38 #include "oops/oop.inline.hpp"
39 #include "oops/symbol.hpp"
40 #include "runtime/icache.hpp"
41 #include "runtime/sharedRuntime.hpp"
42 #include "runtime/stubRoutines.hpp"
43 #include "utilities/events.hpp"
44
45
46 // Every time a compiled IC is changed or its type is being accessed,
47 // either the CompiledIC_lock must be set or we must be at a safe point.
48
49 //-----------------------------------------------------------------------------
50 // Low-level access to an inline cache. Private, since they might not be
51 // MT-safe to use.
52
53 void* CompiledIC::cached_value() const {
54 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
55 assert (!is_optimized(), "an optimized virtual call does not have a cached metadata");
56
57 if (!is_in_transition_state()) {
58 void* data = (void*)_value->data();
59 // If we let the metadata value here be initialized to zero...
60 assert(data != NULL || Universe::non_oop_word() == NULL,
61 "no raw nulls in CompiledIC metadatas, because of patching races");
62 return (data == (void*)Universe::non_oop_word()) ? NULL : data;
63 } else {
64 return InlineCacheBuffer::cached_value_for((CompiledIC *)this);
65 }
66 }
67
68
69 void CompiledIC::internal_set_ic_destination(address entry_point, bool is_icstub, void* cache, bool is_icholder) {
70 assert(entry_point != NULL, "must set legal entry point");
71 assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
72 assert (!is_optimized() || cache == NULL, "an optimized virtual call does not have a cached metadata");
73 assert (cache == NULL || cache != (Metadata*)badOopVal, "invalid metadata");
74
75 assert(!is_icholder || is_icholder_entry(entry_point), "must be");
76
77 // Don't use ic_destination for this test since that forwards
78 // through ICBuffer instead of returning the actual current state of
79 // the CompiledIC.
80 if (is_icholder_entry(_ic_call->destination())) {
81 // When patching for the ICStub case the cached value isn't
82 // overwritten until the ICStub copied into the CompiledIC during
83 // the next safepoint. Make sure that the CompiledICHolder* is
84 // marked for release at this point since it won't be identifiable
85 // once the entry point is overwritten.
86 InlineCacheBuffer::queue_for_release((CompiledICHolder*)_value->data());
87 }
88
89 if (TraceCompiledIC) {
90 tty->print(" ");
91 print_compiled_ic();
92 tty->print(" changing destination to " INTPTR_FORMAT, p2i(entry_point));
93 if (!is_optimized()) {
94 tty->print(" changing cached %s to " INTPTR_FORMAT, is_icholder ? "icholder" : "metadata", p2i((address)cache));
95 }
96 if (is_icstub) {
97 tty->print(" (icstub)");
98 }
99 tty->cr();
100 }
101
102 {
103 MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
104 #ifdef ASSERT
105 CodeBlob* cb = CodeCache::find_blob_unsafe(_ic_call);
106 assert(cb != NULL && cb->is_compiled(), "must be compiled");
107 #endif
108 _ic_call->set_destination_mt_safe(entry_point);
109 }
110
111 if (is_optimized() || is_icstub) {
112 // Optimized call sites don't have a cache value and ICStub call
113 // sites only change the entry point. Changing the value in that
114 // case could lead to MT safety issues.
115 assert(cache == NULL, "must be null");
116 return;
117 }
118
119 if (cache == NULL) cache = (void*)Universe::non_oop_word();
120
121 _value->set_data((intptr_t)cache);
122 }
123
124
125 void CompiledIC::set_ic_destination(ICStub* stub) {
126 internal_set_ic_destination(stub->code_begin(), true, NULL, false);
127 }
128
129
130
131 address CompiledIC::ic_destination() const {
132 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
133 if (!is_in_transition_state()) {
134 return _ic_call->destination();
135 } else {
136 return InlineCacheBuffer::ic_destination_for((CompiledIC *)this);
137 }
138 }
139
140
141 bool CompiledIC::is_in_transition_state() const {
142 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
143 return InlineCacheBuffer::contains(_ic_call->destination());
144 }
145
146
147 bool CompiledIC::is_icholder_call() const {
148 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
149 return !_is_optimized && is_icholder_entry(ic_destination());
150 }
151
152 // Returns native address of 'call' instruction in inline-cache. Used by
153 // the InlineCacheBuffer when it needs to find the stub.
154 address CompiledIC::stub_address() const {
155 assert(is_in_transition_state(), "should only be called when we are in a transition state");
156 return _ic_call->destination();
157 }
158
159 // Clears the IC stub if the compiled IC is in transition state
160 void CompiledIC::clear_ic_stub() {
161 if (is_in_transition_state()) {
162 ICStub* stub = ICStub_from_destination_address(stub_address());
163 stub->clear();
164 }
165 }
166
167
168 //-----------------------------------------------------------------------------
169 // High-level access to an inline cache. Guaranteed to be MT-safe.
170
171 void CompiledIC::initialize_from_iter(RelocIterator* iter) {
172 assert(iter->addr() == _ic_call->instruction_address(), "must find ic_call");
173
174 if (iter->type() == relocInfo::virtual_call_type) {
175 virtual_call_Relocation* r = iter->virtual_call_reloc();
176 _is_optimized = false;
177 _value = nativeMovConstReg_at(r->cached_value());
178 } else {
179 assert(iter->type() == relocInfo::opt_virtual_call_type, "must be a virtual call");
180 _is_optimized = true;
181 _value = NULL;
182 }
183 }
184
185 CompiledIC::CompiledIC(CompiledMethod* cm, NativeCall* call)
186 : _ic_call(call)
187 {
188 address ic_call = _ic_call->instruction_address();
189
190 assert(ic_call != NULL, "ic_call address must be set");
191 assert(cm != NULL, "must pass compiled method");
192 assert(cm->contains(ic_call), "must be in compiled method");
193
194 // Search for the ic_call at the given address.
