1 /*
2 * Copyright (c) 1997, 2023, 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.
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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.
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23 */
24
25 #include "precompiled.hpp"
26 #include "code/codeBehaviours.hpp"
27 #include "code/codeCache.hpp"
28 #include "code/compiledIC.hpp"
29 #include "code/icBuffer.hpp"
30 #include "code/nmethod.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "interpreter/linkResolver.hpp"
34 #include "memory/metadataFactory.hpp"
35 #include "memory/oopFactory.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "memory/universe.hpp"
38 #include "oops/klass.inline.hpp"
39 #include "oops/method.inline.hpp"
40 #include "oops/oop.inline.hpp"
41 #include "oops/symbol.hpp"
42 #include "runtime/continuationEntry.hpp"
43 #include "runtime/handles.inline.hpp"
44 #include "runtime/icache.hpp"
45 #include "runtime/safepoint.hpp"
46 #include "runtime/sharedRuntime.hpp"
47 #include "runtime/stubRoutines.hpp"
48 #include "sanitizers/leak.hpp"
49 #include "utilities/events.hpp"
50
51
52 // Every time a compiled IC is changed or its type is being accessed,
53 // either the CompiledIC_lock must be set or we must be at a safe point.
54
55 CompiledICLocker::CompiledICLocker(CompiledMethod* method)
56 : _method(method),
57 _behaviour(CompiledICProtectionBehaviour::current()),
58 _locked(_behaviour->lock(_method)) {
59 }
60
61 CompiledICLocker::~CompiledICLocker() {
62 if (_locked) {
63 _behaviour->unlock(_method);
64 }
65 }
66
67 bool CompiledICLocker::is_safe(CompiledMethod* method) {
68 return CompiledICProtectionBehaviour::current()->is_safe(method);
69 }
70
71 bool CompiledICLocker::is_safe(address code) {
72 CodeBlob* cb = CodeCache::find_blob(code);
73 assert(cb != nullptr && cb->is_compiled(), "must be compiled");
74 CompiledMethod* cm = cb->as_compiled_method();
75 return CompiledICProtectionBehaviour::current()->is_safe(cm);
76 }
77
78 //-----------------------------------------------------------------------------
79 // Low-level access to an inline cache. Private, since they might not be
80 // MT-safe to use.
81
82 void* CompiledIC::cached_value() const {
83 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
84 assert (!is_optimized(), "an optimized virtual call does not have a cached metadata");
85
86 if (!is_in_transition_state()) {
87 void* data = get_data();
88 // If we let the metadata value here be initialized to zero...
89 assert(data != nullptr || Universe::non_oop_word() == nullptr,
90 "no raw nulls in CompiledIC metadatas, because of patching races");
91 return (data == (void*)Universe::non_oop_word()) ? nullptr : data;
92 } else {
93 return InlineCacheBuffer::cached_value_for((CompiledIC *)this);
94 }
95 }
96
97
98 void CompiledIC::internal_set_ic_destination(address entry_point, bool is_icstub, void* cache, bool is_icholder) {
99 assert(entry_point != nullptr, "must set legal entry point");
100 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
101 assert (!is_optimized() || cache == nullptr, "an optimized virtual call does not have a cached metadata");
102 assert (cache == nullptr || cache != (Metadata*)badOopVal, "invalid metadata");
103
104 assert(!is_icholder || is_icholder_entry(entry_point), "must be");
105
106 // Don't use ic_destination for this test since that forwards
107 // through ICBuffer instead of returning the actual current state of
108 // the CompiledIC.
109 if (is_icholder_entry(_call->destination())) {
110 // When patching for the ICStub case the cached value isn't
111 // overwritten until the ICStub copied into the CompiledIC during
112 // the next safepoint. Make sure that the CompiledICHolder* is
113 // marked for release at this point since it won't be identifiable
114 // once the entry point is overwritten.
