1 /*
2 * Copyright (c) 2010, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "code/codeCache.hpp"
27 #include "compiler/compileTask.hpp"
28 #include "runtime/advancedThresholdPolicy.hpp"
29 #include "runtime/simpleThresholdPolicy.inline.hpp"
30 #if INCLUDE_JVMCI
31 #include "jvmci/jvmciRuntime.hpp"
32 #endif
33
34 #ifdef TIERED
35 // Print an event.
36 void AdvancedThresholdPolicy::print_specific(EventType type, methodHandle mh, methodHandle imh,
37 int bci, CompLevel level) {
38 tty->print(" rate=");
39 if (mh->prev_time() == 0) tty->print("n/a");
40 else tty->print("%f", mh->rate());
41
42 tty->print(" k=%.2lf,%.2lf", threshold_scale(CompLevel_full_profile, Tier3LoadFeedback),
43 threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback));
44
45 }
46
47 void AdvancedThresholdPolicy::initialize() {
48 int count = CICompilerCount;
49 #ifdef _LP64
50 // Turn on ergonomic compiler count selection
51 if (FLAG_IS_DEFAULT(CICompilerCountPerCPU) && FLAG_IS_DEFAULT(CICompilerCount)) {
52 FLAG_SET_DEFAULT(CICompilerCountPerCPU, true);
53 }
54 if (CICompilerCountPerCPU) {
55 // Simple log n seems to grow too slowly for tiered, try something faster: log n * log log n
56 int log_cpu = log2_intptr(os::active_processor_count());
57 int loglog_cpu = log2_intptr(MAX2(log_cpu, 1));
58 count = MAX2(log_cpu * loglog_cpu, 1) * 3 / 2;
59 }
60 #else
61 // On 32-bit systems, the number of compiler threads is limited to 3.
62 // On these systems, the virtual address space available to the JVM
63 // is usually limited to 2-4 GB (the exact value depends on the platform).
64 // As the compilers (especially C2) can consume a large amount of
65 // memory, scaling the number of compiler threads with the number of
66 // available cores can result in the exhaustion of the address space
67 /// available to the VM and thus cause the VM to crash.
68 if (FLAG_IS_DEFAULT(CICompilerCount)) {
69 count = 3;
70 }
71 #endif
72
73 set_c1_count(MAX2(count / 3, 1));
74 set_c2_count(MAX2(count - c1_count(), 1));
75 FLAG_SET_ERGO(intx, CICompilerCount, c1_count() + c2_count());
76
77 // Some inlining tuning
78 #ifdef X86
79 if (FLAG_IS_DEFAULT(InlineSmallCode)) {
80 FLAG_SET_DEFAULT(InlineSmallCode, 2000);
81 }
82 #endif
83
84 #if defined SPARC || defined AARCH64
85 if (FLAG_IS_DEFAULT(InlineSmallCode)) {
86 FLAG_SET_DEFAULT(InlineSmallCode, 2500);
87 }
88 #endif
89
90 set_increase_threshold_at_ratio();
91 set_start_time(os::javaTimeMillis());
92 }
93
94 // update_rate() is called from select_task() while holding a compile queue lock.
95 void AdvancedThresholdPolicy::update_rate(jlong t, Method* m) {
96 // Skip update if counters are absent.
97 // Can't allocate them since we are holding compile queue lock.
98 if (m->method_counters() == NULL) return;
99
100 if (is_old(m)) {
101 // We don't remove old methods from the queue,
102 // so we can just zero the rate.
103 m->set_rate(0);
104 return;
105 }
106
107 // We don't update the rate if we've just came out of a safepoint.
108 // delta_s is the time since last safepoint in milliseconds.
109 jlong delta_s = t - SafepointSynchronize::end_of_last_safepoint();
110 jlong delta_t = t - (m->prev_time() != 0 ? m->prev_time() : start_time()); // milliseconds since the last measurement
111 // How many events were there since the last time?
112 int event_count = m->invocation_count() + m->backedge_count();
113 int delta_e = event_count - m->prev_event_count();
114
115 // We should be running for at least 1ms.
