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.
 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.
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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, bool caller_is_c1, 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, caller_is_c1);
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, caller_is_c1);
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                                            bool caller_is_c1,
513                                            CompiledICInfo& info,
514                                            TRAPS) {
515   CompiledMethod* method_code = method->code();
516 
517   address entry = nullptr;
518   if (method_code != nullptr && method_code->is_in_use() && !method_code->is_unloading()) {
519     assert(method_code->is_compiled(), "must be compiled");
520     // Call to compiled code
521     //
522     // Note: the following problem exists with Compiler1:
523     //   - at compile time we may or may not know if the destination is final
524     //   - if we know that the destination is final (is_optimized), we will emit
525     //     an optimized virtual call (no inline cache), and need a Method* to make
526     //     a call to the interpreter
527     //   - if we don't know if the destination is final, we emit a standard
528     //     virtual call, and use CompiledICHolder to call interpreted code
529     //     (no static call stub has been generated)
530     //   - In the case that we here notice the call is static bound we
531     //     convert the call into what looks to be an optimized virtual call,
532     //     but we must use the unverified entry point (since there will be no
533     //     null check on a call when the target isn't loaded).
534     //     This causes problems when verifying the IC because
535     //     it looks vanilla but is optimized. Code in is_call_to_interpreted
536     //     is aware of this and weakens its asserts.
537     if (is_optimized) {
538       entry      = caller_is_c1 ? method_code->verified_inline_entry_point() : method_code->verified_entry_point();
539     } else {
540       entry      = caller_is_c1 ? method_code->inline_entry_point() : method_code->entry_point();
541     }
542   }
543   if (entry != nullptr) {
544     // Call to near compiled code.
545     info.set_compiled_entry(entry, is_optimized ? nullptr : receiver_klass, is_optimized);
546   } else {
547     if (is_optimized) {
548       // Use stub entry
549       address entry = caller_is_c1 ? method()->get_c2i_inline_entry() : method()->get_c2i_entry();
550       info.set_interpreter_entry(entry, method());
551     } else {
552       // Use icholder entry
553       assert(method_code == nullptr || method_code->is_compiled(), "must be compiled");
554       CompiledICHolder* holder = new CompiledICHolder(method(), receiver_klass);
555       entry = (caller_is_c1)? method()->get_c2i_unverified_inline_entry() : method()->get_c2i_unverified_entry();
556       info.set_icholder_entry(entry, holder);
557     }
558   }
559   assert(info.is_optimized() == is_optimized, "must agree");
560 }
561 
562 
563 bool CompiledIC::is_icholder_entry(address entry) {
564   CodeBlob* cb = CodeCache::find_blob(entry);
565   if (cb == nullptr) {
566     return false;
567   }
568   if (cb->is_adapter_blob()) {
569     return true;
570   } else if (cb->is_vtable_blob()) {
571     return VtableStubs::is_icholder_entry(entry);
572   }
573   return false;
574 }
575 
576 bool CompiledIC::is_icholder_call_site(virtual_call_Relocation* call_site, const CompiledMethod* cm) {
577   // This call site might have become stale so inspect it carefully.
578   address dest = cm->call_wrapper_at(call_site->addr())->destination();
579   return is_icholder_entry(dest);
580 }
581 
582 // ----------------------------------------------------------------------------
583 
584 bool CompiledStaticCall::set_to_clean(bool in_use) {
585   // in_use is unused but needed to match template function in CompiledMethod
586   assert(CompiledICLocker::is_safe(instruction_address()), "mt unsafe call");
587   // Reset call site
588   set_destination_mt_safe(resolve_call_stub());
589 
590   // Do not reset stub here:  It is too expensive to call find_stub.
591   // Instead, rely on caller (nmethod::clear_inline_caches) to clear
592   // both the call and its stub.
593   return true;
594 }
595 
596 bool CompiledStaticCall::is_clean() const {
597   return destination() == resolve_call_stub();
598 }
599 
600 bool CompiledStaticCall::is_call_to_compiled() const {
601   return CodeCache::contains(destination());
602 }
603 
604 bool CompiledDirectStaticCall::is_call_to_interpreted() const {
605   // It is a call to interpreted, if it calls to a stub. Hence, the destination
606   // must be in the stub part of the nmethod that contains the call
607   CompiledMethod* cm = CodeCache::find_compiled(instruction_address());
608   return cm->stub_contains(destination());
609 }
610 
611 void CompiledStaticCall::set_to_compiled(address entry) {
612   if (TraceICs) {
613     ResourceMark rm;
614     tty->print_cr("%s@" INTPTR_FORMAT ": set_to_compiled " INTPTR_FORMAT,
615         name(),
616         p2i(instruction_address()),
617         p2i(entry));
618   }
619   // Call to compiled code
620   assert(CodeCache::contains(entry), "wrong entry point");
621   set_destination_mt_safe(entry);
622 }
623 
624 void CompiledStaticCall::set(const StaticCallInfo& info) {
625   assert(CompiledICLocker::is_safe(instruction_address()), "mt unsafe call");
626   // Updating a cache to the wrong entry can cause bugs that are very hard
627   // to track down - if cache entry gets invalid - we just clean it. In
628   // this way it is always the same code path that is responsible for
629   // updating and resolving an inline cache
630   assert(is_clean(), "do not update a call entry - use clean");
631 
632   if (info._to_interpreter) {
633     // Call to interpreted code
634     set_to_interpreted(info.callee(), info.entry());
635   } else {
636     set_to_compiled(info.entry());
637   }
638 }
639 
640 // Compute settings for a CompiledStaticCall. Since we might have to set
641 // the stub when calling to the interpreter, we need to return arguments.
