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 "memory/universe.hpp"
45#include "oops/constMethod.hpp"
46#include "oops/constantPool.hpp"
47#include "oops/method.inline.hpp"
48#include "oops/methodData.hpp"
49#include "oops/objArrayKlass.hpp"
50#include "oops/objArrayOop.inline.hpp"
51#include "oops/oop.inline.hpp"
52#include "oops/symbol.hpp"
53#include "prims/jvmtiExport.hpp"
54#include "prims/methodHandles.hpp"
55#include "prims/nativeLookup.hpp"
56#include "runtime/arguments.hpp"
57#include "runtime/compilationPolicy.hpp"
58#include "runtime/frame.inline.hpp"
59#include "runtime/handles.inline.hpp"
60#include "runtime/init.hpp"
61#include "runtime/orderAccess.hpp"
62#include "runtime/relocator.hpp"
63#include "runtime/safepointVerifiers.hpp"
64#include "runtime/sharedRuntime.hpp"
65#include "runtime/signature.hpp"
66#include "utilities/align.hpp"
67#include "utilities/quickSort.hpp"
68#include "utilities/vmError.hpp"
69#include "utilities/xmlstream.hpp"
70
71// Implementation of Method
72
73Method* Method::allocate(ClassLoaderData* loader_data,
74 int byte_code_size,
75 AccessFlags access_flags,
76 InlineTableSizes* sizes,
77 ConstMethod::MethodType method_type,
78 TRAPS) {
79 assert(!access_flags.is_native() || byte_code_size == 0,
80 "native methods should not contain byte codes");
81 ConstMethod* cm = ConstMethod::allocate(loader_data,
82 byte_code_size,
83 sizes,
84 method_type,
85 CHECK_NULL);
86 int size = Method::size(access_flags.is_native());
87 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
88}
89
90Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
91 NoSafepointVerifier no_safepoint;
92 set_constMethod(xconst);
93 set_access_flags(access_flags);
94 set_intrinsic_id(vmIntrinsics::_none);
95 set_force_inline(false);
96 set_hidden(false);
97 set_dont_inline(false);
98 set_has_injected_profile(false);
99 set_method_data(NULL);
100 clear_method_counters();
101 set_vtable_index(Method::garbage_vtable_index);
102
103 // Fix and bury in Method*
104 set_interpreter_entry(NULL); // sets i2i entry and from_int
105 set_adapter_entry(NULL);
106 clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i
107
108 if (access_flags.is_native()) {
109 clear_native_function();
110 set_signature_handler(NULL);
111 }
112
113 NOT_PRODUCT(set_compiled_invocation_count(0);)
114}
115
116// Release Method*. The nmethod will be gone when we get here because
117// we've walked the code cache.
118void Method::deallocate_contents(ClassLoaderData* loader_data) {
119 MetadataFactory::free_metadata(loader_data, constMethod());
120 set_constMethod(NULL);
121#if INCLUDE_JVMCI
122 if (method_data()) {
123 FailedSpeculation::free_failed_speculations(method_data()->get_failed_speculations_address());
124 }
125#endif
126 MetadataFactory::free_metadata(loader_data, method_data());
127 set_method_data(NULL);
128 MetadataFactory::free_metadata(loader_data, method_counters());
129 clear_method_counters();
130 // The nmethod will be gone when we get here.
131 if (code() != NULL) _code = NULL;
132}
133
134address Method::get_i2c_entry() {
135 assert(adapter() != NULL, "must have");
136 return adapter()->get_i2c_entry();
137}
138
139address Method::get_c2i_entry() {
140 assert(adapter() != NULL, "must have");
141 return adapter()->get_c2i_entry();
142}
143
144address Method::get_c2i_unverified_entry() {
145 assert(adapter() != NULL, "must have");
146 return adapter()->get_c2i_unverified_entry();
147}
148
149char* Method::name_and_sig_as_C_string() const {
150 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
151}
152
153char* Method::name_and_sig_as_C_string(char* buf, int size) const {
154 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
155}
156
157char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
158 const char* klass_name = klass->external_name();
159 int klass_name_len = (int)strlen(klass_name);
160 int method_name_len = method_name->utf8_length();
161 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
162 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
163 strcpy(dest, klass_name);
164 dest[klass_name_len] = '.';
165 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
166 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
167 dest[len] = 0;
168 return dest;
169}
170
171char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
172 Symbol* klass_name = klass->name();
173 klass_name->as_klass_external_name(buf, size);
174 int len = (int)strlen(buf);
175
176 if (len < size - 1) {
177 buf[len++] = '.';
178
179 method_name->as_C_string(&(buf[len]), size - len);
180 len = (int)strlen(buf);
181
182 signature->as_C_string(&(buf[len]), size - len);
183 }
184
185 return buf;
186}
187
188const char* Method::external_name() const {
189 return external_name(constants()->pool_holder(), name(), signature());
190}
191
192void Method::print_external_name(outputStream *os) const {
193 print_external_name(os, constants()->pool_holder(), name(), signature());
194}
195
196const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
197 stringStream ss;
198 print_external_name(&ss, klass, method_name, signature);
199 return ss.as_string();
200}
201
202void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
203 signature->print_as_signature_external_return_type(os);
204 os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
205 signature->print_as_signature_external_parameters(os);
206 os->print(")");
207}
208
209int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
210 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
211 // access exception table
212 ExceptionTable table(mh());
213 int length = table.length();
214 // iterate through all entries sequentially
215 constantPoolHandle pool(THREAD, mh->constants());
216 for (int i = 0; i < length; i ++) {
217 //reacquire the table in case a GC happened
218 ExceptionTable table(mh());
219 int beg_bci = table.start_pc(i);
220 int end_bci = table.end_pc(i);
221 assert(beg_bci <= end_bci, "inconsistent exception table");
222 if (beg_bci <= throw_bci && throw_bci < end_bci) {
223 // exception handler bci range covers throw_bci => investigate further
224 int handler_bci = table.handler_pc(i);
225 int klass_index = table.catch_type_index(i);
226 if (klass_index == 0) {
227 return handler_bci;
228 } else if (ex_klass == NULL) {
229 return handler_bci;
230 } else {
231 // we know the exception class => get the constraint class
232 // this may require loading of the constraint class; if verification
233 // fails or some other exception occurs, return handler_bci
234 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
235 assert(k != NULL, "klass not loaded");
236 if (ex_klass->is_subtype_of(k)) {
237 return handler_bci;
238 }
239 }
240 }
241 }
242
243 return -1;
244}
245
246void Method::mask_for(int bci, InterpreterOopMap* mask) {
247 methodHandle h_this(Thread::current(), this);
248 // Only GC uses the OopMapCache during thread stack root scanning
249 // any other uses generate an oopmap but do not save it in the cache.
250 if (Universe::heap()->is_gc_active()) {
251 method_holder()->mask_for(h_this, bci, mask);
252 } else {
253 OopMapCache::compute_one_oop_map(h_this, bci, mask);
254 }
255 return;
256}
257
258
259int Method::bci_from(address bcp) const {
260 if (is_native() && bcp == 0) {
261 return 0;
262 }
263#ifdef ASSERT
264 {
265 ResourceMark rm;
266 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
267 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
268 p2i(bcp), name_and_sig_as_C_string());
269 }
270#endif
271 return bcp - code_base();
272}
273
274
275int Method::validate_bci(int bci) const {
276 return (bci == 0 || bci < code_size()) ? bci : -1;
277}
278
279// Return bci if it appears to be a valid bcp
280// Return -1 otherwise.
281// Used by profiling code, when invalid data is a possibility.
282// The caller is responsible for validating the Method* itself.
283int Method::validate_bci_from_bcp(address bcp) const {
284 // keep bci as -1 if not a valid bci
285 int bci = -1;
286 if (bcp == 0 || bcp == code_base()) {
287 // code_size() may return 0 and we allow 0 here
288 // the method may be native
289 bci = 0;
290 } else if (contains(bcp)) {
291 bci = bcp - code_base();
292 }
293 // Assert that if we have dodged any asserts, bci is negative.
294 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
295 return bci;
296}
297
298address Method::bcp_from(int bci) const {
299 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
300 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
301 address bcp = code_base() + bci;
302 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
303 return bcp;
304}
305
306address Method::bcp_from(address bcp) const {
307 if (is_native() && bcp == NULL) {
308 return code_base();
309 } else {
310 return bcp;
311 }
312}
313
314int Method::size(bool is_native) {
315 // If native, then include pointers for native_function and signature_handler
316 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
317 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
318 return align_metadata_size(header_size() + extra_words);
319}
320
321
322Symbol* Method::klass_name() const {
323 return method_holder()->name();
324}
325
326
327void Method::metaspace_pointers_do(MetaspaceClosure* it) {
328 log_trace(cds)("Iter(Method): %p", this);
329
330 it->push(&_constMethod);
331 it->push(&_method_data);
332 it->push(&_method_counters);
333}
334
335// Attempt to return method oop to original state. Clear any pointers
336// (to objects outside the shared spaces). We won't be able to predict
337// where they should point in a new JVM. Further initialize some
338// entries now in order allow them to be write protected later.
339
340void Method::remove_unshareable_info() {
341 unlink_method();
342}
343
344void Method::set_vtable_index(int index) {
345 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
346 // At runtime initialize_vtable is rerun as part of link_class_impl()
347 // for a shared class loaded by the non-boot loader to obtain the loader
348 // constraints based on the runtime classloaders' context.