195 RelocIterator iter(cm, ic_call, ic_call+1);
196 bool ret = iter.next();
197 assert(ret == true, "relocInfo must exist at this address");
198 assert(iter.addr() == ic_call, "must find ic_call");
199
200 initialize_from_iter(&iter);
201 }
202
203 CompiledIC::CompiledIC(RelocIterator* iter)
204 : _ic_call(nativeCall_at(iter->addr()))
205 {
206 address ic_call = _ic_call->instruction_address();
207
208 CompiledMethod* nm = iter->code();
209 assert(ic_call != NULL, "ic_call address must be set");
210 assert(nm != NULL, "must pass compiled method");
211 assert(nm->contains(ic_call), "must be in compiled method");
212
213 initialize_from_iter(iter);
214 }
215
216 bool CompiledIC::set_to_megamorphic(CallInfo* call_info, Bytecodes::Code bytecode, TRAPS) {
217 assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
218 assert(!is_optimized(), "cannot set an optimized virtual call to megamorphic");
219 assert(is_call_to_compiled() || is_call_to_interpreted(), "going directly to megamorphic?");
220
221 address entry;
222 if (call_info->call_kind() == CallInfo::itable_call) {
223 assert(bytecode == Bytecodes::_invokeinterface, "");
224 int itable_index = call_info->itable_index();
225 entry = VtableStubs::find_itable_stub(itable_index);
226 if (entry == false) {
294 (cached_metadata() != NULL && cached_metadata()->is_klass()), "sanity check");
295 #endif // ASSERT
296 return is_monomorphic;
297 }
298
299
300 bool CompiledIC::is_call_to_interpreted() const {
301 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
302 // Call to interpreter if destination is either calling to a stub (if it
303 // is optimized), or calling to an I2C blob
304 bool is_call_to_interpreted = false;
305 if (!is_optimized()) {
306 // must use unsafe because the destination can be a zombie (and we're cleaning)
307 // and the print_compiled_ic code wants to know if site (in the non-zombie)
308 // is to the interpreter.
309 CodeBlob* cb = CodeCache::find_blob_unsafe(ic_destination());
310 is_call_to_interpreted = (cb != NULL && cb->is_adapter_blob());
311 assert(!is_call_to_interpreted || (is_icholder_call() && cached_icholder() != NULL), "sanity check");
312 } else {
313 // Check if we are calling into our own codeblob (i.e., to a stub)
314 CodeBlob* cb = CodeCache::find_blob(_ic_call->instruction_address());
315 address dest = ic_destination();
316 #ifdef ASSERT
317 {
318 CodeBlob* db = CodeCache::find_blob_unsafe(dest);
319 assert(!db->is_adapter_blob(), "must use stub!");
320 }
321 #endif /* ASSERT */
322 is_call_to_interpreted = cb->contains(dest);
323 }
324 return is_call_to_interpreted;
325 }
326
327
328 void CompiledIC::set_to_clean(bool in_use) {
329 assert(SafepointSynchronize::is_at_safepoint() || CompiledIC_lock->is_locked() , "MT-unsafe call");
330 if (TraceInlineCacheClearing || TraceICs) {
331 tty->print_cr("IC@" INTPTR_FORMAT ": set to clean", p2i(instruction_address()));
332 print();
333 }
334
335 address entry;
336 if (is_optimized()) {
337 entry = SharedRuntime::get_resolve_opt_virtual_call_stub();
338 } else {
339 entry = SharedRuntime::get_resolve_virtual_call_stub();
340 }
341
342 // A zombie transition will always be safe, since the metadata has already been set to NULL, so
343 // we only need to patch the destination
344 bool safe_transition = !in_use || is_optimized() || SafepointSynchronize::is_at_safepoint();
345
346 if (safe_transition) {
347 // Kill any leftover stub we might have too
348 clear_ic_stub();
349 if (is_optimized()) {
350 set_ic_destination(entry);
351 } else {
352 set_ic_destination_and_value(entry, (void*)NULL);
353 }
354 } else {
355 // Unsafe transition - create stub.
356 InlineCacheBuffer::create_transition_stub(this, NULL, entry);
357 }
358 // We can't check this anymore. With lazy deopt we could have already
359 // cleaned this IC entry before we even return. This is possible if
360 // we ran out of space in the inline cache buffer trying to do the
361 // set_next and we safepointed to free up space. This is a benign
362 // race because the IC entry was complete when we safepointed so
363 // cleaning it immediately is harmless.
364 // assert(is_clean(), "sanity check");
365 }
366
367
368 bool CompiledIC::is_clean() const {
369 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
370 bool is_clean = false;
371 address dest = ic_destination();
372 is_clean = dest == SharedRuntime::get_resolve_opt_virtual_call_stub() ||
373 dest == SharedRuntime::get_resolve_virtual_call_stub();
374 assert(!is_clean || is_optimized() || cached_value() == NULL, "sanity check");
375 return is_clean;
376 }
377
378
379 void CompiledIC::set_to_monomorphic(CompiledICInfo& info) {
380 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
381 // Updating a cache to the wrong entry can cause bugs that are very hard
382 // to track down - if cache entry gets invalid - we just clean it. In
383 // this way it is always the same code path that is responsible for
384 // updating and resolving an inline cache
385 //
386 // The above is no longer true. SharedRuntime::fixup_callers_callsite will change optimized
387 // callsites. In addition ic_miss code will update a site to monomorphic if it determines
388 // that an monomorphic call to the interpreter can now be monomorphic to compiled code.