116 if (delta_s >= TieredRateUpdateMinTime) {
117 // And we must've taken the previous point at least 1ms before.
118 if (delta_t >= TieredRateUpdateMinTime && delta_e > 0) {
119 m->set_prev_time(t);
120 m->set_prev_event_count(event_count);
121 m->set_rate((float)delta_e / (float)delta_t); // Rate is events per millisecond
122 } else {
123 if (delta_t > TieredRateUpdateMaxTime && delta_e == 0) {
124 // If nothing happened for 25ms, zero the rate. Don't modify prev values.
125 m->set_rate(0);
126 }
127 }
128 }
129 }
130
131 // Check if this method has been stale from a given number of milliseconds.
132 // See select_task().
133 bool AdvancedThresholdPolicy::is_stale(jlong t, jlong timeout, Method* m) {
134 jlong delta_s = t - SafepointSynchronize::end_of_last_safepoint();
135 jlong delta_t = t - m->prev_time();
136 if (delta_t > timeout && delta_s > timeout) {
137 int event_count = m->invocation_count() + m->backedge_count();
138 int delta_e = event_count - m->prev_event_count();
139 // Return true if there were no events.
140 return delta_e == 0;
141 }
142 return false;
143 }
144
145 // We don't remove old methods from the compile queue even if they have
146 // very low activity. See select_task().
147 bool AdvancedThresholdPolicy::is_old(Method* method) {
148 return method->invocation_count() > 50000 || method->backedge_count() > 500000;
149 }
150
151 double AdvancedThresholdPolicy::weight(Method* method) {
152 return (double)(method->rate() + 1) *
153 (method->invocation_count() + 1) * (method->backedge_count() + 1);
154 }
155
156 // Apply heuristics and return true if x should be compiled before y
157 bool AdvancedThresholdPolicy::compare_methods(Method* x, Method* y) {
158 if (x->highest_comp_level() > y->highest_comp_level()) {
159 // recompilation after deopt
160 return true;
161 } else
162 if (x->highest_comp_level() == y->highest_comp_level()) {
163 if (weight(x) > weight(y)) {
164 return true;
165 }
166 }
167 return false;
168 }
169
170 // Is method profiled enough?
171 bool AdvancedThresholdPolicy::is_method_profiled(Method* method) {
172 MethodData* mdo = method->method_data();
173 if (mdo != NULL) {
174 int i = mdo->invocation_count_delta();
175 int b = mdo->backedge_count_delta();
176 return call_predicate_helper<CompLevel_full_profile>(i, b, 1, method);
177 }
178 return false;
179 }
180
181 // Called with the queue locked and with at least one element
182 CompileTask* AdvancedThresholdPolicy::select_task(CompileQueue* compile_queue) {
183 CompileTask *max_blocking_task = NULL;
184 CompileTask *max_task = NULL;
185 Method* max_method = NULL;
186 jlong t = os::javaTimeMillis();
187 // Iterate through the queue and find a method with a maximum rate.
188 for (CompileTask* task = compile_queue->first(); task != NULL;) {
189 CompileTask* next_task = task->next();
190 Method* method = task->method();
191 update_rate(t, method);
192 if (max_task == NULL) {
193 max_task = task;
194 max_method = method;
195 } else {
196 // If a method has been stale for some time, remove it from the queue.
197 // Blocking tasks and tasks submitted from whitebox API don't become stale
198 if (task->can_become_stale() && is_stale(t, TieredCompileTaskTimeout, method) && !is_old(method)) {
199 if (PrintTieredEvents) {
200 print_event(REMOVE_FROM_QUEUE, method, method, task->osr_bci(), (CompLevel)task->comp_level());
201 }
202 task->log_task_dequeued("stale");
203 compile_queue->remove_and_mark_stale(task);
204 method->clear_queued_for_compilation();
205 task = next_task;
206 continue;
207 }
208
209 // Select a method with a higher rate
210 if (compare_methods(method, max_method)) {
211 max_task = task;
212 max_method = method;
213 }
214 }
215
216 if (task->is_blocking()) {
217 if (max_blocking_task == NULL || compare_methods(method, max_blocking_task->method())) {
218 max_blocking_task = task;
219 }
220 }
221
222 task = next_task;
223 }
224
225 if (max_blocking_task != NULL) {
226 // In blocking compilation mode, the CompileBroker will make
227 // compilations submitted by a JVMCI compiler thread non-blocking. These
228 // compilations should be scheduled after all blocking compilations
229 // to service non-compiler related compilations sooner and reduce the
230 // chance of such compilations timing out.