115 InlineCacheBuffer::queue_for_release((CompiledICHolder*)get_data());
116 }
117
118 if (TraceCompiledIC) {
119 tty->print(" ");
120 print_compiled_ic();
121 tty->print(" changing destination to " INTPTR_FORMAT, p2i(entry_point));
122 if (!is_optimized()) {
123 tty->print(" changing cached %s to " INTPTR_FORMAT, is_icholder ? "icholder" : "metadata", p2i((address)cache));
124 }
125 if (is_icstub) {
126 tty->print(" (icstub)");
127 }
128 tty->cr();
129 }
130
131 {
132 CodeBlob* cb = CodeCache::find_blob(_call->instruction_address());
133 assert(cb != nullptr && cb->is_compiled(), "must be compiled");
134 _call->set_destination_mt_safe(entry_point);
135 }
136
137 if (is_optimized() || is_icstub) {
138 // Optimized call sites don't have a cache value and ICStub call
139 // sites only change the entry point. Changing the value in that
140 // case could lead to MT safety issues.
141 assert(cache == nullptr, "must be null");
142 return;
143 }
144
145 if (cache == nullptr) cache = Universe::non_oop_word();
146
147 set_data((intptr_t)cache);
148 }
149
150
151 void CompiledIC::set_ic_destination(ICStub* stub) {
152 internal_set_ic_destination(stub->code_begin(), true, nullptr, false);
153 }
154
155
156
157 address CompiledIC::ic_destination() const {
158 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
159 if (!is_in_transition_state()) {
160 return _call->destination();
161 } else {
162 return InlineCacheBuffer::ic_destination_for((CompiledIC *)this);
163 }
164 }
165
166
167 bool CompiledIC::is_in_transition_state() const {
168 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
169 return InlineCacheBuffer::contains(_call->destination());;
170 }
171
172
173 bool CompiledIC::is_icholder_call() const {
174 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
175 return !_is_optimized && is_icholder_entry(ic_destination());
176 }
177
178 // Returns native address of 'call' instruction in inline-cache. Used by
179 // the InlineCacheBuffer when it needs to find the stub.
180 address CompiledIC::stub_address() const {
181 assert(is_in_transition_state(), "should only be called when we are in a transition state");
182 return _call->destination();
183 }
184
185 // Clears the IC stub if the compiled IC is in transition state
186 void CompiledIC::clear_ic_stub() {
187 if (is_in_transition_state()) {
188 ICStub* stub = ICStub_from_destination_address(stub_address());
189 stub->clear();
190 }
191 }
192
193 //-----------------------------------------------------------------------------
194 // High-level access to an inline cache. Guaranteed to be MT-safe.
195
196 void CompiledIC::initialize_from_iter(RelocIterator* iter) {
197 assert(iter->addr() == _call->instruction_address(), "must find ic_call");
198
199 if (iter->type() == relocInfo::virtual_call_type) {
200 virtual_call_Relocation* r = iter->virtual_call_reloc();
201 _is_optimized = false;
202 _value = _call->get_load_instruction(r);
203 } else {
204 assert(iter->type() == relocInfo::opt_virtual_call_type, "must be a virtual call");
205 _is_optimized = true;
206 _value = nullptr;
207 }
208 }
209
210 CompiledIC::CompiledIC(CompiledMethod* cm, NativeCall* call)
211 : _method(cm)
212 {
213 _call = _method->call_wrapper_at((address) call);
214 address ic_call = _call->instruction_address();
215
216 assert(ic_call != nullptr, "ic_call address must be set");
217 assert(cm != nullptr, "must pass compiled method");
218 assert(cm->contains(ic_call), "must be in compiled method");
219
220 // Search for the ic_call at the given address.
221 RelocIterator iter(cm, ic_call, ic_call+1);
222 bool ret = iter.next();
223 assert(ret == true, "relocInfo must exist at this address");
224 assert(iter.addr() == ic_call, "must find ic_call");
225
226 initialize_from_iter(&iter);
227 }
228
229 CompiledIC::CompiledIC(RelocIterator* iter)
230 : _method(iter->code())
231 {
232 _call = _method->call_wrapper_at(iter->addr());
233 address ic_call = _call->instruction_address();
234
235 CompiledMethod* nm = iter->code();
236 assert(ic_call != nullptr, "ic_call address must be set");
237 assert(nm != nullptr, "must pass compiled method");
238 assert(nm->contains(ic_call), "must be in compiled method");
239
240 initialize_from_iter(iter);
241 }
242
243 // This function may fail for two reasons: either due to running out of vtable
244 // stubs, or due to running out of IC stubs in an attempted transition to a
245 // transitional state. The needs_ic_stub_refill value will be set if the failure
246 // was due to running out of IC stubs, in which case the caller will refill IC
247 // stubs and retry.