389 //
390 // In both of these cases the only thing being modifed is the jump/call target and these
391 // transitions are mt_safe
392
393 Thread *thread = Thread::current();
394 if (info.to_interpreter()) {
395 // Call to interpreter
396 if (info.is_optimized() && is_optimized()) {
397 assert(is_clean(), "unsafe IC path");
398 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
399 // the call analysis (callee structure) specifies that the call is optimized
400 // (either because of CHA or the static target is final)
401 // At code generation time, this call has been emitted as static call
402 // Call via stub
403 assert(info.cached_metadata() != NULL && info.cached_metadata()->is_method(), "sanity check");
404 CompiledStaticCall* csc = compiledStaticCall_at(instruction_address());
405 methodHandle method (thread, (Method*)info.cached_metadata());
406 csc->set_to_interpreted(method, info.entry());
407 if (TraceICs) {
408 ResourceMark rm(thread);
409 tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter: %s",
410 p2i(instruction_address()),
411 method->print_value_string());
412 }
413 } else {
414 // Call via method-klass-holder
415 InlineCacheBuffer::create_transition_stub(this, info.claim_cached_icholder(), info.entry());
416 if (TraceICs) {
417 ResourceMark rm(thread);
418 tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter via icholder ", p2i(instruction_address()));
419 }
420 }
421 } else {
422 // Call to compiled code
423 bool static_bound = info.is_optimized() || (info.cached_metadata() == NULL);
424 #ifdef ASSERT
425 CodeBlob* cb = CodeCache::find_blob_unsafe(info.entry());
426 assert (cb->is_compiled(), "must be compiled!");
427 #endif /* ASSERT */
428
429 // This is MT safe if we come from a clean-cache and go through a
430 // non-verified entry point
450 (safe) ? "" : "via stub");
451 }
452 }
453 // We can't check this anymore. With lazy deopt we could have already
454 // cleaned this IC entry before we even return. This is possible if
455 // we ran out of space in the inline cache buffer trying to do the
456 // set_next and we safepointed to free up space. This is a benign
457 // race because the IC entry was complete when we safepointed so
458 // cleaning it immediately is harmless.
459 // assert(is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
460 }
461
462
463 // is_optimized: Compiler has generated an optimized call (i.e., no inline
464 // cache) static_bound: The call can be static bound (i.e, no need to use
465 // inline cache)
466 void CompiledIC::compute_monomorphic_entry(const methodHandle& method,
467 KlassHandle receiver_klass,
468 bool is_optimized,
469 bool static_bound,
470 CompiledICInfo& info,
471 TRAPS) {
472 CompiledMethod* method_code = method->code();
473
474 address entry = NULL;
475 if (method_code != NULL && method_code->is_in_use()) {
476 assert(method_code->is_compiled(), "must be compiled");
477 // Call to compiled code
478 if (static_bound || is_optimized) {
479 entry = method_code->verified_entry_point();
480 } else {
481 entry = method_code->entry_point();
482 }
483 }
484 if (entry != NULL) {
485 // Call to compiled code
486 info.set_compiled_entry(entry, (static_bound || is_optimized) ? NULL : receiver_klass(), is_optimized);
487 } else {
488 // Note: the following problem exists with Compiler1:
489 // - at compile time we may or may not know if the destination is final
490 // - if we know that the destination is final, we will emit an optimized
491 // virtual call (no inline cache), and need a Method* to make a call
492 // to the interpreter
493 // - if we do not know if the destination is final, we emit a standard
494 // virtual call, and use CompiledICHolder to call interpreted code
495 // (no static call stub has been generated)
496 // However in that case we will now notice it is static_bound
497 // and convert the call into what looks to be an optimized
498 // virtual call. This causes problems in verifying the IC because
499 // it look vanilla but is optimized. Code in is_call_to_interpreted
500 // is aware of this and weakens its asserts.
501
502 // static_bound should imply is_optimized -- otherwise we have a
503 // performance bug (statically-bindable method is called via
504 // dynamically-dispatched call note: the reverse implication isn't
505 // necessarily true -- the call may have been optimized based on compiler
506 // analysis (static_bound is only based on "final" etc.)
507 #ifdef COMPILER2
508 #ifdef TIERED
509 #if defined(ASSERT)
510 // can't check the assert because we don't have the CompiledIC with which to
511 // find the address if the call instruction.
512 //
513 // CodeBlob* cb = find_blob_unsafe(instruction_address());
514 // assert(cb->is_compiled_by_c1() || !static_bound || is_optimized, "static_bound should imply is_optimized");
515 #endif // ASSERT
516 #else
517 assert(!static_bound || is_optimized, "static_bound should imply is_optimized");
518 #endif // TIERED
519 #endif // COMPILER2
520 if (is_optimized) {
521 // Use stub entry
522 info.set_interpreter_entry(method()->get_c2i_entry(), method());
523 } else {
524 // Use icholder entry
525 assert(method_code == NULL || method_code->is_compiled(), "must be compiled");
526 CompiledICHolder* holder = new CompiledICHolder(method(), receiver_klass());
527 info.set_icholder_entry(method()->get_c2i_unverified_entry(), holder);
528 }
529 }
530 assert(info.is_optimized() == is_optimized, "must agree");
531 }
532
533
534 bool CompiledIC::is_icholder_entry(address entry) {
535 CodeBlob* cb = CodeCache::find_blob_unsafe(entry);
536 return (cb != NULL && cb->is_adapter_blob());
537 }
538
539 // Release the CompiledICHolder* associated with this call site is there is one.
540 void CompiledIC::cleanup_call_site(virtual_call_Relocation* call_site) {
541 // This call site might have become stale so inspect it carefully.
542 NativeCall* call = nativeCall_at(call_site->addr());
543 if (is_icholder_entry(call->destination())) {
544 NativeMovConstReg* value = nativeMovConstReg_at(call_site->cached_value());
545 InlineCacheBuffer::queue_for_release((CompiledICHolder*)value->data());
546 }
547 }
548
549 bool CompiledIC::is_icholder_call_site(virtual_call_Relocation* call_site) {
550 // This call site might have become stale so inspect it carefully.