349 return; // don't write into the shared class
350 } else {
351 _vtable_index = index;
352 }
353}
354
355void Method::set_itable_index(int index) {
356 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
357 // At runtime initialize_itable is rerun as part of link_class_impl()
358 // for a shared class loaded by the non-boot loader to obtain the loader
359 // constraints based on the runtime classloaders' context. The dumptime
360 // itable index should be the same as the runtime index.
361 assert(_vtable_index == itable_index_max - index,
362 "archived itable index is different from runtime index");
363 return; // don’t write into the shared class
364 } else {
365 _vtable_index = itable_index_max - index;
366 }
367 assert(valid_itable_index(), "");
368}
369
370
371
372bool Method::was_executed_more_than(int n) {
373 // Invocation counter is reset when the Method* is compiled.
374 // If the method has compiled code we therefore assume it has
375 // be excuted more than n times.
376 if (is_accessor() || is_empty_method() || (code() != NULL)) {
377 // interpreter doesn't bump invocation counter of trivial methods
378 // compiler does not bump invocation counter of compiled methods
379 return true;
380 }
381 else if ((method_counters() != NULL &&
382 method_counters()->invocation_counter()->carry()) ||
383 (method_data() != NULL &&
384 method_data()->invocation_counter()->carry())) {
385 // The carry bit is set when the counter overflows and causes
386 // a compilation to occur. We don't know how many times
387 // the counter has been reset, so we simply assume it has
388 // been executed more than n times.
389 return true;
390 } else {
391 return invocation_count() > n;
392 }
393}
394
395void Method::print_invocation_count() {
396 if (is_static()) tty->print("static ");
397 if (is_final()) tty->print("final ");
398 if (is_synchronized()) tty->print("synchronized ");
399 if (is_native()) tty->print("native ");
400 tty->print("%s::", method_holder()->external_name());
401 name()->print_symbol_on(tty);
402 signature()->print_symbol_on(tty);
403
404 if (WizardMode) {
405 // dump the size of the byte codes
406 tty->print(" {%d}", code_size());
407 }
408 tty->cr();
409
410 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count());
411 tty->print_cr (" invocation_counter: %8d ", invocation_count());
412 tty->print_cr (" backedge_counter: %8d ", backedge_count());
413#ifndef PRODUCT
414 if (CountCompiledCalls) {
415 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count());
416 }
417#endif
418}
419
420// Build a MethodData* object to hold information about this method
421// collected in the interpreter.
422void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
423 // Do not profile the method if metaspace has hit an OOM previously
424 // allocating profiling data. Callers clear pending exception so don't
425 // add one here.
426 if (ClassLoaderDataGraph::has_metaspace_oom()) {
427 return;
428 }
429
430 // Grab a lock here to prevent multiple
431 // MethodData*s from being created.
432 MutexLocker ml(MethodData_lock, THREAD);
433 if (method->method_data() == NULL) {
434 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
435 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
436 if (HAS_PENDING_EXCEPTION) {
437 CompileBroker::log_metaspace_failure();
438 ClassLoaderDataGraph::set_metaspace_oom(true);
439 return; // return the exception (which is cleared)
440 }
441
442 method->set_method_data(method_data);
443 if (PrintMethodData && (Verbose || WizardMode)) {
444 ResourceMark rm(THREAD);
445 tty->print("build_interpreter_method_data for ");
446 method->print_name(tty);
447 tty->cr();
448 // At the end of the run, the MDO, full of data, will be dumped.
449 }
450 }
451}
452
453MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
454 // Do not profile the method if metaspace has hit an OOM previously
455 if (ClassLoaderDataGraph::has_metaspace_oom()) {
456 return NULL;
457 }
458
459 methodHandle mh(m);
460 MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
461 if (HAS_PENDING_EXCEPTION) {
462 CompileBroker::log_metaspace_failure();
463 ClassLoaderDataGraph::set_metaspace_oom(true);
464 return NULL; // return the exception (which is cleared)
465 }
466 if (!mh->init_method_counters(counters)) {
467 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
468 }
469
470 if (LogTouchedMethods) {
471 mh->log_touched(CHECK_NULL);
472 }
473
474 return mh->method_counters();
475}
476
477bool Method::init_method_counters(MethodCounters* counters) {
478 // Try to install a pointer to MethodCounters, return true on success.
479 return Atomic::replace_if_null(counters, &_method_counters);
480}
481
482int Method::extra_stack_words() {
483 // not an inline function, to avoid a header dependency on Interpreter
484 return extra_stack_entries() * Interpreter::stackElementSize;
485}
486
487
488void Method::compute_size_of_parameters(Thread *thread) {
489 ArgumentSizeComputer asc(signature());
490 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
491}
492
493BasicType Method::result_type() const {
494 ResultTypeFinder rtf(signature());
495 return rtf.type();
496}
497
498
499bool Method::is_empty_method() const {
500 return code_size() == 1
501 && *code_base() == Bytecodes::_return;
502}
503
504
505bool Method::is_vanilla_constructor() const {
506 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
507 // which only calls the superclass vanilla constructor and possibly does stores of
508 // zero constants to local fields:
509 //
510 // aload_0
511 // invokespecial
512 // indexbyte1
513 // indexbyte2
514 //
515 // followed by an (optional) sequence of:
516 //
517 // aload_0
518 // aconst_null / iconst_0 / fconst_0 / dconst_0
519 // putfield
520 // indexbyte1
521 // indexbyte2
522 //
523 // followed by:
524 //
525 // return
526
527 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
528 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
529 int size = code_size();
530 // Check if size match
531 if (size == 0 || size % 5 != 0) return false;
532 address cb = code_base();
533 int last = size - 1;
534 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
535 // Does not call superclass default constructor
536 return false;
537 }
538 // Check optional sequence
539 for (int i = 4; i < last; i += 5) {
540 if (cb[i] != Bytecodes::_aload_0) return false;
541 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
542 if (cb[i+2] != Bytecodes::_putfield) return false;
543 }
544 return true;
545}
546
547
548bool Method::compute_has_loops_flag() {
549 BytecodeStream bcs(this);
550 Bytecodes::Code bc;
551
552 while ((bc = bcs.next()) >= 0) {
553 switch( bc ) {
554 case Bytecodes::_ifeq:
555 case Bytecodes::_ifnull:
556 case Bytecodes::_iflt:
557 case Bytecodes::_ifle:
558 case Bytecodes::_ifne:
559 case Bytecodes::_ifnonnull:
560 case Bytecodes::_ifgt:
561 case Bytecodes::_ifge:
562 case Bytecodes::_if_icmpeq:
563 case Bytecodes::_if_icmpne:
564 case Bytecodes::_if_icmplt:
565 case Bytecodes::_if_icmpgt:
566 case Bytecodes::_if_icmple:
567 case Bytecodes::_if_icmpge:
568 case Bytecodes::_if_acmpeq:
569 case Bytecodes::_if_acmpne:
570 case Bytecodes::_goto:
571 case Bytecodes::_jsr:
572 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
573 break;
574
575 case Bytecodes::_goto_w:
576 case Bytecodes::_jsr_w:
577 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
578 break;
579
580 default:
581 break;
582 }
583 }
584 _access_flags.set_loops_flag_init();
585 return _access_flags.has_loops();
586}
587
588bool Method::is_final_method(AccessFlags class_access_flags) const {
589 // or "does_not_require_vtable_entry"
590 // default method or overpass can occur, is not final (reuses vtable entry)
591 // private methods in classes get vtable entries for backward class compatibility.
592 if (is_overpass() || is_default_method()) return false;
593 return is_final() || class_access_flags.is_final();
594}
595
596bool Method::is_final_method() const {
597 return is_final_method(method_holder()->access_flags());
598}
599
600bool Method::is_default_method() const {
601 if (method_holder() != NULL &&
602 method_holder()->is_interface() &&
603 !is_abstract() && !is_private()) {
604 return true;
605 } else {
606 return false;
607 }
608}
609
610bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
611 if (is_final_method(class_access_flags)) return true;
612#ifdef ASSERT
613 ResourceMark rm;
614 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
615 if (class_access_flags.is_interface()) {
616 assert(is_nonv == is_static() || is_nonv == is_private(),
617 "nonvirtual unexpected for non-static, non-private: %s",
618 name_and_sig_as_C_string());
619 }
620#endif
621 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
622 return vtable_index() == nonvirtual_vtable_index;
623}
624
625bool Method::can_be_statically_bound() const {
626 return can_be_statically_bound(method_holder()->access_flags());
627}
628
629bool Method::can_be_statically_bound(InstanceKlass* context) const {
630 return (method_holder() == context) && can_be_statically_bound();
631}
632
633bool Method::is_accessor() const {
634 return is_getter() || is_setter();
635}
636
637bool Method::is_getter() const {
638 if (code_size() != 5) return false;
639 if (size_of_parameters() != 1) return false;
640 if (java_code_at(0) != Bytecodes::_aload_0) return false;
641 if (java_code_at(1) != Bytecodes::_getfield) return false;
642 switch (java_code_at(4)) {
643 case Bytecodes::_ireturn:
644 case Bytecodes::_lreturn:
645 case Bytecodes::_freturn:
646 case Bytecodes::_dreturn:
647 case Bytecodes::_areturn:
648 break;
649 default:
650 return false;
651 }
652 return true;
653}
654
655bool Method::is_setter() const {
656 if (code_size() != 6) return false;
657 if (java_code_at(0) != Bytecodes::_aload_0) return false;
658 switch (java_code_at(1)) {
659 case Bytecodes::_iload_1:
660 case Bytecodes::_aload_1:
661 case Bytecodes::_fload_1:
662 if (size_of_parameters() != 2) return false;
663 break;
664 case Bytecodes::_dload_1:
665 case Bytecodes::_lload_1:
666 if (size_of_parameters() != 3) return false;
667 break;
668 default:
669 return false;
670 }
671 if (java_code_at(2) != Bytecodes::_putfield) return false;
672 if (java_code_at(5) != Bytecodes::_return) return false;
673 return true;
674}
675
676bool Method::is_constant_getter() const {
677 int last_index = code_size() - 1;
678 // Check if the first 1-3 bytecodes are a constant push
679 // and the last bytecode is a return.