248 bool CompiledIC::set_to_megamorphic(CallInfo* call_info, Bytecodes::Code bytecode,
249 bool& needs_ic_stub_refill, TRAPS) {
250 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
251 assert(!is_optimized(), "cannot set an optimized virtual call to megamorphic");
252 assert(is_call_to_compiled() || is_call_to_interpreted(), "going directly to megamorphic?");
253
254 address entry;
255 if (call_info->call_kind() == CallInfo::itable_call) {
256 assert(bytecode == Bytecodes::_invokeinterface, "");
257 int itable_index = call_info->itable_index();
258 entry = VtableStubs::find_itable_stub(itable_index);
259 if (entry == nullptr) {
260 return false;
261 }
262 #ifdef ASSERT
263 int index = call_info->resolved_method()->itable_index();
264 assert(index == itable_index, "CallInfo pre-computes this");
265 InstanceKlass* k = call_info->resolved_method()->method_holder();
266 assert(k->verify_itable_index(itable_index), "sanity check");
267 #endif //ASSERT
268 CompiledICHolder* holder = new CompiledICHolder(call_info->resolved_method()->method_holder(),
269 call_info->resolved_klass(), false);
270 holder->claim();
271 if (!InlineCacheBuffer::create_transition_stub(this, holder, entry)) {
272 delete holder;
273 needs_ic_stub_refill = true;
274 return false;
275 }
276 // LSan appears unable to follow malloc-based memory consistently when embedded as an immediate
277 // in generated machine code. So we have to ignore it.
278 LSAN_IGNORE_OBJECT(holder);
279 } else {
280 assert(call_info->call_kind() == CallInfo::vtable_call, "either itable or vtable");
281 // Can be different than selected_method->vtable_index(), due to package-private etc.
282 int vtable_index = call_info->vtable_index();
283 assert(call_info->resolved_klass()->verify_vtable_index(vtable_index), "sanity check");
284 entry = VtableStubs::find_vtable_stub(vtable_index);
285 if (entry == nullptr) {
286 return false;
287 }
288 if (!InlineCacheBuffer::create_transition_stub(this, nullptr, entry)) {
289 needs_ic_stub_refill = true;
290 return false;
291 }
292 }
293
294 if (TraceICs) {
295 ResourceMark rm;
296 assert(call_info->selected_method() != nullptr, "Unexpected null selected method");
297 tty->print_cr ("IC@" INTPTR_FORMAT ": to megamorphic %s entry: " INTPTR_FORMAT,
298 p2i(instruction_address()), call_info->selected_method()->print_value_string(), p2i(entry));
299 }
300
301 // We can't check this anymore. With lazy deopt we could have already
302 // cleaned this IC entry before we even return. This is possible if
303 // we ran out of space in the inline cache buffer trying to do the
304 // set_next and we safepointed to free up space. This is a benign
305 // race because the IC entry was complete when we safepointed so
306 // cleaning it immediately is harmless.
307 // assert(is_megamorphic(), "sanity check");
308 return true;
309 }
310
311
312 // true if destination is megamorphic stub
313 bool CompiledIC::is_megamorphic() const {
314 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
315 assert(!is_optimized(), "an optimized call cannot be megamorphic");
316
317 // Cannot rely on cached_value. It is either an interface or a method.
318 return VtableStubs::entry_point(ic_destination()) != nullptr;
319 }
320
321 bool CompiledIC::is_call_to_compiled() const {
322 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
323
324 CodeBlob* cb = CodeCache::find_blob(ic_destination());
325 bool is_monomorphic = (cb != nullptr && cb->is_compiled());
326 // Check that the cached_value is a klass for non-optimized monomorphic calls
327 // This assertion is invalid for compiler1: a call that does not look optimized (no static stub) can be used
328 // for calling directly to vep without using the inline cache (i.e., cached_value == nullptr).
329 // For JVMCI this occurs because CHA is only used to improve inlining so call sites which could be optimized
330 // virtuals because there are no currently loaded subclasses of a type are left as virtual call sites.