551 NativeCall* call = nativeCall_at(call_site->addr());
552 return is_icholder_entry(call->destination());
553 }
554
555 // ----------------------------------------------------------------------------
556
557 void CompiledStaticCall::set_to_clean() {
558 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
559 // Reset call site
560 MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
561 #ifdef ASSERT
562 CodeBlob* cb = CodeCache::find_blob_unsafe(this);
563 assert(cb != NULL && cb->is_compiled(), "must be compiled");
564 #endif
565 set_destination_mt_safe(SharedRuntime::get_resolve_static_call_stub());
566
567 // Do not reset stub here: It is too expensive to call find_stub.
568 // Instead, rely on caller (nmethod::clear_inline_caches) to clear
569 // both the call and its stub.
570 }
571
572
573 bool CompiledStaticCall::is_clean() const {
574 return destination() == SharedRuntime::get_resolve_static_call_stub();
575 }
576
577 bool CompiledStaticCall::is_call_to_compiled() const {
578 return CodeCache::contains(destination());
579 }
580
581
582 bool CompiledStaticCall::is_call_to_interpreted() const {
583 // It is a call to interpreted, if it calls to a stub. Hence, the destination
584 // must be in the stub part of the nmethod that contains the call
585 CompiledMethod* cm = CodeCache::find_compiled(instruction_address());
586 return cm->stub_contains(destination());
587 }
588
589 void CompiledStaticCall::set(const StaticCallInfo& info) {
590 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
591 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
592 // Updating a cache to the wrong entry can cause bugs that are very hard
593 // to track down - if cache entry gets invalid - we just clean it. In
594 // this way it is always the same code path that is responsible for
595 // updating and resolving an inline cache
596 assert(is_clean(), "do not update a call entry - use clean");
597
598 if (info._to_interpreter) {
599 // Call to interpreted code
600 set_to_interpreted(info.callee(), info.entry());
601 } else {
602 if (TraceICs) {
603 ResourceMark rm;
604 tty->print_cr("CompiledStaticCall@" INTPTR_FORMAT ": set_to_compiled " INTPTR_FORMAT,
605 p2i(instruction_address()),
606 p2i(info.entry()));
607 }
608 // Call to compiled code
609 assert (CodeCache::contains(info.entry()), "wrong entry point");
610 set_destination_mt_safe(info.entry());
611 }
612 }
613
614
615 // Compute settings for a CompiledStaticCall. Since we might have to set
616 // the stub when calling to the interpreter, we need to return arguments.
617 void CompiledStaticCall::compute_entry(const methodHandle& m, StaticCallInfo& info) {
618 CompiledMethod* m_code = m->code();
619 info._callee = m;
620 if (m_code != NULL && m_code->is_in_use()) {
621 info._to_interpreter = false;
622 info._entry = m_code->verified_entry_point();
623 } else {
624 // Callee is interpreted code. In any case entering the interpreter
625 // puts a converter-frame on the stack to save arguments.
626 assert(!m->is_method_handle_intrinsic(), "Compiled code should never call interpreter MH intrinsics");
627 info._to_interpreter = true;
628 info._entry = m()->get_c2i_entry();
629 }
630 }
631
632 address CompiledStaticCall::find_stub() {
633 // Find reloc. information containing this call-site
634 RelocIterator iter((nmethod*)NULL, instruction_address());
635 while (iter.next()) {
636 if (iter.addr() == instruction_address()) {
637 switch(iter.type()) {
638 case relocInfo::static_call_type:
639 return iter.static_call_reloc()->static_stub();
640 // We check here for opt_virtual_call_type, since we reuse the code
641 // from the CompiledIC implementation
642 case relocInfo::opt_virtual_call_type:
643 return iter.opt_virtual_call_reloc()->static_stub();
644 case relocInfo::poll_type:
645 case relocInfo::poll_return_type: // A safepoint can't overlap a call.
646 default:
647 ShouldNotReachHere();
648 }
649 }
650 }
651 return NULL;
652 }
653
654
655 //-----------------------------------------------------------------------------
656 // Non-product mode code
657 #ifndef PRODUCT
658
659 void CompiledIC::verify() {
660 // make sure code pattern is actually a call imm32 instruction
661 _ic_call->verify();
662 if (os::is_MP()) {
663 _ic_call->verify_alignment();
664 }
665 assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted()
666 || is_optimized() || is_megamorphic(), "sanity check");
667 }
668
669 void CompiledIC::print() {
670 print_compiled_ic();
671 tty->cr();
672 }
673
674 void CompiledIC::print_compiled_ic() {
675 tty->print("Inline cache at " INTPTR_FORMAT ", calling %s " INTPTR_FORMAT " cached_value " INTPTR_FORMAT,
676 p2i(instruction_address()), is_call_to_interpreted() ? "interpreted " : "", p2i(ic_destination()), p2i(is_optimized() ? NULL : cached_value()));
677 }
678
679 void CompiledStaticCall::print() {
680 tty->print("static call at " INTPTR_FORMAT " -> ", p2i(instruction_address()));
681 if (is_clean()) {
682 tty->print("clean");
683 } else if (is_call_to_compiled()) {
684 tty->print("compiled");
685 } else if (is_call_to_interpreted()) {
686 tty->print("interpreted");
687 }
688 tty->cr();
689 }
690
691 #endif // !PRODUCT
|
38 #include "oops/oop.inline.hpp"
39 #include "oops/symbol.hpp"
40 #include "runtime/icache.hpp"
41 #include "runtime/sharedRuntime.hpp"
42 #include "runtime/stubRoutines.hpp"
43 #include "utilities/events.hpp"
44
45
46 // Every time a compiled IC is changed or its type is being accessed,
47 // either the CompiledIC_lock must be set or we must be at a safe point.
48
49 //-----------------------------------------------------------------------------
50 // Low-level access to an inline cache. Private, since they might not be
51 // MT-safe to use.
