6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotLinkedClassBulkLoader.hpp"
26 #include "code/scopeDesc.hpp"
27 #include "compiler/compilationPolicy.hpp"
28 #include "compiler/compileBroker.hpp"
29 #include "compiler/compilerDefinitions.inline.hpp"
30 #include "compiler/compilerOracle.hpp"
31 #include "memory/resourceArea.hpp"
32 #include "oops/method.inline.hpp"
33 #include "oops/methodData.hpp"
34 #include "oops/oop.inline.hpp"
35 #include "oops/trainingData.hpp"
36 #include "prims/jvmtiExport.hpp"
37 #include "runtime/arguments.hpp"
38 #include "runtime/deoptimization.hpp"
39 #include "runtime/frame.hpp"
40 #include "runtime/frame.inline.hpp"
41 #include "runtime/globals_extension.hpp"
42 #include "runtime/handles.inline.hpp"
43 #include "runtime/safepoint.hpp"
44 #include "runtime/safepointVerifiers.hpp"
45 #ifdef COMPILER1
46 #include "c1/c1_Compiler.hpp"
47 #endif
48 #ifdef COMPILER2
49 #include "opto/c2compiler.hpp"
50 #endif
51 #if INCLUDE_JVMCI
52 #include "jvmci/jvmci.hpp"
53 #endif
54
55 int64_t CompilationPolicy::_start_time = 0;
56 int CompilationPolicy::_c1_count = 0;
57 int CompilationPolicy::_c2_count = 0;
58 double CompilationPolicy::_increase_threshold_at_ratio = 0;
59
60 CompilationPolicy::TrainingReplayQueue CompilationPolicy::_training_replay_queue;
61
62 void compilationPolicy_init() {
63 CompilationPolicy::initialize();
64 }
65
66 int CompilationPolicy::compiler_count(CompLevel comp_level) {
67 if (is_c1_compile(comp_level)) {
68 return c1_count();
69 } else if (is_c2_compile(comp_level)) {
70 return c2_count();
71 }
72 return 0;
73 }
74
75 // Returns true if m must be compiled before executing it
76 // This is intended to force compiles for methods (usually for
77 // debugging) that would otherwise be interpreted for some reason.
78 bool CompilationPolicy::must_be_compiled(const methodHandle& m, int comp_level) {
79 // Don't allow Xcomp to cause compiles in replay mode
80 if (ReplayCompiles) return false;
81
82 if (m->has_compiled_code()) return false; // already compiled
83 if (!can_be_compiled(m, comp_level)) return false;
84
85 return !UseInterpreter || // must compile all methods
86 (AlwaysCompileLoopMethods && m->has_loops() && CompileBroker::should_compile_new_jobs()); // eagerly compile loop methods
87 }
88
89 void CompilationPolicy::maybe_compile_early(const methodHandle& m, TRAPS) {
90 if (m->method_holder()->is_not_initialized()) {
91 // 'is_not_initialized' means not only '!is_initialized', but also that
92 // initialization has not been started yet ('!being_initialized')
93 // Do not force compilation of methods in uninitialized classes.
94 return;
95 }
96 if (!m->is_native() && MethodTrainingData::have_data()) {
97 MethodTrainingData* mtd = MethodTrainingData::find_fast(m);
98 if (mtd == nullptr) {
99 return; // there is no training data recorded for m
100 }
101 CompLevel cur_level = static_cast<CompLevel>(m->highest_comp_level());
102 CompLevel next_level = trained_transition(m, cur_level, mtd, THREAD);
103 if (next_level != cur_level && can_be_compiled(m, next_level) && !CompileBroker::compilation_is_in_queue(m)) {
104 if (PrintTieredEvents) {
105 print_event(FORCE_COMPILE, m(), m(), InvocationEntryBci, next_level);
106 }
107 CompileBroker::compile_method(m, InvocationEntryBci, next_level, 0, CompileTask::Reason_MustBeCompiled, THREAD);
108 if (HAS_PENDING_EXCEPTION) {
109 CLEAR_PENDING_EXCEPTION;
110 }
111 }
112 }
113 }
114
115 void CompilationPolicy::compile_if_required(const methodHandle& m, TRAPS) {
116 if (!THREAD->can_call_java() || THREAD->is_Compiler_thread()) {
117 // don't force compilation, resolve was on behalf of compiler
118 return;
119 }
120 if (m->method_holder()->is_not_initialized()) {
121 // 'is_not_initialized' means not only '!is_initialized', but also that
122 // initialization has not been started yet ('!being_initialized')
123 // Do not force compilation of methods in uninitialized classes.
124 // Note that doing this would throw an assert later,
125 // in CompileBroker::compile_method.
126 // We sometimes use the link resolver to do reflective lookups
127 // even before classes are initialized.
128 return;
129 }
130
131 if (must_be_compiled(m)) {
132 // This path is unusual, mostly used by the '-Xcomp' stress test mode.
133 CompLevel level = initial_compile_level(m);
134 if (PrintTieredEvents) {
135 print_event(FORCE_COMPILE, m(), m(), InvocationEntryBci, level);
136 }
137 CompileBroker::compile_method(m, InvocationEntryBci, level, 0, CompileTask::Reason_MustBeCompiled, THREAD);
138 }
139 }
140
141 void CompilationPolicy::replay_training_at_init_impl(InstanceKlass* klass, TRAPS) {
142 if (!klass->has_init_deps_processed()) {
143 ResourceMark rm;
144 log_debug(training)("Replay training: %s", klass->external_name());
145
146 KlassTrainingData* ktd = KlassTrainingData::find(klass);
147 if (ktd != nullptr) {
148 guarantee(ktd->has_holder(), "");
149 ktd->notice_fully_initialized(); // sets klass->has_init_deps_processed bit
150 assert(klass->has_init_deps_processed(), "");
151 if (AOTCompileEagerly) {
152 ktd->iterate_comp_deps([&](CompileTrainingData* ctd) {
153 if (ctd->init_deps_left() == 0) {
154 MethodTrainingData* mtd = ctd->method();
155 if (mtd->has_holder()) {
156 const methodHandle mh(THREAD, const_cast<Method*>(mtd->holder()));
157 CompilationPolicy::maybe_compile_early(mh, THREAD);
158 }
159 }
160 });
161 }
162 }
163 }
164 }
165
166 void CompilationPolicy::replay_training_at_init(InstanceKlass* klass, TRAPS) {
167 assert(klass->is_initialized(), "");
168 if (TrainingData::have_data() && klass->is_shared()) {
169 _training_replay_queue.push(klass, TrainingReplayQueue_lock, THREAD);
170 }
171 }
172
173 // For TrainingReplayQueue
174 template<>
175 void CompilationPolicyUtils::Queue<InstanceKlass>::print_on(outputStream* st) {
176 int pos = 0;
177 for (QueueNode* cur = _head; cur != nullptr; cur = cur->next()) {
178 ResourceMark rm;
179 InstanceKlass* ik = cur->value();
180 st->print_cr("%3d: " INTPTR_FORMAT " %s", ++pos, p2i(ik), ik->external_name());
181 }
182 }
183
184 void CompilationPolicy::replay_training_at_init_loop(TRAPS) {
185 while (!CompileBroker::is_compilation_disabled_forever()) {
186 InstanceKlass* ik = _training_replay_queue.pop(TrainingReplayQueue_lock, THREAD);
187 if (ik != nullptr) {
188 replay_training_at_init_impl(ik, THREAD);
189 }
190 }
191 }
192
193 static inline CompLevel adjust_level_for_compilability_query(CompLevel comp_level) {
194 if (comp_level == CompLevel_any) {
195 if (CompilerConfig::is_c1_only()) {
196 comp_level = CompLevel_simple;
197 } else if (CompilerConfig::is_c2_or_jvmci_compiler_only()) {
198 comp_level = CompLevel_full_optimization;
199 }
200 }
201 return comp_level;
202 }
203
204 // Returns true if m is allowed to be compiled
205 bool CompilationPolicy::can_be_compiled(const methodHandle& m, int comp_level) {
455 // Print an event.