331 #ifdef ASSERT
332 CodeBlob* caller = CodeCache::find_blob(instruction_address());
333 bool is_c1_or_jvmci_method = caller->is_compiled_by_c1() || caller->is_compiled_by_jvmci();
334 assert( is_c1_or_jvmci_method ||
335 !is_monomorphic ||
336 is_optimized() ||
337 (cached_metadata() != nullptr && cached_metadata()->is_klass()), "sanity check");
338 #endif // ASSERT
339 return is_monomorphic;
340 }
341
342
343 bool CompiledIC::is_call_to_interpreted() const {
344 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
345 // Call to interpreter if destination is either calling to a stub (if it
346 // is optimized), or calling to an I2C blob
347 bool is_call_to_interpreted = false;
348 if (!is_optimized()) {
349 CodeBlob* cb = CodeCache::find_blob(ic_destination());
350 is_call_to_interpreted = (cb != nullptr && cb->is_adapter_blob());
351 assert(!is_call_to_interpreted || (is_icholder_call() && cached_icholder() != nullptr), "sanity check");
352 } else {
353 // Check if we are calling into our own codeblob (i.e., to a stub)
354 address dest = ic_destination();
355 #ifdef ASSERT
356 {
357 _call->verify_resolve_call(dest);
358 }
359 #endif /* ASSERT */
360 is_call_to_interpreted = _call->is_call_to_interpreted(dest);
361 }
362 return is_call_to_interpreted;
363 }
364
365 bool CompiledIC::set_to_clean(bool in_use) {
366 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
367 if (TraceInlineCacheClearing || TraceICs) {
368 tty->print_cr("IC@" INTPTR_FORMAT ": set to clean", p2i(instruction_address()));
369 print();
370 }
371
372 address entry = _call->get_resolve_call_stub(is_optimized());
373
374 bool safe_transition = _call->is_safe_for_patching() || !in_use || is_optimized() || SafepointSynchronize::is_at_safepoint();
375
376 if (safe_transition) {
377 // Kill any leftover stub we might have too
378 clear_ic_stub();
379 if (is_optimized()) {
380 set_ic_destination(entry);
381 } else {
382 set_ic_destination_and_value(entry, (void*)nullptr);
383 }
384 } else {
385 // Unsafe transition - create stub.
386 if (!InlineCacheBuffer::create_transition_stub(this, nullptr, entry)) {
387 return false;
388 }
389 }
390 // We can't check this anymore. With lazy deopt we could have already
391 // cleaned this IC entry before we even return. This is possible if
392 // we ran out of space in the inline cache buffer trying to do the
393 // set_next and we safepointed to free up space. This is a benign
394 // race because the IC entry was complete when we safepointed so
395 // cleaning it immediately is harmless.
396 // assert(is_clean(), "sanity check");
397 return true;
398 }
399
400 bool CompiledIC::is_clean() const {
401 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
402 bool is_clean = false;
403 address dest = ic_destination();
404 is_clean = dest == _call->get_resolve_call_stub(is_optimized());
405 assert(!is_clean || is_optimized() || cached_value() == nullptr, "sanity check");
406 return is_clean;
407 }
408
409 bool CompiledIC::set_to_monomorphic(CompiledICInfo& info) {
410 assert(CompiledICLocker::is_safe(_method), "mt unsafe call");
411 // Updating a cache to the wrong entry can cause bugs that are very hard
412 // to track down - if cache entry gets invalid - we just clean it. In
413 // this way it is always the same code path that is responsible for
414 // updating and resolving an inline cache
415 //
416 // The above is no longer true. SharedRuntime::fixup_callers_callsite will change optimized
417 // callsites. In addition ic_miss code will update a site to monomorphic if it determines
418 // that an monomorphic call to the interpreter can now be monomorphic to compiled code.
419 //
420 // In both of these cases the only thing being modified is the jump/call target and these
421 // transitions are mt_safe
422
423 Thread *thread = Thread::current();
424 if (info.to_interpreter()) {
425 // Call to interpreter
426 if (info.is_optimized() && is_optimized()) {
427 assert(is_clean(), "unsafe IC path");
428 // the call analysis (callee structure) specifies that the call is optimized
429 // (either because of CHA or the static target is final)
430 // At code generation time, this call has been emitted as static call
431 // Call via stub
432 assert(info.cached_metadata() != nullptr && info.cached_metadata()->is_method(), "sanity check");
433 methodHandle method (thread, (Method*)info.cached_metadata());
434 _call->set_to_interpreted(method, info);
435
436 if (TraceICs) {
437 ResourceMark rm(thread);
438 tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter: %s",
439 p2i(instruction_address()),
440 method->print_value_string());
441 }
442 } else {
443 // Call via method-klass-holder
444 CompiledICHolder* holder = info.claim_cached_icholder();
445 if (!InlineCacheBuffer::create_transition_stub(this, holder, info.entry())) {
446 delete holder;
447 return false;
448 }
449 // LSan appears unable to follow malloc-based memory consistently when embedded as an
450 // immediate in generated machine code. So we have to ignore it.
