1 /*
2 * Copyright (c) 1997, 2018, 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/metadataOnStackMark.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "code/codeCache.hpp"
29 #include "code/debugInfoRec.hpp"
30 #include "gc/shared/collectedHeap.inline.hpp"
31 #include "gc/shared/gcLocker.hpp"
32 #include "gc/shared/generation.hpp"
33 #include "interpreter/bytecodeStream.hpp"
34 #include "interpreter/bytecodeTracer.hpp"
35 #include "interpreter/bytecodes.hpp"
36 #include "interpreter/interpreter.hpp"
37 #include "interpreter/oopMapCache.hpp"
38 #include "memory/allocation.inline.hpp"
39 #include "memory/heapInspection.hpp"
40 #include "memory/metadataFactory.hpp"
41 #include "memory/metaspaceClosure.hpp"
42 #include "memory/metaspaceShared.hpp"
43 #include "memory/oopFactory.hpp"
44 #include "memory/resourceArea.hpp"
45 #include "oops/constMethod.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.inline.hpp"
60 #include "runtime/relocator.hpp"
61 #include "runtime/sharedRuntime.hpp"
62 #include "runtime/signature.hpp"
63 #include "utilities/align.hpp"
64 #include "utilities/quickSort.hpp"
65 #include "utilities/vmError.hpp"
66 #include "utilities/xmlstream.hpp"
67
68 // Implementation of Method
69
70 Method* Method::allocate(ClassLoaderData* loader_data,
71 int byte_code_size,
72 AccessFlags access_flags,
73 InlineTableSizes* sizes,
74 ConstMethod::MethodType method_type,
75 TRAPS) {
76 assert(!access_flags.is_native() || byte_code_size == 0,
77 "native methods should not contain byte codes");
78 ConstMethod* cm = ConstMethod::allocate(loader_data,
79 byte_code_size,
80 sizes,
81 method_type,
82 CHECK_NULL);
83 int size = Method::size(access_flags.is_native());
84 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
85 }
86
87 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
88 NoSafepointVerifier no_safepoint;
89 set_constMethod(xconst);
90 set_access_flags(access_flags);
91 set_intrinsic_id(vmIntrinsics::_none);
92 set_force_inline(false);
93 set_hidden(false);
94 set_dont_inline(false);
95 set_has_injected_profile(false);
96 set_method_data(NULL);
97 clear_method_counters();
98 set_vtable_index(Method::garbage_vtable_index);
99
100 // Fix and bury in Method*
101 set_interpreter_entry(NULL); // sets i2i entry and from_int
102 set_adapter_entry(NULL);
103 clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i
104
105 if (access_flags.is_native()) {
106 clear_native_function();
107 set_signature_handler(NULL);
108 }
109
110 NOT_PRODUCT(set_compiled_invocation_count(0);)
111 }
112
113 // Release Method*. The nmethod will be gone when we get here because
114 // we've walked the code cache.
115 void Method::deallocate_contents(ClassLoaderData* loader_data) {
116 MetadataFactory::free_metadata(loader_data, constMethod());
117 set_constMethod(NULL);
118 MetadataFactory::free_metadata(loader_data, method_data());
119 set_method_data(NULL);
120 MetadataFactory::free_metadata(loader_data, method_counters());
121 clear_method_counters();
122 // The nmethod will be gone when we get here.
123 if (code() != NULL) _code = NULL;
124 }
125
126 address Method::get_i2c_entry() {
127 assert(adapter() != NULL, "must have");
128 return adapter()->get_i2c_entry();
129 }
130
131 address Method::get_c2i_entry() {
132 assert(adapter() != NULL, "must have");
133 return adapter()->get_c2i_entry();
134 }
135
136 address Method::get_c2i_unverified_entry() {
137 assert(adapter() != NULL, "must have");
138 return adapter()->get_c2i_unverified_entry();
139 }
140
141 char* Method::name_and_sig_as_C_string() const {
142 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
143 }
144
145 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
146 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
147 }
148
149 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
150 const char* klass_name = klass->external_name();
151 int klass_name_len = (int)strlen(klass_name);
152 int method_name_len = method_name->utf8_length();
153 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
154 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
155 strcpy(dest, klass_name);
156 dest[klass_name_len] = '.';
157 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
158 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
159 dest[len] = 0;
160 return dest;
161 }
162
163 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
164 Symbol* klass_name = klass->name();
165 klass_name->as_klass_external_name(buf, size);
166 int len = (int)strlen(buf);
167
168 if (len < size - 1) {
169 buf[len++] = '.';
170
171 method_name->as_C_string(&(buf[len]), size - len);
172 len = (int)strlen(buf);
173
174 signature->as_C_string(&(buf[len]), size - len);
175 }
176
177 return buf;
178 }
179
180 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
181 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
182 // access exception table
183 ExceptionTable table(mh());
184 int length = table.length();
185 // iterate through all entries sequentially
186 constantPoolHandle pool(THREAD, mh->constants());
187 for (int i = 0; i < length; i ++) {
188 //reacquire the table in case a GC happened
189 ExceptionTable table(mh());
190 int beg_bci = table.start_pc(i);
191 int end_bci = table.end_pc(i);
192 assert(beg_bci <= end_bci, "inconsistent exception table");
193 if (beg_bci <= throw_bci && throw_bci < end_bci) {
194 // exception handler bci range covers throw_bci => investigate further
195 int handler_bci = table.handler_pc(i);
196 int klass_index = table.catch_type_index(i);
197 if (klass_index == 0) {
198 return handler_bci;
199 } else if (ex_klass == NULL) {
200 return handler_bci;
201 } else {
202 // we know the exception class => get the constraint class
203 // this may require loading of the constraint class; if verification
204 // fails or some other exception occurs, return handler_bci
205 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
206 assert(k != NULL, "klass not loaded");
207 if (ex_klass->is_subtype_of(k)) {
208 return handler_bci;
209 }
210 }
211 }
212 }
213
214 return -1;
215 }
216
217 void Method::mask_for(int bci, InterpreterOopMap* mask) {
218 methodHandle h_this(Thread::current(), this);
219 // Only GC uses the OopMapCache during thread stack root scanning
220 // any other uses generate an oopmap but do not save it in the cache.
221 if (Universe::heap()->is_gc_active()) {
222 method_holder()->mask_for(h_this, bci, mask);
223 } else {
224 OopMapCache::compute_one_oop_map(h_this, bci, mask);
225 }
226 return;
227 }
228
229
230 int Method::bci_from(address bcp) const {
231 if (is_native() && bcp == 0) {
232 return 0;
233 }
234 #ifdef ASSERT
235 {
236 ResourceMark rm;
237 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
238 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
239 p2i(bcp), name_and_sig_as_C_string());
240 }
241 #endif
242 return bcp - code_base();
243 }
244
245
246 int Method::validate_bci(int bci) const {
247 return (bci == 0 || bci < code_size()) ? bci : -1;
248 }
249
250 // Return bci if it appears to be a valid bcp
251 // Return -1 otherwise.
252 // Used by profiling code, when invalid data is a possibility.
253 // The caller is responsible for validating the Method* itself.
254 int Method::validate_bci_from_bcp(address bcp) const {
255 // keep bci as -1 if not a valid bci
256 int bci = -1;
257 if (bcp == 0 || bcp == code_base()) {
258 // code_size() may return 0 and we allow 0 here
259 // the method may be native
260 bci = 0;
261 } else if (contains(bcp)) {
262 bci = bcp - code_base();
263 }
264 // Assert that if we have dodged any asserts, bci is negative.
265 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
266 return bci;
267 }
268
269 address Method::bcp_from(int bci) const {
270 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
271 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
272 address bcp = code_base() + bci;
273 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
274 return bcp;
275 }
276
277 address Method::bcp_from(address bcp) const {
278 if (is_native() && bcp == NULL) {
279 return code_base();
280 } else {
281 return bcp;
282 }
283 }
284
285 int Method::size(bool is_native) {
286 // If native, then include pointers for native_function and signature_handler
287 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
288 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
289 return align_metadata_size(header_size() + extra_words);
290 }
291
292
293 Symbol* Method::klass_name() const {
294 return method_holder()->name();
295 }
296
297
298 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
299 log_trace(cds)("Iter(Method): %p", this);
300
301 it->push(&_constMethod);
302 it->push(&_method_data);
303 it->push(&_method_counters);
304 }
305
306 // Attempt to return method oop to original state. Clear any pointers
307 // (to objects outside the shared spaces). We won't be able to predict
308 // where they should point in a new JVM. Further initialize some
309 // entries now in order allow them to be write protected later.
310
311 void Method::remove_unshareable_info() {
312 unlink_method();
313 }
314
315 void Method::set_vtable_index(int index) {
316 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
317 // At runtime initialize_vtable is rerun as part of link_class_impl()
318 // for a shared class loaded by the non-boot loader to obtain the loader
319 // constraints based on the runtime classloaders' context.
320 return; // don't write into the shared class
321 } else {
322 _vtable_index = index;
323 }
324 }
325
326 void Method::set_itable_index(int index) {
327 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
328 // At runtime initialize_itable is rerun as part of link_class_impl()
329 // for a shared class loaded by the non-boot loader to obtain the loader
330 // constraints based on the runtime classloaders' context. The dumptime
331 // itable index should be the same as the runtime index.