52
53 void* CompiledIC::cached_value() const {
54 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
55 assert (!is_optimized(), "an optimized virtual call does not have a cached metadata");
56
57 if (!is_in_transition_state()) {
58 void* data = get_data();
59 // If we let the metadata value here be initialized to zero...
60 assert(data != NULL || Universe::non_oop_word() == NULL,
61 "no raw nulls in CompiledIC metadatas, because of patching races");
62 return (data == (void*)Universe::non_oop_word()) ? NULL : data;
63 } else {
64 return InlineCacheBuffer::cached_value_for((CompiledIC *)this);
65 }
66 }
67
68
69 void CompiledIC::internal_set_ic_destination(address entry_point, bool is_icstub, void* cache, bool is_icholder) {
70 assert(entry_point != NULL, "must set legal entry point");
71 assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
72 assert (!is_optimized() || cache == NULL, "an optimized virtual call does not have a cached metadata");
73 assert (cache == NULL || cache != (Metadata*)badOopVal, "invalid metadata");
74
75 assert(!is_icholder || is_icholder_entry(entry_point), "must be");
76
77 // Don't use ic_destination for this test since that forwards
78 // through ICBuffer instead of returning the actual current state of
79 // the CompiledIC.
80 if (is_icholder_entry(_call->destination())) {
81 // When patching for the ICStub case the cached value isn't
82 // overwritten until the ICStub copied into the CompiledIC during
83 // the next safepoint. Make sure that the CompiledICHolder* is
84 // marked for release at this point since it won't be identifiable
85 // once the entry point is overwritten.
86 InlineCacheBuffer::queue_for_release((CompiledICHolder*)get_data());
87 }
88
89 if (TraceCompiledIC) {
90 tty->print(" ");
91 print_compiled_ic();
92 tty->print(" changing destination to " INTPTR_FORMAT, p2i(entry_point));
93 if (!is_optimized()) {
94 tty->print(" changing cached %s to " INTPTR_FORMAT, is_icholder ? "icholder" : "metadata", p2i((address)cache));
95 }
96 if (is_icstub) {
97 tty->print(" (icstub)");
98 }
99 tty->cr();
100 }
101
102 {
103 MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
104 #ifdef ASSERT
105 CodeBlob* cb = CodeCache::find_blob_unsafe(_call->instruction_address());
106 assert(cb != NULL && cb->is_compiled(), "must be compiled");
107 #endif
108 _call->set_destination_mt_safe(entry_point);
109 }
110
111 if (is_optimized() || is_icstub) {
112 // Optimized call sites don't have a cache value and ICStub call
113 // sites only change the entry point. Changing the value in that
114 // case could lead to MT safety issues.
115 assert(cache == NULL, "must be null");
116 return;
117 }
118
119 if (cache == NULL) cache = (void*)Universe::non_oop_word();
120
121 set_data((intptr_t)cache);
122 }
123
124
125 void CompiledIC::set_ic_destination(ICStub* stub) {
126 internal_set_ic_destination(stub->code_begin(), true, NULL, false);
127 }
128
129
130
131 address CompiledIC::ic_destination() const {
132 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
133 if (!is_in_transition_state()) {
134 return _call->destination();
135 } else {
136 return InlineCacheBuffer::ic_destination_for((CompiledIC *)this);
137 }
138 }
139
140
141 bool CompiledIC::is_in_transition_state() const {
142 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
143 return InlineCacheBuffer::contains(_call->destination());;
144 }
145
146
147 bool CompiledIC::is_icholder_call() const {
148 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
149 return !_is_optimized && is_icholder_entry(ic_destination());
150 }
151
152 // Returns native address of 'call' instruction in inline-cache. Used by
153 // the InlineCacheBuffer when it needs to find the stub.
154 address CompiledIC::stub_address() const {
155 assert(is_in_transition_state(), "should only be called when we are in a transition state");
156 return _call->destination();
157 }
158
159 // Clears the IC stub if the compiled IC is in transition state
160 void CompiledIC::clear_ic_stub() {
161 if (is_in_transition_state()) {
162 ICStub* stub = ICStub_from_destination_address(stub_address());
163 stub->clear();
164 }
165 }
166
167 //-----------------------------------------------------------------------------
168 // High-level access to an inline cache. Guaranteed to be MT-safe.
169
170 void CompiledIC::initialize_from_iter(RelocIterator* iter) {
171 assert(iter->addr() == _call->instruction_address(), "must find ic_call");
172
173 if (iter->type() == relocInfo::virtual_call_type) {
174 virtual_call_Relocation* r = iter->virtual_call_reloc();
175 _is_optimized = false;
176 _value = _call->get_load_instruction(r);
177 } else {
178 assert(iter->type() == relocInfo::opt_virtual_call_type, "must be a virtual call");
179 _is_optimized = true;
180 _value = NULL;
181 }
182 }
183
184 CompiledIC::CompiledIC(CompiledMethod* cm, NativeCall* call)
185 : _method(cm)
186 {
187 _call = _method->call_wrapper_at((address) call);
188 address ic_call = _call->instruction_address();
189
190 assert(ic_call != NULL, "ic_call address must be set");
191 assert(cm != NULL, "must pass compiled method");
192 assert(cm->contains(ic_call), "must be in compiled method");
193
194 // Search for the ic_call at the given address.