451 LSAN_IGNORE_OBJECT(holder);
452 if (TraceICs) {
453 ResourceMark rm(thread);
454 tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter via icholder ", p2i(instruction_address()));
455 }
456 }
457 } else {
458 // Call to compiled code
459 bool static_bound = info.is_optimized() || (info.cached_metadata() == nullptr);
460 #ifdef ASSERT
461 CodeBlob* cb = CodeCache::find_blob(info.entry());
462 assert (cb != nullptr && cb->is_compiled(), "must be compiled!");
463 #endif /* ASSERT */
464
465 // This is MT safe if we come from a clean-cache and go through a
466 // non-verified entry point
467 bool safe = SafepointSynchronize::is_at_safepoint() ||
468 (!is_in_transition_state() && (info.is_optimized() || static_bound || is_clean()));
469
470 if (!safe) {
471 if (!InlineCacheBuffer::create_transition_stub(this, info.cached_metadata(), info.entry())) {
472 return false;
473 }
474 } else {
475 if (is_optimized()) {
476 set_ic_destination(info.entry());
477 } else {
478 set_ic_destination_and_value(info.entry(), info.cached_metadata());
479 }
480 }
481
482 if (TraceICs) {
483 ResourceMark rm(thread);
484 assert(info.cached_metadata() == nullptr || info.cached_metadata()->is_klass(), "must be");
485 tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to compiled (rcvr klass = %s) %s",
486 p2i(instruction_address()),
487 (info.cached_metadata() != nullptr) ? ((Klass*)info.cached_metadata())->print_value_string() : "nullptr",
488 (safe) ? "" : " via stub");
489 }
490 }
491 // We can't check this anymore. With lazy deopt we could have already
492 // cleaned this IC entry before we even return. This is possible if
493 // we ran out of space in the inline cache buffer trying to do the
494 // set_next and we safepointed to free up space. This is a benign
495 // race because the IC entry was complete when we safepointed so
496 // cleaning it immediately is harmless.
497 // assert(is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
498 return true;
499 }
500
501
502 // is_optimized: Compiler has generated an optimized call (i.e. fixed, no inline cache)
503 // static_bound: The call can be static bound. If it isn't also optimized, the property
504 // wasn't provable at time of compilation. An optimized call will have any necessary
505 // null check, while a static_bound won't. A static_bound (but not optimized) must
506 // therefore use the unverified entry point.
507 void CompiledIC::compute_monomorphic_entry(const methodHandle& method,
508 Klass* receiver_klass,
509 bool is_optimized,
510 bool static_bound,
511 bool caller_is_nmethod,
512 CompiledICInfo& info,
513 TRAPS) {
514 CompiledMethod* method_code = method->code();
515
516 address entry = nullptr;
517 if (method_code != nullptr && method_code->is_in_use() && !method_code->is_unloading()) {
518 assert(method_code->is_compiled(), "must be compiled");
519 // Call to compiled code
520 //
521 // Note: the following problem exists with Compiler1:
522 // - at compile time we may or may not know if the destination is final
523 // - if we know that the destination is final (is_optimized), we will emit
524 // an optimized virtual call (no inline cache), and need a Method* to make
525 // a call to the interpreter
526 // - if we don't know if the destination is final, we emit a standard
527 // virtual call, and use CompiledICHolder to call interpreted code
528 // (no static call stub has been generated)
529 // - In the case that we here notice the call is static bound we
530 // convert the call into what looks to be an optimized virtual call,
531 // but we must use the unverified entry point (since there will be no
532 // null check on a call when the target isn't loaded).
533 // This causes problems when verifying the IC because
534 // it looks vanilla but is optimized. Code in is_call_to_interpreted
535 // is aware of this and weakens its asserts.
