1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/classLoaderDataGraph.hpp"
27 #include "classfile/metadataOnStackMark.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "code/codeCache.hpp"
30 #include "code/debugInfoRec.hpp"
31 #include "gc/shared/collectedHeap.inline.hpp"
32 #include "interpreter/bytecodeStream.hpp"
33 #include "interpreter/bytecodeTracer.hpp"
34 #include "interpreter/bytecodes.hpp"
35 #include "interpreter/interpreter.hpp"
36 #include "interpreter/oopMapCache.hpp"
37 #include "memory/allocation.inline.hpp"
38 #include "memory/heapInspection.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/metaspaceClosure.hpp"
41 #include "memory/metaspaceShared.hpp"
42 #include "memory/oopFactory.hpp"
43 #include "memory/resourceArea.hpp"
44 #include "oops/constMethod.hpp"
45 #include "oops/constantPool.hpp"
46 #include "oops/method.inline.hpp"
47 #include "oops/methodData.hpp"
48 #include "oops/objArrayOop.inline.hpp"
49 #include "oops/oop.inline.hpp"
50 #include "oops/symbol.hpp"
51 #include "prims/jvmtiExport.hpp"
52 #include "prims/methodHandles.hpp"
53 #include "prims/nativeLookup.hpp"
54 #include "runtime/arguments.hpp"
55 #include "runtime/compilationPolicy.hpp"
56 #include "runtime/frame.inline.hpp"
57 #include "runtime/handles.inline.hpp"
58 #include "runtime/init.hpp"
59 #include "runtime/orderAccess.hpp"
60 #include "runtime/relocator.hpp"
61 #include "runtime/safepointVerifiers.hpp"
62 #include "runtime/sharedRuntime.hpp"
63 #include "runtime/signature.hpp"
64 #include "utilities/align.hpp"
65 #include "utilities/quickSort.hpp"
66 #include "utilities/vmError.hpp"
67 #include "utilities/xmlstream.hpp"
68
69 // Implementation of Method
70
71 Method* Method::allocate(ClassLoaderData* loader_data,
72 int byte_code_size,
73 AccessFlags access_flags,
74 InlineTableSizes* sizes,
75 ConstMethod::MethodType method_type,
76 TRAPS) {
77 assert(!access_flags.is_native() || byte_code_size == 0,
78 "native methods should not contain byte codes");
79 ConstMethod* cm = ConstMethod::allocate(loader_data,
80 byte_code_size,
81 sizes,
82 method_type,
83 CHECK_NULL);
84 int size = Method::size(access_flags.is_native());
85 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
86 }
87
88 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
89 NoSafepointVerifier no_safepoint;
90 set_constMethod(xconst);
91 set_access_flags(access_flags);
92 set_intrinsic_id(vmIntrinsics::_none);
93 set_force_inline(false);
94 set_hidden(false);
95 set_dont_inline(false);
96 set_has_injected_profile(false);
97 set_method_data(NULL);
98 clear_method_counters();
99 set_vtable_index(Method::garbage_vtable_index);
100
101 // Fix and bury in Method*
102 set_interpreter_entry(NULL); // sets i2i entry and from_int
103 set_adapter_entry(NULL);
104 clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i
105
106 if (access_flags.is_native()) {
107 clear_native_function();
108 set_signature_handler(NULL);
109 }
110
111 NOT_PRODUCT(set_compiled_invocation_count(0);)
112 }
113
114 // Release Method*. The nmethod will be gone when we get here because
115 // we've walked the code cache.
116 void Method::deallocate_contents(ClassLoaderData* loader_data) {
117 MetadataFactory::free_metadata(loader_data, constMethod());
118 set_constMethod(NULL);
119 MetadataFactory::free_metadata(loader_data, method_data());
120 set_method_data(NULL);
121 MetadataFactory::free_metadata(loader_data, method_counters());
122 clear_method_counters();
123 // The nmethod will be gone when we get here.
124 if (code() != NULL) _code = NULL;
125 }
126
127 address Method::get_i2c_entry() {
128 assert(adapter() != NULL, "must have");
129 return adapter()->get_i2c_entry();
130 }
131
132 address Method::get_c2i_entry() {
133 assert(adapter() != NULL, "must have");
134 return adapter()->get_c2i_entry();
135 }
136
137 address Method::get_c2i_unverified_entry() {
138 assert(adapter() != NULL, "must have");
139 return adapter()->get_c2i_unverified_entry();
140 }
141
142 char* Method::name_and_sig_as_C_string() const {
143 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
144 }
145
146 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
147 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
148 }
149
150 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
151 const char* klass_name = klass->external_name();
152 int klass_name_len = (int)strlen(klass_name);
153 int method_name_len = method_name->utf8_length();
154 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
155 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
156 strcpy(dest, klass_name);
157 dest[klass_name_len] = '.';
158 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
159 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
160 dest[len] = 0;
161 return dest;
162 }
163
164 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
165 Symbol* klass_name = klass->name();
166 klass_name->as_klass_external_name(buf, size);
167 int len = (int)strlen(buf);
168
169 if (len < size - 1) {
170 buf[len++] = '.';
171
172 method_name->as_C_string(&(buf[len]), size - len);
173 len = (int)strlen(buf);
174
175 signature->as_C_string(&(buf[len]), size - len);
176 }
177
178 return buf;
179 }
180
181 const char* Method::external_name() const {
182 return external_name(constants()->pool_holder(), name(), signature());
183 }
184
185 void Method::print_external_name(outputStream *os) const {
186 print_external_name(os, constants()->pool_holder(), name(), signature());
187 }
188
189 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
190 stringStream ss;
191 print_external_name(&ss, klass, method_name, signature);
192 return ss.as_string();
193 }
194
195 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
196 signature->print_as_signature_external_return_type(os);
197 os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
198 signature->print_as_signature_external_parameters(os);
199 os->print(")");
200 }
201
202 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
203 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
204 // access exception table
205 ExceptionTable table(mh());
206 int length = table.length();
207 // iterate through all entries sequentially
208 constantPoolHandle pool(THREAD, mh->constants());
209 for (int i = 0; i < length; i ++) {
210 //reacquire the table in case a GC happened
211 ExceptionTable table(mh());
212 int beg_bci = table.start_pc(i);
213 int end_bci = table.end_pc(i);
214 assert(beg_bci <= end_bci, "inconsistent exception table");
215 if (beg_bci <= throw_bci && throw_bci < end_bci) {
216 // exception handler bci range covers throw_bci => investigate further
217 int handler_bci = table.handler_pc(i);
218 int klass_index = table.catch_type_index(i);
219 if (klass_index == 0) {
220 return handler_bci;
221 } else if (ex_klass == NULL) {
222 return handler_bci;
223 } else {
224 // we know the exception class => get the constraint class
225 // this may require loading of the constraint class; if verification
226 // fails or some other exception occurs, return handler_bci
227 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
228 assert(k != NULL, "klass not loaded");
229 if (ex_klass->is_subtype_of(k)) {
230 return handler_bci;
231 }
232 }
233 }
234 }
235
236 return -1;
237 }
238
239 void Method::mask_for(int bci, InterpreterOopMap* mask) {
240 methodHandle h_this(Thread::current(), this);
241 // Only GC uses the OopMapCache during thread stack root scanning
242 // any other uses generate an oopmap but do not save it in the cache.
243 if (Universe::heap()->is_gc_active()) {
244 method_holder()->mask_for(h_this, bci, mask);
245 } else {
246 OopMapCache::compute_one_oop_map(h_this, bci, mask);
247 }
248 return;
249 }
250
251
252 int Method::bci_from(address bcp) const {
253 if (is_native() && bcp == 0) {
254 return 0;
255 }
256 #ifdef ASSERT
257 {
258 ResourceMark rm;
259 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
260 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
261 p2i(bcp), name_and_sig_as_C_string());
262 }
263 #endif
264 return bcp - code_base();
265 }
266
267
268 int Method::validate_bci(int bci) const {
269 return (bci == 0 || bci < code_size()) ? bci : -1;
270 }
271
272 // Return bci if it appears to be a valid bcp
273 // Return -1 otherwise.
274 // Used by profiling code, when invalid data is a possibility.
275 // The caller is responsible for validating the Method* itself.
276 int Method::validate_bci_from_bcp(address bcp) const {
277 // keep bci as -1 if not a valid bci
278 int bci = -1;
279 if (bcp == 0 || bcp == code_base()) {
280 // code_size() may return 0 and we allow 0 here
281 // the method may be native
282 bci = 0;
283 } else if (contains(bcp)) {
284 bci = bcp - code_base();
285 }
286 // Assert that if we have dodged any asserts, bci is negative.
287 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
288 return bci;
289 }
290
291 address Method::bcp_from(int bci) const {
292 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
293 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
294 address bcp = code_base() + bci;
295 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
296 return bcp;
297 }
298
299 address Method::bcp_from(address bcp) const {
300 if (is_native() && bcp == NULL) {
301 return code_base();
302 } else {
303 return bcp;
304 }
305 }
306
307 int Method::size(bool is_native) {
308 // If native, then include pointers for native_function and signature_handler
309 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
310 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
311 return align_metadata_size(header_size() + extra_words);
312 }
313
314
315 Symbol* Method::klass_name() const {
316 return method_holder()->name();
317 }
318
319
320 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
321 log_trace(cds)("Iter(Method): %p", this);
322
323 it->push(&_constMethod);
324 it->push(&_method_data);
325 it->push(&_method_counters);
326 }
327
328 // Attempt to return method oop to original state. Clear any pointers
329 // (to objects outside the shared spaces). We won't be able to predict
330 // where they should point in a new JVM. Further initialize some
331 // entries now in order allow them to be write protected later.
