1 /*
2 * Copyright (c) 2000, 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/compiledIC.hpp"
27 #include "code/nmethod.hpp"
28 #include "code/scopeDesc.hpp"
29 #include "interpreter/interpreter.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "oops/methodData.hpp"
32 #include "oops/method.hpp"
33 #include "oops/oop.inline.hpp"
34 #include "prims/nativeLookup.hpp"
35 #include "runtime/advancedThresholdPolicy.hpp"
36 #include "runtime/compilationPolicy.hpp"
37 #include "runtime/frame.hpp"
38 #include "runtime/handles.inline.hpp"
39 #include "runtime/rframe.hpp"
40 #include "runtime/simpleThresholdPolicy.hpp"
41 #include "runtime/stubRoutines.hpp"
42 #include "runtime/thread.hpp"
43 #include "runtime/timer.hpp"
44 #include "runtime/vframe.hpp"
45 #include "runtime/vm_operations.hpp"
46 #include "utilities/events.hpp"
47 #include "utilities/globalDefinitions.hpp"
48
49 CompilationPolicy* CompilationPolicy::_policy;
50 elapsedTimer CompilationPolicy::_accumulated_time;
51 bool CompilationPolicy::_in_vm_startup;
52
53 // Determine compilation policy based on command line argument
54 void compilationPolicy_init() {
55 CompilationPolicy::set_in_vm_startup(DelayCompilationDuringStartup);
56
57 switch(CompilationPolicyChoice) {
58 case 0:
59 CompilationPolicy::set_policy(new SimpleCompPolicy());
60 break;
61
62 case 1:
63 #ifdef COMPILER2
64 CompilationPolicy::set_policy(new StackWalkCompPolicy());
65 #else
66 Unimplemented();
67 #endif
68 break;
69 case 2:
70 #ifdef TIERED
71 CompilationPolicy::set_policy(new SimpleThresholdPolicy());
72 #else
73 Unimplemented();
74 #endif
75 break;
76 case 3:
77 #ifdef TIERED
78 CompilationPolicy::set_policy(new AdvancedThresholdPolicy());
79 #else
80 Unimplemented();
81 #endif
82 break;
83 default:
84 fatal("CompilationPolicyChoice must be in the range: [0-3]");
85 }
86 CompilationPolicy::policy()->initialize();
87 }
88
89 void CompilationPolicy::completed_vm_startup() {
90 if (TraceCompilationPolicy) {
91 tty->print("CompilationPolicy: completed vm startup.\n");
92 }
93 _in_vm_startup = false;
94 }
95
96 // Returns true if m must be compiled before executing it
97 // This is intended to force compiles for methods (usually for
98 // debugging) that would otherwise be interpreted for some reason.
99 bool CompilationPolicy::must_be_compiled(methodHandle m, int comp_level) {
100 // Don't allow Xcomp to cause compiles in replay mode
101 if (ReplayCompiles) return false;
102
103 if (m->has_compiled_code()) return false; // already compiled
104 if (!can_be_compiled(m, comp_level)) return false;
105
106 return !UseInterpreter || // must compile all methods
107 (UseCompiler && AlwaysCompileLoopMethods && m->has_loops() && CompileBroker::should_compile_new_jobs()); // eagerly compile loop methods
108 }
109
110 // Returns true if m is allowed to be compiled
111 bool CompilationPolicy::can_be_compiled(methodHandle m, int comp_level) {
112 // allow any levels for WhiteBox
113 assert(WhiteBoxAPI || comp_level == CompLevel_all || is_compile(comp_level), "illegal compilation level");
114
115 if (m->is_abstract()) return false;
116 if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false;
117
118 // Math intrinsics should never be compiled as this can lead to
119 // monotonicity problems because the interpreter will prefer the
120 // compiled code to the intrinsic version. This can't happen in
121 // production because the invocation counter can't be incremented
122 // but we shouldn't expose the system to this problem in testing
123 // modes.