536 if (is_optimized) {
537 entry = method_code->verified_entry_point();
538 } else {
539 entry = method_code->entry_point();
540 }
541 }
542 if (entry != nullptr) {
543 // Call to near compiled code.
544 info.set_compiled_entry(entry, is_optimized ? nullptr : receiver_klass, is_optimized);
545 } else {
546 if (is_optimized) {
547 // Use stub entry
548 info.set_interpreter_entry(method()->get_c2i_entry(), method());
549 } else {
550 // Use icholder entry
551 assert(method_code == nullptr || method_code->is_compiled(), "must be compiled");
552 CompiledICHolder* holder = new CompiledICHolder(method(), receiver_klass);
553 info.set_icholder_entry(method()->get_c2i_unverified_entry(), holder);
554 }
555 }
556 assert(info.is_optimized() == is_optimized, "must agree");
557 }
558
559
560 bool CompiledIC::is_icholder_entry(address entry) {
561 CodeBlob* cb = CodeCache::find_blob(entry);
562 if (cb == nullptr) {
563 return false;
564 }
565 if (cb->is_adapter_blob()) {
566 return true;
567 } else if (cb->is_vtable_blob()) {
568 return VtableStubs::is_icholder_entry(entry);
569 }
570 return false;
571 }
572
573 bool CompiledIC::is_icholder_call_site(virtual_call_Relocation* call_site, const CompiledMethod* cm) {
574 // This call site might have become stale so inspect it carefully.
575 address dest = cm->call_wrapper_at(call_site->addr())->destination();
576 return is_icholder_entry(dest);
577 }
578
579 // ----------------------------------------------------------------------------
580
581 bool CompiledStaticCall::set_to_clean(bool in_use) {
582 // in_use is unused but needed to match template function in CompiledMethod
583 assert(CompiledICLocker::is_safe(instruction_address()), "mt unsafe call");
584 // Reset call site
585 set_destination_mt_safe(resolve_call_stub());
586
587 // Do not reset stub here: It is too expensive to call find_stub.
588 // Instead, rely on caller (nmethod::clear_inline_caches) to clear
589 // both the call and its stub.
590 return true;
591 }
592
593 bool CompiledStaticCall::is_clean() const {
594 return destination() == resolve_call_stub();
595 }
596
597 bool CompiledStaticCall::is_call_to_compiled() const {
598 return CodeCache::contains(destination());
599 }
600
601 bool CompiledDirectStaticCall::is_call_to_interpreted() const {
602 // It is a call to interpreted, if it calls to a stub. Hence, the destination
603 // must be in the stub part of the nmethod that contains the call
604 CompiledMethod* cm = CodeCache::find_compiled(instruction_address());
605 return cm->stub_contains(destination());
606 }
607
608 void CompiledStaticCall::set_to_compiled(address entry) {
609 if (TraceICs) {
610 ResourceMark rm;
611 tty->print_cr("%s@" INTPTR_FORMAT ": set_to_compiled " INTPTR_FORMAT,
612 name(),
613 p2i(instruction_address()),
614 p2i(entry));
615 }
616 // Call to compiled code
617 assert(CodeCache::contains(entry), "wrong entry point");
618 set_destination_mt_safe(entry);
619 }
620
621 void CompiledStaticCall::set(const StaticCallInfo& info) {
622 assert(CompiledICLocker::is_safe(instruction_address()), "mt unsafe call");
623 // Updating a cache to the wrong entry can cause bugs that are very hard
624 // to track down - if cache entry gets invalid - we just clean it. In
625 // this way it is always the same code path that is responsible for
626 // updating and resolving an inline cache
627 assert(is_clean(), "do not update a call entry - use clean");
628
629 if (info._to_interpreter) {
630 // Call to interpreted code
631 set_to_interpreted(info.callee(), info.entry());
632 } else {
633 set_to_compiled(info.entry());
634 }
635 }
636
637 // Compute settings for a CompiledStaticCall. Since we might have to set
638 // the stub when calling to the interpreter, we need to return arguments.
639 void CompiledStaticCall::compute_entry(const methodHandle& m, bool caller_is_nmethod, StaticCallInfo& info) {
640 CompiledMethod* m_code = m->code();
641 info._callee = m;
642 if (m_code != nullptr && m_code->is_in_use() && !m_code->is_unloading()) {
643 info._to_interpreter = false;
644 info._entry = m_code->verified_entry_point();
645 } else {
646 // Callee is interpreted code. In any case entering the interpreter
647 // puts a converter-frame on the stack to save arguments.