332
333 void Method::remove_unshareable_info() {
334 unlink_method();
335 }
336
337 void Method::set_vtable_index(int index) {
338 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
339 // At runtime initialize_vtable is rerun as part of link_class_impl()
340 // for a shared class loaded by the non-boot loader to obtain the loader
341 // constraints based on the runtime classloaders' context.
342 return; // don't write into the shared class
343 } else {
344 _vtable_index = index;
345 }
346 }
347
348 void Method::set_itable_index(int index) {
349 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
350 // At runtime initialize_itable is rerun as part of link_class_impl()
351 // for a shared class loaded by the non-boot loader to obtain the loader
352 // constraints based on the runtime classloaders' context. The dumptime
353 // itable index should be the same as the runtime index.
354 assert(_vtable_index == itable_index_max - index,
355 "archived itable index is different from runtime index");
356 return; // don’t write into the shared class
357 } else {
358 _vtable_index = itable_index_max - index;
359 }
360 assert(valid_itable_index(), "");
361 }
362
363
364
365 bool Method::was_executed_more_than(int n) {
366 // Invocation counter is reset when the Method* is compiled.
367 // If the method has compiled code we therefore assume it has
368 // be excuted more than n times.
369 if (is_accessor() || is_empty_method() || (code() != NULL)) {
370 // interpreter doesn't bump invocation counter of trivial methods
371 // compiler does not bump invocation counter of compiled methods
372 return true;
373 }
374 else if ((method_counters() != NULL &&
375 method_counters()->invocation_counter()->carry()) ||
376 (method_data() != NULL &&
377 method_data()->invocation_counter()->carry())) {
378 // The carry bit is set when the counter overflows and causes
379 // a compilation to occur. We don't know how many times
380 // the counter has been reset, so we simply assume it has
381 // been executed more than n times.
382 return true;
383 } else {
384 return invocation_count() > n;
385 }
386 }
387
388 void Method::print_invocation_count() {
389 if (is_static()) tty->print("static ");
390 if (is_final()) tty->print("final ");
391 if (is_synchronized()) tty->print("synchronized ");
392 if (is_native()) tty->print("native ");
393 tty->print("%s::", method_holder()->external_name());
394 name()->print_symbol_on(tty);
395 signature()->print_symbol_on(tty);
396
397 if (WizardMode) {
398 // dump the size of the byte codes
399 tty->print(" {%d}", code_size());
400 }
401 tty->cr();
402
403 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count());
404 tty->print_cr (" invocation_counter: %8d ", invocation_count());
405 tty->print_cr (" backedge_counter: %8d ", backedge_count());
406 #ifndef PRODUCT
407 if (CountCompiledCalls) {
408 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count());
409 }
410 #endif
411 }
412
413 // Build a MethodData* object to hold information about this method
414 // collected in the interpreter.
415 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
416 // Do not profile the method if metaspace has hit an OOM previously
417 // allocating profiling data. Callers clear pending exception so don't
418 // add one here.
419 if (ClassLoaderDataGraph::has_metaspace_oom()) {
420 return;
421 }
422
423 // Grab a lock here to prevent multiple
424 // MethodData*s from being created.
425 MutexLocker ml(MethodData_lock, THREAD);
426 if (method->method_data() == NULL) {
427 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
428 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
429 if (HAS_PENDING_EXCEPTION) {
430 CompileBroker::log_metaspace_failure();
431 ClassLoaderDataGraph::set_metaspace_oom(true);
432 return; // return the exception (which is cleared)
433 }
434
435 method->set_method_data(method_data);
436 if (PrintMethodData && (Verbose || WizardMode)) {
437 ResourceMark rm(THREAD);
438 tty->print("build_interpreter_method_data for ");
439 method->print_name(tty);
440 tty->cr();
441 // At the end of the run, the MDO, full of data, will be dumped.
442 }
443 }
444 }
445
446 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
447 // Do not profile the method if metaspace has hit an OOM previously
448 if (ClassLoaderDataGraph::has_metaspace_oom()) {
449 return NULL;
450 }
451
452 methodHandle mh(m);
453 MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
454 if (HAS_PENDING_EXCEPTION) {
455 CompileBroker::log_metaspace_failure();
456 ClassLoaderDataGraph::set_metaspace_oom(true);
457 return NULL; // return the exception (which is cleared)
458 }
459 if (!mh->init_method_counters(counters)) {
460 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
461 }
462
463 if (LogTouchedMethods) {
464 mh->log_touched(CHECK_NULL);
465 }
466
467 return mh->method_counters();
468 }
469
470 bool Method::init_method_counters(MethodCounters* counters) {
471 // Try to install a pointer to MethodCounters, return true on success.
472 return Atomic::replace_if_null(counters, &_method_counters);
473 }
474
475 int Method::extra_stack_words() {
476 // not an inline function, to avoid a header dependency on Interpreter
477 return extra_stack_entries() * Interpreter::stackElementSize;
478 }
479
480
481 void Method::compute_size_of_parameters(Thread *thread) {
482 ArgumentSizeComputer asc(signature());
483 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
484 }
485
486 BasicType Method::result_type() const {
487 ResultTypeFinder rtf(signature());
488 return rtf.type();
489 }
490
491
492 bool Method::is_empty_method() const {
493 return code_size() == 1
494 && *code_base() == Bytecodes::_return;
495 }
496
497
498 bool Method::is_vanilla_constructor() const {
499 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
500 // which only calls the superclass vanilla constructor and possibly does stores of
501 // zero constants to local fields:
502 //
503 // aload_0
504 // invokespecial
505 // indexbyte1
506 // indexbyte2
507 //
508 // followed by an (optional) sequence of:
509 //
510 // aload_0
511 // aconst_null / iconst_0 / fconst_0 / dconst_0
512 // putfield
513 // indexbyte1
514 // indexbyte2
515 //
516 // followed by:
517 //
518 // return
519
520 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
521 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
522 int size = code_size();
523 // Check if size match
524 if (size == 0 || size % 5 != 0) return false;
525 address cb = code_base();
526 int last = size - 1;
527 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
528 // Does not call superclass default constructor
529 return false;
530 }
531 // Check optional sequence
532 for (int i = 4; i < last; i += 5) {
533 if (cb[i] != Bytecodes::_aload_0) return false;
534 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
535 if (cb[i+2] != Bytecodes::_putfield) return false;
536 }
537 return true;
538 }
539
540
541 bool Method::compute_has_loops_flag() {
542 BytecodeStream bcs(this);
543 Bytecodes::Code bc;
544
545 while ((bc = bcs.next()) >= 0) {
546 switch( bc ) {
547 case Bytecodes::_ifeq:
548 case Bytecodes::_ifnull:
549 case Bytecodes::_iflt:
550 case Bytecodes::_ifle:
551 case Bytecodes::_ifne:
552 case Bytecodes::_ifnonnull:
553 case Bytecodes::_ifgt:
554 case Bytecodes::_ifge:
555 case Bytecodes::_if_icmpeq:
556 case Bytecodes::_if_icmpne:
557 case Bytecodes::_if_icmplt:
558 case Bytecodes::_if_icmpgt:
559 case Bytecodes::_if_icmple:
560 case Bytecodes::_if_icmpge:
561 case Bytecodes::_if_acmpeq:
562 case Bytecodes::_if_acmpne:
563 case Bytecodes::_goto:
564 case Bytecodes::_jsr:
565 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
566 break;
567
568 case Bytecodes::_goto_w:
569 case Bytecodes::_jsr_w:
570 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
571 break;
572
573 default:
574 break;
575 }
576 }
577 _access_flags.set_loops_flag_init();
578 return _access_flags.has_loops();
579 }
580
581 bool Method::is_final_method(AccessFlags class_access_flags) const {
582 // or "does_not_require_vtable_entry"
583 // default method or overpass can occur, is not final (reuses vtable entry)
584 // private methods in classes get vtable entries for backward class compatibility.