680 return (2 <= code_size() && code_size() <= 4 &&
681 Bytecodes::is_const(java_code_at(0)) &&
682 Bytecodes::length_for(java_code_at(0)) == last_index &&
683 Bytecodes::is_return(java_code_at(last_index)));
684}
685
686bool Method::is_initializer() const {
687 return is_object_initializer() || is_static_initializer();
688}
689
690bool Method::has_valid_initializer_flags() const {
691 return (is_static() ||
692 method_holder()->major_version() < 51);
693}
694
695bool Method::is_static_initializer() const {
696 // For classfiles version 51 or greater, ensure that the clinit method is
697 // static. Non-static methods with the name "<clinit>" are not static
698 // initializers. (older classfiles exempted for backward compatibility)
699 return name() == vmSymbols::class_initializer_name() &&
700 has_valid_initializer_flags();
701}
702
703bool Method::is_object_initializer() const {
704 return name() == vmSymbols::object_initializer_name();
705}
706
707bool Method::needs_clinit_barrier() const {
708 return is_static() && !method_holder()->is_initialized();
709}
710
711objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
712 int length = method->checked_exceptions_length();
713 if (length == 0) { // common case
714 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
715 } else {
716 methodHandle h_this(THREAD, method);
717 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
718 objArrayHandle mirrors (THREAD, m_oop);
719 for (int i = 0; i < length; i++) {
720 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
721 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
722 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
723 mirrors->obj_at_put(i, k->java_mirror());
724 }
725 return mirrors;
726 }
727};
728
729
730int Method::line_number_from_bci(int bci) const {
731 int best_bci = 0;
732 int best_line = -1;
733 if (bci == SynchronizationEntryBCI) bci = 0;
734 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
735 // The line numbers are a short array of 2-tuples [start_pc, line_number].
736 // Not necessarily sorted and not necessarily one-to-one.
737 CompressedLineNumberReadStream stream(compressed_linenumber_table());
738 while (stream.read_pair()) {
739 if (stream.bci() == bci) {
740 // perfect match
741 return stream.line();
742 } else {
743 // update best_bci/line
744 if (stream.bci() < bci && stream.bci() >= best_bci) {
745 best_bci = stream.bci();
746 best_line = stream.line();
747 }
748 }
749 }
750 }
751 return best_line;
752}
753
754
755bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
756 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
757 Thread *thread = Thread::current();
758 Symbol* klass_name = constants()->klass_name_at(klass_index);
759 Handle loader(thread, method_holder()->class_loader());
760 Handle prot (thread, method_holder()->protection_domain());
761 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
762 } else {
763 return true;
764 }
765}
766
767
768bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
769 int klass_index = constants()->klass_ref_index_at(refinfo_index);
770 if (must_be_resolved) {
771 // Make sure klass is resolved in constantpool.
772 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
773 }
774 return is_klass_loaded_by_klass_index(klass_index);
775}
776
777
778void Method::set_native_function(address function, bool post_event_flag) {
779 assert(function != NULL, "use clear_native_function to unregister natives");
780 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
781 address* native_function = native_function_addr();
782
783 // We can see racers trying to place the same native function into place. Once
784 // is plenty.
785 address current = *native_function;
786 if (current == function) return;
787 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
788 function != NULL) {
789 // native_method_throw_unsatisfied_link_error_entry() should only
790 // be passed when post_event_flag is false.
791 assert(function !=
792 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
793 "post_event_flag mis-match");
794
795 // post the bind event, and possible change the bind function
796 JvmtiExport::post_native_method_bind(this, &function);
797 }
798 *native_function = function;
799 // This function can be called more than once. We must make sure that we always
800 // use the latest registered method -> check if a stub already has been generated.
801 // If so, we have to make it not_entrant.
802 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
803 if (nm != NULL) {
804 nm->make_not_entrant();
805 }
806}
807
808
809bool Method::has_native_function() const {
810 if (is_method_handle_intrinsic())
811 return false; // special-cased in SharedRuntime::generate_native_wrapper
812 address func = native_function();
813 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
814}
815
816
817void Method::clear_native_function() {
818 // Note: is_method_handle_intrinsic() is allowed here.
819 set_native_function(
820 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
821 !native_bind_event_is_interesting);
822 clear_code();
823}
824
825address Method::critical_native_function() {
826 methodHandle mh(this);
827 return NativeLookup::lookup_critical_entry(mh);
828}
829
830
831void Method::set_signature_handler(address handler) {
832 address* signature_handler = signature_handler_addr();
833 *signature_handler = handler;
834}
835
836
837void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
838 assert(reason != NULL, "must provide a reason");
839 if (PrintCompilation && report) {
840 ttyLocker ttyl;
841 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
842 if (comp_level == CompLevel_all) {
843 tty->print("all levels ");
844 } else {
845 tty->print("levels ");
846 for (int i = (int)CompLevel_none; i <= comp_level; i++) {
847 tty->print("%d ", i);
848 }
849 }
850 this->print_short_name(tty);
851 int size = this->code_size();
852 if (size > 0) {
853 tty->print(" (%d bytes)", size);
854 }
855 if (reason != NULL) {
856 tty->print(" %s", reason);
857 }
858 tty->cr();
859 }
860 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
861 ttyLocker ttyl;
862 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
863 os::current_thread_id(), is_osr, comp_level);
864 if (reason != NULL) {
865 xtty->print(" reason=\'%s\'", reason);
866 }
867 xtty->method(this);
868 xtty->stamp();
869 xtty->end_elem();
870 }
871}
872
873bool Method::is_always_compilable() const {
874 // Generated adapters must be compiled
875 if (is_method_handle_intrinsic() && is_synthetic()) {
876 assert(!is_not_c1_compilable(), "sanity check");
877 assert(!is_not_c2_compilable(), "sanity check");
878 return true;
879 }
880
881 return false;
882}
883
884bool Method::is_not_compilable(int comp_level) const {
885 if (number_of_breakpoints() > 0)
886 return true;
887 if (is_always_compilable())
888 return false;
889 if (comp_level == CompLevel_any)
890 return is_not_c1_compilable() || is_not_c2_compilable();
891 if (is_c1_compile(comp_level))
892 return is_not_c1_compilable();
893 if (is_c2_compile(comp_level))
894 return is_not_c2_compilable();
895 return false;
896}
897
898// call this when compiler finds that this method is not compilable
899void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
900 if (is_always_compilable()) {
901 // Don't mark a method which should be always compilable
902 return;
903 }
904 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
905 if (comp_level == CompLevel_all) {
906 set_not_c1_compilable();
907 set_not_c2_compilable();
908 } else {
909 if (is_c1_compile(comp_level))
910 set_not_c1_compilable();
911 if (is_c2_compile(comp_level))
912 set_not_c2_compilable();
913 }
914 CompilationPolicy::policy()->disable_compilation(this);
915 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
916}
917
918bool Method::is_not_osr_compilable(int comp_level) const {
919 if (is_not_compilable(comp_level))
920 return true;
921 if (comp_level == CompLevel_any)
922 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
923 if (is_c1_compile(comp_level))
924 return is_not_c1_osr_compilable();
925 if (is_c2_compile(comp_level))
926 return is_not_c2_osr_compilable();
927 return false;
928}
929
930void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
931 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
932 if (comp_level == CompLevel_all) {
933 set_not_c1_osr_compilable();
934 set_not_c2_osr_compilable();
935 } else {
936 if (is_c1_compile(comp_level))
937 set_not_c1_osr_compilable();
938 if (is_c2_compile(comp_level))
939 set_not_c2_osr_compilable();
940 }
941 CompilationPolicy::policy()->disable_compilation(this);
942 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
943}
944
945// Revert to using the interpreter and clear out the nmethod
946void Method::clear_code(bool acquire_lock /* = true */) {
947 MutexLocker pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
948 // this may be NULL if c2i adapters have not been made yet
949 // Only should happen at allocate time.
950 if (adapter() == NULL) {
951 _from_compiled_entry = NULL;
952 } else {
953 _from_compiled_entry = adapter()->get_c2i_entry();
954 }
955 OrderAccess::storestore();
956 _from_interpreted_entry = _i2i_entry;
957 OrderAccess::storestore();
958 _code = NULL;
959}
960
961#if INCLUDE_CDS
962// Called by class data sharing to remove any entry points (which are not shared)
963void Method::unlink_method() {
964 _code = NULL;
965
966 assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "dump time only");
967 // Set the values to what they should be at run time. Note that
968 // this Method can no longer be executed during dump time.