195 RelocIterator iter(cm, ic_call, ic_call+1);
196 bool ret = iter.next();
197 assert(ret == true, "relocInfo must exist at this address");
198 assert(iter.addr() == ic_call, "must find ic_call");
199
200 initialize_from_iter(&iter);
201 }
202
203 CompiledIC::CompiledIC(RelocIterator* iter)
204 : _method(iter->code())
205 {
206 _call = _method->call_wrapper_at(iter->addr());
207 address ic_call = _call->instruction_address();
208
209 CompiledMethod* nm = iter->code();
210 assert(ic_call != NULL, "ic_call address must be set");
211 assert(nm != NULL, "must pass compiled method");
212 assert(nm->contains(ic_call), "must be in compiled method");
213
214 initialize_from_iter(iter);
215 }
216
217 bool CompiledIC::set_to_megamorphic(CallInfo* call_info, Bytecodes::Code bytecode, TRAPS) {
218 assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
219 assert(!is_optimized(), "cannot set an optimized virtual call to megamorphic");
220 assert(is_call_to_compiled() || is_call_to_interpreted(), "going directly to megamorphic?");
221
222 address entry;
223 if (call_info->call_kind() == CallInfo::itable_call) {
224 assert(bytecode == Bytecodes::_invokeinterface, "");
225 int itable_index = call_info->itable_index();
226 entry = VtableStubs::find_itable_stub(itable_index);
227 if (entry == false) {
295 (cached_metadata() != NULL && cached_metadata()->is_klass()), "sanity check");
296 #endif // ASSERT
297 return is_monomorphic;
298 }
299
300
301 bool CompiledIC::is_call_to_interpreted() const {
302 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
303 // Call to interpreter if destination is either calling to a stub (if it
304 // is optimized), or calling to an I2C blob
305 bool is_call_to_interpreted = false;
306 if (!is_optimized()) {
307 // must use unsafe because the destination can be a zombie (and we're cleaning)
308 // and the print_compiled_ic code wants to know if site (in the non-zombie)
309 // is to the interpreter.
310 CodeBlob* cb = CodeCache::find_blob_unsafe(ic_destination());
311 is_call_to_interpreted = (cb != NULL && cb->is_adapter_blob());
312 assert(!is_call_to_interpreted || (is_icholder_call() && cached_icholder() != NULL), "sanity check");
313 } else {
314 // Check if we are calling into our own codeblob (i.e., to a stub)
315 address dest = ic_destination();
316 #ifdef ASSERT
317 {
318 _call->verify_resolve_call(dest);
319 }
320 #endif /* ASSERT */
321 is_call_to_interpreted = _call->is_call_to_interpreted(dest);
322 }
323 return is_call_to_interpreted;
324 }
325
326 void CompiledIC::set_to_clean(bool in_use) {
327 assert(SafepointSynchronize::is_at_safepoint() || CompiledIC_lock->is_locked() , "MT-unsafe call");
328 if (TraceInlineCacheClearing || TraceICs) {
329 tty->print_cr("IC@" INTPTR_FORMAT ": set to clean", p2i(instruction_address()));
330 print();
331 }
332
333 address entry = _call->get_resolve_call_stub(is_optimized());
334
335 // A zombie transition will always be safe, since the metadata has already been set to NULL, so
336 // we only need to patch the destination
337 bool safe_transition = _call->is_safe_for_patching() || !in_use || is_optimized() || SafepointSynchronize::is_at_safepoint();
338
339 if (safe_transition) {
340 // Kill any leftover stub we might have too
341 clear_ic_stub();
342 if (is_optimized()) {
343 set_ic_destination(entry);
344 } else {
345 set_ic_destination_and_value(entry, (void*)NULL);
346 }
347 } else {
348 // Unsafe transition - create stub.
349 InlineCacheBuffer::create_transition_stub(this, NULL, entry);
350 }
351 // We can't check this anymore. With lazy deopt we could have already
352 // cleaned this IC entry before we even return. This is possible if
353 // we ran out of space in the inline cache buffer trying to do the
354 // set_next and we safepointed to free up space. This is a benign
355 // race because the IC entry was complete when we safepointed so
356 // cleaning it immediately is harmless.
357 // assert(is_clean(), "sanity check");
358 }
359
360 bool CompiledIC::is_clean() const {
361 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
362 bool is_clean = false;
363 address dest = ic_destination();
364 is_clean = dest == _call->get_resolve_call_stub(is_optimized());
365 assert(!is_clean || is_optimized() || cached_value() == NULL, "sanity check");
366 return is_clean;
367 }
368
369 void CompiledIC::set_to_monomorphic(CompiledICInfo& info) {
370 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
371 // Updating a cache to the wrong entry can cause bugs that are very hard
372 // to track down - if cache entry gets invalid - we just clean it. In
373 // this way it is always the same code path that is responsible for
374 // updating and resolving an inline cache
375 //
376 // The above is no longer true. SharedRuntime::fixup_callers_callsite will change optimized
377 // callsites. In addition ic_miss code will update a site to monomorphic if it determines
378 // that an monomorphic call to the interpreter can now be monomorphic to compiled code.
379 //
380 // In both of these cases the only thing being modifed is the jump/call target and these
381 // transitions are mt_safe
382
383 Thread *thread = Thread::current();
384 if (info.to_interpreter() || info.to_aot()) {
385 // Call to interpreter
386 if (info.is_optimized() && is_optimized()) {
387 assert(is_clean(), "unsafe IC path");
388 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
389 // the call analysis (callee structure) specifies that the call is optimized
390 // (either because of CHA or the static target is final)
391 // At code generation time, this call has been emitted as static call
392 // Call via stub
393 assert(info.cached_metadata() != NULL && info.cached_metadata()->is_method(), "sanity check");
394 methodHandle method (thread, (Method*)info.cached_metadata());
395 _call->set_to_interpreted(method, info);
396
397 if (TraceICs) {
398 ResourceMark rm(thread);
399 tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to %s: %s",
400 p2i(instruction_address()),
401 (info.to_aot() ? "aot" : "interpreter"),
402 method->print_value_string());
403 }
404 } else {
405 // Call via method-klass-holder
406 InlineCacheBuffer::create_transition_stub(this, info.claim_cached_icholder(), info.entry());
407 if (TraceICs) {
408 ResourceMark rm(thread);
409 tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter via icholder ", p2i(instruction_address()));
410 }
411 }
412 } else {
413 // Call to compiled code
414 bool static_bound = info.is_optimized() || (info.cached_metadata() == NULL);
415 #ifdef ASSERT
416 CodeBlob* cb = CodeCache::find_blob_unsafe(info.entry());
417 assert (cb->is_compiled(), "must be compiled!");
418 #endif /* ASSERT */
419
420 // This is MT safe if we come from a clean-cache and go through a
421 // non-verified entry point
441 (safe) ? "" : "via stub");
442 }
443 }
444 // We can't check this anymore. With lazy deopt we could have already
445 // cleaned this IC entry before we even return. This is possible if
446 // we ran out of space in the inline cache buffer trying to do the
447 // set_next and we safepointed to free up space. This is a benign
448 // race because the IC entry was complete when we safepointed so
449 // cleaning it immediately is harmless.