585 if (is_overpass() || is_default_method()) return false;
586 return is_final() || class_access_flags.is_final();
587 }
588
589 bool Method::is_final_method() const {
590 return is_final_method(method_holder()->access_flags());
591 }
592
593 bool Method::is_default_method() const {
594 if (method_holder() != NULL &&
595 method_holder()->is_interface() &&
596 !is_abstract() && !is_private()) {
597 return true;
598 } else {
599 return false;
600 }
601 }
602
603 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
604 if (is_final_method(class_access_flags)) return true;
605 #ifdef ASSERT
606 ResourceMark rm;
607 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
608 if (class_access_flags.is_interface()) {
609 assert(is_nonv == is_static() || is_nonv == is_private(),
610 "nonvirtual unexpected for non-static, non-private: %s",
611 name_and_sig_as_C_string());
612 }
613 #endif
614 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
615 return vtable_index() == nonvirtual_vtable_index;
616 }
617
618 bool Method::can_be_statically_bound() const {
619 return can_be_statically_bound(method_holder()->access_flags());
620 }
621
622 bool Method::is_accessor() const {
623 return is_getter() || is_setter();
624 }
625
626 bool Method::is_getter() const {
627 if (code_size() != 5) return false;
628 if (size_of_parameters() != 1) return false;
629 if (java_code_at(0) != Bytecodes::_aload_0) return false;
630 if (java_code_at(1) != Bytecodes::_getfield) return false;
631 switch (java_code_at(4)) {
632 case Bytecodes::_ireturn:
633 case Bytecodes::_lreturn:
634 case Bytecodes::_freturn:
635 case Bytecodes::_dreturn:
636 case Bytecodes::_areturn:
637 break;
638 default:
639 return false;
640 }
641 return true;
642 }
643
644 bool Method::is_setter() const {
645 if (code_size() != 6) return false;
646 if (java_code_at(0) != Bytecodes::_aload_0) return false;
647 switch (java_code_at(1)) {
648 case Bytecodes::_iload_1:
649 case Bytecodes::_aload_1:
650 case Bytecodes::_fload_1:
651 if (size_of_parameters() != 2) return false;
652 break;
653 case Bytecodes::_dload_1:
654 case Bytecodes::_lload_1:
655 if (size_of_parameters() != 3) return false;
656 break;
657 default:
658 return false;
659 }
660 if (java_code_at(2) != Bytecodes::_putfield) return false;
661 if (java_code_at(5) != Bytecodes::_return) return false;
662 return true;
663 }
664
665 bool Method::is_constant_getter() const {
666 int last_index = code_size() - 1;
667 // Check if the first 1-3 bytecodes are a constant push
668 // and the last bytecode is a return.
669 return (2 <= code_size() && code_size() <= 4 &&
670 Bytecodes::is_const(java_code_at(0)) &&
671 Bytecodes::length_for(java_code_at(0)) == last_index &&
672 Bytecodes::is_return(java_code_at(last_index)));
673 }
674
675 bool Method::is_initializer() const {
676 return is_object_initializer() || is_static_initializer();
677 }
678
679 bool Method::has_valid_initializer_flags() const {
680 return (is_static() ||
681 method_holder()->major_version() < 51);
682 }
683
684 bool Method::is_static_initializer() const {
685 // For classfiles version 51 or greater, ensure that the clinit method is
686 // static. Non-static methods with the name "<clinit>" are not static
687 // initializers. (older classfiles exempted for backward compatibility)
688 return name() == vmSymbols::class_initializer_name() &&
689 has_valid_initializer_flags();
690 }
691
692 bool Method::is_object_initializer() const {
693 return name() == vmSymbols::object_initializer_name();
694 }
695
696 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
697 int length = method->checked_exceptions_length();
698 if (length == 0) { // common case
699 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
700 } else {
701 methodHandle h_this(THREAD, method);
702 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
703 objArrayHandle mirrors (THREAD, m_oop);
704 for (int i = 0; i < length; i++) {
705 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
706 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
707 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
708 mirrors->obj_at_put(i, k->java_mirror());
709 }
710 return mirrors;
711 }
712 };
713
714
715 int Method::line_number_from_bci(int bci) const {
716 int best_bci = 0;
717 int best_line = -1;
718 if (bci == SynchronizationEntryBCI) bci = 0;
719 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
720 // The line numbers are a short array of 2-tuples [start_pc, line_number].
721 // Not necessarily sorted and not necessarily one-to-one.
722 CompressedLineNumberReadStream stream(compressed_linenumber_table());
723 while (stream.read_pair()) {
724 if (stream.bci() == bci) {
725 // perfect match
726 return stream.line();
727 } else {
728 // update best_bci/line
729 if (stream.bci() < bci && stream.bci() >= best_bci) {
730 best_bci = stream.bci();
731 best_line = stream.line();
732 }
733 }
734 }
735 }
736 return best_line;
737 }
738
739
740 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
741 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
742 Thread *thread = Thread::current();
743 Symbol* klass_name = constants()->klass_name_at(klass_index);
744 Handle loader(thread, method_holder()->class_loader());
745 Handle prot (thread, method_holder()->protection_domain());
746 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
747 } else {
748 return true;
749 }
750 }
751
752
753 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
754 int klass_index = constants()->klass_ref_index_at(refinfo_index);
755 if (must_be_resolved) {
756 // Make sure klass is resolved in constantpool.
757 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
758 }
759 return is_klass_loaded_by_klass_index(klass_index);
760 }
761
762
763 void Method::set_native_function(address function, bool post_event_flag) {
764 assert(function != NULL, "use clear_native_function to unregister natives");
765 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
766 address* native_function = native_function_addr();
767
768 // We can see racers trying to place the same native function into place. Once
769 // is plenty.
770 address current = *native_function;
771 if (current == function) return;
772 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
773 function != NULL) {
774 // native_method_throw_unsatisfied_link_error_entry() should only
775 // be passed when post_event_flag is false.
776 assert(function !=
777 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
778 "post_event_flag mis-match");
779
780 // post the bind event, and possible change the bind function
781 JvmtiExport::post_native_method_bind(this, &function);
782 }
783 *native_function = function;
784 // This function can be called more than once. We must make sure that we always
785 // use the latest registered method -> check if a stub already has been generated.
786 // If so, we have to make it not_entrant.
787 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
788 if (nm != NULL) {
789 nm->make_not_entrant();
790 }
791 }
792
793
794 bool Method::has_native_function() const {
795 if (is_method_handle_intrinsic())
796 return false; // special-cased in SharedRuntime::generate_native_wrapper
797 address func = native_function();
798 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
799 }
800
801
802 void Method::clear_native_function() {
803 // Note: is_method_handle_intrinsic() is allowed here.
804 set_native_function(
805 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
806 !native_bind_event_is_interesting);
807 clear_code();
808 }
809
810 address Method::critical_native_function() {
811 methodHandle mh(this);
812 return NativeLookup::lookup_critical_entry(mh);
813 }
814
815
816 void Method::set_signature_handler(address handler) {
817 address* signature_handler = signature_handler_addr();
818 *signature_handler = handler;
819 }
820
821
822 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
823 if (PrintCompilation && report) {
824 ttyLocker ttyl;
825 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
826 if (comp_level == CompLevel_all) {
827 tty->print("all levels ");
828 } else {
829 tty->print("levels ");
830 for (int i = (int)CompLevel_none; i <= comp_level; i++) {
831 tty->print("%d ", i);
832 }
833 }
834 this->print_short_name(tty);
835 int size = this->code_size();
836 if (size > 0) {
837 tty->print(" (%d bytes)", size);
838 }
839 if (reason != NULL) {
840 tty->print(" %s", reason);
841 }
842 tty->cr();
843 }
844 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
845 ttyLocker ttyl;
846 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
847 os::current_thread_id(), is_osr, comp_level);
848 if (reason != NULL) {
849 xtty->print(" reason=\'%s\'", reason);
850 }
851 xtty->method(this);
852 xtty->stamp();
853 xtty->end_elem();
854 }
855 }
856
857 bool Method::is_always_compilable() const {
858 // Generated adapters must be compiled
859 if (is_method_handle_intrinsic() && is_synthetic()) {
860 assert(!is_not_c1_compilable(), "sanity check");
861 assert(!is_not_c2_compilable(), "sanity check");
862 return true;
863 }
864
865 return false;
866 }
867
868 bool Method::is_not_compilable(int comp_level) const {
869 if (number_of_breakpoints() > 0)
870 return true;
871 if (is_always_compilable())
872 return false;
873 if (comp_level == CompLevel_any)
874 return is_not_c1_compilable() || is_not_c2_compilable();
875 if (is_c1_compile(comp_level))
876 return is_not_c1_compilable();
877 if (is_c2_compile(comp_level))
878 return is_not_c2_compilable();
879 return false;
880 }
881
882 // call this when compiler finds that this method is not compilable
883 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
884 if (is_always_compilable()) {
885 // Don't mark a method which should be always compilable
886 return;
887 }
888 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
889 if (comp_level == CompLevel_all) {
890 set_not_c1_compilable();
891 set_not_c2_compilable();
892 } else {
893 if (is_c1_compile(comp_level))
894 set_not_c1_compilable();
895 if (is_c2_compile(comp_level))
896 set_not_c2_compilable();
897 }
898 CompilationPolicy::policy()->disable_compilation(this);
899 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
900 }
901
902 bool Method::is_not_osr_compilable(int comp_level) const {
903 if (is_not_compilable(comp_level))
904 return true;
905 if (comp_level == CompLevel_any)
906 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
907 if (is_c1_compile(comp_level))
908 return is_not_c1_osr_compilable();
909 if (is_c2_compile(comp_level))
910 return is_not_c2_osr_compilable();
911 return false;
912 }
913
914 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
915 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
916 if (comp_level == CompLevel_all) {
917 set_not_c1_osr_compilable();
918 set_not_c2_osr_compilable();
919 } else {
920 if (is_c1_compile(comp_level))
921 set_not_c1_osr_compilable();
922 if (is_c2_compile(comp_level))
923 set_not_c2_osr_compilable();
924 }
925 CompilationPolicy::policy()->disable_compilation(this);
926 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
927 }
928
929 // Revert to using the interpreter and clear out the nmethod
930 void Method::clear_code(bool acquire_lock /* = true */) {
931 MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
932 // this may be NULL if c2i adapters have not been made yet
933 // Only should happen at allocate time.
934 if (adapter() == NULL) {
935 _from_compiled_entry = NULL;
936 } else {
937 _from_compiled_entry = adapter()->get_c2i_entry();
938 }
939 OrderAccess::storestore();
940 _from_interpreted_entry = _i2i_entry;
941 OrderAccess::storestore();
942 _code = NULL;
943 }
944
945 #if INCLUDE_CDS
946 // Called by class data sharing to remove any entry points (which are not shared)
947 void Method::unlink_method() {
948 _code = NULL;
949
950 assert(DumpSharedSpaces, "dump time only");
951 // Set the values to what they should be at run time. Note that
952 // this Method can no longer be executed during dump time.