332 assert(_vtable_index == itable_index_max - index,
333 "archived itable index is different from runtime index");
334 return; // don’t write into the shared class
335 } else {
336 _vtable_index = itable_index_max - index;
337 }
338 assert(valid_itable_index(), "");
339 }
340
341
342
343 bool Method::was_executed_more_than(int n) {
344 // Invocation counter is reset when the Method* is compiled.
345 // If the method has compiled code we therefore assume it has
346 // be excuted more than n times.
347 if (is_accessor() || is_empty_method() || (code() != NULL)) {
348 // interpreter doesn't bump invocation counter of trivial methods
349 // compiler does not bump invocation counter of compiled methods
350 return true;
351 }
352 else if ((method_counters() != NULL &&
353 method_counters()->invocation_counter()->carry()) ||
354 (method_data() != NULL &&
355 method_data()->invocation_counter()->carry())) {
356 // The carry bit is set when the counter overflows and causes
357 // a compilation to occur. We don't know how many times
358 // the counter has been reset, so we simply assume it has
359 // been executed more than n times.
360 return true;
361 } else {
362 return invocation_count() > n;
363 }
364 }
365
366 void Method::print_invocation_count() {
367 if (is_static()) tty->print("static ");
368 if (is_final()) tty->print("final ");
369 if (is_synchronized()) tty->print("synchronized ");
370 if (is_native()) tty->print("native ");
371 tty->print("%s::", method_holder()->external_name());
372 name()->print_symbol_on(tty);
373 signature()->print_symbol_on(tty);
374
375 if (WizardMode) {
376 // dump the size of the byte codes
377 tty->print(" {%d}", code_size());
378 }
379 tty->cr();
380
381 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count());
382 tty->print_cr (" invocation_counter: %8d ", invocation_count());
383 tty->print_cr (" backedge_counter: %8d ", backedge_count());
384 #ifndef PRODUCT
385 if (CountCompiledCalls) {
386 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count());
387 }
388 #endif
389 }
390
391 // Build a MethodData* object to hold information about this method
392 // collected in the interpreter.
393 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
394 // Do not profile the method if metaspace has hit an OOM previously
395 // allocating profiling data. Callers clear pending exception so don't
396 // add one here.
397 if (ClassLoaderDataGraph::has_metaspace_oom()) {
398 return;
399 }
400
401 // Grab a lock here to prevent multiple
402 // MethodData*s from being created.
403 MutexLocker ml(MethodData_lock, THREAD);
404 if (method->method_data() == NULL) {
405 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
406 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
407 if (HAS_PENDING_EXCEPTION) {
408 CompileBroker::log_metaspace_failure();
409 ClassLoaderDataGraph::set_metaspace_oom(true);
410 return; // return the exception (which is cleared)
411 }
412
413 method->set_method_data(method_data);
414 if (PrintMethodData && (Verbose || WizardMode)) {
415 ResourceMark rm(THREAD);
416 tty->print("build_interpreter_method_data for ");
417 method->print_name(tty);
418 tty->cr();
419 // At the end of the run, the MDO, full of data, will be dumped.
420 }
421 }
422 }
423
424 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
425 // Do not profile the method if metaspace has hit an OOM previously
426 if (ClassLoaderDataGraph::has_metaspace_oom()) {
427 return NULL;
428 }
429
430 methodHandle mh(m);
431 MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
432 if (HAS_PENDING_EXCEPTION) {
433 CompileBroker::log_metaspace_failure();
434 ClassLoaderDataGraph::set_metaspace_oom(true);
435 return NULL; // return the exception (which is cleared)
436 }
437 if (!mh->init_method_counters(counters)) {
438 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
439 }
440
441 if (LogTouchedMethods) {
442 mh->log_touched(CHECK_NULL);
443 }
444
445 return mh->method_counters();
446 }
447
448 bool Method::init_method_counters(MethodCounters* counters) {
449 // Try to install a pointer to MethodCounters, return true on success.
450 return Atomic::replace_if_null(counters, &_method_counters);
451 }
452
453 void Method::cleanup_inline_caches() {
454 // The current system doesn't use inline caches in the interpreter
455 // => nothing to do (keep this method around for future use)
456 }
457
458
459 int Method::extra_stack_words() {
460 // not an inline function, to avoid a header dependency on Interpreter
461 return extra_stack_entries() * Interpreter::stackElementSize;
462 }
463
464
465 void Method::compute_size_of_parameters(Thread *thread) {
466 ArgumentSizeComputer asc(signature());
467 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
468 }
469
470 BasicType Method::result_type() const {
471 ResultTypeFinder rtf(signature());
472 return rtf.type();
473 }
474
475
476 bool Method::is_empty_method() const {
477 return code_size() == 1
478 && *code_base() == Bytecodes::_return;
479 }
480
481
482 bool Method::is_vanilla_constructor() const {
483 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
484 // which only calls the superclass vanilla constructor and possibly does stores of
485 // zero constants to local fields:
486 //
487 // aload_0
488 // invokespecial
489 // indexbyte1
490 // indexbyte2
491 //
492 // followed by an (optional) sequence of:
493 //
494 // aload_0
495 // aconst_null / iconst_0 / fconst_0 / dconst_0
496 // putfield
497 // indexbyte1
498 // indexbyte2
499 //
500 // followed by:
501 //
502 // return
503
504 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
505 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
506 int size = code_size();
507 // Check if size match
508 if (size == 0 || size % 5 != 0) return false;
509 address cb = code_base();
510 int last = size - 1;
511 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
512 // Does not call superclass default constructor
513 return false;
514 }
515 // Check optional sequence
516 for (int i = 4; i < last; i += 5) {
517 if (cb[i] != Bytecodes::_aload_0) return false;
518 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
519 if (cb[i+2] != Bytecodes::_putfield) return false;
520 }
521 return true;
522 }
523
524
525 bool Method::compute_has_loops_flag() {
526 BytecodeStream bcs(this);
527 Bytecodes::Code bc;
528
529 while ((bc = bcs.next()) >= 0) {
530 switch( bc ) {
531 case Bytecodes::_ifeq:
532 case Bytecodes::_ifnull:
533 case Bytecodes::_iflt:
534 case Bytecodes::_ifle:
535 case Bytecodes::_ifne:
536 case Bytecodes::_ifnonnull:
537 case Bytecodes::_ifgt:
538 case Bytecodes::_ifge:
539 case Bytecodes::_if_icmpeq:
540 case Bytecodes::_if_icmpne:
541 case Bytecodes::_if_icmplt:
542 case Bytecodes::_if_icmpgt:
543 case Bytecodes::_if_icmple:
544 case Bytecodes::_if_icmpge:
545 case Bytecodes::_if_acmpeq:
546 case Bytecodes::_if_acmpne:
547 case Bytecodes::_goto:
548 case Bytecodes::_jsr:
549 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
550 break;
551
552 case Bytecodes::_goto_w:
553 case Bytecodes::_jsr_w:
554 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
555 break;
556
557 default:
558 break;
559 }
560 }
561 _access_flags.set_loops_flag_init();
562 return _access_flags.has_loops();
563 }
564
565 bool Method::is_final_method(AccessFlags class_access_flags) const {
566 // or "does_not_require_vtable_entry"
567 // default method or overpass can occur, is not final (reuses vtable entry)
568 // private methods in classes get vtable entries for backward class compatibility.
569 if (is_overpass() || is_default_method()) return false;
570 return is_final() || class_access_flags.is_final();
571 }
572
573 bool Method::is_final_method() const {
574 return is_final_method(method_holder()->access_flags());
575 }
576
577 bool Method::is_default_method() const {
578 if (method_holder() != NULL &&
579 method_holder()->is_interface() &&
580 !is_abstract() && !is_private()) {
581 return true;
582 } else {
583 return false;
584 }
585 }
586
587 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
588 if (is_final_method(class_access_flags)) return true;
589 #ifdef ASSERT
590 ResourceMark rm;
591 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
592 if (class_access_flags.is_interface()) {
593 assert(is_nonv == is_static() || is_nonv == is_private(),
594 "nonvirtual unexpected for non-static, non-private: %s",
595 name_and_sig_as_C_string());
596 }
597 #endif
598 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
599 return vtable_index() == nonvirtual_vtable_index;
600 }
601
602 bool Method::can_be_statically_bound() const {
603 return can_be_statically_bound(method_holder()->access_flags());
604 }
605
606 bool Method::is_accessor() const {
607 return is_getter() || is_setter();
608 }
609
610 bool Method::is_getter() const {
611 if (code_size() != 5) return false;
612 if (size_of_parameters() != 1) return false;
613 if (java_code_at(0) != Bytecodes::_aload_0) return false;
614 if (java_code_at(1) != Bytecodes::_getfield) return false;
615 switch (java_code_at(4)) {
616 case Bytecodes::_ireturn:
617 case Bytecodes::_lreturn:
618 case Bytecodes::_freturn:
619 case Bytecodes::_dreturn:
620 case Bytecodes::_areturn:
621 break;
622 default:
623 return false;
624 }
625 return true;
626 }
627
628 bool Method::is_setter() const {
629 if (code_size() != 6) return false;
630 if (java_code_at(0) != Bytecodes::_aload_0) return false;
631 switch (java_code_at(1)) {
632 case Bytecodes::_iload_1:
633 case Bytecodes::_aload_1:
634 case Bytecodes::_fload_1:
635 if (size_of_parameters() != 2) return false;
636 break;
637 case Bytecodes::_dload_1:
638 case Bytecodes::_lload_1:
639 if (size_of_parameters() != 3) return false;
640 break;
641 default:
642 return false;
643 }
644 if (java_code_at(2) != Bytecodes::_putfield) return false;
645 if (java_code_at(5) != Bytecodes::_return) return false;
646 return true;
647 }
648
649 bool Method::is_constant_getter() const {
650 int last_index = code_size() - 1;
651 // Check if the first 1-3 bytecodes are a constant push
652 // and the last bytecode is a return.