124 if (!AbstractInterpreter::can_be_compiled(m)) {
125 return false;
126 }
127 if (comp_level == CompLevel_all) {
128 if (TieredCompilation) {
129 // enough to be compilable at any level for tiered
130 return !m->is_not_compilable(CompLevel_simple) || !m->is_not_compilable(CompLevel_full_optimization);
131 } else {
132 // must be compilable at available level for non-tiered
133 return !m->is_not_compilable(CompLevel_highest_tier);
134 }
135 } else if (is_compile(comp_level)) {
136 return !m->is_not_compilable(comp_level);
137 }
138 return false;
139 }
140
141 // Returns true if m is allowed to be osr compiled
142 bool CompilationPolicy::can_be_osr_compiled(methodHandle m, int comp_level) {
143 bool result = false;
144 if (comp_level == CompLevel_all) {
145 if (TieredCompilation) {
146 // enough to be osr compilable at any level for tiered
147 result = !m->is_not_osr_compilable(CompLevel_simple) || !m->is_not_osr_compilable(CompLevel_full_optimization);
148 } else {
149 // must be osr compilable at available level for non-tiered
150 result = !m->is_not_osr_compilable(CompLevel_highest_tier);
151 }
152 } else if (is_compile(comp_level)) {
153 result = !m->is_not_osr_compilable(comp_level);
154 }
155 return (result && can_be_compiled(m, comp_level));
156 }
157
158 bool CompilationPolicy::is_compilation_enabled() {
159 // NOTE: CompileBroker::should_compile_new_jobs() checks for UseCompiler
160 return !delay_compilation_during_startup() && CompileBroker::should_compile_new_jobs();
161 }
162
163 CompileTask* CompilationPolicy::select_task_helper(CompileQueue* compile_queue) {
164 #if INCLUDE_JVMCI
165 if (UseJVMCICompiler && !BackgroundCompilation) {
166 /*
167 * In blocking compilation mode, the CompileBroker will make
168 * compilations submitted by a JVMCI compiler thread non-blocking. These
169 * compilations should be scheduled after all blocking compilations
170 * to service non-compiler related compilations sooner and reduce the
171 * chance of such compilations timing out.
172 */
173 for (CompileTask* task = compile_queue->first(); task != NULL; task = task->next()) {
174 if (task->is_blocking()) {
175 return task;
176 }
177 }
178 }
179 #endif
180 return compile_queue->first();
181 }
182
183 #ifndef PRODUCT
184 void CompilationPolicy::print_time() {
185 tty->print_cr ("Accumulated compilationPolicy times:");
186 tty->print_cr ("---------------------------");
187 tty->print_cr (" Total: %3.3f sec.", _accumulated_time.seconds());
188 }
189
190 void NonTieredCompPolicy::trace_osr_completion(nmethod* osr_nm) {
191 if (TraceOnStackReplacement) {
192 if (osr_nm == NULL) tty->print_cr("compilation failed");
193 else tty->print_cr("nmethod " INTPTR_FORMAT, p2i(osr_nm));
194 }
195 }
196 #endif // !PRODUCT
197
198 void NonTieredCompPolicy::initialize() {
199 // Setup the compiler thread numbers
200 if (CICompilerCountPerCPU) {
201 // Example: if CICompilerCountPerCPU is true, then we get
202 // max(log2(8)-1,1) = 2 compiler threads on an 8-way machine.
203 // May help big-app startup time.
204 _compiler_count = MAX2(log2_intptr(os::active_processor_count())-1,1);
205 FLAG_SET_ERGO(intx, CICompilerCount, _compiler_count);
206 } else {
207 _compiler_count = CICompilerCount;
208 }
209 }
210
211 // Note: this policy is used ONLY if TieredCompilation is off.
212 // compiler_count() behaves the following way:
213 // - with TIERED build (with both COMPILER1 and COMPILER2 defined) it should return
214 // zero for the c1 compilation levels, hence the particular ordering of the
215 // statements.
216 // - the same should happen when COMPILER2 is defined and COMPILER1 is not
217 // (server build without TIERED defined).