953 _i2i_entry = Interpreter::entry_for_cds_method(this);
954 _from_interpreted_entry = _i2i_entry;
955
956 if (is_native()) {
957 *native_function_addr() = NULL;
958 set_signature_handler(NULL);
959 }
960 NOT_PRODUCT(set_compiled_invocation_count(0);)
961
962 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
963 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
964 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
965 assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
966
967 set_method_data(NULL);
968 clear_method_counters();
969 }
970 #endif
971
972 /****************************************************************************
973 // The following illustrates how the entries work for CDS shared Methods:
974 //
975 // Our goal is to delay writing into a shared Method until it's compiled.
976 // Hence, we want to determine the initial values for _i2i_entry,
977 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
978 //
979 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
980 // They also have similar signatures so that they will share the same
981 // AdapterHandlerEntry.
982 //
983 // _adapter_trampoline points to a fixed location in the RW section of
984 // the CDS archive. This location initially contains a NULL pointer. When the
985 // first of method A or B is linked, an AdapterHandlerEntry is allocated
986 // dynamically, and its c2i/i2c entries are generated.
987 //
988 // _i2i_entry and _from_interpreted_entry initially points to the same
989 // (fixed) location in the CODE section of the CDS archive. This contains
990 // an unconditional branch to the actual entry for "zero_locals", which is
991 // generated at run time and may be on an arbitrary address. Thus, the
992 // unconditional branch is also generated at run time to jump to the correct
993 // address.
994 //
995 // Similarly, _from_compiled_entry points to a fixed address in the CODE
996 // section. This address has enough space for an unconditional branch
997 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
998 // initialized, and the address for the actual c2i_entry is known, we emit a
999 // branch instruction here to branch to the actual c2i_entry.
1000 //
1001 // The effect of the extra branch on the i2i and c2i entries is negligible.
1002 //
1003 // The reason for putting _adapter_trampoline in RO is many shared Methods
1004 // share the same AdapterHandlerEntry, so we can save space in the RW section
1005 // by having the extra indirection.
1006
1007
1008 [Method A: RW]
1009 _constMethod ----> [ConstMethod: RO]
1010 _adapter_trampoline -----------+
1011 |
1012 _i2i_entry (same value as method B) |
1013 _from_interpreted_entry (same value as method B) |
1014 _from_compiled_entry (same value as method B) |
1015 |
1016 |
1017 [Method B: RW] +--------+
1018 _constMethod ----> [ConstMethod: RO] |
1019 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1020 |
1021 +-------------------------------+
1022 |
1023 +----> [AdapterHandlerEntry] (allocated at run time)
1024 _fingerprint
1025 _c2i_entry ---------------------------------+->[c2i entry..]
1026 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1027 _from_interpreted_entry | _c2i_unverified_entry | |
1028 | | | |
1029 | | (_cds_entry_table: CODE) | |
1030 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1031 | | (allocated at run time) | |
1032 | | ... [asm code ...] | |
1033 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1034 | | |
1035 | | |
1036 +-[compiled]-------------------------------------------------------------------+ |
1037 |
1038 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1039 [jmp c2i_entry] ------------------------------------------------------+
1040
1041 ***/
1042
1043 // Called when the method_holder is getting linked. Setup entrypoints so the method
1044 // is ready to be called from interpreter, compiler, and vtables.
1045 void Method::link_method(const methodHandle& h_method, TRAPS) {
1046 // If the code cache is full, we may reenter this function for the
1047 // leftover methods that weren't linked.
1048 if (is_shared()) {
1049 address entry = Interpreter::entry_for_cds_method(h_method);
1050 assert(entry != NULL && entry == _i2i_entry,
1051 "should be correctly set during dump time");
1052 if (adapter() != NULL) {
1053 return;
1054 }
1055 assert(entry == _from_interpreted_entry,
1056 "should be correctly set during dump time");
1057 } else if (_i2i_entry != NULL) {
1058 return;
1059 }
1060 assert( _code == NULL, "nothing compiled yet" );
1061
1062 // Setup interpreter entrypoint
1063 assert(this == h_method(), "wrong h_method()" );
1064
1065 if (!is_shared()) {
1066 assert(adapter() == NULL, "init'd to NULL");
1067 address entry = Interpreter::entry_for_method(h_method);
1068 assert(entry != NULL, "interpreter entry must be non-null");
1069 // Sets both _i2i_entry and _from_interpreted_entry
1070 set_interpreter_entry(entry);
1071 }
1072
1073 // Don't overwrite already registered native entries.
1074 if (is_native() && !has_native_function()) {
1075 set_native_function(
1076 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1077 !native_bind_event_is_interesting);
1078 }
1079
1080 // Setup compiler entrypoint. This is made eagerly, so we do not need
1081 // special handling of vtables. An alternative is to make adapters more
1082 // lazily by calling make_adapter() from from_compiled_entry() for the
1083 // normal calls. For vtable calls life gets more complicated. When a
1084 // call-site goes mega-morphic we need adapters in all methods which can be
1085 // called from the vtable. We need adapters on such methods that get loaded
1086 // later. Ditto for mega-morphic itable calls. If this proves to be a
1087 // problem we'll make these lazily later.
1088 (void) make_adapters(h_method, CHECK);
1089
1090 // ONLY USE the h_method now as make_adapter may have blocked
1091
1092 }
1093
1094 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1095 // Adapters for compiled code are made eagerly here. They are fairly
1096 // small (generally < 100 bytes) and quick to make (and cached and shared)
1097 // so making them eagerly shouldn't be too expensive.
1098 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1099 if (adapter == NULL ) {
1100 if (!is_init_completed()) {
1101 // Don't throw exceptions during VM initialization because java.lang.* classes
1102 // might not have been initialized, causing problems when constructing the
1103 // Java exception object.
1104 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1105 } else {
1106 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1107 }
1108 }
1109
1110 if (mh->is_shared()) {
1111 assert(mh->adapter() == adapter, "must be");
1112 assert(mh->_from_compiled_entry != NULL, "must be");
1113 } else {
1114 mh->set_adapter_entry(adapter);
1115 mh->_from_compiled_entry = adapter->get_c2i_entry();
1116 }
1117 return adapter->get_c2i_entry();
1118 }
1119
1120 void Method::restore_unshareable_info(TRAPS) {
1121 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1122
1123 // Since restore_unshareable_info can be called more than once for a method, don't
1124 // redo any work.
1125 if (adapter() == NULL) {
1126 methodHandle mh(THREAD, this);
1127 link_method(mh, CHECK);
1128 }
1129 }
1130
1131 address Method::from_compiled_entry_no_trampoline() const {
1132 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1133 if (code) {
1134 return code->verified_entry_point();
1135 } else {
1136 return adapter()->get_c2i_entry();
1137 }
1138 }
1139
1140 // The verified_code_entry() must be called when a invoke is resolved
1141 // on this method.
1142
1143 // It returns the compiled code entry point, after asserting not null.
1144 // This function is called after potential safepoints so that nmethod
1145 // or adapter that it points to is still live and valid.
1146 // This function must not hit a safepoint!
1147 address Method::verified_code_entry() {
1148 debug_only(NoSafepointVerifier nsv;)
1149 assert(_from_compiled_entry != NULL, "must be set");
1150 return _from_compiled_entry;
1151 }
1152
1153 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1154 // (could be racing a deopt).
1155 // Not inline to avoid circular ref.
1156 bool Method::check_code() const {
1157 // cached in a register or local. There's a race on the value of the field.
1158 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1159 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1160 }
1161
1162 // Install compiled code. Instantly it can execute.
1163 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1164 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1165 assert( code, "use clear_code to remove code" );
1166 assert( mh->check_code(), "" );
1167
1168 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1169
1170 // These writes must happen in this order, because the interpreter will
1171 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1172 // which jumps to _from_compiled_entry.
1173 mh->_code = code; // Assign before allowing compiled code to exec
1174
1175 int comp_level = code->comp_level();
1176 // In theory there could be a race here. In practice it is unlikely
1177 // and not worth worrying about.
1178 if (comp_level > mh->highest_comp_level()) {
1179 mh->set_highest_comp_level(comp_level);
1180 }
1181
1182 OrderAccess::storestore();
1183 mh->_from_compiled_entry = code->verified_entry_point();
1184 OrderAccess::storestore();
1185 // Instantly compiled code can execute.
1186 if (!mh->is_method_handle_intrinsic())
1187 mh->_from_interpreted_entry = mh->get_i2c_entry();
1188 }
1189
1190
1191 bool Method::is_overridden_in(Klass* k) const {
1192 InstanceKlass* ik = InstanceKlass::cast(k);
1193
1194 if (ik->is_interface()) return false;
1195
1196 // If method is an interface, we skip it - except if it
1197 // is a miranda method
1198 if (method_holder()->is_interface()) {
1199 // Check that method is not a miranda method
1200 if (ik->lookup_method(name(), signature()) == NULL) {
1201 // No implementation exist - so miranda method
1202 return false;
1203 }
1204 return true;
1205 }
1206
1207 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1208 if (!has_vtable_index()) {
1209 return false;
1210 } else {
1211 Method* vt_m = ik->method_at_vtable(vtable_index());
1212 return vt_m != this;
1213 }
1214 }
1215
1216
1217 // give advice about whether this Method* should be cached or not
1218 bool Method::should_not_be_cached() const {
1219 if (is_old()) {
1220 // This method has been redefined. It is either EMCP or obsolete
1221 // and we don't want to cache it because that would pin the method
1222 // down and prevent it from being collectible if and when it
1223 // finishes executing.