653 return (2 <= code_size() && code_size() <= 4 &&
654 Bytecodes::is_const(java_code_at(0)) &&
655 Bytecodes::length_for(java_code_at(0)) == last_index &&
656 Bytecodes::is_return(java_code_at(last_index)));
657 }
658
659 bool Method::is_initializer() const {
660 return is_object_initializer() || is_static_initializer();
661 }
662
663 bool Method::has_valid_initializer_flags() const {
664 return (is_static() ||
665 method_holder()->major_version() < 51);
666 }
667
668 bool Method::is_static_initializer() const {
669 // For classfiles version 51 or greater, ensure that the clinit method is
670 // static. Non-static methods with the name "<clinit>" are not static
671 // initializers. (older classfiles exempted for backward compatibility)
672 return name() == vmSymbols::class_initializer_name() &&
673 has_valid_initializer_flags();
674 }
675
676 bool Method::is_object_initializer() const {
677 return name() == vmSymbols::object_initializer_name();
678 }
679
680 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
681 int length = method->checked_exceptions_length();
682 if (length == 0) { // common case
683 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
684 } else {
685 methodHandle h_this(THREAD, method);
686 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
687 objArrayHandle mirrors (THREAD, m_oop);
688 for (int i = 0; i < length; i++) {
689 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
690 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
691 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
692 mirrors->obj_at_put(i, k->java_mirror());
693 }
694 return mirrors;
695 }
696 };
697
698
699 int Method::line_number_from_bci(int bci) const {
700 if (bci == SynchronizationEntryBCI) bci = 0;
701 assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
702 int best_bci = 0;
703 int best_line = -1;
704
705 if (has_linenumber_table()) {
706 // The line numbers are a short array of 2-tuples [start_pc, line_number].
707 // Not necessarily sorted and not necessarily one-to-one.
708 CompressedLineNumberReadStream stream(compressed_linenumber_table());
709 while (stream.read_pair()) {
710 if (stream.bci() == bci) {
711 // perfect match
712 return stream.line();
713 } else {
714 // update best_bci/line
715 if (stream.bci() < bci && stream.bci() >= best_bci) {
716 best_bci = stream.bci();
717 best_line = stream.line();
718 }
719 }
720 }
721 }
722 return best_line;
723 }
724
725
726 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
727 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
728 Thread *thread = Thread::current();
729 Symbol* klass_name = constants()->klass_name_at(klass_index);
730 Handle loader(thread, method_holder()->class_loader());
731 Handle prot (thread, method_holder()->protection_domain());
732 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
733 } else {
734 return true;
735 }
736 }
737
738
739 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
740 int klass_index = constants()->klass_ref_index_at(refinfo_index);
741 if (must_be_resolved) {
742 // Make sure klass is resolved in constantpool.
743 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
744 }
745 return is_klass_loaded_by_klass_index(klass_index);
746 }
747
748
749 void Method::set_native_function(address function, bool post_event_flag) {
750 assert(function != NULL, "use clear_native_function to unregister natives");
751 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
752 address* native_function = native_function_addr();
753
754 // We can see racers trying to place the same native function into place. Once
755 // is plenty.
756 address current = *native_function;
757 if (current == function) return;
758 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
759 function != NULL) {
760 // native_method_throw_unsatisfied_link_error_entry() should only
761 // be passed when post_event_flag is false.
762 assert(function !=
763 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
764 "post_event_flag mis-match");
765
766 // post the bind event, and possible change the bind function
767 JvmtiExport::post_native_method_bind(this, &function);
768 }
769 *native_function = function;
770 // This function can be called more than once. We must make sure that we always
771 // use the latest registered method -> check if a stub already has been generated.
772 // If so, we have to make it not_entrant.
773 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
774 if (nm != NULL) {
775 nm->make_not_entrant();
776 }
777 }
778
779
780 bool Method::has_native_function() const {
781 if (is_method_handle_intrinsic())
782 return false; // special-cased in SharedRuntime::generate_native_wrapper
783 address func = native_function();
784 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
785 }
786
787
788 void Method::clear_native_function() {
789 // Note: is_method_handle_intrinsic() is allowed here.
790 set_native_function(
791 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
792 !native_bind_event_is_interesting);
793 clear_code();
794 }
795
796 address Method::critical_native_function() {
797 methodHandle mh(this);
798 return NativeLookup::lookup_critical_entry(mh);
799 }
800
801
802 void Method::set_signature_handler(address handler) {
803 address* signature_handler = signature_handler_addr();
804 *signature_handler = handler;
805 }
806
807
808 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
809 if (PrintCompilation && report) {
810 ttyLocker ttyl;
811 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
812 if (comp_level == CompLevel_all) {
813 tty->print("all levels ");
814 } else {
815 tty->print("levels ");
816 for (int i = (int)CompLevel_none; i <= comp_level; i++) {
817 tty->print("%d ", i);
818 }
819 }
820 this->print_short_name(tty);
821 int size = this->code_size();
822 if (size > 0) {
823 tty->print(" (%d bytes)", size);
824 }
825 if (reason != NULL) {
826 tty->print(" %s", reason);
827 }
828 tty->cr();
829 }
830 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
831 ttyLocker ttyl;
832 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
833 os::current_thread_id(), is_osr, comp_level);
834 if (reason != NULL) {
835 xtty->print(" reason=\'%s\'", reason);
836 }
837 xtty->method(this);
838 xtty->stamp();
839 xtty->end_elem();
840 }
841 }
842
843 bool Method::is_always_compilable() const {
844 // Generated adapters must be compiled
845 if (is_method_handle_intrinsic() && is_synthetic()) {
846 assert(!is_not_c1_compilable(), "sanity check");
847 assert(!is_not_c2_compilable(), "sanity check");
848 return true;
849 }
850
851 return false;
852 }
853
854 bool Method::is_not_compilable(int comp_level) const {
855 if (number_of_breakpoints() > 0)
856 return true;
857 if (is_always_compilable())
858 return false;
859 if (comp_level == CompLevel_any)
860 return is_not_c1_compilable() || is_not_c2_compilable();
861 if (is_c1_compile(comp_level))
862 return is_not_c1_compilable();
863 if (is_c2_compile(comp_level))
864 return is_not_c2_compilable();
865 return false;
866 }
867
868 // call this when compiler finds that this method is not compilable
869 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
870 if (is_always_compilable()) {
871 // Don't mark a method which should be always compilable
872 return;
873 }
874 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
875 if (comp_level == CompLevel_all) {
876 set_not_c1_compilable();
877 set_not_c2_compilable();
878 } else {
879 if (is_c1_compile(comp_level))
880 set_not_c1_compilable();
881 if (is_c2_compile(comp_level))
882 set_not_c2_compilable();
883 }
884 CompilationPolicy::policy()->disable_compilation(this);
885 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
886 }
887
888 bool Method::is_not_osr_compilable(int comp_level) const {
889 if (is_not_compilable(comp_level))
890 return true;
891 if (comp_level == CompLevel_any)
892 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
893 if (is_c1_compile(comp_level))
894 return is_not_c1_osr_compilable();
895 if (is_c2_compile(comp_level))
896 return is_not_c2_osr_compilable();
897 return false;
898 }
899
900 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
901 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
902 if (comp_level == CompLevel_all) {
903 set_not_c1_osr_compilable();
904 set_not_c2_osr_compilable();
905 } else {
906 if (is_c1_compile(comp_level))
907 set_not_c1_osr_compilable();
908 if (is_c2_compile(comp_level))
909 set_not_c2_osr_compilable();
910 }
911 CompilationPolicy::policy()->disable_compilation(this);
912 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
913 }
914
915 // Revert to using the interpreter and clear out the nmethod
916 void Method::clear_code(bool acquire_lock /* = true */) {
917 MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
918 // this may be NULL if c2i adapters have not been made yet
919 // Only should happen at allocate time.
920 if (adapter() == NULL) {
921 _from_compiled_entry = NULL;
922 } else {
923 _from_compiled_entry = adapter()->get_c2i_entry();
924 }
925 OrderAccess::storestore();
926 _from_interpreted_entry = _i2i_entry;
927 OrderAccess::storestore();
928 _code = NULL;
929 }
930
931 #if INCLUDE_CDS
932 // Called by class data sharing to remove any entry points (which are not shared)
933 void Method::unlink_method() {
934 _code = NULL;
935
936 assert(DumpSharedSpaces, "dump time only");
937 // Set the values to what they should be at run time. Note that
938 // this Method can no longer be executed during dump time.
939 _i2i_entry = Interpreter::entry_for_cds_method(this);
940 _from_interpreted_entry = _i2i_entry;
941
942 if (is_native()) {
943 *native_function_addr() = NULL;
944 set_signature_handler(NULL);
945 }
946 NOT_PRODUCT(set_compiled_invocation_count(0);)
947
948 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
949 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
950 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
951 assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
952
953 set_method_data(NULL);
954 clear_method_counters();
955 }
956 #endif
957
958 /****************************************************************************
959 // The following illustrates how the entries work for CDS shared Methods:
960 //
961 // Our goal is to delay writing into a shared Method until it's compiled.