969 _i2i_entry = Interpreter::entry_for_cds_method(this);
970 _from_interpreted_entry = _i2i_entry;
971
972 if (DynamicDumpSharedSpaces) {
973 assert(_from_compiled_entry != NULL, "sanity");
974 } else {
975 // TODO: Simplify the adapter trampoline allocation for static archiving.
976 // Remove the use of CDSAdapterHandlerEntry.
977 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
978 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
979 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
980 assert(*((int*)_from_compiled_entry) == 0,
981 "must be NULL during dump time, to be initialized at run time");
982 }
983
984 if (is_native()) {
985 *native_function_addr() = NULL;
986 set_signature_handler(NULL);
987 }
988 NOT_PRODUCT(set_compiled_invocation_count(0);)
989
990 set_method_data(NULL);
991 clear_method_counters();
992}
993#endif
994
995/****************************************************************************
996// The following illustrates how the entries work for CDS shared Methods:
997//
998// Our goal is to delay writing into a shared Method until it's compiled.
999// Hence, we want to determine the initial values for _i2i_entry,
1000// _from_interpreted_entry and _from_compiled_entry during CDS dump time.
1001//
1002// In this example, both Methods A and B have the _i2i_entry of "zero_locals".
1003// They also have similar signatures so that they will share the same
1004// AdapterHandlerEntry.
1005//
1006// _adapter_trampoline points to a fixed location in the RW section of
1007// the CDS archive. This location initially contains a NULL pointer. When the
1008// first of method A or B is linked, an AdapterHandlerEntry is allocated
1009// dynamically, and its c2i/i2c entries are generated.
1010//
1011// _i2i_entry and _from_interpreted_entry initially points to the same
1012// (fixed) location in the CODE section of the CDS archive. This contains
1013// an unconditional branch to the actual entry for "zero_locals", which is
1014// generated at run time and may be on an arbitrary address. Thus, the
1015// unconditional branch is also generated at run time to jump to the correct
1016// address.
1017//
1018// Similarly, _from_compiled_entry points to a fixed address in the CODE
1019// section. This address has enough space for an unconditional branch
1020// instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1021// initialized, and the address for the actual c2i_entry is known, we emit a
1022// branch instruction here to branch to the actual c2i_entry.
1023//
1024// The effect of the extra branch on the i2i and c2i entries is negligible.
1025//
1026// The reason for putting _adapter_trampoline in RO is many shared Methods
1027// share the same AdapterHandlerEntry, so we can save space in the RW section
1028// by having the extra indirection.
1029
1030
1031[Method A: RW]
1032 _constMethod ----> [ConstMethod: RO]
1033 _adapter_trampoline -----------+
1034 |
1035 _i2i_entry (same value as method B) |
1036 _from_interpreted_entry (same value as method B) |
1037 _from_compiled_entry (same value as method B) |
1038 |
1039 |
1040[Method B: RW] +--------+
1041 _constMethod ----> [ConstMethod: RO] |
1042 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1043 |
1044 +-------------------------------+
1045 |
1046 +----> [AdapterHandlerEntry] (allocated at run time)
1047 _fingerprint
1048 _c2i_entry ---------------------------------+->[c2i entry..]
1049 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1050 _from_interpreted_entry | _c2i_unverified_entry | |
1051 | | | |
1052 | | (_cds_entry_table: CODE) | |
1053 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1054 | | (allocated at run time) | |
1055 | | ... [asm code ...] | |
1056 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1057 | | |
1058 | | |
1059 +-[compiled]-------------------------------------------------------------------+ |
1060 |
1061 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1062 [jmp c2i_entry] ------------------------------------------------------+
1063
1064***/
1065
1066// Called when the method_holder is getting linked. Setup entrypoints so the method
1067// is ready to be called from interpreter, compiler, and vtables.
1068void Method::link_method(const methodHandle& h_method, TRAPS) {
1069 // If the code cache is full, we may reenter this function for the
1070 // leftover methods that weren't linked.
1071 if (is_shared()) {
1072 address entry = Interpreter::entry_for_cds_method(h_method);
1073 assert(entry != NULL && entry == _i2i_entry,
1074 "should be correctly set during dump time");
1075 if (adapter() != NULL) {
1076 return;
1077 }
1078 assert(entry == _from_interpreted_entry,
1079 "should be correctly set during dump time");
1080 } else if (_i2i_entry != NULL) {
1081 return;
1082 }
1083 assert( _code == NULL, "nothing compiled yet" );
1084
1085 // Setup interpreter entrypoint
1086 assert(this == h_method(), "wrong h_method()" );
1087
1088 if (!is_shared()) {
1089 assert(adapter() == NULL, "init'd to NULL");
1090 address entry = Interpreter::entry_for_method(h_method);
1091 assert(entry != NULL, "interpreter entry must be non-null");
1092 // Sets both _i2i_entry and _from_interpreted_entry
1093 set_interpreter_entry(entry);
1094 }
1095
1096 // Don't overwrite already registered native entries.
1097 if (is_native() && !has_native_function()) {
1098 set_native_function(
1099 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1100 !native_bind_event_is_interesting);
1101 }
1102
1103 // Setup compiler entrypoint. This is made eagerly, so we do not need
1104 // special handling of vtables. An alternative is to make adapters more
1105 // lazily by calling make_adapter() from from_compiled_entry() for the
1106 // normal calls. For vtable calls life gets more complicated. When a
1107 // call-site goes mega-morphic we need adapters in all methods which can be
1108 // called from the vtable. We need adapters on such methods that get loaded
1109 // later. Ditto for mega-morphic itable calls. If this proves to be a
1110 // problem we'll make these lazily later.
1111 (void) make_adapters(h_method, CHECK);
1112
1113 // ONLY USE the h_method now as make_adapter may have blocked
1114
1115}
1116
1117address Method::make_adapters(const methodHandle& mh, TRAPS) {
1118 // Adapters for compiled code are made eagerly here. They are fairly
1119 // small (generally < 100 bytes) and quick to make (and cached and shared)
1120 // so making them eagerly shouldn't be too expensive.
1121 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1122 if (adapter == NULL ) {
1123 if (!is_init_completed()) {
1124 // Don't throw exceptions during VM initialization because java.lang.* classes
1125 // might not have been initialized, causing problems when constructing the
1126 // Java exception object.
1127 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1128 } else {
1129 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1130 }
1131 }
1132
1133 if (mh->is_shared()) {
1134 assert(mh->adapter() == adapter, "must be");
1135 assert(mh->_from_compiled_entry != NULL, "must be");
1136 } else {
1137 mh->set_adapter_entry(adapter);
1138 mh->_from_compiled_entry = adapter->get_c2i_entry();
1139 }
1140 return adapter->get_c2i_entry();
1141}
1142
1143void Method::restore_unshareable_info(TRAPS) {
1144 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1145
1146 // Since restore_unshareable_info can be called more than once for a method, don't
1147 // redo any work.
1148 if (adapter() == NULL) {
1149 methodHandle mh(THREAD, this);
1150 link_method(mh, CHECK);
1151 }
1152}
1153
1154address Method::from_compiled_entry_no_trampoline() const {
1155 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1156 if (code) {
1157 return code->verified_entry_point();
1158 } else {
1159 return adapter()->get_c2i_entry();
1160 }
1161}
1162
1163// The verified_code_entry() must be called when a invoke is resolved
1164// on this method.
1165
1166// It returns the compiled code entry point, after asserting not null.
1167// This function is called after potential safepoints so that nmethod
1168// or adapter that it points to is still live and valid.
1169// This function must not hit a safepoint!
1170address Method::verified_code_entry() {
1171 debug_only(NoSafepointVerifier nsv;)
1172 assert(_from_compiled_entry != NULL, "must be set");
1173 return _from_compiled_entry;
1174}
1175
1176// Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1177// (could be racing a deopt).
1178// Not inline to avoid circular ref.
1179bool Method::check_code() const {
1180 // cached in a register or local. There's a race on the value of the field.
1181 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1182 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1183}
1184
1185// Install compiled code. Instantly it can execute.
1186void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1187 MutexLocker pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1188 assert( code, "use clear_code to remove code" );
1189 assert( mh->check_code(), "" );
1190
1191 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1192
1193 // These writes must happen in this order, because the interpreter will
1194 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1195 // which jumps to _from_compiled_entry.
1196 mh->_code = code; // Assign before allowing compiled code to exec
1197
1198 int comp_level = code->comp_level();
1199 // In theory there could be a race here. In practice it is unlikely
1200 // and not worth worrying about.
1201 if (comp_level > mh->highest_comp_level()) {
1202 mh->set_highest_comp_level(comp_level);
1203 }
1204
1205 OrderAccess::storestore();
1206 mh->_from_compiled_entry = code->verified_entry_point();
1207 OrderAccess::storestore();
1208 // Instantly compiled code can execute.
1209 if (!mh->is_method_handle_intrinsic())
1210 mh->_from_interpreted_entry = mh->get_i2c_entry();
1211}
1212
1213
1214bool Method::is_overridden_in(Klass* k) const {
1215 InstanceKlass* ik = InstanceKlass::cast(k);
1216
1217 if (ik->is_interface()) return false;
1218
1219 // If method is an interface, we skip it - except if it
1220 // is a miranda method
1221 if (method_holder()->is_interface()) {
1222 // Check that method is not a miranda method
1223 if (ik->lookup_method(name(), signature()) == NULL) {
1224 // No implementation exist - so miranda method
1225 return false;
1226 }
1227 return true;
1228 }
1229
1230 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1231 if (!has_vtable_index()) {
1232 return false;
1233 } else {
1234 Method* vt_m = ik->method_at_vtable(vtable_index());
1235 return vt_m != this;
1236 }
1237}
1238
1239
1240// give advice about whether this Method* should be cached or not
1241bool Method::should_not_be_cached() const {
1242 if (is_old()) {
1243 // This method has been redefined. It is either EMCP or obsolete
1244 // and we don't want to cache it because that would pin the method
1245 // down and prevent it from being collectible if and when it
1246 // finishes executing.