218 // - if only COMPILER1 is defined (client build), zero should be returned for
219 // the c2 level.
220 // - if neither is defined - always return zero.
221 int NonTieredCompPolicy::compiler_count(CompLevel comp_level) {
222 assert(!TieredCompilation, "This policy should not be used with TieredCompilation");
223 #ifdef COMPILER2
224 if (is_c2_compile(comp_level)) {
225 return _compiler_count;
226 } else {
227 return 0;
228 }
229 #endif
230
231 #ifdef COMPILER1
232 if (is_c1_compile(comp_level)) {
233 return _compiler_count;
234 } else {
235 return 0;
236 }
237 #endif
238
239 return 0;
240 }
241
242 void NonTieredCompPolicy::reset_counter_for_invocation_event(const methodHandle& m) {
243 // Make sure invocation and backedge counter doesn't overflow again right away
244 // as would be the case for native methods.
245
246 // BUT also make sure the method doesn't look like it was never executed.
247 // Set carry bit and reduce counter's value to min(count, CompileThreshold/2).
248 MethodCounters* mcs = m->method_counters();
249 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
250 mcs->invocation_counter()->set_carry();
251 mcs->backedge_counter()->set_carry();
252
253 assert(!m->was_never_executed(), "don't reset to 0 -- could be mistaken for never-executed");
254 }
255
256 void NonTieredCompPolicy::reset_counter_for_back_branch_event(const methodHandle& m) {
257 // Delay next back-branch event but pump up invocation counter to trigger
258 // whole method compilation.
259 MethodCounters* mcs = m->method_counters();
260 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
261 InvocationCounter* i = mcs->invocation_counter();
262 InvocationCounter* b = mcs->backedge_counter();
263
264 // Don't set invocation_counter's value too low otherwise the method will
265 // look like immature (ic < ~5300) which prevents the inlining based on
266 // the type profiling.
267 i->set(i->state(), CompileThreshold);
268 // Don't reset counter too low - it is used to check if OSR method is ready.
269 b->set(b->state(), CompileThreshold / 2);
270 }
271
272 //
273 // CounterDecay
274 //
275 // Iterates through invocation counters and decrements them. This
276 // is done at each safepoint.
277 //
278 class CounterDecay : public AllStatic {
279 static jlong _last_timestamp;
280 static void do_method(Method* m) {
281 MethodCounters* mcs = m->method_counters();
282 if (mcs != NULL) {
283 mcs->invocation_counter()->decay();
284 }
285 }
286 public:
287 static void decay();
288 static bool is_decay_needed() {
289 return (os::javaTimeMillis() - _last_timestamp) > CounterDecayMinIntervalLength;
290 }
291 };
292
293 jlong CounterDecay::_last_timestamp = 0;
294
295 void CounterDecay::decay() {
296 _last_timestamp = os::javaTimeMillis();
297
298 // This operation is going to be performed only at the end of a safepoint
299 // and hence GC's will not be going on, all Java mutators are suspended
300 // at this point and hence SystemDictionary_lock is also not needed.
301 assert(SafepointSynchronize::is_at_safepoint(), "can only be executed at a safepoint");
302 int nclasses = SystemDictionary::number_of_classes();
303 double classes_per_tick = nclasses * (CounterDecayMinIntervalLength * 1e-3 /
304 CounterHalfLifeTime);
305 for (int i = 0; i < classes_per_tick; i++) {
306 Klass* k = SystemDictionary::try_get_next_class();
307 if (k != NULL && k->is_instance_klass()) {
308 InstanceKlass::cast(k)->methods_do(do_method);
309 }
310 }
311 }
312
313 // Called at the end of the safepoint
314 void NonTieredCompPolicy::do_safepoint_work() {
315 if(UseCounterDecay && CounterDecay::is_decay_needed()) {
316 CounterDecay::decay();
317 }
318 }
319
320 void NonTieredCompPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) {
321 ScopeDesc* sd = trap_scope;
322 MethodCounters* mcs;
323 InvocationCounter* c;
324 for (; !sd->is_top(); sd = sd->sender()) {
325 mcs = sd->method()->method_counters();
326 if (mcs != NULL) {
327 // Reset ICs of inlined methods, since they can trigger compilations also.