456 void CompilationPolicy::print_event(EventType type, Method* m, Method* im, int bci, CompLevel level) {
457 bool inlinee_event = m != im;
458
459 ttyLocker tty_lock;
460 tty->print("%lf: [", os::elapsedTime());
461
462 switch(type) {
463 case CALL:
464 tty->print("call");
465 break;
466 case LOOP:
467 tty->print("loop");
468 break;
469 case COMPILE:
470 tty->print("compile");
471 break;
472 case FORCE_COMPILE:
473 tty->print("force-compile");
474 break;
475 case REMOVE_FROM_QUEUE:
476 tty->print("remove-from-queue");
477 break;
478 case UPDATE_IN_QUEUE:
479 tty->print("update-in-queue");
480 break;
481 case REPROFILE:
482 tty->print("reprofile");
483 break;
484 case MAKE_NOT_ENTRANT:
485 tty->print("make-not-entrant");
486 break;
487 default:
488 tty->print("unknown");
489 }
490
491 tty->print(" level=%d ", level);
492
493 ResourceMark rm;
494 char *method_name = m->name_and_sig_as_C_string();
495 tty->print("[%s", method_name);
496 if (inlinee_event) {
497 char *inlinee_name = im->name_and_sig_as_C_string();
498 tty->print(" [%s]] ", inlinee_name);
499 }
500 else tty->print("] ");
501 tty->print("@%d queues=%d,%d", bci, CompileBroker::queue_size(CompLevel_full_profile),
502 CompileBroker::queue_size(CompLevel_full_optimization));
503
504 tty->print(" rate=");
505 if (m->prev_time() == 0) tty->print("n/a");
506 else tty->print("%f", m->rate());
507
508 tty->print(" k=%.2lf,%.2lf", threshold_scale(CompLevel_full_profile, Tier3LoadFeedback),
509 threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback));
510
511 if (type != COMPILE) {
512 print_counters("", m);
513 if (inlinee_event) {
514 print_counters("inlinee ", im);
515 }
516 tty->print(" compilable=");
517 bool need_comma = false;
518 if (!m->is_not_compilable(CompLevel_full_profile)) {
519 tty->print("c1");
520 need_comma = true;
521 }
522 if (!m->is_not_osr_compilable(CompLevel_full_profile)) {
523 if (need_comma) tty->print(",");
524 tty->print("c1-osr");
525 need_comma = true;
526 }
527 if (!m->is_not_compilable(CompLevel_full_optimization)) {
536 tty->print(" status=");
537 if (m->queued_for_compilation()) {
538 tty->print("in-queue");
539 } else tty->print("idle");
540 print_training_data("", m);
541 if (inlinee_event) {
542 print_training_data("inlinee ", im);
543 }
544 }
545 tty->print_cr("]");
546 }
547
548 void CompilationPolicy::initialize() {
549 if (!CompilerConfig::is_interpreter_only()) {
550 int count = CICompilerCount;
551 bool c1_only = CompilerConfig::is_c1_only();
552 bool c2_only = CompilerConfig::is_c2_or_jvmci_compiler_only();
553
554 #ifdef _LP64
555 // Turn on ergonomic compiler count selection
556 if (FLAG_IS_DEFAULT(CICompilerCountPerCPU) && FLAG_IS_DEFAULT(CICompilerCount)) {
557 FLAG_SET_DEFAULT(CICompilerCountPerCPU, true);
558 }
559 if (CICompilerCountPerCPU) {
560 // Simple log n seems to grow too slowly for tiered, try something faster: log n * log log n
561 int log_cpu = log2i(os::active_processor_count());
562 int loglog_cpu = log2i(MAX2(log_cpu, 1));
563 count = MAX2(log_cpu * loglog_cpu * 3 / 2, 2);
564 // Make sure there is enough space in the code cache to hold all the compiler buffers
565 size_t c1_size = 0;
566 #ifdef COMPILER1
567 c1_size = Compiler::code_buffer_size();
568 #endif
569 size_t c2_size = 0;
570 #ifdef COMPILER2
571 c2_size = C2Compiler::initial_code_buffer_size();
572 #endif
573 size_t buffer_size = c1_only ? c1_size : (c1_size/3 + 2*c2_size/3);
574 int max_count = (ReservedCodeCacheSize - (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3))) / (int)buffer_size;
575 if (count > max_count) {
576 // Lower the compiler count such that all buffers fit into the code cache
577 count = MAX2(max_count, c1_only ? 1 : 2);
578 }
579 FLAG_SET_ERGO(CICompilerCount, count);
580 }
581 #else
582 // On 32-bit systems, the number of compiler threads is limited to 3.