231 max_task = max_blocking_task;
232 max_method = max_task->method();
233 }
234
235 if (max_task->comp_level() == CompLevel_full_profile && TieredStopAtLevel > CompLevel_full_profile
236 && is_method_profiled(max_method)) {
237 max_task->set_comp_level(CompLevel_limited_profile);
238 if (PrintTieredEvents) {
239 print_event(UPDATE_IN_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level());
240 }
241 }
242
243 return max_task;
244 }
245
246 double AdvancedThresholdPolicy::threshold_scale(CompLevel level, int feedback_k) {
247 double queue_size = CompileBroker::queue_size(level);
248 int comp_count = compiler_count(level);
249 double k = queue_size / (feedback_k * comp_count) + 1;
250
251 // Increase C1 compile threshold when the code cache is filled more
252 // than specified by IncreaseFirstTierCompileThresholdAt percentage.
253 // The main intention is to keep enough free space for C2 compiled code
254 // to achieve peak performance if the code cache is under stress.
255 if ((TieredStopAtLevel == CompLevel_full_optimization) && (level != CompLevel_full_optimization)) {
256 double current_reverse_free_ratio = CodeCache::reverse_free_ratio(CodeCache::get_code_blob_type(level));
257 if (current_reverse_free_ratio > _increase_threshold_at_ratio) {
258 k *= exp(current_reverse_free_ratio - _increase_threshold_at_ratio);
259 }
260 }
261 return k;
262 }
263
264 // Call and loop predicates determine whether a transition to a higher
265 // compilation level should be performed (pointers to predicate functions
266 // are passed to common()).
267 // Tier?LoadFeedback is basically a coefficient that determines of
268 // how many methods per compiler thread can be in the queue before
269 // the threshold values double.
270 bool AdvancedThresholdPolicy::loop_predicate(int i, int b, CompLevel cur_level, Method* method) {
271 switch(cur_level) {
272 case CompLevel_none:
273 case CompLevel_limited_profile: {
274 double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback);
275 return loop_predicate_helper<CompLevel_none>(i, b, k, method);
276 }
277 case CompLevel_full_profile: {
278 double k = threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback);
279 return loop_predicate_helper<CompLevel_full_profile>(i, b, k, method);
280 }
281 default:
282 return true;
283 }
284 }
285
286 bool AdvancedThresholdPolicy::call_predicate(int i, int b, CompLevel cur_level, Method* method) {
287 switch(cur_level) {
288 case CompLevel_none:
289 case CompLevel_limited_profile: {
290 double k = threshold_scale(CompLevel_full_profile, Tier3LoadFeedback);
291 return call_predicate_helper<CompLevel_none>(i, b, k, method);
292 }
293 case CompLevel_full_profile: {
294 double k = threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback);
295 return call_predicate_helper<CompLevel_full_profile>(i, b, k, method);
296 }
297 default:
298 return true;
299 }
300 }
301
302 // If a method is old enough and is still in the interpreter we would want to
303 // start profiling without waiting for the compiled method to arrive.
304 // We also take the load on compilers into the account.
305 bool AdvancedThresholdPolicy::should_create_mdo(Method* method, CompLevel cur_level) {
306 if (cur_level == CompLevel_none &&
307 CompileBroker::queue_size(CompLevel_full_optimization) <=
308 Tier3DelayOn * compiler_count(CompLevel_full_optimization)) {
309 int i = method->invocation_count();
310 int b = method->backedge_count();
311 double k = Tier0ProfilingStartPercentage / 100.0;
312 return call_predicate_helper<CompLevel_none>(i, b, k, method) || loop_predicate_helper<CompLevel_none>(i, b, k, method);
313 }
314 return false;
315 }
316
317 // Inlining control: if we're compiling a profiled method with C1 and the callee
318 // is known to have OSRed in a C2 version, don't inline it.