328 mcs->invocation_counter()->reset();
329 }
330 }
331 mcs = sd->method()->method_counters();
332 if (mcs != NULL) {
333 c = mcs->invocation_counter();
334 if (is_osr) {
335 // It was an OSR method, so bump the count higher.
336 c->set(c->state(), CompileThreshold);
337 } else {
338 c->reset();
339 }
340 mcs->backedge_counter()->reset();
341 }
342 }
343
344 // This method can be called by any component of the runtime to notify the policy
345 // that it's recommended to delay the compilation of this method.
346 void NonTieredCompPolicy::delay_compilation(Method* method) {
347 MethodCounters* mcs = method->method_counters();
348 if (mcs != NULL) {
349 mcs->invocation_counter()->decay();
350 mcs->backedge_counter()->decay();
351 }
352 }
353
354 void NonTieredCompPolicy::disable_compilation(Method* method) {
355 MethodCounters* mcs = method->method_counters();
356 if (mcs != NULL) {
357 mcs->invocation_counter()->set_state(InvocationCounter::wait_for_nothing);
358 mcs->backedge_counter()->set_state(InvocationCounter::wait_for_nothing);
359 }
360 }
361
362 CompileTask* NonTieredCompPolicy::select_task(CompileQueue* compile_queue) {
363 return select_task_helper(compile_queue);
364 }
365
366 bool NonTieredCompPolicy::is_mature(Method* method) {
367 MethodData* mdo = method->method_data();
368 assert(mdo != NULL, "Should be");
369 uint current = mdo->mileage_of(method);
370 uint initial = mdo->creation_mileage();
371 if (current < initial)
372 return true; // some sort of overflow
373 uint target;
374 if (ProfileMaturityPercentage <= 0)
375 target = (uint) -ProfileMaturityPercentage; // absolute value
376 else
377 target = (uint)( (ProfileMaturityPercentage * CompileThreshold) / 100 );
378 return (current >= initial + target);
379 }
380
381 nmethod* NonTieredCompPolicy::event(const methodHandle& method, const methodHandle& inlinee, int branch_bci,
382 int bci, CompLevel comp_level, nmethod* nm, JavaThread* thread) {
383 assert(comp_level == CompLevel_none, "This should be only called from the interpreter");
384 NOT_PRODUCT(trace_frequency_counter_overflow(method, branch_bci, bci));
385 if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
386 // If certain JVMTI events (e.g. frame pop event) are requested then the
387 // thread is forced to remain in interpreted code. This is
388 // implemented partly by a check in the run_compiled_code
389 // section of the interpreter whether we should skip running
390 // compiled code, and partly by skipping OSR compiles for
391 // interpreted-only threads.
392 if (bci != InvocationEntryBci) {
393 reset_counter_for_back_branch_event(method);
394 return NULL;
395 }
396 }
397 if (CompileTheWorld || ReplayCompiles) {
398 // Don't trigger other compiles in testing mode
399 if (bci == InvocationEntryBci) {
400 reset_counter_for_invocation_event(method);
401 } else {
402 reset_counter_for_back_branch_event(method);
403 }
404 return NULL;
405 }
406
407 if (bci == InvocationEntryBci) {
408 // when code cache is full, compilation gets switched off, UseCompiler
409 // is set to false
410 if (!method->has_compiled_code() && UseCompiler) {
411 method_invocation_event(method, thread);
412 } else {
413 // Force counter overflow on method entry, even if no compilation
414 // happened. (The method_invocation_event call does this also.)
415 reset_counter_for_invocation_event(method);
416 }
417 // compilation at an invocation overflow no longer goes and retries test for
418 // compiled method. We always run the loser of the race as interpreted.