583 // On these systems, the virtual address space available to the JVM
594
595 if (c1_only) {
596 // No C2 compiler thread required
597 set_c1_count(count);
598 } else if (c2_only) {
599 set_c2_count(count);
600 } else {
601 #if INCLUDE_JVMCI
602 if (UseJVMCICompiler && UseJVMCINativeLibrary) {
603 int libjvmci_count = MAX2((int) (count * JVMCINativeLibraryThreadFraction), 1);
604 int c1_count = MAX2(count - libjvmci_count, 1);
605 set_c2_count(libjvmci_count);
606 set_c1_count(c1_count);
607 } else
608 #endif
609 {
610 set_c1_count(MAX2(count / 3, 1));
611 set_c2_count(MAX2(count - c1_count(), 1));
612 }
613 }
614 assert(count == c1_count() + c2_count(), "inconsistent compiler thread count");
615 set_increase_threshold_at_ratio();
616 }
617 set_start_time(nanos_to_millis(os::javaTimeNanos()));
618 }
619
620
621 #ifdef ASSERT
622 bool CompilationPolicy::verify_level(CompLevel level) {
623 if (TieredCompilation && level > TieredStopAtLevel) {
624 return false;
625 }
626 // Check if there is a compiler to process the requested level
627 if (!CompilerConfig::is_c1_enabled() && is_c1_compile(level)) {
628 return false;
629 }
630 if (!CompilerConfig::is_c2_or_jvmci_compiler_enabled() && is_c2_compile(level)) {
631 return false;
632 }
633
634 // Interpreter level is always valid.
635 if (level == CompLevel_none) {
636 return true;
733 }
734 }
735
736 // Called with the queue locked and with at least one element
737 CompileTask* CompilationPolicy::select_task(CompileQueue* compile_queue, JavaThread* THREAD) {
738 CompileTask *max_blocking_task = nullptr;
739 CompileTask *max_task = nullptr;
740 Method* max_method = nullptr;
741
742 int64_t t = nanos_to_millis(os::javaTimeNanos());
743 // Iterate through the queue and find a method with a maximum rate.
744 for (CompileTask* task = compile_queue->first(); task != nullptr;) {
745 CompileTask* next_task = task->next();
746 // If a method was unloaded or has been stale for some time, remove it from the queue.
747 // Blocking tasks and tasks submitted from whitebox API don't become stale
748 if (task->is_unloaded()) {
749 compile_queue->remove_and_mark_stale(task);
750 task = next_task;
751 continue;
752 }
753 if (task->is_blocking() && task->compile_reason() == CompileTask::Reason_Whitebox) {
754 // CTW tasks, submitted as blocking Whitebox requests, do not participate in rate
755 // selection and/or any level adjustments. Just return them in order.
756 return task;
757 }
758 Method* method = task->method();
759 methodHandle mh(THREAD, method);
760 if (task->can_become_stale() && is_stale(t, TieredCompileTaskTimeout, mh) && !is_old(mh)) {
761 if (PrintTieredEvents) {
762 print_event(REMOVE_FROM_QUEUE, method, method, task->osr_bci(), (CompLevel) task->comp_level());
763 }
764 method->clear_queued_for_compilation();
765 compile_queue->remove_and_mark_stale(task);
766 task = next_task;
767 continue;
768 }
769 update_rate(t, mh);
770 if (max_task == nullptr || compare_methods(method, max_method)) {
771 // Select a method with the highest rate
772 max_task = task;
773 max_method = method;
774 }
775
776 if (task->is_blocking()) {
777 if (max_blocking_task == nullptr || compare_methods(method, max_blocking_task->method())) {
778 max_blocking_task = task;
779 }
780 }
781
782 task = next_task;
783 }
784
785 if (max_blocking_task != nullptr) {
786 // In blocking compilation mode, the CompileBroker will make
787 // compilations submitted by a JVMCI compiler thread non-blocking. These
788 // compilations should be scheduled after all blocking compilations
789 // to service non-compiler related compilations sooner and reduce the
790 // chance of such compilations timing out.
791 max_task = max_blocking_task;
792 max_method = max_task->method();
793 }
794
795 methodHandle max_method_h(THREAD, max_method);
796
797 if (max_task != nullptr && max_task->comp_level() == CompLevel_full_profile && TieredStopAtLevel > CompLevel_full_profile &&
798 max_method != nullptr && is_method_profiled(max_method_h) && !Arguments::is_compiler_only()) {
799 max_task->set_comp_level(CompLevel_limited_profile);
800
801 if (CompileBroker::compilation_is_complete(max_method_h, max_task->osr_bci(), CompLevel_limited_profile)) {
802 if (PrintTieredEvents) {
803 print_event(REMOVE_FROM_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level());
804 }
805 compile_queue->remove_and_mark_stale(max_task);
806 max_method->clear_queued_for_compilation();
807 return nullptr;
808 }
809
810 if (PrintTieredEvents) {
811 print_event(UPDATE_IN_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level());
812 }
813 }
814 return max_task;
815 }
816
817 void CompilationPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) {
818 for (ScopeDesc* sd = trap_scope;; sd = sd->sender()) {
819 if (PrintTieredEvents) {
820 print_event(REPROFILE, sd->method(), sd->method(), InvocationEntryBci, CompLevel_none);
821 }
822 MethodData* mdo = sd->method()->method_data();
823 if (mdo != nullptr) {
824 mdo->reset_start_counters();
825 }
826 if (sd->is_top()) break;
827 }
828 }
829
830 nmethod* CompilationPolicy::event(const methodHandle& method, const methodHandle& inlinee,
831 int branch_bci, int bci, CompLevel comp_level, nmethod* nm, TRAPS) {
832 if (PrintTieredEvents) {
833 print_event(bci == InvocationEntryBci ? CALL : LOOP, method(), inlinee(), bci, comp_level);
918 if (level == CompLevel_full_optimization && can_be_osr_compiled(mh, CompLevel_simple)) {
919 nmethod* osr_nm = mh->lookup_osr_nmethod_for(bci, CompLevel_simple, false);
920 if (osr_nm != nullptr && osr_nm->comp_level() > CompLevel_simple) {
921 // Invalidate the existing OSR nmethod so that a compile at CompLevel_simple is permitted.
922 osr_nm->make_not_entrant("OSR invalidation for compiling with C1");
923 }
924 compile(mh, bci, CompLevel_simple, THREAD);
925 }
926 return;
927 }
928 }
929 if (bci != InvocationEntryBci && mh->is_not_osr_compilable(level)) {
930 return;
931 }
932 if (!CompileBroker::compilation_is_in_queue(mh)) {
933 if (PrintTieredEvents) {
934 print_event(COMPILE, mh(), mh(), bci, level);
935 }
936 int hot_count = (bci == InvocationEntryBci) ? mh->invocation_count() : mh->backedge_count();
937 update_rate(nanos_to_millis(os::javaTimeNanos()), mh);
938 CompileBroker::compile_method(mh, bci, level, hot_count, CompileTask::Reason_Tiered, THREAD);
939 }
940 }
941
942 // update_rate() is called from select_task() while holding a compile queue lock.
