330 if (highest_comp_level() != CompLevel_none)
2331 st->print_cr(" - highest level: %d", highest_comp_level());
2332 st->print_cr(" - vtable index: %d", _vtable_index);
2333 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2334 st->print( " - adapters: ");
2335 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2336 if (a == NULL)
2337 st->print_cr(INTPTR_FORMAT, p2i(a));
2338 else
2339 a->print_adapter_on(st);
2340 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2341 st->print_cr(" - code size: %d", code_size());
2342 if (code_size() != 0) {
2343 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2344 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2345 }
2346 if (method_data() != NULL) {
2347 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2348 }
2349 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2350 if (checked_exceptions_length() > 0) {
2351 CheckedExceptionElement* table = checked_exceptions_start();
2352 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2353 if (Verbose) {
2354 for (int i = 0; i < checked_exceptions_length(); i++) {
2355 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2356 }
2357 }
2358 }
2359 if (has_linenumber_table()) {
2360 u_char* table = compressed_linenumber_table();
2361 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2362 if (Verbose) {
2363 CompressedLineNumberReadStream stream(table);
2364 while (stream.read_pair()) {
2365 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2366 }
2367 }
2368 }
2369 st->print_cr(" - localvar length: %d", localvariable_table_length());
2370 if (localvariable_table_length() > 0) {
2371 LocalVariableTableElement* table = localvariable_table_start();
2372 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2373 if (Verbose) {
2374 for (int i = 0; i < localvariable_table_length(); i++) {
2375 int bci = table[i].start_bci;
2376 int len = table[i].length;
2377 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2378 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2379 int slot = table[i].slot;
2380 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2381 }
2382 }
2383 }
2384 if (code() != NULL) {
2385 st->print (" - compiled code: ");
2386 code()->print_value_on(st);
2387 }
2388 if (is_native()) {
2389 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2390 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2391 }
2392 }
2393
print_linkage_flags(outputStream * st)2394 void Method::print_linkage_flags(outputStream* st) {
2395 access_flags().print_on(st);
2396 if (is_default_method()) {
2397 st->print("default ");
2398 }
2399 if (is_overpass()) {
2400 st->print("overpass ");
2401 }
2402 }
2403 #endif //PRODUCT
2404
print_value_on(outputStream * st) const2405 void Method::print_value_on(outputStream* st) const {
2406 assert(is_method(), "must be method");
2407 st->print("%s", internal_name());
2408 print_address_on(st);
2409 st->print(" ");
2410 name()->print_value_on(st);
2411 st->print(" ");
2412 signature()->print_value_on(st);
2413 st->print(" in ");
2414 method_holder()->print_value_on(st);
2415 if (WizardMode) st->print("#%d", _vtable_index);
2416 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2417 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2418 }
2419
2420 // LogTouchedMethods and PrintTouchedMethods
2421
2422 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2423 // the Method may be garbage collected. Let's roll our own hash table.
2424 class TouchedMethodRecord : CHeapObj<mtTracing> {
2425 public:
2426 // It's OK to store Symbols here because they will NOT be GC'ed if
2427 // LogTouchedMethods is enabled.
2428 TouchedMethodRecord* _next;
2429 Symbol* _class_name;
2430 Symbol* _method_name;
2431 Symbol* _method_signature;
2432 };
2433
2434 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2435 static TouchedMethodRecord** _touched_method_table = NULL;
2436
log_touched(Thread * current)2437 void Method::log_touched(Thread* current) {
2438
2439 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2440 Symbol* my_class = klass_name();
2441 Symbol* my_name = name();
2442 Symbol* my_sig = signature();
2443
2444 unsigned int hash = my_class->identity_hash() +
2445 my_name->identity_hash() +
2446 my_sig->identity_hash();
2447 juint index = juint(hash) % table_size;
2448
2449 MutexLocker ml(current, TouchedMethodLog_lock);
2450 if (_touched_method_table == NULL) {
2451 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2452 mtTracing, CURRENT_PC);
2453 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2454 }
2455
2456 TouchedMethodRecord* ptr = _touched_method_table[index];
2457 while (ptr) {
2458 if (ptr->_class_name == my_class &&
2459 ptr->_method_name == my_name &&
2460 ptr->_method_signature == my_sig) {
2461 return;
2462 }
2463 if (ptr->_next == NULL) break;
2464 ptr = ptr->_next;
2465 }
2466 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2467 my_class->increment_refcount();
2468 my_name->increment_refcount();
2469 my_sig->increment_refcount();
2470 nptr->_class_name = my_class;
2471 nptr->_method_name = my_name;
2472 nptr->_method_signature = my_sig;
2473 nptr->_next = NULL;
2474
2475 if (ptr == NULL) {
2476 // first
2477 _touched_method_table[index] = nptr;
2478 } else {
2479 ptr->_next = nptr;
2480 }
2481 }
2482
print_touched_methods(outputStream * out)2483 void Method::print_touched_methods(outputStream* out) {
2484 MutexLocker ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2485 out->print_cr("# Method::print_touched_methods version 1");
2486 if (_touched_method_table) {
2487 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2488 TouchedMethodRecord* ptr = _touched_method_table[i];
2489 while(ptr) {
2490 ptr->_class_name->print_symbol_on(out); out->print(".");
2491 ptr->_method_name->print_symbol_on(out); out->print(":");
2492 ptr->_method_signature->print_symbol_on(out); out->cr();
2493 ptr = ptr->_next;
2494 }
2495 }
2496 }
2497 }
2498
2499 // Verification
2500
verify_on(outputStream * st)2501 void Method::verify_on(outputStream* st) {
2502 guarantee(is_method(), "object must be method");
2503 guarantee(constants()->is_constantPool(), "should be constant pool");
2504 MethodData* md = method_data();
2505 guarantee(md == NULL ||
2506 md->is_methodData(), "should be method data");
2507 }
2508