419 // so return NULL
420 return NULL;
421 } else {
422 // counter overflow in a loop => try to do on-stack-replacement
423 nmethod* osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
424 NOT_PRODUCT(trace_osr_request(method, osr_nm, bci));
425 // when code cache is full, we should not compile any more...
426 if (osr_nm == NULL && UseCompiler) {
427 method_back_branch_event(method, bci, thread);
428 osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
429 }
430 if (osr_nm == NULL) {
431 reset_counter_for_back_branch_event(method);
432 return NULL;
433 }
434 return osr_nm;
435 }
436 return NULL;
437 }
438
439 #ifndef PRODUCT
440 void NonTieredCompPolicy::trace_frequency_counter_overflow(const methodHandle& m, int branch_bci, int bci) {
441 if (TraceInvocationCounterOverflow) {
442 MethodCounters* mcs = m->method_counters();
443 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
444 InvocationCounter* ic = mcs->invocation_counter();
445 InvocationCounter* bc = mcs->backedge_counter();
446 ResourceMark rm;
447 if (bci == InvocationEntryBci) {
448 tty->print("comp-policy cntr ovfl @ %d in entry of ", bci);
449 } else {
450 tty->print("comp-policy cntr ovfl @ %d in loop of ", bci);
451 }
452 m->print_value();
453 tty->cr();
454 ic->print();
455 bc->print();
456 if (ProfileInterpreter) {
457 if (bci != InvocationEntryBci) {
458 MethodData* mdo = m->method_data();
459 if (mdo != NULL) {
460 int count = mdo->bci_to_data(branch_bci)->as_JumpData()->taken();
461 tty->print_cr("back branch count = %d", count);
462 }
463 }
464 }
465 }
466 }
467
468 void NonTieredCompPolicy::trace_osr_request(const methodHandle& method, nmethod* osr, int bci) {
469 if (TraceOnStackReplacement) {
470 ResourceMark rm;
471 tty->print(osr != NULL ? "Reused OSR entry for " : "Requesting OSR entry for ");
472 method->print_short_name(tty);
473 tty->print_cr(" at bci %d", bci);
474 }
475 }
476 #endif // !PRODUCT
477
478 // SimpleCompPolicy - compile current method
479
480 void SimpleCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) {
481 const int comp_level = CompLevel_highest_tier;
482 const int hot_count = m->invocation_count();
483 reset_counter_for_invocation_event(m);
484 const char* comment = "count";
485
486 if (is_compilation_enabled() && can_be_compiled(m, comp_level)) {
487 nmethod* nm = m->code();
488 if (nm == NULL ) {
489 CompileBroker::compile_method(m, InvocationEntryBci, comp_level, m, hot_count, comment, thread);
490 }
491 }
492 }
493
494 void SimpleCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) {
495 const int comp_level = CompLevel_highest_tier;
496 const int hot_count = m->backedge_count();
497 const char* comment = "backedge_count";
498
499 if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) {
500 CompileBroker::compile_method(m, bci, comp_level, m, hot_count, comment, thread);
501 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));)
502 }
503 }
504 // StackWalkCompPolicy - walk up stack to find a suitable method to compile
505
506 #ifdef COMPILER2
507 const char* StackWalkCompPolicy::_msg = NULL;
508
509
510 // Consider m for compilation
511 void StackWalkCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) {
512 const int comp_level = CompLevel_highest_tier;
513 const int hot_count = m->invocation_count();
514 reset_counter_for_invocation_event(m);
515 const char* comment = "count";
516
517 if (is_compilation_enabled() && m->code() == NULL && can_be_compiled(m, comp_level)) {
518 ResourceMark rm(thread);
519 frame fr = thread->last_frame();
520 assert(fr.is_interpreted_frame(), "must be interpreted");
521 assert(fr.interpreter_frame_method() == m(), "bad method");
522
523 if (TraceCompilationPolicy) {
524 tty->print("method invocation trigger: ");
525 m->print_short_name(tty);
526 tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", p2i((address)m()), m->code_size());
527 }
528 RegisterMap reg_map(thread, false);
529 javaVFrame* triggerVF = thread->last_java_vframe(®_map);