943 void CompilationPolicy::update_rate(int64_t t, const methodHandle& method) {
944 // Skip update if counters are absent.
945 // Can't allocate them since we are holding compile queue lock.
946 if (method->method_counters() == nullptr) return;
947
948 if (is_old(method)) {
949 // We don't remove old methods from the queue,
950 // so we can just zero the rate.
951 method->set_rate(0);
952 return;
953 }
954
955 // We don't update the rate if we've just came out of a safepoint.
956 // delta_s is the time since last safepoint in milliseconds.
957 int64_t delta_s = t - SafepointTracing::end_of_last_safepoint_ms();
958 int64_t delta_t = t - (method->prev_time() != 0 ? method->prev_time() : start_time()); // milliseconds since the last measurement
1001 }
1002
1003 double CompilationPolicy::weight(Method* method) {
1004 return (double)(method->rate() + 1) * (method->invocation_count() + 1) * (method->backedge_count() + 1);
1005 }
1006
1007 // Apply heuristics and return true if x should be compiled before y
1008 bool CompilationPolicy::compare_methods(Method* x, Method* y) {
1009 if (x->highest_comp_level() > y->highest_comp_level()) {
1010 // recompilation after deopt
1011 return true;
1012 } else
1013 if (x->highest_comp_level() == y->highest_comp_level()) {
1014 if (weight(x) > weight(y)) {
1015 return true;
1016 }
1017 }
1018 return false;
1019 }
1020
1021 // Is method profiled enough?
1022 bool CompilationPolicy::is_method_profiled(const methodHandle& method) {
1023 MethodData* mdo = method->method_data();
1024 if (mdo != nullptr) {
1025 int i = mdo->invocation_count_delta();
1026 int b = mdo->backedge_count_delta();
1027 return CallPredicate::apply_scaled(method, CompLevel_full_profile, i, b, 1);
1028 }
1029 return false;
1030 }
1031
1032
1033 // Determine is a method is mature.
1034 bool CompilationPolicy::is_mature(MethodData* mdo) {
1035 if (Arguments::is_compiler_only()) {
1036 // Always report profiles as immature with -Xcomp
1037 return false;
1038 }
1039 methodHandle mh(Thread::current(), mdo->method());
1040 if (mdo != nullptr) {
1047 }
1048
1049 // If a method is old enough and is still in the interpreter we would want to
1050 // start profiling without waiting for the compiled method to arrive.
1051 // We also take the load on compilers into the account.
1052 bool CompilationPolicy::should_create_mdo(const methodHandle& method, CompLevel cur_level) {
1053 if (cur_level != CompLevel_none || force_comp_at_level_simple(method) || CompilationModeFlag::quick_only() || !ProfileInterpreter) {
1054 return false;
1055 }
1056
1057 if (TrainingData::have_data()) {
1058 MethodTrainingData* mtd = MethodTrainingData::find_fast(method);
1059 if (mtd != nullptr && mtd->saw_level(CompLevel_full_optimization)) {
1060 return true;
1061 }
1062 }
1063
1064 if (is_old(method)) {
1065 return true;
1066 }
1067
1068 int i = method->invocation_count();
1069 int b = method->backedge_count();
1070 double k = Tier0ProfilingStartPercentage / 100.0;
1071
1072 // If the top level compiler is not keeping up, delay profiling.
1073 if (CompileBroker::queue_size(CompLevel_full_optimization) <= Tier0Delay * compiler_count(CompLevel_full_optimization)) {
1074 return CallPredicate::apply_scaled(method, CompLevel_none, i, b, k) || LoopPredicate::apply_scaled(method, CompLevel_none, i, b, k);
1075 }
1076 return false;
1077 }
1078
1079 // Inlining control: if we're compiling a profiled method with C1 and the callee
1080 // is known to have OSRed in a C2 version, don't inline it.
1081 bool CompilationPolicy::should_not_inline(ciEnv* env, ciMethod* callee) {
1082 CompLevel comp_level = (CompLevel)env->comp_level();
1083 if (comp_level == CompLevel_full_profile ||
1084 comp_level == CompLevel_limited_profile) {
1085 return callee->highest_osr_comp_level() == CompLevel_full_optimization;
1086 }
1087 return false;
|
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotLinkedClassBulkLoader.hpp"
26 #include "code/aotCodeCache.hpp"
27 #include "code/scopeDesc.hpp"
28 #include "compiler/compilationPolicy.hpp"
29 #include "compiler/compileBroker.hpp"
30 #include "compiler/compilerDefinitions.inline.hpp"
31 #include "compiler/compilerOracle.hpp"
32 #include "compiler/recompilationPolicy.hpp"
33 #include "memory/resourceArea.hpp"
34 #include "oops/method.inline.hpp"
35 #include "oops/methodData.hpp"
36 #include "oops/oop.inline.hpp"
37 #include "oops/trainingData.hpp"
38 #include "prims/jvmtiExport.hpp"
39 #include "runtime/arguments.hpp"
40 #include "runtime/deoptimization.hpp"
41 #include "runtime/frame.hpp"
42 #include "runtime/frame.inline.hpp"
43 #include "runtime/globals_extension.hpp"
44 #include "runtime/handles.inline.hpp"
45 #include "runtime/safepoint.hpp"
46 #include "runtime/safepointVerifiers.hpp"
47 #ifdef COMPILER1
48 #include "c1/c1_Compiler.hpp"
49 #endif
50 #ifdef COMPILER2
51 #include "opto/c2compiler.hpp"
52 #endif
53 #if INCLUDE_JVMCI
54 #include "jvmci/jvmci.hpp"
55 #endif
56
57 int64_t CompilationPolicy::_start_time = 0;
58 int CompilationPolicy::_c1_count = 0;
59 int CompilationPolicy::_c2_count = 0;
60 int CompilationPolicy::_ac_count = 0;
61 double CompilationPolicy::_increase_threshold_at_ratio = 0;
62
63 CompilationPolicy::TrainingReplayQueue CompilationPolicy::_training_replay_queue;
64
65 void compilationPolicy_init() {
66 CompilationPolicy::initialize();
67 }
68
69 int CompilationPolicy::compiler_count(CompLevel comp_level) {
70 if (is_c1_compile(comp_level)) {
71 return c1_count();
72 } else if (is_c2_compile(comp_level)) {
73 return c2_count();
74 }
75 return 0;
76 }
77
78 // Returns true if m must be compiled before executing it
79 // This is intended to force compiles for methods (usually for
80 // debugging) that would otherwise be interpreted for some reason.