962 // Hence, we want to determine the initial values for _i2i_entry,
963 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
964 //
965 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
966 // They also have similar signatures so that they will share the same
967 // AdapterHandlerEntry.
968 //
969 // _adapter_trampoline points to a fixed location in the RW section of
970 // the CDS archive. This location initially contains a NULL pointer. When the
971 // first of method A or B is linked, an AdapterHandlerEntry is allocated
972 // dynamically, and its c2i/i2c entries are generated.
973 //
974 // _i2i_entry and _from_interpreted_entry initially points to the same
975 // (fixed) location in the CODE section of the CDS archive. This contains
976 // an unconditional branch to the actual entry for "zero_locals", which is
977 // generated at run time and may be on an arbitrary address. Thus, the
978 // unconditional branch is also generated at run time to jump to the correct
979 // address.
980 //
981 // Similarly, _from_compiled_entry points to a fixed address in the CODE
982 // section. This address has enough space for an unconditional branch
983 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
984 // initialized, and the address for the actual c2i_entry is known, we emit a
985 // branch instruction here to branch to the actual c2i_entry.
986 //
987 // The effect of the extra branch on the i2i and c2i entries is negligible.
988 //
989 // The reason for putting _adapter_trampoline in RO is many shared Methods
990 // share the same AdapterHandlerEntry, so we can save space in the RW section
991 // by having the extra indirection.
992
993
994 [Method A: RW]
995 _constMethod ----> [ConstMethod: RO]
996 _adapter_trampoline -----------+
997 |
998 _i2i_entry (same value as method B) |
999 _from_interpreted_entry (same value as method B) |
1000 _from_compiled_entry (same value as method B) |
1001 |
1002 |
1003 [Method B: RW] +--------+
1004 _constMethod ----> [ConstMethod: RO] |
1005 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1006 |
1007 +-------------------------------+
1008 |
1009 +----> [AdapterHandlerEntry] (allocated at run time)
1010 _fingerprint
1011 _c2i_entry ---------------------------------+->[c2i entry..]
1012 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1013 _from_interpreted_entry | _c2i_unverified_entry | |
1014 | | | |
1015 | | (_cds_entry_table: CODE) | |
1016 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1017 | | (allocated at run time) | |
1018 | | ... [asm code ...] | |
1019 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1020 | | |
1021 | | |
1022 +-[compiled]-------------------------------------------------------------------+ |
1023 |
1024 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1025 [jmp c2i_entry] ------------------------------------------------------+
1026
1027 ***/
1028
1029 // Called when the method_holder is getting linked. Setup entrypoints so the method
1030 // is ready to be called from interpreter, compiler, and vtables.
1031 void Method::link_method(const methodHandle& h_method, TRAPS) {
1032 // If the code cache is full, we may reenter this function for the
1033 // leftover methods that weren't linked.
1034 if (is_shared()) {
1035 address entry = Interpreter::entry_for_cds_method(h_method);
1036 assert(entry != NULL && entry == _i2i_entry,
1037 "should be correctly set during dump time");
1038 if (adapter() != NULL) {
1039 return;
1040 }
1041 assert(entry == _from_interpreted_entry,
1042 "should be correctly set during dump time");
1043 } else if (_i2i_entry != NULL) {
1044 return;
1045 }
1046 assert( _code == NULL, "nothing compiled yet" );
1047
1048 // Setup interpreter entrypoint
1049 assert(this == h_method(), "wrong h_method()" );
1050
1051 if (!is_shared()) {
1052 assert(adapter() == NULL, "init'd to NULL");
1053 address entry = Interpreter::entry_for_method(h_method);
1054 assert(entry != NULL, "interpreter entry must be non-null");
1055 // Sets both _i2i_entry and _from_interpreted_entry
1056 set_interpreter_entry(entry);
1057 }
1058
1059 // Don't overwrite already registered native entries.
1060 if (is_native() && !has_native_function()) {
1061 set_native_function(
1062 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1063 !native_bind_event_is_interesting);
1064 }
1065
1066 // Setup compiler entrypoint. This is made eagerly, so we do not need
1067 // special handling of vtables. An alternative is to make adapters more
1068 // lazily by calling make_adapter() from from_compiled_entry() for the
1069 // normal calls. For vtable calls life gets more complicated. When a
1070 // call-site goes mega-morphic we need adapters in all methods which can be
1071 // called from the vtable. We need adapters on such methods that get loaded
1072 // later. Ditto for mega-morphic itable calls. If this proves to be a
1073 // problem we'll make these lazily later.
1074 (void) make_adapters(h_method, CHECK);
1075
1076 // ONLY USE the h_method now as make_adapter may have blocked
1077
1078 }
1079
1080 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1081 // Adapters for compiled code are made eagerly here. They are fairly
1082 // small (generally < 100 bytes) and quick to make (and cached and shared)
1083 // so making them eagerly shouldn't be too expensive.
1084 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1085 if (adapter == NULL ) {
1086 if (!is_init_completed()) {
1087 // Don't throw exceptions during VM initialization because java.lang.* classes
1088 // might not have been initialized, causing problems when constructing the
1089 // Java exception object.
1090 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1091 } else {
1092 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1093 }
1094 }
1095
1096 if (mh->is_shared()) {
1097 assert(mh->adapter() == adapter, "must be");
1098 assert(mh->_from_compiled_entry != NULL, "must be");
1099 } else {
1100 mh->set_adapter_entry(adapter);
1101 mh->_from_compiled_entry = adapter->get_c2i_entry();
1102 }
1103 return adapter->get_c2i_entry();
1104 }
1105
1106 void Method::restore_unshareable_info(TRAPS) {
1107 assert(is_method() && is_valid_method(), "ensure C++ vtable is restored");
1108
1109 // Since restore_unshareable_info can be called more than once for a method, don't
1110 // redo any work.
1111 if (adapter() == NULL) {
1112 methodHandle mh(THREAD, this);
1113 link_method(mh, CHECK);
1114 }
1115 }
1116
1117 address Method::from_compiled_entry_no_trampoline() const {
1118 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1119 if (code) {
1120 return code->verified_entry_point();
1121 } else {
1122 return adapter()->get_c2i_entry();
1123 }
1124 }
1125
1126 // The verified_code_entry() must be called when a invoke is resolved
1127 // on this method.
1128
1129 // It returns the compiled code entry point, after asserting not null.
1130 // This function is called after potential safepoints so that nmethod
1131 // or adapter that it points to is still live and valid.
1132 // This function must not hit a safepoint!
1133 address Method::verified_code_entry() {
1134 debug_only(NoSafepointVerifier nsv;)
1135 assert(_from_compiled_entry != NULL, "must be set");
1136 return _from_compiled_entry;
1137 }
1138
1139 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1140 // (could be racing a deopt).
1141 // Not inline to avoid circular ref.
1142 bool Method::check_code() const {
1143 // cached in a register or local. There's a race on the value of the field.
1144 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1145 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1146 }
1147
1148 // Install compiled code. Instantly it can execute.
1149 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1150 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1151 assert( code, "use clear_code to remove code" );
1152 assert( mh->check_code(), "" );
1153
1154 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1155
1156 // These writes must happen in this order, because the interpreter will
1157 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1158 // which jumps to _from_compiled_entry.
1159 mh->_code = code; // Assign before allowing compiled code to exec
1160
1161 int comp_level = code->comp_level();
1162 // In theory there could be a race here. In practice it is unlikely
1163 // and not worth worrying about.
1164 if (comp_level > mh->highest_comp_level()) {
1165 mh->set_highest_comp_level(comp_level);
1166 }
1167
1168 OrderAccess::storestore();
1169 mh->_from_compiled_entry = code->verified_entry_point();
1170 OrderAccess::storestore();
1171 // Instantly compiled code can execute.
1172 if (!mh->is_method_handle_intrinsic())
1173 mh->_from_interpreted_entry = mh->get_i2c_entry();
1174 }
1175
1176
1177 bool Method::is_overridden_in(Klass* k) const {
1178 InstanceKlass* ik = InstanceKlass::cast(k);
1179
1180 if (ik->is_interface()) return false;
1181
1182 // If method is an interface, we skip it - except if it
1183 // is a miranda method
1184 if (method_holder()->is_interface()) {
1185 // Check that method is not a miranda method
1186 if (ik->lookup_method(name(), signature()) == NULL) {
1187 // No implementation exist - so miranda method
1188 return false;
1189 }
1190 return true;
1191 }
1192
1193 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1194 if (!has_vtable_index()) {
1195 return false;
1196 } else {
1197 Method* vt_m = ik->method_at_vtable(vtable_index());
1198 return vt_m != this;
1199 }
1200 }
1201
1202
1203 // give advice about whether this Method* should be cached or not
1204 bool Method::should_not_be_cached() const {
1205 if (is_old()) {
1206 // This method has been redefined. It is either EMCP or obsolete
1207 // and we don't want to cache it because that would pin the method
1208 // down and prevent it from being collectible if and when it
1209 // finishes executing.
1210 return true;
1211 }
1212
1213 // caching this method should be just fine
1214 return false;
1215 }
1216
1217
1218 /**
1219 * Returns true if this is one of the specially treated methods for
1220 * security related stack walks (like Reflection.getCallerClass).