642 void CompiledStaticCall::compute_entry(const methodHandle& m, CompiledMethod* caller_nm, StaticCallInfo& info) {
643   assert(!m->mismatch(), "Mismatch for static call");
644   bool caller_is_nmethod = caller_nm->is_nmethod();
645   CompiledMethod* m_code = m->code();
646   info._callee = m;
647   if (m_code != nullptr && m_code->is_in_use() && !m_code->is_unloading()) {
648     info._to_interpreter = false;
649     if (caller_nm->is_compiled_by_c1()) {
650       info._entry = m_code->verified_inline_entry_point();
651     } else {
652       info._entry = m_code->verified_entry_point();
653     }
654   } else {
655     // Callee is interpreted code.  In any case entering the interpreter
656     // puts a converter-frame on the stack to save arguments.
657     assert(!m->is_method_handle_intrinsic(), "Compiled code should never call interpreter MH intrinsics");
658     info._to_interpreter = true;
659     if (caller_nm->is_compiled_by_c1()) {
660       // C1 -> interp: values passed as oops
661       info._entry = m()->get_c2i_inline_entry();
662     } else {
663       // C2 -> interp: values passed as fields
664       info._entry = m()->get_c2i_entry();
665     }
666   }
667 }
668 
669 void CompiledStaticCall::compute_entry_for_continuation_entry(const methodHandle& m, StaticCallInfo& info) {
670   if (ContinuationEntry::is_interpreted_call(instruction_address())) {
671     info._to_interpreter = true;
672     info._entry = m()->get_c2i_entry();
673   }
674 }
675 
676 address CompiledDirectStaticCall::find_stub_for(address instruction) {
677   // Find reloc. information containing this call-site
678   RelocIterator iter((nmethod*)nullptr, instruction);
679   while (iter.next()) {
680     if (iter.addr() == instruction) {
681       switch(iter.type()) {
682         case relocInfo::static_call_type:
683           return iter.static_call_reloc()->static_stub();
684         // We check here for opt_virtual_call_type, since we reuse the code
685         // from the CompiledIC implementation
686         case relocInfo::opt_virtual_call_type:
687           return iter.opt_virtual_call_reloc()->static_stub();
688         case relocInfo::poll_type:
689         case relocInfo::poll_return_type: // A safepoint can't overlap a call.
690         default:
691           ShouldNotReachHere();
692       }
693     }
694   }
695   return nullptr;
696 }
697 
698 address CompiledDirectStaticCall::find_stub() {
699   return CompiledDirectStaticCall::find_stub_for(instruction_address());
700 }
701 
702 address CompiledDirectStaticCall::resolve_call_stub() const {
703   return SharedRuntime::get_resolve_static_call_stub();
704 }
705 
706 //-----------------------------------------------------------------------------
707 // Non-product mode code
708 #ifndef PRODUCT
709 
710 void CompiledIC::verify() {
711   _call->verify();
712   assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted()
713           || is_optimized() || is_megamorphic(), "sanity check");
714 }
715 
716 void CompiledIC::print() {
717   print_compiled_ic();
718   tty->cr();
719 }
720 
721 void CompiledIC::print_compiled_ic() {
722   tty->print("Inline cache at " INTPTR_FORMAT ", calling %s " INTPTR_FORMAT " cached_value " INTPTR_FORMAT,
723              p2i(instruction_address()), is_call_to_interpreted() ? "interpreted " : "", p2i(ic_destination()), p2i(is_optimized() ? nullptr : cached_value()));
724 }
725 
726 void CompiledDirectStaticCall::print() {
727   tty->print("static call at " INTPTR_FORMAT " -> ", p2i(instruction_address()));
728   if (is_clean()) {
729     tty->print("clean");
730   } else if (is_call_to_compiled()) {
731     tty->print("compiled");
732   } else if (is_call_to_interpreted()) {
733     tty->print("interpreted");
734   }
735   tty->cr();
736 }
737 
738 void CompiledDirectStaticCall::verify_mt_safe(const methodHandle& callee, address entry,
739                                               NativeMovConstReg* method_holder,
740                                               NativeJump*        jump) {
741   // A generated lambda form might be deleted from the Lambdaform
742   // cache in MethodTypeForm.  If a jit compiled lambdaform method
743   // becomes not entrant and the cache access returns null, the new
744   // resolve will lead to a new generated LambdaForm.
745   Method* old_method = reinterpret_cast<Method*>(method_holder->data());
746   assert(old_method == nullptr || old_method == callee() ||
747          callee->is_compiled_lambda_form() ||
748          !old_method->method_holder()->is_loader_alive() ||
749          old_method->is_old(),  // may be race patching deoptimized nmethod due to redefinition.
750          "a) MT-unsafe modification of inline cache");
751 
752   address destination = jump->jump_destination();
753   assert(destination == (address)-1 || destination == entry
754          || old_method == nullptr || !old_method->method_holder()->is_loader_alive() // may have a race due to class unloading.
755          || old_method->is_old(),  // may be race patching deoptimized nmethod due to redefinition.
756          "b) MT-unsafe modification of inline cache");
757 }
758 #endif // !PRODUCT