81 bool CompilationPolicy::must_be_compiled(const methodHandle& m, int comp_level) {
82 // Don't allow Xcomp to cause compiles in replay mode
83 if (ReplayCompiles) return false;
84
85 if (m->has_compiled_code()) return false; // already compiled
86 if (!can_be_compiled(m, comp_level)) return false;
87
88 return !UseInterpreter || // must compile all methods
89 (AlwaysCompileLoopMethods && m->has_loops() && CompileBroker::should_compile_new_jobs()); // eagerly compile loop methods
90 }
91
92 void CompilationPolicy::maybe_compile_early(const methodHandle& m, TRAPS) {
93 if (m->method_holder()->is_not_initialized()) {
94 // 'is_not_initialized' means not only '!is_initialized', but also that
95 // initialization has not been started yet ('!being_initialized')
96 // Do not force compilation of methods in uninitialized classes.
97 return;
98 }
99 if (!m->is_native() && MethodTrainingData::have_data()) {
100 MethodTrainingData* mtd = MethodTrainingData::find_fast(m);
101 if (mtd == nullptr) {
102 return; // there is no training data recorded for m
103 }
104 // AOT Preload code with class init barriers is used,
105 // consider replacing it with normal (faster) AOT code
106 bool recompile = m->code_has_clinit_barriers();
107 CompLevel cur_level = static_cast<CompLevel>(m->highest_comp_level());
108 CompLevel next_level = trained_transition(m, cur_level, mtd, THREAD);
109 if ((next_level != cur_level || recompile) && can_be_compiled(m, next_level) && !CompileBroker::compilation_is_in_queue(m)) {
110 bool requires_online_compilation = false;
111 CompileTrainingData* ctd = mtd->last_toplevel_compile(next_level);
112 if (ctd != nullptr) {
113 // Can't load normal AOT code - not all dependancies are ready,
114 // request normal compilation
115 requires_online_compilation = (ctd->init_deps_left() > 0);
116 }
117 if (requires_online_compilation && recompile) {
118 // Wait when dependencies are ready to load normal AOT code
119 // if AOT Preload code is used now.
120 //
121 // FIXME. We may never (or it take long time) get all dependencies
122 // be ready to replace AOT Preload code. Consider using time and how many
123 // dependencies left to allow normal JIT compilation for replacement.
124 return;
125 }
126 if (PrintTieredEvents) {
127 print_event(FORCE_COMPILE, m(), m(), InvocationEntryBci, next_level);
128 }
129 CompileBroker::compile_method(m, InvocationEntryBci, next_level, 0, requires_online_compilation, CompileTask::Reason_MustBeCompiled, THREAD);
130 if (HAS_PENDING_EXCEPTION) {
131 CLEAR_PENDING_EXCEPTION;
132 }
133 }
134 }
135 }
136
137 void CompilationPolicy::maybe_compile_early_after_init(const methodHandle& m, TRAPS) {
138 assert(m->method_holder()->is_initialized(), "Should be called after class initialization");
139 maybe_compile_early(m, THREAD);
140 }
141
142 void CompilationPolicy::compile_if_required(const methodHandle& m, TRAPS) {
143 if (!THREAD->can_call_java() || THREAD->is_Compiler_thread()) {
144 // don't force compilation, resolve was on behalf of compiler
145 return;
146 }
147 if (m->method_holder()->is_not_initialized()) {
148 // 'is_not_initialized' means not only '!is_initialized', but also that
149 // initialization has not been started yet ('!being_initialized')
150 // Do not force compilation of methods in uninitialized classes.
151 // Note that doing this would throw an assert later,
152 // in CompileBroker::compile_method.
153 // We sometimes use the link resolver to do reflective lookups
154 // even before classes are initialized.
155 return;
156 }
157
158 if (must_be_compiled(m)) {
159 // This path is unusual, mostly used by the '-Xcomp' stress test mode.
160 CompLevel level = initial_compile_level(m);
161 if (PrintTieredEvents) {
162 print_event(FORCE_COMPILE, m(), m(), InvocationEntryBci, level);
163 }
164 // Test AOT code too
165 bool requires_online_compilation = false;
166 if (TrainingData::have_data()) {
167 MethodTrainingData* mtd = MethodTrainingData::find_fast(m);
168 if (mtd != nullptr) {
169 CompileTrainingData* ctd = mtd->last_toplevel_compile(level);
170 if (ctd != nullptr) {
171 requires_online_compilation = (ctd->init_deps_left() > 0);
172 }
173 }
174 }
175 CompileBroker::compile_method(m, InvocationEntryBci, level, 0, requires_online_compilation, CompileTask::Reason_MustBeCompiled, THREAD);
176 }
177 }
178
179 void CompilationPolicy::replay_training_at_init_impl(InstanceKlass* klass, TRAPS) {
180 if (!klass->has_init_deps_processed()) {
181 ResourceMark rm;
182 log_debug(training)("Replay training: %s", klass->external_name());
183
184 KlassTrainingData* ktd = KlassTrainingData::find(klass);
185 if (ktd != nullptr) {
186 guarantee(ktd->has_holder(), "");
187 ktd->notice_fully_initialized(); // sets klass->has_init_deps_processed bit
188 assert(klass->has_init_deps_processed(), "");
189
190 if (AOTCompileEagerly) {
191 ktd->iterate_comp_deps([&](CompileTrainingData* ctd) {
192 if (ctd->init_deps_left() == 0) {
193 MethodTrainingData* mtd = ctd->method();
194 if (mtd->has_holder()) {
195 const methodHandle mh(THREAD, const_cast<Method*>(mtd->holder()));
196 CompilationPolicy::maybe_compile_early(mh, THREAD);
197 }
198 }
199 });
200 }
201 }
202 }
203 }
204
205 void CompilationPolicy::flush_replay_training_at_init(TRAPS) {
206 MonitorLocker locker(THREAD, TrainingReplayQueue_lock);
207 while (!_training_replay_queue.is_empty_unlocked()) {
208 locker.wait(); // let the replay training thread drain the queue
209 }
210 }
211
212 void CompilationPolicy::replay_training_at_init(InstanceKlass* klass, TRAPS) {
213 assert(klass->is_initialized(), "");
214 if (TrainingData::have_data() && klass->is_shared()) {
215 _training_replay_queue.push(klass, TrainingReplayQueue_lock, THREAD);
216 }
217 }
218
219 // For TrainingReplayQueue
220 template<>
221 void CompilationPolicyUtils::Queue<InstanceKlass>::print_on(outputStream* st) {
222 int pos = 0;
223 for (QueueNode* cur = _head; cur != nullptr; cur = cur->next()) {
224 ResourceMark rm;
225 InstanceKlass* ik = cur->value();
226 st->print_cr("%3d: " INTPTR_FORMAT " %s", ++pos, p2i(ik), ik->external_name());
227 }
228 }
229
230 void CompilationPolicy::replay_training_at_init_loop(TRAPS) {
231 while (!CompileBroker::is_compilation_disabled_forever() || AOTVerifyTrainingData) {
232 InstanceKlass* ik = _training_replay_queue.pop(TrainingReplayQueue_lock, THREAD);
233 if (ik != nullptr) {
234 replay_training_at_init_impl(ik, THREAD);
235 }
236 }
237 }
238
239 static inline CompLevel adjust_level_for_compilability_query(CompLevel comp_level) {
240 if (comp_level == CompLevel_any) {
241 if (CompilerConfig::is_c1_only()) {
242 comp_level = CompLevel_simple;
243 } else if (CompilerConfig::is_c2_or_jvmci_compiler_only()) {
244 comp_level = CompLevel_full_optimization;
245 }
246 }
247 return comp_level;
248 }
249
250 // Returns true if m is allowed to be compiled
251 bool CompilationPolicy::can_be_compiled(const methodHandle& m, int comp_level) {
501 // Print an event.