1221 */
1222 bool Method::is_ignored_by_security_stack_walk() const {
1223 if (intrinsic_id() == vmIntrinsics::_invoke) {
1224 // This is Method.invoke() -- ignore it
1225 return true;
1226 }
1227 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1228 // This is an auxilary frame -- ignore it
1229 return true;
1230 }
1231 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1232 // This is an internal adapter frame for method handles -- ignore it
1233 return true;
1234 }
1235 return false;
1236 }
1237
1238
1239 // Constant pool structure for invoke methods:
1240 enum {
1241 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1242 _imcp_invoke_signature, // utf8: (variable Symbol*)
1243 _imcp_limit
1244 };
1245
1246 // Test if this method is an MH adapter frame generated by Java code.
1247 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1248 bool Method::is_compiled_lambda_form() const {
1249 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1250 }
1251
1252 // Test if this method is an internal MH primitive method.
1253 bool Method::is_method_handle_intrinsic() const {
1254 vmIntrinsics::ID iid = intrinsic_id();
1255 return (MethodHandles::is_signature_polymorphic(iid) &&
1256 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1257 }
1258
1259 bool Method::has_member_arg() const {
1260 vmIntrinsics::ID iid = intrinsic_id();
1261 return (MethodHandles::is_signature_polymorphic(iid) &&
1262 MethodHandles::has_member_arg(iid));
1263 }
1264
1265 // Make an instance of a signature-polymorphic internal MH primitive.
1266 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1267 Symbol* signature,
1268 TRAPS) {
1269 ResourceMark rm;
1270 methodHandle empty;
1271
1272 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1273 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1274 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1275 if (TraceMethodHandles) {
1276 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1277 }
1278
1279 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1280 name->increment_refcount();
1281 signature->increment_refcount();
1282
1283 int cp_length = _imcp_limit;
1284 ClassLoaderData* loader_data = holder->class_loader_data();
1285 constantPoolHandle cp;
1286 {
1287 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1288 cp = constantPoolHandle(THREAD, cp_oop);
1289 }
1290 cp->set_pool_holder(holder);
1291 cp->symbol_at_put(_imcp_invoke_name, name);
1292 cp->symbol_at_put(_imcp_invoke_signature, signature);
1293 cp->set_has_preresolution();
1294
1295 // decide on access bits: public or not?
1296 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1297 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1298 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1299 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1300
1301 methodHandle m;
1302 {
1303 InlineTableSizes sizes;
1304 Method* m_oop = Method::allocate(loader_data, 0,
1305 accessFlags_from(flags_bits), &sizes,
1306 ConstMethod::NORMAL, CHECK_(empty));
1307 m = methodHandle(THREAD, m_oop);
1308 }
1309 m->set_constants(cp());
1310 m->set_name_index(_imcp_invoke_name);
1311 m->set_signature_index(_imcp_invoke_signature);
1312 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1313 assert(m->signature() == signature, "");
1314 ResultTypeFinder rtf(signature);
1315 m->constMethod()->set_result_type(rtf.type());
1316 m->compute_size_of_parameters(THREAD);
1317 m->init_intrinsic_id();
1318 assert(m->is_method_handle_intrinsic(), "");
1319 #ifdef ASSERT
1320 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1321 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1322 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1323 #endif //ASSERT
1324
1325 // Finally, set up its entry points.
1326 assert(m->can_be_statically_bound(), "");
1327 m->set_vtable_index(Method::nonvirtual_vtable_index);
1328 m->link_method(m, CHECK_(empty));
1329
1330 if (TraceMethodHandles && (Verbose || WizardMode)) {
1331 ttyLocker ttyl;
1332 m->print_on(tty);
1333 }
1334
1335 return m;
1336 }
1337
1338 Klass* Method::check_non_bcp_klass(Klass* klass) {
1339 if (klass != NULL && klass->class_loader() != NULL) {
1340 if (klass->is_objArray_klass())
1341 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1342 return klass;
1343 }
1344 return NULL;
1345 }
1346
1347
1348 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1349 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1350 // Code below does not work for native methods - they should never get rewritten anyway
1351 assert(!m->is_native(), "cannot rewrite native methods");
1352 // Allocate new Method*
1353 AccessFlags flags = m->access_flags();
1354
1355 ConstMethod* cm = m->constMethod();
1356 int checked_exceptions_len = cm->checked_exceptions_length();
1357 int localvariable_len = cm->localvariable_table_length();
1358 int exception_table_len = cm->exception_table_length();
1359 int method_parameters_len = cm->method_parameters_length();
1360 int method_annotations_len = cm->method_annotations_length();
1361 int parameter_annotations_len = cm->parameter_annotations_length();
1362 int type_annotations_len = cm->type_annotations_length();
1363 int default_annotations_len = cm->default_annotations_length();
1364
1365 InlineTableSizes sizes(
1366 localvariable_len,
1367 new_compressed_linenumber_size,
1368 exception_table_len,
1369 checked_exceptions_len,
1370 method_parameters_len,
1371 cm->generic_signature_index(),
1372 method_annotations_len,
1373 parameter_annotations_len,
1374 type_annotations_len,
1375 default_annotations_len,
1376 0);
1377
1378 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1379 Method* newm_oop = Method::allocate(loader_data,
1380 new_code_length,
1381 flags,
1382 &sizes,
1383 m->method_type(),
1384 CHECK_(methodHandle()));
1385 methodHandle newm (THREAD, newm_oop);
1386
1387 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1388 ConstMethod* newcm = newm->constMethod();
1389 int new_const_method_size = newm->constMethod()->size();
1390
1391 // This works because the source and target are both Methods. Some compilers
1392 // (e.g., clang) complain that the target vtable pointer will be stomped,
1393 // so cast away newm()'s and m()'s Methodness.
1394 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1395
1396 // Create shallow copy of ConstMethod.
1397 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1398
1399 // Reset correct method/const method, method size, and parameter info
1400 newm->set_constMethod(newcm);
1401 newm->constMethod()->set_code_size(new_code_length);
1402 newm->constMethod()->set_constMethod_size(new_const_method_size);
1403 assert(newm->code_size() == new_code_length, "check");
1404 assert(newm->method_parameters_length() == method_parameters_len, "check");
1405 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1406 assert(newm->exception_table_length() == exception_table_len, "check");
1407 assert(newm->localvariable_table_length() == localvariable_len, "check");
1408 // Copy new byte codes
1409 memcpy(newm->code_base(), new_code, new_code_length);
1410 // Copy line number table
1411 if (new_compressed_linenumber_size > 0) {
1412 memcpy(newm->compressed_linenumber_table(),
1413 new_compressed_linenumber_table,
1414 new_compressed_linenumber_size);
1415 }
1416 // Copy method_parameters
1417 if (method_parameters_len > 0) {
1418 memcpy(newm->method_parameters_start(),
1419 m->method_parameters_start(),
1420 method_parameters_len * sizeof(MethodParametersElement));
1421 }
1422 // Copy checked_exceptions
1423 if (checked_exceptions_len > 0) {
1424 memcpy(newm->checked_exceptions_start(),
1425 m->checked_exceptions_start(),
1426 checked_exceptions_len * sizeof(CheckedExceptionElement));
1427 }
1428 // Copy exception table
1429 if (exception_table_len > 0) {
1430 memcpy(newm->exception_table_start(),
1431 m->exception_table_start(),
1432 exception_table_len * sizeof(ExceptionTableElement));
1433 }
1434 // Copy local variable number table
1435 if (localvariable_len > 0) {
1436 memcpy(newm->localvariable_table_start(),
1437 m->localvariable_table_start(),
1438 localvariable_len * sizeof(LocalVariableTableElement));
1439 }
1440 // Copy stackmap table
1441 if (m->has_stackmap_table()) {
1442 int code_attribute_length = m->stackmap_data()->length();
1443 Array<u1>* stackmap_data =
1444 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1445 memcpy((void*)stackmap_data->adr_at(0),
1446 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1447 newm->set_stackmap_data(stackmap_data);
1448 }
1449
1450 // copy annotations over to new method
1451 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1452 return newm;
1453 }
1454
1455 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1456 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1457 // because we are not loading from core libraries
1458 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1459 // which does not use the class default class loader so we check for its loader here
1460 const InstanceKlass* ik = InstanceKlass::cast(holder);
1461 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1462 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1463 }
1464
1465 // see if the klass name is well-known:
1466 Symbol* klass_name = ik->name();
1467 return vmSymbols::find_sid(klass_name);
1468 }
1469
1470 void Method::init_intrinsic_id() {
1471 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1472 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1473 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1474 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1475
1476 // the klass name is well-known:
1477 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1478 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1479
1480 // ditto for method and signature:
1481 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1482 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1483 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1484 && name_id == vmSymbols::NO_SID) {
1485 return;
1486 }
1487 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1488 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1489 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1490 && sig_id == vmSymbols::NO_SID) {
1491 return;
1492 }
1493 jshort flags = access_flags().as_short();
1494
1495 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1496 if (id != vmIntrinsics::_none) {
1497 set_intrinsic_id(id);
1498 if (id == vmIntrinsics::_Class_cast) {
1499 // Even if the intrinsic is rejected, we want to inline this simple method.
1500 set_force_inline(true);
1501 }
1502 return;
1503 }
1504
1505 // A few slightly irregular cases:
1506 switch (klass_id) {
1507 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1508 // Second chance: check in regular Math.