319 bool AdvancedThresholdPolicy::should_not_inline(ciEnv* env, ciMethod* callee) {
320 CompLevel comp_level = (CompLevel)env->comp_level();
321 if (comp_level == CompLevel_full_profile ||
322 comp_level == CompLevel_limited_profile) {
323 return callee->highest_osr_comp_level() == CompLevel_full_optimization;
324 }
325 return false;
326 }
327
328 // Create MDO if necessary.
329 void AdvancedThresholdPolicy::create_mdo(methodHandle mh, JavaThread* THREAD) {
330 if (mh->is_native() ||
331 mh->is_abstract() ||
332 mh->is_accessor() ||
333 mh->is_constant_getter()) {
334 return;
335 }
336 if (mh->method_data() == NULL) {
337 Method::build_interpreter_method_data(mh, CHECK_AND_CLEAR);
338 }
339 }
340
341
342 /*
343 * Method states:
344 * 0 - interpreter (CompLevel_none)
345 * 1 - pure C1 (CompLevel_simple)
346 * 2 - C1 with invocation and backedge counting (CompLevel_limited_profile)
347 * 3 - C1 with full profiling (CompLevel_full_profile)
348 * 4 - C2 (CompLevel_full_optimization)
349 *
350 * Common state transition patterns:
351 * a. 0 -> 3 -> 4.
352 * The most common path. But note that even in this straightforward case
353 * profiling can start at level 0 and finish at level 3.
354 *
355 * b. 0 -> 2 -> 3 -> 4.
356 * This case occurs when the load on C2 is deemed too high. So, instead of transitioning
357 * into state 3 directly and over-profiling while a method is in the C2 queue we transition to
358 * level 2 and wait until the load on C2 decreases. This path is disabled for OSRs.
359 *
360 * c. 0 -> (3->2) -> 4.
361 * In this case we enqueue a method for compilation at level 3, but the C1 queue is long enough
362 * to enable the profiling to fully occur at level 0. In this case we change the compilation level
363 * of the method to 2 while the request is still in-queue, because it'll allow it to run much faster
364 * without full profiling while c2 is compiling.
365 *
366 * d. 0 -> 3 -> 1 or 0 -> 2 -> 1.
367 * After a method was once compiled with C1 it can be identified as trivial and be compiled to
368 * level 1. These transition can also occur if a method can't be compiled with C2 but can with C1.
369 *
370 * e. 0 -> 4.
371 * This can happen if a method fails C1 compilation (it will still be profiled in the interpreter)
372 * or because of a deopt that didn't require reprofiling (compilation won't happen in this case because
373 * the compiled version already exists).
374 *
375 * Note that since state 0 can be reached from any other state via deoptimization different loops
376 * are possible.
377 *
378 */
379
380 // Common transition function. Given a predicate determines if a method should transition to another level.
381 CompLevel AdvancedThresholdPolicy::common(Predicate p, Method* method, CompLevel cur_level, bool disable_feedback) {
382 CompLevel next_level = cur_level;
383 int i = method->invocation_count();
384 int b = method->backedge_count();
385
386 if (is_trivial(method)) {
387 next_level = CompLevel_simple;
388 } else {
389 switch(cur_level) {
390 case CompLevel_none:
391 // If we were at full profile level, would we switch to full opt?
392 if (common(p, method, CompLevel_full_profile, disable_feedback) == CompLevel_full_optimization) {
393 next_level = CompLevel_full_optimization;
394 } else if ((this->*p)(i, b, cur_level, method)) {
395 #if INCLUDE_JVMCI
396 if (UseJVMCICompiler) {
397 // Since JVMCI takes a while to warm up, its queue inevitably backs up during
398 // early VM execution.
399 next_level = CompLevel_full_profile;
400 break;
401 }
402 #endif
403 // C1-generated fully profiled code is about 30% slower than the limited profile
404 // code that has only invocation and backedge counters. The observation is that
405 // if C2 queue is large enough we can spend too much time in the fully profiled code
406 // while waiting for C2 to pick the method from the queue. To alleviate this problem
407 // we introduce a feedback on the C2 queue size. If the C2 queue is sufficiently long
408 // we choose to compile a limited profiled version and then recompile with full profiling
409 // when the load on C2 goes down.