1247 return true;
1248 }
1249
1250 // caching this method should be just fine
1251 return false;
1252}
1253
1254
1255/**
1256 * Returns true if this is one of the specially treated methods for
1257 * security related stack walks (like Reflection.getCallerClass).
1258 */
1259bool Method::is_ignored_by_security_stack_walk() const {
1260 if (intrinsic_id() == vmIntrinsics::_invoke) {
1261 // This is Method.invoke() -- ignore it
1262 return true;
1263 }
1264 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1265 // This is an auxilary frame -- ignore it
1266 return true;
1267 }
1268 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1269 // This is an internal adapter frame for method handles -- ignore it
1270 return true;
1271 }
1272 return false;
1273}
1274
1275
1276// Constant pool structure for invoke methods:
1277enum {
1278 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1279 _imcp_invoke_signature, // utf8: (variable Symbol*)
1280 _imcp_limit
1281};
1282
1283// Test if this method is an MH adapter frame generated by Java code.
1284// Cf. java/lang/invoke/InvokerBytecodeGenerator
1285bool Method::is_compiled_lambda_form() const {
1286 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1287}
1288
1289// Test if this method is an internal MH primitive method.
1290bool Method::is_method_handle_intrinsic() const {
1291 vmIntrinsics::ID iid = intrinsic_id();
1292 return (MethodHandles::is_signature_polymorphic(iid) &&
1293 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1294}
1295
1296bool Method::has_member_arg() const {
1297 vmIntrinsics::ID iid = intrinsic_id();
1298 return (MethodHandles::is_signature_polymorphic(iid) &&
1299 MethodHandles::has_member_arg(iid));
1300}
1301
1302// Make an instance of a signature-polymorphic internal MH primitive.
1303methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1304 Symbol* signature,
1305 TRAPS) {
1306 ResourceMark rm;
1307 methodHandle empty;
1308
1309 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1310 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1311 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1312 if (TraceMethodHandles) {
1313 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1314 }
1315
1316 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1317 name->increment_refcount();
1318 signature->increment_refcount();
1319
1320 int cp_length = _imcp_limit;
1321 ClassLoaderData* loader_data = holder->class_loader_data();
1322 constantPoolHandle cp;
1323 {
1324 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1325 cp = constantPoolHandle(THREAD, cp_oop);
1326 }
1327 cp->set_pool_holder(holder);
1328 cp->symbol_at_put(_imcp_invoke_name, name);
1329 cp->symbol_at_put(_imcp_invoke_signature, signature);
1330 cp->set_has_preresolution();
1331
1332 // decide on access bits: public or not?
1333 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1334 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1335 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1336 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1337
1338 methodHandle m;
1339 {
1340 InlineTableSizes sizes;
1341 Method* m_oop = Method::allocate(loader_data, 0,
1342 accessFlags_from(flags_bits), &sizes,
1343 ConstMethod::NORMAL, CHECK_(empty));
1344 m = methodHandle(THREAD, m_oop);
1345 }
1346 m->set_constants(cp());
1347 m->set_name_index(_imcp_invoke_name);
1348 m->set_signature_index(_imcp_invoke_signature);
1349 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1350 assert(m->signature() == signature, "");
1351 ResultTypeFinder rtf(signature);
1352 m->constMethod()->set_result_type(rtf.type());
1353 m->compute_size_of_parameters(THREAD);
1354 m->init_intrinsic_id();
1355 assert(m->is_method_handle_intrinsic(), "");
1356#ifdef ASSERT
1357 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1358 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1359 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1360#endif //ASSERT
1361
1362 // Finally, set up its entry points.
1363 assert(m->can_be_statically_bound(), "");
1364 m->set_vtable_index(Method::nonvirtual_vtable_index);
1365 m->link_method(m, CHECK_(empty));
1366
1367 if (TraceMethodHandles && (Verbose || WizardMode)) {
1368 ttyLocker ttyl;
1369 m->print_on(tty);
1370 }
1371
1372 return m;
1373}
1374
1375Klass* Method::check_non_bcp_klass(Klass* klass) {
1376 if (klass != NULL && klass->class_loader() != NULL) {
1377 if (klass->is_objArray_klass())
1378 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1379 return klass;
1380 }
1381 return NULL;
1382}
1383
1384
1385methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1386 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1387 // Code below does not work for native methods - they should never get rewritten anyway
1388 assert(!m->is_native(), "cannot rewrite native methods");
1389 // Allocate new Method*
1390 AccessFlags flags = m->access_flags();
1391
1392 ConstMethod* cm = m->constMethod();
1393 int checked_exceptions_len = cm->checked_exceptions_length();
1394 int localvariable_len = cm->localvariable_table_length();
1395 int exception_table_len = cm->exception_table_length();
1396 int method_parameters_len = cm->method_parameters_length();
1397 int method_annotations_len = cm->method_annotations_length();
1398 int parameter_annotations_len = cm->parameter_annotations_length();
1399 int type_annotations_len = cm->type_annotations_length();
1400 int default_annotations_len = cm->default_annotations_length();
1401
1402 InlineTableSizes sizes(
1403 localvariable_len,
1404 new_compressed_linenumber_size,
1405 exception_table_len,
1406 checked_exceptions_len,
1407 method_parameters_len,
1408 cm->generic_signature_index(),
1409 method_annotations_len,
1410 parameter_annotations_len,
1411 type_annotations_len,
1412 default_annotations_len,
1413 0);
1414
1415 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1416 Method* newm_oop = Method::allocate(loader_data,
1417 new_code_length,
1418 flags,
1419 &sizes,
1420 m->method_type(),
1421 CHECK_(methodHandle()));
1422 methodHandle newm (THREAD, newm_oop);
1423
1424 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1425 ConstMethod* newcm = newm->constMethod();
1426 int new_const_method_size = newm->constMethod()->size();
1427
1428 // This works because the source and target are both Methods. Some compilers
1429 // (e.g., clang) complain that the target vtable pointer will be stomped,
1430 // so cast away newm()'s and m()'s Methodness.
1431 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1432
1433 // Create shallow copy of ConstMethod.
1434 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1435
1436 // Reset correct method/const method, method size, and parameter info
1437 newm->set_constMethod(newcm);
1438 newm->constMethod()->set_code_size(new_code_length);
1439 newm->constMethod()->set_constMethod_size(new_const_method_size);
1440 assert(newm->code_size() == new_code_length, "check");
1441 assert(newm->method_parameters_length() == method_parameters_len, "check");
1442 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1443 assert(newm->exception_table_length() == exception_table_len, "check");
1444 assert(newm->localvariable_table_length() == localvariable_len, "check");
1445 // Copy new byte codes
1446 memcpy(newm->code_base(), new_code, new_code_length);
1447 // Copy line number table
1448 if (new_compressed_linenumber_size > 0) {
1449 memcpy(newm->compressed_linenumber_table(),
1450 new_compressed_linenumber_table,
1451 new_compressed_linenumber_size);
1452 }
1453 // Copy method_parameters
1454 if (method_parameters_len > 0) {
1455 memcpy(newm->method_parameters_start(),
1456 m->method_parameters_start(),
1457 method_parameters_len * sizeof(MethodParametersElement));
1458 }
1459 // Copy checked_exceptions
1460 if (checked_exceptions_len > 0) {
1461 memcpy(newm->checked_exceptions_start(),
1462 m->checked_exceptions_start(),
1463 checked_exceptions_len * sizeof(CheckedExceptionElement));
1464 }
1465 // Copy exception table
1466 if (exception_table_len > 0) {
1467 memcpy(newm->exception_table_start(),
1468 m->exception_table_start(),
1469 exception_table_len * sizeof(ExceptionTableElement));
1470 }
1471 // Copy local variable number table
1472 if (localvariable_len > 0) {
1473 memcpy(newm->localvariable_table_start(),
1474 m->localvariable_table_start(),
1475 localvariable_len * sizeof(LocalVariableTableElement));
1476 }
1477 // Copy stackmap table
1478 if (m->has_stackmap_table()) {
1479 int code_attribute_length = m->stackmap_data()->length();
1480 Array<u1>* stackmap_data =
1481 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1482 memcpy((void*)stackmap_data->adr_at(0),
1483 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1484 newm->set_stackmap_data(stackmap_data);
1485 }
1486
1487 // copy annotations over to new method
1488 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1489 return newm;
1490}
1491
1492vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1493 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1494 // because we are not loading from core libraries
1495 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1496 // which does not use the class default class loader so we check for its loader here
1497 const InstanceKlass* ik = InstanceKlass::cast(holder);
1498 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1499 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1500 }
1501
1502 // see if the klass name is well-known:
1503 Symbol* klass_name = ik->name();
1504 return vmSymbols::find_sid(klass_name);
1505}
1506
1507void Method::init_intrinsic_id() {
1508 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1509 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1510 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1511 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1512
1513 // the klass name is well-known:
1514 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1515 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1516
1517 // ditto for method and signature:
1518 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1519 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1520 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1521 && name_id == vmSymbols::NO_SID) {
1522 return;
1523 }
1524 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1525 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1526 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1527 && sig_id == vmSymbols::NO_SID) {
1528 return;
1529 }
1530 jshort flags = access_flags().as_short();
1531
1532 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1533 if (id != vmIntrinsics::_none) {
1534 set_intrinsic_id(id);
1535 if (id == vmIntrinsics::_Class_cast) {
1536 // Even if the intrinsic is rejected, we want to inline this simple method.