450 // assert(is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
451 }
452
453
454 // is_optimized: Compiler has generated an optimized call (i.e., no inline
455 // cache) static_bound: The call can be static bound (i.e, no need to use
456 // inline cache)
457 void CompiledIC::compute_monomorphic_entry(const methodHandle& method,
458 KlassHandle receiver_klass,
459 bool is_optimized,
460 bool static_bound,
461 bool caller_is_nmethod,
462 CompiledICInfo& info,
463 TRAPS) {
464 CompiledMethod* method_code = method->code();
465
466 address entry = NULL;
467 if (method_code != NULL && method_code->is_in_use()) {
468 assert(method_code->is_compiled(), "must be compiled");
469 // Call to compiled code
470 if (static_bound || is_optimized) {
471 entry = method_code->verified_entry_point();
472 } else {
473 entry = method_code->entry_point();
474 }
475 }
476 bool far_c2a = entry != NULL && caller_is_nmethod && method_code->is_far_code();
477 if (entry != NULL && !far_c2a) {
478 // Call to near compiled code (nmethod or aot).
479 info.set_compiled_entry(entry, (static_bound || is_optimized) ? NULL : receiver_klass(), is_optimized);
480 } else {
481 // Note: the following problem exists with Compiler1:
482 // - at compile time we may or may not know if the destination is final
483 // - if we know that the destination is final, we will emit an optimized
484 // virtual call (no inline cache), and need a Method* to make a call
485 // to the interpreter
486 // - if we do not know if the destination is final, we emit a standard
487 // virtual call, and use CompiledICHolder to call interpreted code
488 // (no static call stub has been generated)
489 // However in that case we will now notice it is static_bound
490 // and convert the call into what looks to be an optimized
491 // virtual call. This causes problems in verifying the IC because
492 // it look vanilla but is optimized. Code in is_call_to_interpreted
493 // is aware of this and weakens its asserts.
494
495 // static_bound should imply is_optimized -- otherwise we have a
496 // performance bug (statically-bindable method is called via
497 // dynamically-dispatched call note: the reverse implication isn't
498 // necessarily true -- the call may have been optimized based on compiler
499 // analysis (static_bound is only based on "final" etc.)
500 #ifdef COMPILER2
501 #ifdef TIERED
502 #if defined(ASSERT)
503 // can't check the assert because we don't have the CompiledIC with which to
504 // find the address if the call instruction.
505 //
506 // CodeBlob* cb = find_blob_unsafe(instruction_address());
507 // assert(cb->is_compiled_by_c1() || !static_bound || is_optimized, "static_bound should imply is_optimized");
508 #endif // ASSERT
509 #else
510 assert(!static_bound || is_optimized, "static_bound should imply is_optimized");
511 #endif // TIERED
512 #endif // COMPILER2
513 if (is_optimized) {
514 if (far_c2a) {
515 // Call to aot code from nmethod.
516 info.set_aot_entry(entry, method());
517 } else {
518 // Use stub entry
519 info.set_interpreter_entry(method()->get_c2i_entry(), method());
520 }
521 } else {
522 // Use icholder entry
523 assert(method_code == NULL || method_code->is_compiled(), "must be compiled");
524 CompiledICHolder* holder = new CompiledICHolder(method(), receiver_klass());
525 info.set_icholder_entry(method()->get_c2i_unverified_entry(), holder);
526 }
527 }
528 assert(info.is_optimized() == is_optimized, "must agree");
529 }
530
531
532 bool CompiledIC::is_icholder_entry(address entry) {
533 CodeBlob* cb = CodeCache::find_blob_unsafe(entry);
534 return (cb != NULL && cb->is_adapter_blob());
535 }
536
537 bool CompiledIC::is_icholder_call_site(virtual_call_Relocation* call_site, const CompiledMethod* cm) {
538 // This call site might have become stale so inspect it carefully.
539 address dest = cm->call_wrapper_at(call_site->addr())->destination();
540 return is_icholder_entry(dest);
541 }
542
543 // Release the CompiledICHolder* associated with this call site is there is one.
544 void CompiledIC::cleanup_call_site(virtual_call_Relocation* call_site, const CompiledMethod* cm) {
545 assert(cm->is_nmethod(), "must be nmethod");
546 // This call site might have become stale so inspect it carefully.
547 NativeCall* call = nativeCall_at(call_site->addr());
548 if (is_icholder_entry(call->destination())) {
549 NativeMovConstReg* value = nativeMovConstReg_at(call_site->cached_value());
550 InlineCacheBuffer::queue_for_release((CompiledICHolder*)value->data());
551 }
552 }
553
554 // ----------------------------------------------------------------------------
555
556 void CompiledStaticCall::set_to_clean() {
557 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
558 // Reset call site
559 MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
560 #ifdef ASSERT
561 CodeBlob* cb = CodeCache::find_blob_unsafe(instruction_address());
562 assert(cb != NULL && cb->is_compiled(), "must be compiled");
563 #endif
564
565 set_destination_mt_safe(resolve_call_stub());
566
567 // Do not reset stub here: It is too expensive to call find_stub.