1224 return true;
1225 }
1226
1227 // caching this method should be just fine
1228 return false;
1229 }
1230
1231
1232 /**
1233 * Returns true if this is one of the specially treated methods for
1234 * security related stack walks (like Reflection.getCallerClass).
1235 */
1236 bool Method::is_ignored_by_security_stack_walk() const {
1237 if (intrinsic_id() == vmIntrinsics::_invoke) {
1238 // This is Method.invoke() -- ignore it
1239 return true;
1240 }
1241 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1242 // This is an auxilary frame -- ignore it
1243 return true;
1244 }
1245 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1246 // This is an internal adapter frame for method handles -- ignore it
1247 return true;
1248 }
1249 return false;
1250 }
1251
1252
1253 // Constant pool structure for invoke methods:
1254 enum {
1255 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1256 _imcp_invoke_signature, // utf8: (variable Symbol*)
1257 _imcp_limit
1258 };
1259
1260 // Test if this method is an MH adapter frame generated by Java code.
1261 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1262 bool Method::is_compiled_lambda_form() const {
1263 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1264 }
1265
1266 // Test if this method is an internal MH primitive method.
1267 bool Method::is_method_handle_intrinsic() const {
1268 vmIntrinsics::ID iid = intrinsic_id();
1269 return (MethodHandles::is_signature_polymorphic(iid) &&
1270 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1271 }
1272
1273 bool Method::has_member_arg() const {
1274 vmIntrinsics::ID iid = intrinsic_id();
1275 return (MethodHandles::is_signature_polymorphic(iid) &&
1276 MethodHandles::has_member_arg(iid));
1277 }
1278
1279 // Make an instance of a signature-polymorphic internal MH primitive.
1280 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1281 Symbol* signature,
1282 TRAPS) {
1283 ResourceMark rm;
1284 methodHandle empty;
1285
1286 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1287 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1288 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1289 if (TraceMethodHandles) {
1290 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1291 }
1292
1293 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1294 name->increment_refcount();
1295 signature->increment_refcount();
1296
1297 int cp_length = _imcp_limit;
1298 ClassLoaderData* loader_data = holder->class_loader_data();
1299 constantPoolHandle cp;
1300 {
1301 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1302 cp = constantPoolHandle(THREAD, cp_oop);
1303 }
1304 cp->set_pool_holder(holder);
1305 cp->symbol_at_put(_imcp_invoke_name, name);
1306 cp->symbol_at_put(_imcp_invoke_signature, signature);
1307 cp->set_has_preresolution();
1308
1309 // decide on access bits: public or not?
1310 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1311 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1312 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1313 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1314
1315 methodHandle m;
1316 {
1317 InlineTableSizes sizes;
1318 Method* m_oop = Method::allocate(loader_data, 0,
1319 accessFlags_from(flags_bits), &sizes,
1320 ConstMethod::NORMAL, CHECK_(empty));
1321 m = methodHandle(THREAD, m_oop);
1322 }
1323 m->set_constants(cp());
1324 m->set_name_index(_imcp_invoke_name);
1325 m->set_signature_index(_imcp_invoke_signature);
1326 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1327 assert(m->signature() == signature, "");
1328 ResultTypeFinder rtf(signature);
1329 m->constMethod()->set_result_type(rtf.type());
1330 m->compute_size_of_parameters(THREAD);
1331 m->init_intrinsic_id();
1332 assert(m->is_method_handle_intrinsic(), "");
1333 #ifdef ASSERT
1334 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1335 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1336 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1337 #endif //ASSERT
1338
1339 // Finally, set up its entry points.
1340 assert(m->can_be_statically_bound(), "");
1341 m->set_vtable_index(Method::nonvirtual_vtable_index);
1342 m->link_method(m, CHECK_(empty));
1343
1344 if (TraceMethodHandles && (Verbose || WizardMode)) {
1345 ttyLocker ttyl;
1346 m->print_on(tty);
1347 }
1348
1349 return m;
1350 }
1351
1352 Klass* Method::check_non_bcp_klass(Klass* klass) {
1353 if (klass != NULL && klass->class_loader() != NULL) {
1354 if (klass->is_objArray_klass())
1355 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1356 return klass;
1357 }
1358 return NULL;
1359 }
1360
1361
1362 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1363 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1364 // Code below does not work for native methods - they should never get rewritten anyway
1365 assert(!m->is_native(), "cannot rewrite native methods");
1366 // Allocate new Method*
1367 AccessFlags flags = m->access_flags();
1368
1369 ConstMethod* cm = m->constMethod();
1370 int checked_exceptions_len = cm->checked_exceptions_length();
1371 int localvariable_len = cm->localvariable_table_length();
1372 int exception_table_len = cm->exception_table_length();
1373 int method_parameters_len = cm->method_parameters_length();
1374 int method_annotations_len = cm->method_annotations_length();
1375 int parameter_annotations_len = cm->parameter_annotations_length();
1376 int type_annotations_len = cm->type_annotations_length();
1377 int default_annotations_len = cm->default_annotations_length();
1378
1379 InlineTableSizes sizes(
1380 localvariable_len,
1381 new_compressed_linenumber_size,
1382 exception_table_len,
1383 checked_exceptions_len,
1384 method_parameters_len,
1385 cm->generic_signature_index(),
1386 method_annotations_len,
1387 parameter_annotations_len,
1388 type_annotations_len,
1389 default_annotations_len,
1390 0);
1391
1392 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1393 Method* newm_oop = Method::allocate(loader_data,
1394 new_code_length,
1395 flags,
1396 &sizes,
1397 m->method_type(),
1398 CHECK_(methodHandle()));
1399 methodHandle newm (THREAD, newm_oop);
1400
1401 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1402 ConstMethod* newcm = newm->constMethod();
1403 int new_const_method_size = newm->constMethod()->size();
1404
1405 // This works because the source and target are both Methods. Some compilers
1406 // (e.g., clang) complain that the target vtable pointer will be stomped,
1407 // so cast away newm()'s and m()'s Methodness.
1408 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1409
1410 // Create shallow copy of ConstMethod.
1411 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1412
1413 // Reset correct method/const method, method size, and parameter info
1414 newm->set_constMethod(newcm);
1415 newm->constMethod()->set_code_size(new_code_length);
1416 newm->constMethod()->set_constMethod_size(new_const_method_size);
1417 assert(newm->code_size() == new_code_length, "check");
1418 assert(newm->method_parameters_length() == method_parameters_len, "check");
1419 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1420 assert(newm->exception_table_length() == exception_table_len, "check");
1421 assert(newm->localvariable_table_length() == localvariable_len, "check");
1422 // Copy new byte codes
1423 memcpy(newm->code_base(), new_code, new_code_length);
1424 // Copy line number table
1425 if (new_compressed_linenumber_size > 0) {
1426 memcpy(newm->compressed_linenumber_table(),
1427 new_compressed_linenumber_table,
1428 new_compressed_linenumber_size);
1429 }
1430 // Copy method_parameters
1431 if (method_parameters_len > 0) {
1432 memcpy(newm->method_parameters_start(),
1433 m->method_parameters_start(),
1434 method_parameters_len * sizeof(MethodParametersElement));
1435 }
1436 // Copy checked_exceptions
1437 if (checked_exceptions_len > 0) {
1438 memcpy(newm->checked_exceptions_start(),
1439 m->checked_exceptions_start(),
1440 checked_exceptions_len * sizeof(CheckedExceptionElement));
1441 }
1442 // Copy exception table
1443 if (exception_table_len > 0) {
1444 memcpy(newm->exception_table_start(),
1445 m->exception_table_start(),
1446 exception_table_len * sizeof(ExceptionTableElement));
1447 }
1448 // Copy local variable number table
1449 if (localvariable_len > 0) {
1450 memcpy(newm->localvariable_table_start(),
1451 m->localvariable_table_start(),
1452 localvariable_len * sizeof(LocalVariableTableElement));
1453 }
1454 // Copy stackmap table
1455 if (m->has_stackmap_table()) {
1456 int code_attribute_length = m->stackmap_data()->length();
1457 Array<u1>* stackmap_data =
1458 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1459 memcpy((void*)stackmap_data->adr_at(0),
1460 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1461 newm->set_stackmap_data(stackmap_data);
1462 }
1463
1464 // copy annotations over to new method
1465 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1466 return newm;
1467 }
1468
1469 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1470 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1471 // because we are not loading from core libraries
1472 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1473 // which does not use the class default class loader so we check for its loader here
1474 const InstanceKlass* ik = InstanceKlass::cast(holder);
1475 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1476 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1477 }
1478
1479 // see if the klass name is well-known:
1480 Symbol* klass_name = ik->name();
1481 return vmSymbols::find_sid(klass_name);
1482 }
1483
1484 void Method::init_intrinsic_id() {
1485 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1486 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1487 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1488 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1489
1490 // the klass name is well-known:
1491 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1492 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1493
1494 // ditto for method and signature:
1495 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1496 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1497 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1498 && name_id == vmSymbols::NO_SID) {
1499 return;
1500 }
1501 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1502 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1503 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1504 && sig_id == vmSymbols::NO_SID) {
1505 return;
1506 }
1507 jshort flags = access_flags().as_short();
1508
1509 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1510 if (id != vmIntrinsics::_none) {
1511 set_intrinsic_id(id);
1512 if (id == vmIntrinsics::_Class_cast) {
1513 // Even if the intrinsic is rejected, we want to inline this simple method.