1537 set_force_inline(true);
1538 }
1539 return;
1540 }
1541
1542 // A few slightly irregular cases:
1543 switch (klass_id) {
1544 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1545 // Second chance: check in regular Math.
1546 switch (name_id) {
1547 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1548 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1549 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1550 // pretend it is the corresponding method in the non-strict class:
1551 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1552 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1553 break;
1554 default:
1555 break;
1556 }
1557 break;
1558
1559 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1560 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1561 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1562 if (!is_native()) break;
1563 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1564 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1565 id = vmIntrinsics::_none;
1566 break;
1567
1568 default:
1569 break;
1570 }
1571
1572 if (id != vmIntrinsics::_none) {
1573 // Set up its iid. It is an alias method.
1574 set_intrinsic_id(id);
1575 return;
1576 }
1577}
1578
1579// These two methods are static since a GC may move the Method
1580bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1581 if (!THREAD->can_call_java()) {
1582 // There is nothing useful this routine can do from within the Compile thread.
1583 // Hopefully, the signature contains only well-known classes.
1584 // We could scan for this and return true/false, but the caller won't care.
1585 return false;
1586 }
1587 bool sig_is_loaded = true;
1588 Handle class_loader(THREAD, m->method_holder()->class_loader());
1589 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1590 ResourceMark rm(THREAD);
1591 Symbol* signature = m->signature();
1592 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1593 if (ss.is_object()) {
1594 Symbol* sym = ss.as_symbol();
1595 Symbol* name = sym;
1596 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1597 protection_domain, THREAD);
1598 // We are loading classes eagerly. If a ClassNotFoundException or
1599 // a LinkageError was generated, be sure to ignore it.
1600 if (HAS_PENDING_EXCEPTION) {
1601 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1602 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1603 CLEAR_PENDING_EXCEPTION;
1604 } else {
1605 return false;
1606 }
1607 }
1608 if( klass == NULL) { sig_is_loaded = false; }
1609 }
1610 }
1611 return sig_is_loaded;
1612}
1613
1614bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1615 Handle class_loader(THREAD, m->method_holder()->class_loader());
1616 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1617 ResourceMark rm(THREAD);
1618 Symbol* signature = m->signature();
1619 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1620 if (ss.type() == T_OBJECT) {
1621 Symbol* name = ss.as_symbol_or_null();
1622 if (name == NULL) return true;
1623 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1624 if (klass == NULL) return true;
1625 }
1626 }
1627 return false;
1628}
1629
1630// Exposed so field engineers can debug VM
1631void Method::print_short_name(outputStream* st) {
1632 ResourceMark rm;
1633#ifdef PRODUCT
1634 st->print(" %s::", method_holder()->external_name());
1635#else
1636 st->print(" %s::", method_holder()->internal_name());
1637#endif
1638 name()->print_symbol_on(st);
1639 if (WizardMode) signature()->print_symbol_on(st);
1640 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1641 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1642}
1643
1644// Comparer for sorting an object array containing
1645// Method*s.
1646static int method_comparator(Method* a, Method* b) {
1647 return a->name()->fast_compare(b->name());
1648}
1649
1650// This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1651// default_methods also uses this without the ordering for fast find_method
1652void Method::sort_methods(Array<Method*>* methods, bool set_idnums) {
1653 int length = methods->length();
1654 if (length > 1) {
1655 {
1656 NoSafepointVerifier nsv;
1657 QuickSort::sort(methods->data(), length, method_comparator, /*idempotent=*/false);
1658 }
1659 // Reset method ordering
1660 if (set_idnums) {
1661 for (int i = 0; i < length; i++) {
1662 Method* m = methods->at(i);
1663 m->set_method_idnum(i);
1664 m->set_orig_method_idnum(i);
1665 }
1666 }
1667 }
1668}
1669
1670//-----------------------------------------------------------------------------------
1671// Non-product code unless JVM/TI needs it
1672
1673#if !defined(PRODUCT) || INCLUDE_JVMTI
1674class SignatureTypePrinter : public SignatureTypeNames {
1675 private:
1676 outputStream* _st;
1677 bool _use_separator;
1678
1679 void type_name(const char* name) {
1680 if (_use_separator) _st->print(", ");
1681 _st->print("%s", name);
1682 _use_separator = true;
1683 }
1684
1685 public:
1686 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1687 _st = st;
1688 _use_separator = false;
1689 }
1690
1691 void print_parameters() { _use_separator = false; iterate_parameters(); }
1692 void print_returntype() { _use_separator = false; iterate_returntype(); }
1693};
1694
1695
1696void Method::print_name(outputStream* st) {
1697 Thread *thread = Thread::current();
1698 ResourceMark rm(thread);
1699 st->print("%s ", is_static() ? "static" : "virtual");
1700 if (WizardMode) {
1701 st->print("%s.", method_holder()->internal_name());
1702 name()->print_symbol_on(st);
1703 signature()->print_symbol_on(st);
1704 } else {
1705 SignatureTypePrinter sig(signature(), st);
1706 sig.print_returntype();
1707 st->print(" %s.", method_holder()->internal_name());
1708 name()->print_symbol_on(st);
1709 st->print("(");
1710 sig.print_parameters();
1711 st->print(")");
1712 }
1713}
1714#endif // !PRODUCT || INCLUDE_JVMTI
1715
1716
1717void Method::print_codes_on(outputStream* st) const {
1718 print_codes_on(0, code_size(), st);
1719}
1720
1721void Method::print_codes_on(int from, int to, outputStream* st) const {
1722 Thread *thread = Thread::current();
1723 ResourceMark rm(thread);
1724 methodHandle mh (thread, (Method*)this);
1725 BytecodeStream s(mh);
1726 s.set_interval(from, to);
1727 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1728 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1729}
1730
1731CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1732 _bci = 0;
1733 _line = 0;
1734};
1735
1736bool CompressedLineNumberReadStream::read_pair() {
1737 jubyte next = read_byte();
1738 // Check for terminator
1739 if (next == 0) return false;
1740 if (next == 0xFF) {
1741 // Escape character, regular compression used
1742 _bci += read_signed_int();
1743 _line += read_signed_int();
1744 } else {
1745 // Single byte compression used
1746 _bci += next >> 3;
1747 _line += next & 0x7;
1748 }
1749 return true;
1750}
1751
1752#if INCLUDE_JVMTI
1753
1754Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1755 BreakpointInfo* bp = method_holder()->breakpoints();
1756 for (; bp != NULL; bp = bp->next()) {
1757 if (bp->match(this, bci)) {
1758 return bp->orig_bytecode();
1759 }
1760 }
1761 {
1762 ResourceMark rm;
1763 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1764 }
1765 return Bytecodes::_shouldnotreachhere;
1766}
1767
1768void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1769 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1770 BreakpointInfo* bp = method_holder()->breakpoints();
1771 for (; bp != NULL; bp = bp->next()) {
1772 if (bp->match(this, bci)) {
1773 bp->set_orig_bytecode(code);
1774 // and continue, in case there is more than one
1775 }
1776 }
1777}
1778
1779void Method::set_breakpoint(int bci) {
1780 InstanceKlass* ik = method_holder();
1781 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1782 bp->set_next(ik->breakpoints());
1783 ik->set_breakpoints(bp);
1784 // do this last:
1785 bp->set(this);
1786}
1787
1788static void clear_matches(Method* m, int bci) {
1789 InstanceKlass* ik = m->method_holder();
1790 BreakpointInfo* prev_bp = NULL;
1791 BreakpointInfo* next_bp;
1792 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1793 next_bp = bp->next();
1794 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1795 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1796 // do this first:
1797 bp->clear(m);
1798 // unhook it
1799 if (prev_bp != NULL)
1800 prev_bp->set_next(next_bp);
1801 else
1802 ik->set_breakpoints(next_bp);
1803 delete bp;
1804 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1805 // at same location. So we have multiple matching (method_index and bci)
1806 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1807 // breakpoint for clear_breakpoint request and keep all other method versions
1808 // BreakpointInfo for future clear_breakpoint request.
1809 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1810 // which is being called when class is unloaded. We delete all the Breakpoint
1811 // information for all versions of method. We may not correctly restore the original
1812 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1813 // so these methods won't be used anymore.
1814 if (bci >= 0) {
1815 break;
1816 }
1817 } else {
1818 // This one is a keeper.
