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