568 // Instead, rely on caller (nmethod::clear_inline_caches) to clear
569 // both the call and its stub.
570 }
571
572 bool CompiledStaticCall::is_clean() const {
573 return destination() == resolve_call_stub();
574 }
575
576 bool CompiledStaticCall::is_call_to_compiled() const {
577 return CodeCache::contains(destination());
578 }
579
580 bool CompiledDirectStaticCall::is_call_to_interpreted() const {
581 // It is a call to interpreted, if it calls to a stub. Hence, the destination
582 // must be in the stub part of the nmethod that contains the call
583 CompiledMethod* cm = CodeCache::find_compiled(instruction_address());
584 return cm->stub_contains(destination());
585 }
586
587 bool CompiledDirectStaticCall::is_call_to_far() const {
588 // It is a call to aot method, if it calls to a stub. Hence, the destination
589 // must be in the stub part of the nmethod that contains the call
590 CodeBlob* desc = CodeCache::find_blob(instruction_address());
591 return desc->as_compiled_method()->stub_contains(destination());
592 }
593
594 void CompiledStaticCall::set_to_compiled(address entry) {
595 if (TraceICs) {
596 ResourceMark rm;
597 tty->print_cr("%s@" INTPTR_FORMAT ": set_to_compiled " INTPTR_FORMAT,
598 name(),
599 p2i(instruction_address()),
600 p2i(entry));
601 }
602 // Call to compiled code
603 assert(CodeCache::contains(entry), "wrong entry point");
604 set_destination_mt_safe(entry);
605 }
606
607 void CompiledStaticCall::set(const StaticCallInfo& info) {
608 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
609 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
610 // Updating a cache to the wrong entry can cause bugs that are very hard
611 // to track down - if cache entry gets invalid - we just clean it. In
612 // this way it is always the same code path that is responsible for
613 // updating and resolving an inline cache
614 assert(is_clean(), "do not update a call entry - use clean");
615
616 if (info._to_interpreter) {
617 // Call to interpreted code
618 set_to_interpreted(info.callee(), info.entry());
619 #if INCLUDE_AOT
620 } else if (info._to_aot) {
621 // Call to far code
622 set_to_far(info.callee(), info.entry());
623 #endif
624 } else {
625 set_to_compiled(info.entry());
626 }
627 }
628
629 // Compute settings for a CompiledStaticCall. Since we might have to set
630 // the stub when calling to the interpreter, we need to return arguments.
631 void CompiledStaticCall::compute_entry(const methodHandle& m, bool caller_is_nmethod, StaticCallInfo& info) {
632 CompiledMethod* m_code = m->code();
633 info._callee = m;
634 if (m_code != NULL && m_code->is_in_use()) {
635 if (caller_is_nmethod && m_code->is_far_code()) {
636 // Call to far aot code from nmethod.
637 info._to_aot = true;
638 } else {
639 info._to_aot = false;
640 }
641 info._to_interpreter = false;
642 info._entry = m_code->verified_entry_point();
643 } else {
644 // Callee is interpreted code. In any case entering the interpreter
645 // puts a converter-frame on the stack to save arguments.
646 assert(!m->is_method_handle_intrinsic(), "Compiled code should never call interpreter MH intrinsics");
647 info._to_interpreter = true;
648 info._entry = m()->get_c2i_entry();
649 }
650 }
651
652 address CompiledDirectStaticCall::find_stub_for(address instruction, bool is_aot) {
653 // Find reloc. information containing this call-site
654 RelocIterator iter((nmethod*)NULL, instruction);
655 while (iter.next()) {
656 if (iter.addr() == instruction) {
657 switch(iter.type()) {
658 case relocInfo::static_call_type:
659 return iter.static_call_reloc()->static_stub(is_aot);
660 // We check here for opt_virtual_call_type, since we reuse the code
661 // from the CompiledIC implementation
662 case relocInfo::opt_virtual_call_type:
663 return iter.opt_virtual_call_reloc()->static_stub(is_aot);
664 case relocInfo::poll_type:
665 case relocInfo::poll_return_type: // A safepoint can't overlap a call.
666 default:
667 ShouldNotReachHere();
668 }
669 }
670 }
671 return NULL;
672 }
673
674 address CompiledDirectStaticCall::find_stub(bool is_aot) {
675 return CompiledDirectStaticCall::find_stub_for(instruction_address(), is_aot);
676 }
677
678 address CompiledDirectStaticCall::resolve_call_stub() const {
679 return SharedRuntime::get_resolve_static_call_stub();
680 }
681
682 //-----------------------------------------------------------------------------
683 // Non-product mode code
684 #ifndef PRODUCT
685
686 void CompiledIC::verify() {
687 _call->verify();
688 assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted()
689 || is_optimized() || is_megamorphic(), "sanity check");
690 }
691
692 void CompiledIC::print() {
693 print_compiled_ic();
694 tty->cr();
695 }
696
697 void CompiledIC::print_compiled_ic() {
698 tty->print("Inline cache at " INTPTR_FORMAT ", calling %s " INTPTR_FORMAT " cached_value " INTPTR_FORMAT,
699 p2i(instruction_address()), is_call_to_interpreted() ? "interpreted " : "", p2i(ic_destination()), p2i(is_optimized() ? NULL : cached_value()));
700 }
701
702 void CompiledDirectStaticCall::print() {
703 tty->print("static call at " INTPTR_FORMAT " -> ", p2i(instruction_address()));
704 if (is_clean()) {
705 tty->print("clean");
706 } else if (is_call_to_compiled()) {
707 tty->print("compiled");
708 } else if (is_call_to_far()) {
709 tty->print("far");
710 } else if (is_call_to_interpreted()) {
711 tty->print("interpreted");
712 }
713 tty->cr();
714 }
715
716 #endif // !PRODUCT
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