1514 set_force_inline(true);
1515 }
1516 return;
1517 }
1518
1519 // A few slightly irregular cases:
1520 switch (klass_id) {
1521 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1522 // Second chance: check in regular Math.
1523 switch (name_id) {
1524 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1525 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1526 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1527 // pretend it is the corresponding method in the non-strict class:
1528 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1529 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1530 break;
1531 default:
1532 break;
1533 }
1534 break;
1535
1536 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1537 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1538 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1539 if (!is_native()) break;
1540 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1541 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1542 id = vmIntrinsics::_none;
1543 break;
1544
1545 default:
1546 break;
1547 }
1548
1549 if (id != vmIntrinsics::_none) {
1550 // Set up its iid. It is an alias method.
1551 set_intrinsic_id(id);
1552 return;
1553 }
1554 }
1555
1556 // These two methods are static since a GC may move the Method
1557 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1558 if (!THREAD->can_call_java()) {
1559 // There is nothing useful this routine can do from within the Compile thread.
1560 // Hopefully, the signature contains only well-known classes.
1561 // We could scan for this and return true/false, but the caller won't care.
1562 return false;
1563 }
1564 bool sig_is_loaded = true;
1565 Handle class_loader(THREAD, m->method_holder()->class_loader());
1566 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1567 ResourceMark rm(THREAD);
1568 Symbol* signature = m->signature();
1569 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1570 if (ss.is_object()) {
1571 Symbol* sym = ss.as_symbol(CHECK_(false));
1572 Symbol* name = sym;
1573 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1574 protection_domain, THREAD);
1575 // We are loading classes eagerly. If a ClassNotFoundException or
1576 // a LinkageError was generated, be sure to ignore it.
1577 if (HAS_PENDING_EXCEPTION) {
1578 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1579 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1580 CLEAR_PENDING_EXCEPTION;
1581 } else {
1582 return false;
1583 }
1584 }
1585 if( klass == NULL) { sig_is_loaded = false; }
1586 }
1587 }
1588 return sig_is_loaded;
1589 }
1590
1591 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1592 Handle class_loader(THREAD, m->method_holder()->class_loader());
1593 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1594 ResourceMark rm(THREAD);
1595 Symbol* signature = m->signature();
1596 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1597 if (ss.type() == T_OBJECT) {
1598 Symbol* name = ss.as_symbol_or_null();
1599 if (name == NULL) return true;
1600 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1601 if (klass == NULL) return true;
1602 }
1603 }
1604 return false;
1605 }
1606
1607 // Exposed so field engineers can debug VM
1608 void Method::print_short_name(outputStream* st) {
1609 ResourceMark rm;
1610 #ifdef PRODUCT
1611 st->print(" %s::", method_holder()->external_name());
1612 #else
1613 st->print(" %s::", method_holder()->internal_name());
1614 #endif
1615 name()->print_symbol_on(st);
1616 if (WizardMode) signature()->print_symbol_on(st);
1617 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1618 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1619 }
1620
1621 // Comparer for sorting an object array containing
1622 // Method*s.
1623 static int method_comparator(Method* a, Method* b) {
1624 return a->name()->fast_compare(b->name());
1625 }
1626
1627 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1628 // default_methods also uses this without the ordering for fast find_method
1629 void Method::sort_methods(Array<Method*>* methods, bool set_idnums) {
1630 int length = methods->length();
1631 if (length > 1) {
1632 {
1633 NoSafepointVerifier nsv;
1634 QuickSort::sort(methods->data(), length, method_comparator, /*idempotent=*/false);
1635 }
1636 // Reset method ordering
1637 if (set_idnums) {
1638 for (int i = 0; i < length; i++) {
1639 Method* m = methods->at(i);
1640 m->set_method_idnum(i);
1641 m->set_orig_method_idnum(i);
1642 }
1643 }
1644 }
1645 }
1646
1647 //-----------------------------------------------------------------------------------
1648 // Non-product code unless JVM/TI needs it
1649
1650 #if !defined(PRODUCT) || INCLUDE_JVMTI
1651 class SignatureTypePrinter : public SignatureTypeNames {
1652 private:
1653 outputStream* _st;
1654 bool _use_separator;
1655
1656 void type_name(const char* name) {
1657 if (_use_separator) _st->print(", ");
1658 _st->print("%s", name);
1659 _use_separator = true;
1660 }
1661
1662 public:
1663 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1664 _st = st;
1665 _use_separator = false;
1666 }
1667
1668 void print_parameters() { _use_separator = false; iterate_parameters(); }
1669 void print_returntype() { _use_separator = false; iterate_returntype(); }
1670 };
1671
1672
1673 void Method::print_name(outputStream* st) {
1674 Thread *thread = Thread::current();
1675 ResourceMark rm(thread);
1676 st->print("%s ", is_static() ? "static" : "virtual");
1677 if (WizardMode) {
1678 st->print("%s.", method_holder()->internal_name());
1679 name()->print_symbol_on(st);
1680 signature()->print_symbol_on(st);
1681 } else {
1682 SignatureTypePrinter sig(signature(), st);
1683 sig.print_returntype();
1684 st->print(" %s.", method_holder()->internal_name());
1685 name()->print_symbol_on(st);
1686 st->print("(");
1687 sig.print_parameters();
1688 st->print(")");
1689 }
1690 }
1691 #endif // !PRODUCT || INCLUDE_JVMTI
1692
1693
1694 void Method::print_codes_on(outputStream* st) const {
1695 print_codes_on(0, code_size(), st);
1696 }
1697
1698 void Method::print_codes_on(int from, int to, outputStream* st) const {
1699 Thread *thread = Thread::current();
1700 ResourceMark rm(thread);
1701 methodHandle mh (thread, (Method*)this);
1702 BytecodeStream s(mh);
1703 s.set_interval(from, to);
1704 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1705 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1706 }
1707
1708 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1709 _bci = 0;
1710 _line = 0;
1711 };
1712
1713 bool CompressedLineNumberReadStream::read_pair() {
1714 jubyte next = read_byte();
1715 // Check for terminator
1716 if (next == 0) return false;
1717 if (next == 0xFF) {
1718 // Escape character, regular compression used
1719 _bci += read_signed_int();
1720 _line += read_signed_int();
1721 } else {
1722 // Single byte compression used
1723 _bci += next >> 3;
1724 _line += next & 0x7;
1725 }
1726 return true;
1727 }
1728
1729 #if INCLUDE_JVMTI
1730
1731 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1732 BreakpointInfo* bp = method_holder()->breakpoints();
1733 for (; bp != NULL; bp = bp->next()) {
1734 if (bp->match(this, bci)) {
1735 return bp->orig_bytecode();
1736 }
1737 }
1738 {
1739 ResourceMark rm;
1740 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1741 }
1742 return Bytecodes::_shouldnotreachhere;
1743 }
1744
1745 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1746 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1747 BreakpointInfo* bp = method_holder()->breakpoints();
1748 for (; bp != NULL; bp = bp->next()) {
1749 if (bp->match(this, bci)) {
1750 bp->set_orig_bytecode(code);
1751 // and continue, in case there is more than one
1752 }
1753 }
1754 }
1755
1756 void Method::set_breakpoint(int bci) {
1757 InstanceKlass* ik = method_holder();
1758 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1759 bp->set_next(ik->breakpoints());
1760 ik->set_breakpoints(bp);
1761 // do this last:
1762 bp->set(this);
1763 }
1764
1765 static void clear_matches(Method* m, int bci) {
1766 InstanceKlass* ik = m->method_holder();
1767 BreakpointInfo* prev_bp = NULL;
1768 BreakpointInfo* next_bp;
1769 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1770 next_bp = bp->next();
1771 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1772 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1773 // do this first:
1774 bp->clear(m);
1775 // unhook it
1776 if (prev_bp != NULL)
1777 prev_bp->set_next(next_bp);
1778 else
1779 ik->set_breakpoints(next_bp);
1780 delete bp;
1781 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1782 // at same location. So we have multiple matching (method_index and bci)
1783 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1784 // breakpoint for clear_breakpoint request and keep all other method versions
1785 // BreakpointInfo for future clear_breakpoint request.
1786 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1787 // which is being called when class is unloaded. We delete all the Breakpoint
1788 // information for all versions of method. We may not correctly restore the original
1789 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1790 // so these methods won't be used anymore.
1791 if (bci >= 0) {
1792 break;
1793 }
1794 } else {
1795 // This one is a keeper.