410 if (!disable_feedback && CompileBroker::queue_size(CompLevel_full_optimization) >
411 Tier3DelayOn * compiler_count(CompLevel_full_optimization)) {
412 next_level = CompLevel_limited_profile;
413 } else {
414 next_level = CompLevel_full_profile;
415 }
416 }
417 break;
418 case CompLevel_limited_profile:
419 if (is_method_profiled(method)) {
420 // Special case: we got here because this method was fully profiled in the interpreter.
421 next_level = CompLevel_full_optimization;
422 } else {
423 MethodData* mdo = method->method_data();
424 if (mdo != NULL) {
425 if (mdo->would_profile()) {
426 if (disable_feedback || (CompileBroker::queue_size(CompLevel_full_optimization) <=
427 Tier3DelayOff * compiler_count(CompLevel_full_optimization) &&
428 (this->*p)(i, b, cur_level, method))) {
429 next_level = CompLevel_full_profile;
430 }
431 } else {
432 next_level = CompLevel_full_optimization;
433 }
434 }
435 }
436 break;
437 case CompLevel_full_profile:
438 {
439 MethodData* mdo = method->method_data();
440 if (mdo != NULL) {
441 if (mdo->would_profile()) {
442 int mdo_i = mdo->invocation_count_delta();
443 int mdo_b = mdo->backedge_count_delta();
444 if ((this->*p)(mdo_i, mdo_b, cur_level, method)) {
445 next_level = CompLevel_full_optimization;
446 }
447 } else {
448 next_level = CompLevel_full_optimization;
449 }
450 }
451 }
452 break;
453 }
454 }
455 return MIN2(next_level, (CompLevel)TieredStopAtLevel);
456 }
457
458 // Determine if a method should be compiled with a normal entry point at a different level.
459 CompLevel AdvancedThresholdPolicy::call_event(Method* method, CompLevel cur_level, JavaThread * thread) {
460 CompLevel osr_level = MIN2((CompLevel) method->highest_osr_comp_level(),
461 common(&AdvancedThresholdPolicy::loop_predicate, method, cur_level, true));
462 CompLevel next_level = common(&AdvancedThresholdPolicy::call_predicate, method, cur_level);
463
464 // If OSR method level is greater than the regular method level, the levels should be
465 // equalized by raising the regular method level in order to avoid OSRs during each
466 // invocation of the method.
467 if (osr_level == CompLevel_full_optimization && cur_level == CompLevel_full_profile) {
468 MethodData* mdo = method->method_data();
469 guarantee(mdo != NULL, "MDO should not be NULL");
470 if (mdo->invocation_count() >= 1) {
471 next_level = CompLevel_full_optimization;
472 }
473 } else {
474 next_level = MAX2(osr_level, next_level);
475 }
476 #if INCLUDE_JVMCI
477 if (UseJVMCICompiler) {
478 next_level = JVMCIRuntime::adjust_comp_level(method, false, next_level, thread);
479 }
480 #endif
481 return next_level;
482 }
483
484 // Determine if we should do an OSR compilation of a given method.
485 CompLevel AdvancedThresholdPolicy::loop_event(Method* method, CompLevel cur_level, JavaThread * thread) {
486 CompLevel next_level = common(&AdvancedThresholdPolicy::loop_predicate, method, cur_level, true);
487 if (cur_level == CompLevel_none) {
488 // If there is a live OSR method that means that we deopted to the interpreter
489 // for the transition.