1509 switch (name_id) {
1510 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1511 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1512 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1513 // pretend it is the corresponding method in the non-strict class:
1514 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1515 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1516 break;
1517 default:
1518 break;
1519 }
1520 break;
1521
1522 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1523 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1524 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1525 if (!is_native()) break;
1526 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1527 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1528 id = vmIntrinsics::_none;
1529 break;
1530
1531 default:
1532 break;
1533 }
1534
1535 if (id != vmIntrinsics::_none) {
1536 // Set up its iid. It is an alias method.
1537 set_intrinsic_id(id);
1538 return;
1539 }
1540 }
1541
1542 // These two methods are static since a GC may move the Method
1543 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1544 if (!THREAD->can_call_java()) {
1545 // There is nothing useful this routine can do from within the Compile thread.
1546 // Hopefully, the signature contains only well-known classes.
1547 // We could scan for this and return true/false, but the caller won't care.
1548 return false;
1549 }
1550 bool sig_is_loaded = true;
1551 Handle class_loader(THREAD, m->method_holder()->class_loader());
1552 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1553 ResourceMark rm(THREAD);
1554 Symbol* signature = m->signature();
1555 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1556 if (ss.is_object()) {
1557 Symbol* sym = ss.as_symbol(CHECK_(false));
1558 Symbol* name = sym;
1559 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1560 protection_domain, THREAD);
1561 // We are loading classes eagerly. If a ClassNotFoundException or
1562 // a LinkageError was generated, be sure to ignore it.
1563 if (HAS_PENDING_EXCEPTION) {
1564 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1565 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1566 CLEAR_PENDING_EXCEPTION;
1567 } else {
1568 return false;
1569 }
1570 }
1571 if( klass == NULL) { sig_is_loaded = false; }
1572 }
1573 }
1574 return sig_is_loaded;
1575 }
1576
1577 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1578 Handle class_loader(THREAD, m->method_holder()->class_loader());
1579 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1580 ResourceMark rm(THREAD);
1581 Symbol* signature = m->signature();
1582 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1583 if (ss.type() == T_OBJECT) {
1584 Symbol* name = ss.as_symbol_or_null();
1585 if (name == NULL) return true;
1586 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1587 if (klass == NULL) return true;
1588 }
1589 }
1590 return false;
1591 }
1592
1593 // Exposed so field engineers can debug VM
1594 void Method::print_short_name(outputStream* st) {
1595 ResourceMark rm;
1596 #ifdef PRODUCT
1597 st->print(" %s::", method_holder()->external_name());
1598 #else
1599 st->print(" %s::", method_holder()->internal_name());
1600 #endif
1601 name()->print_symbol_on(st);
1602 if (WizardMode) signature()->print_symbol_on(st);
1603 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1604 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1605 }
1606
1607 // Comparer for sorting an object array containing
1608 // Method*s.
1609 static int method_comparator(Method* a, Method* b) {
1610 return a->name()->fast_compare(b->name());
1611 }
1612
1613 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1614 // default_methods also uses this without the ordering for fast find_method
1615 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1616 int length = methods->length();
1617 if (length > 1) {
1618 {
1619 NoSafepointVerifier nsv;
1620 QuickSort::sort(methods->data(), length, method_comparator, idempotent);
1621 }
1622 // Reset method ordering
1623 if (set_idnums) {
1624 for (int i = 0; i < length; i++) {
1625 Method* m = methods->at(i);
1626 m->set_method_idnum(i);
1627 m->set_orig_method_idnum(i);
1628 }
1629 }
1630 }
1631 }
1632
1633 //-----------------------------------------------------------------------------------
1634 // Non-product code unless JVM/TI needs it
1635
1636 #if !defined(PRODUCT) || INCLUDE_JVMTI
1637 class SignatureTypePrinter : public SignatureTypeNames {
1638 private:
1639 outputStream* _st;
1640 bool _use_separator;
1641
1642 void type_name(const char* name) {
1643 if (_use_separator) _st->print(", ");
1644 _st->print("%s", name);
1645 _use_separator = true;
1646 }
1647
1648 public:
1649 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1650 _st = st;
1651 _use_separator = false;
1652 }
1653
1654 void print_parameters() { _use_separator = false; iterate_parameters(); }
1655 void print_returntype() { _use_separator = false; iterate_returntype(); }
1656 };
1657
1658
1659 void Method::print_name(outputStream* st) {
1660 Thread *thread = Thread::current();
1661 ResourceMark rm(thread);
1662 st->print("%s ", is_static() ? "static" : "virtual");
1663 if (WizardMode) {
1664 st->print("%s.", method_holder()->internal_name());
1665 name()->print_symbol_on(st);
1666 signature()->print_symbol_on(st);
1667 } else {
1668 SignatureTypePrinter sig(signature(), st);
1669 sig.print_returntype();
1670 st->print(" %s.", method_holder()->internal_name());
1671 name()->print_symbol_on(st);
1672 st->print("(");
1673 sig.print_parameters();
1674 st->print(")");
1675 }
1676 }
1677 #endif // !PRODUCT || INCLUDE_JVMTI
1678
1679
1680 void Method::print_codes_on(outputStream* st) const {
1681 print_codes_on(0, code_size(), st);
1682 }
1683
1684 void Method::print_codes_on(int from, int to, outputStream* st) const {
1685 Thread *thread = Thread::current();
1686 ResourceMark rm(thread);
1687 methodHandle mh (thread, (Method*)this);
1688 BytecodeStream s(mh);
1689 s.set_interval(from, to);
1690 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1691 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1692 }
1693
1694
1695 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1696 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1697 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1698 // as end-of-stream terminator.
1699
1700 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1701 // bci and line number does not compress into single byte.
1702 // Write out escape character and use regular compression for bci and line number.
1703 write_byte((jubyte)0xFF);
1704 write_signed_int(bci_delta);
1705 write_signed_int(line_delta);
1706 }
1707
1708 // See comment in method.hpp which explains why this exists.
1709 #if defined(_M_AMD64) && _MSC_VER >= 1400
1710 #pragma optimize("", off)
1711 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1712 write_pair_inline(bci, line);
1713 }
1714 #pragma optimize("", on)
1715 #endif
1716
1717 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1718 _bci = 0;
1719 _line = 0;
1720 };
1721
1722
1723 bool CompressedLineNumberReadStream::read_pair() {
1724 jubyte next = read_byte();
1725 // Check for terminator
1726 if (next == 0) return false;
1727 if (next == 0xFF) {
1728 // Escape character, regular compression used
1729 _bci += read_signed_int();
1730 _line += read_signed_int();
1731 } else {
1732 // Single byte compression used
1733 _bci += next >> 3;
1734 _line += next & 0x7;
1735 }
1736 return true;
1737 }
1738
1739 #if INCLUDE_JVMTI
1740
1741 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1742 BreakpointInfo* bp = method_holder()->breakpoints();
1743 for (; bp != NULL; bp = bp->next()) {
1744 if (bp->match(this, bci)) {
1745 return bp->orig_bytecode();
1746 }
1747 }
1748 {
1749 ResourceMark rm;
1750 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1751 }
1752 return Bytecodes::_shouldnotreachhere;
1753 }
1754
1755 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1756 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1757 BreakpointInfo* bp = method_holder()->breakpoints();
1758 for (; bp != NULL; bp = bp->next()) {
1759 if (bp->match(this, bci)) {
1760 bp->set_orig_bytecode(code);
1761 // and continue, in case there is more than one
1762 }
1763 }
1764 }
1765
1766 void Method::set_breakpoint(int bci) {
1767 InstanceKlass* ik = method_holder();
1768 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1769 bp->set_next(ik->breakpoints());
1770 ik->set_breakpoints(bp);
1771 // do this last:
1772 bp->set(this);
1773 }
1774
1775 static void clear_matches(Method* m, int bci) {
1776 InstanceKlass* ik = m->method_holder();
1777 BreakpointInfo* prev_bp = NULL;
1778 BreakpointInfo* next_bp;
1779 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1780 next_bp = bp->next();
1781 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1782 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1783 // do this first:
1784 bp->clear(m);
1785 // unhook it
1786 if (prev_bp != NULL)
1787 prev_bp->set_next(next_bp);
1788 else
1789 ik->set_breakpoints(next_bp);
1790 delete bp;
1791 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1792 // at same location. So we have multiple matching (method_index and bci)
1793 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1794 // breakpoint for clear_breakpoint request and keep all other method versions
1795 // BreakpointInfo for future clear_breakpoint request.
1796 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1797 // which is being called when class is unloaded. We delete all the Breakpoint
1798 // information for all versions of method. We may not correctly restore the original
1799 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1800 // so these methods won't be used anymore.
1801 if (bci >= 0) {
1802 break;
1803 }
1804 } else {
1805 // This one is a keeper.
