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