490 CompLevel osr_level = MIN2((CompLevel)method->highest_osr_comp_level(), next_level);
491 if (osr_level > CompLevel_none) {
492 return osr_level;
493 }
494 }
495 #if INCLUDE_JVMCI
496 if (UseJVMCICompiler) {
497 next_level = JVMCIRuntime::adjust_comp_level(method, true, next_level, thread);
498 }
499 #endif
500 return next_level;
501 }
502
503 // Update the rate and submit compile
504 void AdvancedThresholdPolicy::submit_compile(const methodHandle& mh, int bci, CompLevel level, JavaThread* thread) {
505 int hot_count = (bci == InvocationEntryBci) ? mh->invocation_count() : mh->backedge_count();
506 update_rate(os::javaTimeMillis(), mh());
507 CompileBroker::compile_method(mh, bci, level, mh, hot_count, CompileTask::Reason_Tiered, thread);
508 }
509
510 // Handle the invocation event.
511 void AdvancedThresholdPolicy::method_invocation_event(const methodHandle& mh, const methodHandle& imh,
512 CompLevel level, CompiledMethod* nm, JavaThread* thread) {
513 if (should_create_mdo(mh(), level)) {
514 create_mdo(mh, thread);
515 }
516 if (is_compilation_enabled() && !CompileBroker::compilation_is_in_queue(mh)) {
517 CompLevel next_level = call_event(mh(), level, thread);
518 if (next_level != level) {
519 compile(mh, InvocationEntryBci, next_level, thread);
520 }
521 }
522 }
523
524 // Handle the back branch event. Notice that we can compile the method
525 // with a regular entry from here.
526 void AdvancedThresholdPolicy::method_back_branch_event(const methodHandle& mh, const methodHandle& imh,
527 int bci, CompLevel level, CompiledMethod* nm, JavaThread* thread) {
528 if (should_create_mdo(mh(), level)) {
529 create_mdo(mh, thread);
530 }
531 // Check if MDO should be created for the inlined method
532 if (should_create_mdo(imh(), level)) {
533 create_mdo(imh, thread);
534 }
535
536 if (is_compilation_enabled()) {
537 CompLevel next_osr_level = loop_event(imh(), level, thread);
538 CompLevel max_osr_level = (CompLevel)imh->highest_osr_comp_level();
539 // At the very least compile the OSR version
540 if (!CompileBroker::compilation_is_in_queue(imh) && (next_osr_level != level)) {
541 compile(imh, bci, next_osr_level, thread);
542 }
543
544 // Use loop event as an opportunity to also check if there's been
545 // enough calls.
546 CompLevel cur_level, next_level;
547 if (mh() != imh()) { // If there is an enclosing method
548 guarantee(nm != NULL, "Should have nmethod here");
549 cur_level = comp_level(mh());
550 next_level = call_event(mh(), cur_level, thread);
551
552 if (max_osr_level == CompLevel_full_optimization) {
553 // The inlinee OSRed to full opt, we need to modify the enclosing method to avoid deopts
554 bool make_not_entrant = false;
555 if (nm->is_osr_method()) {
556 // This is an osr method, just make it not entrant and recompile later if needed
557 make_not_entrant = true;
558 } else {
559 if (next_level != CompLevel_full_optimization) {
560 // next_level is not full opt, so we need to recompile the
561 // enclosing method without the inlinee
562 cur_level = CompLevel_none;
563 make_not_entrant = true;
564 }
565 }
566 if (make_not_entrant) {
567 if (PrintTieredEvents) {
568 int osr_bci = nm->is_osr_method() ? nm->osr_entry_bci() : InvocationEntryBci;
569 print_event(MAKE_NOT_ENTRANT, mh(), mh(), osr_bci, level);
570 }
571 nm->make_not_entrant();
572 }
573 }
574 if (!CompileBroker::compilation_is_in_queue(mh)) {
575 // Fix up next_level if necessary to avoid deopts
576 if (next_level == CompLevel_limited_profile && max_osr_level == CompLevel_full_profile) {
577 next_level = CompLevel_full_profile;
578 }
579 if (cur_level != next_level) {
580 compile(mh, InvocationEntryBci, next_level, thread);
581 }
582 }
583 } else {
584 cur_level = comp_level(imh());
585 next_level = call_event(imh(), cur_level, thread);
586 if (!CompileBroker::compilation_is_in_queue(imh) && (next_level != cur_level)) {
587 compile(imh, InvocationEntryBci, next_level, thread);
588 }
589 }
590 }
591 }
592
593 #endif // TIERED