1806 prev_bp = bp;
1807 }
1808 }
1809 }
1810
1811 void Method::clear_breakpoint(int bci) {
1812 assert(bci >= 0, "");
1813 clear_matches(this, bci);
1814 }
1815
1816 void Method::clear_all_breakpoints() {
1817 clear_matches(this, -1);
1818 }
1819
1820 #endif // INCLUDE_JVMTI
1821
1822 int Method::invocation_count() {
1823 MethodCounters *mcs = method_counters();
1824 if (TieredCompilation) {
1825 MethodData* const mdo = method_data();
1826 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1827 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1828 return InvocationCounter::count_limit;
1829 } else {
1830 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1831 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1832 }
1833 } else {
1834 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1835 }
1836 }
1837
1838 int Method::backedge_count() {
1839 MethodCounters *mcs = method_counters();
1840 if (TieredCompilation) {
1841 MethodData* const mdo = method_data();
1842 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1843 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1844 return InvocationCounter::count_limit;
1845 } else {
1846 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1847 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1848 }
1849 } else {
1850 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1851 }
1852 }
1853
1854 int Method::highest_comp_level() const {
1855 const MethodCounters* mcs = method_counters();
1856 if (mcs != NULL) {
1857 return mcs->highest_comp_level();
1858 } else {
1859 return CompLevel_none;
1860 }
1861 }
1862
1863 int Method::highest_osr_comp_level() const {
1864 const MethodCounters* mcs = method_counters();
1865 if (mcs != NULL) {
1866 return mcs->highest_osr_comp_level();
1867 } else {
1868 return CompLevel_none;
1869 }
1870 }
1871
1872 void Method::set_highest_comp_level(int level) {
1873 MethodCounters* mcs = method_counters();
1874 if (mcs != NULL) {
1875 mcs->set_highest_comp_level(level);
1876 }
1877 }
1878
1879 void Method::set_highest_osr_comp_level(int level) {
1880 MethodCounters* mcs = method_counters();
1881 if (mcs != NULL) {
1882 mcs->set_highest_osr_comp_level(level);
1883 }
1884 }
1885
1886 #if INCLUDE_JVMTI
1887
1888 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1889 _bci = bci;
1890 _name_index = m->name_index();
1891 _signature_index = m->signature_index();
1892 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1893 if (_orig_bytecode == Bytecodes::_breakpoint)
1894 _orig_bytecode = m->orig_bytecode_at(_bci);
1895 _next = NULL;
1896 }
1897
1898 void BreakpointInfo::set(Method* method) {
1899 #ifdef ASSERT
1900 {
1901 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1902 if (code == Bytecodes::_breakpoint)
1903 code = method->orig_bytecode_at(_bci);
1904 assert(orig_bytecode() == code, "original bytecode must be the same");
1905 }
1906 #endif
1907 Thread *thread = Thread::current();
1908 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1909 method->incr_number_of_breakpoints(thread);
1910 SystemDictionary::notice_modification();
1911 {
1912 // Deoptimize all dependents on this method
1913 HandleMark hm(thread);
1914 methodHandle mh(thread, method);
1915 CodeCache::flush_dependents_on_method(mh);
1916 }
1917 }
1918
1919 void BreakpointInfo::clear(Method* method) {
1920 *method->bcp_from(_bci) = orig_bytecode();
1921 assert(method->number_of_breakpoints() > 0, "must not go negative");
1922 method->decr_number_of_breakpoints(Thread::current());
1923 }
1924
1925 #endif // INCLUDE_JVMTI
1926
1927 // jmethodID handling
1928
1929 // This is a block allocating object, sort of like JNIHandleBlock, only a
1930 // lot simpler.
1931 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1932 // never get rid of it.
1933
1934 static const int min_block_size = 8;
1935
1936 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1937 friend class JNIMethodBlock;
1938 Method** _methods;
1939 int _number_of_methods;
1940 int _top;
1941 JNIMethodBlockNode* _next;
1942
1943 public:
1944
1945 JNIMethodBlockNode(int num_methods = min_block_size);
1946
1947 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1948
1949 void ensure_methods(int num_addl_methods) {
1950 if (_top < _number_of_methods) {
1951 num_addl_methods -= _number_of_methods - _top;
1952 if (num_addl_methods <= 0) {
1953 return;
1954 }
1955 }
1956 if (_next == NULL) {
1957 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1958 } else {
1959 _next->ensure_methods(num_addl_methods);
1960 }
1961 }
1962 };
1963
1964 class JNIMethodBlock : public CHeapObj<mtClass> {
1965 JNIMethodBlockNode _head;
1966 JNIMethodBlockNode *_last_free;
1967 public:
1968 static Method* const _free_method;
1969
1970 JNIMethodBlock(int initial_capacity = min_block_size)
1971 : _head(initial_capacity), _last_free(&_head) {}
1972
1973 void ensure_methods(int num_addl_methods) {
1974 _last_free->ensure_methods(num_addl_methods);
1975 }
1976
1977 Method** add_method(Method* m) {
1978 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1979 if (b->_top < b->_number_of_methods) {
1980 // top points to the next free entry.
1981 int i = b->_top;
1982 b->_methods[i] = m;
1983 b->_top++;
1984 _last_free = b;
1985 return &(b->_methods[i]);
1986 } else if (b->_top == b->_number_of_methods) {
1987 // if the next free entry ran off the block see if there's a free entry
1988 for (int i = 0; i < b->_number_of_methods; i++) {
1989 if (b->_methods[i] == _free_method) {
1990 b->_methods[i] = m;
1991 _last_free = b;
1992 return &(b->_methods[i]);
1993 }
1994 }
1995 // Only check each block once for frees. They're very unlikely.
1996 // Increment top past the end of the block.
1997 b->_top++;
1998 }
1999 // need to allocate a next block.
2000 if (b->_next == NULL) {
2001 b->_next = _last_free = new JNIMethodBlockNode();
2002 }
2003 }
2004 guarantee(false, "Should always allocate a free block");
2005 return NULL;
2006 }
2007
2008 bool contains(Method** m) {
2009 if (m == NULL) return false;
2010 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2011 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2012 // This is a bit of extra checking, for two reasons. One is
2013 // that contains() deals with pointers that are passed in by
2014 // JNI code, so making sure that the pointer is aligned
2015 // correctly is valuable. The other is that <= and > are
2016 // technically not defined on pointers, so the if guard can
2017 // pass spuriously; no modern compiler is likely to make that
2018 // a problem, though (and if one did, the guard could also
2019 // fail spuriously, which would be bad).
2020 ptrdiff_t idx = m - b->_methods;
2021 if (b->_methods + idx == m) {
2022 return true;
2023 }
2024 }
2025 }
2026 return false; // not found
2027 }
2028
2029 // Doesn't really destroy it, just marks it as free so it can be reused.
2030 void destroy_method(Method** m) {
2031 #ifdef ASSERT
2032 assert(contains(m), "should be a methodID");
2033 #endif // ASSERT
2034 *m = _free_method;
2035 }
2036
2037 // During class unloading the methods are cleared, which is different
2038 // than freed.
2039 void clear_all_methods() {
2040 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2041 for (int i = 0; i< b->_number_of_methods; i++) {
2042 b->_methods[i] = NULL;
2043 }
2044 }
2045 }
2046 #ifndef PRODUCT
2047 int count_methods() {
2048 // count all allocated methods
2049 int count = 0;
2050 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2051 for (int i = 0; i< b->_number_of_methods; i++) {
2052 if (b->_methods[i] != _free_method) count++;
2053 }
2054 }
2055 return count;
2056 }
2057 #endif // PRODUCT
2058 };
2059
2060 // Something that can't be mistaken for an address or a markOop
2061 Method* const JNIMethodBlock::_free_method = (Method*)55;
2062
2063 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) {
2064 _number_of_methods = MAX2(num_methods, min_block_size);
2065 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2066 for (int i = 0; i < _number_of_methods; i++) {
2067 _methods[i] = JNIMethodBlock::_free_method;
2068 }
2069 }
2070
2071 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2072 ClassLoaderData* cld = loader_data;
2073 if (!SafepointSynchronize::is_at_safepoint()) {
2074 // Have to add jmethod_ids() to class loader data thread-safely.
2075 // Also have to add the method to the list safely, which the cld lock
2076 // protects as well.
2077 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2078 if (cld->jmethod_ids() == NULL) {
2079 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2080 } else {
2081 cld->jmethod_ids()->ensure_methods(capacity);
2082 }
2083 } else {
2084 // At safepoint, we are single threaded and can set this.
2085 if (cld->jmethod_ids() == NULL) {
2086 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2087 } else {
2088 cld->jmethod_ids()->ensure_methods(capacity);
2089 }
2090 }
2091 }
2092
2093 // Add a method id to the jmethod_ids
2094 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2095 ClassLoaderData* cld = loader_data;
2096
2097 if (!SafepointSynchronize::is_at_safepoint()) {
2098 // Have to add jmethod_ids() to class loader data thread-safely.
2099 // Also have to add the method to the list safely, which the cld lock
2100 // protects as well.
2101 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2102 if (cld->jmethod_ids() == NULL) {
2103 cld->set_jmethod_ids(new JNIMethodBlock());
2104 }
2105 // jmethodID is a pointer to Method*
2106 return (jmethodID)cld->jmethod_ids()->add_method(m);
2107 } else {
2108 // At safepoint, we are single threaded and can set this.
2109 if (cld->jmethod_ids() == NULL) {
2110 cld->set_jmethod_ids(new JNIMethodBlock());
2111 }
2112 // jmethodID is a pointer to Method*
2113 return (jmethodID)cld->jmethod_ids()->add_method(m);
2114 }
2115 }
2116
2117 // Mark a jmethodID as free. This is called when there is a data race in
2118 // InstanceKlass while creating the jmethodID cache.
2119 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2120 ClassLoaderData* cld = loader_data;
2121 Method** ptr = (Method**)m;
2122 assert(cld->jmethod_ids() != NULL, "should have method handles");
2123 cld->jmethod_ids()->destroy_method(ptr);
2124 }
2125
2126 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2127 // Can't assert the method_holder is the same because the new method has the
2128 // scratch method holder.