502 void CompilationPolicy::print_event(EventType type, Method* m, Method* im, int bci, CompLevel level) {
503 bool inlinee_event = m != im;
504
505 ttyLocker tty_lock;
506 tty->print("%lf: [", os::elapsedTime());
507
508 switch(type) {
509 case CALL:
510 tty->print("call");
511 break;
512 case LOOP:
513 tty->print("loop");
514 break;
515 case COMPILE:
516 tty->print("compile");
517 break;
518 case FORCE_COMPILE:
519 tty->print("force-compile");
520 break;
521 case FORCE_RECOMPILE:
522 tty->print("force-recompile");
523 break;
524 case REMOVE_FROM_QUEUE:
525 tty->print("remove-from-queue");
526 break;
527 case UPDATE_IN_QUEUE:
528 tty->print("update-in-queue");
529 break;
530 case REPROFILE:
531 tty->print("reprofile");
532 break;
533 case MAKE_NOT_ENTRANT:
534 tty->print("make-not-entrant");
535 break;
536 default:
537 tty->print("unknown");
538 }
539
540 tty->print(" level=%d ", level);
541
542 ResourceMark rm;
543 char *method_name = m->name_and_sig_as_C_string();
544 tty->print("[%s", method_name);
545 if (inlinee_event) {
546 char *inlinee_name = im->name_and_sig_as_C_string();
547 tty->print(" [%s]] ", inlinee_name);
548 }
549 else tty->print("] ");
550 tty->print("@%d queues=%d,%d", bci, CompileBroker::queue_size(CompLevel_full_profile),
551 CompileBroker::queue_size(CompLevel_full_optimization));
552
553 tty->print(" rate=");
554 if (m->prev_time() == 0) tty->print("n/a");
555 else tty->print("%f", m->rate());
556
557 RecompilationPolicy::print_load_average();
558
559 tty->print(" k=%.2lf,%.2lf", threshold_scale(CompLevel_full_profile, Tier3LoadFeedback),
560 threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback));
561
562 if (type != COMPILE) {
563 print_counters("", m);
564 if (inlinee_event) {
565 print_counters("inlinee ", im);
566 }
567 tty->print(" compilable=");
568 bool need_comma = false;
569 if (!m->is_not_compilable(CompLevel_full_profile)) {
570 tty->print("c1");
571 need_comma = true;
572 }
573 if (!m->is_not_osr_compilable(CompLevel_full_profile)) {
574 if (need_comma) tty->print(",");
575 tty->print("c1-osr");
576 need_comma = true;
577 }
578 if (!m->is_not_compilable(CompLevel_full_optimization)) {
587 tty->print(" status=");
588 if (m->queued_for_compilation()) {
589 tty->print("in-queue");
590 } else tty->print("idle");
591 print_training_data("", m);
592 if (inlinee_event) {
593 print_training_data("inlinee ", im);
594 }
595 }
596 tty->print_cr("]");
597 }
598
599 void CompilationPolicy::initialize() {
600 if (!CompilerConfig::is_interpreter_only()) {
601 int count = CICompilerCount;
602 bool c1_only = CompilerConfig::is_c1_only();
603 bool c2_only = CompilerConfig::is_c2_or_jvmci_compiler_only();
604
605 #ifdef _LP64
606 // Turn on ergonomic compiler count selection
607 if (AOTCodeCache::maybe_dumping_code()) {
608 // Assembly phase runs C1 and C2 compilation in separate phases,
609 // and can use all the CPU threads it can reach. Adjust the common
610 // options before policy starts overwriting them.
611 FLAG_SET_ERGO_IF_DEFAULT(UseDynamicNumberOfCompilerThreads, false);
612 FLAG_SET_ERGO_IF_DEFAULT(CICompilerCountPerCPU, false);
613 if (FLAG_IS_DEFAULT(CICompilerCount)) {
614 count = MAX2(count, os::active_processor_count());
615 }
616 }
617 if (FLAG_IS_DEFAULT(CICompilerCountPerCPU) && FLAG_IS_DEFAULT(CICompilerCount)) {
618 FLAG_SET_DEFAULT(CICompilerCountPerCPU, true);
619 }
620 if (CICompilerCountPerCPU) {
621 // Simple log n seems to grow too slowly for tiered, try something faster: log n * log log n
622 int log_cpu = log2i(os::active_processor_count());
623 int loglog_cpu = log2i(MAX2(log_cpu, 1));
624 count = MAX2(log_cpu * loglog_cpu * 3 / 2, 2);
625 }
626 if (FLAG_IS_DEFAULT(CICompilerCount)) {
627 // Make sure there is enough space in the code cache to hold all the compiler buffers
628 size_t c1_size = 0;
629 #ifdef COMPILER1
630 c1_size = Compiler::code_buffer_size();
631 #endif
632 size_t c2_size = 0;
633 #ifdef COMPILER2
634 c2_size = C2Compiler::initial_code_buffer_size();
635 #endif
636 size_t buffer_size = c1_only ? c1_size : (c1_size/3 + 2*c2_size/3);
637 int max_count = (ReservedCodeCacheSize - (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3))) / (int)buffer_size;
638 if (count > max_count) {
639 // Lower the compiler count such that all buffers fit into the code cache
640 count = MAX2(max_count, c1_only ? 1 : 2);
641 }
642 FLAG_SET_ERGO(CICompilerCount, count);
643 }
644 #else
645 // On 32-bit systems, the number of compiler threads is limited to 3.