1819 prev_bp = bp;
1820 }
1821 }
1822}
1823
1824void Method::clear_breakpoint(int bci) {
1825 assert(bci >= 0, "");
1826 clear_matches(this, bci);
1827}
1828
1829void Method::clear_all_breakpoints() {
1830 clear_matches(this, -1);
1831}
1832
1833#endif // INCLUDE_JVMTI
1834
1835int Method::invocation_count() {
1836 MethodCounters *mcs = method_counters();
1837 if (TieredCompilation) {
1838 MethodData* const mdo = method_data();
1839 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1840 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1841 return InvocationCounter::count_limit;
1842 } else {
1843 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1844 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1845 }
1846 } else {
1847 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1848 }
1849}
1850
1851int Method::backedge_count() {
1852 MethodCounters *mcs = method_counters();
1853 if (TieredCompilation) {
1854 MethodData* const mdo = method_data();
1855 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1856 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1857 return InvocationCounter::count_limit;
1858 } else {
1859 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1860 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1861 }
1862 } else {
1863 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1864 }
1865}
1866
1867int Method::highest_comp_level() const {
1868 const MethodCounters* mcs = method_counters();
1869 if (mcs != NULL) {
1870 return mcs->highest_comp_level();
1871 } else {
1872 return CompLevel_none;
1873 }
1874}
1875
1876int Method::highest_osr_comp_level() const {
1877 const MethodCounters* mcs = method_counters();
1878 if (mcs != NULL) {
1879 return mcs->highest_osr_comp_level();
1880 } else {
1881 return CompLevel_none;
1882 }
1883}
1884
1885void Method::set_highest_comp_level(int level) {
1886 MethodCounters* mcs = method_counters();
1887 if (mcs != NULL) {
1888 mcs->set_highest_comp_level(level);
1889 }
1890}
1891
1892void Method::set_highest_osr_comp_level(int level) {
1893 MethodCounters* mcs = method_counters();
1894 if (mcs != NULL) {
1895 mcs->set_highest_osr_comp_level(level);
1896 }
1897}
1898
1899#if INCLUDE_JVMTI
1900
1901BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1902 _bci = bci;
1903 _name_index = m->name_index();
1904 _signature_index = m->signature_index();
1905 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1906 if (_orig_bytecode == Bytecodes::_breakpoint)
1907 _orig_bytecode = m->orig_bytecode_at(_bci);
1908 _next = NULL;
1909}
1910
1911void BreakpointInfo::set(Method* method) {
1912#ifdef ASSERT
1913 {
1914 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1915 if (code == Bytecodes::_breakpoint)
1916 code = method->orig_bytecode_at(_bci);
1917 assert(orig_bytecode() == code, "original bytecode must be the same");
1918 }
1919#endif
1920 Thread *thread = Thread::current();
1921 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1922 method->incr_number_of_breakpoints(thread);
1923 SystemDictionary::notice_modification();
1924 {
1925 // Deoptimize all dependents on this method
1926 HandleMark hm(thread);
1927 methodHandle mh(thread, method);
1928 CodeCache::flush_dependents_on_method(mh);
1929 }
1930}
1931
1932void BreakpointInfo::clear(Method* method) {
1933 *method->bcp_from(_bci) = orig_bytecode();
1934 assert(method->number_of_breakpoints() > 0, "must not go negative");
1935 method->decr_number_of_breakpoints(Thread::current());
1936}
1937
1938#endif // INCLUDE_JVMTI
1939
1940// jmethodID handling
1941
1942// This is a block allocating object, sort of like JNIHandleBlock, only a
1943// lot simpler.
1944// It's allocated on the CHeap because once we allocate a jmethodID, we can
1945// never get rid of it.
1946
1947static const int min_block_size = 8;
1948
1949class JNIMethodBlockNode : public CHeapObj<mtClass> {
1950 friend class JNIMethodBlock;
1951 Method** _methods;
1952 int _number_of_methods;
1953 int _top;
1954 JNIMethodBlockNode* _next;
1955
1956 public:
1957
1958 JNIMethodBlockNode(int num_methods = min_block_size);
1959
1960 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1961
1962 void ensure_methods(int num_addl_methods) {
1963 if (_top < _number_of_methods) {
1964 num_addl_methods -= _number_of_methods - _top;
1965 if (num_addl_methods <= 0) {
1966 return;
1967 }
1968 }
1969 if (_next == NULL) {
1970 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1971 } else {
1972 _next->ensure_methods(num_addl_methods);
1973 }
1974 }
1975};
1976
1977class JNIMethodBlock : public CHeapObj<mtClass> {
1978 JNIMethodBlockNode _head;
1979 JNIMethodBlockNode *_last_free;
1980 public:
1981 static Method* const _free_method;
1982
1983 JNIMethodBlock(int initial_capacity = min_block_size)
1984 : _head(initial_capacity), _last_free(&_head) {}
1985
1986 void ensure_methods(int num_addl_methods) {
1987 _last_free->ensure_methods(num_addl_methods);
1988 }
1989
1990 Method** add_method(Method* m) {
1991 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1992 if (b->_top < b->_number_of_methods) {
1993 // top points to the next free entry.
1994 int i = b->_top;
1995 b->_methods[i] = m;
1996 b->_top++;
1997 _last_free = b;
1998 return &(b->_methods[i]);
1999 } else if (b->_top == b->_number_of_methods) {
2000 // if the next free entry ran off the block see if there's a free entry
2001 for (int i = 0; i < b->_number_of_methods; i++) {
2002 if (b->_methods[i] == _free_method) {
2003 b->_methods[i] = m;
2004 _last_free = b;
2005 return &(b->_methods[i]);
2006 }
2007 }
2008 // Only check each block once for frees. They're very unlikely.
2009 // Increment top past the end of the block.
2010 b->_top++;
2011 }
2012 // need to allocate a next block.
2013 if (b->_next == NULL) {
2014 b->_next = _last_free = new JNIMethodBlockNode();
2015 }
2016 }
2017 guarantee(false, "Should always allocate a free block");
2018 return NULL;
2019 }
2020
2021 bool contains(Method** m) {
2022 if (m == NULL) return false;
2023 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2024 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2025 // This is a bit of extra checking, for two reasons. One is
2026 // that contains() deals with pointers that are passed in by
2027 // JNI code, so making sure that the pointer is aligned
2028 // correctly is valuable. The other is that <= and > are
2029 // technically not defined on pointers, so the if guard can
2030 // pass spuriously; no modern compiler is likely to make that
2031 // a problem, though (and if one did, the guard could also
2032 // fail spuriously, which would be bad).
2033 ptrdiff_t idx = m - b->_methods;
2034 if (b->_methods + idx == m) {
2035 return true;
2036 }
2037 }
2038 }
2039 return false; // not found
2040 }
2041
2042 // Doesn't really destroy it, just marks it as free so it can be reused.
2043 void destroy_method(Method** m) {
2044#ifdef ASSERT
2045 assert(contains(m), "should be a methodID");
2046#endif // ASSERT
2047 *m = _free_method;
2048 }
2049
2050 // During class unloading the methods are cleared, which is different
2051 // than freed.
2052 void clear_all_methods() {
2053 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2054 for (int i = 0; i< b->_number_of_methods; i++) {
2055 b->_methods[i] = NULL;
2056 }
2057 }
2058 }
2059#ifndef PRODUCT
2060 int count_methods() {
2061 // count all allocated methods
2062 int count = 0;
2063 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2064 for (int i = 0; i< b->_number_of_methods; i++) {
2065 if (b->_methods[i] != _free_method) count++;
2066 }
2067 }
2068 return count;
2069 }
2070#endif // PRODUCT
2071};
2072
2073// Something that can't be mistaken for an address or a markOop
2074Method* const JNIMethodBlock::_free_method = (Method*)55;
2075
2076JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2077 _number_of_methods = MAX2(num_methods, min_block_size);
2078 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2079 for (int i = 0; i < _number_of_methods; i++) {
2080 _methods[i] = JNIMethodBlock::_free_method;
2081 }
2082}
2083
2084void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2085 ClassLoaderData* cld = loader_data;
2086 if (!SafepointSynchronize::is_at_safepoint()) {
2087 // Have to add jmethod_ids() to class loader data thread-safely.
2088 // Also have to add the method to the list safely, which the cld lock
2089 // protects as well.
2090 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2091 if (cld->jmethod_ids() == NULL) {
2092 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2093 } else {
2094 cld->jmethod_ids()->ensure_methods(capacity);
2095 }
2096 } else {
2097 // At safepoint, we are single threaded and can set this.
2098 if (cld->jmethod_ids() == NULL) {
2099 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2100 } else {
2101 cld->jmethod_ids()->ensure_methods(capacity);
2102 }
2103 }
2104}
2105
2106// Add a method id to the jmethod_ids
2107jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2108 ClassLoaderData* cld = loader_data;
2109
2110 if (!SafepointSynchronize::is_at_safepoint()) {
2111 // Have to add jmethod_ids() to class loader data thread-safely.
2112 // Also have to add the method to the list safely, which the cld lock
2113 // protects as well.
2114 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2115 if (cld->jmethod_ids() == NULL) {
2116 cld->set_jmethod_ids(new JNIMethodBlock());
2117 }
2118 // jmethodID is a pointer to Method*
2119 return (jmethodID)cld->jmethod_ids()->add_method(m);
2120 } else {
2121 // At safepoint, we are single threaded and can set this.
2122 if (cld->jmethod_ids() == NULL) {
2123 cld->set_jmethod_ids(new JNIMethodBlock());
2124 }
2125 // jmethodID is a pointer to Method*
2126 return (jmethodID)cld->jmethod_ids()->add_method(m);
2127 }
2128}
2129
2130// Mark a jmethodID as free. This is called when there is a data race in
2131// InstanceKlass while creating the jmethodID cache.
2132void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2133 ClassLoaderData* cld = loader_data;
2134 Method** ptr = (Method**)m;
2135 assert(cld->jmethod_ids() != NULL, "should have method handles");
2136 cld->jmethod_ids()->destroy_method(ptr);
2137}
2138
2139void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2140 // Can't assert the method_holder is the same because the new method has the
2141 // scratch method holder.