530 // triggerVF is the frame that triggered its counter
531 RFrame* first = new InterpretedRFrame(triggerVF->fr(), thread, m());
532
533 if (first->top_method()->code() != NULL) {
534 // called obsolete method/nmethod -- no need to recompile
535 if (TraceCompilationPolicy) tty->print_cr(" --> " INTPTR_FORMAT, p2i(first->top_method()->code()));
536 } else {
537 if (TimeCompilationPolicy) accumulated_time()->start();
538 GrowableArray<RFrame*>* stack = new GrowableArray<RFrame*>(50);
539 stack->push(first);
540 RFrame* top = findTopInlinableFrame(stack);
541 if (TimeCompilationPolicy) accumulated_time()->stop();
542 assert(top != NULL, "findTopInlinableFrame returned null");
543 if (TraceCompilationPolicy) top->print();
544 CompileBroker::compile_method(top->top_method(), InvocationEntryBci, comp_level,
545 m, hot_count, comment, thread);
546 }
547 }
548 }
549
550 void StackWalkCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) {
551 const int comp_level = CompLevel_highest_tier;
552 const int hot_count = m->backedge_count();
553 const char* comment = "backedge_count";
554
555 if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) {
556 CompileBroker::compile_method(m, bci, comp_level, m, hot_count, comment, thread);
557 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));)
558 }
559 }
560
561 RFrame* StackWalkCompPolicy::findTopInlinableFrame(GrowableArray<RFrame*>* stack) {
562 // go up the stack until finding a frame that (probably) won't be inlined
563 // into its caller
564 RFrame* current = stack->at(0); // current choice for stopping
565 assert( current && !current->is_compiled(), "" );
566 const char* msg = NULL;
567
568 while (1) {
569
570 // before going up the stack further, check if doing so would get us into
571 // compiled code
572 RFrame* next = senderOf(current, stack);
573 if( !next ) // No next frame up the stack?
574 break; // Then compile with current frame
575
576 Method* m = current->top_method();
577 Method* next_m = next->top_method();
578
579 if (TraceCompilationPolicy && Verbose) {
580 tty->print("[caller: ");
581 next_m->print_short_name(tty);
582 tty->print("] ");
583 }
584
585 if( !Inline ) { // Inlining turned off
586 msg = "Inlining turned off";
587 break;
588 }
589 if (next_m->is_not_compilable()) { // Did fail to compile this before/
590 msg = "caller not compilable";
591 break;
592 }
593 if (next->num() > MaxRecompilationSearchLength) {
594 // don't go up too high when searching for recompilees
595 msg = "don't go up any further: > MaxRecompilationSearchLength";
596 break;
597 }
598 if (next->distance() > MaxInterpretedSearchLength) {
599 // don't go up too high when searching for recompilees
600 msg = "don't go up any further: next > MaxInterpretedSearchLength";
601 break;
602 }
603 // Compiled frame above already decided not to inline;
604 // do not recompile him.
605 if (next->is_compiled()) {
606 msg = "not going up into optimized code";
607 break;
608 }
609
610 // Interpreted frame above us was already compiled. Do not force
611 // a recompile, although if the frame above us runs long enough an
612 // OSR might still happen.
613 if( current->is_interpreted() && next_m->has_compiled_code() ) {
614 msg = "not going up -- already compiled caller";
615 break;
616 }
617
618 // Compute how frequent this call site is. We have current method 'm'.
619 // We know next method 'next_m' is interpreted. Find the call site and
620 // check the various invocation counts.
621 int invcnt = 0; // Caller counts
622 if (ProfileInterpreter) {
623 invcnt = next_m->interpreter_invocation_count();
624 }
625 int cnt = 0; // Call site counts
626 if (ProfileInterpreter && next_m->method_data() != NULL) {
627 ResourceMark rm;
628 int bci = next->top_vframe()->bci();
629 ProfileData* data = next_m->method_data()->bci_to_data(bci);
630 if (data != NULL && data->is_CounterData())
631 cnt = data->as_CounterData()->count();
632 }
633
634 // Caller counts / call-site counts; i.e. is this call site
635 // a hot call site for method next_m?