1796 prev_bp = bp;
1797 }
1798 }
1799 }
1800
1801 void Method::clear_breakpoint(int bci) {
1802 assert(bci >= 0, "");
1803 clear_matches(this, bci);
1804 }
1805
1806 void Method::clear_all_breakpoints() {
1807 clear_matches(this, -1);
1808 }
1809
1810 #endif // INCLUDE_JVMTI
1811
1812 int Method::invocation_count() {
1813 MethodCounters *mcs = method_counters();
1814 if (TieredCompilation) {
1815 MethodData* const mdo = method_data();
1816 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1817 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1818 return InvocationCounter::count_limit;
1819 } else {
1820 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1821 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1822 }
1823 } else {
1824 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1825 }
1826 }
1827
1828 int Method::backedge_count() {
1829 MethodCounters *mcs = method_counters();
1830 if (TieredCompilation) {
1831 MethodData* const mdo = method_data();
1832 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1833 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1834 return InvocationCounter::count_limit;
1835 } else {
1836 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1837 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1838 }
1839 } else {
1840 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1841 }
1842 }
1843
1844 int Method::highest_comp_level() const {
1845 const MethodCounters* mcs = method_counters();
1846 if (mcs != NULL) {
1847 return mcs->highest_comp_level();
1848 } else {
1849 return CompLevel_none;
1850 }
1851 }
1852
1853 int Method::highest_osr_comp_level() const {
1854 const MethodCounters* mcs = method_counters();
1855 if (mcs != NULL) {
1856 return mcs->highest_osr_comp_level();
1857 } else {
1858 return CompLevel_none;
1859 }
1860 }
1861
1862 void Method::set_highest_comp_level(int level) {
1863 MethodCounters* mcs = method_counters();
1864 if (mcs != NULL) {
1865 mcs->set_highest_comp_level(level);
1866 }
1867 }
1868
1869 void Method::set_highest_osr_comp_level(int level) {
1870 MethodCounters* mcs = method_counters();
1871 if (mcs != NULL) {
1872 mcs->set_highest_osr_comp_level(level);
1873 }
1874 }
1875
1876 #if INCLUDE_JVMTI
1877
1878 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1879 _bci = bci;
1880 _name_index = m->name_index();
1881 _signature_index = m->signature_index();
1882 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1883 if (_orig_bytecode == Bytecodes::_breakpoint)
1884 _orig_bytecode = m->orig_bytecode_at(_bci);
1885 _next = NULL;
1886 }
1887
1888 void BreakpointInfo::set(Method* method) {
1889 #ifdef ASSERT
1890 {
1891 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1892 if (code == Bytecodes::_breakpoint)
1893 code = method->orig_bytecode_at(_bci);
1894 assert(orig_bytecode() == code, "original bytecode must be the same");
1895 }
1896 #endif
1897 Thread *thread = Thread::current();
1898 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1899 method->incr_number_of_breakpoints(thread);
1900 SystemDictionary::notice_modification();
1901 {
1902 // Deoptimize all dependents on this method
1903 HandleMark hm(thread);
1904 methodHandle mh(thread, method);
1905 CodeCache::flush_dependents_on_method(mh);
1906 }
1907 }
1908
1909 void BreakpointInfo::clear(Method* method) {
1910 *method->bcp_from(_bci) = orig_bytecode();
1911 assert(method->number_of_breakpoints() > 0, "must not go negative");
1912 method->decr_number_of_breakpoints(Thread::current());
1913 }
1914
1915 #endif // INCLUDE_JVMTI
1916
1917 // jmethodID handling
1918
1919 // This is a block allocating object, sort of like JNIHandleBlock, only a
1920 // lot simpler.
1921 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1922 // never get rid of it.
1923
1924 static const int min_block_size = 8;
1925
1926 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1927 friend class JNIMethodBlock;
1928 Method** _methods;
1929 int _number_of_methods;
1930 int _top;
1931 JNIMethodBlockNode* _next;
1932
1933 public:
1934
1935 JNIMethodBlockNode(int num_methods = min_block_size);
1936
1937 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1938
1939 void ensure_methods(int num_addl_methods) {
1940 if (_top < _number_of_methods) {
1941 num_addl_methods -= _number_of_methods - _top;
1942 if (num_addl_methods <= 0) {
1943 return;
1944 }
1945 }
1946 if (_next == NULL) {
1947 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1948 } else {
1949 _next->ensure_methods(num_addl_methods);
1950 }
1951 }
1952 };
1953
1954 class JNIMethodBlock : public CHeapObj<mtClass> {
1955 JNIMethodBlockNode _head;
1956 JNIMethodBlockNode *_last_free;
1957 public:
1958 static Method* const _free_method;
1959
1960 JNIMethodBlock(int initial_capacity = min_block_size)
1961 : _head(initial_capacity), _last_free(&_head) {}
1962
1963 void ensure_methods(int num_addl_methods) {
1964 _last_free->ensure_methods(num_addl_methods);
1965 }
1966
1967 Method** add_method(Method* m) {
1968 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1969 if (b->_top < b->_number_of_methods) {
1970 // top points to the next free entry.
1971 int i = b->_top;
1972 b->_methods[i] = m;
1973 b->_top++;
1974 _last_free = b;
1975 return &(b->_methods[i]);
1976 } else if (b->_top == b->_number_of_methods) {
1977 // if the next free entry ran off the block see if there's a free entry
1978 for (int i = 0; i < b->_number_of_methods; i++) {
1979 if (b->_methods[i] == _free_method) {
1980 b->_methods[i] = m;
1981 _last_free = b;
1982 return &(b->_methods[i]);
1983 }
1984 }
1985 // Only check each block once for frees. They're very unlikely.
1986 // Increment top past the end of the block.
1987 b->_top++;
1988 }
1989 // need to allocate a next block.
1990 if (b->_next == NULL) {
1991 b->_next = _last_free = new JNIMethodBlockNode();
1992 }
1993 }
1994 guarantee(false, "Should always allocate a free block");
1995 return NULL;
1996 }
1997
1998 bool contains(Method** m) {
1999 if (m == NULL) return false;
2000 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2001 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2002 // This is a bit of extra checking, for two reasons. One is
2003 // that contains() deals with pointers that are passed in by
2004 // JNI code, so making sure that the pointer is aligned
2005 // correctly is valuable. The other is that <= and > are
2006 // technically not defined on pointers, so the if guard can
2007 // pass spuriously; no modern compiler is likely to make that
2008 // a problem, though (and if one did, the guard could also
2009 // fail spuriously, which would be bad).
2010 ptrdiff_t idx = m - b->_methods;
2011 if (b->_methods + idx == m) {
2012 return true;
2013 }
2014 }
2015 }
2016 return false; // not found
2017 }
2018
2019 // Doesn't really destroy it, just marks it as free so it can be reused.
2020 void destroy_method(Method** m) {
2021 #ifdef ASSERT
2022 assert(contains(m), "should be a methodID");
2023 #endif // ASSERT
2024 *m = _free_method;
2025 }
2026
2027 // During class unloading the methods are cleared, which is different
2028 // than freed.
2029 void clear_all_methods() {
2030 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2031 for (int i = 0; i< b->_number_of_methods; i++) {
2032 b->_methods[i] = NULL;
2033 }
2034 }
2035 }
2036 #ifndef PRODUCT
2037 int count_methods() {
2038 // count all allocated methods
2039 int count = 0;
2040 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2041 for (int i = 0; i< b->_number_of_methods; i++) {
2042 if (b->_methods[i] != _free_method) count++;
2043 }
2044 }
2045 return count;
2046 }
2047 #endif // PRODUCT
2048 };
2049
2050 // Something that can't be mistaken for an address or a markOop
2051 Method* const JNIMethodBlock::_free_method = (Method*)55;
2052
2053 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2054 _number_of_methods = MAX2(num_methods, min_block_size);
2055 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2056 for (int i = 0; i < _number_of_methods; i++) {
2057 _methods[i] = JNIMethodBlock::_free_method;
2058 }
2059 }
2060
2061 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2062 ClassLoaderData* cld = loader_data;
2063 if (!SafepointSynchronize::is_at_safepoint()) {
2064 // Have to add jmethod_ids() to class loader data thread-safely.
2065 // Also have to add the method to the list safely, which the cld lock
2066 // protects as well.
2067 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2068 if (cld->jmethod_ids() == NULL) {
2069 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2070 } else {
2071 cld->jmethod_ids()->ensure_methods(capacity);
2072 }
2073 } else {
2074 // At safepoint, we are single threaded and can set this.
2075 if (cld->jmethod_ids() == NULL) {
2076 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2077 } else {
2078 cld->jmethod_ids()->ensure_methods(capacity);
2079 }
2080 }
2081 }
2082
2083 // Add a method id to the jmethod_ids
2084 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2085 ClassLoaderData* cld = loader_data;
2086
2087 if (!SafepointSynchronize::is_at_safepoint()) {
2088 // Have to add jmethod_ids() to class loader data thread-safely.
2089 // Also have to add the method to the list safely, which the cld lock
2090 // protects as well.
2091 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2092 if (cld->jmethod_ids() == NULL) {
2093 cld->set_jmethod_ids(new JNIMethodBlock());
2094 }
2095 // jmethodID is a pointer to Method*
2096 return (jmethodID)cld->jmethod_ids()->add_method(m);
2097 } else {
2098 // At safepoint, we are single threaded and can set this.
2099 if (cld->jmethod_ids() == NULL) {
2100 cld->set_jmethod_ids(new JNIMethodBlock());
2101 }
2102 // jmethodID is a pointer to Method*
2103 return (jmethodID)cld->jmethod_ids()->add_method(m);
2104 }
2105 }
2106
2107 // Mark a jmethodID as free. This is called when there is a data race in
2108 // InstanceKlass while creating the jmethodID cache.
2109 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2110 ClassLoaderData* cld = loader_data;
2111 Method** ptr = (Method**)m;
2112 assert(cld->jmethod_ids() != NULL, "should have method handles");
2113 cld->jmethod_ids()->destroy_method(ptr);
2114 }
2115
2116 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2117 // Can't assert the method_holder is the same because the new method has the
2118 // scratch method holder.