646 // On these systems, the virtual address space available to the JVM
657
658 if (c1_only) {
659 // No C2 compiler thread required
660 set_c1_count(count);
661 } else if (c2_only) {
662 set_c2_count(count);
663 } else {
664 #if INCLUDE_JVMCI
665 if (UseJVMCICompiler && UseJVMCINativeLibrary) {
666 int libjvmci_count = MAX2((int) (count * JVMCINativeLibraryThreadFraction), 1);
667 int c1_count = MAX2(count - libjvmci_count, 1);
668 set_c2_count(libjvmci_count);
669 set_c1_count(c1_count);
670 } else
671 #endif
672 {
673 set_c1_count(MAX2(count / 3, 1));
674 set_c2_count(MAX2(count - c1_count(), 1));
675 }
676 }
677 if (AOTCodeCache::is_code_load_thread_on()) {
678 set_ac_count((c1_only || c2_only) ? 1 : 2); // At minimum we need 2 threads to load C1 and C2 AOT code in parallel
679 }
680 assert(count == c1_count() + c2_count(), "inconsistent compiler thread count");
681 set_increase_threshold_at_ratio();
682 }
683
684 set_start_time(nanos_to_millis(os::javaTimeNanos()));
685 }
686
687
688 #ifdef ASSERT
689 bool CompilationPolicy::verify_level(CompLevel level) {
690 if (TieredCompilation && level > TieredStopAtLevel) {
691 return false;
692 }
693 // Check if there is a compiler to process the requested level
694 if (!CompilerConfig::is_c1_enabled() && is_c1_compile(level)) {
695 return false;
696 }
697 if (!CompilerConfig::is_c2_or_jvmci_compiler_enabled() && is_c2_compile(level)) {
698 return false;
699 }
700
701 // Interpreter level is always valid.
702 if (level == CompLevel_none) {
703 return true;
800 }
801 }
802
803 // Called with the queue locked and with at least one element
804 CompileTask* CompilationPolicy::select_task(CompileQueue* compile_queue, JavaThread* THREAD) {
805 CompileTask *max_blocking_task = nullptr;
806 CompileTask *max_task = nullptr;
807 Method* max_method = nullptr;
808
809 int64_t t = nanos_to_millis(os::javaTimeNanos());
810 // Iterate through the queue and find a method with a maximum rate.
811 for (CompileTask* task = compile_queue->first(); task != nullptr;) {
812 CompileTask* next_task = task->next();
813 // If a method was unloaded or has been stale for some time, remove it from the queue.
814 // Blocking tasks and tasks submitted from whitebox API don't become stale
815 if (task->is_unloaded()) {
816 compile_queue->remove_and_mark_stale(task);
817 task = next_task;
818 continue;
819 }
820 if (task->is_aot_load()) {
821 // AOTCodeCache tasks are on separate queue, and they should load fast. There is no need to walk
822 // the rest of the queue, just take the task and go.
823 return task;
824 }
825 if (task->is_blocking() && task->compile_reason() == CompileTask::Reason_Whitebox) {
826 // CTW tasks, submitted as blocking Whitebox requests, do not participate in rate
827 // selection and/or any level adjustments. Just return them in order.
828 return task;
829 }
830 Method* method = task->method();
831 methodHandle mh(THREAD, method);
832 if (task->can_become_stale() && is_stale(t, TieredCompileTaskTimeout, mh) && !is_old(mh)) {
833 if (PrintTieredEvents) {
834 print_event(REMOVE_FROM_QUEUE, method, method, task->osr_bci(), (CompLevel) task->comp_level());
835 }
836 method->clear_queued_for_compilation();
837 method->set_pending_queue_processed(false);
838 compile_queue->remove_and_mark_stale(task);
839 task = next_task;
840 continue;
841 }
842 update_rate(t, mh);
843 if (max_task == nullptr || compare_methods(method, max_method) || compare_tasks(task, max_task)) {
844 // Select a method with the highest rate
845 max_task = task;
846 max_method = method;
847 }
848
849 if (task->is_blocking()) {
850 if (max_blocking_task == nullptr || compare_methods(method, max_blocking_task->method())) {
851 max_blocking_task = task;
852 }
853 }
854
855 task = next_task;
856 }
857
858 if (max_blocking_task != nullptr) {
859 // In blocking compilation mode, the CompileBroker will make
860 // compilations submitted by a JVMCI compiler thread non-blocking. These
861 // compilations should be scheduled after all blocking compilations
862 // to service non-compiler related compilations sooner and reduce the
863 // chance of such compilations timing out.
864 max_task = max_blocking_task;
865 max_method = max_task->method();
866 }
867
868 methodHandle max_method_h(THREAD, max_method);
869
870 if (max_task != nullptr && max_task->comp_level() == CompLevel_full_profile && TieredStopAtLevel > CompLevel_full_profile &&
871 max_method != nullptr && is_method_profiled(max_method_h) && !Arguments::is_compiler_only()) {
872 max_task->set_comp_level(CompLevel_limited_profile);
873
874 if (CompileBroker::compilation_is_complete(max_method_h(), max_task->osr_bci(), CompLevel_limited_profile,
875 false /* requires_online_compilation */,
876 CompileTask::Reason_None)) {
877 if (PrintTieredEvents) {
878 print_event(REMOVE_FROM_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level());
879 }
880 compile_queue->remove_and_mark_stale(max_task);
881 max_method->clear_queued_for_compilation();
882 return nullptr;
883 }
884
885 if (PrintTieredEvents) {
886 print_event(UPDATE_IN_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level());
887 }
888 }
889
890 return max_task;
891 }
892
893 void CompilationPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) {
894 for (ScopeDesc* sd = trap_scope;; sd = sd->sender()) {
895 if (PrintTieredEvents) {
896 print_event(REPROFILE, sd->method(), sd->method(), InvocationEntryBci, CompLevel_none);
897 }
898 MethodData* mdo = sd->method()->method_data();
899 if (mdo != nullptr) {
900 mdo->reset_start_counters();
901 }
902 if (sd->is_top()) break;
903 }
904 }
905
906 nmethod* CompilationPolicy::event(const methodHandle& method, const methodHandle& inlinee,
907 int branch_bci, int bci, CompLevel comp_level, nmethod* nm, TRAPS) {
908 if (PrintTieredEvents) {
909 print_event(bci == InvocationEntryBci ? CALL : LOOP, method(), inlinee(), bci, comp_level);
994 if (level == CompLevel_full_optimization && can_be_osr_compiled(mh, CompLevel_simple)) {
995 nmethod* osr_nm = mh->lookup_osr_nmethod_for(bci, CompLevel_simple, false);
996 if (osr_nm != nullptr && osr_nm->comp_level() > CompLevel_simple) {
997 // Invalidate the existing OSR nmethod so that a compile at CompLevel_simple is permitted.