648 assert(!m->is_method_handle_intrinsic(), "Compiled code should never call interpreter MH intrinsics");
649 info._to_interpreter = true;
650 info._entry = m()->get_c2i_entry();
651 }
652 }
653
654 void CompiledStaticCall::compute_entry_for_continuation_entry(const methodHandle& m, StaticCallInfo& info) {
655 if (ContinuationEntry::is_interpreted_call(instruction_address())) {
656 info._to_interpreter = true;
657 info._entry = m()->get_c2i_entry();
658 }
659 }
660
661 address CompiledDirectStaticCall::find_stub_for(address instruction) {
662 // Find reloc. information containing this call-site
663 RelocIterator iter((nmethod*)nullptr, instruction);
664 while (iter.next()) {
665 if (iter.addr() == instruction) {
666 switch(iter.type()) {
667 case relocInfo::static_call_type:
668 return iter.static_call_reloc()->static_stub();
669 // We check here for opt_virtual_call_type, since we reuse the code
670 // from the CompiledIC implementation
671 case relocInfo::opt_virtual_call_type:
672 return iter.opt_virtual_call_reloc()->static_stub();
673 case relocInfo::poll_type:
674 case relocInfo::poll_return_type: // A safepoint can't overlap a call.
675 default:
676 ShouldNotReachHere();
677 }
678 }
679 }
680 return nullptr;
681 }
682
683 address CompiledDirectStaticCall::find_stub() {
684 return CompiledDirectStaticCall::find_stub_for(instruction_address());
685 }
686
687 address CompiledDirectStaticCall::resolve_call_stub() const {
688 return SharedRuntime::get_resolve_static_call_stub();
689 }
690
691 //-----------------------------------------------------------------------------
692 // Non-product mode code
693 #ifndef PRODUCT
694
695 void CompiledIC::verify() {
696 _call->verify();
697 assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted()
698 || is_optimized() || is_megamorphic(), "sanity check");
699 }
700
701 void CompiledIC::print() {
702 print_compiled_ic();
703 tty->cr();
704 }
705
706 void CompiledIC::print_compiled_ic() {
707 tty->print("Inline cache at " INTPTR_FORMAT ", calling %s " INTPTR_FORMAT " cached_value " INTPTR_FORMAT,
708 p2i(instruction_address()), is_call_to_interpreted() ? "interpreted " : "", p2i(ic_destination()), p2i(is_optimized() ? nullptr : cached_value()));
709 }
710
711 void CompiledDirectStaticCall::print() {
712 tty->print("static call at " INTPTR_FORMAT " -> ", p2i(instruction_address()));
713 if (is_clean()) {
714 tty->print("clean");
715 } else if (is_call_to_compiled()) {
716 tty->print("compiled");
717 } else if (is_call_to_interpreted()) {
718 tty->print("interpreted");
719 }
720 tty->cr();
721 }
722
723 void CompiledDirectStaticCall::verify_mt_safe(const methodHandle& callee, address entry,
724 NativeMovConstReg* method_holder,
725 NativeJump* jump) {
726 // A generated lambda form might be deleted from the Lambdaform
727 // cache in MethodTypeForm. If a jit compiled lambdaform method
728 // becomes not entrant and the cache access returns null, the new
729 // resolve will lead to a new generated LambdaForm.
730 Method* old_method = reinterpret_cast<Method*>(method_holder->data());
731 assert(old_method == nullptr || old_method == callee() ||
732 callee->is_compiled_lambda_form() ||
733 !old_method->method_holder()->is_loader_alive() ||
734 old_method->is_old(), // may be race patching deoptimized nmethod due to redefinition.
735 "a) MT-unsafe modification of inline cache");
736
737 address destination = jump->jump_destination();
738 assert(destination == (address)-1 || destination == entry
739 || old_method == nullptr || !old_method->method_holder()->is_loader_alive() // may have a race due to class unloading.
740 || old_method->is_old(), // may be race patching deoptimized nmethod due to redefinition.
741 "b) MT-unsafe modification of inline cache");
742 }
743 #endif // !PRODUCT