2119 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2120 == new_method->method_holder()->class_loader() ||
2121 new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2122 "changing to a different class loader");
2123 // Just change the method in place, jmethodID pointer doesn't change.
2124 *((Method**)jmid) = new_method;
2125 }
2126
2127 bool Method::is_method_id(jmethodID mid) {
2128 Method* m = resolve_jmethod_id(mid);
2129 assert(m != NULL, "should be called with non-null method");
2130 InstanceKlass* ik = m->method_holder();
2131 ClassLoaderData* cld = ik->class_loader_data();
2132 if (cld->jmethod_ids() == NULL) return false;
2133 return (cld->jmethod_ids()->contains((Method**)mid));
2134 }
2135
2136 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2137 if (mid == NULL) return NULL;
2138 Method* o = resolve_jmethod_id(mid);
2139 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2140 return NULL;
2141 }
2142 return o;
2143 };
2144
2145 void Method::set_on_stack(const bool value) {
2146 // Set both the method itself and its constant pool. The constant pool
2147 // on stack means some method referring to it is also on the stack.
2148 constants()->set_on_stack(value);
2149
2150 bool already_set = on_stack();
2151 _access_flags.set_on_stack(value);
2152 if (value && !already_set) {
2153 MetadataOnStackMark::record(this);
2154 }
2155 assert(!value || !is_old() || is_obsolete() || is_running_emcp(),
2156 "emcp methods cannot run after emcp bit is cleared");
2157 }
2158
2159 // Called when the class loader is unloaded to make all methods weak.
2160 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2161 loader_data->jmethod_ids()->clear_all_methods();
2162 }
2163
2164 bool Method::has_method_vptr(const void* ptr) {
2165 Method m;
2166 // This assumes that the vtbl pointer is the first word of a C++ object.
2167 return dereference_vptr(&m) == dereference_vptr(ptr);
2168 }
2169
2170 // Check that this pointer is valid by checking that the vtbl pointer matches
2171 bool Method::is_valid_method(const Method* m) {
2172 if (m == NULL) {
2173 return false;
2174 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2175 // Quick sanity check on pointer.
2176 return false;
2177 } else if (m->is_shared()) {
2178 return MetaspaceShared::is_valid_shared_method(m);
2179 } else if (Metaspace::contains_non_shared(m)) {
2180 return has_method_vptr((const void*)m);
2181 } else {
2182 return false;
2183 }
2184 }
2185
2186 #ifndef PRODUCT
2187 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2188 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2189 }
2190 #endif // PRODUCT
2191
2192
2193 // Printing
2194
2195 #ifndef PRODUCT
2196
2197 void Method::print_on(outputStream* st) const {
2198 ResourceMark rm;
2199 assert(is_method(), "must be method");
2200 st->print_cr("%s", internal_name());
2201 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2202 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2203 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2204 constants()->print_value_on(st); st->cr();
2205 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2206 st->print (" - name: "); name()->print_value_on(st); st->cr();
2207 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2208 st->print_cr(" - max stack: %d", max_stack());
2209 st->print_cr(" - max locals: %d", max_locals());
2210 st->print_cr(" - size of params: %d", size_of_parameters());
2211 st->print_cr(" - method size: %d", method_size());
2212 if (intrinsic_id() != vmIntrinsics::_none)
2213 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2214 if (highest_comp_level() != CompLevel_none)
2215 st->print_cr(" - highest level: %d", highest_comp_level());
2216 st->print_cr(" - vtable index: %d", _vtable_index);
2217 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2218 st->print( " - adapters: ");
2219 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2220 if (a == NULL)
2221 st->print_cr(INTPTR_FORMAT, p2i(a));
2222 else
2223 a->print_adapter_on(st);
2224 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2225 st->print_cr(" - code size: %d", code_size());
2226 if (code_size() != 0) {
2227 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2228 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2229 }
2230 if (method_data() != NULL) {
2231 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2232 }
2233 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2234 if (checked_exceptions_length() > 0) {
2235 CheckedExceptionElement* table = checked_exceptions_start();
2236 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2237 if (Verbose) {
2238 for (int i = 0; i < checked_exceptions_length(); i++) {
2239 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2240 }
2241 }
2242 }
2243 if (has_linenumber_table()) {
2244 u_char* table = compressed_linenumber_table();
2245 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2246 if (Verbose) {
2247 CompressedLineNumberReadStream stream(table);
2248 while (stream.read_pair()) {
2249 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2250 }
2251 }
2252 }
2253 st->print_cr(" - localvar length: %d", localvariable_table_length());
2254 if (localvariable_table_length() > 0) {
2255 LocalVariableTableElement* table = localvariable_table_start();
2256 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2257 if (Verbose) {
2258 for (int i = 0; i < localvariable_table_length(); i++) {
2259 int bci = table[i].start_bci;
2260 int len = table[i].length;
2261 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2262 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2263 int slot = table[i].slot;
2264 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2265 }
2266 }
2267 }
2268 if (code() != NULL) {
2269 st->print (" - compiled code: ");
2270 code()->print_value_on(st);
2271 }
2272 if (is_native()) {
2273 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2274 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2275 }
2276 }
2277
2278 void Method::print_linkage_flags(outputStream* st) {
2279 access_flags().print_on(st);
2280 if (is_default_method()) {
2281 st->print("default ");
2282 }
2283 if (is_overpass()) {
2284 st->print("overpass ");
2285 }
2286 }
2287 #endif //PRODUCT
2288
2289 void Method::print_value_on(outputStream* st) const {
2290 assert(is_method(), "must be method");
2291 st->print("%s", internal_name());
2292 print_address_on(st);
2293 st->print(" ");
2294 name()->print_value_on(st);
2295 st->print(" ");
2296 signature()->print_value_on(st);
2297 st->print(" in ");
2298 method_holder()->print_value_on(st);
2299 if (WizardMode) st->print("#%d", _vtable_index);
2300 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2301 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2302 }
2303
2304 #if INCLUDE_SERVICES
2305 // Size Statistics
2306 void Method::collect_statistics(KlassSizeStats *sz) const {
2307 int mysize = sz->count(this);
2308 sz->_method_bytes += mysize;
2309 sz->_method_all_bytes += mysize;
2310 sz->_rw_bytes += mysize;
2311
2312 if (constMethod()) {
2313 constMethod()->collect_statistics(sz);
2314 }
2315 if (method_data()) {
2316 method_data()->collect_statistics(sz);
2317 }
2318 }
2319 #endif // INCLUDE_SERVICES
2320
2321 // LogTouchedMethods and PrintTouchedMethods
2322
2323 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2324 // the Method may be garbage collected. Let's roll our own hash table.
2325 class TouchedMethodRecord : CHeapObj<mtTracing> {
2326 public:
2327 // It's OK to store Symbols here because they will NOT be GC'ed if
2328 // LogTouchedMethods is enabled.
2329 TouchedMethodRecord* _next;
2330 Symbol* _class_name;
2331 Symbol* _method_name;
2332 Symbol* _method_signature;
2333 };
2334
2335 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2336 static TouchedMethodRecord** _touched_method_table = NULL;
2337
2338 void Method::log_touched(TRAPS) {
2339
2340 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2341 Symbol* my_class = klass_name();
2342 Symbol* my_name = name();
2343 Symbol* my_sig = signature();
2344
2345 unsigned int hash = my_class->identity_hash() +
2346 my_name->identity_hash() +
2347 my_sig->identity_hash();
2348 juint index = juint(hash) % table_size;
2349
2350 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2351 if (_touched_method_table == NULL) {
2352 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2353 mtTracing, CURRENT_PC);
2354 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2355 }
2356
2357 TouchedMethodRecord* ptr = _touched_method_table[index];
2358 while (ptr) {
2359 if (ptr->_class_name == my_class &&
2360 ptr->_method_name == my_name &&
2361 ptr->_method_signature == my_sig) {
2362 return;
2363 }
2364 if (ptr->_next == NULL) break;
2365 ptr = ptr->_next;
2366 }
2367 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2368 my_class->increment_refcount();
2369 my_name->increment_refcount();
2370 my_sig->increment_refcount();
2371 nptr->_class_name = my_class;
2372 nptr->_method_name = my_name;
2373 nptr->_method_signature = my_sig;
2374 nptr->_next = NULL;
2375
2376 if (ptr == NULL) {
2377 // first
2378 _touched_method_table[index] = nptr;
2379 } else {
2380 ptr->_next = nptr;
2381 }
2382 }
2383
2384 void Method::print_touched_methods(outputStream* out) {
2385 MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2386 out->print_cr("# Method::print_touched_methods version 1");
2387 if (_touched_method_table) {
2388 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2389 TouchedMethodRecord* ptr = _touched_method_table[i];
2390 while(ptr) {
2391 ptr->_class_name->print_symbol_on(out); out->print(".");
2392 ptr->_method_name->print_symbol_on(out); out->print(":");
2393 ptr->_method_signature->print_symbol_on(out); out->cr();
2394 ptr = ptr->_next;
2395 }
2396 }
2397 }
2398 }
2399
2400 // Verification
2401
2402 void Method::verify_on(outputStream* st) {
2403 guarantee(is_method(), "object must be method");
2404 guarantee(constants()->is_constantPool(), "should be constant pool");
2405 MethodData* md = method_data();
2406 guarantee(md == NULL ||
2407 md->is_methodData(), "should be method data");
2408 }