2129 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2130 == new_method->method_holder()->class_loader(),
2131 "changing to a different class loader");
2132 // Just change the method in place, jmethodID pointer doesn't change.
2133 *((Method**)jmid) = new_method;
2134 }
2135
2136 bool Method::is_method_id(jmethodID mid) {
2137 Method* m = resolve_jmethod_id(mid);
2138 assert(m != NULL, "should be called with non-null method");
2139 InstanceKlass* ik = m->method_holder();
2140 ClassLoaderData* cld = ik->class_loader_data();
2141 if (cld->jmethod_ids() == NULL) return false;
2142 return (cld->jmethod_ids()->contains((Method**)mid));
2143 }
2144
2145 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2146 if (mid == NULL) return NULL;
2147 Method* o = resolve_jmethod_id(mid);
2148 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2149 return NULL;
2150 }
2151 return o;
2152 };
2153
2154 void Method::set_on_stack(const bool value) {
2155 // Set both the method itself and its constant pool. The constant pool
2156 // on stack means some method referring to it is also on the stack.
2157 constants()->set_on_stack(value);
2158
2159 bool already_set = on_stack();
2160 _access_flags.set_on_stack(value);
2161 if (value && !already_set) {
2162 MetadataOnStackMark::record(this);
2163 }
2164 }
2165
2166 // Called when the class loader is unloaded to make all methods weak.
2167 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2168 loader_data->jmethod_ids()->clear_all_methods();
2169 }
2170
2171 bool Method::has_method_vptr(const void* ptr) {
2172 Method m;
2173 // This assumes that the vtbl pointer is the first word of a C++ object.
2174 return dereference_vptr(&m) == dereference_vptr(ptr);
2175 }
2176
2177 // Check that this pointer is valid by checking that the vtbl pointer matches
2178 bool Method::is_valid_method() const {
2179 if (this == NULL) {
2180 return false;
2181 } else if ((intptr_t(this) & (wordSize-1)) != 0) {
2182 // Quick sanity check on pointer.
2183 return false;
2184 } else if (is_shared()) {
2185 return MetaspaceShared::is_valid_shared_method(this);
2186 } else if (Metaspace::contains_non_shared(this)) {
2187 return has_method_vptr((const void*)this);
2188 } else {
2189 return false;
2190 }
2191 }
2192
2193 #ifndef PRODUCT
2194 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2195 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2196 }
2197 #endif // PRODUCT
2198
2199
2200 // Printing
2201
2202 #ifndef PRODUCT
2203
2204 void Method::print_on(outputStream* st) const {
2205 ResourceMark rm;
2206 assert(is_method(), "must be method");
2207 st->print_cr("%s", internal_name());
2208 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2209 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2210 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2211 constants()->print_value_on(st); st->cr();
2212 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2213 st->print (" - name: "); name()->print_value_on(st); st->cr();
2214 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2215 st->print_cr(" - max stack: %d", max_stack());
2216 st->print_cr(" - max locals: %d", max_locals());
2217 st->print_cr(" - size of params: %d", size_of_parameters());
2218 st->print_cr(" - method size: %d", method_size());
2219 if (intrinsic_id() != vmIntrinsics::_none)
2220 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2221 if (highest_comp_level() != CompLevel_none)
2222 st->print_cr(" - highest level: %d", highest_comp_level());
2223 st->print_cr(" - vtable index: %d", _vtable_index);
2224 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2225 st->print( " - adapters: ");
2226 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2227 if (a == NULL)
2228 st->print_cr(INTPTR_FORMAT, p2i(a));
2229 else
2230 a->print_adapter_on(st);
2231 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2232 st->print_cr(" - code size: %d", code_size());
2233 if (code_size() != 0) {
2234 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2235 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2236 }
2237 if (method_data() != NULL) {
2238 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2239 }
2240 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2241 if (checked_exceptions_length() > 0) {
2242 CheckedExceptionElement* table = checked_exceptions_start();
2243 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2244 if (Verbose) {
2245 for (int i = 0; i < checked_exceptions_length(); i++) {
2246 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2247 }
2248 }
2249 }
2250 if (has_linenumber_table()) {
2251 u_char* table = compressed_linenumber_table();
2252 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2253 if (Verbose) {
2254 CompressedLineNumberReadStream stream(table);
2255 while (stream.read_pair()) {
2256 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2257 }
2258 }
2259 }
2260 st->print_cr(" - localvar length: %d", localvariable_table_length());
2261 if (localvariable_table_length() > 0) {
2262 LocalVariableTableElement* table = localvariable_table_start();
2263 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2264 if (Verbose) {
2265 for (int i = 0; i < localvariable_table_length(); i++) {
2266 int bci = table[i].start_bci;
2267 int len = table[i].length;
2268 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2269 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2270 int slot = table[i].slot;
2271 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2272 }
2273 }
2274 }
2275 if (code() != NULL) {
2276 st->print (" - compiled code: ");
2277 code()->print_value_on(st);
2278 }
2279 if (is_native()) {
2280 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2281 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2282 }
2283 }
2284
2285 void Method::print_linkage_flags(outputStream* st) {
2286 access_flags().print_on(st);
2287 if (is_default_method()) {
2288 st->print("default ");
2289 }
2290 if (is_overpass()) {
2291 st->print("overpass ");
2292 }
2293 }
2294 #endif //PRODUCT
2295
2296 void Method::print_value_on(outputStream* st) const {
2297 assert(is_method(), "must be method");
2298 st->print("%s", internal_name());
2299 print_address_on(st);
2300 st->print(" ");
2301 name()->print_value_on(st);
2302 st->print(" ");
2303 signature()->print_value_on(st);
2304 st->print(" in ");
2305 method_holder()->print_value_on(st);
2306 if (WizardMode) st->print("#%d", _vtable_index);
2307 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2308 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2309 }
2310
2311 #if INCLUDE_SERVICES
2312 // Size Statistics
2313 void Method::collect_statistics(KlassSizeStats *sz) const {
2314 int mysize = sz->count(this);
2315 sz->_method_bytes += mysize;
2316 sz->_method_all_bytes += mysize;
2317 sz->_rw_bytes += mysize;
2318
2319 if (constMethod()) {
2320 constMethod()->collect_statistics(sz);
2321 }
2322 if (method_data()) {
2323 method_data()->collect_statistics(sz);
2324 }
2325 }
2326 #endif // INCLUDE_SERVICES
2327
2328 // LogTouchedMethods and PrintTouchedMethods
2329
2330 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2331 // the Method may be garbage collected. Let's roll our own hash table.
2332 class TouchedMethodRecord : CHeapObj<mtTracing> {
2333 public:
2334 // It's OK to store Symbols here because they will NOT be GC'ed if
2335 // LogTouchedMethods is enabled.
2336 TouchedMethodRecord* _next;
2337 Symbol* _class_name;
2338 Symbol* _method_name;
2339 Symbol* _method_signature;
2340 };
2341
2342 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2343 static TouchedMethodRecord** _touched_method_table = NULL;
2344
2345 void Method::log_touched(TRAPS) {
2346
2347 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2348 Symbol* my_class = klass_name();
2349 Symbol* my_name = name();
2350 Symbol* my_sig = signature();
2351
2352 unsigned int hash = my_class->identity_hash() +
2353 my_name->identity_hash() +
2354 my_sig->identity_hash();
2355 juint index = juint(hash) % table_size;
2356
2357 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2358 if (_touched_method_table == NULL) {
2359 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2360 mtTracing, CURRENT_PC);
2361 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2362 }
2363
2364 TouchedMethodRecord* ptr = _touched_method_table[index];
2365 while (ptr) {
2366 if (ptr->_class_name == my_class &&
2367 ptr->_method_name == my_name &&
2368 ptr->_method_signature == my_sig) {
2369 return;
2370 }
2371 if (ptr->_next == NULL) break;
2372 ptr = ptr->_next;
2373 }
2374 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2375 my_class->set_permanent(); // prevent reclaimed by GC
2376 my_name->set_permanent();
2377 my_sig->set_permanent();
2378 nptr->_class_name = my_class;
2379 nptr->_method_name = my_name;
2380 nptr->_method_signature = my_sig;
2381 nptr->_next = NULL;
2382
2383 if (ptr == NULL) {
2384 // first
2385 _touched_method_table[index] = nptr;
2386 } else {
2387 ptr->_next = nptr;
2388 }
2389 }
2390
2391 void Method::print_touched_methods(outputStream* out) {
2392 MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2393 out->print_cr("# Method::print_touched_methods version 1");
2394 if (_touched_method_table) {
2395 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2396 TouchedMethodRecord* ptr = _touched_method_table[i];
2397 while(ptr) {
2398 ptr->_class_name->print_symbol_on(out); out->print(".");
2399 ptr->_method_name->print_symbol_on(out); out->print(":");
2400 ptr->_method_signature->print_symbol_on(out); out->cr();
2401 ptr = ptr->_next;
2402 }
2403 }
2404 }
2405 }
2406
2407 // Verification
2408
2409 void Method::verify_on(outputStream* st) {
2410 guarantee(is_method(), "object must be method");
2411 guarantee(constants()->is_constantPool(), "should be constant pool");
2412 guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2413 MethodData* md = method_data();
2414 guarantee(md == NULL ||
2415 md->is_methodData(), "should be method data");
2416 }