2142 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2143 == new_method->method_holder()->class_loader() ||
2144 new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2145 "changing to a different class loader");
2146 // Just change the method in place, jmethodID pointer doesn't change.
2147 *((Method**)jmid) = new_method;
2148}
2149
2150bool Method::is_method_id(jmethodID mid) {
2151 Method* m = resolve_jmethod_id(mid);
2152 assert(m != NULL, "should be called with non-null method");
2153 InstanceKlass* ik = m->method_holder();
2154 ClassLoaderData* cld = ik->class_loader_data();
2155 if (cld->jmethod_ids() == NULL) return false;
2156 return (cld->jmethod_ids()->contains((Method**)mid));
2157}
2158
2159Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2160 if (mid == NULL) return NULL;
2161 Method* o = resolve_jmethod_id(mid);
2162 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2163 return NULL;
2164 }
2165 return o;
2166};
2167
2168void Method::set_on_stack(const bool value) {
2169 // Set both the method itself and its constant pool. The constant pool
2170 // on stack means some method referring to it is also on the stack.
2171 constants()->set_on_stack(value);
2172
2173 bool already_set = on_stack();
2174 _access_flags.set_on_stack(value);
2175 if (value && !already_set) {
2176 MetadataOnStackMark::record(this);
2177 }
2178 assert(!value || !is_old() || is_obsolete() || is_running_emcp(),
2179 "emcp methods cannot run after emcp bit is cleared");
2180}
2181
2182// Called when the class loader is unloaded to make all methods weak.
2183void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2184 loader_data->jmethod_ids()->clear_all_methods();
2185}
2186
2187bool Method::has_method_vptr(const void* ptr) {
2188 Method m;
2189 // This assumes that the vtbl pointer is the first word of a C++ object.
2190 return dereference_vptr(&m) == dereference_vptr(ptr);
2191}
2192
2193// Check that this pointer is valid by checking that the vtbl pointer matches
2194bool Method::is_valid_method(const Method* m) {
2195 if (m == NULL) {
2196 return false;
2197 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2198 // Quick sanity check on pointer.
2199 return false;
2200 } else if (m->is_shared()) {
2201 return MetaspaceShared::is_valid_shared_method(m);
2202 } else if (Metaspace::contains_non_shared(m)) {
2203 return has_method_vptr((const void*)m);
2204 } else {
2205 return false;
2206 }
2207}
2208
2209#ifndef PRODUCT
2210void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2211 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2212}
2213#endif // PRODUCT
2214
2215
2216// Printing
2217
2218#ifndef PRODUCT
2219
2220void Method::print_on(outputStream* st) const {
2221 ResourceMark rm;
2222 assert(is_method(), "must be method");
2223 st->print_cr("%s", internal_name());
2224 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2225 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2226 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2227 constants()->print_value_on(st); st->cr();
2228 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2229 st->print (" - name: "); name()->print_value_on(st); st->cr();
2230 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2231 st->print_cr(" - max stack: %d", max_stack());
2232 st->print_cr(" - max locals: %d", max_locals());
2233 st->print_cr(" - size of params: %d", size_of_parameters());
2234 st->print_cr(" - method size: %d", method_size());
2235 if (intrinsic_id() != vmIntrinsics::_none)
2236 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2237 if (highest_comp_level() != CompLevel_none)
2238 st->print_cr(" - highest level: %d", highest_comp_level());
2239 st->print_cr(" - vtable index: %d", _vtable_index);
2240 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2241 st->print( " - adapters: ");
2242 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2243 if (a == NULL)
2244 st->print_cr(INTPTR_FORMAT, p2i(a));
2245 else
2246 a->print_adapter_on(st);
2247 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2248 st->print_cr(" - code size: %d", code_size());
2249 if (code_size() != 0) {
2250 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2251 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2252 }
2253 if (method_data() != NULL) {
2254 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2255 }
2256 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2257 if (checked_exceptions_length() > 0) {
2258 CheckedExceptionElement* table = checked_exceptions_start();
2259 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2260 if (Verbose) {
2261 for (int i = 0; i < checked_exceptions_length(); i++) {
2262 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2263 }
2264 }
2265 }
2266 if (has_linenumber_table()) {
2267 u_char* table = compressed_linenumber_table();
2268 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2269 if (Verbose) {
2270 CompressedLineNumberReadStream stream(table);
2271 while (stream.read_pair()) {
2272 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2273 }
2274 }
2275 }
2276 st->print_cr(" - localvar length: %d", localvariable_table_length());
2277 if (localvariable_table_length() > 0) {
2278 LocalVariableTableElement* table = localvariable_table_start();
2279 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2280 if (Verbose) {
2281 for (int i = 0; i < localvariable_table_length(); i++) {
2282 int bci = table[i].start_bci;
2283 int len = table[i].length;
2284 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2285 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2286 int slot = table[i].slot;
2287 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2288 }
2289 }
2290 }
2291 if (code() != NULL) {
2292 st->print (" - compiled code: ");
2293 code()->print_value_on(st);
2294 }
2295 if (is_native()) {
2296 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2297 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2298 }
2299}
2300
2301void Method::print_linkage_flags(outputStream* st) {
2302 access_flags().print_on(st);
2303 if (is_default_method()) {
2304 st->print("default ");
2305 }
2306 if (is_overpass()) {
2307 st->print("overpass ");
2308 }
2309}
2310#endif //PRODUCT
2311
2312void Method::print_value_on(outputStream* st) const {
2313 assert(is_method(), "must be method");
2314 st->print("%s", internal_name());
2315 print_address_on(st);
2316 st->print(" ");
2317 name()->print_value_on(st);
2318 st->print(" ");
2319 signature()->print_value_on(st);
2320 st->print(" in ");
2321 method_holder()->print_value_on(st);
2322 if (WizardMode) st->print("#%d", _vtable_index);
2323 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2324 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2325}
2326
2327#if INCLUDE_SERVICES
2328// Size Statistics
2329void Method::collect_statistics(KlassSizeStats *sz) const {
2330 int mysize = sz->count(this);
2331 sz->_method_bytes += mysize;
2332 sz->_method_all_bytes += mysize;
2333 sz->_rw_bytes += mysize;
2334
2335 if (constMethod()) {
2336 constMethod()->collect_statistics(sz);
2337 }
2338 if (method_data()) {
2339 method_data()->collect_statistics(sz);
2340 }
2341}
2342#endif // INCLUDE_SERVICES
2343
2344// LogTouchedMethods and PrintTouchedMethods
2345
2346// TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2347// the Method may be garbage collected. Let's roll our own hash table.
2348class TouchedMethodRecord : CHeapObj<mtTracing> {
2349public:
2350 // It's OK to store Symbols here because they will NOT be GC'ed if
2351 // LogTouchedMethods is enabled.
2352 TouchedMethodRecord* _next;
2353 Symbol* _class_name;
2354 Symbol* _method_name;
2355 Symbol* _method_signature;
2356};
2357
2358static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2359static TouchedMethodRecord** _touched_method_table = NULL;
2360
2361void Method::log_touched(TRAPS) {
2362
2363 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2364 Symbol* my_class = klass_name();
2365 Symbol* my_name = name();
2366 Symbol* my_sig = signature();
2367
2368 unsigned int hash = my_class->identity_hash() +
2369 my_name->identity_hash() +
2370 my_sig->identity_hash();
2371 juint index = juint(hash) % table_size;
2372
2373 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2374 if (_touched_method_table == NULL) {
2375 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2376 mtTracing, CURRENT_PC);
2377 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2378 }
2379
2380 TouchedMethodRecord* ptr = _touched_method_table[index];
2381 while (ptr) {
2382 if (ptr->_class_name == my_class &&
2383 ptr->_method_name == my_name &&
2384 ptr->_method_signature == my_sig) {
2385 return;
2386 }
2387 if (ptr->_next == NULL) break;
2388 ptr = ptr->_next;
2389 }
2390 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2391 my_class->increment_refcount();
2392 my_name->increment_refcount();
2393 my_sig->increment_refcount();
2394 nptr->_class_name = my_class;
2395 nptr->_method_name = my_name;
2396 nptr->_method_signature = my_sig;
2397 nptr->_next = NULL;
2398
2399 if (ptr == NULL) {
2400 // first
2401 _touched_method_table[index] = nptr;
2402 } else {
2403 ptr->_next = nptr;
2404 }
2405}
2406
2407void Method::print_touched_methods(outputStream* out) {
2408 MutexLocker ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2409 out->print_cr("# Method::print_touched_methods version 1");
2410 if (_touched_method_table) {
2411 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2412 TouchedMethodRecord* ptr = _touched_method_table[i];
2413 while(ptr) {
2414 ptr->_class_name->print_symbol_on(out); out->print(".");
2415 ptr->_method_name->print_symbol_on(out); out->print(":");
2416 ptr->_method_signature->print_symbol_on(out); out->cr();
2417 ptr = ptr->_next;
2418 }
2419 }
2420 }
2421}
2422
2423// Verification
2424
2425void Method::verify_on(outputStream* st) {
2426 guarantee(is_method(), "object must be method");
2427 guarantee(constants()->is_constantPool(), "should be constant pool");
2428 MethodData* md = method_data();
2429 guarantee(md == NULL ||
2430 md->is_methodData(), "should be method data");
2431}
2432