636 int freq = (invcnt) ? cnt/invcnt : cnt;
637
638 // Check size and frequency limits
639 if ((msg = shouldInline(m, freq, cnt)) != NULL) {
640 break;
641 }
642 // Check inlining negative tests
643 if ((msg = shouldNotInline(m)) != NULL) {
644 break;
645 }
646
647
648 // If the caller method is too big or something then we do not want to
649 // compile it just to inline a method
650 if (!can_be_compiled(next_m, CompLevel_any)) {
651 msg = "caller cannot be compiled";
652 break;
653 }
654
655 if( next_m->name() == vmSymbols::class_initializer_name() ) {
656 msg = "do not compile class initializer (OSR ok)";
657 break;
658 }
659
660 if (TraceCompilationPolicy && Verbose) {
661 tty->print("\n\t check caller: ");
662 next_m->print_short_name(tty);
663 tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", p2i((address)next_m), next_m->code_size());
664 }
665
666 current = next;
667 }
668
669 assert( !current || !current->is_compiled(), "" );
670
671 if (TraceCompilationPolicy && msg) tty->print("(%s)\n", msg);
672
673 return current;
674 }
675
676 RFrame* StackWalkCompPolicy::senderOf(RFrame* rf, GrowableArray<RFrame*>* stack) {
677 RFrame* sender = rf->caller();
678 if (sender && sender->num() == stack->length()) stack->push(sender);
679 return sender;
680 }
681
682
683 const char* StackWalkCompPolicy::shouldInline(const methodHandle& m, float freq, int cnt) {
684 // Allows targeted inlining
685 // positive filter: should send be inlined? returns NULL (--> yes)
686 // or rejection msg
687 int max_size = MaxInlineSize;
688 int cost = m->code_size();
689
690 // Check for too many throws (and not too huge)
691 if (m->interpreter_throwout_count() > InlineThrowCount && cost < InlineThrowMaxSize ) {
692 return NULL;
693 }
694
695 // bump the max size if the call is frequent
696 if ((freq >= InlineFrequencyRatio) || (cnt >= InlineFrequencyCount)) {
697 if (TraceFrequencyInlining) {
698 tty->print("(Inlined frequent method)\n");
699 m->print();
700 }
701 max_size = FreqInlineSize;
702 }
703 if (cost > max_size) {
704 return (_msg = "too big");
705 }
706 return NULL;
707 }
708
709
710 const char* StackWalkCompPolicy::shouldNotInline(const methodHandle& m) {
711 // negative filter: should send NOT be inlined? returns NULL (--> inline) or rejection msg
712 if (m->is_abstract()) return (_msg = "abstract method");
713 // note: we allow ik->is_abstract()
714 if (!m->method_holder()->is_initialized()) return (_msg = "method holder not initialized");
715 if (m->is_native()) return (_msg = "native method");
716 nmethod* m_code = m->code();
717 if (m_code != NULL && m_code->code_size() > InlineSmallCode)
718 return (_msg = "already compiled into a big method");
719
720 // use frequency-based objections only for non-trivial methods
721 if (m->code_size() <= MaxTrivialSize) return NULL;
722 if (UseInterpreter) { // don't use counts with -Xcomp
723 if ((m->code() == NULL) && m->was_never_executed()) return (_msg = "never executed");
724 if (!m->was_executed_more_than(MIN2(MinInliningThreshold, CompileThreshold >> 1))) return (_msg = "executed < MinInliningThreshold times");
725 }
726 if (Method::has_unloaded_classes_in_signature(m, JavaThread::current())) return (_msg = "unloaded signature classes");
727
728 return NULL;
729 }
730
731
732
733 #endif // COMPILER2