998 osr_nm->make_not_entrant("OSR invalidation for compiling with C1");
999 }
1000 compile(mh, bci, CompLevel_simple, THREAD);
1001 }
1002 return;
1003 }
1004 }
1005 if (bci != InvocationEntryBci && mh->is_not_osr_compilable(level)) {
1006 return;
1007 }
1008 if (!CompileBroker::compilation_is_in_queue(mh)) {
1009 if (PrintTieredEvents) {
1010 print_event(COMPILE, mh(), mh(), bci, level);
1011 }
1012 int hot_count = (bci == InvocationEntryBci) ? mh->invocation_count() : mh->backedge_count();
1013 update_rate(nanos_to_millis(os::javaTimeNanos()), mh);
1014 bool requires_online_compilation = false;
1015 if (TrainingData::have_data()) {
1016 MethodTrainingData* mtd = MethodTrainingData::find_fast(mh);
1017 if (mtd != nullptr) {
1018 CompileTrainingData* ctd = mtd->last_toplevel_compile(level);
1019 if (ctd != nullptr) {
1020 requires_online_compilation = (ctd->init_deps_left() > 0);
1021 }
1022 }
1023 }
1024 CompileBroker::compile_method(mh, bci, level, hot_count, requires_online_compilation, CompileTask::Reason_Tiered, THREAD);
1025 }
1026 }
1027
1028 // update_rate() is called from select_task() while holding a compile queue lock.
1029 void CompilationPolicy::update_rate(int64_t t, const methodHandle& method) {
1030 // Skip update if counters are absent.
1031 // Can't allocate them since we are holding compile queue lock.
1032 if (method->method_counters() == nullptr) return;
1033
1034 if (is_old(method)) {
1035 // We don't remove old methods from the queue,
1036 // so we can just zero the rate.
1037 method->set_rate(0);
1038 return;
1039 }
1040
1041 // We don't update the rate if we've just came out of a safepoint.
1042 // delta_s is the time since last safepoint in milliseconds.
1043 int64_t delta_s = t - SafepointTracing::end_of_last_safepoint_ms();
1044 int64_t delta_t = t - (method->prev_time() != 0 ? method->prev_time() : start_time()); // milliseconds since the last measurement
1087 }
1088
1089 double CompilationPolicy::weight(Method* method) {
1090 return (double)(method->rate() + 1) * (method->invocation_count() + 1) * (method->backedge_count() + 1);
1091 }
1092
1093 // Apply heuristics and return true if x should be compiled before y
1094 bool CompilationPolicy::compare_methods(Method* x, Method* y) {
1095 if (x->highest_comp_level() > y->highest_comp_level()) {
1096 // recompilation after deopt
1097 return true;
1098 } else
1099 if (x->highest_comp_level() == y->highest_comp_level()) {
1100 if (weight(x) > weight(y)) {
1101 return true;
1102 }
1103 }
1104 return false;
1105 }
1106
1107 bool CompilationPolicy::compare_tasks(CompileTask* x, CompileTask* y) {
1108 assert(!x->is_aot_load() && !y->is_aot_load(), "AOT code caching tasks are not expected here");
1109 if (x->compile_reason() != y->compile_reason() && y->compile_reason() == CompileTask::Reason_MustBeCompiled) {
1110 return true;
1111 }
1112 return false;
1113 }
1114
1115 // Is method profiled enough?
1116 bool CompilationPolicy::is_method_profiled(const methodHandle& method) {
1117 MethodData* mdo = method->method_data();
1118 if (mdo != nullptr) {
1119 int i = mdo->invocation_count_delta();
1120 int b = mdo->backedge_count_delta();
1121 return CallPredicate::apply_scaled(method, CompLevel_full_profile, i, b, 1);
1122 }
1123 return false;
1124 }
1125
1126
1127 // Determine is a method is mature.
1128 bool CompilationPolicy::is_mature(MethodData* mdo) {
1129 if (Arguments::is_compiler_only()) {
1130 // Always report profiles as immature with -Xcomp
1131 return false;
1132 }
1133 methodHandle mh(Thread::current(), mdo->method());
1134 if (mdo != nullptr) {
1141 }
1142
1143 // If a method is old enough and is still in the interpreter we would want to
1144 // start profiling without waiting for the compiled method to arrive.
1145 // We also take the load on compilers into the account.
1146 bool CompilationPolicy::should_create_mdo(const methodHandle& method, CompLevel cur_level) {
1147 if (cur_level != CompLevel_none || force_comp_at_level_simple(method) || CompilationModeFlag::quick_only() || !ProfileInterpreter) {
1148 return false;
1149 }
1150
1151 if (TrainingData::have_data()) {
1152 MethodTrainingData* mtd = MethodTrainingData::find_fast(method);
1153 if (mtd != nullptr && mtd->saw_level(CompLevel_full_optimization)) {
1154 return true;
1155 }
1156 }
1157
1158 if (is_old(method)) {
1159 return true;
1160 }
1161 int i = method->invocation_count();
1162 int b = method->backedge_count();
1163 double k = Tier0ProfilingStartPercentage / 100.0;
1164
1165 // If the top level compiler is not keeping up, delay profiling.
1166 if (CompileBroker::queue_size(CompLevel_full_optimization) <= Tier0Delay * compiler_count(CompLevel_full_optimization)) {
1167 return CallPredicate::apply_scaled(method, CompLevel_none, i, b, k) || LoopPredicate::apply_scaled(method, CompLevel_none, i, b, k);
1168 }
1169 return false;
1170 }
1171
1172 // Inlining control: if we're compiling a profiled method with C1 and the callee
1173 // is known to have OSRed in a C2 version, don't inline it.
1174 bool CompilationPolicy::should_not_inline(ciEnv* env, ciMethod* callee) {
1175 CompLevel comp_level = (CompLevel)env->comp_level();
1176 if (comp_level == CompLevel_full_profile ||
1177 comp_level == CompLevel_limited_profile) {
1178 return callee->highest_osr_comp_level() == CompLevel_full_optimization;
1179 }
1180 return false;
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